Improvements in Apparatus for Working Railway Points and Signals by Electricity.
Year: 1899

page_text: Date of Application, 20th Mar., 1899
Complete Specification Left, 13th Dec., 1899-Accepted, 27th Jan., 1900
PROVISIONAL SPECIFICATION.
Improvements in Apparatus for Working Railway Points and
Signals by Electricity.
We, FRANCIS WILLIAM WEBB, of Chester Place, Crewe, in the County of
Chester, Mechanical Engineer, and ARTHUR MOORE THOMPSON, of Holly Bank,
Crewe, aforesaid, Mechanical Engineer, do hereby declare the nature of this
invention to be as follows:-
In the Specification of Letters Patent No. 12128 dated 17th May A.D. 1897
granted to us are described an arrangement of an electric motor, worm, and worm
wheel and cam wheel for working points and other combinations and improve-
ments in apparatus for working railway points and signals by electricity. The
object of our present invention is to provide an improved apparatus for actuating
points more especially points to sidings over which shunting is performed and
requiring quick movement and the avoidance of damage to the points and the
actuating apparatus should the points be run through.
According to our invention we accomplish this by actuating the points by
means of an electro-magnet, or electro-magnets, the points being locked in
position by means of a bolt, or locking device, also actuated by an electro-magnet,
or electro-magnets. In the case of points such as siding points, the bolt, or
locking device, is of wedge form and so arranged that if the points be run through,
or great strain be otherwise thrown on them, the bolt, or locking device, will be
forced out and the points unlocked so that they can move to allow of the passage
of the flanges of the wheels.
In cases where the points are not required to be automatically unlocked as
aforesaid, for instance, in the case of points on the main line, the bolt, or locking
device, is not of wedge form and the bolt, or locking device, will
not be removed when strain is brought on the points. In combination
with the electro-magnets for actuating the points and the bolt, or locking device
we arrange certain electric switches so that if the points be not in position and
securely locked the lever movement in the cabin, such as is described in the
Specification of the aforesaid Letters Patent No. 12128 for example, cannot
be completed and we also provide switches actuated by the point movement so
as to prevent the actuation of a signal when the points are not in the proper
position for the signal to be taken off. When an electric current is passed
through the armature of an electric motor used for working points a large
volume of current passes through the armature coils until the armature begins
to revolve and then the current is rapidly reduced in volume. If the armature
should fail to move, or if, after being set in motion, it should be brought to a
stand the large volume of electric current which would then pass through the
armature would quickly damage or destroy it.
To avoid this we provide a cut-out so adjusted that it will cut out with a pre-
determined current above the ordinary working current, and, to prevent this
cut-out being actuated by the large current which passes just before the arma-
ture begins to move, we pass a shunt current through an electro-magnet the

page_text: armature of which is so connected with the cut-out that, when the electro-magnet
is energised the armature holds the cut-out in position. The shunt current is
only passed through the magnet coil for a very short time, and, to prevent the
armature returning to its normal position too quickly, we provide a damping
device; such, for example, as a dash-pot, in connection with the electro-magnet
armature which prevents it from too quickly moving back to the normal position
and releasing the cut-out when the shunt current is cut off, the dash-pot or the
like, being so arranged that the time taken by the magnet armature to regain
its normal position is considerably greater than the time during which the large
volume of current passes through the armature coils of the electric motor prior
to the armature revolving and so cutting down the current to its working
volume.
Dated this 20th dov of March 1800
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C.,, A Agents.
Improvements in Apparatus for Working Raiiway Points and
Signals by Electricity.
We, FRANCIS WILLIAM WEBB, of Coventry Place, Crewe, in the County of
Chester, Mechanical Engineer, and ARTHUR MOORE THOMPSON, of Holly Bank,
Crewe, aforesaid, Mechanical 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:-
In the Specification of Letters Patent No. 12128 dated 17th May A.D). 1897
granted to us are described an arrangement of an electric motor, worm, and worm
wheel, and cam wheel, for working points and other combinations and improve-
ments in apparatus for working railway points and signals by electricity. The
object of our present invention is to provide an improved apparatus for actuating
points, more especially points to sidings over which shunting is performed and
requiring quick movement and the avoidance of damage to the points and the
actuating apparatus should the points be run through.
According to our invention we accomplish this by actuating the points by
means of an electro-magnet, or electro-magnets, the points being locked in
position by means of a bolt, or locking device, also actuated by an electro-magnet,
or electro-magnets. In the case of points such as siding points, the bolt, or
locking device, is of wedge form and so arranged that if the points be run through,
or great strain be otherwise thrown on them, the bolt, or locking device, will be
forced out and the points unlocked so that they can move to allow of the passage
of the flanges of the wheels.
In cases where the points are not required to be automatically unlocked as
aforesaid, for instance, in the case of points on the main line, the bolt, or locking
device, is not of wedge form and the bolt, or locking device, will
not be removed when strain is brought on the points.
In combination
with the electro-magnets for actuating the points and the bolt, or locking-device,
we arrange certain electric switches so that if the points be not in position and
securely locked the lever movement in the cabin, such as is described in the
Specification of the aforesaid Letters Patent No. 121287 for example, cannot
be completed and we also provide switches actuated by the point movement so
as to prevent the actuation of a signal when the points are not in the proper

