Abstract: A power transmission system for a working vehicle comprises: a vehicle frame; a prime mover mounted on the vehicle frame; a pair of left and right drive wheels; a pair of left and right transaxles juxtaposed on the vehicle frame, wherein each of the left and right transaxles includes a single axle for individually driving each of the left and right drive wheels in forward and rearward directions; a working device; and a working power clutch unit disposed between the left and right transaxles so as to clutch on/off power transmitted from the prime mover to the working device.

Abstract: A transaxle apparatus comprises: a housing; a hydrostatic transmission disposed in the housing, the hydrostatic transmission including a hydraulic pump receiving power from a prime mover, a first hydraulic motor driven in response to fluid supplied from the hydraulic pump, and a center section including an inner fluid passage for fluidly connecting the first hydraulic motor to the hydraulic pump; a first axle disposed in the housing and driven by the first hydraulic motor; a hydraulic actuator disposed outside the housing so as to drive a second axle disposed outside the housing; a port opened outside the housing so as to be fluidly connected to the hydraulic actuator; and a block interposed between the center section and the port in the housing, wherein a fluid passage is disposed in the block so as to connect the port to the inner fluid passage in the center section.

Abstract: The present invention provides a tandem pump unit that includes: a first hydraulic pump and a second hydraulic pump respectively having a first pump shaft and a second pump shaft respectively having adjacent ends connected together so that the first and second pump shafts are coaxially aligned and non-rotatably connected in tandem; a common housing for accommodating the first hydraulic pump and the second hydraulic pump; and a first center section and a second center section that respectively support the first and second hydraulic pumps.

Abstract: An axle driving system which houses in a housing thereof a hydrostatic transmission, axles, and a driving gear train for connecting output means of the hydraulic transmission and axles, so as to transmit power from a driving source to the hydrostatic transmission and to change the speed, thereby driving the axles. A first chamber therein contains the hydrostatic transmission and a second chamber therein contains the driving gear train. Both the first and second chambers are independent of each other so as to prevent a foreign object, such as iron powder produced in the driving gear train, from entering the hydrostatic transmission. The system includes an L-like-shaped center section on which the hydrostatic transmission is offset such that an imaginary plane which includes a motor mounting surface passes in proximity to the axis of a pump shaft. The pump shaft is disposed perpendicular to the axles. The motor shaft is disposed in parallel thereto.

Abstract: An axle driving apparatus comprising a common housing in which a hydraulic pump and a hydraulic motor fluidly connected with each other and an axle driven by the hydraulic motor are disposed, At least one of the hydraulic pump and the hydraulic motor is variable in displacement and has a capacity changing device for changing its capacity. A hydraulic actuator is provided in the housing for controlling the capacity changing device. A control valve for hydraulically controlling the hydraulic actuator is provided in the housing. A center section for fluidly connecting the hydraulic pump and the hydraulic motor with each other is fixedly disposed in the housing and a driving part of the hydraulic actuator and the control valve are incorporated in the center section. A rotary member operatively connected to a human-operated traveling control member provided on a vehicle is rotatably supported by the housing.

Abstract: An axle driving apparatus in which a hydraulic pump and a hydraulic motor which constitute a hydrostatic transmission are disposed on a center section. In a horizontal portion of the center section are provided a pair of linear oil passages in parallel to each other. A pair of arcuate ports are provided on a pump mounting surface formed on the horizontal portion of the center section. The pair of arcuate ports are substantially perpendicular with respect to the direction in which the oil passages extend. The axis of slanting movement of a movable swash plate of the hydraulic pump extends laterally of the vehicle body on which the axle driving apparatus is provided. The rotating direction of an arm provided on a control shaft for slantingly operating the movable swash plate is coincident with the operating direction of a control rod connected with a speed changing member. Thus, the link mechanism for connecting the speed changing member and the control arm for the movable swash plate is simplified.

Abstract: The present invention provides a pump unit including at least one hydraulic pump with inlet and outlet ports, a pump case for accommodating the hydraulic pump having an opening through which the hydraulic pump is insertable, and a lid, called a center section, closing the pump case. The center section forms a pair of inlet/outlet passages communicating an end with the inlet and outlet ports of the hydraulic pump and an end opening through a pump case abutting surface of the center section, and a first charging passage by which hydraulic fluid is fed through the pump case abutting surface of the center section. At least one of the pump case and the center section communicates the first charging passage with the pair of inlet/outlet passages via a first hydraulic fluid feeding valve preventing the reverse flow into said first charging passage.

