Showing papers on "Hydraulic machinery published in 1974"

Hydraulic energy storage transmission

Abstract: On a vehicle a hydraulic system to collect and to store energy upon braking of the vehicle the hydraulic system including an accumulator means, a hydraulic pump and motor means with the pump and motor means hydraulically connected together and mechanically connected to the vehicle wheels and the system including a reservoir of hydraulic fluid and conduit means to connect the reservoir and accumulator means and pump and motor means and operator means to selectively permit fluid flow in the system to store energy on braking of the vehicle and to release the stored energy to accelerate the vehicle.

Hydraulic propulsion system

Abstract: A hydraulic system for use in the propulsion of motor vehicles includes at least two volume multipliers each having a high pressure port, a low pressure port, and a piston in a chamber separating the high and low pressure ports A prime mover and associated main hydraulic pump is arranged to alternately supply high pressure fluid to the high pressure ports of the multipliers, so as to produce a reciprocating motion in the pistons and create a continuous flow of high pressure fluid from a reservoir through the pump, into the high pressure port of one volume multiplier, out of the high pressure port of the other multiplier, and back to the reservoir The reciprocating pistons are used to create a second, separate continuous flow of low pressure hydraulic fluid which circulates from the low pressure port of one volume multiplier through one or more hydraulic driving motors adapted to propel the vehicle, and back to the low pressure port of the remaining multiplier During deceleration of the vehicle, the prime mover may be turned off, whereupon the pistons no longer reciprocate Low pressure fluid is directed through a path that includes the driving motors, now acting as pumps, and a brake motor mechanically coupled to a regenerative pump connected in the high pressure system The latter is used to pump fluid from the reservoir into one or more accumulators disposed in the high pressure system, so as to store energy therein for later use

Suspension hydraulic roll stabilizer with leveling

Abstract: A suspension system for the sprung mass of a vehicle supported on wheels in which hydraulic struts are cross-connected across the vehicle for stability; each cross connection provided with a gas-charged accumulator providing a spring rate for each hydraulic system; and in which leveling of the sprung mass relative to wheeled supports is accomplished by selective transfer of hydraulic fluid between otherwise closed cross-connected strut systems. Use is for off-highway as well as on-highway trucks, wagons and other vehicles.

Determinants of systemic hydraulic power in unanesthetized dogs

Abstract: COX, ROBERT. H., Determinants of systemic hydraulic power in unawsthetizcd dogs. Am. J. Physiol. 226(3) : 579-587. 1974.-The characteristics of hydraulic power delivery to the systemic circulation by the left ventricle were studied in 16 trained, unanesthetized, chronically instrumented dogs. Measurements of ascending aorta flow, and ascending aorta, left ventricular, and central venous pressures were made under control conditions and during the injection of various neurohumoral agents. Cardiac output averaged 132 ml/min per kg at a mean arterial pressure of 98 mmHg and an average heart rate of 96 beats/min under control conditions. Total systemic hydraulic power averaged 7 13 mW with oscillatory power averaging 2Ooj, of the total. Norepinephrine increased total power to 935 mW with oscillatory power averaging 19%. Angiotensin produced no significant change in total power, but oscillatory power averaged 1 4y0. Isoproterenol increased total power to 1,129 mW with oscillatory power averaging 32 7& The oscillatory power fraction of total power was a strong function of heart rate under all conditions. Values of hydraulic fluid impedance for the ascending aorta were also calculated. Similarities of the impedance spectra for the various conditions were observed. The hydraulic power delivered to the systemic circulation as well as its components were found to depend on a) heart rate, b) left ventricular afterload (arterial pressure), and c) the inotropic state of the left ventricle.

