US1973864A - Centrifugal sieving machine - Google Patents

Description

Sept. 18, 1934. BIFFAR v 1,973,864

GENTRIFUGAL SIEVING MACHINE I Filed ma 25, 1932 2 Sheets-Sheet 1 m srun IIIIIIIII IN I III! Sept. 18, '1934.

A. BIFFAR CENTRIFUGAL SIEVING MACHINE Filed May 25, 1932 2 Sheets-Sheet 2 UNITED STATES PATENT OFFICE CENTRIFUGAL SIEVING MACHINE Andreas Bilfar, Miltenberg-on-the-Main, Germany Application May 25, 1932, Serial No. 613,479 In Germany September 5, 1931 11 Claims. (Cl. 9234) I have filed an application in Germany, on the the efficiency of the machine is impaired and th September, 1931; in Sweden, on the 5th that an insufficient quantity of fibre passes November, 1931; and in Finland on the 19th through the sieve, a considerable part of the lat-, November, 1931. ter passing into the waste material.

5 The present invention relates to a, centrifugal In contradistinction to this, according to the 60 sieving machine, particularly for paper pulp, cel-- invention, the sievingspace bounded by the cylinlulose, wood pulp or other fibrous materials susdrical sieve and the drum is arranged so as to pended in liquid. Centrifugal sieving machines constitute a uniform sieving zone which is of of this kind are usually provided with a stationthe same cross section at all parts and to which ary cylindrical sieve into which the suspended the water is supplied from the drum uniformly 65 fibrous material and water for thinning purposes over its whole length. are introduced and in which a centrifugating Further characteristic features of the invenwheel or a drum provided with centrifugating tion will be elucidated in the following descripblades rotates. The centrifugating blades drive tion with reference to the accompanying drawthe fibrous material through the cylindrical sieve. ings which illustrate by way of example some 70 The invention relates more particularly to cenconstructional forms of a centrifugal sieving matrifugal sieving machines provided with a cenchine according to the invention. trifugating drum arranged within the cylindri- Referring to the drawings: cal sieve, wherein the fibrous material and the wa- Fig. 1 shows one constructional form of a center are introduced into the machine in the longitrifugal sieving machine. according to the inven- 75 tudinal or axial direction of the cylindrical sieve tion in vertical longitudinal section, in opposite directions, the fibrous material being Fig. 2 shows the centrifugating drum and the introduced into the space between the sieve and cylindrical sieve appertaining thereto in vertical the drum whilst the water is introduced into the, cross section,

drum itself- The walls of the drum a e pro- Figs. 3 and 4 show details of different con- V d with perforations passages t ugh structional forms of the centrifugating drum in which the water passes into the space between vertical cross section, the drum and the sieve and thins down the ma- 'Fig. 5 is a section taken on line V-V of Fig. 1, terial. In the known Centrifugal sieving 1113- Fig. 6 is an elevation of a centrifugating wheel chines of this kind the drum is constructed of for the introduction of the material (direction 5 conical form and increases in breadth from the X) indicated in Fig. 1, side of the machine at which the fibrous mate- Fig. 7 is an elevation of the centrifugating rial is introduced into the Siev t w the DDO- wheel for the introduction of the water (direcsite side at which the water is introduced into tion Y) indicated in Fig, 1,

the drum. The material to be sieved passes in Fig, 8 shows to a, larger scale a, detail of Fig, 1,

