Abstract: There are provided a position calculator that determines a position of working equipment included in a work machine, a display that displays a route image corresponding to a route through which the working equipment moves, and a display processor that causes, on the basis of a position of the route and a position of the working equipment determined by the position calculator, the display to display the route image corresponding to a portion of the route that is shielded by the working equipment with a predetermined position serving as a viewpoint in a form different from the route image corresponding to a portion of the route that is not shielded by the working equipment.

Abstract: A hydraulic excavator drive system (1) includes an arm control valve (31) and an arm switching valve (41). The arm switching valve (41) is connected to an arm pushing supply line (34) by a rod-side line (42) and to an arm crowding supply line (35) by a head-side line (43). The arm switching valve (41) is switched between a neutral position, a recycling position in which the arm switching valve (41) allows the rod-side line (42) to communicate with the head-side line (43) and a second tank line (44), and a meter-out control position in which the arm switching valve (41) allows the head-side line (43) to communicate with the tank line (44). The arm switching valve (41) incorporates therein a check valve (45) that allows a flow from the rod-side line (42) toward the head-side line (43) when the arm switching valve (41) is in the recycling position.

Abstract: An operator display system for a material handling vehicle, the material handing vehicle having a material handling device comprising an arm and a material handling implement mounted on the arm, the operator display system being operable to receive input information comprising information relating to the orientation of the arm and of the material handling implement and calculate the position of the material handling implement, the operator display system further having a head-up display, the operator display system being operable to generate an output in accordance with the input information and display the output on the head-up display.

Abstract: A valve stack for a work machine is disclosed. The valve stack has first and second valve bodies, each with first and second mounting surfaces and first and second valve members. The valve stack further has a third valve body with a mounting surface configured to engage the second mounting surfaces of the first and second valve bodies, and at least one valve member disposed within the third valve body. The at least one valve member is movable between a first position at which movement of a first operator control device corresponds to movement of the first valve member and movement of a second operator control device corresponds to movement of the second valve member, and a second position at which movement of the first operator control device corresponds to movement of the second valve member and movement of the second operator control device corresponds to movement of the first valve member.

Abstract: A vehicle lift control maintains multiple points of a lift system within the same horizontal plane during vertical movement of the lift engagement structure by synchronizing the movement thereof. A vertical trajectory is compared to actual positions to generate a raise signal. A position synchronization circuit synchronizes the vertical actuation of the moveable lift components by determining a proportional-integral error signal.

Abstract: It is designed that an oil pressure signal can be output by operating an operation lever in a twisting direction; a structure can be made simple and its assembly and adjustment are easy; an operation force can be reduced; and a layout is not restricted. It is also designed that when the operation lever is left free after it is twisted, it returns smoothly to the original neutral position. When the operation lever is twisted about the lever axis, the shaft supported by bearings is twisted. The twist of the shaft is converted into the movement in a direction to move the pistons by first and second levers, and the pistons are moved. When the pistons are moved, the oil pressure signal is output from the discharge ports. A disk plate is separated into a first disk plate to which the root of the operation lever is attached and a second disk plate which is tiltably supported by a tilting fulcrum.

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: Hydraulic device for directional control of a vehicle using a single lever. The device includes a hydraulic manipulator (1) with four outlets, forward/reverse and right/left. A selection device (4) with four selectors (5) in a bridge is connected to the manipulator, and the outputs are connected to four motors for reverse-left, forward-left and reverse-right and forward-right control of the running components of the vehicle. A slide valve (7) with two positions, respectively one with direct connections and one with crossed connections, is inserted into the two feed lines of the motors (6 AVG, 6 AVD or respectively 6 ARG, 6 ARD). A control input (10) of the slide valve is connected to the FORWARD and REVERSE outputs of the manipulator, by virtue of which the control of the vehicle remains fully ergonomic, including for a rotation of the vehicle about a central vertical axis.

Abstract: A control and safety system for coordinating movement of multiple hydraulic cylinders to reciprocally rotate a truck-mounted refuse compacting arm. The system includes a logic board controller in communication with a cam and switch arrangement mechanically linked to the rotating arm. Signals from the switches indicate the position of the arm to the logic board which responds by operating directional control valves to regulate movement of the cylinders. A pressure switch is activated to rotate the arm in the opposite direction if the arm is prevented from reaching a limit switch.

Abstract: In a working vehicle including a first control valve assembly (15) for controlling the operation of a hydraulic lift cylinder (14), a cylinder case (13) of the lift cylinder includes, at one of its side surfaces, a vertical seating surface (52) on which a second control valve assembly (20) for controlling the operation of plural another hydraulic actuators (18, 19) is mounted. The second valve assembly includes plural control valve spools (31, 32) which extend in the valve case axially of the vehicle at levels different from one another.

