Search Images Maps Play YouTube News Gmail Drive More »
Sign in
Screen reader users: click this link for accessible mode. Accessible mode has the same essential features but works better with your reader.


  1. Advanced Patent Search
Publication numberUS1757401 A
Publication typeGrant
Publication dateMay 6, 1930
Filing dateMay 24, 1926
Priority dateMay 24, 1926
Publication numberUS 1757401 A, US 1757401A, US-A-1757401, US1757401 A, US1757401A
InventorsCharles W Thomas
Original AssigneeThomas Stoker Company
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Apparatus for feeding fuel
US 1757401 A
Abstract  available in
Previous page
Next page
Claims  available in
Description  (OCR text may contain errors)

May 6, 1930. c. W. THOMAS APPARATUS FOR FEEDING FUEL 2 Sheets-Shed 1 Original Filed May 24, 1936 gwuantoz May 6, 193%. c. W. THOMAS APPARATUS FOR FEEDING FUEL 2 SheetS-Sheet 2 Original Filed May 24, 1936 Even/0r ate nterl 9 CHAMBS W. THUMAS, U EAST ULE'VETJAND, UHIU, .drSSI'Elll'UTt TO THE THOMAS fiTDEEI-t WUMIPANY, 01F GLEVELANED, UHJDO, .d. UOHJPORATTUN 01E tlllllltll APPARATUS TUB. TEJEDTNG .lf UElh application filed may 19%, Serial No. 11mm. Iltenewed September with.

This invention relates to a furnace, and more particularly to a mechanism for feeding fuel material into the chamber or fuel boa of a furnace and over or onto the grate thereof.

The invention is shown applied to a hot air furnace by way of one illustrative applica tion, but it may he used for other types of furnaces whether the latter are used for heating or power purposes.

@ne object of the invention is to provide an improved feeding nmchanism whereby the power required is materially reduced, which tends to economize on the cost of operation.

as well as to simplify and reduce the cost of construction.

Another ohfrect of the invention is to pro-- vide an improved feeding mechanism in which the fuel material is fed more uniformly andwith less danger of clogging, thereby preventing an undue load on. the power means as' well. as eliminating noise which would otherwise result in the operation of the mech-- portions oft-he fuel material into the tire boa.

Another object of the invention is to pravide an improved hopper, which is shaped and arranged to insure gravitation of the fuel material into feeding position.

Uther objects of the invention will he parent to those skilled in the art to which my invention. relates from the following de scription taken in connection with the accompanying drawings, wherein Fig. l is a sectional view of a furnace having a feeding mechanism embodying my invention including the power means and the control for the latter.

Fig. 2 is a fragmentary section of parts shown in Fig. l, but slightly enlarged.

Fig. 3 is a section on the line 33 of Fig. 2.

Fig. 4: is a view similar to Fig. l, but show ing the feeding member at the end of its force stroke.

Figs. 5 and 6 are fragmentary views, with parts broken away, of the controlling valve.

For convenience T have shown my present invention applied to a circular type of furnace, similarto that shown in my co-pending application Sci. l lo. 727,930, a delivery and spreadingmember of the same general shape and a grate sloped to lit a fire box of circular section, but these parts may be variously shaped and the furnace may be of the steam, hot water or vapor type, as desired.

These parts comprise a hase 1 and a casing 2, which encloses the ash-pit 8, fire boa 4t and a dome (not shown).

The ash-pit 3 is formed hy a casing 3, havmg an inwardly extending flange 3 on which the tire i901; t is supported.

