Improvements in Water Heaters.
Year: 1896

page_text: Improvements in Water Heaters.
ANDREW SWEET 102 Hampstead Road N.W. Manufacturing Ironmonger do hereby
declare the nature of this invention to be as follows:-
My improvements relate to water heaters heated by gas of the kind known as
instantaneous water heaters-or to vessels or boilers which contain a quantity of water
and after that is used any further quantity drawn is heated as it passes through the
heater, this I call a combination heater, or I apply my improvement to a static heater
solely i.e. a boiler containing a given quantity of water heated by a small burner-
my improvements being in combination with the above to automatically regulate or
control the supply of gas to the burner or field of combination under the following
conditions-for the purpose of either automatically determining the maximum
temperature of the water it is desirable to heat or to preserve the boiler or heater
from injury by abnormal pressure.
This object I attain by utilising the heat of the exterior of the boiler or heater, or
by the steam generated therein if the water is to be maintained at the temperature
of 2120° Fah.
The primary motion necessary to regulate or control the temperature is obtained
by the differential expansive co-efficiency of two metal bars or wires so arranged that
a multiplying effect or motion is obtained to open or close the orifice through which
the air or gas passes on its way to the field of combustion. This compound bar or
wire for economic reasons I make of steel and brass which give a differential linear
expansion of 1 on 532 to 1 on 926-but I do not confine myself to these 2 metals as
the co-efficiency of other metals or materials may give greater motion, such as brass
and glass which give a differential linear expansion under the same unit of heat of
1 on 532 to 1 on 1160-or platinum and silver which under the same conditions of
increase in temperature elongate as 1 on 1166 to 1 on 523.
This compound bar or wire forming part of my invention may be of any suitable
configuration for the purpose of engaging under conditions of increase of temperature
the mechanism in the body of the valve i.e. that part containing the orifice through
which the gas or air passes on its way to the field of combustion, where gas is passing
I use a rubber diaphragm, tube, sleeve or by preference a stuffing box to prevent
the gas escaping into the atmosphere before reaching the field of combustion.
By these combinations I make an effectual automatic valve which cannot under the
most adverse conditions be the means of passing gas into a water main to its
detriment contamination as in those hitherto in use.

page_text: Improvements in Water Heaters.
ANDREW SWEET 102 Hampstead Road London N.W. Manufacturing Ironmonger
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:-
My improvements relate to water heaters heated by gas of the kind known as
instaneous water heaters-or to vessels or boilers which contain a quantity of water
and after that is used any further quantity is heated as it passes through the heater
this I call a combination heater-or to a static heater solely, i.e. a boiler containing
a given quantity of water heated by a small burner or comparatively small-my
improvements being in combination with the above to automatically regulate or
control the supply of gas to the burner or field of combustion under the following
conditions.
For the purpose of either automatically determining the maximum temperature
of the water it is desired to heat or to preserve the boiler or heater from injury by
abnormal heat or pressure.
This object I attain by utilising the heat of the exterior of the boiler or heater-
by the insertion of a tube into the heater-or by the steam generated therein if the
water is to be maintained at the temperature of 212° Fah. The primary motion
necessary to regulate or control the temperature is obtained by the differential
expansive co-efficiency of 2 metal bars or wires so arranged that a multiplying
effect or motion is obtained to open regulate or close the orifice through which the
air or gas passes on its way to the field of combustion this compound bar or wire for
economic reasons I make of steel and brass which give a differential linear expansion
under the same increase of temperature of 1 in 532 to 1 in 926 but I do not confine
myself to these two metals as the co-efficiency of other metals or materials may
give greater motion, such for instance as brass and glass which give a differential
linear expansion under the same unit of heat of 1 in 532 to 1 in 1160 or platinum
and silver which under the same conditions of increase in temperature elongate as
1 in 1166 to 1 in 523.
This compound bar forming part of my invention may be of any suitable
configuration for the purpose of engaging under the condition of increase of
temperature the mechanism of the valve i.e. that part containing the orifice through
which the gas or air passes on its way to the field of combustion, when luminous
gas is used as the heating medium I use a rubber diaphragm, tube, or sleeve or by
preference a stuffing box so preventing the gas escaping into the atmosphere before
reaching the field of combustion.
By these combinations I make an effectual automatic valve which cannot under the
most adverse conditions be the means of passing gas into a water main to its detriment
and contamination as in those hitherto in use.
The two sheets of drawings herewith taken with the explanation more fully
illustrate and explain the principle and an effectual method of practically carrying
out the same. Sheet No. 1 Fig. 1 represents an automatic controlling valve applied
to a glue pot, in this case the temperature of the water in the outer chamber B is
required to be kept at 180° Fah. A illustrates the glue pot B the water chamber
CD the compound bar C being the brass strip and D the iron strip or mild steel,
these being firmly bound together & forming one bar, a suitable size for these strips
is half an inch wide and from six inches to 1 foot long and of 18 guage in thickness-
this bar is encased in a tube and let into the water chamber B and firmly attached at
the point K E is the regulating screw, and G F shows the valve, the bar co-operates

