Improvements in Automatic Furnace Damper Regulators for Hot Water Heating Systems or the like.
Year: 1892

page_text: Date of Application, 21st June, 1892-Accepted, 23rd July, 1892
COMPLETE SPECIFICATION.
Improvements in Automatic Furnace Damper Regulators for Hot
Water Heating Systems or the like.
A communication by LEVI FRANKLIN SMITH, of 2430, Thompson Street,
Philadelphia, in the State of Pennsylvania, United States of America,
Manufacturer.
I, WILLIAM PHILLIPS THOMPSON F.C.S., M.I.M.E., of the Agency for
Foreign Patent Solicitors, 6 Lord Street, Liverpool and 6 Bank Street Manchester
both in the County of Lancaster & 323 High Holborn in the County of
Middlesex, Civil Engineer, 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 :-
The object of this invention is to provide an automatically acting simple device
whereby the draughts or dampers of the furnace of a water heater, such as are
ordinarily used for heating houses may be so controlled, that, as the water in said
heater grows cool, the draughts or dampers will be opened to increase the heat of
the furnace; or, if such water becomes too hot, said draughts or dampers will be
closed so as to reduce the heat of the fire.
The invention therefore consists in an expansible pipe or rod arranged to be
heated by the return water from the radiators and connections between said rod or
pipe and the draughts or dampers, and in the novel construction and combination of
parts as will be fully understood from the annexed drawings and the following
general description, and which will be concisely stated in the claims.
Referring to the drawings by figures ;-
Figure 1 is a perspective view of a water heater with the invention attached.
Figure 2 is a detail view illustrating the expansion tube more fully hereinafter
described.
Figure 3 illustrates the expansion rod.
Figure 4 is a detail view of a damper.
Figure 5 is a detail.
A designates the body of the heater, B, B, the flow pipes, and C, c, c, the return
tubes. Upon the top of one return tube C is mounted a T-joint D; this makes th
connection between the said return tube and the joint d which connects with t
return pipe from the radiator. In the top of this T-joint is screwed a plug I
which is provided at its upper end with an ear e. An upright bar designated as G
is attached to a lug g on the side of the furnace by two adjusting nuts as illustrated.
It is essential to the proper working of the device that bar G be rigidly supported
in any suitable manner.
F is a horizontal lever, the rear end of which is pivoted to ear e, and it is also
fulcrumed near its rear end on the upper end of upright G as shown at f. The
fulcrum and pivot of said lever are close together so that an up and down movement
of the pivot gives a considerable throw to the front end of the lever.
The furnace damper H is constructed with an arm h which is connected by the
chain or rod I to the front end of lever F substantially as illustrated in the
drawing. The tube C should be made of copper or brass or some other metal
readily expanded by heat.
As soon as the water in the heater begins to warm it will pass up through the
flow tubes B to circulate through the radiators and come back to the heater
through the return pipes C, c, c, in the common and well known way.
As soon as the return water becomes so heated as to expand the tube C, the
latter necessarily lengthens; this tilts lever F on the pivot so that the front end
of the lever moves downward in proportion to the expansion of the said tube C.

