Abstract: A kinetic energy recovery system (KERS) is provided. The KERS (1) comprises a first speed-up gear arrangement (12) having an input (10) connectable to a vehicle powertrain. The KERS further comprises a hydraulic variator made up of first and second bent axis motors (20,22) fluidly connected to one another, wherein at least the first motor (20) is a variable displacement motor, and the first motor (20) is connected to an output of the first speed-up gear arrangement (12). A second speed-up gear arrangement (34) has an input connected to the second motor (22). At least one flywheel (52) is connected to an output of the second speed-up gear arrangement (34), where the at least one flywheel is located in a vacuum within at least one flywheel chamber (58).

Abstract: Various exemplary methods, systems, and devices for controlling a motor of a robotic surgical system are provided.

Abstract: Devices, systems, and methods, include an oxygen delivery device that includes an oxygen delivery module, at least one sensor to detect patient breathing, and a controller configured to control the oxygen delivery module to cause the oxygen delivery module to deliver oxygen to the patient based on data from the at least one sensor such that in response to a determination, based on data from the at least one sensor, that no breathing is detected for a first pre-determined period of time, the controller causes the oxygen delivery module to deliver oxygen to the patient in continuous flow mode, and in response to a determination, based on additional data from the at least one sensor, that breathing is detected for a second period of time, the controller causes the oxygen delivery module to deliver oxygen to the patient in a pulse flow mode.

Abstract: An oxygen delivery device includes an oxygen delivery module configured to deliver a pulse including greater than 100 mL of concentrated oxygen, and a controller configured to control the oxygen delivery module to cause the oxygen delivery module to deliver the pulse including greater than the 100 mL of the concentrated oxygen within approximately first 60% of a patient's inspiratory period. A device includes an oxygen delivery module, a piezoelectric valve coupled to an output of the oxygen delivery module to receive the concentrated oxygen, a driver to electrically actuate the piezoelectric valve, and a controller to control the driver to cause controllable actuation of the piezoelectric valve by the driver to cause controllable opening of the valve to enable oxygen flow to be directed for inhalation by a patient via the piezoelectric valve.

Abstract: Disclosed are devices, systems, and methods, including an oxygen delivery device that includes an oxygen delivery module to produce at least concentrated oxygen, and a gas moving device to deliver air to the oxygen delivery module. The gas moving device includes at least one piston rotatable inside a first chamber defined in a housing, the rotational movement of the at least one piston inside the first chamber resulting in varying pressure generated in a first portion of the first chamber, and a vane member rigidly coupled to the at least one piston, the vane member being configured to move inside a vane chamber defined in the housing, the piston and the vane rigidly coupled to the piston define the first portion of the first chamber and a second portion of the first chamber.

Abstract: Disclosed are horsepower management systems and methods for use on power machines with an engine that powers a drive system. An engine speed control device controls the engine speed. A variable displacement drive pump controlled by a displacement control member provides pressurized fluid to a drive motor. A control system communicates with the engine speed control device and the pump displacement control member. The control system includes a user input device and a command lever rotatably coupled to the displacement control member and capable of receiving the user input. The command lever provides a signal to the engine speed control device in response to the user input. The command lever also commands a given displacement via the displacement control member subject to load forces on the hydrostatic pump transmitted to a limiting mechanism coupled to the command lever and the displacement control member.

Abstract: A device for varying the stroke of first and second hydraulic machines. At least one piston is functionally connected to axes of the hydraulic machines. Depending on power demanded by a driver, the piston can be acted upon, via position and high pressure control valve units of a valve system, with pressures that correspond to a pressure present in the hydraulic machines and that act in a first adjustment direction of the hydraulic machines axes. Pressure in the hydraulic machines is controlled by the position control valve unit and is limited by the high pressure control valve unit. The piston can be acted upon by the valve system with pressures that correspond to the pressure present in the hydraulic machines and that act in a second adjustment direction of the axes of the hydraulic machines, and action of the position control valve unit can be reversed.

