Abstract: An electronic bucket positioning and control system for a vehicle of the type including a hydraulically controlled boom assembly and bucket. The bucket positioning and control system can operate in a bucket positioning mode, bucket return to position mode, bucket anti-rollback mode, and tilt cushion mode.

Abstract: A controller having an up/down switch for changing the rotational speed of a prime mover such as an engine, an actuator such as an electric motor for driving a governor on the basis of the operation of the up/down switch so as to control the rotational speed of the prime mover. A target speed is calculated on the basis of the operation of the up/down switch, and the prime mover speed is controlled by using the calculated value. Another switch is provided to immediately shift the prime mover speed to a speed previously set as desired. This shift switch is used to control the prime mover so that the prime mover rotates at the set speed, and this speed is adjusted by operating the up/down switch.

Abstract: The invention relates to a method and a device for reducing the piston speed in a piston and cylinder assembly (1), as the piston approaches the end position. The piston end position is sensed, and a signal is generated for starting the end position dampening. Dampening is effected in two steps. In the first step (14), a time delay is provided and in the next step (15), the actual braking (retardation) of the piston is effected.The invention also comprises an electronic braking device comprising a dampening activation unit (13) which is connected to transducers (6), a braking delay unit (14) connected to the unit (13) and also to the control lever (5) at issue and a reference signal source, as well as a braking unit (15) connected to the delay unit (14) and adapted, upon activation, to provide a signal (U) to a setting system (3) for controlling the supply of pressure fluid to the piston and cylinder assembly (1).

Abstract: A control device for a power shovel having a first boom, a second boom and an arm rotatable around the longitudinal axis of the arm, detects the angle of the arm with respect to the horizontal plane based on the posture angles of the first and second booms and the arm, and controls the arm cylinder such that the angle of the arm with respect to the horizontal plane is held to a reference angle. Further, the control device detects a deviation angle between the current direction and the initial directions and controls the revolution angle of the arm so as to make the deviation angle zero. Furthermore, the control device designates a moving direction of the connection point between the second boom and the arm along a plane including the first boom, the second boom and the arm, and controls cylinders for the booms such that their connection point may be moved in the moving direction thus designated.

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 control for an excavator controls the position of the bucket cutting edge to a desired depth accurately by a calibrating laser receiving mounted on the excavator stick member and passed through a stationary laser plane wherever the stick is moved into or out of a trench. Linear position encoders monitor the length that the actuating cylinders are extended and lookup tables convert the encoder outputs to angle representations for determining the positions of the laser receiver and the cutting edge. Other lookup tables are utilized to avoid time-consuming iterative calculation procedures to provide real-time digital process solutions of trigonometric functions. The apparatus includes a unique laser receiver comprising a plurality of linearly aligned photo receptors with associated circuitry for producing an output representative of the receptor illuminated or, if a group of receptors are illuminated, the centermost receptor illuminated.

Abstract: An engine override control for an engine (10) which drives a vehicle transmission (18) and an auxiliary variable displacement pump (20) and which is operable to increase engine speed beyond a set engine speed command to increase flow from the auxiliary pump which has reached maximum displacement at said set engine speed under the control of flow-compensator control (60). A valve (31) controls the delivery of fluid from the pump to a load (34) and associated orifices (42a) and (43a) establish a pressure differential between the pressure of fluid supplied by the auxiliary pump (20) and the operating pressure applied to the load. A cylinder (80) responsive to the pressure differential acts on a control member (12) for the engine governor to increase the speed of the engine when the pressure differential falls below a predetermined value.

Abstract: A control system for a working machine which has a boom equipped with a working implement at its forward end and pivoted to a vehicle body movably about a vertical axis, and control valve for controlling the movement of the boom. The system comprises a variable resistor for setting a target position where the boom is to be stopped to produce a setting signal, a sensor for detecting the moved position of the boom to produce a detection signal, differential device for determining the difference between the setting signal and the detection signal to produce a difference signal, a detector for detecting the direction of movement of the boom from the magnitude of the difference signal, a pulse-width modulator for subjecting the difference signal to pulse-width modulation to produce a pulse signal, and a driver for driving the control valve by the pulse signal in the detected direction in proportion to the difference signal.

