JP4283081B2 - Rotating electrical machine rotor - Google Patents

Description

  According to the present invention, a permanent magnet is held in a plurality of circumferentially elongated slots formed along the outer periphery of the rotor core, and the outer peripheral portion and the diameter are provided between adjacent slots and are radially outer than the slots of the rotor core. The present invention relates to a rotor of a rotating electrical machine that supports a centrifugal force acting on a permanent magnet as a rotor core rotates by a bridge portion that connects an inner peripheral portion on the inner side in the direction.

  By arranging eight field permanent magnets 10A and 10B in a square shape along the outer periphery of the rotor core 3 on one side, and opening a through hole 9 in the bridge portion corresponding to the apex of the square, A rotor of an electric motor in which a pair of thin portions 8 are formed between a punched hole and the rotor slots 5A and 5B on both sides thereof is known from Patent Document 1 below.

In addition, a rotor 14 of a rotating electrical machine in which a flux barrier hole 4 in which a permanent magnet embedded hole 18 is extended in the circumferential direction is formed in a bridge 11 sandwiched between permanent magnets 2 arranged along the outer periphery of the rotor core 3 is provided. It is known from Patent Document 2 below.
JP 2002-354726 A JP 2003-61283 A

  By the way, in a rotor in which a permanent magnet is embedded in a slot formed on the outer periphery of the rotor core, when a large centrifugal force acts on the permanent magnet during high-speed rotation of the rotor, stress concentrates on the starting point of the corner of the slot, and cracks form from that portion. May occur and reduce the durability of the rotor.

  In the above-mentioned Patent Document 1, since eight field permanent magnets 10A and 10B are arranged in a square shape, two on each side, rotor slots 5A and 5B corresponding to the apexes of the squares. The thickness between the end of the rotor core 3 and the outer periphery of the rotor core 3 is locally reduced to reduce the strength, and the field permanent magnets 10A and 10B are fitted into the rotor slots 5A and 5B without any gaps. Therefore, when the rotor core 3 rotates at high speed, the centrifugal force acting on the field permanent magnets 10A and 10B acts directly on the corners of the rotor slots 5A and 5B, and stress concentrates on those portions to further generate cracks. There is a problem that makes it easier to do.

  Moreover, since the thing described in the said patent document 2 has the flux barrier hole 4 which extended the permanent magnet embedding hole 18 to the circumferential direction, the centrifugal force which acts on the permanent magnet 2 is a permanent magnet embedding hole. 18 is prevented from acting directly on the corners, but the thin bridge 11 sandwiched between the two flux barrier holes 4 facing each other extends in the radial direction of the rotor. Only the tensile load acts on the bridge 11 by the force, and the bending load does not act. As a result, the rigidity of the bridge 11 becomes high and elastic deformation in the radial direction becomes difficult. Therefore, it is difficult to sufficiently reduce the stress concentration of the permanent magnet embedded hole 18 with which the corner portion of the permanent magnet 2 abuts. It was.

  The present invention has been made in view of the above circumstances, and an object thereof is to reduce stress concentration due to centrifugal force to a plurality of slots formed along the outer periphery of a rotor core and holding a permanent magnet as much as possible.

In order to achieve the above object, according to the first aspect of the present invention, a permanent magnet is held inside a plurality of circumferentially elongated slots formed along the outer periphery of the rotor core, and between adjacent slots. A rotor of a rotating electrical machine that supports a centrifugal force that acts on a permanent magnet as the rotor core rotates by means of a bridge portion that is provided and connects an outer peripheral portion radially outer than a slot of the rotor core and an inner peripheral portion radially inner. Each of the bridge portions includes a rib formed between a plurality of spaces formed at a circumferential end of the slot so that both ends thereof are connected to the outer peripheral portion and the inner peripheral portion. of the intermediate portion, the rotor of the rotary electric machine according to at least one of said Rukoto bent portion is formed to allow the said ribs are elastically bent and deformed radially outward by the centrifugal force.
Is proposed.

