Fluid coupling device having more responsive engagement and disengagement

Claim 2

A fluid coupling device comprising a first rotatable coupling member defining an axis of rotation, cover means associated with said first member to define a fluid chamber therebetween, valve means disposed to separate said fluid chamber into a fluid operating chamber and a fluid reservoir chamber, a second rotatable coupling member disposed in said fluid operating chamber and being rotatable relative to said first coupling member, said valve means being operable to control the flow of fluid between said reservoir chamber and said operating chamber, and including means associated with said valve means to effect the operation of said valve means in response to variations in a predetermined condition, said second coupling member being generally disc-like and having one face disposed adjacent said valve means and an opposite face, said opposite face of said second coupling member and the adjacent surface of said first coupling member cooperating to define a plurality of interdigitated lands and grooves defining a shear space therebetween and operable to transmit torque in response to the presence of fluid therein, said second coupling member defining fluid passage means operable to communicate fluid generally axially between said one face and said interdigitated lands and grooves said interdigitated lands and grooves being substantially uninterrupted by said fluid passage means.

Claim 3

A fluid coupling device as claimed in claim 1 wherein said valve means includes a valve plate separating said operating chamber and said reservoir chamber and defining a fluid inlet port and a fluid discharge port.

Claim 4

A fluid coupling device as claimed in claim 2, wherein said valve means includes a movable valve member operable between a first position permitting fluid flow through said inlet port into said operating chamber and a second position substantially blocking fluid flow through said inlet port.

Claim 5

A fluid coupling device as claimed in claim 2 or 3 wherein said fluid discharge port is disposed adjacent the radially outermost extent of said fluid passage means and said fluid inlet port is disposed adjacent the radially innermost extent of said fluid passage means.

Claim 6

A fluid coupling device as claimed in claim 1 or 2 wherein said fluid passage means provides fluid communication over substantially the entire radial extent of said interdigitated lands and grooves.

Claim 7

A fluid coupling device as claimed in claim 1 wherein said fluid passage means comprises a plurality of substantially identical passages uniformly disposed circumferentially.

Claim 8

A fluid coupling device as claimed in claim 1 wherein the radial extent of said fluid passage means coincides approximately with the radial extent of said interdigitated lands and grooves.

Claim 9

A fluid coupling device comprising a rotatable output coupling member defining an axis of rotation, a cover member associated with said output member to define a fluid chamber therebetween, a valve plate disposed to separate said fluid chamber into a fluid operating chamber and a fluid reservoir chamber, a rotatable input coupling member disposed in said fluid operating chamber and being rotatable relative to said output member, said valve plate including valve means operable to control the flow of fluid between said reservoir chamber and said operating chamber, said valve means including temperature responsive means operable to control said valve means in response to variations in a predetermined temperature condition, said input coupling member including a generally annular disc portion having a front face disposed adjacent said valve plate, and a rear face, said rear face of said input coupling member and the adjacent surface of said output coupling member cooperating to define a plurality of interdigitated lands and grooves defining a shear space therebetween and operable to transmit torque in response to the presence of fluid therein, said disc portion of said input member defining a plurality of fluid passages operable to communicate fluid generally axially from said front face into said grooves by said rear race of said input coupling member, said lands and grooves defined by said input member being substantially uninterrupted by said fluid passages.

Claim 10

A fluid coupling device comprising a rotatable output coupling member defining an axis of rotation, a cover member associated with said output member to define a fluid chamber therebetween, a valve plate disposed to separate said fluid chamber into a fluid operating chamber and a fluid reservoir chamber, a rotatable input coupling member disposed in said fluid operating chamber and being rotatable relative to said output member, said valve plate including valve means operable to control the flow of fluid between said reservoir chamber and said operating chamber, said valve means including temperature responsive means operable to control said valve means in response to variations in a predetermined temperature condition, said input coupling member including a generally annular disc portion having a front face disposed adjacent said valve plate, and a rear face, said rear face of said input coupling member and the adjacent surface of said output coupling member cooperating to define a plurality of interdigitated lands and grooves defining a shear space therebetween and operable to transmit torque in response to the presence of fluid therein, said disc portion of said input member defining a plurality of fluid passages operable to communicate fluid generally axially from said front face into said grooves by said rear race of said input coupling member, said lands and grooves defined by said input member being substantially uninterrupted by said fluid passages.