Abstract: An electronic bucket positioning and control system for a vehicle of the type including a hydraulically controlled boom assembly and bucket. The bucket positioning and control system can operate in a bucket positioning mode, bucket return to position mode, bucket anti-rollback mode, and tilt cushion mode.

Abstract: An excavator has a number of different hydraulically powered functions that are controlled by a closed center hydraulic system that features a pair of variable displacement, engine driving hydraulic pumps, the displacement of which is responsive to the demands of the system. The flow to the various hydraulic motors is controlled by pilot operated load sensing control valves that direct fluid pressure to a load sensing line when one of the hydraulic motors in the system is being operated. The load sensing line is connected to the control system of the pumps to place the pumps in stroke when a flow of pressurized fluid is required. The flow of the load sensing pressure to the controls for one of the pumps can be optionally disconnected to place said pump in a standby condition and thereby reduce the flow capacity of the hydraulic system at the option of the operator.

Abstract: An excavator has a number of different hydraulically powered functions that are controlled by a closed center hydraulic system that features a pair of variable displacement, engine driven hydraulic pumps, the displacement of which is responsive to the demands of the system. The flow to the various hydraulic motors is controlled by pilot operated load sensing control valves that direct fluid pressure to a load sensing line when one of the hydraulic motors in the system is being operated. The load sensing line is connected to the control system of the pumps to place the pumps in stroke when a flow of pressurized fluid is required. The flow of the load sensing pressure to the controls for one of the pumps can be optionally disconnected to place said pump in a standby condition and thereby reduce the flow capacity of the hydraulic system at the option of the operator.

Abstract: The present invention is concerned with an apparatus for controlling an engine mounted on a wheeled type construction machine. This engine controlling apparatus is adapted to set first and second torque performances conformable to a time of working of the wheeled type construction machine and a time of moving of the same and control an output torque of the engine in accordance with the aforesaid first and second torque performances at a time of working and a time of moving. Accordingly, by employing this controlling apparatus, working ability and moving ability of the wheeled type construction machine can be improved compaired with conventional apparatuses which control the engine on the basis of a single kind of torque performance.

Abstract: An improved forklift device for unloading palletized articles from the bed of a flatbed truck may be removably carried in "piggyback" fashion on the rear end of the truck. The device has a fork structure adapted to liftingly engage one of the pallets, a wheeled, ground-supportable frame, and an articulated linkage structure which interconnects the frame and the fork structure and is movable between a fully lowered and rearwardly retracted position and a fully raised and forwardly extended position. The forklife may be propelled along the ground by an engine-driven hydraulic drive system, and is also provided with a hydraulic actuating system for pivoting gantry and boom portions of the linkage, and pivoting the fork structure relative to the linkage. In unloading the articles the fork structure may be moved a substantial distance laterally across the truck bed to liftingly engage the pallet of an article on the far side of the bed.

Abstract: An apparatus determining relative positions of arm elements of a manipulator having at least two relatively moveable arm segments uses image analysis and a model of the manipulator to analyze an image of the two arms to determine the joint angles between adjacent arms.

Abstract: An automatic speed stage changing apparatus for a wheel loader is intended to control shift-down of the wheel loader when a bucket is caused to plunge into an object to be digged such as a hill-shaped earth mass or the like, and an angle suitable for digging work is previously set with respect to a boom angle and a bucket angle respectively. When both the boom and the bucket assume said set angle during forward movement toward the hill-shaped earth mass, this is detected and thereafter a speed stage is automatically shifted down from the selected existent speed stage to a lower speed stage at which a tractive force is increased in accordance with an output of said detection.

