Rotor of rotating electric machine and rotating electric machine

1. A rotor of a rotating electric machine, wherein at least one cutout groove is provided in a rotor stepped portion, in an axis of rotation direction of the rotor stepped portion, in such a way that a flexural rigidity around an in-polar axis is adjusted, and a flexural rigidity around an interpolar axis and the flexural rigidity around the in-polar axis have asymmetry.

2. The rotor of the rotating electric machine according to claim 1 , wherein at least one set of a multiple of the cutout groove whose sectional forms are identical is provided in outer diameter positions on the interpolar axis of the rotor stepped portion, in one portion or over an overall length of the rotor stepped portion with respect to the axis of rotation direction.

3. The rotor of the rotating electric machine according to claim 1 , wherein at least one set of a multiple of the cutout groove whose sectional forms differ is provided in outer diameter positions on the interpolar axis of the rotor stepped portion, in one portion or over an overall length of the rotor stepped portion with respect to the axis of rotation direction.

4. The rotor of the rotating electric machine according to claim 1 , wherein at least one cutout groove whose sectional form is tapered is provided in an outer diameter position on the interpolar axis of the rotor stepped portion, in one portion or over an overall length of the rotor stepped portion with respect to the axis of rotation direction.

5. The rotor of the rotating electric machine according to claim 1 , wherein at least one set of a multiple of the cutout groove whose sectional forms are identical is provided in an angular range of 0 to 45 degrees in the in-polar axis direction, with the interpolar axis as a center, in one portion or over an overall length of the rotor stepped portion with respect to the axis of rotation direction.

6. The rotor the rotating electric machine according to claim 1 , wherein at least one set of a multiple of the cutout groove whose sectional forms differ is provided in outer diameter positions in the rotor stepped portion, in an angular range of 0 to 45 degrees in the in-polar axis direction, with the interpolar axis as a center, in one portion or over an overall length of the rotor stepped portion with respect to the axis of rotation direction.

7. The rotor of the rotating electric machine according to claim 1 , wherein at least one set of a multiple of the cutout groove whose sectional forms are tapered is provided in outer diameter positions in the rotor stepped portion, in an angular range of 0 to 45 degrees in the in-polar axis direction, with the interpolar axis as a center, in one portion or over an overall length of the rotor stepped portion with respect to the axis of rotation direction.

8. The rotor of the rotating electric machine according to claim 2 , wherein double frequency vibration in a whole region of driving rotational speed is restricted by the flexural rigidity around the in-polar axis of the rotor stepped portion being adjusted using the cutout groove.

9. The rotor of the rotating electric machine according to claim 3 , wherein double frequency vibration in a whole region of driving rotational speed is restricted by the flexural rigidity around the in-polar axis of the rotor stepped portion being adjusted using the cutout groove.

10. The rotor the rotating electric machine according to claim 4 , wherein double frequency vibration in a whole region of driving rotational speed is restricted by the flexural rigidity around the in-polar axis of the rotor stepped portion being adjusted using the cutout groove.

11. The rotor of the rotating electric machine according to claim 5 , wherein double frequency vibration in a whole region of driving rotational speed is restricted by the flexural rigidity around the in-polar axis of the rotor stepped portion being adjusted using the cutout groove.

12. The rotor of the rotating electric machine according to claim 6 , wherein double frequency vibration in a whole region of driving rotational speed is restricted by the flexural rigidity around the in-polar axis of the rotor stepped portion being adjusted using the cutout groove.

13. The rotor of the rotating electric machine according to claim 7 , wherein double frequency vibration in a whole region of driving rotational speed is restricted by the flexural rigidity around the in-polar axis of the rotor stepped portion being adjusted using the cutout groove.

14. The rotor of the rotating electric machine according to claim 8 , wherein an asymmetry ratio of flexural rigidity around the in-polar axis with respect to flexural rigidity around the interpolar axis of a rotor main portion is −6 to −1% when there is resonance in a primary flexural vibration mode of double frequency vibration and 1 to 6% when there is resonance in a tertiary flexural vibration mode, and an asymmetry ratio of flexural rigidity around the in-polar axis with respect to flexural rigidity around the interpolar axis of the rotor stepped portion is 1 to 6%.

