Cooling of induction motor rotor

FIELD: engines and pumps.

SUBSTANCE: invention relates to a squirrel-cage rotor for an induction machine and to a method of its fabrication. The squirrel-cage rotor comprises a rotor core 1 of sheets, short-circuited rods 2 arranged inside the said core 1 and short-circuited rings 3 abutting on the said core 1 to electrically interconnect the said rods 2 at the rotor core end sides. For better heat removal, heat pipes 4 are fitted axially in the said rotor core 1 to extend therefore at end sides and to fit in the short-circuited rings 3.

EFFECT: better heat removal from the squirrel-cage rotor of the induction motor.

14 cl, 8 dwg

 

The invention relates to a squirrel-cage rotor for an asynchronous machine, which has a sheet package of the rotor with primetime on the front side to the sheet package rotor short rings. In particular, the invention relates to the cooling of such a squirrel-cage rotor.

In addition, the invention relates to a method of manufacturing such a squirrel-cage rotor, which provides adequate cooling.

To increase the efficiency of electric machines use different technologies for cooling, by means of which occur in the stator and rotor heat is dissipated to the environment. Heating of the rotor is considerably more heating of the stator. However, it is more difficult to dissipate heat from the rotating structural element, which is the rotor.

From DE 4308683 A1 famous squirrel-cage rotor for an asynchronous machine, which is in the grooves of the sheet bundle squirrel cage rods on both end sides are connected mechanically and electrically manufactured through injection molding of aluminum short rings.

The usual method of heat removal from such rotors is running short rings with blades for the purpose of heat dissipation in the inner space of the engine. The effectiveness of this cooling method C is dependent on the rotation speed of the engine. In machines with a large number of poles efficiency of heat removal using the blades on short ring less. In addition, the efficiency of such a cooling method decreases with the axial length of the sheet pack of the rotor, as in this case, it becomes more and more difficult to provide the opportunity for sufficient heat dissipation from the entire sheet package of the rotor.

The basis of the invention is to improve heat dissipation from the squirrel-cage rotor asynchronous machine.

This problem is solved by using a squirrel-cage rotor with signs of paragraph 1 of the claims. Such a squirrel-cage rotor for an induction motor includes:

- sheet package of the rotor

- located inside the sheet package squirrel cage rods and

- prelite to the sheet package rotor short rings, which connect electrically with each other squirrel-cage terminals on the front side of the sheet package rotor

when this sheet in the package sealed rotor in the axial direction of the heat pipe, which on the front side protrude from the sheet pack of the rotor and are short rings.

In addition, the problem is solved using the method of manufacturing a squirrel-cage rotor for an asynchronous machine with signs of paragraph 12 of the claims. In this way, the heat pipes contribution is live in grooves sheet package of the rotor and poured short ring to the end sides of the sheet pack of the rotor and to the heat pipes that they connect electrically with each other squirrel-cage terminals short-circuited rotor and that heat pipes are on the front side of the sheet package of the rotor and are short rings.

Preferred embodiments of the invention follow from the dependent claims.

The basis of the invention lies in the understanding that in the squirrel-cage rotor with primetime on the front side short rings these short rings can very well be used for heat dissipation through their tide directly to the ends of the heat pipes. Heat pipes, which can be thermosyphons or heat pipes penetrate the sheet package of the rotor essentially in the axial direction. They transport heat, which occurs in the sheet package of the rotor, to both gable ends of the rotor. To these ends they merge in the short ring, which is almost optimal heat transfer from the heat pipes in short rings. Having a large surface area short rings function as a condenser for the heat pipes, so a very simple way, the efficient circulation of heat.

In a preferred embodiment of the invention, the heat dissipation sheet package of the rotor is also usilivaetsya, that heat pipes on the opposite sheet of the package of the rotor-side play in the axial direction of the short rings. Speaking of short rings of the heat pipe runs through the function of the fan blades and supported thereby convection.