Abstract: A crowd control system for a hydraulic loader having three hydraulic pressure sensing switches that are electrically coupled to an electronic controller for overriding the operators commands and decreasing forward driving force when excessive crowding force is detected. The first switch is fluidically coupled to the output side of the hydraulic lifting pump. The second switch is fluidically coupled to the output side of the hydraulic lifting pump. The third switch is fluidically coupled to the extension input side of the boom-lift hydraulic actuator. When hydraulic fluid pressure exceeds the preset levels of each switch, the switches signal the electronic controller which overrides the operators controls and decreases the fluid output of the driving pump reducing the forward drive of the loader and decreasing crowd. The controller will maintain this decreased fluid output of the driving pump until either the second or third pressure sensing switch senses a decrease in fluid pressure below its preset level.

Abstract: An implement has ground working tools mounted thereon moved by hydraulic motors and cylinders with each of the hydraulic motors and cylinders being adjusted through a main control valve. The main control valves are, in turn, controlled by two sets of valves, one set being pilot valves manually adjustable at an operator's station on the vehicle and the second being electrohydraulic valves controlled from a remote area by radio signals received by a radio receiver on the vehicle. Safety switches are provided on the vehicle to block transmittal of the radio signals. The vehicle has a television camera mounted externally of the vehicle cab and directed internally thereof. The camera transmits images to a television screen at a remote area.

Abstract: An engine of a construction vehicle is controlled by a system which includes an engine control operation transmitting mechanism having a loose spring means and connecting a fuel control lever and a governor control lever; a decelerator cylinder accommodating a piston therein and having a spring for biasing always the piston on the opposite side of a pressure chamber defined thereby and on the side of the spring a piston rod connected through a york having an elongated hole formed therein to said transmitting mechanism; a solenoid valve adapted to supply the fluid under pressure delivered by a hydraulic pump driven by the engine for exclusive use in control of the system into the pressure chamber of the decelerator cylinder, and cut off the fluid supply; and an electric circuit for controlling the solenoid valve.

Abstract: A pressure relief system for the primary hydraulic system of a large industrial machine wherein the biasing force biasing one of the pressure relief valves is supplied by the pilot hydraulic control system of the machine. A two-position valve is used to selectively change the biasing force in response to a temperature indicator. The two-position valve couples and decouples the pressure relief valve to and from the pilot control system hydraulic pump and the pilot hydraulic system sump. If the pressure relief valve is in communication through the two-position valve with the pilot hydraulic fluid sump, the biasing force is reduced against the pressure relief valve and the pressure in the primary hydraulic system opens the pressure relief valve and directs hydraulic fluid to the primary hydraulic fluid sump.

Abstract: An electrohydraulic system includes a plurality of electrohydraulic devices individually controlled by microprocessor-based control electronics. The device controllers are connected in common by a bidirectional serial data bus to a master controller for coordinating operation of the various devices. Internal programming within the master controller establishes a repetitive time-sequence of windows for communications with the various device controllers for downloading control signals and parameters, and for uploading data indicative of system status and operation. The various device controllers include internal programming for operating the associated hydraulic devices as a function of control signals and parameters received from the master controller.

Abstract: An engine interlock control system is disclosed which is particularly suited for use with a material handling implement comprising a combination loader backhoe. In the preferred form, the present control system includes an electrically-operated fuel solenoid for selectively controlling delivery of fuel to the internal combustion engine of the implement. This system further includes means for sensing operation of the engine, preferably comprising an oil pressure sensor, and means for sensing disposition of the implement's transmission in a neutral condition. The fuel solenoid, engine sensor, and transmission sensor are all operatively connected with a microprocessor control unit, whereby delivery of fuel to the engine is prevented in the event that the engine is not running, and the transmission is in a non-neutral condition.

Abstract: In a diesel for a hydraulic excavator or the like, the speed regulator of the injection pump is set by a lever which is pivoted by a piston-cylinder unit against the force of a return spring. Before or during operation under load, the piston-cylinder unit brings the setting lever to a preselected load position and, after terminating or interrupting operation under load, moves it to its idling position. At least one handle of the control levers for the hydraulically movable implements of the excavator is provided with a switch which, on first actuation, so operates a magnetic valve that the piston cylinder unit or the return spring moves the setting lever to the load position and, on being actuated again, returns the setting lever to the idling position.

