Plunger lock for manual dispensing pump

Abstract

The plunger of the pump has an axial lock by which the plunger can be locked down in its fully depressed position during periods of non-use and a rotary lock for preventing inadvertent rotation of the plunger out of its locked down mode. The rotary lock includes a pair of yieldably spreadable arms which circle the collar of the pump and latch against one another in overlapping, embracing relationship so that the lock is held tightly on the collar against rotation relative thereto. A locking bar integral with the arms and of essentially rigid construction projects up out of the plane of curvature of the arms and has a saddle-like notch at its uppermost tip which complementally receives a portion of the spout associated with the discharge head of the plunger, thereby rendering the plunger rotatively immobile relative to the collar. If desired, hinge lines which permit the arms to flex toward and away from one another during installation and removal of the rotary lock from the pump may be intentionally designed to be in a sufficiently weakened condition as to permit at least one of the arms to be torn free from the remainder of the lock in order to release the latter from the pump. Mating teeth of optional configurations may be provided on the interior portions of the arms and the exterior of the pump collar to promote tight retention of the lock on the collar.