SUBSTANCE: invention relates to a refrigeration circuit. The essence of the invention is the refrigeration circuit (3) for household appliances, in particular household appliances for cooling, such as refrigerators and freezers, comprises a first heat exchanger (5) made with the ability of fluid communication with the compressor (4), which provides cooling of cooling fluid medium which flows through it, and its transition to substantially liquid phase. It also comprises a second heat exchanger (7) fluidly communicating with the said first heat exchanger (5) and acting in the space (2) to be cooled. The second heat exchanger (7) provides a partial transition of the cooling fluid medium in gaseous phase with heat absorption thereby the said space (2) is cooled. The cooling fluid medium is circulated from the first heat exchanger (5) to the second heat exchanger (7) and, thus, enters into the compressor (4) for the next cycle. The capillary device (6) is located between the first heat exchanger (5) and the second (7) heat exchanger for expanding the said cooling fluid medium. One of the said first heat exchanger (5) and the second heat exchanger (7) comprises a flexible tube (9), and the part of the said tube (9) has such a corrugated profile, which gives it flexibility, and the said tube (9) in section comprises a layer (100) of plastic and a layer (101) comprising the metallic material. The metal layer (101) is connected to the plastic layer, and the said metallic material is configured with the ability to form a barrier against moisture. The said layer (100) of plastic is a layer the structural purpose of which is maintaining the shape of the tube (9), and is preferably made of a thermoplastic material. The metal layer (101) is flexible, it does not have a function of a supporting structure and comprises a single-layered metal film or a multilayer film comprising one or more metal films connected or not connected to the layer of material made with the ability to maintaining the shape.
EFFECT: improving the efficiency of heat exchanging and providing waterproofing.
16 cl, 27 dwg, 1 tbl
The present invention relates to a refrigerating circuit.
More specifically, the present invention relates to cooling apparatus is preferably of a type which is used in household appliances, such as refrigerators, freezers, freezer and deep freeze, refrigerators, etc. in Addition, this invention is similarly applicable to household appliances for air-conditioning.
It is known that the refrigerators of the traditional type and similar refrigerating apparatus includes a refrigeration circuit, where the used coolant, which is suitable for removal of heat from an enclosed space to be cooled to a predetermined temperature, such as the inner space of the refrigerator or freezer, and to transfer heat to a warmer outer space. The above-mentioned cooling circuit is a closed path, where the compressor, condenser, luminosidade or capillary device and the evaporator are sequentially according to known operating modes. In particular, the cooling means is a substance with a low boiling point, are able to experience a phase transition from liquid to vapor in the expansion with the effect of taking heat from the environment with which it is in contact, and then reverse transition from p is RA in the liquid during its circulation within the cooling loop. As for the heat exchange between the cooling means and air from an enclosed space to be cooled, and the external environment, such heat transfer occurs through metal coils which pass coolant to increase the surface of heat exchange between the coolant and the air.
Metal coils, which are used to implement such functions are usually obtained from a continuous metal pipe (steel, aluminum or copper), which is repeatedly bent in a suitable manner, to match the profile of useful surface, designed for heat transfer. This is useful surface is located on the back side of the fridge in the case of the capacitor, whereas in the case of the evaporator coils are located on one or more inside walls of the refrigerator, depending on the model of the cooling apparatus or the refrigerator, freezer or combined apparatus. In particular, know the location of the evaporator coil at the inner bottom wall and/or on the inner side walls of the refrigerator or even on one or more shelves provided inside the fridge. Depending on the location inside of the refrigerator and from the results you want to achieve, the evaporators can be static (promolocker the aqueous type (Wire On Tubes) or repicturing type (Tubes On Plates)or a dynamic system with automatic defrosting (No Frost)). In any case, provided the unit consisting of steel, or aluminum, or copper pipe, bent in a suitable manner and is welded or otherwise attached to other metal objects, which increase the heat exchange surface (metal wire in the case of the evaporator provocateuring type (WOT), the metal sheets in the case of the evaporator repicturing type (TOR) and aluminum sheets in the case of a system with automatic defrosting (NF)).
Bending metal pipes for the manufacture of evaporator coil is carried out according to various methods, depending on the geometric shape of the surface on which the coil must operate. In fact, bending metal pipes are usually carried out using a special tube bending machines before the final installation of the coil, and therefore it should be placed differently depending on the geometrical shape of the coil. Bending must be carried out in such a way as to avoid clogging or change sections in such zones.
This leads to reduced operational flexibility, due to the inability to provide a standard way of receiving coil, which remains constant only for refrigerators of the same model or the same series. This lack entails the application of various manufacturers is a significant processes, which greatly affects the production time and, as a direct consequence, leads to high production costs.
In addition, there are difficulties with storage, since it is necessary to provide storage of coils of different types, each of which is intended for installation only on a set of heat transfer surface having the desired geometrical form.
In addition, the production of the above-mentioned coils of metal tubing leads to additional production costs associated with the acquisition of raw materials (metal), handling of original materials, as well as with complex operations manufacturing metal pipes and flexible to obtain the final profile of the coil. In fact, the metal pipe is produced by welding a flat sheet, molded accordingly, such a process is very expensive and complex, because it must be implemented very carefully to avoid leakage of the cooling fluid, which can cause irreparable damage to the refrigerator for a very short time with serious economic consequences for the manufacturer and for the environment (such fluids often pollute the environment).
In addition, a metal pipe supply manufacturers evaporators in the form of rolls, and so the m way her unwind, straighten, check its diameter, and then repeatedly bend properly at an angle of 180° in alternating direction, to obtain the required heat transfer surface, and finally, attach to metal objects, having the form of plates or straight metal wire, suitable for facilitating heat exchange with the medium to be cooled. Connection with such metal wire is usually performed by means of spot welding (evaporator provocateuring type (WOT), or by the introduction of a tube bundle in a special slot made in aluminum plates (system with automatic defrosting (NF)). This is usually performed by means of manual operations that can be automated only to a certain extent due to the lack of flexibility of the production line, and also the need to create spot welds in WOT and points of welding the inlet and outlet pipes of the evaporator to other parts of the circuit is forced to chemical treatment, and then coating or plating processing of the entire surface of this part, to make it corrosion resistant. The obvious complexity of the above process of manufacturing the metal coils of the known type. Furthermore, the presence of a metal coil and metal objects significantly increases ABSU the mass and, therefore, the weight of the household appliance.
In addition, the above-mentioned additional chemical treatment is expensive and heavily pollute the environment (e.g., Nickel), because after this treatment produces a sludge containing heavy metals, which should be sent to special centers for the collection of toxic waste.
From the patent EP 1479987 known refrigerator comprising an evaporator, equipped with a flexible tube. Flexible tube made of plastic, has a cylindrical shape and is wound in a spiral around the respective supports; this spiral can be stretched or compressed to change its form depending on the part of the refrigerator, where required cooling effect.
However, the flexibility of the pipe is limited and it is possible to deform essentially along one direction, around which are wound coils.
In addition, the patent KR 20010094016 known refrigerator, equipped with evaporator made of plastic. To prevent known problems of frost formation, the evaporator having a rigid structure and molded in the form of a flat surface, limiting the cooling pipe and plate) includes a coating of a conductive paste, United with the outer metal conductor, and an additional outer insulating layer of plastic.
In the above-mentioned European patent software similar plastic pipe having a perfectly cylindrical shape, does not provide optimal heat exchange with a cooling fluid circulating in it. In addition, the above-mentioned cylindrical pipe, spiral wound, suitable for stretching or compression along a predetermined direction, however, does not show the properties of good flexibility in any direction, and, in particular, in the case of significant bending, such as a bend with a small radius, which is usually required in the manufacture of flat coils for refrigerators.
More specifically, this patent does not provide high performance in relation to operational flexibility and ability to adapt the geometrical shape of the heat exchanger, which currently are required on the market.
Moreover, in Korean patent does not mention the problems of adaptability and modular design of the heat exchanger.
The aforementioned patent also relates to the manufacture of the layer of conductive material enclosed between the inner plastic in contact with the cooling fluid medium, and the material of the outer coating, properties, and technology of application of which is not completely described.
In any case, in the above-mentioned patents are not solved one of the most the more important problems: how to prevent gas leakage through the surface of the evaporator or condenser or through devices to connect this device with other components of the cooling circuit. Perfect seal against any leakage of gas from the refrigerant circuit is a necessary condition for the correct operation of the refrigerator for several years.
In addition, the patent EP 918182 known manufacturer of flexible pipes for transfer of refrigerant in the air conditioning system. The design described in this patent, in any case, it seems very difficult, because it provides the first inner layer and an outer layer of plastic, which are connected by providing the intermediate layer. Provided by the external coating for pipes made of plastic, consisting of synthetic fibers, which, in turn, secured additional external shell. This complex structure makes the pipe described in this European patent, essentially is unsuitable for use in heat exchangers, which should provide heat transfer as such between the cooling fluid medium and the external environment. On the other hand, the pipe described in the aforementioned European patent, exclusively suitable for such transfer fluid, and not for heat exchange with the external environment, what happens in other, undescribed structures.
