Improvements in and relating to Safety-valves.
Year: 1890

page_text: The decision of the Comptroller-General, of the 26th day of April 1894, allowed,
under Section 18 of the Patents, &c. Act, 1883, an Amendment of this
Specification.
Date of Application, 29th Jan., 1890
Complete Specification Left, 12th Nov., 1890-Accepted, 13th Dec., 1890
PROVISIONAL SPECIFICATION.
Improvements in and relating to Safety-valves.
We, JOHN ADDY HOPKINSON and JOSEPH HOPKINSON, both of the firm of
J. Hopkinson & Co., of Huddersfield, in the County of York, Engineers, do hereby
declare the nature of this invention to be as follows:-
-
Our invention is designed to improve the construction and increase the
efficiency of safety-valves such as are known as Hopkinson's Patent Compound
Safety-valves.
In the said compound safety-valves, there is a hollow or annular valve in which
is arranged another valve fitting upon a seat thereon, so that a double discharge of
steam can take place. One of these valves is usually provided with suitable
weights within the boiler, and the other valve is weighted by means of a ball and
lever outside the boiler. The central or ball valve, that is to say, the valve
weighted inside the boiler is usually combined with a lever and a submerged
float so that, should the water in the boiler get below a predetermined level, the
said float and lever will move this valve away from its seat, and thus permit the
escape of steam from the boiler.
According to one part of our present invention, we provide improved means for
guiding the externally weighted or annular valve in its up-and-down movement and
for limiting the upward movement of the said valve and thus obviating any danger
of the said valves being blown out of their seats in case of breakage of the lever or
displacement of the weight thereon. We accomplish the desired results by the
employment of a device comprising a ring or annular piece having rods or pillars
extending upward therefrom and supporting at their upper ends a guide for the
spindle of the main valve. This guide for the valve-spindle is so arranged that it
also serves as a stop for limiting the upward movement of the valve for the
purpose above specified. The said rods or pillars are formed with surfaces which
guide the main valve in its up-and-down movement. The said device is, therefore,
a combined guide and stop for the valve. The said ring or annular piece
surrounds the main valve-seat and is secured in place by bolts or studs and nuts.
We prefer to form the seat for the annular valve on a flanged ring and to secure
this valve-seat in place by means of bolts or studs and nuts, which may, with
advantage, be those used for securing the said combined guide and stop.
.
We make the spindle of the main valve considerably shorter than heretofore,
and the said spindle is supported between the valve and the top of the dome or
cover of the casing by the aforesaid guide. Therefore the liability to bending of
the spindle and to breakage thereof by reason of defects in the metal or weakening
of the rod by corrosion, is greatly diminished.
In safety-valves of the kind or class above mentioned, the siphon-pipe or passage
for drawing off the water of condensation is connected to the waste-steam pipe, and

page_text: there is an annular space or channel around, and at a lower level than the valve-
seat, in which channel a considerable quantity of water must accumulate before it
escapes through the said siphon-pipe.
To avoid such accumulation of water in our improved safety-valve, we make the
part which receives the main valve-seat flush with the flange to which the dome is
secured, and we arrange a siphon-pipe or draw-off passage in the casing so that it
extends from the space beneath the dome to the exterior of the said casing. By
this arrangement, we ensure the outflow of all the water of condensation, there
being no space left in which the water can accumulate.
We provide the dome or top part of the casing with a suitable aperture which is
closed by a door or cover secured in such a manner that it can be readily removed
to permit the inspection of the valves, without the necessity for detaching the
waste-steam pipe from the casing. Or we provide the dome with a removable lid
or cover.
The central or supplementary valve is provided with a socket to receive the rod
or spindle to which the weight within the boiler is attached. This socket has
heretofore been formed on the valve immediately beneath the same, and we have
found that it obstructs, in some measure, the aperture for the passage of steam
through the annular valve, the socket being of large diameter and consequently
considerably reducing the area of the passage through the annular valve. To
overcome this objection, we, according to our present improvements, make the
central or supplementary valve with a stem or spindle of much smaller diameter
than the socket. This stem or spindle extends downward from the central valve
through the aperture of the annular valve, and has the socket formed or fixed
on its lower end a considerable distance below the said annular valve.
