JP2019022257A - Rotary electric machine - Google Patents

Abstract

To provide a rotary electric machine capable of enhancing a cooling performance and saving cost of manufacture while suppressing an internal pressure loss or electric property reduction.SOLUTION: The present invention relates to a rotary electric machine 1 comprising a rotor 20 and a stator 10. The rotor 20 includes: axial coolant channels 214 which are provided while facing the rotor at both sides in an axial direction and directed from both end sides of the rotor in the axial direction to a central part in the axial direction; multiple radial coolant channels 213 whose one end side is communicated to the axial coolant channels radially inside of the rotor and the other end side is opened on a peripheral surface of the rotor; and a partition wall part 211a which prevents the axial coolant channels from being communicated inside of the rotor.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a rotating electrical machine.

  In recent years, electric motors are used in place of conventional gas turbines in applications such as driving compressors. As an electric motor used for driving a compressor or the like, an induction motor including a rotor in which a plurality of rotor conductors provided in a slot of a rotor core are connected by end rings (short-circuit rings) at end faces of the rotor core, There is a permanent magnet type synchronous motor in which permanent magnets are arranged in the outer peripheral surface of a rotor core or a groove provided in the rotor core.

  Usually, in both induction motors and permanent magnet synchronous motors, the rotor core is formed by laminating electromagnetic steel plates having high magnetic permeability. When the electric motor is operated, centrifugal force acts on the rotor core, the rotor conductor, and the permanent magnet, and stress is generated in each part of the rotor. Due to this stress, each part of the rotor may be deformed or broken. Therefore, in order to reduce the stress acting on the rotor, the rotor is formed in a shape having an outer diameter as small as possible and long in the axial direction.

  On the other hand, although heat is generated in the electric motor due to electrical loss, the cooling performance of the central portion in the axial direction of the electric motor is reduced as the rotor becomes longer. For this reason, we are anxious about the increase in temperature accompanying the heat_generation | fever of the axial direction center part of an electric motor.

  Therefore, it is necessary to enhance the cooling performance in the electric motor. In order to reduce the temperature rise in the axial center of the motor, the stator core and the rotor core are each divided into a plurality of blocks (core packets) in the axial direction, and the radial direction and rotation of the stator core and the rotor core Ventilation paths are provided in the axial direction of the child core. The radial ventilation path is called a radial duct, and the axial ventilation path is called an axial duct.

  The cooling air passing through these ducts contributes to the cooling of the central portion in the axial direction of the electric motor. Therefore, in order to further improve the cooling performance of the electric motor, it is important to reduce the pressure loss generated in these ducts.

  In particular, in a two-pole or four-pole motor having a relatively high rotational speed, the pressure loss generated in the radial duct and the axial duct provided in the rotor is large, which is a factor of greatly reducing the cooling performance of the motor. . Therefore, reducing this pressure loss is an important issue in designing and manufacturing an electric motor.

  Here, Patent Literature 1 and Patent Literature 2 are known as techniques for improving the cooling performance of the electric motor. In the permanent magnet type synchronous motor of Patent Document 1, the rotor is skewed so that refrigerant flowing into the axial duct from both sides of the rotor in the axial direction does not collide with the axial center of the rotor, thereby preventing an increase in pressure loss. ing. In the rotating electrical machine of Patent Document 2, the axial center part of the shaft is processed so that refrigerant flowing into the axial duct from both axial sides of the rotor does not collide with the axial center part of the rotor to prevent an increase in pressure loss. To do.

JP 2014-193011 A JP 2010-104202 A

  In Patent Document 1, the rotor core is divided in the axial direction, and the divided rotor cores are skewed with each other, so that the electric characteristics are improved and the refrigerant passing through the axial duct collides with the center of the rotor. A technique for suppressing an increase in pressure loss caused by the above is described.

  However, in the case of an induction motor having a squirrel-cage conductor, since the rotor bar exists, the rotor cannot be discretely skewed, and therefore the technique of Patent Document 1 cannot be applied to the induction machine. Further, since the axial duct is provided at the center of the rotor core, the amount of use of the electromagnetic steel sheet in the center in the axial direction is reduced. For this reason, in the technique of patent document 1, the power factor fall of an electric motor is caused and the emitted-heat amount of the whole electric motor rises.

  In Patent Document 2, the axial center portion of the shaft is processed so that the refrigerant flowing into the axial duct from both axial sides of the rotor does not collide with the axial center portion of the rotor. An increase in pressure loss is suppressed.

  However, in Patent Document 2, since the shaft needs to be processed, the number of shaft processing steps increases, and the manufacturing cost of the entire rotating electrical machine increases. In Patent Document 2, an axial duct is provided between the rotor core and the shaft. In this case, however, the inner diameter of the rotor core needs to be increased. Therefore, during operation, the inner peripheral stress of the rotor core increases, and the rotor core may be damaged.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a rotating electrical machine that can suppress internal pressure loss and deterioration of electrical characteristics and improve cooling performance and manufacturing cost. There is.

