US2859743A - Vertical incinerator grate - Google Patents

Description

C. H. BROOKE VERTICAL INCINERATOR GRATE Nov. 11, 1958 3, Sheets-Sheet 1 Filed Sept. 21. 1954 Hill 1 PM H E MR m R M BV r E K R u w c F H M Nov. 11, 1958 c. H. BROOKE VERTICAL INCINERATOR GRATE 3 Sheets-Sheet 2 Filed Sept. 21, 1954 lll CLARKE H. BROOKE INVENTOR.

Nov. 11, 1958 c. H. BROOKE 2,359,743

. VERTICAL INCINERATOR GRATE Filed Sept. 21. 1954 Q :s Sheets-Sheet s FIG. 8

jfl FIG-9 CLARKE H. BROOKE INVENTOR.

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United States Patent VERTICAL INCINERATOR Clarke H. Brooke, Seattle, Wash, prlis fis ep ember 2 A er a 1Nq- 5w:

' 2 Claims. (or. 126-463) My inyention relates to grate construction, and, more particularly, to a cast iron, vertical. incinerator grate. Provision is made to prevent accumulation, of ashes, on the face of the grate by; having. precipitous walls and the grate is formed to. facilitate melding of the same and to simplify its installation in various types of iniasr-a q A vertical grate has advantages overthe conventional horizontal grate, particularly in incineratorsfwhere. considerable ashes are allowedv to accumulate in, the, bottom Of the incinenator between cleanings, and; the furnacev is frequently. overloaded, One difficulty with horizontal grates is deterioration from. having liye coals lying on the, su nfaee. On the other hand/the horizontal grate is less efficient if a layer of ashes and spot is left. on

the, grate. For these reasons, there has been. a more onless, recent development in the use. of verti cal grates a ea ears nd heat sea i this p c tion has several advantages oyer thoseprevious ly; found cu -the market. Prior grates with sloping facesl have ha d the characteristic of formingv a surface for the collection ofmaterjal, particularly ashes, which reduced the efficieney of the air openings orentirely closed them.

Among. other disadvantages, these grates have had irregular. shapes in rear elevation so as. to, make it diflicult for faunason to. brick around, the grate and. some have had difficult structures to mold. i

The objectives, of my inyention include, therefore: to devise a vertical grate constructed so as, t red-uce to a minimum the obstruction of the air openingswith ashes and other debris, to. devise a vertical grate facilitating molding, andinstallation of the same, to provide a grate adaptable to various types and sizes of, incinerators and to improve theconstruction of. the air passageways in such ra es.-

Ihe. invention will be best understood, together with additional objectives and; advantages over previous constructio-ns, from a reading of the following description, when read with reference to the drawings, in which:

Figure l is a front elevational view of a specific embodiment of my incinerator grate;

Figure 2 is asectional. view taken. on line 2 -2 of Figure 1;

Figure 3 is a sectional view taken on line. 3 -3 of Figure l Figure 4' is. a perspective. view ofyone type of an. in-

' cinerator;

ingsof the grate and having washers and nuts 42 abutting r P t nt d. New. 1 .55

The incinerator grate 10 may be installed in various types of incinerators, one formed of brick construction being. shown in. Figure 4, and, the. use. of a steel drum being suggested in. Figure, 7. The incinerator may be of various sizes including largev incinerators for public buildings, manufacturing concerns, grocery stores, and the. like, and also including small. incinerators for households, in the smaller incinerators, i. e., for household use, a, single grate. may be used. of small size, as for example, an 18 inch high 4 inch 1. D., 16 pound grate operative with a maximum incinerator capacity of approximately 12.4 cubic feet. A large size would be 18 inches high, 7 /2 inch 1. D. grate, weighing approximately 38 pounds, and operative singly with approximately 48 cubic feet of capacity. In large incinerators, may be desirable to. use more" than, one grate, as. suggested in Figure 5, or to use superposed grates as shown in, Figure 8.