In our compound safety-valves as heretofore constructed, when the stand-pipe or
boiler-block for connecting the casing to the boiler, is made of cast metal, it has
formed thereon suitable lugs or other provision for receiving the support for the
fulcrum of the float-lever. When, however, a wrought iron or steel stand-pipe or
base-block has been used for connecting the casing to the boiler, it has been
necessary to drill and tap a hole in the boiler-shell and fix the said fulcrum-support
therein. We now provide an improved wrought iron or steel stand-pipe or base-
block for the purpose above specified, having secured thereto by welding, rivetting
or otherwise one or more angle-pieces or lugs to receive the aforesaid support for
the fulcrum of the float-lever.
When
In another modification of our invention, particularly advantageous where higher
pressures are used, we load the outside or annular valve by means of a suitable
spring, and the inside or ball valve by means of weights inside the boiler.
we employ a spring, we sometimes provide, in the lower end of the box or casing
containing the spring, a bush through which extends the stem or spindle of the
main valve, and which serves as a guide for the said valve and also as a stop for
limiting the upward movement thereof and thus preventing blowing of the said
valve out of its seat.
By our improvements above described, we overcome various objectionable
features which have been found, after many years' practice, to exist in our
compound safety-valves as heretofore constructed, and we greatly diminish the
danger of accidents arising from displacement of the weight or breakage of the
lever or spring, and obtain greater efficiency of discharge, whilst facilitating
the examination of the parts.
Dated this 29th day of January 1890
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicants.

page_text: Improvements in and relating to aby valve.
We, JOHN ADDY HOPKINSON and JOSEPH HOPKINSON, both of the firm of
J. Hopkinson & Co., of 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:-
Our invention is designed to improve the construction and increase the
efficiency of safety-valves of the type known as Hopkinson's Patent Compound
Safety-valves.
In the said compound safety-valves, there is a hollow or annular valve in which
is arranged another valve fitting upon a seat thereon. One of these valves is
usually loaded by weights within the boiler and the other valve is weighted by
means of a lever and weight outside the boiler. The central or ball-valve, that
is to say, the valve weighted inside the boiler is usually combined with a lever
one end of which carries a float and the other end a balance weight. The float is
submerged when the water in the boiler stands at or about the ordinary working
level, the action of the lever being such that when the water falls below a pre-
determined level the said central or ball-valve is raised from its seat and allows the
escape of steam, thereby calling the attendant's attention thereto.
Our present invention comprises various improvements in the said safety-valves,
which improvements are substantially as follow.
According to one part constituting the first improvement of our present invention
we provide improved means for guiding the externally weighted or annular valve in
its up-and-down movement, and for limiting the upward movement thereof, and thus
obviating any danger of the said valve being blown away in case of breakage of
the lever or displacement of the weight thereon.
Our second improvement relates to the spindle of the main valve and consists in so
constructing the valve casing as to permit of the use of a much shorter spindle than
heretofore, whereby we diminish the liability to bending or breakage of the said
spindle by reason of original defects in the metal or due to weakening of the rod by
corrosion.
Our third improvement consists in forming the part that receives the seat of the
main valve flush with the flange to which the dome is secured, and arranging a
syphon pipe or passage in the casing to draw off from the interior of the dome
all the water of condensation, thereby avoiding the accumulation of water in the
dome.
According to our fourth improvement, we form a suitable aperture in the dome or
upper part of the casing to provide for the inspection of the valves without entailing
the removal of the waste-steam pipe or the ball and lever. The said aperture is
provided with a door or cover.
Our fifth improvement consists in providing the central or dead-weight valve with
a comparatively long stem or spindle which passes through the aperture of the
annular valve withing causing any material obstruction therein, the socket to
which the valve is attached being formed on the lower end of the stem or spindle
at a considerable distance below the annular valve.
Our sixth improvement relates to the provision of a wrought or steel valve-bleek, to
which the valve casing is attached; having angle pieces of lugs-secured thereto-to
receive-the-support for the fulerum of the float lever, and
Our last improvement relates to a modification of our improved-safety-valve
particularly-adapted for very high pressures wherein a spring is employed for loading
the annular valve in lien of a lever-and-weight as heretofore. The spring-loaded
valve is in some cases moved to one-side of the dead weight valve instead of being

page_text: in the same axial line therewith in which arrangement there is not the same necessity
for so much overhead space in order to fix the valve-in-the-boiler.