Abstract: A device for adjusting the swept volume of a first piston machine (1), of transverse axis design, and a second piston machine (2), of transverse axis design. The device including a common component (4), via which the swept volumes can be adjusted, and a valve (12) which, when a maximum pressure level in the working lines (3) is exceeded, can be rerouted in such a way that the common component (4) reroutes the swept volume in a direction toward the lower power input.

Abstract: A device for adjusting the stroke volume of a first piston engine (1), having a bent-axis design, and a second piston engine (2), having a bent-axis design, and a common component (4) by which the stroke volumes can be adjusted. A valve (12) is provided which, when a maximum pressure level in the working lines (3) is exceeded, the valve (12) is reversed such that the common component (4) reverses the stroke volumes toward a lower power consumption arrangement.

Abstract: In a hydrostatic transmission (HST), a lubricating fluid passage is formed in an input shaft and has a pair of radially opposite lubricating fluid spill ports open at an outer peripheral surface of the input shaft. Both of the radially opposite lubricating fluid spill ports face a lubricated object of the HST. The lubricating fluid passage includes an axial fluid passage and a pair of radial fluid passages that are extended radially from the axial fluid passage to the outer peripheral surface of the input shaft so as to be radially opposite each other. Open ends of the respective radial fluid passages at the outer peripheral surface of the input shaft serve as the respective radially opposite lubricating fluid spill ports.

Abstract: This is a project of mechanical machine, which allowed smoothly change rpm ratio between input and output with principle of conservation of energy (no loss of power) while changing the ratio.

Abstract: A hydraulic stepless transmission having increased layout freedom and a compact structure with the functions of conventional hydraulic stepless transmission retained and having increased easiness of production. In the hydraulic stepless transmission, the movable swash plate (input side swash plate) of a variable displacement plunger hydraulic pump or motor is tilted by a hydraulic servo mechanism. The hydraulic servo mechanism has a power piston connected to one end of the input side swash plate for tilting the swash plate, a servo spool (13) placed normal to the direction of sliding of the power piston and substantially parallel to the input side swash plate, and a feedback link for connecting the servo spool and the input side swash plate.

Abstract: The invention relates to a hydrostatic transmission having two bent axis- or swashplate-type axial piston units which are operated alternately as a pump and as a motor, with the two axial piston units being adjustable together with a pivotable dual yoke or by means of a pivotable dual swashplate. In order to minimize the dead volumes of the two axial piston units, the rotational axes of the two axial piston power units are offset with respect to the pivot axis of the dual yoke or of the swashplate by a magnitude such that, at all pivot angles, the power unit pistons, at dead center, are located in the direct vicinity of the bore end of the cylinder block.

Abstract: A speed change system for work vehicle having a continuously variable transmission device selects a first change gear ratio which is set larger than a smallest change gear ratio, when an engine rotational speed is a first set rotational speed which is set equal or close to an idling rotational speed of an engine; retains the change gear ratio of the continuously variable transmission device at the smallest change gear ratio, when the engine rotational speed is equal to or above a second set rotational speed set on a high-speed side relative to the first set rotational speed; and makes the change gear ratio of the continuously variable transmission device larger between the first change gear ratio and the smallest change gear ratio, as the engine rotational speed at that moment becomes lower, when the engine rotational speed is between the first and second set rotational speeds.

Abstract: The invention concerns a variable pump or hydraulic motor with a drive shaft with a first axis of rotation and first plungers connected to the drive shaft and rotatable around the first axis of rotation. A port plate mounted in the housing can rotate around an axis intersecting the first axis, for adjusting the stroke volume. The port plate positioning drive comprises two counter-acting hydraulic actuators acting on the port plate in the direction of the first plungers.

Abstract: A hydraulic actuator for pump control is disclosed. The hydraulic actuator includes two hydraulically isolated chambers for actuation in one direction and two hydraulically isolated chambers for actuation in an opposite direction. Each of the four chambers is connected to a source of high pressure fluid by an electronically controlled pressure reducing valve.

