KR20000007206A - Drive motor cooling structure of turbo compressor - Google Patents

Abstract

PURPOSE: A drive motor cooling structure of a turbo compressor is provided to improve the cooling efficiency of a motor by activating the flowing of the coolant flowed into a motor chamber. CONSTITUTION: A turbo compressor has:coolant inhaling pipes(P1,P2) respectively communicated with one side of a sealed container(10); a first and a second compressing chambers(11,12) installed on both sides of the sealed container to be communicated with each other; a motor chamber(13) installed in the middle; a drive shaft(30) inserted to the center of the rotor(120) of the motor(100); a first and a second impellers(40,50) fixed on both ends of the drive shaft to increase the motive energy of a coolant; and a radial bearing(60) and a thrust bearing(60) installed inside of the motor chamber.

Description

Drive motor cooling structure of turbo compressor

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a turbocompressor, and more particularly, to a drive motor cooling structure of a turbocompressor for improving the cooling efficiency of a motor by activating a flow of refrigerant flowing into a motor chamber.

In general, a compressor is a machine that compresses gas such as air or refrigerant gas by a rotary motion of a vane or a rotor or a reciprocating motion of a piston. It consists of a compressor mechanism for sucking and compressing gas.

Such a compressor is classified into a hermetic type or a separable type according to the arrangement of the power generating portion and the compression mechanism. Among them, the hermetic compressor in which the power generating portion and the compression mechanism are installed together in one hermetically sealed container is recomposed according to the structure for compressing the gas. It is divided into rotary, reciprocating, linear and scroll compressor.

The recently introduced turbo compressor rotates the impeller by the driving force of the motor, and sucks and compresses the gas by using the centrifugal force generated when the impeller rotates. FIG. 1 is a longitudinal sectional view showing an example of a conventional turbo compressor. .

As shown in the drawing, a conventional two-stage compression turbo compressor is normally sealed with a first compression chamber 11 communicating with an evaporator (not shown) and a second compression chamber 12 communicating with a condenser (not shown). It is formed on both sides of the container 10, the motor chamber 13 is formed in the inner center of the sealed container 10 is mounted with an axial type of brushless DC MOTOR (20), The first and second compression chambers 11 and 12 and the motor chamber 13 are communicated with each other by the first and second gas passages 14 and 15, and are coupled to the motor 20 to rotate. Both ends of the 30 are inserted into the first and second compression chambers 11 and 12, respectively, and at the ends thereof, the gas sucked while rotating in the first and second compression chambers 11 and 12, respectively, is compressed into two stages. The first and second impellers 40 and 50 are coupled to each other, and the radial beam for supporting the radial and axial directions of the drive shaft 30 is between the motor 20 and each of the impellers 40 and 50. The ring 60 and the thrust bearing 70 are coupled, respectively.

The first gas passage 14 is formed to communicate the motor chamber 13 and the first compression chamber 11, and the second gas passage 15 is the first compression chamber 11 and the second compression. It is formed so as to communicate with the chamber 12.

In addition, in the central portion of the sealed container 10, refrigerant suction pipes P1 and P2 extending from an evaporator (not shown) or an accumulator (not shown) of a conventional refrigerant cycle apparatus are sealed container 10 and the motor chamber 13. Are inserted through each other, and the other side wall of the motor chamber 13 facing the ends of the refrigerant suction pipes P1 and P2 discharges the refrigerant introduced into the motor chamber 13 into the first gas flow passage 14. Outflow holes 13a, 13b, 13c are formed.

The refrigerant suction pipes P1 and P2 are inserted at both outer sides of the motor 20 to minimize the flow resistance of the motor 20 by the refrigerant gas, and the outflow holes 13a, 13b, and 13c are also refrigerants. The gas is formed on both outer sides of the motor 20 so as to smoothly discharge the gas from the motor chamber 13.