It should also be noted that it is known the use of plastic pipes for heat exchangers in devices that are completely different from cooling the circuits for household appliances.
In particular, such heat exchangers are designed for a wide variety of applications in the automotive industry.
For example, the known heat exchangers according to the US patents 2007/0289725 and US 5706864.
However, it should be noted that the device according to one or another of these patents cannot be used in refrigeration circuits according to the present invention, because of their scope makes them totally unsuitable for transfer of the cooling gas, which is usually used in household appliances, and they are unsuitable for performing heat exchange in the conditions, when circulating in them fluid is in the liquid phase and gaseous phase. These devices typically use only the fluid, which must operate at temperatures and pressures that are completely different from working temperatures and pressures that are typically used in a refrigerating circuit for household appliances.
In this regard, the use of a device described in the two above-mentioned patents, it is impossible, because the person skilled in the art will immediately detect many challenges for adaptation related to refrigerant leakage, insufficient heat, impossible to accurately maintain the speed of the fluid inside the pipe etc.
The technical problem of the present image is etenia is to provide a refrigeration circuit for household appliance, which lacks the above-mentioned disadvantages.
Within this technical problem, the purpose of this invention is to provide a household appliance for cooling, which should lead to high operational flexibility.
Another purpose of this invention is the provision of household appliance for cooling, which is made of simple, inexpensive and more environmentally friendly way.
Another purpose of this invention is the provision of household appliance for cooling, which is made with a greater degree of automation, thus, more reliable way, especially as regards the above-mentioned operations of welding, with the elimination of manual welding, which currently provide for the connection of various devices in the circuit with each other.
Another purpose of this invention is the combining, where possible, materials used for the manufacture of the various parts of the cooling system (currently, copper, aluminum and steel), and their replacement by plastic, compatible and recyclable without separation, to simplify the processes of storage of the same parts.
Also the purpose of this invention is the provision of household appliance for cooling, which has a smaller mass.
Another goal of this izobreteny who is providing household appliance for cooling, which has a high flexibility in many areas and, in particular, at small bending radii.
These and other purposes, as will be shown later in the present description of the invention, is essentially achieved through household appliance for cooling, with properties that are respectively expressed in claim 1 of the claims and/or one or more dependent claims.
This invention is based on the observation according to which the slow step of the process of heat transfer in modern refrigeration circuits is no heat transfer through the thickness of the pipe wall of the heat exchanger, and heat transfer by natural or forced convection system with automatic defrosting) between the air and the surface of the pipe.
To date, the heat exchangers for domestic appliances always made of metal material (even from very expensive, such as copper)in order to improve the conductivity of the tube. On the contrary, the present invention is applied plastic, less expensive, better workable, but with lower thermal conductivity, so that heat exchange process is not determined by the conductivity of the tube.
This refers to the thickness of the plastic pipe, not exceeding 1.5 mm; in order to increase the heat transfer Comte is a, it was suggested to influence the slow stage of the process (heat transfer between pipe and air), increasing the heat exchange surface by applying a pipe with corrugated surfaces, which is of the same diameter provides the opportunity of increasing the heat exchange surface by 30-50% per unit length of the pipe.
Below is preferred but not exclusive embodiment of a household appliance for cooling with a non-limiting example according to the present invention and the accompanying drawings, where:
- figure 1 shows a schematic representation of the refrigeration circuit according to the present invention, in particular, with evaporating tubes;
- figure 2 shows a perspective view of part of the refrigerant circuit household appliance according to the present invention;
- figure 3 shows the image, partially side view, partially in section, of the pipe, suitable for use in a refrigerating circuit according to the present invention and according to the first embodiment of the present invention;
on Figa shows a possible variant of the cross section of the pipe, is shown in figure 3;
- figure 4 shows the image, partially side view, partially in section, of parts shown in figure 3, consisting of a double layer of plastic suitable for making completely gas-tight tube wall according to another in which plamenu of the present invention;
- figure 5 and 6 shows two possible cross-section of the capillary tube, which is used in the circuit according to this invention;
- 7-10A shows the cross-section of possible embodiments of the heating means, which are used in the pipe according to this invention;
- on 11-13 shows various embodiments of connecting elements for connecting sections of pipe that are used in the circuit according to this invention;
on Fig and 15 shows the connection between the capillary tube and pipe according to the present invention;
on Figa, 14b and 14 C shows three possible connection between the capillary tube and corrugated pipe, obtained by co-extrusion or, at least, connected by a continuous way, in order to optimize heat transfer and energy recovery;
on Fig shows the connection between the metal pipe and plastic pipe according to the present invention;
on Fig-19 shows the connection between the two end sections of plastic pipes, which are used in the circuit according to the present invention;
on Fig illustrates a possible configuration of the connection between the corrugated pipe and the compressor or other smooth or corrugated pipe, and
on Figa and 21b show two possible configurations of the connection between the pipe and Capilla the Noah tube;
on Fig the picture shown, partially side view, partially in section, of the pipe, suitable for use in a refrigerating circuit according to the present invention, in another embodiment, which provides an easy connection between corrugated plastic pipe and attached to it a metal layer;
on Fig on an enlarged scale showing part of the cross-section of the pipe wall, depicted on Fig, and
on Fig shows a perspective view of the pipe shown on Fig and 23;
on Fig shows an alternative embodiment of the tube shown in Fig, in the context;
on Fig shows the shape of the corrugation of the pipe, an alternative to the previous drawings, the flat inner surfaces of the recesses, in order to minimize noise, which produces a gas flow inside the pipe, and
on Fig shows a cross-section of another alternative embodiment of the tube shown in Fig.
In the schematic representation shown in figure 1, position 1 is the cooling apparatus as a whole, which can represent, for example, fridge, freezer, freezer, air conditioning or any other device, mainly for domestic use, suitable for cooling a closed environment, in particular space 2, especially for food storage or for schools is by air in the living room.
The apparatus 1 includes a refrigerant circuit 3, the object of the present invention, which is suitable for implementing a thermodynamic refrigeration cycle and is suitable for moving a cooling fluid in a closed path according to the direction of movement indicated by the letter a in figure 1. Refrigerant circuit 3 operates on the basis of the phase transition of the liquid-vapor in the cooling fluid and includes a compressor 4, a condenser 5, a filter 18, the capillary device 6 and the evaporator 7, and in addition, other possible devices, suitable to improve the performance of the refrigeration cycle. Detailed description of the operation of the refrigeration circuit 3 goes beyond the content of the present invention and therefore not shown in detail.
The evaporator 7 is a first heat exchanger that performs the function of extracting energy in the form of heat from the inner part of the apparatus 1 and, in particular, from the space 2, and transmission cooling fluid that circulates through the evaporator 7. Space 2, which in the case of refrigerators are generally intended for food storage, or, in any case, perishable food products, is limited by the walls 8 and is accessible from the outside of the apparatus, for example, through one or more closed paths.
In more detail, the evaporator 7 includes a pipe 9 which extends from the first end 9a, attached (if necessary, through additional sections of pipe to the capillary device 6, to the second end 9b, which usually acts as a heat exchanger with a capillary device 6 attached (if required, also by using additional pipe sections) to the compressor 4. The pipe 9 is used to move the cooling fluid and provides the ability to transfer thermal energy (heat) from the space 2 of the cooling fluid circulating in the pipe 9.
Similarly, the capacitor 5 includes a coil 10, which passes from the first end 10A attached to the compressor 4 to the second end 10b attached to the capillary device 6, and which typically contains a filter element 18 for gas. The coil 10 is designed to move the cooling fluid and provides the ability to transfer thermal energy from the cooling fluid circulating in the coil 10, the external environment where the apparatus, or heat source.
If in a subsequent description is not specified, the coil 10 may consist of pipes, similar to the above-mentioned pipe 9, but with a smaller diameter, because of the higher operating pressures or, alternatively, it can be made of a metal pipe, as is usually the case at present in refrigeration circuits, to depict Alannah on the market.
According to current regulatory documents, the cooling fluid refers to classes qualification development Department (fluorocarbons), HC (hydrocarbons) or their mixtures. Preferably used cooling fluid is an aliphatic hydrocarbon, such as isobutane R600a.
According to the scheme depicted in figure 1, as the pipe 9 and the coil 10 are in accordance with the relevant winding trajectories (which, as an example, can form an angle equal to 180°, but can be applied to other equivalent workers geometric configuration, as better described hereinafter) and being curved with obtaining a compact configuration suitable for achieving effective heat transfer. Figure 2 shows an example embodiment of a pipe 9 of the evaporator 7, which is superimposed on the (lower or intermediate abutment surface 11 of the refrigerator and is represented using the thread-like scheme to highlight the winding path of the pipe 9. In more detail, the pipe 9 is built into the thickness of the surface 11 so that it is firmly connected with it, but, in the alternative, of course, it can also be placed inside the walls of the apparatus so that she was drowned in it. Preferably the pipe 9 made of a synthetic material, preferably plastic, to simplify the production ol the processes and to reduce the overall weight of the path.
