US1298558A - Plansifter. - Google Patents

Description

J. PETER.

PLANSIFTER. APPLICATION FILED ocT. al. IaI.

Patented Mar.' 25, 1919.

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J. PETER. PLANSIFTER. APPucAnoN FILED ocT. 3|. 19m.

Patented Mar. 25,1919.

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J. PETER.

PLANSIFTER.

APPLICATION FILED ocr. 3l. IsII.

Patented Mar. 25,1919.

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J. PETER.

PLANSIFTER.

APPLICATION man oc. al, 191s.

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JACOB PETER, OF ZURICH, SVIITZERLAND.

'.PLANSIFTER.

Specification of Letters Patent.

Patented Mar. 25, 1919.

Application led October 31, 1918. Serial No. 260,595.

To all whom it may concern.'

Be .it known that I, JACOB PETER, a citizen of Switzerland, residing at Zurich, Re public of Switzerland, have invented certain new and useful Improvements in Plansifty. ers, of which the following is a specification.

This invention relates to improvements in plansifters with cleaning brushes for the sieves of the kind in which any direction can be imparted to the streams of stock passing through it. This permits of mixing the discharge of the sieves and the products passing through the meshes of the sieves in any desired manner or of discharging the products in an unmixed condition.

The object of this invention is to provide a plansifter of the class referred to comprising a plurality ofvertical passage-ways for the stock arranged inside the circular guiding frames for the brushes of the sieves and extending through all sieves of a. series of sieves, each of said passage-ways bordering on the sifting-channel of each single sieve. The plansifter according to this invention comprises outside the sifting-channel of the single sieves a further series of vertical passage-ways extending through all sieves of the series and also bordering on the sifting-channel of each single sieve. Said inner and outer vertical passage-ways are arranged so that upon a rotation of the single sieves about their. middle axis corresponding to the division into vertical passage-ways, the same passage-ways as before are again obtained.

This invention will now be more particularly described with reference to the accompanying drawings illustrating by way of example several embodiments of the invention. l

In these drawings:

Figure 1 is a cross-section on the line I-I of Fig. 2 through a plansifter comprising sieves arranged according to a first mode of carrying the invention into effect.

Fig. 2 is a cross-section on the line II--II of Fig. 1;

Fig. 3 is a cross-section on the line III-III of Fig. 2 and Fig. 4 a cross-section on the line IV-IV of Fig. 2.

Fig. 5 is a top plan view of a collecting tray of the plansifter sieve as shown in the Figs. 1, 3 and 4 in the three first sieves.

Fig. 6 is a corresponding view of the collecting tray of this plansifter as shown in Figs. 1, 3 and 4 in the three lower sieves.

Fig. 7 is a section on a smaller scale on the line VII-VII of Fig. 1 and Fig. 8 vshows on the same s'fale as Fig. 7 a section on the line VIIIVIII of Fig. 1.

Fig. 9 is a section on the line IX-IX of Fig. l0 through another plansifter according to this invention.

Fig. 10 is a cross-section on the line X-X of Fig. 9;

Fig. 1l is a cross-section on the line XI-XI of Fig. 10.

Figs. 12, 13, 14 and 15 are cross-sections on the lines XII-XIIv and XIII--XIIL XIV-XIV and XV-XV respectively of Fig. 10.

Figs. 16, 17, 18 and 19 illustrate several square sieves provided with sifting-channels differing from the sifting-channels of the sieves shown in Figs. 1-15 and also differing from each other.

Fig. 20 is a top plan view of a circular sieve.

Referring at first to Figs. 1-8, 3 denotes frames for the sieves arranged between a bottoni 1 and a cover 2. Said frames 3 are square and they are provided at their corners with reinforcing members4. The latvter are staggered vertically with regard to the frames 3, in order that the sieves stacked one on the top of the other` may be secured in an accurate manner in their proper position (Figs. 2 and 3). The reinforcing members 4 of the uppermost and lowest frame 3 respectiyely, are so dimensioned that the bottom l and the cover 2 come to lie snugly against the/sieves and the reinforcing members 4 of said frames 3.

5 denotes a circular partition provided in the center of each frame 3. The partition 5 extends over the whole height of the frame 3 and is connected to the latter by means of a transverse reinforcing member 6 arranged with regard to the height of the frame 3 in its middle. The space surrounded by the circular partition 5 is subdivided into four spaces 71 by means of radial partitions 7. In each corner of the square frame 3 is also provided an unobstructed space confined between the two sides of the frame forming the corner and a cross-partition S.

