Title:
Heater
United States Patent 2160264


Abstract:
This invention relates to heaters and more particularly to circulating heaters adapted to be placed in a room or other enclosed space to heat the air therein. One of the objects of the invention is to provide a heater in which the parts may be readily assembled and disassembled for installation...



Inventors:
Furlong, Francis A.
Application Number:
US5555335A
Publication Date:
05/30/1939
Filing Date:
12/21/1935
Assignee:
AUTOGAS CORP
Primary Class:
Other Classes:
126/99D, 126/116A, D23/329
International Classes:
F24H3/00
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Description:

This invention relates to heaters and more particularly to circulating heaters adapted to be placed in a room or other enclosed space to heat the air therein.

One of the objects of the invention is to provide a heater in which the parts may be readily assembled and disassembled for installation or repair and in which heat will be transferred to the space to be heated with a high degree of efficiency.

Another object is to provide an encased heater in which the casing will remain relatively cool.

One arrangement for accomplishing the above and other objects includes a casing having an air inlet opening adjacent its bottom and an opening adjacent its top through which a heat transfer unit may be inserted. A burner is mounted in the lower portion of the casing and the unit includes a passage for the products of combustion of the burner which may be connected to a conventional flue. The unit also includes air passages surrounding the combustion space and spaced from the sides of the casing to provide supplemental air passages, air circulating through said supplemental passages conducting heat away from the casing walls and keeping the casing relatively cool. Preferably baffles are provided to direct the heated air substantially horizontally out the outlet.

In one illustrated embodiment of the invention the flue extends upwardly and is surrounded by an extension of the casing which may be formed integral or as a separate casing. The extension is provided with inlet and outlet openings so that air may circulate around the flue and be heated by contact therewith.

Other objects, advantages and novel features including novel subcombinations and structural elements will be apparent from the following description when read in connection with the accompanying drawings, in which: Figures 1 and 2 are perspective front and end views of a heater embodying the invention; Figure 3 is a perspective view of the heater of Figures 1 and 2 with parts broken away; Figure 4 is a partial section of the heater of Figures 1 and 2 showing the flue connection; Figure 5 is a transverse section of the heater of Figures 1 and 2; Figure 6 is a view similar to Figure 5 showing a modified construction; Figure 7 is a diagrammatic sectional view showing the burner control system; Figures 8 and 9 are front and rear perspective views of a modified form of heater; Figure 10 is a perspective similar to Figure 8 with parts broken away; Figure 11 is a perspective view of the heat transfer unit and burner with parts broken away; and Figure 12 is a partial perspective view similar to Figure 10 showing the burner in place.

The heater of Figures 1 to 7 is constituted by a generally rectangular casing 20 having air inlet openings 22 adjacent its bottom and a pair of oppositely facing air outlet openings 24 in its side walls adjacent its top. Preferably the air outlet openings are covered by an ornamental grill or screen as indicated at 26 in Figures 1 and 2. A pair of angle brackets or the like 28 are preferably secured to opposite sides of the casing 20 just below the air outlet openings 24 and the top of the casing 20 is open, a removable lid or cover 30 preferably being provided to close it. An elongated burner 32 is centrally mounted in the lower part of the casing 20 and is supplied with fluid fuel, preferably gas, through a pipe 34 leading to a suitable source of supply.

The supply of fuel to the burner is controlled by an automatic valve indicated generally at 36 as will be explained more fully hereinafter.

A heat transfer unit is adapted to be inserted through the top of the casing 20 and comprises an open ended shell 38 having projecting arms 40 secured to the upper end thereof to rest on the brackets 28 and hold the shell in place in the casing. A series of fins 42 is secured to each side of the shell 38 and the fins support a combustion chamber 44 centrally of the shell. The combustion chamber has an open bottom to overlie the burner 32 and is formed with upwardly tapering side walls and a closed top, baffles 46 preferably being secured to the combustion chamber walls to facilitate the transfer of heat thereto. At one end the combustion chamber is formed with a flue connection 48 extending through a suitable opening in the casing for connection with a suitable flue or stove pipe 50, the connection 48 preferably being provided with a draft diverter opening 52 to reduce the stack effect on the combustion chamber.

It will be noted that the heat transfer unit is of such a size that it can be inserted through the open top of the casing 20, the arms 40 resting on the brackets 28 to hold it in place. The shell 38 Is smaller than the casing 20 whereby a space will be left therebetween which forms an auxiliary air passage. This arrangement prevents radiation of heat to the casing 20 and air circulating between the casing 20 and shell 38 will carry away a large part of such heat as does pass the shell 38 thereby keeping the outer casing 20 relatively cool.