Tube 9 must have at least four characteristics: it should provide a suitable heat exchange between the cooling fluid medium and cooling system and therefore should be of limited thickness; it should be impervious to current cooling fluid to prevent environmental pollution and loss of cooling capacity of the circuit, and it must also provide resistance to moisture/water resistant, to prevent seepage (and subsequent freezing of water in the cooling circuit; in addition, the pipe must also provide proof for O2and N2(non-condensable gases); and finally, the inner surface of the pipe shall be so shaped that when the passage of the gas had no sound waves of this nature, which are of concern to consumers.
The pipe 9 at least partially, and preferably completely or at least in the bends, is a corrugated pipe, profile type which is shown in figure 3. More precisely, from the outside, and preferably also inside the pipe 9 includes projections 12 and recesses 13, alternating with each other, which define essentially wavy outer profile, as shown in figure 3 and 4.
Mainly, this leads to increased turbulence when passing cooling the soup of the fluid, that improves the efficiency of heat exchange.
The study of the surface shape of these recesses 13 have shown that in order to avoid such turbulence, which causes sound waves (noise), which may cause concern to consumers, this surface should be flat, as shown in Fig. Other forms lead to the phenomenon of cavitation, which causes much annoying noise.
Preferably, the maximum outer diameter Dmax of the pipe 9, which is used for the evaporator 7 is from 6 mm to 14 mm, and preferably is in the optimal interval 8-11 mm, whereas the length of the pipe 9 to the evaporator is from 8 to 26 m depending on the desired heat transfer and hydraulic resistance.
In contrast, the optimal size of the refrigeration circuit in the condensing section (the first heat exchanger 5) the following: the maximum outer diameter Dmax of the pipe is in the range of 5-10 mm, preferably 6-8 mm.
This follows from the fact that the cooling fluid passing through the condenser is exposed to high pressures (condensed steam) and, thus, it requires a smaller cross-sectional dimension of the tube.
Pipe length is in the range of 4 to 15 m depending on the desired heat transfer and load losses.
The main feature of the refrigeration Contura is, in addition to providing the desired heat exchange, is the creation of a barrier, as far as possible, impervious to various substances.
The following is the substance and the typical limits for the application:
|Substance||The maximum allowable penetration||Unit|
|Oxygen+nitrogen||1%||The mole fraction, relative to the refrigerant, valid throughout the lifetime of the refrigerator (10 years)|
|Water||100 ppm (parts per million)||Mass fraction relative to the refrigerant, valid throughout the lifetime of the refrigerator (10 years)|
It is known that refrigeration circuits operate in the temperature range from -30°C to +70°C and in the pressure range from 0.03 to 1.2 MPa (0.3 to 12 bar); of course, the technical conditions for the tightness from the above table must be observed in all these intervals.
In addition, under normal operating conditions of the refrigeration circuit lubricating oil from the compressor partially and continuously araneida together with the refrigerant, in which it is completely soluble.
The oil has the properties of the refrigerant, i.e. the property of evaporation at a low temperature, and therefore the suction flow generated by the compressor, carries it around the refrigeration circuit, or in the form of a solution in the refrigerant, either in the form of drops, if the refrigerant has evaporated (in the evaporator).
To ensure the transportation of the refrigerant, the flow rate of the cooling fluid in the General case preferably should be above 4 m/C. If it is lower, there is a danger that the compressor may be deprived of oil, which will be captured in corrugated pipe, and it can burn.
Of course, this phenomenon imposes restrictions on the maximum cross-section of the circuit, which also depends on the type of corrugation. The issue of costs also impose restrictions on the maximum usable section.
On the contrary, for reasons connected with the heat transfer and hydraulic resistance, it is important that the maximum diameter of the cross sections of the refrigerant circuit was more than the above minimum values.
It is thus clear that the above intervals of sizes and geometric shapes are not just a design decision, and are the result of a compromise, which helps ensure compliance with all requirements applicable is passed to the refrigeration circuit.
Any deviation beyond the above-mentioned intervals lead to the failure of one or more technical requirements and to the impossibility of application of the refrigeration circuit in trade practices.
Pipe diameter, length and shape of the profile of the corrugation also have an impact on the occurrence of noise in the tubes as a result of the effect of turbulence and frequency of the vortices that occur inside the pipe itself.
On Fig shows the configuration of the pipe 9, where alternating projections 12 and recesses 13 define an undulating profile.
However, compared with the configuration shown in figure 3 and 4, each recess 13 in the cross-section includes at least one straight section 45, in particular, parallel or essentially parallel to the axis L of the pipe. In other words, the upper part of the recess 13 plusnut to ensure the passage of the fluid inside the pipe 9, while minimizing the phenomenon of cavitation and, therefore, minimizing the generation of noise.
Therefore, when the shirring and the choice of diameter is also necessary to consider this aspect and all aspects associated with the shape of a tube.
In a possible embodiment of the present invention to pipe 9 step p, i.e. the distance between two successive protrusions 12, preferably equal to 2 mm in Addition, the shape factor of the pipe, i.e. the ratio between the surface of the outer side phase the pipe 9 and the corresponding longitudinal length of the plot, may be from 20 mm2/mm to 60 mm2/mm
Mainly, the corrugated shape of the pipe 9 leads to an increase in the external surface of the pipe 9, as compared with a cylindrical tube having the same length, and thus facilitates heat exchange between the cooling fluid medium circulating inside the pipe 9, and the air outside.
In addition, mainly corrugated pipe profile 9 of the plastic makes it more flexible compared to the same cylindrical pipe, allowing bending radii and angles, which otherwise could lead to compression (reduction of the cross section for the adventures of the cooling fluid), and, thus, providing the ability to host according to a variety of different configurations by simply bending the pipe 9 without the occurrence of irreversible plastic deformation of the pipe 9. According to one embodiments of the present invention, which is not shown, the tube 9 may include only a few corrugated sections, in particular, only the areas to create a curved trajectory plots in the pipe 9, or areas where heat transfer must be maximum. In this case, the remaining parts of the tube 9, for creating straight lines, can be smooth or, in any case, the mod is but not to give a special form on their surface. In the case of smooth sections of the internal pipe diameter is from 4 to 11 mm, preferably 6-8 mm.
The pipe 9, mainly, can be produced by extrusion, by means of which receives a hollow cylindrical tube, which can be further modified using inline finishing to obtain the desired profile of the pipe 9. In particular, the extrusion may be followed by a stage of forming, on which the corrugated form shown in figure 3, only the hollow cylindrical object or only part of it. This can be achieved by connecting the outer side of the hollow cylindrical object with a matrix, the form of which the opposite Gavrilovna the profile that you want to receive, and create a pressure inside the object itself, so he forced plastic deformation shape opposite to the shape of the matrix. Preferably this phase of the exercise, when the hollow cylindrical object still has a high temperature corresponding to a condition suitable for the process of plastic deformation. Alternatively, instead of the internal pressure can create a negative pressure between the hollow cylindrical object and the sensor, to cause their mutual approximation and deformation of the hollow object, which takes the form of a matrix. The above OPE the policy formation causes that the tube 9 becomes corrugated profile both inside and outside, according to the image presented on Figure 3, and this gives it properties such as the aforementioned flexibility and the creation of turbulence in the cooling fluid circulating in it.
In addition to the round shape, as in figure 3, the cross section of the corrugated pipe can also have other geometric shapes, which contribute to the improvement of heat transfer. For example, in the freezer and the evaporator 7 is wound around the metal shelves. Metal (mostly aluminum) pipe, which is used at the present time, also usually has a round shape and therefore has a very small contact surface with the metal shelf, which you can specify a single line along the length of the pipe.
When using corrugated pipe, with corresponding effects on the cross section of the extrusion and form gamepress, you can get a D-shaped cross-section, depicted in Figa, which while retaining the flexibility required for winding the pipe around the shelves, allows to increase the heat exchange surface, as well as significantly improve the performance of the freezer and lower the cost.
According to the embodiment of the present invention, depicted in figure 4, the pipe 9 is obtained by multi-layer extrusion (co-extrusion), suitable for improving the Oia mechanical properties and impermeability of the tube 9. In fact, by multilayer extrusion can get the pipe 9, comprising two or more layers, each of which is chosen appropriately on the basis of special functions that it must perform, such as, going back to what has already been stated above, the proof for the cooling fluid, impermeability to moisture and non-condensable gases, flexibility, conductivity, and resistance to pressure, which exerts a cooling fluid medium.
According to the first requirement, the pipe 9 includes the first layer S1, usually external, is made from a material having properties that give the pipe 9 the necessary resistance to mechanical and thermal stress and tightness for the cooling fluid, which is usually used in the cooling apparatus for household purposes (hydrocarbons), in particular, R600a. Preferably this material is a polyamide grades 6; 6-6; 6-12; 11; 12 or one of the corresponding copolymers, preferably polyamide 6-6.
