Abstract: A valve (10) including a first port (12), a second port (14), a third port (16) and a flexure (30), the flexure (30) being moveable between a first position which causes the first port (12) to open, a second position which causes the second port (14) to open, and a third position which causes the first and second ports (12, 14) to close, wherein at least a part of the flexure (30) is magnetisable, to provide a first magnet (32), a second magnet (34) is associated with the first port (12) and a third magnet (36) is associated with the second port (14). A valve assembly includes a pair of valves wherein only one of the valves is operable at any given time.

Abstract: The present disclosure relates to an energy reclaiming system for an electric forklift truck. The energy reclaiming system includes an electronic device operated by a motor when a working machine is raised and operated by a generator when the working machine is lowered, a hydraulic pump/motor connected to the electronic device and configured to perform two functions of a hydraulic pump and a hydraulic motor, a main control valve unit including a lift cylinder operating unit connected to the hydraulic pump/motor and configured to operate a lift cylinder and a secondary consumer operating unit connected to the hydraulic pump/motor and configured to operate a secondary consumer, and a control lever including a control valve configured to control the lift cylinder or the secondary consumer through the lift cylinder operating unit and the secondary consumer operating unit of the main control valve unit, respectively.

Abstract: A hydraulic valve assembly for selectably delivering hydraulic fluid from a supply of hydraulic fluid to one of a first hydraulic operator and a second hydraulic operator is disclosed. The assembly includes first and second supply ports which communicate with the supply and four operator ports. First and third ports communicate with the first hydraulic operator. Second and fourth ports communicate with the fourth hydraulic operator. First and second chambers are provided. The first chamber communicates with the first supply port and first and second operator ports. The second chamber communicates with the second supply port and third and fourth operator ports. Two selection valves operating in unison are each located in each chamber. The selection valves operate between a first position at a first hydraulic fluid pressure and a second position at a second hydraulic fluid pressure.

Abstract: A safety circuit for protecting against an inadvertent operation activation of a pneumatic drive of an automatic assembling machine has at least one vertical cylinder (1) and one horizontal cylinder (2), each being controlled by one of first and second multi-way valves (3, 4) and fed by a primary pneumatic circuit. Two further pneumatic control circuits (8,9) are included in the automatic assembling machine that are automatically switch into and out of the primary pneumatic circuit, wherein the at least one vertical cylinder (1) and the at least one horizontal cylinder (2), after the “switching into”, either remains in its current position or moves to a rest position. Opened and closed switching of a pneumatic primary circuit is caused according to an activated mode-of-operation set by a system control (SPS) of the automatic assembling machine.

Abstract: In a boiling water reactor controlling each control rod hydraulically by driving a solenoid valve, the control system comprises an operation control means 41 having a duplicated data processing unit for generating sequence patterns based on the timing of the driving sequence based on the control information provided manually, a transmission control means 42 for creating a command word corresponding to each control rod being controlled based on said sequence pattern, and mutually communicating each command word between duplicated data processing units and computing the AND logic of said data within a predetermined time difference, and when the computed result coincide, transmitting the selected command word serially; a transmission unit 32 for receiving said command word and performing protocol conversion thereto, and transmitting the same to a plurality of transmission branch units positioned downstream as the control command; and a solenoid valve drive circuit 31 for driving the control rod drive unit corres

Abstract: In the construction machinery equipped with an engine, a hydraulic control unit and a machine controller, there is provided an antitheft device for the construction machinery, which can prevent the engine from starting and the hydraulic control unit from working with reliability no matter how the starter circuit of the engine is modified. The initial state of the machine controller is so set that the fuel injection by a fuel injection unit of the engine is halted and that the operations of control units in the hydraulic control unit are halted, and an antitheft control unit is provided to release the initial state of the machine controller upon receiving a release signal from the antitheft control unit.