Above the transversal reinforcing member 6 is arranged a collecting tray 10 fixed to ledges 11 (Figs. 3 6). The ledges 11 are arranged on the inner side of the frames 3 along their part-s lying between the partition S and also along the inner side of the latter. Upon lthe Vcollecting trayl v10 rests a double armed brush 12, the arms of which are situated diametrically opposite one another (Fig. 6); said arms are connected to a ring 13 surrounding the partition 5. A

clearance is provided between partition 5 frame 3 of the sieve and to the partitions 8 and 9. The partition 9 extends at one end up tothe frame 3 of the sieve and at the other end in a tangential direction up to the partition 5, the sifting channel having substantially a spiral shape. The space 71 arranged atan angle with regard to the portion of the partition 5 extending up to the partition 7 communicates with the space above the woven screen 14 by means of a slot- 15.4 16 denotespallets which are for mov- .ing the products in the sifting channel.

charge openings 17 denotes a feed or inlet aperture for the stock provided in the cover 2. Between the lowest sieve and the bottom 1 are arranged passages 18 communicating with the dis- 19. branches provided nearthe corners of the sieves. In each partition 8 are mounted two superposed slide-like members 21.

In the plansifter shown in Figs. 1-8, the

three upper collecting trays 10 arel providedalong their edges with `several rows of holes 22. The stock falls in this plansifter through the feed aperture 17 upon the uppermost collecting traylO, over which it is distributed in consequence of the oscillating movement imparted to the sifter. The

product carried by said tray falls then through the holes 22 upon the uppermost Woven screen .14. The slides 21 provided in connection with said collecting tray and said woven sieve kare closed. The discharge of this sieve, z' e. the part of the stock which is passing over the' woven screen passes through slot 15 Y'into one of the spaces 71, the spaces 71 of the several sieves placed one above the other forming vertical passage-Ways lying within the partition 5. The discharge passes then through said vertical passage-ways into one of the channels 18 and is .finally discharged through the opening 19 communicating with said lchannel 18.

The product passing through the uppermost woven screen '14 falls upon the collecting tray'l'() of the second sieve and then 'upon the'woven screen 14 of this sieve. The` through the slots 22 of this collecting tray slides 21 `'providedinconnection with this 20 are discharge second sieve are also closed since this sieve is arranged in the same manner in the sifter as the sieve first mentioned, the discharge of this sieve passes through the slot 15 into the same vertical passage 7l as the discharge of the firs-t sieve, it being consequently mixed with the discharge of the latter before leaving the plansifter.V The product passing through the woven screen of the second sieve falls thro-ugh the holes 22 of the collecting tray 10 of the third sieve upon the screen of the latter. around its center for 180 degreesy with regard to the first and second sieve, so that its yslot 15 communicates with the vertical pas-.

sage-way 71 lying ldiametrically vopposite the passage-way 71 with which communi-y cate the slots 15 of thel firsty and second sieves. The discharge of the third sieve travels into said assafre-wa 71 referred to. C

The product passing through the woven screen of the third sieve falls upon the collecting tra-y l0 of the fourth sieve.

moved (see Fig. 3 which is a section' onk the This third sieve is turned One of the upper slides 21 of this sieve is re` p line III-III through the lower left hand corner of Fig. 2), so that the product falling upon its collecting tray 10 is caused to,

travelinto the space confined by one yof the partitions 8 and forming with the same v spaces of the neighboring sieves arranged above and beneath .it a vertical passage-way,

z'. e. it is discharged into the space situated in Fig. 2 in the lower left hand corner. The product falling into said passage-way leaves then the pl-ansifter through the discharge branch 20 communicating therewith.

