Combination lock

Abstract

A combination lock of the exposed shackle type is disclosed. The shackle is held in its locked position by locking means that are released when a fence member is moved into gates located in the periphery of two tumbler wheels. The tumbler wheels are positioned for the gates to receive the fence by a dial and keyed shaft, after which the key is moved axially of the shaft out of driving connection with the tumbler wheels and into driving connection with the fence means. Rotation of the dial moves the fence means to release the shackle. The tumbler wheels have a rim and hub that are connected through a friction clutch type connection to allow the rim to be held while the hub is rotated. This allows the combination of the lock to be changed, when the lock is open, by actuating a lever mounted externally on the side of the lock housing that holds the fence means in engagement with the gates in the periphery of the tumbler wheels while the hubs are rotated by the dial. If the combination is forgotten, apparatus is provided to locate the rims in a predetermined position from which position a master combination can be used to open the lock. .Iadd.

The invention having been described, what is claimed is: 
     
       1. A combination lock comprising a shackle movable between a locked and an unlocked position;   locking means movable into and out of locking engagement with the shackle;   fence means for moving the locking means out of locking engagement with the shackle;   a plurality of tumbler wheels having peripheral gates to receive the fence means and permit the fence means to move the locking means out of locking engagement with the shackle;   a rotatable dial; and   means rotated by the dial and movable axially between a first position in driving engagement with the tumbler wheels for rotating the tumbler wheels to the desired position for the gates therein to receive the fence means, and a second position out of driving engagement with the tumbler wheels and in driving engagement with the fence means to move the fence means into the gates and move the locking means out of locking engagement with the shackle.   
     
     
       2. The lock of claim 1, further provided with means resiliently urging the tumbler wheel and fence driving means to the first position. 
     
     
       3. The lock of claim 1 in which each tumbler wheel comprises a hub, an outer rim mounted on the hub, and means for providing a frictional connection between the hub and rim that will slip when the rim is held against rotation and the hub is rotated. 
     
     
       4. The lock of claim 3, further provided with means to hold the fence means in engagement with the gates of the tumbler wheels to hold the rims stationary while the hub of the wheels are rotated to change the combination required to position the gates to receive the fence means. 
     
     
       5. The lock of claim 3, further provided with means for opening the lock when the combination is forgotten, including means for stopping the rotation of each of the rims of the tumbler wheels in a predetermined position to allow the tumbler wheels to be rotated from the predetermined position in accordance with a known master combination, to a position for their gates to receive the fence means and open the lock. 
     
     
       6. The lock of claim 5, further provided with second combination lock means for preventing the actuation of the lost combination rim positioning means. 
     
     
       7. The lock of claim 6 in which the second combination lock means includes a tumbler cylinder positioned for rotation on its longitudinal axis in an opening in a fixed body, said opening having an intersecting, parallel slot along one side, a lug attached to the cylinder that holds the cylinder from movement axially out of the opening except when the lug is in position to move through the slot, and means connecting the tumbler cylinder to the means for stopping the rims in a predetermined position to hold said means out of the rim stopping position until the lug is positioned to allow the cylinder to move axially of the opening. 
     
     
       8. The lock of claim 7 in which the second combination lock means includes a second tumbler cylinder located in a second hole in said body having a parallel, intersecting slot, and a lug on the second cylinder to hold the cylinder from moving axially except when aligned with said slot, and means connecting the second tumbler cylinder to the means for stopping the rims in a predetermined position to hold said means out of rim stopping position until the lugs on both the first and second cylinders are positioned to allow the cylinders to move axially of the openings in which they are located. 
     
     
       9. The lock of claim 1, further provided with a housing having one side that can be disconnected from the remainder of the housing to expose the portions of the lock inside the housing, means releasably holding said side to the housing, said means being located inside the housing and accessible through opening means in the housing, said holding means and opening means being positioned so the shackle is located between the opening means and the holding means when in its locked position and can be moved out of position between the holding means and the opening means only when the shackle is unlocked. 
     
     
       10. The lock of claim 1, further provided with a housing and in which the shackle is U-shaped having one leg that moves out of the housing when the shackle moves to its unlocked position, and in which said lock is further provided with means to resiliently urge the shackle to rotate around the longitudinal axis of the second leg a predetermined amount when the shackle moves to its unlocked position. 
     
