Method and device for preheating of compacted material mat in production of particle board

FIELD: process engineering.

SUBSTANCE: invention relates to preheating of material laid over continuous circulating moulding mat belt in production of particle boards. For preheating of mat material on one or both sides microwave radiation is introduced therein. Material mat is compacted and hardened after feed into continuously operating extruder at definite pressure and temperature. For heating said mat microwaves in frequency band of 2400-2500 MHz are used. Said microwaves for every surface of said mat are generated in 20-300 microwave generators with 3-50 kW magnetrons each. Used heater is composed of continuous operation through-type furnace. 20-300 microwave generators with 3-50 kW magnetrons are arranged inside the furnace on every side to operate in 2400-2500 MHz frequency band.

EFFECT: higher efficiency of heating.

25 cl, 3 dwg

 

The invention relates to a method of pre-heating is covered with an endless continuously circulating molding carpet tape moldable material in the manufacture of chipboard under the restrictive part of paragraph 1 of the claims, as well as to a device for preheating is covered with an endless continuously circulating molding carpet tape moldable material in the manufacture of chipboard under the restrictive part of paragraph 15 of the claims.

From the patent literature and in industry it is widely known application of high-frequency technology as a means to pre-heat the particle, respectively, of the fibrous material to reduce the degree of compaction during running then pressing process in order to improve performance. From US 4 018 642 And know the use of microwaves as a source of thermal energy for the manufacture of plywood, fiberboard, chipboard and waffle plates, and the traveling wave purposefully through the so-called rectifier waves with a frequency in the range from 100 to 10000 MHz is sent to the pressed material. In this patent US 4 018 642 discussed mainly preheating and alkaline curing resins and similar is cnyh adhesive compositions. Efficiency is usually less than 50%. Thus, it is not economically feasible to use this type of heating for the complete curing of the Mat of pressed material, but only for pre-heating of bulk and if necessary, compacted carpets moldable material. Significant problems and dangers of high frequency heating does not necessarily consist in ensuring uniform heating of the Mat of compressible material, the difficulties of regulating the applied high frequency energy and emerging breakouts. To overcome these difficulties in DE 21 13 763 B2 describes measures for targeted seal between the zones of influence of microwaves.

Device for the manufacture of chipboard or laminated wood stove, veneered, also known from DE 197 18 772 A1 or DE 196 27 024 A1. These devices have long been in the industry successfully perform preheating of compressible material (carpet moldable material, pieces of compressible material) with the help of microwaves. In particular, this technology is well-proven in the way of making a very thick chipboard, respectively, of laminated wood panels, veneered with thickness up to 150 mm, economical manufacture of which no device before alternova heating is impossible. At the same time as units for microwave pre-heating is used in most cases, continuous furnaces. Because the manufacture of chipboards the plate width several times greater than the thickness of the plates, microwaves radiate perpendicular to the plane of chipboard. The width of the plates is between 1200 mm 3900 mm, and the thickness of 30-150 mm, the Creation of microwaves is carried out in a microwave generators, which are high-frequency modulators and magnetrons. Due to the large power consumption of microwave radiation device for preheating requires multiple generators, which are in most cases the output power 75-100 kW each and placed in locked electrical premises near the manufacturing facility. From there the generated microwaves using hollow waveguides are routed to the actual heating cell production plant, for each generator required the hollow waveguide. To achieve the most uniform distribution of heat in passing moldable material supplied through hollow waveguides microwave coming from the individual generators, branched and thus the number of conductive energy hollow waveguides increases, due to what is you can implement dense raster supply top and bottom heating of the cell. Normal now is branching 1 to 2, i.e. coming from the four generators of the energy supplied first with four waveguides, and then is divided into eight waveguides, which are 8 input. Enter in the heating cell is carried out using hollow waveguides of circular cross section, which are located vertically under the heating cell and above it. For each input you want the device measurement and control, which adjusts the phase position of the microwaves. The investment costs for such a device pre-heating using microwaves is very large, and thus have been successfully used to date only in installations for the production of laminated wood panels, veneered.

