US2712154A

US2712154A - Apparatus for continuous production of artificial sponge cloth

Info

Publication number: US2712154A
Application number: US283869A
Authority: US
Inventors: Curt A J Lindquist
Original assignee: Celloplast AB
Current assignee: Celloplast AB
Priority date: 1952-04-23
Filing date: 1952-04-23
Publication date: 1955-07-05
Anticipated expiration: 1972-07-05

Description

1., .l'my 5, 1955 c, J, LINDQUIST 2,712,154

APPARATUS FOR CONTINUOUS PRODUCTION OF ARTIFICIAL SPONGE CLOTH Filed April 23, 1952 3 Sheets-Sheet l INVENTOR.

JIM MM i JTTORNEY 5, 1955 c. A. J. LINDQUIST 2,712,154

APPARATUS FOR CONTINUOUS PRODUCTION OF ARTIFICIAL SPONGE CLOTH Filed April 25, 1952 3 Sheets-Sheet 2 I l 'II I I I ILILIJI ATTOR NE 1 y 5, 1955 c. A. J. LINDQUIST 2,712,154

APPARATUS FOR CONTINUOUS PRODUCTION OF ARTIFICIAL SPONGE CLOTH Filed April 23, 1952 3 Sheets-Sheet 3 United States Patent APPARATUS FOR CONTINUOUS PRODUCTION OF ARTIFICIAL SPONGE CLOTH Curt A. J. Lindquist, Norrkoping, Sweden, assignor to Aktiebolaget Celloplast, Norrkoping, Sweden, a corporation of Sweden Application April 23, 1952, Serial No.- 283,869

Claims. (CI. 18-15 This invention relates to the art of producing artificial sponge cloth and constitutesan addition to or improvement upon the subject matter of my copending application Serial No. 152,092, filed March 27, 1950, now Patent No. 2,665,450.

; According to the disclosure of my said application, artificial sponge material consisting of' viscose with a mixture of Glaubers salt crystals or other-leachable poreforming. substance and fibers, generally of cotton or hemp, uniformly distributed therein, is extruded onto a traveling belt and is subjected to a .transversespreading action to bring it into the form of a web or sheet and then is subjected to a longitudinal rubbing or smearing action as it is carried along on thebelt, after which it is carried into a coagulating bath, being finally stripped from the belt after its regeneratior'i.v The-transverse and longitudinal smearing acts to orient a substantial portion of the fibers in the plane of the web and thus augments its strength. l v e In the main the present invention, constitutes detailed improvements upon the apparatus of my said patent for the purpose of increasing efiiciency and improving ;the product.

One feature of the invention resides in the character of the transversely reciprocatory spreader which acts at once upon-the rope or stream of material as it is deposited on the belt tospread it evenly across the belt and form it into a web of proper thickness. This web then is carried underneath a roller which is positioned to elfect a massaging or smearing action in a longitudinal direction on the web-and cause a longitudinal orientation of the fibers, and another feature of the invention resides in the character of the roller.

The friction incident to the smearing or rubbing action of the spreader and roller tends to elevate the temperature of the contacting surfaces and if uncompensated this heat will regenerate the celluloseto some extent at the surface and will produce a relatively hard surface skin which is objectionable since it interferes with the absorption of water and makes the cloth less pliable and soft. Toavoid this, the invention comprehends means for absorbing the heat resulting from the friction.

2 Also according to the invention the surface of'the roller is made corrugated by rather deep annular grooves so as to increase the surface area that engages the web, thereby augmentingthe orienting of the fibers and producing a. stronger article. If desired two' or more such rollers'may be arranged in tandem.

For some purposes it may be desirable partially or entirely to obliterate the longitudinal grooves formed in the web by the massaging rollers, and to accomplishthis theinvention contemplates a smooth-surface, driven roller disposed after the corrugated rollers and properly spaced drive 21 which maybe a Reeves ported on a base set on the floor, and a belt or chain 22 ICC high orientation of the fibers in that direction, and the other being smeared at an angle to the first, say, longitudinally, so as to get a very high orientation in that direction. Then the two layers are brought together before coagulation, in face contact with their treated faces contiguous and if desired may be subjected to a sq'eezing to assure cohesion.

This process may be batch or continuous. If con-' tinuous it is contemplated to employ two belts and extruding means for each belt. The layer on one belt will be laterally smeared by the spreader and the layer on the other belt will" be longitudinally smeared by one or more -grooved rollers. 'The bclts will be conducted so as to bring the two layers into face contact before entering the coagulating bath.

