US732031A - Apparatus for feeding fine fuel to furnaces. - Google Patents

Description

No. 732,031. PATBNTED JUNE so, 1903. J. E. BALDWIN, P. N. VAN ZANDT 8; A. v. T. DAY. APPARATUS FOR FEEDING FINE FUEL T0 FURNACES.

APPLLOATION FILED JUNE 24, 1901.

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APPARATUS FOR FEEDING FINE FUEL T0 FURNACES.

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J. B; BALDWIN, F. N. VAN ZANDT & A. V. T. DAY. APPARATUS FOR FEEDING FINE FUEL T0 FURNACES.

APPLICATION FILED JUNE 24, 1901.

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No. 732,031. PATBNTED JUNE 30, 1903.

J. E. BALDWIN, F. N. VAN ZANDTA: A. V. T. DAY.

APPARATUS FOR FEEDING FINE FUEL TO FURNACES.

APPLIUATION FILED JUNE 24, 1901.

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N0 MODEL.

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UNITED ST TES Patented .Tune 30, 190i PATENT OFFICE.

.IAMEs BALDWIN, FREDERICK N. VAN ZANDT, AND ALBERT v. T. DAY, OF BROOKLYN, NEW YORK, ASSIGNORS TO THE IDEAL FUEL-FEEDER COMPANY, OF BROOKLYN, NEW YORK, A CORPORATION OF NEW YORK.

APPARATUS FOR FEEDING FINE FUEL T O FURNACES.

SPECIFICATIGN forming part of Letters Patent N 0. 732,031, dated June 30, 1903.

Application filed June 24. 1901. Serial No.65,809. (No model.)

To all 10/1/0777, it may concern:

Be it known that we, JAMES E. BALDWIN, FREDERICK N.VAN ZANDT, and ALBERT V. T. DAY, citizens of the United States, residing at Brooklyn, in the county of Kings and Stateof' New York,have invented certain new and useful Improvements in Apparatus for Feeding Fine Fuel to Furnaces; and we do hereby declare the following to be a full, clear, and exact description of the invention, such as will enable others skilled in the art to which it appertains to make and use the same.

Our invention relates to improvements in that class of automatic stokers in which the fuel is reduced to a pulverized condition, mixed with air, and discharged into a combus tionchamber and in which a preliminary breaking or grinding apparatus is employed,- together with pulverizing, aerating, and dis- 2o charging apparatus. The function of the preliminary breaking or grinding apparatus in this class of stokers is to break or grind the fuel and then feed it to the pulverizing appa ratus. The difficulties which have arisen in the past in connection with such breaking or grinding apparatus are as follows: first, clogging of coal when wet; second, inability to redues to a sufficient degree of fineness, result-' ingin the consumption ofan excessiveamount of power in the pulverizing apparatus; third, difficulty of controlling the amount of fuel delivered by the breaking or grinding apparatus to the pulverizer; fourth, breakage orstoppage resulting from the presence of hard for- 5 eign substance, such as iron, &c., in the fuel and the difficulty of removing the same when lodged in the breaking or grinding apparatus.

The object of our invention is to provide a breaking and grinding apparatus in which these difficulties will be overcome.

In general terms our invention may be described as follows: Initial positive breaking or crushing apparatus is provided, communicating with which is a secondary positive 5 grinding mechanism for further reducing the fuel to the finest degree practically attainable before delivery to the pulverizing apparatus and for feeding the same thereto by positive action. Interposed between the initial breaker and the secondary grinder is an adjustable feed-regulating device for controlling the amount of fuel delivered from the breaker to the secondary grinder and thence to the pulverizer. The breaking and grinding apparatus is provided with an outer casing comprising separable parts normally forming part of the casing proper, but adapted to be removed from their normal positions and the casing thereby opened in order to secure access to the inner mechanism for the purpose of removing foreign substances.

The mechanism and construction disclosed in the following description and claims and illustrated by' the accompanying drawings represent the best mode in which we have applied the principle of our invention.

