US2137844A - Blast feed stoker - Google Patents

Description

Nov. 22, 1938.

P. A. KETCHPEL BLAST FEED STOKER Original Filed April 22, 1933 3 Sheets-Sheet 1 INVENTOR.

ATTORNEY.

Nov. 22, 1938. P. A. KETCHPEL BLAST FEED STOKER Original Filed April 22, 1933 5 Sheets-Sheet 2 V ZNVENTOR. Paub Affefchpet ATTORNEY.

Nov. 22, 1938. p, KETCHPEL 2,137,844

BLAST FEED STOKER Original Filed April 22, 1933 5 Sheets-Sheet 5 E5? 65 6,2 J4 INVENTOR. jg 'Puid/ A. Kebc hp 91/ ATTORNEY.

PATENT OFFICE,

BLAST FEED STOKEB Paul A. Ketchpel, West Englewood, N. J., alsignor, by mesne assignments, to The Standard Stoker Company, Inc., (1922), a corporation of Delaware Application April 22, 1933, Serial No. 887,356

Renewed April 20, 1938 Claims. (Cl. 110-104) My invention which relates to blast feed stokers for locomotive or similar boilers has for its principal object the provision of a stoker of the type specified wherein a pressure fluid blast propels the 5 fuel through a delivery conduit in communication fuel receiving portion, a horizontal fuel discharge a portion above the plane of said receiving portion and in advance thereof, and a feed section connecting said portions, the fuel discharge conduit being of a shape and configuration such that the fuel is passed therethrough without any undue friction which would otherwise reduce its velocity.

A still further object of the present invention resides in the provision of a blast feed stoker for locomotives in which a trough is mounted rigidlyon the tender beneath the fuel bin, the fuel discharge conduit is mounted on the locomotive and an intermediate conduit section isdisposed between the trough and the discharge conduit, the intermediate section, comprising a plurality of flexibly jointed elements which afford lateral and vertical displacement of the intermediate section, the longitudinal movement between the locomotive and tender being compensated by telescoping the rearward end of the intermediate section wit the forward end of said trough.

Another object of this invention consists in the method and means of introducing cinders and other partly consumed products of combustion into the stream of coal as it is propelled through the stoker whereby the partly consumed cinders, while in a hot state, are thoroughly mixed with the coal and thus projected into the firebox and upon the grate thereof, which has the effect of promoting combustion.

More specific objects and advantages will be apparent as the description of the invention is read in connection with the accompanying drawings, in which Figure 1 is a central vertical longitudinal section of the improved blast feed stoker, showing its the irregular line Figure 9 is a transverse section taken on the line 9-8 of Figure 1;

Figure is a view partly in elevation and partly in section showing a modified form of the invention illustrated in Figure 1;

Figure 11 is a central vertical longitudinal section of the locomotive tender showing a portion of the stoker illustrated in" Figure 10 in section; and

Figure 12 is a detailed longitudinal section of the front end of the locomotive, showing the smokebox and a portion of the cinder return tube.

In Figures 1 to 9 inclusive, which illustrate one.

form of this invention, the locomotive A is providedwith a firebox l0 having a rear wall I I which is provided with a firing opening l2 disposed above the grates 9. The tender B is connected to the locomotive A by a coupler C and includes the floor l3 above which is disposed a coal bin I4. The floor I3 is apertured as at l5 and slidable plates I6 cover this aperture entirely or they may be moved to partially uncover the aperture so that coal may drop into the trough l'l. This trough or transfer conduit preferably, is rigidly mounted beneath the floor l3 and houses a conveyor screw l8 which urges the fuel forwardly toward the firebox for propulsion thereinto as will presently appear. The motive power for operatingvthe conveyor screw it is generated by a prime mover such as I! and is transmitted to the conveyor screw by the gearing 20 at the rear of the trough II.

