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A hydrostatic transmission including a pump, a motor, and a center section provided with a conduit through which the pump and motor are in fluid communication and a valve. The pump, motor and center section are disposed in a housing having a plurality of walls which at least partially define a sump,

A hydrostatic transmission including a pump, a motor, and a center section provided with a conduit through which the pump and motor are in fluid communication and a valve. The pump, motor and center section are disposed in a housing having a plurality of walls which at least partially define a sump, the conduit being in fluid communication with the sump through the valve when the valve is open. A hydraulic disconnect mechanism is provided which includes a substantially rigid first portion, and a second portion operatively engaged with the first portion and being at least partially resilient. The valve is operably engaged with and opened by the second portion in response to the first portion being in an engaged position, and the valve is not operably engaged with the second portion when the first portion is in a disengaged position.

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1. A hydrostatic transmission comprising:a hydraulic pump having an input; a hydraulic motor having an output; a center section to which said pump and motor are rotatably mounted, said center section being provided with a conduit through which said pump and motor are in fluid communication, said pum

1. A hydrostatic transmission comprising:a hydraulic pump having an input; a hydraulic motor having an output; a center section to which said pump and motor are rotatably mounted, said center section being provided with a conduit through which said pump and motor are in fluid communication, said pump and motor being hydraulically coupled when said pump and motor are in operative fluid engagement with each other through fluid in said conduit, said center section having a valve with open and closed conditions; a housing in which said pump, motor and center section are disposed, said housing having a plurality of walls which at least partially define a sump, said conduit being in fluid communication with said sump through said valve when said valve is open, during which said pomp and motor are out of operative fluid engagement with each other, said conduit being out of fluid communication with said sump through said valve when said valve is closed; and a hydraulic disconnect mechanism comprising: a first portion which is moveable relative to said center section and extends through a said housing wall, said first portion being substantially rigid and having engaged and disengaged positions; a second portion operatively engaged with said first portion and which is moveable relative to said center section, said second portion being at least partially resilient and having a part which is substantially immobile relative to said housing; and wherein said valve is operably engaged with and opened by said hydraulic disconnect mechanism second portion in response to said hydraulic disconnect mechanism first portion being in its said engaged position, and said valve is not operably engaged with said second portion when said first portion is in its said disengaged position. 2. The transmission of claim 1, wherein said hydraulic disconnect mechanism is actuated from a location outside of said transmission housing via movement of its said first portion.3. The transmission of claim 2, wherein said hydraulic disconnect mechanism first portion comprises a rotating leg having an axis of rotation, and the actuating movement of said first portion is a rotational movement of said rotating leg about said axis of rotation.4. The transmission of claim 3, wherein said hydraulic disconnect mechanism first portion further comprises a pivoting leg extending from said rotating leg, and the actuating movement of said first portion is a pivoting movement of said pivoting leg about said axis of rotation.5. The transmission of claim 2, wherein said first portion has an axis of rotation, and the actuating movement of said first portion is a rotational movement of said first portion about said axis of rotation.6. The transmission of claim 1, wherein said hydraulic disconnect mechanism first portion is mechanically biased into one of its said engaged and disengaged positions.7. The transmission of claim 1, wherein said hydraulic disconnect mechanism first and second portions are separate, interacting elements.8. The transmission of claim 7, wherein said first portion is a rod having an axis of rotation and a lateral edge, said rod being rotatable about said axis of rotation between its said engaged and disengaged positions, and said Second portion is a resilient plate which is moved by said lateral edge into operative engagement with said valve in response to rotation of said first portion from its said disengaged position to its said engaged position.9. The transmission of claim 7, wherein said first portion is a rod having an axis of rotation and a substantially planar surface which defines an edge, said axis of rotation and said planar surface being substantially parallel, and said second portion is a resilient plate attached to said center section and having a planar surface which overlies said rod planar surface, said plate and rod planar surfaces being substantially parallel in said rod disengaged position, said rod edge bearing against said plate planar surface and elastically deforming said plate in said rod engaged position.10. The transmission of claim 1, wherein said center section is provided with a pair of said conduits through which said pump and motor are in fluid communication, said pump and motor being hydraulically coupled when said pump and motor are in operative fluid engagement with each other through fluid in one of said conduits, and a pair of said valves, each said valve having open and closed conditions, each said conduit respectively being in fluid communication with said sump through a said valve when that said valve is open, during which said pump and motor are out of fluid engagement with each other through fluid in the respective conduit.11. The transmission of claim 10, wherein each of said pair of valves is operatively engaged with and opened by said hydraulic disconnect mechanism second portion in response to said hydraulic disconnect mechanism first portion being in its engaged position.12. The transmission of claim 11, wherein both of said pair of valves are simultaneously operatively engaged with and opened by said hydraulic