Improvements in Stop Valves.
Year: 1893

page_text: Date of Application, 7th Mar., 1893
Complete Specification Left, 1st Dec., 1893-Accepted, 20th Jan., 1894
PROVISIONAL SPECIFICATION.
Improvements in Stop Valves.
We, JOHN ADDY HOPKINSON and JOSEPH HOPKINSON, both of the Firm of.
J. Hopkinson & Co., Huddersfield, in the County of York, Engineers, do hereby
declare the nature of this invention to be as follows:-
This invention relates to parallel slide stop valves, and has for its object to
prevent the accumulation of water in the valve chamber, that is to say, in the
space between the valve plates or discs, when the valve is closed.
Such valves are frequently used under circumstances wherein the flow of the
fluid through the valve is not always in the same direction, or in other words
wherein the induction side of the valve may become the eduction and vice versa.
In such circumstances, and with valves- of the kind referred to constructed as
heretofore there is a possibility of condensation water accumulating in the valve
chamber until said chamber is completely filled, and when such excessive accumu-
lation occurs and the water is subsequently heated there is danger of the valve
being injured by the expansion of the confined water.
According to our present invention we obviate the danger of such injury to the
valve by providing means whereby the valve chamber is continuously drained, and
the accumulation and confinement of water therein are effectually prevented.
Our invention is intended to be applied more particularly to valves which have
a bye-pass for equilibrating the pressure on the two sides of the valve prior to
opening said valve and also have a plug as and for the purpose described in the
Specification of former Letters Patent granted to us No. 14098 A.D. 1891.
According to our present invention we provide thoroughfares which form com-
munications between the valve chamber and the induction and eduction sides of
the valve. The thoroughfare leading to the induction or pressure side of the valve
remains open under all circumstances, but we provide for closing the thorough-
fare leading to the eduction side of the valve or the side of least pressure by an
automatically acting ball or other valve so that there is no open thoroughfare
between the induction and eduction sides of the valve until the bye-pass plug is
actually raised from its seat.
In carrying our invention into practice, according to a preferred construction, we
form a thoroughfare longitudinally through the centre of the bye-pass plug, which
thoroughfare leads from the valve chamber to a recess formed in the seat of the
bye-pass plug. From said recess two other thoroughfares lead into the bye-pass,
one on the induction and the other on the eduction side of the valve. In the said
recess we place a supplemental ball or other valve, and retain the same in place by
a nut which is screwed on the lower end of the plug seat. The object of the said
supplemental valve is to close the eduction thoroughfare, which it always docs by
reason of the pressure of the fluid in the induction thoroughfare, which pressure
forces the supplemental valve to the seat of the eduction thoroughfare, thus closing
said thoroughfare, while leaving the induction thoroughfare open to the valve
chamber. Any water which enters the valve chamber is thus free to drain out by
way of the aforesaid induction thoroughfare and bye-pass, and flow back into the
It is thus obvious that
steam pipe on the induction or pressure side of the valve.
the condensed water cannot accumulate or become locked in the valve chamber
This valve is
as is possible in the constructions of valves heretofore in use.
reversible, that is to say, either side can be used as the induction side.
In some cases we arrange the automatic valve in the plug itself, or in the stem
of the plug, it being placed in a recess in a passage through said plug or stem.

page_text: Preferably the hole through the plug forming the communication between the
valve chamber and the bye-pass is so made that the supplemental valve cannot
close the same.
In some instances we apply our invention to valves that have no plug, but have
a bye-pass. In such cases we provide a hole in the bottom of the valve casing
leading into the recess in which the supplemental valve is placed.
In a modification of our invention we dispense with the automatic valve above
referred to, and we substitute therefor a three-way cock or its equivalent which
according to the position in which it is set will make communication simul-
taneously with the valve chamber and the induction and eduction sides of the
bye-pass, or with the valve chamber and either the induction or the eduction side
of the bye-pass. When it is desired to open the valve the attendant first turns
the three-way cock to make communication with the induction and eduction sides of
the bye-pass and the valve chamber so as to place the valve in equilibrium of pressure
whereupon he can open the valve with comparative ease. After closing the valve
it is necessary to turn the three-way cock so as to completely shut off the eduction
thoroughfare while however preserving a communication between the valve chamber
and the induction side of the bye-pass to allow the said chamber to drain.