On the other hand, the BMD motor 20 is a stator 21 and the rotor 22 are all formed in a disc shape, wherein the stator 21 is integral to the inner peripheral surface of the motor chamber 13 of the sealed container 10. On the other hand, the rotor 22 is arranged so as to alternate with the stator 21 is pressed into the drive shaft 30 by shrinkage or cold shrink, etc., the outer surface of both outer plates of the rotor 22 induction Flat yoke plates 23 for inducing magnetic flux are respectively attached.

In the figure, reference numeral 16, which is not described, is a discharge port.

The conventional two-stage compression turbocompressor configured as described above is operated as follows.

That is, when induction magnetism is generated in the motor unit 20 by the applied power, the drive shaft 30 rotates at high speed with the first and second impellers 40 and 50 by the induction magnetism. The refrigerant gas is sequentially sucked into each of the compression chambers 11 and 12 by the rotation of the impellers 40 and 50, and then sprayed in the form of a screw by the centrifugal force of each of the impellers 40 and 50, so that each diffuser 11a and 12a is rotated. Through each of the volute (11b, 12b) is introduced into, through the diffuser (11a, 12a) into the respective volute (11b, 12b) in the process of the refrigerant gas is converted into the compressed gas by the pressure head rise the discharge port It was discharged to the condenser (not shown) through 10b.

Here, the refrigerant flows from the evaporator (not shown) into the motor chamber 13 of the sealed container 10 through the refrigerant suction pipes P1 and P2 and circulates the motor chamber 13 to cool the motor 20. Later, it flows into the first impeller 40 through the outflow holes 13a, 13b, 13c and the first gas passage 14, and is dispersed by the first impeller 40 into the first compression chamber 11. It is sprinkled while being sprayed, and is sucked back into the second impeller 50 through the second gas flow path 15, and is completely compressed in two stages by the second impeller so that the refrigeration cycle apparatus (exactly, a condenser) To be discharged.

At this time, as shown in Figure 2a, through the refrigerant suction pipes (P1, P2), most of the refrigerant flowing into both sides of the motor 20 is in contact with both yoke plates of the disc-shaped motor 20, after heat exchange, The first gas passage 14 flows out through the outflow holes 13a and 13b formed at both sides of the motor chamber 13, and the remaining small amount of refrigerant gas is formed between the stator 21 and the rotor 22. After permeating through the air gap, the gas flowed out into the first gas passage 14 through the central outflow hole 13c.

In this way, most of the refrigerant flowing into the motor chamber 13 does not pass between the air gaps of the axial DC motor 20, and immediately after contacting the outer surface of the motor 20, the first gas flow path. Since it flowed out to 14, the flow path resistance by the refrigerant was minimized.

However, in the conventional turbocompressor as described above, most of the refrigerant flowing into the motor chamber 13 comes into contact with the plate-shaped yoke plates attached to the outer sides of the motor 20, so that the outflow holes 13a and 13b are opened. Immediately through the first gas flow passage 14, which is effective to minimize the flow resistance of the refrigerant during the rotation of the rotor 22, the fluid flow in the motor chamber 13 is lower than the turbulent flow In addition to being in the form of laminar flow having a heat transfer rate, the refrigerant introduced into the motor chamber 13 did not flow into the air gap of the motor 20, resulting in the motor 20 being overheated.

Therefore, the present invention has been made in view of the problems of the motor cooling structure of the conventional turbocompressor, the refrigerant flowing into the motor chamber is smoothly introduced into the air gap of the motor, as well as the flow path resistance to the rotational movement of the rotor at least It is an object of the present invention to provide a cooling structure for the drive motor of a turbocompressor that can cool the motor effectively while generating the

1 is a longitudinal sectional view showing an example of a conventional turbocompressor.

Figure 2a is a longitudinal cross-sectional view showing in detail the motor chamber in a conventional turbo compressor.

Figure 2b is a front view showing a yoke plate in a conventional turbo compressor.