  In order to solve the above problems, a rotating electrical machine according to the present invention is a rotating electrical machine having a rotor and a stator, and the rotor is provided facing the rotor on both sides in the axial direction, and the shaft of the rotor A plurality of axial refrigerant passages that respectively extend from both ends in the axial direction toward the axial center, one end side communicates with each axial refrigerant passage on the radially inner side of the rotor, and the other end side opens on the circumferential surface of the rotor And a partition wall for preventing the axial refrigerant channels from communicating with each other inside the rotor.

  According to the present invention, the refrigerant flows from the respective axial refrigerant flow paths of the rotor toward the center of the rotor, cools the rotor from the inside, and passes through the radial refrigerant flow path to surround the rotor. Flows out. Since the refrigerant flowing from each axial direction refrigerant flow path toward the axial center is blocked by the partition wall, it does not collide with the axial center. For this reason, the pressure loss of the flow path through which the refrigerant flows can be suppressed.

The fragmentary sectional view which looked at the rotary electric machine by 1st Example from the side. The arrow II-II direction sectional drawing in FIG. Explanatory drawing which shows the flow of the cooling air inside a rotary electric machine. The arrow IV-IV direction sectional drawing in FIG. Explanatory drawing which compares and shows the pressure loss in the axial direction center part of an axial duct with the case where this example is applied and the case where it does not apply. The fragmentary sectional view which looked at the rotary electric machine by 2nd Example from the side. The arrow VII-VII direction sectional drawing in FIG. The arrow VIII-VIII direction sectional drawing in FIG. The partial cross section perspective view of a rotary electric machine. The partial cross section perspective view which looked at the rotary electric machine by 3rd Example from the horizontal direction. The fragmentary sectional view which looked at the rotary electric machine by 4th Example from the side. The fragmentary sectional view which looked at the rotary electric machine by 5th Example from the side. The fragmentary sectional view which looked at the rotary electric machine by 6th Example from the side, and the enlarged view near an axial duct. The fragmentary sectional view which looked at the rotary electric machine by 7th Example from the side, and the enlarged view of axial duct vicinity. The fragmentary sectional view which looked at the rotary electric machine by 8th Example from the side, and the enlarged view near an axial duct. The fragmentary sectional view which looked at the rotary electric machine by 9th Example from the side, and the enlarged view near an axial duct. The fragmentary sectional view which looked at the rotary electric machine by 10th Example from the side, and the enlarged view of axial duct vicinity. The fragmentary sectional view which looked at the rotary electric machine by 11th Example from the side, and the enlarged view of axial duct vicinity.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. The rotating electrical machine of the present embodiment can be configured as a squirrel-cage induction motor, for example.

  As will be described in detail below, the rotating electrical machine of the present embodiment is a duct piece in which a rotor core is divided into a plurality of packets in the axial direction, and a flow path for flowing a refrigerant between the divided rotor cores is formed. And a plurality of axial refrigerant flow paths are installed in the rotor core. Furthermore, in the rotating electrical machine of the present embodiment, the number of axial refrigerant flow paths at the axial center of the rotor core is different from the number of axial refrigerant flow paths of the rotor core disposed at the axial end. The axial refrigerant flow path does not penetrate in the axial direction.

  Thereby, according to the rotary electric machine of this embodiment, the pressure loss inside a rotary electric machine can be reduced, the electrical characteristic of a rotary electric machine can be improved, and also the manufacturing man-hour and manufacturing cost of a rotary electric machine can be reduced.

  Embodiments will be described with reference to FIGS. FIG. 1 is a cross-sectional view of the rotating electrical machine 1 of this embodiment as viewed from the lateral direction. In the embodiment, the case where the rotor is an induction motor in which the rotor has a squirrel-cage conductor is shown. However, the rotor shape may be a permanent magnet motor having a permanent magnet, a synchronous motor having a field winding, a reluctance motor formed only by a core, or the like, and components and shapes for generating a magnetic field from the rotor Does not limit.

  The rotating electrical machine 1 includes, for example, a substantially cylindrical stator 10, a rotor 20 that is coaxially disposed in the stator 10, and a shaft 26 that is coaxially inserted through the rotor 20. Fans 31 are attached to regions projecting from the rotor 20 on both sides of the shaft 26.

  The stator 10 includes a stator core 11, a plurality of stator slots 12, and armature windings 13 wound around the stator slots 12. In the rotor 20, the rotor core 21 is connected to the shaft 26.

  As shown in FIG. 2, a plurality of rotor slots 22 are provided apart from each other in the circumferential direction on the outer peripheral portion of the rotor core 21, and rotor teeth 24 are provided between the rotor slots 22. ing. A rotor bar 23 is inserted into each rotor slot 22. Each rotor bar 23 is short-circuited by an end ring 25 located on the axial end surface of the rotor 20, thereby forming a cage conductor.

