Abstract: A hydrostatic transaxle axle assembly for a vehicle such as a grass mowing lawn or garden tractor comprising a housing for an internally disposed hydrostatic transmission having a variable-displacement hydraulic pump fluidly connected to a fixed-displacement hydraulic motor, the hydraulic motor being connected by differential gearing to axle shafts supported in the housing. The housing is formed by three housing members, two of which are preferably separable on a parting plane coincident with the longitudinal axes of the axle shafts. One of the housing members being provided with an opening to allow a portion of one of the other housing members to extend through, and where the extending housing member contains within its interior a number of internal fluid passages for fluidly connecting the hydraulic pump to the hydraulic motor.

Abstract: A hydrostatic transaxle axle assembly for a vehicle such as a grass mowing lawn or garden tractor comprising a housing for an internally disposed hydrostatic transmission having a variable-displacement hydraulic pump fluidly connected to a fixed-displacement hydraulic motor, the hydraulic motor being connected by differential gearing to axle shafts supported in the housing. The housing is formed by three housing members, two of which are preferably separable on a parting plane coincident with the longitudinal axes of the axle shafts. One of the housing members being provided with an opening to allow a portion of one of the other housing members to extend through, and where the extending housing member contains within its interior a number of internal fluid passages for fluidly connecting the hydraulic pump to the hydraulic motor.

Abstract: A hydrostatic transaxle axle assembly for a vehicle such as a grass mowing lawn or garden tractor comprising a lly disposed hydrostatic transmission having a variable-displacement hydraulic pump fluidly connected to a fixed-displacement hydraulic motor, the hhousing for an internaydraulic motor being connected by differential gearing to axle shafts supported in the housing. The housing is formed by at least three housing members, two of which are separable on a first parting-plane arranged to be perpendicular with respect to the longitudinal axes of the axle shafts. One or two of the housing members being provided with an opening to allow a portion of another housing members, called the radiator member portion to extend through, and where the extending portion contains within its internal structure a number of fluid power transmitting passages arranged for the purpose of fluidly connecting the hydraulic pump with the hydraulic motor.

Abstract: An improved hydrostatic transmission useful as a speed changing device having a single output shaft or a pair of outwardly extending shafts for use, for example, in small vehicles such as lawn and garden tractors. The hydrostatic transmission output may be mechanically coupled to the wheel driving axle by a gear or chain drive, or alternatively may have such means included in the same housing package containing the hydrostatic transmission. When a differential action is needed between the drive wheels of the vehicle, the differential may then also be included in the same housing package. In whichever of such configurations, the hydrostatic transmission comprises a radial piston pump fluidly coupled to a single or twin larger displacement axial piston motor of the swash-plate type by means of a fluid coupling valve supported by the housing.

Abstract: An axle assembly for use in lawn tractors, pedestrian walk-behind mowers and snow blowers in the form of a housing having an internally disposed hydrostatic transmission and speed reducing gearing. An input shaft supported in the housing for driving a variable-displacement hydraulic pump of the hydrostatic transmission, the pump fluidly coupled to a fixed-displacement hydraulic motor of the hydrostatic transmission, and where the motor is drivingly connected through the speed reducing gearing to an output axle shaft or shafts. A mechanical differential disposed within said housing for applications requiring differential speeds of said axle output shafts. The housing being formed by three housing members and joined together along a substantially planar and horizontally peripheral seam formed there between such that two of said housing members are to one side of said seam and join with the third housing element.

Abstract: A hydrostatic transmission having a housing for an internally disposed variable-displacement hydraulic pump and fixed-displacement hydraulic motor, a framework for supporting the hydraulic pump and motor components within said housing in a manner whereby the loads generated by the pressure medium flowing between pump and motor are absorbed into the framework. The framework to support a pintle-valve which as the fluid coupling means between pump and motor.

