US1463142A - Apparatus for controlling combustion - Google Patents

Description

H/flfA/TOR fiWMDM 3 Sheets-Sheet 1 July 24, 1923.

F. H. BROWN APPARATUS FOR CONTROLLING COMBUSTION Original Filed March 28, 1917 July 24, 1923. 1,463,142

F. H. BROWN APPARATUS FOR CONTROLLING COMBUSTION Original Filed March 28 1917 3 Sheets- Sheet 5 WA *1 Mt Patented July 24, 1923.

UNITED STATES PATENT OFFICE.

FRANCIS H. BROWN, 0F GLENOLDEN, PENNSYLVANIA, ASSIGNOR, BY MESNE ASSIGN- MENTS, TO THE HAGAN CORPORATIUN, OF PITTSBURGH, PENNSYLVANIA, A

CORPORATION OF PENNSYLVANIA.

APPARATUS FOR CONTRDLLING COMBUSTIGN.

Original application filed March 28, 1917, Serial No. 157,821. Divided and this application filed October so, 1920. Serial No. 420,619.

T 0 all whom it may concern.

Be it known that I, FRANCIS H. BROWN, residing at Glenolden, in the county of Philadelphia and State of Pennsylvania, a citizen ofthe United States, have invented or discovered certain new and useful Improvements in Apparatus for Controlling Combustion, of which improvements the following is a specification.

The invention described in this application is a division of an application Serial Number 157921, filed by me March 28, 1917, consisting of a combination of mechanisms for controlling combustion, a prominent feature of which is the automatic control of the fuel feed by means of mechanism regulated by and in accordance with variations of pressure in the furnace posterior to the bed of fuel.

The invention is designed to be utilized in conjunction with any desired type of fur nace and in conjunction with any desired type of fuel, as for example, solid, liquid, or gaseous fuel, so that the introduction of such fuel to the point of combustion will be accurately controlled in accordance with the varying conditions which are taking place in the furnace.

A further purpose of this invention is to utilize in conjunction with the automatic control of the fuel feed, mechanism as for example a stolrer or its equivalent means for automatically varying the furnace pressure in accordance with the variation in load on the furnace. This load varies in character in accordance with the character of the furnace employed and in a boiler furnace the load would be the variation in the demand for steam while in a heating furnace it might be the variation in heat within the furnace.

For the purpose of illustrating my invention I have shown in the accompanying drawings typical embodiments of it which are at present preferred by me since these embodiments will give in practice satisfactory and reliable results although it is to be understood thatthe various instrumentalities of which the. invention consists and by means of which my method can be carried out, can be variously arranged and organized and that my invention is not limited to a precise arrangement and organization of these instrumentalities as herein shown and descrlbed.

- Fig. 1 represents in sectional elevation one type of a furnace having combined therewith my improvements in controlling mechanisms; Fig. 2 represents in side elevation on an enlarged scale an automatic regulatmg device seen in Fig. 1; Fig. 3 shows in sectional elevation the controlling valve seen in Fig. 4.; Fig. 4 shows partly in section and partly in elevation the pressure regulator seen in Fig. 1; Fig. 5 shows in side elevation another embodiment of my invention illustrating a different type of fuel feeding mechanism for feeding liquidor gaseous fuel; 6 shows a section on line VIVI, Fig. 2; and Fig. 7 is a view similar to Fig. 1 illustrating another embodiment of my invention.

It is to be understood in carrying out my novel method in practice that I do not desire to be limited to any special type of stoker or fuel feeding mechanism, to any special type of regulator controlled by the variation in load on the furnace, to any special type of a regulator controlled by varying conditions posterior to the point of combustion, such as for example, a pressure regulator, or to the steps of utilizing natural or mechanical draft or any special type of mechanism for controlling forced draft.

1 designates a furnace of any desired or conventional type, and is illustrated in the drawings, it is indicative of one of the individual furnaces of a battery of boilers for the generation of steam so that the load on each furnace is the variation in steam demand. 2 designates the ash pit and 3 the fuel feeding mechanism which is intended to disclose the equivalent of a stoker, and consists of a travelling grate, the movement of which is controlled by an engine 4 of any desired or conventional type and which is illustrated diagrammatically in Figure 1. It will be understood that the engine 4 is operatively connected with the travelling grate 3 in order to impart movement thereto.

5 designates a combustion chamber which is in communication with the individual stack 6, through which the products of combustion pass tothe main furnace stack 7. 8 designates a boiler, in which the steam is ficient clearness to enable one to comprehend the operation thereof.

