Viscous fluid shear device having wiper fixedly coupled to housing assembly

Patent metadata

Field	Value
Publication number	US-10851852-B2
Application number	US-201816179056-A
Country	US
Kind code	B2
Filing date	Nov 2, 2018
Priority date	Nov 6, 2017
Publication date	Dec 1, 2020
Grant date	Dec 1, 2020

Abstract

A viscous fluid shear device having a housing, a rotor, which is rotatable in the housing, and a wiper that is coupled to the housing. The housing defines a scavenge conduit and a nozzle. Viscous fluid that clings to the circumference of the rotor during operation of the viscous fluid shear device is driven through the nozzle and directed by the wiper into the scavenge conduit.

First claim

What is claimed is:

1. A viscous fluid shear device comprising:
a housing assembly that defines a working chamber having a plurality of first ribs, which are disposed concentrically about a central axis, the housing assembly comprising first and second housing members that are fixedly coupled to one another, the first housing member having a circumferentially extending wall and a viscous fluid return system, the circumferentially extending wall defining a working chamber channel having a radially inner surface, the viscous fluid return system having a wiper, a scavenge conduit and a nozzle, the wiper being unitarily and integrally formed with the circumferentially extending wall and projecting radially inwardly of the radially inner surface of the working chamber channel, the scavenge conduit having a scavenge inlet aperture, a first conduit portion and a second conduit portion, the scavenge inlet aperture being formed into the circumferentially extending wall and intersecting the wiper such that a first portion of a surface of the scavenge inlet aperture forms a leading end of the wiper, the scavenge inlet aperture being formed along a first longitudinal axis and having a first cross-sectional area taken perpendicular to the first longitudinal axis, the first conduit portion being formed in the circumferentially extending wall and intersecting the scavenge inlet aperture, the first conduit portion being formed along a second longitudinal axis, the second conduit portion intersecting the first conduit portion and extending radially inwardly therefrom, the nozzle extending circumferentially between the working chamber channel and scavenge inlet aperture, the nozzle being configured to discharge a viscous fluid directly into the scavenge inlet aperture;
a rotor received in the housing assembly and being rotatable about the central axis relative to the housing assembly in a first predetermined rotational direction, the rotor having a disk portion having a plurality of second ribs that are disposed concentrically about the central axis and juxtaposed with the first ribs; and
a reservoir disposed in the housing assembly and being in fluid communication with the scavenge conduit;
wherein the radially inner surface of the working chamber channel is disposed from a circumferentially extending surface of the rotor by a first distance, wherein at least one point on a radially inner surface of the wiper is disposed from the circumferentially extending surface of the rotor by a second distance that is smaller than the first distance and wherein a point at which the nozzle intersects the scavenge input aperture is disposed a third distance from the circumferentially extending surface of the rotor, the third distance being less than the first distance and greater than the second distance.

2. The viscous fluid shear device of claim 1 , wherein the nozzle comprises a radially outer surface, and wherein at least a portion of the radially outer surface of the nozzle has a flat, planar shape.

3. The viscous fluid shear device of claim 2 , wherein the portion of the radially outer surface of the nozzle having the flat, planar shape is disposed in a plane, wherein the plane is spaced from the central axis by a predetermined distance, and wherein the plane is sloped such that it is within +10 degrees to −5 degrees of being tangent to a circle centered at the central axis, the circle having a radius equal to the predetermined distance.

4. The viscous shear device of claim 1 , wherein the radially inner surface of the working chamber channel is formed with draft such that the radially inner surface of the working chamber channel is shaped as a portion of a surface of a frustum.

5. The viscous shear device of claim 4 , wherein a magnitude of the draft on the radially inner surface of the working chamber channel is less than or equal to 5 degrees.

6. The viscous shear device of claim 5 , wherein the magnitude of the draft on the radially inner surface of the working chamber channel is less than or equal to 3 degrees.

7. The viscous shear device of claim 4 , wherein the nozzle comprises a radially outer surface, and wherein at least a portion of the radially outer surface of the nozzle is formed with draft.

8. The viscous shear device of claim 7 , wherein a magnitude of the draft on the radially outer surface of the nozzle is less than a magnitude of the draft on the radially inner surface of the working chamber channel.

9. The viscous shear device of claim 7 , wherein the magnitude of the draft on the radially outer surface of the nozzle is less than or equal to 1.5 degrees.

10. The viscous shear device of claim 1 , wherein the surface of the scavenge inlet aperture is defined by a radius that extends perpendicular from the first longitudinal axis of the scavenge inlet aperture.

11. The viscous shear device of claim 10 , wherein the radially inner surface of the wiper is defined by a radius that extends from the central axis, wherein a first circle defined by the radius of the radially inner surface of the wiper is intersected twice by a second circle that is defined by the radius of the surface of the scavenge inlet aperture.

12. The viscous shear device of claim 10 , wherein the radius is less than or equal to 1.5 mm.

13. The viscous shear device of claim 1 , wherein the first and second longitudinal axes are coincident.

14. The viscous shear device of claim 1 , wherein the reservoir is coupled to the housing assembly for rotation therewith.

15. The viscous shear device of claim 1 , wherein the circumferentially extending surface of the rotor extends laterally into the first housing member past the scavenge inlet aperture.

16. The viscous shear device of claim 1 , wherein the working chamber channel terminates at a circumferentially extending shoulder, and wherein the nozzle comprises a first lateral ramp that extends laterally between at least a portion of a span between the circumferentially extending shoulder and the scavenge inlet aperture.

17. The viscous shear device of claim 16 , wherein the first housing member further defines a first rotor bore that is formed in the circumferentially extending wall, the first rotor bore being smaller in diameter than the working chamber channel, the first rotor bore extending laterally into the first housing member, the circumferentially extending surface of the rotor extending laterally beyond the working cavity into the first rotor bore.

18. The viscous shear device of claim 17 , wherein the first rotor bore is larger in diameter than the circumferentially extending surface of the rotor by an amount that is less than or equal to 1.5 mm and greater than or equal to 0.5 mm.

19. The viscous shear device of claim 18 , wherein the amount is less than or equal to 0.8 mm.

20. The viscous shear device of claim 17 , wherein the second housing member defines a second rotor bore, wherein the circumferentially extending surface of the rotor extends laterally into the second rotor bore.

21. The viscous shear device of claim 20 , wherein the second housing member defines a working chamber groove that is formed into an abutment surface of the second housing member that faces the first housing member, the working chamber groove having a root surface, and wherein the nozzle comprises a second lateral ramp that extends laterally between at least a portion of a span between the root surface and the scavenge input aperture.

22. The viscous shear device of claim 21 , wherein the abutment surfa

Assignees

• Borgwarner Inc

Inventors

• Light Gerard M
• Stagg Jonathan B

Classifications

• F24V40/00 Primary

  Production or use of heat resulting from internal friction of moving fluids or from friction between fluids and moving bodies · CPC title

• F16D35/023 Primary

  the valve being actuated by a bimetallic coil (F16D35/026 takes precedence) · CPC title

• F16D35/022

  the valve being actuated by a bimetallic strip (F16D35/026 takes precedence) · CPC title

• F16D2300/26

  Cover or bell housings; Details or arrangements thereof · CPC title