초록 ▼

A hydrostatic transmission is disclosed comprising a radial ball pump (11) and a radial ball motor (13) wherein the normal journal member (33) may be replaced by an alternative or modified journal member (33′), such that even with a reverse direction of actuation of the displacement control (49), th

A hydrostatic transmission is disclosed comprising a radial ball pump (11) and a radial ball motor (13) wherein the normal journal member (33) may be replaced by an alternative or modified journal member (33′), such that even with a reverse direction of actuation of the displacement control (49), the HST still operates in the forward direction, with no other changes required. The present invention also includes a simplified dump valve member (107) comprising a single, unitary member which may be merely inserted to its assembled position in which a pair of retention portions (123, 135) retain the dump valve, and permit it to pivot about the retention portions from an unactuated position to an actuated position.

대표청구항 ▼

A hydrostatic transmission comprising a housing assembly, a variable displacement radial piston pump and a fluid pressure operated motor disposed in said housing assembly; said radial piston pump including displacement varying means operable to vary the displacement of said pump, including reversibl

A hydrostatic transmission comprising a housing assembly, a variable displacement radial piston pump and a fluid pressure operated motor disposed in said housing assembly; said radial piston pump including displacement varying means operable to vary the displacement of said pump, including reversible control means operable to move said displacement varying means in first and second opposite directions, in response to movement of said control means in first and second opposite directions from a neutral position; said motor defining a fluid inlet and a fluid outlet, and said housing assembly defining high and low pressure passages in fluid communication with said fluid inlet and said fluid outlet, respectively; said pump comprises a rotor assembly rotatably mounted on a journal member disposed within a journal bore defined by said housing assembly, said journal bore providing open fluid communication with both of said high and low pressure passages; said journal member defining high and low pressure pump slots in fluid communication with contracting and expanding chambers, respectively, of said pump, said journal member further defining high and low pressure housing slots in fluid communication with said high and low pressure passages, respectively, and said journal member defining a high pressure axial bore interconnecting said high pressure pump and housing slots, and a low pressure axial bore interconnecting said low pressure pump and housing slots; characterized by: said journal member is an element selected from a group consisting of: (a) a first journal member in which said axial bores are oriented generally perpendicular to said pump slots, and said housing slots are oriented generally perpendicular to said axial bores, whereby said hydrostatic transmission operates in a forward direction in response to movement of said control means in said first direction from said neutral position; and, (b) a second journal member in which said axial bores are oriented at an acute angle relative to said pump slots and said housing slots are oriented at an acute angle relative to said axial bores whereby said hydrostatic transmission operates in said forward direction in response to movement of said control means in said second direction from said neutral position.