IMPROVEMENTS IN MECHANISM OR ARRANGEMENTS FOR INTERLOCKING RAILWAY POINTS AND SIGNALS
Year: 1876

page_text: LETTERS PATENT to Francis William Webb, of Crewe, in the County of
Chester, Mechanical Engineer, for the Invention of "IMPROVEMENTS IN
MECHANISM OR ARRANGEMENTS FOR INTERLOCKING RAILWAY POINTS AND
SIGNALS."
Sealed the 9th September 1876, and dated the 6th June 1876.
PROVISIONAL SPECIFICATION left by the said Francis William Webb at
the Office of the Commissioners of Patents on the 6th June 1876.
FRANCIS WILLIAM WEBB, of Crewe, in the County of Chester, Mechanical
Engineer. "IMPROVEMENTS IN MECHANISM OR ARRANGEMENTS FOR INTERLOCKING
RAILWAY POINTS AND SIGNALS."
Hitherto two systems of locking the levers or handles of railway points and
signals have been in use; one system whereby some part of the movement of the
lever handle causes the mechanism to lock or unlock, or both lock and unlock, other
lever handles, and the other and more recent system whereby the movement of
catch (which enters the notch in the quadrant and retain the lever in position)
locks or unlocks before any movement whatever takes place in the lever handles,
which latter movement has no action whatever to operate upon the locking
mechanism.
My improvements relate to mechanism upon the former and older principle of
action, and consists in an improved combination and arrangement of mechanism
for the purpose, namely, the lever handle is held in its place when pulled over in
either extreme position by a weight, catch, or a bolt which enters notches in the
quadrant such as is commonly used for retaining a lever in position. The locking
mechanism consists of notched bars and cross bars having studs as usual. The
notched bar of each lever handle has a movement given to it by the first part of
the movement of the lever handle, and it has a further movement in the same
direction by the latter part of the movement of the lever handle; such movements
will operate to effect the locking, unlocking, and back locking required. Move-
ment is imparted to the notched bar by an adjustable connecting rod jointed to the
end of the notched bar, and to one end of a weigh-beam lever having its fulcrum
on the lever handle. This beam lever has a short right angle projecting arm which
just before the lever handle arrives at either of its extreme positions will come
against one of two stops upon the side of the quadrant frame, and so give move-
[Price 6d]

page_text: ment to the beam lever one way or the other. The two ends of the beam lever
have also projections, which when the lever handle is being moved from one position
to the other will rest or ride upon a segmental ledge or surface on the side of the
quadrant frame, and thus the notch bar is prevented from moving while the lever
is passing from one extreme to the other, except just before it arrives at either end,
at which point the segmental ledge ends and allows the short right angle pro-
jecting arm before mentioned to move the beam lever. The projections at the ends
of the beam lever may be bevelled so as to easily ascend upon the segmental ledge
on the quadrant the moment the lever handle begins to be moved. In pulling
the lever handle over that end of the beam lever to which the connecting rod is
attached rises, and while passing over it remains in that position, and on arriving
at near the other extreme the right angle projecting arm strikes against the stop
and causes the same end of the beam lever to be further lifted. When the lever
handle is pushed back the movements of the beam lever are reversed.
SPECIFICATION in pursuance of the conditions of the Letters Patent filed by
the said Francis William Webb in the Great Seal Patent Office on the 28th
November 1876.
FRANCIS WILLIAM WEBB, of Crewe, in the County of Chester, Mechanical
Engineer. "IMPROVEMENTS IN MECHANISM OR ARRANGEMENTS FOR INTERLOCKING
RAILWAY POINTS AND SIGNALS."
Hitherto two systems of locking the levers or handles of railway points and
signals have been in use; one system whereby some part of the movement of the
lever handle causes the mechanism to lock or unlock, or both lock and unlock,
other lever handles, and the other and more recent system whereby the movement
of the catch (which enters the notch in the quadrant and retains the levor in
position) locks or unlocks before any movement whatever has taken place in the lever
handles, the movement of which has no action whatever to operate upon the
locking mechanisın.
My improvements relate to mechanism upon the former and older principle of
action, and consists in an improved combination and arrangement of meclianism for
the purpose, namely, the lever handle is held in its place when pulled over in either
extreme position by a weight, catch, or a bolt which enters notches in the quadrant,
such as is commonly used for retaining a lever in position. The locking mechanism
consists of notched bars and cross bars having studs as usual, or of such an arrange-
ment of bars as will be herein-after described. The notched bar or other bar or bars
of each lever handle has a movement given to it by the first part of the movement
of the lever handle, and it has a further movement in the same direction by the
latter part of the movement of the lever handle; such movements will operate to
effect the locking, unlocking, and back locking required. Movement is imparted
according to one modification to the notched bar by an adjustable connecting rod
jointed to the end of the notched bar and to one end of a weigh beam or double
bell-crank lever having its fulcrum on the lever handle. This beam lever has a
short right angle projecting arm which, just before the lever handle arrives at
either of its extreme positions, will come against one of two stops upon the side of
the quadrant frame, and so give movement to the beam lever one way or the other.
Each end of the beam is provided with a projection or hook, and upon the lever
handle being moved from either of its extreme positions the projection or hook at
one end will at once rise or unhook, and the projections will then ride upon the
seginental ledge or surface on the side of the quadrant frame, the notched bar being
thus prevented from moving while the lever is passing from one extreme to
the other, except just before it arrives at either end, at which point the short right
angled projecting arm before montioned strikes against the stop and causes the end
already lifted to be further lifted and the other end to be depressed and hooked

