Counterweight hoisting mechanism

Abstract

The invention provides a self-mounting counterweight device which is mounted to one end of the chassis frame of the vehicle. The counterweight is U-shaped having two vertical sides and an outward wall defining an internal enclosure. The counterweight includes a rod mounted to the top of the counterweight for suspending it from a boom and includes lateral threaded bolts to releasably mount the counterweight to blocks on the chassis frame. The lifting boom has an inward end journalled to the frame and an outward end with tackle for releasably connecting the boom outward end to the counterweight suspending rod. A hydraulic cylinder provides mechanical lift with an inward end journalled to the frame and an outward end pivotally connected to the boom. The combination of the boom and lift provides a scissor-like lever for selectively raising and lowering the counterweight between a lowered and mounted position. In the lowered position, the boom and counterweight are extended outwardly to hoist the counterweight on an adjacent ground surface. In the mounted position, the boom and hydraulic cylinder fold or nest within the internal enclosure of the U-shaped counterweight. In the mounted position therefore, the hydraulic cylinder and boom are axially bounded by the vehicle frame and counterweight rear wall and laterally bounded by the counterweight side wall. Damage to the boom and hydraulic cylinder with attached hydraulic hoses etc. is minimized by surrounding the relatively delicate bearings and shaft of the boom, hydraulic cylinder and hose fittings within a thick-walled steel plate enclosure of the U-shaped counterweight and chassis frame.

Dependencies are inferred from the claim text.