Gripping and cutting apparatus

摘要

Apparatus (10) having special application for gripping and cutting tree limbs around utility lines includes a tubular insert (18) slideably received in the free end of a tubular boom (12). A plate (28) is pivoted about a first pivot axis relative to the insert (18) by a linearly extendable actuator (36) mounted within the insert (18) and mounts a first rotary actuator (38). A second rotary actuator (58) is mounted to a U-shaped mount (48) which is pivoted about a second pivot axis to the first rotary actuator (38) and rotates a working head (96) 360° about a third pivot axis. Gripping arms (78) are fixed to shafts (74) rotatably mounted in the working head (96) about axes perpendicular to the third axis, with the shafts (74) being rotated by a single linearly extendable actuator (82) extending between crank arms (80) fixed to the shafts (74). The crank arms (80) abut with an abutment (84) to prevent only one set of gripping arms (78) from moving. An untethered remote control unit (112) is provided to prevent the creation of an electrical path to ground through the operator. A solar and battery-powered transmitter (144) mounted on the head (96) sends an electromagnetic signal to prevent actuation of the valves (101-103) controlling the operation of the boom assembly (14) when the saw bar (88) is not in its home position.