Improvements in and relating to Safety Valves and their Accessories.
Year: 1895

page_text: Date of Application, 6th Mar., 1895
1omplete Specification Left, 6th Dec., 1895-Accepted, 1st Feb., 1896
PROVISIONAL SPECIFICATION.
Improvements in and relating to Safety Valves and their
Accessories.
1, GEORGE CHISHOLM, Junior of The Craigs, in the Town and County of
Stirling, North Britain Manufacturing Plumber do hereby declare the nature of
this invention to be as follows:-
It relates mainly to safety valves, inore especially those which are connected
with circulating boilers, high or low pressure, for domestic and other purposes; and
has for its chief objects;
1st to remove or reduce the liability of such a boiler bursting when in use
during frosty weather;
2nd to indicate, and afford an escapement, when there is too much or too little
water in the said boiler or water circulating system;
3rd to adapt such a boiler for being filled and used when some of its accessories
are frozen.
In carrying out this invention, one modification thereof comprises a cylindrical
metal barrel with upper and nether orifices, removeable covers, internal steam
shield and conical steam valve, sensitive water float, steam outlet indicator and
lever for operating it, together constituting the aforesaid safety valve consistently
with this modification.
Another modification thereof comprises, in addition to the foregoing mechanism,
a sensitive spring water valve adapted for operation by the rising of the aforesaid
float and constituting part of the said safety valve.
A further modification of this invention comprises steam outlet and manual
water filling devices in combination with the mechanism above named.
The following is a more particular description of these several modifications:
The barrel or cylinder of this valve has a hole or nozzle outlet at its base
adapting it for being united either to a boiler, pipe or other vessel. A steam
shield or buffer is fixed into or over the throat of the said nozzle and within the
cylinder. A sensitive water float occupies the upper part of the cylinder above
the said shield with room to rise or fall as required, sufficient space being left
around it for the passage of steam through the cylinder.
A conical valve is attached to the upper part of the float and a seat is made for
it in a removeable tubular part fixed to the cylinder top by screwing spring or
other means.
A lever is pivotted to the tubular part of this valve and linked at
one end to the upper part of the float and at the other to an indicator so that as
the float rises or falls within the cylinder it actuates through this lover the
indicator consisting of a tablet, dial or other suitable device visible upon the
outside of the cylinder.
A cover containing one or more perforations is fitted over this valve and lever
appliance so that when the water in the boiler, pipe or vessel is below the level of
the aforesaid float and becomes heated the steam produced escapes through the
Baid perforations thereby indicating the deficiency of water in the apparatus. In
the event of a sudden influx of water into a dry boiler when it is hot the steam
thus generated would find escapement at this perforated cover. When the
water fills the cylinder it raises the float and closes the aforesaid conical steam

page_text: The second modification before named consists in the combination with the
foregoing devices of a water escape valve, the former one constituting only a
steam escape. The aforesaid tubular conical valve seat in the cylinder top is,
under this modification, formed also as a conical valve fitting into a corresponding
seat in the cylinder top and pressed down into it by a spring regulated by means of
a screw in or upon the perforated cover before named. If the boiler or its accessories
become water bound by reason of frozen pipes or other causes the pressure
arising from the expansion of the water raises the flont compresses this spring
opens the water valve and gives vent to the water through the perforated cover.
In the third modification before named a manual filling appliance is attached to
or beneath the nozzle of the cylinder consisting of a trumpet shaped pipe having
an open mouth above the level of the perforated cover at which water may be
introduced into the boiler: the said pipe being fitted with a stop cock. The steam
escape pipe from the boiler or cistern is fitted with a branch escape pipo and stop
cock for emergency purposes so that the boiler may be filled when required at
this manual appliance and the steam allowed an escapement at the said brauch
pipe during such time or times as the ordinary supply pipes or cistern are
frozen:
This safety valve and its accessories are adapted for being fitted in close
proximity to the boiler or intermediate cistern or upon any of the pipes associated
therewith.
The emergency devices comprising the third modification hereof are designed
and adapted for combination with either or both of the first and second ones.
Dated this Fifth day of March 1895.
JOSEPH LOCKWOOD,
263 Argyle Street, Glasgow, Agent for the Applicaut.
COMPLETE DECIFICATION.
Improvements in and relating to Safety Valves and their
Accessories.