In DE 101 57 601 A1 disclosed a device for heating moldable material using microwave energy, which should reduce investment costs, increase operational availability and reduce management costs. This problem is solved by the fact that the microwave preheating device consists of made in the form of continuous furnaces heating of the cell in which the input of the microwaves in the pressed material through arranged one after another whip antennas with a reflective screen, which is recovered horizontally and transversely to the direction of work on the compression of the material and/or under him in a heating cell, when the whip antenna is aligned with the reflective surfaces lying opposite surfaces of the compression of the material. The supply of microwaves can again be realized from the generators to the heating cell using hollow waveguides in fact, due to the characteristics of radiation whip antenna, as a rule, there is no need to fork coming from the generators hollow waveguides, i.e. the number of input corresponds to the number of generators. To pass from the hollow waveguide to the whip antenna used was developed actually for this waveguide transitions. Although this type of pre-heating in principle spread, however it still has drawbacks regarding the amount of occupied constructive space and a large selection of power in the individual structural elements.

From practice and patent literature known following ranges of high frequency and microwave for a given industrial application. Usually there is a frequency below 300 MHz is considered as high frequency, the frequency from 300 MHz to 300,000 MHz as microwave frequency.

In DE 694 19 631 T2 is applied a high frequency of 13.56 MHz at a power of 8 kW. In DE 44 12 515 A1 specified operating frequency 21,12 MHz or 13.56 MHz.

Of CA 2 443 799 WITH known microwave heating frequency of 915 MHz, if e is ω here microwaves are introduced directly into the input slot (the area of narrowing the press area at the entrance continuously operating press) carpet moldable material. Along with a very complex structure revealed problems due to uncontrolled reflections from the steel belts.

In principle in the prior art there is no specific guidance regarding the optimal frequency range due to the necessary power consumption, respectively, of the radiation power and in connection with the required number of generators to heat passing a given speed of the Mat of compressible material with different properties. Usually in the patent literature indicates that the exact implementation of the microwave device for one or the other method chosen specialist (on-site), specify the frequency is limited to the range microwaves or provide guidance values several orders of magnitude. On the basis of such data, the specialist does not receive instructions to implement the ideas of these parameters from the patent literature relating to optimally useful frequencies. It was found that the specialist must choose which of the frequencies in the frequency range of several orders of magnitude (3×102-3×106MHz) should be selected when using microwaves.

In addition, as mentioned above, the disadvantage is that it is very expensive to create the installation, ensure the safety of personnel and machinery, if high or microwave frequencies are generated in a separate mouth of the stops (in most cases the immediate vicinity of the power line) and using waveguides are directed for use in a production setting. Along with a very inefficient use of valuable constructive space, it is necessary for these waveguides to install the expensive radiation detectors for the detection of possible damage in the security zone. All this makes it difficult for minimal maintenance (visually) and requires large expenditures for repair and easy. Already due to the failure of installation of pre-heating will result in loss of up to 30%, despite ongoing work, because the degree of compression without pre-heating is greatly increased and it is necessary to reduce by one third the speed of manufacture.

The objective of the present invention to provide a method and device that provide the possibility of achieving by means of a suitable frequency and high efficiency for heating the moldable material, and the heat must be evenly and energetically most ecologically and economically, before pressing this carpet moldable material in a continuously operating press. Simultaneously, the method and apparatus should enable the use of the structural elements with a small power consumption. Established in this regard, the device can be used to perform the method, but it should also work independently and must have a Le is to replaceable components and high resistance to interference.

The solution method is that heating of the Mat of compressible material used microwaves in the frequency range 2400-2500 MHz, while the microwave for each side of the extrusion are created in the 20-300 generators of microwaves from the magnetron power 3-50 kW each.

The solution for a device to implement this method, or for individual devices is that in continuous furnaces on one side of the pressing is 20-300 generators of microwaves from the magnetron power 3-50 kW, operating in the frequency range 2400-2500 MHz.

