US2270883A - Locomotive stoker - Google Patents

Description

Jan. 27, 1942. N. M. LOWER LOCOMOTIVE STOKER Filed 001;. 29', 1938 2 Sheets-Sheet 1 Jan. 27, 1942. N; M. LOWER LOCOMOTIVE STOKER Filed Oct. 29, 1938 2 Sheets-Sheet 2 mvsN'roR Nathan M. Lower BY IWf/ ATTORNEYS- Patented Jan. 27, 1942 LOCOMOTIVE 'STOKER Nathan M. Lower, Erie, Pa., assignor to The Standard Stoker Comp poration of Delaware any, Incorporated, a cor- Application October 29, 1988, Serial No. 237,652

6 Claims.

This invention relates to stokers of the type which feed fuel into the furnace through an opening in an upright wall of the furnace. More particularly, the invention relates to locomotive stokers embodying a pressure fluid blast for propelling fuel upwardly and forwardly against a plate member positioned in the firing opening for subsequent distribution over the firebox grates.

In the application of stokers to locomotives of existing types, it has often been found that the lower edge of the firing opening of the backwall is in such relation with the firebox grates that the use of the ordinary distributing mechanism is not practical because it would be positioned at or an insufficient distance above the normal level of the firebed. Accordingly, it has been proposed to dispense with the usual distributing table from which fuel is projected forwardly by the pressure fluid blast, and providing instead a plate member which overhangs the pressure fluid blast issuing head at a substantial height above the firebed. In such structures, the pressure fluid head has been provided with a plurality of jet openings which are drilled so as to issue pressure fluid blasts against the underside of the overhanging plate member. The face of the pressure fluid head in which the jet apertures are drilled has heretofore been arranged to slope forwardly and downwardly toward the firebox.

In such constructions, the fuel is delivered to the jet face in two ways, namely: by being pushed from the bottom of the mass of moving coal over the top edge of the pressure fluid head along its downwardly sloping face; or by rolling down the incline formed by the angle of repose of fuel. Since the front face of the pressure fluid head, in prior constructions, is sloped downwardly from the horizontal, fuel attains an appreciable velocity in a downward direction by the time it reaches the zone of action of the pressure fluid blasts. With this construction, the path in which fuel will travel from the pressure fluid head into the firebox is a resultant of its downward velocity and the forward and upward velocity exerted by the pressure fluid jets.

Because of this condition, stokers of this general type have not been successful from a practical point of view because a preponderant amount of fuel drops unchecked through the pressure fluid blasts, because of its velocity in a downward direction, and results in extremely heavy fires along the rear central portion of the firebox. Accordingly, it is the principal object of this invention to improve generally distribution of fuel in stokers of the type which employ to an overhead plate member against the underside of which fuel is forcibly impinged.

Another object of the invention is to provide a construction and arrangement of parts in a stoker of the type described whereby fuel is evenly distributed over all parts of the fire in the firebox with the application of less force in projecting the fuel than has heretofore been possible.

More specifically, an object of the invention is to provide a novel, practical and efficient fluid pressure distributing head of a stoker for the projection of fuel into a firebox.

Other objects and advantages of the invention will become apparent from the following description and the appended claims when taken in connection with the accompanying drawings, in which Fig. l is a central vertical longitudinal sectional view through the rear part of a locomotive showing the improved stoker partly in similar section and partly in elevation;

Fig. 2 is a sectional View taken on the line 2-2 of Fig. 1, looking at the stoker from within the firebox through the firing opening;

Fig. 3 is a sectional plan view taken on the irregular line 3-3 of Fig. 1; and

Fig. 4 is a sectional View taken on the irregular line 44 of Fig. 1.

Referring to these drawings, which illustrate the invention as applied to a locomotive .A, a boiler isshown at I0 provided with a backhead I I rearward of the firebox l2. The bottom of the firebox is formed by grates 13 which support the firebed. A firing opening M is formed in the backhead l I above the cab deck I 5 and also above the level of grates l3. In the present instance, the lower marginal edge of the firing opening is a relatively short distance above the grates It.

