Abstract: A lock for holding a boom in a storage position on a boom support is disclosed herein. The lock consists of a first member or vertical pin that is carried by the boom support, a second member or locking ring that is pivoted on the boom about a horizontal axis and that has an opening for receiving the first member, and a deformable biasing element or spring interconnecting the first and second members. The second member is biased to a first position by the spring and engages the vertical pin when the boom is moved to its storage position. When the opening in the locking ring and the vertical pin are axially aligned, the spring returns the second member to the first position latching the first and second members together.

Abstract: A vehicle for removing slash from steep logging slopes includes an anti-skid propulsion system characterized by a power winch for reeling in an uphill-anchored cable and a pair of crawler tracks (or large tires) driven in synchronization with the winch. The vehicle has an articulating tail boom for working against the cable to assist in maneuvering the vehicle along the slope and stabilizing the vehicle during slash gathering operations. A knuckle boom which is extendable from the vehicle has a grapple for gathering slash within a relatively large area around the vehicle. Removal of slash from the operating site of the vehicle is accomplished by transporting the slash to an access landing using a mobile slash wagon or by chipping the slash using a chipper mounted on the vehicle and then pneumatically carrying the chips through a pipe to a storage van at an access landing remote from the vehicle.

Abstract: The use of a lift fork for a boom swinging vertically over 240.degree. is made feasible by hanging the lift fork with freedom to pivot as gravity dictates when the angularity of the boom is changed, with a brake by which the angularity between boom and lift fork can be locked. The brake enables the boom to exert a strong forward thrust on the bottom of the lift fork when this is necessary for thrusting its tines under a load, and has other advantages. Proper positioning of the load on the forks will cause the forks to hang with the tines of the forks nearly level, or slightly tilted back if preferred. Prefably the fork-lift device also hangs conveniently close to this position when empty. Material handling programs which heretofore needed not only a crane operator but a crew for attaching the hoist line to the load and removing it, can be performed by the operator alone if the swinging but lockable lift fork is used with a three-part "reach anywhere" articulated boom on a swinging crane.

Abstract: This invention relates to a public works machine such as a self-propelled hydraulic shovel. This machine comprises a lower chassis provided toward one end with a pair of carrying wheels mounted on wheel-carrying arms that may be adjusted and raised, and toward the other end with raisable stabilizers. A superstructure is mounted on this lower chassis by a positioning ring. The superstructure carries, on the one hand, working equipment of the machine and, on the other hand, a pair of carrying wheels mounted on raisable arms. The control of the machine is effected by pivoting of the two parts about the positioning ring. This machine permits travelling on uneven ground while the machine remains level.

Abstract: A backhoe arrangement is described wherein overcenter forward movement of the boom and boom cylinder provides a transport configuration for the backhoe, and the backhoe operator's view of the bucket is enhanced. A swing tower is attached to the rear of the machine and serves as a support that embraces an asymmetrically mounted or offset boom assembly wherein the longitudinal axis of the boom and the longitudinal axis of the hydraulic actuator operating the boom are offset from the vertical axis of rotation of the swing tower. The boom hydraulic actuator flanks the boom in a clearance relationship that permits the boom to assume a substantially vertically directed neutral intermediate position. An offset boom and actuator improves the center of gravity of the backhoe and allows the boom actuator to be protected by the boom.

Abstract: A vehicle for removing slash from steep logging slopes includes an anti-skid propulsion system characterized by a power winch for reeling in an uphill-anchored cable and a pair of crawler tracks driven in synchronization with the winch. The vehicle has an articulating tail boom for working against the cable to assist in maneuvering the vehicle along the slope and stabilizing the vehicle during slash gathering operations. A knuckle boom which is extendable from the vehicle for gathering slash within a relatively large area around the vehicle and preparing the soil for planting. A slide mechanism is disposed at the end of the knuckle boom for selectively varying the overall length of the boom. The slide mechanism includes a pair of claws which can be operated as a grapple for gathering slash or as a rake for scarifying the forest soil. The slide mechanism can be tilted for optimum orientation of the claws during raking.

