System and method for monitoring the status of one or more components of an electrical machine

Patent metadata

Field	Value
Publication number	US-11355991-B2
Application number	US-201916592363-A
Country	US
Kind code	B2
Filing date	Oct 3, 2019
Priority date	Oct 4, 2018
Publication date	Jun 7, 2022
Grant date	Jun 7, 2022

Abstract

Example brush holder assemblies of an electric machine are disclosed. An example brush holder assembly of an electric machine includes a carbon brush including an upper surface and a lower surface opposite the upper surface. The brush holder assembly also includes one or more lead wires extending out of the carbon brush at an insertion point on the upper surface and a first cavity extending into the carbon brush from the upper surface at a location spaced away from the insertion point of the one or more lead wires and unobstructed by the one or more lead wires.

First claim

What is claimed is:

1. An assembly for a brush holder assembly of an electric machine, comprising:
a carbon brush including an upper surface and a lower surface opposite the upper surface,
one or more lead wires extending out of the carbon brush at an insertion point on the upper surface;
a first cavity extending into the carbon brush from the upper surface at a location spaced away from the insertion point of the one or more lead wires and unobstructed by the one or more lead wires; and
a spacer coupled to the carbon brush, the spacer including a first projection configured to releasably engage within the first cavity.

2. The assembly of claim 1 , further comprising a wear state monitor coupled to the spacer, wherein the wear state monitor is designed to measure an angular displacement of the wear state monitor as the wear state monitor rotates.

3. The assembly of claim 2 , wherein the brush further includes a length measured from the upper surface to the lower surface, wherein the length is diminished from an initial length as the lower surface of the carbon brush wears away during use and wherein the measured angular displacement of the wear state monitor correlates to the diminished length of the carbon brush.

4. The assembly of claim 1 , wherein engagement of the first projection in the first cavity of the carbon brush is configured to retain the spacer in a fixed relationship with the carbon brush.

5. The assembly of claim 4 , wherein the first projection extends away from a bottom surface of the spacer.

6. The assembly of claim 5 , wherein the first cavity includes a channel extending along the upper surface of the carbon brush, and wherein the first projection is configured to mate with and insert into the channel.

7. The assembly of claim 6 , wherein the first cavity includes a first tapered surface, and wherein the first projection includes a second tapered surface designed to mate with the first tapered surface of the first cavity.

8. The assembly of claim 1 , wherein the carbon brush further comprises a second cavity extending into the carbon brush from the upper surface at a location spaced away from the insertion point of the one or more lead wires and unobstructed by the one or more lead wires, wherein the second cavity is spaced away from the first cavity.

9. The assembly of claim 8 , wherein the spacer further comprises a second projection configured to releasably engage within the second cavity.

10. The assembly of claim 9 , wherein the first projection and the second projection are designed to engage the carbon brush simultaneously, and wherein the engagement of the first projection and the second projection with the first and second cavities of the carbon brush is configured to retain the spacer in a fixed relationship with the carbon brush.

11. The assembly of claim 10 , wherein both the first projection and the second projection extend away from a bottom surface of the spacer.

12. The assembly of claim 11 , wherein the shape of both the first projection and the second projection is designed to mate with the first cavity and the second cavity.

13. A system for monitoring the wear state of a carbon brush, comprising:
a brush holder assembly, the brush holder assembly including:
a carbon brush including an upper surface, a lower surface opposite the upper surface, and a length measured from the upper surface to the lower surface, wherein the length is diminished from an initial length as the lower surface of the carbon brush wears away during use;
a spring having a first end and a second end, and a coiled portion;
a wear state monitor positioned within the coiled portion of the spring, the wear state monitor including a sensor, wherein the sensor is configured to measure an angular displacement of the wear state monitor as the wear state monitor rotates;
a spacer positioned between the coiled portion of the spring and the upper surface of the carbon brush, the spacer including a first projection extending away from a bottom surface of the spacer;
wherein the carbon brush includes a first cavity extending into the carbon brush from the upper surface, and wherein the first cavity receives the first projection therein.

14. The system of claim 13 , further comprising a lead wire having a first end and a second end extending away from the first end, wherein the first end extends into the carbon brush at an insertion point at the upper surface of the carbon brush and spaced away from the first cavity.

15. The system of claim 14 , wherein the carbon brush further comprises a second cavity extending into the carbon brush from the upper surface of the carbon brush, wherein the second cavity is spaced away from the first cavity.

16. The system of claim 15 , wherein the spacer further comprises a second projection extending into the second cavity.

17. The system of claim 16 , wherein the first projection and the second projection are designed to engage the carbon brush simultaneously, and wherein the engagement of the first projection and the second projection with the carbon brush is configured to retain the spacer in a fixed relationship with the carbon brush.

18. The system of claim 17 , wherein both the first projection and the second projection extend away from a bottom surface of the spacer.

19. The system of claim 18 , wherein the bottom surface of the spacer is juxtaposed with the upper surface of the carbon brush when the first and second projections are positioned in the first and second cavities.

20. The system of claim 13 , wherein engagement of the first projection within the first cavity is configured to retain the spacer in a fixed relationship with the carbon brush.

21. The system of claim 20 , wherein the measured angular displacement of the wear state monitor correlates to an amount of diminution in the length of the carbon brush.

22. The system of claim 13 , wherein the first cavity includes a channel extending along the upper surface of the carbon brush, and wherein the first projection is configured to mate with and insert into the channel.

23. The system of claim 13 , wherein the first cavity includes a tapered surface, and wherein the first projection includes a tapered surface designed to mate with the tapered surface of the first cavity.

24. An assembly for a brush holder assembly of an electrical device, comprising:
a carbon brush including an upper surface, a lower surface opposite the upper surface, and a length measured from the upper surface to the lower surface;
one or more lead wires extending out of the carbon brush at an insertion point on the upper surface;
first and second cavities extending into the carbon brush from the upper surface at a location spaced away from the insertion point of the one or more lead wires and unobstructed by the one or more lead wires; and
a spacer having first and second projections extending from a lower surface of the spacer;
wherein the first and second projections are configured to be inserted into the first and second cavities when the lower surface of the spacer is juxtaposed with the upper surface of the carbon brush.

Assignees

• Cutsforth Inc

Inventors

• Cutsforth Robert S
• Cutsforth Dustin L
• Harrison David William Drury
• Bruey Douglas Christopher

Classifications

• H01R39/388

  characterised by the material of the brush holder · CPC title

• H01R13/6683

  with built-in sensor · CPC title

• H01R39/381

  characterised by the application of pressure to brush · CPC title

• H02K5/146

  Pivotally supported brushes or brush holders · CPC title

• H02K5/148 Primary

  Slidably supported brushes · CPC title