I, GEORGE CHISHOLM Junior of The Craige in the Town and County of
Stirling, North Britain Manufacturing Plumber, 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 :-
It relates mainly to safety valves, more especially those which are connected
with circulating boilers, high or low pressure, for domestic and other purposes; and
has for its chief objects;
1st to remove or reduce the liability of such a boiler bursting when in use
during frosty weather;
2nd to indicate, and afford an escapement when there is too much or too little
water in the said boiler or water circulating system;
3rd to adapt such a boiler for being filled and used when some of its accessories
are frozen.
lies.
The accompanying drawings will assist in making it clear wherein the invention
In carrying out this invention, one modification thereof comprises a cylindrical
metal barrel a with upper and nether orifices &, a removeable cover a internal
steam shield, 6" aud conical steam valve 6 sensitive water float B, & steam
outlet a indicator A. a' a' and lover 60 for operating it, together constituting the
aforesaid safety valve, see Fig. 4, consistently with this modification.
Another modification thereof see Fig. 5 comprises, in addition to the foregoing
devices, a sensitive spring water valve adapted for operation by the rising of
the aforesaid float B and constituting part of the said safety valve.
i

page_text: A further modification of this invention comprises steam outlet and manual
water filling devices in combination with the mechanism above named.
The following is a more particular description of these several modifications.
The barrel or cylinder B of this valve has a hole or nozzle a at its base
adapting it for being united either to a boiler, pipe d'or other vessel. A steam
shield or buffer is fixed into or over the throat of the said nozzle and within
the cylinder. A sensitive water float B occupies the upper part of the cylinder
above the said shield with room for it to rise and fall as required; sufficient space
being left around it for the passage of steam through the cylinder.
A conical valve & is attached to the upper part of the float B and a seat b is
made for it in a removeable tubular part a fixed to the cylinder top by screwing,
spring or other means: A lever 60 is pivotted to the tubalar part of this valve
and linked at one end, to the upper part of the float and at the other, 610 to an
indicator A, so that as the float B rises or falls within the cylinder a¹ it actuates
through this lever the indicator A consisting of a tablet, dial or other suitable
device проп the outside of the cylinder.
A cover a, containing one or more perforations a' is fitted over this 'valve and
lever appliance so that when the water in the boiler, pipe or vessel is below the
level of the aforesaid float B, and becomes heated the steam produced escapes
through the said perforations a' thereby indicating the deficiency of water in the
apparatus. In the event of a sudden influx of water into a dry boiler when it is
hot the steam thus generated would find escapement at this perforated cover a°.
When the water fills the cylinder a' it raises the float B and closes the aforesaid
conical valve ³, b.
The second modification boforenamed consists in the combination with the
foregoing devices of a water escape valve 6, the former one, &, constituting only
a steam escape.
The aforesaid tubular conical valve seat 6, 6º in the cylinder
top a' is, under this modification formed also as a conical valve, fitting into a
corresponding seat in the cylinder top a' and pressed down into it by a spring b
regulated by means of a scrow in or upon the perforated cover a beforenamed.
If the boiler For its accessories C, D, E, become water bound by reason of
frozen pipes or other causes the pressure arising from the expansion of the water
raises the float B compresses this spring b' opens the water valve 6' and gives vent
to the water through the perforated cover a°.
In the third modification before named a manual filling appliance C, c¹³ is
attached to or beneath the nozzle a' of the cylinder a' consisting of a trumpet
shaped pipe C having an open mouth above the level of the perforated cover a®
at which water may be introduced into the boiler; the said pipe C being fitted
with a stop cock c'. The steam escape pipe from the boiler F or cistern E is
fitted with a branch escape pipe D and stop cock d' for emergency purposes BO
that the boiler F may be filled when required at this manual appliance C, cand
the steam allowed an escapement at the said branch pipe during such time or times
as the ordinary supply pipes d' or cistern are frozen.
This safety valve and its accessories are adapted for being fitted in close
proximity to the boiler F or intermediate cistern E or upon any of the pipes d
associated therewith.
The emergency devices comprising the third modification hereof are designed
and adapted for combination with either or both of the first and second ones.
This invention will be better understood if reference is made to the accom-
panying drawings in which :-
Figure 1 is an external view in elevation shewing the first named modification
thereof;
Figure 2 is an external view in elevation shewing the second and third named
modifications thereof in combination :
Figure 3 is an external view in elevation shewing the second and third named
modifications of this invention in combination with domestic hot water circulating
appliances:

page_text: Figure 4 is a sectional view of the devices constituting the first named modifica-
tion thereof:
Figure 5 is a sectional view of the devices constituting the second named
modifications thereof.
