US2353346A - Hopper nozzle - Google Patents

Description

Ju1y11, 1944. H. H. Lo'GA-N 2,353,346

HOPFER NOZ ZLE Filed Dec. 7, 1959 Patented July 11, 1944 n 2,353,31165 l HOPPER NozzLn i Henry H. Logan, Chicago, lll.,A assignor'to'"Logan` Engineering Co., Chicago;y Ill.,afcorporation: of

' Illinois Application December 7, 19.39, Serial No.3il8,l )15 l of time until the stoppage is relieved. The prac-` 1o claims.

My invention relates to hopper nozzles, `that is, compressed iluid` nozzles to be placed in the hopperv bottoms of bins, railway cars, and the like, to promote iiow and especially to relieve the jamming or stoppage occasioned by arching.

One object of my invention is-to produce a more effective action for a given size of nozzle and a given supply of compressed air therefor. This objective I attain by an arrangement and placement of the nozzle which better utilizes not only the direction given the emergingrair stream, but also the expansive forces of the emerging air` stream. i f l A l -Another `object of my invention" is anozzle which' may be placed atwiseupon the inner surface of the hopper, as distinguished from being recessed thereinto, and which still, does not substantially impede the flow of the material nor catch the material. `Such a superciallyapplied nozzle is more convenient of application to both new and existing hoppers. l

Another andf related object is a nozzle in vthe form `of a single unit which, aside from its anchoring bolts'orscrews and its feedrpipe, is a single pieceand which, being a separate unit in itself, can be -applied along with like nozzles in whatever 'number and arrangement theparticu-4 lar circumstances require. This aiords a greater fiexibility and universality of application than Withvhopper nozzles which are preformed in fixed gang's. With my nozzles, it is a relatively simple matter to add additional nozzles or to change4 the locations of nozzles already installed. This facilitates the determination, by actual experiment under working conditions in any given hop-v per,`of the optimum placement and arrangement of the nozzles, together witha minimum number of nozzles. v i -v f A further object is the improved provision fora quick momentary gang operation of thenozzles for breaking any stoppage or jamming due to arching or the like. An auxiliary object in this connection is a provision for such a momentary gang operation of the nozzles, wherein a relatively large quantity of compressed air is used in a short time, but still permitting the `economical use of a small size feed pipe line fromla distant source of compressed air. This -is important because the compressor and storage tank for the compressed air supplydn an industrial plant are frequently located a great distance from the hoppers.

Quick acting and elicient hopper nozzles are much to be desired in industrial plants. A stoptioe of pounding on hopper walls shortens the life of the hopper. V.Reaching up from beneath withf a pole is dangerous `because of the likelihood of a sudden avalanche-of` `material when the arching is successfully broken, before the workman can get away. The practice of workingwith a pole from the top of the bin is also dangerous because of choking from the dust and the danger of. be-3 ing smothered, should the workman accidentally drop to the bottom rof the hopper. -In Aeither case, the bin or the bottom of thedischarge passage has to be opened up for manual access and this often releases objectionable dusts which norav mally are coniined by covers for vthe bin and enclosed canvaspr rigid conduits leading from the discharge Vend of the hopper. With my hopper nozzles the nozzles are actuated and thestoppage relieved without the necessity of openingupany doors vor` passagewaysthrough which objectionfv able dust might be exhausted. f I

The foregoing,otogether with further objects,

features and advantages of my invention, are set. forthin the following description of 'a specific" embodiment thereof` and illustrated inV the accompanying drawing, wherein:`

Fig. 1 Yis a conventionalized vertical cross-section of abin with a battery of my nozzles installedv in its hopper bottom, together with a somewhat diagrammatical layoutofthe air supplyvsystem` thereto; l

Fig. 2.is a frontface elevation ofl yohneofvthez considered as taken onthe takenyon the line 3 3 of Eig. 2 or Fig.`1; l

. Fig. '4 is agsection] of thenozzle takenlon the line 4-4 vof Fig. -3', .inf alplane parallel with the wall Vof-the hopperj Fig. 5 is atop viewfof the nozzle;

Fig. 6 'sabottom view of the nozzle, and

Fig,V ,'Z is an intermediate horizontal.section,

taken on the line .1f-.l of Fig. 4..