The discharge ofthe third sieve falls upon a bottom 23v arranged on the same level as the woven screen 14 of the fourth sieve and forming a partition of the vertical pasf sage-way 71 into which falls the' discharge of the third sieve. Said bottom 23 guides the stock falling upon it toward the woven screen of the fourth sieve. ,Thel product passing through the woven screen of the fourth sieve is caught up by the collecting trayof the fifth sieve and is then guided inv consequence of the removal of the slide 21 corresponding to the removed slide 21 of the fourth sieve, into the same vertical passageway as the product passing through the woven screen of the fourth sieve, so that said product is mixed with the product passing through the third screen before it leaves the plansifter. The product sifted by the woven screen of the fourth sieve passes into a vertical pas# sage-way situated in another corner of the plansifter lbetween the partitions 3 and 8 of the sieves arranged one above another, said passage-way being shown in the upper left hand corner of Fig. 8. The discharged product referred to is caught up in this passage-way on the level of the woven screen of Vthe fifth sieve by abottom (Fi-g. ar.

ranged at right angles to the longitudinal axis of said passage-Way. The bottom 24 causes the product falling upon it to travel ,into the sifting channel of the fifth sieve.

The product passing through the latter and falling-upon the collecting tray of the sixth sieve is guided into the same vertical passage-way as the products discharged by the woven screens of the third and fourth sieve respectively. The fifth sieve is arranged in the same manner within the plansifter as the third and fourth sieves, so that the product discharged by the woven screen of this fifth sieve falls into the vertical passage-way into which falls also the product discharged by the third sieve. The discharges falling down said passage-way are caused to travel through that of the passages 18 which communicates with it, and leave finally the plansifter through the discharge opening 19 communicating with said passage 18.

By rotating the single sieves through an angle of 90, 180 or 270 degrees and by providing for a communication between the collecting trays and the woven screens on the vone side and the appropriate vertical passage-ways provided in the corners of the plansifter (by moving some slides 21) on the other side and by inserting obstructions into the vertical passage-ways (for instance the bottoms 23 and 24), the bolted product ma be caused to travel in the interior of the plansifter along different paths, so that the quality of the discharged products may be changed at will. Thus, for instance, instead of mixing the sifted products of several sieves before they leave the plansift'er, each of said separated products of the sieves may be discharged singly out of the plansifter. IVhen desired, also the product passing through each single woven screen may be discharged separately. IVhen the stock is caused to pass along a zigzag line through the plansi-fter, e'. e., when it travels from the periphery of the sifter toward its center and then from the latter again toward the periphery of the sifter (as it is the case, for instance, with regard to the stock discharged by the third sieve), or vice versa, the pallets 16 have to be arranged on different sides of the sifting channel. When. the stock is caused to travel from the periphery of the plansifter toward its center (as shown, for instance, in Figs. 2 and 7), the pallets 16 have to be mounted on the inner side of the partitions 3, 8 and 9, while they have to be mounted on the outer side of the partition 9 when the stock is caused to travel through the plansifter from the center toward its periphery.

By inserting lat appropriate places obstructions into vertical passage-ways or by removing such obstructions, the discharges of all woven screens of the sieves may be caused to travel along uninterrupted zigzag lines, While the products passing through` the single woven sieves may be assembled at an appropriate place, or they may be discharged according to their different degrees of fineness at different places of tho plansifter.

The embodiment of the invention hereinbefore described comprises only one series of sieves. In such a plansifter only the stock supplied from one reducing machine can be graded and bolted. In contradistinction thereto, I have shown in Figs. 9-15 a plansifter adapted to be used for bolting stocks supplied from several reducing machines.

Referring to these Figs. 9-15, 3 denotes again the sides of the frame for the sieves and 4 are the reinforcing members. 8 denotes the partitions which are for confining the vertical passage-ways provided in the four corners of the plansifter and tted with superposed slide members 21. 1 is the bottom and 2 is the cover of the plansifter, said parts 1 and 2 being connected by means of screw-threaded bolts 241 (Figs. 11, 10), so that the frames of the sieves lie snugly against each other. In the center of the sieves are provided, in the same manner as in the plansifter first described, a plurality of vertical passage-ways 71. One of the latter communicates always through the slot l5 With the space provided above the woven screen 14 of the single sieves.

Within the vertical passage-ways 71 is situated a further passage-way 25, the vertical axis of which coincides with the vertical middle axis of the plansifter. 26 denotes a shaft pushed through the vertical passageway 25. The upper and lower ends of the shaft 26 extend through short hollow shafts upon which the balance weights 31 are fixed. Said short hollow shafts rest on their turn in bearings 27 fixed to the bottom 1 and cover 2 respectively. The driving pulley 30 is fixed upon a centr-ical shaft 28 running in a fixed bearing 29, the shaft 26 being fixed eccentrically in the driving pulley 30. When desired, the lower balance weight 31 can be mounted directly on the shaft 26, in which case the lower hollow shaft may be dispensed with. Ihe plansifter hangs on rods 311 which are secured to the ceiling of the building or to a special supporting frame. At the upper end of each vertical passage-way provided in the corners of the plansifter is provided an inlet opening 32 and at the lower end of each of them a discharge opening 33. The partitions 3e which are parallel to the outer sides 3 and each of which connects two partitions 8, confine together with said sides 3 and transverse partitions 35 eight vertical passage-ways 36. The latter are provided toward the collecting trays 10 and the woven screens 14 with slide members 37.