According to the second aspect of the present invention, in addition to the configuration of the first aspect, the rib is formed by alternately connecting the portions extending in the radial direction and the portions extending in the circumferential direction by the bent portions. A rotor of a rotating electrical machine characterized by being configured as described above is proposed.

According to the invention described in claim 3, in addition to the configuration of claim 1, the rib has portions inclined with respect to the radial direction and the circumferential direction on both sides of the bent portion. A rotor of a rotating electric machine is proposed.

According to the configuration of the first aspect, the bridge portion formed between the plurality of slots formed along the outer periphery of the rotor core and holding the permanent magnet therein is connected to the outer peripheral portion and the inner peripheral portion of the rotor core at both ends. And at least one bent portion that allows the rib to be elastically bent and deformed radially outward by a centrifugal force acting on the permanent magnet. Therefore, the load due to the centrifugal force is absorbed by the elastic bending deformation at the bent portion of the rib, so that the stress concentration generated at the starting point of the corner portion of the slot can be alleviated and the durability of the rotor core can be improved. In addition, since the plurality of spaces formed at the circumferential ends of the slots are arranged so as to surround the ribs, this space can more effectively relieve the stress concentration generated at the starting point of the corners of the slots. it can.

According to the second aspect of the present invention, the ribs are formed by alternately connecting the portions extending in the generally radial direction and the portions extending in the generally circumferential direction at the bent portions, so that the ribs are formed by the centrifugal force acting on the permanent magnet. It is possible to efficiently bend and deform elastically and to relieve the occurrence of strong stress concentration at the starting point of the corner of the slot.

According to the configuration of the third aspect, since the rib has the inclined portions with respect to the radial direction and the circumferential direction on both sides of the bent portion, the rib is efficiently elastically bent and deformed by the centrifugal force acting on the permanent magnet. It is possible to alleviate the occurrence of strong stress concentration at the starting point of the corner of the slot.

  DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described below based on examples of the present invention shown in the accompanying drawings.

  1 to 3 show a first embodiment of the present invention. FIG. 1 is a longitudinal sectional view of a rotor, FIG. 2 is a sectional view taken along line 2-2 of FIG. 1, and FIG. It is.

  As shown in FIGS. 1 and 2, a rotor 11 that is rotatably arranged around an axis L inside a stator of a motor includes a rotor shaft 12, a rotor core 13, a plurality of permanent magnets 14, and a first end. The plate 15, the second end plate 16, the first collar 17, and the second collar 18 are configured. The rotor core 13 is obtained by laminating a plurality of punched electromagnetic steel plates and integrating them by caulking, and is spline-fitted to the outer periphery of the rotor shaft 12 so as not to be relatively rotatable. A first end plate 15 fitted to the outer periphery of the rotor shaft 12 and abutting against one end surface of the rotor core 13 is fixed with a first collar 17 press-fitted into the outer periphery of the rotor shaft 12, and fitted to the outer periphery of the rotor shaft 12. Then, the second end plate 16 that contacts the other end surface of the rotor core 13 is fixed by the second collar 18 that is press-fitted into the outer periphery of the rotor shaft 12, so that the rotor core is sandwiched between the first and second end plates 15 and 16. 13 is positioned in the direction of the axis L.

  Ten slots 20 elongated in the circumferential direction are formed at equal intervals along the outer periphery of the rotor core 13, and twelve permanent magnets 14 are held in each slot 20. The periphery of each slot 20 is surrounded by an outer peripheral portion 13a, an inner peripheral portion 13b, and a pair of bridge portions 21 and 21. The outer peripheral portion 13 a is a thin portion sandwiched between the outer peripheral surface of the rotor core 13 and the radially outer end surface of the slot 20, and the inner peripheral portion 13 b is a portion radially inward from the radially inner end surface of the slot 20. The bridge portion 21 is a portion sandwiched between adjacent slots 20, 20, and when a centrifugal force acts on the permanent magnets 14 in the slot 20 by the rotation of the rotor 11, the centrifugal force is circular from the outer peripheral portion 13 a of the rotor core 13. It is transmitted to the inner peripheral part 13b through the bridge parts 21 and 21 on both sides in the circumferential direction.