disconnect mechanism second portion in response to said hydraulic disconnect mechanism first portion being in its engaged position.13. The transmission of claim 11, wherein said hydraulic disconnect mechanism second portion is provided with a pair of projections, each of which is operatively engaged with a said valve in said valve open condition.14. The transmission of claim 1, wherein said hydraulic disconnect mechanism first and second portions are rotatably fixed together.15. The transmission of claim 14, wherein said first portion is a rod having an axis of rotation, said rod being rotatable about said axis of rotation between its said engaged and disengaged positions, and said second portion is a resilient wire having a projection formed therein which is moved out of operative engagement with said valve in response to rotation of said first portion from its said engaged position to its said disengaged position.16. The transmission of claim 15, wherein said wire extends longitudinally in a direction substantially parallel with said axis of rotation.17. The transmission of claim 15, wherein said wire has a terminal end portion which is fixed relative to said housing.18. The transmission of claim 1, wherein said transmission is a transaxle, and further comprises an axle operatively engaged with said motor output.19. The transmission of claim 1, wherein said valve is biased into its said closed condition.20. A hydrostatic transmission comprising:a housing partially defining a sump in which is provided hydrostatic fluid; an axial piston pump having a rotatable input shaft; an axial piston motor having a rotatable output shaft; a center block to which said pump and motor are rotatably connected, said pump and motor being hydraulically connected through first and second fluid conduits extending through said center block, said pump, motor and conduits defining a hydraulic circuit, said center block further having first and second check valves respectively located between said sump and said first and second conduits, hydrostatic fluid in said sump being automatically drawn into said hydraulic circuit through said valves; and a hydraulic bypass mechanism comprising operatively engaged first and second portions, said first portion extending through said housing and being manually moved by an operator to one of an engaged and a disengaged position, said second portion being located in said sump said second portion having a part which is substantially fixed relative to said center block and a part which is movable relative to said center block, said check valves being held open by said second portion in said first portion engaged position wherein fluid flow from said conduits to said sump through said check valves is facilitated, said second portion being out of operative engagement with said valves in said first portion disengaged positron wherein fluid flow from said conduits to said sump is prevented by said check valves, wherein said hydraulic bypass mechanism first portion is biased into its said engaged position. 21. A hydrostatic transmission comprising:a housing partially defining a sump in which is provided hydrostatic fluid; an axial piston pump having a rotatable input shaft; an axial piston motor having a rotatable output shaft; a center block to which said pump and motor are rotatably connected, said pump and motor being hydraulically connected through first and second fluid conduits extending through said center block, said pump, motor and conduits defining a hydraulic circuit, said center block further having first and second check valves respectively located between said sump and said first and second conduits, hydrostatic fluid in said sump being automatically drawn into said hydraulic circuit through said valves; and a hydraulic bypass mechanism comprising a first portion operatively engaged with a unitary second portion, said first portion extending through said housing and being manually moved by an operator to one of an engaged and a disengaged position, said check valves being held open by said second portion in said first portion engaged position wherein fluid flow from said conduits to said sump through said check valves is facilitated, said second portion being out of operative engagement with said valves in said first portion disengaged position wherein fluid flow from said conduits to said sump is prevented by said check valves, wherein said hydraulic bypass mechanism second portion is elastically deformable, said second portion being elastically deformed when displaced by said hydraulic bypass mechanism first portion. 22. The transmission of claim 21, wherein said second portion comprises a resilient plate.23. The transmission of claim 21, wherein said second portion comprises a resilient wire.24. The transmission of claim 21, wherein said hydraulic bypass mechanism second portion is provided with first and second projections which are respectively moved into and out of engagement with said first and second check valves.25. A hydrostatic transmission comprising:a housing partially defining a sump in which is provided hydrostatic fluid; an axial piston pump having a rotatable input shaft; an axial piston motor having a rotatable output shaft; a center block to which said pump and motor are rotatably connected, said pump and motor being hydraulically connected through first and second fluid conduits extending through said center block, said pump, motor and conduits defining a hydraulic circuit, said center block further having first and second check valves respectively located between said sump and said first and second conduits, hydrostatic fluid in said sump being automatically drawn into said hydraulic circuit through said valves; and a hydraulic bypass mechanism comprising operatively engaged first and second portions, said first portion extending through said housing and being manually moved by an operator to one of an engaged and a disengaged position, said second portion being located in said sump, said check valves being held open by said second portion in said first portion engaged position wherein fluid flow from said conduits to said sump through said check valves is facilitated, said second position being out of operative engagement with said valves in said first portion disengaged position wherein fluid flow from said conduits to said sump is prevented by said check valves, wherein said hydraulic bypass mechanism second portion is provided with first and second projections which are respectively moved into and out of engagement with said first and second check valves, wherein said hydraulic bypass mechanism second