Thestock supplied to the inlet opening 32 situated in Fig. 10 in the lower left hand corner of the plansifter falls within the passage-way provided in said corner of the sitter beneath the opening 32 upon a bottom 24 inserted into said passage-way on the level. of the woven screen 14 of the top or first sieve. The bottom 24 causes the stock` the second sieve passes in consequence of theI removal of the corresponding slide member 37 (see Fig. 9) into a vertical passage-way 36 situated with regard to Fig. 10 above the corner passage-way above referred to. The collecting tray of the third sieve guides the product passing through the woven screeny of the second sieve into the passage-way 36 lying diametrically opposite the passageway 36 through which is discharged the product passing through the first sieve, the product passing through the second sieve being discharged through said passage-way 36.

The stock supplied to the second series of sieves passes through the inlet aperture 32 situated in Fig. 10 in the lower right hand corner and -falls upon a bottom 24 obstructing the vertical. passage-way. provided beneath said opening 32. This bottom guides the product to be ybolted toward the woven screen of the third sieve (Fig. 13). The discharge of the third sieve passes through the slot 15 into a vertical passage-way 71, which is angularly displaced relatively to the passage-way 71 through which falls the discharge of the first sieve unto the second sieve, to an' angle of 90 degrees. The discharge falls in this passage-way 71 upon a bottom 23 which guides it toward the woven screen of the fourth sieve. The discharge of this fourth sieve falls into that vertical passageway through the iipper portion of which is supplied the stock to be bolted in the second series of sieves. The product passing through the third sieve is fed by the collecting tray of the fourth sieve into the passage-way 36 situated in Fig. 10 on the left hand side of the inlet opening 32 for the stock to be bolted in thesecond series of sieves. The producty passing through the fourth sieve passes over the collecting tray of the fifth sieve into the passage-way 36 arranged diametrically opposite the passageway 36 through which 'is discharged the product passin through the third sieve.

the third series of sieves is The stock o series of sieves :ted to the inlet opening 32 situated with v' regard to 10 in the upper right hand` provided in a vertical passage-wayarranged beneath said` opening 32 unto the woven Y screen. ofthe'fift'h sieve (Fig. 14). The discharge oi this sieve passes through the slot 15 which is again angularly Ydisplaced with. i Y regard to the slot 15 of the third sieve to an` amount of degrees, into a third vertical passage-way 71' and is then guided toward the woven screen .of the siXth sieve by a Vbottom 23. The discharge of this sieve fallsl into that vertical passage-way through the upper portion of which is to be boltedy in the plansift r (Fig. 14). The product passing through the fifth sieve travels -over the collecting ltray of the sixth sieve into the vertical passage-way36 situated with regard to Fig. l0 in the lower left.

handcorner. The product passing through the sixth sieve travels' over the collecting supplied the sto le,

tray of the seventh sieve into the vertical` passage-way 36 lying diametrically opposite the last mentioned .vertical passage-way 36.

The stof-lr ing vertical passage-way. i

to be supplied l.to the. fourth.`

passes through the last inlet Also in this second embodiment, vany desired path may be impartd to the stock passing through the plansifter by turning the sieves angularly to an amount oli-90 or 180, 270 degrees withregard to one another andby using appropriate obstructing bottoms 23, 24and by removing certain of the slide members 21 and 27. When desired, also another number of sieves than that shown may be used, it being only -necessary to use for another number of sieves stacked one on the top of the other longer or shorter screw-threaded rods 241 `and another crank shaft.l i

