US1844042A - Coal burner - Google Patents

Description

Feb. 9, E932., c. 5, PARKER ET ALL.

COAL BURNER Filed Jan. 17, 192'5 Feb 99 51932, c. J. PARKER ET AL.

COAL BURNER Filed Jan. 17, 1925- 5 Sheeis-Shee 2 Fdo., @9 i932., c. J. PARKER ET M.,

COAL BURNER Filed Jan. 17 1925 5 Sheets-Shea?. 5

coAL BURNER c. J. PARKER ET AL 'Filed Jan.. l'T. 1925 Fdo. 9, 1932..

Feb. 9 E932.. c. J, PARKER @T AL mmm@ COAL BURNER 5 Sheets-Sheet 5 Filed Jan. 17 1925 [/v Vas/70H5 Patented Peas, 1932 UNITED .STATES I'Prarr-:N'l or-'rlca CYRUS J'. PARKER, CLARENCE '.l'. BURG, AND ARTHUR O. DADY, 0F PORTLAND, ORLEGOIEI';v

SAID BURGl AND SAID DADY ASSIGNORS T0 SAUF-PARKER; MARY 'E PARKER EXECUTRIIX OF SAID CYRUS J'. PARKER, DECEASED con. BURNER.

Application med January 17, 1925. Serialfllb. 8,059.

ated worm capable of being intermlttently operated.

The second object is to provide a means for varying the feed of said worm.

The third object is to so arrange the mechanism that the driving motor shaft operates directly on the operating mechanism and fan.

The fourth object is to provide a special construction in which a crank which operates a connecting rod is so arranged that the amount of movement transmitted by the rod canbe readily varied by providing a pawl and ratchet mechanism in which the pawl can be made to pick up any desired number of teeth on the ratchet.

The fifth object is to prevent the unconsumed gases which are being generated from backing up through the fuel which is being fed into the furnace.

The sixth object is to avoid the use of a long narrow retort such as is in common use with similar devices, and to provide a relatively short and broad retort wherein an ample supply of air is provided for the entire area of the retort.

A seventh object is to provide a special form of bridging tuyres which pass over the center of the feed worm and cause the oncoming fuel to be broken up and supplied with ample quantities of air, thereby greatly reducing the amount of clinkers which can be formed and of course improving the quality of the combustion.

The eighth object is to provide a special form of brick structure for conducting air under pressure to the tuyres.

The ninth object is the provision of an auxiliary set of tuyres completely surrounding the central set of tuyres, and means for controlling the supply of air delivered to the auxiliary tuyres independently from the air delivered to the central tuyres.

In Aactual use the device which is now being described is used in conjunction with a pressure-actuating thermostat, together with a relay switch which controlsthe operating motor for the purposeof automatically controlling the amount ofcoal fed into the device, but as the employment of such devices for the purpose of controlling feeding mechanisms of various kinds is well understood by those familiar with the art, their illustration i has been omitted since the do not of themselves constitute the novel eature of this dev1ce.

These and other objects will become more apparent from the specification following as illustrated in the accompanying drawings, in which:

Figure 1 is a side elevation of the device on a reduced scale. Figure 2 is a front elevation. Figure 3 is a plan showing that portion of the device which is inside of the furnace. Figure 4 is a longitudinal section taken along the line 4-4 in Figure 3. Figure 5 is a transverse section taken along the line 5-5 lin Figure 3. Figure 6 is a vertical longitudinal section through the worm feed mechanism. Figure 7 is a vertical section taken along the line 7 -7 in Figure 6.

- Similar numbers of reference refer to the same parts throughout the several views.

Referring in detail to the drawings, the device itself includes a worm housing 10 to one end of which is secured the hopper base 11 on whose upper side is attached a hopper 12 in which the fuel is placed. The opposite end of the housing .10 has an outwardly curved ioor 13 and an outwardly flanged rim 14. Inside of the housing 10 is placed a worm 15 on the Worm shaft 16 adapted to feed fuel through the housing 10 upwardly over the lioor 13 to the fire bed.

Attached yto the hopper base 11 is a housing 17 for the operating mechanism having a front 18 whose upper portion is hollow and is provided with a cover 19. In the lower portion of the housing 17 is journaled a worm drive shaft 20 on which is keyed a ratchet wheel 21 on Whose hub ends 22 are mounted the side plates 23 and 24.

