Improvements in and appertaining to Automatic Signalling on Railways or like Places.
Year: 1898

page_text: Date of Application, 22nd Aug., 1898
PROVISIONAL SPECIFICATION.
Improvements in and appertaining to Automatic Signalling on
Railways or like Places.
! 1 !
"I, ELIJAH SALTHOUSE, of 13, St. Michael's Road, Liverpool, in the County of
Lancaster, Electrical Engineer, do hereby declare the nature of this invention
to be as follows:-
My invention has for its principal object to simplify the arrangement and con-
struction of apparatus for automatically signalling, on railways, and it may be
applied to tramways, cable railways or the like. Some parts of my apparatus
are actuated mechanically and others electrically and the main advantages of my
apparatus are economy of energy and freedom from liability to derangement from
atmospheric causes, and the effects of wear and tear. There is also a great
economy in the first cost of cabling.
My apparatus comprises semaphore or equivalent signals arranged at any usual
or desired points adjacent to the track. A train in passing one of these mechanically
releases the semaphore arm and causes it to assume the danger position, and at or
near the same point closes a circuit by actuating a switch and this opens the
section in the rear by depressing the arm of the signal at the commencement of
said section. The precise cycle or number of semaphores actuated by a train in
passing through a section of the line forms no part of my invention and may vary
with circumstances.
Referring more particularly to each signal. It comprises a post (when neces-
sary) and on this post is pivotted the semaphore arm. A rod connected to the
arm back of its pivot is so arranged that when said rod rises the arm falls, and so
on. In some convenient place on the post the rod at its lower end enters a casing
and a weather proof cowl attached to said rod rises and falls over a chimney-
like portion of said casing, and in this manner entrance of rain etcetera is pre-
vented. Attached to the lower end of the rod is a soft iron weight which also
forms the core of a solenoid, and it will be seen that when the circuit is closed
by the train as above mentioned, the coil of the solenoid becoming energised raises
the core and with it the rod and thus lowers the semaphore in question. One
portion of the rod is formed as, or carries, a toothed rack which meshes with a
ratchet pinion running idle on a fixed supporting spindle. A pawl is so arranged
relative to the pinion that when the rod is rising it rides over the teeth of said
pinion, but when the current (which is applied little more than momentarily)
ceases, and the core and rod tend to drop, the pawl prevents it, and the semaphore
thus indicates line clear till again released.
In proximity to the pawl I provide a tripping lever which is connected by suit-
able elbow levers and rods or links with the mechanical breaker by means of
which the semaphore is again released to danger position by a striker on the
train. This breaker comprises a plate or short rail (having bevilled ends to
reduce the shock of 'impact) supported on a rocking lever near the track.
In some cases as an additional precaution the pulling off circuit for one section
may pass through a switch carried on the signal protecting the next section,

page_text: so that it will be impossible for the section in the rear to be cleared until
the starting signal in the advance section is in the danger position. I prefer
that the switch shall be actuated by the movement of the rod above described
as that has a comparatively large motion, and will therefore keep the circuit open
unless the semaphore is properly home at the danger position. I am aware that
it has hitherto been proposed to use the precautionary measure described and I
make no claim to the mere application of such a principle, but I find in practice
that by utilizing the rod to move the switch, a large stroke is obtained and a
more sensitive and certain switch produced that heretofore.
I wish to point out that it is only for an extremely short space of time that
an electric current is needed to release the signal, and this besides being very
economical minimizes the trouble that exists in some systems of signalling in
which the energy needs to be constantly expended to maintain a desired position
of the semaphore, and moreover the placing at danger is effected mechanically.
Where electric traction is used the line current may be utilized to energise
the solenoid which cannot be safely done as far as I am aware with existing
systems. With my apparatus a break down of current or a short circuit would
merely "fail" the signals whose contacts were being passed and would leave them
at danger.
The precise details of construction may vary in different situations.
Improvements in and appertaining to Automatic Signalling on
Railways or like Places.
I, ELIJAH SALTHOUSE, of 13, St. Michael's Road, Liverpool, in the County of
Lancaster, but now of Easton Street, Wycombe, in the County of Bucks, 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 has for its principal object to simplify the arrangement and con-
struction of apparatus for automatically signalling on railways, and it may be
applied to tramways, cable railways or the like. Some parts of my apparatus
are actuated mechanically and others electrically. The main advantages of my
apparatus are economy and energy and freedom from liability to derangement
from atmospheric causes and from the effects of wear and tear. There is also
a great economy in the first cost of cable.
My apparatus comprises semaphore or equivalent signals arranged at any usual.
or desired points adjacent to the track. A train or engine in passing one of
these mechanically releases the semaphore arm and causes it to assume the danger
position and further on closes a circuit by actuating a switch, and this opens
or clears the section in the rear by depressing the arm of the signal at the com-
mencement of said section. The precise cycle or number of semaphores actuated
by a train in passing through a section of the line forms no part of my invention
and may vary with varying circumstances.
I shall describe how my invention may be carried into effect, Fig. 1 being
a vertical cross section of a signal post and my apparatus connected therewith
and Figs. 2, 3 and 4 detail views.

