Improvements in Apparatus for Regulating or Controlling the Temperature in Buildings.
Year: 1889

page_text: Date of Application, 10th Dec., 1889-Accepted, 1st Feb., 1890
COMPLETE SPECIFICATION.
Improvements in Apparatus for Regulating or Controlling the
Temperature in Buildings.
I, WILLIAM PENN POWERS, of No. 125 S 5th Street, La Crosse, Wisconsin, United
States of America, Mechanical Engineer, do hereby declare the nature of this inven-
tion and in what manner the same is to be performed, to be particularly described and
ascertained in and by the following statement :-
My invention has for its object to provide means whereby the temperature of
various rooms in a building is automatically controlled.
In carrying out my invention I make use of the expansive force of a fluid vaporiz-
able at a degree of heat approximating that which it is desired to maintain in the
building, said fluid being confined in a vessel having one or more flexible metallic
walls and located in one of the rooms to be heated, the movement of the said wall
being utilized to operate by means of interposed air or other fluid, a damper or
transom window or fanlight actuating device. This device I may combine with
means for closing the damper of a furnace by the generation of steam in an ordinary
low pressure steam heating boiler or in a supplemental boiler located within and heated
by the water of a hot water heating system and operating by reason of the difference
in pressure on the water of the main boiler and the water contained in the supplemental
boiler.
In the accompanying drawings
Figure 1 is a side elevation of my improved heating appliances, comprising a
furnace and hot water heating boiler, located say in the basement of the building,
showing a heating coil on an upper floor and my thermostat applied thereto; this
device may also be applied to the control of a low pressure steam heating apparatus.
Figure 2 is an elevation partly in vertical section, of the damper operating
device.
Figure 3 is a central vertical section of the thermostat which is shown in Figure 1
located in the same apartment with the heating coils.
and
Figure 4 is a similar view showing a modified construction of the thermostat,
Figure 5 is a sectional detailed view of the enlargement in pipe D and showing
the supplemental boiler or steam generator, hereinafter described.
Referring to the drawings, A indicates the hot water boiler, B a pipe leading
therefrom to the radiator C, D an enlargement in pipe B enclosing a vessel or a
steam generating boiler D1 (see Figure 5) containing a body of water to be
heated by the water of the circulation and communicating by a pipe b, with a
chamber E, formed by enclosing wall F and diaphragm G as shown in Figure 2.
His a second diaphragm placed above diaphragm G and secured by means of a
curved wall I and bolts i, which are passed through the margins of both of the
enclosing walls and of the diaphragm as shown in Figure 2. A piston rod J is
seated on the diaphragm H and its upper end is secured to a lever K pivoted at k
to an arm L, projected upwardly from the walls of the chambers described.
One end of this pivoted lever will be provided with a weight M and the other
will be connected by chains with the damper N. By reference to Figure 2 it will
be seen that the diaphragms G and H are separate except around the margin
between the confining plates with a space or chamber h, between them, for a
purpose presently described. The piston rod J as shown in Figure 2 has its
lower end bifurcated and a disc j attached to the bottoms of these bifurcations, the
disc being secured to the diaphragm H by means of a bolt Q having a nut o.
This bolt has an aperture P through it which communicates at one end with the
space h, between the diaphragms and at the other with a pipe Q having therein
a.valve q.
Pipe Q is carried upwardly into a room whose temperature. it is

page_text: desired to regulate and there communicates with a thermostat, indicated in Figure 1
by the letter R, and shown in sectional elevation in Figure 3. This thermostat
consists of a. vessel divided into two compartments or chambers, by a flexible
metallic diaphragm U. One of said chambers marked S is intended to contain
a,fluid, vaporizable at about the temperature which it is desired to maintain in the
room to be heated. Said chamber is smaller than the fellow chamber T, the
diaphragm U, being curved as shown and under tension caused by the spring of
the metal or by suitable coiled or flat springs, whereby it will have a tendency to
enlarge the chamber containing the volatile fluid and thereby produce a partial
vacuum in said chamber, which being sealed, the pressure on the fluid therein is
relieved and the boiling point of the fluid is lowered in accordance with the well
known law that the boiling point of a liquid is determined by the pressure upon its
surface; and thereby I am enabled to secure action of the diaphragm at a tem-
perature lower than the normal boiling point of the volatile liquid. The liquid is
introduced into chamber S through a pipe s, which is then sealed, and a ring r
serves to suspend the vessel on the wall of a room when it is desired to employ a
flexible pipe or tube to connect the thermostat with the damper operating device."
The air or other fluid included in chamber T and pipe Q forms a fluid piston whereby.
the movement of the flexible wall of chamber S is communicated to the diaphragm H
and thence by the means described to the damper or transom.
The operation of the device is as follows:-
When the temperature in the room in which the vessel R is placed reaches a point
high enough to vaporize the liquid contained in the chamber S the expansion or
vaporization of said liquid will operate to force the diaphragm U inwardly, or toward
the opposite wall of the chamber, and thereby compress the air in the chamber T.
This air seeking escape, will be forced through the connecting tube Q and into the
space between the two diaphragms G and H of the regulating device and in so doing
will distend the upper diaphragm sufficiently to rock the lever and permit the damper
to close, thus shutting off the draught and lowering the temperature of the room. As
the temperature is lowered in the room, the vapour formed in the chamber S condenses,
the diaphragm U relaxes, the air flows back into the chamber T and the lever, acting
under the influence of the weight and the pressure of the air upon diaphragm H
approximates towards its normal position, thus opening the damper again and per-
mitting the combustion in the furnace to proceed.
The damper is also regulated at the boiling point of the water enclosed in the
'supplemental boiler at B. When steam is generated in said boiler, it passes through
pipe b to the chamber E and expanding therein, flexes both diaphragus and operates
the damper rods. When used in connection with a low pressure steam heating boiler
the pipe is connected directly with the boiler, preferably below the water line, the
steam pressure in the boiler operating in the same manner to raise both diaphragms
and close the damper, the chamber D and the supplemental boiler D¹ being
omitted.
It is obvious that this device may be applied to open or close a transom-window
or fanlight or operate other ventilators the only change necessary to adapt it to
operate a transom-window or fanlight being to connect the lever K with the operating
rod of the transom-window or fanlight.
I prefer to make vessel R much larger than the one to which the actuating lever
is connected and I obtain an important result thereby. As is well known the move-
ment of a metallic diaphragm. is comparatively limited and none other than a
metallic diaphragm can be used in contact with volatile liquids, as such liquids are
active solvents of rubber and similar substances, and hence in the thermostat, I
employ a metallic diaphragm.
In the lever actuating device I use a rubber diaphragm, as it is in contact with air
and water only, and this diaphragm being smaller and more flexible than the other, a
slight movement of the diaphragm of the thermostat, causes a considerable movement
of the diaphragm of the damper actuating device. Thus, where one diaphragm has
four times the area of the other, a. movement of one half inch in the first will be