portion has a part which is fixed relative to said center block, and a part which is moveable relative to said center block, said second portion moveable part being elastically displaceable relative to said second portion fixed part, said first and second projections being located on said second portion moveable part. 26. The transmission of claim 25, wherein said hydraulic bypass mechanism first portion is manually moved by the operator through a linkage connected to said first portion.27. The transmission of claim 25, wherein said hydraulic bypass mechanism first portion comprises a rotating leg having an axis of rotation, said first portion being rotated about its said axis between its said engaged and disengaged positions.28. The transmission of claim 25, wherein said hydraulic bypass mechanism fruit portion is biased into its said disengaged position.29. The transmission of claim 25, wherein said hydraulic bypass mechanism first and second portions are separable elements.30. The transmission of claim 29, wherein said hydraulic bypass mechanism first portion is provided with a surface defining an edge, said hydraulic bypass mechanism second portion being displaced by said edge as said first portion is moved from its said disengaged position to its said engaged position.31. The transmission of claim 25, wherein said second portion comprises a resilient plate.32. The transmission of claim 25, wherein said second portion comprises a resilient wire.33. A hydrostatic transmission comprising:a housing partially defining a sump in which is provided hydrostatic fluid; an axial piston pump having a rotatable input shaft; an axial piston motor having a rotatable output shaft; a center block to which said pump and motor are rotatably connected, said pump and motor being hydraulically connected through first and second fluid conduits extending through said center block, said pump, motor and conduits defining a hydraulic circuit, said center block further having first and second check valves respectively located between said sump and said first and second conduits, hydrostatic fluid in said sump being automatically drawn into said hydraulic circuit through said valves; and a hydraulic bypass mechanism comprising a first portion operatively engaged with a unitary second portion, said first portion extending through said housing and being manually moved by an operator to one of an engaged and a disengaged position, said second portion being located in said sump, said check valves being held open by said second portion in said first portion engaged position wherein fluid flow from said conduits to said sump through said check valves is facilitated, said second portion being out of operative engagement with said valves in said first portion disengaged position wherein fluid flow from said conduits to said sump is prevented by said check valves, wherein said hydraulic bypass mechanism second portion is provided with first and second projections which are respectively moved into and out of engagement with said first and second check valves, wherein said hydraulic bypass mechanism second portion is a resilient plate having said first and second projections formed therein. 34. A hydrostatic transmission comprising:a housing partially defining a sump in which is provided hydrostatic fluid; an axial piston pump having a rotatable input shaft; an axial piston motor having a rotatable output shaft; a center block to which said pump and motor are rotatably connected, said pump and motor being hydraulically connected through first and second fluid conduits extending through said center block, said pump, motor and conduits defining a hydraulic circuit, said center block further having first and second check valves respectively located between said sump and said first and second conduits, hydrostatic fluid in said sump being automatically drawn into said hydraulic circuit through said valves; and a hydraulic bypass mechanism comprising operatively engaged first and second portions, said first portion extending through said housing and being manually moved by an operator to one of an engaged and a disengaged position, said second portion being located in said sump, said check valves being held open by said second portion in said first portion engaged position wherein fluid flow from said conduits to said sump through said check valves is facilitated, said second portion being out of operative engagement with said valves in said first portion disengaged position wherein fluid flow from said conduits to said sump is prevented by said check valves, wherein said hydraulic bypass mechanism second portion is provided with first and second projections which are respectively moved into and out of engagement with said first and second check valves, wherein said hydraulic bypass mechanism second portion is a resilient wire having said first and second projections formed therein. 35. A hydrostatic transmission comprising:a housing having walls at least partially defining a hydrostatic fluid-containing sump; a fluid circuit comprising a pump having a rotating input, a motor having a rotatable output, and a conduit through which said pump and motor are in fluid communication, said pump and motor being in operative fluid engagement via pressurized hydrostatic fluid in said conduit; a valve disposed between said conduit and said sump and having open and closed conditions, hydrostatic fluid in said conduit being permitted to flow from said conduit to said sump through said valve when said valve is in its said open condition whereby said pump and motor are placed out of operative fluid engagement, hydrostatic fluid in said conduit being prevented from flowing from said conduit to said sump through said valve when said valve is in its said closed condition whereby said pump and motor may be maintained in operative fluid engagement; and a hydraulic bypass mechanism comprising a manually-moved actuator portion extending through said housing, and a unitary, resilient actuated portion disposed in said housing and operatively engaged with said actuator portion and said valve, changes between said valve conditions being responsive to movement of said actuator portion, said mechanism being elastically biased into one of an engaged state wherein said valve is held in its said open condition by said actuated portion and a disengaged state wherein said valve is not held in its said open condition by said actuated portion. 36. The transmission of claim 35, wherein said actuated portion comprises a resilient plate.37. The transmission of claim 35, wherein said actuated portion comprises a resilient wire.