improvements in and relating to Semaphore Signals.
Year: 1886

page_text: improvements in and relating to Semaphore Signals.
I, HENRY HARRIS LAKE, of the firm of Haseltine, Lake, & Co. Patent Agents,
Southampton Buildings, in the County of Middlesex, 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 :-
This invention has relation to Semaphore Signals for Railways, and pertains to
that class of signal in which is employed a swinging or pivoted arm or blade,
capable of assuming different positions and thereby indicating the several
conditions of "danger," "caution" and "safety" according to its position.
The advantages of the swinging arm or blade as a signalling expedient for
railways are so well understood and appreciated that reference to the same is
unnecessary.
The swinging arm is the only medium in use or capable of practical employment
which will indicate with certainty by its position as well as by its color the
conditions required to be understood in order to ensure safe and expeditious travel
on railways.
This invention contemplates the adaptation and employment of the swinging
semaphore arm or blade for night as well as day signalling, in all situations and
under all conditions where such a device may be made available and used to
advantage, and the said invention accordingly consists:
Firstly, of a semaphore signal comprising a hollow or box like signal arm or
blade having one or both sides covered or closed by glass or other transparent
medium in different colors, secondly, in the combination with a semaphore signal
comprising a hollow or box like swinging arm or blade having one or both its
sides covered by glass in different colors of a screen or slide by the movement or
adjustment of which different colors may be exposed: thirdly, in the combination.
with a semaphore signal having one or both its sides covered or closed by glass or
other transparent medium in different colors or alternately opaque and clear, of
a color changing slide or screen which will move automatically and change the
color of the exposed light to correspond with the position of the arm or blade and

page_text: indicate the same conditions, and fourthly, in the novel construction, combination
and arrangement of parts hereinafter described.
Referring to the accompanying drawings, illustrating this invention,
Fig. 1 is a side elevation of a signal post and swinging arm, the latter being in
the position of "danger."
Fig. 2 is a side view of the slide used in connection with the blade to change
colors and expose light.
Fig. 3 is a side of a signal post with the swinging arm lowered to "safety."
Fig. 4 is a top view of the signal arm and post.
Fig. 5 is a sectional view on the line a - - - - - b of Fig. 4.
Fig. 6 is a sectional view through the lamp holder and a portion of the supply
tube on line y -
- y of Fig. 4.
----
Fig. 6 is a sectional view of the oil reservoir on line x
x of Figure 4.
Fig. 7 is a side view of a signal arm with modified form of lamp, the arm being
in position of "danger."
"
Fig. 8 is a side view of the arm shown in Fig. 7 but lowered to position of
safety."
Fig. 9 is a top view of the arm or blade represented in Figures 7 and 8.
Figs. 10, 11 and 12 are detail views showing the modified form of lamp and
fittings.
The said invention may be carried into practical effect in a great variety of
ways and hence, in specifying the best methods and means for producing the
illumination of the signal blade or arm and controlling such illumination under
different conditions I do not wish to be understood as confining myself to any
special form or construction of blade or to any of the details in the mechanism
which I, by reference, employ.
I may take as the basis of my improvements, the semaphore devices now in use
on the principal railways, or I may construct special apparatus with a view to the
embodiment of the invention in the most practicable, economical and effective
shape.
°
The standard semaphore 'signal now in use on the lines of the Pennsylvania
Central Railway may be taken as a form of or construction of signal to which the
improvements are applicable, and such form is represented in the drawings,
particularly in Figs. 1, 3 and 4 wherein are shown the standard or usual casting A
which is pivoted to the signal post B and carries the disc B¹ on one end and the
blade or arm on the other end.
tc
For the purposes of this invention I substitute for the usual arm, which con-
sists of a strip of wood or metal, a hollow arm or casing C which corresponds in
length and width to the ordinary strip and generally resembles the same in
outline. If desired the front and rear walls of the hollow blade may converge
toward the outer extremity of the blade as shown in Fig. 4 so as to render the
blade light and less bulky. In the simplest form of an illuminated semaphore
blade the latter would consist of a casing having one or both sides made of glass
of any color with or without reflecting surfaces, while a lamp would be located at
one end and so arranged as to illuminate the interior of the blade and show its
character and position.
