Abstract: An electric-powered fail-safe actuator for use with a valve, where the actuator stores potential energy for conversion to kinetic energy to close or open the valve to the fail-safe position.

Abstract: A control system for a subsea blowout preventer (BOP) positioned in a lower stack, the lower stack releasably engaged with a lower marine riser package (LMRP). The control system includes a surface logic solver positioned at or adjacent the surface of the sea that generates commands for operating the subsea BOP, a first subsea logic solver attached to the LMRP and in communication with the surface logic solver so that the first subsea logic solver receives the commands from the surface logic solver, and a second subsea logic solver attached to a hydraulic control unit in the lower stack. The second subsea logic solver is in hydraulic communication with the subsea BOP, and the first subsea logic solver so that the second subsea logic solver receives the commands from the first subsea logic solver and implements the commands by activating the hydraulic control unit to operate the BOP.

Abstract: A fail-safe actuation system comprising an actuator having first and second chambers, a working circuit with a motor/pump device configured to actuate the actuator in an operative state, and a safety circuit configured to move the actuator into the safety position in a failure state, the safety circuit having a tank that holds pressurized fluid and that, in the failure state, is automatically connected to the first chamber via a switching valve, and having a drain valve that, in the failure state, is moved into a through-flow position in order to drain fluid out of the second chamber, the safety circuit configured such that, in the operative state, an inflow into the actuator—in a manner that is decoupled from the tank—is established by the working circuit, and, in the failure state, an inflow from the tank into the first chamber—in a manner that is completely decoupled from the working circuit—is created by the safety circuit, whereby a short-circuit fluid connection is provided between the first and second

Abstract: Disclosed is a fail-safe fluidic actuation system (1) having a safety position, comprising a control element (2) having at least one first and one second chamber (3, 4); having a working circuit (5) with a motor/pump device (6), wherein the control element can be actuated by means of the working circuit at least in the operational state.

Abstract: When an excitation of a servo motor is released due to an emergency stop, a power outage, or another operation performed on a positioning device, the positioning device uses air supplied from an air supply source to vary pressure of an air balance, which cancels a self-weight of a vertical axis driven by the servo motor, thereby moving the vertical axis.

Abstract: A fail-freeze valve positioner system is disclosed. The system has a transducer with a first type output port connectible to a valve actuator, and a second type input port receptive to a valve position signal that is proportional to an output of the first type output port. In addition, the system has a monitoring circuit that generates a pilot activation signal while predefined conditions are met. A primary piloted valve in communication with the monitoring circuit is coupled to the first valve. The first type output port is disconnected from the valve actuator while the pilot activation signal and thus the first valve are deactivated, holding the valve actuator in place.

Abstract: A hydraulic system for aircraft operating devices provides a secondary pressure source for direction and deceleration control in case of loss of pressure from a primary pressure source. The system includes multiple pressure accumulators that include a primary accumulator, which supplies pressurized fluid to a first actuator, and first and second secondary accumulators, which supply pressurized fluid to second and third actuators, respectively. If the primary accumulator is disabled, the first secondary accumulator will supply pressurized fluid to the first actuator. If the first secondary accumulator is disabled, the second secondary accumulator will supply pressurized fluid to the second actuator. By providing multiple, substantially independent accumulators, direction and deceleration control is maintained even in the event of loss of the primary accumulator.

Abstract: A block manifold for a fail safe actuator system allows the actuator operation with a hand pump if electrical power were not available. A method is available to isolate fail safe solenoid valves and an accumulator from a hand pump circuit to relieve the stored energy from the fail safe circuit. An additional set of pilot operated check valves were installed between the motor driven pump circuit and the hand pump circuit. These pilot operated check valves isolated the hand pump circuit from the fail safe dump solenoid and accumulator. These pilot actuated check valves also hold the actuator in the fail safe position as long as the hand pump system was not used. There is also a hydraulic bleed circuit to relieve the accumulator stored energy when the hand pump system was used.

