US337370A - Middlings-purifier - Google Patents

Description

(No Model.)

E.T'.BUTLER. MIDDLINGS PURIFIER.

Patented Mar. 9, 1886.

Witnesses Fig'. 1

Irnventot` ,I Sub.

Attorney N, linens. mmuumnpnnr. wumngw", D, c

NITED STATES PATENT OFFICE.

ELI T. BUTLER, OF PHILADELPHIA, PENNSYLVANIA.

IVIIDDLINGS-PURIFIER.

v51EECIIEFICA'JTION forming part of Letters Patent No. 337,370, dated March 9. 1886.

Application filed July 13, 1885. Serial No. 171.514. (No model.)

.To all wwm it may concern:

Beit known that I, ELI T. BUTLER, of Philadelphia, Philadelphia county, Pennsylvania, have invented certain new and useful Improvements in Middlings-Purifiers, of which the following is a specification.

This invention pertains to machinery for purifying middlings. Middlings have usually beeny purified in machinery involving screens or sieves whose mesh was smaller than the coarsest of the material fed to them, the sievesperformingaveritablesiftingfunctionthat is, permitting the small matter to pass through and retaining the large matter. So far as the sieves were concerned, their oilice was to effect a separation on a basis of size of material presented. Their operation was modified and supplemented by the action of currents of air passing through them, and the clogging ofthe sieves, due to the reception of material larger than the mesh, was sought to be overcome by the use of brushes. In my machinery I make use of screens, but they do not perform the usual office of sieves, inasmuch as they vreceive no material not capable of passing through them. In my machinery the sieves perform the office of aerial suspenders-that is, they serve to suspend thematter while it is acted upon by air-blasts. The separation effected by the sieves is a separation due to the difference in gravity ofthe particles,

rather than to a differencein the size of particles. I cause currents of air to pass horizontally between two vibrating screens the mesh of which is coarse enough to permit thepassage through them of the largest material fed to the screen.

My invention will be readily understood from the following description, taken in connection with the accompanying drawings, in which- Figure 1 is a vertical longitudinal section of my improved purifier, the section being taken upon line b of Fig. 2, and the direction of View the bolting-reel from which the middlingspurifier receives its supply of middlings, this reel being supplied with a proper grade of cloth in the usual manner; B, the casing of the purifier, the same being in simple box form, as usual in this class of machines; C, a screen-holding frame disposed horizontally within the casing; D, the hangers by which this screen-frame is suspended in the casing; E, the usual eccentric by which the shaking motion is given to the screen-frame; F, three parallel screens carried by the screenframe, and formed of gauze two to twelve grades coarser than the gauze of the primary screen A; G, ahorizontalair-conduitunder the roofof the casing; H, an adjustable admission-gate, placing the conduit G in communication with the horizontal screen at the head of the machine; J, a similarly-arranged gate at the tail of the machine; K, asuction-fan arranged to draw air through the gates from above the shaking screens; L, air-inlets at the head of the screenfr'ame, between the screens; M, an air-inlet to the case ofthe machine at its head, below the screens; N, a chamber for receiving the clean middlings; O, aout-off chamber for receiving middlings less cleaned than that received by the chamber M; P. the tailings-chamber; Q, a pivoted adjustable partition between the chambers N and O. by means of which the cut-off chamber may be caused to receive the earlier or later discharges from the screens; R, the feed-hopper of the puritier, and S angular crossfpartitions at the head of the machine, over the screens arranged to deliver the middlings as received at the head of the upper screen.

-fThe middlings fall upon the head of the upper screen, and, owing to the'large mesh of the gauze,would naturally fall directly through the gauze, there being no overloading of the screen. The direct passage of the middlings through the upper gauze is retarded by the upward currents of air through the gauze. As a consequence of this retardation, most of the middlings will advance along thevupper screen toward the tail. During this advance the middlings on the upper screen Will be subjected to the upward currents of air passing through the screen, and the fluffy matter will be carried up and out of the machine by the fan. As the middlings become cleaner, they become less susceptible to the retarding action of the upward 'air-currents, and they con= sequently fallthrough the upper screen onto IOO the middle one. On this screen the middlings are again subjected to the action of the upward air-currents, and the middlings passing through this screen onto the lowerone become again subjected to the action of these currents. The cleanest of the middlings will find its way quickly downward through all of the screens into the chamber N before these middlngs have had an opportunity to advance far -toward the tail of the machine. Those middlings which are less clean will be capable of a further advance toward the tail before they can get through the screen, and these middlings will find their way to the chamber O. The tailings will have passed the entire length of the screens before they can have passed through the three screens, and they consequently fall off into the chamber P. The partition Q is to be so set in relation to the head ofthe screen that the two chambers N and O will receive their proper grades of middlings, and all of the lower chambers may be supplied with outlet spouts or conveyers, as is usual.

