| 摘要 |
A hydrostatic transmission apparatus has a housing (3), a hydraulic pump (21) disposed in the housing (3) so as to be driven by a prime mover (14) and a first hydraulic motor (22) disposed in the housing (3). A first port (26b) is provided on the housing (3) and opens outward from the housing (3). A first fluid passage (30a) is disposed in the housing (3) and interposed between the hydraulic pump (21) and the first hydraulic motor (22). A second port (26a) is provided on the housing (3) and opens outward from the housing (3). A second fluid passage (30b) is disposed in the housing (3) and extended from the hydraulic pump (21) to the first port (26b), wherein the first and second ports (26b,26a) are adapted to be fluidly connected to a second hydraulic motor (24,25) disposed outside of the housing (3) so as to constitute a closed fluid circuit fluidly connecting the first and second hydraulic motors (22,24,25) in series to the hydraulic pump (21). A third fluid passage (30c) is disposed in the housing (3) and extends from the first hydraulic motor (22) to the second port (26a). The hydrostatic transmission apparatus also has a first bypass means (115,117,119,150a) for allowing fluid to bypass the hydraulic pump (21) between the first and second fluid passages (30a,30b) and a second bypass means (116,118,119,150b) for allowing fluid to bypass the first hydraulic motor (22) between the first and third fluid passages (30a,30c). |