In said drawings, Figure l is an end elevation of our improved breaking, grinding, and feeding apparatus. Fig. 2'is a vertical central sectional view of the same and from the same point of view as that of Fig. 1. Fig. 3 shows a similar section taken on a plane at right angles to the plane of the section in Fig. 2. Fig. 4 is a top plan view of the apparatus. Fig. 5 shows a horizontal section on line 5 5 of Fig. 3. Fig. 6 shows a horizontal section On line 6 6 of Fig. 3. Fig. 7 is a detail view showing the action of the teeth-of the grinding-rings. Fig. 7 is an enlarged detailsection through the grinding-rings. Fig. 8 is a vertical central longitudinal sectional view showing the breaking, feed-regulating, grinding, pnlverizing and aerating, and ejecting apparatus of the entire machine. 1

Following is a specific description of the invention as embodied in the construction illusportions of .the casing are provided, respectively, with horizontal extensions a a one above the other, connected by vertical shafts I00 j and base portions of the casing.

or pins a a upon which are pivotally mounted the lateral wings A A, which form when closed a part of the wall of the casing. These wings have their upper and lower edges rabbeted to engage rabbeted edges of the top The vertical edges of the wings are likewise rabbeted to engage similar rabbeted edges of the vertical webs a a so that when these wings are in closed position, as shown in the drawings,

the casing-walls form a complete circle in cross-section, as if formed of one piece. This is shown in Fig. 5 and Fig. 6. The wings can be swung outward to give access to the interior whenever this is desirable. In order to lock the wings A A rigidlyin their closed positions, we provide each of said wings at the end opposite the hinge with a stud or projection a, and we provide the adjacent vertical web a with pivoted locking-levers a a having locking-recesses to fit over said studs (1 and hold the wings rigidly in place. We do not, however, limit ourselves to this particular form of locking device.

The casing A is provided about midway of its height with an inwardly-extending annular flange a above which the casing is provided with a series of breaker teeth or ribs a, said ribs extending at intervals all the way around the interior of the casing. We prefer to form these ribs of different lengths, as is usual in such cases, a portion of the ribs extending substantially the entire distance from the flange a to the top of the casing and others extending upward only a'portion of the distance. Each of said ribsis so formed that its radial depth decreases from its top toward its bottom, as shown in Fig. 2.

The annular flange a is provided at two opposite points with apertures a, (see Fig. 5,) said apertures being formed in this instance adjacent to the vertical webs a a each of which is provided with an aperture com municating with the interior of the casing and in line with its respectively adjacent aperture a and each of said webs is provided with a bracket-lug a, (see Fig. 3,) the upper edge of which is in line with the lower edge of the said aperture in the web. In each of said apertures in the webs is fitted a slide or horizontal plate 0, the upper face of which is flush 'with the upper face of the annular flange a Each of said slides C is provided with a slot c, and a bolt 0 extends through said slot and through the bracket-lug a Said bolt is provided with a wing-nut 0 serving to clamp the slide.- By loosening the wing-nut the slide can be pushed in or drawn out, and thus made to partially or wholly 'close the aperture a formed by the cutting away of flange a These slides C 0 will be adjusted so as to regu late the apertures 01, and thus control the feed of the machine, as will be hereinafter fu rther pointed out.

The lower portion of the casing A is provided with an upwardly-extending cylindrical hollow boss D, preferably formed integrally therewith, and provided at its upper and lower ends with ball-races b and e, respectively. The revoluble cone B has a cylindrical recess in its lower part to fit down over the boss D, and the upper end of said recess is provided with a ball-race b, and balls d are inserted between the races 1) and b, as shown.

. B represents the driving-shaft of the cone. This shaft is rigidly secured to the upper portion of the cone in this instance by having a shoulder abutting against theupper end of the recess in the cone and a nut clamped rigidly upon the upper end of the shaft B, which is threaded for the purpose. The parts may also be keyed or otherwise secured together, if desired. The shaft B extends downward through the hollow boss D and is provided at its lower end with a worm-wheel E, said wheel being furnished with a ballrace e, balls (1 being inserted between the i said ball-race e and the ball-race e at the lower end of the boss D. The worm-wheel E is preferably secured to the shaft 13 by means of a spline, so as to be capable of slight vertical movement thereon, and the lower end of said shaft is threaded and provided with adjusting and securing nuts, as shown, in order to take up wear in the bearings whenever necessary.

