KR940005201B1 - Apparatus and method for continuously drying both sides of paper web - Google Patents

Abstract

No content.

Description

[Name of invention]

Apparatus and method for continuously drying both sides of paper web

[Brief Description of Drawings]

Side elevational view of a BEL RUN type drying compartment of the prior art showing four groups of first drying rollers for drying the first surface of the paper web of FIG.

FIG. 2 is a side input view of a bell-shaped drying structure of the present invention showing a means for conveying a web without an open draw from a first felt to a second felt.

FIG. 3 is an enlarged side elevation view of FIG. 2 showing the web conveying section in detail such that the opposite side of the web is in physical contact with the subsequent group of drying rollers.

Like parts in FIGS. 1 to 3 denote like reference numerals.

Detailed description of the invention

Background of the Invention

Technical Field of the Invention

The present invention relates to an apparatus for continuously drying both sides of a paper web. More specifically, it relates to a BEL RUN type drying unit in which the first drying unit dries one side of the web, and then the subsequent drying unit dries the opposite side of the web.

[Initiation of information]

In the conventional dryer section of the bell-type structure, the single felt part may be composed of four groups or less of rollers. Typically, because the paper web is always supported by the dryer felt, the group includes drying rollers and suction rollers that do not provide open draw in their structure. As the web progresses from one group of dryers to the next group of dryers, only the same side of the web is always provided to the continuous drying roller. However, in order to expose the opposite side of the web to the drying roller continuously, it was necessary in the past to transfer the unsupported web to the subsequent dryer felt.

A so-called single felt dryer is subsequently used, which is adapted to continuously pass around the upper and lower dryer drums in a curved path in which the joint run of the web and felt is wrapped. This arrangement provides a felt support for supporting the web between successive upper and lower dryer dreams, but the result is that as the felt is sandwiched between the web and the drying roller, the drying of the web is greatly reduced while passing around the lower drying roller. As a result, the lower dryer drum will be excessive. Moreover, such single felt portions still do not dry both sides.

The problem with the above described bellows structure and single felt dryer is that only one side of the web is dried as the web passes through several dryers of the first group. As a result, this arrangement allows both sides to differ in surface tension and properties. Additionally, when sheet paper is required in which both sides of the sheet must have similar properties, it is a problem that the smoothness of each side of the web is different. In addition, warping and nonuniformity corresponding to moisture changes is a problem with the dryer section.

It is an object of the present invention to insert a first felt between the felt during the passage of the web and to allow the opposite side of the web to be in physical contact with the heating surface of the subsequent drying roller while the web is moving around the subsequent drying roller. And by providing a web conveying section defined by a second felt and overcoming the problems associated with bellows and other single-felt dryer section structures.

Accordingly, it is a first object of the present invention to provide an apparatus which overcomes the above inadequacies of the prior art and makes an important and obvious contribution to the field of paper drying technology.

Another object of the present invention is to provide a method for continuously drying both sides of the web by the first plural drying roller physically contacting the first side of the web and the second plural drying roller physically contacting the second side of the web. One felt is a continuous loop, which alternately extends in a curve wrapped past the drying roller and the suction roller, and the second felt is a continuous loop which alternately extends in a curve wrapped past the drying roller and the suction roller.

Another object of the present invention includes guiding the joint drive of the web and the first felt around the first drying roller such that the web is sandwiched between the first felt and the first drying roller to heat the first side of the web. It is to provide a method for continuously drying both sides of the web to be successively alternately.

The cavity drive is then guided around the first suction roller such that the first felt is sandwiched between the web and the first suction roller. The second felt is guided from the second guide roller around the second suction roller so that the web supported by the first felt is defined by the first felt and the second felt defining a web feed section therebetween. Guided to the web conveying section while being disposed between the second felts, the web coming out of the web conveying section is drawn around the second suction roller so that the second felt is disposed between the web and the second suction roller, and then the web and The co-drive of the second felt is directed around the second drying roller so that the web is sandwiched between the second felt and the second drying roller so that the web heats the second surface.

Other objects and advantages of the present invention will become apparent to those skilled in the art from the detailed description taken in conjunction with the accompanying drawings and claims.

Summary of the Invention

The present invention relates to an apparatus and a method for continuously drying both sides of a paper web.

