Alternator having an external ignition protection system

Patent metadata

Field	Value
Publication number	US-2018183293-A1
Application number	US-201715400501-A
Country	US
Kind code	A1
Filing date	Jan 6, 2017
Priority date	Dec 22, 2016
Publication date	Jun 28, 2018
Grant date	—

Abstract

An alternator includes an external ignition protection system including a shaft rotatable about an axis. The shaft includes a slip ring end. A slip ring support is mounted at the slip ring end of the shaft. A slip ring cover is mounted to the shaft. The slip ring cover defines a slip ring cavity. A first slip ring end housing supports the slip ring cover. The first slip ring end housing includes a first plurality of openings. A second slip ring end housing is arranged axially outwardly of the slip ring end. The second slip ring end housing includes a second plurality of openings. The first slip ring end housing, slip ring cover and the second slip ring end housing define a labyrinth flow path that provides an air flow through the slip ring cavity and prevents passage of ignition inducing elements from the alternator.

First claim

What is claimed is:

1 . An alternator including an external ignition protection system comprising:
a shaft rotatable about an axis, the shaft including a slip ring end; a slip ring support mounted at the slip ring end of the shaft; at least two slip rings mounted to the slip ring support; a slip ring cover mounted to the shaft over the at least two slip rings, the slip ring cover defining a slip ring cavity; a first slip ring end housing arranged axially inwardly of the slip ring end supports the slip ring cover, the first slip ring end housing including a first plurality of openings; and a second slip ring end housing arranged axially outwardly of the slip ring end, the second slip ring end housing including a second plurality of openings, the first slip ring end housing, slip ring cover and the second slip ring end housing defining a labyrinth flow path that provides an air flow through the slip ring cavity and prevents passage of ignition inducing elements from the alternator.

2 . The alternator according to claim 1 , wherein the second slip ring end housing includes a central housing portion having an inner surface, and a peripheral wall, the second plurality of openings being formed in the peripheral wall.

3 . The alternator according to claim 2 , wherein the inner surface of the central housing portion includes a plurality of grooves extending radially inwardly from corresponding ones of the second plurality of openings.

4 . The alternator according to claim 2 , wherein the second slip ring end housing includes a deflector member extending across each of the plurality of second openings, the deflector member changing a direction of air entering the second slip ring end housing.

5 . The alternator according to claim 2 , wherein the first slip ring end housing includes a peripheral side wall portion defining a bearing housing and a slip ring cover support surface extending radially inwardly from the peripheral side wall portion, the first plurality of openings being formed in the slip ring cover support surface.

6 . The alternator according to claim 5 , wherein the slip ring cover support surface includes a plurality of grooves extending radially inwardly from corresponding ones of the first plurality of openings.

7 . The alternator according to claim 6 , further comprising: a first insert arranged in the central housing portion extending over the plurality of grooves to form a plurality of passages.

8 . The alternator according to claim 7 , further comprising: a second insert arranged in the first insert, the second insert formed from a material responsive to thermal expansion of one or more alternator components.

9 . The alternator according to claim 1 , wherein the slip ring cover includes an axial end portion having an opening fluidically connecting the first and second plurality of openings with the slip ring cavity.

10 . The alternator according to claim 9 , further comprising: a cover member arranged at the axial end portion of the slip ring cover, the cover member being received by the second slip ring end housing.

11 . The alternator according to claim 10 , wherein the cover member includes an opening fluidically connecting the second plurality of openings and the slip ring cavity through the slip ring cover.

12 . The alternator according to claim 10 , wherein the cover member is formed from an elastomeric material.

13 . The alternator according to claim 10 , wherein the second slip ring end housing includes an inspection opening providing a line of sight to the cover member.

14 . The alternator according to claim 1 , further comprising: a brush housing supported by the slip ring cover.

15 . The alternator according to claim 14 , wherein the brush housing is integrally formed with the slip ring cover.

16 . The alternator according to claim 14 , further comprising: a voltage regulator supported by the slip ring cover.

17 . The alternator according to claim 16 , wherein the voltage regulator is integrally formed with the slip ring cover.

18 . The alternator according to claim 1 , further comprising: a bearing supporting the shaft spaced from the slip ring end, the second slip ring end housing extending about the bearing.

19 . The alternator according to claim 1 , wherein the second slip ring end housing includes an annular groove, the slip ring cover including an annular lip received by the annular groove.

20 . The alternator according to claim 1 , wherein the first plurality of openings defines a fluid outlet and the second plurality of openings defines a fluid inlet.

21 . The alternator according to claim 2 , wherein the second plurality of openings are directed toward a direction of gravity.

22 . The alternator according to claim 21 , wherein the second slip ring end housing includes a deflector member extending across each of the plurality of second openings, the deflector member changing a direction of air entering the second slip ring end housing.

Assignees

• Borgwarner Inc

Inventors

• Neet Kirk E
• Chen George
• Teng mark
• Wang Yijun

Classifications

• H02K7/108

  with friction clutches · CPC title

• H02K5/141

  for cooperation with slip-rings · CPC title

• H02K19/365

  with a voltage regulator · CPC title

• H02K9/28

  Cooling of commutators, slip-rings or brushes e.g. by ventilating · CPC title

• H02K5/136

  explosion-proof · CPC title