JP2592365Y2 - Sheet wrinkle prevention device - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a wrinkle prevention device for preventing a sheet guided to a post-drying section from passing through a gate roll coater or a size press section from forming wrinkles on the entrance side of the post-drying section. Things.

[0002]

2. Description of the Related Art A paper machine generally comprises a wet section (a net section and a press section) and a dry section (a pre-dry section and a post-dry section).
As shown in FIG. 4, the drying section guides the sheet 2 that has passed through the pre-drying section 3 to the drying cylinder 6 of the post-drying section 5 through a gate roll coater 4 or a size press including a pair of rolls. However, there is a problem that wrinkles are easily generated in the sheet 2 at the entrance of the post-drying unit 5 by performing a process for giving printability and strength to the sheet 2 by the gate roll coater 4 or the size press. .

In order to solve such a problem, conventionally,
At the entrance side of the post-drying unit 5, an expander roll 7 having a crown as shown in FIG. 5 is provided so as to be rotatable around a curved core, and the sheet 2 is hung along the expander roll 7. , The central portion of the sheet 2 is curved so as to be higher, and by rotating the expander roll 7, the wrinkles generated in the sheet 2 are extended to eliminate the wrinkles. In addition, the expander roll 7 is configured to be covered with a Teflon cover to prevent contamination. 8 is a nozzle 9 which is linear in the width direction of the sheet
And an air turn bar that ejects air to guide the sheet 2 in a non-contact manner.

[0004]

However, in the above-mentioned conventional method, the effect of extending wrinkles generated on the sheet 2 by rotating the expander roll 7 is achieved. The Teflon cover has a life of one to two years, and the expander roll 7 with the crown is in contact with the sheet 2, so that there are many problems of abrasion and damage, and the surface is covered with the Teflon cover. However, the surface of the roll is easily soiled, and the surface of the sheet as a product may be damaged.

Accordingly, the present invention is intended to reduce the occurrence of sheet stains and troubles by making it possible to extend wrinkles generated on the sheet without directly contacting the sheet at the entrance of the post-drying section. Is what you do.

[0006]

According to the present invention, in order to solve the above-mentioned problems, an expander roll is arranged so that a sheet guided from a gate roll coater or a size press section is bent in a width direction at an entrance of a post-drying section. In the provided sheet wrinkle prevention device, instead of the expander roll, a duct having a plurality of divided and individually adjustable dampers attached to the inside on the radius side of the nozzle having a constant curvature is provided. Using an expander floater that is arranged and connected at intervals and the other end of the duct is connected to an integral header, the sheet is bent in the width direction in a non-contact state by wind pressure ejected from a nozzle. The configuration is as described above.

The number of nozzles may be one or more.

[0008]

When compressed air is supplied from the integrated header to the nozzle through a plurality of ducts, the sheet ejected from the curved nozzle is curved and deformed in the width direction and the wrinkles are extended. At this time, if the pressure of the duct in the central portion of the nozzle is adjusted to be high, the air pressure ejected from the central portion of the nozzle increases, so that the central portion of the sheet can be greatly bent without contacting the nozzle.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIGS. 1 to 3 show an embodiment of the present invention. As shown in FIG. 4, after a number of drying cylinders 6 are arranged from a gate roll coater or a size press section 4 in a drying section 1. FIG. The wet paper sheet 2 guided to the drying unit 5 is subjected to a process of giving printability and strength by a gate roll coater 4 or a size press, and wrinkles generated on the sheet 2 due to this process are removed later. In a configuration in which the sheet 2 is removed by bringing the sheet 2 into contact with the expander roll 7 at the entrance of the drying unit 5, wrinkles generated in the sheet 2 are removed instead of the expander roll 7.
, An expander floater 10 that removes the non-contact portion is used.

In detail, the expander floater 1
0 is as shown in FIG. 2A viewed from the flow direction of the sheet 2,
As an example, a nozzle 1 curved to have a constant curvature
1, an integral header (integral header) 12, and a plurality of ducts 13 connecting the integral header 12 and the nozzle 11.
A plurality of ducts 13 are connected to the inside of the curved nozzle 11 at appropriate intervals, divided into blocks, the nozzles 11 are partitioned by partitioning plates 23 corresponding to the respective ducts 13, and The other end is aligned and the integrated header 12
The integrated header 12 is connected integrally to a fan 17 via a duct 16 having a damper 15 in the middle, and a fan 17
From the integrated header 12 to each duct 1
3 to the nozzle 11 so that the integrated header 1
The total amount of air supplied to the nozzle 2 is controlled by a damper 15 in the middle of the duct 16.
Is controlled individually in each duct 13.

Further, as shown in FIG. 2B viewed from the side in the flow direction of the sheet 2, the nozzles 11 are opened in the width direction of the sheet 2 and arranged in the flow direction of the sheet 2. And the edge plates 25 and 2 of the opening 24 are provided.
A slit forming member 26 extends from one end of the opening 24 to the other end in the width direction of the sheet 2 in parallel with the edge plate 25 between the five. The slit forming member 26 is connected and locked to the edge plate 25 of the opening 24 by stoppers 27 arranged at appropriate intervals in the width direction of the sheet, and the slit 28 is formed between the slit forming member 26 and the edge plate 25 of the opening 24. Is formed. The stopper 27 has a function of connecting and locking the slit forming member 26 to the edge plate 25 of the nozzle opening 24 and keeping the width of the slit 28 constant over the entire length of the sheet 2 in the width direction. The pressurized air supplied from the duct 13 to the nozzle 11 collides with the sheet 2 through the slit 28 to cause the sheet 2 to float.

