Accessory drive with friction clutch

Patent metadata

Field	Value
Publication number	US-9458897-B2
Application number	US-201414149694-A
Country	US
Kind code	B2
Filing date	Jan 7, 2014
Priority date	Dec 24, 2012
Publication date	Oct 4, 2016
Grant date	Oct 4, 2016

Abstract

An ON-OFF vehicle accessory for driving vehicle cooling pump or cooling fan. The accessory having a friction clutch assembly with a friction plate member connected to a central rotatable shaft member. A biased armature member is adapted to force a friction plate member with friction linings thereon against a housing or cover which is rotating at input speed. A solenoid assembly is used to overcome the spring bias and pull the armature and friction plate member away from the housing.

First claim

What is claimed is:

1. An accessory drive assembly comprising:
a housing;
an input member that is rotatable relative to the housing about an axis;
a shaft received in the housing and rotatable about the axis;
a solenoid assembly that is coupled to the housing and disposed about the shaft, the solenoid assembly having an electromagnetic coil;
a friction plate that is non-rotatably but slidably disposed on the shaft, the friction plate being movable along the axis between a first friction plate position, in which the friction plate is coupled to the input member for common rotation, and a second friction plate position in which the friction plate is decoupled from the input member;
an armature coupled to the input member for rotation therewith, the armature being disposed about the shaft and movable along the axis relative to the shaft between a first armature position, in which the armature is coupled to the friction plate for common rotation, and a second armature position, the armature having a plurality of spring retaining members; and
a plurality of coil springs, each of the coil springs being positioned on a corresponding one of the spring retaining members, the coil springs biasing the armature toward the first armature position;
wherein the electromagnetic coil is selectively operable to generate a magnetic field that causes the armature to move toward the second armature position such that the armature.

2. The accessory drive assembly of claim 1 , wherein the accessory drive assembly provides a flux path for axially moving the armature when the the magnetic field is generated by the electromagnetic coil, the flux path comprising a path through said solenoid assembly, said input member, said armature, back to said input member and then back to said solenoid assembly.

3. The accessory drive assembly of claim 1 , further comprising a return spring member for biasing the friction plate axially toward the second friction plate position.

4. The accessory drive assembly of claim 1 , further comprising one of an impeller and a fan that is coupled to the shaft for rotation therewith.

5. The accessory drive assembly of claim 1 , further comprising a stop member that is fixedly coupled to the shaft, wherein the friction plate comprises a plate member, and wherein the stop member limits movement of the plate member in direction along the axis.

6. The accessory drive assembly of claim 5 , wherein the stop member is press fit on the shaft.

7. The accessory drive assembly of claim 5 , wherein one of the plate member and the stop member defines a plurality of openings spaced circumferentially around the axis, and wherein the other one of the plate member and the stop member defines a plurality of lugs that are spaced circumferentially around the axis, and wherein each of the lugs is slidably received into a corresponding one of the openings.

8. The accessory drive assembly of claim 1 , wherein the friction plate comprises a plate member and a pair of friction lining members coupled to opposite axial sides of the plate member.

9. The accessory drive assembly of claim 8 , wherein each of said friction lining members comprise annular rings of friction lining material.

10. The accessory drive assembly of claim 1 , further comprising a cover that is coupled to the input member for common rotation, and wherein the friction plate is frictionally engaged to the cover when the friction plate is in the first friction plate position.

11. The accessory drive assembly of claim 10 , wherein an attachment is employed to couple the cover to the input member, wherein the attachment is selected from a group consisting of press-fits, roll-overs, welding and combinations thereof.

12. The accessory drive assembly of claim 10 , wherein the input member is a pulley.

13. The accessory drive assembly of claim 10 , wherein the armature is directly mounted to the cover.

14. The accessory drive assembly of claim 13 , wherein one of the cover and the armature includes a plurality of tabs and wherein the other one of the cover and the armature defines a plurality of notches into which the tabs are received to thereby non-rotatably but axially slidably couple the armature to the cover.

15. An accessory drive comprising:
a housing;
a shaft received through the housing, the shaft being rotatable about an axis;
a solenoid assembly having an electromagnetic coil, the solenoid assembly being coupled to the housing and disposed about the shaft;
an input member that is rotatable relative to the housing about the axis;
a cover coupled to the input member and rotatable therewith, the cover cooperating with the input member to define a clutch cavity;
an armature that is disposed about the shaft and received in the clutch cavity, the armature being movable along the axis between a first armature position and a second armature position;
biasing members biasing the armature toward the first armature position;
a friction plate having a plate member, the plate member being non-rotatably but axially slidably received on the shaft, the friction plate being movable between a first friction plate position and a second friction plate position; and
a stop member fixedly coupled to the shaft, the plate member being non-rotatably but axially slidably mounted on the stop member;
wherein the armature positions the friction plate into frictionally engagement with the cover when the armature is in the first armature position, wherein the electromagnetic coil is selectively operable to generate a magnetic field that causes the armature to move toward the second armature position to de-engage the friction plate and the cover;
wherein the stop member restricts axial movement of the friction plate member when the armature moves toward the second armature position in response to the magnetic field that is generated by the electromagnetic coil.

16. The accessory drive assembly of claim 15 , wherein the stop member is press fit on said shaft.

17. The accessory drive assembly of claim 15 , wherein one of the plate member and the stop member defines a plurality of openings spaced circumferentially around the axis, and wherein the other one of the plate member and the stop member defines a plurality of lugs that are spaced circumferentially around the axis, and wherein each of the lugs is slidably received into a corresponding one of the openings.

18. The accessory drive assembly of claim 15 , wherein the accessory drive assembly provides a flux path for axially moving the armature when the the magnetic field is generated by the electromagnetic coil, the flux path comprising a path through said solenoid assembly, said input member, said armature, back to said input member and then back to said solenoid assembly.

19. The accessory drive assembly of claim 15 , further comprising a return spring that biases the toward the second friction plate position.

20. The accessory drive assembly of claim 15 , wherein the input member defines a plurality of openings that are disposed circumferentially about the axis, the openings being disposed in-line with the electromagnetic coil and the armature.

21. The accessory drive assembly of claim 15 , wherein one of the cover and the armature includes a plurality of tabs and wherein the other one of the cover and the armature defines a plurality of notches into which the tabs are received to thereby non-rotatably but axially slidably couple the armature to the cover.

22. The accessory drive assembly of claim

Assignees

• Borgwarner Inc

Inventors

• Qin Shiwei

Classifications

• F16D2027/008

  Details relating to the magnetic circuit, or to the shape of the clutch parts to achieve a certain magnetic path · CPC title

• F16D27/112 Primary

  with flat friction surfaces, e.g. discs · CPC title