Abstract: An axle driving apparatus for being mounted on the body frame of a vehicle and for independently rotating drive wheel members. The axle driving apparatus includes a first axle driving unit (18L) having a housing (40) and a single axle (20L), the single axle (20L) defining a proximal end portion rotatably mounted in the housing (40) and a distal end portion extending outwardly from a first side of the housing (40). An enlarged region is defined by the housing (40), with the enlarged region extending substantially perpendicular to the longitudinal axis of the single axle (20L). A hydraulic stepless speed change assembly (22) is disposed within the enlarged region. The speed change assembly (22) includes a hydraulic pump (52) having an input shaft (21) projecting from the enlarged region and includes a hydraulic motor (55) including an output shaft (74) drivingly connected to the single axle (20L).

Abstract: There is provided an HST unit including: a first hydraulic motor unit for operatively driving one of a pair of driving wheels; a second hydraulic motor unit for operatively driving the other one of the pair of driving wheels; a hydraulic pump unit operatively connected to a driving power source, the hydraulic pump unit configuring a traveling hydrostatic transmission in cooperation with the first and second hydraulic motor units; and an attachment frame for supporting the first hydraulic motor unit, the second hydraulic motor unit and the hydraulic pump unit, the attachment frame being attachable to a vehicle frame.

Abstract: A vehicle includes a first transaxle incorporating a first hydraulic motor for driving a first axle, a pair of second transaxles incorporating respective second hydraulic motors for driving respective second axles, and a pump housing separated from the first transaxle and the pair of second transaxles. The pump housing incorporates a hydraulic pump. The first hydraulic motor and the pair of second hydraulic motors are fluidly connected in series to the hydraulic pump. The second hydraulic motors are fluidly connected in parallel to the hydraulic pump.

Abstract: There is provided a hydraulic pump unit of variable displacement type disposed away from a pair of hydraulic motor units which are capable of being independently arranged, the pump unit fluid-connected to the pair of hydraulic motor units so as to change the outputs of the pair of hydraulic motor units in both forward and reverse rotation directions. The pump unit includes a hydraulic pump body operatively rotated and driven by a driving source, a pump case surrounding the hydraulic pump body, a capacity adjusting mechanism for changing the capacity of the hydraulic pump body, and an actuator for operating the capacity adjusting mechanism. The actuator is controlled based on a manual operation signal corresponding to a manual operation amount.

Abstract: The present invention provides a pump unit including at least one hydraulic pump with inlet and outlet ports, a pump case for accommodating the hydraulic pump having an opening through which the hydraulic pump is insertable, and a lid, called a center section, closing the pump case. The center section forms a pair of inlet/outlet passages communicating an end with the inlet and outlet ports of the hydraulic pump and an end opening through a pump case abutting surface of the center section, and a first charging passage by which hydraulic fluid is fed through the pump case abutting surface of the center section. At least one of the pump case and the center section communicates the first charging passage with the pair of inlet/outlet passages via a first hydraulic fluid feeding valve preventing the reverse flow into said first charging passage.

Abstract: A transaxte apparatus for a four-wheel drive vehicle, comprises: a hydraulic pump; a housing; a hydraulic motor disposed in the housing so as to be driven in response to fluid from the hydraulic pump; an axle extended outward from the housing; a drive train disposed in the housing so as to drivingly connect the hydraulic motor to the axle; and a power take-off shaft disposed in the housing perpendicularly to a rotary axis of the hydraulic motor so as to be drivingly connected to the drive train and extended outward from the housing.

Abstract: The present invention provides a pump unit including at least one hydraulic pump with inlet and outlet ports, a pump case for accommodating the hydraulic pump having an opening through which the hydraulic pump is insertable, and a lid, called a center section, closing the pump case. The center section forms a pair of inlet/outlet passages communicating an end with the inlet and outlet ports of the hydraulic pump and an end opening through a pump case abutting surface of the center section, and a first charging passage by which hydraulic fluid is fed through the pump case abutting surface of the center section. At least one of the pump case and the center section communicates the first charging passage with the pair of inlet/outlet passages via a first hydraulic fluid feeding valve preventing the reverse flow into said first charging passage.

