Key changeable lock

In a changeable key lock having a bolt, a plurality of gated tumbler levers and means for operating the bolt only when the tumbler levers are placed in predeterminable positions by manipulation of a selectable key in the lock, the improvement comprising the provision of:

• pivot means on one or more of said levers for providing a plurality of individually selectable pivots about which the associated lever may pivot whereby the pivotal axis of each such lever may be varied to provide for different combinations of lever movements required to open the lock;
• and
• releasable fulcrum means for engaging with said lever pivots to restrict each levers movement about a selectable one of said pivots when engaged therewith and being releasable therefrom to allow for the selection of another of said pivots to be engaged thereby;
• wherein:
• said bolt is provided with forward and rearward latch plates;
• said gated tumbler levers are provided in a first set having gates alignable to said forward latch plate and a second set having gates alignable to said rearward latch plate whereby said levers must be operated by two changeable keys concurrently to open said lock;
• and
• said fulcrum means includes a fulcrum member and means for mounting said member for releasing and re-engaging lever pivots of both of said sets of levers on operation of said fulcrum means.

In a changeable key lock having a bolt, a plurality of gated tumbler levers and means for operating the bolt only when the tumbler levers are placed in predeterminable positions by manipulation of a selectable key in the lock, said bolt being provided with forward and rearward latch plates;

• the improvement comprising the provision of:
• pivot means on one or more of said levers for providing a plurality of individually selectable pivots about which the associated lever may pivot whereby the pivotal axis of each such lever may be varied to provide for different combinations of lever movements required to open the lock;
• and
• releasable fulcrum means for engaging with said lever pivots to restrict each levers movement about a selectable one of said pivots when engaged therewith and being releasable therefrom to allow for the selection of another of said pivots to be engaged thereby, wherein:
• said gated tumbler levers are provided in a first set having gates alignable to said forward latch plate and a second set having gates alignable to said rearward latch plate whereby said levers must be operated by two changeable keys concurrently to open said lock;
• said levers and said pivot means for said first and second set of levers are provided to allow for an alignment of selected pivots of different ones of said levers in a linear array to be engaged by said fulcrum means;
• and said pivot means comprise a fulcrum member and means for rotatably mounting said member in said lock for releasing and re-engaging said pivot means through rotation of said member about a fixed axis.

In a changeable key lock having a bolt, a plurality of gated tumbler levers and means for operating the bolt only when the tumbler levers are placed in predeterminable positions by manipulation of a selectable key in the lock, said bolt being provided with forward and rearward latch plates;

• the improvement comprising the provision of:
• pivot means on one or more of said levers for providing a plurality of individually selectable pivots about which the associated lever may pivot whereby the pivotal axis of each such lever may be varied to provide for different combinations of lever movements required to open the lock;
• and
• releasable fulcrum for engaging with said lever pivots to restrict each levers movement about a selectable one of said pivots when engaged therewith and being releasable therefrom to allow for the selection of another of said pivots to be engaged thereby, wherein:
• said gated tumbler levers are provided in a first set having gates alignable to said forward latch plate and a second set having gates alignable to said rearward latch plate whereby said levers must be operated by two changeable keys concurrently to open said lock;
• said levers and said pivot means for said first and second set of levers are provided to allow for an alignment of selected pivots of different ones of said levers in a linear array to be engaged by said fulcrum means;
• said pivot means comprises a plurality of pivots formed in an arcuate slot;
• and
• said fulcrum means comprises a fulcrum member extending through said slot and having a rib engaging one of said pivots and means for rotatably mounting said member in said lock for releasing and re-engaging pivots of said levers on rotation of said member.

A double key changeable safety deposit lock comprising:

• a moveable bolt and an associated bolt plate means provided with forward and rearward latch plates and including cam surfaces to be engaged and moved between open and closed positions by turning renter and guard keys in said lock, a first plurality of gated tumbler guard key levers to be engaged by said guard key and having gates alignable to one of said plates and a second plurality of gated renter key levers to be engaged by said renter key and having gates alignable to the other one of said latch plates, said levers being moved to align their respective gates to receive the respective latch plates on said bolt plate to allow opening said lock only when both said keys are operated;
• pivot means on each lever for providing a plurality of individually selectable pivots whereby the pivotal axis of each lever may be varied to provide for different combinations of lever movement required by an associated key to align the associated gates;
• and
• releasable pivot selecting means for normally engaging certain ones of said pivots, of levers of both said first and second plurality of levers and being releasable to allow movement of said levers to a different pivot position determined by an associated key and for re-engaging the thus aligned pivots to allow changing the combination thereof for either or both of said guard and renter keys.

A double key changeable safety deposit lock including a moveable bolt and an associated bolt plate including cam surfaces to be engaged and moved between open and closed positions by turning renter and guard keys in said lock, a plurality of gated tumbler guard key levers to be engaged by said guard key, said levers being moved to align their respective gates to receive latch members on said bolt plate to allow opening said lock by said keys, the improvement comprising the provision of:

• pivot means on each lever for providing a plurality of individually selectable pivots whereby the pivotal axis of each lever may be varied to provide for different combinations of lever movement required by an associated key to align the associated gates;
• and
• releasable pivot selecting means for normally engaging certain ones of said pivots, and being releasable to allow movement of said levers to a different pivot position determined by an associated key and for re-engaging the thus aligned pivots and
• wherein said releasable pivot selecting means comprises a fulcrum member and means for rotatably mounting said member in said lock for releasing and re-engaging said pivot means through rotation of said member about a fixed axis.