US1284929A - Self-feeding stoker. - Google Patents

Description

R. s. RILEY.

SELF FEEDING STOEH.

APPLICATION FILED MAY 13, 1.914.

Patented Nov. 12, 1918..

3 SHEETS-SHEET l.

4.. 9 RJ E3 Kl .OY HNA M I G DnNw .mn SEF E l N DnFO Fl LM .LC Sl. L P P A Patented Nov. 12, 1918,

3 SHEETS-SHEET 3.

UNTTED STATES PATENT FFTQE.

ROBERT SANFORD RILEY, OF WORCESTER, MASSACHUSETTS, ASSIGNOR TO SANFORD RILEY STOKER CO., LTD., 0F WORCESTER, MASSACHUSETTS, A CORPORATION OF MASSACHUSETTS.

SELF-FEEDING STOKER.

Application tiled May 13. 1914.

To all whom t may concern:

Be it known that T, ROBERT SANFORD RILEYH a citizen of the United States, and resident of 1Worcester, in the county of iiiorcester and State of Massachuselts, have invented certain new and useful mprovements in Self-Feeding Stokers, of which the following is a specification.

The present invention relates to furnaces and to automatic fuel feeding mechanisms for such furnaces. The type of furnace under this general description to which the invention relates is that in which a fuel feeder introduces fresh fuel into one end of the furnace, and auxiliary means'are provided to further feed fuel during the combustion thereof toward the discharge point of the furnace. The objects of my present invention are to provide in connection with means forregulating and varying the extent of movement of the auxiliary fuel feeding device, safety devices to prevent such improper adjustment of the auX- iliary feeding means vas would cause damage to the driving mechanism; to provide means for breaking and stirring the fuel which is undergoing combustion and is under .the control of the auxiliary feeding means, and to secure this breaking and stirring effect without increasing the rate of feed of the fuel; and t0 provide a means to prevent the sifting of line fuel between the stationary parts of the furnace and the moving auxiliary feeding means, where such feeding means form the boundaries of fuel channels. The precise nature of the improvements constituting my invention and a possible fOrm of means in which such improvements may `be embodied are illustrated in the accompanying drawings and described in the following specification. These drawings show my present invention applied to a stoker of the particular character described in my prior Patent No. 1.090.651 issued March 17, 1914, and the following description explains ak particular embodiment of the invention adapted to that particular Stoker. 1t is to be understood. however, that the principles of my invention are applicable to other types of Stoker and that in illustrating them in connection with Specification of Letters Patent.

Patented Nov. i12, MMS..

serial No. 838.282.

the particular stoker referred to, I have done so merely for the sake of illustration and not with the idea of limiting the invention.

Tn the drawings,

Figure 1 represents a plan view and partial horizontal section of a Stoker of the sort illustrated in the said patent, with my present invention applied thereto.

Fig. 2 is a longitudinal vertical section taken through one of the retorts of the stoker.

Fig. 3 is a plan view on a larger scale of a portion of the stoker showing more clearly the devices to prevent sifting of fuel between the stationary and movable parts thereof.

Fig. 4 is a vertical. cross section of the portion of the Stoker shown in Fig. 3.

Fig. 5 is a cross section on a much enlarged scale illustrating a portion of one of the retorts of the stoker and one of the strips for preventing sifting of the fuel.

Fig. 6 is a perspective view of the external portions of the fuel feeding mechanism illustrating an embodiment of means for preventing injury to this mechanism in consequence of changes in the adjustment thereof.

Fig. 7 is a plan view of the safety finger which forms a portion of this means.

Fig. 8 is an end view of this finger.

Fig. 9 is a plan view of the safety finger and a portion of the adjustable means by which motion is transmitted from the primary fuel feeder to the auxiliary fuel feeder.

Fig. 10 is an end view of one of the adjusting members of this mechanism.

Fig. 11 is an elevation of one of the fuel breakers, which forms a part of this invention, said view also illustrating in longitudinal section the floor 0f one of the. retorts.

