US2119750A - Stoker mechanism - Google Patents

Description

0. MOELLER STOKER MECHANISM June 7, 1938..

Filed Feb. 7, 1935 INVENTQR etta Noel/Len ATTORNEY blast will function automatically immediately with the plate l8, which is provided with out- Patented June 7, 1 938 UNITED STATES PATENT OFFICE STOKER MECHANISM Otto Moeller, Brooklyn, N. Y., assignor, by mesne assignments, to The Standard Stoker Company, Inc., (1922), New York, N. Y., a corporation of Delaware Application February 7, 1935, Serial No. 5,394 4 Claims. (Cl. 110-177) This invention relates to locomotive stokers of the type in which fuel is placed manually at the firing opening of the firebox and within. the firedoor, there to be automatically projected and distributed uniformly over the firebed by a pressure fluid blast.

It is an object of the invention to provide in a stoker of the type described novel, compact, em cient and simple means for coordinating the movement of the firedoorand the action of the pressure fluid blast, whereby the pressure fluid of, distributes fuel .evenly over all parts of the grate.

The firedoor 2| is provided with a frame 22 suitably mounted on the boiler backwall l3 partly embracing the firedoor opening which is closed by a pair of door members 23 and 24, pivoted upon the pins and 26 to swing outwardly. A motor 21 for operating the door members 23 and 24 is supported from the upper portion of the frame 22 by the pins 25 and 26 through the depending flange 28. The motor 21 is operated in a manner well known in the art, as describedin detail in the patent to Rosenfelt, No. 1,171,463, granted- February 15, 1916, by pressure fluid admitted through the pipe 29, and controlled by a. suitable valve 30. The valve 30 is responsive to movement of the treadle 3| through suitable arms 32 and 33 controlling the supply of pressure fluid to the pipe 29 and motor 2'! from the supply line 34.

In stokers of the type described above, it has been customary to provide an arrangement whereby a blast of steam will issue across a distributor plate from a distributor head when the firedoor is opened and will automatically be interrupted as soon as the door closes. Such an arrangement has several disadvantages which may best be recognized when the operation is described. The fireman steps on the treadle, opening the firedoor, and places a scoop of fuel on upon the opening of the firedoor and whereby the I pressure fluid blast will continue to function for a predetermined period of time after the firedoor is closed.

Other objects and advantages of the invention will become apparent from the following description when read in' connection with the accompanying drawing, in which,

Figure 1 is a central longitudinal section through a portion of a locomotive with the invention shown in elevation and in place on the locomotive Figure 2 is a rear elevation of the stoking mechanism embodying the invention;

Figure 3 is a view similar to Figure 1 with portions of the mechanism embodying the invention broken away and shown in section; and

Figure 4 is a vertical section through the novel valve mechanism. p

The invention may be applied to various types of furnaces, but it is particularly applicable to locomotive furnaces, more specially to furnaces'of locomotives of the switcher type, and for convenience in describing the invention it has been so shown in the drawing and will be so described.

In the drawing, the locomotive is indicated generally by the numeral Ill and is provided with the usual firebox I l, the grates l2, the boiler backwall l3 and the conventional firing opening 14. The locomotive cab is shown at l5 and is provided with the deck I6 located a sufiicient distance below the lower marginal edge of the firing opening l4 to permit convenient manual firing.

The stoking mechanism is represented generally by the numeral l1 and comprises-a distributor plate 18 detachably mounted and extending forwardly through the firing opening I4 into'the firebox II. A nozzle [9 is positioned at the rear of the distributor plate 18 and is arranged to issue a blast of pressure fluid over the surface thereof. The nozzle I9 in conjunction thereby closing the door. The door is therefore only open momentarily after the fuel is placed on the distributor plate, and since the steam blast issues only while the door is open, it is obvious that the steam blast will not be in operation a sufficient length of time to project all the fuel from the distributor plate onto the firebed. As a result, the firebox does not receive a sufiicient charge of fuel and repeated delivery of fuel upon the distributor plate by the fireman is necessary. As an alternative the fireman after deliverying a charge of fuel to the distributor plate, might keep his foot on the treadle until all the fuel is projected from the distributor plate, but this would necessitate permitting the firedoor to remain open, which is an obvious disadvantage.

These disadvantages are eliminated by means of the herein described device whlchpermits all the fuel delivered on the distributor plate to be projected over the firebed by a pressure fluid blast with but a momentary opening of the firedoor.

In the present arrangement, pressure fluid is admitted to the distributor head or. nozzle l9 wardly curving depressions 20 on each side therethe distributor plate, then releases the treadle,

through pipes 35, any suitable number of which 50 v thereby opening the door members 23 and 24 may be used. A pressure fluid supply line comprising pipes 36 and 36a has the novel valve mechanism 31 interposedtherebetween for controlling the supply of pressure fluid and communicates with the pipes 35 delivering pressure fluid thereto.