page_text: A represents a signal post or other part to which is pivoted the double armed
semaphore lever B. A rod C connected to the rear arm of the semaphore lever is
so arranged that when said rod rises the signal arm falls and vice versa. This
rod, if its weight be not sufficient may be provided with a weight. In some
convenient place on the post the rod C at its lower end enters a casing 1) and a
weather cow! E attached to the rod C rises and falls over a chimney like portion ])'
of the casing and by this means the entrance of rain and other injurious matter
is prevented. Attached to the lower end of the rod C is a soft iron armature F
which also forms the core of a solenoid G and if necessary a counterweight and
it will be understood that when the solenoid circuit is closed by the engine or
other vehicle of a train actuating a lever S suitably mounted say on a bracket S¹
which is in connection with a switch T, the coil of the solenoid G becomes
energized and draws up the core F and with it the rod C, whereby the semaphore
signal arm B is lowered. One portion of the rod C is formed as or carries a
toothed rack C which meshes with a ratchet pinion H running idle on a fixed
supporting spindle I. A pawl K is hinged or mounted on a lever L in such
manner as to permit the pinion H to revolve past it in one direction and is so
arranged relatively to the said pinion that when the rod C is rising the pawl rides
over the teeth of the pinion, but when the momentary current ceases, and the
core F and with it the rod C tend to drop, the pawl K prevents it taking in
between the teeth of the said pinion and the semaphore thus indicates line
clear" till the pawl K is again released.
Near the pawl K I provide a tripping lever L which by suitable rod and lever
gear as for instance the rod M, the bellcrank lever N and the rod O is connected
with the mechanical releaser or breaker by means of which the semaphore is again
released to danger position by a striker on the train such for instance as the
striker P shewn in Fig. 3 which is attached to the underside of the engine or one
of the carriages. The releaser comprises a plate or short rail Q having bevelled
ends to reduce the shock of impact and supported on a rocking lever R on or
near the track. Instead of the rail Q a wheel Q₁ as shown in dotted lines may
be mounted on the lever R. Instead of also using the pinion H as a pawl wheel
I may in addition to the pinion provide a separate pawl wheel having only one
tooth space or recess as shown in Fig. 4, the advantage of which is that if the
semaphore arm were slow in going to the danger position there could not be
a sticking in the halfway position as might happen with the other plan by the
pawl passing into one of the tooth spaces of the pinion.
In some cases and as an additional precaution the line wire in connection with
the starting signal of the section last left by the train passes through a switch
carried on the signal in the section into which the train has just passed so that
it will be impossible for the signal in the section in the rear to be put at clear
until the starting signal in the advance section is in the danger position. I
prefer that the switch should be actuated by the movement of the rod C as the
latter has a comparatively large movement and will therefore keep the circuit
open unless the semaphore is properly home at the danger position. I am aware
that it has hitherto been proposed to use the precautionary measure described and
I make no claim to the mere application of such a principle but I find in practice
that by utilizing the rod C to move the switch, a large stroke is obtained and a
more sensitive and certain switch produced than heretofore.
I wish to point out that the semaphore or signal is normally held at the
danger" position by gravity, it is only for an extremely short space of time
that an electric current is needed to put the signal to
clear" where it is held
by the pawl and this besides being economical minimizes the trouble that exists
in some systems of signalling in which energy needs to be constantly expended
to maintain the semaphore at the "clear" position.
Where electric traction is used, the line current may be utilised to energize the
solenoid which cannot be safely done as far as I am aware with existing systems
With my apparatus a breakdown of current or a short circuit would merely "fail"

page_text: the signals whose contacts were being-passed and would leave them at danger
without effecting the others.
bod
The precise details of construction-may vary in different situations.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed I declare that what
I claim is:
-
1. A semaphore or equivalent signal a rod connected thereto a solenoid for
pushing up said rod when the solenoid is energized and thereby raising the sema-
phore to the "clear" position in combination with a switch in the solenoid circuit
for opening the section or sections in the rear by depressing the arm of the signal
at the commencement of said section tripping gear for releasing the rod to allow
the semaphore to go to the danger position and a mechanism which is connected
to the tripping gear, and adapted to be actuated by a wheel or other part on a
passing train; substantially as set forth.
.
2. A rod connected to the semaphore-or equivalent signal, said rod provided
with a toothrack and its lower end forming the weighted core of a solenoid, a
tooth wheel gearing with the rack, pawl gear for retaining and releasing the tooth-
wheel, said gear connected to a lever adapted to be actuated by a wheel or other
part on a passing train, in combination with a switch in the solenoid circuit,
substantially as and for the purpose set forth.
3. The construction of apparatus shewn on the drawing.
D
this 22nd day On June 10.
JENSEN & SON,
77, Chancery Lane, London, W.C., Patent Agents.