US3038422A - Reciprocal grate stokers - Google Patents

Description

Filed Jan. 11, 1960 3 Sheets-Sheet I1 /NVE/VTOR ESL/E E GOUGH s QQ L. F. GOUGH 3,038,422

5 Sheets-Sheet 2 WA/ A AAAj/ 4.3/

`fune 12, 1962 l RECIPROCAL CRATE STOKERS Filed Jan. 11, 1960 ATTORNEY June 12, 1962 l.. F. GOUGH 3,038,422

RECIPROCAL GRATE STOKERS Filed Jan. l1, 1960 3 Sheets-Sheet 3 FIG. 5

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ATTORNEY i rates My invention relates generally to improvements in solid fuel stokers for furnaces and the like, and has particular reference to grate assemblies and operating means therefor.

Briey and generally stated the present invention has for its primary object to improve over the reciprocal grate bar-incorporating assembly and operating means therefor which is disclosed in my Patent No. 2,695,575, dated November 30, 1954.

More specifically, the invention contemplates, in a reciprocatory grate bar-incorporating assembly, novel and highly eicient long lived means for supporting and simultaneously reciprocating in opposite directions adjacent ones of one or more of a longitudinal series of fuel bedcarrying and rearwardly actuating grate bars.

Various other objects yand advantages of the invention will be referred to hereinafter or will be readily apparent to those versed in the art upon reference to the accompanying drawings forming a part of this specification, in connection with the detailed description thereof.

As required by the patent statute, I have illustrated in the accompanying drawings a now preferred example of the invention, it being understood that invention resides in certain novel features of construction, combination and arrangement of the various parts and in modes of operation thereof. But the illustration is to be taken as illustrative, rather than limitative, since it will be obvious to knowledgeable individuals in the furnace and allied fields that the invention is susceptible of other mechanical eX- pressions within the spirit and scope of the subject matter claimed hereinafter.

In the drawings, wherein the same reference characters have been used to designate the same parts wherever they appear in the several views FIG. l is a side elevational view of a stoker fired boiler embodying my invention;

FIG. 2 is an enlarged horizontal sectional view taken on the line 2 2 of FIG. l;

FIG. 3 is a vertical longitudinal section taken on the line 3 3 of FIG. 2 and illustrating the operating means for alternate ones of a longitudinal series of grate members;

FIG. 4 is another vertical longitudinal sectional view on the line 4 4 of FIG. 2, and showing the operating means for the other grate members of the series shown in FIG. 3;

FIG. 5 is a cross-sectional view on a still larger scale and taken on the line 5 5 of FIG. 2. Referring to the drawings by reference characters, and turning to FiG. l, numeral 5 indicates the boiler of a stoker embodying my invention and which provides the fire box 6, base '7, grate assembly 8, fuel hopper 95. The fuel hopper 9 is supported upon the fuel feeding chamber 10 which latter is carried lby the forward end of a base carried grate bar-supporting plate 12 that is incorporated in the `base 7.

Within the fuel feeding chamber 10 works the pusher 11 for supplying fuel to the grate assembly 8 in the same fashion as is described and illustrated in my prior Patent No. 2,695,575, dated November 30, 1954.

FIGS. 3 and 4 illustrate the grate supporting plate 12 as having the depending side and end walls 12a, 12b, respectively, which are supported by a frame that is provided by the Stoker base '7. This base-provided frame comprehends angle-form side bars 13 and end bars 14 which support the depending plate Walls 12a, 12b as tnt shown. Also incorporated in frame 13, `14 is a longitudinally extending bar 13a which is carried by end bars 14.

In carrying out the invention (see FIGS. 1 and 3), I provide the stoker lbase 7 with a forward extension 15 of the base-provided frame 13, 14 heretofore referred to. This forward frame extension 15 has the side members 15a and the outer end cross member 15b.

The forward frame extension 15 provides the bearing member 16 in which is pivoted, as indicated at 17, the rear end of a motor cylinder 18 or the like within which works the reciprocatory piston 19. The outer end of piston 19 is pivoted, as at 20, to the crank arm 21 which is fast on a main rock shaft 22 that is journalled in bearings 22a supported by the side bars 13 of the frame eX- tension 15, as is clearly illustrated in FIGS. 2 and 3.

