US1986070A - Creping of paper in the longitudinal direction - Google Patents

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CREPING OF PAPER IN THE LONGITUDINAL DIRECTION Filed Dec. 16, 1932 UNITED STATES PATENT. OFFICE 1,986,070 canrmo or PAPER- m rnr. Lomn'ummr.

nmacrron HermannRoaenfelQGer-mauy Application Deoember 1c, 1932-, Serial No. 647,688 In Germany December 21, 1931 6 Claims. (01. 154-33) My invention relates to the creping of paper in the longitudinal direction.

It is an object of my invention to provide a method for creping long webs, such as. the webs 5 delivered from paper-making machines.

To this end, I perform the longitudinal creping of the webs progressively, for instance stepwise.

It has already been attempted to crepe paper in itslongitudinal direction only, or to crepe it in several directions but the methods which have been proposed for this purpose,'were not suitable for creping longitudinally long and continuous webs such as are delivered by paper-making machines, but at the most permit the creping of short strips or paper and not creping on a quantity-production basis. I

- It has also been attempted to crepe longitudinally continuous webs of paper by subjecting moist paper to an upsetting action for a considerable length. In this manner, suitable lonfeature of my method is that the creping or' creasing pressure is exerted only on a comparatively small portion of the paper at a time so that the width 'ofthe paper is reduced stepwise. Preferably, the paper, although it may be creped longitudinally only, is creped transversely as well by one of the usual methods, so that the product as finished has longitudinal as well as transverse creping and, as compared with paper creped in one direction only, is very resilient in all directions and suitable for purposes for which 40 paper with creping in one direction only could not be used on account of its insuflicient stretch.

In performing my method, I may proceed stepwise so as to form crease after crease until the web has been creased or creped'longitudinally all over its width. The creping may be performed by starting from one of the edges of the web and progressing toward the interior, or by starting from both edges, or by starting from the interior and progressing toward one, or both edges.

As mentioned, the gradual character oi! my method is important. For instance, consider a web which is 100 centimetres (about one yard) wide in its initial condition. During the first creping or creasing stage, the paper reduced for about in., i. e. to a width of 99 centimetres, in thesecond stage to 98 centimetres, and so on, stepwise, until the final width has been attained.

In the accompanying drawing, a machine for performing my method stepwise, and various 5 ways of operating the machine, are illustrated diagrammatically by way of example.

In the drawing:

Fig. 1 is a diagram of the machine,

Fig. 2 is a diagram of the operation illustrated for the machine in Fig. 1,

5 Fig. 3 is a diagram showinghow the operation is started from the interior of the web, and progresses toward both edges, 7

Fig. 4 shows the formation of several crease at a time,

Fig. 5 shows a web having longitudinal creases only,'and

Fig. 6 shows a web having longitudinal and transverse creases.

' Referring now to the drawing, and first to Figs. 1 and 2, P is a web of paper, and I, II n are the stages of creping. 1 is a creasing tool, and 2 is an abutting member. In the first stage I, the tool 1 and the member 2 form a crease 1' which extends in the longitudinal direction of the web, by moving them at right angles to the direction in which the web is fed.- The means for operating the tool 1 and the member 2 havenot been shown and may be of any suitable type. The first creasing operation reduces the width of the web for the amount. d. In the second stage II, the operation is repeated by forming a second crease 1 reducing 35 the width of the web again for the amount d, so that the total reduction is now 2d. The first crease 1 has moved inwardly for the amount d. In the third and fourth stages, III and IV, creases 1 and 1 are formed in the same manner and at the same pitch d, until finally in the stage n the crease 1 is formed at the distance mi from the edge of the web in its initial position. The web has now been creased for the desired width.

It will be understood that in the example-described the longitudinal creping of the web is efiected stepwise and by upsetting, but I am not limited to this particular type of progressive creping, nor am I limited to the use of upsetting tools as shown, but may use stamping, drawing, or any other type of mechanical, or even pneumatic tools. These variations have not been shown but will bereadily understood by any expert.

other.

Fig. 2 shows the progressive formation of the creases 1' etc. and it shows how the creping progresses gradually and step by step from the edge at the left over the width of the web. The straight lines at 1' etc. show the points of attack of the tools 1 and the members 2. The lines together make up a broken line extending longitudinally from one end of the web to the Instead of beginning with the creping operation at one edge, I may begin with both edges and gradually progress toward the interior of the web.

Another possibility is starting at the centre 01' the web as shown in Fig. 3, by forming a pair of creases 1 there, andprogressing toward both edges from the starting pair of creases.

Still another possibility is the formation of several creases per stage, as shown in Fig. 4 where three creases per stage are formed at L, L, etc. This reduces the time for creping a web of a given width.

There'should not be too many points of attack for the tools and members 1 and 2, nor should the points he pitched too closely as this leads to an undesirable excessive distortion of the paper.

The web may be creped while moving and whilestationary/ For instance, it is possible to perform the creping operation in cooperation with the formation of the web on a papermaking machine, and onthe still moist web. Moistening the web may also be desirable in the creping of a web which does not come directly from the paper-making machine.

I may also produce a pattern on the web by arranging the creping creases l'etc. at various points of the web on a given system. Or the creases may be omitted at certain points to obtain the pattern.

My invention further relates to the paper obtained by my method which, as shown in Fig. 5, may be creased longitudinally only, as at 1, or longitudinally and transversely, as shown at 1 and q in Fig. 6.

It is obvious that the comparatively short webs shown are illustrated merely by way of example and that in fact my method is applied to. long webs, its particular object being the treatment of long webs such as are delivered by paper-making machines, and the webs, as mentudinally comprising creasing said web across its edges and parallel to the plane of the paper web along a portion of its width only while continuously moving said web in a lengthwise direction and gradually extending the creasing across the width of the web until the paper is provided with creases throughout its width.

3. The method of creping paper webs longitudinally comprising creasing the web during its feed over a small distance transversely to its edges and parallel to the plane of the paper web while holding the remaining part of the web fast against transverse movement so that the web is longitudinally creped within said distance, and extending the creasing progressively to adjacent parts across the web.

4. The method of forming longitudinally creped paper webs by creasing the web in a stepwise manner in a plane parallel to the paper web across its width over a limited distance in each step and during the feed of the web in a lengthwise direction, said stepwise creasing beginning at the edges of the web and progressing inwardly.

5. The method of forming longitudinally creped paper webs by creasing the web in a stepwise manner in a plane parallel to the paper web across its width over a limited distance in each step and during the feed of the web in a lengthwise direction, said stepwise creasing beginning in the interior of the webs and progressing outwardly.

6. The method of creping paper webs as defined in claim 1, characterized by the fact that the creasing is started simultaneously at several different parts of the paper web.

HERMANN ROSEN'FELD.

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