The apparatus includes a first drying roller and the web extends around a circumferential portion of the roller. The first felt extends around a portion of the first drying roller so that the web is sandwiched between the first felt and the first drying roller to heat the first surface of the web. The first suction roller has a rotation axis spaced parallel to the rotation axis of the first drying roller and is disposed downstream from the first drying roller. The first felt and the web extend around the circumferential portion of the first suction roller such that the first felt is sandwiched between the first suction roller. The first guide means guides the first felt away from the first suction roller, and the second suction roller has a rotation axis spaced in parallel with the rotation axis of the first suction roller and is disposed adjacent to the first suction roller. The second felt extends around the second suction roller and the second guide means guides the second felt toward the second suction roller so that the web can be interposed between the felt in the course of passing through the feed compartment. Define a web feed section between two felts. The second drying roller is disposed downstream with respect to the second suction roller while having a rotation axis parallel to the rotation axis of the second suction roller so that the web is sandwiched between the second felts so that the second side of the web is heated by the second drying roller. Be sure to

In a more specific embodiment of the invention, the first felt is a continuous loop extending in a sine curve path which alternately passes through the first drying roller and the suction roller.

In addition, the second felt is a continuous loop extending in a wrapped curve passing through the second drying roller and the second suction rollers such that the first drying roller is in physical contact with the first surface of the web and the second drying roller is physically In contact with the second side of the web, both sides of the web may be continuously dried.

The first guide means includes a first guide roll for guiding the first felt, and the second guide means includes a second guide roll for guiding the second felt.

The present invention also includes a method for the paper web to alternately successively dry both sides, the method between the first felt and the first drying roller by guiding the joint drive of the web and the first felt to the first drying roller. The web is fitted so that the first side of the web is heated. Thereafter, the joint drive of the web and the first felt is guided to the first suction roller so that the first felt is sandwiched between the web and the first suction roller. The first felt is then guided around the first guide roll, and the second felt is guided from the second guide roll around the second suction roller such that the first and second felt define a web feed section therebetween, thereby The web supported by one felt is guided to the web conveying section so that the web is disposed between the first felt and the second felt. The web from the web conveying section is drawn around the second suction roller such that the second felt is disposed between the web and the second suction roller. The joint drive of the web and the second felt then moves around the second drying roller such that the web is sandwiched between the second felt and the second drying roller to heat the second side of the web.

While the invention has described certain embodiments in the following description, it will be apparent to those skilled in the art that modifications and variations can be made in the invention without departing from the spirit and scope as defined in the appended claims.

Detailed Description of the Drawings

1 is a side elevational view of a conventional bell-shaped drying unit comprising groups A, B, C and D for drying the paper web 1. As shown in FIG. 1, the web 1 is guided in a curve wrapped around a plurality of drying rollers 2, 2 ′ and 2 ″ and suction feed rollers 3, 3 ′ and 3 ″. As the web alternately moves past the drying roller and the absorbing rollers 3, 2, 3 ', 2', 3 "and 2", the first felt 4 has a plurality of guide rollers 5, 5 ', 5 ", 5 " and 5 " " to support the web 1 while moving in a loop. The second group B is provided with the drying rollers 6, 6 'and 6 "and the suction rollers 7, 7' and 7" alternately arranged therebetween, whereby the second felt 4 ' A sine curve is made to loop around the suction roller and the drying rollers 7, 6, 7 ', 6', 7 "and 6". As the web 1 supported by the drying roller 2 "rotates adjacent to the second felt 4 ', the web 1 is not supported by the felt 4, whereby the web 1 It is conveyed around the second felt 4 'and the suction roller 7. However, as shown in FIG. 1, only the same side of the web 1 is dried rollers 2, 2', 2 ", 6, 6 'and 6 "), so that the same surface 8 is dried.

The present invention, as shown in Figure 2, while the web 1A is reversed from the first drying unit (A1) to the second drying unit (B1), while the web passes through the first portion (A1), The first surface 8A of the web 1A is in physical contact with the rollers 2A, 2A 'and 2A ". In the second drying part B1, the second surface 9 of the web 1A is It is in physical contact with the heating surfaces of the drying rollers 6A, 6A 'and 6A ".