page_text: This allows the damper H to partly or entirely close and thereby shuts off so
much air from the furnace. By shutting off the air, the heat of the fire is
diminished and the temperature of the water in the heater lowered.
On the other hand as the temperature of the water in the return tube C
decreases, the said tube will contract and in so doing tilt the long end of the
lever upward and cause the damper to open and let air in, to increase the heat
of the furnace. In this way the heat of the furnace may be regulated and become
uniform and so save a vast amount of labour and annoyance usually attendant upon
watching, managing and regulating the fire.
It will be observed that tube C forms a part of one of the return water pipes,
and the temperature of the water passing therethrough will more nearly approximate
the temperature of the water in the radiator above to which said tube is connected.
A part of the return service pipes and the working water current are thus
utilized to regulate the dampers.
To one of the flow tubes B may be secured a clip or bracket of any convenient
form. Upon this is pivoted a weighted oscillating lever J; the outer end of this
lever is connected by a wire or rod to the outer end of the lever F.
K designates a damper door hinged to the smoke pipe a as illustrated and
attached by a wire or rod k to the inner end of the lever J. L designates a disc
damper of the common and well known form, within the smoke pipe attached by a
rod to said damper K; which connection may be made adjustable as for instance
by means of a pin on said damper door that may be placed in adjusting holes in
said rod as indicated in Figure 5.
When the lever F is shifted by the means described and its outer end descends,
the weight will draw down the outer end of the lever J and the inner end of this
lever draws up the damper door by means of the rod k. The damper door as
before explained is connected by the rod 7 to the damper L, so that when said door
is opened, the said rod moving with it simultaneously closes the damper L, shutting
off the draught of the furnace and admitting cold air in the flue to cool the furnace
by decreasing the action of the fire, and when the door closes, the damper is opened
giving the furnace sufficient draught to increase the heat; thus the draught may
be automatically regulated.
In Figure 1, the cold air damper K is illustrated as a door operated by the rod,
but a circular damper having wings will serve equally well in some cases for the
same purpose. To this end a weighted arm N is attached to the movable plate as
illustrated in Figure 4 and is connected by a rod n to said lever F, so that when
the long end of said lever is tilted up, it will raise arm N, and when the long end of
said lever is tilted down, the weight will draw down the end of the lever N to
which it is attached.
With each motion of the lever N, the movable plate of the damper will be
shifted, and thus the entry of air may be controlled at this point. The door
damper as illustrated in Figure 1 is, however, preferred for this purpose.
Instead of the expansible tube C and as an equivalent therefor, the device as
shown in Figure 3 may be used.
This consists of an expansible metallic rod which is placed within one of the ordinary
return pipes c of the heater; said rod is firmly secured at its lower end to the
bottom of the pipe c and its upper end extends through a stuffing box on the top of
pipe c and terminates in an eye p. This pipe and rod P occupy the position of
pipe C and the eye p is pivoted to the rear end of lever F.
When the water in said heater begins to circulate through the radiators and back
again to the heater through the lower return pipes c as described, the water passing
through the pipe c will surround so much of the rod P as is in that pipe.
The rod should be made of brass or copper or some other metal easily expanded
by heat, so that when the water in said tube becomes hot, said rod will expand
lengthwise, and in so doing oscillate the lever F with the same effect on the
dampers etc., connected to said lever before described. It is preferable to
use the expansible tube.

page_text: It will be apparent from the foregoing that the return water from the radiators is.
utilised to regulate the heat of the furnace by the means described, in a simple and
efficient way.
While means are shown in Figure 1 for simultaneously regulating the draught
through both the ash pit and flue of the furnace, yet it is not necessary to regulate-
all the dampers, and it is proposed to regulate and use one or more of the dampers
shown as may be desired. In fact any form and arrangement of dampers may be
operated by the devices and the essential feature of the invention is the regulation
of the heat according to the temperature of the return water from the radiators, as
the temperature of the return water is the best indication of the temperature in the
building, and the devices can be so adjusted as to keep the return water at any
temperature desired.
It is also evident that the damper regulator herein described may be used
successfully with many other furnaces of forms differing from that herein described.
By attaching chains I and j to lever F at points nearer to or further from its
fulcrum, the extent of opening of dampers can be varied and regulated, or by
vertically adjusting rod G the same result can be attained.
Having now particularly described and ascertained the nature of the said inven-.
tion, and in what manner the same is to be performed, as communicated to me by
my foreign correspondent, I declare that what I claim is :
1. The combination in a hot water circulating system having in the discharge.
end of the return pipe a section, tube or rod of highly expansible material, of a
lever having a fixed fulcrum and suitably connected to the upper end of said section,.
tube or rod, and a damper for the furnace of the heater also connected to said lever,
substantially as described.
2. The combination in a hot water circulating system having in the discharge
end of the return pipe a section or tube of highly expansible material joined to the
main portion of the return pipe by a flexible coupling device, of a lever having a
fixed fulcrum and suitably connected to the upper end of said section or tube, and
a damper for the furnace of the heater also connected to said lever, substantially as
and for the purpose set forth.
3. The combination in a furnace of its flue, the damper in said flue, the door in
said flue above the damper but connected therewith so as to open the damper when
the door closes, and vice versa; with a tube or rod of expansible metal subjected to
the action of hot water, oscillating lever connected thereto, and the connections.
between said lever and said door, substantially as and for the purpose specified.
Dated this 20th day of June 1892.
WM. P. THOMPSON & Co.,
Agents for the Applicant.