Showing papers on "Hydraulic machinery published in 1979"

Hydraulic system for transmitting power from an internal combustion engine to the wheels of a motor vehicle

Abstract: A motor vehicle engine is arranged to drive the vehicle wheels through a mechanical transmission, an hydraulic system including a variable-output, reversible, hydraulic pump, a variable-output hydraulic motor usable reversibly as a pump and a two-speed gear box. The outlet and inlet of the pump are reversibly connected by delivery and return conduits respectively, through a distributor, to the inlet and outlet of the motor and an hydraulic accumulator is connected through a closable valve to the delivery conduit, the operation of the system being controlled by a microcomputer so that when the vehicle decelerates at a rate greater than that due to natural resistance, kinetic energy which is normally lost in the engine is stored in the accumulator and can subsequently be reused to drive the vehicle wheels, the engine being cut out or maintained at minimum power. Excess power from the engine may also be stored in the accumulator and the engine is connected to drive the wheels through a direct mechanical transmission at high speeds.

Wind power conversion and control system

Abstract: A combination wind rotor and output energy transducer to provide output energy from the system and to automatically regulate the wind rotor at all wind velocities to thereby allow the wind rotor to operate at a constant tip speed/wind velocity ratio and at its maximum efficiency. The energy transducer is a combination of positive displacement hydraulic pump and an orifice in the hydraulic system to generate heat. Overspeed protection is afforded by maximum hydraulic loading of the wind rotor in extreme wind conditions. A wind rotor steering system by which the wind rotor is oriented into the wind at all wind velocities. The wind rotor restoring torque is automatically in balance with its reaction torque.

Speed responsive trailer stabilizer with zero slack

Abstract: A trailer stabilizer is comprised of a hydraulic assembly having a pair of hydraulic units for providing viscous fluid resistance to relative turning movements between a trailer and a towing vehicle The assembly includes flow controls for varying turning resistance in response to turning rate and vehicle speed Slack removal members constantly bias interconnected couplings to provide rate sensing and turning resistance with zero mechanical slack A brake control system actuates towed vehicle brakes in response to hydraulic system pressure and includes speed responsive components preventing brake application below a predetermined speed Circuitry is also provided for varying braking force in response to vehicle speed and turning rate, for adjusting braking force according to trailer size and road conditions, and for testing braking force adjustments

High pressure hydraulic system

Abstract: A high pressure hydraulic system, including a bidirec tional fluid motor having two ports, a pair of normally closed, pilot operated poppet valves, each connected to an associated port, a fluid reservoir, a flow sensor having a flow path interconnecting each of the poppet valves and the reservoir and having an output for providing a signal representing the flow rate, along the flow path, a pair of metering valves each connected to the pilot of an associated poppet valve for controlling the flow of fluid through the associated poppet valve, control signal inputs for each of the metering valves, and flow rate signal inputs connected to the output of the flow sensor for each of the metering valves so that each poppet valve is ultimately controlled by both control signals and the flow rate through the flow sensor.

Four wheel drive with automatic transmission

Abstract: PURPOSE: To permit automatic change-over from front wheel drive to four wheel drive travelling and vice versa while permitting automatic four wheel drive only in low speed high load advance by use of a hydraulic transfer clutch operated by line pressure in an automatic transmission. CONSTITUTION: Drive force from an engine is transmitted through an automatic transmission 3 to a front wheel final reduction gear 4 to drive normally front wheels while transmitted through a hydraulic system transfer clutch 35 to a rear drive shaft 31. The transfer clutch 35 is energized by line pressure generated in the automatic transmission at advance travelling to be automatically connected to the rear drive shaft 31 in high load advance necessary for four wheel drive. Since the transfer clutch 35 used is of hydraulic clutch, change-over to the four wheel drive can be carried out irrespective of travelling conditions and automatically in low speed high load running wherein the front wheels in advance are liable to lose relatively grip ability, so that performances of starting acceleration and running can be improved. COPYRIGHT: (C)1981,JPO&Japio

Lock valve with variable length piston and hydraulic system for a work implement using the same