But I have elaborated this invention so as to comprehend other features and
thereby render the semaphore more perfect and better adapted to the purpose in
view. As shown in Figures 1, 3 and 4, for instance, I close one side of the hollow
blade and against or upon its inner surface, as at d, I arrange a reflector, such as
burnished metal, silvered glass or any other medium adapted to serve as a reflector
of light and I make such reflecting surface either plain, ribbed, fluted or other
shaped to produce the proper reflection and diffusion of the light for obtaining the
best effects.
О
The front of the hollow blade C, is formed with an elongated aperture approximating
in width and length the dimensions of the blade and in this opening or slot C¹ is
arranged the glass preferably in narrow strips vertically disposed as shown at d

page_text: not only to increase the stability of the glass but to provide a convenient and
serviceable means for changing the color of the light. A single pane of glass,
however, colored red and in stripes alternating with the colorless portion may be
employed.
The light to illuminate the signal is preferably an oil lamp, but gas, candles,
electricity or other mediums may be employed, such changes and adaptation being
made in the light fittings and appurtenances as circumstances may require, the
special character or disposition of the source of light not being a constituent part
of the invention, except as hereinafter particularly pointed out.
I have, however, shown two different methods or appliances for the convenient
and effective use of oil lamps, as such means of lighting are the most commonly
employed and the most serviceable for railway purposes. According to the plan
illustrated in Figs. 1, 2 and 4 I utilize the disc B¹ as an oil reservoir, making the
disc hollow and leading therefrom to the lamp a supply tube through which the
lamp is kept constantly supplied with oil. I locate the lamp lettered E, at the
inner end of the hollow blade in a suitable box or casing E¹ fitted between the
sides of the casting A or between the front and back walls of the hollow blade.
The lamp is suspended, by means of arms e, from trunnions e¹, e¹ having their
bearings in the casting A on a line coincident with the longitudinal centre of the
flame. The lamp therefore, hangs below the centre of the oscillation, and as its
casing E moves with the signal arm, the lamp remains in the one position, that
is with its wick tube and burner vertical. Thus there can be no overturning or
displacement of the lamp whatever by the action of the signal.
The supply tube F extends from the lower side or bottom of the reservoir B¹
and is bent upward at f, terminating at the end of the branch fin a sleeve which
encircles one of the trunnions e¹, e¹. The latter is formed with a passage e³ which
is in communication with an oil tube e located at the adjacent side of the lamp at
any suitable point near its bottom part. The arrangement of the oil supply tube
and reservoir in relation to the lamp is similar to that of the ordinary "student's
lamp," the lamp taking a fresh supply of oil whenever the oil in the lamp falls
below the inlet from the tube and allows the air to enter the supply tube and
pass into the reservoir.
A spring valve G is located in the reservoir and kept open by the closed cap H,
except when it is required to replenish the reservoir, the valve closing when the
cap is removed. The lamp and reservoir are always in the same relative position,
the passage way in the trunnion e¹ being always in communication with the supply
tube and with the tube e³.
In Figures 7, 8, 9, 10, 11 and 12 I show a modified form of lamp wherein the
latter is situated in a chamber or box formed upon the bearing or axial point of
the blade.
I designates such lamp, and the casing which incloses the same. The casing 22
is of prismatic form and is provided with a lid or cover by opening which
access is afforded to the lamp. The lamp is adapted to contain a supply of oil no
other or separate reservoir being required although such may be employed if
desired. The lamp is located at the bottom of the casing to which it is secured or
of which it may be a part and is adapted to move with the casing, the latter
moving with the signal arm. To compensate for this movement and allow the
lamp burner to remain in one position, that is upright or vertical, the burner is
made in two sections or parts h, h' pivoted together as shown, the upper part
carrying the wick tube.
