US2044308A - Stoker mechanism - Google Patents

Description

2 Sheets-Sheet 1 ATTORNEY.

5mm 16, 1936. P. A. KETCHPEL STOKER MECHANISM Original Filed Dec. 16, 1951 June 16, 1935. p KIETCHPEL 2,@44,3@8

sToKE'R MECHANISM Original Filed Dec. 16, 1931 2 Sheets-Sheet 2 INVENTOR.

ATTORNEY.

a I f 53 0/ Patented June 16, 1933 STOKER IVIECHANISM Application December 16, 1931, Serial No. 581,314 Renewed May 1, 1936 13 Claims.

This invention relates to locomotive stokers and particularly to stokers of the type effecting a classification of the fuel.

It is one of the objects of the invention to provide new and improved mechanism in a stoker of the class described for separating the pulverized particles of coal from the coarser particles.

It is a further object of the invention to provide novel and improved means for separately introducing the pulverized fuel particles and the coarser particles into the firebox in a manner whereby the quantity of pulverized fuel particles escaping through the fines and out the stack is reduced to a negligible amount.

It is another object of the invention to provide means for separating the pulverized fuel particles from the coarser particles and for introducing the coarser particles into the firebox through the conventional firing opening and the pulverized fuel particles through openings in the forward portion of the firebox sidewalls.

A further object of the invention is to provide means for separating the pulverized particles of fuel from the coarser particles, and separating the coarser particles into fine and coarse fuel and providing separate means for introducing each into the firebox.

A further object of the invention resides in the provision of means for withdrawing pulverized particles of fuel by suction as the fuel is delivered to the conventional firing opening and introducing it by a pressure blast in the firebox through openings in the forward portion of the firebox sidewalls.

Further objects and advantages of the invention consist essentially in the construction, arrangement, and combination of the various parts, as will become apparent from the following description when read in connection with the accompanying drawings, in which Fig. l is a view in side elevation of the rearward portion of a locomotive with the cab removed and the forward portion of a tender with the invention applied thereto;

Fig. 2 is a view in longitudinal vertical section of a portion shown in Fig. 1 with parts shown in side elevation;

Fig. 3 is a view in rear elevation of the locomotive and stoker mechanism with parts broken away and shown in section; and

Fig. 4 is a sectional view on the line 4--4 of Figure 1.

In the drawings the locomotive generally designated by the numeral l0 comprises a boiler H, a boiler firebox l2, the grate I3 and a roof or arched cover comprising spaced members l4 and refractory material 15.

The boiler H embodies the backwall l6 having a firing opening I! therethrough, a throat sheet #3 oppositely disposed from the backwall and the sidewalls I 9 and 20.

The locomotive is flexibly connected to a tender, indicated generally at 2|, having a stoker fuel transfer conduit 22 extending forwardly from beneath the tender fuel bin (not shown). A riser conduit 23, which may be supported from the locomotive frame 24 by suitable means as by the flexible support member 25, is flexibly connected at its lower end to the forward end of the transfer conduit 22 and extends upwardly and forwardly to the firing opening ll. The upper end portion 26 of the riser conduit 23 flares outwardly providing a wide delivery mouth whereby the fuel discharged by the riser screw 21 drops from the lower edge or ledge 28 of the fiared end portion 25 in a wide, thin sheet or curtain-like form.

Formed with the underside of the riser conduit 23 is a casing 29, opening at its upper end into the firing opening immediately beneath the lower edge 28 of the flared portion 26 of the riser conduit. The lower end of the casing 29 is provided with a pair of diametrically opposite openings 39 and 3|. Conduits 32 and. 33 communicate with the casing 29 through the elbows 34 and 35, respectively, which connect the conduits 32 and 33 with the openings 39 and 3| respectively. The conduits 32 and 33 extend downwardly from the elbows, then outwardly to respective sides of the locomotive, then extend in a generally forward and upward direction and enter the firebox l2 through openings 36 and 37 in the boiler sidewalls l9 and 29 respectively, adjacent the throat sheet I8.