According to the second requirement, the pipe 9 includes the second layer S2, usually internal, made of material impervious to water and resistant to hydrolysis (i.e. to N2and O2and distinguished by good compatibility with the material of the layer S1. Preferably this material is a copolymer, for example, BynelŽ DuPont, such as BynelŽ 4206, low density polyethylene, modified maleic anhydride, or BynelŽ E, polypropylene, modified maleic anhydride. The second layer S2 are combined, i.e. overlapped with the first layer S1 to generate protection cooling fluid from any moisture or water from the outside, at the same time increasing the chemical inertness of the pipe in relation to the aforementioned cooling fluid environments.
In General, full thickness S of the pipe from the minimum to the maximum value is 0.4 to 1.5 mm and preferably ranges from 0.6 to 1.2 mm Thickness S1 of the material of the barrier for moisture and water ranges from 20% to 40% of the total thickness and is usually about 30%.
On the contrary, the thickness S2 of the material of the barrier for the cooling fluid and air is approximately 70% of the total thickness (typically ranges from 60% to 80%).
The thickness of the first layer S1 is from 0.2 mm to 0.4 mm, while the thickness of the second layer S2 is preferably from 0.4 mm to 1 mm
Alternatively, to lower the molar fraction of water in the circuit, you may need to search equilibrium conditions for the refrigerant circuit, which involve the use of different materials to balance water permeability between the condenser 10 and the evaporator 7.
Since the capacitor 10 operates at bolivia.com pressure (0.25 to 0.7 MPa (2,5-7 bar)), than the evaporator (usually 0.05 to 0.25 MPa (0,5-2,5 bar) - pressure 0.25 MPa (2.5 bar), the total for the evaporator and condenser is installed in a stationary circuit), the latter may consist entirely of polyamide-6,6 (RA material 6-6) or polyamide-12 (RA material 12 without the waterproof layer.
During operation of the compressor, the condenser provides a way out of the water received through the evaporator, thus maintaining equilibrium. This allows you to maintain the molar fraction of water within the outline below some critical value, which modern regulations set equal to 100 ppm (parts per million).
In a possible embodiment of the pipe 9, is depicted on Fig and 23, which are suitable for use as an evaporator and as a condenser, provides for the implementation of flexible corrugated pipe with a metallic coating to provide protection for flexible plastic tubes, with the addition of optimum barrier properties, which gives a metallic finish.
In particular, consider Fig, which shows a section of the pipe shown on Fig; first of all, it should be noted the presence of at least one of the inner layer 100 made of plastic, or from a thermoplastic material such as polyamide, for example polyamide-6,6 (PA 6-6).
The inner layer 100 of termoplastycznego material performs a structural function, i.e. function support and maintain the shape of the pipe (note that flexibility is ensured due to the presence of corrugated irregularities, i.e. the above-mentioned alternating projections 12 and recesses 13).
Also on Fig you can see the presence of a pinning layer 103, in particular a layer of adhesive located between a layer of 100 plastic and the subsequent layer 101 of the metal material, located above it.
Layer 103 adhesive acts as a binder for the metal layer, allowing to provide a strong accession of the latter to the layer 100 of structural thermoplastic material.
The metal layer 101 is typically flexible, i.e. it does not perform the function of supporting structure pipe 9 and, for example, may consist of a thin layer comprising or produced from a single layer or a multilayer film of metal material, such as aluminum, the thickness of which is approximately several micrometers.
You can also use, for example, the layer 101 consisting of two bases/metal films, inside of which there is the basis of the material that can retain its shape after deformation (for example, a material based on cellulose, such as paper).
Thus, the layer 101 can be subjected to mechanical deformation, to join the corrugated pipe and to maintain the connection to the deposition of the layer 102 of the outer cover.
The embodiment of the present invention, which can be taken in a non-limiting first solution includes a multilayer film type aluminum-paper-aluminium or single-layer aluminum film, which gives the proper form and keep on the pipe surface with a layer 102 of the coating.
You can also ensure the connection of the bottom surface of the metal layer 101 with an adhesive lacquer substance (or similar adhesive), which actually represents the specified layer 103.
This type of arrangement of the layers of the pipe provides simple and effective solutions to various problems, in particular in vaporizers, of which the first is the issue of excessive permeability for water vapor, only due to the properties of the metal layer.
Refer again to Fig which includes at least one layer 102 covering, which is preferably also made of plastic, to protect and/or fixing of the metal layer 101. Layer 102 covering completely covers the metal layer 101 and performs the additional function of securing the specified metal layer 101, and a function of the coating, providing increased protection from the effects of chemicals on the underlying metal, or electrical insulation between the aluminum if the volume 101 and the external environment.
In another alternative solution, the outer layer of the coating can be attached to the layer 101 and may be a heat-shrinkable material, so that the heating was shrinkage, thus causing the adhesion of the metal layer 101 to the outer surface of the corrugated pipe.
It should also be noted that the tube 9 (or section), as shown in Fig and 24, has a corrugated shape with a spiral course corrugation along the longitudinal axis L of the pipe.
On Fig shows a planar configuration of the recesses 13 of the corrugation, is configured to minimize the effects of cavitation and turbulence, which, in the absence of a flat shape, can cause noise, almost unacceptable to consumers.
It should also be noted that this configuration of the recesses can be applied in the pipe with the spiral shirring, and in the pipe with shirring of this type, as shown in Figure 3 or 4.
A method of manufacturing a pipe according Pig and 23 is as follows:
- carry out the extrusion and usually (though not necessarily) simultaneous shirring tube of thermoplastic material to obtain the specified spiral shirring.
The layer of adhesive 103 can either be formed by co-extrusion with the first layer 100 thermoplastic Mat is the Rial, or it can be applied on the inner surface of the aluminum film.
Then put a single layer or a multilayer film that contains or is made of one or more layers of metallic material (perhaps its surface is an external surface or both surfaces coated with an adhesive), and then through an extrusion put a plastic coating, the function of which consists in holding/fixing of the metallic coating (the above process becomes unnecessary when the aluminum film was previously coated with an adhesive).
In particular, the execution of the corrugated profile of the spiral shape allows you to automate the application of the metal layer.
It is obvious that a continuous coating with a metal layer on the corrugated pipe can significantly reduce production costs. In order to facilitate the bending of the metal film and its adhesion to the plastic surface 100, the film may consist of two or more band elements of the aluminum film, which after application to the pipe superimposed on each other to ensure their complete gas-tightness and, at the same time, perfectly adhere to the pipe. This situation is shown in Fig where the two tape metal element is marked as 101a (cover deepening of g is Mirovaya) and 101b (cover tabs corrugation) or Vice versa. In this case, there might also be the external coating 103 and the surface of the aluminum tape elements can be treated with an adhesive to glue them to each other and to the plastic. This configuration also provides more flexibility in the pipe. Using the method similar to that described above, a metal film or foil can be inserted into a plastic tube (Fig).
In this case, the film can be inserted into the plastic pipe during the extrusion process, by using, as a non-limiting example, the T-shaped extrusion head, and through the filing of a metal film (or tape) on the same line with the release of the plastic pipe.
The metal film can be combined with other metal or plastic films, preferably before applying such a way as to create a surface having the desired properties, such as a plastic coating on the surfaces in contact with cooling gas or the adhesive layer, providing the possibility of its connection with plastic pipe.
The metal film can also be used as resistance to defrost the evaporator.
In this case, it is applied a potential difference of such magnitude, to create a current which provides the heat, and the surface is rnost metal film put a layer of insulating coating.
Now back to the illustrative diagram, depicted in figure 1, where the top shows the filter 18, which is located between the first heat exchanger 5 and the capillary device 6 and is suitable for removal of water present in the circuit, for example, by use of the gel are able to absorb.
In contrast, the capillary device 6 includes a capillary tube 19 to reduce the pressure during the passage of a cooling fluid between the first heat exchanger 5 and the second heat exchanger 7. In addition, on its way it also function as energy recovery through heat exchange between flowing in it the hot refrigerant in the liquid state, and cold vapor, which is present in the pipe at the outlet of the evaporator 7.
This heat exchange is carried out in the so-called "pipe heat exchanger", which in an enlarged scale shown in figure 1.
To improve the efficiency of heat transfer for the same length of the pipe and, thus, with the same hydraulic resistance that is required in the capillary, it is possible to make the capillary tube cross-section which differs from the standard cross-section, depicted in Figure 5.
For example, at least part of the capillary tube 19, which carries out heat exchange, may be the external surface of larger area than the surface area of the pipe with all the cross-section; in this case, the cross section of the capillary tube 19 can include one or more petals to increase heat transfer.
"Radar" section depicted in Fig.6, and its main purpose is to increase the external surface of the pipe, through which the heat exchange with the cooling gas from the outside.