The valve mechanism 31 includes a casing 38- having a pressure fluid inlet port 39 communicating with the pressure fluid supply pipe 36 and a pressure fluid outlet port 40 communicating with the pressure fluid supply pipe 36a. A valve member 4| comprising a stem 42 carrying a. piston head 43 at one end'and a piston head 44 at.the other end, is arranged to reciprocate in the casing 38. The casing 38 is provided with a removable head 45 permitting access to the interior thereof and any suitable means may be employed for securing the head 45 rigidly with the casing 38.

,In one extreme position of its movement, as shown in Figure 4, the valve member 4| interrupts communication between the ports 39 and 49, cutting off the supply of pressure fluid to the pipes 35 and nozzle l9; while in its opposite position, the valve member 4| permits communication between the ports 39 and 40 allowing pressure fluid to, pass from the pipe 36 to the pipe 36a and thence to the pipes 35 and nozzle l9.

The end wall 46 of the casing 38 is provided with a large port "41 which is flared to form a seat 48 in the end wall 46. A valve member 49 having a .stem 50 arranged to slide in a bracket 5|, moves inwardly to its seat 48 to close the port 41 and away from its seat 48 to open the port 41. The valve member 49 and stem 50 are responsive to movement of the lever 52 which is pivoted at 53. One end of the lever arm 54 contacts the stem 59 and one end of the lever arm 55 contacts the lug 56 depending from the lower marginal edge of the door member 23.

A spring 51 mounted in the head 45 urges the valve member 4| towards the end wall 46 of the casing 38. The piston head 44 of the valve member 4| is provided with a. passage .56 which is.

considerably smaller in diameter than the port in the passage 58.

In operation, when the fireman steps on the treadle 3|, the valve. 30 is opened permitting pressure fluid to pass from the supply line 34 through the pipe 29 to operate the motor 21,

and breaking the contact between the lug 56 and the end of the lever arm 55. This permits pressure fluid in the chamber beneath the piston head 44, which holds the valve member 4| to the seat 6| against the pressure of the compressed spring 51, to unseat the valve 49 permitting the pressure fluid to exhaust to atmosphere through the port 41. The pressure'of the compressed spring 51 forces the valve member 4| towards the end'wall 46 until it rests on the seat 60, whereby the ports 39 and 40 are brought into communication. Pressure fluid passes from the supply pipe 36 into the supply pipe 36a, then to the pipes 35 and into the distributor head or nozzle |9 whence it projects the fuel delivered on the plate l8 into the firebox As soon as the fireman has delivered the fuel on the plate |8 he removes his foot from the treadle 3|, thereby causing the valve 30 to close,

cutting oif the pressure fluid supply, whereby raise the lever arm 54 about the pivot 53. The lever arm 54 forces the stem 50 upwardly causing the valve member 49 to engage the seat 48 thereby closing the port 41. Pressure fluid from the supply pipe 36 passes into the space between the piston heads 43 and 44 and then through the small passage 58 into the space beneath the piston head 44. The rate at which pressure fluid passes into the chamber beneath the piston head 44 may be regulated by a. needle valve 59 interposed in the passage 58. Thus, after the doors are closed, pressure fluid is still emitted from the nozzle I9 until the pressure in the chamber beneath the piston head 44 has been sufliciently built up to raise the valve member 4| against the pressure of the spring '51 until it rests against the seat 6|, thereby closing the port 40 and cutting off the supply of pressure fluid to the nozzle I9. e

When the door 2| is again opened to permit flring of fuel into the firing opening, contact between the lug 56 and lever arm 55 is again broken, permitting unseating of the valve member 49 whereby pressure fluid in the chamber beneath to force the valve member 4| toward the end wall 46 until it rests on the seat 60, thereby bringing the ports 39 and 40 into communication.

In operation, if it is found that the pressure fluid blast from the nozzle l9 shuts ofi too quickly after the flredoor is closed, it is only necessary to restrict the passage 58 by regulating the needle valve 59 whereby pressure fluid enters the chamber beneath the piston head 44 more slowly, permitting the ports 39 and 40 to remain in communication for a longer period of time; and conversely, if it is found that the pressure fluid blast continues too long after the firedoor is closed, it is only necessary to open the needle valve 59 a little wider, permitting pressure fluid in the rapidly, thereby-closing the port 49 sooner.

It is apparent from the foregoing that I have provided .a simple, convenient, eificient and compact mechanism for synchronizing the movement of, the" flredoor with the pressure fluid blast and for rendering the latter adjustable.

