Abstract: A hydrostatic transmission implements a braking system, in which at least one adjustable traction motor acting as a pump is supported via a closed circuit on an adjustable axial piston machine acting as a motor, which in turn is supported on an internal combustion engine. Since the internal combustion engine should not be rotated at excessive revolution rates, a control unit adjusts the swivel angle of the axial piston machine during braking. The axial piston machine is load-sensitive, as a relationship between the control pressure and the revolution rate and the pivot angle of the machine consists of a pressure difference between the two working lines of the closed circuit. Using a pre-control, a swivel angle of the axial piston machine is set during braking, and the swivel angle is corrected by a revolution rate controller, such that a target revolution rate is obtained on the combustion engine.

Abstract: A hydrostatic transmission is configured to realize a braking operation in which at least one adjustable traction motor, which acts as a pump, is supported via a closed circuit on an adjustable axial piston pump, which acts as a motor, and which in turn is supported on an internal combustion engine. Since overspeeding of the latter should be avoided, a control unit adjusts the pivot angle of the pump in accordance with a characteristic map which represents a relationship between a setting force and a pressure difference of two working lines of a closed circuit, a pump rotational speed, and the pivot angle. Thus, characteristic-map-based pilot control of the pivot angle of the pump is possible and feedback of the present pivot angle is omitted.

Abstract: A vehicle transaxle system includes a pair of right and left transaxle units equipped on a vehicle. The right transaxle unit supports a single right axle, and the left transaxle unit supports a single left axle. A variable displacement hydraulic pump is disposed in each of the right and left transaxle units so as to be driven by power from a prime mover of the vehicle. A variable displacement hydraulic motor is disposed in each of the right and left transaxle units and is fluidly connected to the corresponding hydraulic pump so as to drive the corresponding right or left axle. A movable motor displacement control member is provided in each of the transaxle unit so as to be moved to change the displacement of the corresponding hydraulic motor. An interlocking connection means is connected to both the movable motor displacement control members of the respective hydraulic motors.

Abstract: A method and apparatus for controlling a hydraulic power system is provided that includes a hydraulic motor and a hydraulic pump configured to supply hydraulic fluid to the hydraulic motor. A relief valve is provided that is configured to release hydraulic fluid from a location between the hydraulic pump and the hydraulic motor when a pressure of the hydraulic fluid exceeds a predetermined relief pressure. Above a predetermined threshold pressure for the system, the displacement of the pump is adjusted to at least a minimum displacement that is based on a total demanded flow for the system that includes a desired flow of hydraulic fluid across the relief valve and a first hydraulic fluid flow consumed by the motor.

Abstract: A hydrostatic drive including a hydrostatic pump configured to supply a transmission fluid. The hydrostatic drive further includes an axle motor and a drum motor. The axle motor is configured to drive a set of traction wheels and the drum motor is configured to drive a drum. The hydrostatic drive also includes an axle drive line and a drum drive line. The axle drive line and the drum drive line are connected to the axle motor and the drum motor respectively to supply the transmission fluid. A manifold integrally connected to the hydrostatic pump to operatively couple the axle drive line and the drum drive line with the hydrostatic pump.

Abstract: The invention relates to a drive system for an infeed conveyor (22) of a harvester (10), having an adjustable hydraulic pump (66), the flow rate and flow direction of which can be adjusted by means of a first actuator (76), said hydraulic pump being connected to a hydraulic motor (68) which drives the infeed conveyor (22). A controller (70) is connected to a foreign-body detection device (108) and to a first valve (90) for controlling the actuator (76) that controls the hydraulic pump (66). The controller (70) controls the first valve (90) at least for a short time by reversing the flow direction is a foreign body appears. In addition, it is suggested that the hydraulic motor (68) has an adjustable displacement volume, and that the controller (70) increases the hydraulic motor displacement volume (68) is a foreign body appears.

Abstract: A control system for use with a machine having an engine is disclosed. The control system may have a cooling circuit, a heat exchanger associated with the cooling circuit, and a sensor configured to generate a signal indicative of a temperature of the cooling circuit. The cooling system may also have a fan mechanically driven by the engine to direct air through the cooling circuit, and a controller in communication with the sensor and the engine. The controller may be configured to adjust a speed of the engine based on the signal.

