US2237428A - Stoker - Google Patents

Description

W. T. HANNA April 8, 1941. V

STQKER Original Filed May 11, 1937 s 2 a m m E000 Wm l. A m m. m

Patented Apr. 8, 1941 STOKER William Thompson Hanna, Cincinnati, Ohio Refiled for abandoned application Serial No.

141,894, May 11, 1937. This application November 17, 1939, Serial No. 304,917

1 Claim.

This invention relates to stokers in general and particularly to stokers of the type used upon locomotives.

One of the objects of this invention is to provide a conveyor system which is simple and durable in construction, and yet is efllcient in operation. Another object is to provide an apparatus for moving a material such as coal from a stor-' age place to a fuel chamber in a thoroughly practical manner. in part obvious and in part pointed out below.

This is a refiled application based on my application Serial No. 141,894, filed May 11, 1937, and abandoned September 22, 1939.

In the drawing:

Figure 1 is a side elevation of one embodiment of this invention, with portions cut away so as to show certain details;

Figure 2 is an enlarged horizontal section of a portion of the structure shown in Figure 1; and

Figure 3 is a modified form of a conveyorsupport-ing thrust-bearing.

In this particular embodiment, means is provided to move fuel from a bin on the locomotive tender through suitable conduits to the locomotive fire box. Referring to the right of Figure 1, fuel is fed by gravity through an opening in the floor of fuel bin 30 to tender hopper 23; it is then moved to the left in tender hopper 29 by a. screw conveyor 31, past a crusher (Figure 2) 32; after passing crusher 32, it falls through delivery port 28 and is received in the lower end of transfer conduit 22; a screw conveyor 25 in transfer conduit 22 then moves the fuel to the left to an extension conduit 2| (Figure 1) from which his moved by a pair of conveyors (not shown) into a fuel supply housing l1; it then passes through firing opening 16, in the back head of the fire box 14 onto distributing plate from which it is propelled by jets of steam, from blast chamber i9, and is distributed over the fire bed.

The floor of fuel bin 30 is here arranged in the form of a series of sliding plates which may be shifted to admit fuel at any place along the top of tender hopper 29. The conveyor 31 comprises a tapered hub 33 having a spiral vane 34 thereon which extends from the rear end (to the right of Figure l) to the edge of delivery port 23 (Figure 2). To facilitate the movement of the fuel downwardly through delivery port 28 to transfer conduit 22, the hub 33 is provided with an auxiliary spiral vane 35, preferably winding about hub 33 in theopposite direction to that of vane 34.

In the present embodiment, conveyor 3| is sup- These and other objects will be ported at its ends in self-aligning bearings 36 and 31 (Figure 1) which are mounted in the front and rear walls, .38 and 33, respectively, of tender hopper 29. Bearing 31 is provided with a cap 49 which has a collar portion extending through a recess in rear wall 39 and is rigidly attached thereto. Mounted within this collar portion and held in place by retaining ring 42 is a self-aligning ring bearing 4|. Ring bearing 41 is in the form of a section of a sphere and is snugly journailed in a correspondingly shaped recess in cap 40 and retaining ring 42. Hub 33 of conveyor 3| is reduced in diameter at its rear end to form a stud shaft which is received in the center of ring bearing 4!.

Referring to Figure 2, bearing 36 is of the ball type and provides an antifriction support for conveyor 3i and at the same time, resists end thrust in either direction. Bearing 36 is provided with an outer ring 43 which is preferably in the form of a, section of a. sphere and is tightly journalled in a correspondingly shaped recess formed in end wall 38 and retaining ring H. The inner ring of ball bearing unit 36 is snugly received upon the reduced forward end of hub 33 between a shoulder 1-35 and gear 15.

The rear end of transfer conduit 22 is secured in a T-conneotion 2B which has an upward extension 21. Extension 21 is shaped in the form of a section of a sphere and is journa-lled in the correspondingly shaped lower end of delivery port 28. T-connection 26 provides reenforcing and supporting means for transfer conduit 22. Transfer conduit 22 is also provided with an end wall I22 through which the reduced end of transfer conveyor 25 extends. In order that access may be had to conveyor 31 and delivery port 28, a removable plate 52 (Figure 2) is mounted at the top of the tender hopper 29.

Power for the operation of the stoker may be supplied by any suitable power device and transmitted to the moving elements in any convenient manner. However, I prefer to use a steam motor as the source of power and so to arrange the transmission mechanism that all such moving elements will be driven from a central point.

