Sundstrand Corporation

Frederic W Pollman

David W Reynolds

Jimmy W Bolinger

Richard K Heiser

Stanley W Crull

David N Polaski

William A Ross

The present invention provides an improved control system for a driven cable reel mounted on a vehicle wherein the reel is adapted to pay-in and pay-out electrical cable to supply power to the vehicle, such as a mine car. The control system modifies the torque supplied by the reel drive so as to maintain a relatively constant tension on the cable. The improved control system has a first or basic output which provides higher torque when the reel is paying in cable and provides lower torque when the reel is paying out cable, the difference in drive torque being necessary to compensate for the reversal of frictional characteristics during paying in and paying out of the cable. The control system further provides a transient condition output signal to modulate the drive of the cable reel in a manner which compensates for acceleration and deceleration of the cable reel to reduce cable slack and prevent a sudden increase in cable tension which could cause cable breakage.

Constant tension cable reel drive

A control for a variable displacement motor and operable in either direction of rotation of the motor (10) and which acts on a servo cylinder (55) to set the position of a wash plate (50). The control includes a signal-setting valve (65) operable in response to the rate of fluid flow through the motor by sensing a pressure drop in a closed circuit line to the motor to set a variable control signal and the variable control signal is applied to the displacement-setting mechanism (56,55) for the motor to have a decrease in motor displacement related to an increase in the rate of fluid flow through the motor.

Hydraulic motor control

A pressure override control which utilizes pump output flow for destroking of a variable displacement pump to minimize loss of power and generation of heat and which includes modifications to the displacement control valve for the pump and, particularly, the cross connection of displacement-controlling servo motors when the displacement control valve is in a neutral position with blocking of communication of said servo motors to a displacement control pressure and drain whereby the pump cannot be positioned in a maximum displacement position in response to certain system malfunctions in the power override control circuitry.

Pressure override control

A torque control for a drive system having a hydraulic transmission connectable to a prime mover (30) and having a pair of hydraulically-connected displacement devices V and F, with one device having variable displacement, a torque sensor (35) generates a torque signal representative of prime mover output torque in either driving or braking mode, torque demand generators (47,47') generate a torque demand signal selectively in either driving or braking modes, a governor valve (63) compares the torque signals and generates a control signal and a control servo 17, responsive to the control signal, controls the displacement of the variable displacement device V to eliminate any difference in torque signals.

Input torque control for a variable displacement hydraulic transmission

The present invention is directed to a simplified viscosity compensating circuit which utilizes a viscosity sensitive capillary and a flow restriction means in series therewith to regulate the pressure at a particular point in a control circuit in response to a change in viscosity of the control fluid. Such viscosity compensation in the circuit is utilized to either maintain a uniform pressure at the circuit output or off-set an adverse condition caused by a change in viscosity of the control fluid.

Viscosity compensating circuits

A reversible regenerating drive system for a vehicle includes a constant speed, bi-directional motor which is energized by a source of power. The constant speed motor is coupled to a variable ratio transmission which in turn converts the output torque of the motor and delivers it to the vehicle to drive it in either forward or reverse directions at varying speeds. The transmission ratio and the direction of rotation of the motor are determined in accordance with signals derived from a pair of operator demand switches which are used to select the desired torque to be applied to the vehicle. The motor is arranged to generate power back to the source when torque demand is in a direction opposite to rotation of the motor. The direction of rotation of the motor is commanded to follow the direction of torque demand if the output speed of the transmission is below a predetermined value, but remains unchanged when torque direction changes if the output speed of the transmission is above the predetermined value.

Reversible regenerating electric vehicle drive

A vehicle propulsion system is provided with an auxiliary hydraulic drive having a variable displacement motor connected to ground engaging wheels by a clutch. A multiple position control has a first position which causes clutch engagement and positions a motor displacement member in a position which permits fluid drive of the motor. The control has a second position which causes clutch disengagement and positions the motor displacement member in a zero displacement condition which prevents fluid drive of the motor. Preferably the control is responsive to motor output speed and reduces motor displacement as speed increases.

Variable displacement hydraulic drive with disconnect

A control for a variable displacement motor which utilizes a motor speed sensitive signal for moving the displacement of the motor toward a zero displacement setting position including a device for generating a conditioned variable signal representative of motor speed, circuitry for receiving said signal and upon the signal reaching a predetermined intermediate value applying the signal to the control device for motor displacement for causing reduction in motor displacement and with various devices in the circuit for modifying the variable signal to provide a desired relation between motor speed and motor displacement. Utilization of such controls individually associated with plural variable displacement motors driving vehicle wheels and driven by one pump protects against spin-out of one of the wheels. The variable motor control is usable in a load-compensated system wherein at least one motor is associated with a drive at the front of the vehicle and another motor with the drive at the rear of the vehicle and with the control circuit having a valve responsive to the pressure condition in the system pressure lines connected between the pump and motors for differing adjustment of the displacement of the front and rear drive motors. The variable motor control is usable in a vehicle drive system with separate drives on the right and left-hand side of the vehicle to obtain steer compensation whereby the displacement of at least a pair of motors associated with the separate drives at the right and left sides of the vehicles are controlled by a circuit which includes a valve responsive to a steering signal whereby the displacement of the motors in their respective drives is varied to apply torque to the wheels in a relation to that required in connection with turning of the vehicle.