the longitudinal direction of the sieve into the and v space between the drum and the sieve and moves Fig. 9 shows another constructional form of a towards the side of the sieve at which the water sieving machine according to the invention, is introduced into the drum. Inasmuch as the The reference numeral 1 denotesa, housing in 4.0 drum increases in breadth in the same direction which a stationary cylindrical sieve 2 is arranged. the spac between the sieve and the drum on Through the cylindrical sieve a shaft ljournalled the side at which the water is introduced is subin the housing at 3 provided with driving stantially narrower than on the side at which pulley 5 passes co axiauy on the h ft 4 a the material enters the sieve. As a consequence trifugating drum 6 is mounted which is provided 45 of this t material 9 9 denser at i Part with external blades '1 and internal blades s. of the slew T thmnmg water.enter.s directly In the wall of the drum 6 perforations or passages only into this part of the sieve masmuch as the drum is only provided at its broader 9 q' t be ed is introduced into part with perforations which allow the water to th i 9 slev h v 1 t 10 f trate from the drum into the space between Slevmg i q 6 mm 50 Dene WhlCh it passes in axial direction into the space the drum and the 516% between the sieve 2 and the centrifugating drum As a result of this the fibrous material is not uniformly treated along the length of the i 6. The water is introduced through an 1nlet 11 ing zone comprising the space between the drum provided at the other end of the sieving machine, 55 and the sieve. The consequence of this is that and passes in the opposite direction to the mateno rial but likewise in axial direction into the drum itself and from this latter through the passages 9 into the cylindrical sieve. The sieved material is collected below the sieve and withdrawn whilst the residual material which contains the splinters and knots and does not pass through the sieve is led off through an outlet 10a.

The centrifugating blades are arranged on the centrifugating drum in pairs each consisting of one external blade '7 and one inner blade 8. As shown in Fig. 2 the inner blade 8 is displaced slightly backwards in the direction of rotation of the drum with regard to. the external blade 7. The passage 9 in the drum is arranged in such manner that it is located in front of the internal blade but behind the external blade, which latter is fixed to the drum by means of a flange provided with a corresponding passage. In the constructional form according to Fig. 2 the passage in the drum and in the flange runs in a backwardly inclined direction from the interior to the exterior.

In the constructional form shown in Fig. 3 the internal blade and the external blade are arranged in the same plane and the passage is located in front of them both. In the constructional form shown in Fig. 4 the outer blade which extends beyond the inner blade is provided with a radial bore 12 through which thewater flows outwards from the drum.

The passages in the wall of the drum are adapted, as shown in Fig. 1, to be covered, partly covered or entirely uncovered by means of slide members 13 provided with openings 14 which can be brought into entire. or partial register with the openings 9 according to the adjustment. of

the slide members 13. To the slide members levers 15 are pivotally connected which are journalled in brackets 16 provided on the hub 17 of the drum and are, forked at their free ends, the forked parts engaging pins 18 provided on the periphery of an internally threaded member 19. The said internally threaded member co-operates with a screw spindle 20 which is mounted in the interior of the hollow drum shaft so as to be rotatable co-axially with the latter. In the hollow drum shaft 4 slits are provided for the passage. of the levers 15. The spindle can be operatedby means of a hand wheel 21 mounted on itse'xternal projecting end.

The above described constructional form of the device for the adjustment of the slides is employed at the same time in the present case for the adjustment of the external blades which are arranged so as to be radially adjustable according to the invention. In the constructional form of the sieving machine illustrated in the drawings the external blades are divided longitudinally into two parts. At their front part the blades are rigidly attached to the periphery of the drum. The rear part of the blade is pivotally connected at the end nearest to the material inlet at 22 to the front part of the blade so as to be capable of swinging, whilst the other end of the rear part of the blade is connected to a linkage 23, 23'. The said linkage is pivotally connected at its other end with the aforesaid internally threaded member or with a second threaded member provided on the spindle 20, so that on displacement of the slide member the outer blade is simultaneously displaced.

For the purpose of regulating the supply of the material and water respectively a float 24 (Fig. 1) is provided which floats in the unsieved waste material collected below the sieving machine or at another suitable place in a container 25. The container is connected to an over-flow vessel 26, the over-flow into the saidvessel being adjusted by means of a slide 2'7.