In order to get a maximum orienting effect in the transverse direction by the spreading action, the invention contemplates providing the spreader surface with transverse serrations, this being applicable to both the single layer and the double layer processes. Also, it has been found that the spreading action is enhanced by making the spreading surface cylindrically rounded or convex in transverse cross-section, as best seen in Figs. 3 and S.

The invention comprehends other features of construction which will be understood by reference to the illustifated embodiment which will now be described.

Fig. l is a plan of an apparatus embodying the invention and designed for carrying out the process.

Fig. '2 is a longitudinal sectional elevation taken on line 2' -2 of Fig. 1. v i

Fig. 3 is an enlarged sectional detail on the line 3'-3 ofFig. 2. v

Fig. 4 is a view similar to Fig. 2 of a modified construction of apparatus. Fig. 5 is an enlarged sectional detail on the line 5-5 of Fig. 4.

'6 is an enlarged sectional detail on line 6-6 of 1g.

7 is an enlarged sectional detail on line 7-7 of 1g. "In the construction of Figs. 1, 2 and 3, the sponge forming material is fed in a continuous stream from a hopper 11 onto an endless driven belt 12, and is first carried through acoagulating bath in a tank 17, the web being then stripped from the belt while the belt continues 'on through a cleaning and cooling bath in a tank 18.

The extruding mechanism for the hopper, the reciprocating-mechanism for the spreader-and the belt 12 are all driven from a prime mover consisting of a variable speed drive, shown as supdrived thereby operates a feed screw 23 through speed reduction pulleys or sprockets. The screw feeds the viscose with the Glaubers saltand fibers mixed therein in a thick narrow stream or rope' '24 onto the belt 12 into the path of the spreader.

The prime mover drives the belt roller'25 through belt or chain 26, from which roller the belt runs horizontally over a supporting or backing plate 27, rollers 28 and 2 9, thence down into the tank 17 under roller 30 and thence I :up over guide rollers 31 and 32, after which the Web is stripped from the belt and the belt continues on over roller 33 on the top of the tank 18, thence into the tank over

rollers

34 and 35 back to the roller 25.

The spreader is traversed by a compound screw 38 of well known construction having left and right hand threads. This screw bears in side frame members 39 and ,40 and is driventrom the prime mover zl-through', belt en gma or chain dri/e 41. The spreader 13 includes a wiping portion 42 and a supporting or carriage portion 43 attached to the top of the wiping portion and comprising a rectangular frame. Guide rods 44 and 45 extend through holes in the carriage 43 and across the belt and have their ends secured in the sides of the frame members 39 and 40 and thus serve to guide the spreader transversely. A shoe 46 is disposed on a bracket arm 47 on' the carriage portion and engages in the right and left hand thread on the screw 38. The rotation of the screw causes the shoe and hence the spreader to travel back and forth across the belt. I he wiper portion 42 is downwardly and forwardly curved from the frame hanger and terminates in a horizontal part at its trailing end, the leading part inclining E or curving upwardly. It will thereforebe seen that the rope of material 24 is first engaged by the oblique leading part and is gradually spread out laterally and comes eventually under the trailing horizontal end part which is properly spaced from the belt to determine the thickness of the web which is identified by the numeral 50. As explained in my said pending application, this lateral wiping or smearing causes an orientation of a substantial portion of the fibers, especially in the upper surface portion of the web, in the plane of the web and to a considerable extent in a transverse direction. If desired, and as will be later explained, the horizontal or trailing 'part of the spreader may have its surface transversely serrated, thereby increasing the surface area and enhancing the lateral orientation of the fibers.

The drive ratios are such that the speed of the spreader is several times that of the belt, and consequently each part of the web gets a considerable number of transverse strokes. This ratio is only diagrammatically indicated in the drawing. As a backing for the belt and for the web during this spreading, the plate 27 is supported immediately underneath the belt, being attached at its sides to the frame members 39 and 40, as by brackets not shown.

The friction incident to the massaging or rubbing of the sponge material during this spreading produces heat and tends to elevate the temperature of the viscose on'the surface. This heat will, if permitted, produce a surface coagulation and a skin effect which it is desirable to avoid.

To prevent this the invention contemplates means tocool the spreader and absorb the heat of friction. Asshown, the wiper part 42 is hollow and means are provided to circulate a cooling liquid in it, such as brine. For this purpose the cap on the top of the wiper is tapped for connection with two flexible hose members 51.