Similar letters of reference and numerals throughout the drawings indicate
corresponding parts.
Referring to the drawings the parts marked A. and a' Figs. 1 to 5 represent an
indicator visible on the outside of the valve casing or cylinder a' and the parts
marked a are holes for escapement of water or steam: a is a nozzle for attach-
ment to a boiler, pipe or other vessel, it is adapted for being screw threaded either
internally or externally. In Fig. 2 the holes a' aro not visible externally the
screwed cap a' presses down the spring b' Fig. 5 of the water valve & in propor-
tion to the normal pressure required in the apparatus with which it is associated.
The guide rod, &, acting as a support for the spring 6' is shewn in the drawings
with a sent 6 covering the escapement pipe of the steam valve . This steam
valve, is fixed to a very sensitive hollow float B which is operated by water
only it rests upon a steam shield or buffer b² and has a vertical rod 68 working
freely through : it is also connected by the rod 6° with the arm marked 610
pivotted above 6 for actuating the indicator A which is connected to it by the
link b. The steam shield 67 is supported from the interior of the cylinder a' by
any kind of open bracketwork such as " which allows steam to pass up through
the nozzle a into the cylinder. The cylinder a' should always be full of water
when the apparatus is in use and the float B raised until it closes the steam valve ¿ª
and shows by the indicator A that the circulating apparatus is acting properly.
If the pressure of water in the apparatus increases excessively from any cause its
effect upon the float B is to raise it until the water valve Fig. 5 is lifted from its
seat in the cover a' and water escapes through the holes a' in the cover a, thereby
indicating to any person present the necessity for attention and at the same time
reducing the water pressure.
"
When the water sinks so low in the apparatus that the light sensitive float B
descends and rests upon its support b' as shewn in Fig. 5 the steam valve opens
the indicator A is moved and exhibits warning words such as the word "danger
Fig. 1, also directions what ought to be done. If nothing is done under such
circumstances to remedy the evil and the water becomes exhausted from the boiler
and an influx of cold water then enters it whilst it is heated the steam fiuds escape-
ment through this safety valve and blows off at the holes a' until the water rises
again sufficiently to fill the cylinder a' and lift the float B as shewn in Fig. 4,
closing the steain valve 6 and restoring the indicator A to its normal condition as
shown in Fig. 2.
In Fig. 5 the spring b₁ subject to variations of tension through the screwed
cap a imparts the required resistance to water pressure.
In Figure 2 a device is shewn whereby in emergency cases water is filled into a
water circulating apparatus such as herein described by manual appliances. In
the event of the automatic water supply to a boiler being cut off by frost or
other causes water is poured into it through the nozzle a³ by means of the pipe C
Fig. 2, being furnished with a stop cock and funnel or other kind of mouthpiece
for receiving the impromptu supply.
In Figure 3 a similar contrivance is represented whereby an emergency water
service is afforded to a circulating hot water apparatus during such times as its
automatic water service is, from any cause, interrupted and by which means the
circulating cistern E is prevented from bursting or becoming steam bound when
its vent pipe d' is choked or frozen: the pipe C, stop cock and funnel Fig. 3
are for the same purpose as already explained concerning them with reforence to
Fig. 2, and the pipe D with stop cock d' are for affording an escapement for the
steam contained in the cistern E when the pipe is choked. In this Fig. 3 a
domestic hot water circulating apparatus is shewn with boiler F, circulating
cistern E, cold water feed pipe d³ for the boiler, a hot water pipe d to cistern E,

page_text: circulating piped from cistern E to the boiler F and a steam vent pipe. The
pipes which are most liable to become choked in frosty weather are the upper
parts of and d. If the water contained in the piped which supplies the
boiler F becomes frozen whilst the fire is kept burning the boiler becomes dry and
bursts when the ice is thawed in and the cold water flows into the dry hot boiler.
If any boiler in such circumstances is furnished with this improved safety valve
the steam valve 6 would then be open aud by affording an escapement for the steam
thus generated, prevent the boiler bursting.
If, in addition to being furnished with the said safety valve the pipe C, c'c,
Fig. 2, is affixed to it the boiler and pipes d³, d and can be kept always full of
water up to the level of c' and thereby prevent any liability of the boiler F
bursting.