  Further, as shown in FIG. 2, a plurality of axial ducts 214 are formed in the inner peripheral portion of the rotor core 21 so as to surround the periphery of the shaft 26 and spaced apart by a predetermined pitch in the circumferential direction. The axial duct 214 is an example of an “axial refrigerant flow path”. In this embodiment, air around the rotating electrical machine 1 is used as the refrigerant.

  When the structure of the rotor 20 of the rotating electrical machine 1 is an induction motor, the shape of the rotor bar 23 is a rectangle as shown in FIG. 2, but the shape is not limited to this, and the corners are chamfered to be circular. Any shape may be used. The cross-sectional shape of the axial duct 214 is also trapezoidal in FIG. 2, but it may be circular or square in addition to the trapezoid, and the shape is not limited as long as soundness can be maintained in design.

  The stator core 11 and the rotor core 21 are formed, for example, by laminating laminated steel plates in the axial direction. The stator core 11 is divided into a plurality of stator core packets 111 arranged in the axial direction. Similarly, the rotor core 21 is also divided into a plurality of rotor core packets 211 arranged in the axial direction.

  A stator duct piece 112 is provided between the stator core packets 111. Thus, a stator radial duct 113 is formed between the adjacent stator core packets 111. Similarly, a rotor duct piece 212 is also provided between the rotor core packets 211. Thus, a rotor radial duct 213 is formed between the adjacent rotor core packets 211. The rotor radial duct 213 is an example of a “radial direction refrigerant flow path”.

  The electromagnetic steel sheet forming the rotor core 21 is fixed to the shaft 26 after being tightened from both sides in the axial direction so that the laminated steel sheets are not disassembled by the rotor core clamps 27 arranged at both axial ends of the rotor 20. Is done. The rotor core 21 may be attached by heating the rotor core 21 to widen the shaft insertion hole, inserting the shaft 26 into the shaft insertion hole, and then cooling the rotor core 21 (shrink fitting). ). Alternatively, the shaft 26 may be cooled, and the contracted shaft 26 may be inserted into the shaft insertion hole of the rotor core 21 and then attached after waiting for the shaft 26 to return to normal temperature (cool fit).

  Since it is necessary to pass cooling air through the inner periphery of the rotor core 21, the rotor core clamp 27 is also provided with an axial duct 214.

  In FIG. 1, the axial position of the stator radial duct 113 and the axial position of the rotor radial duct 213 are made to coincide with each other. For example, the stator radial duct 113 or the rotor radial duct 213 may be shifted by one width, or the stator radial duct 113 is located at the axial center position of one rotor core packet 211. You may arrange as follows.

  In FIG. 1, the axial radial dimensions of the stator radial duct 113 and the rotor radial duct 213 are shown as being the same, but the axial width dimensions are not necessarily the same. The axial width dimension of the stator radial duct 113 may be larger or smaller than the axial width dimension of the rotor radial duct 213.

  FIG. 3 shows the flow of cooling air inside the rotating electrical machine 1. Cooling air inside the rotating electrical machine 1 is generated by cooling fans 31 that are located on both axial sides of the rotor core 21 and attached to the shaft 26. As shown in FIG. 3, the cooling air generated by each fan 31 is cooled while passing through the interior of the rotating electrical machine 1 through three paths (A1) to (A3).

  (A1) In the first path A1, after the cooling air flows into the axial duct 214 of the rotor 20, the rotor radial duct 213, the outer peripheral surface of the rotor core 21, and the inner peripheral surface of the stator core 11 Passing through the gap 14 between them and the stator radial duct 113, the air cooler 2 is reached. Hereinafter, this is referred to as a route (A1).

  (A2) In the second path A2, the cooling air flows from the gap 14 to the axial center of the stator core 11, passes through the stator radial duct 113, and then reaches the air cooler 2. Hereinafter, this is referred to as a route (A2).

  (A3) In the third path A3, the cooling air does not flow into the axial duct 214 and the gap 14, but passes through the surface of the end portion of the armature winding 13, and the gap between the stator core 11 and the frame 3 To reach the air cooler 2. This is called a route (A3).

  When the cooling air passing through the paths (A1) to (3) passes through the armature winding 13 and the rotor bar 23, the armature winding 13 is cooled by heat transfer. The cooling air also exchanges heat with the stator core 11 when passing through the stator radial duct 113. Here, since the armature winding 13 is installed in the stator slot 12 provided in the stator core 11, the armature winding 13 is in thermal conduction with the stator core 11. Therefore, the armature winding 13 is also cooled indirectly through the stator core 11.