In another preferred embodiment, a short ring is made of aluminum, and a heat pipe made of copper, with heat pipes in areas where they are located within a short rings, formed doped layer, which is caused, in particular, galvanically. Short rings from aluminum has the advantage that due to this, you can significantly reduce the moment of inertia of the rotor in comparison with more severe short rings of copper. In addition, aluminum is very well suited for molding method on the basis of its relatively low melting point. The use of heat pipes made of copper has the advantage that a particularly effective thermal conductivity, since copper has a very high coefficient of thermal conductivity. To optimize heat transfer between the heat pipes and short rings in one embodiment, the heat pipe caused doped layer of mixed crystals. Such a coating can be applied galvanically In the alternative it is also possible galvanizing heat pipes in order to achieve the desired reduction of thermal resistance. Using doped layer improves both thermal and the mechanical connection of heat pipes with short rings. Effectively prevents separation of the heat pipes from short rings due to cycles of thermal load during the operation of the asynchronous machine. Reduced electrical contact resistance between the heat pipes and short rings. It is preferable, in particular, when the heat pipes are not only used for heat dissipation, but also as a short circuit of the terminals in the asynchronous machine.

One preferred embodiment of the invention is characterized by the fact that the sheet pack of the rotor has a first groove, which are short-circuited terminals, and the second grooves, which are heat pipes. The second groove may be preferably made in the form of axial holes. Them slide heat pipes before the tide short rings.

In particular, when the heat pipe has a higher electrical resistance between short rings than the short-circuit terminal, the preferred embodiment of the invention, in which the second groove is located further outside relative to the first grooves, when viewed in the radial direction of the short is zamknutogo rotor. In this case, the heat pipes can be used as a starting rod on the basis of their higher electrical resistance. The actuator rods should be located on the basis of the skin effect on the outside when viewed in the radial direction than the operating rods for their purpose. The higher electrical resistance of the starting rod provides increased starting torque of the machine.

In contrast, if the heat pipe has a lower electrical resistance between the short rings than the short-circuit terminal, it is preferred embodiment of the invention, in which a first groove is located on the first grooves on the outside when viewed in the radial direction of the squirrel-cage rotor. This applies to the case when the heat pipe is made of copper, and short rods of aluminum. For example, it is possible that in the process of pressure die casting aluminum the first groove is filled with the aluminum melt simultaneously with the tide short rings. Due to this, in a single stage to perform a short-circuited terminals and short rings. Such a squirrel-cage rotor is very economical to manufacture.

In contrast, workers rods form the heat pipes made of copper, electrical resistance which is relatively small.

Regardless of whether heat pipes as working rods or starting rods, they can be preferably also inclined. In particular, it is advisable to perform a short-circuited terminals is also inclined. Such a squirrel-cage rotor includes sloping the starting rod and the operating rod, with one type of these rods is formed depending on the option run by heat pipes. The tilt-rotor impact positively on the starting characteristics of asynchronous machines. Pulsating moments, which are called the upper harmonics in the field of the air gap, are compensated by tilt.

Another preferred embodiment of the invention is characterized by the fact that each first groove is connected with a corresponding second groove through the connecting jumper with formation of a double rod grooves. For example, when applying the method of pressure die casting aluminum for the manufacture of short rings and cage rods first invest in the second groove of the heat pipe. Then equipped with heat pipes sheet package of the rotor is injected into the mold for injection molding. It serves under the pressure of the aluminum melt, and the melt penetrates into the first SC is where it is refuelled and connective jumper and fills these areas. Simultaneously poured short rings on the speakers on the front side of the sheet package of the rotor heat pipes.

In another particularly preferred embodiment, a particularly high electrical efficiency is achieved in a hybrid design that short circuit the terminals are made of copper, and the first grooves are moulded studs that fill the residual cross-section which is not filled with squirrel-cage terminals in the first grooves, with alloy cores and short rings are made from aluminum. Short rods of copper significantly increase the conductivity and thus the efficiency squirrel cage rotor. Using aluminum melt, which fills the residual cross-section, short rods well mechanically fixed within the grooves.