Using this method, and corresponding installation preferably heated carpets moldable material by weight, referred to the unit area, 2-40 kg/m2that move with the feed rate of from 50 to 2000 m/s At the height of the carpet after pre-compression in the manufacture of MDF (fiberboard medium density) is 40-350 mm, and in the manufacture of chipboard - 30-200 mm Oriented filler particle material (OSB) can be applied without pre-compression in the layer height 50-500 mm In one preferred embodiment, the framework for these data to be heated carpets moldable material is especially suitable magnetrons with power 6-20 kW. Used frequency lies in the ISM band (the range of the it industry, science and medicine), which is internationally recognized and does not require resolution frequency range for microwaves.

Experiments have shown that it is preferable if the length of the microwaves 12 cm large amount of microwaves absorbed in the carpet moldable material to the penetration depth of 200 mm These physical data can also be checked using the calculations; however, the penetration depth d is defined as the distance from the surface on which the wave power drops to 1/e=0,37, this corresponds to approximately 37% of the field strength E in the outer layers of material.

When the following existing boundary conditions

f=frequency=2.45 GHz,

C=speed of light≈3.108m/s,

ε'r≈3,5

ε r≈0,4, with tanδ=ε'r/ ε"r=0,11428

we obtain the formula

Thus, the corresponding penetration depth is d=0,183 m

Known to present high-frequency devices have the disadvantage that a large amount of radiation again out of the carpet moldable material, respectively, just passes through without heating of the Mat of compressible material. So after carpet moldable material on the other side you want to place the reflectors. It is costly for complex calculations better penetration, and is also appropriate for the management and regulation.

For microwave radiation using appropriate calculations and experiments, it was unexpectedly found that when the pre-compressed Mat of compressible material of MDF or similar material is achieved by the penetration depth of approximately 200 mm at a frequency of 2450 MHz. In the manufacture of chipboard OSB preliminary seal is not provided. Thus, when the height of the Mat of compressible material 400 mm, when irradiated from two sides with a penetration depth of 200 mm in the first passage about 60% of the energy is converted into heat energy, which provides optimum efficiency during heating.

At the same time with half-height and small carpets moldable material can be skipped with a significantly higher speed, since both sides are optimally absorb radiation and there is double the power.

A large number of generators, which is necessary for a device and method favorably leads to the small size of the holes of the radiation when the applied microwave frequency. The size of the holes is approximately 2×5 cm So you can arrange multiple generators in width and in a small structural space. Support hollow waveguides at the output preferably closed to protect from prob is the author of dust. When applying the ordinary to the present time of high-frequency radiation for heating carpets moldable material with a frequency of 930 MHz required a much larger hollow waveguides, so that it was impossible to install a large number of generators, respectively, of the waveguide width of the Mat of compressible material. The microwave generator is preferably in the form of modules, and it is possible to divide into separate parts for their repair or replacement. You can also entire microwave generator (including the magnetron, circulator and tuner etc) to perform in the form of a module and to provide quick locks for mounting and Dismounting. Thus, defective microwave generators can be quickly and easily removed from the device and replace with new ones. The replacement of individual parts used to present high-frequency installations accompanied by an extensive renovation that requires not only large staff costs, but also large lifting and mounting devices. Some of the cost of transporting the necessary materials or personnel to work in three shifts in place in case of an accident are high and require a lot of time. In contrast, replacement of the module is made of a microwave generator can be performed without problems and in a short time. Such fashion and due to their size can be easily stored, during operation of the plant is usually always a fixer.

In the installation, respectively, in the device may be located a metal detector for examination of carpets moldable material prior to microwave heating in the presence of metal parts. Especially critical are the metal parts with lengths greater than 1/4 wavelength (about 40 mm). In this case, due to the formation of sparks can ignite carpet moldable material. Because such effects may lead not only the magnetic part and you cannot remove them from the carpet moldable material using a conventional magnetic separators, before the heating Mat of compressible material should be able to reset it for deletion, or microwave generators are switched off when passing the identified metal parts, and the reset is not heated, thereby carpet moldable material can be accomplished then in front of the press. However, passing carpets moldable material must be checked for education sparks and fires. This is done using conventional sensors and measurement techniques. Simultaneously, the device preferably has means for extinguishing fires, or they are integrated into the production plant in place.

In one preferred the equipment example implementation of the device are the following technical framework conditions.