Figure 3a is a longitudinal cross-sectional view showing in detail the motor compartment in the turbocompressor of the present invention.

Figure 3b is a front view showing a yoke plate in the turbocompressor of the present invention.

Explanation of symbols on the main parts of the drawings

100: axial type drive motor 110: stator

111: coil 120: rotor

121: magnet 130: yoke plate

120a, 130a: refrigerant through hole 130b: refrigerant flow generating pin

In order to achieve the object of the present invention, a disc-shaped rotor and a plurality of magnets are respectively mounted and fixed at regular intervals to the drive shaft rotatably installed in the sealed container, interposed between each of the rotor and In a drive motor of a turbocompressor comprising a stator fixed to a closed container by mounting several coils to face the magnet, and a yoke plate attached to outer surfaces of both outer plates of the rotor to induce magnetic flux; Refrigerant through-holes are respectively formed in the rotor and the yoke plate to allow the refrigerant gas of the motor chamber to flow into the gap between the rotor and the stator, and among them, the refrigerant gas of the motor chamber flows to the outer surface of the yoke plate. There is provided a drive motor cooling structure of a turbocompressor, each of which defines a refrigerant flow generating pin.

Hereinafter, a drive motor cooling structure of a turbo compressor according to the present invention will be described in detail with reference to an embodiment shown in the accompanying drawings.

Fig. 3A is a longitudinal sectional view showing the motor compartment in detail in the turbocompressor of the present invention, and Fig. 3B is a front view showing a yoke plate in the turbocompressor of the present invention.

As shown in the drawing, a turbocompressor equipped with a drive motor cooling structure of the present invention has refrigerant intake pipes P1 and P2 extending from an evaporator (not shown). The first and second compression chambers 11 and 12 are formed on both sides of the container 10 so as to communicate with each other, whereas in the center, the stator 110 and the rotor 120 are disc-shaped biaxial motors. A motor chamber 13 for mounting the 100 is formed, and a drive shaft 30 is press-fitted to the center of the rotor 120 of the motor 100, and both ends of the drive shaft 30 are first and second. 2, the first and second impellers 40 and 50 are inserted into the compression chambers 11 and 12 to increase the kinetic energy of the refrigerant, and the radial direction of the drive shaft 30 and the inside of the motor chamber 13 are fixed. A radial bearing 60 and a thrust bearing 70 for supporting the axial direction are provided.

The motor chamber 13 communicates with the first compression chamber 11 by the first gas passage 14, and the first compression chamber 11 is connected by the second gas passage 15 with the second compression chamber ( 12, the second compression chamber 12 is formed with a discharge port 16 in communication with a conventional refrigeration cycle device.

In addition, refrigerant suction pipes P1 and P2 are inserted into both outer sides of the motor 100 at one side of the motor chamber 13, and the other side of the motor chamber 13 opposite to the refrigerant suction pipes P1 and P2 is provided. The outflow holes 13a, 13b, 13c communicating with the one gas flow passage 14 are formed.

On the other hand, the axial type BCD motor 100 of the drive motor is interposed between the stator 110 and a plurality of coils 111 are fixed to the sealed container 10, the stator 110. In addition, a plurality of magnets 121 are mounted so as to face the coil 111 and are fixed to the drive shaft 30 at fixed intervals, respectively, and a disc-shaped rotor 120 and both outer plates of the rotor 120. It is attached to the outer surface of the yoke plate 130 to induce a magnetic flux, the rotor 120 and the yoke plate 130 is formed with a plurality of refrigerant through holes (120a, 130a) in communication in the circumferential direction, respectively, In the outer surface of the yoke plate 130, several refrigerant flow generating pins 130b for stirring the refrigerant gas in the motor chamber 13 to form turbulent flow have a predetermined curvature in the rotational direction of the rotor 120. It is curved so as to have each projecting formed.

