JP2898884B2 - Plastic sheet with folded creases, method of manufacturing the same, folded crease blade and plastic case - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a plastic sheet with a folded crease, a method for producing the same, and a folded crease blade.

[0002]

2. Description of the Related Art A plastic sheet with a folding ruled line, which is used as a material of an assembly case made of plastic, is provided with a groove-shaped folding ruled line at a bent portion of a flat plastic sheet so as to be easily bent from this portion. As shown in a perspective view in FIG. 11, the conventional folding ruled line 2 is formed as one groove portion 261, two groove portions 262, 263 or a groove portion having a deep groove portion 264, a shallow groove portion 265 and a two-stage depth in the longitudinal direction. There is a method of using a structure in which stress at the time of bending is reduced, a method of using a heated ruled blade, or a method of forming a bent ruled line by pressing a bent portion of a plastic sheet while heating with high frequency.

[0003]

However, the former one,
In any groove having two or two steps, the entire sheet is strongly pressed by a ruled blade having a cutting edge shape corresponding to the shape of the groove to thin the groove, so that the molecules in the plastic at the ruled line are strong. It is compressed by pressing, and the physical strength of the part is reduced, so that there is a drawback that it is not possible to make a ruled line so deeply or that it is softly bent when it is deeply inserted.

Further, when a large number of bending ruled lines and contours are punched out at the same time in order to press and process the entirety at a high pressure, a large pressing force is required and the plastic sheet between the bending ruled lines is warped. In particular, there is a drawback that, in the case of bending and pasting in a subsequent step, it is not possible to send one by one well and automation cannot be achieved.

In the latter method using a heated ruled line blade or a method using high frequency, it is difficult to process at high speed, and it is not possible to heat evenly from the viewpoint of thermal management, and the ruled line depth of the entire case is reduced. It is difficult to make it uniform, and depending on the sheet material, physical properties may be deteriorated by heating.

[0006]

SUMMARY OF THE INVENTION The present invention has a completely new structure devised to solve the above problems,
In the folding crease-containing plastic sheet, the folding crease has a cutting edge having an uneven shape in a length direction.
Press the bent ruled line blade against the sheet and cut into the convex part of the blade edge
And the deep groove formed while spreading
The stretched portion formed by stretching in the width direction by spreading
A plastic sheet with a folding ruled line, which is provided alternately in the length direction . This fold
The extension of the crease line is the bottom of the concave part
Make sure that the sheet does not touch the sheet
Stretched in the width direction by pushing and spreading the convex part of the cutting edge
Can be provided. The plastic with the folding ruled line of the present invention
According to the stick sheet, especially with the effect of the stretched portion, even if the entire average thickness of the ruled line portion is reduced, it is possible to obtain a ruled line having good bendability without breakage or breakage from the ruled line portion.

[0007] The length of the deep groove portion is set at 0. 3
Is to 3.0 times, the depth of the deep groove portion 0 of the sheet thickness. 5
1.0 to 1.0 times, and the opening width of the deep groove is 0.1 mm of the sheet thickness.
The length of the stretched portion is 0.3 to 3.0 times the sheet thickness.
Since it is 3 to 3.0 times and the thickness of the stretched portion is smaller than the thickness of the sheet, a plastic sheet with a folded crease can be obtained in which the ease of folding and the difficulty of breakage or breakage are well balanced.

In addition, since the stretched portion has a saddle-shaped upper surface, when the plastic sheet is bent from the folding ruled line, each stretched portion is bent in a state where the corners are rounded, so that there is no risk of being caught by the fiber of the clothing. .

[0009] Then, a folded ruled blade having an uneven edge in the longitudinal direction is pressed against a plastic sheet to bite the convex portion of the edge and expand the edge, thereby forming a deep groove portion, and touching the bottom surface of the concave portion of the edge with the sheet. To make
By extending the plastic sheet portion between the convex portions in the width direction by the above-mentioned spreading, forming a stretched portion between the deep groove portions, a method for producing a folded crease-lined plastic sheet, characterized in that, A folding ruled line having an extension can be formed very easily.

Further, the cutting edge has an uneven shape in the length direction, and the length of the protruding portion of the cutting edge is 0.3 to 3.0 of the sheet thickness.
Double, the length of the concave portion of the blade edge is 0.3 to 3.0 of the sheet thickness.
And the bite height of the convex part of the blade is 0.5 times or more of the sheet thickness and the bottom of the concave part of the blade does not touch the sheet.
Make sure that the absolute height is greater than the bite height.
The maximum width of the cutting edge protrusion is 0.3% of the sheet thickness
Folded ruled blades of up to 3.0 times are suitable for producing excellent folded ruled plastic sheets.