The overall efficiency of the furnace continuous action with the creation of microwaves consists of three different efficiencies. ηges1.η2.η3where η1corresponds to the efficiency of the transformer, which converts on the spot mains voltage into a DC voltage, η2corresponds to the coefficient used magnetrons in microwave generators, which convert the high voltage to the microwave radiation, and η3is the efficiency of converting microwave energy into thermal power in the carpet moldable material and corresponds to the temperature increase. When losses occur, for example, in the form of leakage radiation, reflected power, absorbed power, etc.

Usually η1and η2are defined by respective manufacturers and are in the preferred exemplary embodiment, the values η1=0.95 and η2=0,70. η3can be determined in laboratory experiments, and it depends in a high degree from the boundary conditions (for example, plastic tape) and subject to heating of the material. This material is filled with a mixture of fibers and/or chips that removal of air is pre-sealed and have relatively Bolshoy humidity.

In experiments under laboratory conditions, when the performance of 1 kg/s and the heating at 20 K was installed thermal capacity in article 36 kW, which corresponds to the coefficient η3=0,60. In another experience at the output of 0.5 kg/s was achieved by heating at 40 K while maintaining the same heating power, which confirms the efficiency. In terms of large plant with a capacity of 18 t/h and the width of the carpet after the circumcision party from 1850 to 21500 mm it turns out that 18 tons of source material in forming machines per hour must be heated with the help of the device at an average temperature of 30°C to 60°C. Thus, at the output of 5 kg/s and the desired heating T=30 To get heating power of the product of 270 kW. When the coefficient η3=0,60 get the total efficiency ηges=0,40 and the total input power of 675 kW. Thus, the required number of magnetrons and their capacity is further recalculation of 450 kW. When splitting on a selected number of magnetrons, for example, equal to 50, so, accordingly, the capacity of 9 kW on a single magnetron. In accordance with this, in the device is installed on each side surface of the pressing 25 magnetrons in microwave generators. Shows great, the tick, constructive enough space for this, so there is even the possibility of installing more order, for example, doubling the productivity and/or on-site installation of microwave generators, respectively, of magnetrons in reserve for alternately applying one set. Due to this, it is possible to prevent an unintended state of overheating in the installation and common problems with devices in a continuous 24/7 basis.

For professionals it is clear that for such a device must be provided with appropriate control mechanisms and control and remote maintenance. It is expedient to provide for the control loop, which is in accordance with capacity n kg/s negotiates power microwave generators and ensures optimal and energy-saving application. In this control loop should do is also evidence of moisture carpet moldable material, speed, etc. with a view to ensure appropriate regulation. In this case, the device may be provided by appropriate measurement technique.

In another preferred embodiment, have the following structure.

The molding strip is thicker than that used in continuous furnaces flax is a, suitable for microwave heating. The latter preferably made of Kevlar®. This is due to the need to develop a very wide carpet, which is then cut off on the sides by 10-20%, because the edges of the formed Mat of compressible material, usually have irregularities, such as, for example, the errors of laying or unintentional increase in density. For example, having a width of 2500 mm carpet moldable material is cut off on the sides before entering the pre-press to the width 2250 mm Thus, it is sufficient if used in the treatment zone microwaves tape in the passing continuous furnaces has a width of 2300 mm, It is preferable to fulfill the shielding boundary radiation from the microwave generator into the entrance of the furnace. Preferably on the longitudinal sides are provided stationary, and at the entrance and exit from the entrance of the furnace movable absorbing means, respectively, the elements that capture the regional and diffuse radiation. Special attention should be paid to preserve the moisture in the carpet moldable material, and to prevent the loss of moisture during heating due to the evaporation of moisture may be necessary to provide also lying on the carpet of compressible material endlessly circulating plastic tape. Load the of using microwaves is preferably causes a uniform temperature distribution within +/-7°C in the carpet 14 moldable material along the length and width.

Other preferred measures embodiments of the subject invention follow from the dependent claims and the following description with reference to the accompanying drawings, which schematically:

figure 1 - installation for the manufacture of slabs of material from the laying of the carpet moldable material for forming the tape to the beginning continuously working dvuhnitochnogo press, side view;

figure 2 is a device for preheating of the Mat of compressible material using microwaves of figure 1, on an enlarged scale; and

figure 3 is a device for preheating of the Mat of compressible material with the layout of microwave generators, top view.

