GB1086481A - Push-button operated combination locks - Google Patents

Abstract

1,086,481. Combination locks. A. C. SANOWSKIS. Jan. 27, 1965 [Sept. 10, 1964], No. 3622/65. Heading E2A. A push button operated combination lock has a plurality of buttons 28 requiring the consecutive depression of a chosen sequence of some of all of the buttons to effect the change of said lock from an initial locking condition to an unlocking condition and includes a controlling device 114,-116 moved by said buttons and shiftable step-by-step in a first direction, to unlocking condition, to allow a spring biased means 96 to extend therethrough but only upon depression of the proper sequence of said button and wherein depression of said buttons in other but the predetermined sequence serves to prevent the movement of the controlling device towards said unlocking condition, and means both for withdrawing the spring biased means from the controlling device and for resetting the controlling device to the initial locking condition. In the construction shown the controlling device consists of two racks 114, 116 which are slidably mounted in a slot 52 of a body 24 which also carries the push buttons 28. Each push button can engage teeth 118 of the racks by means of an arm 48 of a spring 44 and each spring 44 and its associated push button is biased to the inoperative position by a spring 72 which surrounds a guide post 70 on a cover plate 26. Some of the teeth 118 of the racks have surfaces 124 which are inclined in one direction, some have surfaces 125 which are inclined in the opposite direction and some have both surfaces; when the chosen buttons are consecutively depressed in the proper sequence each arm 48 engages one of the surfaces 124 of both racks so that the racks are moved together one step at a time. If an incorrect button is depressed or the chosen buttons are depressed in the wrong sequence the arm 48 of the incorrect button engages one of the surfaces 124, 125 of one rack only and hence the racks are moved relative to each other. Each rack has a notch 122 which notches are normally aligned and which remain aligned as long as the racks are moved step-by-step by the chosen sequence of buttons and when the last button of the chosen sequence is depressed the notches reach a position which allows a portion 98 of the spring biased member 96 which, as shown, is a bolt lath, to extend through the notches under the urge of the spring which biases a latch bolt 18, coupled to the bolt lath 96, to a releasing position in which it is free of a recess in a door frame and so allows a door 10 carrying the lock to be opened. The portion 98 normally engages an imperforate portion of the nearest rack and remains engage with such portion or with an imperforate portion of the other rack, if the racks are moved relative to each other by incorrect depression of one of the push buttons. The latch bolt 18 is coupled to the bolt lath 96 via a spring 99 so that with the bolt lath 96 in the locking condition the bolt can be depressed by slamming the door. The bolt lath 96 and the racks are restored to the locking condition by depression of a push button 58 which by folding a spring 136 causes the spring to engage a projection 150 of the bolt lath 96 to remove its portion 98 from the notches. The depression of the push button 58 also causes inclined edges 108 of arms 104 carried by the pushbutton to force together the arms of a spring 126; these arms also engage projections 134 of the racks to restore the racks to their locking condition. To allow the control member to be unlocked from the inside of the door and thus allow the automatic retraction of the latch bolt, a push button 152 is provided; depression of this causes a stem 158 to move a lever 174 and this engages the ends of the racks and moves both of them to their unlocking positions in which the notches 122 are aligned with the portion 98. To restore the racks, the bolt lath and the latch bolt to their locking condition from inside the door, a handle 150' is provided and this is connected to the arms 104 which carry a push button 58 so that pulling on the handle 150' has the same result as depressing the push button 58. In a modification a pair of spring members are substituted for the bolt lath 96 and the latch-bolt 18 and upon actuation of the chosen sequence of push buttons in the proper order these are moved to move a member (not shown).