Load sensor for controlling the tightening of pieces joined by a bolt

摘要

The force sensor (2) allows monitoring of the tightening of an assembly of components (3,5) which are held together by a threaded shaft (1) with a nut (7) screwed on to the projected end. The sensor is in the shape of a washer (4) which fits between the uppermost component (3) and the clamp nut so that it is compressed by the action of tightening the nut. The sensors consists of two half shells (4a, 4b) with strain gauges (6) mounted in the space defined between these two halves. In cross-section each of the half shells is of L-shape, with the two L-shapes defined a box between them. The strain gauges are mounted on the vertical wall on one element with connection wires leading out through a sleeve (8) in the outer element.