IMPROVE- MENTS IN APPARATUS FOR WORKING AND GOVERNING THE ACTION OF RAILWAY POINTS AND SIGNALS, A PART OF WHICH IS APPLICABLE FOR OTHER PURPOSES
Year: 1867

page_text: PROVISIONAL SPECIFICATION left by Thomas Frederick Cashin at the
Office of the Commissioners of Patents, with his Petition, on the 6th
November 1867.
I, THOMAS FREDERICK CASHIN, of Sheffield, in the County of York, Civil
Engineer, do hereby declare the nature of the said Invention for "IMPROVE-
MENTS IN APPARATUS FOR WORKING AND GOVERNING THE ACTION OF RAILWAY POINTS
AND SIGNALS, A PART OF WHICH IS APPLICABLE FOR OTHER PURPOSES," to be as
follows:-
The Invention consists, firstly, of a simple and also a compound lever for
working a single pair of points; secondly, of a compound lever with appliances
for moving and locking the points and signals for junctions; thirdly, of an
apparatus for governing the "set" or position of trailing points in connection
with what is at present understood by the "locking system," so as to admit
of trains running behind the points uncontrolled by the junction levers; and;
fourthly, of an arrangement for closing facing points and preventing the points
from being moved until the whole train shall have passed clear of them. In
substitution of the "switch box "for working a pair of points I use a small metal"
standard with base plate, which I affix to a piece of timber or stone.
metal standard I attach a vertical lever which may be bent to adapt it to any
particular situation, with the fulcrum a sufficient distance above the base platė*
to admit of imparting the necessary "throw" to the rod, and connecting it
To the

page_text: with the points to close them. On an arm projecting from the lever a weight
is fixed which holds the points set in their normal position, but leaves them
free for a train to run through behind them. For places where it is desirable
to lock facing points I use a compound or double lever attached to a standard
and bed plate. The lower lever with a balance weight to hold the points in
their normal position is similar to that just described, except that above the
fulcrum but below the fulcrum of the upper or motive lever it is formed with
a shoulder or fork. The top lever is balanced on its fulcrum at the top of the
standard against a projection or stop, and a pin projecting from it works where
the lever is pressed down into the fork of the lower lever in such manner that
when imaginary lines drawn from the centre of the fulcra to the centre of the
pin or point of pressure approach the formation of a right angle the points
become locked for a train facing them.
Another arrangement by which the points can be locked both ways consists
in forming the top of the lower lever with a slit or slot in which the pin of the
upper lever works when the combination is so regulated that the pin sits at
the bottom of the slot, when turned on either side of the standard at a point
whence the pressure arising from a strain on the lower lever is transmitted
below or direct to the fulcrum of the top lever a dead lock is secured. Two
or more of these levers can be made to interlock by having projections on the
lower levers properly adjusted, and all the levers described can be attached to
'signals to indicate when the points are open and when closed...
For railway junctions where the levers for working points and signals are
grouped together I propose to use frames in which any required number of
compound levers may be introduced, the fulcra for both the upper and lower
levers are formed by horizontal rods attached to the frames. To the bottom of
the lower levers the usual attachments to the points and signals are made; these
levers are thus
shaped at the top, so that the upper levers (indicated by
the dotted lines) which are formed with two horizontal arms and have their
fulcra in or near the centre can when moved on either side cause them to
move towards the side on which the moving arm is depressed. These lower
levers can be made to lock and interlock so that one can hold or be held by
as many of the others as may be desired. For this purpose a horizontal rod
which turns in its bearings in the frame is placed parallel with the fulcra of
the levers, on this rod an arm is fixed with a horizontal attachment jointed to
a projection from one of the levers; all the levers controlled or required to be
locked by this lever must also have jointed attachments to arms projecting
from the side of the rod opposite to that on which the arm actuated by the

page_text: moving lever projects; these attachments must have elongated slots to admit
of all the levers being relieved or "set" before the lever with which they are
interlocked can be moved. This arrangement can be applied to the present
locking system, but I prefer using it in combination with an apparatus which
admits of "trailing" so as to render it only necessary to "set" the points
when trains run in front of them. This apparatus consists of a standard and
simple lever with balance weight similar to that already described as a
substitute for the "switch box," except that the moving arm of the lever is
horizontal, and to this a link or elastic cord is fixed attached to a wire or other
rope similar to those at present in use for signals. These cords working on
pulleys need only be pulled from the box for facing points, they can be weighted
to resume their normal position on being set free and for "trailing" the
connecting link or flexible cord will admit of the points being opened by a
train running through them, and when clear again closed by the action of the
balance weight alone.
For closing facing points or trailing points, when deemed desirable, I propose
to use a strong horizontal bar with an inclined plane at each end, and of such
length as to carry two wheels beyond the points; this bar I fix on crank
bearings which may be weighted to keep the bar normally above the rails, or
the bar may be borne up by a strong spring or springs. At the end next the
tongue of the points the bar is formed with a strong bolt, which when the bar
is depressed by the weight of a train running over it shoots into a groove in a
bolt projecting from the point, and draws it close home when the train is clear
of the points; the springs, or weights, or both, raise the bar and set the points
free.