Abstract: A transmission for use with a machine is disclosed. The transmission may have a pump, a motor fluidly connected to receive pressurized fluid from the pump and propel the machine, and an operator input device configured to generate a signal indicative of an operator desired gear ratio of the transmission. The transmission may also have a controller in communication with the pump, the motor, and the operator input device. The controller may be configured to determine an desired gear ratio of the transmission as a function of the signal, and determine an efficiency loss of the transmission at the desired gear ratio. The controller may also be configured to select a known setting of at least one of the pump and motor that provides the desired gear ratio and accounts for the efficiency loss.

Abstract: It is an object, in a hydraulic stepless transmission, to change capacity of a hydraulic pump to thereby make output characteristic different between forward and reverse travel and obtain efficient output characteristics. In the hydraulic stepless transmission formed of the hydraulic pump 10 and a variable displacement-type hydraulic motor 11 and including control means 4, 10 for carrying out capacity control based on a load received by the hydraulic stepless transmission, a pressure control valve 204 is connected to control pressure portions of the control means 4, 10 for carrying out the capacity control according to pressure in a hydraulic circuit 13 on a discharge side of the hydraulic pump 10 to carry out the capacity control of the variable pump and the motor 11.

Abstract: The purpose of the invention is to simplify the linkage mechanism of a shift operating device and to unitize the shift operating device so as to improve the reliability of assemble accuracy. A forward traveling pedal and a rearward traveling pedal are rotatably supported by a installation plate; the installation plate rotatably supports a shift operating rotary sleeve connected through one link to the basal end of the forward traveling pedal (a forward traveling pedal rotary sleeve) and connected through one link to the basal end of the rearward traveling pedal (a rearward traveling pedal rotary sleeve); the forward traveling pedal, the rearward traveling pedal, the shift operating rotary sleeve and the installation plate are constructed as an integral unit; and the shift operating rotary sleeve is rotated forward and rearward interlockingly with the operation of the forward traveling pedal and the rearward traveling pedal so as to slant swash plates of a hydraulic pump and a hydraulic motor of a HST.

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 variator is provided having a first shaft rotatable around a first longitudinal axis associated with the first shaft and a second shaft rotatable around a second longitudinal axis associated with the second shaft. The variator also has a pump driven by the first shaft. The pump includes a first plurality of drum sleeves attached to a first drum plate tilted at a first angle relative to the first longitudinal axis. The drum sleeves are positioned to slidingly receive a first plurality of piston members. Each piston member is configured to form a seal substantially perpendicular to an axis of an associated drum sleeve. The seal substantially prevents fluid from leaking out of a chamber formed by the piston member end the drum sleeve. The variator further includes a motor fluidly coupled to the pump and configured to drive the second shaft.

Abstract: [Problems] A hydraulic stepless transmission having increased layout freedom and a compact structure with the functions of conventional hydraulic stepless transmission retained and having increased easiness of production. [Means for Solving Problems] In the hydraulic stepless transmission (1), the movable swash plate (input side swash plate (6)) of a variable displacement plunger hydraulic pump or motor is tilted by a hydraulic servo mechanism (3). The hydraulic servo mechanism (3) has a power piston (15) connected to one end of the input side swash plate (6) and tilting it, a servo spool (13) placed normal to the direction of sliding of the power piston (15) and substantially in parallel to the input side swash plate (6), and a feedback link (24) for connecting the servo spool (13) and the input side swash plate (6).

Abstract: It is an object, in a hydraulic stepless transmission, to change capacity of a hydraulic pump to thereby make output characteristic different between forward and reverse travel and obtain efficient output characteristics. In the hydraulic stepless transmission formed of the hydraulic pump 10 and a variable displacement-type hydraulic motor 11 and including control means 4, 10 for carrying out capacity control based on a load received by the hydraulic stepless transmission, a pressure control valve 204 is connected to control pressure portions of the control means 4, 10 for carrying out the capacity control according to pressure in a hydraulic circuit 13 on a discharge side of the hydraulic pump 10 to carry out the capacity control of the variable pump and the motor 11.