Since the heat transfer unit and the casing are heated to different temperatures they tend to expand different amounts, the transfer unit expanding to a much greater extent than the casing. However, since the unit is supported at its upper end close to its connection to the flue, the expansion will have substantially no effect on the flue connection and it can be made tight. At the same time the unit is free to expand downwardly since the lower open end of the combustion chamber merely fits loosely around the burner. Therefore, repeated expansion and contraction will have no deleterious effect on the device and will not tend to loosen any of the connections.

When the burner 32 is burning, its products of combustion will rise in the combustion chamber 44 to heat the walls thereof and the fins 42 and eventually will pass out 'through the flue 50.

Heating of the combustion chamber walls and fins causes air to circulate by natural draft head, cold air from the room entering through the inlet openings 22, rising through the passages formed by the shell 38, the fins 42 and the casing 20 and passing out of the outlet openings 24 in heated condition.

It is preferable to have the heated air discharged in a more or less horizontal direction to diffuse it more evenly through the room and for this purpose a V-shaped baffle 54 is preferably 3a mounted in the casing 20 above the heat transfer unit. The baffle 54 may be inserted through the open top of the casing 20 or through the openings 24 but preferably rests on top of the heat transfer unit in such manner as to direct air substantially horizontally out both of the outlet openings 24.

Where it is desired to mount the heater adjacent a wall such as indicated at 56 in Figure 6, a baffle such as 58 may be used in place of the V-shaped baffle 54. The baffle 68 is a smooth continuous sheet resting at one end on the arms 40 or bracket 28 and at its other end adjacent the top of one of the outlet'openings 24.

Thus the baffle 58 directs all of the air rising in the casing through one outlet opening 24 and serves to close off the other outlet opening.

The burner 32 is preferably controlled automatically in response to the temperature of the room or other space to be heated and for this purpose any one of many automatic control systems may be provided. As best seen in Figure 7, one system comprises the valve 36 which is formed with two valve chambers 60 and 62, the supply pipe 34 communicating with the valve chamber 60 and a pipe 64 terminating in a valve seat in the chamber 62 and leading to the burner 32.

The end of the pipe 64 is adapted to be closed by a valve disc 66 carried by a flexible diaphragm 68, one side of which is exposed to fuel pressure in the chamber 62. Fuel pressure is communicated to the opposite side of the diaphragm 68 through a passage 10 opening into the chamber S62 and restricted by a threaded plug 12. The passage 70 communicates with the top of the diaphragm 68 and with a pipe 74 which leads to a valve 76.

The valve 76 is adapted to be mounted in any convenient place in the room to be heated and is controlled by a bimetal thermostat 78 having an adjustment 80. Fuel passing the valve 76 is conducted through a pipe 82 back to the valve 31 and from there through a pipe 84 to the burner 32.

Preferably the pipes 74 and 82 are concentric as shown to facilitate handling and installation but it will be apparent that two separate pipes could be used if desired. A disc valve 86 is mounted on a stem 88 in the chamber 60 and is adapted to seat adjacent one end of the chamber to prevent the passage of fuel from the pipe 34 to the chamber 62 when closed. The valve stem 88 is conpected at one end to a bellows 90 which is connected to a bulb 92, the bulb and bellows forming a fluid type thermostat. The bulb 92 is arranged above to be heated by a pilot burner 94 which is connected to the chamber 60 by a pipe 96 in such a manner that the pipe 96 will be closed by the valve disc 86 when it is moved to its closed position.

The opposite end of the stem 88 is connected to a spring disc 98 which is arranged to bias the valve 86 toward its closed position but which will g2 yield to pressure in the bellows 90 to permit the valve to open. The spring disc 98 is arranged to operate with a snap action so that the valve 86 is always fully open or fully closed and is connected to a stem 100 which carries a second valve 102 and which projects through the chamber 60 to provide a manually operable button. Preferably the end of stem 100 is covered by a cap 104 to prevent accidental opening of the valve 102.

The valve 102 controls a by-pass passage IQ6 formed in the wall of the chamber 60 and communicating with the pipe 96 posterior to the valve 86.

When the pilot burner is burning the bulb 92 is heated to create pressure in the bellows 90 urg- 85 ing the valve 86 to its-open position and snapping the disc 98 to the right as shown in Figure 7.

At this time fuel entering the chamber 60 through the pipe 34 will flow around the valve 86 into the chamber 62 where its pressure will act on the bottom of the diaphragm 68 to urge the valve 66 to its open position. At the same time fuel in the chamber 62 will flow through the passage 70 to exert pres-re on top of the diaphragm 68 to urge the valve to its closed position. If the room is below the temperature for which the thermostat 78 is set by the adjustment 80 the valve 76 will be opened, as shown, to vent fuel from the top.of the diaphragm through the pipes 74, 82 and 84 to the main burner 32. Thus the pressure on top of the diaphragm 68 will be reduced, it being noted that the pipes. 74, 82 and 84 are larger than the passage 70, and the valve 66 will open due to the influence of fuel pressure on the bottom of the diaphragm 68. At this time fuel will flow from the pipe 34 through the chambers 60 and 62 and the pipe 64 to the burner 32, being ignited by the pilot burner 94, as it flows from the main burner.