A shaft 38 extends transversely through the lower portion of the casing 29, one end being supported in the bearing 39 formed in the elbow 35, and the other end extending through and beyond the elbow 3 8. Mounted on the shaft 38, adjacent the openings 39 and 3! in the casing 29 are the fans 43 and 4| respectively, the fan blades and direction of rotation being arranged to create a suction in the casing 29 and issue a pressure blast through the conduits 32 and 33.

The shaft 38 is driven from a turbine motor 42 in order to produce the necessary speed of rotation of the fans 40 and 4| to create the required suction in the casing 29. The motor 42 is supported from the locomotive frame 24 by a yieldable member 44. The fuel conveying system of the stoker is operated from its rearward end through a shaft 45 extending rearward from the motor 42 to the rear of the transfer conduit 22. Gearing at the rear of the trough (not shown) and reduction gearing 45 on the locomotive is arranged to provide a predetermined ratio between the speed of rotation of the fans 49 and ll and the speed of rotation of the conveyor screws. If the speed of the fuel conveying screw is increased to deliver more fuel to the firebox the speed of the fans will be increased, producing the greater suction that is necessary to withdraw the pulverized fuel particles from the increased amount of fuel being delivered. Thus, once the proper ratio is determined between the speed of the fans and the speed of the fuel conveying screw, that ratio is always maintained.

The lower forward edge of the casing 29, preferably terminates in a plurality of diverging fingers 61 which extend beyond the forward lower edge 23 of the casing 29. The fingers 31 are cored and provided with the jet openings 48 for the emission of a pressure fiuid blast. A distributor plate Q9, slightly below the fingers ll, extends forwardly beyond the fingers 41. A series of jet openings 50 are arranged at the rear of the distributor plate 49 between the plate and the fingers l'i. Supply lines 5| deliver fiuid pressure, such as steam, to the jet openings 48 and 55.

The forward ends of the conduits 32 and 33 are provided with the nozzles 52 and 53 which penetrate the openings 35 and 37 respectively, and are diametrically opposed to one another. The firebox arch is provided with a transverse depending refractory ridge 54 rearward of the nozzles 52 and 53 and forming with the throat sheet [8 a subcombustion chamber 55 for the pulverized fuel particles issuing from the nozzles 52 and 53.

In operation, fuel is elevated by the riser screw 27 and as it is pushed through the flared portion 26 of the riser conduit 23 and over the ledge 28 it is spread out in a wide thin sheet. The fuel drops onto the prongs or fingers 41 and as it falls the suction created by the fan blades 40 and 4| withdraws the pulverized fuel particles. The coarser particles of fuel are not affected by the fan blades ii! and 4| and fall on the fingers 41. Some of the fuel will drop through the spaces between the prongs or fingers 4'1 onto the rear of the distributor plate 49, whence they are projected over the firebed by the pressure blast issuing from the jets 50. The coarser particles of fuel that do not pass through the fingers 41, roll forwardly over them onto the distributor plate 49 and are projected over the firebed by the pressure blast issuing from the jets 48 in the fingers 47. The blast issuing from the jets 43 is arranged to be at a higher pressure than the blast issuing from the jets 50, since a blast of greater intensity is necessary to project the larger particles of fuel to the forward extremities of the firebox than the finer particles. The distributor plate 49 may be provided with grooves, ridges or both in a manner well known in the art to deflect portions of the fuel to the corners of the firebox and to obtain an even distribution of fuel over the entire firebed.

The pulverized particles of fuel withdrawn by the fans 4E) and ll pass between the blades and are impelled by the current of air passing between the blades through the conduits 32 and 33 into the front of the firebox. In this manner the pulverized fuel is introduced at the hottest part of they fire, so that combustion takes place immediately upon delivery to the firebox, greatly minimizing the loss of fuel unconsumed through the fiues and out the stack. Other factors aiding to eliminate the escape of fuel unconsumed, are, the particular arrangement of the nozzles 52 and 5 53 whereby they are diametrically opposed in opposite sidewalls of the firebox and the formation of the sub-combustion chamber by the refractory ridge 54.