In fact, as can be seen in figure 1, at least one portion of the capillary tube 19 is always located inside the pipe 20 at the outlet of the evaporator 7 to provide an opportunity for energy recovery.
In addition, the pipe 9 (7, 8, 9, 10) includes narashima attached to the heating means 23 to provide the selective defrosting of the evaporator 7, when it is required.
In dynamic evaporators or evaporator with automatic defrosting (No Frost) function defrosting of the evaporator is carried out automatically by electrical resistance outside the loop.
This defrosting method is not very effective because it is based on the transfer of heat from the electrical resistance of the ice formed on the pipe, using radiation.
In the present invention the solution of the problem is the achievement of thawing of ice by means of a heating means 23, which narashima attached to the pipe 9 in a different way.
In the first embodiment the AI of the present invention the heating means 23 include at least one metallic conductor 24, as a non-limiting example, having a filamentary structure that is attached to the layer's pipe 9 (see Fig.7, 8, 9 and 10).
Usually a metallic conductor 24 is attached to the second layer S2 inside the pipe 9, as, in particular, its coextruding with this layer, and therefore it is at least partially sunk.
7 and 8 shows the presence of two electrically conductive wires, arranged in a widespread scheme essentially parallel to the longitudinal direction of the pipe 9.
In contrast, figures 9 and 10 show an embodiment in which the filamentary metallic conductor 24, is wound in a spiral around the longitudinal axis of the pipe 9.
In an alternate embodiment of the present invention (or, if required, in combination with the previous embodiment the heating means 23 include a conductive layer 25, formed on the surface, preferably on the outer surface of the pipe 9 (see Figa).
Such a conductive layer 25 can be implemented using various technologies, such as metallization surface of the pipe, which is carried by metallization in high vacuum, by applying a conductive nanoelements on the surface of the pipe etc.
Alternatively, you can apply a joint extrusion to create a thin layer of a conductive thermoplastic material, which performs a similar function.Alternatively, as the conductive element 25 can apply a metal film 101, as described above, in this case, it is necessary to pay attention to the fact that the applied potential difference provided enough heat to defrost the evaporator within the prescribed time, however, not exceeding the softening temperature of the material of the plastic pipe.
Drawing on the pipe coating from nanoelements can create an additional barrier for the flow of water in the refrigerant circuit, and also, due to the peculiarities of its surface may be a factor increasing the heat exchange with the air.
Usually there is at least one insulating surface coating 26 to protect the heating means 23 from the external environment outside of the pipe 9 (Figa).
In particular, this surface coating 26 can be obtained by applying an insulating polymer film, or using other methods of applying surface coatings.
Thus, the heating means 23 directly transfer heat required for melting the ice, from resistance, recessed into the tube, ice, thus significantly improving the efficiency of defrosting and reducing energy consumption.
It should be noted that the resistance of the aforementioned type are the flexible and thus, they do not reduce the ability to bend, typical for corrugated pipes.
Mainly, according to the embodiment of the present invention depicted in Fig, 18 and 19, the pipe 9 can be obtained by direct extrusion and embossing elements of different sizes, and by assembling two or more sections of pipe, preferably corrugated (Fig), but not necessarily corrugated (Fig)who are modular sizes. In other words, the pipe 9 can be obtained by mutual connection of two, and preferably many areas of the corrugated pipe, preferably having the same dimensions as the cross section and length. This allows you to get the pipe 9 of different lengths, at least, of the sites with the same standard length and, thus, suitable to facilitate proper storage. In this case, in fact, required only short range parts, stored, or, if required, only one type of pipe, which are then combined in sufficient quantity to produce a pipe 9 having a desired length.
As noted earlier, less expensive system in which the fixed connection can be obtained with the extrusion and continuous corrugation different parts of the refrigerant circuit using elements heromachine made according to different geometric forms.
Below is a description of some possible solutions for the Assembly of the various components of the refrigeration circuit.
The elements of the depicted compounds can be produced by alternative methods, such as vibration welding, laser welding etc; the purpose of these connections is to provide a mechanical connection and/or physical and/or chemical type, impervious to the cooling gas and other gases and moisture, as described above.
Typically, the circuit includes a set of connecting terminals or connecting elements 15 for mutual connection of multiple sections of pipe that are related to the refrigeration circuit, or to attach the pipe to the various components.
Figure 11 shows a possible embodiment of the connection between the capillary tube 19 and a corrugated tube 9 is related to the evaporator.
In particular, the connecting element 15 includes a slot 27, is suitable for the reception of the end 28 of the pipe 9; tightness between the connecting element 15 and the pipe 9 provide appropriate welding.
The connecting member 15 further includes a through channel 29, which allow passage of cooling fluid between the United pipe and by the connecting element. In particular, capillary tube 19 completely crosses above UTY through channel, delivering a cooling fluid medium directly in the input section of the corrugated pipe 9.
In order to ensure tightness between the capillary tube 19 and the connecting element 15, the latter includes a shaped landing area 31, is arranged to pass through it to the end of the capillary tube 19 to create in combination with the end region 30 of permanent connection. The connection preferably is received with the application of a suitable adhesive.
It should be noted that Fig shows the parts of the tubes of the heat exchanger, i.e. the portion of the tube where the inside of the pipe 9 is the capillary for the implementation of the above-mentioned heat transfer.
As can be noted, the connection in the left part between the connecting element and the section 21 of the pipe that contains the capillary, can be obtained by welding with the use of the above-mentioned slot 27 which receives the end 28 of the pipe 9, and welding technology.
In addition, the connecting element 15 includes an inlet/outlet 37 to enable transmission of the capillary tube 19 from the inside of the pipe 9 into the external environment and Vice versa (in this regard it should be noted that the entrance area of the capillary tube is a mirroring outlet, depicted on Fig, or has a different configuration).
Furthermore, it should mark the th the connection between the pipe of the heat exchanger and the return pipe from the evaporator includes an area of adhesive joints (pipe heat exchanger+capillary tube return tube), and a compound obtained by rotating welding (pipe heat exchanger with connection element).
On Fig shows a variant embodiment of the connection between the pipe of the heat exchanger and the return pipe from the evaporator: in fact, this connection only get through gluing.
In particular, shaped landing area 31 and the end of the pipe to form a preliminary connecting means 32, which provides the ability to pre-hold in place with the purpose of education subsequent permanent connection.
In particular, prior connecting means 32, shown on Fig includes corresponding protrusions 33 and recesses 34, appropriately located on the shaped planting areas 31 or at the ends of the pipe to provide a preliminary adhesion by planting, in which is stored the mutual position during subsequent stages of the formation of permanent connection.
During Assembly such protrusions 33 and recesses 34 are positioned relative to each other in such a way as to ensure the preservation of the state during the stages of education ner is zyemnogo connection (with glue welding and so on).
Pre-connecting means 32 of the same type can be used to connect successive sections of pipe directly with each other, as clearly shown in Fig.
Finally, it should be noted that in order to avoid the application of the connecting elements in the pipe of the heat exchanger, it is possible to apply the solutions shown in Fig and Fig, i.e. to create the inlet/outlet 37 in the specified pipe 9 to enable transmission of the capillary tube from an external environment into the pipe 9 and Vice versa. The tightness can be secured using an adhesive or welding.
On Fig depicts a variant embodiment of the present invention, where the inlet/outlet 37 create not normal shirring tube, and pre-shaped zone 38, suitable for a smooth area of the entrance/exit of the capillary tube, which is essentially parallel to the axis of the pipe.
Thus, it is possible to create a base surface and to provide a better bonding of pipes and leaks.
Thus, you only need to seal the capillary at the inlet and exit of the pipe and does not require additional processes.
Finally, on Fig shows the connection of metal pipes that are related to the path (for example, the inlet and outlet pipe of the compressor, indicated ssy is coy 35), with the pipe 9 in accordance with this invention.
In particular, the end of the pipe 9 superimposed on the corresponding end of the metal pipe 35 and is provided formed over the element 36 for the detachable connection of these ends.
In the preferred and illustrated embodiment of the present invention, only the evaporator 7 includes a flexible tube 9 is made of plastic, while the capacitor 5 includes traditional metal coil 10, which is welded to the rest of the refrigerant circuit 3. However, the device 1 may include both the coil 10 of the capacitor 5 and the pipe 9 of the evaporator 10 of synthetic material, preferably of one or more plastics of the type indicated above.
The present invention enables the achievement of objectives, eliminating the disadvantages mentioned in the prior art.
Use fasteners that are, in any case, are elements of the gap in the circuit and have some value, can be avoided when applying hiromachi greater length, equipped forming elements which form is suitable for various sections in the same continuously extruded corrugated pipe; the above section has a special form, for example, required for connection to copper pipe (35), can be obtained by continuous extrusion and who compete with profiled elements end pipe sections. In the same way, it is possible to continuously ekstradiroval pipe 17 of the heat exchanger together with the pipe 9 of the evaporator 7 by inserting in heromachine if you want profiled elements for obtaining section 38 for insertion of the capillary 19 and the end section 36 for covering the moulding. Thus, it is possible to avoid the application of multiple couplings, which makes refrigeration safer and less expensive.