A stoker S delivers coal to the firebox l2 and comprises a conduit I6 communicating with the firebox through the firing opening M. The conduit I6 is surmounted by a casing I! having an aperture l8 in its rear edge opposite the firing. opening M. A door I9 is supported upon said casing l7 and forms a movable closure for the aperture l8. Fuel is conveyed forwardly and upwardly toward the firing opening M by a conveyor screw 20 disposed within the conduit It. At its lower end the screw 20 is flexibly connected at 2| to a screw 22 which is housed within a conduit 23 leading forwardly from the tender (not shown). The conduits l6 and 23 are connected by a ball and socket joint 24 which provides for the necessary flexibility between the conduits when the locomotive is in operation.

Fuel is conveyed by the conveyor screw into the zone of action of a pressure fluid head 25 which is positioned at the lower portion of the firing opening and projects fuel toward the firebox.

Since the lower marginal edge of the firing opening I4 is but a short distance above the grates l3, it is preferable to arrange the distributor head 25 so that it issues blasts of pressure fluid for projecting fuel against the underside 26' of a deflector plate 21 which extends into a firing opening I4 and forwardly into the firebox I2. At its rearward end, the deflector plate 21 is secured by bolts 29 to a shaft 30 within the casing l1 and is arranged for vertical adjustment about the axis of the shaft 39. The deflector plate 21 at each lateral side thereof is provided with an outwardly curved wall 3! which serves to intercept fuel projected upwardly by the head 25, as will presently appear. The lower portion of the casing 11 is recessed in its bottom as indicated at 35, the recess extending between the side walls 36,. 31 of the casing l1. Within the recess 35 is fitted the pressure fluid head 25, the upper wall it of which constitutes the bottom wall of the lower portion 9 of casing 11. For the purpose of securing the pressure fluid head 25 upon seats 39, All formed in respective side walls 36, 31, a set screw 1 is threaded into each side wall for engaging lugs 8 formed on the rearward portion of the pressure fluid head 25.

Internally, the pressure fluid head 25 is divided into a plurality of chambers M, of which there are three in the presnt embodimnt of the invention although any desired number could be provided. This pressure fluid is supplied to the chambers 4| by means o supply lines it. The upper wall 38 of the pressure fluid head 25 is fiat in transverse cross section and extends forwardly and upwardly substantially parallel to the axis of conveyer screw 22, terminating at its upper end adjacent the outer surface of the backhead II and lying above the lower margin of the opening it. From this point the upper wall turns inwardly so that its upper face A5 is horizontally disposed within the firing opening 14. This horizontal face extends across substantially the width of the lower portion of the firing opening l4 and between the forward extensons 36a, 31a. of the respective side walls 38, 31 of the casing l1. The face 45 of the pressure fluid head 25 is drilled to provide a series of apertures 46 which are directed upwardly at an angle approximately 45 with the horizontal so as to direct blasts of pressure fluid against the underside 26 of the deflector plate 21. Proferably apertures 46 are arranged in a pair of rows extending transversely of the firebox and the forward and rearward rows are so arranged that the jetapertures are in a staggered relation considered longitudinally of the locomotive.

This results in more efficient handling of the fuel by the pressure fluid blasts as will hereinafter be more fully explained.

In the operation of this device, fuel is conveyed by the screw 22 through the conduit 16 and along the upper wall 38 of the pressure fluid head 25. As the fuel is elevated within the casing l1 it assumes an angle of repose of approximately 45 with the horizontal, the lower edge of which is at the upper terminal end of wall 38. It will be observed that with the fuel elevated to this position, the face 45 of the pressure fluid head is approximately horizontal and the fuel,

upon being urged forwardly and upwardly by the screw 22, will be moved over the face 45 and into the zone of action of the pressure fluid head. Fuel which rolls down the incline formed by its angle of repose will have its velocity reduced upon reaching the horizontal fuel supporting face 45 so that the major force acting on the fuel will be the upward and forward propelling action developed by pressure fluid issuing from the head 25. Thus with the face 45 constructed to impede the rapid descent of fuel and afford a support therefor, the resultant path of the fuel toward the deflector 26 will be determined practically by the jets alone. Furthermore, with this construction, the fuel moves into the zone of action of the pressure fluid jets at a more moderate rate so that a greater time element will be present for the jets to act upon the fuel and forcibly impinge it against the underside 25 of the deflector 21. In order that control over distribution may be attained and also for the purpose of gaining access to the interior of the firebox 12, the deflector member 21 may be swung about the axis of shaft 30 by a handle 48 which is secured to the shaft to in any suitable manner. The deflector 21 may then be locked in any position of adjustment by means of a pin 49 passing through a hole 50 in the handle 58 and any one of a number of holes 52 in a lock 53 formed along one side of the casing 11.

