GB161694A - Improvements in locking devices for levers controlling railway, tramway and similar signals and for other like purposes - Google Patents

Abstract

161,694. Downes, F., Cooke, C. J., and Rogers, W. D. Jan. 16, 1920. Hand.levers and hand gearing. -Hand-levers for railway and similar signals and points are locked by two suitably-shaped jaws pivoted to a bolt which is under the control of a member operated by an electromagnet. The frame 1 carries the electromagnet 2 at one end and is slotted at the other end 3 to permit movement of the lever 4. A bolt 8 slides in guides 9 and has pivots 6 carrying the locking jaws 5 which are slotted at 10 to pass over pins 11 on the frame. A pivoted locking member 12 is pushed by the overhanging bar 13 into a recess in the bolt, and depresses the lever 15 to withdraw the armature 16 from the electromagnet 2. To prevent the mechanism from being restored to the locking position unless the lever 4 is held by the jaws 5, one end of a lever 17 is pulled by a spring 19 across the slot 3 in the frame through which the hand-lever moves, and the other end is moved to hold the armature 16 against its magnet. When the electromagnet is energized, its armature is attracted and tends to lift the member 12, but is prevented from doing so by the bar 13. As, however, the lever is moved forwards, the bolt 8 follows under the action of the spring 19 and, owing to the shape of the slots 10 in the locking jaws 5, releases the lock upon the handle. The lock may be constructed with only one jaw instead of two.