The presence of the flexible tube provides a very simple and flexible installation pipes in household appliances, because it is not necessary to determine in advance the configuration of the pipe, but the pipe bend differently in an optimal way, depending on the spatial requirements and form the coated surface of the heat exchange.
Corrugated tube shape at least in some areas can increase the heat exchange surface, because the corrugated pipe has a large external surface than the corresponding smooth or, at least, perfectly cylindrical pipe. In addition, the corrugated shape of the inside of the pipe provides the possibility of vortex motion in the cooling fluid, which has a positive effect on heat transfer carried out by the fluid medium.
The capillary device 6 and the pipe piece 17 of the heat exchanger form a Tr is boaty the heat exchanger, which includes an inner tube calibrated polyamide pipe, where flows the fluid to be cooled, and an outer pipe, if required, obtained by joint extrusion with the inner pipe (Figa, 14b), or rolled or obtained by joint extrusion/rolled pipe (Fig C) outside or inside the pipe 17, in which there are pairs that are subject to heating and subsequent compression with a compressor, without drops. The above-described device, the required form can be made entirely of plastic, unlike the devices of the prior art with the use of metals, which for obvious reasons limiting its shape and length.
As indicated, the pipe 17 can also be obtained by a simple extension pipe 9 of the evaporator 7, thus eliminating the connection.
In addition, as such a device, and the various components of the refrigeration circuit, conveniently manufactured using co-extrusion plastic with inserted at one or more thin metal wires, which are used as resistance for rapid defrosting of the evaporator or any other part of the circuit or overheating of the steam, which is sent to the compressor.
So, in other words, if you want, (even regardless of the corrugation of the pipe or areas of such resistance elements (p is boloco of metal or conductive material) can be repaid in specified areas of the pipe for defrosting or heating one or more portions of a path.
Alternatively (or in combination), you can provide the application to the pipe or its parts, manufactured using co-extrusion, one or more layers of plastics, coatings of special varnish (optional outer layer)containing conductive nanoelement; this varnish can be applied by spraying during extrusion or later already assembled product or, alternatively even by immersion in a special bath; this varnish has the property to generate heat by passing electric current to perform the function of the device for defrosting or heating device for special zones cooling loop.
The capacitor 10 can be made by analogy with those described for evaporators 9, by making the most appropriate possible way of plastic pipes such shapes and sizes to match the technical requirements of the cooling devices.
Capacitors 10 working before the compressor must operate at a higher pressure than the pressure in the evaporator 7.
For this reason, they must meet more stringent rules, in particular, they must withstand high pressure up to 3.6 MPa (bar 36).
For this reason, the thickness of the corrugated pipe shall be increased to not less than 0.7 mm (preferred is part of 0.8-1.4 mm) and thus, it is important to increase the heat exchange surface, making them suitable geometric shape.
All of these circuit components can be connected with each other by using the above-mentioned connecting elements, which saves costs of Assembly (currently, they are welded to each other) and to increase the reliability of the Assembly.
Connections between the components of the refrigerant circuit (evaporator, capillary, tube heat exchanger, compressor, condenser and filter) can be set using the operation of rotary welding or bonding using high-speed connections with seals (o-rings or alternative seal) as the sealing element.
You can also create profiles on the corrugated pipe, to provide a snap connection and create a socket for accommodating a sealing binder or a special sealing element, such as o-ring of suitable material (Fig) with the placement of the adhesive 40 for sealing the space between the two sealing elements 42 and 43. Glue can enter through the hole 41 (may require two symmetrical holes for air release).
In addition, it should be noted that the particular shape of the capillary seems advantageous in itself, regardless of n is the availability of corrugated plastic pipes; also described above, the connecting elements themselves suitable for use, regardless of corrugated plastic pipes.
Thus, in the described invention excluded complicated and expensive methods of manufacturing metal pipes and flexible for traditional metal evaporator coil and reduced range of products in storage, since it is necessary to store only the pipe, which is not yet attached to the end winding and curved shape. In addition, you can easily eliminate the need to store tubes in the presence of technological lines for the extrusion and embossing plastic pipes, which cost at least 20 times lower than the cost of the technological line for production of metal pipes, and occupy far less space required for a process line for manufacturing a metal pipe.
Manufacturer of plastic pipes, in particular by extrusion or co-extrusion, dramatically reduces the cost of the starting material required for the manufacture of the various components of the refrigeration circuit, and greatly simplifies the manufacturing processes of the pipe, followed by a sharp decrease in the cost of production of household appliances. In addition, it allows to significantly reduce the mass consumer PR is boron resulting from the replacement of traditional metal coil on the coil is made of plastic.
The possibility of receiving tubes of the modular sections of the pipe is further facilitated by the store, because you can provide only a few types of sections of pipe with specified lengths and cross sections.
The pipe connection with the rest of the refrigeration circuit no longer requires the traditional welding, which, in addition, that requires the use of special equipment and mainly carried out manually, is irreversible and, therefore, not provide the ability to retrieve pipe from appliances.
The presence of fast-acting connecting elements, the application obtained by joint extrusion of pipes, which act as heat exchangers, and the ability to interchange parts straight and rigid pipe corrugated parts that are bent, as required, provides the ability to create different profiles and cross sections in refrigeration circuits, which opens up new prospects for the design, functionality and performance of the circuits.
Also in this case, when there are special hiromachi, it is possible to make different sections without gaps that require connections. For example, the pipe 5 of the capacitor can be shared to ekstradiroval with the pipe 10b and, in the presence of special items in heromachine, you can get GN is healthy for the filter 18 in the same way, without the use of connecting elements, with the gains in efficiency and reliability, as described above (Figa and 21b).
There are additional advantages, such as corrosion resistance, less porosity of the surface, which impedes the adhesion of ice to the surface, the ability to reuse materials used for the refrigerant circuit, without the need for costly separation of the components; these benefits contribute to improving the competitiveness and profitability of the proposed technology compared to today's technology.
1. The refrigerant circuit (3) for household appliances, in particular household appliances for refrigeration, such as refrigerators and freezers, including:
at least one first heat exchanger (5)is made with the possibility of hydraulic messages compressor (4), which provides cooling through the cooling fluid and its transition essentially in the liquid phase;
at least one second heat exchanger (7), hydraulically connected with a first heat exchanger (5) and working in space (2)subject to cooling; the specified second heat exchanger (7) provides at least partial passage of the cooling fluid in the gaseous phase with the absorption of heat by che is cooled on the specified space (2); moreover, the cooling fluid circulates from the first heat exchanger (5) to the second heat exchanger (7) and, thus, enters the compressor (4) for the next cycle, and
- capillary device (6)located between the first heat exchanger (5) and second (7) heat exchanger for expanding the specified cooling fluid, and at least one of the first heat exchanger (5) and the second heat exchanger (7) includes at least one flexible pipe (9), characterized in that at least one specified area of the pipe (9) has a corrugated profile, which gives it flexibility, and the said pipe (9) in the cross-section includes at least one layer (100) from plastic and at least one layer (101)comprising a metal material, and the metal layer (101) is connected with a layer of plastic, and the metal material is made with the possibility of formation of a barrier against moisture; and the specified layer (100) of plastic material is a layer, the structural purpose of which is to preserve the shape of the pipe (9), and preferably made of a thermoplastic material; however, the specified metal layer (101) is flexible, does not act as the supporting structure and includes a single-layer metal film or a multilayer film including one sludge is some metal films
connected or not connected with the layer of material is configured to maintain the shape.
2. The circuit according to claim 1, characterized in that the pipe (9) includes at least one layer (102) of the coating, preferably of plastic material and may consist of heat-shrinkable film, for protecting and/or fixing a metal layer (101).
3. The circuit according to claim 1, characterized in that the tube (9) includes at least one corrugated profile with a spiral course corrugation along the longitudinal direction of the pipe.
4. The circuit according to claim 1, characterized in that the corrugated pipe profile in cross section includes protrusions (12) and the recess (13), alternating with each other, and the said recesses (13) include at least one straight section (45), passing preferably essentially parallel to the axis L of the pipe (9).
5. The circuit according to claim 1, characterized in that the pipe (9) further includes a connecting layer (103), preferably, the layer of adhesive located between the layer of (100) plastic and a layer (101) of metal material, for the mutual connection of the two layers (100, 101).
6. The circuit according to claim 1, characterized in that the layer (100) plastic is a polyamide, such as polyamide-6,6 (PA 6-6).
7. The circuit according to claim 1, characterized in that the metal layer (101) is completely covered with a layer (102) p the closure, which provides reinforcement and chemical protection of the metal layer.