FIG. 3 is an enlarged partial view of the conveying section of FIG. 2 to show how the web 1A is reversed. More specifically with respect to FIG. 3, the apparatus 10 for continuously drying both sides 8A and 9 of the paper web 1A comprises a first drying roller 2A ″, the circumferential portion of the roller. The first felt 4A extends around a portion of the first drying roller 2A "', and the web 1A extends the first felt 4A and the first drying roller 2A"'. And the first surface 8A of the web 1A. The first suction roller 3A "'is arranged downstream with respect to the 1st drying roller 2A"'. The roller 3A "'has an axis of rotation spaced in parallel with respect to the axis of rotation of the first drying roller 2A". The first felt 4A and the web 1A are the circumference of the first suction roller 3A ". It extends around a portion so that the first pet 4A is sandwiched between the web 1A and the first suction roller 3A ". As shown in FIG. 2, the first guide means 5A is a first felt. Guide 4A to be separated from the first suction roller 3A "'. The second suction roller 7A is disposed adjacent to the first suction roller 3A "', and the second suction roller 7A has a rotation axis spaced in parallel with respect to the rotation axis of the first suction roller 3A"'. Equipped. The second felt 4A 'extends around the second suction roll furnace 7A and as shown in FIG. 2, the second guide means 12 moves the second felt 4A' to the second suction roller 7A. And the first and second felts 4A and 4A 'respectively define a web feeder 14 therebetween so that the felt 4A and 4A while the web 14 passes through the feeder 14, respectively. It will be sandwiched between '). The second dry ruler 6A has a rotation axis parallel to the axis of rotation of the second suction ruler 7A and is disposed downstream of the second suction roller 7A so that the web 1A has a second felt 4A '. And the second drying roller 6A are inserted to heat the second surface 9 of the web 1A.

As shown in FIG. 2, the first felt 4A includes a drying roller and a suction roller 3A, 2A, 3A ', 2A', 3A ", 2A", and ( Since it is an extended loop extending in a sine curved path alternately passing through 3A "'), this drying roller is brought into physical contact with the first surface 8A of the web 1A, and the plurality of second drying rollers 6A, 6A 'and 6A "are in physical contact with the second side 9 of the web 1A to continuously dry the other side of the web 1A.

More specifically, the first guide means comprises a first guide roller 5A for guiding the first felt 4A, and the second guide means is a second guide roller for guiding the second felt 4A ". And (12).

In operating the present invention both sides 8A and 9 of the paper web 1A are successively dried by the following process steps:

1. The joint drive of the web 1A and the first felt 4A is guided around the first drying roller 2A ", as shown in FIG. 3, so that the web 1A is the first felt 4A. ) And the first drying roller 2A "to heat the first surface 8A of the web 1A.

2. Thereafter, the joint drive of the web 1A and the first felt 4A is guided around the first suction roller 3A "so that the first felt 4A is guided by the web 1A and the first suction roller 3A. "').

3. The first felt 4A is guided around the first guide roll 5A, and the second felt 4A 'is guided from the second guide roll 12 around the second suction roll 7A so that the first felt 4A is guided around the first guide roll 5A. The felt 4A and the second felt 4A 'each define a web feeder 14 therebetween, so that the web 1A supported by the first felt 4A is guided to the web feeder 14. And are disposed between the first felt 4A and the second felt 4A ', respectively.

4. The web 1A emerging from the web conveying portion 14 is drawn around the second suction roller 7A so that the second felt 4A 'is disposed between the web 1A and the second suction roller 7A. .

5. Thereafter, the joint drive of the web 1A and the second felt 4A 'is oriented around the second drying roller 6A so that the web 1A is the second felt 4A' and the second drying roller 6A. The second surface 9 of the web 1A is heated by being sandwiched between the two surfaces.

The present invention provides a simple device for conveying a web between continuous groups of dryers in a BEL RUN structure so that both sides of the web can be dried, thereby making paper products with uniform surface properties, surface tension and smoothness without distortion. Can be provided.

In the first group of dryers, the suction roller is arranged below the drying roller, while in the second group of dryers, the suction roller is arranged above the drying rollers. This structure provides the simple web feed described above so that the web can be transported from the first felt to the second felt.

Claims (10)