The forward end of the trough ll terminates in a tubular extension 2| and the conveyor screw l8 may protrude into this extension for a short distance. "A pressure fluid head 22 is positioned in the tubular extension 2| immediately forward of the conveyor screw l8 and discharges a relatively powerful fan-shaped blast of pressure fluid for propelling coal forwardly into the firebox through the intermediate conduit 23 and the discharge conduit 24.

This discharge conduit 24 consists of a forwardly directed approximately horizontal portion 25 which passes through the lower portion of the firing opening [2, a downwardly and rearwardly extending section 26 which terminates at a point below the cab deck 21 in a rearwardly and horizontally extending fuel receiving portion 28. Secured in any suitable manner to this portion 28, as by the bolts 29, is an end. member 30 of the intermediate conduit 23. A plurality of such members are utilized to form the intermediate conduit and they are joined together by pintles such as 3| and have their coacting surfaces of a form which permits relative angular movement between them. At its end remote from the discharge conduit 24, the intermediate conduit 23 is secured to a sleeve 32 which fits freely over the tubular extension 2i and telescopes thereover when the locomotive and tender are negotiating curves. If desired, a. bar such as 33 may be used to prevent sagging of the intermediate conduit 23. This bar is loosely attached between the discharge conduit 24 and the sleeve 32 in a manner which will permit a slight angular displacement of the intermediate conduit 23 when the locomotive and tender are passing over switches, frogs or turntables.

The discharge conduit 24 is of novel construction and permits coal to be passed therethrough in an eificient manner. At its rearmost end, the horizontal portion 28 of the discharge conduit is circular in cross section in order to receive the end member 30 of the intermediate conduit 23.

. It is desirable that the coal be discharged from the conduit 24 in a fiat sheet of uniform cross sectional area throughout, and hence, as the discharge conduit 24 extends upwardly and forwardly toward the firing opening l2, its cross sectional configuration varies as will presently appear.

From its circular rearward end, the conduit 24 expands laterally into a section as illustrated in Figure 8, having a substantially fiat bottom, and arcuate sides and top, from which the cross sectional configuration of the conduit changes to that illustrated in Figure 7, having the flat bottom wall 35, the vertical sides 36, 31 and the arcuate roof 36. As the conduit 24 continues upwardly its cross sectional shape changes in a manner as illustrated by Figures 5 and 6, wherein the roof 38 is flat and the bottom wall 35 is arcuate and curves away from the normal path of the coal passing through the conduit so that frictional resistance may be reduced to a minimum.

By the particular construction of the discharge conduit 24, the fuel, as it is propelled through the conduit, passes along the flat bottom wall 35 at the lower end of the conduit and then the direction of the fuel is changed so that it passes along the flat roof 38 at the upper end of the conduit. Since the lower portion of the flat bottom wall 35 and the upper portion of the flat roof 36 are formed by arcs of relatively large circles, the

velocity of the fuel in its passages through the discharge conduit is not diminished by tortuous bends and curves. Propelling the fuel along the flat walls 35 and 38 permits the fuel to be discharged in a thin, wide sheet which insures even delivery of fuel to the firebed on the grates 9.

The forwardly directed portion 25 of the discharge conduit 24 is preferably in the form of a separate casting which is secured to the discharge conduit 24 by the bolts 39 passing through lugs such as 390.. Its transverse cross sectional shape conforms substantially to the upper portion of the discharge conduit as shown in Figures 5 and 6.

, At its upper forward end, the forwardly directed portion 25 is provided at each side with a laterally curved fuel deflecting channel such as 40 for diverting a portion of the fuel to the sides of the firebed. A plate 4| is disposed beneath the upper wall of the portion 25 and is provided with abutments such as 42 which stop the forward advance of a portion of the fuel stream and deflect it to the rear corners of the firebed. Preferably, the vertical height of the forwardly directed portion 25 is slightly greater than the thickness of the fuel stream.

