Double changeable key lock for safe deposit boxes and the like

A multiple key lock for safe deposit boxes and the like comprising a lock housing, a bolt slidably supported in said housing for movement between a projected locking position and a retracted unlocking position, a plurality of platelike gate members releasably carried by said bolt to prevent movement of the bolt from said locking position toward unlocking position until a plurality of mating tumbler levers operated by a renter's key and a guard key are alined in selected relation to each of the gate members, the improvement permitting changing of both the renter's key and the guard key for opening the lock comprising a first set of plurality of renter's key tumbler levers pivotally mounted adjacent one end on a common pivot axis and having first key follower surfaces on each tumbler lever thereof to be engaged by a renter's key insertable in said lock at a renter's key station, the lock having renter's key-receiving means spaced laterally of said common pivot axis and located adjacent said key follower surfaces, and a second set of a plurality of guard key tumbler levers pivotally mounted on said common pivot axis and having second key follower surfaces on each said guard key tumbler lever to be engaged by a guard key insertable in said lock at a guard key station spaced from said renter's key station, the lock having guard key-receiving means spaced laterally of said common pivot axis oppositely disposed relative to the renter's key receiving means, whereby adjustment of the gate members carried by said bolt relative to each of the two sets of tumbler levers permits changing of the customer and guard keys, said bolt including gate locator means having a projection to be interfitted in holding relation with an edge of each of said gate members and movable between a gate-holding and gate-releasing position, and a gate release cam accessible from externally of the lock housing when the bolt is in a preselected intermediate position to be manipulated for shifting said gate locator means between gate-holding and gate-releasing positions.

A lock requiring two different keys for operation of the lock to unlocking position, comprising a lock housing, a slide bolt mounted in the housing for sliding movement between projected and retracted positions, a plurality of gate members each having a gating recess, means mounting said gate members in said housing for movement with said slide bolt, a first set of a plurality of tumbler levers to be positioned by a first key, means for mounting said tumbler levers of said first set in said housing positioning them normally in interfering relation to a first set of said gate members and mounting said tumbler levers for movement under operation of said first key in said lock to a non-interfering position, a second set of a plurality of tumbler levers to be positioned by a second key, means for mounting the tumbler levers of said second set in said housing positioning them normally in interfering relation to a second set of said gate members and mounting them for movement under operation of said second key in said lock to a non-interfering position, said tumbler levers having portions disposed to engage said gate members and prevent movement of said slide bolt to unlocking position until both said first and second keys have been inserted in said lock and are positioned to concurrently hold said two sets of tumbler levers in said non-interfering position relative to said two sets of gate means whereby the gate members are then released to permit retraction of said bolt to unlocking position, said bolt including gate locator means having a projection to be interfitted in holding relation with an edge of each of said gate members and movable between a gate-holding and gate-releasing position, and a rotatable gate release cam carried by said bolt and intercoupled with said gate locator means for shifting the same between gate-holding and gate-releasing position, said gate release cam being alinable with an opening in said housing when said bolt is in a predetermined intermediate position between said projected and retracted positions for insertion of a tool to shift the gate release cam between positions disposing said gate locator means at gate-holding and gate release positions.

A multiple key lock for safe deposit boxes and the like comprising a lock housing, a bolt slidably supported in said housing for movement between a projected locking position and a retracted unlocking position, a plurality of platelike gate members releasably carried by said bolt to prevent movement of the bolt from said locking position toward unlocking position until a plurality of mating tumbler levers operated by a renter's key and a guard key are alined in selected relation to each of the gate members, the improvement permitting changing of both the renter's key and the guard key for opening the lock comprising a first set of a plurality of renter's key tumbler levers pivotally mounted adjacent one end on a common pivot axis and having first key follower surfaces on each tumbler lever thereof to be engaged by a renter's key insertable in said lock, the lock having renter's key-receiving means spaced laterally of said common pivot axis and located adjacent said key follower surfaces, and a second set of a plurality of guard key tumbler levers pivotally mounted on said common pivot axis and having second key follower surfaces on each said guard key tumbler lever to be engaged by a guard key insertable in said lock, the lock having guard key-receiving means spaced laterally of said common pivot axis oppositely disposed relative to the renter's key receiving means, whereby adjustment of the gate members carried by said bolt relative to each of the two sets of tumbler levers permits changing of the customer and guard keys, said bolt including gate locator means having a projection to be interfitted in holding relation with an edge of each of said gate members and movable between a gate-holding and gate-releasing position, and a rotatable gate release cam carried by said bolt and intercoupled with said bolt locator means for shifting the same between gate-holding and gate-releasing position, said gate release cam being alinable with an opening in said housing when said bolt is in a predetermined intermediate position between said projected and retracted positions for insertion of a tool to shift the gate release cam between positions disposing said gate locator means at gate-holding and gate release positions.