JP7621888B2 - Method for winding synthetic resin sheets - Google Patents

Description

The present invention relates to a method for winding a synthetic resin sheet.

At construction sites and other locations, various perforated and non-perforated synthetic resin sheets are used, such as sheets used as vibration damping materials to reduce vibrations caused by heavy machinery when it travels, sheets to reinforce slopes and paved roads, netting to prevent animal damage, sheets to protect lawns, and sheets to suppress the overgrowth of weeds. The sheets used for these purposes are usually in strips several tens of meters long, so they are transported and stored rolled up into a cylindrical shape.

However, a sheet that has been rolled up into a cylindrical shape will develop a tendency to curl, which creates the problem that when the rolled up sheet is unrolled, the sheet will partially unroll. To maintain the sheet in its unrolled state, weights are placed on the longitudinal ends of the unrolled sheet to prevent the sheet from unrolling. In some cases, the unrolled portion may be rerolled in the opposite direction to prevent the sheet from unrolling, or the unrolled sheet may be turned over. However, taking such measures to prevent unrolling is cumbersome.

The following Patent Document 1 discloses a method for correcting curling by applying heat to a synthetic resin sheet to soften the sheet, but no document has been found that discloses a winding method that can prevent the sheet from unwinding.

Japanese Patent Application Publication No. 4-179531

In view of the above, the objective of the present invention is to provide a method for winding a synthetic resin sheet that can suppress the rewinding of the synthetic resin sheet.

According to the present invention, there is provided the following synthetic resin sheet winding method that solves the above-mentioned problems. That is, there is provided a synthetic resin sheet winding method, which includes the steps of setting a winding centerline extending in the width direction of the synthetic resin sheet at a position away from one longitudinal end of the synthetic resin sheet by a predetermined length toward the other longitudinal end, and winding the sheet around the winding centerline, in which the step of setting the winding centerline sets the position of the winding centerline so that when the wound-up sheet is unfolded, unwinding of the sheet caused by a curling tendency is hindered by gravity acting on a portion of the entire sheet from one longitudinal end to the winding centerline (excluding the case where one longitudinal end of the sheet is moved toward the other longitudinal end to bring end regions in the longitudinal direction of the sheet into contact with each other, thereby generating flat end regions from the longitudinal end regions of the sheet and generating a curved central region from the central region of the sheet, and winding up the curved central region toward the flat end region) .

Preferably, in the step of winding up the sheet, the winding center line is clamped from both one side and the other side of the sheet by a pair of chucks extending in the width direction of the sheet, and then the sheet is wound up by rotating the pair of chucks. It is preferable that the method includes a step of setting a fold-back line extending in the width direction of the sheet at a position a predetermined distance away from the other longitudinal end of the sheet toward the one longitudinal end, and a step of folding back the wound up sheet along the fold-back line.

In the present invention, the position of the winding center line is set so that the gravity acting on the portion of the entire sheet from one longitudinal end to the winding center line prevents the sheet from unwinding due to the curling tendency when the rolled up sheet is unfolded, so that the unwinding of the sheet when the rolled up sheet is unfolded can be suppressed. Therefore, according to the present invention, it is not necessary to take measures to suppress unwinding, such as placing a weight on the end of the sheet when the rolled up sheet is unfolded, rewinding the curled portion in the opposite direction, or turning the unfolded sheet over, and the rolled up sheet can be easily laid down.

1 is a perspective view of a synthetic resin sheet in which the present invention can be implemented; 2 is a perspective view showing a state in which the winding center line of the sheet shown in FIG. 1 is positioned between a pair of chucks; FIG. 3 is a perspective view showing a state in which the center line of the sheet is clamped by the pair of chucks shown in FIG. 2 . 4 is a perspective view showing a state in which the pair of chucks are rotated from the state shown in FIG. 3 to start winding up the sheet; FIG. FIG. 4 is a schematic diagram of a wound sheet viewed in the width direction. FIG. 4 is a schematic diagram of the rolled sheet with a portion of the sheet folded back.

Below, a preferred embodiment of the synthetic resin sheet winding method of the present invention will be described with reference to the drawings.

The synthetic resin sheet 2 shown in FIG. 1 (hereinafter simply referred to as "sheet 2") is a net-like sheet having a rectangular shape overall and many holes, but may be a sheet without holes. The material of sheet 2 may be either a thermoplastic resin (e.g., olefin resin, silicone resin, etc.) or a thermosetting resin (e.g., urethane resin, imide resin, etc.).

