RESILIENT ISOLATION MEMBERS AND RELATED METHODS OF REDUCING ACOUSTIC NOISE AND/OR STRUCTURAL VIBRATION IN AN ELECTRIC MACHINE

• US 20060255666A1
• Filed: 05/12/2005
• Published: 11/16/2006
• Est. Priority Date: 05/12/2005
• Status: Active Grant

• Current Assignee: Nidec S R Drives Ltd (Nidec Corporation)
• Original Assignee: Emerson Electric Company
• Inventors: Modi, Chetan O., Horst, Gary E., Williams, Donald J., McClelland, Michael L.
• Granted Patent: US 7,196,438 B2
• Time in Patent Office: Days
• US Class Current: 310/51
• CPC Class Codes: H02K 5/15 Mounting arrangements for bearing-shields or end plates
• CPC Class Codes: H02K 5/24 specially adapted for suppression or reduction of noise or vibrations

Abstract

A resilient isolation member is configured for use with an electric machine having a housing, a stator within the housing, and an end shield. The resilient isolation member includes first and second end portions, a sidewall extending between the first and second end portions, and a lip is disposed along an outer surface of the sidewall. The resilient isolation member is sized for mounting between the end shield and the stator, with the first and second end portions respectively abutting against a first inner portion of the end shield and a portion of the stator and with the lip abutting against a second inner portion of the end shield and a portion of the housing.

Claims

1. A resilient isolation member for an electric machine having a housing, a stator within the housing, and an end shield, the resilient isolation member comprising a first end portion, a second end portion, a sidewall extending between the first and second end portions, and a lip disposed along an outer surface of the sidewall, the resilient isolation member being sized for mounting between the end shield and the stator, with the first and second end portions respectively abutting against a first inner portion of the end shield and a portion of the stator and with the lip abutting against a second inner portion of the end shield and a portion of the housing.

2. The resilient isolation member of claim 1, wherein the sidewall defines a generally annular shape having a central opening.

3. The resilient isolation member of claim 1, further comprising a portion downwardly depending from the lip and configured to be disposed between a surface of the housing and a surface of the end shield for maintaining a radial clearance between the surface of the end shield and the surface of the housing.

4. The resilient isolation member of claim 1, further comprising at least one notch configured to engage at least one rib defined by the end shield such that the engagement of the notch with the rib inhibits relative rotational movement between the resilient isolation member and the end shield.

5. The resilient isolation member of claim 1, further comprising at least one tab configured to engage at least one opening defined by the housing of the electric machine such that the engagement of the tab with the opening inhibits relative rotational movement between the resilient isolation member and the housing.

6. An electric machine comprising a housing including an end portion, a stator within the housing, an end shield, and at least one resilient isolation member providing resilient mounting between the end shield and the stator, the resilient isolation member including a first end portion abutting against a first inner portion of the end shield, a second end portion abutting against a portion of the stator, a sidewall extending between the first and second end portions, a lip disposed along an outer surface of the sidewall, the lip abutting against a second inner portion of the end shield and a portion of the housing.

7. The machine of claim 6, wherein the end shield is a front end shield, and wherein the machine further comprises a rear end shield coupled to the front end shield with at least one mechanical fastener received within at least one fastener hole defined by the front end shield, and at least one resilient bushing including at least a portion disposed between at least a portion of the mechanical fastener and at least a portion of a sidewall defining at least a portion of the fastener hole.

8. The machine of claim 7, further comprising at least one resilient mount for resiliently mounting the rear end shield to external supporting structure.

9. The machine of claim 8, wherein the resilient mount includes at least one resilient grommet engaged with an opening defined by a mounting arm of the rear end shield.

10. The machine of claim 8, wherein the rear end shield is resiliently mounted to external supporting structure with the resilient mount, and wherein the front end shield is hard-mounted to external supporting structure.