Abstract: A lock valve (10) for use in a hydraulic system (90) for positioning the work implement of an earth working machine which includes first and second check valves (28, 30) and a piston section (60, 70, 62, 72) for each operable by pilot fluid. In a first mode, the piston sections (60, 70, 62, 72) permit seating of both check valves, while in a second mode, the piston sections interlock so that only one check valve can seat. The lock valve (10) operates in a hydraulic system (90) to lock a work implement, such as a blade for a motor grader, in a fixed position during a first operating mode, while providing a connection from one end of an implement actuator to vent during a second operating mode to insure that a shock absorbing means for the implement hydraulic system maintains a full shock absorbing capacity.

Hydraulic circuit for borehole telemetry apparatus

Abstract: A hydraulic circuit for borehole telemetry apparatus is presented wherein a mud pulse valve is operated by hydraulic pressure applied to differential areas of an actuating piston. The system includes a hydraulic pump, a filter in the line between the pump and the piston to be actuated, an accumulator upstream of the filter, a regulating and relief valve downstream of the filter, and solenoid actuated valves to control delivery of hydraulic fluid to the piston. The system also includes a pressure compensating bellows to compensate for changes in pressure in the drilling mud.

Fail-safe actuator and hydraulic system incorporating the same

Abstract: The present invention is directed to an improved fail-safe actuator and hydraulic system incorporating the same. The actuator includes energy storage means in the form of a spring adapted to set a control device in a predetermined condition, illustratively in the closed condition, responsive to a failure situation, illustratively, a power failure. The actuator includes a coupling which permits normal operation of the control device without cycling the spring energy storage means, thus increasing the life of the spring and eliminating energy wastage inherent in cocking the spring during each operative cycle.

Load sensing control for hydraulic system

Abstract: A load sensing hydraulic system is disclosed of the type in which a load signal is communicated from downstream of a main flow control orifice (33) to a device (29) which is operable to vary the fluid delivery rate in response to changes in the load signal. Disposed in the load signal conduit is a load signal modulating valve (37) which, in one position, communicates the load signal, substantially unchanged, to the variable fluid source. In another position of the modulating valve (37), the load signal chamber (29) of the variable fluid source is drained to tank (43), while in intermediate positions of the modulating valve (37), a portion of the load signal is communicated to the variable fluid source, and a portion is bled to tank (43). Modulation of a load signal permits flow control in an hydraulic system, independent of the position or movement of the main spool valve (15). The input to the modulating valve (37) may be manual or electric, and if electric, may be remote, or may be automatic in response to certain predetermined system conditions.

Constant pressure hydraulic accumulator

Abstract: A hydraulic system pressure fluid accumulator apparatus is disclosed that meets peak load demands beyond the flow capacity of the system pump. Gas cylinder actuation of the accumulator piston augmented by system pressure feedback actuation of the piston metered by a pressure regulator valve maintains accumulator output pressure level substantially independent of piston displacement.

Arrangement for actuating gas-change valves

Abstract: A hydraulic system for actuating gas-change valves in internal combustion engines or compressors wherein the output piston associated with each gas-change valve is capable of being moved against the force of a closing spring through a control circuit filled with control fluid by an input piston operable by a cam, with means for venting the control fluid at the highest point of the hydraulic system, and wherein the input cylinder communicates with a system for refilling with control fluid. The means for venting the control fluid are formed as permanent venting means, a variable area restrictor determining the amount of control fluid in the hydraulic system during operation is provided which is located in a discharge circuit, and the cam actuating the output piston is formed with a pre-ramp and a post-ramp.

Earth working implement control system

Abstract: An operating and down-pressure hydraulic control system for vehicle-mounted implements such as earth compactors and the like. The assembly of hydraulic cylinders, valving and a hydraulic accumulator provided herein operates as a hydraulic system to raise, lower and otherwise position an implement and to provide down-pressure to it. The assembly also permits the hydraulic support of the implement to flex, while maintaining down-pressure on it, when the ground surface elevation rises or falls away relative to the implement as it moves over the ground being worked.