I claim:

1. In a locomotive having a firebox provided with a firing opening and a fire-arch, a stoker comprising a fuel conduit delivering to said firing opening, the forward portion of said conduit flaring laterally, fuel distributing means at said firing opening arranged to project the fuel passing from the forward end of said fuel conduit over the fire in said firebox, a casing having an opening adjacent the delivery end of said conduit, a conduit communicating at one end with said casing and at its other end opening into said furnace at a point beneath said fire-arch and remote from said firing opening, and a fan in said casing arranged to entrain particles of pulverized fuel from the bulk of fuel passing from the forward end of said first named conduit to said fuel distributing means, through said casing for ejecting said particles of pulverized fuel through said second named conduit into said firebox beneath the fire-arch.

2. In a locomotive having a firebox provided with a firing opening, a stoker comprising a conveyor delivering fuel to said firing opening, a casing subjacent said conveyor opening at its forward end in said firing opening, a distributor plate extending forwardly from beneath the forward end of said casing, a conduit communicating at one end with said casing and at its other end opening into said firebox at a point remote from said firing opening, means in said casing arranged to entrain particles of pulverized fuel as the fuel delivered by said conveyor drops onto said distributor plate and arranged to propel said particlesof pulverized fuel through said conduit, and means at the rear of said distributor 5 plate for projecting fuel thereover into the firebox.

3. In a locomotive having a firebox provided with a firing opening, a stoker comprising a conveyor delivering fuel to said firing opening, 5 a casing subjacent said conveyor, said casing opening at its forward end immediately beneath the delivery end of said conveyor, means in said casing arranged to entrain particles of pulverized fuel as it falls by gravity from the discharge 55 end of said conveyor, said entraining means being also arranged to propel the entrained particles of pulverized fuel into the firebox, means beneath the open forward end of said casing arranged to receive and separate the unentrained fuel into fine and coarse particles, means for projecting said fine and coarse particles into the firebox, and a conduit communicating at one end with said casing and at its other end opening into said firebox at a point remote from said fir- 5 ing opening for delivering said entrained particles of pulverized fuel to said firebox.

4. In a locomotive having a firebox provided with a backwall and sidewalls and a firing opening in said backwall, a stoker comprising a fuel conduit delivering to said firing opening, the forward portion of said conduit flaring laterally,

a screw in said conduit delivering fuel therethrough cooperating with said flaring conduit portion to deliver the fuel therefrom in a flattened stream, a casing subjacent said conduit opening at its forward end beneath the delivery end of said conduit, an opening in each of said firebox sidewalls at points remote from said backwall, a pair of tubular conduits each communicating at one end with said casing and at the other end with one of said sidewall openings, means in said casing arranged to entrain particles of pulverized fuel from said flattened stream and to project said particles of pulverized fuel through said tubular conduits into the firebox, and means for projecting the unentrained fuel into the firebox.

5. In a locomotive having a firebox provided with a backwall, a firing opening in said backwall, a fire-arch extending upwardly and rearwardly from the lower forward end of said firebox and terminating short of said backwall forming between said fire-arch and said backwall an escape passage for products of combustion, means for delivering fuel to said firebox including means for separating particles of pulverized fuel from the bulk of said fuel, means providing a passage between said separating means and said firebox, said separating means arranged to project particles of pulverized fuel through said passage into said firebox at a point beneath said fire-arch and remote from said escape passage and means for projecting t e bulk of said fuel into said firebox through the firing opening in said backwall.

6. In a locomotive having a firebox provided with a grate and a backwall, a firing opening in said backwall, a fire-arch extending upwardly and rearwardly from the lower forward end of said firebox and terminating short of said backwall forming between said fire-arch and said backwall an escape passage for products of combustion, means for delivering fuel to said firebox including means for separating particles of pulverized fuel from the bulk of said fuel, means providing a passage between said separating means and said firebox, said separating means arranged to project the particles of pulverized fuel through said passage into said firebox at a point between said fire-arch and said grate and remote from said escape passage and means for projecting the bulk of said fuel into said firebox through the firing opening in said backwall.

'7. In a locomotive having a firebox provided with a fire-arch and with walls, an opening in one of said walls, an opening in another of said walls at a point directly beneath said fire-arch and separated from said first named wall, a grate for said firebox, fuel distributing means at the first named opening above the level of the grate, means for urging fuel to a point adjacent said distributing means and delivering the same from such point into the zone of action of said distributing means for projection over the grate, means acting on the fuel during the passage thereof from said point to said zone to separate fine particles of fuel from the bulk thereof, means providing a passage between said separating means and said second named opening, said separating means arranged to project such separated fine fuel through said passage into the firebox through the second named opening.

