Abstract: A hydraulic motor assembly having a hydraulic motor mounted in a motor housing and an axle mounted in a separate axle housing. A ring gear and a port block are mounted between the motor housing and the axle housing. A swash plate is mounted in the motor housing and is engaged to the hydraulic motor to control the hydraulic output thereof, and the swash plate is movable between at least a first position and a second position.

Abstract: An electronic steering control system for controlling the lateral movement of a vehicle powered by a pair of hydrostatic drive devices, where the system controls a pair of actuators. Each actuator is configured to move a control member associated with one of the hydrostatic drive devices.

Abstract: A hydrostatic transmission assembly includes a first gerotor motor, a pump housing, a first variable displacement pump, a second gerotor motor, and a second variable displacement pump. The first gerotor motor includes a first output shaft aligned along a first axis. The pump housing connects to and contacts the first gerotor motor. The first variable displacement pump includes a first driven shaft mounted to the pump housing and aligned along a second axis, the second axis being generally perpendicular to the first axis (the first output shaft axis). The first variable displacement pump is in fluid communication with the first gerotor motor via passages in the pump housing. The second gerotor motor includes a second output shaft generally aligned along or generally parallel to the first axis. The second gerotor motor is connected to the pump housing on an opposite side of the pump housing as the first gerotor motor.

Abstract: An engine suitable for a motor vehicle, preferably a motorcycle, and a related transmission is provided. The transmission is provided with a hydrostatic device and a planetary transmission leading to a driven shaft. In order to optimize the engine with regard to construction and function the hydrostatic device of the transmission cooperating with the internal combustion engine is in an effective connection to the planetary transmission.

Abstract: A drive apparatus for a zero turn vehicle or similar application comprising a pair of pumps mounted in a common housing and having coaxial input shafts and a main input shaft mounted in the common housing perpendicular to the two pump shafts. A pair of center sections or end caps including hydraulic porting are mounted to opposite ends of the common housing, and each center section has a hydraulic motor mounted thereon external to the common housing. A power take off unit may also be mounted to the common housing and driven by the main input shaft.

Abstract: An axle driving unit includes a pair of axles, a differential unit for differently connecting the pair of axles to each other, a hydraulic pump, a hydraulic motor, a motor shaft, an output gear on said motor shaft for drivingly connecting to said differential unit, a center section having a pump mounting surface and a motor mounting surface onto which said hydraulic pump and the hydraulic motor are mounted respectively, a housing constituted by a first housing part and a second housing part joined to each other at a joint surface, and a fastener fastening the center section to the first housing part. The center section is entirely disposed in the first housing part, whereby the hydraulic pump, the hydraulic motor and the output gear are entirely contained in the first housing part. The motor mounting surface may be disposed in parallel to the joint surface of the housing.

Abstract: A hydraulic transaxle including: a variable displacement hydraulic motor with a movable swash plate whose tilt angle defines a displacement of the hydraulic motor; a casing incorporating the hydraulic motor; and a mechanism for determining a range of the tilt angle of the swash plate, wherein the mechanism can fix the tilt angle of the swash plate so as to set the hydraulic motor in a fixed displacement type. A vehicle includes the transaxles for driving respective axles wherein each of the transaxles can select whether the displacement of its hydraulic motor is variable or fixed.

Abstract: A hydraulic drive device including a center section for rotatably mounting a hydraulic pump and hydraulic motor on respective running surfaces. The center section further includes a pair of ports connecting the running surfaces, where the ports are not located in the same plane but are rather offset from one another with respect to the pump running surface, so that one of the ports is closer to the pump running surface than the other port.

Abstract: To provide a short connection hydraulic path structure with a sufficiently large diameter to adequately lower the pressure in a high-pressure hydraulic path while the clutch is off, in a static hydraulic continuously variable transmission for sliding a clutch valve installed within the transmission shaft, to change the power being transmitted and shorten the high-pressure hydraulic path and low-pressure hydraulic path. A high-pressure fluid path is provided for sending hydraulic fluid from the hydraulic pump side to the hydraulic motor side with a low-pressure fluid path for sending hydraulic fluid from the hydraulic motor side to the hydraulic pump side. A hydraulic circuit includes a switching valve for switching the plungers to the high-pressure path or the low-pressure path as a dual structure within a valve body between the hydraulic pump made from multiple plungers, and a hydraulic motor made from multiple motors.