A plurality of first drying rollers 2A, 2A ', 2A "rotating in the first direction 20 to dry the first surface 8A of the web 1A and opposite the first direction 20 A first row having a plurality of first suction rolls 3A ', 3A "disposed in the second direction 22 and disposed between adjacent drying rollers of the first drying rollers 2A, 2A', 2A"; Drying section (A): first dry felt means (4A) for conveying the web (1A) in a curved curve path along the drying rollers (2A, 2A ', 2A ") and suction rollers (3A', 3A"); Passes through a plurality of second drying rollers 6A, 6A ', 6A "rotating in the second direction 22 to dry the second surface 9 of the web 1A, wherein the second drying rollers 6A, 6A ', 6A ") disposed downstream between said first drying section A1 having a plurality of second suction rollers 7A', 7A" disposed between adjacent drying rollers and rotating in the first direction 20 A second line drying unit B1 disposed in the line; Second dry felt means (4A ') for conveying a web (1A) in a curved path enclosed along said second drying rollers (6A, 6A', 6A ") and said second suction rollers (7A ', 7A"); And a web 1A between the first felt means 4A and the second felt means 4A 'such that a controlled transfer of the web 1A is made from the first felt means 4A to the second felt means 4A'. Guide means 3A "'for guiding the first felt means 4A and the second felt means 4A' in close proximity to each other between the first and second drying parts A1 and B1 to fit the 5A, 7A, 12; Web (1A) drying apparatus comprising a. 2. The first suction roller according to claim 1, wherein the means for guiding the first felt means and the second felt means in close proximity to each other are disposed downstream of the plurality of first drying rollers 2A, 2A ', 2A ". 3A "'and the second suction roller 7A disposed downstream with respect to the first suction roller 3A"', the first suction roller 3A "'is connected with the web 1A. First felt means 4A such that the web 1A can be held in contact with the first felt means 4A while the first felt means 4A pass together around the first suction roll 3 "'. The first suction roller 7A is operable to apply a vacuum to the web 1A through the first suction roller 7A. The first suction roller 7A is configured to allow the web 1A to be second felt when the first felt means 4A is separated from the web 1A. It is operable to apply a web 1A vacuum through the second felt means 4A 'so that it can be held in contact with the means 4A', whereby the second felt means 4A 'and the web 1A Web when passing together around the second suction roller 7A A web drying apparatus, characterized in that 1A can be conveyed from the first felt means 4A to the second felt means 4A without being open drawn. 3. The second direction (22) according to claim 2, having a plurality of third drying rollers (2A ") which rotate in the first direction (20) to further dry the first surface (8A) of the web (1A). A third drying section (C1) disposed downstream of said second drying section (B1) having a plurality of third suction rollers disposed between adjacent drying rollers of said third drying roller; A third drying felt means for conveying 1A) in a curved curve path along the plurality of third drying rollers and the plurality of third suction rollers, disposed downstream of the third drying portion A1, in a second direction ( A plurality of fourth drying rollers rotating in the first direction 20 and disposed between adjacent drying rollers of the plurality of fourth drying rollers and rotating in the first direction 20. A fourth row drying unit D1 for drying the second surface 9 of 1A; the plurality of fourth drying rollers and the plurality of fourth suction rolls of the web 1A. A fourth dry felt means for conveying in a curved path enclosed along the rollers; the second felt means 4A for enabling further controlled conveyance of the web 1A from the second felt means 4A 'to the third felt means. Guide the second felt means 4A 'and the third felt means close to each other between the second and third drying parts B1 and C1 so that the web 1A is sandwiched between') and the third felt means. Additional guiding means 7 "'; And the third drying part and the third drying part so that the web 1A is sandwiched between the third felt means and the fourth felt means in order to enable another controlled transfer of the web from the third felt means to the fourth felt means. An additional guiding means for guiding the third and fourth felt means close to each other between the four drying parts C1 and D1, and further guiding the second and third felt means close to each other; And an additional means for guiding said third and fourth felt means in close proximity to each other comprises a pair of suction rollers disposed adjacent to each other. The method of claim 2 or 3, wherein the first felt means 4A and the web 1A extend around a portion of each drying roller of the plurality of first drying rollers 2A, 2A ', 2A ". The first surface 8A of the web is heated by the ebb 1A being sandwiched between each roller of the plurality of first drying rollers 2A, 2A, 2A ″ and the first felt means 4A; The means for guiding the first and second felt means 4A, 4A 'in close proximity to each other is a first guide means for guiding the first felt means 4A away from the first suction roll 3A "'. 