JP2010017955A - Lead blade - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a lead blade, can prevent bending of a sheet material at a cut line while the sheet material is not crushed at a half-cut part. <P>SOLUTION: In the lead blade having a high blade part 11a for forming a full-cut part and a low blade part 11b for forming a half-cut part for forming, in a sheet material such as corrugated board, a lead in which the full-cut part extending to both sides of the sheet material and the half-cut part cut to the middle in its thickness direction are alternately continued, the low blade part 11b includes a plurality of protruding parts 11c, each of the protruding part 11c having a gradient at its cutting edge, and a recessed part 11d is provided between the adjacent protruding parts 11c. Since the protruding part 11c of the low blade part 11b bites into the sheet material successively from a portion with high cutting edge, the sheet material such as corrugated board is never strongly pressed or crushed, and a connection part is formed in the half-cut part by the recessed part 11d, whereby the sheet material is hardly bent in a position other than a predetermined position when making a box from the sheet material, and body bulging in stacking can be also prevented. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a lead blade for inserting a lead in which full cut portions and half cut portions are alternately interrupted into a sheet material such as cardboard.

  In general, as a wrap-round cardboard box for packaging beverage cans, as shown in FIG. 8, a pair of elevation plates 51 and a plane plate 52 arranged in series via a pair of upper and lower ridge ruled lines 50 are folded and accumulated. What encloses the can C, forms a peripheral wall by joining at the passage piece 53, and sticks and seals the end plates 54 and 55 extending from the upright plate 51 and the flat plate 52 is used.

  An opening tear strip 56 parallel to the ridge ruled line 50 is provided on the end plate 54 on the elevation plate 51 of the cardboard box. The center portion of the elevation plate 51 is provided with an end portion of the tear strip 56 at the time of opening. A cutting start portion 57 for picking is provided.

  Here, the tear band 56 is formed by two opposing straight cut lines 56a, and this cut line 56a is generally formed by a liner cut that cuts only the liner on the back side when a corrugator is used to manufacture a corrugated cardboard. Although it is inserted, in order to prevent displacement from the start portion 57, it is also conceivable to use a lead inserted by punching when the sheet material is punched.

  At this time, as shown in FIG. 9, a lead blade 61 in which a high blade portion 61a and a low blade portion 61b having a flat blade edge are alternately formed is provided in the die, and the corrugated cardboard sheet material S is formed by the high blade portion 61a. The full cut portions penetrating the front and back are respectively inserted into the half cut portions cut from the back side of the sheet material S to the middle in the thickness direction by the low blade portions 61b, and the full cut portions and the half cut portions are alternately interrupted.

  However, when the lead blade 61 as described above is used, the corrugated cardboard is crushed without being cut at the initial stage of cutting at the low blade portion 61b, and the sheet material is not cut at the ridge line ruled line 50 but at the cut line 56a at the time of box making. There is a risk that the box will be bent, resulting in poor box making.

  Further, when a plurality of sheets are stacked in a packaged state and the load of the upper cardboard box is applied to the lower cardboard box, the riser plate 51 may be swollen, and the aesthetics at the time of display sales may be impaired.

  Then, this invention makes it a subject to provide the lead blade which can prevent the sheet | seat material from being crushed in a half cut part, and the bending of the sheet | seat material in a score line can be prevented.

  In order to solve the above-mentioned problem, the present invention puts in a sheet material such as corrugated cardboard a lead in which a full cut portion penetrating the front and back and a half cut portion cut in the middle in the thickness direction are alternately interrupted. In a lead blade in which a high blade portion for inserting a full cut portion and a low blade portion for inserting a half cut portion are alternately formed, a plurality of convex portions are provided on the low blade portion, and a gradient is formed on the edge of each convex portion. And a concave portion is provided between adjacent convex portions.

  In the lead blade according to the present invention, each convex portion of the low blade portion is sequentially cut into the sheet material from a portion having a high blade edge, so that the sheet material such as cardboard is strongly pressed and cut without being crushed. In addition, a connecting portion is formed in the half-cut portion by the concave portion, and when making a box from a sheet material, it is possible to prevent the occurrence of defective box making due to bending at a position other than a predetermined position, and it is possible to prevent swelling of the box at the time of stacking .

  Also, when opening the box with the tear line cut line with this lead blade, pulling the tear band from its starting part cuts the cardboard so that the entire cut part is connected along the half-cut part, and the tear band becomes Can be opened easily without tearing along the way.

