JP2000055257A - Joint method for paper tube - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enlarge the mechanical strength by grinding the end outer circumferential face of an extending-side paper tube into a recessed/projecting state, by grinding the end internal circumferential face of the joint side paper tube into a recessed/projecting fitting shape, and by fittingly joining the recesses/ projections with each other. SOLUTION: One end outer circumferential face of a short industrial paper tube 1 is ground by a lathe so as to form ground parts of four projections and four recesses on a diagonal line. The grinding conditions are set to, for example, a projection grinding quantity 5 mm (wall thickness 10 mm), a recess grinding quantity 10 mm (wall thickness 5 mm), and the grinding length 30 mm. One end internal circumferential face of the other short industrial paper tube 3 is ground to form ground parts fitted to the ground parts of the paper tube 1. The paper tube 1 and the paper tube 3 are joined together by fitting the mutual ground parts so as to provide a paper tube 5 of a necessary length. The paper tube 5 can be used for, for example, winding the paper without buckling and twist and provide smooth operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method of joining paper tubes having a short length to obtain a paper tube of a required length. The present invention relates to a method of joining a paper tube in which the outer peripheral surface of the paper tube and the inner peripheral surface of another paper tube are ground so as to have irregularities, and both are fitted.

[0002]

2. Description of the Related Art Conventionally, paper tubes used in factories and the like are usually used repeatedly. After several uses, the paper tube becomes unusable due to deformation, damage, dirt, etc.Therefore, this paper tube should be incinerated or returned to recycled materials.
A method of reusing only a good paper tube portion by joining it to a required length is often used.

[0003] As a method of removing a bad portion of a paper tube and bonding only a good portion of the paper tube to a required length for reuse, the paper tube is cut at a right angle to the longitudinal direction. Butt the paper tubes from each other and join the cut surfaces with adhesive,
Alternatively, staples are driven in with a pistol-type stapler to join and fix. Also recently,
In order to improve strength such as buckling and twisting, a method has been proposed in which an iron core is inserted into an inner hollow portion where the cut ends of a paper tube abut each other, and joined and fixed with a stapler.

[0004]

As described above, paper tubes used in the past, especially in industrial use, are repeatedly used, but become unusable due to deformation, damage, dirt and the like after several uses. Therefore, the bad portion of the paper tube is removed, and the good portion is cut out and joined to a required length to be recycled and reused. As a method of recycling the old paper tube, as described above, there is a method in which the paper tube is cut at a right angle to the longitudinal direction, and the cut surfaces are joined to each other and bonded with an adhesive. Since the surface area is small and the adhesive strength of the adhesive is not sufficient, the adhesive may be damaged by buckling or torsion during use, and furthermore, there is a drawback that labor and time are required for bonding.

[0005] As a method of recycling an old paper tube, the paper tube is cut at right angles to the longitudinal direction of the paper tube in the same manner as described above.
The method of joining and fixing staples with a pistol-type stapler by abutting the cut surfaces is not strong enough, so it may occasionally be damaged during use, and this recycling method also applies staples to the paper core surface. There is a problem that the stamp is attached to the core portion of the paper due to the stepped portion due to the addition, resulting in a defect.

[0006] In addition, this recycling method uses metal staples, which hinders its final use as a papermaking raw material. Furthermore, a method of joining and fixing with a stapler that inserts an iron core into the inside hollow part where the cut ends of the paper tube that are proposed to improve the strength such as buckling and torsion are joined is quite powerful. However, the problem of the loss of the core part of the paper and the final disposal of the paper tube caused by the use of the stapler, that is, the problem when using it as a recycled material (the danger of contaminating foreign matter) is described above. Exists in the same manner as the reproduction method.

[0007]

Means for Solving the Problems The present invention has been achieved as a result of intensive studies to solve the above problems.
In other words, the present invention is a method of joining a plurality of paper tubes in a length direction to extend the required length of the paper tubes, and the outer end surface of the paper tube before extension is formed with irregularities on the outer peripheral surface. The other end of the paper tube that is ground and joined to the inner periphery of the paper tube has a shape that can be fitted with the unevenness of the paper tube in order to prevent the individual paper tubes from rotating independently and freely. A method of joining paper tubes, characterized in that the surfaces are ground and joined so that the irregularities of both are fitted to each other to obtain a required length.