Referring toFigure 1, the grate 10 is. preferably molded as a one piece unit from. cast iron, as experience has shown that this material has the longest life, againstrusting and deformation from heat, of materials of economical manufacture. No machine work is required after casting. The back 12. is completely, open, and the inner walls 1 4 diy erge from, the forwardside to. rear side 12 so that the mold may be readily removed. It will be understood that thisleads to economical manufacture of the unit because in more closed bodies itis necessary, to use a core which is expensive to make and difficult to remov C ma n ne, o th mos co ly op tions in a foundry.

Referring toEigure 1., side walls 20, 22 are substantially paralleland the bottom edge 24 lies in a plane normal to the side walls. Likewise top wall. 26 lies in a P 21? norm l t sid wal 0.. 2 ex ep o he e i v d topcornersZS. This means that substantially a rectangu lar outlineis presented for bricking-around the same, as will be understood from Figure 5, so that the inner fire b ick in n -0 m e d ound t e s ate h aci tyhs Qa a a r i ak, :2. how n u e 5 may. b ordinary brick, or, in some installations, fire brick. The walls rest on a concrete foundation,

Another representative type of installation is shown in Figure 7 wherein a cylindrical incinerator is formed either by reinforced. concrete, or, as in Figure 7, by the steel drum 36. Again, the fire brick lining 38 can be laid around the grate with a minimum of time because of. its rectangular outline in front elevation. The grate may be fastened in place in this application by a pair of J-bolts 40 having their hooks engaged in one of the front openthe outer surface of, drum 36. The rear edge 12 of the grate lying in a plane normal to parallel side walls 29, 22, grate 10 will fit snugly against a cylindrical surface such as drum 36. This is because the rear edges of side walls 20, 22 lie on lines of generation of'the cylinder. Almost no other shape of grate will conform to the inner wall of the drum and it is advantageous to have this easy and snug fitting to the cylindrical incinerators which are so often used.

The front wall 50 of grate 10 has a series of superposed openings 52'extending from a location spaced from bottom edge 24 to adjacent top wall 26. When considerable consumed material has piled on the floor of the incinerator some of the lower openings may be blocked, and in order to provide some openings that will always be free and also to provide a source of air to gases as they ascend from burning material, it is desirable to have a number of these openings. Eight openings 52 have been shown in the grate illustrated in the drawings and six may be taken as a minimum number for efficient operation of the grate in incinerators. As indicated in Figure 8, it

may be desirable in some installations to increase the number of openings beyond eight. The vertical height of openings 52 is increased from bottom to top of the series. This is desirable for several reasons. First it means that if lower openings are covered because of the level of ashes in the incinerator, the effective total area of openings 52 will be reduced less than if the openings were of equal size. Furthermore, the lower openings nearest to the source of air, such as ducts 54, 56 in Figures and 7 respectively, will be less likely to starve the openings 52 above. Air enters ducts 54, 56 because of the negative pressure created by combustion in the incinerator chamber 58; and the entering air stream will have considerable velocity and pressure, at least at the lower openings. Ducts 54, 56 should be greater in area than the total area of openings 52 appearing on the face of grate 10. As shown in Figure 5, the uppermost edge of the duct should be slightly below the upper edge of the solid lower portion of the front wall 50 so that the duct does not feed directly to the lower openings.

Front wall 50 forms webs 60 between openings 52 and webs 60 extend inwardly forming flanges 62 which terminate in centrally rearwardly opened recesses 64. Recesses 64 have contours similar in plan to the contour of the walls of grate 10. The recesses decrease in size from bottom to top of the series of webs 60. This, in effect, decreases the area of the vertical air passageway in grate having a funneling action maintaining a high pressure of the air from bottom to top, even though air escapes through each opening 52. Fanges 62 lap side walls 20, 22 and have integral connection therewith. Webs 60 are relieved at their upper forward and lower rearward edges as shown in Figure 2.