The rotatable cone B is provided with a series of breaker teeth or webs 17 These ro-' tary breaker-teeth and the stationary breakerteeth a are so constructed that they have their greatest clearance at the top and their smallest clearance at the bottom, which latter clearance is about one-half inch. The

lower ends of certain of the breaker-teeth b of the cone (or the lower ends of all of said teeth) are provided with radial projections, which we term' sweeps b since their function is to sweep or carry the crushed material around upon the horizontal flange a until it drops through one or the other of the adjustable apertures a in said flange.

Below the flange a we provide what We term the secondary grinding and positive feeding devices. These devices consist of two grinding-rings F and G, the former secured to the casing and the latter secured to the cone in the same horizontal plane. The ring F is provided With a series of inclined teeth or serrations f, and the ring G'is provided with a similar series of teeth or serrations g, inclined in the opposite direction from those of the ring F, the construction being such that when the cone is revolved the teeth of the two rings will have a shearing action and at the same time a downward positive feeding action, as is illustrated diagrammatically in Fig. 7. The teeth f and g are also of greater depth at their upper ends than at their lower ends, so that the spaces or notches in the grinding-rings and between the said teeth decrease in depth from top to bottom, and thus positively prevent any particles falling through between the grindingrings F and G until said particles have been reduced to a certain definite degree of fineness. This construction enables us to effect a fine reduction, and at the same time the downward-shearing action of the opposing teeth of the two grinding-rings produces a positive feed of the material whether dry or wet, so that there can be no clogging of the machine.

Below the grinding-rings F and G the casing is provided with an annular space (0 and the base of the casing is provided with a vertical aperture a, communicating at its upper end with the annular space a and forming a discharge-channel through which the ground material can be discharged.

The cone Bis provided below the grindingrings F and G with a series of radial sweeps 1), preferably formed integrally with a ring 12 secured to the cone by means of bolts, as shown, said sweeps being arranged to rotate in the annular space 61 just referred to, and conduct the material to the discharge-channel a, through which it drops.

The lower part of the casing is provided with a worm-shaft H, having a worm H thereon engaging the worm-wheel E, and said shaft ticles which then fall upon the horizontal flange a of the outer casing. These particles are then carried around by the sweeps b of the cone until they are brought over one or the other of the regulated apertures a in said annular flange, whereupon they drop through said apertures to the secondary grinding and positive feeding apparatus below. Here the crushed particles are further-ground between the teeth of the opposed grindingrings F and G, as before described, until reduced substantially to the fineness of coarse salt or granulated sugar, after which the ma terial is discharged through the channel a by means of the sweeps Z1, as before described. The action of the machine is very rapid and on account of its positive feeding action, as described in connection with the rings F and G, it is enabled to grind and discharge a very large quantity of material. Since the opposed sets of teeth in either the breaking or grinding apparatus serve to reduce the material by'mutual and reciprocal action, each set of teeth affordingat once a crushing force upon the material and a resistance to the crushing force of its opposed set, the opposed sets of teeth jointly may be called reciprocal sets, and either of the opposed sets may be termed the reciprocal of the other. Likewise the two principal parts or main members of the entire breaking and grinding mechanismto wit, the revoluble and grinding machine proper is preferably supported upon a pulverizing-chamber K, as shown in Fig. 8. From the channel (1 the ground fuel falls into the vertical projecting trough a, mounted on the end of the pulverizing-chamber K. The trough a conveys the said fuel to the aperture (1 through which it passes into the pulverizing-chamher. This pulverizing-chamber has its main body formed substantially in the shape of a barrel, being circular in cross-section and of greater diameter in the center of its length than at the extremities. The interior surface of the casing K is preferably serrated or roughened, forming minute spaces between said serrations, in which the material can lodge. The material thus lodged protects the inner surface of the pulverizing-chamher from the abrasive action of the rotating coal and also presents an abrasive surface which facilitates further pulverization.