[0011] The plastic with the folding ruled line of the above construction
The seat is the material of the plastic assembly case.
Plastic sheet with a predetermined amount with glue allowance and flap
Punched into a blank sheet with the contour of
Bend and glue both ends with glue allowance.
If the wrap is folded and closed, it becomes a case. The details will be described below with reference to the drawings.

FIG. 1 is a perspective view showing an example of a plastic sheet with a folded crease according to the present invention, FIG. 2 is a sectional view taken along line II-II of FIG. 1, FIG. 3 is a sectional view taken along line III-III of FIG. FIG. 4 is a front sectional view illustrating a method for manufacturing a plastic sheet with a folding ruled line according to the present invention, and FIG.
6 to 9 are side sectional views showing another example of the folding ruled line blade of the present invention, and FIG. 10 is a perspective view showing an example of a cylindrical body made of the plastic sheet with the folding ruled line of the present invention. FIG. 11 is a perspective view showing an example of a conventional plastic sheet with a folding ruled line.

As shown in FIGS. 1 to 3, a plastic sheet with a folding ruled line according to the present invention comprises a plastic sheet 1 with a folding ruled line, wherein the folding ruled line 2 has a large number of deep grooves 3 and extended portions 4 in the longitudinal direction. It is a plastic sheet with folded ruled lines, which is provided alternately.

In the present invention, the plastic sheet 1 has a thickness of about 0.1 to 3.0 mm, and is made of a single material such as polyvinyl chloride, polyethylene terephthalate, polypropylene, polystyrene, polycarbonate, polyethylene, or a composite material with paper. A semi-rigid or rigid sheet made of a composite material of a plastic and another plastic can be used. Furthermore, a nonwoven fabric or the like can also be processed, that is, it is sufficient that it can be stretched.

The deep groove portions 3 and the extending portions 4 forming the folding ruled lines 2 are formed alternately, and the deep groove portions 3 have an action of softening the folding ruled lines 2, and the longer the length L3, the easier the bending. The extending portion 4 is sandwiched between the front and rear by the deep groove portion 3 and has an action of maintaining the strength of the folded ruled line 2.

As shown in FIGS. 2 and 3, the length L3 of the deep groove portion 3 is equal to the thickness T of the sheet. The depth D3 of the deep groove 3 is 0.3 to 3.0 times the sheet thickness T. 5 to 1.0 times, and the opening width W3 of the deep groove portion 3 is 0. 0 of the sheet thickness T. 3 ~
3.0 times, and the length L4 of the stretched portion 4 is 0.3 times the sheet thickness T. Since the thickness T4 of the stretched portion 4 is smaller than the sheet thickness T, the balance between the ease of bending and the difficulty of breaking or breaking is further improved.

Further, as shown in FIGS. 1 and 2, the extending portion 4 has a saddle-shaped upper surface portion 41, so that the plastic sheet 1 is folded from the folding ruled line 2 so that the upper surface portion 41 is bent outward. At the time of bending, each extending portion 4 bends in a state where the front and rear corners 42 of the upper surface portion 41 are rounded, so that there is no possibility of being caught by fibers of clothing,
Since the bending position is stabilized in the narrow range of the center thinnest portion 43 of the saddle shape, there is an effect that the bending line is inconspicuous.

As shown in FIGS. 4 and 5, in order to process the plastic sheet with the folding ruled line according to the present invention, the cutting edge of the folded ruled line blade 5 having a concave-convex shape in the length direction is pressed against the plastic sheet 1. The deep groove portion 3 is formed while the convex portion 53 is pierced and spread, and the plastic sheet portion 14 between the convex portions 53 of the cutting edge is stretched in the width direction by the spread, and the extended portion is formed between the deep groove portions 3. By the method of manufacturing a plastic sheet with a folded crease, which is characterized by forming the crease 4, the creased crease 2 having the deep groove portion 3 and the extended portion 4 can be formed very easily.

A cradle 6 made of an iron plate or the like is installed under the plastic sheet 1, and a folding ruled line blade 5 whose cutting edge has an uneven shape in the length direction is pressed from above the plastic sheet 1, thereby forming a folding ruled line. 2 is obtained.