  Among the above paths (A1) to (A3), particularly the cooling air passing through the path (A1) passes through both the armature winding 13 and the rotor bar 23 that generate the most heat in the rotary electric machine 1. The component that contributes most to the cooling performance of the rotating electrical machine 1. In the path (A1), in addition to the cooling air generated from the fan 31, cooling air is also generated from the rotor bar 23 and the rotor duct piece 212 installed in the rotor core 21. Therefore, in order to improve the cooling performance of the rotating electrical machine 1, it is necessary to suppress the pressure loss of the path (A1) and increase the flow rate (flow rate) of the cooling air as the refrigerant flowing in the rotating electrical machine 1. .

  The cooling air in the path (A1) is generated from the fans 31 installed on both sides of the rotor 20, and then flows into the axial ducts 214 from both axial sides of the rotor 20, and is divided into a plurality of rotor radial ducts 213. It flows in the radial direction while flowing.

  At this time, the position where the draft resistance becomes the largest is the inside of the axial duct 214, the inside of the rotor radial duct 213, and the place where the rotor axial duct 214 divides into the rotor radial duct 213.

  Here, if the cooling air flowing in from the axial both sides of the axial duct 214 (left and right sides in the drawing) collide with each other at the axial center in the axial duct 214, a large pressure loss occurs. Therefore, in order to improve the cooling performance of the rotating electrical machine 1, it is preferable to reduce the pressure loss at the axial center of the axial duct 214 as much as possible.

  Therefore, in this embodiment, the number of the axial ducts 214 at the axial center is smaller than that at the axial end, and a structure in which the rotor axial duct 214 does not penetrate in the axial direction is adopted.

  In other words, as shown in FIG. 2, this characteristic structure is a structure in which none of the axial ducts 214 is provided in the rotor core packet 211a disposed in the central portion in the axial direction. That is, in the present embodiment, among the rotor core packets 211, a predetermined rotor core packet 211a located in the axial center portion is caused to function as a partition portion for interrupting the axial duct 214 halfway. With this structure, it is possible to form the ventilation path (A1) so that the cooling air flowing into the rotor axial duct 214 from both sides in the axial direction does not collide with each other at the axial center of the rotor axial duct 214.

  As a result, in this embodiment, it is possible to obtain a cooling air flow (A1) in which the cooling air flowing in from the axial end portion of the rotor 20 does not cancel each other, and to reduce the pressure loss in the axial duct 214. Can do.

  FIG. 5 shows the pressure loss at the axial center in the axial duct 214 for the present embodiment and the comparative example. Assuming that the air volume is constant, the pressure loss at the axial center portion of the axial duct 214 in the structure according to the present embodiment is reduced to about half compared to the comparative example in which the axial duct 214 passes. Therefore, according to the present embodiment, since the air volume in the axial duct 214 is increased, the cooling performance of the rotating electrical machine 1 is improved.

  Further, in the present embodiment, only the predetermined rotor core packet 211a located at the axial center portion of the electromagnetic steel sheet (rotor core packet 211) forming the rotor core 21 is not formed with the axial duct 214. The electromagnetic steel sheet is left as it is. Thereby, the predetermined rotor core packet 211a functions as a partition wall portion that does not allow the axial duct 214 to penetrate in the axial direction.

  Therefore, in the predetermined rotor core packet 211a at the axial center, the amount of use of the electromagnetic steel sheet increases, so that the power factor of the rotating electrical machine 1 is improved as compared with the case where the axial duct 214 is formed.

  Furthermore, in patent document 2, in order to prevent the collision of the cooling air in the axial center part of an axial duct, a partition plate may be welded between the inner diameter side of the rotor core in the axial center part and the shaft. On the other hand, in the structure of the present embodiment, the partition plate at the axial center is not required, and therefore the number of manufacturing steps can be reduced as compared with the technique 2 of Patent Document 2.

  Furthermore, in this embodiment, since a special partition plate is not required, the shaft 26 can be directly connected to the rotor core 21. Therefore, according to the present embodiment, the shaft 26 can be formed as a rounded shaft. Thereby, compared with the structure of patent document 2, a manufacturing man-hour can be reduced further and the manufacturing cost of the rotor 20 can be reduced.

  A second embodiment will be described with reference to FIGS. In the following embodiments including the present embodiment, differences from the first embodiment will be mainly described.

  FIG. 6 shows a cross section of the rotating electrical machine 1b according to the present embodiment as seen from the lateral direction. In this embodiment, among the rotor core packets 211 constituting the rotor core 21, the rotor core packets 211b1 and 211b2 located adjacent to the axial center are used as predetermined rotor core packets.

  In this embodiment, the number of the axial ducts 214 of the predetermined rotor core packets 211b1 and 211b2 is smaller than the number of the axial ducts 214 formed in the other rotor core packets 211, and the rotor core packets 211b1 and the rotations are rotated. The circumferential positions of the axial ducts 214 of the child core packets 211b2 are arranged to be staggered.