The furnace which have chosen to illustrate one mode of application of mv present invention is a three retort underfeed furnace of the sort illustrated in mv patent hereinbefore referred to in which fuel is fed into channels or retorts formed by stationary bottom plates and movable walls, the

latter serving to conduct air into the furnace and also serving as auxiliary7 fuel feedlng means. As each retort is a duplicate of all the others, a description of one is suiiicient for illustration of the present invention. The stationary retort bottom is shown at 3, and is rigidly held by the framing of the furnace in the manner described in my said patent. rlfhe side walls are indicated at 4 and are mounted at each side of the bottom plate, extending both above and below the plate, and are mounted with capability of reciprocating. Air supplying outlet members 5 are mounted upon the upper edges of the walls 4 and extend entirely across the spaces between the walls of adjacent retorts. The bottom plate, walls.. and air supplying members divide the combustion space of the furnacefrom a space 6 beneath. into which air is delivered by a blower 7 or other suitable means.

T he fuel is placed in a hopper 8 in front of the front wall 9 of the furnace and is allowed to gravitate into a pusher guide 10 in which there reciprocates a fuel pusher 11. The guide is in alinement with the retort and the pusher is reciprocated back and forth beneath the hopper outlet by a crank l2 on a drive shaft 13. and a connecting rod 14. T he pusher 11 thus forces the fuel, issuing from the hopper. into the forward end of the retort, and constitutes the primary fuel feeder.

The side walls 4 and air supplying memr lbers 5 of the retort are reeiprocated with'a reduced extent of motion by the primary feeder by connectionsconsistingA of bars 15. connected to the side walls and extending forwardly through guides 16", rods 17, having heads 18 which extend forwardly from the bars 15, and wrist pins 19 which extend from the pusher through slots in the sides of the guide 10, and are provided with apertures or passages through which the rods 17 pass. rThe wrist pins travel along the rods 17 as the pusher reciprocates and give a greater or less extent of back and forth motion to the walls 4 by making contact alternately with adjusting blocks or fillers 20 and with the heads 18 of the rods. The lller blocks are placed removably on the rods 17 between the wrist pins and the adjacent ends of the corresponding bars 15, the extent of the motion given to the side walls being determined by the number of these filler blocks so placed. After being moved inwardly by pressure of the wrist pins during the inward stroke ofthe latter, on the filler blocks, the side walls are withdrawn always to the same point by the engagement of the wrist pinsl with the permanent and rigid heads 18. Thus there is provided a motion reducing drive from the primary feeder to the auxiliary feeding means, adjustable by placing 0r removing filler blocks, to vary the extent of .movement transmitted to the auxiliary feeding means, which as before stated resaca@ are constituted in this particular stoker by present invention consists relates to a safety device for preventing placement or retention of the adjusting blocks 11 in any position except the one in which they are designed to be placed. rlhese adjusting blocks are adapted to be slipped on the rods 17 between the wrist pin and the abutment constituted by the end of the bar 15. 1f the filler blocks should be placed between the wrist pin and the opposite abutment constituted by the i head 18, it is evident that damage might result through the wrist pins continuing to pull upon the side wall after the latter had reached its outward limit of travel. My invention prevents that result by making the blocks of such a character that they can not be placed securely, yor retained, in any other position than that in which they are designed to be placed.

To accomplish this end I make the filler blocks substantially as shown in Fig. 10, each block being in general horseshoe shaped with short legs 21 adapted to straddle the rod 17 and being spaced much more widely apart than the diameter of that rod. The block may be relatively massive in its central portion so that its center of gravity is located at a high point, (for example, approximately as high as the axis of rod 17, when placed in the position shown in Figs. 6 and 9), and in addition it has a projection 22 on the under side of its central portion which prevents the block being balanced upon the rod 17. In other words, the projection 22, which is V-shaped and preferably extends to a point, naturally causes the block when placed onthe rod to move so that the rod is between the projection and one of the legs, whereby the center of gravity of the block is at one side of the point at which the block rests on the rod and the block, if left otherwise unsupported, will swing around and fall from the rod. I prevent this result from occurring at the location where the blocks are intended to be placed, by providing a finger 23, which is formed on a collar 24 having an aperture 25. The collar is placed on the rod 17 and against the end of the bar 15, being secured thereon by a set screw 26 passing through a tapped hole 27 inthe collar into contact with the rod. The finger is maintained at approximately the level ofthe rod 17 by a stud 28 on the collar which enters sockets in the end of the bar 15 and prevents the collar from turning. The linger is so placed on the collar thatvit extends beside and parallel to the rod 17 at such a distance from the latter that the wrist pin 19 may pass it without en' gagement, while it is near enough to the rod to permit the adjustment blocks to straddle both the finger and the rod. Thus when the adjustment blocks are placed where they are designed to go, that is next to the bar l5, they are supported by both the rod 17 and nger 23 in a stable position, but if placed between the wrist pin and the head 18, the block is unstably supported and is caused by gravity to rotate about the rod and fall from the same. This eect occurs because the center of gravity of the block is at one side of the highest point of the rod, and also because either the legs 2l are too short to hold the block on the rod after it has been thus rotated, or the height of its center of gravity causes the b lock to turn through so great an angle that the uppermost leg is brought to the. inclination at which it will slip from the rod. lt is suflicient to secure the effect described if the leg is no longer than the radius of the rod 17, or the center of gravity of the block is above the axis of the rod, The projection 22 prevents the block from being balanced on the rod with its center of gravity directly over the axis of the rod, which is the only position in which the block could remain on the rod without falling olf, but even if the V-shaped projection were not provided, the vibration due to the movement of the rod would immediately cause such shifting of the block laterally as to destroy its balance. rlhus it is made possible to retain the blocks in the position in which they are intended to be placed, and impossible to have them retained in any other position.

