IP Library › Granted Patent US 10,211,688
Granted Patent B2
US 10,211,688 · App. 14/889,969 · Granted Feb 19, 2019

Electric machine

Inventors: Natsuki Watanabe (Hiratsuka, JP); Teiichirou Chiba (Hiratsuka, JP); Yasuhiko Matsuki (Fujisawa, JP)
Assignee: Komatsu Ltd.
H02K1/2706H02K1/2766H02K1/32H02K9/19H02K21/046H02K5/20
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Quick Facts
Patent No.
US 10,211,688
App. No.
14/889,969
Granted
Feb 19, 2019
Kind
B2
Abstract

A motor includes: an annular stator attached in a housing; a rotor that is disposed in the stator and is rotatably supported by the housing; and a plurality of permanent magnets embedded in a rotor core of the rotor, in which the rotor core has embedding holes respectively in which the permanent magnets are fitted, and each of the embedding holes is formed with filling holes each continuous in an axial direction of the rotor core at diagonal positions of each of the permanent magnets.

Claims (47)

1. A motor comprising:

an annular stator attached in a housing;

a rotor that is disposed in the stator and is rotatably supported by the housing; and

a plurality of permanent magnets embedded in a rotor core of the rotor, wherein the rotor core defines embedding holes in which the permanent magnets are respectively fitted,

each of the embedding holes forms filling holes that are configured to be filled with an adhesive, the filling holes extending continuously in an axial direction of the rotor core at diagonal positions of each of the permanent magnets, and

the rotor core further comprises a flux barrier, the flux barrier being in a form of an empty space that is defined by each of the embedding holes.

2. The motor according to claim 1 , wherein

the flux barrier is defined by an end of each of the embedding holes, and

the flux barrier defines an oil path through which a cooling oil flows.

3. The motor according to claim 1 , wherein

the flux barrier is defined by an end of each of the embedding holes, and

the flux barrier defines a support that supports each of the permanent magnets, the support projecting toward each of the diagonal positions of each of the permanent magnets.

4. The motor according to claim 3 , wherein

the support is opposite the filling hole across a corner of each of the permanent magnets in a form of a prism.

5. The motor according to claim 1 , wherein

the filling holes are filled with an adhesive that fixes each of the permanent magnets to the rotor core.

6. The motor according to claim 1 , wherein

the adhesive comprises a resin material.

7. The motor according to claim 1 , wherein

each of the filling holes abuts a lateral surface on a long side of each of the permanent magnets.

8. The motor according to claim 1 , wherein

the flux barrier faces a portion of a short side of each of the permanent magnets and a portion of a long side of each of the permanent magnets.

9. The motor according to claim 1 , wherein,

the rotor core comprises supports respectively provided at positions opposing short sides of each of the permanent magnets fitted in the respective embedding holes, the supports being in contact with the short sides of each of the permanent magnets.

10. The motor according to claim 9 , wherein

each support contacts one of the short sides of each of the permanent magnets, and divides the corresponding embedding hole into the filling hole and the flux barrier.

11. The motor according to claim 9 , wherein

each support is positioned between the flux barrier and the filling hole of each of the permanent magnets fitted in the respective embedding holes.

12. A motor comprising:

an annular stator attached in a housing;

a rotor that is disposed in the stator and is rotatably supported by the housing; and

a plurality of cross-sectionally rectangular permanent magnets embedded in a rotor core of the rotor, wherein

a pair of ones of the permanent magnets, which are disposed in a V-shape seen from an axial center of the rotor, define one magnetic pole,

the rotor core comprises:

embedding holes respectively in which the permanent magnets are fitted;

an outer-circumferential flux barrier that is defined by a first end of each of the embedding holes and is positioned near an outer circumference of the rotor core; and

an inner flux barrier that is defined by a second end of each of the embedding holes and is positioned on an inner side of each of the embedding holes than the outer-circumferential flux barrier,

each of the embedding holes is formed with filling holes, which are each continuous in an axial direction of the rotor core, at diagonal positions of each of the permanent magnets,

the inner flux barrier defines an oil path through which a cooling oil flows,

the outer-circumferential flux barrier and the inner flux barrier each comprise a support that supports each of the permanent magnets by contact with a part of an end surface of each of the permanent magnets, and

the support is opposite the filling hole across a corner of each of the permanent magnets in a form of a prism.

13. The motor according to claim 12 , wherein

the filling holes are filled with an adhesive that fixes each of the permanent magnets to the rotor core.

14. The motor according to claim 13 , wherein

the adhesive comprises a resin material.

15. The motor according to claim 12 , wherein

each of the filling holes abuts a lateral surface on a long side of each of the permanent magnets.

Assignments (1)
ASSIGNMENT OF ASSIGNOR'S INTEREST Recorded Nov 10, 2015
From: WATANABE, NATSUKI; CHIBA, TEIICHIROU; MATSUKI, YASUHIKO
To: KOMATSU LTD.
Reel/Frame 037003/0543 →
Continuity (1)
Related Publication 20160301268A1 · Oct 13, 2016