Abstract: The invention relates to a hydrostatic transmission having two bent axis- or swashplate-type axial piston units which are operated alternately as a pump and as a motor, with the two axial piston units being adjustable together with a pivotable dual yoke or by means of a pivotable dual swashplate. In order to minimize the dead volumes of the two axial piston units, the rotational axes of the two axial piston power units are offset with respect to the pivot axis of the dual yoke or of the swashplate by a magnitude such that, at all pivot angles, the power unit pistons, at dead centre, are located in the direct vicinity of the bore end of the cylinder block.

Abstract: The invention relates to a hydraulic module for hydrostatic mechanical gearboxes having two swashplates or oblique axis drive units which are integrated in the hydraulic module. The swashplate drive units are mounted in a common housing with parallel drive shafts and each have a rotating cylinder block with expellers which can move therein and which are supported in a sliding fashion on a double swashplate whose pivot angle is adjustable by means of a servo system. The double swashplate is designed to carry out positively coupled common adjustment of the volume flow of the two drive units and is equipped with bearing faces for the expellers of the respective drive units, said bearing faces having different angles of inclination relative to the respective drive shaft. The oblique axis drive units each have a cylinder block with expellers which can move therein and which are each pivotably mounted on the coaxial shafts.

Abstract: An electronic transmission control system that can achieve a transmission ratio based on the operator inputs and the current vehicle operating conditions. The transmission constantly connects the engine to the load, and the transmission ratio is only varied by a change in command from the present invention. The transmission's mechanical function is solely to vary the ratio between its input and output. In using the present invention, an operator must select an operating mode, either automatic or manual, using a two-position switch. While in the automatic mode, the present invention determines the vehicle speed by considering the position of the throttle and the operator's use of brakes. In the manual mode, the present invention further considers the operator's selection of a gear condition.

Abstract: An electronic transmission control system that can achieve a transmission ratio based on the operator inputs and the current vehicle operating conditions. The transmission constantly connects the engine to the load, and the transmission ratio is only varied by a change in command from the present invention. The transmission's mechanical function is solely to vary the ratio between its input and output. In using the present invention, an operator must select an operating mode, either automatic or manual, using a two-position switch. While in the automatic mode, the present invention determines the vehicle speed by considering the position of the throttle and the operator's use of brakes. In the manual mode, the present invention further considers the operator's selection of a gear condition.

Abstract: An axle driving unit having a housing with an axle and a hydrostatic transmission disposed therein. The hydrostatic transmission includes a center section separably attached to the housing and disposed within the housing, a hydraulic pump mounted on a pump mounting surface of the center section, and a hydraulic motor mounted on a motor mounting surface of the center section. The rotary axis of the pump is disposed perpendicular to the axle and the rotary axis of the motor is disposed parallel to the axle. An output shaft is disposed on the rotary axis of the hydraulic motor and is disposed below the pump mounting surface. The axle is disposed above the output shaft.

Abstract: An axle driving unit having a housing (21,22) for supporting a first axle (17) for mounting thereon a first driving wheel (3L), and a longer second axle (18) for mounting thereon a second driving wheel (3R). The axle driving unit is eccentrically mounted on a body frame (1) in proximity to the first driving wheel (3L). A speed change transmission (T) is disposed in an enlarged region of the housing that extends substantially perpendicularly with respect to the axles (17,18). The axle driving unit can thus be easily disposed to the side of a chute (6) of a rear-discharge type lawn tractor.

Abstract: The stump grinder has a rotating cutting wheel that is mounted onto an arm for raising and lowering movement and is driven by a hydraulic motor. The arm is capable of being moved about a generally upright axis to control the rate of laterally feed of the cutting wheel. The actuator movement is controlled as a function of the pressure to the hydraulic motor driving the cutting wheel so that as the pressure increases, the rate of feeding movement laterally of the cutting wheel is reduced. The rate of movement is controlled in both directions of swinging of the post about an upright axis, by utilizing variable opening or proportional flow pilot operated valves on the lines to the actuator for controlling the swing. As pressure to the motor increases the variable outlet or proportional pilot operated valve connected to the pressurized end of the swing actuator opens a greater amount diverts a portion of the hydraulic fluid flow to drain to slow movement of the swing actuator.

