US2089704A - Stoker actuating motor - Google Patents

Description

Aug. 10, 1937. H. s. MORTON STOKER ACTUATING MOTOR 2 Sheets-Sheet 1 Filed NOV. 23, 1932 Patented Aug. 10, 1937 UNITED STATES STOKER ACTUATKNG MOTOR Application November 23, 1932, Serial No. 643,997

2 Claims.

This is a device for stoker control, regulated by fuel bed resistance in a simplified form wherein a speed controlling means may be eliminated so as to permit the stoker mechanism to either run 5 full speed or stop entirely, depending on the condition of the fire.

In one form, the principle of operation is similar to that where a speed control means is used in so far as the method of by-passing the hy- 'draulic operating fluid, however, with this simplified control for stokers, a means is provided which will regulate the stoker operating controller so that the fuel bed may be maintained more uniform in an easy and practical manner.

It is a feature to provide a controller wherein the hydraulic fluid ejected under pressure from a normally constantly operated source of creating hydraulic pressure is regulated by the controller which is operated by the condition of the fuel bed or by the fuel bed resistance. In this construction of the stoker regulating means when the fuel bed is low and the air resistance through the same from the windbox of the stoker dey creases so that the air passes more freely through the same, the exhaust valve of the controller is closed automatically, whereupon the stoker piston is caused to be operated by the fluid pressure from the source of supply.

It is also a feature to operate the piston which reciprocates the stoker ram to cause the ram to always stop in the throat of the stoker, closing the same. 7

Further, I provide a means for regulating the reciprocation of the ram of a stoker to operate the same in accordance with the fuel bed resistance so that when the resistance in the fuel bed decreases, the ram will be operated and feed fuel to the fire box so as to build up the fuel on the tuyeres of the fire box and thereby increase the resistance to the desired point, whereupon the fuel feeding means is stopped automatically at a predetermined point. Thus the fuel bed resistance operates to regulate the controller which in turn regulates the feeding of fuel.

The stoker controller may be in a form which combines the full speed simple regulating device in the controller itself with a speed valve so that under certain conditions where it may be desirable the speed valve may be set so that the controller will operate the stoker fuel feeding means in accordance with the setting of the speed valve rather than in the simplest form where only the full speed exhaust valve has the complete control. Thus the combination of the full speed valve'with a speed controlling valve may be in- (CI. 12l.164)

cluded in a single stoker controller to provide a more efficient means of regulating the feeding of fuel of a stoker.

I have provided a different type of controller, illustrated in Patent 2,047,832, dated July 14, 5 1936.

In the drawings forming part of this specification:

Figure 1 illustrates diagrammatically and partly in section, a stoker fuel feeding means in con- 10 nection with a furnace, fuel hopper, and a simple form of my hydraulic controller.

Figure 2 illustrates diagrammatically and enlarged and in section, the simplest form of my stoker hydraulic controller and the associated 15 parts.

Figure 3 illustrates diagrammatically a sectional view, showing a modified form of controller, which combines the simple full speed operating mechanism with a speed Valve in a single device, 20 and shows the same connected with associated operating members.

The constructions illustrated have a means of controlling the stoker feeding mechanism so as to stop the feeding member or ram in the throat 25 of the stoker to close the same to prevent the fire from creeping back into the throat and in turn into the fuel feeding hopper.

This is a device for controlling a stoker fuel feeding means so as to build up the fuel bed re- 30 sistance when the same lowers in the burning of the fire in thefurnace and is particularly adapted to a simple form of control which permits the feeding of the fuel to the tuyeres of the furnace quickly by the full operation of the stoking means until the fuel bed resistance becomes normal or to a point desired. Thus I maintain a better and more even fire in the furnace.

The simple form of control may be combined with a speed control valve to give all the advan- 40 tages of both the simple form and the speed control valve in one controller if it is desired, as will be more fully hereinafter set forth.