  DESCRIPTION OF EMBODIMENTS Hereinafter, an embodiment of a corrugated cardboard box in which a tear line is cut with a lead blade according to the present invention will be described with reference to the accompanying drawings.

  This cardboard box is of the wrap round type used for packaging beverage cans, and is formed from the sheet material shown in FIG. In this sheet material, each pair of elevation plates 2 and plane plates 3 are alternately arranged via ridge ruled lines 1, and passage pieces 4 are arranged continuously to one of the elevation plates 2 via ridge ruled lines 1. ing. End plates 5 and 6 are connected to both ends of the upright plate 2 and the flat plate 3, respectively.

  The elevating plate 2 is provided with a tear strip 7 for opening parallel to the ridge ruled line 1, and the tear strip 7 reaches the edge of the end plate 5. In the central portion of the upright plate 2, a cut start portion 8 is provided for picking an end portion of the tear strip 7 when opened.

  Here, the tear band 7 in the elevation plate 2 is formed by two symmetrical cut lines 7A, and each cut line 7A is a lead in which full cut portions 7a and half cut portions 7b are alternately interrupted. The full cut portion 7a penetrates the front and back of the cardboard.

  In the half-cut portion 7b, half-cuts 7c in which the cardboard is cut from the back side to the middle in the thickness direction and a plurality of connecting portions 7d without cut are alternately formed, and between the full-cut portion 7a and the half-cut portion 7b. 7d is also formed.

  The cut start portion 8 is formed by placing all cuts 8a penetrating the front and back of the cardboard into a deformed H shape.

  A die cutter for manufacturing the cardboard box is equipped with a die D as shown in FIG. 2 for punching a sheet material from the back side. This cutting die D is provided with a lead blade 11 for inserting the cut line 7A of the tear strip 7 in parallel with the linear pressing member 10 for inserting the ridge ruled line 1 at the boundary between the elevation plate 2 and the plane plate 3. Subsequently, all the cutting edges 12 into which the cuts 8a of the cutting start portion 8 are to be provided are provided in the central portion.

  Here, in the lead blade 11, as shown in FIG. 3, the high blade part 11a and the low blade part 11b are alternately formed in the blade edge | tip part. The low blade portion 11b is provided with a plurality of convex portions 11c, and a concave portion 11d is provided between adjacent convex portions 11c. Moreover, the recessed part 11d is provided also between the high blade part 11a and the low blade part 11b.

  Then, a gradient is provided at the edge of each convex portion 11c so that the central portion has a high mountain shape.

  In this figure, for example, when punching a sheet material S made of corrugated cardboard having a thickness of about 2 mm, the blade height α of the high blade portion 11a is 0.7 mm, and the convex portion 11c of the high blade portion 11a and the low blade portion 11b. The step β with the upper end is set to 0.2 mm, the step γ between the lower edge of the convex portion 11c of the high blade portion 11a and the low blade portion 11b is set to 0.5 mm, and the width δ of the concave portion 11d is 0.2 to 0.9 mm. It is good to set to.

  When the sheet material S is punched with such a cutting die D, as shown in FIG. 4, in the lead blade 11, the high blade portion 11a penetrates the sheet material S supported by the support material 15 such as cork from the back side to the front side. The convex portion 11c of the low blade portion 11b cuts the sheet material S from the back side to the middle in the thickness direction, and the full cut portion 7a of the cut line 7A and the half cut 7c of the half cut portion 7b shown in FIG.

  At this time, as shown in FIG. 3, the convex portion 11 c of the low blade portion 11 b is sequentially cut into the sheet material S from a high portion of the blade edge, so that the sheet material S is strongly pressed and crushed at the initial stage of the cutting. There is nothing. In addition, the concave portion 11d does not cut the sheet material S, and a connection portion 7d that is not cut is provided inside the half cut portion 7b and between the full cut portion 7a and the half cut portion 7b.

  Even if the blade edge of the high blade portion 11a is worn down and the blade height is lowered due to long-term use, the cutting of the full cut portion 7a and the half cut portion 7b is caused by the gradient provided on the convex portion 11c of the low blade portion 11b. The balance of inclusion does not change greatly.

  In addition, the blade edge of the convex part 11c of the low blade part 11b has a shape inclined from one side to the other side as shown in FIG. 5 (a) or an arc shape at the center part as shown in FIG. 5 (b). 5C, as shown in FIG. 5 (c), both ends are high and the center is low. The effect that it will not be crushed by being pressed strongly can be acquired.