As apparent from FIG. 3, the bridge portion 21 of the rotor core 13 has two spaces 20a and 20b extending from the radially outer end and the radially inner end of the right slot 20 to the left side in the circumferential direction, and the left side thereof. A space 20c extending from the radially outer end of the slot 20 to the right in the circumferential direction is formed, and the ribs 23 are formed by these spaces 20a, 20b, and 20c. The rib 23 includes a first portion 23a that extends substantially radially inward from the outer peripheral portion 13a of the rotor core 13, a second portion 23b that extends generally leftward from the radial inner end of the first portion 23a, and a second portion 23b. A third portion 23c extending substantially radially inward from the left end of the rotor core and continuing to the inner peripheral portion 13b of the rotor core 13 to form a crank shape, between the first portion 23a and the second portion 23b, and the second portion A bent portion is formed between 23b and the third portion 23c to allow the rib 23 to be elastically bent and deformed radially outward .

When the rotor 11 rotates at high speed and centrifugal force acts on each permanent magnet 14, a radially outward load acts on the outer peripheral portion 13 a of the slot 20 located on the radially outer side of the permanent magnet 14. Therefore, the stress concentration portions a and a which are the starting points of the corners of the slot 20 (the points where the corner R starts) serve as fulcrums for the bending load acting on the outer peripheral portion 13a of the slot 20, and strong stress is applied to the stress concentration portions a and a May concentrate and the rotor core 13 may be damaged. However, in this embodiment, the bridge portion 21 sandwiched between the two slots 20 and 20 is provided with a rib 23 having a crank-like bent portion surrounded by the three spaces 20a, 20b, and 20c. The second portion 23b extending in the circumferential direction of the rib 23 easily elastically deforms and elastically bends and deforms the rib 23 radially outward, so that the stress concentration on the stress concentration portions a and a of the slot 20 is greatly increased. The rotor core 13 is prevented from being damaged by being relaxed. Moreover, since the spaces 20a and 20c are formed at the circumferential ends of the slot 20, the radius of curvature of the corner R portion of the slot 20 starting from the stress concentration portions a and a is increased to further effectively concentrate the stress. Can be relaxed.

By the way, the shape of the rib 23 in which the portion extending in the generally circumferential direction and the portion extending in the generally radial direction are connected with the bent portion interposed therebetween is not limited to the crank shape of the first embodiment, and other embodiments are conceivable. The second embodiment shown in FIG. 4 and the third embodiment shown in FIG. 5 include a space 20a on one side of a pair of slots 20 and 20 facing each other across the bridge portion 21, and spaces 20b and 20c on the other side. From the outer periphery 13a of the rotor core 13, a first portion 23a extending generally radially inward, a second portion 23b extending generally circumferentially left from the radially inner end of the first portion 23a, and a left end of the second portion 23b A third portion 23c extending generally radially inward, a fourth portion 23d extending generally rightward from the radially inner end of the third portion 23c, and a rotor core extending generally radially inward from the right end of the fourth portion 23d. 13, and a third portion 23 c between the first portion 23 a and the second portion 23 b, between the second portion 23 b and the third portion 23 c, and the third portion 23 c. And the fourth part 23 Each bending portion to allow the bending elastic ribs 23 radially outward deformation is formed between the between, and a fourth portion 23d and the fifth portion 23e of the.

The second of these, according to the third embodiment, to facilitate to further elastically deformed further reduce the rigidity of the ribs 23 as compared with the first embodiment, the stress concentration portion a of the slot 20, the stress concentration of a Can be mitigated more effectively.

