Patent ID: 8826709

Claim:
A swing bolt lock comprising a swing bolt mounted in a housing adapted to be mounted to a door having a spindle hole defined therethrough, the swing bolt being pivotable between a locking and an unlocking position, a blocker movably mounted in said housing towards and away from the swing bolt for selectively blocking or allowing rotation of the swing bolt during normal operation, and a relocking mechanism for automatically locking the swing bolt in a secure locked state when the lock is subject to a physical attack, the relocking mechanism comprising a first member connected in force transmission relationship to the housing such that externally-applied forces against the housing through the spindle hole of the door are transmitted to the first member, and a second member having an abutting surface for engagement with the swing bolt, the abutting surface of the second member physically blocking the swing bolt from moving to the unlocking position when the first member is moved from an initial default position to an operational position under the externally-applied forces wherein prior to a physical attack, the second member is held in a non-operational retracted position by the first member, and wherein the first member comprises a breakaway member mounted to an inner face of the housing, the breakaway member having a free distal end portion which extends in front of the second member when the breakaway member assumes its initial default position before the physical attack.