.
Or the wick tube itself may be made in two parts hinged or jointed together as
shown in Fig. 10, the object being to allow the lamp to move independently of
the burner appliances. To maintain the burner in a vertical position I employ the
expedient shown in Figs. 11 and 12 wherein K designates a rod or wire forked
at one end as shown at k, so as to embrace the burner. This rod or wire is bent
down and passed into and through the hub L and fastened to a collar, which
encircles the hub at I¹; by means of a pin g passing through a slot r in the hub L

page_text: as shown. To this collar is attached another rod M which extends upwardly and
has its upper end bent over horizontally and inserted between the projections or
pins m attached to the signal post. Now when the lamp moves the rods K, M
being stationary and the burner held thereby, it is obvious that the lamp burner
will always remain in an upright position and at all times effectually diffuse its
light into and through the blade. Between the lamp and the cavity of the blade
in any construction within the spirit of this invention I may use lenses or other
devices for concentrating or modifying the light, and I may use for this purpose or
in addition thereto glass screens of any color so as to impart to the blade any color
required. The interposition of a transparent screen also serves to prevent the
products of combustion from entering the cavity of the blade, and in Figs. 4, 5, 7
and 9 and 10 I have shown a bull's-eye" lettered E' in position between the
lamp flame and the cavity of the blade.
With reference to the means for exhibiting different colored lights and for
effecting the transitions from one color to another so that the displayed color will
correspond with the position of the blade according as the indication is "danger."
"safety
or "caution" and in keeping with the conventional or arbitrary significa-
tion of the colors employed in railway signalling, let it be supposed that the strips
of glass in the blade are alternately, say red and colorless. At a distance corre-
sponding with the point of view under which the signal is observed, the appearance
while the light is shining through the red glass is that of uniform and unbroken
red. And hence the indication is "danger." Now to change the color from red to
white I employ a slide shown at N, Fig. 2 consisting of a frame containing strips of
colorless glass alternating with strips of opaque glass or other material or merely
strips of opaque material. The frame is adapted to slide upon or in suitable guides
and is in the position of a screen with reference to the "window" of the blade.
The strips in the slide correspond with those in the blade and when the latter is in
the position of "danger," that is horizontal, the colorless glass strips in the blade
are covered by the opaque strips in the slide, the light then shining through the
red glass. Thus it will be seen the position of the blade indicating "danger" is in
keeping with the color displayed which is also "danger."
When the slide is moved so as to uncover the colorless glass of the blade and
cover the red portions, the light displayed is white and the indication is "safety."
In order that the movement of the slide may be coincident with the movement of
the blade it is made to work automatically and by the following means. For the
purpose in view the slide is provided with a rod or arm n which is bent at its free
end so as to enter a slot n¹ in a plate or bracket O attached to the signal post
below the pivot of the blade.
This slot is of peculiar shape, being curved at its upper portion on a line concentric
with the axis of motion of the blade so that during the descent of the blade and
until the position of "safety" is reached there will be no movement of the slide
and hence the indication will be "danger," should it happen through any accident
that a complete fall of the blade should not take place or that the blade should
accidentally fall to nearly a "safety" position without a corresponding adjustment
of the switches or other devices of the road. No accident can therefore occur by
reason of the signal appliances failing to perform their functions since "danger" is
necessarily indicated under every condition except that of absolute "safety.”
Near its lower end the slot is extended horizontally and when the end of the
slide rod enters this portion of the slot the slide is suddenly moved, causing the
exposure or display of white light and the color indication of." safety." In practice
it will be advisable to have this movement of the slide take place suddenly and if
possible after actual safety is obtained, so that the indication of "safety" cannot
be given, unless there is positive "safety." This may be accomplished by allowing
the blade a little extra motion after a point of actual safety is reached.
At its lower extremity the slot may continue a short distance on a curve
concentric with the axis of motion of the blade as no further movement of the
slide will take place..