Y the hopper .walls I have shown mounted a. set .of

page of material in the hopper represents a loss 5g;

my nozzles I2. The number` and arrangement of` the nozzles will depend upon thesize, slope and other characteristics of the hopper and also-to a certain extent `on,tina-nature of thematerial` being; handled and the pressuret of,i thexairznsupe plv available .Espeially ist the larg?? Sizes. Qf

transverse ,cross-section,

. y lo with4 a hopperl I, atthebottom having a, correspond-- hoppers it is usually desirable to arrange the nozzles on each hopper wall in a quincunx pattern, that is, a staggered arrangement in parallel horizontal rows with the nozzles in even number rows offset from those in odd number rows. Each nozzle I2 is fed by a pipe stem I3 extending through the wall of the hopper and the pipe stems I3 are connected without the Wall` to manifolds III branching from. a delivery pipe I5 leading from a compressed air receiver I6.

Each nozzle I2 is nat on its back side and its back side is placed against the at inside face of the hopper wall Il as shown in Fig. 3. The y nozzle is preferably a one-piece casting streamlined and bulfed on its exposedsurface to present a minimum resistance to the 110W of material thereover. It is attached to the hopper wall by a pair of fastening elements I'I', one at the top and one at the bottom, extending through suitably located holes. The fastening elements are preferably of a headed variety such as wood screws, expansion bolts, or bolts and nuts, clepending largely on whether the material of the hopperV wall be wood, concrete, sheet metal, or cast iron. In order to avoid obstructionv to free sliding thereby of the material within the hop'- per, the hea-ds of the fastening elements are countersunk into the outer face of the nozzle body Within counterbores recessedv in such face at the holes for the elements. A hole is drilled through the hopper wall for passage of the feed stem I 2,v as shownl in-Fig. 3;

The nozzle is preferably segment-shaped, with its apex pointing upwardly. The nozzle has a nat hollow interior I8 formed by a flat back plate I9 and a slightly rounded or arched face plate 20. 'I'he face plate 20 isY joined to the back plate I9 at the apex and along the diverging lateral margins,- but at the bottom is not connected, leaving a narrow discharge opening 2-I, as best seen in Fig. 6. The lower screw or bolt I1 passes through Aan ear 2 2 at thek bottom of the back plate. Y

The back plate I9I is provided with a boss 23 tapped to receivel the` end of the feed pipe stem I3 and of suflicient thickness to'provide adequate anchorage for a threaded end of the pipe stem. The face plate in the" longitudinal cross-section of Fig. 3 isr curved or bulgedoutwardly, with the greatest bulge opposite the feed stem I3. This affords substantial air passage for air issu-A ingy from vthe stem` I3, despite theadditional thickness of the boss 23 at this region. K

At the lower end of the nozzle the face plate 20 is spaced only a short distance from the'back plate I9, whereby the long narrow discharge slot or openingY 21' is formed. To lighten the casting and facilitate coring of the hollow interior I8, aY generous opening 24 may be left in the back'plate I9., as best shown in'Fig. 4'. `Aswill be seen from the several `Grossi-sections and as indicated by the The discharge opening 2|, as shown in Fig. 3, is defined by substantially parallel and closely spaced surfaces extending some distance back or inwardly from the discharge end. This serves to discharge the air in a thin sheet substantially parallel with the hopper wall, but in a diverging fan shape. Thus, if the nozzles are not placed too far apart laterally, the fan-shaped flat streams of air emerging from the nozzles will combine into a ycontinuous flat sheet of air a short distance below the nozzles.

When a stoppage in the flow of material in the'hopper has been caused by the arching of the material, it-is not always suflicient to clear a centralu passage through the arch. For example, it is well known that an annular arch or Vdome may be self-supporting even though its central portion is removed. To put it another way, a truncated conical wall, although open at the top, may be suiiiciently self-arched to resist collapse from its own weight. It is for this reason that I do not place my nozzles in the center of the hopper, but, instead, along the sides. But even nozzles placed at the sides of the hopper are not always eective if they merely direct jets of air horizontally to the center of the hopper. They may merely form round or cylindrical holes for the jets without entirely breaking the arching. This is in much the same manner that circular windows ,can easily be formed in a truncated arched dome, even though open at its top, without causing its collapse.

The reason that my nozzles are so peculiarly effective is that they discharge the compressed air as at and relatively wide jets parallel with and close tothe walls of the hopper.v Thus, they attack the arch of material at its most vulnerable point-its base or abutment. Butl the air jets from my nozzles do more than take matesurface shading in Figs. 2 and 5, the exposed exterior of the nozzle' and especially those portions of the exposedV surface whichl in, Whole or in part face upwardly, are carefully rstreamlined with al view to" reducingk the resistance to ow'of material over the nozzle, rand no abrupt upfacing shoulders are 'lftf'which might catch the material ror impede its flow. In general, theV nozzle is very flat and thin'toredu resistance toilowof material. K Y

Compressedair enteringtheinozzle through the feed stem I3K`passes" downwardly through'the hcllowinterior passagei'which, as best shown in Fig.4, diverges downwardly in al fan Shaperial awayfrom the base or abutment of the arch, which could merely let it drop down farther toward the bottom opening of the hopper.