1 schematically shows a side view of a production plant for the manufacture of slabs of carpet 14 moldable material. It consists mainly of one or more sections 16 of laying, which continuously plank carpet 14 moldable material in one or more layers for forming the tape 6. In the direction 3 is a prior press 17 consisting of endlessly circulating over molding tape 6 anti-squeak tape 19. To maintain the molding tape 6 at high pressure down below it may be located endlessly circulating the ribbon 18. In the example shown is carried out is shown continuously operating press 1, which is made as dvuhnitochnogo press circulating steel belts 7 and heated clamping plates 2. Circulating steel tape 7 is guided relative to the heating clamping plates 2 through 5 tel rolling, for example parallel to each other and making a forced movement of the rolling rods.

Continuous furnace 4 continuous action right in front of incoming steel bands 5 continuously operating press 1. Thus the carpet 14 moldable material to pass through the checkpoint furnace 4 is transferred from the molding tape 6 on the bottom of the plastic tape 11 and, if necessary, depending on the type and execution pass of the furnace 4 is clamped circulating from the top with plastic tape 8. Located on both sides of the microwave generator 26 absorbent stones 25 is located with the capability of raising and lowering by means of device 12 height adjustment and are set depending on the height of the passing of carpets moldable material. The device height adjustment for circulating the top of the plastic film 8 is not shown. The top plastic strip 8 has the task of protecting the entrance of the furnace 4 from increased dust through the carpet 14 moldable material and prevent the spring return of the carpet 14 moldable material in primetransport back to their original state prior to sealing with pre-press 17. Top plastic tape 8 can also prevent the escape of moisture during preheating.

Depending on the overall design of the production installation, you can perform molding tape 6 in the form suitable for use in the treatment zone microwave molding tape 6 and conveying the carpet 14 moldable material through the checkpoint oven 4 without transferring to another tape. Suitable for microwaves molding or plastic tape 6, 8, 11 characterized by the fact that they are passing through the area of microwave generators 26 are heated only by about 10°C. suited For this, for example, a strip of Kevlar® with Teflon coating on one or both sides.

As shown in figure 2, a simple device passing the furnace 4 is performed as follows. On the lower frame 23 circulates the bottom of the plastic tape 11 with the actuator 11. When this molding strip 6 passes carpet 14 moldable material on the bottom of the plastic tape 11. The gap between the two circulating endless belts covered by carpet 14 moldable material, otherwise provide funds, which provide passage without damage to the carpet 14 moldable material on the bottom of the plastic tape 11 pass of the furnace 4. On the upper frame 24 is the device 12 regulirovanie the height provided at the inlet 27 and outlet 28 passing furnace 4 absorbing elements 25 for correct shielding of the generated microwave generators 26 microwave radiation and provide preliminary heating carpets 14 moldable material of varying heights. Similarly, you can adjust the width of the inlet 27 and outlet 28. This regulation width and height for the upper circulating plastic tapes 8 are not shown. Absorbing elements 25 can be performed, for example, in the form of absorbent stones or vessels with water. However, along with absorbing elements 25 may also be provided by the reflectors (for example, perforated metal sheets or other suitable means), or a combination of these two possibilities. The reflectors are preferably arranged so that they direct the scattered radiation again directly into the carpet 14 moldable material. In addition, can be provided by the sensor 29, which measure the thickness and width of the carpet 14 moldable material and accordingly set the inlet 27 and outlet 28 for carpet 14 moldable material.

On the holding frame 15 in the middle of the entrance of the furnace 4 are microwave generators 26. Microwave generator 26 comprises at least one magnetron 20, agreed circulator 21 and tuner 22. The tuner 22 performs a fine adjustment of microwave radiation, respectively, its orientation, while the circulator 21 receives the reflected microwaves and supplies for future use. In basinstoke heated primarily water from the water-cooling 9 to absorb the excess microwave radiation. Position 13 marked the metal detector device. It can also be located depending on the installation directly above the molding strip 6 before passing the furnace 4. In this case, it is preferable to consider the possibility of dropping or removal with the metal parts of the Mat of compressible material before passing the furnace 4. As an alternative solution, or when the detector 13 of metal is located within the path of circulation of the plastic tapes 8, 11 before absorbing elements, the microwave generator 26 during the passage of a piece of metal for a short time off and part of the carpet 14 moldable material which is not heated, is discharged through near press 1 fixture.

