JPH0725478B2 - Folding device for polymerized strips - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a folding device for folding a polymerized strip in two in a longitudinal direction.

[0002]

2. Description of the Related Art Conventionally, when a number of strips of paper are passed over a folded plate and folded in two while running, the back side (fold side) and the edge side of the folded folded strips are nipped by an nip roll. It has been pinched and folded.

[0003]

However, in the above-described folding device for a polymerized strip, the polymerized strip causes a runout in a direction orthogonal to the feeding direction, causing a phenomenon of so-called meandering travel, and it has good compatibility with the folding plate. And the linearity of the crease line is impaired, which causes poor folding, and the appearance of a linear indentation that clearly appears in the appearance is formed in the part where the double-folded polymer strip contacts the inner edge of the nip roll. Have a damaging problem.

[0004]

DISCLOSURE OF THE INVENTION The present invention is intended to solve the above problems, and as a means therefor, the spine nip roll pressure in the above-mentioned polymerized belt folding device is larger than the edge nip roll pressure. The back side nip roll and the edge side nip roll have an arcuate surface that reduces the inner peripheral surface of the inner peripheral surface toward the inside. Is formed.

[0005]

[Function] In the case of the folded double-faced strip, the feeding is promoted on the back side nip roll side, which has a larger clamping force than the edge side nip roll,
It tends to be directed toward the small side. That is, the folded double-folded strip tends to be biased toward the edge. As a result, the double-fold superposed strip is always kept in good conformity with the folding plate on the double-fold side, and the linearity of the folding line is guaranteed. Therefore, it is possible to effectively suppress the occurrence of folding defects.

Further, when the folded double folded paper strip is conveyed while being sandwiched by the back side nip roll and the edge side nip roll, it bulges along the arc-shaped inner peripheral surface of each roll from the sandwiching surface through the paper escape expanding portion. It is possible to effectively prevent the linear indentation due to the strong pressure of the nip roll and the bulge.

[0007]

Embodiments of the present invention will be described below with reference to FIGS.

As described above, when the back side and the edge side of the folded double-folded paper 1 are sandwiched by the nip rolls 3 and 4 at the exit side of the folding plate 2 to impart folding, the double-folded overlapped strip 1 is laterally swung. There is a problem that the folding action of the folding plate 2 is impaired and a strong linear indentation is formed on the paper surface along the inner peripheral edge of the nip roll. Then, as a result of repeating various trials and studies to solve the above problems, the following was found as the cause of the above problems.

That is, with respect to the former problem, as shown in FIG. 5, the double-folded overlapped paper 1 is connected to each other via folding lines on the back side 1a (folding side), and on the edge side 1b. The leaves are separated and the back side 1a and the fore edge side 1b differ from each other in the pinching pressure by the nip rolls 3 and 4 and the feeding conditions. Due to this, the overlapping strip 1 sways in a direction orthogonal to the feeding direction, so-called meandering traveling,
The conformability with the folding plate 1 is impaired, the linearity of the folding line is impaired, and this causes the folding failure.

Regarding the latter problem, the nip roll 3,
In addition to applying a strong nip pressure to the strips 1 in the superposed state to give a fold, the double-folded polymer strip 1 swells up and down between the foreside nip roll and the back nip roll as shown in FIG. Of the nip rolls 3, 4 to form a linear indentation that clearly appears on the surface of the nip rolls 3, 4 in contact with the double-folded polymer web 1, particularly on the portion of the nip rolls that contacts the inner edge. It is a cause of spoiling the beauty.
The present invention has been made based on the above verification.

As described above, the folding plate 2 is provided as a means for folding the superposed strip 1 in which a plurality of strips are superposed on each other. The folded plate 2 has, for example, an isosceles triangular folded plate portion 2a,
The superposed strip 1'runs along the surface of the triangular folded plate portion 2a and forms a pair of oblique sides 2 forming the apex 2c of the triangular folded plate portion 2a.
By passing through b to apex 2c, the overlapped strip 1
A fold line is formed at the center of the strip at the vertex 2c while folding both sides of the sheet.

On the outlet side of the folding plate 2, nip rolls 3 and 4 for sandwiching the back side 1a and the fore edge side 1b of the polymerized strip 1 folded in two by the folding plate 2 are provided so as to face each other. Install in parallel. Two or more sets of the back side nip roll 3 and the front side nip roll 4 are arranged as shown in the drawing, or one set is arranged.

