COMMUTATOR

• US 20100314966A1
• Filed: 06/16/2010
• Published: 12/16/2010
• Est. Priority Date: 06/16/2009
• Status: Active Grant

• Current Assignee: Johnson Electric SA 125 Rue de Progres La Chaux de Fonds Switzerland (Johnson Electric Holdings Limited)
• Original Assignee: Johnson Electric SA 125 Rue de Progres La Chaux de Fonds Switzerland (Johnson Electric Holdings Limited)
• Inventors: Gorlt, Wilfried
• Granted Patent: US 8,418,351 B2
• Time in Patent Office: Days
• US Class Current: 310/234
• CPC Class Codes: H01R 39/06 other than with external cylindrical contact surface, e.g. flat commutators
• CPC Class Codes: H01R 43/06 Manufacture of commutators
• CPC Class Codes: Y10T 29/49009 Dynamoelectric machine
• CPC Class Codes: Y10T 29/49011 Commutator or slip ring assembly

Abstract

A commutator has an electrically non-conductive base and a plurality of commutator segments fixed to the base. Each segment comprises an electrically conductive connector and a segment part, wherein the connector has a segment portion, a terminal portion and anchors all formed as a monolithic construction. The terminal and anchors extend from the segment portion at radial ends thereof. The anchors fix the connectors to the base by being embedded therein. The segment part is a part of an annular disc forming an electrically conductive brush-contacting layer fixed to a side of the segment portion remote from the base. The segment portions are circumferentially separated by slits into which the base extends and the segment parts are separated circumferentially by slots. The slots are aligned with the slits, are narrower than the slits and extend axially into the material of the base within the slits between adjacent connectors.

Claims

1. A method of manufacturing a commutator which comprises an electrically non-conductive base supporting a plurality of commutator segments forming a planer brush contact surface, each segment having a connector and a segment part fixed to the connector, the method comprising the steps of:

forming a connector plate having a plurality of connectors arranged circumferentially about a central opening and interconnected by links, each connector having a terminal portion, a segment portion and a number of anchors, adjacent segment portions being separated circumferentially by slits, the segment portions having a first face and a second face opposite the first face,

fixing a conductive layer on the first face of the segment portions to form a brush contacting surface,

severing the links to separate the connectors,

fixing the base to the second face of the connectors,

separating the conductive layer into circumferentially arranged segment parts by cutting radial slots through the conductive layer aligned with the slits, the width of the slots being narrower that the width of the slits to avoid cutting the connectors.

2. The method of claim 1, further comprising the step of providing the conductive layer in the form of an annular disc.

3. The method of claim 1, wherein the step of fixing a conductive layer on the first face of the segment portions to form a brush contacting surface, includes providing the conductive layer in the form of an annular disc of a conductive material containing graphite and soldering the annular disc to the segment portions of the connectors.

4. The method of claim 1, wherein the step of fixing the base to the second face of the connectors further comprises molding the base directly to the connectors before the conductive layer is cut into segment parts, embedding the anchors in the base and filling gaps formed by the slits between the connectors with material of the base.

5. The method of claim 4, further comprising the step of cutting the slots through the conductive layer to an axial depth sufficient to cut the material of the base within the slits without the slots extending beyond the second face of the connectors.

6. The method of claim 1, further comprising the steps of forming the links at the outermost ends of the slits in a radial direction of the connector plate, and severing the links after the conductive layer is fixed to the connector plate.

7. The method of claim 2, further comprising the step of forming the base by molding after the step of severing the links.

8. The method of claim 1, further comprising the step of forming inner and outer anchors on the connectors and forming the links between the outer anchors of adjacent connectors at the outermost ends of the slits in a radial direction of the connector plate.

9. The method of claim 1, further comprising the step of forming the links at the distal ends of the anchors with each link connecting the distal ends of two anchors of adjacent connectors.

11. The commutator of claim 9, wherein the slots extend into the body in the corresponding slits without contacting the connector.

12. The commutator of claim 9, wherein the annular disc is of material containing graphite.

10. A commutator comprising:

an electrically non-conductive base,

a plurality of commutator segments fixed to the base, each segment comprising an electrically conductive connector and a segment part,

wherein the connector has a segment portion, a terminal portion and anchors all formed as a monolithic construction, the terminal and anchors extending from the segment portion at radial ends thereof, the anchors being embedded in the base;

wherein the segment part is a part of an annular disc forming an electrically conductive brush-contacting layer fixed to a side of the segment portion remote from the base, and

wherein the segment portions are circumferentially separated by slits into which the base extends and the segment parts are separated circumferentially by slots, the slots are aligned with the slits, are narrower than the slits and extend axially into the base within the slits between the connectors.