Lock having a helical keyway and accompanying key and methods therefor
OwnerChien-Kuo Liuinventor
Life of this patent
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Abstract
The present application advantageously provides at least one keyway in a lock core that poses tremendous difficulty for a lock breaker by not allowing the lock breaker to see all of the pin tumblers in the keyway. The keyway according to a preferred embodiment of the present application comprises two helical keyways oppositely extending along a longitudinal axis of the lock core and formed of rectangular cross section. The present application further comprises an accompanying helical key having at least one helical key blade for fitting into the keyway having a corresponding helical shape to turn the core and open the lock.
Claims26
A key comprising:
- a key head;
- a shank connected to said key head at a first end thereof and provided with a protrusion at a second end thereof, said shank having a pair of grooves extending oppositely laterally along a lengthwise direction thereof;
- a driving head movably mounted on said shank, said driving head having an inner opening in the center thereof and a cavity in one side thereof, the inner opening provided with a pair of protrusions oppositely located in an inner surface thereof;
- and
- a key blade portion rotatably movably mounted on said shank, said key blade portion comprising a blade head having an inner opening, a bearing assembly disposed between the blade head and the cavity of the driving head, and at least one helical key blade extending from a periphery of the inner opening of said blade head.
The lock and key combination comprising:
- a shell having a cylindrical opening;
- a lock core rotatably mounted in said opening of said shell and having at least two helical keyways and at least one pin tumbler bore situated inside the lock core for receiving a pin tumbler;
- and
- a key having at least two helical key blades corresponding to said at least two keyways of said lock core, wherein said key further comprising:
- a key head;
- a shank connected to the key head, said shank having a pair of grooves oppositely laterally extending along a lengthwise direction thereof;
- a driver head having an inner opening in the center thereof and a cavity in one side thereof, said inner opening provided with a pair of protrusions oppositely located in an inner surface thereof;
- and
- a key blade portion received in the cavity of the driver head, said key blade portion comprising a blade head having an inner opening, a bearing assembly disposed between the blade head and the cavity of the driver head, and at least two helical key blades extending from a periphery of the inner opening of said blade head.
Dependencies are inferred from the claim text.