Patent GB-191106285-A (GB)
Title: An Improved Alternating Locking Arrangement.
Inventor: TUA GIACINTO
IPC: E05B63/00
Filed: 1911-03-13
Granted: 1911-11-16
Abstract: 6285. Tua, G. March 13. Catches, automatic. -Relates to means for securing a reciprocating element with respect to a fixed element, and is applicable generally and in particular to electric switches, to supporting devices for lamps &c., and to locks and sliding bolts. The device consists essentially of two toothed wheels 5, 6, one having twice as many teeth as the other, which are secured together on the same spindle and carried by one of the elements, and which are adapted to cooperate with fixed lugs on the other element. Springs, such as the spring plunger 27 shown in Fig. 21, may be provided to steady the wheels. Lock mechanism.-Figs. 6, 7, and 8 show the application of the device to a lock-bolt operated by a key inserted in the keyhole 11. The bolt carries the locking-device 5, 6, Fig. 19, the wheel 5 being shown as having six teeth and the wheel 6 as having three teeth. When the bolt is shot forward from the withdrawn position shown in Fig. 6 to that shown in Fig. 7, a lug 8 on the casing acts on a tooth of the wheel 5 and turns the wheels through slightly less than a sixth of a revolution, as shown, and brings the wheel 6 into a different position relative to the pins 9, 10, so that when the bolt is moved back, the motion is arrested by the wheel 6 contacting with the pins 9, 10 as shown in Fig. 8, and the bolt is held against complete withdrawal. The . pins 9, 10 are placed obliquely as shown, so that the wheel 6 is given a further partial rotation and another tooth of the wheel 5 is brought into the path of the lug 8. When the bolt is again shot forward from the position of Fig. 8, the wheel 6 is turned to the position shown in Fig. 6, and allows the complete retraction of the bolt. A spring may be used to assist the movement of the bolt. Sliding bolts.-In Fig. 3 is shown the device applied to a sliding bolt, the parts being in the position for locking the bolt. In this form, the wheels 5, 6 have four and two teeth respectively When the bolt is to be withdrawn, and is given an initial forward movement, the lug 8 acting on the wheel 5 turns it so that the teeth of the wheel 6 can pass between the pins 9, 10, an extra stop 4 being in this case necessary to limit the backward movement of the bolt. Fastenings for electric switches. -- Fig. 14 shows the application of the invention to the " pear " form of electric switch, the parts being shown in the position in which the circuit is closed. The wheels 5, 6 are carried by the pushrod 1, and when turned by the lug 8 during the inward movement of the rod, the wheel b is adapted to retain the rod with the bridgepiece 17 carried thereby above the contacts 18. By again pressing in the rod, the wheels are turned, and the spring 13 returns the rod to the position shown. Fastenings for lamps.-In Fig. 21 the device is shown as applied to apparatus for suspending electric lamps. The lamp is secured to the part 1 which carries the wheels 5, 6, and is adapted when pulled up to enter a slotted sleeve 2, the teeth of the wheel 6, when turned by the lug 8, being adapted to rest on a band 10 and support the lamp.