Improvements in or connected with Vacuum Railway Brakes.
Year: 1897

page_text: PROVISIONAL SPECIFICATION.
Improvements in or connected with Vacuum Railway Brakes.
I, STEPHEN ALLEY, of the Sentinel Works, Palmadie, in the County of Glasgow,
North Britain, Engineer, do hereby declare the nature of this invention to be as
follows, that is to say:-
-
My said invention has for its object to provide improved accessories for vacuum
railway brakes, such accessories being provided to enable the brakes to be con-
trolled in a more satisfactory manner in certain circumstances.
In carrying out my invention I employ, in connection with each vehicle, a valve
chest to which I connect the usual train pipe and the pipes leading respectively to
the top and bottom of the brake cylinder. The train pipe and the pipe leading to
the top of the brake cylinder communicate with the chamber of the valve chest
through ports controlled by ball valves carried loosely in a cradle-like piece capable
of being rocked on a central fulcrum by means of a spindle which is jointed to it.
The spindle passes through a diaphragm of rubber or other suitable material fixed
to a disk on the spindle and held in an annular recess in the valve chest by a dome-
like cover in a manner to form an airtight joint, and to allow of the spindle having
a reciprocating movement to rock the cradle. The cradle spindle passes through
the valve chest cover and has jointed to it a lever for moving it. Acting between
a boss on the inner side of the valve chest cover and a nut or other enlargement
on the cradle spindle there is a helical spring which encircles the spindle.
In its normal or working position the cradle is placed so that the port leading
to the top of the brake cylinder is closed by its valve, while the port leading to the
train pipe is open this position of the cradle being maintained by the action of the
helical spring encircling the spindle. The air is exhausted from the top and
bottom of the brake cylinder through the train pipe, and when it is desired to
apply the brake, air is as usual let into the train pipe and enters the valve chest,
proceeding thence to the bottom of the brake cylinder, the air being at the same
time prevented from entering the port (which is closed by its valve) leading to the
top of the brake cylinder.
When it is necessary to release the brake by hand, as for example during
shunting operations, the cradle is rocked to lift from its seat the valve closing the
port leading to the top of the brake cylinder, thus allowing air to have access thereto
so as to destroy the vacuum.
In the event of leakage taking place in the brake cylinder or valve chest, the
valve controlling the port leading to the train pipe can be closed by moving the
spindle outwards to rock the cradle, and the cradle can be maintained in that
position by means of a pin attached to the chest, which pin can be inserted into
holes provided to receive it in the cover and the spindle.
Dated this Third day of April 1897
EDMUND HUNT,
Applicant's Agent.

page_text: Improvements in or connected with Vacuum Railway Brakes.
I, STEPHEN ALLEY, of the Sentinel Works; Palmadie, in the County of Glasgow,
North Britain, 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, that is to say:-)
1'
My said invention has for its object to provide improved accessories for vacuum
railway brakes, such accessories being provided to enable the brakes to be controlled
in a more satisfactory manner in certain circumstances.
And in order that my said invention and the manner of performing the same
may be properly understood, I hereunto append a sheet of explanatory drawings"
to be hereinafter referred to in particularly describing my improvements.
Figures 1, and 2, on the accompanying sheet of drawings, are longitudinal
sections as at right angles to each other and Figure 3, is a transverse section of
my improved accessories for vacuum railway brakes. Figures 4, and 5, are
respectively side and end elevations, showing a detail in connection therewith. In
these drawings the same reference letters are used to mark the same or like parts
wherever they are repeated.
In carrying out my invention I employ in connection with each vehicle a valve
chest, A, to which I connect the usual train pipe, B, and the pipes, C, and D,
leading respectively to the top and bottom of the brake cylinder (not shown). The
train pipe, B, and the pipe, C, leading to the top of the brake cylinder communicate
with the chamber, E, of the valve chest, A, through ports, F, and G, controlled by
ball valves, H, and K, carried loosely in a cradle-like piece, I, capable of being
rocked on a central fulcrum, M, by means of a spindle, N, which is jointed to it.
The spindle, N, passes through a diaphragm, P, of rubber or other suitable material
fixed to a disk, Q, on the spindle and held in an annular recess, R, in the valve
chest, A, by a dome like cover, S, in a manner to form an airtight partition, and
to allow of the spindle having a reciprocating movement to rock the cradle, L.
The cradle spindle, N, passes through the cover, S, and has jointed to it a lever, T,
for moving it. Acting between a boss, U, on the inner side of the cover, S, and a
nut, V, or other enlargement on the cradle spindle, N, there is a helical spring W,
which encircles the spindle.
In its normal or working position the cradle, L, is placed so that the port, F,
leading to the top of the brake cylinder is closed by its valve, H, while the port, G.
leading to the train pipe, B. is open, this position of the cradle being maintained'
by the action of the helical spring, W, encircling the spindle, N. The air is
exhausted from the top and bottom of the brake cylinder through the train pipe, B.
and when it is desired to apply the brake, air is as usual let into the train pipe and
enters the valve chest, A, proceeding through the port, G, chamber, E, and pipe, D,
to the bottom of the brake cylinder, the air being at the same time prevented from
entering the port, F, (which is closed by its valve, H,) leading to the top of the
brake cylinder.
When it is necessary to release the brake by hand, as for example during
shunting operations, the cradle, L. is rocked to lift from its seat the valve, H,
closing the port, F, leading to the top of the brake cylinder, thus allowing air to
have access thereto so as to destroy the vacuum.
In the event of leakage taking place in the brake cylinder or valve chest, A,
the valve controlling the port, G, leading to the train pipe, B, can be closed by
moving the spindle, N. outwards to rock the cradle, and the cradle
can be maintained in that position by means of a forked wedge or
key, X, which is inserted between the inner end of the lever, T, and the

page_text: cover, S. Or the cradle, L, may be maintained in the desired position by means
of a pin (not shown) attached to the chest, A, which pin can be inserted into holes
provided to receive it in the cover, S, and the spindle, N.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same is to be performed, I declare that what
I claim is
1
In vacuum railway brakes providing in connection with each vehicle a valve
chest, to which are connected the usual train pipe, and the pipes leading respectively
to the top, and bottom of the brake cylinder, the train pipe and the pipe leading
to the top of the brake cylinder communicating with the chamber of the valve
chest through ports controlled by ball valves carried loosely in a cradle-like piece
capable of being rocked on a central fulcrum by means of a spindle which is jointed
to it, means being provided for maintaining the cradle-like piece in an inward or
outward position to allow the closing or opening of the ports by the ball valves,
substantially as and for the purposes hereinbefore described.
Dated this Twenty-eighth day of December 1897.
EDMUND HUNT,
Applicant's Agent.