Abstract: A mobile lifting apparatus having an extendable boom assembly supported by a plurality of hydraulic cylinders extending upwardly from a wheeled chassis, and further having a fork attachment coupled to the extendable boom assembly. The fork attachment is configured to engage palletized loads and permits such loads to be raised and transported upon extension of the hydraulic cylinders. The fork attachment includes a buttress assembly that remains relatively stationary as the boom assembly is horizontally extended and retracted. The fork assembly further includes a pair of forks that are pivotal relative to the buttress assembly around a generally horizontal axis. The forks are coupled to the horizontally extendable portion of the boom assembly so that extension and retraction of the boom pivots the forks to change the angular orientation of the forks relative to horizontal. Such angular movement of the forks facilitates engagement and disengagement of the forks with the palletized load.

Abstract: A suspension arrangement for a heavy crawler vehicle having plural supporting rollers which are constructed and mounted on elastomeric pad devices such that the overall loading characteristic of the pads is non-linear and terminates in a bulk modulus compression range. The roller assemblies and pad devices are disposed in cavities in free sliding contact with the cavity walls. The rollers and elastomeric pad devices are so constructed as to facilitate relative vertical movement of the rollers under load along the sideframe to enable the vehicle to operate on uneven surfaces with superior load distribution between the totality of load-supporting rollers. The present invention also includes a crawler vehicle having tracks mounted for rolling action in either parallel or converging planes, depending on the contour of the road surface. The present invention also contemplates roller units mounted for lateral rocking movement, and also four roller units.

Abstract: A windlock for selectively preventing relative pivotal movement between a mobile platform and a horizontal interconnecting stinger at the base of an elevated crane. The stinger is normally interconnected to one load platform for relative pivotal movement about the stinger central axis. Outer horizontal surfaces on the stinger structure are longitudinally movable relative to the platform to a position between adjustable screws which engage them to lock the stinger against rotational movement. This locking arrangement applies the heavy weight of a remote counterweight unit to assist in preventing lateral tipping of the load platform on which the elevated boom is supported. Outboard jacks on the platform further stabilize it against lateral tipping movements.

Abstract: A large gantry for straddling and handling a heavy load comprises a pair of vertical support assemblies which support a horizontal load-bearing gantry beam. Each support assembly comprises three vertically disposed independently extendable/retractable hydraulic rams. A tiltable self-leveling sole plate is located between the upper ends of the three rams in each support assembly and the underside of an end of the gantry beam. A control system which includes selectively operable panel-mounted joy-stick actuated control switches and control valves effects operation of the rams in unison to raise and lower the gantry beam and also effects independent individual operation of any ram to level the beam if necessary. The arrangement increases the stability, the load-handling capacity and the operational safety of the gantry.

Abstract: A counterbalanced crane structure having an upright boom and diverging staymast mounted to a ground supported mobile crane base. An independent mobile counterweight unit has a vertical counterweight strut connected to the outer end of the staymast. The counterweight unit is interconnected with the crane base by an elongated horizontal stinger assembly. The counterweight unit is powered to move in an arc, the center of which is determined by the crane base. Turning motion is transmitted from the moving counterweight unit to the main boom and staymast by the stinger. Movable connections on the stinger permit pivotal movement of the counterweight unit about an axis that is substantially radial with the center turning axis of the mainboom and staymast and another pivot axis that is transverse to the radial axis. Limited movement of the counterweight unit toward or away from the crane base is permitted to eliminate direct transfer of tension and compressive stresses through the stinger.