US2278317A - Grate structure - Google Patents

Description

'.J. w. HULsoN March 3l, 1 942.

@RATE STRUCTURE Filed July 3o, 1940 wmves J. w. HULSON GRATE STRUCTURE Filed July 30, 1940 March 31, 1.942.

2 Sheets-Sheet 2 JOM lmf. Huw/sn 'onere sran f Y .lohn W. Hudson, Keoimlx, Iowa, assigner to iiulson Grate Gompany, Keokuh, iowa yimplication July 30, 1940, Serial No. 348,473

i Claim.

The invention relates to a locomotive grate structure of the general type disclosed in my U. S.

4Patent No. 2,009,450 of July 30, 1935, in which various grate sections were formed of fingers as-4 ,of rigging fire box, and this condition was aggravated with wear of trunnions, pivots, etc. Such Causing one end of the fingers of grate section to rise and the other end of iingers of the next grate section to lower,y crestraight-draft openings through which some ofthe draft air could pass through the grate withoutbeing subjected to .the bailling action of the tuyeres. While these straight-draft openings were not objectionable in the era ln which the aforesaid patent issued,'they later caused a great deal of trouble and fuel loss when locomotive speeds and loads were increased and ne fuels, often screenings of very light sub-bitumi nous coal, were used. Under these conditions, quite an amount of fuel was lost to the ash pit i rough the aforesaid straight-draft openings when standing by, and similar'loss often occurred when running with light draft. Moreover, when operating at high speeds and under heavy'loads requiring forcible draft, the unbafhed draft air passing through said straight-draft openings, would carry burning fuel from the grate through the locomotive flues and stack, not only wasting .i'uel but causing slagging of ilues, and cinder cutting. The present invention aims to so improve the grate finge-r of' the aforesaid nt as to overcome the above discussed dimand extended use of ylocomotive grates ving the improved ngers, has proven that the ed end has Ybeen attained.

with' the 'foregoing ln view, the invention redescribed and claimed, description being accom- 'A preferred construction has been illustrated and will be rather specifically described, with the understanding, however, .that within the scope of the invention as claimed, variations may be made. While the description will relate to a structure in which each grate section includes separate fingers on a finger bar, it is to be understood that the improvements are equally applicable to a unitary grate section.

Each grate 'section in the present disclosure comprises a finger bar II) and a plurality of 1ingers ll mounted thereon, the pivots of the finger bars being denoted at I2. These finger bars are provided with the usual downwardly projecting arms I3 which are pivoted to the conventional shaker rigging it.

Each 'finger lI comprises an enlarged head l5 extending longitudinally of the upper edge of a vertical web I6, and said head consists of a longitudinal'ridge Il and ribs I8 extending longitudinally of the lower portion of said ridge. The ridge lll is centrally located andthere are two .of the ribs'it projecting laterally from the plis-.hed by reference to the accompanying drawings.

Figure i is a fragmentary top plan view showing a grate constructed in accordance with the present invention.

Figure 2 is a vertical longitudinal sectional l view on line 2-2 of Fig. l showing the grate secopposite sides of` said ridge. When a plurality of the fingers H are assembled in side-to-side contact upon a finger bar I0 to form a complete grate section, the ribs I form the bottoms of airconducting valleys I 9 between the fire-supporting yridges I1. The valleys I9 have suitable air inlet openings or tuyres 20 lwhich baffle and diffuse the draught air drawn through. the grate under the infiuence of the locomotive exhaust, and the fire-supporting ridges Il are formed with transverse air-conducting channels ZI. Everything so far described is disclosed in the above mentioned patent. My improvement, however, resides in novel structure including end Walls 22 `for the Valleys I9, said end walls being joined to the ridges II and to the lateral ribs I8. Each end surface of each finger head I5 consists' of an upper half lle disposed substantially in a ltransverse plane inclined in one direction, and a lower half lll disposed substantially in a second transverse plane Vinclined in the other direction, said upper and lowerr halves converging to a transverse horizontal ridge line 23 at the extreme end of said head I5. The end walls 22 at opposite sides of the ridge Il extend upwardly from the ribs i8 to the ridge line 23 and the outer transverse sides of these walls form portions of the inclined lower half I'Ib of the above described end surface of said head I5.

When the grate sections are in cold grate position or otherwise in slightly tilted position as seen in Figs. 2 and 3, a certain distance 25 (Fig. 3) exists between the end wall tips 23 at one end of the valleys I 9 of any grate section, and the adjacent wall heels 24 of the next grate section. This space, due to the provision of thev inclined walls 22, is considerably less than the shortest distance which would exist between the adjacent ends of the valley bottoms I8, were said Walls 22 not employed. Thus, with the improved end structures including these walls, there will be less loss of fuel between grate sections when these sections occupy cold grate position, and as the re is started and a bed of coals forms on the grate, the expansion of the ire box and the shaker rigging il will bring the various grate sections to substantially horizontal position for operation. Also, during operation, should the grate sections again become slightly tilted, no

straight-draftV openings of objectionable size will be `formed between them and, therefore, the

previous difficulty with respect to stack loss, cinder cutting and flue slagging, will be overcome. The walls 22 do not materially interfere with shaking the ash through the grate nor with dumping the fire and they provide an increased vertical section at the ends of the ngers which will increase the life of the latter in addition to giving the above describedadvantages.

In Fig. 3, in order to emphasize the extent to which the distance 25 is decreased over the distance which would exist if the walls 22 were not used, I have placed dotted lines 21 on the view, even with the upper sides of the ribs I8. By considering the walls 22 cut off along the dotted lines 21 and comparing the distance 2B which wouldV then exist between the fingers of adjacent grate sections with the latter tilted, with the distance 25 which would exist when using the walls tion in the space between adjacent grate sec tions, when in cold grate or other slightly tilted position, has been effected, to prevent fuel from sifting into the ash pit and to prevent stack loss, cinder lcutting and ilue-slagging.

While it is to be understood that am not restricted to exact proportions or dimensions, I have found that excellent results exist when each wall 22 extends above the rib i8 a distance substantially equal to the vertical thickness of said rib and when the inclined surface Hb is at substantially 120 to the'lower side of the rib 48.

tially in a second rtransverse plane inclined in the other direction, said upper and lower halves converging to a transverse'horizontal ridge line at the` extreme end of said head, ,said ridge line 'being in a plane above the upper sides oi' said ribs, and transverse end walls integrally joined .to vsaid ribs and to the lower portions of the lateral sides of said fire-supporting ridge, said end y walls extending upwardly from said-ribs to said 22, it may be readily seen that a marked reduc transverse horizontal ridge lines at the extreme ends o! said head andy having outer sides' forining portions of said inclined lower halves of said end surfaces of said head.

JOHN W. HULSON.

Images