The air in' the flat jets is compressed air of, say, pounds per square nchwhen it enters the nozzle. As it emerges from the nozzle its pressure decreases somewhat due in part to the divergence of the jet. But still the air in the jet is relatively highly compressed and, being compressed, it presses in all directions including, most importantly, yfan inward expansion; that is,"an-' expansion away from the adjacent Xed wall of the hopper. at 90 pounds pressure per square inch will, after it has emerged into the fan-shaped thin jet, even some distance below the nozzle, exert hundreds of pounds of inward pressure against each square foot of the base or abutment of the arch, fore-- ing the material into the center where it quickly collapses. Y

In this way my nozzles achieve'unusually effective and quick collapsing of the arching 'of' the material by three combined actions: First, the air jets carry or eat away the material at the base of the arch where it abuts the sides of the hopper. Second, the compressed air is insertedas a laterally expanding flat sheet of com` pressed air between the sides oi the hopper and the arched material, with the result that the arched material is pushed in toward the ycenter under`V tremendous pressure which it cannot re-l sist. Third, lthe general direction of the air jets being downward, the material of the collapsed:

Compressed air entering the nozzle' instantaneous actuation of the nozzles. Other- Wise', in a Very brief or momentary actuation of the nozzles, although the nozzles might collapse the arch, the material of the collapsed arch might reform itself into an arch after the actuation of the nozzles was terminated and before that part of the material which had caused the arching had been discharged from the hopper. This latter point is of especial importance in those instances where the arching has been caused by an unusual moisture content in a certain portion or stratum of the material in the bin or where the material is of a character which, once having been compressed under the head pressure on an arch, is more apt to re-arch.

The film of compressed air introduced along the hopper wall and between it and the mass of material servesl as what might be termed a pneumatic lubricant to facilitate a relatively frictionless flow of material down the wall. a.

My nozzle, in its preferred embodiment,` is thus characterized by its external ilatwise application to the inside surface of the hopper wall; its streamlined fiatness; the minimum resistance it affords to downward passage of material; the

flatness of the emitted air `iet and its parallelism with the wall; the downward divergence of the flat air jet; the inward expansive force of the compressed air of the flat jet forcing the mate-4 rial inwardly toward the center of the hopper; the general downward impetus given the mate-` rial' by the jet; the separateness of the individual jets with the attendant flexibility of their placement in relation to other jets; and the superficial application of the nozzles to the hoppers.

Referring again to Fig. 1, the supply pipe I5 from the compressed air receiver I6 to the nozzle manifolds I4 is supplied with a solenoid valve 25. The circuit of the solenoid is fed from a power line and controlled by a push button switch 26 conveniently located on or near the hopper. When the attendant first detects a slowing up or stoppage of feed from the hopper, all he need do is press the push button switch 2S. This causes the solenoid valve 25 to open and a charge of compressed air from the receiver I6 will flow through the nozzles to relieve stoppage.

The solenoid valve 25 may have a timing feature such as a dashpot, or the switch 26 may be a timing switch. However, Ind it practicable to dispense with any timing features in the valve or its control and instead to use the limited amount of air in the receiver I6 automatically to terminate the nozzle action even if the switch 26 be left closed too long.

In this connection I call attention to another advantage in the use of the receiver I6 which is preferably located not far from the hopper. The receiver I6 is fed by a long feed pipe 2'I from a main compressed air supply tank 28 charged by a compressor 29. In the usual plant installation the hopper may be hundreds or thousands of feet away from the main supply tank 28. In that case the feed line 21 running to the receiver I6 may be of very small diameter and therefore economical. This is possible because the nozzles are actuated only infrequently and the feed pipe 2'I, although very small, has on the average a long interval during which it may recharge the receiver I6. On the other hand, the supply pipe I5 leading from the receiver I 6 to the manifolds I4 may be an amply large pipe and, being relatively short, it does not involve much piping expense. If the local reservoir IG'Was not'employed it would be necessary to run alar'ge pipe such as I5 all of the long distance from 4the hopper to the main supply tank 28. 1

While I have `described and illustrated this specific embodiment of my invention', I contemplate that `many changes and substitutions mayk be made without departing from the scope and spirit thereof.

I claim:

1. `'A hopper nozzlel for superficial application to the inside surface of a hopper wall, comprising a thin flat segment-shaped body having a iiat back to lie'against the hopper wall, a front streamlineddownwardly from the apex of the segment to minimize resistance to downward ow of materialalongthe' surface of the wall, a flat segment-shaped hollow interior, a thin mouth for the hollow interior extending across the bottom at the lower edges ofthe front and back to discharge a thin fan-shaped4 jet of air downwardly along the surface of the wall, and a passage through the back for bringing compressed air into the hollow interior.