page_text: over the end of the segmental ledge. The motion of one end of the beam lever
thus described is imparted to the locking bars by the adjustable connecting rod.
Should one of the vertical notched bars be locked the weigh-beam lever is retained
in its hooked position, thus preventing the hand lever to which it is attached
from being moved. The peculiar construction of the weigh-beam lever ensures
that when a locked lever handle is pulled at the greater part of the strain is
taken directly by the frame, a very small part only being transmitted to the
locking bar.
My improved combination and arrangement of mechanism is illustrated by
Fig. 1 of the Drawings, a sectional end elevation; but other combinations and
arrangements of mechanism for accomplishing the same object, being modifications
of the combination shown by Fig. 1, will be herein-after described by reference to
the other Figures of the Drawings.
A is part of the wood framing to which the mechanism of a set of levers is sup-
posed to be secured; a, frames carrying the locking mechanism; b, one of the
notched bars which can slide freely up and down in the framing, its upper or hook
end embracing the head of the fulcrum bolt or stud for the lever handle; c, arc
horizontal locking bars carrying the studs c
When these studs come in the
notches of the bars (b) the lever to which the bar is connected is locked, and when-
ever the parts of the bar (6) between the notches are in the way of a stud in one of
the horizontal bars it locks the lever handle which actuates that bar when at liberty,
this action being the same as that of ordinary locking mechanism. & is the quadrant
framing; e, the lever handle secured in a cast-iron fulcrum part; c', the fulcrum stud
for the lever handle; e² is a catch weight which can slide up and down the lever
handle and can catch upon the step at each end of the upper surface of the quadrant.
The catch weight is actuated by a handle having its fulcrum at the upper end
of the lever handle (e), the connection being formed by a rod (e) jointed to the
weight catch and handle. Upon the lever handle (c) a weigh-beam lever (c) is
mounted on a fulcrum at (e), and this lever has a projection or hook at each end
from its under side which hooks upon the ends of a ledge cast upon the side of the
quadrant d. There is also upon the under side and at the middle of the lever
another projection c7 which will come against the inside of the end projections from
the ledge in either extreme of the lever handle; these projections ² extending
on one side beyond the edge of the ledge d. One end of the beam lever is
connected by an adjustable rod f with the vertical notched bar b. When the lever
handle (e) is to be moved the weight catch of is lifted, then the first part of the
movement of the lever handle will cause the lowest end of the beam lever (as shown
in Fig. 1) to lift, so that the under side of the projections at the ends of the beam
lever will ride upon the upper side of the ledge (d), this will lift the notched bar (b),
and when the lever handle gets to near the other extreme the central projection e
upon the bean lever will come against the inside of the projection (d) at that end
of the ledge, and will cause the notched bar b to be lifted another step higher, these
movements of the beam lever being reversed when the lever handle is pushed back.
Fig. 2 is a side elevation, and Fig. 2 is a plan to illustrate a modification in
which the lever handle and weigh-beam lever are arranged and act in the same
manner as that shown by Fig. 1. But the locking mechanism acts upon a different
principle. are levers mounted upon fulcrum studs g¹ in the framing, and g² and
gare plain channeled bars without notches jointed to the ends of the levers y.
are cross locking bars which may be at one or on each side of the parallel bars g²
and . These cross bars have studs projecting towards the parallel bars, so that
when any one of these studs comes opposite the edge or edges of the parallel bars
they cannot be moved from the position in which they are shown in Fig. 2. Con-
sequently the lever handle will be locked as one of the bars is connected by an
adjustable rod with the weigh-beam lever e, and when that lifts the parallel bars
will move asunder and approach the cross bars, this movement being permitted
when there are no studs in the cross bars that come opposite to the edge of the
parallel bars g and g³. When the parallel bars are asunder they will prevent