Abstract: An object is to provide an electric supercharging device that has a high degree of freedom in layout and can suppress the generation of heat from an electric motor. The electric supercharging device 1 includes an electric motor 2, a compressor 3 that supercharges intake air for a vehicle engine, a hydraulic accelerator 10 that accelerates the rotation of the electric motor 2 and transmits the rotation to the compressor 3, and rotation speed adjustment means 4 that controls the rotation speed of the electric motor 2 and an acceleration ratio of the hydraulic accelerator 10 and adjusts the rotation speed of the compressor 3.

Abstract: By accurately determining timing for suppressing overrun in a hydraulic motor or the like, work efficiency is prevented from falling. A. pressure difference ?P between pressure Pa on a discharge port side of a hydraulic pump and pressure Pb on suction port side of the hydraulic pump is calculated on the basis of the detected travel direction of the vehicle and the pressure Pa relative to Pb detected at the respective port sides of the hydraulic pump. At least one of an engine and the hydraulic pump is controlled, according to the calculated pressure difference, such that overrun of at least one of the engine, the hydraulic pump, and a hydraulic motor is suppressed.

Abstract: In a work vehicle, a control section increases the displacement of a hydraulic motor for travel when the drive circuit pressure becomes larger than a target pressure determined according to the engine rotational speed, and reduces the displacement of the hydraulic motor when the drive circuit pressure becomes smaller than the target pressure. The control section increases the target pressure of the hydraulic motor for travel when changing the matching point of the absorption torque curve of the hydraulic pump with respect to the output torque curve of the engine.

Abstract: The present invention provides a hydraulic drive apparatus which can flexibly be set. The hydraulic drive apparatus which drives a variable displacement hydraulic motor 20 by a pressure oil discharged from a variable displacement hydraulic pump 10 and outputs a driving force of the hydraulic motor 20 to outside. The hydraulic drive apparatus includes torque upper limit setting unit which sets an upper limit of an output torque with respect to the hydraulic motor 20, and control unit which sets a maximum capacity limit value of the hydraulic motor 20 in accordance with the upper limit of the output torque when the upper limit of the output torque is set by the torque upper limit setting unit, and which sets a maximum capacity limit value of the hydraulic pump 10 in accordance with the upper limit of the output torque.

Abstract: The invention relates to a hydrostatic drive having one hydraulic pump unit (3) and at least one first hydraulic motor unit (14) and a second hydraulic motor unit (15). The first hydraulic motor unit (14) and the second hydraulic motor unit (15) are connected in parallel with the hydraulic pump unit (3) in a hydraulic circuit. A flow divider (80) is provided between the two hydraulic motor units (14, 15) and the hydraulic pump unit (3). The first working line (7) connecting the flow divider (80) with the hydraulic pump unit (3) is connected to a pressure control valve (23).

Abstract: The present invention relates to a hydraulic drive system having a pressure-regulated hydraulic pump for the provision of a system pressure and having a secondarily regulated hydraulic motor. In accordance with the invention, a control is provided which sets the desired system pressure during operation in dependence on an operating parameter of the hydraulic motor.

Abstract: A hydrostatic assembly includes a pump having a yoke and an associated rotating group. The pump yoke has a bucket portion and an arm portion. At least one fluid passage extends through the pump yoke. The hydrostatic assembly also includes a motor having a yoke and an associated rotating group. The motor yoke also has a bucket portion and an arm portion. At least one fluid passage extends through the motor yoke. The arm portion of the pump yoke and the arm portion of the motor yoke have associated coupling portions for fluidly coupling the pump yoke to the motor yoke so that the at least one fluid passage in the pump yoke is in direct fluid communication with the at least one fluid passage in the motor yoke.

Abstract: A hydrostatic continuously variable transmission includes a swash plate type plunger hydraulic pump and a swash plate type plunger hydraulic motor connected via a hydraulic closed circuit, an inclined angle of a swash plate of the hydraulic motor is variably controlled for continuous shift control. A lock-up mechanism closes the hydraulic closed circuit to make lockup executed when the quantity of oil that flows from the hydraulic pump into the hydraulic motor decreases according to variable control over the inclined angle of the swash plate. The input rotation of the hydraulic pump and the output rotation of the hydraulic motor are substantially synchronous. The lock-up mechanism is operated when lockup control oil pressure is applied and closes the hydraulic closed circuit. A lockup control oil passage that supplies the lockup control oil pressure is provided with an opening opened and closed according to the inclination of the swash plate.

