GB639314A - Improvements in or relating to locks - Google Patents

Abstract

639,314. Locks. EVENNETT, F. F. June 28, 1948, No. 17275. [Class 44] The spindle of a barrel-type lock is secured by a series of spring loaded tumblers slidably mounted on a square section portion of the spindle and having projections engaging openings in a fixed housing, the tumblers being displaced to withdraw the projections by a key inserted in a slot in the spindle. In the form of Fig. 11, the spindle S has' cylindrical parts 1, 2 bearing in openings in the housing H and the face plate T. Between the parts 1 and 2 the spindle is square and carries a series of tumblers W. In the form shown there are four tumblers separated by -distance pieces 3. Each tumbler has a rectangular opening 4 in which is a lug P for engagement in the slot 5 of the spindle. Oppositely projecting lugs E, E 2 on the tumblers, of varying lengths but of constant total length, are adapted to engage in openings 6 in the housing H under the influence of the tumbler springs D. Alternate tumblers are oppositely disposed so that the projections P are engaged by opposite sides of the key, Fig. 9, and displaced thereby an amount sufficient to withdraw the lugs E, from engagement with the openings 6 but insufficient to cause the lugs E to engage the opposite openings. The spindle may then be turned by the key. A spring loaded cam meber X has a rounded part co-operating with the openings 6 to locate the spindle in a position in which it may be locked. In another form, the spindle has a pair of slots at right angles and a number of tumblers are arranged thereon each at right angles to those on either side and are actuated by a four bladed key. In a modification the tumblers are not spring loaded but are accurately positioned by opposite projections such as P engaging opposite sides of the key. The lock spindle carries a cam member Y adapted to lock the latch bolt Z, Fig. 13, by engagement behind the bolt, or to retract it by engagement with a roller 7 on the lock plate 8. In the intermediate vertical position of the cam Y the bolt is free for retraction by the handle follower. As applied to a drawer lock, the spindle carries an eccentric pin engaged in a slot in the lock bolt. In a padlock, Fig. 17, the eccentric pin 9 engages in a slot 10 in a pivoted bolt 11, a tooth 12 on the bolt being adapted to engage a notch in the hasp.