JPH0455003Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) This invention is a paper with a metal cap that is fitted and fixed to the end of a paper tube that serves as a core for winding newspaper rolls and other sheet materials. It is related to pipes.

(Prior art) The paper tube that serves as the core of a newspaper roll is set in a printing machine and the paper is pulled out with a strong pressing force applied to both ends of the paper tube. Metal caps are fitted and fixed at both ends of the paper tube to withstand the rotational force and braking force applied to the paper tube.

As shown in FIG. 8, the cap 2 consists of a cylindrical portion 21 that fits tightly into the inner surface of the paper tube 1, and a flange 22 that projects the outer end of the cylindrical portion 21 outward at a right angle and comes into contact with the end surface of the paper tube. , after fitting the cap 2 into the paper tube, the first
As shown in FIG. 0 and FIG. 11, the cap crimping device 70
It is fixed by caulking.

The caulking device 70 includes a plurality of sets of punch pieces 72 and press pieces 73, which are manufactured integrally or separately, arranged so as to be movable in the radial direction on a wedge shaft 71 having a conical tip. By pressing the
The punch piece 72 and the press piece 73 protrude in the radial direction, and the punch piece 72 is driven into the cylindrical part 21 of the base 2 to form a joint 3 that bites into the thickness of the paper tube. The inner end of the paper tube is bent so that it bites into the wall thickness of the paper tube.

The tip of the punch piece 72 is formed into a square pyramid with a side of approximately 10 mm, and the connecting portion 3 is recessed into a square pyramid shape corresponding to the shape of the tip of the punch piece, as shown in FIGS. The portion of the tip of the piece that corresponds to the ridgeline is cut in a cross shape, and four isosceles triangular claw pieces 31 bite into the thickness of the paper tube.

The above-mentioned paper tube with a cap had the following problems.

That is, as described above, when a paper roll is set in a printing press and the printing press is driven, both ends of the paper tube are pressed with a strong force and the paper is pulled out.

When the bonding force of the coupling portion 3 of the cap 2 was small, the cap 2 separated from the paper tube 1 and became free to rotate, sometimes idling on the inner surface of the paper tube. In this case, the paper is not fed smoothly, leading to troubles such as paper breakage or paper tangles inside the printing machine.

As shown in Figure 8, the four isosceles triangular claw pieces 3
Joint part 3 where 1 and 31 bite into the thickness of the paper tube
At first glance, the effect of preventing rotation on the paper tube seems to be great, but when we examine a case where the cap 2 slips against the paper tube during operation of the printing press, we find that the joint 3 has a slipping effect as shown in FIG. Among the claw pieces, the claw piece 31a that has bitten into the paper tube in the direction opposite to the rotation direction (arrow) is bent in the rotation direction, and the claw piece 31 facing the claw piece 31a is bent in the rotation direction.
b was downward along the inner surface of the paper tube.

This is because the cross-shaped cut 32 in the connecting part 3 causes the claw pieces 31a, 31b to bend in the direction of the applied force more easily than expected, thereby achieving the desired locking effect. I couldn't do that.

Therefore, the applicant previously proposed, as shown in Figure 7,
A paper tube with a cap was proposed in which the shape of the opening edge of the coupling part 3 was a recessed part 30 extending longer in the axial direction than the length in the circumferential direction (Utility Application No. 13677/1983).

In the above case, the concave portion 30 of the cap 2 is connected seamlessly from the opening edge to the side and bottom, and the paper tube near the joint 3 has a density due to the joint 3 biting into the wall thickness of the paper tube. is high and a dense portion 11 is formed.

Since there is no cut in the joint 3 as in the conventional case, that is, there is no weak part, the joint 3 can withstand a large deformation load.

Furthermore, since the connecting portion 3 extends long in the axial direction of the paper tube 1, it exhibits even greater resistance against slippage in the rotational direction.

Also, when forming the joint part 3, the paper tube 1 near the joint part
Since the dense portion 11 is formed in the paper tube and the density is high, the strength of the paper tube itself is increased, and it exhibits strong resistance against slipping of the joint portion 3, and the paper tube with the cap of the conventional example shown in FIG. In comparison, we were able to increase the effect of preventing rotation of the cap. However, even in the case of the paper tube with a cap shown in FIG. 7, the cap occasionally slips on the paper tube, and a more robust cap mounting technique is required.

(Means for solving the problem) The present invention presses the inner surface of the end of the paper tube with the entire cylindrical portion of the cap to reduce the density of the portion of the paper tube covered by the cap. This paper tube with a cap has a strong anti-rotation effect due to the wavy grooves formed in the cap.

In the paper tube with a cap of the present invention, the groove portions 23 extending over the entire length of the cylindrical portion 21 of the cap are arranged at equal intervals in the circumferential direction and are deformed into a wave shape and bite into the wall thickness of the paper tube.
The density of the paper tube in the part cut into by the groove increases to form the first dense part 11, and the thick part of the paper tube between the grooves 23 is equal to the thickness of the paper tube in the part where the cap 2 is not covered. A second dense portion 12 is formed whose density is higher than that of the second dense portion 12 .

(Operation and Effect) Since the entire cylindrical portion 21 of the cap 2 is deformed into a wave shape and presses the inner surface of the end of the paper tube, the contact area between the inner surface of the paper tube and the cap increases, and the The grooves 23 that are adjacent to each other in a wavy manner dig deeply into the wall thickness of the paper tube, forming the first dense portion 11 in the paper tube 1 and increasing the strength of the paper tube around the grooves. The stopping effect is further enhanced.

