US2483689A - Bullock - Google Patents

Description

Oct. 4, 1949. BULLQCK 2,483,689

COMBUS TION CONTROL Filed May 18, 1945 $51188S-$h89t l Fuel Feed Primary Azr Fig.

ELLIS. BULL UEK INVENTORJ Oct. 4, 1949. E. BULLOCK 2,483,639

COMBUSTION CONTROL Filed May 18, 1945 5 Sheets-Sheet 2 ELL15.'BUL Li] C K INVENTOR.

wzw 9 ATTUR' Y COMBUSTION CONTROL Filed May 18, 1945 3 Sheets-Sheet 3 ELLIE- BULL EIEK INVENTOR.

AT El NEY Patented Oct. 4, 1949 COMBUSTION CONTROL Ellis Bullock, Birmingham, Ala., assignor to Fly Ash Arrester Corporation, a corporation of Alabama Application May 18, 1945, Serial No. 594,558

.6 Claims. (01. 23624.5)

This invention relates to a boiler furnace control governed jointly by the pressure in the boiler and the flow of steam being used. One object of my invention is to provide mechanism of the character described which shall be sensitive to changes in pressure and flow, and positive in its action to operate a controlling element associated with the furnace.

A further object of my invention is to provide a boiler furnace control which shall be adapted, upon a variation of the static pressure, or in the flow of steam from the boiler, or both, to exercise a controlling function over a plurality of furnace control devices.

A still further object of my invention is to provide a boiler furnace control utilizing a manometer tube in which the liquid level in the tube is a function of the flow of steam, together with photo-electric cells disposed to initiate a control movement responsive to a change of liquid level in the manometer tube which movement changes the positions of the said cells, together with means operable responsive to a change of static pressure in the boiler to further vary the relative positions of the photo-electric cells relative to the tube.

Briefly, my invention comprises a manometer tube which may be a single tube or a U tube disposed to register the flow of steam in a steam supply conduit from the boiler, in-a manner well understood, by the height of mercury in the tube. I mount a pair of photo-electric cells, each with an associated movablelight source, each cell and its associated light source being movable vertically alongside the tube. The photo-electric cells and their associated light sources are mounted on a frame for joint movement and are suspended from a pulley by a flexible suspension member, the pulley being driven by an electric motor controlled by the photo-electric cells responsive to the height of mercury in the tube. The positions of the photo-electric cells and their associated light sources are further modified by means of a device responsive to the static pressure in the boiler. Operatively connected to the motor are a plurality of furnace control devices which are actuated by the motor responsive to the positions assumed by the photo-electric cells. I thus provide a boiler furnace control which operates responsive to the flow of steam from the boiler, r

Fig. l is an elevational view, partly diagrammatic;

Fig. 1 is a detail section taken along line I -J of Fig. 1;

Fig. 2 is an elevational view taken at right angles to Fig. 1;

Fig. 3 is a wiring diagram showing the motor controls;

Fig. 4 is a view similar to Fig. 1 showing a modified form of my invention; and

Fig. 5 is a sectional view taken along the line VV of Fig. 4.

Referring now to the drawings for a better understanding of my invention, I show in Fig. 1 a fragment of a boiler l0 having a steam supply line or conduit I l' leading therefrom. The steam supply conduit II has disposed therein an orifice l2 and connected to the upstream side of the orifice is a conduit l3, and to the downstream side a conduit M, the conduits I3 and I4 being connected at their lower ends to glass tube sections l6 and I! joined together at their lower ends by a shorter U connection Hi, all being secured to a panel 20.

At I9 I show a photo-electric cell mounted in a frame 2i which also carries a light 22 which directs its beam through the glass section l6 of the U tube toward the cell H). The frame 2| is adapted to move vertically in guides 23 and 25, which are mounted on the panel 20. At 26 I shOW a similar photo-electric cell mounted on a frame 21 which also carries a light 28 similar to the light 22 and which is directed through the glass section ll of the U tube towards the photo-electric cell 26. The frame 21 is mounted to move vertically in guides 29 and 3|, which are mounted on the panel 20 and are similar in all respects to guides 23 and 24. Both the frames 2| and 21 are suspended from a sprocket chain 32 which passes upwardly over idler sprockets 33 and 34 and thence around a driving sprocket 36 driven by a geared reversing motor 31.