The casing K is provided with a central shaft L, extending through the same and provided with a series of radial arms m, each carrying at its outer end an adjustable blade M, secured to the arm by a set-screw m or other fastening device, said blades being adjustable radially and also upon their central axes.

At one end of the pulverizing chamber or casing and communicating therewith is an annular trough N, provided with a tangential discharge-aperture, which is connected by suitab e means with the furnace. Said discharge-aperture and furnace connection are not shown. The shaftLis provided with a series of ejector-blades 0 within the said annular trough for the purpose of creating a blast through the pulverizing-chamber to withdraw the aerated coal therefrom into said trough N and to eject the mixture through the discharge-aperture and f urnace:

connection aforesaid into the furnace.

Reduction by direct action such as takes place in positive breakers and grinders is generally recognized to be much more efficient than the indirect action of attrition. Therefore, in the class of automatic stokers defined hereinbefore it is desirable to reduce the fuel to as fine a degree as practicable in the preliminary breaking or grinding appa ratus and before delivery to the pulverizing apparatus. This is also desirable, because the time as well as the work required to pulverize the coal in the pulverizing apparatus is proportional to the average size of the coal fed to it,and the output capacity of the pulverizer varies inversely as the size of the coal which it receives from the preliminary reducer. Heretofore the degree of reduction attainable in practice in the preliminary positive reducing apparatus has been limited by the following conditions, to wit: positive disintegrating apparatus when adapted to reduce the coal to a very fine degree must also be designed in such manner as to exert upon the coal in course of reduction a positive feeding or conveying action in order to overcome the tendency to congestion of the coal in the apparatus, particularly when in a wet condition. Heretofore this positive feeding or conveying action of the preliminary positive reducer, and hence the fine degree of reduction attainable only in conjunction with such a feeding or conveying action, has been prohibited by reason of the difficulty of regulating the amount of fuel delivered by the same, such regulation being necessary in order to conform to the varying demand of the furnace. The forcing action of a positive feeding reducer such, as referred to precludes the regulation of its output at the point of delivery, while the coal at the intake is not sufficiently fine or uniform in grade to permit of an even regulation at that point. It is possible to regulate the output of such positive feeding-reducers by variable-speed devices controlling the speed at which they are driven; but this means has not been found reliable nor sufficiently compact and flexible to be practicable.

In our improved form of disintegrator as embodied in a preliminary positive breaking and grinding apparatus for use in connection with the class of automatic stokers defined hereinbefore the fuel in its commercial form not being sufficiently fine to be controlled by feed-regulating devices is fed into the casing inclosing the initial breaker in such quantities and at such intervals as will prevent the entire running out of the fuel meantime undergoing preliminary reduction by the initial breaker. The spaces between the adjacent initial breaking and crushing ribs on either the cone or casing and the clearance between .the opposed reciprocal sets of these ribs are amount of fuel delivered by the secondary grinder is uniformly controlled and regulated by controlling the amount received at its in take We have combined in our improved form of preliminary reducing apparatus the characteristic advantages of both the positive feeding type of reducer and the gravity feeding typeto wit, respectively, fine degree of reduction without liability to clogging and controllability of output.

In the following claims we have employed the term a condition of substantially uniform fineness to designate the condition of the fuel as it leaves the secondary grinder. By this language is meant simply that the material is reduced to substantially the condition of meal, wherein the particles are more or less nearly the same size, in contradistinc- 'tion to its condition on leaving the initial breaking mechanism, Where some particles will necessarily be of considerable size, while other particles are extremely minute. This distinction results of necessity from the difference in the operations of breaking andof grinding.