Abstract: An axle driving unit having a housing for supporting a first axle for mounting thereon a first driving wheel, and a longer second axle for mounting thereon a second driving wheel. The axle driving unit is eccentrically mounted on a body frame in proximity to the first driving wheel. A speed change transmission is disposed in an enlarged region of the housing that extends substantially perpendicularly with respect to the axles. The axle driving unit can thus be easily disposed to the side of a chute of a rear-discharge type lawn tractor.

Abstract: A control system controls a hydrostatic transmission having an engine driven variable displacement pump coupled to a fixed displacement motor. The pump has a swashplate which is controlled by a control signal generated by the control system. The control system includes a speed command signal generator, a motor speed sensor for generating a sensed motor speed signal, an engine speed sensor for generating an engine speed signal, and a control unit which generates the control signal as a function thereof.

Abstract: To control transmission ratio of a continuously variable hydrostatic transmission including an input shaft, an output shaft, a hydraulic pump unit driven by the input shaft, a grounded hydraulic motor unit, and a wedge-shaped swashplate drivingly, pivotally connected to the output shaft and positioned to accommodate pumped hydraulic fluid exchanges between the pump and motor units. A ratio controller is provided having a pair of hydraulically actuated, differentially sized pistons coupled by a linkage mechanism to pivot the swashplate in opposite transmission ratio-changing directions. The smaller piston is incorporated internally of the output shaft, while the larger piston, of an annular shape, coaxially surrounds the output shaft. The linkage mechanism has geometry effective to translate axial forces exerted by the pistons into amplified ratio-changing moments exerted on the swashplate.

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: A continuously variable hydrostatic transmission includes an input shaft connected to drive a hydraulic pump unit, a grounded hydraulic motor unit, and an output shaft. A wedge-shaped swashplate is pivotally mounted to the output shaft in driving connection to receive output torque resulting from the exchange of pressurized hydraulic fluid between the pump and motor units through ports in the swashplate. A hydraulically actuated ratio controller is pivotally linked to the swashplate to selectively adjust the swashplate angle relative to the output shaft axis and thereby change transmission ratio.

Abstract: A discharge flow control system and method of a hydraulic pump driven by an engine for the minimization of the difference between a discharge mount of flow in the pump and total mount of operating oil necessary to operate each actuator in hydraulic equipment. The control system is provided with a detector which detects the number of rotation of the engine, generates equal number of pulses to the number of rotation, a detector which detects the tilt angle of a swash plate of the pump, a detector which detects the operating displacement of the actuator, a detector which detects the load pressure acting on the pump, and a controll unit which controls a target discharge flow mount of the pump which is suitable for performing a predetermined work based on the number of rotation, the tilt angle, the displacement and the load pressure.

Abstract: A continuously variable transmission, which allows recovering braking energy from a vehicle for later use in accelerating the vehicle and/or engine starting, includes a vane type pump and stator in a case, each with flexible cam rings. The pump cam ring and the stator cam ring can both be flexed to change the displacement of the pump and the stator. A first connection establishes fluid communication between a tapering volume sector of the pump swept volume and a tapering volume sector of the stator unit working volume, and a second connection establishes fluid communication between a flaring volume sector of the pump swept volume and a flaring volume sector of the stator unit working volume. A valve is connected to the first and second connections and a hydraulic accumulator.

Abstract: A continuously variable hydrostatic transmission includes axially aligned input and output shafts journaled by a transmission housing and respectively coupled to a prime mover and a load. The input shaft drives a hydraulic pump unit, while a hydraulic motor unit is grounded to the transmission housing. A wedge-shaped swashplate is pivotally connected to the output shaft in operative position to accommodate pressurized hydraulic fluid exchanges between the pump and motor units. A controller is coupled to adjust the angular orientation of the swashplate relative to the output shaft axis and thus set the transmission ratio. A hydraulic circuit, connected into the hydraulic motor unit, is selectively operable to vent high and low fluid pressure sides of the swashplate to atmosphere, thus imposing a neutral transmission ratio condition regardless of the transmission ratio set by the controller.

