IMPROVEMENTS IN RAILWAY SWITCHES, AND IN SIGNALS AND OTHER APPURTENANCES THEREFOR."
Year: 1881

page_text: LETTERS PATENT to Alexander Elmer McDonald, of the City of New York,
in the State of New York, one of the United States of America, Mechanic,
for an Invention of "IMPROVEMENTS IN RAILWAY SWITCHES, AND IN SIGNALS
AND OTHER APPURTENANCES THEREFOR."
PROVISIONAL SPECIFICATION left by the said Alexander Elmer McDonald
at the Office of the Commissioners of Patents on the 12th March 1881.
ALEXANDER ELMER MCDONALD, of the City of New York, in the State of New
York, one of the United States of America, Mechanic. "IMPROVEMENTS IN
RAILWAY SWITCHES, AND IN SIGNALS AND OTHER APPURTENANCES THEREFOR.”
My Invention relates chiefly to "stub-switches," so called, wherein the end of
the main track is left free or unattached to the sleepers for some distance, so that
it can be moved opposite to and to coincide with the ends of either of the divergent
tracks. As ordinarily constructed switches of this character are frequently rendered
inoperative by the expansion of the rails, whereby the ends of the movable rails
are forced so tightly against the ends of the divergent rails that it is impossible to
shift them to any other position, and they are also injuriously affected by the con-
traction of the rails, which leaves a gap between the movable and the divergent
rails into which the wheels of passing trains drop, thus hammering down the
contiguous ends of the rails and injuring the rolling stock.
My Invention aims to obviate this and other disadvantages of the stub-switch,
and also to provide a lock therefor, which will prevent its displacement by
unauthorized persons, and to provide a signal which will indicate the exact position
of the switch to the engineer of an approaching train without the use of colors.
I place a metal bed plate beneath each movable rail, upon which said rail rests
and slides, and I extend one end of this plate beneath the ends of the divergent
rails, and fix the latter to it in such manner by bolts or otherwise that they cannot
move longitudinally upon it, and I extend the other end of the plate a short distance
beneath the fixed portion of the main track, and attach the rail thereof to it in
similar manner.

page_text: The expansion and contraction of this plate being nearly the same as that of the
movable rail keeps the fixed rails of the main and divergent tracks always at the
same distance apart relatively to the length of the movable portion of track, so
that the space between the end of the latter and the ends of the divergent rails
remains uniform. The expansion and contraction of the rails is thus forced to
expend itself at the rail joints remote from the switch, instead of in those at the
switch.
Instead of employing movable rails the exact length of the movable portion of
the track (usually about 20 feet), as has been done heretofore, I use rails of the
usual length (say, 30 feet), and fix the extra length thereof (say, 10 feet) to the
sleepers as part of the fixed main track, leaving their remaining portion free and
movable to form the movable portion of the track. I thus secure greater strength
in the latter portion of track than heretofore, and give it an easy curve when
deflected to either side.
The movable rails are connected together by transverse tie bars as usual, but I
prefer to form these bars with a shoulder near each end, and to thread the portion
beyond the shoulder. A slightly curved fish plate is placed on the outside of the
rail, with its convex side against the web of the rail;. the threaded end of the rod
is passed through coinciding holes in said web and plate, and a nut is screwed
thereon, clamping the rail and plate between the nut and shoulder. The shoulder
is preferably rounded slightly like the plate. The object of thus rounding the plate
and shoulder is to relieve the tie rod from strain when the movable portion of
track is shifted to either side of its straight position.
The switch is shifted as usual by a vertical shaft arranged at one side of the
track, provided at its lower end with a crank, which connects by a pitman to the
free end of the movable portion of track. A quarter turn of this shaft to either
side shifts the switch from one of the divergent tracks to the next. On the top of
the shaft is mounted a signal, which consists of a vertical arm with a wing or branch
projecting horizontally therefrom, preferably in L shape. When the switch is set
straight ahead this branch stands parallel with the track, so that the engineer of an
approaching train sees it in end view, in which case the signal appears to him as a
vertical streak, but if the switch be turned to either side then the branch stands at
right angles to the track, and points in the direction to which the switch is turned,
so that the engineer sees it in side view, and knows from its position to which side
the switch is set. For night use this signal is constructed as a lantern, and contains
a light.
My lock for the switch consists of a horizontal shaft extending under the
movable track near its free end, and provided with radially projecting ears which
pass up through slots in the base plates, and embrace the movable rails between
them if the switch be set straight ahead. Before the switch can be shifted these
ears must be turned down beneath the surface of the base plate by partially
revolving the horizontal shaft, and after shifting the switch they can be turned up
again by a backward movement of said shaft.
When the switch is turned to either side each movable rail is confined between
one of the ears and a fixed stop. The end of the horizontal shaft extends to near
the vertical shifting shaft, and bears a lever which when the ears are turned up
stands vertically and enters one of two or three notches formed in a disk borne by
the vertical shaft, being fastened in that position by a padlock or similar device.