8. The circuit according to claim 1, characterized in that the layer of material is made of paper material.
9. The circuit according to any one of the preceding paragraphs, characterized in that the metal layer (101) consists of two or more metal tape elements (101a) and (101b), overlapping in the longitudinal section of the pipe (9) from the respective edges, and, preferably, a metal layer (101) or tape elements (101a) and (101b) pre-treated so that they include a layer of adhesive to one or both of the upper and lower surfaces.
10. Pipe for refrigerant circuits for household appliances, in particular household appliances for refrigeration, such as refrigerators and freezers; characterized in that a represents a flexible tube and includes at least one layer having a corrugated profile, able to give it flexibility, and the fact that this pipe (9) in the cross-section includes at least one layer (100) of a thermoplastic material and at least one layer (101)comprising a metal material, coupled with a layer of thermoplastic material, and the layer (101) is arranged to education barrier against moisture; and the specified layer (100) is a layer, the structural assignment is otorongo is to preserve the shape of the pipe (9), and preferably made of a thermoplastic material; however, the specified metal layer (101) is flexible, does not act as the supporting structure and includes a single-layer metal film or a multilayer film that includes one or more metal films, connected or not connected with the layer of material is configured to maintain the shape.
11. A method of manufacturing pipes for refrigerant circuits for appliances, characterized in that it comprises the following stages:
- extrusion of plastic pipes and stage extrusion process preferably includes a step co-extrusion layer (100) of a thermoplastic material, and possibly overlying layer (103) adhesives, acting as a binder;
- shirring at least one specified area of the pipe, and, preferably, stage corrugation is a stage corrugation with a spiral course corrugation along the longitudinal direction of the pipe, more preferably, extrusion and shirring takes place simultaneously;
- application layer (101)comprising a metal material, corrugated pipe, and the specified layer (101) is made with the possibility of formation of a barrier against moisture.
12. The method according to claim 11, characterized in that it further includes a step will complement the school extrusion layer (102) of the coating, preferably, made of plastic, to protect/secure layer (101)comprising at least one film of a metal material.
13. The method according to claim 11 or 12, characterized in that the layer (101)comprising a metal material injected during extrusion plastic pipe (100)which is subject to shirring, and ensure its adhesion to the inner wall by means of a hydraulic or mechanical system located inside heromachine, or directly behind it, this layer corresponded to the corrugated shape of the pipe, and a layer (101)comprising a metal material, preferably, includes an adhesive layer (103) on the surface to be joining the pipe.
14. The method according to claim 11 or 12, characterized in that the inner surface layer (101) of the metal material in contact with fluid medium applied plastic coating (102)obtained previously.
15. The method according to claim 11, characterized in that the metal film within the required time intervals, apply a potential difference to create an electric current of suitable magnitude for the specified heating the film to a temperature not exceeding the melting temperature of the plastics from which the formed pipe, but sufficient for melting ice formed on the pipe.
16. The method according to claim 11, characterized in that studyhomepage includes the operation of the alignment recesses (13), to create a flat inner surface inside the pipe to prevent noise caused by the flow of gas inside the tube.
SUBSTANCE: invention refers to heat power engineering and can be used at manufacture of boiler tubes. A production method of boiler tubes with different inner ribbed surfaces consists in the fact that a spindle calculated as per dimensions and provided with a pass having the specified shape of outer surface is made with coiling into the pass of a wire-like element forming on it a reverse image of the specified ribbed structure of a tube. A brazing metal paste is applied onto outer surface of the wire-like element and the spindle is introduced into the tube. In order to provide adaptation of the wire-like element to inner surface of the tube, the spindle is removed from above wire-like element and the tube is heated up to fusion temperature of the brazing metal paste to connect the wire-like element to inner surface of the tube, and then, the tube is cooled.
EFFECT: simpler formation, introduction and fixation of ribs inside the tube.
10 cl, 5 dwg
SUBSTANCE: for the purpose of water heating by solar radiation, a heat exchange panel with absorbing coating is put in a heat insulated casing with the glass through which the sun light reaches the surface of the panel, heats it and an attached pipe with a heat carrier, the heated heat carrier is delivered by the said pipe to the accumulation tank of a user. The heat exchange panel and method of its assembly comprises elements made from aluminium profiles with a heat carrier pipe being inserted in them, the flat surface of the aluminium profile of the heat exchange panel is fitted by V-shaped longitudinal grooves 0.5 mm wide and deep with the pitch between the centres of 10 mm and is coated by heat-proof paint diluted by a solvent, and the aluminium profile elements are made on the opposite sides with the edges forming a closed loop around the heat carrier pipe when one element is jointed with another, being a part of heat conducting section of the panel and ferruling it due to some structurally specified tension. Circulation of the heat carrier in the loop provides for the accumulation of hot water due to cooling of the heat exchange panel. For the purpose of maximal efficiency of the process it is necessary that the heat exchange panel is of minimal heat capacity but at the same time transfers heat to the heat carrier as fast as possible. The above is implemented in the proposed invention by manufacturing of the heat exchange panel from the material with good thermal conductivity - aluminium - and by the optimisation of the panel's heat conducting section for better heat contact with the heat carrier pipe.
EFFECT: profile has no additional surfaces not engaged in heat exchange process, maximal heat transfer to the heat carrier pipe is ensured due to the fact that it is closely embraced by one profile side and closed by another side with provision for necessary pressing.
FIELD: power industry.
SUBSTANCE: in a heat exchanger pipe, smooth pipe sections and ledges form a channel, where ledges feature additional heat exchanger intensifier in the form of discreet slots perpendicular to flow, and the channel matches geometry relations: l2=(90-100)h; l1=(90-100)h; l'/l1=0.05; h/D=0.03, where l2 is slot length, mm; l1 is ledge length, mm; l' is length of ledge section between shallow slots, mm; h is ledge height, mm; D is inner diameter of heat exchanger pipe, mm.
EFFECT: enhanced power efficiency due to reduced flow friction.
4 dwg, 1 tbl
SUBSTANCE: in a heat exchange tube, the channel of which has projections and grooves, according to the proposed invention, the channel is formed with plain tube sections and narrow grooves with geometrical ratios: h/D=0.1, (t-l)/h=1, l/h<(3-5) where h - projection height, mm, D - inner diameter of the heat exchange tube, mm, t - length of a typical section of the channel with a projection and a groove, mm, l - groove length, mm.
EFFECT: use of the proposed heat exchange tube will allow reducing consumption of energy for pumping of heat carriers through a heat exchange unit by 2,5-4 times in comparison to a plain-tube heat exchange unit owing to reducing hydraulic resistance.
4 dwg, 1 tbl
SUBSTANCE: double-pipe heat exchanger, in the internal pipe and in inter-pipe space of which screw inserts are installed. Inner space of the internal pipe and inter-pipe space between internal and external pipes represent screw cavities formed with walls of pipes and screw inserts. Screw inserts are installed so that an internal screw insert is connected mainly by welding or soldering to inner surface of the internal pipe. Screw insert in inter-pipe space is connected in the same manner to outer surface of the internal pipe and to inner surface of the external pipe. Materials of the internal pipe, screw inserts and points of joints of screw inserts with walls of the internal pipe shall have minimum thermal resistance. Flows of liquid or gaseous media in the internal pipe and in inter-pipe space flow along helical spirals.
EFFECT: invention allows shortening the length of double-pipe heat exchangers up to ten times and more and reducing the weight and overall dimensions of a heat exchanger.
SUBSTANCE: double-pipe heat exchanger for liquid and gaseous media, which contains a heat exchange pipe and an external turbulence promoter dividing inter-tube space into inlet and outlet cavities, which are concentrically located in the cylindrical housing. On the turbulence promoter surface there are the holes serving as medium injection to the cavity between the heat exchange pipe and external turbulence promoter. Inside the heat exchange pipe there concentrically located is an internal turbulence promoter dividing inter-tube space into inlet and outlet cavities and having the holes on the surface, which serve as medium injection into the cavity between the heat exchange pipe and the internal turbulence promoter. Use of the invention will allow intensifying heat exchange due to almost complete removal of a boundary layer from outer and inner surfaces of the heat-conducting pipe with heated (or cooled) medium.
EFFECT: increasing heat transfer coefficient between heat carrier and heated medium up to 10 times and more; reduction of the required heat exchange surface corresponding to it, length of stream heat exchangers, their weight and overall dimensions.
FIELD: power engineering.
SUBSTANCE: heat exchanger comprises a vessel with the first and second channels for coolants and spherical heat transfer elements placed in spherical holes. Channels are separated with a heat transfer surface, inlet and outlet nozzles of the first channel, inlet and outlet nozzles of the second channel. Spherical heat transfer elements are placed in spherical holes on the heat transfer surface and on the inner surface of the vessel.
EFFECT: invention makes it possible to improve heat transfer from a heat transfer surface that separates channels of a heat exchanger.
FIELD: power engineering.
SUBSTANCE: heat exchange pipe, in which a channel is made with protrusions and grooves, besides, the channel is made with geometric ratios: h/D=0.03, l1=(90-100)/h, l2=(90-100)h, where h - protrusion height, mm D - inner diameter of a heat exchange pipe, mm l1 - protrusion length, mm l2 - groove length, mm.