Abstract: An embodiment of the present invention involves a zero turn drive apparatus. The zero turn drive apparatus has a housing, which has a first and a second end. The housing has a first end cap mounted on the first end of the housing, and a second end cap mounted on the second end of the housing. A hydraulic pump is rotatably mounted on each end cap, and each hydraulic pump is driven by a pump input shaft. A gear chamber is interposed between each pump. A power take off mechanism is engaged to the housing, and an output shaft extends from the power take off mechanism. An input shaft, which is engaged to each of the pump input shafts, extends into the power take off mechanism and is selectively engaged to the output shaft.

Abstract: A hydraulic differential with a variable displacement hydraulic unit of the axial piston type, a fixed displacement hydraulic unit of the axial piston type, a stationary housing for mounting the hydraulic units, an input shaft for coupling to a variable speed power source and an output shaft for coupling to a constant speed load, comprises: a wobbler and a port plate for the variable displacement hydraulic unit coupled to the stationary housing; an axial block and piston set for the variable displacement hydraulic unit, a port plate for the fixed displacement hydraulic unit and a wobbler for the fixed displacement hydraulic unit coupled to the input shaft; and an axial block and piston set for the fixed displacement hydraulic unit coupled to the output shaft; wherein the variable displacement hydraulic unit port plate and the fixed displacement hydraulic unit port plate couple together through a circumferential interface to minimise hydraulic thrust forces developed by the hydraulic unit.

Abstract: A bypass mechanism for a hydraulic apparatus is provided, where a rotatable hydraulic component such as a motor cylinder block is disposed on a running surface and in fluid communication with a closed hydraulic circuit. The hydraulic component is drivingly engaged to a shaft, such as a motor shaft. An arm or similar mechanism is engaged to the shaft to move it from a standard operating position to a second position where the shaft engages the hydraulic component to lift the component off its running surface, thereby placing the hydraulic apparatus into bypass by opening the closed hydraulic circuit to a sump.

Abstract: An improved differential unit for an integrated hydrostatic transmission (IHT) is provided. The differential unit comprises an input gear, a cross-shaft disposed within a central opening of the input gear, and a pair of clutch members disposed coaxial with the input gear. One of each clutch member is disposed on opposite sides of the cross-shaft. A first plurality of friction members extend from each clutch member. The differential unit also comprises a pair of side couplings, each coaxially disposed within one of the clutch members, and a second plurality of friction members extending from each side coupling. Each clutch member includes a cam surface that comes in contact with the cross-shaft when the differential unit is under normal operating conditions. Alternative embodiments are also described herein.

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: A control mechanism for a hydraulic drive apparatus such as a transaxle having a hydraulic pump and moveable swash plate mounted in a housing including a control arm for moving the swash plate between forward and reverse positions and a unidirectional return to neutral mechanism for biasing and returning the swash plate to a neutral position when the control arm is in one of the reverse or forward positions but not from the other position.

Abstract: A flywheel 2 and an HST unit 5 are accommodated in a flywheel housing 13 of a working vehicle, the HST unit 5 comprising an oil hydraulic motor 9, an oil hydraulic pump 10, an oil hydraulic circuit block 17 containing an oil hydraulic circuit therein and supporting one end of an oil hydraulic motor shaft and one end of an oil hydraulic pump shaft, and a cover housing 18 secured to the oil hydraulic circuit block to cover the oil hydraulic motor and the oil hydraulic pump and support the other end of the oil hydraulic motor shaft and the other end of the oil hydraulic pump shaft; the oil hydraulic circuit block 17 being secured to an intermediate housing connected to the flywheel housing 13.

Abstract: With regard to a transaxle comprising a housing, which houses a hydrostatic stepless transmission constructed by fluidly connecting a hydraulic pump with a hydraulic motor and an axle drivingly connected to the transmission, the housing is constructed by detachably joining a first housing element with a second housing element through a joint surface in parallel to the lengthwise direction of the axle, a counter shaft, drivingly interposed between the hydrostatic stepless transmission and the axle in the housing, is located its axis in the first housing element, a leg member is engaged with the first housing element, and one of ends of the leg member is engaged with a part of the counter shaft, and the other end of the leg member is engaged with the second housing element so as not to be movable.

