US1319654A

US1319654A - Air heating furnace

Info

Publication number: US1319654A
Authority: US
Publication date: 1919-10-21
Anticipated expiration: 1936-10-21

Description

L. LEE.

AIR HEATING FURNACE.

APPLLcATloNjFILED MAY22.1918.

Patented Oct. 21,1919.

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L. LEE.

A111 HEATING FUHNACE.

APPLICATION HLED MAY22,19ia.

1 3 1 9, 65 4: Patented Oct. 21, 1919.

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uUNITED STATES PATENT' OFFICE;

LEIF LEE, 0F YOUNGSTOWN, OHIO, ASSIGNOR TO THE YOUNGSTOWN SHEET & TUBE COMPANY, OF YOUNGSTOWN, OHIO, A CORPORATION OF OHIO.

AIR-HEATING FURNACE.

Application led May 22, 1918.

T 0 all whom t may concern:

Be it known that I, Lnrr Lun, a citizen of the United States, residing at Youngstown, in the county of Mahoning and State of Ohio, have invented a new and useful Improvement in Air-Heating Furnaces, of

which the following is a full, clear, and eX- act description, reference being had to the accompanying drawings, forming part of this specification, in which- Figure 1 is a sectional plan view of a furnace embodying my invention the section being taken on the line I-I of lig. 2.

Fig. 2 is a transverse section taken on the line-IIH-II of Fig. 1.

Fig. 3 is a partial longitudinal section taken on the line III-III of Fig. 1, and

Fig. 4 is a detail sectional view.

My invention has relation to air heating furnaces; and is designed to provide a 'furnace in which air may be rapidly heated in large volume. Also to provide a furnace of this character having a novel arrangement of the air heating elements and possessing other advantages, some of which are hereinafter pointed out.

In the accompanying drawings I have illustrated my invention as applied to a thaw house for thawing out frozen cars of material, but I desire it understood that my invention is not limited to this purpose, but that it may be applied for heating air for any desired purpose.

In these drawings, the numeral 2 designates the walls of the furnace and thaw house, of any usual or suitable construction; and 3 designates the walls of one of my improved air-heating furnaces with which the thaw house is equipped.

This furnace is provided with an inclosed heating chamber 4 having therein a plurality of air heating and conducting pipes 5 which are of inverted U-form, the pipes being placed in bank in this chamber with suiiicient opening or spaces between them to admit of the relatively free circulation of a gaseous heating medium. These pipes are secured at their lower ends in suitable header plates 6, which can be made in sections and readily removed. Preferably each pipe has its ends separately removably seated in these header plates, as indicated at 7 in Fig. 4, whereby any defective pipe may be readily removed and replaced. The roof of Specification of Letters Patent.

Patented Oct. 21, 1919.

serial No. 235,943.

the heating chamber 4 may be conveniently 'formed of a series of spaced I-beams 8, the spaces between which are filled with curved sheets 8, acting as arches, and covered with sand, as indicated at 8b (Fig. 8) and which can be readily removed to permit the removal of said arches. Any other suitable construction may, however, be employed which is of a character to permit of ready access to the heating chamber and pipes.

The heating pipes 5 are arranged in the heating chamber at the sides of and above a central flue'Q, which forms an air supply chamber, which at the rear end of the furnace opens downwardly into an equalizing chamber 10 extending the full length of and below the heating chamber, centrally thereof. The inlet ends of the pipes 5 communicate with this equalizing chamber and receive the air to be heated directly therefrom. Air is supplied to the :due 9 from any suitable source such as the fan or blower 11. The opposite ends of the pipes 5 open downwardly into a hot air chamber 12 which, in turn, is shown as opening into a lower hot air duct 13, from which the hot air is taken off for use at the desired point or points.