11 designates a conduit which is in communication with the combustion chamber 5 and has its free end extending above the liquid in a container 1 and into the chamber 13 of an inverted tank 14. This tank 1 1 is located within the outer inverted tank 13 and these tanks have their lower ends sealed by the liquid in the container 12. The inverted tanks 141 and 15 are carried at one end of a lever 16 fulcru ed in any desired manner and provided with an adjustable counterbalance 17.

18 designates a link which is connected witha valve 19 which controls admission and discharge of motive fluid through the pipes 20 and .21 to opposi. e ends of a motor chamber-22, and in which is located a rec1procatory piston 23. 24 designates a piston red the lower end of which connected provided with an inlet 31 and an outlet 32.

The inlet communicates by means of a port 33 with the interior of the valve casing 30 and the port 29 registers at times with the port 33. The valve 28 is shown as a cup-shaped valve having the ports 34 through one end to balance the pressure of motive fluid against the valve. The inlet 31 communicates by means of a valve-con trolled conduit with the steam dome 9.

The outlet 32 communicates by .neans of a valve controlled conduit 36 with the engine 4. The piston rod 2 1 of the pressure regulator 10'has connected to its upper end a cable 37 which passes over pulleys 3S and is connected to a damper 39 in the auxiliary draft conduit 10 which communicates with the ash-pit 2. The damper 39 is provided with an adjustable counterbalance 11. The auxiliary draft conduit 10 communicates with the main draft conduit 12 which is in communication with each furnace of the battery. The furnace may be operated under either a natural or forced draft and T have illustrated in Figure 1 a draft conduit 13 for the natural draft so that when the damper 141 is closed, the furnaces will operate under natural draft. When the damper 1a is open, as indicated in dotted lines in Figure 1, the blower a5 is in communication with the maindraft conduit 42 so that the furnaces will operate under forced draft. ihe blower 4-5 is intended to illustrate the conventional type of forced draft wherein the blower is actuated by an engine 16 which is provided with a governor 17, so that the speed of the engine can be automatically controlled.

Each individual stack 6 is provided with a damper 18 having a counterbalance 49 and provided with a cable 50 which extends into a position accessible to the engineer in order to provide for the manual control of the oamper 18. Each individual stack 6 is pro vided with an automatically controlled damper 51 which is provided with a pulley 52 around which passes a cable 53, which is provided with a counterbalance 5 1, said counterbalance being adjustable. The cable 53 is connected to a piston rod 55 of a motor 56. The admission and exhaust of motive fluid to the motor 56 is controlled by means of a pilot valve 57 and the stem of the valve, as indicated by 58, is connected to a lever 59 to which pivoted an adjustable connection (30, the other end of which is connected with a lever 61. The lever 61 is provided with an adjustable counterweight 62 and an adjustable counterbalance The lcver is actuated by a diaphragm vmotor (3st of any conventional type, one side of which is subjected to variations in steam pressure which is introduced into proximity to said diaphragm through a steam conduit 65 which is in communication with the steam dome 9. The lever 59 is connected by means of a link 66 with an elbow lever 67 which is fulcrumed to a fixed point. This elbow lever 67 carries at one end shoe 63 which is slidably mounted upon a guide 69 pivoted at its lower end to a fixed point as 70 on a bracket 71 which is adjustably fixed to the piston rod 55 which is connected to the cable 53. The upper end of the bracket 71 is provided with a worm72 adapted to be manually adjusted and which meshes with a rack 73 at the upper end of the guide 69 in order to provide for the angular adjustment of said guide 69. This bracket '71 and its adjuncts form a compensating mechanism, so that a graduated adjustment of the damper 51 is automatically provided in accordance with variations in the steam pressure.

It will be seen from Figure 6 that the shoe 58 is pivotally carried by the bifurcated end of the lever 67.

In Figure 1, I have illustrated the mechanism for providing an automatic control of the fuel feeding mechanism which can be employed in case a solid fuel is used, and

in Figure 5. I have illustrated a typical mechanism which can be employed in case a liquid or gaseous fuel is used. The cable 37 in Figure 5 would be connected to the pressure regulator 10 and controls the auxiliary draft conduit 40 to the individual furnace in the same manner as already described with reference to Figure 1, and I have therefore indentified thecorresponding parts by the same'reference characters. Connectedto the cable 37 is a cable 74 which passes around a controlling valve 75 and is provided with acounterbalance 76. The valve 75 automatically controls the passage of fuel of a liquid or gaseous nature through the nozzle or injector 77. The other parts of the mechanism for controlling combustion would correspond to the typical'mechanism illustrated in Fig. 1.

