GB1201160A - Improvements in and relating to magnetic lock mechanisms - Google Patents

Abstract

1,201,160. Magnetic locks. HUWIL-WERKE HUGO WILLACH & SOHNE, 13 Nov., 1967 (19 Nov., 1966; 21 Sept., 1967], No. 51602/67. Heading E2A. A lock mechanism comprises an outer member having a cylindrical recess, an inner cylindrical member partly disposed in the recess, the inner and outermembers being relatively movable, a coupling member for actuating a bolt mechanism, a permanently magnetised tumbler which is movable by means of a permanently magnetized key between an unlocking position in which the coupling member is movable by movement of one of said members and a locking position in which the coupling member cannot be so moved, and a ferro-magnetic keeper fixed to said one member and which retains the tumbler in the locking position. In a first embodiment, Fig. 1, the outer member 1 is stationary and contains the inner member 3 which is rotatable and has a cavity therein for receiving the key 4; the members 1 and 3 are both provided with radial bores 5, each bore 5 of the member 3 being aligned in the locking position with a corresponding bore of the member 1 and each said pair of aligned bores containing a magnetised said tumbler 6, the tumblers preventing rotation of the member 3 relative to the member 1. To release the member 3 the key has its shank entered into the cavity, the key having a number of magnetic poles which correspond in position to the tumblers and the polarity of which is such as to repel the tumblers so that they are wholly contained in the radial bores 5 in the member 1; the member 3 can then be rotated so that the coupling member 3a carried by it can withdraw the bolt of a bolt mechanism. When the inner member 3 is returned to the locking position the tumblers are attracted to the locking positions by a said keeper 7 in the bottom of each of the bores of the inner member. The key magnets are more powerful than the tumbler magnets and have to overcome the force of attraction of the tumblers for the keepers 7. In a second construction Fig. 3 the outer member 21 contains the coupling member 22 which in turn contains the inner member 23. The inner member 23 has two recesses 23b on opposite sides of a key cavity 23a and each in the locking condition of the. lock mechanism, contains a said magnetised tumbler 26 so that the inner member with the tumblers is freely rotatable in the coupling member 22. When the key is inserted into the key cavity the tumblers 26 are repelled by the key and partly enter cavities 22b in the coupling member 22, so coupling the inner member to the coupling member 22 which can then be rotated to withdraw the bolt of a bolt mechanism. To return the tumblers 26 to their locking positions wholly in the cavities 23b, a said keeper 27 is provided in the bottom of each cavity which moves the respective tublers 26 to the locking position by the force of magnetic attraction between the keepers and the tumblers 26. In a modification of this construction the two tumblers 26 have a different number of magnetic poles and the key has its magnets so disposed that only one of the tumblers 26 is moved by the key for coupling the inner member to the coupling member 22, the other tumbler 26 is moved by a different key and one of the keys can be a pass key common to a suite of lock mechanisms. In a third construction Fig. 6 the inner member is in the form of a push button 122 which is slidable but non-rotatable relative to the outer member 120 and the coupling member 125 is slidable but non-rotatable relative to the push-button. An end portion of the member 125 projects from the outer member and its other end portion enters a bore in the push button. The member 125 has a recess 128 in its periphery which in one position of the member 125 relative to the push button is aligned with a recess 130 in the wall of the bore of the push button. When the lock mechanism is in the locking condition the recess 130 wholly contains a said tumbler 131. Underneath the recess 130 is a key pocket 134 which receives the key 132 and to unlock the mechanism the push button is first depressed against the pressure of a spring 121, this depression aligning the recess 130 with the recess 128 of the member 125. The key 132 is then entered into the pocket 134 in a position such that the magnets of the key repel the tumbler 131 which then partly enters the recess 128 in the member 125 and partly remains in the recess 130 in the push button so that the push button is coupled to the member 125; the push button when released then takes the member 125 with it so that its end portion is retracted into the casing. The tumbler is retained in the recess 128 by a said keeper 129 in the base of the recess, and to place the lock mechanism in the locking condition the key has to be inserted into the key pocket in such a position that its magnets attract the magnets of the tumbler, the magnetic force of the key being sufficient to overcome the attraction of the tumbler for the keeper 129. This attraction of the key pulls the tumbler wholly into the recess 130 and if the push button is then depressed the member 125 is restored to its locking position, release of the push button leaving it in such position. The recess 130 is also provided with a said keeper 129 so that the tumbler is retained in the recess in the locking condition by its attraction for the keeper 129. In a fourth construction Fig. 10 the outer member is in the form a knob 42, is rotatably mounted on a shaft 40 and a coupling member 44 which carries a follower 45 for bolt operation is contained in a bore in the shaft 40; the transmission member 44 has an enlarged head 46 contained in a recess in the shaft 40 and the knob has a recess 55 which, in the locking condition, in which the knob is freely rotatable, contains a said tumbler 48. The tumbler is repelled so that it partly enters a recess in the head 46 of the coupling member and partly remains in the recess in the knob by a magnetised key 51 which can be disposed in a recess in the end portion of the knob; the knob is then coupled to the coupling member so that a bolt can be withdrawn by the follower 45. A said keeper 49 is contained in the bottom of the recess in the head 46 and also in the bottom of the recess in the knob and one keeper holds the tumbler in the locking position and the other in the unlocking position. The key magnets have to be sufficiently powerful to overcome the attraction of the tumbler for the keepers. The tumbler is restored to the unlocking position by reversing the position of the key so that the key attracts the tumbler instead of repelling it.