JPS5820515Y2 - paper tube - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a paper tube having a bottom cover made of ABS resin and having a truncated conical convex portion formed in the center.

Conventionally, paper tubes have been widely used to protect packaged items such as paper products wrapped around paper tubes.

In these conventional paper tubes, the bottom cover is made of cardboard or paper tube base paper, and the bottom cover is bonded to the cylindrical body of the paper tube with a vinyl acetate resin.

However, in such paper cylinders, there is a risk that the bottom cover may peel off from the cylindrical body when a large amount of items to be packaged is inserted into the paper cylinder.

In addition, especially for paper cylinders with a large diameter, a metal one such as aluminum is used instead of a paper bottom cover.

Although such a paper cylinder having a metal bottom cover has a high pressure resistance, it has the disadvantage that the manufacturing process is difficult and the cost is high.

This invention eliminates these conventional drawbacks and provides a paper tube that is low cost, has high pressure resistance, and can prevent the movement of packaged items during handling or transportation. The lid has a truncated conical protrusion in the center and is made of ABS resin.

This invention will be explained below with reference to the drawings.

FIG. 1 is a sectional view showing an embodiment of this invention, and the paper tube has a cylindrical main body 1 and a bottom cover 2. As shown in FIG.

The cylindrical main body 1 is made of ordinary cardboard or paper tube base paper, and is formed to have an appropriate diameter depending on the size of the item to be packaged.

The bottom cover 2 is made of ABS resin, and has a truncated conical protrusion 3 at its center, which fits into the inner surface of the lower end of the cylindrical main body 1.

An adhesive such as vinyl acetate resin is applied to the side surface of the bottom cover 2 and the inner surface of the lower end of the cylindrical body 1 to fix them together.

Further, a buffer portion 4 made of a material such as polyurethane resin may be provided around the conical convex portion 3 of the bottom cover 2.

Furthermore, in the present invention, both the bottom cover 2 and the cylindrical body 1 can be made of ABS resin, and they can be integrally molded.

It will be understood from the above description that the bottom cover of this invention can also be applied to the top cover.

As mentioned above, since the bottom cover of the paper tube of this invention is made of ABS resin having a truncated conical protrusion in the center, the bond between the bottom cover and the cylindrical body is made of ordinary vinyl acetate resin. It is strongly bonded with an adhesive such as, improving its pressure resistance, simplifying the manufacturing process, and the truncated cone-shaped protrusion provided in the center of the bottom cover results in a recess on the inner circumferential surface of the bottom of the paper tube. As a result, the item to be packaged, such as a roll, is smoothly inserted into this recess along the inner circumferential surface of the paper cylinder, making it easier to insert the item to be packaged, and the inserted item to be packaged. The truncated conical protrusion provided at the center of the bottom cover prevents the paper from moving inside the paper tube during handling or transportation, thus preventing the packaged items from scratching or tearing as they move. .

Examples are shown below.

Embodiment According to this invention, a paper tube with a bottom cover made of ABS resin as shown in FIG. Compared to the cylinder.

For those whose bottom lids were made of paper or ABS resin, vinyl acetate resin was used as an adhesive, and for those made of metal, they were fitted and no adhesive was used.

The pressure resistance was determined by inserting a 5 kg paper product into a paper cylinder as an object to be packaged, and examining whether the bottom cover would easily peel off when the paper product was dropped from a height of 1.5 m.

Ease of manufacture was determined by considering the ease of fitting the bottom cover into the paper cylinder and the ease of adhering it.

The results are shown in the table below.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing one embodiment of this invention. 1...Cylindrical body, 2...Bottom cover, 3.
...Frustrated cone-shaped convex part, 4...Buffer part.

Claims (1)

[Scope of utility model registration request] A paper cylinder characterized in that a bottom cover 2 that is fitted and adhered to the inner surface of the lower end of a cylindrical main body 1 has a truncated conical protrusion 3 in the center and is made of ABS resin.