  7 is a cross-sectional view of the first predetermined rotor core packet 211b1 as seen from the direction of arrows VII-VII in FIG. FIG. 8 is a cross-sectional view of the second predetermined rotor core packet 211b2 as seen from the direction of arrows VIII-VIII in FIG. FIG. 9 shows a path of cooling air that passes through the axial duct 214 and the radial duct 213 in the present embodiment.

  In the figure, reference numeral 214b1 is attached to the axial duct formed in the first predetermined rotor core packet 211b1. Similarly, reference numeral 214b2 is assigned to the axial duct formed in the second predetermined rotor core packet 211b2. The axial ducts 214b1 and 214b2 are referred to as the axial duct 214 unless otherwise distinguished.

  As shown in FIGS. 7 and 8, the rotor core packet 211b1 and the rotor core packet 211b2 have the same number of axial ducts 214 formed and the circumferential pitch of the axial ducts 214 is the same. However, the rotor core packet 211b1 and the rotor core packet 211b2 are different in the circumferential position of the axial duct 214.

  A simple example will be described. When a total of 12 axial ducts 214 are formed in the predetermined rotor core packets 211b1 and 211b2 so as to be separated by 30 degrees in the circumferential direction, the first predetermined rotor core packet 211b1 includes 60 in the circumferential direction. A total of six axial ducts 214b1 that are spaced apart from each other are formed. Similarly, a total of six axial ducts 214b2 are formed in the second predetermined rotor core packet 211b2 so as to be separated by 60 degrees in the circumferential direction. The first predetermined rotor core packet 211b1 and the second predetermined rotor core packet 211b2 are arranged so as to be shifted by 30 degrees in the circumferential direction so that the axial ducts 214b1 and 214b2 do not overlap and communicate with each other. The

  As a result, as shown in the perspective view of FIG. 9, each axial duct 214 does not penetrate in the axial direction of the rotor 20, and is interrupted by one of the predetermined rotor core packets 211 b 1 or 211 b 2. Therefore, the cooling air flowing in the axial duct 214 does not collide at the axial center of the axial duct 214, and the momentum does not cancel each other.

  As shown in FIG. 9, in this embodiment, the position of the axial duct 214b1 in the first predetermined rotor core packet 211b1 and the position of the axial duct 214b2 in the second predetermined rotor core packet 211b2 are in the circumferential direction. Therefore, in the axial duct 214b1, the path of the cooling air flowing from the left side in the axial direction is approximately one rotor core packet longer than the path of the cooling air flowing from the right side in the axial direction.

  On the other hand, in the axial duct 214b2, on the contrary to the axial duct 214b1, the path of the cooling air flowing from the right side in the axial direction is approximately one rotor core packet longer than the path of the cooling air flowing from the left side in the axial direction.

  Therefore, the total length of the path through which the cooling air passes through each axial duct 214b1, 214b2 and each rotor radial duct 213 is equal to or less than that of the comparative example through which the axial duct passes. Thereby, the pressure loss corresponding to the axial duct in the axial center portion in the comparative example is reduced in this embodiment.

  Configuring this embodiment like this also achieves the same operational effects as the first embodiment. In the present embodiment, the cooling air does not collide at the axial center of the axial duct 214, and the pressure loss in the axial duct 214 is reduced to be equal to or less than that in the first embodiment. For this reason, in the present embodiment, as in the first embodiment, it is possible to obtain the effect of improving the cooling performance by reducing the pressure loss, and it is also possible to obtain the effect of improving the power factor by increasing the usage amount of the electromagnetic steel sheet.

  Note that since the shapes of the axial ducts 214b1 and 214b of the rotor core packets 211b1 and 211b2 are the same, only one type of die is required when forming the axial duct 214 on the rotor core 20. Therefore, in this embodiment, the man-hour increase accompanying the increase in the type of the rotary core 20 does not occur, and only the man-hour reduction effect of the axial duct manufacturing can be obtained. Therefore, the present embodiment can obtain the effect of reducing the manufacturing cost as in the first embodiment.

  A third embodiment will be described with reference to FIG. FIG. 10 shows a cross section of the rotating electrical machine 1b1 according to this embodiment as viewed from the lateral direction and the flow of cooling air. In the second embodiment, the case has been described in which an even number of predetermined rotor core packets 211b1 and 211b2 are provided at the axial center of the rotor 20.

  In contrast, in the present embodiment, a case where an odd number of predetermined rotor core packets are arranged at the axial center of the rotor 20 will be described. In this case, between the rotor core packet 211b1 and the rotor core packet 211b2, a rotor core packet 211 having the same shape as that of a normal rotor core packet 211 (a rotor core packet other than a predetermined rotor core packet). May be arranged. That is, three rotations of the first predetermined rotor core packet 211b1, the normal rotor core packet 211, and the second predetermined rotor core packet 211b2 are provided at the axial center of the rotor 20. The child core packet is arranged so that the axial duct 214 does not communicate in the axial direction.