It is obvious that where our valves are used in water pipes the supplemental
valve above described will obviate the danger of accident arising from the freezing
of the water in the valve chamber.
Dated this 7th day of March 1802
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicants.
COMPLETE SPECIFICATION.
Improvements in Stop Valves.
We, JOHN ADDY HOPKINSON and JOSEPH HOPKINSON, both of the Firm of
J. Hopkinson & Co., Huddersfield, in the County of York, Engineers, 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 :-
This invention relates to parallel slide stop valves, and has for its object to
prevent excessive accumulation of water in the valve-chamber, that is to say, in the
space between the valve plates or discs, when the valve is closed.
Such valves are frequently used under circumstances wherein the flow of the
steam through the valve is not always in the same direction, or in other words
wherein the induction side of the valve may become the eduction side and vice versa.
In such circumstances, and with valves of the kind above referred to constructed as
heretofore there is a possibility of condensation water accumulating in the valve-
chamber until said chamber is completely filled, and when such excessive accumu-
lation occurs and the water is subsequently heated there is danger of the valve
being injured by the expansion of the confined water.
According to our present invention we obviate the danger of such injury to the
valve by providing means whereby when the valve is shut, the valve-chamber is
automatically, or otherwise, placed in communication with the inlet side of the
valve casing whichever side is used as the inlet. The valve-chamber is thus
drained, and the accumulation and confinement of water therein effectually
prevented.
Our invention is intended to be applied to valves which have a bye-pass, and it
is particularly applicable to such valves as are described in the Specification of
former Letters Patent granted to us 14098 A.D. 1891.
In the accompanying drawings,
Figure 1 is a side elevation partly in section of a portion of a parallel slide stop

page_text: valve to which our invention is applied, said valve being of the type having a ping
and bye-pass such as above referred to.
Figure 2 is a section on the line a Figure 1.
Figure 3 illustrates in section a modification of our invention applied to a valve
having no plug attached to the valve spindle.
Figure 4 is a side elevation of another valve showing a modified non-automatic
form of our invention.
Figure 5 is a central horizontal section of Figure 4.
Figures 6 and 7 are details showing the tap hereinafter described in two different
positions.
Like letters denote corresponding parts in all the figures.
A is the valve casing; B, B are the valve plates; C is the valve chamber. We
provide thoroughfares, a, a' a² which form communications between the valve-
chamber C and the induction and eduction sides of the valve. The thoroughfare
leading from the chamber C to the induction or pressure side of the valve remains
open under all circumstances, but in the constructions illustrated in Figures 1 to 3
which will be first described we provide for closing the thoroughfare leading from
the chamber C to the eduction side of the valve or the side of least pressure by an
automatically acting hall or other valve D. It will thus be seen that there is no
open thoroughfare between the induction and eduction sides of the valve until the
bye-pass plug E is actually raised from its seat. In this construction a see
Figures 1 and 2 is a thoroughfare passing transversely through the stem of the
plug E. The longitudinal or axial thoroughfare a communicates with the passage a
at its upper end, and leads into a chamber E¹ formed in the bye-pass plug E.
From said chamber the thoroughfares a¹ a² lead into the bye-pass F, one on the
induction and the other on the eduction side of the valve. The supplemental ball
or other valve D is supported in place in the chamber E¹ by suitable means, for
example, by a screw piece E2 which is screwed into the lower end of the plug E.
The object of the said supplemental valve is as before stated to close the eduction
thoroughfare a² when the main valve is shut. Such closure is ensured by reason of
the greater pressure existing on the induction than on the eduction side of the
valve. While the ball or other valve D is serving to close the thoroughfare a², the
channels a, a are fully open thus affording a free communication between the valve
chamber C and the induction side of the valve, whereby any water which enters the
valve chamber is quite free to drain out by way of the said thoroughfares a, a', and
bye-pass F, and flow back into the steam pipe on the induction or pressure side of
the valve. It is thus obvious that condensed water cannot accumulate excessively
or become locked in the valve chamber as is possible in the constructions of valves
heretofore in use.
