Patent GB-189816734-A (GB)
Title: Improvements in Electric Locks and Combination Mechanism therefor.
Inventor: NEWTON PHILIP ARTHUR
Filed: 1898-08-02
Granted: 1899-06-17
Abstract: 16,734. Newton, P. A., [Carleton, H. G.]. Aug. 2. Locks, electrically-controlled latches.-Relates to a latch or lock electrically controlled from a distance adapted to give an alarm when tampered with, the lock being specially suitable for the front door of apartment houses. An electromagnet 10 is mounted on a spring frame C which can be operated from the outside by a knob spindle 15 and follower 16. The spring bolt 17 is separate and carries an armature 22. Normally the operation of the knob spindle has no effect on the bolt, the magnet and frame reciprocating idly, but when an operator in charge completes the magnet circuit at some distant point, the retraction of the frame and magnet causes the armature and bolt to move also, and the door is unlocked. The circuit is made through spring contacts in the door and frame. Two alarms &c. are placed in multiple circuit with the main circuit, one near the lock and the other near the operator's station, these both sounding when the circuit is completed, notifying both the visitor and the operator that the lock is ready to be operated. The opening of the door breaks the circuit and stops both alarms, thus notifying the operator that the door has been opened. Slight modifications of the arrangement of magnet and armature may be made, and the magnet may operate the striking-plate instead of the bolt. An electric combination mechanism may also be applied to the lock or to any form of electric lock. Fig. 15 shows a diagrammatic view of the circuits when two discs are used. The discs are set by feeling, having notched edges engaged by spring detents, the notches being arranged so that 'zero' can easily be felt. The discs are then turned through the necessary amount, indicated by the detents slipping past a known number of notches. The discs are adjustably fixed on spindles 41, so that the combination may be altered. The spindles 41 each carry a contact-maker consisting of a metal disc 54 with a notch 56 plugged with insulating-material, and an insulating-disc 53 with a metal pin 55 passing through it. Spring contacts 59, 60, 61, 62 bear on the contact-makers as shown, the spring 62 having jaws 63, 64. When the combination is correctly set, the contact-makers occupy the position shown, and by closing the circuit at 67 the lock may be opened, the main circuit being completed through the battery, contact 60, upper pin 55, jaws 63 of spring 62, lower pin 55, and contact 61. In this case an alarm circuit 68, attached to the battery and to the upper spindle 41, is not completed, as the end of the spring 59 rests on plugs 56. Should one of the discs, say the lower, and consequently its contact-maker, be incorrectly set, the lock circuit is broken by the lower pin 55, and on closing the circuit at 67 an alarm circuit is set up through the battery, wire 66, contact 59, lower metal disc 54, jaws 64 of spring 62, upper disc 54, spindle 41, and wire 68, notifying anyone in charge that the lock is being tampered with. A modified form of contact-maker is described, the circuit-closer 67 being dispensed with and the circuit completed to operate the lock by a slight turning of the knob spindle, the follower 16 acting on spring contacts in the lock and closing them before retracting the magnet. To prevent the combination mechanism and lock from being removed from the door, a second cover-plate 69 is provided, insulated from the casing 40. Screws 71, with heads 70 and enlarged ends 72, are screwed into the casing 40, and, when unscrewed to remove the plate 69, complete a circuit, shown in dotted lines, between the plate and casing and sound an alarm.