Improvements in Switch and Signal Mechanism.
Year: 1887

page_text: Date of Application, 13th Sept., 188
Specification Accepted, 23rd Dec:, 1887
Improvements in Switch and Signal Mechanism.
I, FRANK H. TREACY, of Poughkeepsie, in the County of Dutchess, and State
of New York, one of the United States of America, Machinest, 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 combined mechanism for operating switches, locking
devices, and signals, either simultaneously, or consecutively, and its object is to
simplify the construction, increase the accuracy and certainty of operation, and
consequently lessen the danger of accidents.
My invention consists of the combination in a suitable mechanism of means for
shifting the switch, of a compensating device, allowing an excess of movement in
certain parts, a locking mechanism, a detector bar and a pair of signalling devices
connected with said parts, and an intermediate mechanism between said signalling
devices and the operating parts aforesaid, whereby the signals will be moved only
either before or after the switch has been shifted.
My invention also consists in the combination with the operating parts of a switch
mechanism, of the movable rails, and a pair of semaphore blades, with a compensating
locking device between said operating parts and rails, and another compensating
device between said operating parts and said blades, the whole combined and arranged
in such a manner that when the rails are being moved, the blades will remain at rest
in a position to indicate "danger" and will not move to "safety" until after the rails
have been moved and locked.
My invention also consists in certain other combinations and arrangements of parts
as hereinafter described and particularly pointed out in the claims.
Referring to the accompanying drawings:
Figure 1 is a plan view of a section of track showing a switch provided with my
improved, shifting, locking and signalling devices, all the parts being in the
position they would occupy when the shifting of the switch has been half
accomplished.
Figure 2 is a side elevation showing the detector bars.
Hirosa and 2 b are views of detached details of my invention.

page_text: Figures 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, and 13 illustrate the signalling devices.
Similar letters refer to corresponding parts in all the views.
The track is composed of rails A, of the ordinary construction, the movable rails B,
constitute the well known "split" switch.
One or more of the ties C, are preferably larger than the rest, to afford convenient
support for certain parts of the switch mechanism constituting what may be called a
compensating movement which will now be described.
The rod a leads from a signal tower or other point (not shown) to the lever a³,
which is fulcrumed to a base plate fastened to a tie C. At its outer end the lever is
provided with a lug at which may, if desired, be provided with one or more anti-
friction rollers, while the other end of the lever may extend beyond the fulcrum, as
shown. Pivoted to the base plate, at a point a little in front of the fulcrum of lever a²
is a double faced and centrally notched cam a¹. When the lever a³ is moved, the
lug a engages with the notch a in the center of the cam a' and turns the cam upon
its pivot, but, as the lever is pivoted eccentrically to the cam, the radius of the arc
described by the lug a* is greater than that described by the notch in the cam, the
lug therefore soon leaves the notch and glides along one of the curved faces of the
cam, which extend each way from the notch. The curvature of these faces corresponds
with the arc described by the lug at so that the movement of the lug after it leaves
the notch does not turn the cam any further, but it does prevent the cam from turning
back again.
The cam will thus be turned a predetermined distance, and no more, irrespective
of the excess of travel of the lug at and thus constitute a compensating locking
movement, which has a fixed range of oscillation from one predetermined point to
another.
Moreover, the actuation of the cam is accomplished in a comparatively short interval,
and while the lug at is traversing a short portion of its arc.
To the cam a is pivoted one end of a short link connecting it with the switch
bar a³. The extent of oscillation of the cam, is of course so arranged as to be just
sufficient to shift the switch bar a³ and the movable rails B, from one position of the
switch to the other.
It will be seen that when one of the rails B, has been brought against the adjacent
rail A, the switch will be locked by the movement a, a', a³, a' since the lug a*, prevents
any backward turning of the cam.
But in order to relieve these parts of strain and shock, I provide a separate
locking mechanism, which is operated by the same motion of the rod as that which
actuates the switch.
The points of the movable rails B, are connected by a flat bar F¹ which is
provided with two perforations ff, and slides through a guide D fastened to one of
the ties.
In a tubular portion of the guide D is a sliding bolt F arranged at right angles to
the bar F. This bolt F is reciprocated by means of rod d³, bell crank lever d¹
and rod d.
It is obvious that it must not be thrown forward again until the rails B have come
to rest, and that this must be accomplished when the switch is shifted in either
direction. In order to effect this result, I locate a lever b¹ so as to be in line with
the rod d, when the bolt F is withdrawn, as shown in figure 1. It will be seen that
any movement of the lever either way from this central position will exert a
pull on the rod d, and throw the bolt F forward into engagement with one of the
perforations in the bar F. In order to move the lever 6' I connect it with the
lever a' by means of a rod b.
The motion of the lever a' before its lug at engages the cam a¹ will bring the
lever b¹, up towards its central position and withdraw the bolt F, leaving the
rails free to be shifted by the cam, while this is being effected, the lever 6' will reach
and pass its central position, and the further excess of travel of the lever a' will carry
the lever 6 far enough beyond said position to throw the bolt forward into its per-
foration f, in the bar F¹, which has already come to rest, when the motion of the

page_text: upper
cam a ceased. The same operation will ensue when the switch is shifted to the
opposite side. In connection with all these parts I employ a detector bar. This
detector bar E¹ is arranged alongside one of the rails A and is pivoted to the
ends of the several short parallel links e, the lower ends of which are pivoted to lugs
or ears on the flange of the rail A. The upper edge of the bar E' lies normally just
below the top of the rail. A rod E connects the detector bar with the lever a³,
When the
preferably with the extended rear end of said lever, as shown in Fig. 1.
lever is thrown from one side to the other, the detector bar E¹ will be raised, carried
lengthwise, and then lowered again, since the upper ends of the links e describe arcs
of small circles. When the detector bar is down and a train passes over the switch,
the wheels of the train prevent the detector bar from rising, and consequently prevents
the switch from being shifted, either accidentally, or intentionally until the train has
passed.
In order that the engineer of an approaching train may be apprised of the condition
of the switch I erect at any suitable spot a signal post G provided with two signalling
devices H, I, one for the main track and one for the siding. These may be semaphore
blades, as shown, or numbered disks, or any suitable devices for attracting attention.
Upon a stud g, projecting from the post G, are journaled two arms L, M, and a
lever K, the latter being between the two arms, as shown in Figure 13. The end
of the arm L is connected by a rod H¹ with the signalling device H: and the arm M
is similarly connected with the other signalling device I, by a rod I', the
arrangement being such that when the arm is raised, the signalling device will be
brought to "safety," but if the arm is allowed to fall, the signal will indicate
danger."
When the lever
The lever K is provided with two laterally projecting lugs k, k¹.
is swung to the right, as shown in Figures 3 and 6, the lug k comes in contact
with the arm Land raises it, bringing the signal H to "safety" and leaving the other
at "danger." When the lever is moved to the left as in Figs. 5 and 8, the signal I
is brought to safety and the signal H remains at danger. When the lever hangs
vertically as in Figs. 4 and 7 both signals stand at danger. In this position the
space between the arms Land M is such that the lever K must swing through a
certain are before either of the lugs k k¹ will strike its respective arm, so that
changing the signals from the position shown in Fig. 3 to that shown in Fig. 5 they
will, for a short time, both stand at danger, as shown in figure 4.
In order to swing the lever K, it is connected by means of rod c¹ bell crank lever c
and rod or other equivalent means, with lever br, or a² as may be most convenient.
The parts are so arranged and proportioned that when lever a begins to move and
the bolt F begins to be withdrawn the lever K commences to lower the arm which it
has been holding up, and the corresponding signalling device starts toward a position
to indicate danger. By the time the lug at in the lever a² engages with the cam a',
to shift the switch, the bolt F has been withdrawn from perforation f, in bar F¹ and
the signalling devices are both standing at danger, as in Fig. 4. While the cam a' is
shifting the switch the lever K is swinging across towards the other arm both signals
remaining at danger, and when the switch closes, and the lug a' leaves the notch, the
lever K strikes this other arm, and brings down to safety, the other signal, corre-
sponding to the track, which is clear.
It will be seen that both signals remain at danger until the switch rails have been
unlocked and moved and locked again by the lever and cam.
The arms K, L, M, also act in the capacity of a compensating device, in that they
allow an excess of movement of the rod c' without any material change in the relative
position of the semaphore blades.
It should be remarked that the detector bar is raised nearly to its highest point
before the cam a¹ is acted upon, and that in the descent its weight assists in moving
the various parts of the mechanism.
It is obvious that the several parts of this switch and signal mechanism, viz.; the
switch operating movement, the locking mechanism, the detector bar, and the
signalling devices, may be used separately, or in combination with other similar