Abstract: The invention relates to a hydrostatic drive (1) and to a method of braking a hydrostatic drive (1). In the hydrostatic drive (1), in a closed circuit a hydraulic pump (3) is connected by a first and a second working line (11, 12) to a hydraulic motor (4). The hydrostatic drive (1) comprises a brake actuation device (37) as well as at least one pressure relief valve (26, 30), which is connected to the working line disposed downstream of the hydraulic motor (4). The hydraulic pump (3) upon detection of an actuation of the brake actuation device (37) is adjustable to a braking delivery rate. The hydraulic motor (4) is adjusted in dependence upon the actuating intensity of the brake actuation device (37) in the direction of a larger absorption volume if the actuating intensity of the brake actuation device (37) increases.

Abstract: A hydrostatic assembly includes a pump having a yoke and an associated rotating group. The pump yoke has a bucket portion and an arm portion. At least one fluid passage extends through the pump yoke. The hydrostatic assembly also includes a motor having a yoke and an associated rotating group. The motor yoke also has a bucket portion and an arm portion. At least one fluid passage extends through the motor yoke. The arm portion of the pump yoke and the arm portion of the motor yoke have associated coupling portions for fluidly coupling the pump yoke to the motor yoke so that the at least one fluid passage in the pump yoke is in direct fluid communication with the at least one fluid passage in the motor yoke.

Abstract: A hydraulic-drive work vehicle includes a plurality of variable capacity hydraulic motors which are rotated by receiving pressure oil from a variable capacity hydraulic pump. Wheels provided at two or more axles are rotated due to torques of the hydraulic motors. The work vehicle is provided with a traveling stabilizer, the traveling stabilizer including a traveling-state detector for detecting a traveling state of the vehicle, and a controller which receives a signal from the detector and varies a capacity of at least particular one of the plurality of hydraulic motors according to the traveling state of the vehicle.

Abstract: A system and method for substantially simultaneously shifting the speed of a plurality of multiple-speed motors that have shifting valves. The system and method includes substantially simultaneously applying an equal shifting force to all shifting valves, resisting shifting of all shifting valves with an equal biasing force arising from deflection of springs contained in springs chambers, and fluidly communicating all spring chambers with a common receptacle to equalize the pressure in all spring chambers.

Abstract: The transmission includes an orbital gear complex in combination with a variable hydraulic pump and motor. The input to the transmission is increased in speed by the orbital gearing such that, when the pump and motor are not operating, the orbiter is stationary, and the orbital gearing produces an overdrive condition. A gear reduction is accomplished by rotating the web with the web-rotating device, providing a high gear reduction. The pump and motor are preferably long-piston hydraulic machines with infinitely variable swash plates. The hydraulic machines preferably have wobblers stabilized by full gimbals and hold-down plates with elongated holes for the long pistons to eliminate possible impacts between the hold-down plates and the head ends of the long pistons when the swash-plates are at or near their maximum angle of inclination.

Abstract: A load control structure for a work vehicle comprises: a device for detecting operating position of a manually operated speed change operating element; an engine load detection device for detecting load on an engine of the work vehicle; a swash plate position detecting device for detecting an operating position of a swash plate of a variable displacement pump of a hydrostatic continuously variable speed change device; a pump operating device for steplessly operating the swash plate of the variable displacement pump; a motor operating device for operating a swash plate of a variable displacement motor of the hydrostatic continuously variable speed change device between at least two speed change positions including a higher speed position and a lower speed position; a control device for controlling the operations of the pump operating device and the motor operating device.

Abstract: A hydrostatic continuously variable transmission includes a swash plate type plunger hydraulic pump and a swash plate type plunger hydraulic motor connected via a hydraulic closed circuit, an inclined angle of a swash plate of the hydraulic motor is variably controlled for continuous shift control. A lock-up mechanism closes the hydraulic closed circuit to make lockup executed when the quantity of oil that flows from the hydraulic pump into the hydraulic motor decreases according to variable control over the inclined angle of the swash plate. The input rotation of the hydraulic pump and the output rotation of the hydraulic motor are substantially synchronous. The lock-up mechanism is operated when lockup control oil pressure is applied and closes the hydraulic closed circuit.