In Fig. 3 I show by way of example, an electric supply circuit 38 from which circuits 39 and 41 lead to the light sources 22 and 28 respectively. The motor 31 is controlled by means of circuits 42 and 43, opened and closed respectively by magnetic switches 44 and 45. The switches 44 and 46 are operated respectively by the photo-electric cells [9 and 26, and preferably include delayed closing dashpots 44' and 46'. The switches 44 and 46 are normally open when the cells l9 and 26 are energized. Such arrangements of magnetic switches and photo-electric cells are well known in the art and are commercially available. Ac-

cordingly, no detailed description thereof is deemed necessary. A conductor 41 leads from the circuit 33 through the photo-electric cell I!) to the coil 48 of the switch 44 and thence back to the circuit 38. A conductor 49 leads from the circuit 38 through the photo-electric cell 28 to the coil 5| of the switch 46 and thence back to the circuit 33. When the mercury in the glass sections I6 and H of the U tube is at such level that the light beams from the light sources 22 and 28 strike their associated photo-electric cells l9 and 26, the switches 44 and 46 are both opened, as shown in Fig. 3. When the mercury rises in either glass section sufficiently to intercept the beam of light from the light source to the associated photo-electric cell, the associated switch and motor circuits are closed. This action is utilized to actuate the furnace controls as more particularly pointed out hereafter.

It will be understood that the electrical circuits herein shown and described are for the purpose of illustration only and that the details thereof form not part of my invention. Various changes may be made therein and still effect the control of, the motor 37 by the photo-electric cells as herein contemplated;

At 52 I show. a. diaphragm mounted within a casing 53 connected to the boiler It by means of a conduit 54. The diaphragm 52 actuates a stem 56 connected thereto. which passes outwardly through an adjusting sleeve. 51'. A spring 58 is disposedbetween the diaphragm 52 and the sleeve 51 to resist the outward movement of the diaphragm. 52', and is adjusted by means of the sleeve 51'. The stem is connected to av lever 59 pivoted at 68 which in turn is, connected to a yoke 6|, mounted in guides 62 and B3. Mounted on the yoke, 31! are idler pullers 64 and 66,, which bear against, the two reaches of the sprocket chain 32. Upon an increase of boiler pressure, the diaphragm causes the yoke GI to move slightly to, the right, as viewed in Fig. 1, thereby slightly raising the frame 2] with its, photo-electric cell. 9=and lowering the frame 2'! with its. photo-elec tric, cell 26. Upon a, decrease of steam pressure 4:;

in the boiler It, a reverse of the movement just described occurs. The diaphragm 52 is moved toward the right by the spring 58,, thereby movs. h yoke 6! with its idlers. 64 and. 56 towardtheljeftthlls raising the, frame 21 with its photo-- electric cell 26 and lowering thev frame 2] with its photo-electric cell l9.

Driven by the motor 3.! is a pinion 61 which meshes Witha. rack. 58,.mounted. to move vertically and held in. place by a roller H. The rack 63 is .i-J;

connected to a rod. 12, whichv in turn has mounted thereon pistons. 13, 'M, and 16 mounted, respectively, in hydraulic cylinders 11, 78,, and 19., The hydraulic cylinder if! is connected at. its ends to a. similar hydraulic cylinder 8| by means of conduits 82 and, 83... Apiston 24' in the cylinder 8| is mounted on a rod B76. extending out at the ends thereof sothat any moyement of the piston 13 in the cylinder IT effects a similar, opposite movement of the piston 84in the cylinder 8 I. The cylinder 78' is likewise similarly connected by means of'conduits 87 and 88 to a hydraulic cylinder 89 having a piston 9,1; mounted therein Which is mounted on a piston rod 92 extending out of the ends thereof. Thus any movement of the piston 14 in the hydraulic cylinder 78 effects a similar. moyemenuin an opposite direction, of the piston 9! in the cylinder 89; The cylinder 79 is simi larly connected by means. off conduits 93 and 94 to a hydraulic. cylinder. 9.6. hav ng a. p t n. 9'1

therein mounted on a piston rod 98 which extends out through the ends thereof. Thus any movement of the piston 76 in the hydraulic cylinder (9 effects a similar movement in an opposite direction, by the piston 91 in the cylinder 95. Any suitable furnace controls may be connected to the piston rods 86, 92, and 98, such as the up-take dampen, fuel feed. and primary air supply indicated in the drawing.

