Improvements in Semaphore Signals.
Year: 1890

page_text: Date of Application, 6th Dec., 1890
Complete Specification Left, 5th Sept., 1891-Accepted, 14th Nov., 1891
PROVISIONAL SPECIFICATION.
Improvements in Semaphore Signals.
I, HENRY ERNEST LAFOREST, of 16, Rue Meslay, Paris, in the Republic
of France, Merchant, do hereby declare the nature of this invention to be as
follows:-
:-
My invention relates to apparatus for operating semaphore signals.
The apparatus heretofore used on railway lines for operating semaphore signals
are arranged in such a manner that the stopping of the. semaphores is effected
automatically under the action of a counter-weight when the employee charged
with the operation of the signals acts by means of a handle upon the wire which
actuates a signal. The counterweight has the effect of automatically stopping the
semaphore but its action gives rise to shocks and vibrating movements which
fatigue all the parts of the semaphore such as the pole the boring-rod, and the
lantern with its frame.
For obviating these inconveniences and effect automatically without noise or
shocks the stopping of the semaphores I replace the counterweight by a device in
which a spring or preferably two combined springs are employed, a quantity of air
which is contained in a cylinder behind a piston acted upon by the said spring or
springs constituting an elastic cushion whereby an abrupt stoppage of the semaphore
is prevented.
This improved apparatus may be carried out in various manners. By way of
example will describe an apparatus in which the axis of the semaphore is
attached to the piston of the stopping device by means of a connecting rod.
The stopping device comprises a cylinder provided with covers at its two ends
and with a piston in its interior. Two concentric springs are arranged between
the piston and an abutment plate held in the cylinder through the medium of a
screw which enables the position of the said abutment plate to be regulated. This
screw has a bore in it to serve as a guide for the rod which is connected with the
arm on the axis of the boring rod of the signal through the medium of a connecting
rod. As usual, to this arm is attached the wire for operating the semaphore.
The cover at the rear of the above mentioned cylinder is provided with a screw-
threaded plug presenting two oblique lateral slits or. grooves so that orifices are
formed which become smaller the further the plug is screwed into the cover.
When the said wire is pulled for turning the semaphore the air passes around
the piston rod and around the leather packing of the piston to the rear of the
piston and when the wire moves back the stoppage of the semaphore is caused
automatically by the springs the air behind the piston being able to escape through
the small slits or arrows in the aforesaid screw so that this air cushion is opposed
to an abrupt stoppage of the semaphore.
The piston rod may also be connected directly with the above-mentioned arm rod
in which the said cylinder is arranged between vertical axes or pivots adapted to
turn in a fixed frame.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicant.

page_text: COMPLETE SPECIFICATION.
Improvements in Semaphore Signals.
I, HENRY ERNEST LAFOREST, of 16 Rue Meslay, Paris, in the Republic
of France, Merchant, 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 apparatus for operating semaphore signals.
The apparatus heretofore used on railway lines for operating semaphore and
other signals are arranged in such a manner that the return of the semaphores or
other signalling devices is effected automatically under the action of a counter-
weight after the attendant in charge has operated the signal by means of a handle.
The counterweight has the effect of automatically returning the semaphore to its
original position but its action gives rise to shocks and vibrating movements which
strain or fatigue all the parts of the semaphore device as for instance, the pole, and
the lantern with its frame.
For obviating these inconveniences and to automatically effect the gradual
return of the semaphores without noise or shock I replace the aforesaid counter-
weight by a device consisting of a cylinder in which is arranged a spring or
preferably two combined springs acting on a piston for automatically causing the
backward movement of the signal, the said backward movement being retarded by
the air behind the said piston which is only allowed to escape slowly, thus forming
an elastic cushion whereby an abrupt stoppage during the return movement of the
semaphore is prevented.
In the accompanying drawings I have shown how my said invention may be
conveniently and advantageously carried into practice.
Figure 1 is a side elevation showing the application of my invention to disc
signals.
Figure 2 is an end elevation of the same.
Figure 3 is a plan thereof.
Figure 4 is a vertical section of the stopping or retarding device drawn to an
enlarged scale.
Figure 5 is a transverse section and
Figure 6 is a horizontal section of the same, and
Figure 7 is a modification of the device applied to a semaphore.
The said stopping or retarding device comprises a cylinder A provided with
covers B and C and with a piston D provided with a valve v in its interior. Two
concentric springs R R are arranged between the piston D and an abutment
plate E held in the cylinder F by means of a screw which enables the position of
the said abutment plate E to be regulated. This screw is provided with a hole
which serves as a guide for the piston rod T which is connected with the arm m
on the vertical rod o of the signal through the medium of a connecting rod b.
To the arm m is attached the wire f for operating the semaphore in the usual
manner.
The cover C at the rear of the above-mentioned cylinder A is provided with a
screw-threaded plug a having two slits or grooves d d forming orifices which
become smaller the further the plug is screwed into the cover.
When the said wire f is pulled for turning the semaphore the air passes around
the piston rod T and around the leather packing c of the piston to the rear of the
piston D and when the wire moves back the return of the semaphore is effected
automatically by the springs R the air behind the piston D being allowed to escape
only through the small slits or grooves d, d, in the aforesaid screws so that the air
cushion thus formed will oppose the abrupt and jerky stoppage of the semaphore.
The piston rod may also be connected with the above mentioned arm in which
case the said cylinder A is arranged between vertical axes or pivots adapted to
turn in a fixed frame.

page_text: Figure 7 shows a modification of the device as applied to an ordinary railway
arm signal or semaphore. The ordinary counterweight of semaphores is replaced
by a vertical cylinder A having a spring; the piston rod T is connected with the
rod. T¹ which actuates the arm of the semaphore by means of a stirrup o. The
cylinder A is fixed to the pole at the two extremities by two lugs cast in one piece
with the covers which close the cylinder.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
First. The herein described automatic device for gradually effecting the return
movement of railway signals consisting of one or more spiral springs arranged
within a cylinder and acting upon a piston, the said cylinder containing air which
by its compression and by the means for allowing of its gradual escape, forms a
cushion and prevents the abrupt return of the signal.
Second. The herein described device for effecting the return movement of
railway signals consisting of a cylinder and piston and a spring or springs the said
cylinder being fixed or pivoted and arranged in a vertical or horizontal position
substantially as above described with reference to the drawing.
Fourth. The hereinbefore described device for automatically effecting the return
movement of a railway arm signal or semaphore signals substantially as and for the
purpose above specified.
Dated: il
fb 1901
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.