5 indicates as an entirety a delivery and spreading member for the fuel. The fuel delivery and spreading member 5 comprises a trough shaped casting having at itsouter or receiving end a neclr portion 5, which is connected with a fuel feeding or charging mechanism, indicated as an entirety at 6. At its inner end 5, the walls of the delivery memher flare upwardly and outwardly and tcrminate in a horizontal rim that is preferably circular andwhich may be slightly eccentric to the lire-hon if. The rim of the delivery memher 5 is preferably provided with a flange l over which the fuel is caused to move or flow it feeds to and through the delivery memloer. The flange '2' operates to deliver or spread the fuel upon the grate h, and it is supported above and spaced from the grate 8 by posts it, so that air contacts with the fuel as it is delivered over and spread by the flange, the air servin to insure combustion during the delivery of the fuel onto the grate and resulting in maintaining that portion of the fuel which is under active combustion relatively close and substantially concentric to the wall of the fire-box d. The delivery memher is open throughout the length of the neck portion from its discharge opening, this arrangement permitting the fuel to he received in the delivery member slightly below the plane of the delivery opening and to be fed up a relatively low inclined wall, as shown at 5 in Fig. 1. By this arrangement, clogging of the fuel iuthe delivery member is prevented aud the fuel is directed or fed to and over the flange '2' at an angle. As shown in the drawings, the flange 7 is extended around the upper edge of the member 5 to the wall of the firepot, the purpose being to prevent air I provided with lugs (not shown) which extend laterally below the inturned flange 3",

so as to be connected thereto by cap screws. The delivery member 5 is preferably supported by the following instrumentalities: indicates a bar extending across the ashpit 3, having secured to its front end by a screw 10 the lower side of the neck portion 5 and being secured at its rear end by a bolt 10 to the wall or casing 91*. The bar 10 is arranged to form a support for an upstanding member 11, which in turn supports an arcuate device 12. The upstanding member 11 preferably comprises a'pipe section 11 supported on the bar 10 and engaging at its upper end the device 12 and a bolt 11 extending through an opening formed in the device 12 and through the pipe section 11 and an opening formed in the bar 10, and clamped in position with these elements in rigid relationship by a nut 11. The flange 7 is preferably rigidly secured to the device 12 by devices each similar to those connecting the device 12 to the bar 10, to wit, a pipe section 7*, a bolt or screw extending through the pipe section 7* and openings formed in the flange.

7 and device 12 and a nut engaging the bolt and clamping the ring shaped device 12, pipe section 7 and flange 7 in fixed relation, as shown in Fig. 1.

. The grate 8 is of arcuate shape and surrounds the rim of the delivery member 5, but terminates atopposite sides of the neck portion 5*, the space between the ends of the grate 8 being greater than the diameter of the neck portion 5 so that the grate may be oscillated about the axis of the fire-box 4 for a purpose to be later set forth. The grate 8 is disposed in a plane below the flange 7, so that the fuel may be delivered thereto and also t6 provide a space therebetween for the circulation of air to and through the fuel as it is delivered to or falls upon the grate 8 to insure proper combustion. The grate 8 is preferably supported to oscillate on the device 12 by a spider l3 pivotally connected by a bolt 14 to the bar 10 on an axis coincident with the axis of the fire-box 4. For this purpose, each'arm of the spider 13 consists of an inclined section 13 (Fig. 2) extending upwardly from the bolt 14 and a horizontal section 13 which slides on the-device 12.

The grate 8 may be secured to the under surpivot bolt 14 by .hand, but in the preferred form of construction, it is connected to a movable part ofthe feeding or charging mechanism so that in each feeding or return stroke of the feeding member thereof the grate is actuated, that is, oscillated about the bolt 14 relative to the rim 7, to effect its shaking; whereby the shaking of the grate may be correlated to the movement of the fuel charging mechanism and the quantity of fuel supplied thereby-to the delivery member 5 and delivered by the latter unto the grate 8, so that the ashes will be automatically discharged from the grate in accordance with the amount of fuel delivered thereto and'the speed with which burning or consumption of the fuel takes place. The connection between the grate and the feeding or charging mechanism may be similar to that shown in the above referred to application.

The delivery and spreading member 5 and the fuel feeding and charging mechanism 6 are adapted to supply any kind of solid fuel in relatively small pieces. As will be later pointed out, the preferred form of charging plunger to'stop at various points in its force stroke direction, dependent upon the amount or character of the fuel in its path so that it may return and then move forwardly to feed the material or fuel into and through the delivery member 5.

