Patent GB-190523239-A (GB)
Title: Improvements in Latches and in Self Closing Locks.
Inventor: NATHAN ARTHUR
Filed: 1905-11-13
Granted: 1906-02-08
Abstract: 23,239. Nathan, A., Schlomann, A., and Silberberg, H. Nov. 13. Locks, key; latches; fastenings, railway-carriage door.-In Fig. 1 is shown a fastening, applicable to railway-carriage and other doors, in which two bolts t and r are used, each being of bell-crank shape and pivoted to the lock case as shown. The bolts are shown fully shot in Fig. 1. By turning the follower by means of the handles, the arm e acts on the pin y on the bolt t and partly withdraws the latter till the lug g thereon is moved out of the path of the projection o on the bolt r. The arm z of the follower now comes in contact with the part x of the bolt r and commences to withdraw the latter, while at the same time the pin y is released from the follower arm e, as shown in Fig. 4, and the bolt t partly shoots out, so that the lug g is brought in front of the projection o. By the continued rotation of the follower, the bolt r is completely withdrawn, and by reason of the engagement of the pin p thereon with the lug q on the bolt t the latter is also withdrawn, and the door can be opened. On releasing the handle, the bolts return to the latching position where they are held by the stop g coming in contact with the projection o as shown in Fig. 4. When the door is slammed, the bolts are pushed in, and the spring w being so arranged as to exert a greater pull on the bolt r, the latter shoots forward first and in so doing carries the projection o beyond the lug g on the bolt t and allows both the bolts to shoot out to their full extent as shown in Fig. 1. In Fig. 8 is shown the device arranged as a hall-door latch and lock. In place of the rotary handle, a pivoted handle in the form of a bell-crank is used to operate the bolts from the inside. The handle operates a slide a which communicates motion to the lever d, the arm e<1> of which acts on the end f of the bolt t and partly withdraws the same till the lug g<1> thereon registers with the opening h in the gating h<1> of the bolt r. By this time, the projection l on the slide a has raised the levers k so as to bring the slot m therein into register with the projection n on the bolt r, and the top of the slide a has come into contact with the part i of the bolt r. By continued pressure on the handle, the slide a operates the bolt r, the stump n travelling along the slot m of the levers, until the midposition, as in the first case, is reached. Both bolts are completely withdrawn by further pressure on the handle, the bolt t being operated through the bolt r by means of the pin p<1> on the latter. From the outside, the same operations are performed by the flat double-butted key shown in Fig. 10, which takes between the spring arms s and simultaneously operates the levers and withdraws the two bolts. The door is securely locked on being slammed in the same way as described above. In a modification, a similar lock is used without the locking-levers, and is provided with means for keeping the two bolts in their latching position. For this purpose, a tapered pin is inserted from outside, through the casing into a slot in the bolt r, and keeps the bolts in their partly withdrawn positions. Both bolts being double bevelled at their-ends, permits of the door being opened and closed by pressure only.