US1944336A - Grate frame construction - Google Patents

Description

Jan. 23, 1934. I R. WATSON 1,944,336

GRATE FRAME CONSTRUCTION Filed March 25, 1930 INVE TOR M W ATTORNEYT Patented Jan. 23, 1934 UNITED STATES GRATE FRAME CONSTRUCTION Robert Watson, Cleveland, Ohio, assignor, by

mesne assignments,

Company, New York,

Maine to Waugh Equipment N. Y.,v a corporation of Application March 25, 1930. Serial No. 438,757

3 Claims.

' This invention relates to grates of the type used in locomotives, marine boiler furnaces and for other similar heavy duty purposes. More Y specifically, the new grate comprises a frame and grate bars supported therein, the frame having those parts which constitute fuel-supporting surface constructed and arranged to supplyair to the fuel so supported, whereby more efficient combustion is obtained and practically the enlo tire bottom of the fire box is-made effective.

The co-pending application of Thompson, Serial No. 431,282, filed February 25, 1930, contains a discussion of the disadvantages inherent in w grate constructions of the kind now in common use. It is there pointed out that in ordinary grates used in locomotives, for example, the top of the grate frame supports a part of the fuel bed and since the top of the frame is solid metal, only a small quantity of air reaches the fuel on the frame, and this fuel burns sluggishly, with incomplete combustion, loss offuel, and formation of clinkers. When the ordinary frames are used the effective area of the grate is substantially less than the total cross-sectional area of the fire box, since in some grates, the total area of the top of the grate frame may be as much as 15 per cent. of the total area of the fire box. As a consequence the presence of the dead area represented by the top of the frame reduces the efiiciency of the fire box to a marked degree.

The present invention is directed to the provision of a grate in which these disadvantages are overcome and in this grate, the frame itself is so constructed that air is supplied to the fuel supported on the frame quite as effectively as to the fuel carried by the grate bars. In the preferred embodiment of the invention, the frame consists of a web provided with sockets for the v trunnions of the grate bars and between the 40- trunnion sockets, the web carries a pluraity of spaced lugs extending downwardly from the top thereof and terminating at the top in projections which serve as fuel-supporting surfaces. The spaced lugs define passages for the upward 15 flow of air along the web and channels between the projections connect with these passages so that air is supplied through the passages and channels to the fuel on the small supporting surfaces. With this arrangement, the top of the frame is effective grate surface and the fuel throughout the entire fuel bed burns with approximately equal combustion efficiency.

For a better understanding of the invention, reference may be had to the accompanying 55 drawing, in which Fig. 1 is a view of a'frame member of the new grate in side elevation;

Fig. 2 is a plan view of a portion of the new grate;

Fig. 3 is a fragmentary View in side elevation of a center frame member of the invention on an enlarged scale;

Fig. 4 is a plan view of the construction illustrated in Fig. 3;

Figs. 5 and 6 are sectional views on the lines 5-5 and 6-6 of Fig. 3, respectively;

Fig. '7 is a plan view on an enlarged scale of a side frame member of the invention; and

'Figs; 8 and 9 are sectional views on the lines 8-8 and '9-9 of Fig. 7.

Referring now to the drawing, the grate is illustrated as comprising a center frame member 10 and two side frame members 11, only one of which is shown, grate bars 12 being mounted between each side frame member and the center frame member. The center frame member 10 comprises a web section 13 with a bottom strengthening flange 14 and at its top has a plurality of spaced trunnion sockets 15 defined by ribs 16. These trunnion sockets lie at the top edge of the web and the web is strengthened by ribs 17 extending downwardly from the bottom of each rib 16 of a socket. Between the sockets, the frame may have openings 18 for lightness, these openings being defined by strengthening ribs 19. Along the upper edge of the web. are spaced lugs 20, these lugs having a decreasing width in a direction downward from the top of the frame to define air passages 21 between them which gradually decrease in size toward the top of the frame. At the top of each lug there is an upstanding projection 22, the top of which provides fuel-supporting surface. These projections taper in size in an upward direction so that their tops are of substantially less area than their bases. The top of the web member of the frame, as indicated in Fig. 6, is formed with sloping surfaces 23 between adjacent projections, these surfaces being inclined downwardly away from the center line of the web. The lugs in the two rows on opposite sides of the web are in registry and between the projections on each pair of registering lugs, there is formed a channel 24 for the flow of air. As indicated in Fig. 3, each channel is formed with surfaces 25, which incline down toward the space between adjacent projections.

