IMPROVEMENTS IN RAILWAY BUFFER STOPS
Year: 1880

page_text: LETTERS PATENT to Alfred Andrew Langley, of 10, Kent Terrace, Clarence
Gate, Regent's Park, in the County of Middlesex, Chief Engineer Great
Eastern Railway, for an Invention of "IMPROVEMENTS IN RAILWAY BUFFER
STOPS."
PROVISIONAL SPECIFICATION left by the said Alfred Andrew Langley
at the Office of the Commissioners of Patents on the 30th October 1880.
ALFRED ANDREW LANGLEY, of 10, Kent Terrace, Clarence Gate, Regent's Park,
in the County of Middlesex, Chief Engineer Great Eastern Railway. "IMPROVE
MENTS IN RAILWAY BUFFER STOPS."
This Invention has for its object improvements in railway buffer stops.
In order to prevent railway carriages and trains overrunning the end of a siding
or line of railway, I provide hydraulic buffer stops, by means of which I am able to
bring them to rest with less shock and risk of breakage than results from the use
of buffer stops of other and ordinary constructions.
My hydraulic buffer stop consists of a pair of cylinders, mounted horizontally, and
aligned with the buffers of the carriages on the railway. A piston rod passes
through each cylinder and through stuffing boxes at the cylinder ends.
The piston rods are fixed to a cross head, consisting of a baulk of timber adapted
to receive directly the impact of the carriage buffers. This baulk or cross head is
also supported from a pair of wheels standing upon the line of railway. The pistons
within the hydraulic cylinders do not fit tightly, but nevertheless, they offer con-
siderable resistance to the rapid transference of water from one end of the
cylinder to the other. The two cylinders are connected in rear of the pistons by a
cross pipe to ensure equality of resistance, and a connection is made between this
cross pipe and an air vessel, or closed cistern partly filled with water, but in which
also some air is confined. A weight suspended in a pit by a chain is employed to
draw the pistons forward in the cylinders, and keep the apparatus in position ready
to meet the impacts or shocks which it is intended to receive. When impact takes
place the pistons are driven back, and as they recede they offer a resistance which
gradually brings the carriage or carriages to rest, and this buffer stop causes no
rebound.

page_text: The arrangement may be varied by the substitution of a single cylinder, with
guides on either side for the pair of cylinders described above.
According to another modification tightly fitting pistons are employed, and then
all the water displaced by the piston when it is driven in is forced up into the air
vessel or cistern. There is a cock or valve upon the pipe forming the connection
with this air vessel or cistern, and an air cock or valve is also provided at the top
of the air vessel. By the proper adjustment of these cocks or valves the apparatus
is regulated to offer the amount of resistance desired. In this arrangement it is not
necessary to employ a weight or weights to cause the return of the pistons to the
fore ends of the cylinders after they have been driven in by the impact upon the
buffer stop of a carriage or train.
In lieu of water a liquid which is not liable to be frozen may sometimes be
substituted with advantage.