Abstract: A waste receptacle dumping mechanism. The receptacle dumping mechanism of the present invention comprises a vehicle mounted cylinder actuated mechanism for engaging and translating waste receptacles from a first position in front of the vehicle to a second position over a waste receiving opening associated with a vehicle container. A cylinder is provided for tilting and emptying the receptacle once it has been placed above the opening. The mechanism of the present invention provides improved adjustable stabilizer rods which provide for accurate engaging of the dumping mechanism with the waste receptacle as well as extending the life of the mechanism and reducing the amount of down time for repairs.

Abstract: A hydraulic actuator and control for positioning the boom of a backhoe mounted on the rear of a tractor that smoothly decelerates the boom at the limits of its horizontal swinging movement. A directional control valve ports fluid to two double acting hydraulic actuators positioned in opposed relation on the tractor to drive the boom from side to side. The boom is cushioned at the limits of its travel, whether or not the operator releases the operating pedal for the directional control valve, by blocking discharge flow from a contracting actuator to the directional control valve and porting this discharge flow over a pressure relief system that is independent of the directional control valve. The pressure relief system provides substantially constant deceleration of the boom without high peak pressure in the actuator by using a lower pressure relief valve in the actuator cylinder heads arranged in series with a higher pressure relief valve that discharges directly to tank.

Abstract: A unique hydraulic circuit is provided for converting rectilinear motion to rotational motion about an axis through the use of two pivotally mounted hydraulic motors. The hydraulic motors are pivotally interconnected between a pivoting member and a fixed member. A source of hydraulic fluid under pressure is directed to each hydraulic motor by a conduit system incorporating a flow control valve and a sequencing valve. The flow control valve selectively delivers fluid power to the hydraulic motors to rotate the pivoting member in one direction or the other. The sequencing valve senses the angular position of the two hydraulic motors and redirects the flow of fluid to the hydraulic motors in such a manner as to maintain the torque applied to the pivoting member relatively constant. The sequencing valve acts to redirect the flow of hydraulic fluid to the hydraulic motors so that only one of the hydraulic motors is pressurized at the end of the arc of swing of the pivoting member.

Abstract: A hydraulic excavator has a bucket actuating and control linkage comprising a boom pivotally connected at one end to a self-propelled vehicle, a stick pivotally connected at one end to the other end of the boom, and a bucket pivotally mounted on the other end of the stick. A pair of hydraulic cylinders for actuating the bucket are pivotally connected to the boom via a pair of bucket attitude control bellcranks, respectively. By adjustment of the angular position of the bucket attitude control bellcranks relative to the boom, as by another pair of hydraulic cylinders, the bucket can be conditioned for a level crowd attitude, crowd-to-carry attitude, or crowd-to-dump attitude.

Abstract: Hydraulic excavator in which the support means for the bucket allows lateral excavation over considerable lengths. This means comprises: a fastening element solid with the excavator arm; a first and a second bearing structures hinged to each other as well as to the fastening element and to the bucket, respectively; a tie-rod connecting the second bearing structure to the fastening element; means for moving the first bearing structure with respect to the fastening element and the bucket with respect to the arm; and means for adjusting the angular position of the tie-rod with respect to the first bearing structure.

Abstract: A machine for cleaning out or dredging out ponds, marshes, or canals, comprises a central longitudinally extending fluid-tight cylindrical body having a low coefficient of friction with the ground and provided with withdrawable stabilizing feet. The base of the body is beveled at both ends. An excavating shovel, having two articulated arms actuated by cylinder devices, is mounted on each end of the body and pivotal through at least 180.degree. about a vertical axis from one lateral side of the body to the other under the control of another cylinder device. The two shovels act as excavating devices or as devices for axially displacing the machine over the ground or laterally displacing the machine over the ground in combination with the stabilizing feet.

Abstract: Swing motors employed on backhoes and like constructions vehicles are interconnected between a tractor frame and a mast frame to selectively rotate the mast frame relative to the tractor frame. In addition to posing assembly and disassembly problems, conventional mounting arrangements for swing motors of this type oftentimes subject various spline connections, pins, and bearings to undue wear. The swing motor mounting arrangement (10) of this invention overcomes the above problems by providing a pair of first brackets (20) fro pivotally mounting a mast frame (15) on a tractor frame (16) and a pair of second brackets (26) for securing opposite ends (14) of a shaft (13) of a swing motor (11) to the mast frame (15). A housing of the swing motor (11) is connected to the tractor frame (16) whereby pressurization of the motor will rotate the shaft (13) relative to the housing (12) to selectively swing the mast frame (15) relative to the tractor frame (16).