The heating medium may consist of combustion or waste gases from industrial furnaces, such as open hearth furnaces, heating furnaces, glass furnaces, boiler furnaces, etc., such gases being suitably conducted into one side of the heating chamber 4. In the embodiment of my invention which I have illustrated, I have shown the furnace as having three combustion chambers 14 arranged at one side of the heating chamber, and communicating therewith by means of the openings 15 which enter the base of the heating chamber through one of, the side walls. These combustion chambers may be fuel fired, but are shown as provided with grates 16, or they may be fired by gas or oil, as indicated at 17. Each of the combustion chambers is provided with a plurality of cold air inlet openings 18 which can be controlled by hand by means of damper bricks or other suitable means so as to regulate the amount of cold air which will enter. The products of combustionrmiXed with this cold air pass to the openings 15 through checker-work 19, which thoroughly mix the gases and air before they reach the pipes. In this way the temperature of the combustion Agases is reduced to such an extent that the pipes will not be injured. These pipes are preferably of steel.

20 designates a baffle wall placed at that side of the air supply flue 9 which is nearest the openings 15 and which is arched over the top of said flue, this baille acting to cause a proper circulation of the combustion gases around the hot pipes. The waste gases leave the heating' chamber at the opposite lower side portion through openings 21. These openings are provided with individual outlet connections 22 communicating with. the 'common flue 23 and each connection 22 is preferably provided with a separate regulating damper or valve 24. The waste flue 28 may, as shown, be connected with the inlet of a suction fan 25 whose exhaust is connected` with a short stack 26; or the llue 23 may be led directly to a draft stack.

This suction or exhaust fan 25 is preferably connected either indirectly, or directly, as shown, with the blower 11, so that when the blower is stopped the exhaust fan will stop simultaneously, thus shutting off the draft the moment the air sup-ply stops. In this manner burning out of the heating pipes is prevented. I may also provide any suitable regulating device of well known character, which, where gas is used for fuel, will shut off the supply of gas; or which, in the case of solid fuel, will regulate the air supply to the grates. Regulators of this character, such as thermostatic regulators with the thermostatic element located in the heating chamber near the openings 15, may be used for this purpose. Or regulators controlled by the pressure of the discharged air may also be employed.

To further protect the pipes 5 adjacent to the openings 15 so that they will not be subjected to too high a teniperature of the contacting gases, they may be surrounded at this end portion by suitable protecting sleeves 27.

The llue 9 leading from the blower is provided with a suitable damper 28; and the exhaust flue 2S is also shown as provided with a damper 29.

In the application of my invention which I have shown and in which the air is heated for the purpose of supplying` hot air to a car thawing chamber, the heating furnaces, or as many of them as may be necessary, are arranged above the thaw room 30. The hot air is taken from the hot air duct 13 and supplied to this thaw room 30 through any suitable system of pipes 31. The ceiling 32 of the thaw chamber is shown as perforated, so that the hot air, after passing through said chamber, will rise into the air space below the furnace, and pass through suitable openings 33 in the framing back to the ducts 34 and into the eyes of the fan 11. Ther dampers 35 control the passage of air from these return ducts into the fan. In this manner the warm air after passing through the thaw room can be returned to the fan for re-use.

The provision of the air equalizing chamber 10 causes air to enter all the heating pipes at substantially equal pressure. By

' )assino' the air through these relativel f' small pipes it gets thoroughly heated, as each particle or molecule of air comes into more or less contact with the heating surfaces. The arrangement of the openings by which the heating medium enters and leaves the heating chamber is such as will, in connection with the baille 20, cause the maximum amount of the heating surfaces of the pipes to be exposed to the heating action of the gases. The provision of the separate outlet connections leading to the stack flue, each connection having its own damper, enables an even draft to be obtained throughout the whole length of the heater.

It will be noted that the heating pipes are held at their ends only, and owing to their U-shape are free to individually expand and contract without injury thereto.

38 indicates a cleaning out line into which ash, etc., may fall from the checker-work 19 and from which such ash can readily be removed by means of suitable doors 39.

