Improvements in Apparatus for Ensuring Safety on Single Lines of Railway.
Year: 1894

page_text: Date of Application, 20th July, 1894
Complete Specification Left. 29th Mar., 1895-Accepted, 4th May, 1895
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Ensuring Safety on Single Lines of
Railway.
I, EDWARD TYER, of Ashwin Street, Dalston, in the County of London,
Electrical Engineer, do hereby declare the nature of this invention to be as
follows: :-
In my previous Specifications Nos. 1262 of 1878, 42 of 1888, 5928 of 1890,
1904 of 1891, 18603 of 1891, 2798 of 1892 and 12144 of 1893 I have described
apparatus for ensuring safety of traffic on single lines of railway by electrically
controlling the issue from a station of a tablet or staff to be carried by a train to
a station beyond, thus providing against the admission of more than one train to the
section of the line extending between the connected stations.
My present invention relates to modifications of apparatus for this purpose
having for their object to simplify the electrical appliances and connections and to
lessen cost without impairing efficiency. I shall describe the nature of the modified
apparatus adapted for use with a staff.
Usually, when trains coming to station A alternate with trains going to station B
only one staff is employed, this being carried to and fro with each train and no
controlling apparatus being required.
If, however, when the staff is brought by a train from B, the distant station, the
signalman there desires to issue a staff for another train from B, he signals to the
operator at A who then proceeds as follows. He opens a lid covering an aperture
to his apparatus, and by doing so he breaks a contact and thus prevents electrical
communication with B. Through the opening thus uncovered he inserts the staff
and, by clesing the lid, restores the contact and removes a catch allowing the staff
to slide down an incline. The staff, in sliding, passes over a spring lever by which
an armature is moved up to an electromagnet, this armature making a contact by
which the coil of the electromagnet and also the coil of an electromagnet at B are
connected to line, and the armature being attracted is held in position maintaining
this connection.
An instrument at B now shows that a current is passing along the line, and thus
the signalman at B is apprised that the staff is shut into the apparatus at A. and
cannot be issued to a, train, and also that his own apparatus is free for issue of a
staff. He thereupon pushes down a plunger of his apparatus, which is similar to
that at A, and by this action he pushes aside a spring catch releasing a staff which
descends into an accessible part of his apparatus, at the same time breaking an
electrical contact, thus opening the line circuit and rendering inoperative both of
the electromagnets above referred to. When a large number of staves is required,
the incline down which they slide and on which they are accommodated may be
made as a helix, like a spiral staircase.
By suitable modifications the apparatus can be adapted for operating with
tablets.
Dated this 20th day of July 1894.
ABEL & IMRAY,
Agents for the Applicant.

page_text: :
COMPLETE SPECIFICATION.
Improvements in Apparatus for Ensuring Safety on Single Lines of
Railway.
I, EDWARD TYER, of Ashwin Street, Dalston, in the County of London,
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 :--
In my previous Specifications Nos. 1262 of 1878, 42 of 1888, 5928 of 1890,
1904 of 1891, 18603 of 1891, 2798 of 1892, and 12144 of 1893 I have described
apparatus for ensuring safety of traffic on single lines of railway by electrically
controlling the issue from a station of a tablet or staff to be carried by a train to a
station beyond, thus providing against the admission of more than one train to the
section of the line extending between the connected stations.
My present invention relates to modifications of apparatus for this purpose
having for their object to simplify the electrical appliances and connections and to
lessen cost without impairing efficiency. I shall describe the nature of the
modified apparatus adapted for use with a staff referring to the accompanying
drawings.
Fig. 1 is an elevation of the mechanism within a casing the front of which is
removed to shew the interior.
Fig. 2 is a plan, the cover of the casing being removed.
Fig. 3 is a diagram of the electrical connections.
It is to be understood that there is a set of the apparatus at each of two stations A
and B connected by the line wire.
Usually, when trains coming to station A alternate with trains going to station B,
only one staff is employed, this being carried to and fro with each train and no
controlling apparatus being required.
If however, when the staff is brought by a train from B the distant station, the
signalman there desires to issue a staff for another train from B, be signals (by
sending a current which passes through line and the instrument I to earth) to the
operator at A. who then proceeds as follows:
He opens a lid L covering an aperture to his apparatus, and when he does this
a pin or roller on an arm of the lid acting on a curved lever depresses it to the
position indicated by the dotted lines also another arm of the lid pushes down
another lever which breaks a contact and thus prevents electrical communication
with B.
Through the opening uncovered by raising the lid L the operator at A inserts
the staff which is held in the dotted position S' by a horn projecting from the
lever until the lid is closed whereupon the levers and are raised by their
springs restoring the contact and allowing the staff S¹ to slide down an incline S.
The staff, in sliding, passes over a spring lever C by which an armature C¹ is
moved up to an electromagnet E this armature C' making a contact at c by which
the coil of the electromagnet E is connected to one pole of a local battery and to
line, and the armature C' being attracted is held in position, maintaining this
connection.
'
The instrument I at B now shows that a current is passing along the line, and
thus the signalman at B is apprised that the staff is shut into the apparatus at A,
and cannot be issued to a train, and also that his own apparatus is free for issue of
a staff.
The current transmitted by the line excites in B's apparatus an electromagnet F,
the armature F¹ of which is usually engaged in a notch at the side of a spring
plunger R¹ preventing it from being pushed to the left. But when the magnet F is

page_text: excited its armature is withdrawn from the notch leaving the plunger R¹ free. The
operator at B, being informed by his instrument I that the plunger R' is free,
pushes down a plunger P the oblique end of which entering between the lowest
staff S and that just behind it, pushes S to the left against a roller R on the spring
plunger R. which is thus also pushed to the left, and finally the staff S reaches the
dotted position S' where it descends into a part of the apparatus accessible by a
door D; at the same time the movement of the plunger R' breaks an electrical
contact tbus opening the line circuit and rendering both sets of apparatus
inoperative.
When a large number of staves is required the incline down which they slide and
on which they are accommodated may be made as a helix, like a spiral staircase.
By suitable modifications, the apparatus can be adapted for operating with
tablets.
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 :-
Apparatus for ensuring safety on single lines of railway by electrically coutrolling
from one station such as A the issue of a staff or its equivalent at another station
such as B, this electrical control being effected by introducing into apparatus at A
a staff or its equivalent and thereby operating contacts which cause automatic
release of a staff or its equivalent in the corresponding apparatus at B, substantially
as described.
Dated this 26th day of March 1895.
ABEL & IMRAY,
Agents for the Applicant.