Showing papers on "Hydraulic machinery published in 1971"

Electrically operated hydraulic valve particularly adapted for pollution-free electronically controlled internal combustion engine

Abstract: An electrically operated hydraulically driven valve driven by internal combustion engine lubricating oil A ported valve sleeve is positioned between inner and outer cylinders, the inner of which is the hydraulic valve operating cylinder All concentric members have radial ports The electrically operated sleeve member controls the porting controlling the inflow and outflow of hydraulic liquid The control sleeve is moved electromagnetically by way of electromagnetic windings combined with a permanent magnet adapting the operation to pulse type of digital control adapting the valve to electronic digital control from multiple variable inputs

Hydraulic power trim and power tilt system for a marine propulsion device

Abstract: Disclosed herein is an outboard motor including a first extensible hydraulic cylinder means pivotally connected between a transom bracket and a swivel bracket to afford power tilting and, in response to the striking of an underwater obstacle, to afford energy absorption, together with a second extensible hydraulic cylinder means having an extensible part and mounted on the transom bracket with the extensible part positioned for engagement with the swivel bracket to afford trim adjustment. The disclosed outboard motor also includes connection of the first and second extensible hydraulic cylinder means in parallel relation to an electrically operated reversible hydraulic pump and further includes an electrically operated normally closed valve controlling communication between the trimming hydraulic cylinder means and the hydraulic pump independently of the communication between the tilting hydraulic cylinder means and the hydraulic pump, together with a tilt control switch operable to actuate the hydraulic pump, and a trim control switch operable to actuate the hydraulic pump and to open the normally closed valve.

Control system for a stepless hydrostatic drive

Abstract: A hydrostatic drive has a pump driven by a prime mover, e.g., an internal-combustion engine, and connected in a substantially closed hydraulic power circuit with a hydraulic motor connected to a load. The hydrostatic drive may be used, for example, to power a vehicle or an accessory or appliance of the vehicle. The hydrostatic pump-motor system has a control member shiftable to vary the speed of the system in a stepless manner and operated by a servocylinder from a pilot valve which, in turn, is controlled by the pressure in a pair of pilot lines. A speed governor or sensor responsive to an overload of the engine, automatically acts upon the pilot valve to reduce the speed in the vent of a torque overload.

Hydraulic power translating device

Abstract: A hydraulic power translating device of the gerotor type having inner and outer rotatable partially meshing gear elements with a pressure fluid passage surrounding a major part of the exterior periphery of the outer gear element to obtain radial balance of the outer gear element upon start up in motor operation and with a plurality of recesses formed in the case of the device and at the cross-over areas which operate as fluid accumulators of limited capacity to reduce the noise of operation of the device as well as torque variations and to compensate for tolerance and natural frequency variations in the mechanical structure and to also axially balance the gear elements.

Hydraulic flexion control device

Abstract: A hydraulic knee flexion control device which when unlocked is completely flexible and free to align with the knee joint axis It is comprised of a rectangular cross-section spring wound tight with a flexible cable positioned in the center of the spring A hydraulic system holds the cable immovable when the joint is to remain rigid and lets the cable extend thus permitting the spring to bend when flexion is desired

Vehicle hydraulic braking system

Abstract: An anti-skid hydraulic braking system is disclosed which comprises a monitoring device responsive to the angular displacements of the wheels of the vehicle for controlling the fluid pressure level applied to a pressure modulator which in turn controls fluid communication between a standard automotive master-cylinder and the brake motors. The monitoring device is supplied with pressurized fluid from the pump of the general hydraulic system of the vehicle. Upon failure or malfunction of the pump, it is necessary to prevent the monitoring device from terminating fluid communication between the master cylinder and the brake motors which would prevent any further brake application. A control means is provided in the pressure modulator which comprises, in a chamber connected to the outlet of the pump, a reciprocable spring loaded piston which maintains the fluid communication between the master-cylinder and the brake motors when the pressure of said pump falls below a predetermined value.

Endless track vehicles

Abstract: An endless track vehicle, including a frame, a body on the frame, a pair of endless tracks, independently operated, so that each track can operate at varying speeds, and even in reverse to one another, a closed hydraulic system including connecting pipes to and from a fluid tank, an hydraulic pump, driving fluid to two two-way hydraulic control valves leading to two reversible hydraulic motors each separately driving a track, a gasoline powered engine having a shaft attached to the crankshaft. A modification includes the same mechanism in which the body is divided into two separate longitudinal sections, each supporting an endless track, and is connected by independent suspension means so that each track is independently mounted to permit the track to separately conform to irregularities in the terrain.