This valve is symmetrical about à vertical centre line and it follows therefore
that either side can be used as the induction side.
When the flow of steam is in the direction indicated by the arrow, Figure 1, the
ball D closes the passage a² and when it is in the reverse direction it closes the
passage a when the main valve is closed.
Preferably the hole a through the plug is made square or otherwise so shaped at
its lower end that the ball or other valve D cannot possibly close the same.
In some cases we place the automatic valve D in the plug seat or in the stem of
the plug, instead of in the plug itself the action in either case being the same as
that above described.
We may apply our invention to valves that have no plug attached to the valve
spindle as shown in Figure 3. In this construction, the plug seat shown in Figure 1
is replaced by a piece G provided with three thoroughfares a a' a leading from a
central chamber E' to the valve-chamber, and induction and eduction sides of the
valve. Dis the supplemental valve placed in said chamber E¹ for the purpose of
closing one or other of the passages a' a³ as, and for the purpose, above described
with reference to Figure 1. Gis a removable screw piece which allows of the
ball D being inserted and removed when required. The hole a is shown passing

page_text: through said piece G'. The bottom of the valve spindle H is grooved as shown
at Hto avoid blocking the hole when the main valve is shut down.
It will be seen that the valve chamber C is subject to the same pressure as the
ingress side of the valve when the valve is closed, and there is thus no tendency to
force the ingress valve disc from its seat.
In a modification of our invention we dispense with the automatic valve D above
described, and we substitute therefor a three-way cock I or its equivalent as
illustrated in Figures 4 to 7 which cock according to the position to which it is
turned will make communication simultaneously with the valve-chamber C and the
induction and eduction sides of the bye-pass F as shown in Figure 7 or with the
valve-chamber C and either the induction or the eduction side of the bye-pass as
shown in Figures 5 and 6 respectively. When it is desired to open the valve,
the attendant first turns the said three-way cock I into the position shown in
Figure 7 to make communication with the induction and eduction sides of the
bye-pass and the valve chamber so as to place the valve in equilibrium of pressure,
whereupon he can open the valve with comparative ease. After closing the
valve it is necessary to turn the three-way cock I so as to completely shut off
the eduction thoroughfare while however preserving a communication between
the valve-chamber and the induction side of the bye-pass to allow the said chamber.
to drain.
In lieu of a three-way cock we may sometimes employ a cock with an L-shaped
thoroughfare, or we may employ two taps so arranged in the passages a' and a²
that either can be closed as desired to accomplish the objects of our invention.
We preferably so arrange the handle of the cock I that it will act as a pointer
or indicator to show when the cock is turned to its proper position. In the con-
structions illustrated in Figures 4 and 5 the bye-pass may be placed at the bottom,
or at either side of the valve casing as may be desired.
It will be apparent that where these valves are used in water pipes our present
invention will lessen the danger of accident arising from the freezing of the water'
in the valve chamber.
Having now particularly described and ascertained the nature of our said
invention and in what manner the same is to be performed, we declare that what
we claim is :-
1. A parallel slide stop valve, having thoroughfares making communication
between the valve-chamber and the induction and eduction sides of the valve, in
combination with a ball or other valve which when the stop-valve is closed operates
automatically to close the eduction thoroughfare while allowing the induction
thoroughfare to remain open, for the purpose specified.
2. In a parallel slide stop valve, the combination with the three passages a a¹ a²,
of the ball or other valve D which can close either of the passages a' a² but not
both at the same time, substantially as, and for the purpose, specified.
3. A parallel slide stop valve having a bye-pass and a plug, provided with
the thoroughfares a, a', a² and the ball D, substantially as, and for the purpose,
specified.
4. The modification of our invention wherein we substitute for the automatically
operating valve, a cock to be operated by hand, substantially as, and for the
purpose, specified.
5. A stop valve constructed substantially as described with reference to Figures i
and 2, or to Figure 3, or to Figures 4 and 5 and operating as, and for the purpoзe,
specified.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicants.