An Improved Method of Controlling or Interlocking Points or Switches on Railways.
Year: 1889

page_text: Date of Application, 26th Feb., 1889
Complete Specification Left, 26th Nov., 1889-Accepted, 26th Feb., 1890
PROVISIONAL SPECIFICATION.
An Improved Method of Controlling or Interlocking Points or
Switches on Railways.
I PAUL PRINCE of the Midland Railway Company, Derby, Signal Engineer do
hereby declare the nature of this invention to be as follows:-
The object of this invention is to properly control points or switches on Railways
that are too far from a signal box to be worked therefrom in the usual way. A
special advantage in the system about to be explained is that the controlling
apparatus is in the same frame as the lever that works the points and can be
combined if desirable with any other locking in the frame.
The mode is as follows:-By my improvements the disc or tablet (which is brought
by the train that is to use the points) has to be placed in a recess which is provided
in the point lever frame for that purpose and corresponding in shape and depth with
the metal disc or tablet. A lid or cover is provided for the recess which is attached
above the locking frame also a sliding bolt which is fixed in the frame below the
tablet recess and which is operated by the lever or catch rod of the lever working
the points.
1
Under one arrangement this connection is effected by mounting a transverse bridge
bolt having projections or wards to be intercepted by the action caused by the
tablet being placed into its proper or working position in its recess in the frame.
The bridge piece is carried in bearing slides and performs the bolting or locking of
vertical forks attached to the tablet lid. Or this locking and function of the tablet
could be effected by wedge and tappet locking carried in a suitable frame attached
to the lever or the catch rod of the lever. In order to secure safe working and
prevent tampering the lid is hinged on two parallel rods so as to cause a vertical
motion to the lid, and projecting downwards from the lid are two prongs or forks
in each of which is a hole at a fixed point from the underside of the lid and unless
the tablet is of a certain thickness so as to allow the lid to drop to a fixed point the
sliding bolt operated by the point lever or the catch rod of the point lever fixed
below the tablet recess cannot enter the holes in the forks or prongs and consequently
the points still remain locked. During the time the tablet is in its fixed position
within the recess by shifting the then unlocked hand lever the points may be moved
to any position, but before the tablet can be removed the points must be placed for
the main line as they were before the arrival of the train. The tablet has perforations,
grooves and slots in its periphery and may have projections at various points which
must fit exactly into the corresponding perforations or projections both in the frame
in which it is recessed and also in the lid which falls upon it. In the underside of
the lid I provide one or more special lugs or projections which shall pass through
a recess or recesses in the tablet or disc and into a corresponding recess or recesses
in the frame.
By another arrangement of my improvements, instead of placing the tablet or dis
in a horizontal recess with its lid working vertically I would arrange for such tablet
or disc to be pressed in or through a vertical slot having lugs or projections at
required places to give releasing action to the cross interlocking bolt. In this
arrangement I would provide the same with a lid or cover hinged or fulcrumed at
one side or end or it may be driven in parallel grooves so that when such lid or cover
is completely home with the tablet or disc in its slot the operating lever or catch
rod of the points will then be free to move the points or switches and the lid and
tablet or disc cannot be interfered with until the points are set for the main line.
Dated this 26th day of February 1889.

page_text: COMPLETE SPECIFICATION.
An Improved Method of Controlling or Interlocking Points or
Switches on Railways.
I PAUL PRINCE of the Midland Railway Company Derby, Signal Engineer 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:-
The object of this invention is to properly control points or switches on Railways
that are too far from a signal box to be worked therefrom in the usual way. A
special advantage in the system about to be explained is that the controlling
apparatus is in the same frame as the lever that works the points and can be combined
if desirable with any other locking in the frame. And in order that my said
Invention and the manner of performing or carrying the same into effect or practice
may be properly understood I have hereunto appended two explanatory sheets of
Drawings, in which the same reference letters are used to indicate corresponding
parts in all the Figures where shown.
Figure on Sheet 1 is a vertical sectional view of my new or improved device, or
arrangement and combination of mechanism for controlling or interlocking points or
switches on Railways showing the lid or cover b in its down position with the tablet a
in its position releasing the switch operating lever B. B'.
Figure 2 is a view corresponding to Figure 1. showing the lid or cover ↳ as lifted
up ready to receive the tablet a.
Figure 3 is a top or plan view of one form of tablet a.
Figure 4 on Sheet 2 is a corresponding vertical section to Figure 1 of a modified
arrangement of my Improvements specially adapted for being operated by the lever
itself B, or connections therefrom; and Figure 5 is a plan view corresponding to
Figure 4.
Referring to Figures 1 to 3 of these Drawings
By my Improvements the disc or tablet a (which is brought by the train or engine
that is to use the points) has to be placed in a recess at a¹ which is provided in the
ordinary point lever frame A or attachment thereto for that purpose, and corresponding
in shape and depth with the metal disc or tablet a.
A lid or cover b is provided for fitting into and over the recess a¹ and is secured
to work in parallel guides or fulcrums as will hereinafter be described above the
frame A.
A sliding bolt or bridge piece is also fixed in the frame A at c below the tablet
recess a¹, and is operated by the rocking shaft d actuated by the switch operating
lever B or catch rod B' of this lever working the points.
Under one arrangement as shown in these Figures 1 to 3 this is effected by
mounting a transverse bridge bolt or plunger at c', at right angles to the bridge
piece e fitted with a spiral or other recoiling spring and having projections or wards
to be intercepted by the action caused by the tablet a being placed into its proper or
working position in its recess a¹ in the frame A. The bridge bolt c is carried in
bearing slides and perforins the bolting or locking of vertical forks or prongs e
formed on or attached at their upper ends to each side of the tablet lid b. Or as
shown in Figures 4 and 5 this locking and function of the tablet a can be effected
by wedge and tappet or slot and stud locking carried in a suitable frame or bearings
attached to the lever B or the catch rod B of the lever B or connections therefrom.
In this arrangement Figures 4 and 5, the bridge bolt c and locking lever_d are
dispensed with, and a direct sliding transverse bolt c¹ substituted therefor. In this
case the transverse spring, bridge, bolt c¹ operates a sliding bolt c2 in its tappet locking
slides c by a fixed pin and thimble in the bolt working in a slot in the outer
end of the lever plate c'. The one end c³ of the sliding bolt c works through a slot c*
in the slotted tappet arm d' which is substituted for the rocking shaft d in the former
C

page_text: arrangement, and by this motion the sliding bolt c also working in its guide casing cl
which is equivalent to the sliding bridge bolt c in the former arrangement Figs. 1
and 2 shoots through or interlocks the prongs e and so locks the tablet a in its fixed
or working position.
These
In order to secure safe working and prevent tampering, the vertical spindle 61
of the lid 6 is hinged or fulcrumed on two fulcrum parallel moving rods 6" secured at
their other ends to a vertical fixed standard 62 bolted or secured to the frame A, so as
to give a vertical or perpendicular motion to the lid 6 and its two prongs e.
prongs e are each formed with a hole or slot e¹ at a fixed distance from the underside
of the lid b, so as to allow this lid 6 to drop to a fixed point or position to enable the
sliding bolt c operated by the point lever B or lever catch rod B₁ to enter these
holes e¹ in the prongs e and so lock the tablet a in its recess a¹, and thus release the
lever B for performing its function of operating the switches.
During the time the tablet a is in its fixed position within the recess a² by shifting
the then unlocked hand lever B or B' the switch points may be moved to and fro for
shunting purposes and consequently the tablet a cannot be removed from its locked
position until the lever B or B¹ is returned to the original or normal safety position
in which it was before the arrival of the train.
The tablet a has perforations, grooves or slots formed through it such as at a² or it
may be projections, to fit into corresponding projections or perforations in the
recessed part a¹ of the frame A and also in the under part 63 of the lid or cover b
which falls upon same, and thus avoid any tampering with the mechanism by malicious
persons.
Instead of operating the bridge bolt c by a rocking shaft d as herein before
described this can be effected by a bell-crank or slotted bell-crank or eccentric
actuated by the operating lever B or B¹.
By another arrangement of my Improvements, instead of placing the tablet or disc a
in a horizontal recess a¹ with its lid b working vertically, I arrange for such tablet a
to be pressed in or through a vertical slot having lugs or projections at required
places to give releasing action to the cross interlocking bolt c.
In this arrangement I provide a lid or cover such as b hinged or fulcrumed at one
side or end, or it may be driven or pressed in parallel grooves so that when such lid
or cover b is completely home with the tablet a in its recess a¹ the operating lever B
or catch rod B³ of the points will then be free to move the points or switches, and the
lid and tablet a will then be locked as before described.
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 method, or arrangement and combination of mechanisms for controlling
or interlocking points or switches on Railways, substantially as herein described and
distinguished in reference to Figures 1 and 2, and 4 and 5, respectively of the
accompanying Drawings.
Second. In a device or mechanism for controlling or interlocking points or switches
on Railways the construction and use of a bridge bolt or equivalent sliding piece c for
interlocking a lid which covers a tablet recess, substantially as and in the manner
herein described in reference to and shown in the accompanying Drawings.
Third. In a device or mechanism for controlling or interlocking points or switches
on Railways the construction and use of a tablet recess. moving cover or lid having a
lug or projection formed on its under or inner surface so as to pierce into or through
the portable tablet when placed in position substantially as herein described in
reference to and shown in the accompanying Drawings.
Fourth. In a device or mechanism for controlling or interlocking points or switches
on Railways the construction of a parallel acting tablet recess cover or lid having
prongs, flanges, or projections with a slot or slots to receive an interlocking bolt,
substantially as herein described and shown in the accompanying Drawings.

page_text: Fifth. In a device or mechanism for controlling or interlocking points or switches
on railways the construction and use of a wedge and tappet or slot and stud locking
and releasing mechanism in conibination with a tablet working device actuated from
a lever or catch rod of lever or connections therefrom, substantially as herein described
in reference to Figures 4 and 5, of the accompanying Drawings.
Dated this 25th day of November 1889.
PAUL PRINCE.