In the accompanying drawings
Figure 1 is a vertical central section of a Hopkinson compound safety-valve
haring some of our present improvements hereinafter specified applied thereto.
Figure 2 is a plan, and
Figure 3 a vertical central section showing the valve guard and valve seat on an
enlarged scale.
Figure 4 is a side elevation of the dome.
Figure 5 is a vertical central section of a Hopkinson compound safety-valve
provided with other of our present improvements.
Figure 6 is a plan, and,
Figure 7 a vertical central section showing a slightly modified valve guard and
valve seat on an enlarged scale.
Figures S and 9 are vertical central sections of safety-valves-showing other of our
present improvements.
Like letters indicate corresponding parts in all the figures.
A is the annular externally loaded valve, B the central internally loaded valve;
C is the casing dome, and D the valve block.
a,
Referring to Figure 1, a is the seating block of the annular valve A secured
to the valve casing in any suitable or convenient manner. bis a valve guard shown
on an enlarged scale in Figures 2 and 3. The said guard consists of a ring bl
screw-threaded internally to fit a screw-threaded portion a' of the valve seat
and
having three or more upright bars 2 curved inwards at their upper ends and
connected by a boss 63 which is bored to receive the externally weighted valve
spindle c. The said vertical bars 2 act as guides for the annular valve, and the
eye in the boss serves to guide the valve spindle so that the valve is amply
secured against lateral displacement. Moreover the guard serves to limit the lift
of the valve by reason of the socket A¹ of the valve encountering the lower face
of the boss b³, and the height of the said guard is arranged to permit of any
desired lift. With a guard constructed as herein described, the valve is prevented
from being blown away should the spindle or lever be accidentally broken or the
weight become displaced thereon. Serious accidents have heretofore arisen from
this cause which would have been prevented by our improved valve guard.
In our improved valve we considerably reduce the height of the dome C in order
to shorten as much as possible the spindle c. It is obvious that with a long spindle
as heretofore used, there is increased risk of bending and breakage of the said
spindle especially when the valve is not set truly vertical, and when the spindle is
weakened by corrosion. This we obviate by reducing the height of the casing so
as to permit of the use of a spindle of the minimum of length, and this spindle
being also guided by the valve guard is thereby further strengthened and enabled
the better to resist a bending force.
For draining the dome of all condensation so as to keep the parts thoroughly
dry we form in the casing a passage d, and we so construct the parts that there
shall be no recess or cavity wherein water can lodge. That is to say we form the
bede for receiving the valve seat a flush with the face of the flange that receives
the dome thereby ensuring that there shall be no cavity around the said bed as in
the safety-valves heretofore constructed.
Our next improvement relates to the provision of an aperture in the dome or
upper part of the casing to facilitate inspection of the valve without necessitating
the removal of the waste-steam pipe or the ball and lever. g is the said aperture
which is closed by a door or cover g' that may be secured by bolts or set screws or
the like.
As heretofore constructed, the socket of the central or ball valve B to which
the spindle carrying the dead load is attached has been formed immediately
beneath the said central valve and we have found that the said socket materially
reduces the opening of the aperture in the annular valve through which it passes

page_text: and therefore restricts considerably the outlet opening for the steain.
We now
construct the said valve B with a long comparatively slender stem or spindle B¹
and form a socket B2, to which is attached the rod carrying the dead weight, at the
lower end of the said stem. By this means we improve the steam outlet opening
and increase the efficiency of the valve. In-some-eases-hawver-we-ma-ass
the-spindle-into-or-through-the-valve-and-seenre-the-same-by-a-serew-or-nut-or the
like so as to ensure a tight joint. In this case we dispense-with-the-socket-B²-and
also-maintain the maximum of area-for-the-esenpe-of-the-steam:
The
Our next improvement refers-to-the-valve block-and-is-shown-in-Figare
said valve block D is constructed of wrought iron or steel and is provided with
angle-pieces or lugs welded or rivetel or otherwise attached thereto. The said
Jugs are adapted to receive the support for the falerum of the float lever, anl
thereby obviate the necessity for drilling and tapping a hole in the boiler shell for
this purpose as has heretofore been the usual practice. The valve guard shown in
Figures 5, 6 and 7 is secured to the valve seat by bolts or set screws instead of
being screwed thereon as in the arrangement shown in Figures 2 and 3. It is
obvious that the construction of the said guard may be otherwise modified without
departing from the nature of our said invention.