Abstract: A system to lock a roll-suspension arrangement operatively connected to allow pivotal movement of a boom assembly about a fore-and-aft axis independent of a carrier frame is provided. The system includes an actuator cylinder having an end movable in a linear direction relative to a fixed end. The fixed end of the actuator cylinder is connected at the carrier frame, and the movable end is connected at the boom assembly. The system further includes a lock valve located in fluid communication with the actuator cylinder. The lock valve in a closed position prevents a fluid flow therethrough so as to restrain movement of the actuator cylinder and rotation of the boom assembly with respect to the carrier frame. In an open position, the lock valve releases movement of the actuator cylinder so that the boom assembly freely pivots independently of the carrier frame.

Abstract: An electro-hydrostatic actuator unit that contains a sealed pressurized housing filled with a dielectric fluid. A bi-directional motor is immersed in the fluid and drives a gear pump for exchanging fluid via a control circuit between the chambers of a bi-directional hydraulic actuator in response to an input from a controller. The chambers are separated by a piston and a piston rod is connected to an external load such as a plunger type valve. A failsafe circuit is also provided which is arranged to override the control circuit in the event a failsafe condition is detected by the unit controller. The failsafe circuit contains a motor driven pump that provides high pressure fluid from the pressurized reservoir to an accumulator. Valves are arranged to shut down the control circuit and deliver fluid from the accumulator to one of the cylinder chambers to rapidly move the actuator to a desired failsafe position.

Abstract: An hydraulic power assembly 10 is provided, including at least one primary hydraulic power unit 20 supplying hydraulic fluid 30 to a hydraulic system 34, and a contingency hydraulic power unit 50 utilizing the orbiter's helium storage tank 52 to power a contingency hydraulic drive 56 to supply hydraulic fluid 30 from a contingency hydraulic fluid reserve 58 to the hydraulic system 34 during peak loading conditions.

Abstract: The invention relates to a device and method to provide energy for hydraulic systems. The device includes at least one gas generation cartridge (2) and a device (5) for the activation of a gas generation. Gas pressure vessels (2) or pyrotechnic gas generation cartridges (2) can be used advantageously as gas generation cartridges (2). The method of the invention includes activating a gas generation when the pressure in a hydraulic circuit drops.

Abstract: A simple hand held carbon dioxide applicator having a pressurized carbon dioxide cartridge is used to release spring applied hydraulically released brakes. The hydraulic line extending between the hydraulic pump and the brake control valve is provided with a first coupler of a quick coupling with the corresponding second coupler being hydraulically positioned between the hydraulic line and the pump. An auxiliary line is provided having an auxiliary coupler identical to the second coupler so that the auxiliary line can be attached to the first coupler. The auxiliary line is also provided with a gas check valve in the form of a schraeder valve to which the hand held carbon dioxide applicator is pneumatically coupled.

Abstract: A booster 3 has a structure that a return valve 14 is formed into a two-step throttle incorporating a first throttle valve 36 and a second throttle valve 37 formed continuously from the first throttle valve 36. When a valve spool 28 has been moved forwards when the operation is performed, a gap of the first throttle valve 36 is reduced. Also a gap of the second throttle valve 37 is reduced. Therefore, hydraulic fluid discharged from a pump is passed through an inlet passage 12, and then introduced into the second annular groove 13. Then, the hydraulic fluid is throttled by the first throttle valve 36, and then throttled by the second throttle valve 37. That is, the hydraulic fluid is throttled in the two-step throttling manner. As a result of the two-step throttling structure, the overall velocity of the flow of the hydraulic fluid can smoothly be changed without rapid change. Therefore, fluid flow noise caused from the change in the velocity of the flow can be prevented.