Abstract: An apparatus for controlling the engine of a hydraulically driven vehicle includes a transmission mechanism having a loose spring and connecting a fuel control lever operationally to a governor control lever, a decelerator cylinder including a spring having a slightly larger spring force than the loose spring and disposed on the opposite side of a piston from a hydraulic fluid chamber and a piston rod connected to the transmission mechanism by a yoke having a slot, an electromagnetic valve for supplying a hydraulic fluid from a hydraulic pump driven by the engine to the hydraulic fluid chamber in the decelerator cylinder or interrupting its supply, and an electric circuit for opening or closing the electromagnetic valve.

Abstract: A method of and system for controlling a hydraulic power system comprising an internal combustion engine receiving a supply of fuel from a fuel injection pump, and at least one variable displacement hydraulic pump driven by the internal combustion engine. An engine speed deviation is obtained from the difference between a target speed set by an accelerator operation of the internal combustion engine and an output speed thereof. Then a fuel injection target value in predetermined functional relation to the engine speed deviation, is obtained based on at least the engine speed deviation, and a fuel injection rate of the fuel injection pump is controlled based on the fuel injection target value.

Abstract: An apparatus and process combining an excavation apparatus with a fully contained underground elongated conductive object detector capable of selectively detecting underground objects such as water pipes and electrical cables. The combination of this invention may be advantageously used in trenching to prevent damage to underground water pipes and electrical cables by detecting their presence before the digging implement damages them. An audible or visual signal may be activated and/or the excavation apparatus may be automatically shut down upon detection of an underground pipe or cable a few feet below the excavation. The detector may be incorporated in the digging shovel of a backhoe or maintained in position adjacent the digging implement by a boom extending from the excavation apparatus. Simple and sturdy time gated electronics is advantageously used to differentiate underground pipes and cables from other underground metal debris and to provide range and direction information.

Abstract: The operation of a dragline machine in digging below the earth's surface is monitored to provide measurements of the variations in pull cable length, lift cable length, and main boom inclination. From these measurements, the angle of inclination of the pull cable below the horizontal is determined. The depth of the excavation is then determined from the length of the pull cable and its inclination.

Abstract: A hydraulic circuit system of a construction machine having first and second hydraulic circuit, and a bypass circuit for connecting the first and second circuits together. The first circuit includes a first hydraulic pump and a first valve group having a plurality of directional control valves for controlling a flow of hydraulic fluid from the first pump, and the second circuit includes a second hydraulic pump and a second valve group having a plurality of directional control valves for controlling a flow of hydraulic fluid from the second pump. A plurality of actuators are driven by the hydraulic fluid supplied from the first and second pumps through the valves. The bypass circuit includes a bypass line for connecting the first travel valve in series with the second travel valve in a position downstream thereof through the selecting valve.

Abstract: A remote controlled hydraulic circuit of the type comprising a source of pressurized fluid, a number of hydraulic motors connectible to the source of pressurized fluid, and control means for connecting the source of pressurized fluid to the hydraulic motors, the control means being remotely piloted by a series of pressure signals each of which corresponds to the opening of the connection between the source of pressurized fluid and a respective hydraulic motor. The hydraulic circuit according to the invention includes selector means for establishing priority for supplying pressurized fluid to one or more preferential hydraulic motors. These selector means are intended to detect, when operatively active, pressure signals corresponding to the supply of pressurized fluid to the preferential hydraulic motors and, in this condition, to render inoperative the control means associated with the other hydraulic motors, should they already have been activated to effect the supply of these other hydraulic motors.

Abstract: A parallelogram arm assembly having a vertical arm for suspending a load at lower end thereof and a pair of horizontal arms one of which is guided in a horizontal path is provided. The other horizontal arm is guided in a vertical path. The paths are defined in a supporting structure which is mounted rotatably on a standard or the like. Apparatus, such as a piston/cylinder actuator is provided for maintaining in cooperation with the parallelogram a floating balanced state of the arm assembly independently of the loaded or no-load state.

