Abstract: A trenching apparatus comprises a boom assembly having a lower end mounted on a support base and an upper end connected to a boom mounting bracket which is joined by a coupler to a digger arm operative to form a trench alongside the support base following a trench line. Linear actuators are carried by the boom mounting bracket, the coupler and the digger arm to manipulate the digger arm about an X axis, a Y axis and a Z axis which are mutually perpendicular. Other linear actuators vertically raise and lower the boom assembly, and pivot it in an arc-shaped path relative to the support base, in the course of a trenching operation.

Abstract: This invention relates to a motion multiplier for use with an extendible boom forklift vehicle wherein a light-duty fork carriage is linked to the motion multiplier attached to a heavy-duty fork carriage to allow motion of the light-duty forks to translate to a multiplication of motion of the heavy-duty forks. The motion multiplier is a cylinder, piston and rod assembly which, when utilized between a light-duty fork carriage and a heavy-duty fork carriage, allows for movement of a particular distance of the light forks to be translated into movement of twice that distance by the heavy forks. The motion multiplier allows for a heavy-duty fork carriage to be superimposed upon and operated by a light-duty fork carriage without any need for disconnecting and reconnecting hydraulic systems.

Abstract: An extendable boom fork lift vehicle is described wherein the boom and its actuator are positioned over the rear axle of the vehicle such that the weight of the frame between the front and rear axles and behind the rear axle may be reduced. A modified boom and jib are also described wherein the jib may be selectively fixed relative one telescoping member of the boom. A light-duty carriage is provided to operably engage and articulate a secondary heavy-duty carriage.

Abstract: An extendable boom fork lift vehicle is disclosed wherein the bottom and its actuator are positioned over the rear axle of the vehicle such that the weight of the frame between the front and rear axles and behind the rear axle may be reduced. A modified boom and jib are also described wherein the jib may be selectively fixed relative one telescoping member of the boom. A light-duty carriage is provided to operably engage and articulate a secondary heavy-duty carriage.

Abstract: In an earth scraper tractor a rigid side-tilt roll-over protection cab having the operator's seat secured to the cab rather than to the tractor frame is mounted on the tractor frame in a manner such that, in the event of roll-over, the mounting means plastically deforms without deformation of the cab, thereby absorbing impact energy, maintaining the integrity of the cab and preventing the cab from being torn loose from the cab. The mounting means includes a pair of transverse frame members secured to the tractor frame so as to extend outboard thereof and supporting the cab from below by pin connections which serve as part of the tilting mechanism. Also forming part of the mounting means is a deformable post member rigidly connected to the cab and pin-connected at its lower end to the tractor frame.

Abstract: A pivot pin or the like is retained in an aperture in a supporting structure by a removable locking element inserted by movement transverse to the axis of the pin into a position lying between one end of the pin and a fixed flange-like retaining element which is secured to the supporting structure adjacent the aperture. In the illustrated embodiments the end of the pin is partially cut away so as to form a notch for receiving the locking element.