     
       11. A combination lock comprising a shackle movable between a locked and an unlocked position;   locking means movable into and out of locking engagement with the shackle;   fence means for moving the locking means out of locking engagement with the shackle;   a plurality of tumbler wheels having peripheral gates to receive the fence means and permit the fence means to move the locking means out of locking engagement with the shackle; and   a shaft supporting the tumbler wheels for rotation, means supported by the shaft for rotating therewith to cause the fence means to move the locking means out of locking engagement with the shackle, dial means for rotating the shaft, and means movable between a first position providing a driving connection between the shaft and one of the tumbler wheels for rotation of the wheel with the shaft, and a second position providing a driving connection between the shaft and the fence actuating means for rotation of the fence actuating means with the shaft.   
     
     
       12. The lock of claim 11 in which the dial is movable axially of the shaft and means are provided connecting the dial to the movable means providing a driving connection alternatively between the shaft and the fence actuating means so that movement of the dial axially of the shaft moves the driving connection means between its first and second positions. 
     
     
       13. The lock of claim 12 in which one of said tumbler wheels and said fence actuating means have keyslots, and in which shaft has a keyway therein and said driving connection means comprises a key located in the shaft and movable axially of the shaft and the means connecting the key to the dial includes spring means for urging the key out of the slot into driving engagement with keyslots provided in said tumbler wheel and said fence actuating means. 
     
     
       14. The lock of claim 11 in which each tumbler wheel comprises a hub, an outer rim mounted on the hub, and means for providing a frictional connection between the hub and rim that will slip when the rim is held against rotation and the hub is rotated. 
     
     
       15. The lock of claim 14, further provided with means to hold the fence means in engagement with the gates of the tumbler wheels to hold the rims stationary while the hub of the wheels are rotated to change the combination required to position the gates to receive the fence means. 
     
     
       16. The lock of claim 14, further provided with means for opening the lock when the combination is forgotten, including means for stopping the rotation of each of the rims of the tumbler wheels in a predetermined position to allow the tumbler wheels to be rotated from the predetermined position in accordance with a known master combination, to a position for their gates to receive the fence means and open the lock. 
     
     
       17. The lock of claim 16, further provided with second combination lock means for preventing the actuation of the lost combination rim positioning means. 
     
     
       18. The lock of claim 17 in which the second combination lock means includes a tumbler cylinder positioned for rotation on its longitudinal axis in an opening in a fixed body, said opening having an intersecting, parallel slot along one side, a lug attached to the cylinder that holds the cylinder from movement axially out of the opening except when the lug is in position to move through the slot, and means connecting the tumbler cylinder to the means for stopping the rims in a predetermined position to hold said means out of the rim stopping position until the lug is positioned to allow the cylinder to move axially of the opening. 
     
     
       19. The lock of claim 18 in which the second combination lock means includes a second tumbler cylinder located in a second hold in said body having a parallel, intersecting slot, and a lug on the second cylinder to hold the cylinder from moving axially except when aligned with said slot, and means connecting the second tumbler cylinder to the means for stopping the rims in a predetermined position to hold said means out of rim stopping position until the lugs on both the first and second cylinders are positioned to allow the cylinders to move axially of the openings in which they are located. .Iadd. 20. A combination lock comprising a bolt movable between a locked position and an unlocked position, means for holding the bolt in its locked position, means for releasing the holding means to allow the bolt to be moved to its unlocked position including a plurality of tumblers mounted for rotation, dial means for rotating the tumblers to a preselected position in accordance with a selected combination to allow the holding means to be released, and means for opening the lock when the selected combination is forgotten including means movable into engagement with each tumbler as the tumbler is rotated by the dial means to indicate when the tumbler reaches a preselected position from which position each tumbler can be rotated by the dial means to another position in accordance with a master combination to open the lock. .Iaddend. .Iadd. 21. The lock of claim 20 further provided with means to change the selected combination including dial means for indicating the position to which each tumbler is positioned and means for changing the relative position of the dial means and the position of the tumblers when in position to allow the holding means to be released to change the combination for opening the lock. .Iaddend..Iadd. 22. The lock of claim 20 in which each tumbler comprises a hub and an outer rim mounted on the hub to grip the hub with sufficient force to provide a frictional connection between the two that will cause the rim and hub to rotate together when both are free to rotate and will slip when one is held against rotation and the other is rotated. .Iaddend. .Iadd. 23. The lock of claim 20 in which each tumbler has an opening and the means movable into engagement with each tumbler includes a member for moving into the opening to stop the rotation of the tumbler in said preselected position when the tumbler has been rotated to locate the opening in position to receive the member. .Iaddend.