EFFECT: invention makes it possible to increase energy efficiency due to reduction of hydraulic resistance.
FIELD: power industry.
SUBSTANCE: tubular heat exchanger includes tubes with ribs. Tubes pass in some axial direction and are equipped with heat exchange ribs. Each rib includes a heat exchanger surface that envelopes a tube and passes in some radial direction relative to the tube and has relief shape, thus forming grooves located at some distance from each other in radial direction. Grooves of a rib have dimensions, such as width and depth, which are reduced as far as they are located at some distance from the tube in radial direction, thus providing direction of fluid medium around the tube.
EFFECT: creation of a shaped rib structure for a heat exchanger tube, which allows increasing heat exchange between air and fluid medium circulating in the tube without deterioration of head loss.
9 cl, 10 dwg
SUBSTANCE: heat exchanger contains pipeline made in the form of wall of a through cavity with outer surface and end sections. Also it contains external heat transfer elements attached to one end section. Wall of the through cavity of another end section is made in the form of an enveloping element of a through opening that is formed in the wall of the room. At that external heat transfer elements are made in the form of facing elements of the wall of the room being made from steel plates, pipes, channel sections, angle elements or bars. End sections are fastened to each other by metal fixing device.
EFFECT: improving efficiency of heat transfer from heat exchanger to ambient air enlarging functional capabilities of heat exchanger and the number of hardware.
SUBSTANCE: invention refers to refrigerating unit (1) that includes external housing (2), at least one refrigerating compartment (3) for storage of cooled products (5) and refrigerating circuit (6) with evaporator (4) for cooling of refrigerating compartment (3). Evaporator (4) includes the first element (7) of evaporator and the second element (8) of evaporator; besides, the first element (7) of evaporator is located outside refrigerating compartment (3), and the second element (8) of evaporator is located inside refrigerating compartment (3). The first element (7) of evaporator is made in the form of a helix evaporator, envelops refrigerating compartment (3) and includes the pipelines carrying cooling agent, which are wound around the refrigerating compartment and are in heat-carrying contact with it. The first element (7) of evaporator and the second element (8) of evaporator are connected in series; besides, the cooling agent circulating in refrigerating circuit (6) of the refrigerating unit first flows through one evaporator element, and then through the other evaporator element, or they are parallel connected.
EFFECT: increasing efficiency, and cooling or freezing capacity.
6 cl, 1 dwg
SUBSTANCE: invention refers to refrigerating device, in which there installed is evaporator with anti-icing device (4) intended for elimination of ice accretion on tube (3) for cooling agent and/or heat exchanger (2); with that, the above heat exchanger (2) includes tube (3) for cooling agent with expansion point (3.3) having an increasing diameter; at least one branch pipe (3.1) of small diameter and one branch pipe (3.2) of large diameter is connected to heat exchanger (2). Property of invention is that in comparison to front section of tube (3), the above anti-icing device (4) in section to inlet element (3.2.1) of heat exchanger is approximated to branch pipe (3.2) of large diameter and preferably to expansion point (3.3).
EFFECT: effective elimination of evaporator icing.
8 cl, 3 dwg
FIELD: machine building.
SUBSTANCE: cryogenic liquid evaporator includes a housing with cooling agent inlet and outlet chambers, heat exchange elements containing a liquid cooling agent chamber and a central tube equipped with an ejector. Cooling agent inlet and outlet chambers are divided with a partition wall with a hole, heat exchange elements are installed in the partition wall and interconnected with the central tube; the central tube is installed into the hole made in the partition wall with a gap, and the ejector has an insert that controls gaseous cooling agent from liquid cooling agent chambers. Cryogenic liquid evaporator is equipped with a recuperator. Evaporator allows increasing cooling agent use efficiency due to repeated use of cooling agent and arrangement of two-stepped cooling of working substance.
EFFECT: absence of any additional heat source for evaporation of liquid cooling agent and absence in the design of massive heat exchange head pieces additionally increases evaporator operating efficiency and reduces hydraulic resistance of an evaporator.
1 cl, 3 dwg
FIELD: machine building.
SUBSTANCE: invention describes evaporative device (1) designed for obtaining ammonia and use of device (1) in mobile exhaust gas outlet systems; device (1) includes housing (2) with at least one supply pipeline (3) and at least one discharge pipeline (4), in which there provided is at least one heating element (5) and at least one channel (6) for connection of supply pipeline (3) to discharge pipeline (4), and in which at least one heating element (5) is in heat-conducting contact with evaporative section (7) of at least one channel (6), and at least one channel (6) is made on that evaporative section (7) in the form of meander (8). Besides, evaporative section includes at least one tube that is rigidly attached to the housing.
EFFECT: invention differs by compactness and allows obtaining gaseous ammonia with the specified accuracy and completeness.
16 cl, 11 dwg
SUBSTANCE: invention refers to a refrigerating device with a cooling agent circulation system that includes a cooling agent compressor, a condenser, an evaporator with an evaporation plate for heat energy transfer from a refrigerating compartment of the refrigerating device to the cooling agent circulation system, and a temperature sensor for determination of evaporation plate temperature through sensitive surface of temperature sensor, which is connected to the evaporation plate by means of a holder. Holder is made so that immediate contact of sensitive surface of temperature sensor to evaporation plate of the evaporator that is located inside the refrigerating compartment is provided.
EFFECT: use of the present invention allows improved determination of evaporation plate temperature.
10 cl, 5 dwg
FIELD: electrical engineering.
SUBSTANCE: refrigerating apparatus is designed with at least one storage box cooled by an evaporator in the form of a plate and one refrigeration circuit containing such evaporator in the form of a plate. The channel (1) for the evaporator cooling medium is divided into at least two pipeline branches (4, 5) that cool the storage box, are included into the refrigeration circuit in parallel and have gravity centres (9, 10) distanced from each other.
EFFECT: distance between the gravity centres exceeds the ratio of the evaporator surface area to the length of the channel laid along the said evaporator; the invention usage will allow to reduce the refrigerator energy consumption.
9 cl, 2 dwg
FIELD: power engineering.
SUBSTANCE: invention relates to a valve unit (1), comprising an inlet hole, a distributor and an outlet part having at least two outlet holes. The distributor comprises an inlet part (5), communicating with the specified inlet hole, and is made as capable of distributing fluid medium received from this inle thole, between at least two parallel flows of a heat exchanger (3). The valve unit (1) also comprises the first valve unit and the second valve unit installed as capable of displacement relative to each other so that mutual position of these valve elements determines the fluid medium flow passing from the inlet hole to each outlet hole of the outlet part. Besides, the valve unit (1) comprises a collector (2) forming an integral part of the valve unit (1). This collector (2) is made as capable of forming a zone of coupling with a heat exchanger (3), having at least two channels, at the same time this collector provides for such liquid communication, at which every outlet hole (7, 9) communicates with the channel of the heat exchanger (3), connected to the collector (2). The collector comprises at least one separating element that separates at least two sections of the collector, besides, each of these sections communicates with the distributor and the specified zone of coupling with the heat exchanger.
EFFECT: using the invention will make it possible to improve distribution of a coolant between heat exchanger channels.
13 cl, 11 dwg
FIELD: instrument making.
SUBSTANCE: refrigerating unit is proposed with an insulated inner space, where at least one cooled part installed, the surface of which is prone to icing. According to the invention, onto surfaces prone to icing a coating is applied, which contains organic substances preventing growth of ice crystals or limiting it.
EFFECT: using this invention makes it possible to reduce power consumption.
6 cl, 2 dwg
FIELD: power engineering.
SUBSTANCE: cooling element for cooling of air passing through it under gravity, comprising multiple cooling discs installed in the form of an array to form gaps between them, stretching vertically and designed for flow of cooled air, besides, cooling discs reaching to the side, which is an inlet side for cooled air, alternate with shorter cooling discs, which do not reach the specified input side, so that air flows from wider gaps into narrower ones.
EFFECT: expanded arsenal of facilities for cooling of various objects.
4 cl, 2 dwg
SUBSTANCE: invention relates to agriculture. The proposed milk tank truck comprises the following components fixed on a single frame of the milk tank truck - a heat insulated elliptical reservoir 1 with an upper hatch 4, a tight cover 5 and a drain nozzle, a deep-rolled slot bottom evaporator 9, a gear motor 6 with a mixer 7, a compressor-condenser device 13. The deep-rolled slot bottom evaporator 9 is arranged with seam welding with longitudinal channels and a turning cavity 10, an injector 11 and a suction collector 12. A suction pipeline 19 of the compressor-condenser device 13 is connected to the upper part of the collector 12, the injection pipeline 13 of the compressor-condenser device 13 - with the lower part of the injector 11.
EFFECT: invention simplifies the process of milk cooling, maintains its optimal temperature for a long period of time.
2 cl, 2 dwg