Hydraulic system for a gang lawn mower

Abstract: A hydraulic system for a gang lawn mower of the type including a tractor having a hydraulic pump and valve and motors for driving the tractor A plurality of lawn mowers are mounted on the tractor and include cutters, and hydraulic motors drive the cutters The pump and the valve have separate sections for operating the respective motors, and the valve has spools which can be placed in various positions for operating the motors, and there is a single control assembly for positioning the spools to achieve operational position of the motors, including traction drive of the tractor at different speeds Hand levers and foot pedals are utilized for controlling the valve and the motors, and a lockout mechanism operates to preclude positioning of the valve in certain positions and thereby preclude placing the tractor in the transport mode when the mowers are operating, and vice versa The mowers are pivotally mounted on the tractor and may be raised and lowered through lifting cylinders connected to respective ones of said mowers, and a hydraulic sequencing valve permits raising and lowering of the mowers in sequence to assure proper mowing action

Arrangement for auto checking a hydraulic system

Abstract: An autochecking arrangement for a hydraulic system, which includes an actuating piston displaceable under the action of a pressure source and controllable as to displacement independently of the pressure of the pressure source by a valve arrangement, comprises a pressure sensor connected into the hydraulic system and emitting signals corresponding to at least two sensed pressure thresholds, a switching system for providing sequentially different actuation states of the hydraulic system and a monitor for monitoring the correct actuation of the hydraulic system in cooperation with the signals from the pressure sensor.

Electrical brake control system

Abstract: An electrical brake control system for a towed vehicle having an electric brake, where the control system is actuated by the hydraulic brake system in the towing vehicle. The electrical brake control system includes a hydraulic pressure transducer having a hydraulic input connected to the hydraulic brake system of the towing vehicle and an electrical output proportional to the hydraulic pressure developed by the hydraulic system. A comparator circuit has first and second inputs and an output. A circuit connects the first input to the electrical output of the hydraulic pressure transducer and a second circuit connects the output from the comparator circuit to the electrically operated brake in the towed vehicle. A feedback system connects the electrically operated brake to the second input of the comparator circuit such that the comparator circuit always maintains the feedback voltage to the second input substantially identical with the voltage of the first input.

Filtration for integrated tractor hydraulic system

Abstract: A hydraulic filtering and reservoir means to accommodate changing rates of hydraulic fluid flow through a variable displacement pump. A constant displacement pump and a variable displacement pump are used in the system to provide filtered pressurized fluid for hydraulic motors.

Hydraulic pile driver

Abstract: A fully powered hydraulic pile driver whereby maximum desired movement and positioning of leads is accomplished under full hydraulic power, thus simplifying the pile driver mechanism and providing positive and precise control to the operator. A hydraulically powered telescoping spotter is provided whose connections to the lead frame and rig are also fully powered. Power monks are placed in the lead frame for plumbing and positioning the piles. A single hydraulic power system is provided to operate all the powered components.

Hydraulic power transmission and braking system for vehicles

Abstract: A hydraulic power transmission and braking system for vehicles in which individual hydraulic wheel motors are connected through suitable control apparatus to a variable displacement hydraulic pump which is driven by an appropriate power source. The displacement of the pump varies automatically in response to hydraulic fluid pressure and flow rate requirements imposed by the vehicle operating conditions. The power transmission control apparatus automatically switches from the 4-wheel drive mode to the 2-wheel drive mode as the vehicle accelerates past a predetermined speed. The braking control system proportions the braking force applied to each of the hydraulic wheel motors in accordance with the load imposed on that wheel by the vehicle operating conditions.

Closed center hydraulic system for lift trucks

Abstract: A closed center hydraulic system is provided for a lift truck which includes an accumulator, a motor driven pump for supplying fluid under pressure to the accumulator, a plurality of closed center proportional electrohydraulic control valves for a plurality of hydraulically operated devices on the truck such as the lift jack, the mast tilt jack and the hydraulic powered steering mechanism. The pressure to the steering control valve is reduced by a pressure reducing valve and the pressure fluid supply circuit from the accumulator to the lift and tilt circuits is controlled by a blocking valve which is opened when the manual control member for either the lift or tilt control valve is moved from neutral to an operating position. Initial movement of either manual control member causes the blocking valve to open and further movement meters flow, thus permitting the operator to regulate lift and tilt speeds. A return line interconnects the lift jack and reservoir in bypassing relation to the lift control valve and a pilot operated bypass valve in the return line has its pilot line connected to one of the lift control valve delivery ports. An energy recovery system is disclosed in the return line from the lift jack.

Electrically modulated hydraulic-pressure regulating valve

Abstract: This disclosure relates to a electrically modulated regulation valve for hydraulic systems, said valve essentially comprising a slider-shutter of complex shape, whose length is considerable with respect to its diameter and is housed, along an appreciable fraction of its length, in an outflow channel, the latter being cylindrical with two different internal diameters and offering a guiding surface for the slider-shutter. The slider-shutter has a prolonged conical portion from which a cylindrical rod extends, having properly shaped projections which act as guiding members. The advantage achieved is a most accurate regulation of the hydraulic pressure.