Abstract: A transaxle comprised of a hydrostatic transmission mounted in a transmission housing and having a pair of hydraulic pumps and hydraulic motors operatively connected together through a center section mounted in the housing. First and second axle housings are mounted on opposite ends of the transmission housing, with output axles mounted in the axle housings and connected to the respective hydraulic motors.

Abstract: A system for operating a hydromechanical transmission having a movable input member that transmits a signal to a control unit that uses predefined logic to determine if a hydrostatic transmission should be in a first low speed mode that uses displacement control or if it should be in a second high speed mode that uses a power, torque, or speed control scheme.

Abstract: A control assembly for use with hydraulic apparatus having a housing, a trunnion extending from the housing, a return arm and a control arm mounted on the trunnion. The control assembly is attached to the trunnion arm and includes a pair of scissor return arms biased to place the hydraulic apparatus in a neutral condition, a pair of bushings and a spacer pressed into the bushings to form the assembly.

Abstract: A hydraulic drive apparatus having an actuator assembly mounted on a control device is disclosed. The hydraulic drive apparatus comprises an input, a hydraulic pump, a control device, and an actuator assembly. The hydraulic drive apparatus is mounted on a vehicle that comprises an operating system. A prime mover drives the input, which subsequently drives one or more axle shafts. The transmission is capable of operation in forward and reverse directions. The control device determines the direction of operation and speed of the transmission. The actuator assembly is mounted to a component of the control device. The actuator assembly determines the state of operation of the output device with respect to the forward or reverse operation of the transmission.

Abstract: A hydrostatic transmission on a tractor is operated by a microcontroller providing current commands to the hydrostatic transmission pump, and manual controls that provide signals to the microcontroller so the current commands cause the hydrostatic transmission to operate in either a first mode or a second mode. In the first or automatic mode the swash plate position may be continuously variable based on the position of a foot pedal. In the second or gear mode the swash plate may be moved to any of a plurality of discrete positions based on the position of a manually operable switch.

Abstract: A pull testing mechanism. A first fixed member and a second fixed member are disposed on a base and oppose each other. A first movable member and a second movable member are movably connected to the first and second fixed members, respectively. A first rotating member includes a first rod, a second rod, and a first hook. The first rod is connected to the first movable member and second rod. The second rod abuts the first fixed member. The first hook is connected to the second rod and under the base. A second rotating member includes a third rod, a fourth rod, and a second hook. The third rod is connected to the second movable member and fourth rod. The fourth rod abuts the second fixed member. The second hook is connected to the fourth rod. A third movable member movably abuts between the first and second movable members.

Abstract: A hydraulic motor assembly having a hydraulic motor mounted in a motor housing and an axle mounted in a separate axle housing. A ring gear and a port block are mounted between the motor housing and the axle housing. A swash plate is mounted in the motor housing and is engaged to the hydraulic motor to control the hydraulic output thereof, and the swash plate is movable between at least a first position and a second position.

Abstract: A hydrostatic transaxle comprises: a motor casing; at least one hydraulic motor disposed in the motor casing; at least one output shaft disposed in the motor casing so as to be driven by the at least one hydraulic motor; and a pair of steerable wheel support units attached onto respective opposite ends of the motor casing. Each of the steerable wheel support units includes an axle, a steerable casing, a wheel, and a steering arm. In each of the steerable wheel support units, the axle is drivingly connected to the at least one output shaft, the steerable casing is substantially horizontally rotatable relative to the motor casing, the wheel is attached on an outer end of the axle outside of the steerable casing, and the steering arm is rotatably integrally provided on the steerable casing.

Abstract: A system and method for electronically controlling the displacement of hydraulic pumps, transmissions or transaxles. A moveable swash plate is cooperable with a rotatable hydraulic pump for controlling the output thereof, and a rotatable trunnion arm is coupled to the moveable swash plate. A pair of switches may be mounted in separate locations to detect the position of a control arm used to rotate the trunnion arm. The control arm may be connected to an electronic actuation drive used to electronically control the rotatable control arm.

Abstract: A flywheel housing is partitioned by a partition wall disposed at an intermediate position in the lengthwise direction thereof to form a pair of housing portions in which a flywheel is accommodated in one housing portion, and an HST unit that receives power from the flywheel is installed in the other housing portion, the HST unit comprising an oil hydraulic motor, an oil hydraulic pump, an oil hydraulic circuit block containing an oil hydraulic circuit therein and supporting one end of an oil hydraulic motor shaft and one end of an oil hydraulic pump shaft, and a cover housing secured to the oil hydraulic circuit block to cover the oil hydraulic motor and the oil hydraulic pump and support the other end of the oil hydraulic motor shaft and the other end of the oil hydraulic pump shaft; the oil hydraulic circuit block being secured to the flywheel housing.