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 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: With a hydrostatic multi-motor drive unit with a least two hydraulic motors acting upon a common load, a solution should be created, with which a further operating range is covered by the use of several motors and at the same time a simple as possible and problem free coupling of the motors is assured. Furthermore, a method for controlling the drive unit is indicated, which permits continuous transitions between the different operating ranges. This is achieved in that the motors (2, 3) are connected with each other through at least one freewheel device (4), in which the motor (2) arranged after the freewheel device has a variable displacement volume.

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 drive system of a working vehicle including a main engine drivingly connected to a hydraulic pump. The hydraulic pump is connected to first and second hydraulic motors. When an undesirable operating condition is detected, a control device shifts an actuator associated with at least one of the wheels, to reduce the displacement volume of the hydraulic motors driving that wheel. In addition, shifts are made in the actuator of the respective other hydraulic motor and/or in the actuator of the hydraulic pump, in order to maintain a constant speed of travel. The control device shifts the actuator of the hydraulic motor of the other wheel toward greater displacement, and if that shift is insufficient to compensate for the undesirable operating condition, the control device will shift the actuator of the hydraulic pump in the direction of reduced displacement volume.

Abstract: A hydrostatic vehicle driving system structured from an engine to a drive axle in a working vehicle. A hydraulic pump driven by the engine and a variable displacement hydraulic motor for driving the drive axle are fluidly connected with each other through a hydraulic circuit. A motor capacity control system controls capacity of the hydraulic motor in correspondence to the condition of load on the engine. The motor capacity control system comprises load-detection means detecting hydraulic pressure in the hydraulic circuit replacing the load on the engine, a hydraulic actuator for changing the capacity of the hydraulic motor, and actuator-control means controlling the hydraulic actuator according to the detection of hydraulic pressure by the load-detection means.

Abstract: The purpose of the invention is to enable a crawler tractor to brake and stop certainly without applying a load to an engine and a driving mechanism, and without complicated operation. An operation link links a conic linkage (53) which links a steering wheel (7) with a main speed change lever (55) of the crawler tractor, and with an operation mechanism of a brake pedal (54). A neutral return mechanism for the operation link is provided. The operation link neutral return mechanism comprises a hook-like cam lever (61). When the brake pedal is depressed, the main speed change lever is moved to its neutral position before braking force occurs, and then, the brake is actuated. Accordingly, engine brake is used effectively, and the brake can be miniaturized.

Abstract: During idling control with an acceleration switch ON, operation of the accelerator pedal is stopped. When stoppage of the operation of the accelerator pedal is detected for a predetermined time period, along with closing a slowdown switch, an idling changeover switch is changed over to its contact a. And the engine rotational speed is gradually slowed down by a command from a slowdown control section. On the other hand, when stoppage of the operation of an operation lever is detected for a predetermined time period, the idling changeover switch is changed over to its contact c. Due to this, the engine rotational speed is instantly controlled to the idling rotational speed.

Abstract: A forward/backward switching control apparatus for a hydraulic drive vehicle that includes the following structures. A variable displacement type hydraulic pump driven by an engine for discharging pressure oil in both directions. An electromagnetic pump inclination angle control mechanism making the discharge displacement of the variable displacement type hydraulic pump variable and for causing the same to discharge in both directions. An electric control outputting signals to run the hydraulic drive vehicle forward, backward and forward/backward. A control device outputting, when the electric control is switched forward/backward to output the forward/backward signal and when the time for switching the forward/backward signal is not longer than a preset time, a first modulate signal for delaying the return times from the forward position to the neutral position and from the backward position to the neutral position to the electromagnetic pump inclination angle control mechanism.

Abstract: A hydrostatic vehicle driving system structured from an engine to a drive axle in a working vehicle. A hydraulic pump driven by the engine and a variable displacement hydraulic motor for driving the drive axle are fluidly connected with each other through a hydraulic circuit. A motor capacity control system controls capacity of the hydraulic motor in correspondence to the condition of load on the engine. The motor capacity control system comprises load-detection means detecting hydraulic pressure in the hydraulic circuit replacing the load on the engine, a hydraulic actuator for changing the capacity of the hydraulic motor, and actuator-control means controlling the hydraulic actuator according to the detection of hydraulic pressure by the load-detection means.