Hydraulic valve for two-speed power take-off drive

Abstract: A hydraulic valve for a two-speed power take off selectively operated by a reversible stub shaft providing the proper output drive.

Hydraulic braking system

Abstract: Three embodiments of a hydraulic braking system are shown and described. Each embodiment provides a precisely controlled hydraulic braking system for a railway vehicle, which features a pilot pressure controlled brake control valve. The pilot pressure is selectively varied by operation of pressure control and flow control valves so that the power requirements for the hydraulic braking system are minimized. The braking system can be used with either spring-apply, pressure-release or pressure-apply, spring-release braking actuators. An auxiliary hydraulic system is provided to operate the brakes if the primary hydraulic system should fail. The pilot pressure fluid which operates the brake control valve can be either hydraulic or pneumatic. The brake control valve can be provided with a pneumatic emergency brake override control.

Hydraulic bedknife adjuster for reel-type mowing equipment

Abstract: A hydraulically-actuated bedknife alignment and positioning mechanism which uses the hydraulic power source to precisely adjust the distance between the blade of a reel-type lawn mower and the bedknife for proper cutting action. The system includes a source of hydraulic fluid under pressure, a hydraulic cylinder (mounted to the frame of the mower) which houses a piston connected by a linkage arm to the bedknife that is biased relative to the reel blade and attached pivotally to the frame. During adjustment, the cylinder is pressurized, forcing the piston to move the bedknife into contact with the blades of the mower. When the hydraulic pressure is removed, the biasing force pushes the bedknife away from the reel blade, but a hydraulic locking valve in the actuating cylinder line limits precisely how far the bedknife is biased away from the reel blade before sealing shut, effecting proper distance setting. The hydraulic adjustment may be remotely actuated by the operator of the mower.

Vehicle emergency steering system

Abstract: An emergency or backup steering system includes a backup pump which is driven by an electric motor. A control circuit for the motor automatically energizes it upon the main supply of hydraulic power steering fluid becoming inadequate for normal steering operation. The control circuit provides for checkout of the portions thereof governing actuation of the backup system and provides for indicating failure in the backup system of both the electrical and hydraulic portions thereof.

Automatic volume control system

Abstract: An automatic volume control system for controlling the rate at which fluid, such as paint, is sprayed from spray guns on a mobile vehicle as a function of vehicle speed. The device permits paint lines to be maintained at a uniform thickness independently of the vehicle speed. A tachometer generator generates a voltage proportional to the vehicle road speed which voltage controls the opening of an adjustable hydraulic valve. Hydraulic fluid passing through the hydraulic valve drives a hydraulic generator which in turn drives a spray gun system. The voltage from the tachometer generator thereby causes the hydraulic fluid to drive the hydraulic motor and paint pump at a rate which is proportional to the vehicle road speed. The hydraulic fluid is suitably pumped through the hydraulic valve to the hydraulic motor by a hydraulic pump driven by the power take-off of the vehicle. By using a flow divider valve connected between the hydraulic pump and the hydraulic motor, two separate and parallel independently controllable painting systems may be provided. An intermittent line mechanism powered by the vehicle road wheels, is connected to the spray guns and to hydraulic motor bypass valves in order to provide line patterns which are independent of vehicle road speed.

Hydraulic valve system for controlling particularly a vehicle gearbox

Abstract: A hydraulic valve system for controlling operation of a motor vehicle gear box comprising a plurality of multi way valves of the disc-type in which the first multi way valve conveys pressure fluid to either one of two consumers and drains the consumer to which fluid is not conveyed, one of the two consumers comprising a valve system having two or three of the said multi way valves, each of which is operable to supply pressure fluid to one or other of two further consumers, and means to interlock the said two or three multi way valves so as to permit connection to only one of four or six consumers at any one time.