Abstract: The present invention makes it possible, in an HST drive circuit wherein an HST pump and an HST motor have been separately stored in a pump case and a motor case, to efficiently cool the HST drive circuit. A cooling line for, while discharging a relief oil from a charge circuit 9 for replenishing an HST closed circuit 5 with a pressure oil into a pump case 3, making the discharged oil flow into a reservoir 7 through the pump case 3, a communicating pipe 14, a motor case 4, and an oil cooler 16 is formed, so that hydraulic oil circulating through an HST pump 1, an HST motor 2, and the HST closed circuit 5 is cooled by an oil flowing through the cooling line.

Abstract: There is provided an HST in which a hydraulic pump unit operatively driven by a driving power source and a hydraulic motor unit arranged spaced apart from the hydraulic pump unit and operatively driving a driving-wheel are fluidly connected by way of operation fluid lines so as to form a closed circuit; wherein the hydraulic motor unit is provided with motor-side operation fluid passages forming one part of the operation fluid lines; a motor-side charge fluid passage having a first end opened to an outside to form a motor-side charge port and a second end fluidly connected to at lease one of the motor-side operation fluid passages; and a check valve interposed in the motor-side charge fluid passage so as to allow the fluid to flow from the motor-side charge port to the one motor-side operation fluid passage while preventing the reverse flow.

Abstract: A control arm is coupled to a control shaft of a hydraulic pump. A friction shaft extends parallel to the control shaft and is slidably moveable within an arcuate-shaped hole in the control arm. A stop plate is movably supported by the control shaft and the friction shaft. When the stop plate is in the operating position, a friction pad supported by the friction shaft is biased by a pressure plate and a spring against the control arm. When the stop plate is in the braking position, a sloping region of the stop plate engages a pin extending from the pressure plate such that the friction pad is spaced from the control arm and arcuate-shaped grooves in the stop plate engage pins extending from the control arm in a neutral position. The present invention also includes a hydrostatic transmission and a vehicle incorporating the cruise control and neutral return mechanism.

Abstract: An improved diagnostic system for a hydrostatic apparatus such as a hydrostatic transmission or transaxle is disclosed. A fastener having a port formed therein is used to connect a hydraulic component such as a center section to a housing. A diagnostic system may be located external to the housing and connected to the hydraulic circuit at least partially through the fastener port. A relief valve may also be located in the fastener and connected to the fastener port, or in a different fastener having a separate fastener port, to permit the fluid in the hydraulic circuit to be discharged to a sump.

Abstract: An integrated hydraulic transaxle (IHT) comprises a hydrostatic transmission (HST), an axle driven by the HST, and a housing incorporating the HST and the axle. The HST includes a variable displacement hydraulic pump driven by a prime mover, and a hydraulic motor fluidly connected to the hydraulic pump. The hydraulic pump has a trunnion type movable swash plate. The internal displacement of the hydraulic motor is larger than the internal displacement of the hydraulic pump so as to increase the hydraulic deceleration activity of the HST. In the IHT, a mechanical deceleration drive train is interposed between the hydraulic motor and the axle. The mechanical deceleration activity of the mechanical deceleration drive train is reduced so far as the increase of the hydraulic deceleration activity of the HST.

Abstract: An electronic steering control system for controlling the lateral movement of a vehicle powered by a pair of hydrostatic drive devices, where the system controls a pair of actuators. Each actuator is configured to move a control member associated with one of the hydrostatic drive devices.

Abstract: There is provided a pump unit configured to be capable of transmitting a rotational power from a driving power source which is operatively connected thereto to an actuator through a pair of hydraulic fluid lines. The pump unit includes: an input shaft; a hydraulic pump main body; a PTO shaft; a PTO clutch mechanism; an auxiliary pump main body; a suction line; a discharge line; a charge line; a PTO hydraulic fluid line; a pressure-reducing valve; and a resistance valve. The PTO hydraulic fluid line and the charge line are fluidly connected to the primary side and a secondary side of the pressure-reducing valve, respectively.