Next, a reference example of the present invention will be described with reference to FIG.

In the reference example of FIG. 6, a rib 23 composed of a first portion 24 f inclined with respect to both the circumferential direction and the radial direction is formed between the space 20 a of the right slot 20 and the space 20 b of the left slot 20. that has been.

Next, a fourth embodiment and a fifth embodiment of the present invention will be described with reference to FIGS.

In the fourth embodiment of FIG. 7, the first portion inclined between both the circumferential direction and the radial direction between the two spaces 20a, 20b of the right slot 20 and the space 20c of the left slot 20 is provided. Brighter Bed 23 such than 23f and second portion 23g is being formed, between the first portion 23f and second portion 23g, to allow for elastic bending deformation rib 23 is radially outward "V "-shaped bent portions that are formed. According to the fourth embodiment, the rib 23 can be more easily deformed radially outward by absorbing the load caused by the centrifugal force with the "<"-shaped bent portion .

In the fifth embodiment of FIG. 8, the space 20a, 20b in the right slot 20, the two spaces 20c, 20d in the left slot 20, and the space 20e separated from both slots 20, 20 are used. In addition, ribs 23 formed of a first portion 23f to a fourth portion 23i that are inclined with respect to both the circumferential direction and the radial direction are formed , and between the first portion 23a and the second portion 23b, and the third portion each portion 23h and between the fourth portion 23i, that make up the diamond-shaped bent portion as a whole is formed bent portion to allow the ribs 23 to bend elastically radially outward deformation. According to the fifth embodiment, the rib 23 can be more easily deformed radially outward by absorbing the load caused by the centrifugal force by the rhombic bent portion .

  As mentioned above, although the Example of this invention was explained in full detail, this invention can perform a various design change in the range which does not deviate from the summary.

  For example, in the embodiment, the rotor 11 of the motor is illustrated, but the present invention can also be applied to the rotor of the generator.

Longitudinal section of the rotor 2-2 sectional view of FIG. Part 3 enlarged view of FIG. The figure which shows the shape of the rib of 2nd Example The figure which shows the shape of the rib of 3rd Example The figure which shows the shape of the rib of a reference example The figure which shows the shape of the rib of 4th Example The figure which shows the shape of the rib of 5th Example

13 rotor core 13a outer peripheral part 13b inner peripheral part 14 permanent magnet 20 slot 20a-20d space 21 bridge part 23 ribs 23a, 23c, 23e parts 23b, 23d extending in a generally radial direction parts 23f-23i extending in a generally circumferential direction Inclined part with respect to the circumferential direction

Claims (3)

A permanent magnet (14) is held in a plurality of circumferentially elongated slots (20) formed along the outer periphery of the rotor core (13), and is provided between adjacent slots (20). The bridge portion (21) that connects the outer peripheral portion (13a) radially outward from the slot (20) and the inner peripheral portion (13b) radially inner is provided with the permanent magnet (14) as the rotor core (13) rotates. In the rotor of the rotating electrical machine that supports the centrifugal force acting on
Each bridge portion (21) is sandwiched between a plurality of spaces (20a to 20d) formed at the circumferential end of the slot (20), and both ends thereof are the outer peripheral portion (13a) and the inner peripheral portion (13b). A rib (23) formed so as to be continuous with the rib (23), and at least an intermediate portion of the rib (23) is allowed to be elastically bent and deformed radially outward by the centrifugal force. the rotor of a rotary electric machine characterized by Rukoto one bend is formed. The rib (23) is configured by alternately connecting portions (23a, 23c, 23e) extending in a generally radial direction and portions (23b, 23d) extending in a generally circumferential direction at the bent portion. The rotor of the rotating electrical machine according to claim 1. The rotor of a rotating electrical machine according to claim 1, wherein the rib (23) has portions (23f to 23i) inclined with respect to a radial direction and a circumferential direction on both sides of the bent portion .

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