Another feature of the invention relates to guard strips or members 29 which l provide to prevent sifting of ine fuel between the bottom and sides of the retort into the air space beneath. hlecessarily some space is left between the edges of the stationary bottorn of the retort and the movablesides in order to prevent binding of the sides when the parts expand upon becoming heated. rlhe guard strips 29 are provided to overlie the narrow spaces beneath the retort bottom and walls and prevent fine fuel from sifting through such spaces. The preferred construction and arrangement of the retort vbottoms and strips is illustrated in Figs. 3, d, and 5, and particularly in lEig. 5 which shows on a large scale one strip and one edge of a retort bottoni and a portion of the adjacent movable wall. The strip 29 rests at its lower edge on the edge portion 30 of the retort bottom or floor in the angle between such portion and an upstanding longitudinal rib 3l on the bottom or floor. lt is retained loosely in this position by bolts 32 which pass through the rib near the base thereof and through the strip near the lower edge of the latter. rl`he upper edge of the strip bears against the adjacent surface of thc movable wall, being retained in that position both by gravity and by the pressure osi of the fuel, Fllhe lower edge of the strip is held so close to the rib 3l that the strip, when left free, can not assume any other position than that shown in the drawings, while at the same time the connection made by the bolts 32 is so loose that the strip may make contact with the wall even whenv the space between the retort floor and wall is the widest. 'lfhus these strips or guards, of which there are two in each retort, one crossing the space between each edge of the retort and the adjacent wall thereof, adjust themselves according to various conditions of temperature, expansion, and width of open spaces between the relatively moving parts, and are eifective under all conditions to prevent the fine fuel from falling through such open spaces into the air space beneath Referring to Fig. L it will be seen that the grate blocks or air outlets 5 on the retort walls are able to move laterally to allow for distortions of the parts of the furnace due to variations of temperatures. rfhe blocks rest loosely on the walls et, and those supported by any one wall are held in alinement by a longitudinal rib 33, on the upper edge of the wail, which enters notches 3l in the upright transverse webs of the blocks, and such notches are wider than the rib. 'llhc excess in width. of the notches over the ribs allows the blocks to shift laterally relatively to the walls in either direction under different 'temperature conditions. These blocks are not illustrated more in detail because they are in other respects substantially identical with the corresponding air outl t blocks shown in my prior patent hereinbefore named. Thus a means is provided by which.V the width of a series of retorts may vary somewhat, extent of variation' depending on the amount of space left between the edges 30 of the retort bottoms and the side walls -e the The guard strips 29 are an important part of this provision for variation in the width of the retorts in that their use permits spaces of as great width as may be required to be provided at the places indicated and prevents the fuel from falling through such spaces or lodging therein and obstructing the movement of the walls.

fr further important feature which is comprehended in my present invention resides in the fuel breaker of which an einbodiment is shown in Figs. l, 2, and ll. This illustrated embodiment of the fuel breaker is a wedge shaped block 35 which rests on the floor of the retort, there being i one in cach retort, and is provided with a stein Btwhieh slides through a guide 3l' attached to the retort tloor. This guide straddles the stem 3G and is beveled on its forward and rear sides, as shown in Fig. 1l, so as to present the smallest possible obstruction to the flow of coal over it. its