Of the fuel charging mechanism 6, 16 indicates a hopper to receive a supply of the fuel. The hopper is open at its lower end, as shown at 16*, so as to permit the discharge of the fuel into a conduit 17. The conduit 17 preferably comprises a tubular member, the opening 16 thereinto being intermediate its ends. The inner end 17 of the conduit 17 is connected with the outer end of the neck portion 5 preferably telescoping thereinto (see Figs. 1 and 4), an opening 17 being formed in the wall of the casing 3 to receive the tubular conduit 17 18 indicates a feeding member the purpose of which is to feed the fuel material by successive strokes into and through the delivery and spreader member 5. The feeding member 18 is constructed and operated in such manner that in its movement in one direction it acts on the fuel material or a plurality of portions of fuel material in successive order to feed or move the same forward or along the conduit into thedelivery member, so that a suflicient quantity of fuel material is maintained in the delivery member and fresh material supplied as fast as it moves over onto the grate where combustion takes place; Whereas in its movement in the opposite direction, the feeding member 18 is ineffective to move the material and therefore moves rearwardly so as to again engage and move earner the material forwardly and to engage and move forwardly additional material received from the hopper 16. ll accomplish these functions and operations by using a feeding member that is preferably of spiral formation from end to end capable of sliding and rotating in the conduit 17, and moving said member non-rotatively in onedirection to effect feeding movement of the fuel material (see Fig. 4), and moving thedevice endwise and rotatively in the opposite direction, these latter movements being proportional relative to each other so that the endwise movement will be rendered by the rotational movement ineffective on the material. Thus thefeed member is returned to starting position with out correspondingly moving the fuel material, whereby. in its next stroke said member may act on the fuel to feed it forwardly.

As illustrative of suitable means for efiect ing these operations I provide a'mechanism 19 for reciprocating or enclwise moving the feed member and devices 20 which control and effect the non-rotation of the member in its active or force stroke and its rotationiin and during its inactive or return stroke.

The reciprocating mechanism 19 preferably consists of the following: 21 indicates a cylinder having a piston 22 and a rod 23 extending through one head of the cylinder.

By preference the shank 18 of the feed member 18 and the rod 23 may be formed from one piece or rigidly connected end to end. 24 indicates a plurality of plates, (one thereof forming the end wall for the outer end of the conduit 17 to prevent siftings therefrom) formed with aligned openings 23 the walls of which serve as guides for the shank 18*. The plates 24 are supported rigidly relative to the conduit 17 and cylinder 21 and in spaced relation by rods 25 extending through openings in the plates and nuts 26 threaded thereon and tightened against the plates. 27 indicates a closed chamber containing liquid (such as water) and air and connected by a pipe 28 to the cylinder 21 at one side of the piston 22, the pipe 28 extend- --ing to a point below the level of the liquid in the chamber. The air in the chamber 27 is maintained at such a pressure as to maintain the pipe 28 and cylinder 21 full of liquid when the piston 22 is in the position indicated in Fig. 1. 29 indicates a pipe leading from the cylinder, at the opposite side of the piston 22,

. and connected to a liquid supply under pressure, preferably water, and a means 30 for controlling such supply, whereby the piston 22 is reciprocated as will later be set forth. The controlling means 30 will be later referred to.

, Fig. 1 shows the feed member at one exwhfl system and control means 30. The pressure of the liquid will move the piston 22 and through it the shank 18*" and feed member 13 endwise to the position shown in ltig. at. This movement of the piston 22 "will force the water out of the cylinder 21, through the pipe 28 into the chamber 27, compressing the air therein, which built-up pressure is utilised, upon the cutting off of the pressure through the pipe 29, to return the piston 22 and 1 through it the shank 18 and feed member 13 to their first position (see Fig. 1). l have found that the ordinary pressures furnished in city water systems are usually sufficient to effect operation of my feeding mechanism; in

27', which may be constructed to operate automatically at' a predetermined pressure.

