US2329799A

US2329799A - Device for the distribution of stock on the wire parts of papermaking machines

Info

Publication number: US2329799A
Application number: US312989A
Authority: US
Inventors: Thorsen Kristen Andreas
Original assignee: Individual
Current assignee: Individual
Priority date: 1939-01-09
Filing date: 1940-01-08
Publication date: 1943-09-21
Anticipated expiration: 1960-09-21

Description

llululllyll ll lull laminar K14. flame/Z Alfomeg 5 Sheets-Sheet l (LOW Sept. 21, 1943. K. A. THORSEN DEVICE FOR THE DISTRIBUTION OF STOCK ON THE WIRE PART OF PAPERMAKING; MACHINES Filed Jan. 8, 1940 Sept. 21, 1943. K, THORSEN 2,329,799

, DEVICE FOR THE DISTRIBUTION OF STOCK ON THE WIRE PART OF PAPERMAKING MACHINES Filed Jan. 8, 1940 5 Sheets-Sheet 2 Inbpntor m. Mame/7 y Y A Home):

Sept. 21, 1943. K. A. THORSEN DEVICE FOR THE DISTRIBUTION OF STOCK ON THE WIRE PART OF PAPERMAKING MACHINES Filed Jan, 8, 1940 5 Sheets-Sheet 3 Inventor /M 7/70/56 X A Home Sept. 21, 1943. K. A. THORSEN 2,329,799

. DEVICE FOR THE DISTRIBUTION OF STOCK ON THE WIRE PART OF PAPERMAKING MACHINES Filed Jan. 8,1940 5 Sheets-Sheet 4 lnventoi Sept. 21, W43. K. A. THORSEN 2,329,799

DEVICE FOR THE DISTRIBUTION OF STOCK ON THE WIRE PART OF PAPERMAKING MACHINES Filed Jan. 8, 1940 5 Sheets-Sheet 5 A Home Patent ed Sept. 21, 19 43 2,329,799 DEVICE FOR THE DISTRIBUTION OF STOCK ON THE WIRE PAR MACHINES Kristen Andreas Thorsen,

TS OF PAPERMAKING Grenoble, Isere,

France; vested in the Alien Property Custodian Application January 8, 1940, Serial No. 312,989 In Great Britain January 9, 1939 12 Claims. (01. 92-44) The present invention relates to an improved method of and means for the manufacture of p p v In paper making machines it has been usual to project a layer of stockor paper pulp upon one end of an endless moving band of wire gauze through an opening, sometimes termed a slice,

which is adjustable in depth and which is disposed immediately above the travelling endless wire gauze belt;the speed of delivery of the pulp or stock has usually been adjusted to be substantially that or the linear speed of the travelling wire gauze conveyor.

The paper made in this manner has a much lower transverse resistance. than its longitudinal resistance. This is due to the fact that under the eilect of passing through the distributing slice, the majority of the fibres in the stock are set in the longitudinal direction.

A paper of this kind is suitable for newsprint since it has to withstand comparatively high longitudinal pulls in the rotative printing machine.

For all other applications however, this will be a drawback since such paper has not the nice aspect of a paper, the fibres of which are arranged along all possible directions, it will iurther not remain fiat alter slight absorption of moisture, and lastly, for an application necessitating a paper of given. resistance, it will be necessary to choose a sheet having the desired resistance in thetransverse direction, therefore of a greater thickness than would be necessary if the. resistance were the same in all directions.

In theabsence of precautionary measures, difliculties moreover would be present in the distribution otthe stock to obtain a layer of pulp of uniform thickness'from one side of the forming wire conveyor to the other, and if the stock is being delivered at high speed there is a tendency for the stream to carry air bubbles with it, retarding the drainage of the paper stock on the forming wire and resulting in a badly felted and cloudy sheet.

An endeavor has been made to remedy these drawbacks and to criss-cross the fibres by sub- Jecting the wire to a rapid shaking motion in the transverse direction, the amplitude of the shake being 4 to 12 mm. and the number of snakes 150 to 400 per minute, but this results in a serious complication of the machine, while the desired effect is far from being attained since the transverse resistance of the paper will, even in this case, amount to only 50-60% of the longitudinal resistance. I

An object of the present invention is to render a machine capable of manufacture or a greater variety of paper, whilst another object is to provide means whereby the distribution of fibre in the stock or pulp stream reaching the forming wire, conveyor can be under control; a further object is to provide means whereby air bubbles carried along with the pulp stream can bereleased.

According to the present invention paper pulp or stock under a dynamic or static head, that is to say fed by a-pump or alternatively by gravity from a tank, passes from a slice or outlet onto a travelling woven forming wire or conveyor. The direction of flow of the paper stock is altered between the point where it leaves the said slice and the place where it reaches the forming wire conveyor.