  Configuring this embodiment like this also achieves the same operational effects as the second embodiment. In the present embodiment, only the rotor core packet 211 having the same shape as the rotor core packet 211 located at the end in the axial direction is disposed between the rotor core packet 211b1 and the rotor core packet 211b2. For this reason, this embodiment can also obtain the effect of reducing the pressure loss, improving the power factor, and reducing the production cost without increasing the number of manufacturing steps.

  A fourth embodiment will be described with reference to FIG. FIG. 11 shows a cross section of the rotating electrical machine 1c according to this embodiment as seen from the lateral direction. In each of the above embodiments, each rotor core packet 211 has the same axial length dimension. On the other hand, as shown in FIG. 11, the axial length of each rotor core packet 211 may be non-uniform.

  In the rotating electrical machine 1c according to the present embodiment, a plurality of predetermined rotor core packets 211c1 and 211c2 are arranged in the center in the axial direction, and the axial ducts 214c1 and 214c2 are blocked so as not to communicate with each other. The rotor core packets 211c1 and 211c2 have the same configuration as the above-described rotor core packets 211b1 and 211b2 except for the length in the axial direction thereof, and thus further description thereof is omitted.

  In the rotating electric machine, the armature winding 13 and the rotor bar 23 in the central portion in the axial direction are usually the highest temperature. For this reason, it is necessary to feed as much cooling air as possible into the axial center of the rotor 20.

  Therefore, in the rotating electrical machine 1c of the present embodiment, as shown in FIG. 11, the axial length dimensions (thicknesses) of the rotor core packets 211c1, 211c2, 211c11, and 211c21 located near the axial center of the rotor 20 are provided. ), And the axial length of the other rotor core packet 211 is increased.

  More specifically, each rotor core packet 211 is set such that its axial length becomes shorter as it approaches the axial center of the rotor 20. In the illustrated example, the predetermined rotor core packet 211c1, 211c2 located at the axial center of the rotor 20 is the thinnest, and the rotor core packet adjacent to the outer side of the predetermined rotor core packet 211c1, 211c2 in the axial direction. 211c11 and c21 are the next thinnest, and the other rotor core packet 211 adjacent to the outside in the axial direction is set to be the thickest.

  Configuring this embodiment like this also achieves the same operational effects as the respective embodiments. Furthermore, in this embodiment, the axial thickness of each rotor core packet 211 is made non-uniform, and a large number of rotor radial ducts 213 are arranged in the axial center of the rotor 20. The flow rate of the cooling air can be increased, and the armature winding 13 and the rotor bar 23 can be effectively cooled.

  A fifth embodiment will be described with reference to FIG. FIG. 12 shows a cross section of the rotating electrical machine 1d according to the present embodiment as seen from the lateral direction. In the rotating electrical machine 1d of the present embodiment, just as described in the first embodiment, only one predetermined rotor core packet 211d is disposed at the center in the axial direction. Furthermore, in the rotating electrical machine 1d of the present embodiment, as described in the fourth embodiment, the axial length dimension of each rotor core packet 211 is uneven, and the closer to the axial center of the rotor 20, The rotor core packet 211 is set to be thin.

  Configuring this embodiment like this also exhibits the same effects as the fourth embodiment. That is, according to the present embodiment, the rotor radial duct 213 can be centrally arranged in the axial center portion of the rotor 20, the amount of cooling air in the axial center portion of the rotating electrical machine 1 can be increased, The cooling effect of the armature winding 13 and the rotor bar 23 can be improved.

  A sixth embodiment will be described with reference to FIG. FIG. 13 shows a cross section of the rotating electrical machine 1b2 according to this embodiment as seen from the lateral direction. In the rotating electrical machine 1b2 of the present embodiment, an even number of predetermined rotor core packets 211b1 and 211b2 are arranged at the axial center of the rotor 20 in the same manner as the rotating electrical machine 1b described in the second embodiment. The axial ducts 214b1 and 214b2 are blocked from communicating in the axial direction by the rotor core packets 211b1 and 211b2.

  In the present embodiment, in each of the rotor core packets 211 other than the predetermined rotor core packets 211b1 and 211b2, a tapered portion 215 that changes relatively smoothly is provided at a portion where the flow is divided from the axial duct 214 to the rotor radial duct 213. Provide.

  For example, the diameter of the tapered portion 215 gradually increases toward the cooling air flow direction in the vicinity of the outlet of the axial duct 214 among the rotor core packets 211 other than the predetermined rotor core packets 211b1 and 211b2. It is formed so as to increase.

  As described above, in this embodiment, by providing the tapered portion 215 at the position where the axial duct 214 and the rotor radial duct 213 are connected, a rapid direction when the cooling air flows from the axial duct 214 to the rotor radial duct 213 is provided. Suppress changes.