Closed center hydraulic system

Abstract: A closed center hydraulic system having a variable displacement pump, two or more motor circuits associated therewith, one circuit being of the proportional demand type, priority means assuring the power requirements of said proportional demand circuit are met prior to permitting power flow to the other circuit, and flow and pressure compensating means in the other circuit for controlling the displacement of the pump.

Snubber seal leakage test circuit

Abstract: The hydraulic system of shock suppressor apparatus for vapor generators utilized in nuclear power plants is provided with integrated fluid circuitry that permits testing for leakage across internal piston seals to be conducted in situ. The fluid circuitry, together with appropriate valving, is operative to hold the piston members of the shock suppressor apparatus in place while testing is conducted and to impart fluid pressures to the system that simulate maximum piston loadings. Sight glass or other detection apparatus is utilized to determine the presence of a leak.

Cooled hydraulic system

Abstract: A hydraulic system which includes bypass restrictors at the extremities thereof to produce a predetermined flow of hydraulic fluid in selected hydraulic lines. The predetermined flow of hydraulic fluid transfers heat generated in the system throughout the system so that the heat loss along the hydraulic lines is sufficient to maintain the temperature of the hydraulic fluid below a predetermined temperature.

Effect regulator for constant and variable volume-flow pumps

Abstract: Means for regulating the flow of fluid from two or more pumps in a hydraulic system, according to the instantaneous demand for energy.

Automatic pressure relief and snubbing in hydraulic actuators

Abstract: Rapid start-up acceleration is automatically attained by pressure relief provided for the discharge chamber through a dump valve referenced to the drive chamber of the actuator. Deceleration is accomplished by snubbing hydraulic fluid discharge and by diverting pressure directly from the hydralic feed line. Negative pressure relief or anti-cavitation is provided for in the hydraulic system of the actuator. A novel, efficient snubber valve is carried by the actuator piston to control hydraulic fluid passing through the discharge port of the actuator.

Hydraulic power brake booster

Abstract: A hydraulic power brake booster powered by power steering gear pump pressure and utilizing an open-center valve so that fluid flows through the booster without pressure reduction when the booster is not activated. The valve assembly includes a radially floating valve seat which provides for self-centering, permits a valve separation operation to pass viscous cold hydraulic fluid or any elements which may tend to overly restrict the valve. It also includes a valve face design providing entrance and exit angles defining a venturi-type passage conductive to laminar flow with consequent reduction in valve noise, and has a hydraulic reaction mechanism which includes an arrangement for supported line pressure.

Apparatus for aiding disposal of snow by compacting it to great density

Abstract: Snow is dumped into a portable compressor which compresses the snow by hydraulic power through three stages into blocks of great density which require much less space than the original show and can hence be carried away with greater economy, or piled up with less commandeering of usable space. Hydraulic strokes are controlled by limit switches. When sufficient density is achieved in the final stage, the hydraulic pressure trips a switch which opens a gate so that continued cycling of the compacting apparatus ejects a highly compacted block of snow. When far enough out, it trips a switch to cause the gate to close, shearing off the projecting block, and dropping the block onto a conveyor. The combination of a swinging guard and pusher plate jointly forming one wall of the hopper permits handling huge quantities of snow.

Method of manufacturing a motor vehicle

Abstract: A method of manufacturing a motor vehicle including manufacturing a subassembly comprising a frame cross member, a front suspension system, a steering linkage system, power steering gear system, front brake system and power brake booster system integrated into a single unit. The method includes the adjustment of the suspension and steering linkage components for obtaining proper wheel alignment and the charging of the hydraulic systems of the power brake booster and power steering booster with hydraulic fluid prior to the installation of the subassembly into the vehicle body.