It will be preierred that the direction of flow be altered smoothly and constantly.

In certain cases it may be desirable to deviate the direction of flow of the paper stock on leaving the slice in one direction, and then to turn it smoothly into the opposite direction prior to its arrival upon the forming wire or the like conveyor.

The invention is more particularly described with reference to the accompanying drawings in which:

Figure 1 is a sectional elevation 01 one end of a paper making machine showing the outlet mouth or slice of the present invention.

Figure 2 shows an alternative form of outlet mouth or slice.

Figure 3. is a side elevation of a further form of construction, in which the position of the outlet mouth is adjustable.

Figure 4 is a corresponding plan view.

Figure 5 is a side sectional detail view showin another form of construction.

Figures 6 and '7 show in side elevation further alternative forms of construction.

In the arrangement shown in Figures 1 and 2,

the pulp coming from the screens is either fed vto the collecting pipe i' by a pump ofconstant delivery and pressure (which-is not shown), or is fed toa reservoir 2 in which the head is adjustable, to give a static head of pulp, so as in each case to obtain an outlet speed of the pulp which approximates to the speed of travel of the wire band conveyor i4.

The pulp will therefore be fed by a dynamic or static head to a distributor 3 either through flexible'pip'e connections 4, or through a rectangular opening at the bottom of the reservoir 2. The

2 asaavea pipes 4 may be replaced by a single rectangular conduit.

A perforated cylinder 5 of known type is placed close to the outlet opening of the distributor in order to even out the distribution and to prevent the possible accumulation of fibres in bundles.

The outlet spout or slice of the distributor 3 is formed by the fixed wall I and an adjustable lip 8. The adjustment of the lip 8 is controlled by a hand-wheel 8, operating worm gears III, which adjust the angular position of the supporting arms ll of the transverse shaft l2, thesearms being positively connected to the lip 8 by a number of hand screws I 3 by which the depth of opening at different points across the outlet can be adjusted to maintain an even flow across this width.

With the above mechanism, it is therefore possible to adjust the depth of the outlet spout the full width of the wire, which might be necessary due to an uneven arrival of the pulp stream at the forming wire, and in order to obtain a regular depth of the pulp on the full width of the wire 4.

At the outlet spout 8, the pulp enters the downward directed and curved fiow plate III. In order to reduce friction between the fibres and the fiow plate ii, a film of water is introduced through the narrow opening I8, between this flow plate and the layer of pulp, being so arranged as to provide a water film over the whole length of the distributor 3.

As the pulp approaches the outlet spout 8, its speed increases considerably and due to this the fibres will progresively be aligned in the direction of the pulp stream. The speed is still further increased by the gravity fall over the flow plate, so that the fibres, when the pulp reaches the wire it, are'mostly all arranged in the direction of travel of the wire. As a consequence of the speed and the rapid curve of the fiow plate II, the pulp will be subjected to centrifugal force.

I As the pulp is very turbulent when leaving the outlet spout B it lies a tendency to take up air, which is undesirable for the formation of the sheet, but by reason of the centrifugal action imposed on the pulp in passing over the fiow plate It, the air bubbles will burst and leave the pulp.

When arriving on the wire, the majority of the fibres will take up a longitudinal direction as a consequence ofthe increase in speed of the pulp in passing through the distributor 3 and in running down the fiow plate I! and the paper obtained will therefore show a much higher strength in the running direction than in the transverse direction of the wire ll; the paper obtained will be consequently particularly suitable for newsprint, as this paper has to withstand comparatively high longitudinal draws in passing through the rotary printing machines.

In order to increase the gravity fall effect, the slope I! may be extended as shown on Figure 2,

where the pulp leaving the distributor I1 is ob.-"v

liged to follow the flow plate i8, and then follow tributor where it isbaflled by the partition 2|, which causes the pulp to spread out transversely. The usual perforated cylinder 5 is provided to evenout the distribution and to prevent bunching of the fibres.

The outlet spout 8 of the distributor 20 is formed by the fixed wall 22 and the adjustable lip 8. The adjustment of the lip 8 is controlled by a hand wheel 23, moving worm gears 24, which adjust the angular position of the transverse shaft 25. On this shaft is fixed a series of eccentrics 26 which, by the rotation of the shaft 2!, will move forwards or backwards the connecting rods 21, which, with the help of the levers 28.

' pulpby the turbulent outflow from the outlet a second fiow plate is before arriving on the spout B. y

A film of water-is introduced between the layer of pulp and the flow plates-through the narrow opening l8, thus avoiding friction between the fibres and the flow plates. I

Leaving the downward directed and curved flow plate 30, the pulp comes upon another fiow plate ll, which is directed upwardly towards the wire I. On this latter flow plate, the pulp stream will be slowed down, which effect results in a thorough mixing of the pulp and causes the fibres to be arranged in all directions.