The condensed stoam in the pipe often freezes aud endangers the bursting of
the cistern E or boiler F, and the devices C, c', o fixed to d', and D, ' fixed to d
are emergency manual appliances for preventing the possibility of an explosion
occurring from such causes, and enabling the hot water circulating apparatus to
continue in operation when the pipes dor d' aro choked with ice or otherwise
incapacitated for use. By frequently filling in water at the funnel * and keeping
the steam cock & open such an apparatus as that which is shewn in Fig. 3 may be
kept in constant and safe use.
The devices C, c', c³, D and d' Fig. 3 are sufficient of themselves to prevent
explosion without the safety valve G provided that the persons in charge of the
apparatus are attentive to its condition: the addition of this safety valve in either
of its modificatious affords the greatest security against an explosion as it presents.
by the indicator A au inevitable warning that the water is getting dangerously low
in the apparatus.
'
The indicator A consists in part of one or more fixed, non-transparent bands, a
Figs. 1 and 2 and intermediate openings or transparent parts a: these bands act
as a screen for a tablet or label suspended in a recessed portion of the cylinder
behind them. Upon the said tablet or label are words of warning and directions
how to act; when the water siuks below the steam shield the float B subsides
upon it and as the float falls it raises the label which is suspended to the lover
arm and brings the words of warning into sight as shewn in Fig. 1. This screen
is sometimes composed of metal bands and at others of a piece of glass with non-
transparent bands a' upon it for hiding the words when they are not required.
The tablet or label moves up and down in the recessed part of the cylinders
exterior and the hit and miss screen forms a barricade or fence to enclose it.
I am aware that previous to my invention water flcats have been combined with
steam engine boilers both for the purpose of indicating the need of water therein
and in some cases for operating the valves for supplying the deficiency: also that
hollow floats have been employed for the purpose of actuating steam and other
valves automatically as they were raised and lowered by means of water contained
in a vessel: also that steam escapemeut valves have been combined with domestic
and other circulating boilers wherein the valves have been weighted or pressed
down by springs, it will therefore be understood that I do not claim any of these
things broadly as my invention.
Having now particularly described and ascertained the nature of my said inveu-
tion and in what manner the same is to be performed, I declare that what I
claim is :-
First. In a safety valve for a hot water pressure boiler the combination there-
with of the cylinder a', float B, valve and indicator A, a', as all substantially as
herein described with reference to Figs. 1 and 4 of the drawings or any mere
modification thereof for the purposes specified.
Second. In a safety valve for a hot water pressure boiler the combination thero-
with of the cylinder a', float B, valves and 6, indicator A, a', a³, spring b' and

page_text: outlets a³, all substantially as herein described with reference to the drawings, or
any mere modification thereof for the purposes specified.
Third. In a safety valve for a hot water circulating pipe or apparatus the
combination therewith of the cylinder a', flont B, valve and indicator A, 47, a³
all substantially as herein described with reference to Figs. 1 and 4 of the
drawings or any mere modification thereof for the purposes specified.
Fourth. In a safety valve for a hot water circulating pipe or apparatus the
combination therewith of the cylinder a', float B, valves ',, indicator A, a', a³,
spring and outlets a' all substantially as herein described with reference to the
drawings or any mere medification thereof for the purposes specified.
Fifth. In a safety valve for a hot water circulating apparatus the combination
therewith of the pipe C, c', c², all substantially as herein described with reference to
the drawings or any of them, or any mere modification thereof for the purposes
specified.
Sixth. In a hot water circulating apparatus the combination therewith of the
devices C, o, c, all substantially as herein described with reference to the
drawings or any mere modification thereof for the purposes specified.
Seventh. In a hot water circulating apparatus the combination therewith of the
devices C, c', c³, and D, d' all substantially as herein described and drawn or any
mere modification thereof for the purposes specified.
Eighth. In a safety valve for a hot water circulating apparatus the combination
therewith of the hit and miss screened indicator A, a', a, all substantially as
herein described with reference to the drawings or any mere modification thereof
for the purpose specified.
Dated this Fifth day of December 1895.
JOSEPH LOCKWOOD,
263 Argyle Street, Glasgow, Agent for the Applicant.
JOSEPH LOCKWOOD,
263 Argyle Street, Glasgow, Agent for the Applicant.