US 4,578,969 A · Tumbler lock having peripheral key

Abstract

A peripheral key for a tumbler lock, the key being transversely curved concentrically with the axis of the lock, and having an L-shaped groove to pass a sentry lug on a lock. The L-shaped groove has a longitudinal leg opening longitudinally at the free end of the lock, and a lateral leg communicating with the inboard end of the longitudinal leg and opening laterally to enable the sentry lug to pass along and out of the L-shaped groove to free the key for further operative movement. A tumbler lock having code discs and actuating discs, and a pusher plate having a lost-motion connection with a mounting plug to pick up the plug after predetermined movement of a curved peripheral key. A key as first described above, together with a lock having a sentry lug for accommodating insertion of the key into the lock. A lock and peripheral curved key wherein the key has concentric inner and outer surfaces engaging mating curved surfaces on a lock housing and central internal components to maintain the key in a longitudinal position while being used.

Claims10

Dependent claims

A peripheral key for a tumbler lock comprising an elongated body member having curved portions for peripheral contact with curved portions of the lock,

said elongated body including a handle portion and an operating portion connected together by a dog leg or stepped portion,
said operating portion having an outer end remote from said dog leg and an inner end terminating at said dog leg,
said operating portion having concentric inner and outer curved faces,
said inner face having a longitudinally extending groove formed therein having an open end at the outer end of said operating portion for entry of a sentry lug on the lock and passage of said lug, relatively speaking, along said groove,
said groove being defined in part by two side walls and a bottom wall,
said inner curved face being formed, at the end of the groove closest the dog leg, with a transverse circumferentially extending arcuate groove communicating with the just mentioned end said lug passage groove,
said transverse groove having a blind end located at the inner end of said lug passage groove and an open end remote therefrom to permit escape of the sentry lug from said key retaining groove,
said blind end of said transverse groove being defined by the side wall of said longitudinal groove that is remote from the open end of said key retaining groove.

5 more elements

Dependencies are inferred from the claim text.

Tumbler lock having peripheral key

Life of this patent

Tumbler lock having peripheral key

Life of this patent

Abstract

Claims10