Figure 3 on the top view shows the many necessary microwave generator 26 to the width of the carpet 14 moldable material, which is transported in the direction 3 of the continuously operating press 1. Expert it is clear that the introduction of microwave radiation should be carried out from the side of the compression surfaces, which then come into contact with a steel tape 7 press 1. The input of microwave radiation through a narrow, respectively, the longitudinal surface of the edge of the carpet to take inappropriate material on the basis of theoretically and practically ODA is divided by the depth of penetration.

Regarding facilities maintenance installation it is preferable to provide in the entrance of the furnace 4 modular implementation of some parts of the microwave generator 26, such as a magnetron 20, the circulator 21, a tuner 22, and to provide for easy replacement in case of a defect or repair.

In the alternative or additionally preferably, if the entrance of the furnace 4 each microwave generator 26 is made as a separate module and has, if necessary, high-speed connections for disassembly and Assembly. To enhance the operational safety of the entrance of the furnace 4, or it may be provided with sensors to detect sparks and/or fires in the carpet 14 moldable material and/or and/or means to extinguish the fire.

The list of items

1Continuously operating press
2Clamping the heating plate in the press 1
3Operating direction
4Continuous belt furnace continuous action
5The rolling body
6 Molding tape
7Steel tapes
8Top plastic tape
9Water cooling
10The drive for the tape 11
11The bottom plastic tape
12The device height adjustment
13Metal detector
14Carpet moldable material
15Retaining frame for generators 26
16The plot of laying
17Pre-press
18The lower guide rolls
19The presser belt
20The magnetron
21The circulator
22the UNEP
23Bottom frame
24Top frame
25Absorbing elements
26Microwave generators
27Input
28Output
29Sensors

1. Method preheat covered with endless continuously circulating molding tape (6) of the Mat (14) of the compression of the material during the manufacture of chipboard, and for preheating of the Mat (14) of the compression material on one or both sides of the compression surfaces of the Mat (14) moldable material is injected microwave radiation, and the Mat (14) of the compression of the material after the transfer of the continuously operating press (1) press and subjected to curing by application of pressure and heat, wherein the heating Mat (14) of compressible material using microwaves in the frequency range 2400-2500 MHz and microwave for each side of the pressing create 20-300 microwave generators (26) with magnetrons (20) 3-50 power kW each.

2. the procedure according to claim 1, characterized in that the heating using microwaves causes uniform distribution of temperature within +/-7°C in the Mat (14) of the compression of the material along the length and width.

3. The method according to claim 1, characterized in that the Mat (14) of the compression of the material prior to heating check for the presence of metal parts, while looking for first of all the metal parts with lengths greater than 1/4 wavelength is about 40 mm

4. The method according to any one of claims 1 to 3, characterized in that the inlet (27) and/or output (28) passing the furnace (4) continuous action automatically agree on the height and width of the Mat (14) of the compression of the material.

5. The method according to claim 1, characterized in that the molding tape (6) suitable for microwaves and holds the Mat (14) of compressible material directly through the checkpoint furnace (4).

6. The method according to claim 1, characterized in that is used in the entrance of the furnace (4) plastic tape (6, 8, 11) is heated in a single pass less than 10°C.

7. The method according to claim 1, characterized in that to prevent the escape of moisture from the carpet (14) of the compression of the material in the entrance of the furnace (4) use of upper endlessly circulating plastic tape (8).

8. The method according to claim 1, characterized in that during the passage of the Mat (14) of the compression of the material absorbing elements (25) in the entrance of the furnace (4) is moved as close as possible to the Mat (14) of the compression is of material.

9. The method according to claim 1, characterized in that as absorbing elements (25) use absorbent stones, or water containers, or other suitable means.