Abstract: A front end loader in the form of a skid-steer loader which includes a power operated working implement and control apparatus that has a plurality of operative positions for supplying power to the working implement and at least one neutral position where power cannot be supplied to the working implement. The control apparatus is capable of being manipulated by the operator of the loader to place the control apparatus in any one of the selected operative positions or the neutral position. An operator restraint member is mounted on the skid-steer loader and has an engaged position for securing the operator to the operator position during operation of the loader and a disengaged position to permit the operator to enter or leave the loader. A locking member is engaged with the control apparatus when the restraint member is in its disengaged position and is disengaged from the control apparatus when the restraint member is in its engaged position.

Abstract: A servo amplification system is created particularly for heavy construction equipment, but has a general utility that is much broader. The system utilizes a hydraulic analog system with a separate subsystem for each dimension of motion. The operator moves the operative element, such as the backhoe bucket, of the analog replica which ordinarily would be situated in the cab of the backhoe or other piece of equipment. A small hydraulic cylinder operative in response to movement at each articulated connection of the backhoe operates a pilot valve which controls a pilot piston mechanically linked to the drive valve of the drive cylinder of the corresponding articulation in the actual backhoe. A feedback system comprising a mechanical link from the actual drive piston to a feedback cylinder and piston delivers hydraulic fluid back to the inlets of the pilot valve in such a way as to cancel the pilot orders from the initial control cylinder.

Abstract: An operator restraint member having two ends is pivotally mounted at each end to a skid-steer loader. The restraint member has an engaged position for securing the operator to the operator position during operation of the loader and a disengaged position to permit the operator to enter or leave the loader. A friction device is connected to one end of the restraint member to retain the restraint member in the rotative position selected by the operator until repositioned. An automatic lock-quick release latch is connected to the other end of the restraint member for selectively locking the seat bar in its engaged position. A locking assembly is engaged with the control apparatus when the restraint member is in its disengaged position and undergoes pivotal movement to become disengaged from the control apparatus when the restraint member is in its engaged position.

Abstract: A time delay device for the seat interlock mechanism on a skid-steer loader is disclosed wherein the boom structure will not be rendered inoperable for vertical movement, until the passage of a short predetermined period of time after the seat switch has indicated that the operator has left the loader seat. A solenoid valve is operable to stop the flow of fluid to the hydraulic cylinders moving the boom structure along a generally vertical path. A seat switch connected in the electrical circuit to the solenoid valve activates the solenoid valve to stop the fluid flow if the operator leaves the loader seat. The time delay device includes a capacitor, a resistor and a diode in series-parallel with both the source of electrical current and the solenoid valve and prevents the solenoid valve from restricting the flow of fluid through the hydraulic circuit to the boom lift cylinders for a short period of time after the seat switch has indicated that the operator has left the seat.

Abstract: A front end loader in the form of a skid-steer loader which includes a power operated working implement and control apparatus that has a plurality of operative positions for supplying power to the working implement and at least one neutral position where power cannot be supplied to the working implement. The control apparatus is capable of being manipulated by the operator of the loader to place the control apparatus in any one of the selected operative positions or the neutral position. An operator restraint member has two ends and is pivotally mounted on the skid-steer loader at one of its ends. The restraint member is swingably movable between an engaged position for securing the operator to the operator position during rough ride conditions and a disengaged position to permit the operator to enter or leave the loader. A latch is provided to selectively secure the restraint bar in the engaged position.

Abstract: A seat interlock mechanism for a skid-steer loader is disclosed wherein the boom structure can be rendered inoperable for vertical movement if the operator leaves his seat. The hydraulic circuit for powering the hydraulic cylinders, which move the boom structure in a vertical direction, includes a solenoid valve that is capable of stopping the flow of fluid through the hydraulic circuit and, thereby, prevent the boom structure from vertically moving. An improved seat frame structure, incorporating a switch which senses the presence of an operator on the seat, provides greater sensitivity for the presence of the operator, so that the switch can control the solenoid valve to stop or permit the flow of fluid through the circuit. The improved seat frame includes a first member mounted to the loader frame and a second member biased away from the first member by a spring positioned beneath the center of gravity of that portion of the seat being biased upwardly by the spring.