  Here, when the flow direction of the fluid such as air or water changes abruptly, the flow of the fluid is separated and the loss factor of the fluid increases, so that the pressure loss increases. The pressure loss is proportional to the size of the fluid separation area. Therefore, in order to reduce the pressure loss of the fluid, it is necessary to have a structure in which the separation region of the fluid is as small as possible and the flow of the cooling air does not change as rapidly as possible.

  Configuring this embodiment like this also achieves the same operational effects as the respective embodiments. Furthermore, according to the present embodiment, it is possible to suppress a sudden change in the flow of the cooling air when flowing from the axial duct 214 into the rotor radial duct 213, thereby reducing pressure loss. Thereby, in a present Example, the ventilation rate in a path | route (A1) increases and the cooling performance of the rotary electric machine 1 improves.

  A seventh embodiment will be described with reference to FIG. FIG. 14 is a cross-sectional view of the rotating electrical machine 1b3 according to the present embodiment as seen from the lateral direction. The rotating electrical machine 1b3 of the present embodiment corresponds to a modification of the rotating electrical machine 1b2 described in FIG.

  In the rotating electrical machine 1b3 of the present embodiment, the tapered portion 216 is formed in a step shape. Configuring this embodiment like this also achieves the same operational effects as the sixth embodiment.

  The eighth embodiment will be described with reference to FIG. FIG. 15 is a cross-sectional view of the rotating electrical machine 1b4 according to this embodiment as seen from the lateral direction. The rotating electrical machine 1b4 of the present embodiment corresponds to a modification of the rotating electrical machine 1b2 described in FIG.

  In the rotating electrical machine 1b4 of this embodiment, the taper portions 215 (1) to 215 (4) of each rotor core packet 211 are formed so as to increase in diameter toward the axial center portion of the rotor 20. Configuring this embodiment like this also achieves the same operational effects as the sixth embodiment.

  A ninth embodiment will be described with reference to FIG. FIG. 16 is a cross-sectional view of the rotating electrical machine 1b5 according to the present embodiment as seen from the lateral direction. The rotating electrical machine 1b5 of this embodiment corresponds to a modification of the rotating electrical machine 1b2 described in FIG.

  In the rotating electrical machine 1b5 of the present embodiment, the tapered portion 215 is only at a place where the cooling air flowing through the axial ducts 214b1 and 214b2 toward the axial center of the rotor 20 is prevented from going straight by the predetermined rotor core packets 211b1 and 211b2. Form.

  As described above, even when the tapered portion (corner portion) is provided only in the axial center portion of the rotor 20 at the portion where the axial duct 214 branches to the rotor radial duct 213, the same effect as the sixth embodiment is obtained. Play. Furthermore, in the rotating electrical machine 1b5 of the present embodiment, since the air volume at the axial center increases compared to the structure described in FIG. 15 and FIG. 16, when applied to a model that further enhances cooling of the axial center. Good.

  A tenth embodiment will be described with reference to FIG. FIG. 17 shows a cross section of the rotating electrical machine 1e according to the present embodiment as viewed from the lateral direction. The rotating electrical machine 1e of the present embodiment is provided with one predetermined rotor core packet 211a at the axial center of the rotor 20, similar to the rotating electrical machine 1 of the first embodiment, and this predetermined rotor. The core packet 211a prevents each axial duct 214e from penetrating in the axial direction.

  And the axial duct 214e of a present Example is formed so that a diameter may be gradually expanded as it goes to the axial direction center part from the axial direction edge part (inlet side) of the rotor 20. FIG.

  It is known that the pressure loss is proportional to the square of the wind speed. Therefore, with the structure shown in FIG. 17, the flow passage area of the axial duct 214e increases at the axial center of the rotor 20, and the wind speed of the cooling air decreases. For this reason, the pressure loss in the axial duct 214e further decreases.

  Further, since the wind speed of the cooling air in the axial duct 214e is reduced, the pressure loss when diverting from the axial duct 214e to the rotor radial duct 213 is also reduced. Thereby, since the pressure loss in the path | route (A1) in the rotor 20 is reduced, the ventilation rate of the whole rotary electric machine 1e increases, and it can improve cooling performance.

  An eleventh embodiment will be described with reference to FIG. FIG. 18 is a cross-sectional view of the rotating electrical machine 1f according to the present embodiment as seen from the lateral direction. In the rotating electrical machine 1 f of the present embodiment, a guide portion 271 is formed on the rotor core clamp 27 in addition to the configuration of the rotating electrical machine 1 described in the first embodiment.

  An axial duct 214 is also formed on the rotor core clamp 27 installed at the end of the rotor 20 in the axial direction. The axial duct 214 is gradually contracted toward the inlet of the axial duct 214 in the direction of the cooling air. A tapered guide portion 271 is formed to have a diameter. As described above, a large pressure loss occurs when the direction of flow of the fluid changes abruptly.