page_text: SPECIFICATION in pursuance of the conditions of the Letters Patent filed
by the said Alfred Andrew Langley in the Great Seal Patent Office on
the 29th April 1881.
ALFRED ANDREW LANGLEY, of 10, Kent Terrace, Clarence Gate, Regent's
Park, in the County of Middlesex, Chief Engineer Great Eastern Railway.
"IMPROVEMENTS IN RAILWAY BUFFER STOPS."
This Invention has for its object improvements in railway buffer stops.
In order to prevent railway carriages and trains overrunning the end of a siding
or line of railway, I provide hydraulic buffer stops, by means of which I am able to
bring them to rest with less shock and risk of breakage than results from the use
of buffer stops of other and ordinary constructions.
My hydraulic buffer stop consists of a pair of cylinders, mounted horizontally,
and aligned with the buffers of the carriages on the railway,
A piston rod passes through each cylinder and through stuffing boxes at the
cylinder ends.
The pistons within the hydraulic cylinders do not fit tightly, but nevertheless, they
offer considerable resistance to the rapid transference of water from one end of the
cylinder to the other.
A weight suspended in a pit by a chain is employed to draw the pistons forward
in the cylinders and keep the apparatus in position ready to meet the impacts or
shocks which it is intended to receive. When impact takes place the pistons are
driven back, and as they recede they offer a resistance which gradually brings the
carriage or carriages to rest, and this buffer stop causes no rebound.
The arrangement may be varied by the substitution of a single cylinder, with
guides on either side for the pair of cylinders described above.
According to another modification tightly fitting pistons are employed, and then
all the water displaced by the piston when it is driven in is forced up into a cistern.
There is a valve upon the pipe forming the connection with this cistern. By the
proper adjustment of this valve the apparatus is regulated to offer the amount of
resistance desired. In this arrangement it is not necessary to employ a weight or
weights to cause the return of the pistons to the foro ends of the cylinders after they
have been driven in by the impact upon the buffer stop of a carriage or train. In
lieu of water a liquid which is not liable to be frozen may sometimes be substituted
with advantage.
In order that my Invention may be most fully understood and readily carried
into effect I will proceed to describe the Drawings hereunto annexed.
DESCRIPTION OF THE DRAWINGS.
Figures 1 to 7 on Sheet 1 of the Drawings represent one form of my improved
buffer stop.
Figure 1 is a longitudinal and vertical section, Figure 2 is a front clevation,
Figure 3 is a plan, partly in section, of the apparatus complete; Figure 4 is a
longitudinal section of one of the cylinders shown separately to a larger scale;
Figures 5, 6, and 7 are transverse sections of the cylinder taken on the lines 1, 1,
Figure 4, 2, 2, Figure 4, and 3, 3, Figure 4, respectively. a, a, are piston rods,
having upon them pistons a¹, a¹; the pistons are contained within cylinders b, b,
and the piston rods pass through stuffing boxes in the cylinder ends; a², a³, are
buffer heads upon the piston rods to receive the impact of a train or carriage running
against the buffer stop. In place of separate buffer heads the piston rods may be
connected by a cross baulk or beam passing from the one to the other. They may

page_text: also, if desired, be supported and guided by guide wheels running on the rails, but
I now prefer to employ stationary guides at c, c, as shown. d, d, are weights
attached to the hinder ends of the piston rods by chains which are led around the
guide pulleys e, e. When the pistons are driven back the weights are raised, and
after the shock the weights bring the pistons gradually back to the position in
which they should stand ready for action. The cylinders b, b, are charged with
water or liquid, and there is room all round the pistons a', a', for the liquid to pass
them. Now, the resistance offered by the liquid to the movement of the pistons
will depend on two things, viz., the velocity of the movement and the amount of
space between the piston and the cylinder. Now, the velocity of movement will
always be greatest at the commencement of the stroke, and should be reduced to
nothing by the time that the stroke is complete; nevertheless, the resistance offered
should remain as nearly constant as may be; it should not be excessive at the
commencement of the stroke, and when the stroke has been nearly completed the
resistance should remain sufficient for the buffer stop to be thoroughly effective. 1
These conditions the use of the loose piston enables me to satisfy in a very simple
manner I do not bore the cylinder parallel, but taper in the proportions which
the Drawings indicate, so that as the piston is forced back the space by which the
liquid has to pass between it and the cylinder diminishes, and a compensation is so
made for the smaller speed of the piston. f.f, are pipes provided with stop cocks,
and passing to a cistern from which liquid is supplied to keep the cylinders full.
9, 9, are pipes, also with cocks upon them, which are only opened when it is
desired to empty the cylinders. The cylinders b, b, may, if desired, be connected
by a cross pipe, which will ensure an equality of pressure between them.
The Figures 8 to 12 on Sheet 2 of the Drawings represent another form of my
improved buffer stop.
Figure 8 is a longitudinal and vertical section; Figure 9 is a transverse and
vertical section; Figure 10 is a plan; Figure 11 is a longitudinal section of one of
the cylinders, shown separately to a larger scale; Figure 12 is a transverse section
of one of the cylinders. In this arrangement the cylinder is not bored taper, but in 3
lieu thereof taper filling pieces b', 6', are fixed within it. The piston is notched out
on either side to admit these filling pieces, but otherwise it is made a loose fit in the
cylinder. The notches in the piston permit the liquid to pass it as the piston is
forced back. At the commencement of the stroke these notches are open wide, so
that the piston may not experience an excessive resistance, even when put into 3
comparatively rapid movement, but as the piston is forced back the pieces b¹
occupy more and more of the notches and reduce the size of the passages, so that,
notwithstanding the diminishing speed of the piston, a proper amount of resistance
is maintained.
Another feature in which this arrangement differs from that shown by Sheet 14
of the Drawings is that the piston rods are not carried through the cylinders, but
terminate at the pistons, and the weights d, d, are dispensed with. The piston
rods, which are of large diameter, when driven back displace some of the liquid
from the cylinders and drive it up a pipe into an elevated cistern. Afterwards
the liquid returns by gravity into the cylinders and drives the pistons to the foro 4
ends of the cylinders, where they should stand ready to receive the impact of the
vehicles.
i, i, are safety valves which will open to relieve the cylinders before they can
be exposed to a strain sufficient to burst them or to injure the mechanism.
The Figures 13 to 18 on Sheet 3 of the Drawings represent another form of my 5
improved buffer stop, in which I employ pistons fitting the cylinders fluid tight,
and when driven back the piston displaces the liquid from the cylinders and drives
it past a valve into a cistern. In this arrangement also the pistons are caused to
return to the fore ends of the cylinders by the hydraulic pressure.
Figure 13 is a longitudinal and vertical section; Figure 14 is a transverse and 5
vertical section; Figure 15 is a plan; Figure 16 is a longitudinal section of one of
the cylinders to a larger scale; Figures 17 and 18 are end views of the cylinder.