' function is to prevent the wedge block from rising into the fuel. rIhe breaker is lfree to move longitudinally of the retort and is therefore carried with the fuel in the direction of feeding movement given to the latter by the initial feeder l1 and the auxiliary feeders, namely the walls 4. The stem 36 of flow of the fuel stream but incapable of Vpushing it in such direction of flow. Thus during the feeding strokes of the pusher or feeder 11 the fuel breaker is propelled only by the fuel and is not advanced at all by the pusher, but on the return stroke of the pusher, the breaker is positively retracted oppositely to the direction of the fuel feed to the forward limit of its travel. 'I` he function of the breaker, as will be evident, is to heave up the fuel and break up the coking masses, making the fuel bed more homogeneous and granular. A. flexible connection, as described, is provided between the pusher and breaker in order that the breaker may not be positively moved in the direction of fuel feeding and so propel the. fuel more rapidly than is desired. If the connection were rigid and adapted to exert a thrust upon the breaker, the latter would have as great a stroke as the pusher, and would feed thefuel already in the retort at a rate greater than the rate of combustion. But by having the connection flexible, (by which I mean without ability to push the breaker in the feeding direction), the breaker is inert in the feeding direction and moves only as fast as it is carried by the advancing fuel, whereby it has no feeding effect and is restricted in function to that 'of heaving up and breaking the fuel. An advantageous feature of the breaker is that it is moved to dierent extents by different kinds of fuel, and to .an extent required by the particular character of the fuel. For example, some kinds of coal tend to form a sticky coke for the breaking up of which a great deal of agitation is needed. Such coal moves the breaker about as rapidly as the coal itself moves in the feeding direction. and gives the breaker its greatest range of movement, which is necessary for the purpose. (')ther kinds of coal-which remain granular flow upwardly from the mouth of the retort and are of the sort which give little or no movement to the breaker, and as these coals require .I little or no breaking, extensive movement of the breaker Ais not necessary. This feature of the invention, however, is not limited to a breaker which is movable, but the claims thereto, except as they are otherwise limited by thleir express terms, are intended to cover any form of breaker used in connection with a retort having a stationary bottom and with propelling means for the fuel, which has the function of breaking up fuel without propelling it, substantially as described, whether it is movable or stationary.

I have already suggested, and I desire to repeat and emphasize that the improvements in which my present invention is embodied, although hereshown as adapted to a particular construction of stoker, arenot limited to use in connection with such stoker; and I desire further to state that the descriptive language in the foregoing specification is not intended to limit the scope of the claims or te restrict the constructions hereinafter claimed to the pal'- ticular stoker vor furnace shown in these drawings and in my prior Patent No. 1,090,651.

What I claim and desire to secure'by Letters Patent is:

l. In a furnace, a retort composed of a stationary ioor and longitudinally movable walls, and guard strips supported adjacent to the edges of said floor and" bearing against said Walls to prevent passage of fuel between the floor and walls.

2. In a furnace, a retort composed of a stationary floor and longitudinally movable upright walls at each side of said floor, i

means loosely connecting said strips to said floor and permitting movement of the upper edges of the strips, said upper edges being arranged to bear against the contiguous retort walls.

3. In a furnace, a retort composed of a stationary floor and movable side Walls, said Hoor being arranged with spaces between its edges and the walls and having longitudinal upright members adjacent to its edges, guard strips supported on the edge portions of the floor and resting on the edge thereof. and fastening devices loosely connecting the lower edge portions of said strips to said upright members permitting lateral swinging movement of the strips about their supporting edges, whereby said strips are adapted to bear on the side walls and to be forced against the latter by the weight of fuel in the retort, and to yield in. response to changes in relation between the floor and walls due to expansion and contraction.

4. In a furnace, a stationary floor member constituting the bottom of a retort, longitudinally movable upright wall members at each side of said floor member constituting the walls of the retort, and air outlet members supported on the upper edges of said walls, the said upper edges and the air outlet members having complemental grooves @Sie Las/ncaa and recesses for alining the outlet members, and said grooves being wider than the ribs, whereby relative lateral movement between the outlet member and lower members is permitted, and guard strips resting edgewise on said floor member near the respective walls, loosely connected adjacent to the supporting edges of the Hoor member, and inclined so as to bear at their upper edges against the adjacent walls.