Abstract: A hydrostatic transmission includes a pump and a motor, each of which is an axial piston engine utilizing a swashplate design. The pump and the motor are located coaxially one behind the other and are connected to each other. To expand the range of possible uses of the hydrostatic transmission and retain its compact size, the motor has a hollow output shaft, through which a power take-off shaft driven by a drive shaft of the pump is routed. The swashplate of the pump and the swashplate of the motor can be located on opposite ends of the hydrostatic transmission. Axially between the cylinder drum of the pump and the cylinder drum of the motor there is a common control base mount which is provided with supply channels.

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: A hydrostatic vehicle driving system structured from an engine to a drive axle in a working vehicle. A hydraulic pump driven by the engine and a variable displacement hydraulic motor for driving the drive axle are fluidly connected with each other through a hydraulic circuit. A motor capacity control system controls capacity of the hydraulic motor in correspondence to the condition of load on the engine. The motor capacity control system comprises load-detection means detecting hydraulic pressure in the hydraulic circuit replacing the load on the engine, a hydraulic actuator for changing the capacity of the hydraulic motor, and actuator-control means controlling the hydraulic actuator according to the detection of hydraulic pressure by the load-detection means.

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). All 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: 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: A hydraulic controller comprises a structure composed of a separator plate 70 sandwiched between first and second valve bodies 60a and 80a, in which structure, an oil passage 103 connecting a SC shift valve 92 provided upstream and a SC backup valve 94 provided downstream is provided with a choke 75. When the separator plate 70, in which a choke opening 75a is formed, is sandwiched between the first and second valve bodies, the upstream part of the oil passage 103 is in fluid communication with one end of the choke opening 75a while the downstream part of the oil passage 103 is in fluid communication with the other end of the choke opening 75a. In this arrangement, a long narrow room formed by the choke opening 75a sandwiched between the first and second valve bodies comprises the choke 75.

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: To moderate the efficiency of engine braking when it is applied while a continuously variable transmission produces a large transmission ratio. Such a continuously variable transmission is constituted by a hydraulic pump having an input rotary member connected to an internal combustion engine of a vehicle, a hydraulic motor having an output rotational axis connected to a driving wheel. The hydraulic pump and hydraulic motor are coupled via a first oil passageway, which has a low oil pressure during the normal load operation of the engine but has a high oil pressure during the reverse load operation of the engine, and a second oil passageway, which has a high oil pressure during the normal load operation but has a low pressure during the reverse load operation, thereby forming a closed oil passageway circuit. At least the hydraulic pump or the hydraulic motor has a variable capacity.

Abstract: A hydrostatic vehicle driving system structured from an engine to a drive axle in a working vehicle. A hydraulic pump driven by the engine and a variable displacement hydraulic motor for driving the drive axle are fluidly connected with each other through a hydraulic circuit. A motor capacity control system controls capacity of the hydraulic motor in correspondence to the condition of load on the engine. The motor capacity control system comprises load-detection means detecting hydraulic pressure in the hydraulic circuit replacing the load on the engine, a hydraulic actuator for changing the capacity of the hydraulic motor, and actuator-control means controlling the hydraulic actuator according to the detection of hydraulic pressure by the load-detection means.

Abstract: A brake design for a hydrostatic transaxle having a center section mounted in the transaxle housing and a pump and motor mounted on the center section. A disk brake assembly having at least one rotor is connected to the motor shaft and is entirely mounted in the housing. The design may also include a rotatable actuator mounted in the housing and extending therefrom for engaging the brake assembly.

Abstract: An improved hydrostatic transmission which is compact, reliable and economical to manufacture, including a novel means for reducing the speed of the input to the transaxle using both hydraulics and mechanical gearing; an improved differential which is stronger and less complicated than prior art designs; a more effective and efficient means for braking the transaxle, an improved means for hydraulically bypassing the hydrostatic transmission and a unique check valve arrangement for maintaining oil pressure within the hydrostatic transmission.

