Dual key locks having improved precision and versatility
OwnerJames M. Milesinventor
Life of this patent
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Abstract
The lock configuration described in the parent application enables a dual key lock to operate efficiently, accurately and conveniently with a single stack of tumblers. Also, the individual tumblers of the invention are typically receivable in the lock in a plurality of alternative orientations in which their gates assume different functions, facilitating key changes. The present application discloses means for further improving the precision of gate positioning in such locks, and remarkably simple and economical means for adapting such locks for either right- or left-hand installation.
Claims26
A lock which includes a housing having two end walls, bolt means, means for moving the bolt means along a bolt axis between locking and releasing positions, fence means coupled to the bolt means, at least one set of flat tumblers mounted in the housing for independent movement transversely of the bolt axis, at least one gated blocking edge on each tumbler for cooperation with the fence means to normally block the bolt means from movement toward releasing position, and key receiving means for controlling said tumbler movement to align the gates and unblock the bolt means;
- said lock being further characterized in that:
- each tumbler includes a second gated blocking edge facing oppositely to the first said edge,
- said bolt moving means include means operable alternatively for moving the bolt means in one direction for bolt projection at one housing end wall for right-hand installation, and for moving the bolt means in the other direction for bolt projection at the other end wall for left-hand installation,
- said fence means cooperating with one set of blocking edges for controlling bolt operation in one direction and cooperating with the other set of blocking edges for controlling bolt operation in the other direction.
A dual key lock comprising
- an elongated housing with apertures in its opposite end walls on a housing axis,
- an elongated bolt carrying two longitudinally spaced fences and having a head at each end adapted for projection through the respective end wall apertures,
- a stack of flat elongated tumblers mounted in the housing in defined longitudinal position and generally parallel to the axis for lateral movement under key control, each tumbler having two pairs of oppositely facing transverse gated blocking edges adapted for cooperating with the respective fences,
- two key nose cores normally journaled in the housing on respective key axes which correspond to the respective pairs of gated blocking edges,
- and bolt driving means for driving the bolt alternatively between projected and retracted relation to a selected one of the housing end walls in response to rotation of a key in a nose core on a corresponding key axis.
A dual-key lock comprising
- bolt means movable along a bolt axis between a locking position and a releasing position and including first and second fence means mutually spaced longitudinally of the bolt axis and coupled to the bolt,
- a plurality of flat elongated tumblers mounted generally parallel to the bolt axis in defined longitudinal position for lateral movement under key control, each tumbler including two transverse gated blocking edges in positions to cooperate with the respective fence means no normally block the bolt means from said releasing position,
- first and second key noses laterally offset from the tumblers and approximately aligned with the respective blocking edges,
- each tumbler having two laterally facing driving edges associated with the respective blocking edges and engageable by keys in the respective key noses to laterally position the tumblers to unblock the bolt means,
- at least one of said driving edges being curved convexly about a point adjacent the associated blocking edge.
A set of flat, elongated tumblers adapted to be mounted in a lock, each tumbler having a longitudinal axis and including:
- a guide slot transverse of the axis for slidingly receiving a fixed guide member,
- and structure forming two transverse, like-facing blocking edges spaced on opposite sides of the guide slot and having respective gate recesses for cooperating with fence means coupled to a lock bolt,
- each tumbler having two laterally facing driving edges engageable by keys in respective key noses to laterally position the tumblers to unblock the bolt means at the respective blocking edges,
- at least one of said driving edges being curved convexly about a point adjacent the associated blocking edge.
Cover structure for a lock case that includes an effectively unitary base and two side walls, comprising:
- an inner plate and an outer plate adapted to be superposed one upon the other with at least partial overlap to form a cover extending between the case side walls with one edge of each plate normally substantially abutting the inner face of an associated case side wall,
- coupling means on each said plate edge and on the associated side wall for confining said plate edge to a predetermined level on the side wall, each coupling means being engageable and releasable by virtue of respective movements of the associated plate substantially in its own plane toward and away from the associated side wall,
- and releasable locking means for coupling the plates together in said normal positions to lock each of them against movement away from the associated case side wall.
A set of flat tumblers of similar shape adapted to be mounted in a lock for relative sliding movement under key control for operation of the lock, further characterized in that
- each tumbler comprises sheet material and has two opposite edges,
- said tumblers have adjacent each of said edges a relatively narrow area in which the tumbler thickness is increased by folding of the material,
- and said areas of increased thickness are sufficiently wide to provide overlap with corresponding areas of adjacent tumblers in all operating positions of the tumblers in the lock.
Dependencies are inferred from the claim text.