By means of counterweight balanced load carrier

摘要

The disclosure relates to a counter-balanced load carrier comprising a multi-stage telescopic arm (10). One stage (24) adjacent one end of the arm is mounted for rotation about a horizontal axis (29) in a carrier (17, 21) mounted for rotation by a vertical axis (20) on a mobile base (11). The adjacent end stage (23) of the arm carries a counterweight and the end stage (28) at the other end of the arm carries a support (32) for a TV or video camera. Th respective stages of the arm are interconnected by a cable or like mechanism to extend and retract together maintaining a fixed ratio between the radius of the payload support and the horizontal axis and the counterweight and the horizontal axis so that the arm remains counter-balanced throughout its range of extension and retraction. The cable mechanism also acts on the camera support on said end section of the arm to maintain the support horizontal throughout the range of tilting of the arm. An additional counterbalancing force can be applied at control point (39) on end stage (23) the control point being constrained to move in a vertical guideway (38) located on a horizontally moveable carriage (36) to follow the vertical/horizontal movement of the end stage of the arm.