When the maximum width W53 of the projection 53 of the cutting edge and the height H53 of the biting of the projection 53 of the cutting edge are increased, the opening width W3 of the upper surface of the deep groove 3 is increased, and the extending portion 4 is greatly elongated. 2, its thickness T4 becomes smaller.

If the maximum width W53 of the protrusion 53 of the cutting edge is too small and the extension 4 is not stretched and its thickness T4 is not reduced, it is difficult to bend. On the other hand, if it is too large, excessive pressure may be applied to the sheet during the pressing process, and the ruled line portion may be hardened, or the stretching ratio of the stretching portion 4 may be too high, and cracks may occur in the upper surface portion 41.

The shape of the upper surface portion 41 of the elongated portion 4 can be saddle-shaped. This is the convex part 5 of the cutting edge.
The plastic sheet portion 14 between the protruding portions 53 of the cutting edge is not only stretched in the width direction due to the push-out due to the biting of 3, but also the meat is dragged in the front-rear direction by the protruding tip near the center. In general, when the plastic is stretched, the thickness of the plastic becomes thinner and it becomes easier to bend, and the tensile strength is improved by the stretching, so that the folding ruled line 2 is hardly broken.

Further, the ruled-line blade 5 can form the folded ruled line 2 only by the protrusion 53 of the blade edge pressing the deep groove portion 3 without touching the extended portion 4. Since it is pressed only in a specific manner, it can be processed with a small pressing force, and the plastic sheet 1 between the folding ruled lines 2 does not warp due to the pressing stress.

In the thick portion of the plastic sheet 1, the convex portion 53 of the cutting edge is deep, and the pushing and spreading effect is large, and the thickness of the stretched portion 4 tends to be small, so that the plastic sheet 1 tends to be bent. Even if uneven, the bending of the ruled line is relatively stable.

The cutting edge has an uneven shape in the length direction, and the length L53 of the convex portion 53 of the cutting edge is 0.3 to 3.3 of the sheet thickness T.
0 times, the length L54 of the concave portion 54 of the cutting edge is 0.3 to 3.0 times the sheet thickness T, and the biting height H53 of the convex portion 53 of the cutting edge is 0.5 times or more the sheet thickness T. In addition, the absolute height H530 is larger than the bite height H53, and the maximum bite width W53 of the protrusion 53 of the cutting edge is 0.
The folding ruled line blade 5 having a magnification of 3 to 3.0 times is suitable for producing an excellent folded ruled plastic sheet.

If the biting height H53 of the convex portion 53 of the blade edge is 0.5 times or more the sheet thickness T, it is easy to bend and the extended portion 4 can be formed by pushing and expanding. Further, since the absolute height H530 of the projection 53 of the cutting edge is greater than the height H53 of the cutting edge, even when the cutting portion is pressed up to the height H53, the bottom portion 541 of the concave portion 54 of the cutting edge is simply pushed and spread to extend the extending portion 4. Can be formed, so that the pressing force by the cutting edge can be prevented from being applied to the extending portion 4. In this case, it is also possible to increase the bite height H53 so that the convex portion 53 of the blade bites into the entire sheet thickness T to open the hole. On the other hand, when sealing is required, as shown in FIGS. There is also a method of leaving the remaining meat portion 13 at the bottom.

If the length L54 of the concave portion 54 of the cutting edge is set to be larger than 3.0 times the sheet thickness T, the effect of expanding by the convex portion 53 of the cutting edge cannot be exhibited to the inside of the center of the extending portion.
There is a portion that is not stretched and is not thinner than the sheet thickness T. On the other hand, if it is 0.3 times or less, the degree of stretching by pushing and spreading is high, and cracks may occur on the upper surface of the stretched portion 4 in some cases.

It is desirable that the maximum width W53 of the protrusion 53 of the cutting edge is 0.3 to 3.0 times the sheet thickness T.
If it is 0.3 times or less, the extent of the spread is small and the stretched portion 4 is not too thin. If it exceeds 3.0 times, the upper surface of the stretched portion 4 may be cracked.

The shape of the cross section of the projection 53 of the cutting edge of the ruled line blade 5 may be a tip shape as shown in FIGS. 6 to 9 in addition to the shape shown in FIG.