In the drawings, the same reference numerals are given to the same parts as in the prior art.

The general operation of the turbocompressor with the drive motor cooling structure of the present invention as described above is the same as in the prior art.

That is, the drive shaft 30 and the impellers 40 and 50 are rotated by the applied power, and the refrigerant flows into the motor chamber 13 from the evaporator (not shown) through the refrigerant suction pipes P1 and P2. The refrigerant flows into the first gas passage 14 through the outlet holes 13a, 13b, and 13c after cooling the motor 100, and the refrigerant introduced into the first gas passage 14 is cooled. The gas is temporarily compressed while being scattered into the first compression chamber 11 by the first impeller 40, and the compressed gas is compressed again through the second gas passage 15 to the second impeller 50. ) Is completely compressed into two stages in the second compression chamber 12 and discharged to a refrigeration cycle apparatus (exactly, a condenser).

Here, the refrigerant ejected from the evaporator (not shown) of the refrigeration cycle apparatus is directly introduced to both sides of the motor chamber 13 through the refrigerant suction pipes (P1, P2), the majority of the refrigerant flowing into the motor chamber (13). Is in contact with the rotor plate 120, the side plates 121 and 122 of the motor 100, and after being heat exchanged, flows out to the first gas passage 14 through the outflow holes 13a, 13b, and 13c, and the remaining amount of the motor Each air gap of the 100 is traversed and then flows out to the first gas passage 14.

At this time, the outer surface of each of the yoke plate 130 attached to both outer plates of the rotor 120 is formed with a plurality of refrigerant flow generating pins 130b bent in the rotation direction of the rotor 120, respectively As shown in 3a and 3b, the refrigerant flowing into the motor chamber 13 during the high-speed rotation of the drive shaft 30 is stirred at both sides of the motor 100 to form a turbulent flow, the refrigerant gas and the motor 100 Convection heat transfer is generated by active movement of the refrigerant gas with direct thermal conduction between the wires, and the cooling of the motor 100 is smoothly performed by such heat conduction and convective heat transfer.

In addition, since the rotor 120 and the yoke plate 130 have a plurality of refrigerant through holes 120a and 130a, respectively, a part of the refrigerant gas flowing into the motor chamber 13 is the refrigerant through holes 120a and 130a. Through the smooth flow into the air gap of the motor 100 is circulated.

On the other hand, since the surface area of the motor 100 in contact with the refrigerant is widened by the refrigerant flow generating pin (130a) is also improved thermal conductivity.

As described above, the drive motor cooling structure of the turbocompressor according to the present invention includes a disc-shaped rotor and its rotor interposed alternately between each of the disc-shaped stators coupled to the sealed container. A disk-shaped yoke plate coupled to both outer surfaces is formed to communicate with refrigerant through holes for allowing refrigerant gas in the motor chamber to flow into the gap between the rotor and the stator, wherein the yoke plate has an outer surface of the motor chamber. By forming several refrigerant flow generating pins for flowing the refrigerant gas, the refrigerant flowing into the motor chamber flows smoothly into the air gap between the rotor and the stator, and generates a minimum flow resistance for the rotational movement of the rotor. At the same time, the motor can be cooled effectively.

Claims (1)

A disc-shaped rotor is fixed to a drive shaft rotatably installed in a sealed container at several intervals, each of which is mounted with a plurality of magnets interposed therebetween, and several coils are mounted to face the magnet. In a drive motor of a turbocompressor comprising a stator fixed to a sealed container and a yoke plate attached to outer surfaces of both outer plates of the rotor to induce magnetic flux; Refrigerant through-holes are respectively formed in the rotor and the yoke plate to allow the refrigerant gas of the motor chamber to flow into the gap between the rotor and the stator, and among them, the refrigerant gas of the motor chamber flows to the outer surface of the yoke plate. Cooling motor drive structure of the turbocompressor, characterized in that the refrigerant flow generating pins are formed respectively.