The web 50 as a result of the spreading is likely to 'extend over the edges of the belt, and means are provided to trim off the edges of the web into coincidence with the width of the belt. As shown these means comprise two rotary knives 52 on a transverse shaft 53 which bears at its ends in the side frames 39 and 40 and is driven at one end by a motor 54 which is supported on a plate 55 attached as by brackets to' the side frame 39. These knives are axially adjustable on the shaft and are fixed -by'set screws in shearing relation with the edges of the belt. This trimming action is illustrated in Fig. l.

The belt 12 may if desired have a pattern on its face to mold its counterpart in the under face of the web 50.

In the drawings the belt is shown as having'a grid on waffle design. Such design is purely for. ornamentation and improving the pliability and plays no substantial part in determining tensile strength."

This belt surface pattern is plainly shown'in transverse sectionin Fig. 3. As'there shown the trailing end of the wiper part of the spreader is transversely rounded so that its wiping surface is'cylindrical. This rounding or relieving of the sides of the wiping surface is carried on up into the inclined or leading portion which engages the material and produces distribution.

. The trimmed web is carried on by the belt underneath an even and uniform lateral the rollers 14, 15 and 16. These rollers are disposed in tandem in parallel relatiom'transversely of the belt and have hub extensions bearing in the side frames 39 and 40. They are properly spaced from the belt to engage the top surface of the traveling web, as will be described, and they are driven so as to rotate in the same direction as the web and ata speed somewhat in excess of that of the web so that they effect a'longitudinal rubbing or smearing action on the traveling web, thereby orienting a considerable portion of the fibers in a longitudinal direction. The plate 27 extends underneath rollers 14 and 15, and roller 16 is opposed by the belt guiding roller 28.

As shown, the rollers 14 and 15 have their peripheral surfaces corrugated by means of annular grooves and these rollers are so spaced from the belt that the ridges formed by the grooves enter the web surface substantially to the bottoms of the grooves. This gives a considerable smearing area for the surfaces and effects a high degree of fiber orientation. This produces a corrugated surface design for the web with the grooves and ridges running longitudinally and makes a pliable product with high tensile strength.

The use of two corrugated rollers is optional and one may be sufficient. Obviously if two or more are used it is desirable to have the grooves and ridges of the two rollers longitudinally aligned. Also, the use of a smooth roller 16 is optional and depends largely upon the character of product desired. If shallower grooves are desired or if it be desired to eliminate the corrugated effect in the sponge cloth altogether, the smooth surface roller can be set to accomplish this. In other words it is a smoothing'as well as an orienting or smearing roller.

Any suitable means may be provided to drive these rollers. As shown, a variable speed drive 58 is supported on'- a base set on the floor and a belt'or chain 59 connects the drive to a pulley on the hub of roller 14. A belt or chain 60 connects a second pulley on this hub to a-hub on the roller 15, and a belt or chain 61 connects a second policy in the hub of roller 15 with a pulley'on the hub of roller 16. Thus the three rollers are driven in the same direction and at the same speed by drive 58, which speed is adjusted to exceed the web speed.

To prevent formation of surface skin, these rollers are also cooled by the circulation of a refrigerating brine.

.. As shown, the rollers are hollow and their hubs are fixed .the .brine may be employed.

. ..Following.the formation of the web in the manner above described, the belt with the web attached is carried .around the roller 29 and down into the deep tank 17 which is shown as extending considerably below the floor line on which tank 18 sits. This tank 17 contains the usualcoagulating bath of hot acid 64 and the treatment .in this and the usual baths is continued until purification and regeneration are complete, when the web is stripped from the belt. -Diagrammatically this is shown as immediately following the emergence from tank- 17, the

finished web 50 being carried: off'to its intended destinationwhile the belt-12 travels. on through the washing and cooling liquid 65 in the tank 18;

- The apparatus of" Fig. 4 is designed to carry'out the two layer process, in which two layers are separately -forrned-and are stroked or smeared directions at an angle,'preferably a right angle, to each other. The two layers are then brought together face to face and at their c ontacting'surfaces into a single composite web. Ordinarily the'individual layers are'approximately of' half thickness so that together they'make a sponge cloth of the conventional thickness. The fact that the individual layers are relatively thin makes higher in proportio'n the orientation of the fibers in the plane of the web and principally in the direction of rubbing or stroking. The consequence is that the finished web is very strong in both the longitudinal and transverse directions.