page_text: apparatus for accomplishing their object. Furthermore, the precise arrangement of
lever and connection shown in the drawings may be more or less varied without
departing from the spirit of my invention.
Having thus described my invention what I claim and desire to secure by Letters
Patent is
1st. The combination with the rails B, of a pivoted double face cam a¹ located
adjacent to the switch, the lever a² having the lug a to engage with a notch in said
cam to turn it in either direction from a central position, and to lock the said cam
when so turned, the said cam being pivoted between the pivot of said lever and its
lug, a rod a connected with said lever to move the same, and a switch bar a³ pivoted
to the cam and connected with the rails B, whereby the rails will be moved when the
cam is turned, substantially as described.
2d. In a switch mechanism, the combination with the switch bar of a double faced
pivoted cam a¹ the lever a² having at one end a lug a to engage with said cam, the
other end of said lever being connected by rod E with the detector bar E¹ whereby
the detector bar will be lifted nearly to its highest point before the cam is actuated to
move the switch.
3d. The combination with the switch having the perforated locking bar F' of the
compensating locking movement a a', a², at, the rod b, lever b' and a bolt F actuated
to engage with the locking bar by a movement of lever b¹ in either direction from a
central position.
4th. The combination with a switch, having a perforated locking bar F¹, of the
compensating locking movement a, a', a², a', the rod 6, the lever b', the rod d, con-
nected with said lever b₁ so as to lie substantially in line therewith when the
lever is in its central position, the bell crank lever d' rod d² and bolt F, whereby
the bolt will be thrown forward by a movement of lever either way from a
central position.
5th. The combination with a switch, having perforated locking har F1 of a bolt F,
rod d² bell crank lever d', rod d and lever b' said rod and lever lying substantially in
the same line when the lever is in its central position, mechanism for operating
the switch, and connection between said mechanism and the lever, whereby said
lever will be moved from a point at one side of its central position to a point on
the other side whenever the switch is operated, whereby the bolt F will be first with-
drawn and then thrown forward again as the switch is operated.
6th. The combination in a switch mechanism of the compensating locking move-
ment a, a, a, a the locking mechanism b, b', d, d', d², F and F and the detector
bar E and rod E the rod 62, a two bladed semaphore and intermediate mechanism
actuated by said red, and only operative to change the position of the blades before
after the and switch is shifted.
7th. In a switch mechanism, the combination with the rod a, cam a¹ and lever a²,
of a locking mechanism and detector bar, operated simultaneously with said lever a³,
a signal post G, carrying two semaphore blades H I, a lever K having the projecting
lugs k, k, the arms L M pivoted concentrically with lever K, rods H₁, I', connecting
the blades H, I, with the arms L, M, and connection between the lever K and the
lever a².
8th. The combination with a switch, of the rod a, cam a¹, lever a², a signal post, a
lever K pivoted thereto and provided with lugs k k¹, suitable connection between
lever K and the lever a³, two arms L, M, pivoted concentrically with lever K,
signalling devices H, I, rods H³, 11, so that when the lever a² is first moved, both
signalling devices will come to "danger" and remain there until the lever a² has
shifted the switch, when the further movement of the lever will throw down one of the
signalling devices.
9th. In a switch mechanism, the combination with means for shifting the switch of
a single actuating rod a connected with a compensating device allowing an excess of
movement in certain parts, a locking mechanisin, a detector bar and a pair of sema-
phore blades connected with said parts, and an intermediate mechanism between said

page_text: semaphore blades and the operating parts aforesaid, whereby the blades will be moved
only either before or after the switch has been shifted, the parts being so arranged
and connected that a single movement of the actuating rod a will operate all the
several elements of the combination, substantially as shown and described.
10th. In a switch mechanism, the combination with a single actuating rod a, and
its co-operating parts, of the movable rails and a pair of signalling devices with
compensating locking device between said operating parts and rails, and another
compensating device between said operating parts and said signalling devices, the
whole combined and arranged in such a manner that when the rails are being
moved the signals will remain at rest in a position to indicate "danger" and will
not move to "safety" until after the rails have been moved and locked, the parts
being so arranged and connected that a single movement of the actuating rod a
will operate the several elements of the combination, substantially as shown and
described.
11th. The combination with the movable rails of a switch, of a compensating
locking movement a a', a³, a locking mechanism b, b, d, d¹, F, F a detector bar E
and rod E, rod 6 connected with a compensating device K, L, M, and signalling
devices H, I, the whole so arranged and combined that a single movement of rod a,
will unlock the switch, set both signals at "danger," operate the detector bar, and
lock the switch, and set one of the signals at "safety."
W. LLOYD WISE,
Per F. J. Brougham,
46, Lincoln's Inn Fields, London, W.C.,
Agent for the Applicant.