To the float 24 a linkage 28, 29, 30, 31 is connected which is pivotally connected at its other end to slides 32 and 33 provided in the material inlet 10 and the water inlet 11 respectively. When the quantity of material in the container 25 increases the float rises and thereby causes the slide 33 in the water inlet 11' to move so as to increase the size of the inlet passage whilst at the same time causing the slide 32 in the material inlet 10 to move so. as to throttle the material inlet. When the amountof material in the container 25 decreases the float sinks and the reverse action takes place.

The material and the water are forced through the machine by means of centrifugating wheels 34 and 35 which are arranged in front of the sieve and in front of the drum respectively. Whilst the blades of the drum extend entirely in an axial direction, the blades of the wheels 34, 35 are inclined to the axial direction so as to obtain a better feeding action.

In the constructional form shown in Fig. 9 the fibrous material is passed through a pipe system arranged behind a sand collector 36. The said pipe system comprises a horizontal shaft 3'? on which a long pipe 38 is mounted in such manner that a free space remains between the shaft and the pipe. On the periphery of the said pipe blades 39 are mounted. The shaft 37 together with the pipe 38 passes through a stationary tubular sieve 40. The pipe 38 provided with blades is connected to the inlet 11 for the water in such manner thatthe latter can pass into the said pipe 38 and thence through the passages into the space between the pipe 38 and the sieve 40. The fibrous material passes from the inlet 10 into the interior of the tubular sieve 40. With this arrangement the fibrous material is effectively washed and sorted or sifted. The fibrous material passes out of the pipe system through the sieve and is discharged underneath.

The sorting or sifting action can be still further improved by providing pumps in the pipe system, one of which is adapted to force the.

material into the space inside the sieve, whilst the other forces the water into the rotating centrifugating pipe.

With this constructional form of. the invention the sorting or shifting is substantially simplified inasmuchas the pipe system can be made of any desired length and it is consequently unnecessary to erect a number of sieving machines together with the material and water supply and discharge conduits appertaining thereto so that the costs of the installation are substantially lower.

I claim:

1. A horizontal centrifugal sieving machine, wherein the material to be sieved is introduced axially in counter current to a stream of water, comprising in combination: a cylindrical sieve; a cylindrical drum arranged in said sieve co-axially therewith and extending over the whole length of said sieve; blades on said drum running longitudinally thereof; a sieving zone bounded by said sieve and said drum-and having the same cross section at all parts; means for rotating said drum; means for supplying maof said drum, the water passing through said passages into said zone and being distributed uniformly over the whole length thereof; and slide members arranged on the periphery of said drum and adapted to control the size of said passages.

2. A horizontal centrifugal sieving machine, wherein the material to be sieved is introduced axiallyin counter current to a stream of water, comprising in combination: a cylindrical sieve; a cylindrical drum arranged in said sieve coaxially therewith and extending over the whole length thereof; a hollow shaft for rotating said drum; longitudinal blades on said drum; a sieving zone bounded by said sieve and said drum and having the same cross section at all parts; means for supplying material to be sieved to said zone; means for supplying water to the interior of said drum; passages distributed uniformly over the periphery of said drum, the water passing through said passages into said zone and being distributed uniformly over the periphery of said drum; a threaded spindle arranged in said hollow shaft and rotating co-axially therewith, said spindle being adjustable from the exterior; an internally threaded member co-opcrating with said spindle; and slide members arranged on the periphery of said drum and coupled with said internally threaded member, said slide members being adapted tocontrol the size of said passages.

3. A horizontal centrifugal sieving machine, wherein the material to be sieved is introduced axially in counter current to a stream of water, comprising in combination: a cylindrical sieve; a cylindrical drum arranged in said sieve co-axially therewith and extending'over the whole length of said sieve; internal blades on said drum running longitudinally thereof; radially adjustable external blades on said drum running longitudinally thereof; a sieving zone bounded by said sieve and said drum and having the same cross section at all parts; means for rotating said drum; means for supplying material to be sieved to said sieving zone; means for supplying water to the interior of said drum; passages distributed uniformly over the periphery of said drum, the water passing through said passages into said zone and being distributed uniformly over the whole length thereof; and slide members arranged on the periphery of said drum and adapted to control the size of said passages.