In the form of the invention illustrated in Figures 10 to 12 inclusive, the discharge conduit 24 and the trough I! are connected by an intermediate conduit 45 which consists of a flexible tube 46 and a sleeve member 41 telescopically .mounted on the tubular extension 2| of the trough. IT. A pressure fluid head 48 is secured within the sleeve member 41 and as the conveyor screw i8 drops the coal into the sleeve member 41, .the coal is propelled through the intermediate conduit 45, the discharge conduit 24 and hence, into the firebox A flexible hose 49 supplies steam or compressed air to the pressure fluid head 48.

When burning coal in furnaces, and especially in locomotive fireboxes, approximately twenty per cent (20%) of the coal is unconsumed, the greater portion of this unconsumed coal being in the form of cinders. It is an object of this invention to re-introduce such unconsumed fuel particles into the stoker conduit, there to be mixed with the fuel which is being propelled toward the furnace; this is accomplished by a novel relation which is now to be described.

In locomotives, the products of combustion pass from the firebox through the lines 50 and into the smokebox 5| at the front end of the locomotive. The smokebox 5| is supported on the cylinder saddle casting 52 in the customary manner and is divided into the compartments 53 and 54 by a diaphragm or wall that comprises a rear imperforate portion 55, and a foraminous portion or screen 56. The compartment 54 communicates directly with the lines 50, and the compartment 53 communicates directly with the inside stack or petticoat pipe 51 and the smoke stack 58, through which the waste gases of combustion are discharged to the atmosphere. The waste gases of combustion carry a relatively large amount of cinders and unconsumed fuel particles which pass through the fiues 50 into the compartment 54. Fine particles of unconsumed fuel pass through the foraminous portion 56 while the larger particles drop from the screen onto a chute or wall 59 which extends downwardly and are deposited in the lower portion thereof. The cinders are thus deposited into a trough-like structure 60, of which there may be two, one at each side of the exhaust nozzle 6|.

These. solid particles of fuel are discharged from the smokebox by a pressure fluid blast issuing from the jet head62, disposed within each trough 60. If desired, a blower fan may be utilized to generate swiftly'moving currents of preheated air for returning the hot cinders to the fuel steam, and the same or a similar fan may be used to propel the coal into the firebox. To prevent the dissipation ofthe pressure fluid blast through the smokebox, a hood 63 is provided over each trough and as the cinders drop into the zone of action of the jet head 62, they are blown rearwardly through tubes such as 64 to a point adjacent the intermediate conduit 45. At this point, the tubes 64 are each provided with the 'return bend 65 which reverses the direction of flow of the cinders and causes them to be delivered into the intermediate conduit 45 immediately ahead of the jet head 48. Thus, the hot cinders are introduced into the path of the coal as it passes through the stoker conduits and in this manner an intimate mixture of coal and hot cinders is spread over the grates 9. This assures the positive delivery of the cinders onto the firebed and the presence of the hot cinders in the coal stream has the effect of heating the coal to a point such that its ignition in the firebox is accelerated.

From the foregoing, it will be apparent that of my invention may be made within the scope of the following claims.

I claim:

1. In combination with a firebox having a grate and a firing opening in one of its walls above said grate, a source of fuel supply, a fuel conduit extending from such source to said firing opening, said conduit including a discharge section in communication with said firing opening, pressure fluid blast emitting means in said conduit located to discharge a blast of fluid under pressure so directed as to propel the fuel through said conduit and onto the grate and means for conveying fuel from the source of supply to said pressure fluid blast emitting means, said pressure fluid blast emitting means constituting the sole means for projecting the fuel onto the grate, said discharge section having its opposite ends offsetwith respect to each other and opening in opposed directions, the receiving end portion of said discharge section being formed as a curved elbow and the discharge end of said discharge section being formed as a curved elbow, the outer portion of the curve of each of said elbows being straight in transverse section. said elbows being so arranged that the tangent to the outer portion of the curve of said first named elbow at its forward end intersects the outer portion of the curve of said second named elbow.

