Improvements in Railway Signal Lamps and Appliances Connected therewith.
Year: 1885

page_text: PROVISIONAL SPECIFICATION.
Improvements in Railway Signal Lamps and Appliances
Connected therewith.
I SAMUEL TELFORD DUTTON of No 1 Saint Georges Square in the City of
Worcester Civil Engineer do hereby declare the nature of the said Invention for
IMPROVEMENTS IN RAILWAY SIGNAL LAMPS AND APPLIANCES CONNECTED THERE-
WITH" to be as follows:-
My invention has for its object so to construct arrange and work the parts of
distant signal lamps situated at or near railway stations that at night the said
lamps shall present an appearance different from that presented by the home and
starting signal lamps the said distant signal lamps being made preferably to show
a luminous figure or image resembling the end of the signal arm the said luminous
image changing position as the end of the signal arm changes position. The
attention of the driver of a train is thus more vividly called to the distant signal
than when the lamp of the said signal resembles the lamps of the home and
starting signals.
I make the lens in front of the lamp of a series of concentric prismatic zones
either circular or nearly elliptical in outline. On one side of the lens 1 cut away a
sector having about the same angle as the cut away part at the end of the arm of
the signal. The frame carrying the lens is capable of rotating through an angle of
ninety degrees so that the middle line of the cut away sector may either be brought
horizontal or vertical. The frame carrying the lens is geared to the distant signal
so that it shall move with it the cut away sector of the lens always having the
Thus when the arm
same position as the angular cut away end of the signal arm.
of the signal is in a horizontal or danger position the cut away sector of the lens is
in the same position as the cut away end of the arm of the signal and when the
arm of the signal is in its depressed or all right position the cut away sector of the
lens is in the same position as the cut away end of the signal arm.
The luminous image presented by the lamp thus corresponds with the position
of the cut away part of the arm of the signal. The usual means are adopted for
giving colours to the luminous image of the lamp. Instead of cutting away a
sector of the lens as described a lens without the said cut away portion may be

page_text: employed. In this case a portion of the lens corresponding to the sector described
may be blackened or made opaque.
In cases where a lens is not used the front glass of the lamp may be roughened
or made semi transparent and have a black or opaque sector upon it. The glass in
this case has the motion herein before described with respect to a lens. The semi
transparent glass may be used in conjunction with a lens.
Where the moveable glasses called spectacles are used the sector may be painted
or otherwise made on the glasses of the spectacles so that when the said glasses are
moved by the signal in front of the lamp they shall produce the required form of
light in its two positions.

page_text: COMPLEIE DIECIFICATION.
"
Improvements in Railway Signal Lamps and Appliances
Connected therewith.
I SAMUEL TELFORD DUTTON of N° 1 Saint George's Square in the City of
Worcester, Civil Engineer do hereby declare the nature of my Invention for
IMPROVEMENTS IN RAILWAY SIGNAL LAMPS AND APPLIANCES CONNECTED THERE-
WITH" 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 object so to construct, arrange and work the parts of
distant signal lamps situated at or near railway stations that at night the said
lamps. shall present an appearance different from that presented by the home and
starting signal lamps, the said distant signal lamps being made preferably to show
a luminous figure or image resembling the end of the signal arm the said luminous
image changing position as the end of the signal arm changes position. The
attention of the driver of a train is thus more vividly called to the distant signal
than when the lamp of the said signal resembles the lamps of the home and
starting signals.
I make the lens in front of the lamp of a series of concentric prismatic zones
either circular or nearly elliptical in outline.
On one side of the lens I cut away a sector having about the same angle as the
cut away part at the end of the arm of the signal. The frame carrying the lens is
capable of rotating through an angle of ninety degrees so that the middle line of
the cut away sector may either be brought horizontal or vertical. The frame
carrying the lens is geared to the distant signal so that it shall move with it, the
the cut away sector of the lens always having the same position as the angular cut
away end of the signal arm. Thus, when the arm of the signal is in a horizontal
or danger position the cut away sector of the lens is in the same position as the cut
away end of the arm of the signal and when the arm of the signal is in its depressed
or all right position the cut away sector of the lens is in the same position as the
cut away end of the signal arm.
The luminous image presented by the lamp thus corresponds with the position
of the cut away part of the arm of the signal. The usual means are adopted for
giving colours to the luminous image of the lamp.
Instead of cutting away a sector of the lens as described, a lens without the said
cut away portion may be employed. In this case a portion of the lens corresponding
to the sector described may be blackened or made opaque.
In cases where a lens is not used the front glass of the lamp may be roughened
or made semi transparent and have a black or opaque sector upon it. The glass in
The semi
this case has the motion herein before described with respect to a lens.
transparent glass may be used in conjunction with a lens.
Where the moveable glasses called spectacles are used, the sector may be painted
or otherwise made on the glasses of the spectacles so that when the said glasse3