In the modifiention of our-invention shown-in-Figure 3-we-provide fo-leading the
annular valve by means of n-spring instead of a lever-and-weight. For this purpose
we provide the valve easing with a-cover or cap-having-therein-a-bush-k;-forming
a guide for the valve spindle, and a-tabular-upward extension--enclosing the
spring m. The said upward extension-/-is-closed-at-the-top-by-a-eaver-n-seenred by
serews or bolts, having fixed therein-n-central-serew-threaded-bush-o-for-receiving the
the
serew-p-that-nets-to-compress-the-spring-For-testing-the-valva-wa-provide
following-or-equivalent-apparatas, that is to say, we mount-in-suitable-bearings-on
the-cover a short shaft- to which-is-secured-a-short-arm--adapted-to-engage-with-a
collar-s-of-a-tubalar-ensting s-mounted-on-the-upper-end-of-the-valve-spindle-c-and
enclosing-the-screw-p. The sleeve-s-is-connected-with-the-valve-spindle by means of
a-cotter-s-The-shaft 7 is also provided with a long-fixed-or-detachable-handle-by
which it may be partially rotated, thereby-neting-through-the-arm-r-and-sleeve-s-to
lift-the-main-valve-The-extent of lift-of-the-valve-is-limited-by-the-bush-k-whieh
answers-the same purpose as the boss-'-of-the-valve guard-in Figure 1.
It will be obvious that the valve-shown in Figure 3 will require-n-considerable
amount of overhead room in order that it may be properly fixed-in-the-boiler;-and-as
this is not always available we have provided a further-modification-which-does-ust
require-so-much overhead room-for-fixing.-In-this-modification-shown-in-igra-0
the externally loaded valve is removed-from-the-axial line-of the internally-loaded
valve and is provided with an independant-sent a'in -elose proximity-to-the-seat-of-the
internally loaded valve-and-a-channel-t-is-constructed in the valve easing to form-
communiention with the said externally weighted valve sufficient for the requirements
thereof -u-is-n-removable-cover-or-en-to-permit-of-the-insertion-and-withdrawal-of
the-internally londed valve and rod. u'-is-a-downwardly projecting lug from the
eover-u-serving-to limit the lift-of-the-valve. It is obvious-that-the-cover-u-is-easily
removable-to-termit-of-necess-to-the-valve-The-construction of the parts of this
valve-exeet-as-herein stated are-the-same as that shown in Figure-
In all the above modifications the screw-threads on the float rod required for the
purpose of adjusting the height of the Hoat, and the screw threads won the rod of
the central or ball valve which carries the nut w' against which the float lever a ts,
are preferably formed of brass cast on the said rods, and the nuts working on the
said threads are also preferably constructed of brass, thereby facilitating the
adjustment of the float and collar. In some eases we provide-the-cover-u-with-an
arrangement-for-lifting the internally-loaded-valve from its-seat.
In our improvements above described we overcome various objectionable features
which have been found, after many years' practice to exist in our compound safety
valves as hereto ore constructed, and we greatly diminish the danger of accidents
arising from displacement of the weight or breakage of the lever or spring, and

page_text: obtain greater efficiency of discharge whilst facilitating the examination of the
parts.
Having now particularly described and ascertained the nature of our said inven-
tion and in what manner the same is to be performed, we declare that what we
claim is :-
First. The berein described improvements in Hopkinson's compound safety-
valves whether used separately or in combination with each other for the purposes
specified.
Second. The compound safety-valve constructed substantially as above described
and illustrated in either of the forms or modifications shown in the accompanying
drawings, and operating as, and for the purposes specified.
Dated this 11th day of November. 1890.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, W.C., Agents for the Applicants.