Abstract: A combination of two pins and two lock rings are used to restrain the motion of a vehicle based boom having the ability to rotate in both the horizontal and vertical directions. Each lock ring is a plate like structure having a hole to receive the corresponding pin. One plate is attached to the boom; the corresponding pin is attached to the boom support. The second plate is attached to the vehicle body; the corresponding pin is attached to the boom support. A single control lever is provided so that the boom operator may actuate the lock rings and unlock each one in sequence.

Abstract: An excavator having a boom with slidably engaging base and beam parts is disclosed. The base part is mounted on a support part of the excavator for rotation about a horizontal axis; and a dipper arm which carries an excavating tool is pivotally suspended from the beam part. The base and beam parts are joined by channel section guides which permit sliding movement between the parts. A wedge member releasably fixes the relative position of the base and beam parts by wedgingly engaging both parts.

Abstract: A pair of connection devices serve as the upper connection between a traction vehicle such as a skid steer loader and an accessory apparatus such as a backhoe. Each connection device includes an anchor element including an anchor element outer end extending from the traction vehicle towards the accessory apparatus and a channel element including a channel element outer end extending from the traction vehicle and towards the accessory apparatus. The anchor element outer end and the channel element outer end have a selectively engaged position for connecting the accessory apparatus to the traction vehicle. A sleeve member is slidably disposed over and operatively connected to the channel element for movement thereon. The sleeve member has a surface adapted for selective locking contact with at least one of the outer element ends for retaining the element ends in an engaged position.

Abstract: In a power shovel having a main frame, a front end assembly operatively connected to the main frame and a rope crowd system including a rope drum supported on the main frame, a motor supported on the main frame drivingly connected to the rope drum, a brake operatively connected to the rope drum and a rope wound on the drum and operatively connected to the front end assembly, a system for preventing the rope from becoming slack comprising apparatus responsive to an impending slack condition of the rope for actuating the drum brake thereby preventing continued pay out of the rope by the drum and apparatus responsive to motor torque in a pay-out direction for disengaging the motor from the rope drum, allowing the motor to continue to operate in the pay-out direction when said drum brake is actuated.

Abstract: A device for locking a boom to a boom support structure as used in earthworking implements is described. A lug having a camming surface is provided on the boom or on the boom support structure as the case may be. The opposite structure is provided with a pivoted arm joined to a lock pin. Motion of the boom toward the boom support structure engages the lock pin and camming surface. Continued movement boom toward the boom support structure forces the lock pin over the lug. Subsequent movement of the boom away from the boom support structure so as to separate the two is prevented by virtue of the lock pin engaging the back side of the lug. A pull cable actuated by the equipment operator disengages the lock pin from the cam thereby permitting free movement of the boom and boom support structure. A bias spring maintains the pivot arm and lock pin in one position unless the lock pin engages the camming surface of the lug.

Abstract: The crane or excavator includes a revolving superstructure which is supported on a carrier frame for rotation about a vertical axis by means of a turntable. The superstructure carries a linear hydraulic motor which includes a downwardly directed, normally retracted, piston rod having a support pad at its lower end. A secondary ground engaging frame positioned endwise of the carrier frame includes an upper reaction surface. The main frame includes a side positioned shelf also having an upper reaction surface. Both reaction surfaces are within the swing path of the linear hydraulic motor. In operation, the linear hydraulic motor is positioned over one of the reaction surfaces and the piston rod is extended into a load transferring contact with the reaction surface.

Abstract: The invention relates to a power arm made of a bent, welded structure defined by two lateral plates and by an upper plate and a lower plate welded to the lateral plates and comprising a box having an upper cap and a lower base forming a cross piece of width equal to the spacing of the lateral plates, disposed between these plates in the zone of their elbow and welded to said plates. The cap and the case join, forming two angles, along two lines which pass substantially through the neutral axis of each lateral plate. The invention finds particular application in the manufacture of the boom of a hydraulically operated shovel.

Abstract: A machine comprising a rotatable telescopic boom assembly includes an outer boom section, an intermediate boom section rotatably mounted within the outer boom section, and an inner boom section located within the intermediate boom section on a telescopic relationship thereto. The inner boom section is adapted to carry an implement such as, for example, an impact hammer, at one end thereof. A mounting is provided to which the outer boom section is rigidly attached. Fluid actuating means are also provided for rotatably driving the intermediate boom section within the outer boom section continuously through 360.degree. in one direction of rotation and for reciprocating the inner boom section within the intermediate boom section.

Abstract: In a backhoe type of excavating apparatus comprised principally of: a main arm or mast fulcrumed at one end from a rear platform of a tractor; a second hydraulically articulated arm, or so-called dipper stick, supported by and pivoted on the free end of the main arm; and a trenching or digging bucket pivotally attached to the free end of the dipper stick and being hydraulically articulated to provide a swinging or curling motion thereto, an improved dipper stick constructed of telescoping sections for extending or shortening the length thereof in response to an internally contained hydraulic actuator and including at its mast supported end a hydraulic rotator assembly whereby the dipper stick (and attached digging bucket) may be rotated over approximately 150.degree. in each direction from its normal vertical orientation.

Abstract: A pressure-fluid supply system for use in a hydraulic loader device. Included in the device are a mast mountable on a truck, a platform rotatably mounted on the upper end of the mast, and hydraulic fluid-operated equipment carried on the platform for rotation therewith. The supply system includes a pump anchored on the platform, for supplying hydraulic fluid to the equipment carried thereon, and an engine mounted on the mast. The engine's power output is drivingly coupled to the pump about the platform's axis of rotation, wherein the platform may be rotated endlessly during pump operation.

Abstract: A releasable locking mechanism for holding a boom in a stored position on a support consists of a latch pivotally supported on the boom and normally held in a first position with a pin carried by the swing tower and aligned with the latch. The pin and latch are positioned such that movement of the boom to the stored position will automatically pivot the latch and produce an interlocking relationship. The release mechanism consists of first and second pivotally interconnected elements, one of which is supported along the pivot axis for the swing tower on the vehicle and the second element having a control member extending therefrom to the operator's station. A universal connection is provided between the control member and the second element, and is located along the vertical pivot axis for the swing tower.

Abstract: The vertically swingable boom of the apparatus is articulated to present a joint that is spaced outwardly from the horizontal swinging axis of the lift cylinder for the boom. A rigid link transversely and pivotally interconnects the lift cylinder and the inner section of the boom to control articulation of the latter about the joint during swinging of the boom. Consequently, the moment between the line of action of the lift cylinder and the boom remains favorably high at all locations on the path of swinging travel of the boom and the lift cylinder can swing through an arc approaching 180.degree. during its operation of the boom.

Abstract: A front end mechanism for an excavating machine is shown having a boom pivotally mounted at its foot and a dipper stick pivoted to the forward end of the boom that carries a dipper at its outer end.

Abstract: An upright including upper and lower end portions is provided and support structure is carried by the lower end portion of the upright for support of the latter from one end of a vehicle. A boom including base and free end portions has its base end portion pivotally supported from the upper end portion of the upright for oscillation relative thereto about a horizontal axis extending transversely of the upright and the boom, and motor structure is operably connected between the upright and the base end portion of the boom for oscillating the boom relative to the upright. The support structure on a first disclosed form of the invention is operative to utilize the boom mounting structure of a backhoe for support of the upright from a backhoe vehicle in lieu of the backhoe boom and the support structure on a second form of the invention includes a hitch frame for removably supporting the upright from the three-point hitch of a tractor.

Abstract: A backhoe swing frame has a latch member fulcrumed to the top thereof. When the backhoe boom is in a raised transport position and the swing frame is in a centered position, the latch member may be pivoted to a lock position wherein a pin at one end thereof is received in a downwardly opening hook fixed to the backhoe boom and a block at the other end thereof is received in an upwardly opening channel at the top of the support frame for the swing frame.

Abstract: A power-operated implement mechanism mounted on the tip of a boom. The mechanism includes a torque tube which is rotated under power to rotate an implement mounting. A fluid-operated ram which is actuated to cause opening and closing of work implements in the mechanism has its rod extending downwardly through the torque tube then to be connected through linkage to the work implements. The work implements are pivotally mounted on the implement mounting. The implement mounting is rotated about the axis of the torque tube through power-operated means operatively connected to the torque tube.

Abstract: A hydraulic circuit for supplying fluid to a ram to move an elongated member about a fixed axis on a frame includes a reservoir, pump, valve and conduits connected to opposite ends of the fluid ram. The fluid ram includes a cylinder pivoted on a ram pivot on the frame adjacent to and outside the fixed axis and the elongated axis of the member is moved across the ram pivot as the member is moved between working and transport positions. The hydraulic circuit incorporates a valve element carried by the piston and moved from a seated position at the critical time when the elongated axis is generally coincident with the ram axis to interconnect the two cylinder chambers and assist in moving the axis across the ram axis.

Abstract: A hydraulic circuit construction for a working vehicle operable as a backhoe and also as a dozer, the circuit construction comprising a multiplex valve assembly with a dozer control valve for a dozer system, a motor control valve for one of right and left running systems, and an arm confluence valve for supplying pressure fluid to an arm cylinder of a backhoe system from a pump common to the dozer and motor valves are connected in series with one another to the pump, and a change-over valve is provided downstream from the dozer and the motor valves and upstream from the arm confluence valve for interrupting the supply of the pressure fluid from the pump to the arm confluence valve. The above circuit construction enables the vehicle to perform both operations, namely a bulldozing operation without the vehicle being urged to run obliquely, and a successful running out operation from a marshy ground by an arm operation without any one of the running system being urged to stop by the work load of the arm.

Abstract: A stabilizer assembly for a vehicle with increased lift capability and lateral support, without sacrificing any degree of uprightness during transport, is provided by trunnion mounting the cylinder of a cylinder and piston rod assembly to the frame. An automatic mechanical latching mechansim for securing the stabilizer assembly in an upright position during transport is also provided.

Abstract: In a material handling machine having a turret, a boom supported by the turret for movement about a first pivot, and a piston-cylinder unit for pivoting the boom about the first pivot, the piston-cylinder unit being supported by the turret for pivotal movement about a second pivot parallel to the first pivot, the improvement comprising at least one of the aforesaid pivots being journalled for rotation in the bore of an eccentric sleeve member which is in turn journalled for adjustable rotation in the turret. Rotation of the eccentric sleeve produces a change in the distance between the first and second pivots, with an accompanying variation in the speed-power relationship of boom movement.

Abstract: A releasable boom lock located between a swing tower that pivotally supports a boom consists of a latch pivoted on the swing tower and a pin located on the boom. The pin and latch are designed to automatically interlock the boom and swing tower when the boom is moved to a transport position and are separable from each other by manipulation of a tool fluid ram pivotally supported on the boom. The tool fluid ram has an extension held in a fixed position so that operation of the fluid ram, which causes it to pivot on the boom, will move the extension into engagement with the pivotable latch and release the boom from the swing tower. The extension can be released to be pivotable on the ram to allow operation of the ram without releasing the latch.

Abstract: A locking system for mechanically locking a backhoe boom in a transport position on an earth moving machine. The boom is supported for swinging movement about a horizontal pivot carried on a swing post coupled by a vertical pivot to a frame structure of the earth moving machine. The locking system comprises a lever fulcrummed intermediate its ends on the swing post. The lever has at one of its ends a latching element engageable with the boom in a raised position of the latter to prevent downward swinging movement, and at the other of its ends a latching element simultaneously engageable with the frame structure to hold the swing post and thereby the boom in a centered position. A manipulable actuator accessible at the operator's station is provided for actuating or releasing the boom locking actuator.

Abstract: A toy shovel is provided. The shovel comprises a seat, a first arm pivotally mounted on the seat and extending forwardly therefrom, a second substantially vertical arm pivotally mounted at its upper end on the first arm, a shovel mounted for pivotal movement on the lower end of the second arm, a first handle pivotally mounted on the seat and secured to the first arm for controlling the depth of the cut made by the shovel, a second handle pivotally mounted on the seat, and linkages interconnecting the second handle and the shovel for controlling the pivotal movement of the shovel.

Abstract: An improved method and combination facilitating interchanging attachments on an adaptable off-road vehicle characterized by, in addition to the usual vehicle and its controls, prime mover, power source, drive apparatus, steering apparatus and the like, a first portion of attachment apparatus carried by the vehicle including a plurality of mounting stations on respective front pair of elongate substantially horizontal tracks and front and rear pairs of vertical tracks; the tracks being spaced apart a first predetermined distance; each mounting station having a plurality of apertures that are laterally aligned for even mounting of the attachments; a plurality of attachments, each having respective second portion of attachment apparatus, each second portion including a pair of track engaging clevises laterally spaced apart the first predetermined distance and having a plurality of apertures adapted to align with the apertures at the mounting stations; a plurality of pins for inserting through the aligned apertur

Abstract: A power shovel comprising a support unit: a stiffleg operatively connected to the support unit for pivotal movement about a stiffleg pivot axis, the stiffleg comprising a pair of transversely spaced, longitudinally disposed side beams each having an I-shaped cross-sectional configuration including upper and lower flange portions and an interconnecting web portion, a cross-piece section interconnecting the side beam sections and a web section interconnecting the web portions of the side beam sections; a handle operatively connected to the stiffleg for pivotal movement about a handle pivot axis; a dipper mounted on the handle; a crowd system operatively connected to the handle for crowding and retracting the dipper; and a hoist system for hoisting and lowering the dipper comprising at least one upper fluid actuated rod and cylinder assembly operatively connected at a lower end thereof to the stiffleg and operatively connected at an upper end thereof to the handle on one side of the handle pivot axis, at least o

Abstract: The present invention relates to a method for determining the locations of the two hydraulic jacks for controlling an assembly of two pivoted arms, the first arm, called boom or jib, pivoted on the frame of a public works machine, such as a loader or a hydraulic shovel, and the second arm, called balance beam, pivoted on the first arm, while a bucket, adapted to rest on the ground during loading, is coupled to said balance beam, each of said two jacks is coupled between the frame and the balance beam, at least one of the axes of coupling of one of the jacks being separate from the axis of coupling of the other jack on the same element--frame or balance beam--and the instantaneous centers of rotation of the bucket, corresponding respectively to the functioning of each of the control jacks when the bucket is near the ground, are chosen to be on the longitudinal axis of the boom, wherein the first instantaneous center of rotation is chosen to be near the ground, the second instantaneous center of rotation is cho

Abstract: A boom lifting system for a crane of the type having an upright mast and a boom hinged to the mast. The system has a brace extending between the mast and the boom. The brace is pivotally connected to both the mast and the boom and has a hinge dividing it into a short section, connected to the boom, and a long section, connected to the mast. A hydraulic cylinder is pivotally connected to both the boom and the short brace section. Actuation of the cylinder straightens or bends the brace to respectively lift or lower the boom relative to the mast.

Abstract: A backhoe boom is pivotally connected to a swing frame for vertical movement relative thereto. A power extendable and retractable linkage is connected between the swing frame and the boom and includes a hydraulic actuator having one end pivotally connected to the boom and having its other end pivotally connected to respective first ends of a pair of links having respective second ends respectively pivotally connected to the boom and to the swing frame. The links make it possible for the actuator to position the boom in a raised transport position wherein a connection of an outer end of the boom with a dipperstick is located rearwardly of a transverse vertical plane extending through a connection of an inner end of the boom with the swing frame.

Abstract: A valve block for hydraulic excavators having at least two sets of valves which are each coupled to their pump. The valves are of the type which, in the unactuated state, allows the passage of pressure medium. The hydraulic devices for executing working movements of the excavator are each coupled to their valve in each set. The valves in the one set are coupled in series, counted from the pump in the sequence the valve which is coupled to the hydraulic device for the first working movement of the excavator, the valve which is coupled to the hydraulic device for the second working movement of the excavator, and the valve which is coupled to the hydraulic device for the third working movement of the excavator.