2. In combination with a firebox having a grate and a firing opening in one of its walls above said grate, a source of fuel supply, a fuel iduit extending from such source to said firing opening, said conduit including a discharge section in communication with said firing opening, pressure fluid blast emitting means in said conduit located to discharge a blast of fluid under pres sure so directed as to propel the fuel through said conduit and onto the grate and means for conveying fuel from the source of supply to said pressure fluid blast emitting means, said pressure fluid blast emitting means constituting the sole means for projecting the fuel onto the grate, said discharge section having its opposite ends offset with respect to each other and opening in opposed directions, the receiving end portion of said discharge section being formed as a curved elbow and'the discharge end of said discharge section being formed as a curved elbow, the outer portion of the curve of each of said elbows being straight in transverse section, said elbows being so arranged that the tangent to the outer portion of the curve of said first named elbow at its forward end intersects the outer portion of the curve of said second named elbow, a fuel deflector within the firebox at the forward end of the roof of said second named elbow and an abutment member beneath said deflector, said abutment member extending transversely of the direction of projection of the fuel within the lower stratum of projected fuel.

3. In combination with a locomotive and its tender, the former having a firebox provided with a backwall having a firing opening therein above the firebox grate and the latter having a fuel bin disposed above the tender deck, a fuel conduit extending from the tender to the locomotive and communicating with the firebox through said firing opening, said conduit including a trough rigidly disposed beneath said bin and receiving fuel therefrom, a discharge section on said locomotive arranged to discharge fuel into the fire-- box through said firingopening, and a flexible section connecting said trough and said discharge section, pressure fluid blast emitting means in said conduit located to discharge a blast of fluid under pressure so directed as to propel the fuel through said flexible section and said discharge section and onto the grates, and means for conveying fuel from said trough to said pressure fluid blast emitting means, said pressure fluid blast emitting means constituting the sole means for projecting the fuel onto the grate, said discharge section having its opposite ends offset with respect to each other and opening in opposed directions, the receiving end portion of said discharge section being formed as a curved elbow and the discharge end of said discharge section being formed as a curved elbow, the outer portion of the curve of each of said elbows being straight in transverse section, said elbows being so arranged that the tangent to the outer portion of the curve of said first named elbow at its forward end intersects the outer portion of the curve of said second named elbow.

4. In combination with a firebox having a firing opening in an upright wall thereof, a source of fuel supply, a fuel conduit extending from such source to said firing opening, said conduit including a discharge section in communication with said firing opening, means for generating a fluid stream in said conduit so directed as to propel the fuel through said conduit and said firing opening into the firebox and means for introducing fuel into the path of said fluid stream, said fluid stream generating means constituting the sole means for projecting the fuel into the firebox, said discharge section having its opposite ends offset with respect to each other and opening in opposed directions, the receiving end portion of said discharge section being formed as a curved elbow and the discharge end portion of said discharge section being formed as a curved elbow, the outer portion of the curve of the elbow at the discharge end of said discharge section being straight in transverse section, said elbows being so arranged that the tangent to the outer portion of the curve of said first-named elbow at its forward end intersects the outer portion of the curve of said secondnamed elbow.

'5. In combination with a firebox having a firing opening in an upright wall thereof, a source of fuel supply, a fuel conduit extending from such source to said firing opening, said conduit including a discharge section in communication with said firing opening, means for generating a fluid stream in said conduits so directed as to propel the fuel through said conduit and said firing opening into the firebox and means for introducing fuel into the path of said fluid stream, said fluid stream generating means constituting the sole means for projecting the fuel into the firebox, said discharge section having its opposite ends ofiset with respect to each other and opening in opposed directions, the receiving end portion of said discharge section being formed as a curved elbow and the discharge end portion of said discharge section being formed as a curved elbow, the outer portion of the curve of each of said elbows being straight in transverse section, said elbows being so arranged that the tangent to the outer portion of the curve of said first-named elbow at its forward end intersects the outer portion of the curve of said secondnamed elbow.

PAUL A. KETCHPEL,

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