In the illustrated embodiment, first, a step is carried out in which a winding centerline 4 extending in the width direction of the sheet 2 is set at a position a predetermined length away from one longitudinal end 6 of the sheet 2 toward the other longitudinal end 8. In the step of setting the winding centerline 4, the position of the winding centerline 4 is set so that when the wound sheet 2 is unfolded, gravity acting on the portion of the entire sheet 2 from one longitudinal end 6 to the winding centerline 4 prevents the sheet 2 from unwinding due to its curling tendency.

When the sheet 2 is rolled up into a cylindrical shape, a relatively strong curl is formed in the innermost part of the rolled up sheet 2 (the part where the rolling starts). Then, when the rolled up sheet 2 is unrolled, the sheet 2 unrolls starting from the part where the rolling starts, where the curl is relatively strong.

Therefore, by setting the winding center line 4 at a position a predetermined length away from one longitudinal end 6 of the sheet 2 toward the other longitudinal end 8, the winding center line 4, which is the starting point for rewinding the sheet 2, is separated from the one longitudinal end 6, and the portion of the entire sheet 2 from the one longitudinal end 6 to the winding center line 4 can be given the function of a "weight" to suppress rewinding of the sheet 2. As a result, when the rolled up sheet 2 is unfolded, the unwinding of the sheet 2 can be suppressed without placing a weight on the end of the sheet 2, and the unfolded state of the sheet 2 can be maintained.

As can be understood by referring to FIG. 1, the longitudinal end 6 of the sheet 2 is the end closer to the winding center line 4, and conversely, the longitudinal end 8 of the sheet 2 is the end farther from the winding center line 4.

After the winding center line 4 is set, a step of winding the sheet 2 around the winding center line 4 is carried out. The step of winding the sheet 2 can be carried out, for example, using a winding device 10 shown in FIG. 2. The winding device 10 includes a pair of rod-shaped chucks 12 and an operating means (not shown) for operating the pair of chucks 12. The chucks 12 have a one-side chuck 12a and an other-side chuck 12b that can move toward and away from each other in the longitudinal direction of the chucks 12.

In the step of winding up the sheet 2, first, the longitudinal direction of the sheet 2 is aligned in the direction indicated by the arrow X in Fig. 2. Next, the sheet 2 is fed in the X direction, and the winding center line 4 is positioned between a pair of chucks 12 spaced apart from each other. Next, as shown in Fig. 3, the pair of chucks 12 extending in the width direction of the sheet 2 (the direction indicated by the arrow Y in Fig. 3) are brought close to each other, and the pair of chucks 12 clamp the winding center line 4 from both one side and the other side of the sheet 2.

After the sheet 2 is clamped between the pair of chucks 12, as shown in FIG. 4, the pair of chucks 12 are rotated in the direction indicated by the arrow R in FIG. 4. This allows the sheet 2 to be easily wound up by the pair of chucks 12. Note that when winding up the sheet 2, the pair of chucks 12 may be rotated in the direction opposite to the direction R.

Figure 5 shows the state in which the sheet 2 is wound around a pair of chucks 12. In Figure 5, a gap is provided in the sheet 2 in the radial direction in order to clearly show the position of one longitudinal end 6 of the sheet 2. Once the sheet 2 is wound up, the one-side chuck 12a and the other-side chuck 12b are moved away from each other, and the chuck 12 is pulled out from the cylindrically wound sheet 2.

Furthermore, as shown in FIG. 6, it is desirable to perform a step of setting a fold line extending in the width direction of the sheet 2 at a position 14 a predetermined length away from the other longitudinal end 8 of the sheet 2 toward the one longitudinal end 6, and a step of folding the rolled up sheet 2 along the fold line.

The other longitudinal end 8 is the outermost part of the cylindrically wound sheet 2, so the curling tendency at the other longitudinal end 8 is relatively weak. However, unwinding may occur at the other longitudinal end 8. Therefore, by setting a fold line at a position 14 a predetermined distance away from the other longitudinal end 8 of the sheet 2 toward the longitudinal one-side end 6 and folding the wound sheet 2 along the fold line, it is possible to prevent the sheet 2 from unwinding from the other longitudinal end 8 of the sheet 2.

The position 14 for setting the fold-back line may be set so that, when the rolled up sheet 2 is unfolded, the rewinding of the sheet 2 from the other longitudinal end 8 is hindered by gravity acting on the portion of the entire sheet 2 from the other longitudinal end 8 to the fold-back line.