  Therefore, in this embodiment, the shape of the axial duct 214 is not the same at the inlet portion and the axial center, and gradually decreases in the direction of the cooling air so that the flow of the cooling air does not change rapidly. Such a guide portion 271 is provided on the inlet side of the axial duct 214. By adopting this structure, pressure loss at the inlet portion of the axial duct 214 can be reduced, the air flow rate of the entire rotating electrical machine 1f can be increased, and the cooling performance can be improved.

  In addition, this invention is not limited to embodiment mentioned above. A person skilled in the art can make various additions and changes within the scope of the present invention. In the above-described embodiment, the present invention is not limited to the configuration example illustrated in the accompanying drawings. The configuration and processing method of the embodiment can be changed as appropriate within the scope of achieving the object of the present invention.

  Moreover, each component of the present invention can be arbitrarily selected, and an invention having a selected configuration is also included in the present invention. Further, the configurations described in the claims can be combined with combinations other than those specified in the claims.

  1, 1b, 1c, 1d, 1e, 1f: rotating electric machine, 10: stator, 11: stator core, 20: rotor, 21: rotor core, 211: rotor core packet, 211a, 211b, 211c, 211d, 211e: predetermined rotor core packets,

Claims (11)

A rotating electric machine having a rotor and a stator,
The rotor includes
An axial refrigerant flow path that is provided opposite to the rotor on both sides in the axial direction and that extends from both axial ends of the rotor toward the axial center,
One end side communicates with each of the axial refrigerant flow paths on the radial inner side of the rotor, and the other end side has a plurality of radial refrigerant flow paths opened to the circumferential surface of the rotor;
A partition wall for preventing the axial refrigerant flow paths from communicating with each other inside the rotor;
Rotating electric machine. The rotor is
A plurality of disk-shaped rotor packets stacked in the axial direction;
A rotor clamp for clamping each rotor packet in the axial direction from both axial ends of the rotor;
A duct piece that is provided between the rotor packets, and that forms the radial refrigerant flow path between the rotor packets for flowing the refrigerant in the radial direction of the rotor;
The axial direction refrigerant flow formed in the axial direction refrigerant flow path that is formed in the respective rotor clamps and the respective rotor packets so as to be separated from each other in the circumferential direction, and communicates with other adjacent axial direction refrigerant flow paths. Road,
Among the rotor packets, the rotor packet is a predetermined rotor packet located in the central portion of the rotor in the axial direction, and functions as the partition wall portion for preventing the axial refrigerant flow passages located on both sides from communicating with each other. The predetermined rotor packet;
The rotating electrical machine according to claim 1, comprising: The predetermined rotor packet includes a predetermined rotor packet on one side and a predetermined rotor packet on the other side,
Each of the other rotor packets excluding the predetermined rotor packet on the one side and the predetermined rotor packet on the other side is provided with a plurality of the axial refrigerant flow paths spaced apart at a predetermined pitch in the circumferential direction. And
The predetermined rotor packet on one side is provided with an axial refrigerant flow path that is spaced apart in the circumferential direction at a pitch that is twice the predetermined pitch among the axial refrigerant flow paths.
In the predetermined rotor packet on the other side, the axial refrigerant flow other than the axial refrigerant flow path provided in the predetermined rotor packet on the one side among the axial refrigerant flow paths. There is a road,
The rotating electrical machine according to claim 2. At least one rotor packet having the same structure as that of the other rotor packet is disposed between the predetermined rotor packet on the one side and the predetermined rotor packet on the other side.
The rotating electrical machine according to claim 3. The axial length of at least some of the rotor packets among the rotor packets is different from the axial length of the other rotor packets.
The rotating electrical machine according to any one of claims 2 to 3. The axial length of each rotor packet is set to be shorter from the both end sides of the rotor toward the axial center.
The rotating electrical machine according to claim 5. The axial refrigerant flow path is formed such that the flow path area increases from the both end sides of the rotor toward the axial center of the rotor.
The rotating electrical machine according to claim 6. The axial refrigerant flow path is formed so that the flow path area increases as it goes toward the axial center of the rotor in the same rotor packet.
The rotating electrical machine according to claim 7. The axial refrigerant flow path is formed so that the flow path area increases for each rotor packet as it goes toward the axial center of the rotor.
The rotating electrical machine according to claim 7. The rotor clamp is provided with a tapered portion in which the flow passage area gradually decreases toward the inlet side of the axial refrigerant flow passage.
The rotating electrical machine according to claim 9. In a region connecting the axial direction refrigerant flow path and the radial direction refrigerant flow path, a guide portion for guiding the refrigerant from the axial direction refrigerant flow path to the radial direction refrigerant flow path is provided.
The rotating electrical machine according to claim 10.

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