Abstract: The present invention includes a single joystick for the simultaneous control of three spool valves for use on a construction machine. A first portion of the joystick is moved in a first direction which causes a cam to selectively depress a first pair of plungers to control the first spool valve. Movement of the first portion in the second direction causes the cam to selectively depress a second pair of plungers thereby controlling the movement of the second spool valve. A handle of a second portion of the joystick rotates about an axis causing a plate to rotate in a corresponding manner. The corresponding rotation of the plate causes a link member to rotate about the axis causing a pair of lugs to selectively depress a third pair of plungers to control the third spool valve. The mechanism for depressing the third plungers works independently of the position of the first portion so that the control of the third spool valve is independent of the control of the first and second spool valves.

Abstract: This invention provides a three-function control mechanism that employs a single control lever for controlling a first, a second and a third actuator and which may be used in connection with a bulldozer. A torque-amplifying device is provided for assisting in the activation of at least one of the actuators. The control mechanism includes a control bracket, a control handle, and first, second, and third bellcranks pivotably supported by the control bracket. The control mechanism further includes first, second, and third linkage that interconnect the control lever, through the bellcranks, to respective ones of the first, second, and third actuators. The torque-amplifying device is coupled to at least one of the bellcranks in order to assist in the pivoting of the bellcrank. Due to the supporting an arrangement of the control lever, bellcranks, and linkage, the control lever may be moved forward or backward, twisted clockwise or connterclockwise, or moved side to side either separately or in unison.

Abstract: This invention provides a three-function control mechanism that employs a single control lever for controlling a first, a second and a third actuator and which may be used in connection with a bulldozer. The control mechanism includes a control bracket, a control lever, and first, second, third, and fourth bellcranks supported by the control bracket. The control mechanism further includes first, second, and third linkage that interconnect the control lever, through the bellcranks, to respective ones of the first, second, and third actuators. Due to the supporting arrangement of the control lever, bellcranks, and linkage, the control lever may be moved forward or backward, twisted clockwise or counterclockwise, or moved side to side either separately or in unison. In doing so the control lever thereby respectively actuates the first, second, and third actuators.

Abstract: A reliable pilot valve assembly having a control lever is produced at low cost while installed without requiring any additional switch and wiring and piping work. The assembly has a main valve body (1). A spool (27) is slidably mounted in the body (1) so as to be movable between a first and a second position. The spool (27) permits the pressure oil to circulate in a forward direction through a pair of the outlet ports and a pair of main outlet ports of the assembly when the spool (1) stays in the first position, and permits the pressure oil to circulate in a reverse direction (opposite to the forward one) through the pair of the outlet ports and the pair of the main outlet ports when the spool (1) stays in the second position, the main outlet ports being connected with a hydraulic circuit.

Abstract: A work vehicle (2) having an implement position controller (50). Set elevations and orientations of the work implement (5) can be preselected and changed. The controller (50) automatically positions the implement (5) in the desired elevation and orientation. Means (51) for preventing the work implement (5) from falling into the ground are also provided.

Abstract: An operating apparatus for a hydraulic shovel for operating a plurality of control valves which control the operation of work devices includes pilot type control valves, pilot valves, levers for operating pilot valves, and an operating pattern switching valve. The operating pattern switching valve has a rotary spool inserted into a casing. A plurality of input ports are provided in a peripheral surface of the casing with phases deviated from each other axially and peripherally. A plurality of output ports are provided oppositely to the input ports.

Abstract: A hydraulic circuit for a construction machine which operates an actuator for working machine simultaneously with an actuator for working element without degrading the operation of the actuator for working machine. The hydraulic circuit comprises a first hydraulic pump, a first directional control valve connected to the first hydraulic pump and controlling an operation of the working machine actuator, a third directional control valve controlling an operation of the working element actuator, a second directional control valve connected to a second hydraulic pump, a first pilot operating device for controlling an operation of the first directional control valve and a second pilot operating device for controlling an operation of the third directional control valve.

Abstract: A hydraulic control valve is disclosed which is adapted to independently control the flow of hydraulic fluid to several consumer lines. The control valve includes a housing having a central bore, a pair of axially spaced apart consumer lines comunicating with the bore, a tank line communicating with the bore and positioned between the consumer lines, and a pair of hydraulic inlet lines communicating with the bore on the outer side of respective ones of the cosumer lines. A pair of slide valves are positioned in the bore, and each slide valve is supported in a neutral position by a coil spring. The two slide valves may be independently moved from their neutral position by a hydraulic control system, so that each slide valve is adapted to selectively establish communication between one of the consumer lines and the tank line, and between such consumer line and one of the hydraulic inlet lines.