Pressure compensated hydraulic accumulator

Abstract: The invention is a means for referencing the line pressure of a deep submergence hydraulic system to ambient pressure while allowing a shock absorbing accumulator gas charge to be affected only by shock loads in the system lines and not by changes in ambient pressure. A series of piston defined pressure chambers balance the system reference pressure with the ambient pressure and permit only the operating pressure differentials of the system to affect the shock absorbing gas charge.

Control system for hydrostatic drive tractors

Abstract: A control system is described for variable torque auxiliary hydrostatic drives for engine driven tractors having variable ratio mechanical transmissions. The system includes manually activated torque switch means for selection of either high or low torque hydrostatic drive operation and further includes transmission sensor means responsive to the selected ratio of the mechanical transmission and operatively associated with control means to automatically shift the hydrostatic drive from high to low torque operation when high torque operation has been selected and the mechanical transmission has been shifted to an intermediate ratio, and to automatically prevent all operation when the mechanical transmission is shifted to a high ratio. The control means is further responsive to pressure sensor means operatively associated with the hydraulic system and presettable to indicate a high hydraulic system pressure below which the control means shifts the hydrostatic drive from high to low torque operation and a low pressure below which the control means shifts the hydrostatic drive from low torque operation to off. The pressure sensors means also includes means for delaying the shifting from one mode of operation to another in order to prevent on-off and low-high torque cycling.

Auxiliary front wheel drive

Abstract: An auxiliary hydraulic front wheel drive including a pair of variable displacement pressure and flow compensated motors each connected to individual wheels; the auxiliary drive utilizes a pressure compensated pump source of the existing hydraulic system on the vehicle. The primary accessories run by said pump maintain a priority flow over the auxiliary drive motors since the pressure compensating level of the motors is set slightly below that of the pump.

Method and means for testing hydraulic pump

Abstract: The testing method and means of the present invention utilizes a conventional dynamometer for testing a hydraulic pump. The dynamometer is used to mechanically drive the pump and the hydraulic system of the dynamometer is used to supply the test pump with hydraulic fluid. A flow rater is connected to the tested pump for registering the pressure, flow rate, and temperature of the fluid being pumped by the test pump.

Simplified fluid circuit for shifting a transmission

Abstract: A hydraulic system responsive to movement of a shift lever actuates predetermined pairs of drive establishing devices in a vehicle transmission by applying a gradual fluid pressure rise to one such device to provide a selected drive ratio and by applying a delayed lesser gradual pressure rise to the other device of the pair to determine drive direction and to reestablish power flow through the transmission. The circuit also blocks fluid pressure from at least one of the pair of devices if the vehicle engine is started up with the control lever at a position other than neutral and neutralizes the transmission when the vehicle brakes are applied but maintains full fluid pressure at other vehicle components, such as the brakes, under both conditions. These functions including resetting at the beginning of each shift are all accomplished within a pair of selector valves, a pressure modulation valve assembly and a single spool safety differential valve in a compact, simplified and economically manufactured arrangement having a reduced number of separate components.

Vehicle and hydraulic fluid reservoir combination

Abstract: A hydraulic fluid reservoir is provided on a vehicle for containing fluid for use in the hydraulic system of the vehicle. The hydraulic reservoir is mounted between an upright wall forming a part of the vehicle operator's station and the backside of a water-cooled internal combustion engine. Coupled to the engine on the side remote from the reservoir is a blower-type fan. The reservoir is provided with a centrally located air duct means aligned with the engine and blower fan and the reservoir is so located that the engine-driven fan draws air around and through the reservoir to provide forced convection cooling of the fluid contained in the reservoir. The air duct means are so located relative to outlet and inlet ports of the reservoir that fluid flowing from the inlet to the outlet port will be deflected or baffled by the duct means.