.lclaimz 1.: In combination with a furnace having a firing opening, a fuel supporting distributor plate in said flring opening, a fuel distributor head provided with jet openings directed across said plate for projecting fuel therefrom over the flre in said furna'ce, a door for the firing opening, a supply line for delivering fluid under pressure to said distributor head, a fluid operated valve interposed in said supply line controlling the flow of fluid to said distributor head, said valve comprising a casing provided with a fluid inlet port and a fluid outlet port, said ports communicating with said supply line, a valve element comprising spaced piston heads rigidly secured together mounted for reciprocation in said casing, adapted in one position to'establish communication between said inlet and outlet ports and in another position to close said outlet port, said casing being provided at one end with an exhaust port, a valve for opening and closing said exhaust port, means responsive to closing of said door for moving said valve to a position closing said exhaust port and responsive to opening of said door to permit movement of said valve to a position opening said' exhaust port, means at one end of said valve element for moving it to a position establishing substantially immediate communication between said inlet and outlet ports when said exhaust port supply line to said distributor head, a passage in said valve element discharging at the other end of said valve element adapted to permit fluid under pressure to pass therethrough to the said other end of the valve element for moving the valve element to a position closing said outlet port when said exhaust port is closed in response to the closing of said door, thereby interrupting passage of fluid under pressure through said supply line to said distributor head, the passage in said valve element being adapted to restrict the flow of fluid under pressure therethrough whereby movement of said valve element to close said outlet port is delayed an interval of time after closing of sai exhaust port.

2. In combination with a furnace having a fir ing opening, a fuel supporting distributor plate in said firing opening, a fuel distributor head provided with jet openings directed across said plate for projecting fuel therefrom over the-fire in said furnace, a door for the firing opening, a supply line for delivering fluid under pressure to said distributor head, a fluid operated valve interposed in said supply line controlling the flow of fluid to said distributor head, said valve comprising a casing provided with a fluid inlet port and a fluid outlet port, said ports communicating with said supply line, a valve element com rising spaced piston heads rigidly secured together mounted for reciprocation in said casing, means at one end of said valve element for moving it to a position establishing substantially immediate communication between said inlet and outlet ports,'whereby fluid under pressure will pass throughsaid supply line to said distributor head,

a passage discharging at the other end of said valve element for passing a portion of the fluid under pressure delivered to said casing from said inlet port to the said other end of said valve element, thereby moving the valve element to a position closing said outlet port and interrupting 7 pressure from the said other end of said valve element, means responsive to opening and closing of the door for opening and closing of said exhaust port, and means in said passage restricting the flow of fluid under pressure to the said other end of said valve element whereby movement of of fluid to said distributor head, said valve comprising a casing provided with a fluid inlet port and a fluid outlet port, said ports communicating with said supply line, a valve element comprising mounted for reciprocation in said casing, means at one end of said valve element formoving it to a position establishing substantially immediate communication between said inlet and outlet ports, whereby fluid under pressure will pass through said supply line to said distributor head, a passage in said valve element discharging at the other end of said valve element for passing a portion of the fluid under pressure delivered to said casing from said inlet port to the said other end of said valve element, thereby moving the valve element to a position closing said outlet port and interrupting the passage of fluid under pressure through said supply line to said distributor head, said casing having an exhaust port for venting fluid under pressure from the said other end of said valve element, means responsive to opening and closing of the door for openspaced piston heads rigidly secured together,

ing and closing of said exhaust port, and means in said passage restricting the flow of fluid under pressure to the said other end of said valve element whereby movement of said valve element to close said outlet port is delayedan interval of time after closing of said door.

4. In combination with a furnace having a flring opening, a fuel supporting distributor plate to said distributor head, a fluidoperated valve interposed in said supply line controlling the flow of fluid to said distributor head, said valve comprising a casing provided with a fluid inlet port and a fluid outlet port, said ports' communicating with'said supply line, a valve element comprising spaced piston heads rigidly secured together mounted for reciprocation in said casing, means at one end of said valve element for moving it to a position establishing substantially immediate communication between said inlet and outlet ports, whereby fluid under pressure will pass through said supply line to said distributor head, a passage discharging at the other end of said valve element for passing a portion of the fluid under pressure delivered to said casing from said inlet port to-the said other end of said valve element, thereby moving the valve element to a position closing said outlet port and interrupting the passage of fluid under pressure through said supply line to said distributor head, said cas ing having an exhaust port for venting fluid under pressure from the said other end of said valve element, means responsive to opening and closing of the door for opening and closing of.said exhaust port, said passage being formed to restrict the flow of fluid under pressure to the said other end of said valve element whereby movement of said valve element to close said outlet port is delayed aninterval of time after closing of said door, and a needle valve in said passage for regulating the said interval of time.

O'I'I'O MOELLEB.

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