Since heat pipes are located in a rotating element, a short-circuited rotor, they do not necessarily have to have a capillary insert, which is used in heat pipes. The capillary is not required because the asynchronous machine heat pipe of centrifugal force, through which liquid contained in them one's pressing away on the outside. Therefore, in a preferred embodiment of izopet is of the circulation of heat can be realized by performing heat pipes that is encased in a heat pipe medium with a rotating squirrel-cage rotor can circulate under the action of centrifugal forces. In the sheet package of the rotor, which is the most hot spot on the heat pipe evaporates the liquid film in the direction of the outward due to centrifugal force. Vapor that arises in this case, one's pressing away coming into the circuit by the liquid inside and moves at high speed in the axial direction to the short ring, which performs the function of the capacitor. Here is ultimately the translation pair in the liquid state. The medium in the liquid state in the end, again adjacent the outside to heat the tube due to centrifugal forces.

In combination squirrel-cage rotor according to one of the above embodiments, the stator is obtained asynchronous machine, the efficiency of which is based on the cooling efficiency is significantly improved compared to conventional asynchronous machine with squirrel-cage rotor.

Below is a more detailed description and explanation of the invention on the basis of examples with reference to the accompanying drawings, which depict:

Fig.1 is a longitudinal section of a first variant of the run sheet package of the rotor with heat pipes;

Fig.2 - cross the incision of the first variant;

Fig.3 is a longitudinal section of a second variant of the run sheet package of the rotor with heat pipes;

Fig.4 is a cross section of a second variant implementation;

Fig.5 is a third embodiment of a sheet package of the rotor with heat pipes;

Fig.6 is a fourth embodiment of a sheet package of the rotor with heat pipes;

Fig.7 - the principle of the heat pipe;

Fig.8 is an asynchronous machine with sheet package of the rotor according to a variant implementation of the invention.

In Fig.1 shows in longitudinal section a first embodiment of a sheet package 1 rotor with heat pipes 4. Sheet package 1 of the rotor is made from stacked in the axial direction, electrically isolated from each other, the electrical steel sheets. This reduces the losses in the steel and losses by eddy currents in the sheet package 1 of the rotor.

In addition, the sheet package 1 rotor includes first grooves, which are short-circuited terminals 2. To achieve the highest possible electrical efficiency of these squirrel-cage terminals 2 are made of copper.

In addition, the sheet package 1 of the rotor comprises a second groove in the form of an axial bore in which is located a heat pipe 4. When viewed in the radial direction of the sheet package 1 rotor heat pipes 4 and the eat also the second grooves are located on inside, than squirrel-cage terminals 2, respectively, the first groove.

In the manufacture shown here squirrel-cage rotor at first enter a squirrel-cage terminals 2 and the heat pipe 4 into the corresponding grooves. Then fitted them sheet package of the rotor is placed in a mold for injection molding. It to the sheet package 1 of the rotor on the end sides poured short ring 3. Short ring 3 surrounds the end of the short-circuited ends of the rods 2 and the heat pipes 4. Thus, in the area of these ends there is a very good mechanical, electrical and thermal contact between short-circuited terminals 2 and short rings 3, and between the heat pipes 4 and short rings 3.

To make the connection between these elements even more durable as squirrel-cage terminals 2 and the heat pipe 4 before the introduction of sheet in the package 1 of the rotor is provided with a coating. Thus the heat pipe 4 and the short-circuit terminals 2 is applied aluminum layer. This aluminum layer should be applied at least in the zone in which the short-circuit terminals 2, respectively, of the heat pipe 4 after the process of injection molding are in short ring 3. In particular, due to the galvanization of these elements occurs doped layer between the Corot is cotacotani terminals 2 and short rings 3, and between the heat pipes 4 and short rings 3. Formed mixed-crystal area, which provides especially strong mechanical connection. This mixed-crystal compound withstands the loading cycles, which cause distortions within the rotor.