2. In a hopper having a sloping wall for the discharge of granular or powdery material, 'a multiplicity of nozzles according to claim 1 separately mounted superficially upon the inner surface of the wall and arranged in quincunx pattern over a field of the wall with horizontally spaced adjacent nozzles within the fan-shaped jet emitted by a nozzle intermediate vbut rst above `the said spaced nozzles, whereby substan- 5 tially all the area of the wall within said field is covered by the emitted jets.

3. A hopper nozzle for superficial application to the inside surface of a hopper wall, comprising a thin flat segment-shaped body having a flat back wall to lie against the hopper wall, a front wall streamlined downwardly from the apex of the segment to minimize resistance to downward ow of material along the surface of the wall, the front and back walls being joined along their tops and their lateral margins to leave a flat segment-shaped hollow interior between the front and back walls, a thin mouth for the hollow interior extending across the bottom between the lower edges of the front and back walls to discharge a thin fan-shaped jet of air downwardly along the surface of the wall, and a tapped hole through the back wall near the upper end of, and opening into, the hollow interior for receiving the threaded end of a compressed air feed pipe extending through the hopper wall.

4. A hopper nozzle, according to claim 3, wherein a hole passes through the body, adjacent its apex and above the tapped hole and hollow interior, for the passage of a headed threaded member for anchoring the body to the wall, the hole having a head-receiving counter bore recessed into the outer face of the body.

5. A hopper nozzle, according to claim 3, wherein a hole passes through the body, adjacent its apex and above the tapped hole and hollow interior, the back wall has a lip extending below the front wall, and a hole passes through the lip, the holes being adapted for passage of headed threaded members for anchoring the body to the wall and being countersunk to receive the heads of the threaded members.

6. In combination with the downwardly sloping inner surface of a hopper adapted for containing and directing compactible discrete material downwardly toward ajn outlet in the Vhopper, pneumatic flow accelerating means including a pressure fluid nozzle having a generally flattened body open on one face and enclosed on its opposite faceby a thin arched outer wall, and means for connecting said body supercially on the hopper surface in such relation that the underlying portion of the hopper surface closes said open face and cooperates with said nozzle wall to form a chamber for receivingpressure fluid, the lower edge of said body having' a narrow slot-like discharge mouth forV directing downwardly along said hopper surface a generally flat jet of the pressure fluid'- 7. In combination with the sloping wall of a hopper, a pneumatic flow accelerator comprising a set of separate spaced nozzlesl disposed in a uniform staggered pattern and'adapted to be fed with compressed air, eachnozzle having a narrow slot-like port opening close to and parallel with the wall to discharge a thin fan-like sheet of compressed air downwardly parallel to the surface of the wallV between the wall and material that may be on the wall, the relativeV spacing of the nozzles being such that the nozzles lower down on the wall are within the side sweep of the nozzles higher up on the wall so that the respective sheets of compressed air from all of the nozzles in the set combine to form a film of air over the surface of the-wall to pneumati-A cally separate and force the entire body offmaterial inwardly away from the Wall by expansion of the air in the lm. i

8. The method of relieving arching stoppage of material in a hopper which consists in, from time to time when the material arches, distributing a hopper-lining at lm of compressed air along substantially the entire arch-biasing area of a wall of the hopper and between said area and the wall-,opposing surface of the mass of material in the hopper to the substantial exclusion of an inwardly directed mass-tunneling stream of air, and inwardly lifting the materialbythe expansion Yof the film of compressed air reacting against the hopper wall, without substantial pneumatic agitationvof the material.

9. The method of dissipating the arching of material in a hopper which consists in pneumatically lubricating an arch-basing wall of the hopper'by downwardly injecting a film of compressed airl along thewallr ando'ver the archbasing eld thereoiand inwardlylifting the adjoining material by the expansion of the nlm of compressedair between the walland the wallopposing surface of the mass `of material in the hopper. l

y 1G. The method of relieving arching stoppage of material in a hopper which consists in, from time to time when the material arches,rdown wardly distributing a hopper-lining lm of compressed air between the arch-basing area of a wall of the hopper and the hopper-opposing surface of the mass of material therein, to the substantial exclusion of an inwardly directed masstunneling stream of air and of substantial centrifugal agitation of the mass,v and inwardly lifting the material by the expansion of the film. of compressed air reacting against the hopper wall.

HENRY H. LOGAN.

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