Hydraulic spring brake control system

Abstract: A vehicle hydraulic braking system is disclosed which includes a hydraulic brake booster which operates a standard automotive master cylinder. Disc brakes which include a hydraulic service actuator and spring-applied parking actuator are mounted on at least two of the wheels of the vehicle. Pressurized fluid from a hydraulic source, such as the vehicle''s power steering pump, is used to operate the brake booster when a service brake application is effected. The spring actuator on each of the disc brakes includes a pressure responsive device that opposes the resiliency of the springs. Fluid is communicated from the booster pressure chamber to the pressure responsive device when the engine of the vehicle is started and the first brake application is effected to release the spring actuator. A control valve is provided so that fluid may be purged from the pressure responsive means when the vehicle is parked or when an emergency occurs. The fluid pressure from the booster pressure chamber is communicated to a pressure intensifier which increases the fluid pressure level that is provided to the pressure responsive means. The pressure intensifier includes a manually operated device to release the spring brake when a malfunction in the vehicle''s hydraulic system prevents fluid communication to the booster pressure chamber.

Dual network hydraulic brake system

Abstract: A hydraulic brake system for motor vehicles in which a master cylinder having two chambers is operably connected with a brake pedal. A plurality of wheel brake cylinders and a dual network hydraulic system connects the two chambers of the master cylinder with the wheel brake cylinders. A pressure regulator valve of a dual piston type is provided in the network and carries a movable contact for actuating an alarm device to indicate to the driver of an operational failure in the hydraulic system.

Hydraulic system failure detectors

Abstract: Hydraulic system failure detector including a sensor in a high pressure drain line connected between possible sources of excessive pressure or flow and a drain. The sensor includes a restriction capable of passing limited flows and of relieving limited pressures. It also includes a damped, pressure-operated bypass valve in parallel with the restriction. Relief valves in branches of the high pressure drain line isolate the failure sensor from normal high pressure in those lines until the occurrence of overpressure resulting from a failure thus to permit detection of failures characterized by widely differing fluid pressures while permitting calibration of the detector at the pressure of the lowest failure pressure.

Hydraulic system for a loader

Abstract: A hydraulic system for a loader having a typical lift arm and a typical bucket pivotally mounted from the lift arm, and which hydraulic system includes in the principal embodiment three pumps, valves and related conduits for directing the hydraulic fluid in such a manner that when the lifting load resistance is above normal during lifting movement of the lift arm, the fluid first automatically causes a roll back motion of the bucket to try to relieve the abnormal resistance and then, if not relieved, the fluid causes the transmission disconnect to function to disconnect the power of the engine from the loader''s wheels or tracks to stop the movement of the loader. A shuttle valve is provided in the circuit to prevent ''''chattering'''' during the bucket dumping operation. In addition, this system includes a steering control arrangement whereby at low speeds of the engine, the output from two of the pumps will flow to the steering valve and at higher speeds the output from one of these two pumps will be directed to a pilot operated valve where the pressure is utilized in combination with the third pump in the implement circuit. A second embodiment is disclosed which utilizes only two pumps and the steering arrangement is not in combination therewith.

Texture and acoustic spraying equipment

Abstract: This invention is directed to texture and acoustic spraying equipment for spraying texture material on walls and acoustic material on ceilings. This spraying equipment comprises one prime mover for driving a first hydraulic pump and also for driving an air compressor. In turn, this first hydraulic pump drives a hydraulic motor for agitating the texture material and the acoustic material. Further, this first hydraulic pump drives hydraulic motors for driving hydraulic pumps for pumping the texture material and the acoustic material to the pneumatic spray gun.

Dual fluid supply circuit for a power steering and a hydraulic power brake

Abstract: An automotive hydraulic circuit containing a power steering and a power brake, a main pump for normally forcing fluid circulation in the hydraulic circuit and an auxiliary pump for forcing the fluid circulation when the main pump fails to discharge sufficient flow.

Device for automatic thickness control of rolled strips

Abstract: A device for automatic thickness control of rolled strips which ensures an accuracy of the rolled material from + OR - 0.002 mm to + OR - 0.003 mm, does not call for major capital expenses and long stops of the rolling mills for its introduction and is characterized by high operating reliability and simple servicing. The device for automatic thickness control of rolled strips in installations for the manufacture of strip materials, comprising symmetrically located on both sides of the roll stand at least one hydraulic power cylinder installed between the supports of the working rolls, a damping hydraulic cylinder whose piston is fixed while the strip is passing through the roll stand, and a controllable valve connected so that the hydraulic system formed by said hydraulic cylinder and valve is closed and creates a local increase in the rigidity of the roll stand within the range of forces which is approximately equal to the range of variations of the rolling pressure from the preset value. The device has a positive feedback circuit actuated by the fluid pressure in the closed hydraulic system, this circuit comprising a pressure meter in the hydraulic power cylinder, an element for comparing the measured deviation of pressure with the value proportional to the preset coefficient of positive feedback, connected with the pressure meter, and an actuating element connected to said comparison element and to the correcting element made in the form of a hydraulic cylinder communicating with the hydraulic power cylinder.