  Moreover, in each low blade part 11b, it is good also as a shape which has two or four or more convex parts 11c other than the shape which has the three convex parts 11c illustrated.

  Such a lead blade can be easily manufactured by a wire cut electric discharge machine, and can be manufactured not only for a flat plate die cutter but also for a rotary die cutter.

  Now, when a beverage can is packaged by assembling the sheet material punched by the above-described die cutting, a pair of elevation plates are used along the ridge line 1 as shown in FIG. 6 using a wrap round caser. 2 and the flat plate 3 are bent, the accumulated can C is wrapped, a peripheral wall is formed by joining at the passage piece 4, and the end plates 5 and 6 are bonded together and sealed.

  At the time of making the box, in the above-mentioned corrugated cardboard box, the corrugated cardboard is not crushed at the cut line 7A of the tear strip 7 at the half cut part 7b, and between the full cut part 7b and between the full cut part 7a and the half cut part 7b. 7d is formed, the elevation plate 2 is less likely to be bent inward at the score line 7A as shown in FIG. 7, and is accurately bent along the ridge ruled line 1 with the plane plate 3, Occurrence of defective box making can be prevented.

  In addition, the fact that the half cut portion 7b of the cut line 7A is inserted from the back side of the corrugated cardboard also contributes to prevention of bending at the cut line 7A of the elevation plate 2.

  Furthermore, when manufacturing the sheet material for the corrugated cardboard box, the cut line 7A of the tear strip 7 and the cut 8a of the cut start portion 8 are put in the same die, so that their positional relationship is not shifted, and the conventional corrugator Compared to the manufacturing method in which the cut 8a is made with a die cutter after the liner cut at, the defect rate can be greatly reduced.

  When the tear strip 7 is pulled from the cut start portion 8 at the time of opening, the full cut portion 7a is connected along the half cut portion 7b without being unsealable and being unsealable like a line cut with a liner cut. Thus, the cardboard is cut and can be easily opened.

  On the other hand, when a plurality of cardboard boxes are stacked in the state of packaging in the physical distribution process, a large load acts on the lower cardboard box. Even in such a state, the cardboard is crushed by the half-cut portion 7b. Since it is not performed or has the connecting portion 7d, buckling of the elevation plate 2 at the score line 7A is suppressed, and swelling of the body is prevented.

  In each of the above embodiments, the case where a straight cut line is provided as a tear strip in a cardboard box is illustrated, but when a wavy cut line is also used, if a lead blade as described above is used, It is possible to effectively prevent the buckling strength from being lowered, and it is possible to improve the effect of preventing the occurrence of boxing defects and the swelling of the body during stacking.

  Further, not only corrugated cardboard but also a sheet material made of a single paper such as paperboard, or a plastic sheet material such as polypropylene, can be scored by the same lead.

  Furthermore, this lead blade is not only applied to the tear line cut line for the purpose of resisting buckling while ensuring cutability as in the above embodiment, but also in a folding bottom assembly, etc. It can also be used when putting a ruled line that is bent in the direction opposite to the cut side.

The reverse view which shows the sheet material made from corrugated board using the lead blade concerning this invention The perspective view which shows the principal part of the cutting die provided with the lead blade same as the above Schematic side view showing the cutting process into the sheet material by the lead blade same as above Schematic sectional view showing the state of cutting into the sheet material by the lead blade same as above Side view showing various forms of lead blade The perspective view which shows the assembly sealing state of a cardboard box same as the above Partial perspective view showing the box making process The perspective view which shows the assembly sealing state of the cardboard box which put the conventional score line Schematic side view showing the process of cutting into sheet material with a conventional lead blade

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Edge part ruled line 2 Elevation board 3 Plane board 4 Passage piece 5,6 End plate 7 Tear strip 7A Cut line 7a Full cut part 7b Half cut part 7c Half cut 7d Connection part 8 Start part 8a Cut part 10 Pressing member 11 Lead blade 11a High blade part 11b Low blade part 11c Convex part 11d Concave part 12 Full cutting edge D Cutting die S Sheet material

Claims (1)

  In order to put a lead in which the full cut part penetrating the front and back and the half cut part cut into the middle of the thickness direction alternately in the sheet material, a high blade part (11a) for inserting the full cut part, In the lead blade alternately formed with the low blade portion (11b) for inserting the half-cut portion, the low blade portion (11b) is provided with a plurality of convex portions (11c), and the blade edge of each convex portion (11c) is provided. A lead blade characterized by forming a gradient and providing a recess (11d) between adjacent protrusions (11c).

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