Abstract: A fail-safe closure system for one or a plurality of springless process valve actuators is disclosed. An accumulator is provided with an urging means, such as a spring for pressurizing fluid stored therein. A source of pressurized fluid is also provided. Supply pressurized fluid is applied to an opening chamber of one or a plurality of process valve actuators while a flow path is opened to a vent from the closing chamber of the one or more actuators. For closing the actuator or actuators, a flow path is established by which pressurized fluid from the accumulator is applied to the closing chamber of the actuator or actuators while the opening chamber is vented. Control valves are arranged so that if or when they fail, they fail in a position which allows the process valve actuators to close as described.

Abstract: A bi-directional power conversion system interconnects hydraulic and electrical power systems on-board a vehicle such as an air-craft, whereby the power conversion system can selectively convert available electrical power to needed hydraulic power or vice versa. The power conversion system includes a hydraulic machine (15) connected to the hydraulic system (10) of the vehicle, an electrical machine (20) connected to the electrical system (3) of the vehicle through a power converter and control unit (22), a rotational drive shaft (14) mechanically interconnecting the hydraulic machine (15) and the electrical machine (20), and a priority and safety control unit (26) that controls the operation of the system.

Abstract: An electro-hydraulic valve actuator comprising an actuator casing; a piston/rack means in the casing having walls reciprocating linearly to effect linear movements, the reciprocating walls defining a center chamber therebetween and two outside chambers inside the casing; an output shaft in communication with the piston/rack means for driving a valve, the output shaft effecting rotational movements in response to the linear movements of the piston/rack means; resilient return means in each of the two outside chambers engaging the reciprocating walls of the piston/rack means and inner end walls of the casing, the resilient return means biasing the reciprocating walls of the piston/rack means to a closed position; a pumping means; a primary internal flow path for transferring hydraulic fluid from the pumping means to a first output port and into the center chamber, the hydraulic fluid in the center chamber causing the piston/rack means to expand in the casing to transmit the linear movements to the output shaft;

Abstract: A two-stage electrohydraulic pressure control valve modulatably controls engagement of a spring applied, pressure released brake when electrical power directed thereto is suddenly lost. The control valve includes a shutdown valve mechanism between a pilot stage and a main stage to controllably reduce the fluid pressure in an accumulator storage chamber in three distinct stages. The first stage is the immediate blocking of fluid flow from the storage chamber by a flow control valve when fluid passing therethrough in one direction exceeds a predetermined flow rate. The second stage is reducing the fluid pressure in the storage chamber to a predetermined level by a relief valve when the flow control valve is in its flow blocking position. The third stage is accomplished by restricting fluid flow from the storage chamber at a predetermined flow rate through an orifice so that the main stage modulatably controls the reduction of fluid pressure in the brake chamber.

Abstract: A continuously variable hydrostatic transmission includes an input shaft connected to drive a hydraulic pump unit, a grounded hydraulic motor unit, and an output shaft. A wedge-shaped swashplate is pivotally mounted to the output shaft in driving connection to receive output torque resulting from the exchange of pressurized hydraulic fluid between the pump and motor units through specially configured ports in the swashplate. A hydraulically actuated ratio controller is pivotally linked to the swashplate to selectively adjust the swashplate angle relative to the output shaft axis and thereby change transmission ratio.

Abstract: The invention relates to safety device for a cylinder valve automatic switching unit, wherein said valve is automatically closed when some abnormality such as down of an air pressure takes place. A first air-operated selector valve 8 is installed which causes air flowing out of a reservoir tank 10 to flow into a second supply line 3 when air pressure is reduced, whereby a cylinder valve automatic switching unit 1 in the opening situation is caused to make a closing motion for closing a cylinder valve in the opened situation. And, a second air-operated selector valve 9 is further installed which discharges air flowing out of a first supply line 2 to the atmosphere when the air pressure is reduced.