[0030]

EXAMPLE The plastic sheet 1 has a thickness of 0.25.
mm of amorphous polyethylene terephthalate is used. As the ruled line blade 5, both the length L53 of the projection 53 of the cutting edge and the length L54 of the concave portion 54 of the cutting edge shown in FIGS.
5 mm, the cutting edge shape is a V shape with a cutting edge angle D of about 75 °, and the absolute height H530 of the convex portion 53 of the cutting edge is 0.3 mm.
When the bite height H53 is 0.24 mm, the bite maximum width W53 of the protrusion 53 of the cutting edge is about 0.19 mm.
Was used.

The plastic sheet 1 is placed on the iron plate 6 using the above-mentioned ruled line blade 5, and the ruled line blade 5 is cut from above the bite height H while the convex portion 53 of the cutting edge is pressed and spread.
53 was pressed to a portion of 0.24 mm, and as shown in FIG. 2, a folded ruled line 2 having a depth D3 of the deep groove 3 of 0.24 mm and an opening width W3 of the deep groove 3 of 0.19 mm was formed. The upper surface portion 41 of the extending portion 4 has a saddle shape, and the thickness T4 of the central portion 43 of the extending portion 4 is 0.21 mm.

The plastic sheet containing the folding ruled line thus obtained can be easily folded when folded 180 degrees from the folding ruled line 2, and a folding test in which the sheet is folded to the opposite side 360 degrees from this state is repeated 20 times. Also, there was no breakage from the folding ruled line 2, and the balance between the ease of bending and the strength was excellent.

In order to evaluate the ease of folding practically, as shown in FIG. 10, for example, as shown in FIG. Crushed flat, height A is 100mm, width B is 50m
The cylindrical body 10 having a thickness of 20 mm and a thickness C of 20 mm is manufactured, and the crushed cylindrical body 10 is caused by using an automatic box making machine (OMV Co., Ltd., VCV type), and the side flap 111 is formed.
As a result of a box making test in which the lid flap 112 was folded and closed to assemble a box, 60 boxes were made per minute. The same result was obtained when the side on which the ruled line was inserted was inside or outside the tubular body 10.

[0034]

According to the present invention, there is provided a plastic sheet having a folding ruled line, wherein the folding ruled line has a blade edge having a lengthwise direction.
Pressing a folded ruled line blade with uneven shape to the sheet
And formed while cutting and pushing the convex part of the blade edge.
Deep groove part, and stretched in the width direction by pushing and expanding the convex part.
And the stretched part formed alternately in the length direction
A plastic sheet with a folding ruled line, especially the bottom surface of the concave part of the blade edge touching the sheet.
Without stretching the sheet portion in the width direction.
Due to the effect of the stretched portion formed to be thin and thin, the folded creased plastic sheet of the present invention can form a crease having good bendability without breaking or breakage from the crease even if the average thickness of the entire crease is reduced. As a result, a thin and sharp bent portion is obtained.

Further, the length of the deep groove portion is set at 0. 3
Is to 3.0 times, the depth of the deep groove portion 0 of the sheet thickness. 5
1.0 to 1.0 times, and the opening width of the deep groove is 0.1 mm of the sheet thickness.
The length of the stretched portion is 0.3 to 3.0 times the sheet thickness.
Since it is 3 to 3.0 times, and the thickness of the stretched portion is smaller than the thickness of the sheet, a plastic sheet with a folded ruled line that balances ease of bending and difficulty of occurrence of breakage or breakage can be obtained. .

Further, since the stretched portion has a saddle-shaped upper surface, when the plastic sheet is folded from the folding ruled line, each stretched portion bends in a state where the corners are rounded, so that there is no danger of being caught by the fiber of the clothing. Also, the feel is good.

Then, the folded ruled-line blade having a concave-convex shape in the longitudinal direction is pressed against the plastic sheet so that the convex portion of the blade bites into the plastic sheet to form a deep groove portion while expanding the convex portion. By stretching the plastic sheet portion in the width direction and forming a stretched portion between the deep groove portions, the method of manufacturing a plastic sheet with a folded crease, the bent ruled line having the deep groove portion and the stretched portion is extremely formed. Because it can be easily formed, easy to bend and easy to adjust the strength, and does not require strong pressing force at the time of processing, it is possible to use many ruled line blades at once or use a single press type with ruled line blades and contour punching blades. It can be machined in large quantities by attaching it to the machine, and the height of the ruled line blade can be machined with the same dimensions, so there is no need for separate height adjustment unlike the conventional blade, so rational adjustment work is rational It is Hakare may be lower accuracy borders blade.