The outer edges of webs 60 are superposed forming a vertically aligned bank providing no recess or inclined surface outside of openings 52 on which ashes would have any tendency to rest. A less precipitous front face would tend to collect ashes and would form a surface on which debris could build, whereby the openings 52 could be partially covered, reducing the efliciency of the grate. The vertical front wall 50 thereby adds to the efliciency of the grate so that there will be a minimum tendency to cover the openings. As in many installations the incinerator is not tended like a furnace by frequently removing ashes or by carefully loading the same to prevent the fuel from covering the grate, it is quite important to take every measure to prevent blocking of openings 52.

In large incinerators it may be desirable to use two or more grates as shown in Figure 5 and in incinterators of large capacity and considerable height, grates may be superposed as shown in Figure 8. For economical manufacture, without having to make completely new molds for taller grates, the construction of Figure 8 has been devised, working with the usual pattern for one of the grate sizes. The mold is changed on the lower grate 70 by blanking off the two lower openings 52 which would normally appear and providing an opening 72 in top wall 26. Upper grate 74 is formed by reproducing grate 19 from a location immediately below lowermost opening 52 to the top of the grate. As shown in Figure 9, the abutting portions of the grates have a plurality of bead welds 76 securing them together.

This grate has proved to be very eflicient in operation, economical of manufacture and installation, and adaptable to various types of incinerator installations. The usual incinerator owner wants an incinerator that will operate with infrequent cleaning of ashes and which will operate although loaded to the top with debris, and incinerators with the present grate have met these demands. I do not wish to be limited to the exact details of construction shown in the drawings, but Wish to cover those modifications within the scope of the invention which may occur to those skilled in the art, as defined by the appended claims.

I claim:

1. A vertical grate for incinerators, comprising: a hollow cast iron body molded as one piece, the front wall of said body being substantially hemi-cylindrical and merging into substantially parallel flat vertical side walls,

the body having an open bottom and an open back and the edges of the body at the bottom and back lying in planes normal to said side Walls and to each other, the body having a top wall lying in a plane normal to said side walls, the inner surfaces of the side walls flaring to the back edges to facilitate removal of the mold, approximately the lower third of said front wall being solid and of uniform thickness and said body having a series of at least six superposed openings spaced apart up and down the remainder of said front wall, said openings being unobstructed and being horizontally elongated to extend substantially from one side wall to the other side wall, said openings being vertically broader and of increasing effective area from bottom to top of the series, the portions of the front wall separating the openings being in the form of integral webs inwardly extending beyond the interior surface of the lower one-third of the front wall forming flanges instanding into said hollow body, the inner margins of said flanges forming coaxial rearwardly open recesses having substantially semi-circular contours, the recesses decreasing in horizontal area from bottom to top of the series of recesses.

2. A vertical grate for incinerators, comprising: a hollow cast iron body molded as one piece, the front wall of said body being substantially hemi-cylindrical and merging into substantially parallel flat vertical side walls, the body having an open bottom and an open back and the edges of the body at the bottom and back lying in planes normal to said side walls and to each other, the body having a top wall lying in a plane normal to said side walls, approximately the lower third of said front wall being solid and of uniform thickness and said body having a series of at least six superposed openings spaced apart up and down the remainder of said front wall, said openings being unobstructed and being horizontally elongated to extend substantially from one side wall to the other'side wall, the portions of the front wall separating the openings being in the form of integral webs, said openings being vertically broader and of increasing effective area from bottom to top of the series.

References Cited in the file of this patent UNITED STATES PATENTS 45,948 Marshall Jan. 17, 1865 1,097,692 Weaver May 26, 1914 1,428,782 Jouclard Sept. 12, 1922 2,070,894 Gorsuch Feb. 16, 1937 2,565,241 Kyger Aug. 21, 1951 2,625,894 Poor Jan. 20, 1953

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