5. In a furnace, a retort composed of a stationary Hoor and upright longitudinally movable walls, a fuel feeding pusher arranged to propel fuel into one end of said retort, said walls constituting auxiliary fuel feeders, motion reducing connections between said pusher and walls, means for increasing or diminishing the extent of feeding movement given to the walls by the pusher, means for preventing the pusher from exerting withdrawing pressure upon the walls when the latter have reached their normal limit of outward movement. and guard strips mounted on the edge portions of said tloor near the respective walls and bearing against the walls in a vielding manner, to prevent sifting of fuel between the floor and walls and to permit lateral movement of the walls due to expansion and contraction. t

6. ln a furnace having a fuel retort, a reciprocating fuel feeder arraneed to propel fuel into said retort longitudinally thereof., a lfuel breaker located in said retort with freedom to move longitudinally thereof. and a collapsible connection between said breaker and'feeder. whereby the latter positively moves the breaker oppositelv to the direction: of fuel feed during the outward stroke of the feeder. and leaves the breaker free to be propelled bv the fuel during the feedina" stroke of the `feeder.

i'. in a furnace havine a retort composed in part of side walls which are movable longitudinally for feeding fuel.: a primary feeder arrana'ed to iniect fuel into one end of the retort. a fuel breaker in the retort between said side walls. and a flexible connectinfr member ininirw1 .said primary feeder and breaker together. said Flexible member causing the primary feeder to move the breaker positively durinfr the out stroke onlv of the feeder. and leaviuo the breaker free to move with the fuel under propulsion by the retort walls.

8. l'n a furnace havingl a retort composed in part of loneitudinallv movable walls constituting auxiliary fuel feeding means. a primary feeder arranged to iniect fuel into one end of the retort.. motion reducing connections bv which sa'idprimarvfeed er moves the retort walls to an extent less than that at which the feeder moves. a fuel breaker arranged in the retort. and a lost motion connection between said breaker and fuel stationary bottom and longitudinally mova able side walls, a fuel breaker 'supported upon the bottom of said retort and being generally wedge shaped, having its larger end directed in the direction of flow of the fuel stream, and actuating means having lost motion connection with said breaker for -positively moving the `breaker in the direction opposite to the flow of the fuel stream and arranged to periodically permit the breaker to be lmoved by the fuel stream.

l0. ln a furnace, a fuel retort comprising a stationary bottom and sides mounted independently of said bottom with provision for movement longitudinally of the retort. guard members supportednnovably on said bottom adjacent to the opposite walls of the retort respectively and arranged to bear against such walls. a primary fuel feeder mounted reciprocatively in line with the forward end of the retort for injecting fuel thereinto. motion reducing: connections between said primary feeder and the said walls for moving the latter to an extent less than -the extent of movement of the primary feeder. a fuel breaker arranged in the retort and movable back and forth longitudinally thereof. and a lost motion connection between the primary feeder and said breaker 10,

constructed to positively' retract the breaker during the outward or retraeting stroke of the feeder, and being arranged to leave the breaker inert during the feeding movement of the feeder.

il. ln a furnace. a fuel retort constructed of a vstationarv bottom and side walls independent of said bottom mounted at. eachside with provision for movement longitudinally, a fuel pusher recinrocativelv mounted in line with the forward end of theretort for iniecting fuel thereinto. wrist pins proiectine from said pusher to each side thereof, rods extending longitudinally of the side walls from the forward ends thereof and passing through said wrist Tiins. abutments in front and rear of said wrist pins connected with said rods and adapted to be engaQ'ed bv the wrist pins upon opposite strokes of the pusher. fingers proiecting from tbe abutments in rear of the wrist -pins beside and parallel to the respectively adiacent rods and outside of the paths in which the respective ends of the wrist pins travel. adjusting blocks formed to be placed detachably upon the rod and the adjacent linger and to be supported thereby, said blocks being so formed as to be incapable of remaining on the rods adjacent to the forward abutments, a fuel breaker arranged iis in the retort, a flexible connection attached to said breaker' and the pusher respectively and strips connected with the side edge portions of the retort bottom bearing against the respectively adjacent side Walls to prevent entrance of fuel between the edges of the bottom and the Walls.

In testimony whereof I have affixed my VJitnesses:` l

FRED H. DANIELS, IRVING A. TAYLOR.

Images