Further, the cutting edge has an uneven shape in the length direction, and the length of the convex portion of the cutting edge is 0.3 to 3.0 of the sheet thickness.
Double, the length of the concave portion of the blade edge is 0.3 to 3.0 of the sheet thickness.
Double-folded crease edge, wherein the bite height of the convex portion of the blade edge is 0.5 times or more the sheet thickness, and the maximum width of the bite of the convex portion of the blade edge is 0.3 to 3.0 times the sheet thickness. Is
Suitable for producing excellent folded ruled plastic sheets.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an example of a plastic sheet with a folding ruled line according to the present invention.

FIG. 2 is a sectional view taken along line II-II of FIG.

FIG. 3 is a sectional view taken along line III-III in FIG. 1;

FIG. 4 is a front cross-sectional view illustrating a method for manufacturing a plastic sheet with a folded crease according to the present invention and a folding crease blade.

FIG. 5 is a sectional view taken along line VV of FIG. 4;

FIG. 6 is a side sectional view showing another example of the folding ruled line blade of the present invention.

FIG. 7 is a side sectional view showing another example of the folding ruled line blade of the present invention.

FIG. 8 is a side sectional view showing another example of the folding ruled line blade of the present invention.

FIG. 9 is a side sectional view showing another example of the folding ruled line blade of the present invention.

FIG. 10 is a perspective view showing an example of a cylindrical body made of a plastic sheet with a folding ruled line according to the present invention.

FIG. 11 is a perspective view showing an example of a conventional plastic sheet containing a folding ruled line.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Plastic sheet 2 Bending ruled line 3 Deep groove part L3 Length of deep groove part D3 Depth of deep groove part W3 Opening part of deep groove part 4 Extension part 41 Top part L4 Length of extension part 5 Ruled line blade 53 Convex part of cutting edge L53 Cutting edge of cutting edge Length of the convex part H53 Height of the bite of the convex part of the blade H530 Absolute height of the convex part of the blade W53 Maximum width of the bite of the convex part of the blade 54 Concavity of the blade L54 Length of the concave part of the blade T T Sheet thickness T4 Extension part Thickness

──────────────────────────────────────────────────続 き Continued on the front page (58) Fields surveyed (Int. Cl. ⁶ , DB name) B29C 53/06 B31B 1/00-5/74 B26D 3/08

Claims (6)

(57) [Claims] 1. A plastic sheet containing a folding ruled line, wherein the folding ruled line has a cutting edge having an uneven shape in a length direction.
Press the folded ruled line blade with a shape to the sheet,
Deep groove formed while penetrating the convex part and expanding it
And formed by being stretched in the width direction by expanding the convex portion.
And the extending portions to be provided are provided alternately in the length direction.
A plastic sheet containing a folding ruled line. 2. An extended portion of the folding ruled line is a bent ruled line.
Make sure that the bottom surface of the concave
The sheet portion is expanded in the width direction by pushing out the convex portion of the blade edge.
It is characterized by being stretched to a thin wall
The plastic sheet with a folding ruled line according to claim 1.
To 3. The plastic sheet according to claim 1, wherein the extension has a saddle-shaped upper surface. 4. A deep crease is formed while pressing a folded ruled blade having a concave-convex shape in the longitudinal direction against a plastic sheet so as to bite a convex portion of the blade and expand the blade, and touch a bottom surface of a concave portion of the blade with the sheet. Without letting
A method for producing a folded ruled-lined plastic sheet, characterized in that the plastic sheet portion between the convex portions is stretched in the width direction by the pushing and spreading to form a stretched portion between the deep groove portions. 5. The cutting edge has an uneven shape in the length direction, the length of the projection of the cutting edge is 0.3 to 3.0 times the sheet thickness, and the length of the concave portion of the cutting edge is the sheet thickness. 0.3 to 3.0 times, the bite height of the protruding portion of the blade is 0.5 times or more of the sheet thickness, and the concave bottom surface of the blade does not touch the sheet,
The absolute height is larger than the bite height, and the maximum bite width of the protrusion of the blade edge is 0.3 to 3.0 of the sheet thickness.
Folded plastic sheet folding ruled blade. 6. A plastic case obtained by punching the plastic sheet according to claim 1 into a predetermined contour and bending the punched sheet.