Controls for variable displacement motor and motors

A motor-nozzle coupling member for coupling a motor to a nozzle in an electro-hydraulic control structure wherein a linear electric motor having an armature is located at a fixed distance relative to the nozzle by a coupler which engages the motor and nozzle and extends therebetween to establish the spacing between the motor and nozzle and with the coupler being deformable after initial assembly to set the desired spacing.

Electro-hydraulic control structure

A three-mode, hydromechanical transmission including a pair of hydraulic displacement units forming a hydrostatic transmission and having a first, low-speed hydrostatic mode and a second and third intermediate and high speed hydromechanical modes. In one embodiment, a pair of planetary gear sets are related to form a four-element differential and are associated with an input shaft and the hydrostatic transmission and brake and clutch means. The hydrostatic transmission drives an output shaft through a connection to one of the planetary gear sets, with the brake means engaged. A first clutch means in a drive train from the input shaft to one planetary gear set effects the second mode of operation with the brake disengaged and a second clutch means in a parallel drive train to another element of the planetary gear sets effects the third mode of operation, with the brake and first clutch means disengaged. In another embodiment, three planetary gear sets are utilized to provide the same three modes of operation, with an extended third mode and with the brake means connected to an element in at least two of the planetary gear sets and with one of said drive trains also being connected to an element in more than one of the planetary gear sets.

Hydromechanical transmissions

A multi-mode hydromechanical transmission shift system having a hydrostatic unit with at least one variable and reversible displacement component with a displacement control, a plurality of clutches independently operable for setting the mode of operation of the transmission and a control circuit including a plurality of valves for setting the mode of operation and responsive to the position of the displacement control for causing a shift in operation from one clutch to the other to change the mode of operation.

Multi-mode hydromechanical transmission shift system

An engine-transmission control system having an engine associated with a variable hydrostatic transmission with a ratio governor valve to set the transmission ratio and, thus, control engine speed, a horsepower demand signal valve and an engine speed signal valve with the signals derived from these valves being applied in opposition to the ratio governor valve for control thereof, and an engine fuel governor for the engine providing an operating curve for the engine which relates engine speed to engine horsepower to cause operation along the locus of minimum fuel consumption for the engine whereby operation of the transmission to set the engine speed determines engine horsepower by operation of the engine along the operating curve. The system includes linkage means associating an accelerator pedal with the horsepower demand signal valve and the fuel control to provide a range of movement for the horsepower demand signal valve greater than that of the fuel governor, a lost motion connection in the linkage means which permits operation of the fuel governor in advance of the horsepower demand signal valve upon initial operation of the accelerator member, and second linkage means associated with an engine brake member for control of the horsepower demand signal valve without movement of the fuel governor and with relations between the linkage means whereby one linkage means may operate independently of the other.

Engine-transmission control system

A hydraulic transmission drive assembly having a pair of hydrostatic units mounted in a housing assembly for suspension from a primary housing and with the housing assembly supported on the primary housing by noise attenuation means including a pair of isolation mountings each of which are of a multi-layer construction with a plurality of plates for connection to either the primary housing or the housing assembly, with resilient material bonded therebetween and with mounting means extended through openings in said plates and surrounded by resilient material which is spaced from an opening in a center plate of the isolation mounting whereby axial loads result in compression of the resilient material and flexure of the plates and torsional and transverse loading results in shear of the resilient material under light loading and, under heavier loading, the resilient material surrounding the mounting means additionally acts in compression.

Hydraulic transmission drive assembly with noise attenuation means

An integrated transmission-engine control for a transmission, such as a hydrostatic transmission having a variable displacement unit connectable to an engine and a second displacement unit connected to an output shaft, including fluid pressure-operated ratio governor means for the transmission, fluid pressure-operated means for controlling the supply of fuel to an engine, a power demand valve for converting a particular power demand to a particular fluid pressure primary control signal. The primary control signal is applied to the ratio governor means in opposition to a signal representing engine speed to set the transmission ratio for a desired engine speed and also applied to the fuel supply controlling means to establish a fuel setting to match engine horsepower to engine speed for minimum fuel consumption.

Growing community of inventors

Ames, IA, United States of America

Frederic W Pollman