Abstract: A hydraulic brake booster (10) includes a housing (12) which defines a pressure chamber (16) and a piston (18) within the housing (12) is movable in response to pressurized fluid within the pressure chamber (16) to effectuate a brake application. The piston (18) encloses a storage chamber (60) and forms a pair of passages (80, 90) communicating the storage chamber (60) with the pressure chamber (16). A valve member (100) is disposed within the first passage (80) in order to control communication between the storage chamber (60) and pressure chamber (16). The valve member (100) permits pressurized fluid within the pressure chamber (16) to be communicated to the storage chamber (60) in order to charge the storage chamber (60). The valve member (100) also permits high pressure fluid above a predetermined pressure level within the storage chamber (60) to be communicated to the pressure chamber (16).

Abstract: Aviator harness fittings are pneutically actuated by a central device including a pressurized gas cartridge. A firing pin may mechanically pierce the cartridge or automatic ballistic actuation of the firing pin may be accomplished by SEA WARS gas-generating devices when the latter contacts sea water. The ballistic actuation of the present invention requires two separate SEA WAR gas-generating devices to fire simultaneously thereby minimizing the chance of false actuation.

Abstract: A blow-back circuit (10) comprising an accumulator (23) to build up system pressure during normal system operation and an accumulator shut-off valve (13) which prevents dissipation of the accumulator pressure during normal operation. Pressurized fluid is supplied to a fluid motor (11) through a direct drive valve (12). A directional control valve (28) is associated with a switching valve (34) and a stop mechanism (31) which mechanically feedbacks the position of a control surface to be blown back during an emergency. When the control surface is in or blown back to the neutral position, the stop mechanism (31) feeds that data back to the directional control valve (28) so that accumulator pressure will not be further delivered to the fluid motor (11) and a brake (14) will be allowed to prevent further movement of the control surface away from the neutral position. As a result, the control surface is moved to its neutral position with great accuracy and no flutter.

Abstract: The invention relates to the control of a hydraulic jack which can be used, for example, for controlling the orientation of the rear wheels of a vehicle with front guiding wheels. In the event of a failure in the supply of fluid under pressure to the chambers (3, 4) of the jack, these chambers are isolated and the piston (2) is maintained in the position which it occupied when the failure occurred, by means of non-return valves (12). However, when certain conditions are satisfied, for example a sufficiently low speed, the electronic control member (20) activates an auxiliary circuit (30 to 39) in order to return the piston to its middle position and allow driving of the conventional kind with the rear wheels in line.

Abstract: A hydraulic booster equipped with an emergency accumulator, wherein reaction and power pistons are slidably fitted in a housing such that the two pistons define a power chamber therebetween. The booster includes a control valve having a normally closed power chamber passage formed therethrough so as to communicate with the power chamber, and a normally open passage connecting a pump and a reservoir. The valve is operated in response to an operation of the reaction piston, so as to restrict a fluid flow through the normally open passage from the pump toward the reservoir, thereby raising a pressure of the fluid delivered from the pump, and open the power chamber passage to apply the raised pressure to the power chamber. A pressure reducing device is provided in the power chamber passage, for reducing a fluid pressure in the power chamber passage and applying the reduced pressure to the power chamber, at least while a rate of fluid flow through the power chamber passage is higher than a preset limit.

Abstract: A fail-safe electric actuator, for use with a control mechanism such as a valve, is disclosed. The actuator device eliminates the possibility of the control mechanism being locked in operative position by the interruption of electric power, by automatically and mechanically returning the control mechanism to its inopertive position as soon as current is cut off. This is accomplished by the release of a torsion spring, wound previously by the rotation of a fluid-driven vaned torque actuator in turning both the control-mechanism and the electric fail-safe actuator into operative position.

Abstract: An auxilliary hydraulic steering system for use on mobile vehicles having an engine-driven pump supplying hydraulic fluid under pressure to a steering control unit and an accumulator. The accumulator is charged with fluid under pressure from the pump through a charge/discharge valve and connects with the supply line to the steering control unit only when this valve shifts in response to a predetermined pressure in said supply line.