page_text: are moved by the signal in front of the lamp they shall produce the required form
of light in its two positions.
I will now proceed to describe with reference to the accompanying Drawing the
manner in which my invention is to be performed.
Figures 1 and 2 represent elevations of a railway signal lamp and appliances
constructed according to my invention in combination with a railway distant
signal arm. In Figure 1 the distant signal arm is shown at danger, the rotating
lens of the lamp being in a corresponding position to the cut away end of the
signal arm, the coloured spectacles being situated in front of the signal lamp. In
Figure 2 the distant signal arm is represented at the all right position and the
rotating lens in a corresponding position thereto.
Figures 3, 4 and 5 represent the railway signal lamp separately drawn to a
larger scale than in Figures 1 and 2, Figure 3 representing a vertical section of the
lamp; Figure 4 a front elevation of the same with the rotating lens at the danger
position and Figure 5 a front elevation of the same with the rotating lens at the
all right position; e is the rotating lens in front of the lamp made of a series of
concentric prismatic zones and e² is the sector like portion cut from one side of the
said lens, the said cut away portion e' corresponding in figure with the cut away
end c of the arm a of the signal (see Figures 1 and 2); f is a disc or frame carrying
the lense the said disc or frame rotating upon the centre g on the frame h fixed to
the lamp body (see Figure 3). For convenience of manufacture I prefer to make
the lens in two pieces which are fixed to the rotating disc or frame f. The said
disc or frame f carrying the lens is capable of motion through an angle of ninety
degrees as represented in Figures 4 and 5. When the rotating lens e is in the
position Figure 4 its cut away part e² is horizontal and when the said rotating lens
is in the position Figure 5 the cut away part e' is vertical. Jointed to the frame f
carrying the lens is a connecting rod i which gives motion to the said frame from
the signal arm or from a crank on the axis of the signal arm or from the signal rod
which works the signal arm.
The manner in which my improved railway signal lamp and appliances are
used is illustrated in Figures 1 and 2, where a is the distant signal arm; c the
cut away end of the signal arm; b the rotating lens of the lamp; the con-
necting rod jointed to a crank on the axis of the signal arm a; k is the rod by
which the signal arm a is worked and d is the coloured spectacles carried by the
signal arm.
It will be seen that when the distant signal arm a is at danger or in a horizontal
position, as represented in Figure 1, the cut away part of the lens bis in a corre-
sponding position to the cut away end c of the arm a the coloured spectacles &
being in front of the lamp and exhibiting a luminous image resembling the end of
the signal arm a.
When the signal arm a is in its depressed or all right position, the cut away part
of the lens is in the same position as the cut away end of the depressed signal
arm a as represented in Figure 2.
By making the lamp show a luminous figure or image resembling the end of the
signal arm the said luminous figure or image, changing position as the end of the
signal arm changes position, the attention of the driver of a train is more vividly
called to the distant signal than when the lamp of the signal resembles the lamps
of the home and starting signals.
The form of the rotating lens may be modified in the manner represented in
elevation in Figures 6 and 7, Figure 6 representing the position of the rotating lens
when the signal arm is in the depressed or all right position and Figure 7 repre-
senting the position of the rotating lens when the signal arm is in the horizontal
or danger position.
Figure 8 represents in front elevation and Figure 9 in vertical section taken on
the line l, m Figure 8 a railway signal lamp constructed according to my invention
in which the lens is incapable of rotation,