The duct 1 of the expander floater 10
3 is a duct 13 as partially shown in FIG.
A pressure controller 18 for detecting the wind pressure in the inside is provided, and a hydraulic cylinder 19 for controlling the damper 14 to adjust the amount of air entering the duct 13 from the integrated header 12 is provided. A switching valve 21 provided in a pipe connecting the supply pump 20 to
The configuration is such that switching can be performed by a command from a controller 22 that inputs a detection value from the pressure controller 18.

The expander floater 10 having the above configuration
Is installed on the inlet side of the drying cylinder 6 of the post-drying unit 5 at the same position as the conventional expander roll 7 shown in FIG. In this case, the nozzle 11 which is curved and whose central part is projected is installed so as to be parallel to the width direction of the sheet 2, and the integrated header 12 is provided from the fan 17 via the duct 16 and the damper 15.
Supply air into the interior. As a result, air is supplied from the integral header 12 to each duct 13 via each damper 14,
Further, air is supplied from each duct 13 to the nozzle 11 for each block by each duct 13.
Air is spouted from 1.

The sheet 2 guided from the gate roll coater 4 or the size press to the post-drying section 5 through the air turn bar 8 is not contacted by the wind pressure blown from the nozzle 11 of the expander floater 10 and has a width as shown in FIG. The central part of the direction extends and is curved. As a result, the wrinkle-prone sheet 2 is stretched, and the wrinkle-free sheet 2 is dried in the post-drying unit 5.

In the above, the interval between the nozzle 11 and the sheet 2 is maintained at a predetermined interval by controlling the air volume with the damper 15 in the middle of the duct 16.
The wind pressure supplied from each duct 13 to the nozzle 11 is
It can be controlled by individually detecting the wind pressure in the duct 13 by the pressure controller 18 and operating the switching valve 21 to adjust the damper 14.
In view of the fact that the central portion of the sheet 2 in the width direction is extended and bent to approach the nozzle 11 as shown in (A), the wind pressure of the duct 13 located at the central portion is the wind pressure of the other duct 13. Adjust it to be higher.

In the above embodiment, the case where the nozzle 11 is bent to a certain curvature to make the curvature constant has been described.
A bending device can be provided at both ends of the device 1 so that the device can be bent to an arbitrary curvature. By doing so, the nozzle 11 can be bent to an appropriate curvature,
There is an advantage that it can be a sheet without wrinkles,
In the above embodiment, the description has been given with reference to FIG. 2B in the case of three nozzle openings 24. However, the number of nozzle openings 24 is not limited to three, but is suitable for the radius of curvature of the nozzle 11. In addition, although the above embodiment has been described in connection with the case where the air turn bar is provided, it is needless to say that the present invention can be applied to the case where the air turn bar is not provided.

[0018]

As described above, according to the sheet wrinkle prevention device of the present invention, the sheet guided to the post-drying section via the gate roll coater or the size press is fed to the post-drying section at the center in the width direction at the entrance. An expander floater for extending and bending is installed, and the sheet can be bent in a non-contact manner on the surface of the sheet so that wrinkles can be extended, so that the following excellent effects can be obtained. . (i) Since the nozzle of the expander floater is bent to the required curvature, and the wind pressure of a plurality of ducts connected to the nozzle is individually controlled,
The sheet can be bent without wrinkles while maintaining a constant distance between the nozzle and the sheet. (ii) Since the sheet is in a non-contact state with the nozzle, the life is longer than that of the conventional expander roll, and the abrasion,
There are few troubles such as damage. (iii) Since the sheet is not in contact with the nozzle, there is no danger of soiling the sheet due to stains on the floater or damaging the sheet.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an embodiment of the present invention.

FIGS. 2A and 2B show details of the expander floater according to the present invention, wherein FIG. 2A is a detailed view of the expander floater of FIG. 1 viewed from the flow direction of the sheet 2, and FIG. 2B is a view of the expander floater of FIG. FIG. 3 is a detailed view as seen from a side surface of the seat 2.

FIG. 3 is a diagram showing details of a part III in FIG. 2 (A).

FIG. 4 is a schematic diagram using a conventional expander roll.

FIG. 5 is a schematic view of a conventional expander roll.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Drying part 2 Sheet 3 Front drying part 4 Gate roll coater 5 Rear drying part 6 Drying cylinder 10 Expander floater 11 Nozzle 12 Integrated header 13 Duct 14, 15 Damper 16 Duct 17 Fan

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A 5-89496 (JP, U) JP-A 5-89497 (JP, U) JP-A 3-92797 (JP, U) (58) Survey Field (Int.Cl. ⁶ , DB name) D21F 1/40 B29C 67/00 D21F 1/42

Claims (1)

(57) [Scope of request for utility model registration] 1. A plurality of ducts each having a plurality of adjustable dampers attached to the inside of a nozzle having a constant curvature on the side of a radius of curvature of a nozzle are arranged at predetermined intervals and connected to each other. An expander floater having a configuration in which the other end is connected to an integral header, and a post-drying unit that bends the sheet guided from the front drying unit to the post-drying unit through a gate roll coater or a size press at the center in the width direction. A sheet wrinkle prevention device, which is installed at an entrance.