Abstract: A pressure operated control installation, especially for automotive vehicles, which includes a pressure source and a servo member controlled through a control block. The control block includes a logistor, a control element coupled with a control unit, and a bypass line with a throttling arrangement. The pressure conducting inlet of the logistor is connected through the bypass line to a control inlet of the logistor and the control unit controls a connection between the control inlet of the logistor and a return line. At least two control blocks are provided with a control outlet of the logistor of the first control block and a pressure conducting inlet of the logistor of the second control block being connected to the servo member.

Abstract: A fail-safe actuator mechanism has an actuator housing encapsulated within a tank which stores a pressurized fluid media. Ports of the actuator housing are put into selective fluid communication with both the interior and exterior of the encapsulating tank by a valve at selective pressures.

Abstract: Electro-hydraulic control assembly for turbine valves, including electric control means, a shaft connected to a turbine valve, a valve housing and an integrated compact actuator unit disposed in the housing, the actuator unit including an electro-hydraulic converter connected to the electric control means, a hydraulic control cylinder being connected to the electro-hydraulic converter and having a control piston connected to the shaft, and a hydraulic supply system, the supply system including a fluid reservoir, a fluid pump being fed from the fluid reservoir and having a pressure side, an electric motor for driving the pump, and a hydraulic pressure accumulator connected to the pressure side of the pump.

Abstract: An hydraulic supply circuit for a vehicle power steering system of the type having a steering actuator and control valve therefor with hydraulic input, sump and overflow (by-pass) connections and in which any fluid not actually consumed by the actuator is diverted to the overflow connection. A positive displacement pump is provided having an output line connected to the input connection of the steering system. An accumulator having a charging line and a discharging line is used to supply fluid pressure in lieu of the pump. To control flow of fluid to and from the accumulator a charge-discharge valve is provided having charge and discharge modes. In the charge mode the accumulator is charged by the overflow and in the discharge mode pressure fluid is supplied from the accumulator to the input connection for maintaining the steering system in operation while blocking the overflow.

Abstract: The control mechanism is for pneumatic apparatus of the kind comprising a piston-and-cylinder motor coupled between two relatively-movable parts (such as door-leaves) for driving them, when energized, to a predetermined relative position. A pilot valve is actuated when required to switch the apparatus to an emergency mode by isolating the motor from its power source and discharging it into an emergency reservoir having a volume large compared with the maximum volume of gas in the motor. While the pilot valve is actuated, the relatively-movable parts are urged towards their predetermined relative positions by a force small compared with the normal operating force. The pilot valve may be arranged to operate operation of an emergency release bolt, on obstruction detected by a detector valve (in which case a timing reservoir provides time delay before full power is restored), on power failure, or as required.

Abstract: A hydraulic system for a vehicle having an open-center hydraulic brake booster powered by an engine-driven single rotary pump with an unloader valve into which is incorporated a bypass valve to enable a fluid flow to bypass the unloader valve into the brake booster. The invention contemplates the use of the bypass valve for such purpose as pressurizing the fluid circuit upstream of the bypass valve for storaging fluid in a fluid storage member under pressure in case of rest position of the booster for actuating the booster when the pump failed.

Abstract: Implement and steering actuators are selectively actuated through steering and implement control valves respectively by fluid power output of respective steering and implement pumps. A pressure compensator is provided for at times diverting excess fluid from the steering pump to the implement control valve, and the implement pump applies fluid pressure to the implement valve through an unloading valve that gives the charging of an accumulator by the implement pump preference over operation of the implement actuator. The sensing of loss of fluid power in the steering pump activates an emergency control valve to connect the accumulator to the steering valve and to disconnect the pressure compensator from the implement control valve.