The drawings illustrate the stoker control A which is adapted to control the hydraulic pressure in a manner so that it will regulate the piston it within the cylinder ll of the stoker feeding means C to cause hydraulic pressure coming from a source of supply to operate the piston 5 whenever it is desired to have the fuel feeding means C operate. When the controller A operates to cause the piston ill to operate it will maintain the fuel feeding operation in full speed until ie controller A causes the fluid under hydraulic pressure to be directed in a manner to stop the piston it].

The fuel feeding means C includes the piston l and the cylinder ll together with the rod l2 which is connected to the fuel feeding ram is and on the inner end of which a fuel feeding pusher i4 is carried which extends into the retort I5 of the stoker B positioned in the furnace D. The ram is adapted to operate through the lower end of the fuel hopper E and into the throat N5 of the stoker B. The ram I3 is caused to normally stop with the inner end of the ram is closing the outer neck ll of the throat 5 so as to prevent the fire from the furnace D creeping back to the fuel hopper E when the stoking means is at rest.

The stoker B is formed with a series of tuyeres it which are of an ordinary form, having openings through which air is blown from the windbox F of the stoker B to feed air through the fuel bed extending over the tuyeres in regulating the fire in the furnace D.

A suitable blower G may be provided to new air into the windbox F, and within the tube i9 which leads from the blower G to the windbox F, I provide a Venturi tube 2i! which operates in connection with an adjustable damper 2| restricting the opening in the tube i9 adjacent the Venturi tube 29 to cause the air from the blower G to be passed through the tube 25! so as to provide a means of detecting the change in velocity of air through the air feeding tube !9 and out of the windbox F and through the tuyeres it. When the fuel bed on the tuyeres l8 lowers or thins down, the air resistance through the same will be less and when the fuel bed builds up, the air resistance through the fuel bed will be greater. This will be instantly detected by the venturi 253 which is connected by the tube 22 to the bell 23, causing the same to operate the lever 24. The lever 26 is adjustably connected on one end to the exhaust valve 25 of the controller A.

' exhaust valve 25 to draw the same into the dotted position illustrated in Figure 2, closing the exhaust port 26 in the controller A.

In the use of the hydraulic controller A fluid under hydraulic pressure is normally directed from the tube 21 in one end of the cylinder it toward the piston Hi. This fluid under hydraulic pressure may be supplied by any suitable means into the cylinder 8 i and may operate continuously to maintain fluid under hydraulic pressure for operating the piston when it is desired. When the exhaust valve 25 of the controller A is in the full line position illustrated in Figure 2, the fluid under hydraulic pressure will not operate the piston ll! because the fluid under hydraulic pressure is permitted to pass through the pipe 28 into the chamber 29 in the controller A and thence through the opening 36 and the passageway 35 into the passageway 32 and out of the exhaust port 25. The exhaust valve 25 is formed with a pair of cylindrical or piston ends 33 which are spaced apart by the connecting rod 34. The extended end of the rod 34 acts as a stop to limit movement of the valve 25 in one direction.