What we claim, and desire to secure by LettersPatent, is-

1. In apparatus for preparing fuel and feeding it in a finely-divided condition to a furnace, the combination with initial breaking me'chanism,of secondary grinding mechanism receiving the fuel therefrom and adapted to reduce it to a condition of substantially uniform fineness, a pulverizing mechanism receiving the fuel from the secondary grinding mechanism and provided with rotary pulverizing-blades adapted to further reduce the fuel, and an injecting mechanism for delivering the pulverized fuel to the furnace, whereby the Work of the pulverizing mechanism and the power required for operating the apparatus is greatly reduced, substantially as described.

2. In an apparatus for preparing fuel and feeding it in a finely-divided condition to a furnace, the combination with an initial breaking mechanism, of a secondary grinding mechanism receiving the fuel therefrom and adapted to reduce it to a condition of substantially uniform fineness, said mechanism ineluding reciprocal devices provided with means for positively feeding the fuel, a pulverizing mechanism provided with rotary pulverizing-blades,receiving the fuel from the secondary grinding mechanism and adapted to further reduce it, and an injecting mechanism receiving the material from the pulverizing mechanism and adapted to feed it to the furnace, whereby the work of the pulverizing mechanism and the power required to operate the entire apparatus is greatly reduced and whereby the uniform feeding of the injecting mechanism is insured, substantially as described.

3. In an apparatus for preparing fuel and feeding it in a finely-divided condition to a furnace, the combination with initial breaking mechanism, ofa secondarygrinding mechanism receiving the fuel therefrom and adapted to reduce it to a condition of substantially uniform fineness, injecting mechanism for feeding the fine fuel to a furnace, and a feedregulating mechanism interposed between the initial breaking mechanism and the secondary grinding mechanism, for regulating the quantity of fuel delivered to the furnace by the injecting mechanism, substantially as described.

4. In an apparatus for preparing fuel and feeding it in a finely-divided condition to a furnace, the combination with initial breaking mechanism, of secondary grinding mechanism receiving the fuel therefrom and provided with reciprocal devices for producing a positive feed, for reducing the fuel to a condition of substantially uniform fineness and positively feeding it, and injecting mechanism for feeding the fine fuel to a furnace, whereby the feed of the fuel by said injecting mechanism is rendered uniform by the positive feed of the secondary grinding mechanism, substantially as described.

5. In apparatus for preparing fuel and feeding it in a finely-divided condition to a furnace, the combination with initial breaking mechanism, of secondary grinding mechanism receiving the fuel therefrom and adapted to reduce it to a condition of substantially uniform fineness and provided with reciprocal devices for positively feeding it, injecting mechanism for feeding the fine fuel to a furnace, and a feed-regulating mechanism interposed between the initial breaking mechanism and the secondary grinding mechanism, whereby the quantity delivered by the injecting mechanism can be regulated and the positive uniform feeding of such regulated quantity is insured, substantially as described.

6. In apparatus for preparing fuel and feeding it in a finely-divided condition to a furnace, the combination with an initial breaking mechanism, of a secondary grinding mechanism receivingthe fuel therefrom and adapted to reduce it to a condition of substantially uniform fineness, a pulverizing mechanism for still further reducing the fuel, an injecting mechanism for feeding the pulverized material to the furnace, and a feed-regulating mechanism interposed between the initial breaking mechanism and the secondary grinding mechanism, for regulating the quantity of fuel delivered by the injecting mechanism, substantially as described.

7. In apparatus for preparing fuel and feeding it in a finely-divided condition to a furnace, the combination with initial breaking mechanism, of secondary grinding mechanism reeeiving the fuel therefrom and adapted to reduce it to a condition of substantially uniform fineness, and provided with reciprocal devices for producing a positive feed of the material, a pulverizing mechanism recei ving the material from the secondary grinding mechanism, and adapted to further reduce it, an injecting mechanism for delivering the fine fuel from the pulverizing mechanism to the furnace, and a feed-regulating mechanism, interposed between the initial breaking mechanism and the secondary grinding mechanism for regulating the feed of the fuel by the injecting mechanism, whereby the uniform and positive feed of the regulated quantity of fuel, by the injecting mechanism is insured, substantially as described.