Transient conductivity between short-circuited terminals 2 and the short ring 3 remains very small after many load cycles. Transition the conductivity between made in this case as an example of the copper heat pipes 4 and the short ring 3 remains extremely high, so that the heat made from, for example, in the form of thermosyphon heat pipes 4 may very well be allocated in the short ring 3. Short ring 3 are for thermosyphon having a large surface area condenser.

In Fig.2 shows a first embodiment of a cross section. An incision is made through one of the short rings. The number of first grooves, which are short-circuited terminals 2, significantly more than the number of the second grooves, which are provided for heat pipes 4. Naturally, their ratio can optionally be changed. If you want to take away from the rotor a greater amount of heat, the design envisages the more what shows four heat pipes 4. It is also possible and meets the invention is the use of heat pipes 4 as short rods for squirrel-cage rotor.

In Fig.3 shows a longitudinal section of a second embodiment of a sheet package 1 rotor with heat pipes 4. Similarly shown in Fig.1 option run here also provides the first grooves to accommodate the short-circuited terminals 2 and second grooves, which are made in the form of axial holes for placement of the heat pipes 4. In this embodiment, the second grooves, and thus the heat pipe 4 when viewed in the radial direction is located outside, i.e., near the outer casing. Squirrel-cage terminals 2, which in this case is made of copper, are, when viewed in the radial direction of the rotor inside, i.e., closer to the rotor shaft. In this embodiment, the heat pipes 4, which are also made of copper, are used as the starting rods for squirrel-cage rotor. Their cross-sectional area significantly smaller than the short circuit of the terminals 2. Thus, electrical resistance, which form a heat pipe between the two short rings, much greater than the resistance of the short circuit of the terminals 2.

On the basis of skin-the effect is that the currents in the rotor during the starting torque become to the outer circumference of the rotor, i.e. in the direction of the second grooves. Thus, they are in worse conductive heat pipes 4. This leads to the fact that improved starting characteristics of asynchronous machines. When approaching to the nominal rotor speed the flow of current more and more closed through much better conductive squirrel-cage terminals 2. This reduces the losses in the rotor and improves electrical efficiency. In this implementation there is no need to provide the starting rod, as it is often implemented in squirrel-cage rotor according to the prior art, to improve the starting characteristics. Function trigger rods are preferably performed simultaneously performed, for example, in the form of thermosyphons heat pipes 4.

In Fig.4 shows a second embodiment of a cross section. You can see that for each short rod 2 includes a heat pipe 4. Thus, each operating rod, which is formed by using short rods 2, corresponds to the actuator rod in the form of a thermosyphon.

In Fig.5 shows a third embodiment of a sheet package of the rotor with heat pipes 4. Here, as the heat pipes 4, and the short-circuit terminals 2 are located in the so-called dual core grooves. That is, when the volume of the first groove, which are provided for the short-circuited terminal 2, connected through a thin connecting the jumper with the second groove, which is provided for the heat pipe 4. The drawing shows a section through a sheet package of the rotor and thereby through the short-circuited terminals 2 and the heat pipe 4. Heat pipes 4 when viewed in the radial direction are located further inside than the short-circuit terminals 2. This arrangement has, in particular, sense when the electrical resistance which creates heat pipe 4 between the two short rings, less electrical resistance, which form a squirrel-cage bars 2 between the two short rings.

Typically, the surface of the cross-section of the heat pipe 4 is less than the massively made short rods 2. However, if you are short rods of aluminum, for example from die-cast aluminum melt, and heat pipes 4 are composed of copper, such a location can be quite suitable, because with this choice of materials the electrical resistance of heat pipes may be less than the short-circuited terminals. In this implementation to improve starting characteristics should be positioned in heat pipes 4 when viewed in the radial direction BC is the same inside, i.e. near the rotor shaft. When this squirrel-cage terminals 2 aluminium function of the starting rod.