If the bell 23 has been operated by the increased velocity through the tube 26 by the decrease of air resistance through the fuel bed on the tuyeres it so as to move the exhaust valve 25 to close the exhaust port 26, then the fluid under pressure coming in through the pipe 27 will first pass up through the tube 28 into the controller A. The fluid pressure will build up in the passageway 29 passing through the passageway 30 and into the passageway 3i, and then being prevented from exhausting through the exhaust port 25, fluid under pressure will be caused to pass through the opening and into the chamber 35 on one side of the floating piston 3'5 to force the same down against the ball check 38 to hold the same closed, and then the fluid pressure built up in the controller A not being released because the exhaust valve is closed and the check valve 33 is closed, will cause the piston id to start to reciprocate back and forth which it will continue to do until the exhaust valve 25 again opens by the decrease of velocity through the venturi 2i! and the bell 23 moving back to normal position. The pressure fluid passes through a conventional reversing valve 80 shown in Figure 3 which is connected to the cylinder H on one end by the passage or tube 2? and to the other end by the passage or tube 39. The reversing valve 86 1s centrally connected at 8! to a suitable source of supply of fluid under pressure. The valve piston 82 is provided with a rod 83 operated by movement of the piston rod l2 to move the piston 32, to direct fluid under pressure alternately to passages 21 and 39, to reverse the piston id at the end, of each stroke. The valve $2 also connects the low pressure end of the cylinder H through a passage 2? or 39 to an exhaust port 84, the valve 3t thus always maintaining one end of the cylinder H on one side of the piston iii connected to the source of supply of fluid under pressure and the other end of the cylinder ii on the other side of the piston if! to the exhaust. Thus the piston iii with the rod l 2 is caused to reciprocate back and forth, carrying the fuel plunger it back and forth in the fuel hopper E to stoke the fuel through the throat it into the retort l5 and onto the tuyeres When the controller A operates as just described to cause the fuel feeding mechanism C to be operated as set forth, the mechanism C is operated at full speed until the fuel bed resistance on the tuyeres l8 becomes normal and then the piston iii will come to rest in a position at the right end of the cylinder illustrated in Figure 3 with the rain 53 closing the neck 5? of the throat Hi. The ram always stops in this position and is caused to do so by the connecting tube ill which carries fluid under pressure from the tube 39 up into the passage il of the controller A and against the ball check 38 which closes the passage 29 and causes the piston iii to continue until it is in the position illustrated in Figure 3 and the reversing valve directs fluid under pressure to the other side of the piston through the tube 21. By this time the exhaust valve 25 of the controller A has opened, as illustrated in full linesin Figure 2, and instead of the fluid under pressure from the tube 2? causing the piston to operate, it will be by-passed out through the exhaust opening 26 of the controller A and will continue to exhaust out of this opening until the exhaust valve has again been operated by the bell 23 to close the opening .26, whereupon the fuel feeding mechanism C will imm diately begin to operate. All of these operations are automatic and continue to maintain a uniform fuel bed on the tuyeres iii of the stoker B. 1

The controller A is provided with an adjustable stop screw 52 which limits the movement in one direction of the piston 37 to vary the time reall quired to close the ball check 38. When the exhaust valve 25 is open some of the fluid from the passageway 29 can pass up under the check valve 38, the floating piston 3'5 having moved to permit the valve 38 to open, permitting part of the pressure to be exhausted out of the pipe 46.

The controller may be built up in the form illustrated in Figure 3 with the exhaust valve 25 in position across one end of the controller A instead of on one side thereof. In this form the bell 23 is connected by the link and lever 66 to the valve 25' and the valve is normally limited by the stop in its movement in one direction, and by the extension of the rod 34' on one end.

In the controller A in Figure 3, I have provided a speed controlling valve 38 which is operated by the hand lever 49 to set the same in the controller A. In this construction the intake pipe 28 which supplies the pressure to one side of the controller A directs the fluid toward the tapered head 58 of the valve 68, some of which fluid passes toward the end 5! of the valve 58 and out of the passageway 52 through the passageway 53, past the check valve 38 and out of the passageway 40 on the other side of the controller A. An adjusting bell crank stop 54 which is controlled by the screw 55 is also supplied in this controller and the floating piston 25'! is adapted to bear against one end of the bell crank 54 when holding the valve 38 closed.

Normally the speed control valve 48 is set in wide open position which permits the fluid to come up through the tube 28 and through the passageway 56, thence through the passageway 57, past the ball check 58, out of the port 59, and out of the exhaust port 6%. In this controller A the operation is the same as that described in the form of the controller illustrated in Figure 2. When the exhaust valve 25' closes the port 53 the fluid will be locked in the controller A and cause the piston it to begin to operate. This construction of the controller will also cause the piston to stop at its normal position, at the right end of the cylinder ll illustrated in Figure 3, with the ram l3 closing the neck ll of the stoker.

