Patent GB-1139904-A (GB)
Title: Improvements in or relating to a push button combination locks
IPC: E05B37/16
Filed: 1966-02-23
Abstract: 1,139,904. Combination locks. J. SHIMOND. 23 Feb., 1966, No. 7980/66. Heading E2A. A combination lock of the push button type comprises a casing 83 having a front plate 96 and a rear plate 91, a lock bar 5 mounted by said casing for sliding movement between a locking position and an unlocking position and having a plurality of notches spaced along its length, a first handle member 113 projecting through the front plate, a second handle member 114 projecting through the rear plate, each of said handle members being operable independently of the other for sliding the said lock bar between its said locking and unlocking positions, a plurality of engaging rings 28, 34, 41 mounted for rotational movement into and out of engagement with said notches and operable to lock said lock bar in its locking position when any one of said engaging rings engages with its said notch, a first locking push button 93 projecting through the front plate, a second locking push button 92 projecting through the rear plate, each of said locking push buttons being operable independently of the other to cause said engaging rings to take up positions wherein a selected number 34, 41 of said engaging rings are in engagement with a corresponding number of the said notches and the remainder of the engaging rings 28 are out of engagement with the remainder of the notches whereby with the lock bar in its locking position the said selected number of the engaging rings lock the lock bar in that position, an unlocking push button 89 projecting through the rear plate and a further plurality of push buttons 100, 101, 102 projecting through the front plate, the said unlocking push button and a selected number 101, 102 of said further plurality of push buttons being operable independently to cause said selected number of rings to move in positions wherein they are out of engagement with said notches freeing said lock bar for movement out of its locking position by operation of either of said first and second handle members, in which the movement of the engaging rings to their unlocking disengaged positions is effected either by operation of the said unlocking push button or by a selected number of operations of the selected number of said further plurality of push buttons, and in which operation of the remainder 100 of said further plurality of push buttons when the lock bar is in its locked position causes the said remainder 28 of the engaging rings to take up positions in engagement with the said remainder of the notches to prevent unlocking of the lock bar. In the construction shown the engaging rings are all rotatably mounted on a shaft 1 and they are separated from each other by washers 20, 24; the bar 1 has a groove 6 in which the locking bar 5 is slidable, one end portion of the locking bar protruding through an aperture in an end wall of the casing 83 which contains the rings shaft. Each engaging ring has a notch which extends from a central hole in the ring which receives the shaft 1. There are seven rings 28 and each of these has its notch aligned with the locking bar when the locking bar is in the locking condition and these serve to prevent release of the bar if they are in error rotated out of the aligned position during the unlocking operation; there are two rings 34 and a single ring 41 which in the locking condition have their notches out of alignment with the bar so that they prevent movement of the bar. The locking bar is unlocked by bringing the notches in the rings 34 and 41 into alignment with the bar and this is 'done from the outside of the door by a single depression of the associated push button 101 for each of the rings 34 and by two depressions of the associated push button 102 for the ring 41 after which the bar can be moved to unlocking position by pivoting of the handle member 113. To place the bar in locking condition the handle member 113 is first pivoted to move the bar until a magnet 84 is in engagement with a 3 on the shaft 4 and then the push button 93 is depressed to cause a bar 68 to move the rings 34 and 41 back to their locking positions. If during the unlocking operation any of the rings has been placed in ah incorsect position, depression 'of 'the push button 93 'moves them back to "their normal positions via .the' bar 68 this' applies not'only to t"he" .rings 28' 'but .also. to. the :rings:34 and 41 since if the push buttons controlling the rings'. 34 are depressed twice instead of once the rings are moved too far so that the locking bar cannot be moved and similarly, if the push button -controlling/the ring 41 is only depressed once the ring: 41 is-not moved far enough to unlock the bar. From the inside of the door the rings are moved simultaneously to their unlocking positions by depression' of the push button 89 which moves 'the rings 34 and 41 via a bar 57 and these rings are restored to locking position by the push button 92 which moves the bar 68. When the rings have been moved to the unlocking positions by depression of the push button 89, the handle member 114 must be operated from inside the door to move the bar to unlocking position. The casing- is provided .with. a cover which normally covers .the .push. buttons 93, 100, 101 and 102 and the cover controls a switch so that when the cover is raised' the face of the casing containing these push buttons is illuminated.