page_text: position for the signal to be taken off. When an electric current is passed
through the armature of an electric motor used for working points a large
volume of current passes through the armature coils until the armature begins
to revolve and then the current is rapidly reduced in volume. If the armature
should fail to move, or if, after being set in motion, it should be brought to a
stand the large volume of electric current which would then pass through the
armature would quickly damage, or destroy, it.
To avoid this we provide a cut-out so adjusted that it will cut out with a pre-
determined current above the ordinary working current, and, to prevent this
cut-out being actuated by the large current which passes just before the arma-
ture begins to move, we pass a shunt current through an electro-magnet the
armature of which is so connected with the cut-out that, when the electro-magnet
is energised, the armature holds the cut-out in position. The shunt current is
only passed through the magnet coil for a very short time, and, to prevent the
armature returning to its normal position too quickly, we provide a damping
device; such, for example, as a dash-pot, in connection with the electro-magnet
armature which prevents it from too quickly moving back to the normal position
and releasing the cut-out when the shunt current is cut off, the dash-pot, or the
like, being so arranged that the time taken by the magnet armature to regain
its normal position is considerably greater than the time during which the large
volume of current passes through the armature coils of the electric motor prior
to the armature revolving and so cutting down the current to its working
volume.
We will describe with reference to the accompanying drawings apparatus
arranged in accordance with our invention.
Figure 1 is a longitudinal sectional elevation, Figure 2 a transverse sectional
elevation, and Figure 3 a plan, part in section, of the electro-magnet arrange-
ment for working the points. a is a box provided with a cover (these being pre-
ferably of cast iron) and containing the electro-magnets 66* which are fixed to a
cast iron framing 62. c are wrought iron hoods to each of which is attached a
pole piece d having a conical recess at the end. e are other wrought iron core
pieces attached to wrought iron breech pieces f, and these core pieces are coned
at the end to fit respectively the coned recesses in the pole pieces d.
g, are brass
bobbins one fixed on each of the core pieces e and carrying a coil of wire for
energizing the magnets, which coils are sufficiently long to enclose the space
between the pieces e and d. The bars connect the wrought iron hoods c of the
two magnets together. These bars may be of brass, but preferably are of
wrought iron, secured by brass screws and distance pieces to prevent magnetic
leakage from magnet to magnet. j is a wrought iron link piece which connects
the magnets to the rod k for working the points.
Figure 4 is a longitudinal sectional elevation Figure 5 a transverse sectional
elevation and Figure 6 a plan of the locking bolt magnet and switches. is a
rod attached to, and working with, the points, and ² is a wrought iron slide piece
which is connected to the said rod and which is secured in position by the
bolt. This bolt is attached to, and actuated by, the electro magnet which
is constructed in the same manner as the magnets for working the points described
with reference to Figures 1, 2 and 3. are spiral springs which bring the
bolt to its normal, and locked, position when the electric current is cut off.
to are switches. m is a frame moving on a centre at n, which frame carries
0 brass contacts which are shewn for one position of the points between the
switches 16 and 17, when the said frame is in the position shewn at o Figure 4
closing the said switches 1*15 16 and 7. In the other position of the points the
said frame is in the position shewn by the dotted line at p Figure 4 and closes
the switches 18 19 110 and Z¹¹.
5
Figure 7 shews two forms of the bolt 3 for locking the slide piece ². In one
form the locking bolt is provided with a wedge shaped nose 7 which enables
the bolt to be partially forced out should the points be run through. In the other

