Abstract: A drive system includes a vehicle propulsion drive having a speed change gear box which drives tracks through a pair of planetary gears and a steering drive having a pair of variable hydrostatic drives. The hydrostatic drives engage a neutral shaft which superimposes rotation on the planetary gears to provide steering control for the tracks. The neutral shaft is separable into two segments. A differental reversing gear may be employed to selectively couple the neutral shaft segments. When the vehicle travels at high speed, the neutral shaft segments are coupled for unitary rotation. At low vehicle speeds, the propulsion drive is blocked and the neutral shaft segments are uncoupled so that both propulsion and steering are provided through the hydrostatic drives.

Abstract: A drive system includes a vehicle propulsion device having a speed change gear box which drives tracks through a pair of planetary gears and a steering drive having a pair of variable hydrostatic drives. The hydrostatic drives engage a neutral shaft which superimposes rotation on the planetary gears to provide steering control for the tracks. The neutral shaft is separable into two segments. A differential reversing gear may be employed to selectively couple the neutral shaft segments. When the vehicle travels at high speed, the neutral shaft segments are coupled for unitary rotation. At low vehicle speeds, the propulsion drive is blocked and the neutral shaft segments are uncoupled so that both propulsion and steering are provided through the hydrostatic drives.

Abstract: A mechanical gear transmission between an engine and a load includes shiftable speed change gearing. Brakes or clutches are provided for shift synchronization when changing to different speeds. Positioned between the engine and the gearing is a main synchronization element such as a clutch. The primary segment of the main synchronization element is driven by the engine output shaft while the secondary segment drives the input shaft of the speed change gearing. During a gear shift under load, the main synchronization element is maintained in a slip mode for a longer duration than the gearing synchronization element and provides the major portion of the total synchronization work. In alternate embodiments, the main synchronization element is combined with a planetary gearing for speed reduction on a pair of planetary gearings for reversing direction. A further embodiment incorporates a microprocessor controller and sensors for monitoring various engine and transmission functions.

Abstract: A drive system for a tracked vehicle includes a composite transmission having a primary transmission unit and a secondary transmission unit which is driven by components of the primary transmission unit. The primary transmission unit includes a propulsion gear and a steering gear both of which are driven from an engine drive shaft. The secondary transmission unit includes a pair of planetary gear sets which drive a pair of output wheels, tracks or chains of the vehicle. In order to conserve space, the transmission is configured such that the propulsion gear and the steering gear are positioned alongside the engine adjacent the drive shaft end of the engine and the secondary transmission components extend in front of the drive shaft end of the engine with a portion of each planetary gear set projecting alongside the engine.

Abstract: A shiftable planetary gear train is driven by the output of a conventional vehicle transmission which engages a ring gear of the planetary gear train. The planetary gear train includes two shifting sleeves which are axially displaced as a unit. One of the sleeves is rotatably driven by the ring gear while the other sleeve is nonrotatable. In one shift position, the rotatable sleeve is brought into driving engagement with a planet carrier which drives an output shaft thereby fixing the output shaft relative to the ring gear. When the shifting sleeves are unitarily moved to a neutral position, the rotatable sleeve is disengaged from the planet carrier. Further displacement of the shifting sleeves results in locking the sun gear against rotation. This is accomplished by engagement between the nonrotatable sleeve and a spur gear which is fixed to an extension of the sun gear.

Abstract: A drive assembly for tracked vehicles includes a gas turbine engine with separate turbine shafts driving a vehicle propulsion speed change gear box and a steering unit. In one embodiment, the gear box is driven by a working turbine wheel output shaft while an infinitely variable steering unit is driven by a turbine compressor shaft. In an alternate embodiment, the steering unit comprises a reversing gear driving a zero shaft and with the steering unit being driven by a separate stage turbine wheel having adjustable nozzles or vanes. A further embodiment permits the elimination of the reversing gear in the steering unit by providing adjustable turbine vanes and/or blades which are capable of reversing the direction of rotation of the wheel which drives the steering unit shaft. In some embodiments, auxiliary steering power is provided in the event of an engine failure through a power takeoff from the working turbine shaft.

Abstract: A control system for an automatic vehicle transmission includes a clutch mechanism interconnecting the driving connection between the vehicle engine and the vehicle driving wheels. The control system operates to automatically disengage the clutch when the braking system is actuated and the vehicle speed is reduced to a predetermined level with the accelerator in idle position. The clutch automatically engages when any of the three parameters have changed from predetermined levels. The automatic control system serves to reduce fuel consumption and exhaust emissions at vehicle idling by reducing transmission drag, yet provides smooth shifting and permits the engine and transmission to assist in vehicle braking.

Abstract: The disclosure contains a hydrodynamic torque transmitting unit particularly for a hydrodynamic brake. A working chamber that is filled with working fluid contains a stator and a rotor. An inlet valve controls inlet of fluid to the working chamber. A piston connected with the inlet valve selectively closes the valve. The piston initially opens the inlet valve fully for a surge of working fluid into the working chamber. In a stage I condition, valving and pressure chambers associated with the piston returns the inlet valve to an intermediate position reducing the inflow of working fluid into the working chamber after the initial surge. In a stage II condition, the pressure chambers remain continuously pressurized for holding the inlet valve in the condition of maximum supply of working fluid to the working chamber. Various piston arrays are described in different embodiments.

Abstract: A tracked vehicle transmission provides reduced length between an engine output shaft and a transversely oriented main shaft which drives the vehicle tracks. The transmission includes a torque converter having an output shaft which extends across the main shaft. The primary side of the torque converter drives a steering unit and a power take-off shaft which includes a flow brake. The torque converter output shaft drives the main shaft through a gear train on the side of the main shaft opposite the converter. The gear train includes bevel gears which engage a pair of reversing clutches which drive planetary speed change gear sets. A pair of speed change gear sets may be positioned adjacent each of the reversing clutches or a single speed change gear set may be provided depending upon space requirements and installation conditions.

Abstract: A motor-vehicle drive engine has a cooling system to which it is connected via a transmission so that it can drive its own cooling system. A controller responsive to various parameters of the engine, particularly load power requirements, operates the cooling-system transmission through a cutout circuit so as to disconnect the cooling system from the engine when the engine temperature is below a predetermined level so that the full engine output power can be applied to a load. Thus the engine loading, engine output speed, engine heat, accelerator-pedal setting, and/or similar parameters are detected and fed to the controller which automatically cuts the cooling system off for a predetermined fixed interval (controlled by a timer) whenever it is possible for the engine to operate for this interval without the cooling system and the work produced by the engine is otherwise needed. A temperature sensor may reconnect the engine and the fan when the engine temperature rises impermissibly.

Abstract: A tracked vehicle includes an engine driven transmission having a pair of output shafts, each of which engages a planetary gear set for driving chain treads. An infinitely variable, hydrostatic/hydrodynamic, superimposed steering mechanism includes a neutral shaft in engagement with the sun gears of each of the planetary gear sets. The steering mechanism includes a hydrostatic drive unit with a regulating pump having a control lever operatively connected to the vehicle steering wheel and an oil motor having an absorption regulating lever. The steering mechanism also includes a hydrodynamic drive unit which is controlled as a function of the hydrostatic system pressure. Output gears of both steering drive units engage the neutral shaft. A torque control valve includes a plunger which positions the oil motor absorption lever as a function of the hydrodynamic drive speed to increase torque at low drive speeds and reduce torque at high drive speeds.