In Fig.6 shows a fourth embodiment of a sheet package of the rotor with heat pipes 4. Here, as in Fig.5, has a dual core grooves to accommodate the short-circuited terminals 2 and heat pipes 4. However, here the short-circuit terminals 2 are, when viewed in the radial direction inside, and the heat pipes 4, when viewed in the radial direction from the outside. This location makes sense when you short circuit the terminals 2 have better electrical conductivity between the two short rings than heat pipes 4. This occurs in particular when the short-circuit terminals 2 and the heat pipe 4 is made of the same material, for example, copper or aluminum. In this case, the heat pipes 4 are used as the starting rods and short rods 2 as working rods.

In Fig.7 shows the principle of the heat pipe 4 in a rotating squirrel-cage rotor. Shows a section through the heat pipe 4, sheet package 1 of the rotor and shorting sleeve 3, which prelit from the front side to the sheet package 1 of the rotor. The heat pipe 4 is on the opposite sheet of the package 1 of the rotor side of the short colza. This protruding portion of the heat pipe 4 serves as a vent blades and thereby further improves air circulation.

Inside the heat pipe 4, which is made in the form of a thermosyphon, the environment is located in a partially liquid and partially gaseous state. Fluid 5 at the expense caused by the rotation of the squirrel cage rotor of the centrifugal force of one's pressing away in the direction of the circumference of a squirrel-cage rotor. Accordingly, when viewed in the radial direction, pairs of 6's on the inside. In the package of the rotor, as at the hottest point of thermosyphon, evaporates directed outward the liquid film. Pair 6 one's pressing away coming into the circuit by the liquid 5 to the inside and moves at high speed in the axial direction to the short ring 3, which acts as a condenser. There is again turning pair 6 in the liquid. The medium in the liquid state in the end, again adjacent to the outside of thermosyphon due to centrifugal forces.

In Fig.8 shows an asynchronous machine 7 sheet package of the rotor according to one embodiment of the invention. Asynchronous machine 7 is characterized in this case, a particularly high electrical efficiency. In contrast to the above options execution is applied, the rotor is fabricated is of copper by way of injection molding. In the manufacture method of injection molding of the rotor of the copper sheet package of the first rotor supply, as discussed above in relation to other options run heat pipes. These heat pipes are placed in the corresponding grooves of the sheet pack of the rotor. Then equipped with heat pipes sheet package of the rotor is injected into the mold for injection molding. In this form for molding serves a copper melt, which forms on the front side short rings and other fills grooves sheet package of the rotor. After solidification of the melt in the other grooves occur cage rods of copper.

1. Squirrel-cage rotor for an asynchronous machine (7), with squirrel-cage rotor includes:
- sheet package (1) rotor
- located inside the sheet package (1) of the rotor squirrel-cage terminals (2) and
- prelite flat package (1) rotor short ring (3), which connect electrically with each other squirrel-cage terminals (2) on the front side of the sheet package (1) rotor
when this sheet in the package (1) rotor clamped in the axial direction of the heat pipe (4) that on the end sides protrude from the sheet package (1) of the rotor and are short ring (3), with short ring (3) made of aluminum, and Joe is e pipe (4) - copper and heat pipes (4) in areas where they are located within a short rings (3), formed doped layer, which is caused, in particular, galvanically.

2. Squirrel-cage rotor under item 1, in which the heat pipe (4) on the opposite sheet of the package (1) rotor-side play in the axial direction of the short rings (3).

3. Squirrel-cage rotor under item 1, in which the sheet package (1) of the rotor has a first groove, which are short-circuited terminals (2), and the second grooves, which are heat pipes (4).

4. Squirrel-cage rotor according to p. 3, wherein the second grooves are located further outside relative to the first grooves, when viewed in the radial direction of the squirrel-cage rotor, and a heat pipe (4) has a higher electrical resistance between short rings than the short rod (2).

5. Squirrel-cage rotor according to p. 3, in which the first groove is located on the first grooves on the outside when viewed in the radial direction of the squirrel-cage rotor, and a heat pipe (4) has a lower electrical resistance between the short rings than the short rod (2).