15. The rotor of the rotating electric machine according to claim 9 , wherein an asymmetry ratio of flexural rigidity around the in-polar axis with respect to flexural rigidity around the interpolar axis of a rotor main portion is −6 to '11% when there is resonance in a primary flexural vibration mode of double frequency vibration and 1 to 6% when there is resonance in a tertiary flexural vibration mode, and an asymmetry ratio of flexural rigidity around the in-polar axis with respect to flexural rigidity around the interpolar axis of the rotor stepped portion is 1 to 6%.

16. The rotor of the rotating electric machine according to claim 10 , wherein an asymmetry ratio of flexural rigidity around the in-polar axis with respect to flexural rigidity around the interpolar axis of a rotor main portion is −6 to −1% when there is resonance in a primary flexural vibration mode of double frequency vibration and 1 to 6% when there is resonance in a tertiary flexural vibration mode, and an asymmetry ratio of flexural rigidity around the in-polar axis with respect to flexural rigidity around the interpolar axis of the rotor stepped portion is 1 to 6%.

17. The rotor of the rotating electric machine according to claim 11 , wherein an asymmetry ratio of flexural rigidity around the in-polar axis with respect to flexural rigidity around the interpolar axis of a rotor main portion is −6 to −1% when there is resonance in a primary flexural vibration mode of double frequency vibration and 1 to 6% when there is resonance in a tertiary flexural vibration mode, and an asymmetry ratio of flexural rigidity around the in-polar axis with respect to flexural rigidity around the interpolar axis of the rotor stepped portion is 1 to 6%.

18. The rotor of the rotating electric machine according to claim 12 , wherein an asymmetry ratio of flexural rigidity around the in-polar axis with respect to flexural rigidity around the interpolar axis of a rotor main portion is −6 to −1% when there is resonance in a primary flexural vibration mode of double frequency vibration and 1 to 6% when there is resonance in a tertiary flexural vibration mode, and an asymmetry ratio of flexural rigidity around the in-polar axis with respect to flexural rigidity around the interpolar axis of the rotor stepped portion is 1 to 6%.

19. The rotor of the rotating electric machine according to claim 13 , wherein an asymmetry ratio of flexural rigidity around the in-polar axis with respect to flexural rigidity around the interpolar axis of a rotor main portion is −6 to −1% when there is resonance in a primary flexural vibration mode of double frequency vibration and 1 to 6% when there is resonance in a tertiary flexural vibration mode, and an asymmetry ratio of flexural rigidity around the in-polar axis with respect to flexural rigidity around the interpolar axis of the rotor stepped portion is 1 to 6%.

20. The rotor of the rotating electric machine according to claim 14 , wherein vibration in a secondary flexural vibration mode of double frequency vibration is restricted owing to the asymmetry ratio of flexural rigidity around the in-polar axis with respect to flexural rigidity around the interpolar axis of the rotor stepped portion being 1 to 6%.

21. The rotor of the rotating electric machine according to claim 15 , wherein vibration in a secondary flexural vibration mode of double frequency vibration is restricted owing to the asymmetry ratio of flexural rigidity around the in-polar axis with respect to flexural rigidity around the interpolar axis of the rotor stepped portion being 1 to 6%.

22. The rotor of the rotating electric machine according to claim 16 , wherein vibration in a secondary flexural vibration mode of double frequency vibration is restricted owing to the asymmetry ratio of flexural rigidity around the in-polar axis with respect to flexural rigidity around the interpolar axis of the rotor stepped portion being 1 to 6%.

23. The rotor of the rotating electric machine rotor according to claim 17 , wherein vibration in a secondary flexural vibration mode of double frequency vibration is restricted owing to the asymmetry ratio of flexural rigidity around the in-polar axis with respect to flexural rigidity around the interpolar axis of the rotor stepped portion being 1 to 6%.

24. The rotor of the rotating electric machine according to claim 18 , wherein vibration in a secondary flexural vibration mode of double frequency vibration is restricted owing to the asymmetry ratio of flexural rigidity around the in-polar axis with respect to flexural rigidity around the interpolar axis of the rotor stepped portion being 1 to 6%.

25. The rotor of the rotating electric machine according to claim 19 , wherein vibration in a secondary flexural vibration mode of double frequency vibration is restricted owing to the asymmetry ratio of flexural rigidity around the in-polar axis with respect to flexural rigidity around the interpolar axis of the rotor stepped portion being 1 to 6%.

26. A rotating electric machine comprising the rotor according to claim 1 .