The forwardly and outwardly curved walls 31, referred to above, are laterally spaced and depend from the deflector plate 21. These walls 3! serve to intercept a portion of the fuel projected by the fluid under pressure issuing from the jet apertures 46 and direct it to the rear corners of the firebox.

I claim:

1. In a firebox having an upstanding wall provided with a firing opening, a stoker comprising a fuel feed conduit communicating with said opening and means at the delivery end of said conduit for distributing the fuel delivered from said fuel feed conduit over the fire in said firebox, said distributing means including a hollow pressure fluid head, the top wall of said head being so formed and disposed to normally retain on its upper sur-.

face against movement thereacross by gravity substantially all the fuel delivered thereto from said fuel feed conduit, said top wall being pro vided with a plurality of jet apertures for the emission of fluid under pressure for projecting the fuel from said top wall in an upward direction.

2. In a firebox having an upstanding wall provided with a firing opening, a stoker comprising a fuel feed conduit communicating with said opening and means at the delivery end of said conduit for distributing the fuel delivered from said fuel feed conduit over the fire in said firebox, said distributing means including a hollow pressure fluid head, the top wall of said head being substantially horizontally disposed and formed to support fuel delivered thereto from said fuel feed conduit against downward movement, said top wall being provided with a plurality of jet apertures for the emission of fluid under pressure for projecting the fuel from said top wall in an upward direction.

3. In a firebox having an upstanding wall provided with a firing opening, a stoker comprising a fuel feed conduit communicating with said opening and means for distributing the fuel delivered from said fuel feed conduit over the fire in said firebox, said distributing means including a hollow pressure fluid head extending substantially the width of said opening within the lower portion thereof and having a top wall so formed and disposed to normally retain on its upper surface against movement thereacross by gravity substantially all the fuel delivered thereto from said fuel feed conduit, said top wall being provided with a plurality of jet apertures for the emission of fluid under pressure for projecting the fuel from said top wall in an upward and forward direction.

4. In a firebox having an upstanding Wall provided with a firing opening, a stoker comprising a fuel feed conduit communicating with said opening and means for distributing the fuel delivered from said fuel feed conduit over the fire in said firebox, said distributing means including a pressure fluid head having a fuel supporting surface at said firing opening so formed and disposed to normally retain thereon against movement thereacross by gravity substantially all the fuel delivered thereto from said fuel feed conduit, and a fuel deflecting member spaced above and extending forward of said pressure fluid head, the fuel supporting surface of said head having a plurality of jet apertures for the emission of fluid under pressure for projecting the fuel in an upward direction toward the under side of said deflecting member, said deflecting member having outwardly curved depending ribs arranged to intercept a portion of the projected fuel for deflecting it laterally.

5. In a firebox having an upstanding wall provided with a firing opening, a stoker comprising a fuel feed conduit communicating with said opening and means for distributing the fuel delivered from said fuel feed conduit over the fire in said firebox, said distributing means including a pressure fluid head having a substantially horizontal surface at said firing opening for supporting fuel against downward movement and a fuel deflecting member spaced above and extending forward of said pressure fluid head, the fuel supporting surface of said head having a plurality of jet apertures for the emission of fluid under pressure for projecting the fuel in an upward direction toward the under side of said deflecting member, said deflecting member having outwardly curved depending ribs arranged to intercept a portion of the projected fuel for deflecting it laterally.

6. In a firebox having an upstanding wall provided with a firing opening, a stoker comprising a fuel feed conduit communicating with said opening and means for distributing the fuel delivered from said fuel feed conduit over the flre in said firebox, said distributing means including a pressure fluid head extending substantially the width of said opening within the lower portion thereof and having a fuel supporting surface so formed and disposed to normally retain thereon against movement thereacross by gravity substantially all the fuel delivered thereto from said fuel feed conduit, and a deflecting member spaced above said pressure fluid head and extending through said firing opening forward of said head, the fuel supporting surface of said head having a plurality of jet apertures for the emission of fluid under pressure for projecting the fuel in an upward direction toward the under side of said deflecting member, said deflecting member having outwardly curved depending ribs arranged to intercept a portion of the projected fuel for deflecting it laterally.

NATHAN M. LOWER.

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