11. The machine of claim 6, further comprising at least one O-ring disposed within the end shield between a surface of the housing and a surface of the end shield for maintaining a radial clearance between the surface of the end shield and the surface of the housing.

12. The machine of claim 6, wherein the resilient isolation member includes a portion downwardly depending from the lip and configured to be disposed between a surface of the housing and a surface of the end shield for maintaining a radial clearance between the surface of the end shield and the surface of the housing.

13. The machine of claim 6, wherein the housing comprises a liquid cooling jacket.

14. The machine of claim 6, wherein the end shield is a front end shield, and wherein the machine further comprises a rear end shield coupled to the front end shield, and at least one resilient mount for resiliently mounting the rear end shield to external supporting structure.

15. The machine of claim 14, wherein the resilient mount includes at least one resilient grommet engaged with an opening defined by a mounting arm of the rear end shield.

16. A method of assembling an electric machine having a housing, a stator within the housing, and an end shield, the method comprising positioning at least one resilient isolation member between the end shield and the stator such that first and second end portions of the resilient isolation member respectively abut against a first inner portion of the end shield and a portion of the stator and such that a peripheral lip of the resilient isolation member abuts against a second inner portion of the end shield and a portion of the housing.

17. The method of claim 16, wherein the end shield is a front end shield, and wherein the method further comprises resiliently coupling a rear end shield to the front end shield such that the stator is generally between the front and rear end shields.

18. The method of claim 17, wherein resiliently coupling the rear end shield to the front end shield includes positioning at least one resilient bushing such that at least a portion thereof is between a sidewall defining a fastener hole and a mechanical fastener positioned within the fastener hole.

19. The method of claim 16, wherein the end shield is a front end shield, and wherein the method further comprises resiliently mounting a rear end shield of the electric machine to external supporting structure.

20. The method of claim 19, wherein resiliently mounting the rear end shield to external supporting structure includes engaging a resilient grommet with an opening defined by at least one mounting arm of the rear end shield such that at least a portion of the resilient grommet is between the mounting arm and a mechanical fastener positioned within the opening.

21. The method of claim 16, wherein positioning the resilient isolation member includes positioning a portion downwardly depending from the peripheral lip between a surface of the housing and a surface of the end shield for maintaining a radial clearance between the surface of the end shield and the surface of the housing.

22. The method of claim 16, wherein the method includes engaging at least one notch defined by the resilient isolation member with at least one rib defined by the end shield to inhibit relative rotational movement between the resilient isolation member and the end shield.

23. The method of claim 16, wherein the method includes engaging at least one tab defined by the resilient isolation member with at least one opening defined by the housing of the electric machine to inhibit relative rotational movement between the resilient isolation member and the housing.

24. The method of claim 16, further positioning at least one O-ring within the end shield between a surface of the end shield and a surface of the housing of the electric machine for maintaining a radial clearance between the surface of the end shield and the surface of the housing.

25. A method of assembling an electric machine having a stator, a front end shield, and a rear end shield, the method comprising positioning at least one resilient isolation member between the front end shield and the stator, resiliently coupling the rear end shield to the front end shield such that the stator is generally between the front and rear end shields, resiliently mounting the rear end shield to external supporting structure, and hard-mounting the front end shield to external supporting structure.

26. The method of claim 25, wherein resiliently coupling the rear end shield to the front end shield includes positioning at least one resilient bushing such that at least a portion thereof is between a sidewall defining a fastener hole and a mechanical fastener positioned within the fastener hole, and wherein resiliently mounting the rear end shield to external supporting structure includes engaging a resilient grommet with an opening defined by at least one mounting arm of the rear end shield such that at least a portion of the resilient grommet is between the mounting arm and a mechanical fastener positioned within the opening.

27. The method of claim 26, wherein positioning the resilient isolation member includes positioning first and second end portions of the resilient isolation member between a first inner portion of the front end shield and a portion of the stator, and positioning a peripheral lip of the resilient isolation member between a second inner portion of the front end shield and a portion of a housing of the electric machine.