page_text: Lamps having the lens fixed may be used in special cases such for example as
when the lamp is hoisted up the signal post.
The lens represented in Figure 8 is made up of nearly elliptical zones but it
must be understood that a lens with circular zones or with elliptical zones may be
used in any of the lamps described and represented.
Figures 10 and 11 represent elevations of a distant signal arm and its lamp in
which Figures the moveable glasses called spectacles are used to exhibit the
luminous image of the end of the signal arm, the rotating lens or the rotating front
glass of the lamp being dispensed with.
The spectacle frame is marked n in the drawing and has two sector like glasses
n², n³ inserted in it, the one marked n being red and the other marked n³ being
colourless. The upper glass n² of the spectacles is brought opposite the lamp when
the signal arm a is in its horizontal or danger position as represented in Figure 11
and the lower glass n³ of the spectacles is brought opposite the lamp when the
signal arm a is in its depressed or out of danger position as represented in
Figure 10. In this way a luminous image resembling and in the same position
as the cut away end c of the signal arm is shown upon the spectacles in its two
positions.
Instead of the angular glasses n³, n³ circular glasses may be inserted in the
spectacle frame n and the sectors be painted on the glasses with black paint.
Although I prefer to cut away a portion of the lens in the form of a sector yet
cut away parts of other forms may be used and instead of cutting away a portion
of the lens, the lens may be without a cut away part and a portion of the lens
corresponding to the sector or the other form of luminous image to be produced
may be blackened or made opaque. Or the front glass of the lamp may be made
capable of motion similar to the rotating lens herein before described and have a
black or opaque sector made or painted upon it the position of the rotating front
glass corresponding with the changing position of the signal arm as described with
respect to a rotating lens. The rotating front glass last described may be used
with a lamp having no lens. In this case the rotating glass is roughened so as to
exhibit a luminous disc having an opaque sector upon it; the central part of the
front glass or lens may be clear glass and the surrounding parts and extremities
may be roughened.
Or the front glass of the lamp having the black or opaque sector may be fixed
and the lamp be used in place of the lamp having a fixed lens as represented in
Figures 8 and 9.
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
I claim as my invention of "Improvements in railway signal lamps and appliances
connected therewith "
First. Forming the lenses of distant railway signal lamps with an angular or
other shaped cut away part or with a blackened or opaque part corresponding in
shape with the end of the distant signal arm for the purpose of causing the lamp
to exhibit a luminous figure or image resembling the said end of the signal arm,
or its distinguishing feature, substantially as hereinbefore described and illustrated
in the accompanying Drawing.
Secondly. Making the lenses claimed in the previous claim capable of rotating
and gearing them with the signal arms, or the connecting rods by which the
signal arms are worked, in such a manner that the rotating lenses change their
positions as the signal arms change their positions substantially as herein before
described and illustrated in the accompanying Drawing.
Thirdly. Making the front glass of the distant railway signal lamp capable of
rotation and providing it with a blackened or opaque sector or other shaped part,
with or without a roughened or deadened surface, substantially as bereinbefore

page_text: described; also the application of the blackened or opaque sector or other shaped
part to the front glass when incapable of rotation as herein before described.
Lastly. Painting on or otherwise making in the moveable glasses called
spectacles used in front of distant railway signal lamps, black or opaque sectors
or other shaped parts so that when the said spectacles are moved by the signal
arm in front of the lamp they shall exhibit a luminous image of the end of the
signal arm in its two positions, coloured in the danger position and colourless in
the all right position, substantially as herein before described and illustrated in the
accompanying drawing.
D
1
Cth dose of December 1885