Abstract: In a selective control device for plural kinds of oil-hydraulic actuators comprising an actuator selective valve for selecting an operative oil-hydraulic actuator from among plural kinds of oil-hydraulic actuators and a directional control valve for operating the selected actuator extendedly and retractedly, the actuator selective valve is provided with a quick extensional position which functions to connect an extensional pressure port thereof to a bottom side oil chamber of the selected actuator and also to connect a head side oil chamber to the bottom side oil chamber in order to extend the selected actuator quickly. The construction of the actuator selective valve eliminates a quick extensional valve adopted in a prior oil-hydraulic control device.

Abstract: An elevating apparatus for a working vehicle includes separate front lifting and rear lifting mechanisms that can be elevated by hydraulic cylinders, a feedback rod arranged between a link arm of one of the lifting mechanisms and a hydraulic pressure control apparatus for controlling the hydraulic cylinders. A change-over lever selects the front lifting mechanism or the rear lifting mechanism, and an elevating lever controls elevation of the lifting mechanisms. When one of the lifting mechanisms is selected and elevated by operation of the change-over lever, the elevating lever is operated normally without causing abutment between an adjuster member attached to the feedback rod that is interactive with the elevating lever, and an interactive member of the elevating lever. A return mechanism between the change-over lever and the elevating lever enables the elevating lever to be returned to the neutral position when selecting one of the front and rear lifting mechanisms.

Abstract: An electro-hydraulic control system includes a plurality of two-position control valves, each controlling fluid flow into and out of a corresponding one of a plurality of hydraulic functions. First and second pressure responsive servo actuators associated with each control valve operate to move each control valve to first and second positions, respectively. A two-position, solenoid-operated, pilot valve controls fluid flow into and out of a pilot circuit. The pilot circuit communicates fluid to and from the second servo actuator of each control valve and to and from a plurality of two-position, soleniod-operated, pilot valves. Each pilot valve controls fluid flow into and out of the first servo actuator of a corresponding one of the control valves. A detent mechanism holds each control valve in either its first or its second position in the absence of fluid pressure in the servo actuators.

Abstract: An equalizer is arranged to continuously sense the control pressures of two valves. In the event of a differential between the control pressures, the equalizer operates to selectively adjust one valve so that the control pressures of both valves will thereafter be substantially equal.

Abstract: A control actuation system for an aircraft including an electromechanically controlled, hydraulically powered actuator for driving a main control valve of a dual hydraulic servo-actuator control system. The actuator includes a tandem piston connected to the main control valve which is controllably positioned by a staged valve of relatively short stroke whereby a force motor of minimum size and energy requirements may be used to directly drive the valve. The staged valve includes a linearly movable valve plunger for simultaneously controlling the differential application of fluid pressure from respective hydraulic systems on opposed pressure surfaces of respective piston sections to cause movement of the piston in response to relatively short axial movement of the valve plunger as long as at least one hydraulic system remains operative.

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: An electric hydraulic control device for controlling hydraulic cylinders of work tools in a construction vehicle, in which control valves of the hydraulic cylinders are controlled in two ways. For some work tools which need not be controlled smoothly and finely, the corresponding control valves are controlled directly by an electric signal outputted according to the position of the operation levers, and for other work tools which must be controlled smoothly and finely, the corresponding control valves are controlled through an electric servo mechanism which is operated by an electric signal representative of the amount by which the operation lever is manipulated. In addition, there is provided a detector for detecting as to whether the transmission lever is in the locked condition, and electric systems of all of the control valves are rendered inoperative when the transmission lever is in the locked condition.

Abstract: A hydraulic system for synchronizing telescoping sections of a crane boom comprising a fixed section and second, third and fourth sections that can be extended and retracted, hydraulic cylinders between the sections for extending and retracting the adjacent sections relative to one another and a control valve for each cylinder. Cables are provided between the sections such that a non-uniformity in movement of the sections causes a change in displacement of the cables which is sensed by position sensing devices to provide a hydraulic pilot signal for modifying flow of hydraulic fluid to the cylinders.

Abstract: A redundant control actuation system for an aircraft including an electro-mechanically controlled, hydraulically powered actuator for driving a main control valve of a servo-actuator control system. The actuator includes a tandem piston connected to the main control valve and a force motor driven tandem pilot valve axially movable in the piston for simultaneously controlling the differential application of fluid pressure from respective hydraulic systems on opposed pressure surfaces of respective piston sections to cause movement of the piston in response to relative axial movement of the pilot valve as long as at least one hydraulic system remains operative. The piston pressure surfaces are sized and arranged to minimize force unbalance on the piston due to pressure variations in the hydraulic systems. Also, a pilot valve centering spring device may be provided to minimize undesirable transient motions during system turn on and shut down.

