Pivot angle adjusting means for the arm of a material handling device

Abstract

Pivot angle adjusting means for the arm of a material handling device such as industrial robots are disclosed. An arm connected to a rotary shaft via a mount is pivotably mounted to a support. A cylindrical vane chamber having a rotary vane therein is mounted to the support, wherein the rotary vane secured to the rotary shaft is pivoted by a fluid supplied to the cylindrical vane chamber. A stopper is mounted to the rotary shaft and its pivot angle is detected by a pair of sensors mounted to the support. A stop is mounted to the support and is movable at a certain distance in the direction of the movement of the stopper. The stop can be placed in the locus of the movement of the stopper so as to stop the stopper at a certain intermediate point within the pivot movement of the stopper in its clockwise and counterclockwise movements, thereby stopping the arm at the intermediate point. Further, a pair of stoppers may be mounted to the rotary shaft via a spur wheel at a certain angle and actuate the sensors, and another stopper may be mounted to the rotary shaft via another spur wheel and is stopped by the stop at the intermediate point.