The plates 23 and 24 support a spacer 25 on the in 26 and carry the pawl 27 which isy ends are attached the angle irons 80 which moun on'the pin 28 which passes through the arms 29 on the lates 23 and 24. The iposition of the pawl 2g is determined by a ro ler 30 which is attached thereto by means of a pin 31. The roller 30-is arranged to ride on the curved face 32 of :the feed stroke controlling arm 33 which has a downwardl extending arm '34 into which is scre e the 1 shank 35 formed` on the hexagonal head 36. The shank 35 passes through a curved slot 35-,A in the member 18.

Attached between the plates 23 and 24 is also a connecting rod 37 whose lower end 38 15 carries a pin 39 and whose upper end 40 is attached to the crank pin 41 on the crank shaft`42 which journals in the bearings 43 and 44. J amb nuts 45 on the connecting rod 37 hold the rod 37v against turning in its ends 2 38 and 40. A washer 46 is placed on the threaded end of the pin 41, which is also provided with a nut 47. A washer 46--A and a nut 47-A are placed on the end of the shaft 42. 35 The shaft 20 is provided with' friction washers 48 against which bears the thrust coupling 49 which is mounted on the threaded end 50 of the shaft 16 and is attached to the shaft 20 by means of the pin 51. The cover plate 52 extends around the shaft 16 and is attached to the hopper base 11 by means of the bolts 53.

On the shaft 42 .is keyed a worm wheel 54 which meshes with a worm 55 formed on the main shaft 56 whose shouldered ends 57 and 58 journal in the bearings 59 and 60 which are protected by the packed collars 61 and 62.- On the projecting end; 58 of the shaft 56 is mounted the rotor 63 of a fan 64 4 whose casing 65 terminates in an air duct 66 which passes through the front wall 67 of the furnace, as does also the worm housing 10.

A pipe 68 leads from the fan casing 65 at the point of the highest velocity of the air being delivered through the top of the housing 10 into the passing fuel, for reasons which will be explained later.

Mounted on the side of the members 17 and 18 is a base 69 which is supported at one 50 end by the legs 70 and on which is mounted a motor 71 whose shaft 72 is joined by the coupling 73 to the shaft 56.

It is desirable to provide a convenient means for regulating the amount of air which can be delivered by the fan and this is accomplished by means of the damper 74.

Turning now to that portion of the device which lies within the furnace itself there is constructed, in a somewhat rectangular form, a bricked structure consisting of end walls 75 and side walls 76 between which is formed the main air conducting chamber 77, in which is placed the sloping end of the worm housing `10. On the sides 78 of the housing 10 05 are secured the brackets 79 to whose outer rest on the brickwork 81 and support the worm housing 10 thereon. Between the front and rear sides of the rim 14 is placed the V-shaped trough 82, preferably in a manner'topermit of easy replacement and to allow air to enter the trough 82 from the chamber 77 either from the front, or rear, or both.

The upper sides of the angle irons 8O are level with the upper edges of the rim 14, and it is across these two elements that are placed the tuyres 83 having the inwardly pointing openings 84 and the outwardly pointing openings 85. A central row of tuyres 86 is identical with the outer row of tuyres 83, except that the members 86 are the same on both sides and` are adapted to fit upon the V-shaped trough' 82. The tuyres 83 and 86 are provided with the central walls 87 and 88 and the openings 84 and 89. The tuyres 83 themselves are not fastened down but merely fit into place between and on the rim 14 and the angle irons 80. y

In the walls 75 and 76 is formed an auxiliary air passage 90 over which are placed the auxiliary tuyres 91 between the fire brick 92 and 93, the latter of which rest upon the' flanges 94 on the outer side of the tuyres 83. In each of the walls 76 is formed a passageway 95 which is provided with a sliding door 96 adapted-to control the amount ofl air which can pass through the passageway 95 to the auxiliary air passage 90 and ultimately escape through the tuyres 91 into the combustion chamber.-

An opening 66-A extends through the wall 75 and connects the duct 66 with the chamber 77. It is preferable not to extend the passageway 90 across the opening 66-A: or the member 10 but to place a piece of sheet metal 97 supported by the bars 98 across the opening 66--A to support the fire brick 92 and 93 at this point. Air is supplied to the tuyres 91 over the member 97 from the passageway 90 at each end 99 and 100 of the passage 90r That portion of the housing 10 which includes the sloping bottom and the rim 14 forms a lire pot over which the combustion takes place.