From the foregoing, it will be understood that reciprocation of the piston 19 rocks the main rock shaft 22 back and forth. A crank 23 which is fast on the main rock shaft 22 is pivoted as at 24 to the depending lug 11a of the fuel pusher 11 as indicated in FIG. 3. Thus the operation of the main rock shaft 22 results in a reciprocatory movement of the pusher 11 to supply coal or other fuel to the rear top surface portion of the grate barsupporting plate 12.

It may be noted at this time that the grate bar-supporting plate 12 is provided with two longitudinal series of aligned transversely extending openings 25. The respective plate openings 25 are covered by grate bars 26 or 27 so that there are two laterally spaced series of the grate bars 26, 27 as is clearly indicated in FIG. 2. Grate bars 26, 27 are arranged alternately in each series and corresponding bars are in end alignment, as shown.

As is usual in the art, adjacent grate bars 26, 27 of each series are reciprocated back and forth in opposite directions and are so formed as to progressively advance the burning fuel towards the rear end of the grate assembly 8.

A description of the operation of the grate bars 27 will now oe undertaken. Since the operating means for bars in each row is the same, a description of one will suiiice `for both. In carrying out this phase of the invention, I provide the main rock shaft 22 with a xedly depending crank 28, the outer end of which is pivoted as at 29 to the forward end of a link 30. The rear end of link 311 is pivoted as at 31 to the upper end of a crank 32 which is fast on the rock shaft 33 that is journalled in bearings 33a, secured =to the undersurface of the eX- tension side members 15a as indicated. The rock shaft 33 has the depending crank 34 to which is pivoted, as at 35, the forward end of a connected linkage .36, 36a which has the pivot connections 37 with the depending crank arms 38 of superjacent rock shafts 39. The respective rock shafts 39 are journalled in bearings 40 mounted on bars 13, 13a and include upwardly extending crank arms 41 which are spaced longitudinally of the respective rock shafts 39. The upper ends of the crank arms 41 of each shaft 39 have welded, or otherwise secured thereto, the rods 42 which Work in the depending slotted lugs 27a of the respective grate bars 27 of each series 26, 27, as indicated in FIG. 3. Thus it will be clear that upon operation of the piston 19 of the motor 13, the aligned grate bars 27 which are alternate ones of each of the longitudinal series of grate bars will be reciprocated back and forth;

Corning now to the operation of the set of aligned grate bars 26 of the two longitudinal grate bar series and turning to FIG. 4, it will `be noted that the main rock shaft 22 has a second depending crank arm 43 pivoted as at 44 to the rear end of a linkage 45J 45a which is pivoted at longitudinally spaced points as at 46 to the lower ends of the crank arms 47. These crank arms 47 are fast on the shafts 48 which are journalled in bearings 49 carried `by the longitudinal base provided frame members 13 and 13a. The rock shafts 43 have the upwardly extending cranks Sil which are spaced longitudinally of the respective shafts 48 and whose upper ends have made fast thereto the rods 51 which correspond to the rods 42 shown in FIG. 3 that are carried by the crank arms 41. The crank-carried rods 51 of FIG. 4 engage in the slots ofdepending lugs 26 of the respective aligned grate bars 26 of each series so that when the main crank shaft 22 is driven, the grate bars 26 will be reciprocated back and forth on the supporting surface of the grate plate 12.

From a comparison of FIGS. 3 and 4, it will be apparent that when, for instance, the grate bars 26 of each grate bar series are being shifted forwardly on the plate 12, the adjacent grate bars 27 of each series will be simultaneously actuated rearwardly and vice versa.

The grate bars 26 and 27 `are duplicates of one another and provide the thickened dual pushing rear edges, the forward edges of the grate bars being thin so as to admit of fuel riding up on same. Also some or all of the grate bars 26, 27 are provided with the inverted frusto-conical openings therethrough for better actuation of the tire bed, and for updraft purposes.

Although not forming a part of the present invention, it will be noted from an inspection of FIGS. 2, 3 and 4 that the grate supporting plate 12 provides the sinous cooling fluid flow or passage coil 52. This passage 52 traverses the portions of the grate plate 12 between the openings 25 therein through which the slotted grate lugs 26a, 27a extend; and the liow of fluid therethrough from a suitable source serves to cool plate 12 and the subjacent space.

As herein shown, passage 52 has an inlet 53 connected to a low part of boiler 5 and an outlet connected to a high part thereof. A suitable pump 55 in the passage inlet 53 provides forced circulation.