page_text: such of those cross bars as are intended to be locked from being moved, as the
studs will be obstructed by coming against the sides of the parallel bars. The
cross locking bars are by preference actuated by bell-crank levers m with their
fulcrums on vertical studs in brackets secured to the framing o, as shown in Fig. 2.
The end of one arm of the bell crank (m) takes into the channel in one of the
parallel bars (g or g³) and the end of the other an into a part attached to the
cross bar (see Fig. 20).
For illustration, four sets of parallel ruler locking bars are shown in Fig. 2ª, those
bars for the lever handles numbered 1 and 3 being in the position they assume
when the lever handles are pulled over, in which position No. 3 lever handle will
be back locked by No. 1 lever handle. No. 1 lever handle also at the same time
locking No. 2. When No. 2 lever handle is pulled over it unlocks No. 4, and
when the latter lever handle is pulled over it back locks No. 2 lever handle.
Fig. 3 is a sectional end elevation shewing a combination of mechanism with
parallel bars g² and g³, similar to those shown by Fig. 2, but the locking mechanism
is brought above the platform for the lever handles, the plane in which the cross
bars are placed being horizontal. A, part of the wood frame for carrying the
iron quadrant frames; & for the lever handles; e, fulcrum of lever handle. A¹,
platform or floor; d, framing for locking mechanism; e, weight catch jointed to
the lever handle and to be actuated by the foot. c, cross bars for locking
mechanism. Each lever handle has a pair of parallel bars and g³ jointed
to the levers having their fulcrums g¹ on studs in the framing. In suitable
grooves and slots in the framing the boss or fulcrum part of a weigh bean lever
es, somewhat similar to that described in reference to Fig. 1, is arranged to slide
to and fro horizontally, movement being imparted to the beam lever by a rod e
jointed to one of its ends and to the lever handle c. The beam lever e³ has a
projection or hook at the under side of its two ends which rides upon the surface
of a ledge formed on the framing when passing from one side to the other, which
projections or hooks keep the beam lever level when moving across, except just
before it arrives at cither end where the termination of the slot in the framing
stops the boss or fulcrum part of the beam lever from travelling further, the last
portion of the stroke of the lever handle serving to tilt the beam lever and hook one
of its projections into a step formed at the end of the ledge. The connecting rod e³ is
jointed to that end of the beam lever furthest from the lever handle e, and the first part
of the movement of the latter, together with the action of the step, causes that end
of the beam lever to rise until its other end rests upon the surface upon which its boss
part slides, this brings the beam lever to its mid or level position in which it passes
across until its other end drops down and hooks over the step at the other end
of the ledge, and this causes that end of the beam lever first lifted to be lifted still
higher. The movements of the beam lever are reversed upon the lever handle
being pushed back. The end of the stud in the beam lever to which the rod e³ is
jointed extends so as to slide freely in a slot passing in the lengthway of one
of the parallel bars, and thus the movements of the beam lever are imparted to
the parallel bars, which are locked when one or more studs upon some one or
more of the cross bars are brought by the action of some other lever handle
opposite the edge or edges of the parallel bars.
Fig. 4 shows a similar arrangement to that illustrated by Fig. 3, with the following
exceptions, viz., there is no sliding beam lever, the beam levere is on a fulcrumi
stud secured in the framing, and forms one of the levers to which the parallel bars
are jointed. The beam lever is similar to the weigh-beam lever eo, shown in Fig. 1,
and is acted upon by the ledge and its projections d, but the beam lever having
its fulcrum immoveable the ledge is moved as it is formed upon a rod jointed to
the lever handle such rod sliding in suitable guides or grooves in the framing.
Fig. 5 is a similar view to Fig. 4, and represents a similar combination with the
following exceptions:-The part which forms the ledge and its projections (² is
formed in one piece with the lever handle e, and is curved to a radius struck from
the fulcrum of the lever handle, there is only one set of cross bars c and one parallel

page_text: bar g, and this is curved, and the cross bars are arranged to radii struck from the
same centre.
I have now particularly described the nature of the said Invention and the mode
of carrying the same into effect, and claim as my Invention-
Firstly. The weigh-beam lever with its projections acting in the manner and for
the purpose herein-before described and illustrated by the Drawings.
Secondly. The combination and arrangement of mechanism hercin-before described
and illustrated by Fig. 1 of the Drawings.
Thirdly. The combination and arrangement of mechanism herein-before described
and illustrated by Figs. 2 and 2ª, and the modifications thereof illustrated by Figs. 3,
4, and 5 of the Drawings.
In witness whereof, I, the said Francis William Webb, have hereunto set my
hand and seal, this Twenty-seventh day of November, in the year of our
Lord One thousand eight hundred and seventy-six.