Abstract: A gate valve having a top inlet and bottom outlet is provided with a horizontally disposed head slidable between closed and open positions. The valve body includes a seat concentric with an inlet passage and adapted to cooperate with a sealing surface on the head. An annular sleeve is provided within the inlet passage with one end of the sleeve being in contact with the sealing surface on the head. The sleeve and seat cooperate with the valve body and head to define an annular space. A means is provided to pressurize the space immediately prior to contact between the head and the seat. The head is biased to a closed position in the event of power failure. The valve is particularly designed for controlling downward flow of high temperature particulate material under high pressure.

Abstract: A shutoff valve actuator remote control system includes a main control apparatus and a duplicating control apparatus connected therewith. The duplicating control apparatus comprises a self-contained power source in the form of a gas generator with an igniter connected to an emergency remote control line, and further comprises a commutator, a safety valve, and a receiver connected with the gas generator outlet and the commutator. The commutator is also connected with the outlet from the main control apparatus and the shutoff valve actuator.The present invention provides substantially enhanced dependability of control during breakdown conditions and features a simple design.

Abstract: A hydraulically actuated clutch booster utilizes a seat accumulator incorporated in a vehicle seat suspension circuit for a source of fluid pressure when the normal clutch booster fluid supply pump is not operating thereby providing hydraulic assist to operate the vehicle's clutch upon initial start up.

Abstract: A method and apparatus uses energy in an energy output system having a main power source, an energy transmission system and a mechanical output. A first portion of energy generated with the main power source is used to drive the mechanical output under operating conditions. The unused second portion of the energy is diverted to an energy storing means. The second portion of energy is then stored and regenerated on demand. The energy may be used directly to augment the energy requirements in the energy output system during peak periods. In a specific embodiment, a compressed air system is used for storing the energy not used in driving a mechanical output connected to the power source by an energy transmission assembly. The energy transmission in the energy output system is a hydraulic fluid transmission system. A hydraulic fluid diverting mechanism is used to maintain the flow of hydraulic fluid to the mechanical output and to the compressed air energy storage system.

Abstract: A hydraulic fluid power system includes an accumulator which stores a reserve of pressure fluid at pump standby pressure. The charging and discharging of the accumulator is controlled by an emergency steering valve which is operable in response to a predetermined minimum fluid pressure outputted by the steering pump to discharge the stored fluid for emergency steering. The emergency steering valve also has components which serve as a pressure switch which is actuated to complete a circuit through an indicator light whenever the emergency steering valve moves to effect the discharge of the accumulator. The steering valve components are arranged so that premature actuation of the indicator light during pressure drops of short duration are avoided.

Abstract: A hydraulic fluid power steering system includes an accumulator which stores a reserve of pressure fluid at pump standby pressure. The charging and discharging of the accumulator is controlled by an emergency steering valve which is operable in response to a predetermined minimum fluid pressure outputted by the steering pump to discharge the stored fluid for emergency steering. The emergency steering valve also has components which serve as a pressure switch which is actuated to complete a circuit through an indicator light whenever the emergency steering valve moves to effect the discharge of the accumulator.

Abstract: A power brake system has a brake booster operable by differential air pressure provided by a source of vacuum and a source of compressed air pressure. The differential air pressure control valve assembly of the invention maintains a substantially constant available differential of air pressure between the vacuum and compressed air pressures available to the brake booster for booster operation. In the charging mode it directs air pressure from an air pressure pump to an accumulator connected to the pressure inlet side of the booster, charging until the desired pressure differential is attained. In the storage mode, the air pressure from the pump is permitted to flow in its usual manner to another device or circuit utilizing the air pressure. This may be, for example, a part of the vehicle engine emission control system. In the pressure relief mode, the control valve vents excess accumulated pressure to exhaust.

Abstract: PCT No. PCT/US79/00664 Sec. 371 Date Aug. 30, 1979 Sec. 102(e) Date Aug. 30, 1979 PCT Filed Aug. 30, 1979 PCT Pub. No. WO81/00600 PCT Pub. Date Mar. 5, 1981A 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.