Abstract: A hydraulic switching device for use in a circuit comprises at least two movable drive units producing movement in a functional direction or a counter-direction. The drive units can be pressurized with a pressure medium via at least two connection lines. Externally controllable selector switches are provided for controlling the pressurization so that exactly one controllable selector switch is provided for each drive unit and at least two drive units are interconnected via logical AND and/or OR valve elements so that at least with introduction of force to the first drive unit in the functional direction, a force release of the second drive unit is possible, and with an introduction of force to the first drive unit in the counter-direction, an introduction of force to the second drive unit in the functional direction, in the counter-direction or a force release is made possible.

Abstract: This electrohydraulic actuator comprises a pair of hydraulic rams (12, 13) and a rocker (14) integral in terms of rotation with an input shaft (7) of the barrel, the rams are arranged parallel with one another in such a way as to be able to control the rotation of the rocker to make it adopt predetermined angular positions corresponding to the gears (R, N, 1, 2, . . . ) selected and this actuator also comprises solenoid valves for controlling the rams. The rocker (14) extends transversely to the shaft (7) and its ends are designed to be able to interact with respective pistons (17, 18) of the rams (12, 13), each ram comprises three pistons (24, 25, 17; 26, 27, 18) which are coaxial and have different cross sections, arranged in chambers (28, 29) of corresponding cross sections formed in the body (11). This electrohydraulic actuator permits extremely quick and easy control of gear selection for a structure which is relatively simple and has a modest cost of manufacture.

Abstract: A control logic for a multiple use hydraulic system includes a selector switch having a first position connecting a battery to a treadle switch operable to energize a solenoid pilot valve for communicating pilot fluid to an end of a first directional control valve. The selector switch has another position connecting the battery to a bi-directional push button switch operable to selectively energize a pair of solenoids of a second pilot valve. Energizing one of the solenoids moves the second pilot valve in one direction to communicate pilot fluid to an end of the first and a second control valve. Energizing the other solenoid moves the second pilot valve in the opposite direction to communicate pilot fluid to the other end of the control valves. The selector switch has a third position connecting the battery to a pair of pressure switches connected to a pair of lines connecting a manually actuated pilot valve to a pair of solenoid blocker valves.

Abstract: In certain machines, such as construction equipment, it is desirable to provide a supplemental fluid supply for hydraulic steering systems to maintain sufficient fluid flow should a failure occur in the primary fluid supply. It is also desirable to provide retarding or dynamic braking to help control speed of the machine when operating downhill with a heavy load. A ground driven pump is provided to supply fluid to a selector valve for selectively directing the output of the ground driven pump to a steering system or a dynamic braking system. The selector valve is responsive to pressure in the steering system to direct flow from the ground driven pump to the steering system when the pressure drops below a predetermined level. The operator may selectively direct flow from the ground driven pump to the dynamic braking system when dynamic braking is needed.

Abstract: This is an electro-pneumatic control device which includes a valve station (2) designed similar to a subassembly. The valve station (2) is provided with a fluid conductor (4) which is equipped with a plurality of valves (12) and a central electronic control unit which is formed by a control block (19). The control block (19) is a direct component of the valve station (2),so that a external central control unit is eliminated.

Abstract: A device for controlling hydraulic steering clutches and brakes in a crawler vehicle such as a bulldozer has a simple structure so as to be manipulated by a monolever. The device comprises a single steering lever (5), four proportional pressure control valves (1), (2), (3), (4), left and right steering clutch pistons (7), (7a) and left and right brake cylinders (8), (8a). The four valves are composed of two sets of valves, one set of two valves for steering clutches, in which the timing of the rise of hydraulic pressure is earlier, and one set of two valves for brakes, in which the timing of the rise of hydraulic pressure is later than the former.

Abstract: A drive system for a lid or a flap of a convertible car body in which the control effort for the drive system is reduced by configuring the working cylinder as a control valve which releases the lid or the like after unlocking of the lock for lifting by the lifting cylinder, and is connected between the control device and the lifting cylinder.