Abstract: As the backhoe boom 19 swings into a swing stop, hydraulic fluid is trapped in the head end 28 of the swing side cylinder 24. This trapped fluid is discharged through a cylinder relief valve, thus absorbing the boom kinetic energy and providing a smooth deceleration of the boom. Fluid discharged from the relief valve 47 is routed to the rod end of the swing cylinder and the head end of the opposite cylinder. Because of the swing linkage geometry, the cylinder rod 30 of the other cylinder had passed over the pivot axis about which the backhoe boom was swinging and thus the piston 29 of the other cylinder was caused to move in the same direction as the swing side piston 29. The movement of this piston can be utilized to provide additional deceleration torque as long as no voiding is permitted to occur in the head end of this other cylinder. Voiding only occurs when the backhoe swing control lever 38 is released prior to the backhoe boom reaching the swing stop.

Abstract: A large mobile self-propelled excavator machine comprises an upper section on which a plurality of movable components, such as a boom, stick, and shovel, are mounted. A plurality of self-contained independently operable electrohydraulic power units are provided, one for each movable component, and each power unit comprises a housing, a pair of hydraulic rams mounted on the housing, means for pivotally connecting the housing and the ram piston rods to their associated components, a fluid reservoir in the housing, a reversible main pump in the reservoir for supplying the rams, auxiliary pumps on the housing, an electric motor on the housing for driving the pumps, and solenoid valve control means on the main pump. Each power unit is supplied with electric power for its electric motor by a cable from a generator on the upper section of the excavator machine.

Abstract: A lifting machine boom having two side walls maintained in spaced relationship to each other by a bottom wall and a top wall and a median reinforcing member dividing the interior of the boom into the first and second longitudinally extending chambers. One or more rigid pipes are attached to the median wall and run longitudinally of the boom from locations adjacent the ends. These pipes conduct pressurized fluid to and from one or more actuators carried by or associated with the boom. One said actuator is disposed in the second chamber.

Abstract: A loader comprises a bucket at the end of a dipper arm swinging from a cross-member on an upstanding yoke. The dipper arm swings between the uprights to the yoke for the bucket to pick up material on one side and deposit it on the other side. A winch actuates the bucket to dig and lift on the one side and a cam causes the bucket to turn upside down on the other side to deposit its load. The yoke can lean to the one side to extend the reach of the dipper arm and can slew about a vertical axis. The yoke can center itself when the dipper arm swings to the other side. For travelling the whole assembly can fold into a compact bundle.

Abstract: A shovel linkage for a hydraulic excavator includes boom rails having pivot means in one end for pivotal connection to an excavator and cross tubes extending between the rails near the pivot means and having pivot joints provided thereon for connection of actuating cylinders for the linkage in line with the cross tube and close to the pivot means whereby forces imparted to the linkage by the actuating cylinders will be directly through the center of the cross tube and very near the boom rail pivot means, minimizing bending moments in the linkage.The pivot joint includes a flat tab member provided on the cross tube and projecting outwardly along a diameter thereof, and a pin and ball connecting the bifurcated end of a hydraulic cylinder to the tab for limited rotation thereof. The pin is disposed substantially normal to the plane of the boom rails for unimpeded insertion and removal thereof.

Abstract: A releasable lock for locking a boom that is pivoted on a horizontal pivot axis on a frame disclosed herein. The releasable lock includes a pin or first member on the frame and a second member pivotally supported on the boom about a common pivot axis with one end of a unit fluid ram that has its opposite end connected to a material handling unit which is pivoted on the outer end of the boom. A releasable linkage includes linkage between the unit fluid ram and the second member with the linkage having a portion pivotally supported on the boom and arranged so that pivotal movement of the unit fluid ram away from the boom during actuation thereof will automatically release the lock.

Abstract: A work vehicle having a work arm assembly mounted for horizontal oscillation on a swivel platform. The arm assembly and the swivel platform are actuated by separate hydraulic actuators. The two actuators are connected in parallel with one another to a control valve via a circuit selection valve. The arrangement enables the swivel platform and the arm assembly to move in the same direction by operating the control valve.

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.