Abstract: A hydraulic brake booster is disclosed which includes an integral accumulator to provide a fluid pressure source for emergency failsafe braking. The accumulator includes a bore defined within the booster housing, and a piston slidably mounted in the bore which divides the latter into a pair of fluid compartments between opposite ends of the piston and corresponding ends of the bore. One of the compartments is communicated to the booster inlet port so that the compartment is charged with fluid pressure whenever the pressure level at the inlet port is above some predetermined low value. In one embodiment of the invention, the other compartment is communicated to the fluid pressure reservoir, and a relief valve is carried within the piston which controls flow of fluid between the two compartments.

Abstract: An improved emergency system (10) for a vehicle having a closed center steering valve (12), a pump (14) normally supplying fluid to the valve, and an accumulator (16) for supplying emergency pressurized fluid to the valve when the pump fails. The improvement is a flow directing circuit (18) connecting the accumulator to the valve in parallel relationship to the pump and apparatus for blocking flow from the accumulator to the valve responsive to proper operation of the pump. Adequate emergency steering is provided to a closed center steering valve system by the above arrangement.

Abstract: A hydraulic brake booster includes a housing which substantially defines a pressure chamber and the housing slidably supports a control valve for communicating pressurized fluid to the pressure chamber. A piston is movably disposed within the housing to move in response to pressurized fluid within the pressure chamber and the piston substantially defines a storage chamber located inside the piston. A charging valve communicates pressurized fluid to the storage chamber and a relief valve vents the storage chamber to the pressure chamber when the pressure stored in the storage chamber is above a predetermined value. An input member cooperates with the piston to define an actuating cavity which communicates with the relief valve so that the input member is movable relative to the piston to pressurize the actuating cavity which causes the relief valve to open communication between the storage chamber and the pressure chamber.

Abstract: A hydraulic brake booster is disclosed which includes an integral accumulator to provide fluid pressure source for emergency failsafe braking. The accumulator includes a bore defined within the booster housing, and a piston slidably mounted in the bore which divides the latter into a pair of fluid compartments between opposite ends of the piston and corresponding ends of the bore. One of the compartments is communicated to the booster inlet port so that the compartment is charged with fluid pressure whenever the pressure level at the inlet port is above some predetermined low value. In one embodiment of the invention, the other compartment is communicated to the fluid pressure reservoir, and a relief valve is carried within the piston which controls flow of fluid between the two compartments.

Abstract: In the case of pump failure a spool valve instantly connects a pressurized fluid accumulator with the servo motor which assistingly activates the master cylinder and isolates a power steering mechanism fluidly connected to the servo motor so that only the power brake is temporarily operable but with stepwise decreasing effectiveness.

Abstract: An electric control circuit for use in the ignition system of a vehicle having a vehicle battery powered auxiliary steering system which is energized upon engine failure or shutdown during vehicle operation. The ignition circuit disconnects the auxiliary steering system from the vehicle battery during heating of the pre-start intake air and during starting of the engine to eliminate unnecessary drain on the vehicle battery.

Abstract: A negative energy power supply which operates submerged equipment like a hydraulic actuator. A main component of the system is a submerged chamber held at substantially atmospheric pressure. It is connected to submerged equipment having intake and discharge ports controllable by remotely operated valves. When the intake port is opened to water at the submerged depth of the equipment and the discharge port is vented to the chamber, the resulting pressure difference operates the submerged equipment. The system can also have appropriately connected to it, a pressure amplifier to increase the water pressure at a submerged location and a pump to purge the chamber.

Abstract: A fluid power device such for example as one for opening and closing clam shell gates is operated by a ram under fluid pressure. A tank is provided for storing fluid under pressure and by a system of valving extension of the ram, as for a gate opening operation is inhibited until enough fluid under pressure is stored in the tank to assure completion of reverse operation of the ram to close the gates.