Thus, in the present invention, the holding pressure of the nip roll 3 for holding the back side of the above-mentioned double-folded polymer strip 1 is
The pressure is set to be larger than the clamping pressure of the nip roll 4 that clamps the edge side. As one of the means, each roll is elastically held by a spring 5, and the clamping pressure is set by adjusting the degree of compression of the spring 5 by a normal method.

Further, the inner peripheral surfaces of the back side nip roll 3 and the foreside side nip roll 4 are arcuate surfaces 3a, 4a for reducing the diameter toward the inside, and the inside facing parts of the backside nip roll 3 and the foreside side nip roll 4 are formed. Inwardly facing portions are defined the flared expanding portions 3b, 4b of the strip that gradually expand inward by facing the arc-shaped inner peripheral surfaces 3a, 4a, and the arc-shaped inner peripheral surface 3 is formed.
The outer end of a is used for sandwiching the folded folded strip 1. That is, at the outer end portion of the arc-shaped inner peripheral surface 3a, the inner end holding portions 3 of the back-side holding surface and the front-side holding surface of the double-folded overlapped strip are formed.
c, 4c are formed. The arcuate inner peripheral surfaces 3a and 4a are not limited to arcuate surfaces.

As a result, the folded double-folded paper strip 1 that has passed through the folding plate 2 has a tendency to be fed toward the small edge side by being promoted on the back side nip roll 3 side as compared with the small edge side nip roll 4 having a small clamping pressure. Due to this urging, the strip 1 is fed while being always in close contact with the surface and the top of the folding plate 2, and folding is performed in two. Further, the polymerized strip 1 folded in two by the folding plate 2 is swelled 1c between the rolls 3 and 4 as a phenomenon peculiar to the polymerized strip when it is nipped by the back side nip roll 3 and the edge side nip roll 4 and transferred. Both ends of the bulge 1c are formed between the back side nip roll 3 inside facing portion and the edge side nip roll 4 inside facing portion, and the paper escape expanding portion 3 is formed.
Bulging occurs along the escape arc-shaped inner peripheral surfaces 3a, 4a into b, 4b.

At this time, the folded double-folded paper strip 1 is sandwiched between the back side nip roll 3 and the fore edge side nip roll 4 in parallel by the sandwiching portions 3d and 4b.
While being clamped and fed at d, the arc-shaped inner peripheral surface 3
The sandwiching portions 3c and 4c at the inner end portions of a and 4a sandwich the inner end portions of the back-side sandwiching surface and the edge-side sandwiching surface of the folded folded strip 1 to assist the feeding.

[0017]

As described above, according to the present invention, the polymerized strip tends to be directed toward the fore edge side nip roll side by the pressing force of the back side nip roll, and the conformity of the polymerized strip to the folded plate is always ensured, and the polymerization is performed. The folding of the strip is performed properly and the linearity of the folding line is surely guaranteed. Therefore, the purpose of imparting a crease by the nip roll can be effectively achieved.

Further, when the polymerized strip is nipped by the back side nip roll and the edge side nip roll and transferred, it bulges along the arc-shaped inner peripheral surface forming the spreading portion while escaping into the spreading portion for paper escape. Therefore, it is possible to effectively prevent the generation of linear indentations on the surface of the strip due to the strong pressure of the nip roll and the bulge.

[Brief description of drawings]

FIG. 1 is a perspective view showing a folding device for a polymerized strip according to an embodiment of the present invention.

FIG. 2 is a plan view of the same.

FIG. 3 is a front view of the same.

FIG. 4 is an enlarged view of the front view.

FIG. 5 is a front view of a folded folded strip.

[Explanation of symbols]

 1 folded paper 1a back side 1b small edge side 1c bulge 2 folding plate 3 back side nip roll 4 small edge side nip roll 3a, 4a arc-shaped inner peripheral surface 3b, 4b paper escape flared portion 3c, 4c gripping portion 5 spring

Claims (1)

[Claims] 1. A nip roll for sandwiching the back side (folding side) and the small edge side of a double-folded polymeric strip and providing a crease on the exit side of the folded plate that guides the traveling of the polymeric strip. In the folding device of the polymerized strip provided, while setting the clamping pressure of the nip roll for clamping the back side to be larger than the clamping pressure of the nip roll for clamping the small edge side, the inner peripheral surfaces of the back side nip roll and the small edge side nip roll are set. An arc-shaped surface with a diameter that decreases inward, and the inner side of the dorsal nip roll and the inner side of the foreside nip roll gradually expand inward with the arc-shaped inner peripheral surface facing each other. A folding device for a polymerized strip characterized by defining an opening.