Hydraulic power brake unit

Abstract: A hydraulic power brake unit including a power piston operatively engaging a conventional master cylinder and an annular valve spool having differential end areas communicating with the power chamber formed by the power piston and being normally positioned in the housing to communicate hydraulic fluid from a pressure source to the power steering unit and communicate the power chamber to the power source reservoir. When the brake pedal is actuated, an actuating spring acting between the valve spool and a reaction piston attached to the pedal pushrod is compressed and the valve spool is moved to restrict fluid communication from the pressure source to the power steering unit and divert the flow to the power chamber while simultaneously blocking communication of the power chamber to the reservoir so that the power chamber is pressurized and the power piston fluidly displaced to actuate the master cylinder. The power chamber pressure acts on the differential area of the valve spool to resist its movement by the actuating spring and causes it to function as a regulating valve which continuously provides a power chamber pressure proportional to the force of the actuating spring. Upon a malfunction caused loss of hydraulic pressure the reaction piston moves into abutting engagement with the power piston to provide a rigid force transmitting link between the pushrod and the master cylinder whereby the brakes are actuated independently of the hydraulic boost.

Power steering system affording emergency steering capability

Abstract: The disclosure concerns hydraulically operated power steering systems for vehicles, particularly large articulated vehicles. The system includes a closed center steering valve which normally is supplied with oil from an engine driven pump, and it incorporates an accumulator and a ground drive pump which provide sufficient hydraulic power to permit steering during extended periods of engine-off towing.

Rotary hydraulic machines

Abstract: A rotary hydraulic machine has a rotor journalled on a pintle which extends internally of the machine casing. The rotor has an axial bore into which the pintle extends so as to provide a space between the end of the pintle and the end of the bore. Fluid pressure within the casing is admitted to this space to partially offset the pressure urging the rotor onto the pintle.

Hydraulic valve with leakage control

Abstract: A hydraulic valve of the spool type with means to trap hydraulic fluid which tends to leak between the spool and the bore of the valve in which it slides and to bypass said fluid to atmosphere or a tank in order to prevent it from flowing past the spool to actuate a hydraulic motor causing it to move or creep when it should be at rest.

Hydraulic system for single engine truck crane or the like

Abstract: A hydraulic system for a single engine truck crane includes a pump input section in the carrier that is driven by the carrier engine and an output section in the upper works A closed loop connects the input and output sections and requires only two passages through the swivel joint The working reservoir is in the upper works, and a supercharge pump in the upper works is driven by the output section and draws from the reservoir to feed the loop In one embodiment the output section comprises a flow divider leading to valve units and working motors which are incorporated in the closed loop, and in another embodiment the output section includes a power motor which is driven by the pump in the carrier and which drives working pumps in the upper works that serve the working motors

Motion transmitting apparatus

Abstract: Apparatus of the rack and pinion type of hydraulic actuator having low back-lash and friction for converting hydraulic power by a linear to a rotary motion mechanism employing valved hydrostatic lubrication means responsive to the hydraulic pressure to hydraulically support and lubricate the rack with respect to a rack supporting bearing and employing as the lubricant the hydraulic fluid used for transmitting the power

Weight transfer hitch

Abstract: An electrically controlled hydraulic cylinder having a variable resistor and a bridge circuit for preselecting the desired length of a remote hydraulic cylinder in the hydraulic system of a tractor

Power control winch

Abstract: A winch having an integral control system wherein the clutch and brake mechanism are hydraulically actuated and the hydraulic actuating system is positioned in the winch housing. The system includes the oil supply, the control valve, the hydraulic pump and an accumulator. The pump is self-compensating and is mounted to be continually actuated by a shaft in the drive train to the winch drum. To reduce the volume of hydraulic fluid normally required in a hydraulic system and to improve the reliability, the valve is a unique no-leak type with the inlet through a bore in the valve spool and an outlet located along only one side of the spool and the valve is used in conjunction with an accumulator which allows release of the brake after shut down of the drive train. The brake mechanism comprises multi-wrap brake bands which are spring-actuated and hydraulically released, the multi-wrap enables relatively high braking force produced by a minimal spring actuating force.