Abstract: An axle driving apparatus comprises: a common housing; a pair of coaxial axles disposed in the housing; a common input shaft for receiving power from a prime mover, the common input shaft being extended perpendicular to the axles in the housing and passed through a gap between the axles; and a pair of stepless transmissions sharing power from the common input shaft, and transmitting power to the respective axles. The pair of stepless transmissions are arranged in the housing symmetrically centered on an axis of the common input shaft. The axle driving apparatus further comprises: a PTO shaft disposed coaxially to the common input shaft; a clutch disposed in the housing and interposed between the common input shaft and the PTO shaft; and a brake which is applied simultaneously to disengagement of said clutch so as to prevent inertial rotation of said PTO shaft.

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: A hydrostatic continuously variable transmission comprises: a hydraulic pump; a power input shaft engaged with the hydraulic pump to transmit power from a power source to the hydraulic pump; a hydraulic motor in hydraulic communication with the hydraulic pump; a casing that houses the hydraulic pump and the hydraulic motor; a port block mounted to the casing, the port block having a block main body and a cover member connected to a power input side of the block main body, said cover member having an outer surface; a cooling hydraulic path provided in the port block in a region where the block main body and the cover member meet, the cooling hydraulic path being connected to a first hydraulic path in the port block, the cooling hydraulic path having a plurality of bends; a cooling fan provided on the power input shaft to provide air flow directly to the outer surface of the cover member.

Abstract: A hydrostatic transaxle apparatus comprises a housing in which an HST, a pair of axles, a differential unit differentially connecting the axles to each other, and a horizontal counter shaft interposed between the HST and the differential unit. The HST comprises axial piston type hydraulic pump and motor mounted on vertically opposite surfaces of a center section, respectively, so as to be fluidly connected to each other so that pump and motor shafts are disposed vertically coaxially to each other. The center section is disposed adjacently to the differential unit and one of the axles. A cooling fan is fixed on the pump shaft projecting outward from the housing. When along the pump shaft, most of the housing except portions thereof for housing the respective axles is disposed within an area of rotary locus of the cooling fan.

Abstract: A hydrostatic transmission vehicle comprises: a fuel adjustment position detection portion (681) which detects an operation position of a fuel adjustment portion (68); a deceleration operation position detection portion (691) which detects an operation quantity of a deceleration operation portion (69); and a controller (9) which controls a displacement of a hydrostatic transmission (7), and the controller (9) comprises: an operation state judgment portion (91) which judges operation states of the fuel adjustment portion (68) and the deceleration operation portion (69) based on detection values acquired by the fuel adjustment position detection portion (681) and the deceleration operation position detection portion (691); and a displacement control command generation portion (94) which generates a displacement control command which differs depending on a case where an engine revolution number is restricted by the fuel adjustment portion (68) and a case where an engine revolution number is restricted by the dec

Abstract: An expansion sump is provided in the axle horn of a hydraulic apparatus, and a cap member seals the expansion sump from the main sump. An arcuate sealed fluid passage is provided between the periphery of the cap member and the housing. The sealed fluid passage cooperates with a first passage between the expansion sump and the sealed fluid passage and a second passage between the main sump and the sealed fluid passage to form a siphon to permit fluid communication between the two sumps. The hydraulic apparatus may also have an oil filter removably mounted on the external surface of the housing and a removable shield adjacent thereto, with an engagement member formed on the shield to prevent the oil filter from being removed from the housing with the shield in place.

Abstract: A control assembly for use with hydraulic apparatus having a housing, a trunnion extending from the housing, a return arm and a control arm mounted on the trunnion. The control assembly is attached to the trunnion arm and includes a pair of scissor return arms biased to place the hydraulic apparatus in a neutral condition, a pair of bushings and a spacer pressed into the bushings to form the assembly.

Abstract: The invention concerns a method and a hydromachine with a commutation device and with expanding and contracting pressure chambers passed by fluid and formed by displacement arrangements. With the method and the hydromachine, it is endeavoured to control a displacement in the hydromachine to keep pressure fluctuations small. For this purpose, the hydromachine has a group of devices, comprising a commutation device and at least two displacement devices, at least two of the devices being adjusted in relation to each other.

Abstract: Disclosed is a vehicle comprising a transaxle and a bypass mechanism. The transaxle has a plurality of mounting holes for use in attaching the transaxle to the vehicle. Further, the transaxle has at least one mounting hole more than is used to attach the transaxle to the vehicle. The bypass mechanism comprises a bypass linkage. Finally, the bypass linkage is supported by the mounting hole.

