Zahnraderfabrik Renk Ag

Renk Aktiengesellschaft

Voith Getriebe Kg

Firma Zahnraderfabrik Renk Aktiengesellschaft

Franz X Zaunberger

Artur Kugler

Rudi Reppert

Hans Lindenthal

Klaus Brosius

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. For combined steering control and regulation of slow travel speeds as a function of the requirements of specific operating equipment carried by the vehicle, a control apparatus operates as a function of electrical signals for regulating travel speed and provides, through a linkage, adjustment of the hydrostatic unit controls and, in addition, superimposes upon the adjustment, modification required for steering the vehicle.

Tracked vehicle drive system

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. For combined steering control and regulation of slow travel speeds as a function of the requirements of specific operating equipment carried by the vehicle, a control apparatus operates as a function of electrical signals for regulating travel speed and provides, through a linkage, adjustment of the hydrostatic unit controls and, in addition, superimposes upon the adjustment, modifications required for steering the vehicle.

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. The microprocessor controller actuates the main and the gearing synchronization elements and may control the engine during a gear change.

High efficiency gear transmission

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. In an alternate embodiment, the propulsion gear and steering gear are positioned alongside the engine adjacent the drive shaft end while the secondary transmission components are positioned adjacent the opposite end of the engine.

Compact drive assembly

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. Movement of the shifting sleeves is controlled through a fluid cylinder which is coupled to a shift fork, one arm of which engages a groove in one of the sleeves and the other arm of which engages a groove in the other sleeve. Detents are provided to seat the sleeves in the various shifting positions.

Shiftable planetary gear train

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.

Tracked vehicle drive assembly

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.

Vehicle transmission control system

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. In the various embodiments, different piston arrangements, utilizing two pressure chambers operating selectively together or in opposition to each other, determine the various positions of the piston which moves the inlet valve. Appropriate valving and switches direct the pressure supply to the different pressure chambers at different times for moving the piston as needed to move the inlet valve. The switching is done either through a time delay arrangement and/or through a sensor directly connected with the working chamber for sensing the pressure therein.

Hydrodynamic torque transmitting unit, particularly for a hydrodynamic

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. The steering unit is mounted to the upper transmission casing as a single subassembly and is positioned above the main shaft in an area partially enclosed by the torque converter and the reversing clutches.

Compact transmission for tracked vehicles

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.

Apparatus for controlling the cooling system of a motor-vehicle drive

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. The speed dependent position of the control valve plunger is overridden in the presence of high pressures in the hydrostatic drive unit to increase torque when necessary at high speeds.

Control for tracked vehicle steering mechanism

A full-track vehicle has an engine connected via a pair of differentials to a pair of tracks. A steering shaft extending between the differentials is rotatable in one sense for deflection of the vehicle to one side during forward advance and in the other direction for deflection toward the other side. This steering shaft is connected to the planet carrier of a primary planet gear assembly and to the ring gear of an intermediate planetary gear assembly. The sun gears of both of these assemblies are connected to the output side of a reversible variable-speed transmission whose input side is connected directly to the engine. The ring gear of the primary planetary gear assembly is connectable to a brake which may arrest its rotation and the planet carrier of the intermediate planetary gear assembly is connected to the planet carrier of a left-turn planetary gear assembly and the ring gear of a right-turn planetary gear assembly. The ring gear of the left-turn assembly is provided with a brake as is the planet carrier of the right-turn assembly, and the sun gears of both of these assemblies are directly connected to the engine. For minor deflections the primary brake is closed and the transmission alone directly rotates the sun gear of the primary gear assembly and thereby rotates the steering shaft in the necessary direction. For greater deflection the left- or right-turn brakes are closed and the output rotation of the variable-speed reversible transmission is subtracted from the rotation speed of the sun gears of the turn gear assemblies, and for greatest possible deflection the output rotation of the transmission is added to the rotation of the sun gears. A Z-shaped cam is provided to effect this increasing, decreasing, and reversing operation of the transmission.

Growing community of inventors

Augsburg, Germany

Franz X Zaunberger