The turning of the shifting shaft to shift the switch is thus prevented until the
handle has been turned down so as to depress the ears and unlock the switch. The
raising of the free end of the movable portion of track is prevented by a fixed
horizontal bar which crosses over the end tie-rod between the rails.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Alexander Elmer McDonald in the Great Seal Patent Office on the
10th September 1881.
ALEXANDER ELMER MODONALD, of the City of New York, in the State of New
York, one of the United States of America, Mechanic. "IMPROVEMENTS IN
RAILWAY SWITCHES, AND IN SIGNALS AND OTHER APPURTENANCES THEREFOR."
What are known as "stub-switches" on railways as ordinarily constructed have
several serious disadvantages, due chiefly to the expansion and contraction of the
rails. If the space between the switch rails and the fixed rails be made slight the
expansion of the rails jams the switch rail so firmly against the end of one of the
divergent fixed rails that it is impossible to shift the switch. Accidents and
detentions to trains have often resulted from this cause. On the other hand, if
sufficient space be left at the joint between the switch rail and the divergent fixed
rails to ensure the proper operation of the switch when the rails are expanded,
the rails when they contract draw so far away from each other as to leave &
considerable gap between them, so that the wheels of passing trains batter down
the ends of the rails and render the switch rough to pass over and injurious to the
rolling stock.
One object of my Invention is to obviate these objections and render a stub
switch free and safe in its operation and as durable and smooth to pass over as
any part of the roadway. Another object is to provide a means for securely
locking the switch in any position so as to prevent its displacement by unauthorized
persons; and the third object of my Invention is to provide a signal which shall
indicate to the engineer of an approaching train the exact position of the switch
without the use of colors or colored lights.
In the Drawings,—
Figure 1 is a plan of my Invention; Figure 2 is a side elevation thereof, and
Figure 3 is a vertical transverse section thereof taken in the plan of the line 3-3,
in Figure 1, and showing the signal in front elevation; Figure 4 is a plan of
portions of the switch; Figure 5 is a vertical longitudinal section thereof taken in
the plane of the line 5, 5, in Figure 4; Figure 6 is a side elevation of the signal
and a portion of the switch; Figures 7 and 8 are transverse sections of the rails
taken respectively in the planes of the lines 7, 7, and 8, 8, in Figures 4 and 5, and
showing details of construction; Figure 9 is a fragmentary horizontal section of
Figure 8; Figure 10 shows in side clevation and transverse section a modification
of Figure 8; and Figure 11 is a vertical mid section of the signal lantern.
Figures 4, 5, 6, and 10 are on a scale double that of Figures 1, 2, and 3; and
Figures 7, 8, 9, and 11 are on a scale four times that of Figures 1, 2, and 3.
A is the main or undivided track with fixed rails; B is the movable portion of
the track forming the switch, and C, C, are the divergent tracks with fixed rails,
one of which may be in practice the main or through line and the others branches
or sidings. I have shown three divergent tracks, but 2 or other number may
be used as circumstances dictate. The rails A and C are fixed to sleepers or
ties a, a, as usual. The rails forming the movable track B, which I shall refer to
as the switch rails, are fixed at their one ends, forming there a part of the main
track A, and are provided at their other ends with a shifting mechanism for
bringing them opposite either of the divergent rails C, C. The two switch rails
are tied together by the tie rods b, b. I have thus far described the usual form of
"stub switch."
D, D, are long flat plates which extend under the switch rails and afford a bed
for the latter to rest and slide on. They extend beyond the movable track B

page_text: under the rails of the track A and C, C, and are securely fastened thereto, so that
the rails of the tracks A and C are maintained at the same distance from each
other, and are not permitted to be drawn further apart by their contraction or
forced further together by their expansion, or by the traction of passing trains. Thus
the intermediate space is rendered substantially unchangeable, so that the movable 5
portion of track B may have free play therein. The plates D, D, are preferably
formed of metal, the extent of whose expansion and contraction is the same as or
similar to that of the rails B, B, so that the plates and rails shall expand and
contract together and in the same proportion, whereby the space between the free
end of the rails B and the approaching ends of the divergent rails C remains equal 1
and uniform at all times. "I prefer to make the rails B and plates D both of
steel.
The fixed rails of the tracks A and C are fastened firmly to the plates D in such
manner that they cannot move longitudinally thereon. Figures 5 and 7 show this
fastening, which consists of a bolt passed through a hole in the plate and a slot in 1
the base of the rail, and having a nut screwed on its end.
Figures 4, 5, 8, and 9 show the preferable form of the tie rods b, b. These
consist of rods having a convex shoulder formed at each end with a screw threaded
portion beyond the shoulder. This latter portion passes through a hole in the web
of the rail; a curved plate. is placed against the rail, the threaded end of the rod 2
passing through a hole in said plate, and a nut is screwed on its end, clamping the
rail and plate between this nut and the said shoulder, as best shown in Figures 8
and 9. The rail is thus clamped between two convex surfaces, so that in the
movement of the switch sufficient play is allowed not to strain the tie rod.