ر

page_text: In the reverse movement of the blade, that is from safety to "danger" the
arrangement above described produces a sudden and rapid change from "safety" to
danger" upon the slightest movement of the blade.
In this description. I have confined myself to indications under red and white
light, but I may employ the same devices substantially for displaying other colors
by a suitable modification of the blade and slide.
It is also within the spirit of this invention to display three or more colors or to
use colors for special signalling.
Having now particularly described and ascertained the nature of the said
invention, and in what manner the same is to be performed, as communicated to me
by my foreign correspondent, I declare that what I claim is :-
1 In a semaphore signal, a hollow or box-like signal arm or blade having its
side or face covered or closed by glass or other transparent medium in different
colors, substantially as described.
2nd In semaphore signals, a hollow or box-like swinging arm or blade having its
face or side covered or closed by glass in different colors, in combination with a
slide or screen by the movement or adjustment of which different colors may be
exposed, substantially as described.
3rd In semaphore signals, a hollow or box-like swinging arm or blade having its
face or side covered or closed by glass or other transparent medium in different
colors, in combination with a color changing slide or screen which will move
automatically and change the color of the exposed light to correspond with the
position of the arm or blade and indicate the same conditions, substantially as
described.
4th In semaphore signals, the combination with a hollow or box-like signal arm
or blade capable of artificial illumination and having one side covered or closed by
glass or other transparent medium, of a slide or sliding screen attached to said arm
and a slotted plate or bracket attached to the signal post and engaging an arm or
rod extending from the slide, whereby said slide will be automatically adjusted to
correspond with the position of the arm and to expose a colored light of the same
indication.
5th In semaphore signals, the combination with the artificially illuminated signal
arm and the slide by which the light is changed or its exposure governed, of a cam
plate or bracket connected to the slide and adapted to automatically move the
latter at the moment of actual "danger" or "safety," substantially as described.
6th In semaphore signals, a signal arm adapted to move in a vertical plane only
and upon a horizontal axis, said arm or blade being hollow or box-like in form and
having one of its sides or faces made of transparent material or provided with strips
or sections of transparent material, in combination with a lamp for illuminating
said blade in the direction of its length, and means substantially as described for
changing the color of the reflected beam of light, as set forth.
7th In an illuminated semaphore signal, the combination with a hollow box-like
swinging arm mounted upon and projecting from a hollow box or casing, of a lamp
located within said casing and constructed substantially as described, so as to cause
the light to adapt itself to the varying positions of the arm and maintain constantly
an upright position, said box or casing being located at the pivotal centre or point
of oscillation of the blade and coincident therewith, as set forth.
8th In an illuminated semaphore signal, the combination with a hollow box-like
swinging arm having an open end, of a lamp arranged at the open end of said arın
and a reflector arranged in a vertical plane or between the upper and lower sides
and lengthwise of the arm at an angle to its face, whereby the light from the lamp
is reflected through the transparent side of the arm, substantially as described.
9th In a semaphore signal, the combination with a hollow box-like swinging arm
and a lamp arranged at one end thereof, and adapted to light the interior of the
same, of a corrugated reflector arranged lengthwise of said arm, substantially as
described.

page_text: 10th An illuminated semaphore signal consisting essentially of a hollow wedge
shaped arm pivotally attached to a post or standard and having a glass window or
screen on its face or side and an interior reflecting surface opposed to said screen
and arranged so as to reflect the light from the lamp through said window or
transparent screen, in combination with a lamp located at the pivotal or axial point
of said blade and a casing enclosing said lamp, the interior of the casing and the
cavity of the arm being separated by a transparent screen or window which will
admit light to the arm in all positions of the latter, substantially as described.
11th In semaphore signals, the combination with a wedge shaped hollow arm
having a transparent side, of a suitably located lamp arranged and adapted to
illuminate said arm in all positions, said lamp being pivotally suspended and
said arm supported on a horizontal axis and adapted to oscillate in a vertical
plane only.