Abstract: An object of the present invention is to provide a hydrostatic transmission system integrally constructed without being large-sized while incorporating a variable displacement motor therein.In order to accomplish the object, a casing 11 has a variable displacement pump 1 and a variable displacement motor 3 incorporated therein in a manner to be juxtaposed to each other. The pump 1 is constituted by a cam plate type axial plunger pump which is constructed so as to render a tilting angle of a cam plate 18 variable and render a discharge rate of hydraulic fluid zero when the tilting angle is within a range set near 0 degree. The motor 3 is constituted by a cam plate type axial plunger motor including a cam plate 33 of which a tilting angle is variable.A cover 48 is provided with a pair of passages 2a and 2b, relief valves 9a and 9b, check valves 10a and 10b, and a change-over valve 5.

Abstract: An axle driving apparatus includes a first axle driving unit (18L) having a housing (40) and a single axle (20L). 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 is disposed in the enlarged region. The speed change assembly 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). A second axle driving unit (18R) having similar construction is adjacently disposed to the first axle driving unit (18L). However, the second axle driving unit (18R) features a single axle (20R) being disposed on the opposite side of the single axle (20L) of the first axle driving unit (18L).

Abstract: A relief pressure controlling device comprises a driving side relief pressure controlling valve, a capacity detector which detects the capacity of a hydraulic pump, and an engine throttle opening detector. When the hydraulic pump and the hydraulic motor which are connected by a first oil passage and a second oil passage constituting a hydraulic closed circuit are driven by an engine, the relief pressure controlling valve controls the relief pressure of the oil passage on the driving side that is either the first oil passage or the second oil passage whose pressure becomes higher than the other, to a target relief pressure. The target relief pressure is determined in correspondence with the engine output and corrected on the basis of the pump efficiency which is predetermined in relation to the capacity of the hydraulic pump and to the throttle opening, and this corrected target relief pressure is set as a driving side target relief pressure.

Abstract: A continuously variable transmission includes a housing enclosing an axial piston pump and an axial piston motor arranged concentrically with respect to the pump. The pump and motor have cylinder blocks with axial cylinders, each receiving a piston. Pump and motor swash plates are engaged with the pump and motor pistons for rotating and nutating relative to the cylinder blocks to convert between fluid pressure power and rotating mechanical power. Input and output shafts are journaled in the housing for rotation about a central axis and have inner ends coupled to the pump and to the motor swash plate, respectively. Fluid passages between the pump cylinder block and the motor cylinder block convey fluid pressurized in the pump to the motor cylinders and convey spent fluid displaced from the motor cylinder block back to the pump cylinders.

Abstract: An infinitely variable hydrostatic transmission includes an input shaft connected to drive a hydraulic pump unit, a grounded hydraulic motor unit, and an output shaft. A swashplate assembly is connected to impart output torque to the output shaft resulting from the pumped exchanges of pressured hydraulic fluid between the hydraulic pump and motor units. A ratio controller is linked to independently, variably position input and output members of the swashplate assembly and thus vary nutating magnitudes of cylinder blocks of the hydraulic pump and motor units, pursuant to adjustably setting ratio conditions of the transmission.

Abstract: An axle driving apparatus is provided an includes a main casing, a cap plate coupled to the main casing along a first split line where the first split line is substantially disposed in a horizontal plane, and an axle cap coupled to the main casing along a second split line where the second split line is substantially disposed in a vertical plane. A center section is supported solely by the main casing and has connected thereto a hydraulic pump and a hydraulic motor where the center section is disposed offset from both the first split line and the second split line. A pump shaft is linked to the hydraulic pump and is supported by the main casing where the pump shaft has an axis disposed perpendicular to the horizontal plane and parallel to and offset from the vertical plane. A motor shaft is linked to the hydraulic motor and has an axis parallel to and offset from the horizontal plane and perpendicular to the vertical plane.

Abstract: A continuous hydrostatic-mechanical power division transmission has at least two operating ranges between which it is switched by shift elements, with a first, mechanical part (II) including a planetary differential gear (13) and a second, hydrostatic part (I) including two power-linked adjustable hydraulic units (H1 and H2) which can be operated in both directions either as a pump or as a motor and which are coupled to the mechanical part (II). An annulus (19) of a planetary differential (13) is used to control the direction and speed of rotation of a gear box output shaft (12) in the individual operating ranges and is coupled to the first hydraulic unit (H1). In a first operating range, the second hydraulic unit (H2) drives via a gear-shift element (K1, K2) to the output shaft (12). The first hydraulic unit (H1) coupled to the annulus (19) works as a pump while the second hydraulic unit (H2) works as a motor.