The rotating means 20 preferably comprise the following instrumentalities: 31 indicates a clutch element carried by one of the plates 24:, such clement preferably comprising radial teeth 31 cast on the'plate. One side of each clutch tooth maybe disposed at right angles to the plates and its opposite side inclined, in order to insure efiective engagement and disengagement between it and the other clutch element 32. The clutch element 32 com rises a disk surrounding the shank 18 but liaving a key 33 fitting into a spiral slot or groove 34 formed in the shank 18, the pitch of the slot 31- being equal or similar to the pitch of the spiral member 18, so that the rotation thereof will be proportioned to its endwise movement, to avoid movement of the fuel material rearwardly and increased resistance to the return movement of the spiral member 18. The clutch disk 32 is mounted between the clutch element 31 and an abutment 35. which is preferably carried by the adjacent plate 2t, the abutment being spaced from the clutch element 31 a sulficient distance to permit disengagement of theclutch elements from each other. Due to the friction between the disk 32 and shank 18 or the key 33 and walls of the slot 34, the former will move with the shank 18 Accordingly, when the piston -22 and shank 18* start to move toward the left, the disk32 will move to the position abutment 35, the co-action between the walls of the spiral slot 34 and key 33 will rotate the disk and thus permit the shank 18 to move endwise non-rotatively. When the piston 22 and shank 18 start to move from their operateol positions (see Fig. 4) toward the" right,

the disk 32 will move into clutching relation with the clutch element 31, which will hold the disk 32 against turning, and as a result the co-action between the Walls of the slot 34 and key 33 will rotate the shank 18 and effect rotation of the feed member, as already set forth. To reduce the friction between the disk 32 and abutment 35, I may provide between them an anti-friction bearing 36, so arranged thatl'the anti-friction elements will not be displaced by the movement of the disk away from the abutment. As shown, ir the drawings, the abutment 35 is spaced from-the clutch element 31.0nly far enough to permit clearanceof the clutch elements. I As a result but slight movement of the plate 32 is required to effect engagement or disengagement of the clutch elements. Accordingly they will be effective to start rotation of the shank l8 immediately following the movement thereof toward the rightand to release the shank for non-rotative endwise movement immediately following the movement thereof toward the left.

lhe liquid pressure supply and the, control means herein illustrated will form the subject-matter of a separate application, but in order that the same may be fully understood it is briefly described as follows: 37 indicates a pipe leading from a source of water supply till under pressure. 37 indicates a branch pipe leading to a tank 38 where, a normal supply is maintained by a valve 39, controlled by a suitable float 40. 41 indicates an overflow pipe connected to a discharge pipe 42. The pipe 37 is connected to one port of a three- Way valve casing 43. Flow of liquid from the pipe 37 into the casing 43 is controlled by a ball check valve 44 urged toward its seat 44 by a compression spring 45. Be tween the pipe 29, which is also connected to the valve casing, and a return pipe 48 leading to the tank 38, there is provided a second check valve 46 urged toward its seat 46 by a compression spring 47. A plunger 49 is connected to the valve element 46 and is arranged, when the latter is seated, to depress or open the valve element 44", in opposition to its spring 45, and allow Water to flow from the pipe 37 to the pipe 29. (ln the other hand, when the valve element 46 is unseated, the plunger 49 is retracted to permit the spring 45 to seat its valve 44, and in this latter position of the elements, flow from the pipe 37 into the casing 43 is prevented. while water in the pipe 29 is permitted to flow into and through the pipe 48, which operation takes place due to movement of the piston 22 toward the right, as viewed in Flv s. l and t due to the pressure in the tank 24. The operation of thevalves 44 and 46 is edeeted by the tilting of a container 490 and the con trol of such tilting operation is edected by the rate of flow "of water from the tank 38 into the tiltable container 490, which-tvhen tiltedpositively unseats the valve element 46 and permits the cut-ed of the water pres- The container 490 may comprise a cylindrical casing closed except for an overflow ni ple 491 in its upper portion and may e weighted at one end to normally maintain it horizontal, as shown in Fig. 1. 50 indicates a siphon mounted in the container 490 having its intake at that end which tilts downwardly. The siphon 50 is connected by a flexible pipe 50 with the waste pipe 42. 51 indicates a pipe (having a flexible portion) extending-from the bottom of the tank 38 and leading into the container 490 and preferably discharging water into the oppositeend thereof. The flow of water through the pipe 51 is controlled by a valve 52, the operation of which may be effected manually or automatically by a suitable timing or thermostatic mechanism of anydesired construction or both such mechanisms, the connection therewith being made by devices indicated at 53. 54 indicates one or more dams provided in the container 490 and operating to retard the flow of t e water from the weighted end of the conta'ner to its. other end and also permitting the building up of a quantity of water effective to flow quickly to the tilting end of the container 490 after the tilting o eration starts, thereby to accelerate the ti ting movement and produce a positive and quick actuation of the valves 44 and 46.. The container 490 is provided with a pair of'spaced lugs 55 which straddle a Wall 56 on the valve casing 43. The wall 56 is formed with a of the valve element 46. The lugs 55 are pivoted at 57 to the shank. The lower ends of the lugs 55 bear on the upper surface of a plate 59, preferably a plug fitted into the casing 43 and coact therewith to raise the shank when the container 490 tilts. Accordinly, it will be seen that each time the container tilts the valves 46 and 44 will be operated' (the former being opened and the latter closed). After the container 490 tilts, the water therein is siphoned out, following which the container 490 will return to normal (horizontal) osit-ion and thus operate the valves 44 and 46 (the former being opened and the latter closed.)

