Transmission with mechanically-biased clutch

A transmission configured to receive power from an engine, comprising:

• an input member and an output member;
• a transmission gearing arrangement including a plurality of intermeshing gear members;
• a stationary member;
• a plurality of clutches selectively engagable in different combinations to establish different operating modes between the input member and the output member;
• wherein each of the clutches is selectively engagable to transmit torque between different ones of the input member, the output member, and the gear members, or to ground one of the input member and the gear members to the stationary member;
• wherein the plurality of clutches includes at least one normally-closed clutch having an engaged state and a disengaged state;
• wherein the normally-closed clutch includes a mechanical member;
• a hydraulically-actuated valve having a first and a second piston and a piston support connecting the first and the second piston;
• wherein the hydraulically-actuated valve at least partially defines a first annular chamber at the first piston and a second annular chamber at the second piston;
• wherein the piston support is operatively connected to the mechanical member such that the mechanical member is movable to a first position by application of hydraulic pressure in the first annular chamber to place the normally-closed clutch in the engaged state and is movable to a second position by application of hydraulic pressure in the second annular chamber to place the normally-closed clutch in the disengaged state;
• and
• wherein the mechanical member is configured to retain the clutch in the engaged state without application of power, including at least hydraulic, pneumatic, and electrical.

A transmission configured for receiving power from an engine comprising:

• an input member connectable with the engine;
• an output member;
• a stationary member;
• a transmission gearing arrangement operatively connected between the input member and the output member and including a plurality of rotatable gear members;
• a clutch having an engaged state and a disengaged state;
• wherein the clutch transmits torque between one of the gear members and another of the gear members, between said one of the gear members and the stationary member, or between the engine and the transmission when in the engaged state, and does not transmit torque when in the disengaged state;
• wherein the clutch includes a mechanical member selectively movable to a first position in which the mechanical member is configured to retain the clutch in the engaged state without application of power, including at least hydraulic, pneumatic, and electrical power;
• wherein the mechanical member is further selectively movable to second position in which the mechanical member is configured to retain the clutch in the disengaged state without application of power, including at least hydraulic, pneumatic, and electrical power;
• a first rotatable shaft continuously connected with said one of the gear members;
• wherein the clutch includes a housing, a first set of plates continuously connected with the housing, and a second set of plates continuously connected with the first rotatable shaft;
• and wherein the second set of plates is selectively engaged with the first set of plates via the mechanical member when the clutch is in the engaged state;
• a hydraulically-actuated valve having a first and a second piston and a piston support connecting the first and the second piston;
• wherein the hydraulically-actuated valve at least partially defines a first annular chamber at the first piston and a second annular chamber at the second piston;
• wherein the piston support is operatively connected to the mechanical member such that the mechanical member is movable to the first position by application of hydraulic pressure in the first annular chamber to place the clutch in the engaged state and is movable to a second position by application of hydraulic pressure in the second annular chamber to place the clutch in the disengaged state;
• and
• a plurality of levers operatively connected to the mechanical member and to the piston support and configured to pivot at the housing and to provide a mechanical advantage between the hydraulically-actuated valve and the mechanical member.