As herein indicated the particular embodiment of my invention which I have shown and described, is illustrative only and I do not desire to be limited thereto. Obviously the particular construction will depend largely upon the purposes for which the air is to be heated and the particular character of the heating` medium which is employed.

I claim:

1. Air heating apparatus, comprising a heatingchamber having` therein a plurality of inverted U-shaped air heating pipes, said pipes being arranged in concentric series or banks extending` longitudinally in the chamber, a combustion chamber arranged at one side of the heating chamber, and a mixing chamber intermediate the combustion chamber and the heating chamber and communicating with both of said chambers, said mixing chamber having meanstherein for causing the products of combustion from the heating chamber to be mixed with relatively cold air before they are delivered to the heating chamber, ysubstantially as described.

2. Air -heating apparatus comprising a heating chamber having inverted U-shaped heating pipes arranged therein in bank, means for causing a circulation of the air to be heated through said pipes, a combustion chamber having1 cold air inlet openings and communicating` with the heating chamber, and means for mixing thecold air and products of combustion as they pass from the combustion chamber into the heating chamber; substantially as described.

3. Air-heating apparatus comprising a heating chamber having inverted U-shaped heating pipes arranged therein in bank, means for causing a circulation of the air to be heated through said pipes, a combustion chamber having cold air inlet openings and communicating with the heating chamber, and means for mixing the cold air and products of combustion as they pass from the combustion chamber into the heating chamber, said means comprising checkerwork; substantially as described.

4. Air-heating apparatus comprising a heating chamber, a plurality of U-shaped air heating pipes arranged therein in bank, au air supply passage extending centrally of the bank of pipes, an equalizing chamber connected to said flue and with which said pipes communicate at one end, and a hot air duct into which said pipes discharge at their opposite end; substantially as described.

5. Air-heating apparatus comprising a heating chamber having a bank of heating pipes therein, means for causing a circulation oi the air to be heated through said pipes, means for introducing a heating medium into said chamber atone side thereof adjacent to the lower ends of said pipes, a plurality of separate waste gas outlets at the opposite side of said chamber adjacent to the opposite lower ends of said pipes', a draft flue with which said outlets are connected, and damper means in said flue and also in said outlet connection; substantially as described.

6. Air-heating apparatus comprising a heating chamber having a bank of inverted U-shaped heating pipes therein, means for causing a circulation of the air to be heated through said ipes, means` for introducing a heating medium into Jehe hea'tin chamber, said heating chamber having a p urality of outlet connections for the heating medium, Valve means for separately controlling said connections, a common iue into which said connections lead, and an exhaust fan connected to said flue; substantially as described.

7. Air-heating apparatus comprising a heating chamber having a plurality ol U- shaped air heating pipes arranged in bank therein, a blower for forcing the air through said pipes, means for circulating a heating medium in the heating,chamber around said pipes, an exhaust fan connected to the Waste gas outlets of said heating chamber, and a driving connection between the blower and the exhaust fan; substantially as described.

8. Air-heating apparatus, comprising a heating chamber having therein a plurality of heating pipes arranged in bank, a fan for causing a circulation of the air to be heated` through said pipes, a combustion chamber for supplying a heating medium to the heating chamber, and a fan arranged to eii'ect a circulation of the heating medium through said chamber, the two fans having a common driving connection, substantially as described.

9. Air-heating apparatus, comprising a heating chamber having a plurality of inverted U -shaped heating pipes arranged therein in bank, means for causing a circulation of the air to be heated through said pipes, a combustion chamber, and a mixing chamber' intermediate the combustion chamber and the heating chamber and through which the products of combustion pass on their way to the heating chamber, said mixing chamber having means for mixing relatively cold air with the products of combustion and thereby reduce their temperature and increase their volinne, substantially as described.

Inv testimony whereof, I have hereunto set my hand.

LEIF LEE.

Copies of this patent may be obtained for ve cents each, by addressing the Commissioner of Patents, Washington, D. C.