The operation of the device is as follows: A supply of fuel is placed in the hopper 12 and the motor 71 started causing a supply of fuel and air to be delivered to the combus-A tion chamber. It is preferable, of course, to start the combustion with. the aid of light trashy material, and the supply of air appropriately regulated until the heavier fuelsy are ignited. .L

By loosening the member 36 and moving it laterally to the right the length of time which the curved surface 32 supports the roller 30 will be increased. In other words, the amount of travel of the pawl 27 during los CSI

its engagement with the teeth of the ratchet wheel 21 is decreased, and therefore rotation of the worm 15- is decreased, which means that the amount of fuel which is delivered to the combustion will also be decreased. Movement of the member 36 in the opposite direction will producean opposite result and increase the amount of fuel delivered to the combustion chamber during a given interval of time, assuming, of course, that the speed of the motor is constant.

As the fuel approaches the heat it is evident that the more volatile gases will be driven olf, and that unless other means are provided to prevent it, the pressure in the combustion chamber, which is naturally greater than the atmospheric pressure, will cause these gases to back up through the fuel in the housing and hopper and escape into the atmosphere of the furnace room, which, of course, would be very undesirable.

This condition, which is common in devices of this character, hasbeen overcome by utilizing aportion of the air from the fan 64 by simply tapping the casing 65 at the point where the air attains its highest velocity and by carrying a supply of air into the worm housing 10. as above described. It is evident that the air in the pipe 68 hasa much higher velocity and pressure than does the air in the chamber 77, and that any gas which is driven off from the solid fuel by the heat being generated will be carried on ahead ofthe solid fuel into the combustion chamber where it will be completely consumed.

One of the great diiiiculties experienced with this type of device is the formation of clinkers after the fuel has passed beyond reach of the agitating action of the worm itself. In the device above described, the entire mass of fuel is cut in two by the V- shaped-rtrogigh 82, and at this point where the fuel is broken up, an additional supply of air is delivered where it is most needed. This additional supply of air which passes through the trough 82 tends to `keep the exposed materials in the tuyre bridge below a dangerous temperature. In fact, this is true of the other kinds of tuyres above described.

In order to extend the lire area and to prevent any incompletely consumed materials from falling over the side of the walls 7 5 and 7 6 into the ash pit, there are provided the auxiliary tuyres 91 which insure complete combustion of all fuel before it can possibly escape into the ash pit from which the ashes can be removed in the customary manner.

By manipulatingr the rods 101, which are attached to the sliding doors 96, the supply of air to the auxiliary tuyres 91 can be closely regulated, and since it is evident that it is necessary to supply air to the major portion of the fuel being consumed before it reaches the outer row of tuyres, it is also necessary that the inner tuyres must be supplied with air, and it is for this reason that the outer tuyres are supplied indirectly from the -inner chamber lrather than directly from the fan, although this could be accomplished without departing from thefspirit of our invention.

We are aware that many forms of under feed stokers have been vconstructed in the past; we therefore do not claim such devices broadly, but we do intend to cover allsuch forms and modications as fall fairly within the appended claims.

We claim:

1. A coal burner having, in combination, a plurality of tuyres forming an enclosed area; a plurality of auxiliary tuyres surrounding said first mentioned tuyres and spaced therefrom; brickwork supporting said tuyres, said brickwork having a central Y opening connecting with saidfirst mentioned tuyres and having a passageway formed therein adapted to supply air to said last mentioned tuyres.; a fire pot in said central opening; a fuel feed worm adapted to feed fuel upwardly into said fire pot; a fan arranged to deliver air to said tuyres; and neans for regulating the flow of air from said 2. A coal burner having, in combination, a plurality of tuyres forming an enclosed area; a plurality of auxiliary tuyres surrounding said flrst-mentioned tuyres and spaced therefrom; brickwork supporting said tuyres, said brickwork having a central opening connecting with said first mentioned tuyres and having a passageway formed therein adapted to supply air to said last mentioned tuyres; a lire pot in said central opening; a fuel feed worm adapted to feed fuel upwardly into said fire pot; a fan arranged to deliver air to said tuyres; means for regulating the flow of air from said fan; and means for forcing air into the fuel being fed by said worm at a higher pressure than has the air being delivered to said tuyres.