The operation of my novel apparatus will now be readily apparent to those skilled in the art to which this invention appertains and is as follows motor 56 to cause the damper 51 to move in the direction of opening and thereby increase the pressure posterior to the point of combustion, such as for example, the furnace pressure in the combustion chamber, since such combustion chamber is now in communication with the atmosphere through the stack 6 of the individual furnace. This change in pressure causes the lever 16 to be actuated to operate the pilot valve 19 and admit motive fluid to the motor 22 and thereby actuate the piston rod 24:. The piston rod 24 will move downwardly thereby causing the lever 25 to move thevalve stem 27 upwardly, and steam is permitted to pass from the conduit 35 through the inlet 31, the ports 33 and 29, through the port 32 into the conduit 36 and thence to the engine 4 to cause the fuel to be fed into thefurnace. This downward movement of the piston rod 24 actuates the cable 37 to open the valve 39 and permit the draft for combustion to pass from the maindraft conduit 42 into the ash-pit 2 of the individual boiler.

In order to illustrate one manner of carrying out my method, I have preferred to show a single instrumentality for simultaneously controlling the operation of the fuel feeding mechanism and the introductionof draft for combustion, but it is to be understood that it is within the scope of my invention to employ separate mechanisms for such control in accordance with conditions and requirements met with in practice.

When the load on the furnace decreases, such as for example, a decrease in the demand for steam, the motor 56 will be actuated to cause the damper 51 to close to a degree corresponding to the change in steam pressure, and the fuel feeding mechanism and the primary draft will be correspondingly actuated to decrease the'amount of fuel being fed and the amount of air introduced for combustion. Owing to the provision of the compensating mechanism which is best illustrated in Figures 2 and 6, the damper 51 is not moved to a fully open or closed position on the variation in steam pressure but a graduated movement is provided. Thebracket 71, carried by thGPlS- ton rod 55 as it moves in one direction or the other, actuates the shoe 68 to move the valve stem 58 and correspondingly control. thepilot valve 57. It is not-essential in all cases arising in practice to use all of the steps of my method as herein set forth and they can be used alone and independently of each other or in any combination.

In so far as I am aware, I am the first in the art to devise the step of automatically controlling the fuel feed by Variations in furnace conditions posterior to the point of combustion, such as for example, the variations in the furnace pressure. I am also the first 1n the art, in so far as I am aware, to

employ in conjunction with such tep, the

automatic control of the primary draft in accordance with varying conditions posterior to the point of combustion, either alone or in conjunction with the step of automatically varying conditions posterior to the point of combustion in accordance with variations in load on the furnace or furnaces. It is therefore to be understood that my claims to such features are to be interpreted with the scope to which a generic invention is entitled. i

In some cases arising in practice, the damper 51 and its adjuncts may be dis pensed with and the damper 48 can be manually controlled to vary the conditions of pressure posterior to the point of combustion.

Another embodiment of my invention is seen in Figure 7, wherein instead of controlling the damper 51 by variations in steam pressure, it is controlled by variations in furnace conditions posterior to the point of combustion, such as for example, the furnace pressure. In this embodiment, the steam regulator seen in Figure 2 is dispensed with, and the cable 37 is connected to or forms a part of the cable 53 which controls the stack damper and also actuate the controlling means for controlling the introduction of fuel- It is to be understood that in conjunction with this embodiment seen in F ure 7, I dispense with the damper 39 and its automatic control, and the engine is automatically controlled by steam passing from the dome 9 through the conduits 78, the bypass 79and the steam regulating valve 80, the valve 81 being closed and the valves 82 opened and the governor being disconnected. in the method first described in connection with Figure 1 the valve 82 would be closed and the valve 81 would be open. In accordance with my present invention, one is enabled to maintain a constant rate of combustion in each furnace, irrespective of the thickness of the bed of fuel or the resistance olfered to the draft.

It will be apparent that I have devised a new and useful method of controlling combustion, v-shich embodies the features of vantage enumerated as desirable in the state ment of the invenuionandthe above descrip tion, and while I have, in the present instance, shown and described typical embodiments thereof which will give in practice satisfactory and reliable results, it is to be understood that these embodiments are susceptible of modification in various particulars Without departing from the spirit or scope of the invention or sacrificing any of its advantages.

it is characteristic of the invention herein described that the pressure of gases in the furnace is automatically variable by and in accordance with the static pressure of steam or vapor in the boiler and that the rate of operation of the motor for the fuel feeding mechanism is variable by and in accordance with changes of pressure of the gases as de termined by the static pressure of vapor in the boiler.

l. claim herein as my invention:

1, in an apparatus for controlling combustion, the combination of a furnace, means for feeding fuel into the furnace and means for regulating the feed of fuel by and in accordance with variations in furnace pres sure.