Cleaning apparatus for overhead rails

Abstract: A cleaning apparatus for overhead conveyor rails particularly for meat packing plants having a traveler riding the rail and a cart moving below the traveler. The cart has tanks containing cleaning and oiling fluids; a hydraulic fluid reservoir; and a hydraulic pump driven by an electric motor. The traveler has a first brush driven by a hydraulic motor for scrubbing one side of a rail; a second brush driven by a hydraulic motor for scrubbing the other side of the rail; heads for spraying the rails with cleaning, rinsing, and oiling agents; grooved support-drive trolley wheels riding the rails and a hydraulic motor driving one trolley wheel. Lines between the cart and the traveler supply the traveler with agents and hydraulic power. A skin encloses the traveler containing spray and channeling used agents to a drain hose. A step-over mechanism supports one brush on the hanger-side of the rail and enables the brush to scrub closely to the hanger, move around the hanger, and re-engage the rail closely on the other side of the hanger. The cart has a hydraulic jack and the traveler has a socket receiving the jack shaft for lifting and lowering the traveler on rails. The traveler has mechanisms operated by the jack shaft which automatically disengages the brushes from the rail to facilitate mounting and removing the traveler on a rail.

Closed center hydraulic system with pump and accumulator output for high speed lift

Abstract: A single pump and a relatively large accumulator are used in a closed center hydraulic system for a lift truck to provide hydraulic pressure fluid for vehicle steering, load lifting, mast tilting and attachment operations. The operator may selectively utilize combined pump and accumulator output for high speed lift. This is achieved by pump contactor control means which the operator can selectively operate, when in the lift condition, independently of the pressure sensitive pump control means which automatically maintains the accumulator pressure between predetermined minimum and maximum pressures.

Apparatus for stroke control in high pressure machinery

Abstract: Apparatus for controlling the stroke of the movable member in a high pressure hydraulic machine, such as a hydraulic press, to permit the member to be positioned to an accuracy of 0.0005 inch and held at such position for a preselected time. The movable member is coupled to a piston movable within a cylinder which receives pressurized fluid. An adjustable threaded rod and nut arrangement is movable by movement of the piston within the cylinder, and an extension of the rod carries an actuating device for sequentially operating a first and then second valve. Operation of the first valve greatly reduces the speed of the movable member and operation of the second valve stops the movable member at its exact predetermined position. An adjustable time delay is coupled with the output from the second valve to maintain the movable member at such position for a preselected time thus maintaining the pressure on the article being formed in the machine. When the time delay expires, the apparatus and hydraulic machine are reset.

Apparatus for comminuting tree stumps

Abstract: Method and apparatus for comminuting a tree stump in its entirety while still rooted in the ground, utilizing a large, heavy cylindrical roller or drum rotating at high speed and having cutters mounted on a peripherical surface thereof for engaging and comminuting the stump from the side thereof. The roller is journaled for rotation about a horizontal axis in a carrier attached to the front end of a heavy four-wheel vehicle which is driven hydraulically over the ground surface from a selfcontained power source such as an internal combustion engine. The hydraulic system which drives the vehicle also includes a hydraulic motor mounted on the carrier for rotating the roller. The roller, through the carrier, is mounted to the vehicle frame for swinging movement in a vertical plane relative to the ground and a hydraulic cylinder included in the hydraulic circuit is provided for effecting said vertical swinging movement. Controls for operating the cutting roller and the vehicle are provided in an operator's cab on the vehicle.

Hydraulic tank reservoir pressure and vacuum stabilizer system

Abstract: An hydraulic system comprising a displacement-type hydraulic element in communication with a sealed reservoir tank for receiving hydraulic fluid from and returning hydraulic fluid to the reservoir, and a stabilizer for preventing excessive vacuum and pressure from forming within the reservoir as fluid is moved into and out of the same. The stabilizer is carried within the reservoir tank and has a bellows construction for compensating for change of volume in the reservoir as fluid changes take place therein, and the stabilizer is vented to the atmosphere through a breather system constructed to minimize entrance of dirt and the like within the stabilizer.

Car rock and roll hydraulic side bearing stabilizing arrangement

Abstract: Lateral rocking and rolling motion of a railway car body with respect to a supporting truck bolster is controlled and damped by truck bolster-mounted spring-loaded constant contact side bearings each enclosed to form a hydraulic chamber and each connected to the other through a normally closed pressure responsive valve device to provide a closed hydraulic system, the valve device being constructed to provide restricted passage of fluid from either side bearing to the other under predetermined rock and roll conditions.

