Abstract: A hydrostatic drive system is disclosed which allows for simpler and more robust control of hydraulic vibration. The system comprises first and second hydraulic drive units and a variable damping device. At least the first hydraulic drive unit is a variable displacement type and comprises a displacement control. The variable damping device comprises at least one variable element. The system comprises a first linkage apparatus between the displacement control and the variable element and is operable to control the variable element in accordance with the displacement of the displacement control.

Abstract: A hydrostatic drive system is disclosed which allows for simpler and more robust control of hydraulic vibration. The system comprises first and second hydraulic drive units and a variable damping device. At least the first hydraulic drive unit is a variable displacement type and comprises a displacement control. The variable damping device comprises at least one variable element. The system comprises a first linkage apparatus between the displacement control and the variable element and is operable to control the variable element in accordance with the displacement of the displacement control.

Abstract: A multi-disc brake assembly comprising a disc pack may desirably be liquid cooled (i.e. is “wet”) to dissipate the substantial heat generated from braking. In conventional assemblies, coolant fluid is generally delivered in a uniform manner to the discs in the disc pack. However, the heat distribution in the disc pack from braking is not uniform. But wear can be significantly increased where an inadequate amount of coolant is delivered, while drag can be increased unnecessarily where an excessive amount of coolant is delivered. In such an assembly, an improved coolant distribution can be obtained by appropriately varying the size of the numerous orifices which may be used to distribute coolant to the disc interfaces from an axial fluid rail provided in a rotating central shaft. Specifically, the orifices decrease in size from the middle to the ends of the disc pack.

Abstract: A load cancelling hydrostatic system is disclosed comprising at least two hydrostatic modules coupled in parallel. Each hydrostatic module comprises input and output hydraulic piston drive units, each of which is coupled to its respective unit in the other module by common drive shafts. The pistons in a hydraulic piston drive unit of one module are coupled together with those in the respective unit of the other module with a timing angle of about 0°. The design advantageously cancels any axial imbalances and allows for use of radial drive shaft bearings which support an essentially purely radial load. In turn, greater power density and system efficiency can be obtained.

Abstract: A multi-disc brake assembly comprising a disc pack may desirably be liquid cooled (i.e. is “wet”) to dissipate the substantial heat generated from braking. In conventional assemblies, coolant fluid is generally delivered in a uniform manner to the discs in the disc pack. However, the heat distribution in the disc pack from braking is not uniform. But wear can be significantly increased where an inadequate amount of coolant is delivered, while drag can be increased unnecessarily where an excessive amount of coolant is delivered. In such an assembly, an improved coolant distribution can be obtained by appropriately varying the size of the numerous orifices which may be used to distribute coolant to the disc interfaces from an axial fluid rail provided in a rotating central shaft. Specifically, the orifices decrease in size from the middle to the ends of the disc pack.

Abstract: A hydrostatic assembly employing a 1st hydraulic piston drive unit is described in which the output is increased without using additional servo assemblies by incorporating a 2nd hydraulic piston drive unit, coupling the drive shafts of both drive units together, and employing a common means to simultaneously adjust displacement of both the 1st and 2nd hydraulic piston drive units. In such embodiments, coupling the drive shafts together such that the 1st hydraulic piston drive unit is rotationally offset with respect to the 2nd hydraulic piston drive allows for a reduction in the amplitude of pressure pulsations associated with the hydrostatic assembly output, thereby smoothing out operation and improving durability.

Abstract: A hydrostatic variator having a common yoke design and two or more bent axis piston drive units is disclosed in which the rotating group of a drive unit is arranged to be movable relative to the yoke to alter the angle between its drive shaft axis and rotating group axis independent of the other drive unit. This can be accomplished using movable sector plates coupled to the rotating groups that are arcuately movable within the yoke about the axis perpendicular to the respective drive shaft axes of the drive units. Such variators enjoy the response and packaging advantages of a common yoke design while still allowing dynamic adjustment of system size. In turn, varying system size allows for efficiency to be improved at conditions other than at the maximum design torque.

Abstract: An improved split power path transmission with a combiner is disclosed which comprises an input power splitter that splits input power between at least one fixed-ratio mechanical power path and at least one variable-ratio power path. The outputs of the fixed-ratio and variable-ratio power paths are combined by coupling their outputs to a combiner. The transmission also comprises a multi-speed drive assembly comprising at least two selectable gear ratios. The transmission can be made more compact by incorporating the multi-speed drive assembly between the input and output of the variable-ratio power path.