Abstract: A hydraulic reciprocating piston machine having a housing, a rotatable cylinder-barrel having a series of cylinders and each cylinder containing a piston which is operatively connected to a reaction member. The reaction member being urged by the forces created from those pistons subject to the pressure phase of the working cycle toward and against an abutment-member. The reaction member is purposefully provided with a limited freedom for movement with the housing, and the action of the pistons forces in urging the reaction member towards the abutment-member provides for a substantial reduction in the normal vibration of the reaction member without binding between the adjacent bearing surfaces.

Abstract: A hydrostatic transaxle axle assembly for a vehicle such as a grass mowing lawn or garden tractor comprising a housing for an internally disposed hydrostatic transmission having a variable-displacement hydraulic pump fluidly connected to a fixed-displacement hydraulic motor, the hydraulic motor being connected by differential gearing to axle shafts supported in the housing. The housing is formed by three housing members, two of which are preferably separable on a parting plane coincident with the longitudinal axes of the axle shafts. One of the housing members being provided with an opening to allow a portion of one of the other housing members to extend through, and where the extending housing member contains within its interior a number of internal fluid passages for fluidly connecting the hydraulic pump to the hydraulic motor.

Abstract: A radial piston hydrostatic machine having an outer housing structure and defining an internal chamber, a drive-shaft supported in the housing and operatively connected to the cylinder-barrel, the cylinder-barrel having a number of radial cylinders, each cylinder containing a piston such that the pistons bear on the track-ring, the track-ring eccentrically position within the internal chamber by means of fixed abutment means in the housing, the abutment means disposed radially adjacent the track-ring for resisting the action of the pistons on the track-ring and thereby suppressing vibration emanating from the track-ring.

Abstract: A housing for a hydraulic piston machine comprising two shells of part-cylindrical form, the shells connectable together along a parting plane in which the rotating axis of the drive-shaft lies to contain within internal working elements of the machine. Either or both housing shells may be provided with a opening connecting the interior to the exterior of the shell(s) to provide means for fluid distribution of the machine. A non-deformable liner-element located within one or more of said openings for isolating pressurized fluid passing through the machine from coming into direct contact with the housing shells.

Abstract: A motion transmitting device comprising input and output drive shafts. An eccentric is provided on the input drive shaft and supports a carrier in which an array of pins are disposed. The pins are extended from one end face of the carrier for intermittent engagement with respective "open mouthed" openings provided in a reaction plate fixed to the housing of the device in order to define the gyratory motion of the carrier. The output shaft is provided with a geared member, and where between adjacent teeth on the geared member, a profile of part semi-circular shape is provided which become sequentially and intermittently engaged by all the pins during one complete rotation of the output shaft, and where the number of teeth is one less than the number of pins.

Abstract: A hydrostatic piston machine having a housing comprising two shells of a part-cylindrical form, the shells connectable together along a parting-plane in which the central axes of the drive-shaft and cylinder-barrel lie. Each housing element is provided with a number of semi-circular formations and recesses which form pockets or apertures when the housing shells are connected together to provide support surfaces for the working elements of the machine. A cylinder-barrel mounted within a chamber formed between the shells and is provided with a number of cylinders each containing a piston. Fluid-passageways are provided in the housing to receive and supply fluid to the pistons of the machine.

Abstract: A radial piston hydrostatic machine contained within a housing and comprising a cylinder-barrel mounted to rotate on a pintle-valve fixed to said housing. Two hydraulic-rams operatively acting on a track-ring to provide eccentric displacement relative to the pintle-valve to change the rate of fluid output from the machine. The hydraulic-rams being of unequal size and subjected to the same level of machine discharge pressure during periods when the level of discharge pressure is insufficient to cause an internally disposed pressure relief-valve to "open". A throttle-valve disposed in a fluid channel linking the cylinders of said hydraulic-rams and arranged to introduce a pressure differential across two said two cylinders during periods when the machine discharge pressure is sufficiently high to cause said pressure-relief-valve to "open".