page_text: The cylinders bare bored parallel and the pistons a¹ are provided with cupped
leathers to prevent leakage past them. k, k, are pipes by which, when the pistons
are driven back, the liquid is able to escape from the cylinders; 1, 1, are valves at
the upper ends of the pipes k, k; they are kept to their seats by the weights m, m,
and springs n, n, which however yield to allow the liquid to pass whilst main-
taining in the cylinders a sufliciently high pressure to render the buffer stop fully
effective; o, o, are the cisterns which receive the liquid expelled from the
cylinders. The liquid is able to return to the cylinders after the blow by the small
perforations, ¹, formed in the pipes below the valves . As the liquid
descends the pistons gradually return to the fore end of the cylinders. If desired,
valves opening inwards may be supplied to the apertures kl.
Having thus described the nature of my said Invention and the manner of
performing the same, I would have it understood that I claim,—
First. My improvements in hydraulic buffer stops, substantially as described in
respect to the Figures on Sheets 1 and 2 of the Drawings annexed, and especially
that feature thereof which consists in causing the blow and pressure of the carriages
against the buffer stop to be conveyed to pistons contained within cylinders
charged with water or liquid, which pistons do not tightly fit the cylinders, but
when driven inwards permit liquid to pass between their peripheries and the sides
of the cylinders.
Second. My improvements in hydraulic buffer stops, substantially as described
in respect to the Figures on Sheet 1 of the Drawings annexed, and especially that
feature thereof which consists in bringing back the pistons after the impact of the
carriages upon the buffer stop by means of a descending weight.
Third. My improvements in hydraulic buffer stops, substantially as described in
respect to the Figures on Sheet 3 of the Drawings annexed, and especially that
feature thereof which consists in causing the blow and pressure of the carriages
against the buffer stop to be conveyed to pistons contained within cylinders charged
with water or liquid, which pistons fit the cylinders, and when in action drivo
liquid out of the cylinders past regulated valves.
Fourth. My improvements in hydraulic buffer stops, substantially as described
in respect to the Figures on Sheets 2 and 3 of the Drawings annexed, and especially
that feature thereof which consists in causing the pistons to return, after action
by the supply of liquid from an elevated cistern, to replace liquid expelled at
the time of impact.
Fifth. My improvements in railway buffer stops, substantially as described and
illustrated by the Drawings annexed.
In witness whereof, I, the said Alfred Andrew Langley, have hereunto set
my hand and seal, this Eighteenth day of March, in the year of our Lord
One thousand eight hundred and eighty one.
ALFRED LANGLEY. (LS.)