Abstract: A single lever pilot control system (10) controls the simultaneous operation of two actuators (16,18). A mechanism (48) holds a first control valve (20) in an actuated position in response to movement of the handle (29) along a first axis (44) while freeing the handle (29) to return to a neutral position. Further movement of the handle (29) along a different axis to operate the second actuator (18) does not override the automatic stopping of the first actuator (16). The mechanism (48) provides a more precise control of automatically stopping one actuator while simultaneously operating the second actuator.

Abstract: A manually operable hydraulic selector valve includes a plurality of two-way spool valves which are normally closed and are selectively shiftable individually or in pairs by a joy stick operator to open positions whereby motive fluid can be delivered to a given instrumentality such as the jack cylinder of a construction crane outrigger arm. The joy stick carries a conical disc which cammingly engages drive pin extensions of the individual spool valves. A positive stop for the conical disc is afforded by contact of the disc with the mounting plate of the selector valve. The selector valve is employed with an associated two-way directional control valve.

Abstract: Method and apparatus for hydraulically controlling subsea well equipment, such as valve operators, connectors, and other hydraulically actuated devices, with a significantly smaller number of hydraulic pressure source lines from the surface to the subsea location of said well equipment and for providing return signals to indicate the state of operation of said well equipment using the same hydraulic lines. The apparatus includes a plurality of hydraulic AND-gate logic elements and a plurality of hydraulic valves mounted near the well equipment. A pair of hydraulic lines between the hydraulic valves and a surface vessel or other surface facility provides control for the various valve operators, connectors and other hydraulically actuated devices, while a third hydraulic line provides power to operate the various devices. The same pair of control lines can be used to transmit signal information from the various devices on the sea floor to the surface vessel to indicate the operating status of these devices.

Abstract: A hydraulic control system for a mine roof support unit has a control valve assembly for controlling the hydraulic appliances of the unit, and an actuator for actuating the control valve assembly. The actuator has a valve block provided with a plurality of pairs of spool valves. The spool valves of each pair are detachably fixed in a pair of generally parallel bores formed in the valve block. Each pair of spool valves is provided with a respective rocker arm for actuating purposes. Each of the rocker arms is mounted on a respective cover plate, which covers the mouths of the corresponding pair of bores, and which is detachably secured to the valve block.

Abstract: The present invention utilizes a power system based upon the use of compressed air. Each wheel of the vehicle is provided with a motor which is operated by compressed air from a respective storage tank through a system of valves and hydraulic or fluid pressure lines. The rotation of each wheel is also utilized to drive air compressors which may recapture some or all of the air which is exhausted from each motor and additionally to compress and store air brought in from outside of the vehicle during its motion. The present invention can be adapted for two-wheel drive or four-wheel drive.The drive units for each wheel are substantially identical. The rear units are mounted on fixed axles whereas the front units are mounted on an axle having a universal joint therein and each wheel is mounted by means of a ball joint to a suspension frame which in turn is secured to the vehicle frame.

Abstract: A hydraulic control system is provided for a mine roof support assembly constituted by a plurality of roof support units positioned side-by-side. The control system comprises a respective control valve assembly having a plurality of similar control valves each of which controls a respective hydraulic appliance associated with the corresponding roof support unit. Each control valve can be actuated optionally by an actuator mounted on either one of the two adjacent roof support units, or by either one of two actuating devices mounted one on each of said two adjacent roof support units. Each control valve includes two servo valves having a pair of first and second axially aligned servo-pistons which are separate and independently operable with respect to each other.

Abstract: A manually operable hydraulic selector valve includes a plurality of two-way spool valves which are normally closed and are selectively shiftable individually or in pairs by a joy stick operator to open positions whereby motive fluid can be delivered to a given instrumentality such as the jack cylinder of a construction crane outrigger arm. The joy stick carries a conical disc which cammingly engages drive pin extensions of the individual spool valves. A positive stop for the conical disc is afforded by contact of the disc with the mounting plate of the selector valve. The selector valve is employed with an associated two-way directional control valve.

Abstract: A single lever control system for controlling the operation of multiple functions. A single control lever is coupled through linkage to effect individual movement of a plurality of valve spools in a hydraulic system and is supported for movement in predetermined paths to effect operation of the controls for the hydraulic system. Movement of the control lever effects operation of the hydraulic system in response to movement of the lever in a predetermined path.

Abstract: A loader/backhoe hydraulic system and control valve assembly therefor characterized in that each of a plurality of directional control valves is operative through an associated selector valve to control the operation of either of a pair of cylinders connected to said selector valve. The loader/backhoe herein is further characterized in that the control valve assembly and oil tank are unitized and mounted under the floor of the tractor for simplified piping and access for servicing.

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.