page_text: with also the class of burner best adapted for regulation when an atmospheric burner
is used.
The working is as follows, on the water in the chamber B being heated the
compound bar also becomes heated when by its differential expansion .e. the lined
expansion of the brass slip C being greater than the slip D the rod H is depressed
causing the cone valve F to drop into the gas outlet G, thus more or less closing the
gas way as the gas passes to the field of combustion L.
Section 1 on the same sheet shows in plan the field of combustion K this class of
burner can be used on any apparatus but where non-atmospheric burners are used
a different valve is necessary which will be more particularly explained as in Fig. 2.
Fig. 2 shows the application when the water in vessel is required to be kept actually
boiling in this case the compound bar is heated by the steam only as it passes out of
the vessel from the spout, C D is the compound har, D being the brass slip and C being
the iron slip the two together forming the compound bar E is the regulating screw
O is the valve F. F are luminous burners, the construction of this valve will be more
readily understood by referring to Fig. 4 on Sheet 2 where it is given in larger
section C being the inlet to the field of combustion and D the outlet F the closing
seat showing a small bye pass.
Sheet 2 Fig. 3 shows the application of this regulating or governing principle to
what I have called a combination heater i.e. where a given quantity of water in a
vessel is heated and maintained at a set temperature and after this quantity is drawn
off a continuous flow of hot or warm water may be obtained of indefinite quantity,
under such a condition it is essential that immediately a small quantity of water is
drawn off that the controlling or lessening of the gas way should cease, the compound
bar is therefore placed close to the bottom of the heater.
F is the vessel charged with water, A is the inlet, B is the compound har C the
valve G the point at which the bar is firmly attached P the outlet-to draw water
from the heater, the gas being alight. Open the inlet A when the hot water will
flow from the outlet P the cold water taking the place of that drawn out falls to the
bottom and cools the bar B thus opening the gas way, the gas way being thus kept
open all the time water is being withdrawn and remaining open until the body of
water in the vessel F again attains the set temperature.
Fig. 5 shows an application of the bar where the cooling is slow, the cooling being
caused by radiation only, a convenient way of applying the bar in such a case is on
the outside of the vessel.
CD is the bar G the fixed point.
Having now particularly described and ascertained the nature of my said
invention and in what manner the same may be performed, I declare that what I
claim is:
1. The lineal differential co-efficient expansion of 2 metals heated by water
arranged to automatically determine the maximum temperature of the aforesaid
water.
2. The lineal differential co-efficient expansion of 2 metals in combination with
a valve as set forth in the drawings herewith.
3. The lineal differential co-efficient expansion of 2 metals in combination with a
valve as set forth in the drawings herewith to economise gas in heating water.
4. The lineal differential co-efficient expansion of 2 metals in combination with a
valve as set forth in Sheet 2 Fig. 4 to regulate the combustion of gas.
May 13th 1907