Referring to Figure 1, a steam motor of suitable type is mounted on the locomotive and this motor has a revolving crank shaft 51 extending rearwardly therefrom. Power is transmitted from this crank shaft to the various moving elements in the following manner: to the projecting rear end of crank shaft BI is universally connected the forward end of a telescoping shaft 82, which has its opposite end similarly connected to a short shaft 83. iournalled in a bracket 64, formed on or connected to, the T-connection 26. On this shaft 63 is fixed a gear 65 which serves as the central point from which the power may be distributed throughout the stoker. Powerto the conveyor 25 is transmitted by means of a gear 68 (Figure 2) meshing with the gear 65 (Figure '1) and fixed upon the conveyor shaft. Similarly, power is transmitted to the conveyor 3! through the medium of a gear 61 (Figure 2) on this shaft which meshes with a gear 68 (Figure 1) on a shaft 89 which is iournalled in an extension Ill of the bracket 64. The shaft 69 is operativeiy connected to a shaft H journalled in bracket 12 on the tender hopper 28, the driving connection being in the form of a telescoping shaft 13 universally connected at its ends to the shafts 69 and H. Rigidly secured upon the shaft H is a gear H in mesh with a gear 15 (Figure 2) secured to the forward end of the conveyor 3|.

Additional gear means, shown in Figure l, transmits power from gear 65 to the various other movable elements of the stoker.

As shown in Figure 1, the steam motor 60 is controlled by a suitable control valve operated by a lever 95, by means of which the speed, the direction of motion, and the effective power del'iveredmay be regulated.

This arrangement of the power transmission mechanism gives greater efficiency in the consumption of power and more latitude in the location of the power unit. The power device may be located in any convenient position and the power transmitted to the central distributing point by any suitable connection.

The annular bearing supports for the tender hopper conveyor 3|, with the self-aligning features, insure freedom of operation of this conveyor and facilitate repair and replacement.

The auxiliary vane or worm 35 on the tender hopper conveyor shaft, winding in the opposite direction with respect to the main worm or vane on this shaft, very materially assists in the delivery of the fuel to the conveyor 25. This is done by deflecting the fuel from its path of movement toward the left, and, at the same time, tending to move fuel from end wall 38 to the right. Thus, if there is any tendency of the fuel to clog or jam, vane 35 counteracts such a tendency.

A.modifled form of antifriction thrust bearing, of the type of ball bearing unit 36, is shown in Figure 3. This embodiment is a tapered roller bearing unit, having inner rings 45 and 4'6, tapered rollers 41 and 48, and outer ring 49. Inner rings 45 and 46 are rigidly held on the reduced end portion of hub 33 between shoulder I38 and gear 'l5, and carry tapered rollers 41 and I8, respectively. Outer ring 49 is rigidly secured to front wall 38 of the tender hopper 29 by means of suitable screws. If desired, this bearing may be made self-aligning by mounting outer ring 49 in a spherical recess in the same manner that roller bearing 36 is mounted.

This arrangement of conveying mechanism offers the minimum of obstruction to the free passage of the fuel from the fuel bin on the tender to the firing opening on the locomotive. Furthermore, it accomplishes the transfer of the fuel from the tender hopper through the fuel handling and conditioning means in a substantially direct path and thus reduces the natural tendency of the fuel to pack. During this movement, the fuel is moved past crusher 32, where any necessary crush-ing is performed, without danger of stoppage of the fuel movement.

As many other embodiments may be made of the features of this invention without departing from the scope thereof, it is to be understood that all matter herein set forth or shown, is to be interpreted as illustrative and not in a limiting sense.

I claim:

In a locomotive stoker for crushing coal and for transferring the crushed coal from a tender to the firebox of a locomotive, in combination, a hopper located beneath the coal bin of the tender and at its forward end having a downwardly opening delivery opening, a rotary screw conveyor in said hopper to move fuel forwardly therein to said delivery opening, said screw conveyor comprising a helical vane on a hub and said vane terminating adjacent the rear edge of said delivery opening, a stationary crushing member disposed in said hopper in cooperative crushing relation with said screw conveyor and rearward of said delivery opening and with its forward terminus coinciding substantially with that of said screw conveyor to crush coal being moved by said screw, and a second rotatable helical vane on said hub pitched in reverse direction to that of said first mentioned vane and extending substantially across said delivery opening, said second vane serving to loosen the coal after crushing and to sweep it freely into the delivery opening in a loosened condition whereby flow of coal past the crusher is not retarded by congestion in the vicinity of the delivery opening.

WILLIAM THOMPSON HANNA.

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