Abstract: A load skidding vehicle (10) utilizing a grapple assembly (28) for grasping loads. The grapple assembly (28) is pivotally connected to a boom (24) which extends rearwardly from and is connected to a chassis (12). The grapple assembly (28) is pivotable relative to the boom (24) by a hydraulic cylinder (36) connected to the grapple assembly (28) and chassis (12). Displacement of the hydraulic cylinder (36) provides pivoting of the grapple assembly (28) to an optimum load skidding position. Means (66,68,70,72,78,62',68') are provided for maintaining the optimum skidding position for the grapple assembly (28) with a biasing force during skidding by permitting the grapple assembly (28) to pivot away from the initial skidding position when a predetermined skidding force is encountered. When the skidding force falls below the biasing force magnitude, the grapple assembly (28) is again pivoted toward the initially set skidding position.

Abstract: A semi-automatic hydraulic excavator capable of automatically controlling arm and bucket angles when bringing the bucket back to the original excavation posture after completion of dumping excavated soil. For this purpose, arm and bucket angle detectors are provided therein and the automatic control is performed by negatively feeding back values detected by these detectors to minimize deviations between these values and preset values produced from arm and bucket angle setters corresponding to the arm and bucket angles in the original excavation posture. The automatic control mode is selected by a signal from an automatic control command signal producing circuit. With this system, the bucket is swiftly brought back to the original excavation posture from the dumping posture without requiring much operator's skill and efforts.

Abstract: A system for automatically regulating the fuel supplied to the engine of a mobile construction machine which has a hydraulic pump driven by the engine. A tool is carried by the machine for performing work functions and hydraulic cylinders are provided for manipulating the tool responsive to pressurized fluid being supplied to the hydraulic cylinders. A manually operated valve mechanism is provided for controlling the flow of hydraulic fluid between the hydraulic pump and the hydraulic cylinders. A lever arm regulates the flow of fuel to the engine. The lever arm can be manually manipulated or it can be manipulated automatically by means of a double action cylinder. A piston rod extending from the double action cylinder is connected to the lever arm so that the fuel supplied to the engine is regulated responsive to changes in pressure in the hydraulic system.

Abstract: A drive system for construction machinery in which hydraulic circuit is provided with a plurality of variable-displacement hydraulic pumps and a plurality of hydraulic actuators, each pump being connected in closed circuit to one or a plurality of the actuators via a solenoid-operated valve or valves to drive a movable member or members connected to the actuator or respective actuators when pressurized fluid is supplied to the actuator or actuators from the pump. At least one of the selected hydraulic actuators is further connected in closed circuit through a solenoid-operated valve to at least one of the hydraulic pumps other than the hydraulic pump which is connected in closed circuit to the hydraulic actuator. The hydraulic circuit means is controlled such that timing for switching the solenoid-operated valves is controlled in conjunction with the operation of the pump so as to absorb the shock which would otherwise be produced when each actuator is rendered operative and inoperative.

Abstract: The control device for an earthwork machine according to the invention is designed for reducing the manufacturing cost of the earthwork machine by eliminating some of the calculating circuitry and the control circuitry. According to the control device, one of the cylinders necessary for carrying out straight excavation is directly manually controlled without using calculating circuitry, and the operations of the cylinders are respectively detected by detecting circuitry. The other two cylinders are also controlled by the arithmetic unit provided in the control device for performing calculation necessary to move the sharp edge of the bucket along a straight line of predetermined inclination in accordance with detected pivoted angles of the boom, arm and bucket.

Abstract: A bucket assembly and operating system for a conventional front end loader that increases the dump height for a given boom length. The bucket assembly includes a cradle pivotally attached to the end of a boom and a bucket rotatably supported by the cradle. Rotative movement in the cradle and bucket between rollback and dump positions is accomplished by fluid pressure operated actuators controlled by a fluid pressure control system. Sequence valves forming part of the control system are utilized to delay the application of fluid pressure to certain actuators so that sequential motion in the cradle and bucket is achieved without the necessity of additional operator controls. A bucket latching mechanism mechanically locks the bucket in its rollback position until the bucket dump sequence is initiated.

