Improved torque responsive fluid coupling device

Claim 2

In a fluid coupling device of the type including a first rotatable coupling member (13) defining an axis of rotation, cover means (27) associated with the first coupling member to define a fluid chamber therebetween, means (31) disposed to separate the fluid chamber into a fluid operating chamber (33) and a fluid reservoir chamber (35), a second rotatable coupling member (11) disposed in the fluid operating chamber and being rotatable relative to the first coupling member, the first and second coupling members cooperating to define a shear space (space between 39 & 41) therebetween and operable to transmit torque in response to the presence of fluid therein, the improvement comprising: (a) the separating means defining fluid orifice means (45) operable to permit fluid communication between the fluid operating chamber and the fluid reservoir chamber; (b) pump means (47) operatively associated with one of the separating means and the first rotatable coupling member to pump fluid from the operating chamber through the fluid orifice means to the reservoir chamber, to achieve a disengaged condition, when the difference between the rotational speeds of the first and second coupling members exceeds a predetermined value; (c) said fluid orifice means being selected such that, below said predetermined value of the speed difference, centrifugal force acting on fluid in the reservoir chamber overcomes the pressure generated by said pump means to cause fluid to flow from the reservoir chamber through said fluid orifice means to the operating chamber, to achieve an engaged condition.

Claim 3

The improvement as claimed in claim 1 wherein said fluid orifice means consists essentially of an opening (45) operatively associated with said pump means, substantially all fluid communicated between the operating chamber and the reservoir chamber flowing through said opening.

Claim 4

The improvement as claimed in claim 1 wherein said fluid orifice means comprises an opening operatively associated with said pump means, fluid communication between the operating chamber and the reservoir chamber, in both directions, flowing through said opening, said fluid orifice means further comprising a secondary fill orifice (49) to communicate fluid from the reservoir chamber to the operating chamber.

Claim 5

The improvement as claimed in claim 1 wherein the separating means comprises an annular, plate-like member (31) fixed relative to the first rotatable coupling member.

Claim 6

A fluid coupling device consisting essentially of: (a) a first rotatable coupling member (13); (b) a cover member (27) associated with said first coupling member to define a fluid chamber therebetween; (c) a separator plate (31) disposed to separate said fluid chamber (33) into a fluid operating chamber and a fluid reservoir chamber (35); (d) a second rotatable coupling member disposed in said operating chamber and being rotatable relative to said first coupling member, said first and second coupling members cooperating to define a shear space (space between 39 & 41) therebetween and operable to transmit torque in response to the presence of fluid therein; (e) said separator plate defining a first fluid orifice (45) disposed to permit fluid communication between said reservoir chamber and said operating chamber, and a second fluid orifice (49) disposed to permit fluid communication from said reservoir chamber to said operating chamber; (f) a pumping element (47) operatively associated with one of said separator plate and said first rotatable coupling member to pump fluid from said operating chamber through said first fluid orifice to said reservoir chamber to achieve a disengaged condition, when the difference between the rotational speeds of said first and second members exceeds a predetermined value; (g) said first and second fluid orifices being sized and located such that, below said predetermined value of speed difference, centrifugal force acting on fluid in said reservoir chamber overcomes the pressure generated by said pumping element to cause fluid to flow from said reservoir chamber through said first and second fluid orifices to said operating chamber, to achieve an engaged condition.

Claim 7

A fluid coupling device consisting essentially of: (a) a first rotatable coupling member (13); (b) a cover member (27) associated with said first coupling member to define a fluid chamber therebetween; (c) a separator plate (31) disposed to separate said fluid chamber (33) into a fluid operating chamber and a fluid reservoir chamber (35); (d) a second rotatable coupling member disposed in said operating chamber and being rotatable relative to said first coupling member, said first and second coupling members cooperating to define a shear space (space between 39 & 41) therebetween and operable to transmit torque in response to the presence of fluid therein; (e) said separator plate defining a first fluid orifice (45) disposed to permit fluid communication between said reservoir chamber and said operating chamber, and a second fluid orifice (49) disposed to permit fluid communication from said reservoir chamber to said operating chamber; (f) a pumping element (47) operatively associated with one of said separator plate and said first rotatable coupling member to pump fluid from said operating chamber through said first fluid orifice to said reservoir chamber to achieve a disengaged condition, when the difference between the rotational speeds of said first and second members exceeds a predetermined value; (g) said first and second fluid orifices being sized and located such that, below said predetermined value of speed difference, centrifugal force acting on fluid in said reservoir chamber overcomes the pressure generated by said pumping element to cause fluid to flow from said reservoir chamber through said first and second fluid orifices to said operating chamber, to achieve an engaged condition.