The grate bar-supporting plate 12. has a number of important functions aside from its contribution to smooth operation of grate bars 26, 27. For instance, the forward end of said plate 12 constitutes, as indicated in FIG. 3, a support for the fuel feeding chamber 10.

Also the side and end walls 12a, 12b of said plate y1.2 in `cooperation with the novel base 7 provided angle iron frame 13, 14 effects a desirable spacing of the plate 12 and the re bed-supporting grate bars 26, 27 above the grate bar-actuating rock shafts 39, 43, their supporting bearings and the subjacent operating linkage 36, 36a and 45, 45a. Thus heat induced deterioration of the parts mentioned is materially reduced.

The -base 7 provided frame 13, 14, 15 is also an important feature of the invention, it being understood, of course, that the forward motor 18 and main rock shaft 22 are entirely supported on the frame extension 15 which is functionally integral with the main plate 12 supporting portion 13, 14 of said frame. Thus the novel base-carried frame 13, 14, enables me to dispose all of the linkage 36, 36a and 45, 45a at a point very substantially below the fire bed to avoid heat damage thereto.

Further to be noted is the fact that the `grate-supporting plate 12, 12a, 12b is removably supported by frame bars 13, 14 so as to admit of ready access to shafts 39, 48. Expended fuel, usually in the form of clinkers is discharged -from the grate onto the usual dump plate 56.

Having thus described my invention, what I claim and desire to secure by Letters Patent is:

1. In a solid-fuel burning furnace, a support base including at least a pair of spaced, vertically extending, parallel side walls, a pair of horizontally disposed, inwardly projecting, mutually parallel opposed side bars secured on intermediate portions of said side Walls, said side bars including aligned, opposed bearing means, shaft means journaled in said bearing means defining an axis of rotation transversely of said side bars, a substantially planar grate-support plate including a pair of parallel side plates depending from said grate-support plate and including coplanar lower edges removably reecived on said side bars for supporting said grate-support plate a substantial distance above said side bars, said grate-support plate including a longitudinally spaced series of aligned openings, grate bars reciprocally supported on said grate-support plate in operative relation to said gratesupport plate openings, and a longitudinally disposed force-transmitting means disposed beneath said side bars and including vertically extending, oscilatable levers intermediately pivoted on said shaft means, said vertically extending levers including upper terminal abutment means, said grate bars including abutment means extending through said openings and abutingly and removably engaging said terminal abutment means on said vertically extending levers.

2. The structure of claim l; said grate support plate including an extension support portion exteriorly of said base forward fuel-feeding chamber supported on said extension support portion and communicating with the upper surface of said grate support plate, fuel-pusher means in said fuel-feeding chamber for urging fuel onto the upper surface of said grate plate, power means mounted on a portion of said support base, and force transmitting means connected to said pusher means and said force transmitting means for simultaneously operating said grate bars and fuel-pusher means.

3. The structure of claim l; alternate grate bars cornprising two longitudinally spaced, separate series, said force transmitting means including separate linkage members each pivotally connected to the vertically pivotal levers of the grate bars of the respective series for simultaneously reciprocating alternate grate bars of each series of grate bars in opposite directions.

4. The structure of claim 3; said grate support plate including an extension support portion exteriorly of said base forward fuel-feeding chamber supported on said extension support portion and communicating with the upper surface of said grate support plate, fuel-pusher means in said fuel-feeding chamber for urging fuel onto the upper surface of said grate plate, power means mounted on a portion of said support base, and force transmitting means connected to said pusher means and said force transmitting means for simultaneously operating said grate bars and fuel-pusher means.

5. The structure of claim 1; the vertically pivotal levers being disposed in opposed pairs beneath opposite ends of and intermediately of each grate bar, said detachably engageable abutment portions of said grate bars and levers comprising a rod secured at opposite ends to the upper ends of said opposed pairs of levers, said grate plates each including downwardly opening lugs extending into said grate plate openings and removably and pivotally received on one of said rods disposed therebeneath.

References Cited in the file of this patent UNITED STATES PATENTS 945,469 Mapel Jan. 4, 1910 1,440,939 Simmons Jan. 2, 1923 2,276,327 Mayers Mar. 17, 1942 2,385,027 Preston Sept. 18, 1945 FOREIGN PATENTS 438.560 Italy Aug. 17, 1948

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