The distributor 20 is provided with journals 82, r t in the supports 33. A hand wheel 34 controlling worm gears 3! enables the distributor to rotate around the axis of the journals 82 to a desired position, so that the direction of the jet of pulp with regard to the plate Il may be regulated exactly.

The distributor 28 may also be brought nearer to or farther away from the flow plate Si by means of the adjusting nuts 38.

The lever arms 31 fixed on the shaft 38. which may be rotated by worm gears It by means of the handwheel 4| and the intermediate gears 4|, will enable the distributor 28 to be placed in any position between the extreme positions A and B.

when the distributor 28 is placed in the position A, a paper with a maximum strength in the direction of travel of the wire will be obtained, and when it is placed in the position B, the paper obtained will have its maximum strength in a direction transverse to the direction of travel of 19 wire.

The flow plate 3| ls fixed to two or several frames 42.

In order to simplify its construction, the form of the flow plate is shown cylindrical, but it may have other shapes, in which case the distributor "is displaceable in guides of the same contour as the flow plate.

By a suitable adjustment of the distributor II, it is even possible for the pulp jet to arrive on the wire without passing over any part of the flow plate 8|. v

For slow speed machines the flow plate 38 may be eliminated and the distributor may be constructed as at .48, Figure 5. In this distributor.

the partition It will compel the pulp to spread With present types of paper making machine when it is desired to adjust the width of the sheet, it is either necessary to stop the machine, resulting in a' loss of output, or to trim-oil a strip on either side of the sheet'at the couch roll being firmly connected to the lip 8 by a number of individually adjustable hand screws, by which the depth of opening of the outlet spout 6 at in order to obtain the desired width of finished.

paper web. At the couch roll, however, the pulp is dewatered and consequently the trimmed-oil! strip requires treatment by independent equipment to render it a density suitable for it to again mix with the pulp stream.

The arrangement 01' Figures 3 and 4 show a means by which the sheet width can be adjusted whilst the wire is running and the eliminated pulp strips, whilststill in a liquid state, can be returned directly to the pulp coming along through the flexible pipe connections 4. To arrive at this result, two side frames 43 are provided to limit the width of the sheet, one on each side of the wire. These side frames may be adjusted in the transverse direction by any desired means. The maximum width of the sheet is indicated by C and the minimum width by D.

The edge 44 of the side frames 43 will divide the layer of pulp into three parts, the central part of which follows the wire. The two side portions will contact with the plates 45, which compel the pulp to follow the channels. 46 to arrive finally into the gutter 41. From this, the pulp will travel through the pipe 48 to arriv in a reservoir, where it is mixed with the pulp fed to the distributor 20.

Figure 6 shows the same arrangement as Figures 3 and 4, with the diflerence that the flexible pipe connections 4 are replaced by fixed pipe con nections.

The pulp is fed by a constant delivery and pressure pump or from a reservoir with a constant head, through the pipe from which it is distributed to the pipes 52,- which terminate in the swivel joints 53. The pulp thenenter into two other pipes 54, through which it arrives at the distributor 20, passing through the two tapered mouthpieces 55. The lower extremities 56 of the pipes 54 are fixed to the extremities of the shaft 38, by couplings 51, the shaft 38 adjusting the position of the distributor along the flow plate 3|, being jointed to the pipes 54 which feed the pulp to the distributor, and connected to the pipes 52, in fixed position, by the swivel joints 53.

The pipes 54, being slightly flexible metal, will permit of a small degree of adjustment of the.

distributor 28, by means of the nuts 36 and the worm gears 35.

Figure 7 shows an arrangement of pulp distribution with downward and upward directed flow lates in a flxed position.

The pulp is fed to the distributor 58 through the flexible pipe connections 4 or through a single inlet extending over the whole width or the distributor. In passing into the distributor, the pulp will be baffled against the partition 59, which will force it to spread out transversely in the distributor 58. A perforated cylinder 5 evens out the distribution and prevents the bunching of the fibres.

The outlet spout-or slice 6 is formed by the fixed wall 60 and an adjustable lip 8.

The adjustment of the lip 8 i controlled by the handwheel 9 through worm gear it), which adjusts the angular position of the supporting arms H- of the transverse shaft l2, the e arms width of the spout can be adjusted.

Leaving the outlet spout 6 the pulp is downwardly directed on to the rapidly curved flow plate 5|.

In 'orderto avoid friction between the ,iibres and the flow plate, a fllm of water is introduced between this flow plate and the layer of pulp through the narrow opening l6, which extends over the whole width of the distributor 58.

'As a consequence of the increased speed of flow due to gravity and to the rapid curving of the flow plate 8|, the pulp will be subjected to strong centrifugal action and will even out, so that the thickness of the layer of pulp will be the same on the whole width of the flow plate permitting a sheet of regularthickness to be obtained on the wire, and air bubbles will burst and leave the pulp.

