US2255481A - Retort for coal stokers - Google Patents

Description

Sept. 9, 1941. c. L.. CROWLEY RETORT E OR 'COAL STOKERS Filed Nov. 7, 1938 'NTOR Patented Sept.A 9,

UNITED STATES." Farris-1511 oFFlcE BETORT FOB COAL STOKERS Charles L. Crowley, Philadelphia, Pa., asslgnor to Anthracite Industries, Inc., New York, N. Y., a corporation of Delaware Application November 7, 1938, Serial No. 239,209

9 Claims.

Y `The presentrinvention relates to coal stokers and more particularly to a novel retort for use therewith.

In coal stoking equipment for household heaters and boilers it has been the general practice rectangular shape and made of suitable heat re- (Cl. 11o-32) lsistlng material to provide a fuel supporting and burning surface or grate I which forms a continuationof a way or track II leading from the longitudinal coal receiving side of the retort, this track Il as shown by way of vexample is in to employ a retort of circular shape because it the form of a ramp or upwardly inclined plane lends itself to fairly uniform distribution of the surface over which the fuel travels. The grate coal, a more or less even fuel bed, and the ready I0 is provided with a plurality of tuyres I2 suit- Atrimming off of the ash by gravity, the motion ably distributed throughout the surface for the of the retort, or the use of a mechanical scraper. passage of air as delivered under forced draft While such retorts function efficiently incombusfrom a wind-box I3 which extends beneath the tion chambers which are circularincoss-section, f grate I0 as will be seen. An air inlet I4 serves a very different result obtains where the cointo admit air to the wind-box I3 and is in commubustion chamber is of oblong contour. In such nication with a suitablev blower (not shown) or case it is usually impossible to install a round other source of forced draft. A fuel inlet I5 comretort of suflicient grate size to burn the required municates with one end of the retort in substanamount ofl coal per hour necessary to produce the tial register with the coal receiving space I6 steam output for which the boiler was designed. formed by the semi-circular side wall Il. The limiting dimension of course is the width of For feeding fuel to the aforesaid space I6', the oblong combustion space. To install two the form of the invention shown in Figs. l to 3 circular retorts requires two stokers and makes utilizes a worm I8 coaxiaily mounted in a pipe 20 the expense for home use prohibitive. On the which extends into the fuel bin, this latter being other hand if a retort is installed which correusually adjacent to the furnace. In the present sponds to the oblong or rectangular shape of the construction the worm shaft 2| extends lengthlcombustion chamber there at once arises probwise of the retort to project from the end where lems of operation not heretofore solved, for exarnit is arranged to be driven from the Stoker motor. ple an effective feeding means which will uni- As shown this end of the shaft 2| is journalled formly distribute the fuel; an economical and in a bearing 22 formed by a'i'lller block 23 having efficient means for removing the ash from four an inner curved face 24 disposed in the path of sides; how to prevent banking of fines, and many the moving fuel. After the fuel has been delivother details heretofore presenting unsolved ob- Aered within the fuel inlet l5 provision is made for stacles to the use of a rectangular retort. distributing it throughout the length of the re- Some of the objects of the present invention ceiving space I6 in such a manner that the re`- are to provide a new and novel retort for use with sulting fuel bed on the grate III is of substantially coal stokers; to provide a retort which will operuniform depth. In the present instance this even ate a rectangular heater or boiler efciently; to distribution of the entering fuel is accomplished provide a rectangular retort wherein provision by a variation of the diameter of the worm nights, is made for equal distribution of fuel and a uniand in the preferred construction changing the form fuel bed obtained under burning conditions; character of the worm itself. Thus where the to provide for the economical and eflicient remainfuel feeding wormla has flights of two inch moval of ash from a rectangular retl'li; and t0 diameter and of the usual plane surface spiral, I provide other improvements as will hereinafter the grate' feeding worm has nights farmed. of appear, round rod 25 of, for example, three eighths diam- `In the accompanying drawing Fig. 1 represents eter and asecond round rod 26 of, for example, a plan of a rectangular retort embodying one one quarter inch diameter. 'I'he two rods 25 and form of the present invention; Fig. 2 represents 26 are wound as a continuous spiral about the a section on line 2-2 of Fig. 1; Fig. 3 represents shaft 2| and, preferably, have the same pitch as a section on line 3`3 of Fig. 1; Fig. 4 represents that 'of the worm I6, though this is not to be a longitudinal section of a retort embodying the taken as a necessary arrangement. As shown the invention equipped with a pusher type of fuel iiight rods 25 and 26 are welded to the shaft feed; and Fig. 5 represents a sectionv on line 5-5 2| with the larger diameter rod 25 joining the of Fig. 4; f worm 'I8 and the smaller diameter rod 26 termi- Referring to the drawing, one form of the presnating in close proximity to the curved face 24 -ent invention consists of a retort of generally of the block 23.

In order to control the thickness of the fuel bed,

an upwardly inclined plate 21 is located above the grate worm and. as shown, is substantially paralll to the track `II forming a canopy which terminates at the entrance to the grate proper. The free edge of this plate or canopy 21 is turned upwardly as a vertical flange 28, the respective ends of which abut the end walls 30 and 3l of the retort. Preferably this flange 23 is reinforced by .ribs 29 arranged at suitable intervals. Thus as the fuel is delivered to the space I6 the thrust of the worm reacts against the canopy `2l to maintain an even upward travel of the fuel along the track II with that' portion between the track I I and canopy 21 having a mass travel towards longitudinally of the retort and preferably in the wind-box I3. As shown the sections are relatively thin but each includes :agrate surface with tuyres, a wind-box, a fuelreceiving space, canopy, and all elements required`to form the complete retort when assembled and bolted together. This construction makes it possible to vary the size of the retort to meerl conditions by adding or removing sections as necessary.