2. In an apparatus for controlling combustion, the combination of a furnace, means for fe ling fuel to the furnace, means for supplying air for combustion and means for regulating the feed of fuel and the supply of air by and in accordance with variations furnace pressure.

3. In an apparatus for controlling combustion, the combination of a furnace, means for feeding fuel. to the furnace, means for supplying air for combustion to the furnace and means operative by and in accordance with variations in furnace pressure for simultaneously controlling the feed of fuel and the supply of air.

4. In an apparatus for controlling combustion, the combination of a furnace, means for regulating the pressure of gases in the furnace, means for feeding fuel to the furnace and means operative by and in accord ance with the pressure of the furnace for controlling the feed of fuel.

5 In an apparatus for controlling combustion, the combination of a furnace, means for regulating pressure of'gases in the furnace, means for feeding fuel to the furnace, means for feeding air for combustion to the furnace and means for controlling the feed of fuel and the supply of air by and in accordance with variations in furnace PIGC'QUFG.

(3. .n r apparatus for controlling com bustion the combination of a boiler having 7 O furnace, means for varying the pressure of the gases in the furnace by and in accordance with changes in the static pressure of vapor generated, means for feeding fuel to the furnace and means for varying the rate o feel of fuel by and in accordance with vaimaons in furnace pressure.

In an apparatus for controlling cou bust-ion, the combination of a boiler having a furnace, means operative by and in accord auce with clizuiges of pressure of vapor generated for controlling the discharge of gases from the furnace, means for feeding fuel-to the furnace, means for supplying air for comluistion to the fur race and means operative by and in secure tnce with changes of pres sure in the furnace for regulating the feed of fuel and the supply of air.

8. In a furnace structure, the eombinatio'i of furnace chamber, mechanism for feeding fuel automatically, mechanism includins; a movable element subjected in opposite directions to furnace pressure and to atmospheric pressure for changing the rate of operation of the fuel feeding-mechanism.

9. In a furnace structure the combination of the furnace chamber, a mechanical fuel feeding mechanism and a speed changing device applied to said fuel feed, of an automatic control of said speed changing device including a movable element subjected in opposite directions to furnace chamber pres sure and to atmospheric pressure.

10. In a furnace structure the combination with a furnace chamber, a mechanical fuel feed, and a speed changing device applied to said fuel feed, of an automatic con changing device including a movable element maintained in equilibrium between atmospheric pressure and the sum of two forces; one, furnace-chamber pressure, and the other, a force constant while said draft passageways remain constant, substantially as described.

12. In a furnace structure the combination with a furnace chamber, a mechanical fuel feed, and a speed changing device ap plied to said fuel feed, of an automatic control for said speed changin device including a movable element maintained in equilibrium between atmospheric pressure and the sum of two forces: one, furnace-chamber pressure, and the other gravity, substantially as described.

13. In a furnace structure the combination with a furnace chamber and a mechanical fuel feed, of a counter-weighted fluidsealed bell communicating with said furnace chamber, a speed changing device" applied to said fuel feed, and means operated by said bell for controlling said speed-changing device, substantially as described.

14. In a furnace structure the combination with a furnace chamber and a me chanical fuel feed, of a liquid-sealed bell, an adjustable counterweight for said bell, pneumatic connection from said furnace chamber to said bell, a speed-changing de vice applied to said fuel feed, and means operated by said bell for controlling said 15. In an apparatus for controlling combustion, the combination of a boiler having a furnace, a damper regulating the discharge of gases from the furnace, means controlled by the pressure of steam for operating the damper, means for feeding fuel to the furnace and means operative by and in accordance with the pressure in the furnace for controlling the feed of fuel.

16. In an apparatus for controlling combustion the combination of a boiler having a furnace, a damper for regulating the flow of gases from the furnace, means for feed ing fuel to the furnace, means for feeding air for combustion to the furnace, means operative by and in accordance with changes of pressure of steam for regulating the stack damper, and means for controlling the feed of fuel and the supply of air by and in accordance with variations in furnace pressure.

17. In an apparatus for controlling combustion, the combination of a boiler having a furnace, a stack damper for controlling the flow of gases from the furnace, means operative by and in accordance with the static pressure of vapor generated for controlling the stack damper, a stoker for feeding fuel to the furnace and means regulating the operation of the stoker by and in accordance with furnace pressure.

In testimony whereof, I have hereunto set my hand.

FRANCIS H. BROWN.

Images