8. In a locomotive having a firebox provided with a firing opening in the backwall thereof, a fire-arch and grates, fuel distributing means at such opening above the level of the grate, means for urging fuel to a point adjacent said distributing means and delivering the same from such point into the zone of action of said distributing means for projection over the grate, means arranged toientrain the particles of fine fuel from the bulk thereof during passage thereof from such point to said distributing means, and means providing a passage between said entraining means and said firebox at a point adjacent the front end thereof, such entraining means being also arranged to eject the entrained fine particles of fuel through said passage into the firebox adjacent the front end thereof and beneath said fire-arch.

9. In a furnace provided with a firing opening and a grate, a stoker for supplying fuel to said furnace including conveying means for urging fuel to a point of discharge at said firing opening, fuel distributing means at said firing opening in spaced relation With the point of fuel discharge, said conveying means urging all the fuel toward the point of discharge for passage therefrom toward the distributing means, means arranged to entrain the particles of fine fuel from the bulk thereof during passage of the fuel from the point of discharge toward said distributing means and prior to action of said distributing means on the fuel, and means providing a passage between said entraining means and said firebox, such entraining means being also arranged to eject the entrained particles of fuel through said passage into the firebox out of the zone of action of said distributing means.

10. In a furnace provided with a firing opening and a grate, a stoker for supplying fuel to said furnace including conveying means for urging fuel to a point of discharge at said firing opening, fuel distributing means at said firing opening in spaced relation with the point of fuel discharge, said conveying means urging all the fuel toward the point of discharge for passage therefrom toward the distributing means, means arranged to entrain the particles of fine fuel from the bulk thereof during passage of the fuel from the point of discharge toward said distributing means and prior to action of said distributing means on the fuel, means providing a passage between said entraining means and said firebox, such entraining means being also arranged to eject the entrained particles of fuel through said passage into the firebox out of the zone of action of said distributing means, and a motor for simultaneously operating said fuel conveying means and the fuel entraining and e ecting means.

11. In a locomotive having a firebox provided with a backwall, a firing opening in said backwall, a fire-arch extending upwardly and rearwardly from the lower forward end of said firebox and terminating short of said backwall forming between said fire-arch and said backwall an escape passage for products of combustion, means for delivering fuel to said firebox including means for separating particles of fine fuel from the coarse fuel, means providing a passage for the delivery of the separated particles of fine fuel from said separating means to said firebox, said passage opening into said firebox at a point beneath said fire-arch and remote from said escape passage and means for projecting the coarse fuel into said firebox through the firing opening in said backwall.

12. In a locomotive having a firebox provided with a grate and a backwall, a firing opening in said backwall, a fire-arch extending upwardly and rearwardly from the lower forward end of said firebox and terminating short of said backwall forming between said fire-arch and said backwall an escape passage for products of combustion, means for delivering fuel to said firebox including means for separating particles of fine fuel from the coarse fuel, means providing a passage for the delivery of the separated particles of fine fuel from said separating means to said firebox, said passage opening into said firebox at a point between said fire-arch and said grate and remote from said escape passage and means for projecting the coarse fuel into said firebox through the firing opening in said backwall.

13. In a locomotive having a firebox provided with a backwall, means for delivering fuel to said firebox having a discharge and adjacent said backwall, a fire-arch extending upwardly and rearwardly from the lower forward end of said firebox and terminating short of said backwall forming between said fire-arch and said backwall an escape passage for products of combustion, said fuel delivering means including means for separating particles of fine fuel from the coarse fuel, means providing a passage for the delivery of the separated particles of fine fuel from said separating means to said firebox, said passage opening into said firebox at a point beneath said firearch and remote from said escape passage and means adjacent said backwall for projecting the coarse fuel over the firebed in said firebox.

PAUL A. KETCHPEL.

CERTIFICATE OF sme ma Patent No. 2,044,508. June 16, 1936.

PAUL A. KETCHPEL.

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 1, first column, line 32, for "in" read into; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 29th day of September, A. D. 1936.

Henry Van Arsdale (Seal) Acting Commissioner of Patents.

Images