POSITIVE LOCK COUPLING

摘要

A first coupling member has a peripheral facing surface with a pair of annul ar raised locking tabs (76, 78), each of a different length and width. A second coupli ng member has a lock ring (40) longitudinally slidable thereon with a facing surface having a pair of annular slots (64, 66) sized to correspond to the respective annular tabs. A resilient annular spring (42) mounted within the lock ring urges it toward the first coupling member so th at the locking tabs engage their respective slots when the coupling is tightened to a predetermined extent during rotation in the locking direction to releasably and positively lock the coupling. An indicator strip (74) on the peripheral edge of the first coupling member is exposed before t he locking tabs and slots are engaged. Alignment between the respective locking tabs and slots allows longitudinal movement of the lock ring so that it covers the indicator stripe. One of the coupling members has a peripheral groove and two angularly spaced longitudinal keyways of differing widths which intersect the peripheral groove. The annular spring has an internal peripheral edge with a plurality of peripherally spaced spring tabs for holding it in the peripheral groove. A spring key on the internal peripheral edge of the annular spring has a width correspondingto the width of one of the keyways to rotationally position the annular spring with the coupling member. The annular wall of the lock ring has two angularly spaced keys of differing widths which correspond to the widths of the keyways and are received therein to angularly position the lock ring with the coupling member and the spring.