As shown in Fig. 4, the extruding and spreading mechanisms are the same asin the apparatus of Figs. 1 to 3, except that the spacing of the spreader from the belt is somewhat less; By these means there is spread upon the belt a layer of sponge forming material which is designated 50a. As shown, the horizontal trailing end of the wiper portion 42 of the spreader 13 isprovided with transverse serrations 42a whichenhance the lateral orienting effect and incidentally leave the-surface of the layer Means presently to be described drive this belt at the same 4 speed as belt 12 and in a direction such that its lower flight moves with belt 12. The lower flight is disposed immediately over belt 12 and is spaced therefrom substantially the thickness of the finished composite web. The top flight of the belt 70 is backed by a plate 27a.

Extruding means are provided to deposit on the top flight of belt 70 a layer of sponge forming material which is designated 5%. This extruding means comprises a hopper 11a and a screw 23a driven by a belt or chain 22a from a source of power not shown. The nozzle 11b in this case is flat so that the material is deposited on the belt in a flat sheet of proper thickness and width, as shown in Fig. 6.

Overlying the belt 70 and properly spaced therefrom is a transverse grooved roller 77 similar to roller 14 which is driven in the direction of movement of belt 70 and at a somewhat greater speed. This roller bears in side frame members 39 and 40, and a pulley on one end is connected to roller 25, by belt 78, the ratio being properly proportioned. Roller 71 also bears in side frames 39 and and has a gear 79 with which gear 80 meshes. This gear 80 is driven from roller 77 by a belt 81. As shown the ratio of drive between the pulleys on gear 80 and roller 77 is l to 1, and since the diameter of roller 77 exceeds that of its pulley, its peripheral speed will exceed that at which the belt 70 is driven.

The layer b is rubbed or smeared by the roller 77 as it passes underneath and the fibers are largely oriented in a longitudinal direction. Then the two layers are brought around together as shown in Fig. 7, and are moved along together until over the tank 17 the material is stripped off from belt and is carried by belt 12 down between two rollers 83 and 84, the latter having its bearings in adjustable blocks so as to regulate the amount of squeeze that the rollers exert upon the web.

By passage between the rollers 83 and 84 the two layers are compressed together so as to be fully amalgamated into the web 50. The web is then stripped from the belt 12 and passes down into the coagulating bath in the tank 17 while the belt is directed over a roller 85 into the tank 18 and proceeds over the

rollers

34 and 35. as in the previous construction. The web 50 is conveyed down and up through the tank 17 around guide rollers 30 and the finished product is led over a roller 86 to a place for storage or other disposition.

The tank contains a washing and cooling liquid through which the belt 70 is conducted, as stated, preparatory to receiving again the continuously extruded layer of sponge forming material.

The two layers 50a and 50b are brought together with their treated faces contiguous, as shown in Fig. 7, and the belts are close enoughtogether to effect a preliminary amalgamation which is completed by the rollers 83 and 84. The fibers are largely oriented in each layer in the plane of the layer, with the fibers in the upper layer largely longitudinal and those in the lower layer largely transverse. This orientation is effective throughout each layer due to the fact that the layers are sufliciently thin to be influenced entirely through to the belt engaging surface by the smearing action on the opposite surface.

The belts in the apparatus of Fig. 4 are not shown as provided with a pattern, though of course they may have a pattern if desired.

It will be understood that while the illustrated mechanism represents one form in which the invention may be embodied, it is susceptible of structural and detail changes without departing from the principle and scope of the invention as defined in the following claims.

What is claimed is: "1; An apparatus for producing a continuous sheet of absorbing material comprising an endless belt, means to drive the belt, extruding meansfor depositing a stream .of material on to the belt which is substantially narrower than the belt, a transversely reciprocatory spreader disposed over the belt immediately in front of the extruding means and having its leading end spaced from the belt by the thickness of the sheet to be produced, means for reciprocating the spreader, a coagulating bath, means for guiding the belt through the bath, a roller having an annularly grooved surface disposed transversely over the belt between the extruding means and the bath and spaced with the bottoms of the grooves substantially the thickness of the sheet from the belt, and means to rotate the roller in the direction of movement of the belt at a peripheral speed exceeding the speed of the belt.

2. An apparatus as described in claim 1 together with means for cooling the spreader and the roller.

3. An apparatus as described in claim 1 in which the spreader has its trailing portion parallel with the belt and its leading portion divergent from the belt and its trailing portion is cylindrically convex.