8. In an apparatus for preparing fuel and feeding it in a finely-divided condition to a furnace, the combination of a casing and a revoluble member located within the same, said parts being provided with reciprocal initial breaking mechanism, and with reciprocal secondary grinding mechanism below the same adapted to reduce the fuel to a condition of substantially uniform fineness, a horizontal flange secured to one of said parts interposed between the initial breaking and the secondary grinding mechanisms, and provided with feeding apertures, adjustable slides for regulating the size of said apertures, sweeps secured to the other of said parts, and extending over said flange, and injecting mechanism for delivering the finelydivided fuel to a furnace, whereby the quantity delivered by said injector is regulated by said slides, substantially as described.

9. In an apparatus for preparing fuel, and feeding it in a finely-divided condition to a furnace, the combination of a casing and a member revolubly mounted therein, said parts being provided with reciprocal initial breaking mechanism, and reciprocal grinding mechanism below said breaking mechanism for reducing the broken material to a condition of substantially uniform fineness, said grinding mechanism including reciprocal parts disposed angularly with respect'to each other adapted to positively feed the ground fuel, a horizontal flange secured to one of said parts, interposed between the initial breaking and the secondary grinding mechanisms,and provided with feeding-apertures, adjustable slides for regulating the size of said apertures, a pulverizing-chamber below said secondary grinding mechanism, receiving the fuel therefrom and adapted to further reduce it and an injecting mechanism for feeding the pulverized material to a furnace, substantially as described.

10. In an apparatus for'preparing fuel and feeding it in a finely-divided condition to a furnace, the combination of a casing and a revoluble cone mounted therein, said parts being provided with reciprocal initial breaking devices, and with reciprocal secondary grinding devices, below the same, said secondary reciprocal grinding devices having portions disposed angularly with respect to each other adapted to positively feed the fuel downward, a horizontal flange secured to said casing between the initial breaking and secondary grinding devices, and provided with discharge-apertures therein, adjustable slides for regulating the size of said apertures, a series of sweeps on said cone, extending over said flange, for conveying the broken material to said apertures, said casing being provided with a horizontal surface below said secondary grinding devices, having a discharge-aperture therein, sweeps secured to said cone extending over said horizontal surface, a pulverizing mechanism receiving the fuel from said discharge-aperture and injecting mechanism receiving said fuel from the pulverizing mechanism and delivering it to :a furnace, whereby the feed of said injecting mechanism is regulated by the said feed regulating slides, and the uniform feed of such regulated quantity of fuel is insured, substantially as described.

11. In apparatus for preparing fuel and feeding it in a finely-divided condition to a furnace, the combination of the casing and a cone revolubly mounted therein, said parts being provided with reciprocal initial breaking mechanism, and with reciprocal secondary grinding mechanism below the same, for reducing the material to a condition of substantially uniform fineness, said casing being provided with removable lateral portions provided on their inner faces, with devices forming part of the said breaking and grinding mechanisms, when said removable portions are in operative position,'and injecting mechanism for delivering the finely-divided fuel to a furnace, substantially as described.

12. In apparatus-for preparing fuel and feeding it in a finely-divided condition to a furnace, the combination of the casing and a cone revolubly mounted therein, said parts being provided with reciprocal initial breaking mechanism, and with reciprocal secondary grinding mechanism below the same, for reducing the material to a condition of substantially uniform fineness, feed-regulating mechanism interposed between the said breaking and grinding mechanisms, said casfurnace, the combination with initial breaking mechanism, of secondary grinding mechanism located below the same, and provided with reciprocal parts disposed angularly with respect to each other reciprocal parts adapted to positively feed the material, and a feedregulating mechanism interposed between the initial breaking mechanism and the secondary grinding mechanism whereby the quantity delivered by the secondary grinding mechanism can be regulated and the positive feed of such regulated quantity insured, and injecting mechanism for delivering the finelydivided fuel to a furnace, substantially as described.

In testimony whereof we affix our signatu res in the presence of two witnesses.

Witnesses:

EDWARD C. ANLA, WILLIAM J. SMITH.

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