Abstract: A flywheel housing 13 is partitioned by a partition wall 14 disposed at an intermediate position in the lengthwise direction thereof to form a pair of housing portions in which a flywheel 13 is accommodated in one housing portion 13X, and an HST unit that receives power from the flywheel is installed in the other housing portion 13Y, the HST unit 5 comprising an oil hydraulic motor 9, an oil hydraulic pump 10, an oil hydraulic circuit block 17 containing an oil hydraulic circuit therein and supporting one end of an oil hydraulic motor shaft and one end of an oil hydraulic pump shaft, and a cover housing 18 secured to the oil hydraulic circuit block to cover the oil hydraulic motor and the oil hydraulic pump and support the other end of the oil hydraulic motor shaft and the other end of the oil hydraulic pump shaft; the oil hydraulic circuit block 17 being secured to the flywheel housing.

Abstract: A steering system for a work machine having a hydrostatic transmission is disclosed. The steering system has a primary source of pressurized fluid and a steering control valve. The steering system also has a first fluid passageway fluidly connecting the primary source of pressurized fluid to the steering control valve and a second fluid passageway fluidly connecting the hydrostatic transmission to the steering control valve.

Abstract: A system and method for electronically controlling the displacement of hydraulic pumps, transmissions or transaxles. A moveable swash plate is cooperable with a rotatable hydraulic pump for controlling the output thereof, and a rotatable trunnion arm is coupled to the moveable swash plate. A pair of switches may be mounted in separate locations to detect the position of a control arm used to rotate the trunnion arm. The control arm may be connected to an electronic actuation drive used to electronically control the rotatable control arm.

Abstract: A hydrostatic module is disclosed, including a pair of shafts rotatably supported by a frame. Two yokes are pivotally mounted on the frame, each having complimentary surfaces to the other yoke and to the frame, minimizing the space occupied by the yokes. Stop means are provided on the yokes and on the frame to limit the pivotal movement of the yokes. A hydrostatic power unit is carried by each yoke, each connected to one of the shafts. A control system, having a single piece control housing containing servo pistons, pivots the yokes. The servo pistons independently determine the orientation of the yokes. A single piece fluid control porting plate is secured to the control housing to route hydraulic fluid to multiple locations within the control housing. A fluid manifold serves as a main structural element, with intimate proximity between the manifold and the control housing allowing simplified fluid exchange therebetween.

Abstract: A power unit includes an engine and a static hydraulic continuously variable transmission with a swash plate type hydraulic pump and a hydraulic motor, which are connected via a hydraulic pressure closing circuit. This power unit drives the hydraulic pump to rotate with the engine and performs swash plate angle control of the hydraulic motor. A crankshaft mechanism of the engine and a rotating mechanism of the static hydraulic continuously variable transmission are housed in a transmission housing. A cylinder of the engine is integrated with the transmission housing, and a swash plate control motor for swash plate angle control of the hydraulic motor is positioned at an area adjacent a root of the cylinder in the transmission housing.

Abstract: An embodiment of the present invention involves a zero turn drive apparatus. The zero turn drive apparatus has a housing, which has a first and a second end. The housing has a first end cap mounted on the first end of the housing, and a second end cap mounted on the second end of the housing. A hydraulic pump is rotatably mounted on each end cap, and each hydraulic pump is driven by a pump input shaft. A gear chamber is interposed between each pump. A power take off mechanism is engaged to the housing, and an output shaft extends from the power take off mechanism. An input shaft, which is engaged to each of the pump input shafts, extends into the power take off mechanism and is selectively engaged to the output shaft.

Abstract: An axle driving apparatus comprises: a common housing; a pair of coaxial axles disposed in the housing; a common input shaft for receiving power from a prime mover, the common input shaft being extended perpendicular to the axles in the housing and passed through a gap between the axles; and a pair of stepless transmissions sharing power from the common input shaft, and transmitting power to the respective axles. The pair of stepless transmissions are arranged in the housing symmetrically centered on an axis of the common input shaft. The axle driving apparatus further comprises: a PTO shaft disposed coaxially to the common input shaft; a clutch disposed in the housing and interposed between the common input shaft and the PTO shaft; and a brake which is applied simultaneously to disengagement of said clutch so as to prevent inertial rotation of said PTO shaft.