As the room temperature increases it will finally reach a point where the thermostat 78 will close the valve 76. Fuel will, however, continue to flow through the passage 70 until the pressure on both sides of the diaphragm 68 is equal, at which time the valve 66 will close under the influence of gravity to shut off the flow of fuel through the pipe 64 to the main burner.

If the pilot burner 94 should be extinguished the fluid in the bellows 90 and bulb 92 will contract, relieving the pressure on the stem 88 and permitting the spring disc 98 to close the valve 86. At this time all flow of gas will be shut off regardless of the position of the valve 76 and all danger of unburned gas escaping in the room is eliminated. To relight the pilot an operator should remove the cap 104 and depress the end of the stem 100 to open the valve 102. It will be noted that the very slight movement of the stem 100 is not sufficient to snap the disc 98 but that the disc will yield slightly to permit the valve 102 to open.

With the valve 102 open fuel will flow through the by-pass 106 and pipe 96 into the pilot burner and may be ignited by a match or the like held over the pilot burner. The operator should hold the valve 102 open until the bulb 92 is heated sufficiently to create a pressure in the bellows 90 which will snap the disc 98 and open the valve 86. The valve 86 will remain open as long as the pilot burner is burning and the system will operate under the control of the room thermostat 7& as explained above.

, Figures 8 to 12 show a modified embodiment of the invention and for the sake of brevity of description parts therein corresponding to like parts in Figures 1 to 7 have been designated by the same reference numbers plus 100. In this construction the burner 132, instead of being mounted in the casing 120, is secured to the combustion chamber 144 by means of T-shaped supports 145 which are secured to the sides of the combustion chamber and carry the burner.

Also the outlet opening 124 is made large enough to permit insertion of the heat transfer unit therethrough and the flue 150 extends straight upwardly from the center of the combustion chamber. As will be best seen in Figure 10 the baffle 158 is provided with a central opening through which the flue 150 passes so that air passing through the casing will flow around the flue and will be directed out substantially horizontally through the outlet opening 124.

Above the baffe 158 the casing 120 is provided with air inlet openings 123, (Figures 8 and 9) and a supplemental casing 125 is mounted above and forms a continuation of the casing 120. The casing 125 encloses the upper portion of the flue 150 and is formed with an air outlet opening 127. When the flue is hot, air will enter the openings 123 and circulate around the flue out the opening 127 to provide an additional heating effect and to cool the top of the casing 120 and the casing 125.

The unit of Figures 8 to 12 is generally mounted against a wall as indicated in Figure 8 and the flue 150 preferably extends through the wall to the outside or into a suitable stack or the like. While the back of the casing 125 is shown as being open, it may, if desired, be closed by a suitable plate or the like having an opening for the flue 160.

While two embodiments of the invention have been shown and described in detail, it will be apparent that many changes might be made therein and it is not intended to be limited to the forms shown nor otherwise than by the terms of the appended claims.

What is claimed is: 1. A heater comprising a casing having a removable top and formed with an air inlet opening adjacent its bottom and an air outlet opening adjacent its top, a burner mounted in and supported by the lower portion of said casing, a heat exchange unit adapted to be removably inserted through the top of the casing and including a passage for the hot combustion products from said burner having its bottom end open to receive said products and its upper end formed for connection with a flue, elongated supporting members secured to the sides of the casing, and projecting arms on the unit to engage said supporting members to support the unit in the casing.

2. A heater comprising a casing having an air inlet opening adjacent its bottom and an air outlet opening adjacent its top, a burner in and supported by the lower part of the casing, and a heat exchange unit in the casing above the burner, said unit comprising a substantially vertical rectangular conduit member closed at its top and forming a passage for hot products of combustion from the burner and having its bottom end open to receive said products and its upper end formed for connection with a flue, a plurality of heat conducting fins extending outwardly from opposite sides of the conduit member with the end ones of said fins lying flush with the ends of the member, and sheets secured over the edges of said fins and defining air passages therebetween said sheets being spaced from the casing to provide air passages therebetween. 3. A heater comprising a casing formed with an air inlet opening adjacent its bottom and an air outlet opening adjacent iLs top, a burner mounted in and supported by the lower portion of said casing, a heat exchange unit in said casing including a passage for the hot combustion products from said burner having its bottom end open to receive said products and its upper end formed for connection to a flue, elongated supporting members secured to the sides of the 5o casing adjacent the upper portion thereof and projecting arms on the upper portion of the unit engaging said supporting members to support the unit In the casing.

FRANCIS A. FURLONG.