Figure 10 shows another form of tie rod, the end of which embraces the base of 2
the rail and slides in a groove formed across the top surface of the plate D, either
cut into said plate or made by crimping down a portion thereof, as shown. This
construction I consider inferior to that first described, because the formation of the
said groove weakens the plate D in its resistance to longitudinal strains.
Stub switches as heretofore constructed have had short rails for the movable 3
portion B of the track connected to the fixed rails of the track A by fish-joints
at c, so that when the switch is turned to one side or the other this rail moves
bodily from said joint, there being sufficient yield at the joint to permit the move-
ment of the rail. Thus the only connection of the movable rails is by the fish
joints and by the tie-rods b, b. In lieu of this I employ a long rail, leaving part of
it unattached to act as the movable rail B, and fixing the remainder of it so as to
serve as part of the fixed track A, as shown in Figures 1, 4, and 5. The elasticity
of the free part B of the rail permits it. to be bent to either side in shifting the
switch, thus forming an easy curve, and its connection is much stronger than is that
of a short rail applied as heretofore. The strain of bending the rail to either side
is resisted by the plate D.
E is a vertical shaft set in bearings at one side of the switch, terminating in a
crank e at its bottom, bearing a signal F on its top, and provided with a radial
arm or handle d. A connecting rod f communicates the motion of the crank to
the switch rails B. The Drawings show the switch set straight ahead, and the
handle d and crank e standing parallel with the track. A quarter turn of the
shaft E bringing the handle and crank at right angles to the track, shifts
the switch to one side or the other. The signal F turns with the shaft and appears
of different shape when seen from either side than when seen from in front. I
have shown it as of L.shape in side view, as illustrated in Figures 2 and 6, and
of shape in front or rear view, as shewn in Figure 3. It consists of a vertical
part g and a substantially horizontal part / projecting therefrom in a direction
parallel to the handle d. The engineer of an approaching train sees it in the
direction of the view in Figure 3, and its apparent shape indicates to him the
position of the switch. If the switch is set straight ahead or to the main track the
signal appears of I shape, as shown in full lines in Figure 3, but if the switch is
turned to either side the signal appears of L shape, with the part 7 turned in the

page_text: direction to which the switch is set. For night use the signal F is made a lantern
as best shown in Figure 11, wherein i is the metal casing, k, k, are the glass panes,
and Z is the lamp. The signal need not be L shaped, as other suitable forms may
be devised, the essential being that the apparent form of the signal as seen from an
approaching train shall indicate whether the switch be turned, and if so to which
side.
'I provide a lock for the switch rails which effectually prevents the shifting of
the switch by any unauthorized person. G is a shaft which extends under the
switch rails at right angles to the track, is hung in bearings so as to be free to
oscillate, bears two pairs of ears m, m, and is provided with a handle or lever H by
which to oscillate it. The handle H is placed at or near the switch shifting shaft E,
and the ears m, m, are arranged under the switch rails, one pair under each rail, so
that when elevated by the oscillation of the shaft they will embrace between them
the base of each switch rail if the latter be in its central position, thus holding it
in that position, or if it be shifted to either side the one on that side will prevent
its return, its base being then confined between that ear and the fixed stop n.
When the ears are elevated the handle H stands vertically. The shaft E bears a
disk s having 3 notches r, r, one of which the handle H enters when elevated, thus
preventing the turning of the shaft E. A projection o on the frame bearing the
shaft E enters a socket in the handle H, and its end receives a padlock p (Figure 6),
thus locking the handle H in place. The switch cannot be shifted until this handle
is turned down in the position shown in dotted lines in Figure 2, thus freeing both
the shaft E and the rails B, B. The ears m, m, work in slots in the plate D.
A bar q extends across the tie rod b at the free end of the switch track B to
provent evil disposed persons from lifting the free ends of the switch rails over the
ears m, m.
Having now fully described and ascertained the nature of the said Invention,
I declare that I claim,-
First. Providing a stub switch with the base plates to which the ends of tho
divergent rails and the fixed portions of the switch rails are fastened, in the
manner and for the purposes, substantially as hereinbefore set forth.
Second. Fastening the prolonged ends of the movable rails of the switch to base
plates, extending under them in such manner that the strain of springing the rails
to either side in shifting the switch is resisted by the base plates, substantially.
as set forth.
Third. The method of connecting the tie bars b, b, to the switch rails shown in
Figures 8 and 9, substantially as herein described.
Fourth. The signal for switchos herein shown and described, whereby the engineer
can know the position of the switch by the shape of the signal and without
reference to the color.
Fifth. The locking devices for retaining the rails in place, and preventing their
being shifted by unauthorized persons, substantially as set forth and shown.
In witness whereof, I, the said Alexander Elmer McDonald, have hereunto set
my hand and seal, this Twelfth day of August, in the year of our Lord
1881.
ALEXANDER ELMER MODONALD. (LS.)