Patent ID: 7454934

Claim:
A resettable tumbler lock comprising: a lock housing; a first sleeve mounted coaxially and rotatably in said lock housing and formed with a plurality of tumbler bores, each having a longitudinal axis and a non-circular cross-section perpendicular to said longitudinal axis; a cylindrical latch-connecting part mounted coaxially and rotatably in said lock housing and in end-to-end contact with said first sleeve, said latch-connecting part being formed with a plurality of circumferentially disposed tumbler holes and a plurality of circumferentially disposed blind holes that are angularly displaced with said tumbler holes; and a plurality of spring-biased tumbler units, each of which is disposed movably in a respective one of said tumbler bores, a respective one of said tumbler holes, and a respective one of said blind holes; wherein said first sleeve is operable to rotate relative to said latch-connecting part between a first angular position, in which said tumbler bores in said first sleeve are aligned axially and respectively with said tumbler holes in said latch-connecting part, and a second angular position, in which said tumbler bores in said first sleeve are aligned axially and respectively with said blind holes in said latch-connecting part; wherein each of said tumbler bores in said first sleeve has an axial projection that coincides with that of the axially aligned one of said tumbler holes in said latch-connecting part when said first sleeve is disposed at said first angular position, and that coincides with that of the axially aligned one of said blind holes in said latch-connecting part when said first sleeve is disposed at said second angular position; wherein at least one of said tumbler bores in said first sleeve is aligned axially with one of said tumbler holes in said latch-connecting part when said first sleeve is rotated relative to said latch-connecting part to a predetermined position between said first and second angular positions; and wherein the axial projection of said one of said tumbler bores in said first sleeve does not coincide with that of the aligned one of said tumbler holes in said latch-connecting part when said first sleeve is disposed at the predetermined position between said first and second angular positions so as to prevent deadlock from occurring on said resettable tumbler lock.