Abstract: A method of pumping at a variable delivery flow rate and pressure includes rotating a pump rotor having a plurality of radially extending vanes inside a flexible cam ring with an input shaft and sweeping a swept volume within the flexible cam ring with the vanes while contacting an inside surface of the flexible cam ring with outside edges of the vanes. The swept volume is sealed on opposite axial sides thereof with a port plate on one side and a side seal plate on the side opposite the port plate, and opposite sides of the flexible cam ring and the vanes are engaged with the plates. Fluid is drawn into the swept volume within the cam ring through a first set of ports in the port plate by rotating the vanes into a suction region within the cam ring having an increasing radius in the direction of the vane rotation.

Abstract: A continuously variable transmission includes a pump driven by an input shaft against a wedge-shaped swashplate. Hydraulic fluid pressurized in the pump flows through ports in a pump cylinder block into kidney-shaped slots in the swashplate, and from there flows into and pressurizes a series of cylinders in a motor cylinder block. The pump and motor exert first and second components of torque on the swashplate in the rotational direction on the input shaft, and the hydraulic system pressure in the swashplate slots exerts a third component of torque in the same direction on the swashplate. The third torque component is a product of the hydraulic system pressure and the differential area of the two ends of the high pressure slot at the narrow and thick sides of the wedge-shaped swashplate. The swashplate drives an output shaft through a pin connection intersecting the centerline of the output shaft where it passes through a central opening in the swashplate.

Abstract: A control and regulation device for a vehicle travel drive, which comprises two hydrostatic transmissions (3, 4) of adjustable transmission ratios, each comprising a hydraulic pump (12, 13) and a hydraulic motor (14, 15), which are in driving connection with two vehicle track arrangements (18, 19) and have each an adjustment device (30, 24; 31, 25) controllable with control signals (v.sub.l, v.sub.r) for adjusting the transmission ratio, with a control section comprising a desired-value setting apparatus (5) and a signal processing means (42, 43), whereby the desired-value setting means sets transmission ratio desired-values of each hydrostatic transmission, employing respective adjustable control levers (36, 37), and outputs desired-value signals (s.sub.l, s.sub.r), and the signal processing apparatus processes desired-value signals to control signals (s.sub.l, s.sub.r) and outputs the latter.

Abstract: A controller for changing the ratio of a continuously variable hydrostatic transmission, as determined by the angular position of a swashplate, including an actuator having a cylinder slidingly receiving a piston to define a pair of chambers. A pair of solenoid valves, each configured to connect a respective chamber selectively to sump pump pressure or atmospheric pressure, are energized with a stream of pulses to create differential fluid pressures in the chambers, thereby producing movement of the piston; the piston movement being linked to the swashplate to produce a corresponding adjustment of the swashplate angular position. The rate of change of the swashplate angular position is controlled by pulse width modulating the pulse stream.

Abstract: A continuously variable hydrostatic transmission includes an input shaft connected to drive a hydraulic pump unit, a grounded hydraulic motor unit, and an output shaft. A wedge-shaped swashplate is pivotally mounted to the output shaft in driving connection to receive output torque resulting from the exchange of pressurized hydraulic fluid between the pump and motor units through slots in the swashplate. A hydraulically actuated ratio controller shifts the axial positions of spherical bearings mounting a pump portplate in the hydraulic pump unit and a motor portplate in the hydraulic motor unit to adjust the swashplate angle relative to the output shaft axis and thereby change transmission ratio.