The center frame member is provided with supporting lugs 26 at its ends and it is preferably made with its greatest width at its mid-point, as illustrated in Fig. 1, the width of the frame defob creasing from the mid-point toward the ends. The top of the center frame member is sufficiently wide so that the trunnion sockets are long enough to receive the trunnions 2'7 of a pair of grate bars which lie in alignment at opposite sides of the frame member.

Along each side of the fire box is mounted a side frame member 11 comprising a web 28 which is provided along its inner face near its top with lugs 29 spaced apart to define air passages. 30 between them. Each lug has a projection at its top similar to the projections 22 at the tops of the lugs on the center frame member and the face of the web is cut away at 31 between adjacent lugs to form downwardly sloping surfaces leading to the passages 30. The top of the frame member is provided with trunnion sockets 32 at suitably spaced points.

In installing the new grate, the side and center frame members are mounted in position in the usual way and thereafter the grate bars are placed in the frame with their trunnions supported in aligned sockets in the center frame member and one side frame member. These grate bars may be of any suitable or convenient construction, although I prefer to, employ that disclosed in the Buckley application, Serial No. 338,352, filed February 8, 1929.

It will be observed that the top of the grate frame is no longer solid but fuel is supported thereon on a multiplicity of relatively small surfaces which form the tops of the projections 22.

The fuel on the frame is, therefore, in contact with dead surface of only relatively small area and air may flow to the fuel on all four sides of each projection. Air flows .up through the passages 21 and 30 to the fuel and also flows over the top of the web of the center frame member and laterally through the channels 24. The distribution of air obtained in this manner insures that the fuel supported on the frame will be burned with substantially the same degree of efficiency obtained in those parts of the fire bed which are supported on the grate bars. Therefore, the top of the grate frame instead of representing dead area throughout the grate which reduces the total efficiency of the grate now serves as active combustion surface. In addition, the provision of means for supplying air to the fuel on the grate frame prevents the frame from burning out and the life of the equipment is thus substantially lengthened. The lugs and projections which are formed at the tops of the frame members may be readily formed during the casting of the members and thus do not add substantially to the cost of the complete grate.

What I claim:

1. In a grate, a frame member comprising a web having spaced trunnion sockets in its upper edge in part defined by outwardly projecting ribs, rows of spaced lugs on opposite faces of said web near the top thereof, the lugs on opposite faces of the web being in registry and adjacent lugs in a row defining vertical passages for the flow of air between them, a projection extending upwardly from the top of each lug to provide a fuel support, and a plurality of approximately horizontal air channels across the top of said web between adjacent projections and also between registering projections, said channels communicating with said air passages.

2. In a grate, a frame member comprising a web having trunnion sockets formed in its upper edge, and rows of spaced lugs on opposite faces of said web andintegral therewith, said lugs extending vertically and terminating adjacent the top of the web, the lugs on opposite faces of the web being in registry, fuel-supporting projections, each extending upwardly from the top of a lug,

each'projection having a top surface of less size than the top of the lug, air passages between adjacent lugs for leading airto the fuel supported on said projections, and air channels between adjacent projections and also between registering projections on opposite sides of said web, the bottoms of said channels leading downwardly from the mid-points thereof to form surfaces along which ash may slide.

3. In a grate, a frame member comprising a web having a portion at its upper edge of gradually increasing thickness in an upward direction, open top trunnion sockets spaced at intervals along the top of said member, each socket having one end closed by a portion of said frame member and at least part of each socket lying within said portion of increasing thickness, and a plurality of spaced vertical lugs projecting outward from said portion of the web, said lugs providing vertical air passages between them, and the top of the member between adjacent lugs being cut away to form approximately horizontal air channels for flow of air from said passages over the top of said member.

ROBERT WATSON.

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