Abstract: A control (51, 151) for automatically effecting a lock-out of an interaxle differential (14) of a wheeled vehicle (10). The control is arranged to sense a deflection of one of the axles (22) of the wheeled vehicle utilizing a springy beam (24, 124) mounting for transmitting a sensible signal through interconnecting structure (36, 136, 38, 50) from the deflectable beam to the lock-out lever (37) of the interaxle differential (14). In one form, the beam is made to be springy by being provided with a tapered end portion (32) connected through the linkage (36) and in another form, the beam connection to the linkage (136) is through a leaf spring (152). A stop (155) may be provided for limiting the deflection of the axle being sensed.

Abstract: A portable load handling apparatus includes a vehicle having a frame, and an elongated boom arm connected to the frame for pivotal movement about at least a first horizontal axis. The boom arm may pivot about a first vertical axis and be extendable and retractable as well. A load support member is connected to the boom arm by a wrist mechanism for pivotal movement about at least first and second generally perpendicular axes and may be pivotal about a third axis perpendicular to the first and second axes. A primary power source is actuatable to pivot the boom arm about the first horizontal and vertical axes and to extend and retract the boom arm and a secondary power means is actuatable to pivotally move the support member about the first, second and third axes. A control mechanism includes a control arm connected to the frame for pivotal movement about at least a second horizontal axis, with the control arm preferably pivotal about a second vertical axis and extendable and retractable as well.

Abstract: A backhoe includes a computer capable of automatically controlling the depth or lowermost point of the backhoe bucket. The computer is programmable to provide level operation of the backhoe, will have preset common depths and programmable depths, and further include an automatic empty and return cycle, and to maintain a given level or slope of a desired ditch. Special resistors are positioned at all of the pivot points of the backhoe to act as sensors for relaying information to the computer. The output of the computer controls hydraulic valves which, in turn, operate the outriggers, boom, crowd and bucket of the backhoe assembly.

Abstract: A safety control system for a crane adapted to prevent exceeding the uppermost safe elevation of each articulated section of a boom and the safe swinging limits right and left of the boom, which is also adapted to allow the crane operator to preset the safe limits without tools and without leaving the cab of the crane, and wherein the conventional manual controls are disabled to solely allow the required enabling to bring back the boom in the fully operative range. This safety control system preferably includes an electrical elevation sensor for each of two articulated boom sections, an electrical swinging sensor discriminating between left and right safe swinging limits, a warning device indicating the arrival at a limit, a 3-way solenoid valve to regulate the supply of hydraulic fluid to the boom elevation and swinging actuators, and to the conventional manual controls, and relays to control the energization of the 3-way valve, the warning device, and a brake to stop swinging of the boom.

Abstract: A loader vehicle includes a loading implement movable to a dump and a rack-back position by means of actuation of cylinders. The movement of the cylinders is provided by fluid control valves in turn operated by actuator means which provide for both a slow dump and a fast movement of the implement.

Abstract: A control apparatus is disclosed for permitting simultaneous actuation of a plurality of fluid motors whose combined flow capacity exceeds the available flow rate. The plurality of fluid motors are actuated by a corresponding plurality of open center, pressure-compensated, pneumatically actuated control valves which are connected in series flow arrangement with a fluid supply having a fixed minimum flow output and a maximum flow rate output. A device is provided to sense the rate of flow for hydraulic fluid exhausting from the series of control valves. The rate of flow sensing device controls a pneumatic pressure regulator that provides a corresponding pressure change in the pneumatic supply pressure provided to a plurality of control valves.

Abstract: A loader vehicle includes a loading implement movable to a dump and a rack-back position by means of actuation of cylinders. The movement of the cylinders is provided by fluid control valves in turn operated by means which provide for both a slow dump and a fast dump movement of the implement, with fast dump movement initially selected being automatically changed to slow dump movement dependent on the position of the implement.