When it is desired to use the speed control valve 48 the stop til is dropped down so that the exhaust valve 25 may be moved as far as the stop 6% when the bell 23 operates the valve 25'. The

v speed valve is set by the handle 29 so that a certain amount of fluid will pass the tapered head 5% and with the valve 25' over against the stop 6! the exhaust port Bil is closed and the passageway 5'5 is connected through the valve chamber directly with the port 59, permitting fluid to pass from the passageway 57 through the port 59 and moving the floating piston 37 in position to close the check valve 38. This takes a certain period of time in accordance with the setting of the valve If the valve is is set so as to take a minute or any other space of time to direct suincient fluid under pressure to the floating piston 3? to move it into the dotted position, that is the period that the piston H3 is at rest. When the fluid under pressure is directed to the other side of the piston through the tube 39 the fluid pressure in the tube 4% causes the floating piston 55'! to move to the full line position almost instantly and continues the operation of the piston 18 to the other end of the cylinder H, and the operation repeats which was just described, leaving the piston ill at rest until the floating piston 37 has again been moved to the dotted line position in Figure 3. As the piston 31' moves up- Wardly, the fluid above this piston is forced through the passage 59, down the passage 51, past the check valve 85, through passage 52, and to the passage 28, which is connected to the right end of the cylinder H. The right end of the cylinder H is under these conditions connected to an exhaust port 84 in the reversing valve 80. Fluid under pressure in passage ill cannot pass piston 32, and closes the check valve 38. As the piston 16 moves to the right, there is no n w of liquid through passage 53.

As soon as the bell 23' has been released back to normal position the exhaust valve 25 will move to normal full line position in Figure 3 and the fluid coming in through the pipe 28' will be exhausted out of the exhaust port 58.

lhus the construction of the controller A in Figure 3 combines the speed control valve Q8 and the exhaust valve 25'. This controller may be operated without using the speed control valve 58, causing it to operate in the simple manner and with the same functions as the controller disclosed in Figure 2, or it may be used as just described in combination with the exhaust valve 25, thus causing the fuel feeding mechanism C to operate intermittently until the fuel bed becomes normal on the tuyeres l8.

While the simplest form of controller A such as is illustrated in Figure 2, may be desirable, and which is also illustrated diagrammatically in Fig ure 1, it is equally true that the controller such as illustrated in Figure 3 may be desirable. Each of the controls operate to maintain a uniform fuel bed resistance on the tuyeres l3 and it is desirable that this be done in a very simple and effective manner, the operations of which are automatic and positive to give complete stoker control.

I have described the construction and features of my controlling means in accordance with the patent statutes, and the application thereof together with variations of an obvious character should be apparent and considered within the scope of the following claims.

I claim:

1. A control for a hydraulically operable piston reciprocable in a cylinder including a valve cylinder, means connecting one end of said valve cylinder to one end of said cylinder, means connecting the other end of said cylinder to the other end of said valve cylinder, a by pass between said last named means and said one end of said valve cylinder, a check valve in said by pass, a piston in said valve cylinder for operating said check valve in one extreme position. and exhaust valve means in said means connecting said other ends of said cylinder and said valve cylinder for exhausting the pressure therein to prevent operation of said valve piston.

2. A control for a hydraulically operable piston reciprccable in a cylinder including a valve cylinder, means connecting one end of said valve cylinder to one end of said cylinder, means connecting the other ends of said cylinder and Valve cylinder together, a by pass between said last named connecting means and said one end of said valve cylinder, a check valve in said by pass, a

iston movable in said valve cylinder operable to close said check valve in one extreme position, said piston being operable by pressure of fluid in said last named connecting means, and exhaust valve means in said last named connecting means operable to prevent building up of pressure therein.

HAROLD S. MORTON.

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