3. A coal burner having, in combination, a ire pot; a brick wall surrounding said lire pot and spaced therefrom having a passageway formed around its upper portion; a worm housing passing through said brickwork and opening into said lire pot; a worm in said housing for feeding solid fuel into said fire pot; a row of tuyres covering the space between said brick wall and said fire pot; a row of auxiliary tuyres around said first mentioned tuyres over the passageway in said wall; dampers in said wall adapted to control the flow of air from the fire pot containing opening into said passageway; a fan; an air duct leading from said fan to saidire pot opening; an air pipe taking higher velocity air from said fan and discharging into said worm housing; a motor directly connected with said fan; a feed mechanism intermittently driven by said motor for rotatsolid fuel burner which receives its fuel thru a conduit from a hopper and in which air is delivered thru an air duct to the combustion chamber from a blower; which consists in by-passing a quantity of air from the blower to the fuel conduit in such a manner as to create, in the conduit between the hopper and the combustion chamber, a zone of greater pressure than exists in the air duct adjacent its point of discharge into the combustion chamber. U

6. In a furnace, masonry providing a plane fuel supporting surface bounding a central air chamber and broken by an auxiliary air passage, a retort in the air chamber, tuyre blocks surmounting the retort and in communication with the air chamber, a series of tuyre blocks across the auxiliary air passage, means for feeding fuel to the retort,

and means for delivering air under pressure to the air chamber and to the auxiliary air passage.

7. In a furnace, two spaced rows of fire brick, an ash space to one side of both rows, a series of blocks bridging said rows so as to prevent fuel falling into the space between the lire bricks, said blocks having tuyre openings discharging across the fuel supporting upper surface of the lire bricks on each side of the blocks, whereby burning coal passing over both rows of iire brick to the ash space will be completely consumed because of the auxiliary air discharge thru the tuyre openings.

8. In avfurnace, a retort, a tuyre directly above the longitudinal center line of the rctort, an auxiliary tuyre spaced from the retort, fuel supporting surfaces on both sides of the auxiliary tuyre, said auxiliary tuyre discharging air toward the retort and also in the opposite direction whereby the com` bustion area is extended and complete combustion of the fuel is assured.

9. In an underfeed stoker furnace, a retort, a conduit communicating with said retort, a fuel hopper, means for delivering fuel from said hopper thru said conduit to said retort, a blower, means for conveying air from said blower to a point above the retort, and additional means connecting the blower to said conduit between the hopper and retort to create an air pressure in the conduit greater than the pressure of air at the point of combustion.

10. In an underfeed stoker furnace, a retort, a tubular conduit communicating with said retort, a hopper, a worm in said hopper for delivering fuel from the hopper to said retort, a tuyre bordering the retort, a blower, a passage connecting said blower and tuyre and a pipe leading from the blower at the point of highest velocity of the air and injecting it into the conduit between the hopper and retort to create in the conduit a zone of higher pressure than exists in the combustion chamber. v

l1. In combination, a furnace chamber, a retort within the chamber, a tuyre for delivering'air under pressure to the fuel bed above said retort, a fuel conduit passing thru the furnace wall and discharging to the bottom of the retort, a blower spaced from the wall of the furnace chamber, an air duct leading from said blower to saidtuyre, a pipe independent of said duct, for delivering air from the blower to said conduit at a point outside of and adjacent said furnace wall, and means for creating in said pipe a pressure greater than the ressure which exists in the combustion chamber whereby the air passing thru the pipe into the fuel conduit will drive thru the fuel conduit with the fuel such gases as may be discharged from the combustion chamber and would otherwise tend to pass thru the fuel conduit into the furnace room.

12. In an underfeed Stoker furnace, a retort, a' tuyre surrounding said retort, a V- shaped trough open at both ends extending longitudinally of the retort, a tuyre supported by said trough and extending the length of the retort, brickwork surrounding said retort and tuyres, and an auxiliary tuyre surrounding said brickwork, additional brickwork surrounding said auxiliary tuyre, and means for delivering air to all of said tuyres.

13. The method of preventing gassing of a coal burner of the type in which the combustion takes place in a retort chamber to which the fuel is delivered thru a fuel passage leading from a hopper within a living room and in whichV air for combustion is delivered to the retort thru a passage separate from the fuel passage by means of a blower, which consists in deliveringair directly from said blower to the fuel conduit between the retort and the hopper at such a pressure as to cause a constant flow of air thru the fuel conduit toward the retort to prevent the passage of gases from the retort thru the hopper into the living room.

14. The method of preventing gassing by a solid fuel burner which recelves its fuel thru a fuel conduit from a hopper, and which receives its main combustion air thru an air duct leading from a blower to the retort of the solid fuel burner, said air duct including no portion of the fuel conduit; which consists in discharging air into the fuel conduit at such a pressure and in such a direction as to cause a flow of air thru the fuel conduit in a direction from the ho per to the burner, the pressure of the air in t e conduit being greater than that at the outlet of said duct so as to drive the heat released volatile gases thru the burning fuel and also to furnish auxiliary air for combustion.

CYRUS J. PARKER.

CLARENCE T. BURG.

ARTHUR O. DADY.

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