From the foregoing description, the operation of my improved apparatus as so far described will be readily understood. With constant steam flow and pressure, the mercury in the sections l6 and t? of the U. tube will be in such a position that the beams from the. light sources 22 and 28 strike the photo-electric cells l9 and 26, and the relay switches 44 and 45 remain open. Assume now an increased flowof steam due to an increased demand, the pressure in the section [6 of the U tube decreases relative to the pressure in the section ll so that the mercury falls in the section I! and rises, in the section 15 thus intercepting the rays of light from the light: source 22 to the photoelectric cell it. When this occurs, the switch 44: is closed thus energizing the motor 31', which begins turning clockwise to raise the frame 21- and lower the frame 27. This movement continues until the light rays from the source 22 again strike the photo-electric, cell [9 whereupon the switch as is again opened and the motor stopped. If, during the movement just described, the boiler pressure increases, the diaphragm 52 moves toward the left with the rod 56, which causes the yoke E! with the i'cllers 64" and 68; to move to the right. This raises the frame 2k and: lowers the frame 2?, and thus. modifies the movement proed by an increased; flow, just described. As

motor 3! turns clockwise, as described, the

rack 53 is forced downward with the piston rod.

72' and pistons 13', 14 and 16 thus effecting movement of the pistons 84, 9| and 9! and simultaneously changing, the setting of the furnace control devices indicated, for example, by opening the-uptake damper, and by increasing the supply fuel and primary air.

Should there be a decrease in steam demand, thus bringing about a decrease in flow ofsteam, there is a relative increase, in pressure inthe section Ifiof'the. U tube. This causes the level of the mercury in the section. L6 to be lowered and the. level in the section I]. to be raised. Raising the level of the mercury in the section l'lintercepts the light beam from the light source 28-, whereupon the switch 46 is closed, closing the circuit 43 to the motor 37-. This; causes the motor 31: to rotate counterclockwise, raisingtheframe 2'1 with the photo-electric cell 26-and-lighttsource 28111117111 the beam from the light source 28: again strikes the photo-electric cell 26, whereupon the photoelectric cell 26' is again energized and the relay switch. 46 is opened stopping the motor 31. As the motor 37 rotates counter-clockwise; it raises the rack 38 with the piston rod-12 and pistons 13,

. l4 and 16, which brings about a. lowering of the pistons 84', SI, and 91 in the cylinders 81, 89 and 96, thus changing the setting of the furnace control' devices to compensate for the decreased demand.

While in the foregoing description, I have set forth my invention as including a U tube type of. manometer, it is equally applicable to a single tube type. In Figs. 4 and. 5 of the drawinel show a modified form of my. inventionv in. which photo-- "52- electric cells Hll and,l 02 are locatedtimaeframe I03:

having mounted therein light sources I 04 and IE6, the light sources being directed across a single glass manometer tube section I 01. The frame I03 in which the photo-electric cells are mounted is suspended from a pulley or sprocket I09, driven by the motor 31. A sprocket chain III connects the sprocket I09 to the frame I03 and passes over an idler H2.

The light source I04 and the photo-electric cell I02 are disposed in the frame I03 at a slightly lower level than the light source I06 and the photo-electric cell I0 I. The glass tube section I0'I forms a part of a well-known form of manome er which is connected to the conduit II at H4 on the downstream side of the orifice I2. The glass section I01 is connected at its lower end to a horizontally extending conduit I I6 leading to a vessel II1 containing mercury. The vessel H1 is connected to the conduit I08 and with the conduit I I at connection I I3. It will thus be seen that the level of the mercury in the glass section I 01 rises and falls responsive to the flow of steam in the conduit II. The control of the motor 31 is the same as previously described and as illustrated in Fig. 3 of the drawing. the photo-electric cells IM and I02 exercising the same control as the photo-electric cells I9 and 26 in the previously described embodiment. with the exception that the photo-electric cell I02 which is normally below the level of the mercury in the glass section I01 acts to close the ma:- netic switch 46 when the level of the mercury falls below the light source I04. The photo-electric cell IOI acts to close the magnetic Switch 44 w ible member, said cells being disposed whereby the level of the mercury in the glass section I0'I rises above the level of the light I06. The end of the sprocket chain II I in connected at H9 to the sprocket I09 whereby, as the motor 31 is rotated responsive to the action of the photo-electric cells I [II and I02, when the mercury level rises and falls in the glass section I01, the frame I08 is raised and lowered accordingly. A rack 68 is connected to a piston rod I2 which in turn is connected to pistons I3, 14' and I6, as described in the previous modification of my invention. The furnace controls may be connected to the pistons in the manner already described in the previous modification. Also, a yoke 6| connected to a pressure responsive device, not shown, carries an idler 64' which acts against the sprocket chain I I I to modify the action of the photo-electric cells.