4. An apparatus as described in claim 3 in which the said trailing portion is transversely serrated.

5. An apparatus for producing a continuous sheet of absorbing material comprising an endless belt, means to drive the belt, extruding means for depositing a stream of material on to the belt which is substantially narrower than the belt, a transversely reciprocatory spreader disposed over the belt immediately in front of the extruding means and having its leading end spaced from the belt by the thickness of the sheet to be produced, means for reciprocating the spreader at a speed greater than that of the belt, a coagulating bath, means for guiding the belt through the bath, a roller having an annularly grooved surface disposed transversely over the belt between the extruding means and the bath and spaced with the bottoms of the grooves substantially the thickness of the sheet from the belt, and means to rotate the roller in the direction of movement of the belt at a peripheral speed exceeding the speed of the belt.

6. An apparatus as defined in claim 1 together with trimming means disposed at both edges of the belt after the spreader and operative to remove material protruding over the edges of the belt.

7. An apparatus for producing a continuous sheet of absorbing material comprising an endless belt, means to drive the belt, extruding means for depositing a stream of material on the belt which is substantially narrower than the belt, a transversely reciprocatory spreader disposed over the belt immediately in front of the extruding means and having its trailing end spaced from the belt 7 5 through the bath, a roller having an annularly grooved surface disposed transversely over the belt and spaced therefrom with the bottoms of the grooves substantially the thickness of the sheet, means to rotate the roller in the direction of movement of the belt at a peripheral speed exceeding the speed of the belt, a roller having a smooth surface disposed over the belt after and parallel to the said grooved roller and spaced from the belt by substantially the thickness of the sheet, and means to rotate the smooth surface roller in the direction of movement of the belt.

8. An apparatus as described in claim 7 together with means for cooling the spreader and the grooved roller.

9. An apparatus for producing a continuous sheet of absorbing material comprising an endless belt, means to drive the belt, extruding means'for depositing a stream of material on the belt which is substantially narrower than the belt, a transversely reciprocatory spreader disposed over the belt immediately after the extruding means and spaced from the belt by the thickness of the sheet to be produced, a coagulating bath, means to guide the belt through the bath, a second endless belt disposed above the first belt and having its bottom flight guided over and parallel to the first belt between the spreader and the bath and spaced from the first belt, by substantially double the thickness of the sheet formed on the first belt, means for driving the second belt at the same speed as the first belt with its bottom flight traveling in the same direction as the first belt, means forextruding a second sheet of material on the top flight of the second belt, a roller having an annularly grooved surface dis,- posed transversely over the said top flight with the bottom of its grooves spaced from the belt by substantially the thickness of said second extruded sheet, and means to drive the roller in the direction of movement of said top flight at peripheral speed exceeding that of the second belt.

10. ,An apparatus as defined in claim 9 together with means for cooling the spreader and the roller.

References Cited in the file of this patent UNITED STATES PATENTS,

908,035 Ratignier et al Dec. 29, 1,133,548 Foltzer Mar. 30, 1915 1,354,018 Brock Sept. 28, 1920 1,961,316 Weingand June 5, 1934 1,983,531 Brandenberger et a1. Dec. 11, 1934 2,308,951 Novotny et al. Jan. 19, 1943 2,345,013 Soday Mar. 28, 1944 2,353,504 Schachar July 11, 1944 n2,576,3l7 Toulmin Nov. 27, 1951 3,665,450. Lindquist Jan. 12, 1954

Claims

1. AN APPARATUS FOR PRODUCING A CONTINUOUS SHEET OF ABSORBING MATERIAL COMPRISING AN ENDLESS BELT, MEANS TO DRIVE THE BELT, EXTRUDING MEANS FOR DEPOSITING A STREAM OF MATERIAL ON TO THE BELT WHICH IS SUBSTANTIALLY NARROWER THAN THE BELT, A TRANSVERSELY RECIPROCATORY SPREADER DISPOSED OVER THE BELT IMMEDIATELY IN FRONT OF THE EXTRUDING MEANS AND HAVING ITS LEADING END SPACED FROM THE BELT BY THE THICKNESS OF THE SHEET TO BE PRODUCED, MEANS FOR RECIPROCATING THE SPREADER, A COAGULATING BATH, MEANS FOR GUIDING THE BELT THROUGH THE BATH, A ROLLER HAVING AN ANNULARLY GROOVED SURFACE DISPOSED TRANSVERSELY OVER THE BELT BETWEEN THE EXTRUDING MEANS AND THE BATH AND SPACED WITH THE BOTTOMS OF THE GROOVES SUBSTANTIALLY THE THICKNESS OF THE SHEET FROM THE BELT, AND MEANS TO ROTATE THE ROLLER IN THE DIRECTION OF MOVEMENT OF THE BELT AT A PERIPHERAL SPEED EXCEEDING THE SPEED OF THE BELT.