With the parts iositioned as shown in. Fig. l (valve 46 closed, valve 44 opened and the valve 52 adjusted to the desired extent)- water will flow from pipe 37 through pi e 29 to the cylinder 21;. to actuate by a suitalo e valve the piston 22 toward the left to the Fig. 4 position. Water will also ilow from the tank 38 into the container 490, filling the same until its unweighted end tilts, whereupon the valve silt will he opened and the valve ee closed,

cutting oil pressure on the right-hand face of the piston 22. The back pressure builtup guide slot to slidably receive the shank-44 I in the chamber 27 will then actuate the pis- 1 ten 22 in the opposite direction to the Fig. 1 position and force the water in the cylinder back through the pipe 29 and through the return pipe 48 to the tank 38. The water thus suddenly discharged into the tank 38 overflows through the pipe 41 to set up the ole sired siphoning efiect in the device 50 ll on the siphoning of the water from the container ltlO, the latter will return to normal position, closing the/valve l6 and opening the valve ll", thus re-establishing the pressure supply upon the piston to again actuate it to.

. duly flexed. Also, the container is mounted at such elevation relative to the tank 38 or the normal level of Water therein that when the container 490 tilts, the discharge end of the pipe 51 will be above such water level so as to to stop the flow of water to the container 490. a

The hopper 16 is preferably arranged above the fuel material receiver 17 so that such material may gravitate thereinto or into the path of movement of the feed member 18. I have discoveredthat if at least one of the side walls of the hopper preferably the inner side, wall 16*" or that portion thereof adjacent the delivery opening of the hopper, is inclined, instead of downwardly and inwardly toward the center of the hopper, downwardly and outwardly away from such cen: ter, ll overcome all danger of the material clogging or packing in the hopper and thus insure its gravitation downwardly substantially uniformly into position for feeding.

As will be understood from the drawings, with the wall 16 inclined, as shown, the material at the bottom of the hopper in gravitat ing falls away from such wall, thus leaving space for the material above to fall into and occupy. As a result the upper portion of the material will feed downwardly and tinally drop'into the receiver. The wall adjacent the furnace casing is preferably inclined in the manner just described for the reason that the radiating heat would ordinarily terid to cake the materialfon this wall and the thrusts of the feed member would also tend to pack it thereagainst, but by arrangin this wall in the manner shown l have foun that all of these tendencies as well as-the tendency for the material to pack in the opening from the hopper are entirely overcome.