Concrete mixing apparatus

Abstract: A concrete mixing machine is disclosed which mixes small batches of concrete using any desired ratio of gravel, sand, cement, and water. The dry materials are mixed into concrete at the site where the concrete is to be poured. The apparatus includes hoppers for storing the dried mix material, a water tank, a metering slide for measuring desired amounts of cement, sand, and gravel to the desired proportions; a mixing, feeding, and dispensing system; and a hydraulic system for driving the mixing apparatus. The hydraulic drive system is utilized to overcome the binding which occurs when residual concrete begins to set.

Heating system comprising a heating pump

Abstract: In a heating system comprising a heating pump with a compressor (7) of a heating pump circuit, which compressor can be driven via coupling means using the energy of a combustion engine (1), the coupling means are formed by a first hydraulic or electric machine (2) which is coupled to the combustion engine (1) and can be operated as generator or pump, and by a second electric or hydraulic machine (6) which is coupled to the compressor (7), operated as an engine and which can be coupled to the first electric machine or first hydraulic machine only electrically or hydraulically but not mechanically.

Hydraulic power brake system and hydraulic brake booster and controls therefor

Abstract: A hydraulic pressure actuated power brake system having a hydraulic power booster with operating pressure on both sides of the power piston power wall The booster is therefore hydraulic pressure suspended so that the hydraulic pump of the system need not be operating to maintain this pressure while the booster is inactive An accumulator is also charged by this pressure to provide power brake booster operation for several booster actuations without recharging by the pump When the pump is operating, a pilot valve which is sensitive to a drop in booster operating pressure will control charging or recharging the accumulator and booster from the pressure generated by the pump to maintain a desired charge pressure A pressure relief valve will also prevent overcharging of the accumulator and booster A check valve prevents loss of booster operating pressure toward the pump outlet if the pump pressure falls below the charged pressure A spool control valve in the booster modulates pressure on the downstream power piston side, returning fluid to the pump reservoir and creating a controlled pressure differential across the piston power wall to actuate the booster A mechanical follow-through is provided for manual operation when booster operating pressure is depleted

Constant flow hydraulic system

Abstract: A variable displacement pump (56) is compensated to provide a relatively constant predetermined flow of hydraulic fluid under pressure to an opencenter hydrostatic steering system (52) as the speed of the engine driving the pump (56) varies, and a reliefvalve (88) by-passes the steering system (52) whenever the steering system (52) would normally reduce the flow to hydraulic apparatus connected in series with and downstream of the steering system (52).

Hydraulically operated access equipment

Abstract: Hydraulically operable access equipment, usually but not necessarily vehicle mounted, and of the kind comprising a boom structure consisting of a plurality of booms pivotally connected together in end to end relationship, hydraulic actuators with an associated hydraulic control system for moving the boom structure between a stowed position wherein at least some of the booms lie parallel with one another in a substantially horizontal direction and an extended position wherein the free end of the boom structure is raised to an elevated position, characterised by the provision of secondary, normally closed, inlet and outlet ports to the oil chambers of at least some of the hydraulic actuators, and an auxiliary system comprising a pump and flexible hoses capable of being extended from such pump for connection to the secondary inlet and outlet ports of each said actuator, whereby such actuators may be operated to permit movement of the boom structure to its stowed position by use of said auxiliary hydraulic system.

Fluid motor-pump unit

Abstract: A fluid motor-pump unit having a circumferentially arranged set of pistons axially reciprocal within a stationary cylinder block, and a rotating valve plate for sequentially porting the pistons between high and low pressure hydraulic ports of an hydraulic system. Apparatus and method are disclosed for dynamically pressure-balancing the rotating valve plate for low friction and low wear operation.

Pressure modulating valve

Abstract: A pressure modulating valve 28 has a principal use for retrofitting into an original hydraulic system (10) to modulate the fluid pressure from a source (11) of hydraulic fluid to hydraulic clutches (50, 52) in a transmission (54) In prior art valves, the routing of hydraulic fluid from the original system to the valve involved the connection of many lines The present invention is connected to the source (11) at only one location and discharges fluid to the clutches from said location The valve (28) is operated by the fluid provided at the one location without the need to route fluid around the valve (28) to the various components thereof The valve (28) also modulates the fluid supplied to the clutches from a low pressure to a high pressure to provide smooth clutch engagement

Mobile spreader apparatus drive system

Abstract: A mobile wheel mounted spreader apparatus has a material feed conveyor and a broadcast spreading impeller fan. A wheel driven drive train operates through a gear reducer to drive the conveyor at a speed proportional to the towed speed of the spreader apparatus and operates through a hydraulic system, to drive the impeller fan at a constant speed regardless of variations in the towed speed of the spreader apparatus.