4. A horizontal centrifugal sieving machine, wherein the material to be sieved is introduced axially in counter current to a stream of water, comprising in combination: a cylindrical sieve; a cylindrical drum arranged in said sieve coaxially therewith and extending over .the whole length of said sieve; a sieving zone bounded by said sieve and said drum and having the same cross section at all parts; means for rotating said drum; means for supplying material to be sieved to said sieving zone; means for supplying water to the interior of said drum; passages distributed uniformly over the periphery of said drum, the water passing through said passages into said zone and being distributed uniformly over the whole length thereof; slide members arranged on the periphery of said drum and adapted .to cone trol the size of'said passages; internal blades on said drum running longitudinally thereof; external blades on said drum running longitudinally thereof and pivoted at the end adjacent to said means for supplying material; and a device arranged at the other end of said external blades for displacing them radially,

5. A horizontal centrifugal sieving machine, wherein the material to be sieved is introduced axially in counter current to a stream of water, comprising in combination: a cylindrical sieve; a cylindrical drum arranged in said sieve coaxially therewith and extending over the whole length thereof; a hollow shaft for rotating said drum; longitudinal internal and external blades on said drum; a sieving zone bounded by said sieve and said drum and having the same cross section to all parts; means for supplying material to be sieved to said zone; means for supplying water to the interior of said drum; passages dis tributed uniformly over the periphery of said drum, the water passing through said passages into said zone and being distributed uniformlyover the periphery of said drum; a threaded spindle arranged in said hollow shaft and rotating coaxially therewith, said spindle being adjustable from the exterior; an internally threaded member co-operating with said spindle; slide members arranged on the periphery of said drum and coupled with said internally threaded member, said slide members being adapted to control the size of said passages; and means for radially adjusting said external blades, comprising a linkage coupling said external blades with said internally threaded member.

6. A horizontal centrifugal sieving machine, wherein the material to be sieved-is introduced axially in counter current to a stream of water, comprising in combination: a cylindrical sieve; a cylindrical drum arranged in said sieve co-axially therewith and extending over the whole length thereof; a hollow shaft for rotating said drum; internal and external longitudinal blades arranged in pairs on said drum; a sieving zone bounded by said sieve and said drum and having 1 5 the same cross section at all parts; means for supplying material to be sieved to said zone; means for supplying water to the interior of said drum; passages distributed uniformly over the periphery of said drum, the water passing through 2 said passages into said zone and being distributed uniformly over the periphery of said drum; a threaded spindle arranged in said hollow shaft and rotating co-axially therewith, said spindle being adjustable from the exterior; an internally threaded member co-operating with said spindle; and slide members arranged on the periphery of said drum and coupled with said internally threaded member, said slide members being adapted to control the size of said passages.

7. A horizontal centrifugal sieving machine, wherein the material to be sieved is introduced axially in counter current-to a stream of water, comprising in combination: a cylindrical sieve; a cylindrical drum arranged in said sieve co-axially therewith and extending over the whole length thereof; a hollow shaft for rotating said drum; a sieving zone bounded by said sieve and said drum and having the same cross section at all parts; means for supplying material to be sieved to said zone; means for supplying water to the interior of said drum; passages distributed uniformly over the periphery of said drum, the water passing through said passages into said zone and being distributed uniformly over the periphery of said drum; a threaded spindle arranged in said hollow shaft and rotating co-axially therewith, said spindle being adjustable from the exterior; an internally threaded member co-opcrating with said spindle; slide members arranged 5 on the periphery of said drum and coupled with said internally threaded member, said slide members being adapted to control the size of said passages; and internaland external blades arranged in pairs on said drum, the internal blade of each pair being staggered with regard to-the corresponding external blade in such manner that said passages open at their inner ends in front of the internal blades and at their outer ends behind the external blades.