5A, and the first and second felts 4A and 4A 'form a web feeder 15 therebetween so that the web passes through the web feeder 14 and the first felt and the second felt. A second guide means (12) for guiding said second felt means (4A) toward a second suction roller (7A) so as to be disposed therebetween; said first felt means (4A) having a web (1A) and a first The first felt means 4A and the web 1A extend around a portion of the circumference of the first suction roller 3A "'so as to be sandwiched between the suction rollers 3A"'; The second felt means 4A 'and the web 1A extend around the second suction roller 7A such that 4A' is sandwiched between the web 1A and the second suction roller 7A; A plurality of second drying rollers 6A, 6A ', 6A "are attached to the second suction roller 7A. Disposed downstream of the second drying roller 6A, 6A ', 6A ", wherein each drying roller has a rotation axis parallel to the rotation axis of the second suction roller 7A so that the web 1A Web drying apparatus characterized in that it is sandwiched between each drying roller of the drying rollers 6A, 6A, 6A "and the second felt means 4A 'so that the second surface 9 of the web 1A is heated. . The method of claim 1, wherein the first felt means comprises a drying roller of the plurality of first drying rollers 2A, 2A ', 2A "and a plurality of first suction rollers 3A', 3A". Each drying roller of the plurality of first drying rollers 2A, 2A ', 2A "is formed by including a single felt 4A of continuous loops extending in a curved path alternately wrapped between suction rollers of Is in physical contact with the first surface 8A of the second felt means, the second felt means comprises a plurality of second drying rollers 6A, 6A ', 6A "and a plurality of second suction rollers 7A', 7A". Each drying roller of the plurality of second drying rollers 6A, 6A ', 6A "is formed by the inclusion of a single felt 4A' of continuous loops extending in a curved path alternately wrapped between the suction rollers of Physical contact with the second surface (9) of (), whereby both sides of the web (1A) are continuously dried. 5. The method of claim 4, wherein the first guide means comprises a first guide roll 5A for guiding the first felt means 4A; The second guide means comprises a second guide roll (12) for guiding the second felt means (4A '). 4. A plurality of suction rollers 3A ', 3A "; 7A', 7A" according to any one of the preceding claims, wherein the plurality of drying rollers 2A, 2A ', 2A "; 6A, 6A', 6A ") are alternately arranged on the upper and lower portions of the web drying apparatus. First row drying unit A1 having a plurality of first drying rollers 2A, 2A ', 2A "rotating in the first direction 20 to dry the first surface 8A of the web 1A. Guiding the web 1A to the furnace (the first drying unit A1 rotates in a second direction 22 opposite to the first direction 20 and the first drying rollers 2A, 2A ', 2A). &Quot; a plurality of first suction rolls 3A ', 3A " disposed between adjacent drying rollers of "); and the web 1A and the first drying felt means 4A are formed by the drying rollers 2A, 2A', 2A ") and continuously conveying the web 1A together with the first felt drying means to proceed in a curved path along the suction rollers 3A ', 3A"; downstream to the first drying part A1. Second row drying with a plurality of second drying rollers 6A, 6A ', 6A "disposed in and rotating in the second direction 22 to dry the second surface 9 of the web 1A. Guiding the web to the portion B1 (the second drying portion B1 is the adjacent drying of the second drying rollers 6A, 6A ', 6A "). Having a plurality of second suction rollers 7A ', 7A "disposed between the rollers and rotating in the first direction 20; A web 1A and a second dry felt means 4A 'are curved paths along the plurality of second drying rollers 6A, 6A', 6A "and the plurality of second suction rollers 7A ', 7A". Continuously conveying the web 1A with a second dry felt means 4A 'to proceed to; And a web 1A between the first and second felt means 4A, 4A 'to regulate the transfer of the web 1A from the first felt means 4A to the second felt means 4A'. Guiding the first and second felt means (4A, 4A ') in close proximity to each other between the first and second drying units (A1, B1) so that the fitting can be fitted. 9. A method according to claim 8, between the first felt means 4A and each of the plurality of first drying rollers 2A, 2A ', 2A "for heating the first surface 8A of the web 1A. Guiding joint driving of the web (1A) and the first felt means (4A) around each of the plurality of first drying rollers (2A, 2A ', 2A ") such that the web (1A) is fitted into the web; The web 1A and the first felt means (1) around the first suction roller 3A "'so that the first felt means 4A can be fitted between the web 1A and the first suction roll 3A"'. Guiding the joint drive of 4A); Guiding the first felt means (4A) around a first guide roller (5A); The web conveying portion 14 is supported by the first felt means 4A by the first felt means 4A and the second felt means 4A 'defining the web conveying portion 14 therebetween. Guides the second felt means 4A 'from the second guide roller 12 around the second suction roll 7A so as to be guided by the first and second felt means 4A, 4A'. Making; Drag the web 1A from the web conveying portion 14 around the second suction roll 7A so that the second felt means 4A 'can be fitted between the web 1A and the second suction roller 7A. Entering step; And thereafter, between the second felt means 4A 'and each of the plurality of second drying rollers 6A, 6A', 6A "for heating the second surface 9 of the web 1A. Directing the co-drive of the web 1A and the second felt means 4A 'around each drying roller of the second drying rollers 6A, 6A', 6A "so that the web 1A is fitted. Web drying method characterized in that. 10. The method according to claim 8 or 9, comprising directing the web (1A) to further line drying units (C1, D1) to further dry both sides (8A, 9) of the web (1A). Web drying method characterized in that.

Images