Coaxial coupling system

Abstract: The invention relates to a coupling system for coaxial hoses adapted to feed fluid into hydraulic machines and apparatus and to provide an exit for same, such a system ensuring conveniently and speedily under good operative conditions, a disconnectable fitting of the ends of the input and output pipes respectively on a body such as a union connected in its turn with a supply of a compressed fluid, and with a handtool such as hydraulic shears or pruning-scissors or else a machine-tool such as an air-hammer or a hydraulic machine, to be used on the yard.

Hydraulically damped railway car body roll

Abstract: An arrangement for controlling car body roll in high capacity railroad freight cars, in accordance with which a hydro-pneumatic roll contact unit is incorporated in the car truck spring groups that support the respective truck bolsters. The roll control unit comprises a base housing defining a lower or outer cylinder having an upstanding piston rod structure equipped with a piston head that reciprocably mounts a tubular ram having a ram head that operates in the outer cylinder and defines an upper or inner cylinder in which the base housing piston head operates. An annular rolling seal is received in circumambient relation about and connected to both cylinders invaginating leak free relation thereto, which defines an annular reservoir about said cylinders with which both cylinders have communication. The cylinders and the reservoir are given a hydraulic liquid charge sufficient to fully fill the two cylinders and the lower portion of the reservoir, and a gas charge within the reservoir that forms a pressurized gas pocket above the level of the hydraulic liquid charge in the reservoir. The gas charge maintains the unit in constant contact with the bolster and side frame seats. In functioning to control body roll, both cylinders resist roll under constant pressure conditions while the outer or lower cylinder provides supplemental resistance under velocity sensitive conditions, with the hydraulic liquid cycling through the hydraulic system of the unit as the unit operates as part of a bolster spring group.

Shaker chain drive assembly for tomato harvester or the like

Abstract: The drive unit of a conventional mechanically actuated shaker for removing comestibles from their support vines is supplanted by a pair of hydraulic motors capable of effecting extremely rapid forward and reverse movement of the shaker. An adjustable multivibrator circuit produces electrical pulses of predetermined duration and frequency. The pulses activate a solenoid-operated hydraulic valve supplying first the forward motor and then the reverse motor with hydraulic fluid. The quick, snapping action of the shaker afforded by the electro-hydraulic drive apparatus effectively denudes the plants or vines of their fruit.

Hydraulic load lifting system with automatic blocking valve

Abstract: In a hydraulic system (10) comprising a check valve (33, 34) with a main line (27) and a vent line (69), the improvement includes blocker means (100, 104) for closing said vent line (69) when the pressure in said main line (27) falls below a predetermined level. In prior art hydraulic systems, and in particular in hydraulic systems having a cylinder means for elevating and lowering a load, there exists the possibility that the hydraulic line from a control valve to the cylinder means could rupture, allowing the load to drop before the operator could react. The present invention solves this problem by providing a blocker valve (100) in the vent line (69) of a check valve (33, 34) which check valve is interposed in the main line (27) between a cylinder means (12) and a control valve (21). The blocker valve (100) is responsive to the back pressure in the main line (27) from the check valve (33, 34) to the control valve (27). Thus, when the pressure in said main line (27) drops below a predetermined level due, for example, to a break in said line (27) the blocker valve (100) automatically closes the vent line (69), preventing the check valve (33, 34) from releasing hydraulic fluid, and thus preventing the load (14) from dropping. In an aspect of the invention, a resolver valve (104) actuates the blocker valve (100). The resolver valve (104) communicates with the main line (27) at two positions and selects the lowest pressure between said positions.