Improvements in Electrical Locking Apparatus for Railway Signals.
Year: 1899

page_text: Date of Application, 18th July, 1899-Accepted, 19th Aug., 1899
COMPLETE SPECIFICATION.
Improvements in Electrical Locking Apparatus for Railway Signals.
1, GEORGE HENRY JELFS, of No. 35, Fairlawn Avenue, Chiswick, Electrical
Engineer, do hereby declare the nature of this invention and in what manner
the same is to be performed to be particularly described and ascertained in and
by the following statement:-
My invention relates to electrical locking apparatus which can be conveniently
fixed on a railway signal post and is so arranged that the ordinary signal pull
cannot lower the semaphore from its ". danger" position unless an electrical
current be transmitted to the apparatus, or according to a modification the pull
can always lower the signal except when a current is transmitted to the apparatus,
as I shall describe referring to the accompanying drawings.
Fig. 1 is a front view of apparatus such that the signal cannot be lowered
by the pull unless a current be transmitted to the apparatus.
Fig. 2 is a front view of the modified apparatus in which the signal can always
be lowered by the pull except when a current is transmitted to the apparatus.
Referring first to Fig. 1, a is a casing fixed on the signal post; through the
casing past two vertically sliding bars, the front bar b which is connected to the
counterweighted lever below, so that when the signal pull is slacked out this
bar is made to ascend, and the hinder bar c which is connected to the crank
arm of the semaphore above, so that when the bar c ascends, the semaphore is
lowered. On the signal post are fixed two conducting springs d d and on the
front bar is fixed an electromagnet e provided with contacts that can slide
along the springs d d. Also on the front bar is pivotted at f an arm g which
has its lower end jointed to a sliding plate h. The armature i of the electro-
magnet is linked to one arm of a lever j, the other arm of which has jointed
to it a sliding pink immediately over a hole in the plate h. The front bar b
has a slotted hole through which passes a pin m projecting from the back of
the arm g, this pin also passing into a slotted hole in the hinder bar c
hole has an inclined face at n and above it a long slot o.
The apparatus operates as follows:
This
When the electromagnet e is not energised by a current, its armature i drops
drawing the pink out of the hole in the plate h so leaving this plate free to slide.
If now the bar b be raised for the purpose of lowering the signal, the pin m
sliding along the incline n is moved outwards and passes up the long slot with-
out moving the hinder bar and therefore without lowering the signal. But
if the magnet e is energised, its armature being attracted causes the pink to
enter the hole in h so preventing h from sliding. When the bar bis now moved
up, its pin m can no longer move outwards being held by the plate h, and
consequently the bar c is moved upwards along with b and the signal is lowered.
Referring now to Fig. 2 in which the parts corresponding with those in Fig. 1
are marked by similar reference letters, the armature i instead of moving the
pink through a lever, moves it directly so that when the magnet e is energised
the armature being raised takes the pink out of the hole in h, leaving h free

page_text: to slide, and in that case when b is raised the pin m moves outwards and ascends
the long slot o without moving e or lowering the signal. If, however, the
magnet e be not energised then the pin k being engaged in the hole of h pre-
vents from sliding, and consequently the bar b in ascending moves c with it
and the signal is lowered.
Thus in both cases whether the apparatus be arranged as shewn in Fig. 1 or as
shewn in Fig. 2 the upright rod which connects the lever worked by the signal
pull to the crank of the semaphore is divided into two bars which can be con-
nected so as to move together and so operate the signal, or can be disconnected
so as to render the signal pull inoperative as determined by the circuit of an
electromagnet on the signal post being closed or opened.
Having now particularly described and ascertained the nature of this inven-
tion and in what manner the same is to be performed, I declare that what I
claim is =
1. Electrical locking apparatus for a railway signal constructed and operating
substantially as described with reference to Fig. 1.
2. The modified apparatus substantially as described with reference to Fig. 2.
ABEL & IMRAY,
Agents for the Applicant.