Abstract: A control change system for a backhoe in a construction vehicle, comprising a plurality of pilot valves for generating a pilot pressure corresponding to operations of a first and a second control levers, respectively, and a hydraulic switching unit for relaying the pilot pressure from the pilot valves and supplying the pilot pressure to a plurality of control valves. This switching unit includes a plurality of slidable spools for supplying the pilot pressure from the pilot valves selectively to the control valves. The control system further includes a first and a second switching members for selectively sliding the plurality of slidable spools. The first switching member is operable to select the swing cylinder or the hydraulic motor to be controlled by a shift in one direction of the first control lever. The second switching member is operable to switch interlocks between the first and second control levers and a boom cylinder and an arm cylinder.

Abstract: A control change system for a hydraulic working vehicle having a plurality of hydraulic actuators operable by control levers each shiftable to a plurality of control positions. This system includes a plurality of pilot-operated control valves for controlling pressure oil supply to the hydraulic actuators, respectively, pilot pressure generating valves for generating a pilot pressure in accordance with the control positions of the control levers, and a pilot pressure switching unit for receiving the pilot pressure from the pilot pressure generating valves and outputting the pilot pressure selectively to the control valves. The pilot pressure switching unit includes a plurality of spools slidable to change communicating passages between a pilot pressure input section and a pilot pressure output section of the switching unit.

Abstract: In the double brake-booster and master cylinder assembly, the booster comprises, in an outer casing 10, a fixed partition 11 defining, inside the casing 10, a front space A and a rear space B, each space A, B being divided in a sealed manner into a front chamber 12, 18 and a rear chamber 14, 20 by a movable partition 16, 22, at least one elastic mechanism 31 tending to displace one 16 of the movable partitions 16, 22 rearward, at least one passage 38 connecting the two front chambers 12, 18, at least one passage 53 connecting the two rear chambers 14, 20, a pressure difference being established between the front 18 and rear 20 chambers of the rear space B by a valve mechanism 35 on actuation of a control rod 27 in order to actuate an output rod, the output rod actuating a piston of the master cylinder.

Abstract: A multiplexed hydraulic control system which avoids the use of a rotary multiplexer and thereby allows for random selection of the multiplexed outlet ports and variable dwell times for the respective ports. A single hydraulic input is multiplexed among a plurality of hydraulic outputs. A control system provides two types of signals: (1) modulation signals selected from a plurality of multiplexed input signals for producing a modulating hydraulic flow, and (2) selector signals for operating on the multiplexer means to route the modulated signal to the appropriately selected channel.

Abstract: A multiplexed hydraulic control system having a plurality of hydraulic channels for individually controlling the positions of a plurality of actuators in the respective channels in accordance with a corresponding plurality of electrical control signals. The system includes a relatively small multiplexing valve or valve array which has a common input and a plurality of individually selected outputs. The multiplexing valve has a control input which is responsive to a source of binary selector signals, such selector signals being used to directly address any particular channel connected to the multiplexer. The system also includes means for modulating a hydraulic signal in accordance with selected ones of the plurality of electrical control signals, and applying the modulated hydraulic signal to the multiplexer common input.

Abstract: A multiplexed hydraulic control system having a plurality of channels and a common source of modulated hydraulic fluid. The common source is shared among the plurality of channels by providing a plurality of selector valves, one for each channel, with electrical solenoids for the selector valves being individually controlled by a control means. In a normal operating mode, the selector valves are operated individually and the modulating means is controlled to direct fluid to the selected channel in accordance with the demands placed on movement of the actuator in that channel. In a second slewing mode, multiple selector valves are energized at the same time and the modulator is controlled to produce sufficient fluid flow to slew all of the actuators in the selected channels at a desired rate.

Abstract: A vacuum brake power booster for a slip-controlled hydraulic brake unit in which a major reduction of the costs of manufacture and of mounting and simultaneously an increase of its reliability in operation is provided. A first movable wall (7) within the booster housing is movable independently of the brake pedal input member (11) and a second movable wall (15) is provided at the first control housing part (52).

Abstract: A fluid powered actuator system includes two identical fluid powered actuators operable by respective supply pressures which are controlled by respective identical valve arrangements. Operating positions of flow control elements of the valve arrangements are applied through respective couplings to a differential arrangement which operates, if these positions differ by an unacceptable amount, to apply an error indication through respective coupling to prevent the supply pressures from being applied to the respective actuators.