Accumulator charging circuit for high pressure hydraulic system

Abstract: An accumulator charging arrangement for a high pressure hydraulic system. The arrangement includes a pair of relatively small volumetric capacity fixed-displacement pumps each of which is combined with a separate accumulator charging valve. The pump-charging valve combinations are disposed in parallel to feed pressure fluid to a pair of accumulator devices for use of the hydraulic circuit upon specific demand. One pump-charging valve combination supplies pressure fluid only within a certain pressure range. The second pump-charging valve combination supplies fluid at a second discrete pressure range which is higher than that within which the first combination operates. For system demands within a lower pressure range, both pump-charging valve combinations are operative to supply fluid, however, upon a demand for pressure only within the higher pressure range, only the second pump-valve combination is operative to supply the separate accumulator devices associated with the combinations.

Vehicle power steering electric circuit

Abstract: A power steering electric circuit having a hydraulic circuit and a flow-switch in the circuit and being electrically responsive to the flow of fluid in the hydraulic circuit. Two relay switches are electrically connected with the flow switch and are set in open and closed positions, according to the fluid flow through the flow-switch, and a third relay switch is included in the electric circuit and is connected with an electric motor for driving a hydraulic pump. Also, the ignition switch of the vehicle is connected with the electric circuit, all for the purpose of energizing the electric motor when the vehicle engine is not running, and thereby provide hydraulic power for the power steering unit of the vehicle.

Hydraulic system cavitation suppressor

Abstract: A cavitation suppressor for use in a hydraulic system, the cavitation suppressor serving to prevent excessive pressure in the system by bypassing hydraulic fluid around a mixing section to reduce the need for aspiration of additional fluid from a reservoir. The cavitation suppressor also prevents dissolved air in the system from coming out of solution. It includes inlet, mixing and outlet sections, and fluid bypass means communicating the inlet section with the outlet section.

Self-propelled vibratory compactor vehicle

Abstract: A self-propelled vibratory compactor has a one-piece frame supported at one end by a steel roller drum and at the other end by a yoke-mounted, single, high-flotation pneumatic rubber tire. The operator''s compartment includes a pair of laterally opposed operator''s seats at the opposite sides of the frame and is positioned on the frame over the pneumatic tire with steering, speed and directional controls positioned between the seats. An engine mounted on the frame behind and below the operator''s compartment, but forwardly of the roller drum, drives hydraulic pumps which supply fluid to a hydraulic vibrator motor which drives an eccentric shaft within the roller drum, a hydraulic wheel motor which drives the pneumatic tire, and a hydraulic power steering system for turning the yoke. The yoke spindle mounts a rotary seal which transmits fluid between a pump on the frame and the wheel motor on the yoke. A thin, narrow, rearwardly extending frame portion mounts the vibratory roller drum so as to provide the operator with good visibility of the ends of the drum when working close to curbs and other structures.

Hydraulic and mechanical no-cut earth working machine

Abstract: An earth working machine having both mechanical and hydraulic controlled equipment is provided with an electronic circuit to prevent the earth working implements on the machine from cutting buried metal objects such as communication cables, water pipes, and the like. When the electronic equipment detects when the earth working implements are near or contacting the underground object, both the hydraulic system is immobilized and the mechanical drive clutch disengaged. Provision is made to prevent the probe from acting as a radio antenna and, also, a seat switch is provided to disable the equipment should the operator be thrown from his operating position.

Relief mechanism for jaw crusher

Abstract: A relief mechanism for a jaw crusher which includes a hydraulic fluid filled piston-cylinder arrangement mounted on the frame and connected to the rear toggle of the jaw crusher. The hydraulic fluid is connected to a pressure sensor and a relief valve. The hydraulic fluid is maintained at a predetermined pressure during normal crushing operations. Upon encountering a material which cannot be crushed, the rear toggle transmits the higher than set pressure to the piston-cylinder arrangement thereby increasing the fluid pressure in the piston-cylinder arrangement. A pressure sensor senses this increased pressure and opens the relief valve to dump the entire hydraulic system. As the hydraulic system is dumped, the piston moves into the cylinder. The relief valve is sized so that the fluid is exhausted from the cylinder at a rate which allows unrestrained movement of the piston during relief. A positive stop on the piston-cylinder arrangement insures pressurizing of the system. An interlock with the crusher motor may be provided to shut down the crusher when tramp is encountered.