From the foregoing, it will be apparent that I have devised an improved boiler furnace control which is simple of design, sturdy of construction, and one which is extremely sensitive to changes of flow, or steam demand, and to pressure in the boiler, or source of supply.

While I have shown my invention in but two forms, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various other changes and modifications, without departing from the spirit thereof, and I desire, therefore, that only such limitations shall be placed thereupon as are specifically set forth in the appended claims.

What I claim is:

1. In a control for a steam boiler furnace, a steam supply conduit from the boiler, a manometer tube disposed to register the fiow of steam in the conduit by the height or" a liquid in the said tube, a motor, photo-electric cells together with light sources therefor for controlling the motor and mounted for up and down movement along said manometer tube by the motor responsive to the rise and fall of liquid in said tube, furnace control devices actuated by the motor, and a device having an element movable responsive to pressure in the boiler and operatively connected to the photo-electric cells to modify their positions.

2. In a control for a steam boiler furnace, a steam supply conduit from the boiler, a manometer tube disposed to register the flow of steam in the conduit by the height of a liquid in said tube, a pair of photo-electric cells together with associated light sources associated with the tube and movable up and down along said tube, said cells being so disposed that one with its associated light source is normally below the level of the liquid in the tube and the other is normally above the liquid level in the tube, a reversible motor operatively connected to the cells and controlled by the energization and de-enerization of the cells to raise and lower them responsive to variations in the level of liquid in the tube, a device movable responsive to static pressure in the boiler operatively connected to the cells to modify the positions thereof, and furnace control devices actuated by the motor.

3. In a control for a steam supply conduit from the boiler, a manometer tube disposed to I register the flow of steam in the conduit by the height of a liquid in said tube, a pair of photoelectric cells together with associated light sources positioned for movement along said tube and suspended from a pulley by a common flexated by the rack, and a plurality of furnace control devices operatively connected to the hydraulic transmission devices.

4. In a control for a steam boiler furnace, a steam supply conduit from the boiler, a U tube disposed to register the flow of steam in the conduit by the height of a liquid in the legs of said tube, a pair of photo-electric cells together With associated light sources mounted one each opposite a leg of the U tube and suspended from a pulley by a common flexible member, each of said cells being adapted to be energized when the liquid level in the associated leg of the tube falls below the level of the cell, a relay controlled by each cell, a reversible motor operatively connected to the pulley and so connected to the relays that deenergization of the respective cells causes rotation of said motor in opposite directions to move said cells vertically responsive to variations in the level of liquid in the legs of the U tube, means movable responsive to variations in static pressure in the boiler for modifying vertically the positions of the photo-electric cells, a plurality of furnace control devices, a hydraulic cylinder and piston for operating each of said devices, a rack actuated by the motor, and a plurality of hydraulic cylinders and pistons connected to the rack and hydraulically connected each to one of the first mentioned hydraulic cylinders.

aeeaesa 5:. Apparatus as defined. in claim 2 in which the photo-electric cellsare suspended from a pulley actuated by the motor to rise and fall with variations in the: height of liquid in the tube together with the furnace control devices actuated by the motor.

6. In a control for a steam supply conduit from the boiler, a manometer tube disposed to register the fiowof steam in the conduit by the height of a liquid in said tube, a pair of photoelectric cells together with associated light sources positioned for movement along said tube and suspended irom a pulley by a common flexible member, said cells and their associated light sources being disposed for one to be normally below the liquid level in the tube and the other is normally above the liquid level in the tube, a reversible motor operatively connected to the pulley and controlled by the energization of the cells to move them up and down responsive to variations in the level of liquid in the tube, a rack actuated by the motor, a plurality of hydraulic transmission devices actuated by the 8 rack, a: plurality of furnace control devicesoperatively' connected: to the hydraulic transmission: devices, and: means: movable responsive to variations in static pressure in the boiler for modifying" vertically the positions: of the photoelectric cells.

ELLIS BULLOCK.

REFERENCES CITED Thefollowing references are of? record in the file 01? this patent:

UNITED STATES PATENTS

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