page_text: magnified into a movement of two inches in the second, through the interposed
column of air or other fluid.
It is obvious that modifications may be made of the forms of construction here
described. As for example in the construction of the thermostat and I have shown
in Figure 4 such a modification. In this Figure, the chamber S is formed by two
corrugated diaphragms, both of which are flexible their margins being secured
together and enclosed within chamber T. Both of said diaphragms are distended by
the vaporization of the fluid in chamber S, and operate to force the air out of
chamber T.
Jt is also obvious that the thermostat may be used with a damper or transom window
or fanlight regulating device having only one diaphragm as H for example, and the
provisions for actuating the damper may be omitted. They are conveniently com-
bined however, and it may be found convenient to use both devices in combination.
The device above described is adapted to control the temperature within a very
narrow range, and I regard as the chief improvement, the provisions for utilizing an
air or other fluid piston interposed between the thermostat, and the damper actuating
mechanism, as this improvement renders it easy to control the damper of a furnace
located at a distance from the thermostat without the intervention of rods or other
connecting devices, the use of which is attended with many objections.
By means of this combination of the two diaphragms with the fluid piston interposed,
I am able to make a rigid connection of the operating devices, with the smaller and
more elastic of the two, whereas, if such connection were made direct to the metallic
diaphragm at any particular point (as the centre) the diaphragm would soon be
destroyed by its action under pressure, the pressure being exerted upon all its surface,
while the resistance is only at one point, where the piston is connected. But by my
method the pressure is equal upon each side of the metallic diaphragın and distributed
over every point of the same, thus making it practicable to use a very light and
sensitive diaphragm and still have it durable and lasting. By means of this com-
bination I am also able to increase the movement of the piston, as compared with that
of the metallic diaphragm by making the piston diaphragm relatively smaller than the
other.
Having now particularly described and ascertained the nature of my said inven-
tion and in what manner the same is to be performed I declare that what I
claim is :-
First In a beat controlling device the combination with a thermostat having a
vaporizing chamber to contain a volatile liquid said chamber having one or more
flexible walls adapted to be flexed by the volatilization of the liquid, a second chamber
and a pipe leading therefrom whereby to confine a body of air or other fluid in
contact with said flexible wall, and a pressure chamber with which said pipe com-
municates and having a diaphragm or other piston and suitable operating devices
actuated by said diaphragm, whereby the movement of the wall of the vaporizing
chamber is transmitted through the interposed air or other fluid column, to the
diaphragm of the pressure chamber, substantially as described.
Second-In a heat regulating apparatus, a double diaphragm composed of two
elastic sheets, one of which forms one wall of a pressure chamber to operate by
pressure of steam the other designed to operate by a fluid pressure transmitted
through a pipe and caused by the volatilization of a liquid vaporizing at about the
temperature sought to be maintained the diaphragms being so arranged that the
effect desired is produced by the action of either cause independently of the other,
substantially as described.
Third In a heat regulating device, a vaporizing chamber to contain a volatile
liquid, a movable side or wall normally under tension, such tension tending to
enlarge the vaporizing chamber and thereby produce a lowering of the pressure
upon the contents thereof and consequently a lower point of vaporization for the
purpose of securing action at a lesser degree of heat, as, and for the purpose
specified,

page_text: Fourth In a heat controlling device, the combination with a thermostat, of a
damper or ventilator actuating device, comprising two diaphragms secured within a
pressure chamber and having a space between their opposing surfaces, a tube com-
municating with said space and with the thermostat and a steam generating boiler
communicating with the chamber below the diaphragms, substantially as described.
Dated this 10th day of December 1889.
HASELTINE, LAKE & Co.,
45, Southampton Buildings, London, Agents for the Applicant.