Abstract: An automatic, hydraulically actuated, sequencing valve for use with a pair of hydraulic acutators (e.g. double acting hydraulic cylinders) includes a valve body having a cylindrical bore therein. Cam members at either end of the bore are engaged by pins on the ends of a cylindrical spool, thereby rotating the spool 30.degree. each time it engages one of the cam members. A third cam member incorporated into the spool alternately locks open one of a pair of check valves as said spool is pressure shifted between the two bore cam members. The third cam member operates a locking system which permits only one of the two hydraulic cylinders to operate at a time and in sequence.

Abstract: The thread winding machine includes a piston and cylinder unit, comprising a cylinder housing with first and second chambers and a dividing structure between said first and second chambers. A piston is movable longitudinally in the first chamber and a piston extension projects from said piston towards the second chamber. A port in the dividing structure receives the piston extension when the piston is near the dividing structure, thereby separating said first and second chambers. A thread guide is connected to the piston of the piston and cylinder unit for movement in combination therewith.

Abstract: An electrohydraulic actuator system has a first pair of actuators and a control circuit and a control valve for each actuator. The control circuits generate actuator position error signals and are also responsive to divergence of the operating position of the respective valves from a mean valve operating position thereby tending to maintain the valve operating positions, and hence the forces on the actuators, identical. The magnitudes of the position error signals are limited to limit overdrive of the valves in the event of minor malfunctions thereof and to permit a malfunction indication to be provided. The system also includes a further pair of actuators having an associated control circuit which is responsive to a selected differential position of the further actuators, for causing one of these actuators to be driven away from a limiting position of the other actuator until the required position differential is obtained.

Abstract: There is described a furrow opener apparatus capable of operating in a furrowing mode and a carrying mode. The apparatus consists of a double acting hydraulic cylinder having one end connected to a furrow opener drag arm and the other end connectable to a drill rig. It incorporates a pressure cushioning system consisting of at least one pressure absorber and hydraulic lines communicating through a mode valve with both the thrust and draw sides of the double acting cylinder. It further communicates through a single or double acting hydraulic valve to the hydraulic pump and reservoir of an associated prime mover such as a tractor. The mode valve is hydraulically connected to both the thrust and draw sides of the double acting cylinder. In a first mode the mode valve is hydraulically connectable to the pressure cushioning system and in a second mode hydraulically connected through a double acting hydraulic valve to the hydraulic pump and hydraulic reservoir of the prime mover.

Abstract: A pushbutton control system for raising and lowering the dump body of a dump vehicle. Included are "up", "hold" and "down/float" switches which are connected in circuit with "up", "down" and "float" solenoid valves. These valves on energization direct pressurized air into the "up", "down" and "float" chambers of two air cylinders included in an actuating mechanism for a hoist valve controlling the telescopic hoist cylinders of the vehicle. The dump body is raised upon depression of the "up" switch with the consequent opening of the "up" valve. The depression of the "down/float" switch, resulting in the opening of the "down" valve, causes the dump body to lower by the forced contraction of the hoist cylinders. Upon subsequent release of the "down/float" switch the "float" valve opens to allow the dump body to lower under its own weight. The depression of the "hold" switch, with the consequent closure of all the solenoid valves, makes it possible to hold the dump body against movement in any desired position.

Abstract: Container handlers comprise a plurality of double-acting hydraulic cylinders to effect the various side shift, twist lock, tilt, height adjustment, and spread modes of operation. Separate control valves and hoses, entrained over the mast assembly having the attachment thereon, are required to effect such functions selectively. This invention is directed to a programmed electro-hydraulic control circuit when reduces the required number of hoses to two and provides a non-complex system which can be operated expeditiously.