10. The method according to claim 1, characterized in that the reflectors impose excessive scattered radiation back into the Mat (14) of the compression of the material.

11. The method according to claim 3, characterized in that the microwave generators (26) in the areas of the entrance of the furnace (4), which is not transported to the Mat (14) of compressible material and/or are experiencing a metallic foreign body, automatically switch off.

12. The method according to claim 1, characterized in that the required cooling capacity by means of reverse thermal communication transform for Central heating or similar purposes.

13. The method according to claim 1, characterized in that during the passage of the Mat (14) of the compression of the material through the checkpoint furnace (4) it checks for the presence of sparks and fire.

14. The method according to item 13, characterized in that the resulting sparks and/or fires automatically stew.

15. Device for preheating is covered with an endless continuously circulating molding tape (6) of the Mat (14) of the compression of the material during the manufacture of chipboard, and the device is made in the form of the entrance of the furnace (4) continuous operation, in which a pre-heating of the Mat (14) press the been created material are microwave generators (26) for generating microwaves, aimed at one or both sides of the rug surface (14) of compressible material, characterized in that the entrance of the furnace (4) continuous for each side of the compression surfaces is 20-300 microwave generators (26) with magnetrons (20) 3-50 power kW and a frequency range 2400-2500 MHz.

16. The device according to item 15, characterized in that opposite to the working direction (3) is the separator (13) metal.

17. The device according to item 15 or 16, characterized in that the entrance of the furnace (4) or in front of it are the sensors (29) to define the width and/or height of the Mat (14) of the compression of the material.

18. The device according to item 15, characterized in that the inlet (27) and/or output (28) passing the furnace (4) is made with the possibility of changing the height and/or width.

19. The device according to item 15, wherein to modify the input (27), respectively, yields (28) is provided movable absorbing elements (25).

20. The device according to item 15, wherein as the shock-absorbing elements (25) are provided absorbent stones and/or water containers.

21. The device according to item 15, characterized in that in addition or instead of absorbing elements (25) in the entrance of the furnace (4) are reflectors in the form of perforated metal sheets, or other suitable means.

22. The device according to item 15, wherein the entrance of the furnace 4) separate parts, such as a magnetron (20), a circulator (21) and the tuner (22) of the microwave generator (26) are designed as separate modules, suitable for quick replacement.

23. The device according to item 15, wherein the entrance of the furnace (4) each microwave generator (26) is designed as a module and, if necessary, equipped with high-speed connections for mounting and Dismounting.

24. The device according to item 15, wherein the entrance of the furnace (4) or there are sensors to detect sparks and/or fires in the Mat (14) of the compression of the material or on it.

25. The device according to item 15, wherein the entrance of the furnace (4) or provided with means for extinguishing a fire.



 

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15 cl, 23 dwg

FIELD: electricity.

SUBSTANCE: high-frequency heating device comprises inverter to rectify AC energy and to transform AC energy into high-frequency energy, step-up transformer to increase voltage of high-frequency energy extracted from inverter, high-voltage circuit for transformation of output signal of transformer into high DC voltage, magnetron for reception of high DC voltage and radiation of microwave, the first current-sensitive resistor provided in the first circuit, where anode current of specified magnetron flows, the second current-sensitive resistor separated from specified first current-sensitive resistor, controller to control oscillations of magnetron. Controller checks condition of earthing for the first wiring board and specified second wiring board.

EFFECT: invention achieves more reliable prevention of electric shock to user.

8 cl, 9 dwg

FIELD: protection of materials, in particular, wood, objects of architectural and cultural value by processing these with microwave energy, or objects, infected with pests or containing harmful substances, as a result of which their sanitation is achieved.

SUBSTANCE: in accordance to inventions, two magnetrons G1, G2 or antennas only are mounted on object being irradiated O, directly in front of each other. Method of temporary alternation of generators control is available in device. By means of signals from thermo-measuring probes, processed by computer, and by means of signals formatting block, control device and generators G1, G2, operation mode of generators G1, G2 is precisely set to precise temperature required for object O, including temperature mode. Usage of microwaves for processing objects and items, infected with pests and/or containing harmful substances, allows achievement of controlled increase of temperature and therefore of destruction of harmful organisms and decontamination of these objects.