8. A horizontal centrifugal sieving machine, wherein the material to be sieved is introduced axially in counter current to a stream of water, comprising in combination: a cylindrical sieve; a cylindrical drum arranged in said sieve co-axially therewith and extending over the whole length thereof; a hollow shaft for rotating said drum; a sieving zone bounded by said sieve and said drum and having the same cross section at all parts; means for supplying material to be sieved to said zone; means for supplying water to the interior of said drum; passages distributed uniformly over the periphery of said drum, the water passing through said passages into said zone and being distributed uniformly over the periphery of said drum; a threaded spindle arranged in said hollow shaft and rotating coaxially therewith, said spindle being adjustable from the exterior; an internally threaded member co-operating with said spindle; slide members arranged on the pe-' riphery of said drum and coupled with said internally threaded member, said slide members being adapted to control the size of said passages; and internal and external blades arranged in pairs on said drum, the internal blade of each pair being staggered with regard to the corresponding external blade in such manner that said passages open at their inner ends in front of the internal blades and at their outer ends into bores provided in the said external blades.

9. A horizontal centrifugal sieving machine, wherein the material to be sieved is introduced axially in counter current to a stream of water, comprising in combination: a cylindrical sieve; a cylindrical drum arranged in said sieve coaxially therewith and extending over the whole length thereof; a hollow shaft 'for rotating said drum; longitudinal radial blades on said drum; a sieving zone bounded by said sieve and said drum and having the same cross section at all parts; centrifugating blades for feeding material to be sieved to said zone, said blades being arranged in front of said drum and inclined to the axis of said hollow shaft; centrifugating blades for feeding water to the interior of said drum, said blades being arranged behind said drum and inclined to the axis of said hollow shaft; passages distributed uniformly over the periphery of said drum, the water passing through said passages into said zone and being distributed uniformly over the periphery of said drum; a threaded spindle arranged in said hollow shaft and rotating co-axially therewith, said spindle being adjustable from the exterior; an internally threaded member co-operating with said spindle; and slide members arranged on the periphery of said drum and coupled with said internally threaded member, said slide members being adapted to control the size of said passages.

10. A horizontal centrifugal sieving machine, wherein the material to be sieved is introduced axially in counter current to a stream of water, comprising in combination: a cylindrical sieve; a drum arranged in said sieve co-axially therewith; a uniform sieving zone bounded by said sieve and said drum and having the same cross section at all parts; means for rotating said drum; means for supplying material to be sieved to said sieving zone; means for supplying water to the interior of said drum, the water passing through said drum to said zone being distributed uniformly over the whole length of said zone; a container for the reception of the overflow 0f non-sieved material arranged below the apparatus; a float in said container; and throttling devices controlled by said float and associated with said means for supplying material to be sieved and said means for supplying water.

11. A horizontal centrifugal sieving machine, wherein the material to be sieved is introduced axially in counter current to a stream of water, comprising in combination: a cylindrical sieve; a cylindrical drum arranged in said sieve co-axially therewith and extending over the whole length thereof; a hollow shaft for rotating said drum; longitudinal blades on said drum; a sieving zone bounded by said sieve and said drum and 110 having the same cross section at all parts; means for supplying material to be sieved to said zone; means for supplying water to the interior of said drum; passages distributed uniformly over the periphery of said drum, the Water passing through said passages into said zone and being distributed uniformly over the periphery of said drum; a threaded spindle arranged in said hollow shaft and rotating co-axially therewith, said spindle being adjustable from the exterior; an internally threaded member co-operating with said spindle; slide members arranged on the periphery of said drum and coupled with said internally threaded member, said slide members being adapted to control the size of said passages; a container for the reception of the overflow of non-sieved material arranged below the apparatus; a float in said container; and throttling means associated with said means for supplying material to be sieved and said means for supplying water, said throttling means being controlled by said float in such manner that, when the level in said container rises, the supply of material is throttled and the water supply is increased, and, when the level in said container sinks, the supply of' material is increased and the water supply is throttled.

ANDREAS BIFFAR.

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