Abstract: A hydrostatic transmission includes wedge-shaped swashplate operatively positioned between a hydraulic pump unit driven by an input shaft and a grounded hydraulic motor unit to accommodate pumped exchanges of hydraulic fluid between the units. The swashplate, drivingly coupled to an output shaft, is angularly adjustable about a pivot axis oriented in intersecting, orthogonal relation to the output shaft axis to infinitely variable transmission ratios. Pilot bearings, mounted by the swashplate, support cylinder blocks of the hydraulic pump and motor units for nutating motions centered on the swashplate pivot axis to minimize the resultant moment on the swashplate. Piston rods in the hydraulic pump and motor units are oriented in outwardly flared, acute angles to the output shaft axis to expand the range of permissible angular adjustment of the swashplate by a ratio controller.

Abstract: The maximum value of target motor speed ratio is calculated from the allowable revolution speed of a motor, and based on the maximum value, an allowable value of target speed ratio is set. Target speed ratio is then limited to the allowable value or less. This enables it to prevent overrun occurring e.g., when the vehicle rolls down a hill.

Abstract: A continuously variable hydrostatic transmission includes an input shaft connected to drive a hydraulic pump unit, a grounded hydraulic motor unit, and an output shaft. A wedge-shaped swashplate is pivotally mounted to the output shaft in driving connection to receive output torque resulting from the exchange of pressurized hydraulic fluid between the pump and motor units through specially configured ports in the swashplate. A hydraulically actuated ratio controller is pivotally linked to the swashplate to selectively adjust the swashplate angle relative to the output shaft axis and thereby change transmission ratio.

Abstract: A continuously variable hydrostatic transmission includes an input shaft connected to drive a hydraulic pump unit, a grounded hydraulic motor unit, and an output shaft. A wedge-shaped swashplate is pivotally mounted to the output shaft in driving connection to receive output torque resulting from the exchange of pressurized hydraulic fluid between the pump and motor units through specially configured ports in the swashplate. A hydraulically actuated ratio controller shifts the axial positions of spherical bearings mounting a pump cylinder block in the hydraulic pump unit and a motor cylinder block in the hydraulic motor unit to adjust the swashplate angle relative to the output shaft axis and thereby change transmission ratio.

Abstract: Hydrostatic transmissions are useful for propelling a machine to do work and travel relative to the ground. In performing work functions and during travel it is desirable to adjust machine speed to aid in handling the machine. The subject hydrostatic transmission control system includes a infinitely adjustable creeper hand lever which can be moved to any desired position and be maintained in the selected position until moved by the operator. A spring biased inching pedal can be used in combination with the creeper lever to further adjust the machine speed. This arrangement of components provides a control system for the hydrostatic transmission which can be adjusted and maintained at a desired setting.

Abstract: A continuously variable transmission includes a pump (258) driven by an input shaft (256) against a wedge-shaped swashplate (260). Hydraulic fluid pressurized in the pump flows through ports (402) in a pump cylinder block (422) into kidney-shaped slots (406) in the swashplate (260), and from there flows into and pressurizes a series of cylinders (394) in a motor cylinder block (366). The pump and motor exert first and second components of torque on a swashplate (260) in the rotational direction on the input shaft (256), and the hydraulic system pressure in the swashplate slots exerts a third component of torque in the same direction on the swashplate (260). The third torque component is a product of the hydraulic system pressure and the differential area of the two ends of the high pressure slot (406P) at the narrow and thick sides of the wedge-shaped swashplate (260).

Abstract: A working machine such as a hydraulic excavator is provided with a working apparatus including a boom pivotally mounted on the body of the working apparatus and a boom-cylinder hydraulic system for the working apparatus. The hydraulic system includes an actuator for moving the boom up and down and a directional selecting valve. The directional selecting valve is arranged to effect selective switching of the feed of a pressurized working fluid to and the discharge of the working fluid from with respect to the rod-side and the bottom-side hydraulic chamber. The hydraulic system further includes a device for relieving the pressure of the bottom-side hydraulic chamber of the actuator. This relieving device is connected to the bottom-side hydraulic chamber of the actuator via a hydraulic circuit. When the pressure in the bottom-side hydraulic chamber changes from rise to fall, the pressure is released to a low-pressure side of the hydraulic circuit, thereby suppressing oscillation of the boom.