Abstract: A hydraulically driven utility vehicle comprising hydraulically operated, reversible propulsion means on each side of said vehicle, a source of hydraulic fluid contained on said vehicle, a first hydraulic flow control valve coupled between said hydraulic source and said propulsion means on one side of said vehicle, a second hydraulic flow control valve coupled between said hydraulic source and said propulsion means on the other side of said vehicle, and a control stick hydraulically coupled to said first and second flow control valves for controlling vehicle speed and direction by selectively positioning said first and second control valves whereby movement of said stick causes said flow control valves to direct hydraulic fluid from said source to said propulsion means to control speed and steering of said vehicle.

Abstract: A three-circuit fluid system has at least one work element served by a pressurized fluid source and a plurality of work elements connected in interruptible series in each of the second and third circuits. A control system is provided for selectively diverting excess fluid from the pressurized fluid source of the first circuit to the second and third circuits in one mode of the control system and diverting excess fluid from the pressurized fluid source of the first circuit to only preselected work elements of the second and third circuits in a preselected order in another mode of the control system.

Abstract: More specifically, the invention includes a single lever control mechanism for controlling the operation of hydraulic cylinders and including a control housing, a manually operable lever, and a support member housed in the control housing and having a supporting surface. The single lever control mechanism also includes a pivot member rigidly connected to the lower end of the lever and supported on the supporting surface of the support member for rocking movement from a neutral position in a first pivotal direction and in a second pivotal direction transverse to the first direction. The control mechanism also includes a first cable attached to one side of the pivot member and being adapted to be operably connected to a first hydraulic cylinder for actuating that hydraulic cylinder in response to pivotal movement of the lever and the pivot member in the first direction.

Abstract: A control mechanism for controlling a reversible pump that selectively supplies fluid to two different motors forming separate functions includes a control lever pivoted about a fixed axis and having said pump connected thereto. A control console is located adjacent the control lever and cooperates therewith to define a plurality of distinct operating positions on opposite sides of a neutral position for said control lever. The control lever and control console also have releasable interlock means defining the neutral position for the control lever and the pump.

Abstract: A contact free device for limiting the relative movement of hydraulically actuated members in which the device includes a proximity switch actuated at each limit position of the members and which interrupts the supply of hydraulic actuating fluid to the members. The supply of fluid to the members is resumed when movement of the members relatively away from the respective limit position is initiated.

Abstract: A vehicle includes first and second drive transmission assemblies, each having a control element and associated control valve for selectively establishing forward and reverse operation thereof. A control system therefore includes a plurality of master and slave cylinders for individually moving the control elements, a first manual control for operating the transmission assemblies at substantially the same speed and direction, and a second manual control for controllably altering or overriding the first manual control for steering purposes.

Abstract: A pilot-operated valve structure for controlling high pressure fluid flow relative to a pair of cylinders, each having an extend port and a retract port. The valve structure has a pair of pilot-operated 3-way valves, each with a poppet valve member and with pilot valve structure including pilot lines directed to the 3-way valves and to the retract ports of the cylinders. The pilot valve has multiple positions including a neutral position whereby pilot pressure may be directed to the 3-way valves for positioning thereof and to the retract ports of the cylinder for holding the pistons in the cylinders retracted or causing retraction of a piston of an extended cylinder. Two alternate positions of the pilot valve cause positioning of one or the other of the 3-way valves to cause extension of the piston in the associated cylinder while the piston in the other cylinder is maintained in retracted position.

Abstract: Control apparatus is provided for a mechanism which has first, second and third work elements each movable between a first position at which the work element is fully retracted and a second position at which the work element is fully extended. The control apparatus includes a single lever device for controllably moving one of the work elements between the first and second positions while maintaining the other work elements in preselected positions in response to controllably directing a pressurized fluid.

Abstract: Each consumer is provided with a load-compensated direction-reversing valve. Each valve performs a throttling function and a pressure-compensation function in order to establish a selected volumetric flow rate, and also a direction-control function. Each valve comprises a first control valve stage and a second control valve stage. One stage performs the throttling function, the other the pressure-compensation function. One of the two control valve stages also performs the direction-control function. The pressure drop across the stage which performs the throttling function at least in part controls the setting of the stage which performs the pressure-compensation function. Each valve is provided with an electromechanical transducer generating electrical signals indicative of the settings of the stage which performs the pressure-compensation function.