From the description. of the two embodiments of the invention illustrated 1 in the drawings it will be understood, that in a plansifter according to this invention any desired sieve action may be obtained and that the'sieve action may be changed at will without the necessity ot changing anything in the single sieves. This 1s a very important feature contained in no other. plansifter. In the plansifters :hitherto proposed it was necessary to dispose in advance the inlet and dischargey openingsofthe'sieves in accordance with the sieve action'intended to be obtained. v An angular displacement ofy the sieves with regard to one another and an interchange of the sieves provided with suitable bolting means in the manner described with r gard to the novel plansifters can not be eii'ected in any of the plansifters hitherto known. Owing to the fact, that the crank shaft of the novel plansifter passes always through the center of the sieves, it is -possible to design plansifters comprising only one series of sieves (as it is the case. for instance, in the embodiment shown in Figs. 1-8), without that the advantage resulting from the arrangement of the| two series of sieves side by side is lost. This advantage attained in plansifters having two series of sieves arranged side by side with regard to the plansifters having only one series of sieves lies in the feature that the center of gravity of the balance weights used may be caused to fall into the plane passing through the center of gravity of the frames of the sieves. In plansifters having only one series of sieves said centers of gravity of the balance weights could never be brought into one and the same plane, so that it was impossible to obtain a regular working of the sifter.

In the novel plansifter according to this invention any kind of brushes may be used, this being even the case when it comprises only a single sifting channel (obtained owing to the provision of a partition 9), so

that, as shown in the drawings, the particularly advantageous rotating brushes about a central circular guide member may be used, whereby the guiding frames for the brushes have the same size for the whole set of sieves.

The shape of the sifting-channel may be varied by changing the arrangement of the partition 9, so that also the path of movement along which the stock is caused to travel through the plansifter may be varied. The sifting channel may be made, for instance, larger in the upper sieves to which more stock is usually supplied than to the lower ones (as shown for instance in Figs. 2. 7, 8 and 10), while a narrower sifting channel may be obtained in the lower sieves by increasing its length, as shown for instance in Figs. 16 and 17. According to Fig. 18, the sifting channel has such a shape that its width decreases gradually in accordance with the gradual decrease ot the stock passing along said channel toward the place of discharge. Also in this regard the miller may adapt the novel plansifter to any reouirernents by removing the partition 9 which is fixed to the transverse reinforcing member 6, and by replacing it by another one.

As shown in Fig. 20, the square sieves may be replaced by sieves having a circularshape. Fig. 19 shows a square sieve having eight vertical passage-ways 71 surrounding a central passage-way 25. This sieve has no outer vertical passage-ways for the discharge as it is only intended to be used for grading the stock by gradually dischargin parts of the latter, so that no outer vertica passageways for the discharge are required.

What I claim now as my invention is:

1. A plansifter of the class described, comprising a series of sieves, the sieves being stacked one on the top of the other and each being provided with a sifting channel for the stock to be bolted, inner vertical passageways arranged about the central portion of the sieves and extending through the whole series of sieves and each bordering on the sifting channel of the single sieves, outer Vertical passage-ways provided in the sieves and also bordering on the sifting channels of the sieves and situated outside said shifting channels and also extending through the whole series of sieves, the arrangement of the inner and outer vertical passage-ways relatively to one another and the shape of the sieves all designed in the same manner being such that upon a rotation of a single sieve about its center according to the division into vertical passage-ways, the same passage-ways as before are again obtained, and means for guiding the stock discharged by the sieves and the products passing through the screens of the latter into any one of said vertical passage-ways, so that the How-sheet of the plansifter can be changed at will.

2. A plansifter of the class described, comprisin g a series of relatively rotatable sieves, the sieves being stacked one on the top of the other and each being provided with a shifting channel for the stock to be bolted, inner vertical passage-ways arranged about the central portion of the sieves and extending through the whole series of sieves and each bordering on the sifting channel of the single sieves, outer vertical passage-ways also bordering on the sifting channel of the sieves and situated outside said sifting channels and also extending through the whole series of sieves, and means for repeatedly diverting the stock fallen into the vertically passage-ways, in order to cause the stock to travel on a zigzag line through the plansifter. I

