Patent GB-190414224-A (GB)
Title: Improvements in or relating to Train Tablet and like Systems of Signalling on Single Line Railways.
Filed: 1904-06-23
Granted: 1905-06-08
Abstract: 14,224. McKenzie & Holland, and Evans, E. 0. June 23. Controlling traffic on railways, staff and ticket systems for.-In a tablet system, as described in Specification No. 17,195, A.D. 1895, in which an intermediate cabin may be closed at certain periods, means are described by which the interlocking lever at the closed cabin may be unlocked, so as to allow the use of levers necessary for shunting purposes, by use of the train tablet. Fig. 2 shows the apparatus as attached to the interlocking lever, and Fig. 3 shows a section through the case G. A double Annett's lock A, A' is attached to the lever Z. The lock A<1>, when its key is withdrawn, locks the bar CR<2> into the notch N in the segment over which the lever Z moves. The cabin is then open. When the cabin is closed, the lever Z is in the position on the right of the Figure, and is locked there by the bar CR operated by the lock k A, engaging the lock c<1> at the other end of the segment. By inserting the train tablet 0 into a slot g in the top of the box G and closing the lid G<1>, which action removes the plate H from the slot j<1> in the bar j, the catches L<1>, L<2> are lifted. The bar j is then pushed inwards and moves the guide J', and through the tablet the guide J<2> and the cranked bars R, S', which are attached to the guide J<2>. A tappet lock releases the bar k with its projection L when the bar j is in its end position, and the bar k is then pushed in. The movement inwards of the bar j causes the inclined face r of the bar R to unlock the Annett's lock A, the wards of which have a cranked extension with inclined faces over which the surface r moves, and so frees the bar CR. At the same time, the end of the bar S' depresses the bar CR<1> against the spring a. This bar can pass over the surface of the segment but meets a projection e on it when the lever is moved over to its mid position. The bar k, when pushed in, lifts by means of the inclined faces D, L, the catch C and with it the bar CR, thus locking the bar R by the catch C entering the notch R<2> ; the lever Z can then be put over until the foot of the bar CR<1> meets the projection e on the segment. In this position, the levers required for shunting are unlocked. To restore the line for through working, the levers are set and the interlocking lever Z is returned to its end position. The bar k is pulled out, thus allowing the bar CR to fall and lock the lever in its position and unlock the bar j. This bar j is then pulled out and moves with it the guide J<1>, which engages the shoulder s on the slide S, to which is fixed the guide J<2> with the bar R. The bar CR' is then lifted by the spring a and a spring in the lock A causes the wards to lock the bar CR in its lower position. The tablet box G may then be opened and the tablet withdrawn, thus returning everything to the original condition of working. The lever Z is locked in its three positions by the catch rod b engaging in the notches N<2>, N', c. A modification of the arrangement for locking the bar j when the lid G<1> is open consists in using a pivoted lid with a sector on the shaft which enters a slot in the bar j when the lid is open.