6. Squirrel-cage rotor according to p. 3, in which each first groove soy is inane with a corresponding second groove through the connecting jumper with formation of a double rod grooves.

7. Squirrel-cage rotor under item 1, in which heat pipes (4) are performed so that is enclosed in a heat pipe (4) environment with a rotating squirrel-cage rotor can circulate under the action of centrifugal forces.

8. Squirrel-cage rotor according to any one of paragraphs.1-7, in which the short-circuit rods (2) from cast aluminium.

9. Squirrel-cage rotor according to any one of paragraphs.3-7, in which the short-circuit rods (2) are made of copper and the first grooves are moulded studs that fill the residual cross-section which is not filled with squirrel-cage terminals (2) in the first grooves, with alloy cores and short ring (3) made of aluminium.

10. Asynchronous machine (7) containing a stator and a squirrel-cage rotor according to any one of paragraphs.1-9.

11. A method of manufacturing a squirrel-cage rotor for an asynchronous machine (7), in which the heat pipe (4) into the grooves of the sheet package (1) rotor and poured short ring (3) to the end sides of the sheet package (1) of the rotor and to the heat pipe (4) so that they connect electrically with each other squirrel-cage terminals (2) squirrel-cage rotor, which are located inside the sheet package (1) of the rotor, and that the heat pipes (4) are on the front side of the sheet package (1) of the rotor and are short ring (3), if et is m short ring (3) cast aluminum, and heat pipes (4) are composed of copper, and heat pipes (4) in areas where they are located within a short rings (3), form a doped layer which is applied, in particular, galvanically.

12. The method according to p. 11, in which the heat pipe (4) into sheet package (1) of the rotor so that they are on the opposite sheet of the package (1) rotor-side play in the axial direction of the short rings (3).

13. The method according to any of paragraphs.11-12, in which the short-circuit rods (2) cast from aluminum by a process of injection molding.

14. The method according to any of paragraphs.11-12, in which the short-circuit rods (2) consist of copper, short rods (2) before casting short rings (3) invest in other grooves sheet package (1) rotor and remaining after laying cage rods (2) in the other groove of the residual cross-section of the filled mold weight when casting short rings (3).



 

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3 dwg

FIELD: electricity.

SUBSTANCE: motor consists of body with stator with low and high speed windings mounted in slots, rotor fixed at motor shaft and box of inputs with through joints connected to outputs of specified windings. According to invention winding changeover device is located at motor body; input terminals of the motor should have facilities for connection of feeder current-carrying leads and output terminals of winding changeover device should be connected electrically with through joints connected to outputs of motor windings. Winding changeover device can be located in box of inputs; for this purpose two outputs of this device should be connected through its break-type contacts to outputs of low speed windings of the motor and two outputs through normally open contacts of device should be connected to through joints, which are connected to high speed windings of the motor. Third outputs of low and high speed windings should be interconnected and then connected to the third through joint in box of motor inputs.

EFFECT: simplification of power supply system structure, improvement of control and protection, enhancement of reliability and operation of asynchronous double-speed motors due to their power supply by one cable and due to motor control and protection by one device instead of two devices.

2 cl, 2 dwg

FIELD: electricity.

SUBSTANCE: rotor of an asynchronous electric machine comprises a shaft, a ferromagnetic core fixed coaxially on the shaft - a magnetic conductor with an external surface in the form of a circular cylinder and an electric winding of "squirrel cage" type. At the same time according to this invention, the ferromagnetic core - magnetic conductor consists of longitudinal elements made of material having at least axial electroconductivity, besides, the longitudinal elements with the help of frontal conductors - links are electrically connected to each other only by their end parts, forming a winding of "squirrel cage" type.

EFFECT: considerable improvement of weight and dimension characteristics of an electric machine, reduced prime cost of its manufacturing, considerable reduction of teeth pulsations of the torque on the shaft of the asynchronous electric machine with a rotor made according to this invention.