In the present invention, the surface of the fitting portion (insertion portion) of the paper tube is provided with irregularities in order to prevent the paper tubes from rotating with respect to each other. From the viewpoint of ease of manufacture and effect, it is preferable to form groove-like or ridge-like irregularities along the length of the paper tube. In the case of an industrially used paper tube (outer diameter 109 mm, inner diameter 79 mm, wall thickness 15 mm), the grinding thickness is 5 mm (shallow part) to 10 mm (deep part).
The grinding length (insertion length of the paper tube) is preferably about 20 to 50 mm. Furthermore, in the present invention, it may be better to apply an adhesive to the ground surface and fix it.

[0009]

FIG. 1 shows an industrial paper tube (outside diameter 109 mm, inside diameter 79 mm, wall thickness 15 mm) before being extended to a required length by grinding the outer peripheral surface of an end portion to form a convex portion and a concave portion on a diagonal line. It is a perspective view provided in four places. FIG. 2 is a perspective view in which an inner peripheral surface of an end portion of another same type of paper tube joined to the paper tube of FIG. 1 is ground so as to be fitted with the paper tube of FIG. FIG. 3 is a perspective view of the paper tube of FIGS. 1 and 2 fitted and joined to a required length.

First, the outer peripheral surface of one end of the short industrial paper tube (1) was ground by a lathe to form four convex portions and four concave portions (2) diagonally. At this time, the grinding amount of the convex portion is 5 m.
m (wall thickness: 10 mm), the amount of grinding of the concave portion was 10 mm (wall thickness: 5 mm), and the grinding length was 30 mm. Another short industrial paper tube (3) (same type as above) is ground (4) at one end so that the ground paper tube can be fitted, and then both are fitted. Then, a paper tube (5) having a required length was obtained. The paper tube was provided with caps at both ends, set on a winding machine, and the paper was wound up. As a result, the work was performed smoothly without buckling or twisting of the paper tube. In addition, there was almost no loss of paper in the core portion, and the result was good.

[0011]

As described above, according to the present invention, the outer peripheral surface of the end portion of the paper tube before being extended to the required length is ground so as to form irregularities, and the other end of the paper tube to be joined therewith. The part is obtained by grinding the inner peripheral surface into a shape that can be fitted to the above-described paper tube, and fitting both to obtain a paper tube of a required length. The paper tube recycled by this method has the advantage of being able to be recycled at a low cost because the operation is almost mechanized in addition to having high mechanical strength.

[Brief description of the drawings]

FIG. 1 is a perspective view of an outer peripheral surface of an end portion of a paper tube before being extended to a required length, which is provided with four concave and convex portions on a diagonal line.

FIG. 2 is a perspective view of an inner peripheral surface of an end portion of another paper tube joined to the paper tube of FIG. 1 ground to a shape that can be fitted to the paper tube.

3 is a perspective view of the paper tube of FIG. 1 fitted to and joined to the paper tube of FIG. 2 to a required length.

[Brief description of reference numerals]

DESCRIPTION OF SYMBOLS 1 Paper core of short length before extending to required length 2 Grinding part of the outer peripheral surface of paper core of 31 3 Other paper core to be joined 4 1 Grinding part of inner peripheral surface of paper core of 3 5 2 A paper tube with two paper tubes fitted and joined to the required length

Claims (2)

[Claims] 1. A method for joining a plurality of paper tubes in a longitudinal direction to extend the tube to a required length, wherein an outer peripheral surface of an end portion of the paper tube before extension is formed with irregularities. The other end of the paper tube that is ground and joined to the inside of the paper tube has a shape that can be fitted with the unevenness of the paper tube in order to prevent the individual paper tubes from rotating independently and freely. A method for joining paper tubes, wherein a peripheral surface is ground and joined so that the two projections and depressions are fitted to each other to have a required length. 2. The paper tube according to claim 1, wherein groove-shaped or ridge-shaped irregularities are formed in the longitudinal direction on the outer peripheral surface or inner peripheral surface of the end portion of the paper tube by grinding, fitted and joined. Joining method.