In the form of the invention of Figures 4 and 5, the retort is shown equipped Witha pusher type of fuel feed, wherein a .reciprocable bar 3l is mounted for operation within the'fuelv receiving space I6. As shown the bar 34 is rectangular in transversesection and'carries a plurality offeeder or pusher elements 35 in the form of -lil-shaped rods or strips which are Welded or otherwise made fast at intervals suitable for efficient feeding of the fuel in the required manner for even distribution.

It will now be apparent that a novel retort has been devised for use in domestic furnaces and boilers having a rectangular nre-box and which Can be definitely proportioned to eiciently distribute the heat to allexposed parts of the firebox. Thisvariationin size takes place by the assembly of the proper number of grate sections to meet .the required condition. It should be noted by the .provision of the offset fuel receiving space that the retort readily takes its centrally disposed position even in boilers having a side water leg since the offset cant thereunder While leaving the grate properly located for effective heating.

In operation the fuel is fed to the receiving space by the worm I8 from the fuel bin and is then handled by the two worms of smaller diameter which are arranged indiminishing order, This construction causes the fuel to be distributed evenly along the entire long side of the fuel passage, while during such regulated distribution the overhanging canopy reacts to the thrust of the fuel to automatically form a fuel bed of uniform thickness and width. 'Ihis results from the uniform lateral velocity imported to the fuel. That portion of the fuel which' travels clear to the end of the receiving chamber is directed towards the grate by the block face 24 and thereby prevents any pockets of nes or the like forming at that place. While the preferred form Shows the wormhaving nights which vary in diameter, the invention is not limited in this particular as flights of different pitch or tapering flights might be employed satisfactorily.

While only a single form is shown in which this invention may be embodied, it is to be understood that the invention is not limited to any specic constructiombut might be applied to various forms without departing from the spirit of the invention or the scope of the appended claims.

Having thus described my invention, I claim:

1. A retort for burning non-coking, non-caking coals, comprising a horizontal grate arranged to receive fuel at one side and to discharge ash at another side, said grate'having a plurality of tuyres therethrough, a wind-box for supplying air to said tuyres, means including an inclined plane surface to feed fuel upwardly to the receiving side of said grate,'means associated with said feeding means for delivering the fuel evenly throughout the length of said receiving side, and guiding means spaced from and substantially parallel to said inclined surface coacting with said feeding means to maintain a substantially uniform depth and width of the fuel bed.

2. A retort for burning non-coking, non-caking coals, comprising a rectangular frame forming an enclosed wind-box having an air inlet, the top of said wind-box forming a grate with tuyres vand an inclined track leading upwardly to said grate, a canopy plate above and parallel to said track forming .a fuel receiving chamber and a fuel passage opening onto said grate, and a fuel feeding means arranged to discharge into said receiving chamber. v

3. A retort for burning non-coking, non-caking coals, comprising a rectangular frame forming an enclosed wind-box having an air inlet, the'top of said wind-box forming a substantially horizontal grate with tuyres and an inclined covered track leading upwardly to one side of said grate, and means to deliver fuel evenly throughout the width of said track.

4. A retort for burning non-coking, non-caking coals, comprising a rectangular frame forming an enclosed wind-box having an air inlet, the top of said wind-box forming a. substantially horizontal grate with tuyres and an inclined track leading upwardly to one side of said grate, means to deliver fuel levenly throughout the width of said track, and means reacting to the thrust of said ldelivering means to regulate the depth of rthe fuel 5. A retort for burning non-coking, non-caking coals, comprising a rectangular frame forming an enclosed wind-box having an air inlet, the top of said wind-box forming a substantially horizontal grate with tuyres and an inclined track leading. upwardly to'one side of said grate, means to deliver fuel transversely across the lower end of said track, and means coacting with the delivered fuel to evenly distribute said fuel across said track.

6. A retort for burning non-coking, non-caking coals, comprising a rectangular frame forming an enclosed wind-box having an air inlet, the top of saidcwind-box forming a substantially horizontal grate with tuyres and an inclined track leading upwardly to one side of said grate, means to deliver fuel transversely across the lower end of said track, and meansin the path of the delivered fuel to prevent improper collection of fuel at the inlet side of said track.

7. A section for a retort for burning non-coking, non-caking coals, comprising a frame forming al bottom, front and rear sides, and a top, said top forming a grate providedx with tuyres and a track downwardly inclined from said grate, and a canopy arising upwardly and extending over said track and spaced therefrom to provide a fuel inlet and control passage for fuel.

8. Ay retort for stoker firing of domestic heaters comprising a substantially horizontal grate unobstructed along one side to discharge ash,means forming a fuel receiving chamber along the opposite side of said grate and below the level thereof, a fuel feeding means operating lengthwise 0f said chamber, and means including a top plate forming anupwardly'inclined fuel passage leading from said chamber to said grate, said top plate functioning as a reacting area to evenly guide' said fuel to said grate.

9. A retort for burning non-coking, non-caking coals, comprising a rectangular frame forming an enclosed wind-box having an air inlet, the top of said wind-box forming a grate with tuyres and an inclined track leading upwardly to said grate, a canopy plate above said track forming a fuel receiving chamber and a fuel passagev opening onto said grate. and a fuel feeding means arranged to discharge into said receiving chamber.

CHARLES L. CROWLEY.

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