. The feed member being of spiral form, said member provides (a) a series of shearing edges which tend to agitate the fuel material in the lower portion of the hopper 1d ment against rotation and h a all as it moves relative thereto and thus furment with the material at a plurality of points so that materially less power is required to, feed it forwardly and less danger of a large mass accumulating in front of the feed member results.

To those skilled in the art to which my invention relates many changes in construe tron and widely dld'ering embodiments and.

applications of the invention will suggest themselves, without departing fromits spirit and scope. My disclosures and the descriptions herein are purelyillustrative and are not intended to be in any sense limiting.

What l claim is: V

1. line feeding mechanism, the combination of a delivery member, a conduit connected to said member, a devicereciprocatable endwise of said conduit, means for rotating said device as it moves in one direction, and means for reciprocating said device.

2. A mechanism as claimed in claim 1 in IZvhich saiddevice comprises a spiral mem- 3. A mechanism as claimed in claim 1 in which said rotating means comprise elements that are automatically engaged and disengaged by the reciprocation of said device.

4. A mechanism as claimed in claim 1 in which said rotatin means comprise elements which co-act to e ect rotation of said device due to its movementin one direction.

5. ln mechanism of the class described, the combination of a delivery member, a tubular conduit for fuel material, a supply means leading to said conduit, a spiral member slidably and rotatably fitting said conduit, and

means operating to move said member endlll it'll htl till

lfllll l l til means and operate to agitate the fuel material therein and prevent clogging thereof.

7. A mechanism as claimed in claim 5 in which said operating means comprise a reciprocating. mechanism and elements between a portion of said member and its support which coact to effect rotation during movement ofthe member in one direction.

8. A mechanism as claimed in claim 1 in which said rotating means comprises an element slidably and. rotatably fitting a portion of the feeding device and having a hey disposed in a spiral slot in said device and spaced members either of which is enga ed by said element when said device is move in one direction, one member servin to loclr the elee other member permitting its rotation.

9. ln mechanism of the class described, the combination of a conduit, a'spiral feed member movably mounted in said conduit having a shank, an abutment, a relatively stationary clutch element in spaced relation to said abutment, a clutch element slidably and rotatably fitting said shank, a key and a spirally shaped slot therefor between said shank and last mentioned clutch element, whereby engagement of the clutch elements will hold the last element stationary and eflect rotation of the shank when moved in one direction and release of the clutch elements will permit rotation of the last mentioned element and nonrotative movement of the shank When moved in the opposite direction and means for reciprocating said shank,

10. A mechanism as claimed in claim 9 in which the slotfor the key and thespiral Wall of the feed member have the same pitch.

In testimony whereof, 1 hereunto subscribe my name.



Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2485462 *Mar 1, 1946Oct 18, 1949Nat Biscuit CoCar loader
US2541742 *Jul 20, 1946Feb 13, 1951Wallace & Tiernan Co IncDry feeder
US2800252 *Mar 17, 1954Jul 23, 1957Wahl Eugene APowder-feeding apparatus
US2906417 *Sep 22, 1952Sep 29, 1959Giovanni RossiMaterial conveying device
US3175477 *Dec 6, 1960Mar 30, 1965Halley Cheney AlwynControl means for concrete laying machines
US3963116 *Jun 10, 1975Jun 15, 1976Veli Matti RautiaFeeding screw for slide casting machine
US4241672 *Dec 4, 1978Dec 30, 1980The United States Of America As Represented By The United States Department Of EnergyMethod of regulating the amount of underfire air for combustion of wood fuels in spreader-stroke boilers
US5269233 *Oct 6, 1992Dec 14, 1993Johnson Howard AStoker or particulate conveyor
US5452562 *Jul 25, 1994Sep 26, 1995Versa CorporationMethod and means for composting organic material
US5904031 *Jan 18, 1995May 18, 1999Versa CorporationAgricultural bagging machine
U.S. Classification198/533, 110/286, 110/101.00R, 198/540, 110/109, 110/110, 198/722, 198/772
International ClassificationF23K3/14
Cooperative ClassificationF23K3/14
European ClassificationF23K3/14