The advance of the middlings along the screens would naturally be governed by the rate of retardation to their passing downward through the screens, this rate of retardation being fixed by the strength of the aircurrents. The gates H and J provide for regulating the direction of the air-currents as well as the strength of these currents. If the gate H be Widely opened, and the gate. J correspondingly closed, the direction of the air-currents will be almost directly through thehead of thescreen, while if the degree of opening of the two gates be reversed the directions of the air-currents will be toward the tail of the machine as well as upward. By proper adjustment of these gates the intensity of the longitudinal currents may be regulated, so as to cause these currents to move the material toward the tail of the screen at any rate desired, whereby the time of their subject-ion to the purifying action is brought under perfect control.

It will be readily understood that there may be as many of the screens F as are desired, so long as there are two of them; butin practice three screens, as shown, will be found'preferable to a greater or less number.

vI deem it proper to state that my improved purifier involves the employment of a number of old and Well-known devices, to which 'I lay no claim, my improvement being intended to overcome recognized defects in the old devices as heretofore arranged and employed. Thus to arrange several sieves of silk cloth, wirecloth, or screen-iron in a single shaking frame, and to allow the material to fall from one to the other, is not at all new; but in these multiple sieves the grade of the lower sieves has been made successively finer, the sole object being that mattertoo coarse Vto pass through the upper sieve would pass over the tail of that sieve, while matter passing through that sieve would again be graded and separatedby the following finer sieves, and so on, each sieve in its' turn delivering over its tail a grade of material coarser than its sieve, but ner than the sieve above, at the same time delivering through its mesh a material finer than its mesh, to be further graded by the lower sieves. In my device the individual sieves are all coarser than the material which falls upon them, and they therefore do not exercise a grading eiect upon the material by reason of the relation of the size of mesh to size of material. The old multiplescreens referred to have sometimes been arranged with individual screens, one over the other, and, again, with individual screens succeeding each other endwise, the screens all being in asingle shaking frame; but in all cases each screen vhas been arranged to receive its material from a precedingscreen of eoarser mesh, the entire system being based upon gradation of material by the gradation of mesh of sieve. In my machine I obtain diii'erent grades of material from one grade of sieve-mesh.

' To cause an upward current of air to pass through the sieves, so as to hold the material,

as vit were, in suspension over the sieves, and

to blowthe iluHy matter from the `suspended material, is old and very commonly employed in middlings -puriiiers and other analogous separatingmachines, I employ this well- (known air-blast system in connection with a multiple sieve whose mesh is coarser than any of the, material received by it, the air-b1ast serving, as of old, to suspend the material, but also to advance the material toward the tail of the sieves, whereby the material is floated in an open manner for a greater or less time over a sieve whose mesh is coarser than the material, the ability of the heavier materials to pass through the coarse sieves in spite of the lifting effect of the blast being utilized in eii'ecting the work of purification and the gradation of neness of matter not drawn ofi' by the air-current.

To deliver material upon the sieve whose mesh is coarser than the material is not new, the plan beingvfully set forth in United States VLetters Patent No. 311,808, granted to myself and another party on February 3, 1885. The `material was received upon a single vibrating sieve whose mesh was coarser thanthe material, and an upward current of air kept the material more or lessjn suspension; but it was found that the material would pass through the sieve improperly purified, even when the sieve 'had such a fine mesh as to greatly interfere with the rapidity of the purifying process. We sought to overcome this difficulty by pasting strips of cloth to the sieve, thus producing a sieve part solid and part sieve-like, the in tention being that the material passing tail ward over the sieve should not at all timeshave an opportunity of dropping from thesieve, its opportunity for dropping being restricted to the open Aportions between the strips. Even with this modification the machine has not been at all satisfactory, besides bei-ngfcumbersome and expensive, and of very limited IOO capacity when compared With my improved machine.

I claim as my invention- In a purifier, the combination, with a pri- 5 mary screen adapted to deliver material to the purier, of a shaker constructed with parallel screens, one above another, and of a mesh coarser than that of said primary screen, and with air-inlets between the heads of ther 1o screen, a hopper delivering from the primary Screen tothe head of the upper shaking screen,

an inclosing casing having air-inlets below the screens and adjustable air-exits above the opposite ends of the upper shaking screen, and means for producing suction at said adjustable 15 air-exits, substantially as and for the purpose set forth.

ELI T. BUTLER.

NVitnesses:

THoMAs EvANs, ALEXANDER RICKEY.

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