Abstract: A hydrostatic assembly employing a 1st hydraulic piston drive unit is described in which the output is increased without using additional servo assemblies by incorporating a 2nd hydraulic piston drive unit, coupling the drive shafts of both drive units together, and employing a common means to simultaneously adjust displacement of both the 1st and 2nd hydraulic piston drive units. In such embodiments, coupling the drive shafts together such that the 1st hydraulic piston drive unit is rotationally offset with respect to the 2nd hydraulic piston drive allows for a reduction in the amplitude of pressure pulsations associated with the hydrostatic assembly output, thereby smoothing out operation and improving durability.

Abstract: A hydrostatic variator having a common yoke design and two or more bent axis piston drive units is disclosed in which the rotating group of a drive unit is arranged to be movable relative to the yoke to alter the angle between its drive shaft axis and rotating group axis independent of the other drive unit. This can be accomplished using movable sector plates coupled to the rotating groups that are arcuately movable within the yoke about the axis perpendicular to the respective drive shaft axes of the drive units. Such variators enjoy the response and packaging advantages of a common yoke design while still allowing dynamic adjustment of system size. In turn, varying system size allows for efficiency to be improved at conditions other than at the maximum design torque.

Abstract: A hydraulic machine includes a support structure and a rotating group rotatably mounted relative to the support structure. The rotating group includes a shaft and a cylinder barrel with a plurality of circumferentially spaced cylinder bores. Reciprocal pistons extend from the shaft with each one of the pistons extending into an associated one of the cylinder bores. A joining assembly joins the shaft and the cylinder barrel so that the shaft and the cylinder barrel rotate together. The hydraulic machine further includes at least one oil dam associated with the rotating group and adapted to trap hydraulic fluid used for lubricating portions of the joining assembly.

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 machine includes a support structure and a rotating group rotatably mounted relative to the support structure. The rotating group includes a shaft and a cylinder barrel with a plurality of circumferentially spaced cylinder bores. Reciprocal pistons extend from the shaft with each one of the pistons extending into an associated one of the cylinder bores. A joining assembly joins the shaft and the cylinder barrel so that the shaft and the cylinder barrel rotate together. The hydraulic machine further includes at least one oil dam associated with the rotating group and adapted to trap hydraulic fluid used for lubricating portions of the joining assembly.

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: The invention comprises a hydro-mechanical continuously variable transmission (HMCVT) that uses a planetary gear system to provide a combination of hydraulic and mechanical power for a vehicle or stationary equipment. The invention further comprises various ancillary elements to improve the performance of the HMCVT.

Abstract: The present invention relates to a swing boom assembly (10), which has a fixed base (52), a pivot base (40) rotatably mounted on the fixed base, and a boom (60) pivotally coupled to the pivot base. The boom is coupled proximate a lower end of the pivot base and has a hydraulic piston cylinder (59) coupled between the boom and an upper end of the pivot base. The hydraulic piston cylinder is operative to raise and lower the boom. The pivot base has an upper shaft (48), a main body (54) having a pair of spaced apart clevis plates affixed to each end of the upper shaft, and a spherical bearing (50) rigidly mounted around the upper shaft between the clevis plates and said bearing having an outer race rigidly mounted to the fixed base. The hydraulic piston cylinder is coupled to the main body of the pivot base rather than directly to an upper shaft.

Abstract: The invention comprises an electro-mechanical continuously variable transmission (EMCVT) that uses a planetary gear system to provide a combination of electric and mechanical power for a vehicle or for stationary equipment. The EMCVT includes a clutch and brake system that allows power from a energy storage unit to be combined with the main power input (typically an engine) to provide a torque output greater than that available from the main power input alone.

Abstract: A remotely actuated quick-release coupling having a male assembly and a female assembly. The female assembly has an inner sleeve and an outer sleeve, with the male assembly being removably insertable into the inner sleeve. A spring-loaded latching mechanism is located in the female coupling and is automatically engaged when the male assembly is inserted into the female assembly, connecting the coupling. The cylinder defined by the inner and outer sleeve can be pressurized through an external port using either air pressure or hydraulics. When the cylinder is pressurized, the latching mechanism is disengaged, allowing the male assembly to be removed from the female assembly, disconnecting the coupling.

Abstract: The invention comprises a hydro-mechanical continuously variable transmission (HMCVT) that uses a planetary gear system to provide a combination of hydraulic and mechanical power for a vehicle or stationary equipment. The invention further comprises various ancillary elements to improve the performance of the HMCVT.

Abstract: The invention comprises an electro-mechanical continuously variable transmission (EMCVT) that uses a planetary gear system to provide a combination of electric and mechanical power for a vehicle or for stationary equipment. The EMCVT includes a clutch and brake system that allows power from a energy storage unit to be combined with the main power input (typically an engine) to provide a torque output greater than that available from the main power input alone.