When the paper tube is rotated by pressing and holding the cap, pressure is applied to the thickness of the paper tube by the grooves 23 of the cap in a direction that opposes the rotation of the paper tube. The wall thickness is determined by the thickness of the paper tube in the circumferential direction due to the groove portion 23 of the cap because the second dense part 12 is formed and has a higher density than the wall thickness of the paper tube in the part where the cap 2 is not covered. It can fully withstand the pressing force of the paper tube, and exhibits even greater resistance to slipping in the rotational direction of the paper tube.

In addition, the cap does not have a cut as in the conventional case, that is, there is no weak part, so the cap itself can withstand a large deformation load.

(Example) The paper tube 1 has an inner diameter of about 80 mm and an outer diameter of about 112 mm.

The cap 2 is integrally provided with an outward flange 22 at one end of a metal tube, the wall thickness of the tube portion 21 is approximately 1 mm, and the outer diameter corresponds to the inner diameter of the paper tube 1.

FIG. 4 shows a device 7 for deforming the mouthpiece, in which a conical wedge shaft 71 is provided in the guide tube 4 so as to be retractable, and a reciprocating drive device (not shown) is attached to the shaft 71.
are connected.

Twelve guide holes 41 penetrating the inner and outer surfaces of the guide cylinder 4 are formed at equal intervals in the circumferential direction, and pressure blocks 5 are fitted into the guide holes so as to be slidable in the radial direction, and each block is fitted with a spring. 52, 52 is biased inwardly.

The guide hole 41 and the pressure block 5 are connected to the guide cylinder 4.
It is formed long in the axial direction.

The outer surface of the pressure block is formed into a mountain shape in both the width direction and the length direction of the block, and the top portion 51 of the pressure block is located near the tip of the guide cylinder 4.

The inner surface of the pressure block 5 is formed into a slope corresponding to the tapered surface of the wedge shaft 71, and when the wedge shaft 71 is protruded, the pressure block 5 moves in the radial direction and presses the peak portion 50 on the outer surface. It can be made to emerge from the guide hole 41.

Therefore, the cap 2 is tightly fitted to the end of the paper tube 1,
The cylindrical part 21 of the cap 2 is brought into close contact with the inner surface of the paper tube 1, and the flange 22 is brought into close contact with the end surface of the paper tube.

Next, as shown in Fig. 4, the outer periphery of the end of the paper tube is held in place by two rings 8, 8 which are opened and closed by a hydraulic cylinder (not shown), and then the mouthpiece deformation device 7, the peak portions 50 of each pressure block 5 are driven into the cylindrical portion 21 of the cap 2 all at once.

As a result, as shown in FIGS. 1 and 2, the cylindrical portion 21 of the cap 2 is deformed into a wavy shape in which grooves 23 extending in the axial direction are arranged at equal intervals in the circumferential direction, and the thickness of the paper tube increases. A paper tube with an indented cap is formed.

Each groove 23 becomes gradually deeper in the inner direction from the flange side opening of the cap 2 in correspondence with the peak 50 of the pressurizing block 5, and becomes gradually shallower toward the terminal end of the cap. The deepest part of the groove cuts into the paper tube 1 to a depth of about 6 mm.

The density of the paper tube in the portion into which the groove portion 23 bites is increased to form the first dense portion 11.

Further, as described above, the thick portion of the paper tube between the grooves 23 of the cap is pulled toward the grooves 23 when the cylindrical portion 21 of the cap is pressed and deformed by the pressing block 5. Therefore, it becomes a curved part that is roundly curved inward, and this curved part presses the paper tube from the inside, so the density between the grooves 23 and 23 of the paper tube is the same as the thickness of the paper tube in the part that is not covered with the mouthpiece. The density becomes higher than the thickness, and a second dense portion 12 is formed.

The present invention is not limited to the above configuration,
Various modifications are possible within the scope of the claims for utility model registration.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the paper tube with a cap of the present application, Fig. 2 is a sectional view taken along the line shown in Fig. 1, Fig. 3 is a longitudinal sectional view of the cap before deformation, and Fig. 4 is a cross section of the cap deforming device. Figure 5 is a front view of the guide cylinder housing the pressure block and wedge shaft, Figure 6 is a front view of the guide cylinder with the pressure block exposed, and Figure 7 is a proposal previously proposed by the applicant. FIG. 8 is a perspective view of a main part of a conventional paper tube with a cap, FIG. 9 is a sectional view of a main part of a conventional paper tube with a cap, FIG.
FIG. 1 is an explanatory diagram of the operation of a conventional crimping device. 1... Paper tube, 2... Cap, 21... Cylinder part, 3...
...joint part.

Claims (1)

[Scope of utility model registration request] In a paper tube with flanges fitted to both ends of the paper tube, the cylindrical portion 21 of the cap has a plurality of grooves 23 extending in the axial direction and cutting into the thickness of the paper tube, arranged in parallel in the circumferential direction, and adjacent grooves The area between 23 and 23 is deformed into a wave shape toward the thickness of the paper tube, and the density of the paper tube becomes higher at the part where the groove 23 bites into the thickness of the paper tube.
The thick part of the paper tube that forms the dense part 11 and corresponds to the wavy-deformed cylindrical part between the groove parts 23 has a second dense part 12 that is higher in density than the part of the paper tube that is not covered with the cap 2. A paper tube with a cap is formed.