10 cl, 2 dwg

FIELD: engines and pumps.

SUBSTANCE: in asynchronous motor the following is used: semi-open (up to 2.2 mm) rotor slots of special design without chamfer with transition at the height of 1 mm to wide part of the slot top; stator slots having upper part of arched design and maximum opening up to 4 mm on condition that number of pairs of poles 2p = 6 - 12 is chosen so that frequency of supply voltage is not lower than 4 Hz, with rigid matching of ratio of numbers of rotor slots of 66-130 and stator slots of 54 - 108 at the number of rotor slots more than number of stator slots by 20%; stator winding with number of slots per pole and phase is at least 2; magnetic system made from steel having high values of induction without connection to value of specific losses.

EFFECT: higher energy data and overload capacity of electric motor, including at its operation in generator mode.

2 dwg, 1 tbl

FIELD: electricity.

SUBSTANCE: low-speed asynchronous electric motor includes stator with multi-phase winding and rotor with interleaved core and short-circuited winding. Stator phases are made in the form of annular windings coaxial with rotor, each of which is located between two annular magnetic cores with teeth protruding in axial direction and which are opposite directed. At that, annular magnetic cores of the phase are offset relative to each other through π/z angle, and between them there arranged is toroidal magnetic core, and annular magnetic core of various phases are offset relative to each other through 2π/z·m angle, where z - the number of teeth of each annular magnetic core, and m - the number of phases.

EFFECT: simplifying the manufacturing procedure of the stator windings at simultaneous technically possible increase of the number of poles of low-speed asynchronous electric motor.

3 dwg

FIELD: electricity.

SUBSTANCE: in the proposed electric motor containing stator (2) with single-phase winding (6) and rotor (13) with squirrel cage (24), stator (2) has magnetic core (3) and magnetic core (4), the symmetry axes of which are parallel to each other and perpendicular to rotor (13) rotation axis; poles (5) of magnetic core (3) lie in its symmetry axis, magnetic core (4) is ring-shaped and has one pair of poles (11) on inner side of the ring; angle between symmetry axis of each pole (11) and symmetry axis of magnetic core (4) lies within 15° to 75°; on poles (11) there arranged is winding (12) in the form of coil wound on spiral; on the part of magnetic core (4), which is opposite to poles (11), there is winding (9) representing the coil wound on spiral; windings (9) and (12) are connected to each other so that the direction of their coiling is the same; rotor (13) is located between poles (5) and (11).

EFFECT: simplifying the design, improving operating reliability of electric motor, and reducing its operating costs.

2 cl, 3 dwg

FIELD: electricity.

SUBSTANCE: asynchronous motor with hollow short-circuit rotor includes hollow rotor and external stator with core and winding, as well as additional rotor installed on the shaft in the zone restricted with stator with possibility of rotation irrespective of hollow rotor, made from ring-shaped magnet radially magnetised with the number of pairs of poles, which is equal to the number of pairs of poles of stator winding, on which there pressed is thin-wall sleeve from conducting material, and hollow rotor is made in the form of thin-wall shell from conducting material.

EFFECT: increasing power coefficient and efficiency of asynchronous motor with hollow rotor without deterioration of its dynamic characteristics.

3 cl, 2 dwg

FIELD: electrical and electromechanical engineering; face-type induction machines having one stator and one rotor.

SUBSTANCE: proposed machine has stator ring-type magnetic cores carrying field winding, as well as squirrel-cage rotor, stator base endshield accommodating supporting sleeve, rotor disk, bearing assembly incorporating rotor shaft bearings, and thrust bearing. Stator base endshield is fixed in position by means of enclosing hollow cylinder with thrust bearing disposed on its inner surface and tightly fitted on one end to annular boss of hollow cylinder and on other end abuts against rotor disk. Up to three actuating mechanisms can be coupled with this machine.

EFFECT: enhanced diametric dimensions of stator and rotor cores, minimized air gap between them, enhanced loading capacity and operating reliability of machine.

1 cl, 1 dwg

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