After having gone over the downward directed flow plate 6|, the pulp flows on to the upwardly directed flow plate 62. On this flow plate, the

any point from one edge to the other across the pulp stream will slow down, which results in a thorough mixing of the pulp, the fibres being arranged in all directions. As a result, a paper will be obtained of a transverse strength about equal to its strength in the direction of flow of the pulp stream.

The width of the sheet on the wire may be adjusted whilst the machine is running, with the help of the side frames 63, which may be moved in the transverse direction by the screwed rods 84. Each one; of the side frames 63 is provided on the outside and immediately against the outlet spout 6 with a gutter 66, provided with an outlet pipe 61, which communicates cipient 41, from which the pulp flows by the pipe 48, the gutters receiving the jet of pulp at their extremities in the entire region which is not contained between the plates 63 for dispersion, to determine the width of the paper sheets or foils.

I declare that what I claim is:

1. A paper making machine comprising in combination means to feed a stream of paper pulp under pressure, an outlet nozzle or slice predetermining the cross-sectional area of said stream, a woven wire conveyor, a curved plate bridging a space between said nozzle or slice and said wire.

conveyor and means to adjust the length of path of said stream of paper pulp on said curved plate.

2. A paper making machine comprising in combination means to feed a stream of pap r pul under pressure, an outlet nozzle or slice predetermining the cross-sectional area of said stream,

spacebetween said nozzle or slice and said wire conveyor and means to adjust the said nozzle or slice angularly about the centr of a terminal guide roll for said wire conveyor.

4. A paper making machine comprising in combination means to feed a stream of paper pulp under pressure. an outlet nozzle or slice predetermining the cross-sectional area of said stream,

a woven wire. conveyor and apair of curved with a replates of diflering curvature to one another. disposed in tandem bridging a space between said outlet or slice and saidwire band conveyor.

5. A paper making machine comprising in combination means to feed a stream of paper pulp under pressure, an outlet nozzle or slice predetermining the cross-sectional area of said stream, a woven wire conveyor and a pair of curved plates or reversed curvature to one another, disposed in tandem bridging a space between said outlet or slice and said wire band conveyor.

6. A paper making machine comprising in combination means to feed a stream or paper pulp under pressure, an outlet nozzle or slice predetermining the cross-sectional area of said stream. a woven wire conveyor, a pair of curved plates of reversed curvature to one another, disposed in tandem bridgin a space between said outlet or slice and said wire band conveyor and means to adjust the edge or one plate peripherally along the surface or the other plate.

. 7. A paper making machine comprising in combination means to reed a stream of paper pulp under pressure, an outlet nozzle or slice predetermining the cross-sectionalarea 01' said stream, a woven wire conveyor, a curved plate bridging a space between said nozzle or slice and said wire conveyor and means to feed a stream of water below said st: earn of pulp as it meets said curved plate.

8. A paper making machine comprising in combination means to teed a stream of paper pulp under pressure, an outlet'nozzle or slice predetermining the cross-sectional area of said stream, a

woven wire conveyor, means to lead said stream oi pulp whilst exposed to the atmosphere first in 7 bination means to feed a stream or paper pulp under pressure, an outlet nozzle or slice predetermining the cross-sectional area oi said stream. a woven wire conveyor and means to guide said stream oi pulp leaving said nozzle or slice whilst exposed to the atmosphere flrst to a level below that o! the wire conveyor and then up to the level or said wire conveyor.

10. A paper making machine comprising in combination means to feed a stream of paper. pulp under pressure, an outlet nomle or slice predetermining the cross-sectional area of said stream,

a woven wire conveyor, a curved plate bri lns a space between said nozzle or slice and said wire conveyor and means to deflect part or the said stream of pulp when on said curved plate back :14; the supply of pulp stock to the said nozzle or ce. V 11. A paper making machine comprising in' combination means to feed a stream of paper pulp under pressure, an outlet nozzle or slice predetermining the cross-sectional area or said stream,

a woven wire conveyor, a curved plate bridging a space between said nozzle or slice and said wire conveyor and a pair or bames spaced inwardly from the edge or said curved plate to deflect the side portions or the stream of pulp on said curved plate back to the supply of stock to the said nozzle or slice.

12. A paper making machine comprising in combination means to feed a stream or paper pulp under pressure, an outlet nozzle or slice predetermining the cross-sectional area of said stream, a woven wire conveyor, a curved plate bridging a space between said nozzle or slice and said wire conveyor, a pair of baiiles spaced inwardly from the edges of said curved plate to deflect the side portions of the stream or pulp on said curved plate back to the supply of stock to the said nozzle or slice and means to adjust the width or the two streams of paper pulp so deflected.

ANDREAS THORSEN.