3. A plansifter of the class described, comprising a series of sieves, the sievesbeing stacked one on top of the other and each being provided with a sifting channel for the stock to be bolted, vertical passage-ways arranged about the central portion of the sieves and extending through the whole series of sieves and each bordering on the sifting channel of the single sieves, outer vertical passage-ways also bordering on the sifting channel of the sieves and situated outside the sifting channels and also extending through the whole series of sieves, bottoms in thevertical passage-Ways, and sliding members provided between the sifting channels and the outer vvertical passage- 4. A plansifter of the class described,

comprising a series of relatively rotatable sieves, the sieves being stacked one on the top of the other, inner vertical passage-Ways arranged about the center of the sieves and, extending through the W'hole series of sieves,

outer lvertical passage-Ways also extending through the Whole series of sieves, rotating brushes for cleaning the sieves, the inner vertical passage-Ways forming guides for said brushes, a guiding ring for each brush lsurrounding one of said inner passage-Ways,

the diameter of the guiding rings being the same for the Whole set of sieves and a vclearance being left between each ring and its guide, and means for repeatedly diverting the stock fallen into the vertically passage- Ways, in order to cause the stock to travel on a zigzag line through the plansifter.

5. A plansifter of the class described, comprising a series of relatively rotatable sieves, the sieves being stacked one on the top of the other, inner vertical passage-Ways arranged about the center of the sieves and extending through the Whole series of sieves, outer vertical passage-Ways also extending through the Whole series of sieves, a partition Wall for each sieve` dividing the sifting j surface of the latter into sifting channels oi" different Widths and lengths, and means .for repeatedly diverting the stock into the vertical passage-Ways in order to cause the stock to travel on a zig-zag line through the plansifter.

6. A plansifter of the kind described, comprising a series of sieves, the sieves being stacked one on the top of the other, inner vertical passage-Ways arranged about the center ofthe sieves and extendingthrough the Whole series of sieves, and outer vertical passage-Ways in each sieve and also extending through the Whole series of sieves, said inner and outer passage-Ways being respectively similarly located vvith respect to the vertical axis to permit a partial relative rotation of the sieves with a consequent alinemhent of said passage-Ways.

7.y A plansiiter of the class described, having several inlets for the stock, comprising a series of sieves, the sieves being stacked one on the top of the other, inner vertical passage-Ways arranged about the center of `the sieves and extending through the Whole series of sieves, a sifting channell for the stock in the single sieves of the set of sieves, outer vertical passage-Ways arranged outside said sifting channels, the number of .said outer .passage-Ways forming a multiple in the corners of the sieves, an inlet for the` stock into the plansifter being` arranged above each of said outer passage-Ways, and slides in 'said outer vertical passage-Ways, said slides admittinga communication of the sifting channels with the outer vertical y i passage-Ways.

A plansifter comprising a series of superposed sieves, each having an inner 'vertical passage-Way anda plurality of outer spaced vertical passage-Ways, the inner pas'- sage-Ways of the screens being in alinement and Yforming a vertical chute and the outer passage-Ways'of the Vscreens being in alineinent and 'forming a plurality of chutes, said screens being relatively lrotatable about a vertical axis for shifting an outer p'assage- Way of one screen out of alinementvvith the outer passage-Way of an adjacent screen and into alinement with another outer passage- Way of said adjacent screen.

l0. In a plansifter, a sieve comprising anw Aouter frame and an inner vertical passageway, outer vertical passage-Ways arranged near said frame, a collecting tray located VWithin the frame and extending from the inner passage-Way to said frame andouter passage-Ways, said collecting tray being per'- forated near its `outer edge and dividing the sieve into an upper and lovverk chamber, means for placing one of said chambers in communication with the inner vertical passage-Ways, partitions separating said chambers from theouter vertical passage-Ways, and doors arranged 'in said partitions `to permit said chambers to communicate With said outer passage-Ways.

l1. A sifting apparatus comprising a series of superposedv relatively adjustable screens, each having an outer frame and an inner vertical passage-Way located Within the frame and spaced away therefrom, the vertical passage-Ways of the superposed screens forming a continuous vertical passage, and outer vertical passage-Ways also arranged Within the sieve frames and forming continuous passage-Ways, said inner and outer passage-Ways being respectively similarly located With respect to the vertical axis to permit a partial relative rotation of the screens With a consequent alineinent of said passage-Ways.-

ion

iio

12. A sifting apparatus comprising a series of superposed relatively adjustable screens, each having an outer frame and an inner passage-Way, a collecting tray arranged Within each frame and dividing the interior ofthe sieve into two chambers, outer passage-Ways also arranged Within each frame, means to permit material to pass from the chambers of the sieves into said passage-Ways, and Woven sheets placed be- 10 screens with aconsequent alinement of said 15 passage-Ways.

JACOB PETER.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents,

Washington, D. C.

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