Abstract: A radial piston hydrostatic machine disposed in a housing, a drive shaft supported in the housing and connecting through bevel pinion and gear to transmit rotation of the shaft to a cylinder barrel. The cylinder barrel provided with generally radial cylinder bores supporting pistons and mounted to rotate on a stationary ported pintle valve fixed to said housing. The cylinder barrel having an axially extending projection to support the bevel gear in spaced relationship with the end of said cylinder barrel, the bevel gear rotating with said cylinder barrel and drivingly connected to said bevel pinion. Fluid bearing means provided on the outer cylindrical surface of said pintle valve to provide a pressure field under said axially extending projection in order to counter any deflection of said bevel gear.

Abstract: A transaxle driving apparatus for a self-propelled vehicle such as a grass-mowing lawn tractor, the transaxle comprising a two-piece housing structure forming an internal chamber for encapsulation of a hydrostatic machine and associated reduction gearing. The hydrostatic machine may comprise in one form a single hydrostatic pump driven by an input shaft rotatably supported in the housing, and fluidly coupled to two hydrostatic motors. In a modified form, the hydrostatic machine may comprise two hydrostatic motors fluidly coupled to a pumping source remotely mounted outside the transaxle.

Abstract: A friction drive unit for use within a transaxle driving assembly in self-propelled vehicles such as grass-mowing lawn tractors, the transaxle comprising a two-piece housing structure forming a number of internal chambers for the encapsulation of the friction drive unit, associated reduction gearing and a mechanical differential. The friction drive may comprise as input members, a pair of driver wheels operatable against a larger driven disc wheel acting as the output member, such that only one driver wheel can be engaged to the driven wheel at any one time, and where the direction of vehicle motion depends on which one of the two driver wheels is in contact with the driven wheel. Each of the driver wheels is subjected to continuous rotation from an input drive shaft and are operatively displaced along the shaft by means of respective sliding yoke means. The output from the driven wheel is connected to the transaxle output shafts by means of high ratio gear reduction means.

Abstract: A transaxle housing is provided for a small-sized vehicle such as a grass-mowing lawn tractor and encloses an internally located hydrostatic transmission in association with speed reducing gearing and mechanical differential for reasons of compactness and simplicity of manufacture. The axle housing comprises two members connected together alone a parting plane to define a number of internal chambers, at least one chamber used to enclose the hydrostatic transmission and remaining chambers enclosing speed reducing gearing and differential. One housing element is provided with a vertical input shaft which is operatively connected through bevel gearing to a hydraulic pump, the pump mounted perpendicular and fluidly coupled to a hydraulic motor, the rotary axis of the hydraulic motor being coincident with the parting plane of the housing and parallel to the rotating axes of the half shafts of the transaxle.

Abstract: A transaxle driving apparatus for a small-sized vehicle such as a grass-mowing lawn tractor, formed from a two-piece housing to encapsulate a hydrostatic transmission with associated reduction gearing and mechanical differential member. One housing element is provided with a vertical input shaft which is drivingly engaged to the hydraulic pump of the hydrostatic transmission by means of bevel gearing. A hydraulic motor of the hydrostatic transmission is provided with a motor shaft, a speed reduction shaft, and a differential gear unit attached to the axle shafts, all shafts other than the input shaft being disposed horizontally along the plane containing the longitudinal axis of the transaxle for economy and compactness.

Abstract: The present invention is a neutral shifting mechanism for a hydrostatic transmission. A motor track ring has a groove and cam slot for receiving a control rod of the transmission, with the control rod having a cam portion for engaging the cam slot to lock the track ring in a position concentric with the pintle of the hydraulic motor, i.e. a neutral position. In the normal position, the cam portion positions the track ring eccentrically, allowing a speed control shaft to shift the hydrostatic transmission by pivoting the pump track ring about the control rod.

Abstract: A hydrostatic machine includes a casing (10) containing a rotary member (12) having radial cylinders (24) each with a piston (25) engaging a track ring (27). The member (20) is coupled to an external shaft (13) via reduction gearing (43,44) which also acts as a gear pump. This can be used to supply external power take-off fluid circuits, or an attached oil filter (64) or internal bearings (47,57) or make-up fluid for the machine via valve (42).