EFFECT: creation of device and method, providing microwave processing of wood and other materials including those in hard to access or inaccessible locations for destroying harmful organisms, located in aforementioned objects, such as insects and fungi, or for removal of harmful substances from these objects (decontamination), while achievement of even temperature profile is ensured across volume of object, and reliable destruction or reliable decontamination.

3 cl, 4 dwg

FIELD: microwave ovens.

SUBSTANCE: proposed microwave oven has housing that dictates its appearance; cooking chamber formed inside housing; microwave radiation generating unit that generates microwaves radiated into cooking chamber; plurality of ventilation ports formed in side wall of cooking chamber for ventilating the latter; water accumulation cavity formed at cooking chamber bottom and designed to hold vapor-producing waster; and ventilation window control unit which selectively closes ventilation ports. In the course of cleaning microwave oven with vapor ventilation ports are closed to prevent vapor leakage from cooking chamber and from microwave oven into surrounding atmosphere.

EFFECT: facilitated cleaning of cooking chamber inner surfaces.

27 cl, 10 dwg

The invention relates to a device and method for storing and managing data of recipes for microwave circuit

The invention relates to power supplies for microwave ovens and used them in the fuse high voltage

FIELD: process engineering.

SUBSTANCE: invention relates to jointing the ends of wood sheet materials, particularly, to making mate grooves at said ends. Proposed method comprises, at least, driving the groove at end of said sheet material by rotary cutting tool. Note here that warped section of said end is leveled by clamping plate. This allows avoiding deep cutting and ensures equal size and shape grooves.

EFFECT: higher strength and reliability of joint.

4 cl, 25 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to production of wood-filled composite materials based on timber wastes and mineral binders. Proposed method comprises mixing wood filler with binder. Filler is treated in tight chamber in atmosphere of flue gases at 190-200°C for 50-60 minutes. Then, prior to mixing, filler is processed in plasma-forming gas flow in discharge chamber at high-frequency generator power of 200-600 W and vacuum of 100-130 Pa for 250-280 s. Air is used as said plasma-forming gas fed at flow rate of 0.08-0.12 g/s. After mixing of filler and binder, molding and heat treatment are performed.

EFFECT: higher strength.

1 tbl, 2 ex

FIELD: wood working industry.

SUBSTANCE: invention relates to wood working industry and may be used in production of multilayer particle boards. A line to manufacture particle boards comprises a belt conveyor, a machine to generate a chip carpet, a press and a spraying plant installed upstream the press with a valve to supply water. At the same time the line is equipped with an additional spraying plant with a valve installed upstream a shaping machine and a unit to measure warpage of boards installed downstream the press. Outlets of the unit to measure warpage are connected to control inlets of spraying plant valves. Due to development of moisture asymmetry of surfaces in the initial chip carpet, as a result of which mechanical stress occurs in a formed board during pressing that compensate for its warpage, which starts immediately after unloading of a board from the press, warpage in finished boards is eliminated.

EFFECT: invention may be used in production of multilayer wooden boards.

2 dwg

FIELD: process engineering.

SUBSTANCE: invention relates to recovery of solid household wastes into polymer-wood composite material to be used in production of components and parts of machines, equipment and construction structures. Proposed method comprises wastes mincing, mixing, thermal extrusion and activation. Activation is performed by magnetic-acoustic resonance effects in the frequency range of 5 to 15 kHz and radiation power of 15 to 20 mW.

EFFECT: higher efficiency and rate, improved mechanical properties.

4 cl, 2 tbl, 1 ex

Cooler for trays // 2335392

FIELD: heating.

SUBSTANCE: unit includes housing (1), conveyor (2) for tray (3) delivery, covering chambers (4, 5) of air and water cooling. In addition, air or water cooled chambers (4, 5) are provided with walls (6), installed inside chambers (4, 5) along conveyor. Air cooled chamber (4) walls (6) are perforated, while water-cooled chambers (5) are made of capillary porous material with steam discharge pipes (9).

EFFECT: improvement of output and reliability.

2 cl, 1 dwg

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