Abstract: There is provided a hydraulic pump unit of variable displacement type disposed away from a pair of hydraulic motor units which are capable of being independently arranged, the pump unit fluid-connected to the pair of hydraulic motor units so as to change the outputs of the pair of hydraulic motor units in both forward and reverse rotation directions. The pump unit includes a hydraulic pump body operatively rotated and driven by a driving source, a pump case surrounding the hydraulic pump body, a capacity adjusting mechanism for changing the capacity of the hydraulic pump body, and a hydraulic servomechanism for transmitting an external input based on a manual operation to the capacity adjusting mechanism by utilizing a hydraulic force.

Abstract: An axle driving system which houses in a housing thereof a hydrostatic transmission, axles, and a driving gear train for connecting output means of the hydraulic transmission and axles, so as to transmit power from a driving source to the hydrostatic transmission and to change the speed, thereby driving the axles. A first chamber therein contains the hydrostatic transmission and a second chamber therein contains the driving gear train. Both the first and second chambers are independent of each other so as to prevent a foreign object, such as iron powder produced in the driving gear train, from entering the hydrostatic transmission. The system includes an L-like-shaped center section on which the hydrostatic transmission is offset such that an imaginary plane which includes a motor mounting surface passes in proximity to the axis of a pump shaft. The pump shaft is disposed perpendicular to the axles. The motor shaft is disposed in parallel thereto.

Abstract: An axle driving apparatus comprising a common housing in which a hydraulic pump and a hydraulic motor fluidly connected with each other and an axle driven by the hydraulic motor are disposed, At least one of the hydraulic pump and the hydraulic motor is variable in displacement and has a capacity changing device for changing its capacity. A hydraulic actuator is provided in the housing for controlling the capacity changing device. A control valve for hydraulically controlling the hydraulic actuator is provided in the housing. A center section for fluidly connecting the hydraulic pump and the hydraulic motor with each other is fixedly disposed in the housing and a driving part of the hydraulic actuator and the control valve are incorporated in the center section. A rotary member operatively connected to a human-operated traveling control member provided on a vehicle is rotatably supported by the housing.

Abstract: An axle driving apparatus for being mounted on the body frame of a vehicle and for independently rotating drive wheel members. The axle driving apparatus includes a first axle driving unit (18L) having a housing (40) and a single axle (20L), the single axle (20L) defining a proximal end portion rotatably mounted in the housing (40) and a distal end portion extending outwardly from a first side of the housing (40). An enlarged region is defined by the housing (40), with the enlarged region extending substantially perpendicular to the longitudinal axis of the single axle (20L). A hydraulic stepless speed change assembly (22) is disposed within the enlarged region. The speed change assembly (22) includes a hydraulic pump (52) having an input shaft (21) projecting from the enlarged region and includes a hydraulic motor (55) including an output shaft (74) drivingly connected to the single axle (20L).

Abstract: The present invention provides a pump unit including at least one hydraulic pump with inlet and outlet ports, a pump case for accommodating the hydraulic pump having an opening through which the hydraulic pump is insertable, and a lid, called a center section, closing the pump case. The center section forms a pair of inlet/outlet passages communicating an end with the inlet and outlet ports of the hydraulic pump and an end opening through a pump case abutting surface of the center section, and a first charging passage by which hydraulic fluid is fed through the pump case abutting surface of the center section. At least one of the pump case and the center section communicates the first charging passage with the pair of inlet/outlet passages via a first hydraulic fluid feeding valve preventing the reverse flow into said first charging passage.

Abstract: An axle driving apparatus in which a hydraulic pump and a hydraulic motor which constitute a hydrostatic transmission are disposed on a center section. In a horizontal portion of the center section are provided a pair of linear oil passages in parallel to each other. A pair of arcuate ports are provided on a pump mounting surface formed on the horizontal portion of the center section. The pair of arcuate ports are substantially perpendicular with respect to the direction in which the oil passages extend. The axis of slanting movement of a movable swash plate of the hydraulic pump extends laterally of the vehicle body on which the axle driving apparatus is provided. The rotating direction of an arm provided on a control shaft for slantingly operating the movable swash plate is coincident with the operating direction of a control rod connected with a speed changing member. Thus, the link mechanism for connecting the speed changing member and the control arm for the movable swash plate is simplified.