page_text: form of the locking bolt, the nose is formed as shewn at q¹ to give a locking which
would not be forced out should the points he run, through.
Figure 8 is a diagram illustrating the apparatus arranged for working a pair
of points. A, B, C, are respectively the lever in the signal cabin, the electric
switch, and the electric check lock which are described in the Specification of the
aforesaid Letters Patent No. 12128 97. I is the electro-magnetic arrangement
as herein before described with reference to Figures 1, 2 and 3, and E is the bolt
locking and switching device herein before described with reference to Figures 4,5
and 6. Lever 4 being pulled over the current leaves the battery, or source of
power at a², passes through the magnet coil to the switch c², contact piece d
and switch to f2 and through the main switch to and back to the battery
at . The magnet coil b is now. energized, and the bolt is withdrawn and
contact made at switches and the contact at the switch m² being broken.
The current has now two paths, one to energize the magnet and the other
from through the switches and 2 and the magnet coil b to f and through
the main switch F1 to 2 and thence back to the battery at h². The magnet coil b
is now energized, the points reversed and contact broken at the switches c d e²,
the magnet coil b₁ is no longer energized and the bolt 3 shoots into its normal
position, locking the points in their reversed position, and contact is broken at
the switches which cuts off current from the magnet coil b. The check lock
circuit is now complete and current passes from 2 to 2 through the switches m²
and through the check lock coil to the switch r contact piece s to t and
thence to ². The check-lock coil being energized the armature is attracted,
thus freeing the lever L, the stroke of which may now be completed. To work
from the pulled over to the normal position the current passes from a² through
the magnet coil 6' switch and main switch F2 to a and back to 12. The coil b* is
now energized and the points are moved over to their normal position and contact
broken at the switch which cuts off current from the coil b', the bolt 3 shooting
back to its normal position, and locking the points in their normal position and
completing the check-lock circuit through the switches m² and z. The check lock
coil q is now energized and the armature u attracted, and the lever L is freed
and can be put back into its normal position.
Figure 9 illustrates the aforesaid arrangement for protecting a motor armature
from damage due to a rush of current through the armature coils when the arma-
ture is at rest. is a mercury cut-out which may be of any known or suitable
form. is a low resistance coil through which passes the current to the motor
armature, which, if it greatly exceed a safe working current, so energizes the
magnet of the cut-out that the leg is withdrawn from the mercury in the cup d3
and the current to the armature is cut off. On the leg is a pin e³. 3 is a
hooked lever connected by the rod to the lever h³ centered at 3. is an
electro-magnet which when energized attracts the armature 13 attached to the
lever and draws it down together with the lever f³ the hooked end of which
engages with the pin e³ and so holds the cut-out leg in position in the mercury.
m³ is a dash pot, or equivalent device, which allows the rod n³ attached to the
lever to freely move down by the valve o³ being opened. As soon as the cur-
rent is cut off from the electro-magnet the spring 7 draws the lever 3 back
to its normal position, but slowly, as on the upward movement of the rod n³ the
valve o³ is closed, and the piston in the dash pot cylinder can only move up as the
air is gradually admitted."
The working is as follows: If the apparatus lever X be pulled over, the first
movement closes the switch and a current of electricity will pass through the
electro magnet with the result herein before described. As the lever moves
further the switch for passing the current to the motor is closed and the switch g
opened, but the hook-shaped lever f³ is not immediately disengaged from the
pin e on the cut out, the dash-pot plunger occupying sufficient time in returning
to its normal position to allow the motor armature to start running and so cutting
down the current to its working strength. The current to the motor passes from

page_text: the battery, or source of power, to the coil 63 through the casting of the cut-out
to the leg through the mercury to the mercury cup d³ (which is insulated from
the cut out casting) to the motor, and from the motor to a switch (not shewn)
actuated by the lever X back to the battery.
Having now particularly described and ascertained the nature of this inven-
tion, and in what manner the same is to be performed we declare that what we
claim is:-
1. In apparatus for working railway points and signals by electricity the com-
bination of an electro-magnet, or electro magnets, for working the points, and
an electro magnet or electro magnets for actuating the bolt or device for locking
the points and switches for preventing the improper operation of the lever and
signals substantially as herein before described and illustrated by Figures 1 to 8
of the accompanying drawings.
2. In an electro magnetic device for working railway points a plunger worked
by the said device and having a bolt with a wedge shaped locking part to permit
of the automatic unlocking of the points substantially as herein before described
and illustrated at in Figure 7 of the accompanying drawings.
3. In apparatus for working railway points and signals by electricity the com-
bination of an automatic cut-out, an electro magnet, and a dumping device or
dash pot substantially as herein before described and illustrated in Figure 9 of
the accompanying drawings.
D
111011 day of December 1809
JOHNSONS & WILLCOX,
47, Lincoln's Inn Fields, London, W.C., Agents.