As described above, in the illustrated embodiment, in the step of setting the winding center line 4, the position of the winding center line 4 is set so that when the rolled up sheet 2 is unfolded, the rewinding of the sheet 2 caused by the curling tendency is inhibited by gravity acting on the portion of the entire sheet 2 from one longitudinal end 6 to the winding center line 4. This makes it possible to suppress the rewinding of the sheet 2 when the rolled up sheet 2 is unfolded and maintain the unfolded state of the sheet 2.

Therefore, according to the illustrated embodiment, when the rolled up sheet 2 is unfolded, there is no need to take measures to prevent the sheet 2 from unwinding, such as placing a weight on the end of the sheet 2, rewinding any curled parts in the opposite direction, or turning the unfolded sheet 2 over, and the rolled up sheet 2 can be easily laid down.

The synthetic resin sheet winding method of the illustrated embodiment can be applied to a variety of perforated or non-perforated synthetic resin sheets, such as sheets used as vibration damping materials to reduce vibrations caused when heavy machinery runs on construction sites, sheets to reinforce slopes and paved roads, nets to prevent animal damage, sheets to protect lawns, and sheets to suppress the overgrowth of weeds. The synthetic resin sheet winding method of the illustrated embodiment can be applied not only when the sheets are manufactured, but also when putting away the sheets after use.

Here, the inventor will explain the experiment that he conducted. Using the following synthetic resin sheet, the inventor rolled up several sheets with different lengths from one end of the longitudinal direction to the winding center line into a cylindrical shape around the winding center line as the axis, and stored the several sheets in the cylindrically rolled state for four weeks to give each sheet a curling tendency, after which he unrolled each sheet to check for the presence or absence of unrolling.

<Seat material, etc.>
Material: Olefin-based thermoplastic elastomer Shape: Perforated rectangular sheet (strip net)
Dimensions: Length 10m, width 1m, thickness 10mm
Density: 880 kg/ ^m3 (density of the material itself excluding pores)
Weight per unit area: 2.2 kg/ ^m2 (weight per unit area including holes)
Durometer hardness: 90 (Type A)

<Experimental Results>
Length from one end of the length to the winding center line Presence or absence of rewinding
0m Yes (×)
0.6m Yes (x)
1.0m Yes (x)
2.0m None (○)

Conclusion
By setting the winding centerline extending in the width direction of the sheet at a position 2 m away from one longitudinal end of the sheet toward the other longitudinal end, it was possible to prevent the sheet from rewinding and maintain the sheet in its unfolded state.

In addition, in the synthetic resin sheet used in the above experiment, a fold line was set 1 m away from the other longitudinal end of the sheet toward one longitudinal end, and the rolled up sheet was folded back along the fold line, making it possible to prevent the sheet from unwinding from the other longitudinal end.

2: Synthetic resin sheet 4: Winding center line 6: One end in the longitudinal direction 8: The other end in the longitudinal direction 10: Winding device 12: Chuck 12a: One-side chuck 12b: The other-side chuck 14: Position at a predetermined distance from the other end in the longitudinal direction of the sheet

Claims (3)

A method for winding a synthetic resin sheet, comprising the steps of:
A step of setting a winding center line extending in a width direction of the synthetic resin sheet at a position a predetermined distance away from one longitudinal end of the sheet toward the other longitudinal end of the sheet;
and winding the sheet around the winding center line,
In the step of setting the winding center line, the position of the winding center line is set so that gravity acting on the portion of the entire sheet from one longitudinal end to the winding center line prevents the sheet from unwinding due to a curling tendency when the wound up sheet is unfolded (however, this does not include the case where one longitudinal end of the sheet is moved toward the other longitudinal end to bring the longitudinal end regions of the sheet into contact with each other, thereby generating flat end regions from the longitudinal end regions of the sheet and generating a curved central region from the central region of the sheet, and rolling up the curved central region toward the flat end region). The synthetic resin sheet winding method according to claim 1, wherein in the step of winding the sheet, the winding centerline of the sheet is clamped from both one side and the other side of the sheet by a pair of chucks extending in the width direction of the sheet, and then the sheet is wound by rotating the pair of chucks. setting a fold-back line extending in a width direction of the sheet at a position a predetermined length away from the other longitudinal end portion of the sheet toward one longitudinal end portion of the sheet;
The synthetic resin sheet winding method according to claim 1 or 2, further comprising a step of folding back the wound sheet along the folding line.

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