JPH0839703A - Method for folding sheet material and female structure in blanking machine - Google Patents

Abstract

PURPOSE:To obtain a female structure in a blanking machine, in which a corrugated fibreboard to be folded along a folding line can be folded along the folding line without influence of corrugation. CONSTITUTION:In a blanking machine, a sheet material is disposed between a cutting die with a rule fixed and a female die having a rule insertion groove 19 to which the rule is inserted, the cutting die and the female die are moved close to each other, and a folding line is formed in the sheet material by inserting the rule into the rule insertion groove 19. In this blanking machine, recessed grooves 31 are formed in communication with the rule insertion groove 19 so that small-width openings 33 are formed by the recessed grooves 31.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for bending a sheet material and a structure of a female die in a punching machine.

[0002]

2. Description of the Related Art FIGS. 6 and 7 are sectional front views of a main part of a die and a female part of a conventional punching machine, and FIG. 8 shows a piece for a storage box punched by the punching machine. With a punching machine, for example,
As shown in FIG. 6, the die 5 is attached to the chase 3 of the upper slider 1, and the female die 11 is attached to the dead plate 9 of the lower surface plate 7. In addition, the chase 3
Is a general-purpose jig that is accurately positioned and fixed to the upper slider 1 of the punching machine, and the dead plate 9 is one of general-purpose jigs that is accurately positioned and fixed to the lower surface plate 7 of the punching machine. is there.

A cutting blade 13 and a ruled line 15 are embedded and fixed in the die 5, and a receiving surface 17 of the cutting blade 13 and a ruled line insertion groove 19 are formed in the female mold 11. Then, after a synthetic resin film, a thin paper, a cardboard, or the like sheet material 21 is placed on the female die 11, as shown in FIG. 7, the die 5 and the female die 11 are pressed to each other, and the cutting line 23 is cut. The tip of the blade 13 is the receiving surface 17
It is formed by pressure contact with. Further, the folding line 25 is formed at the center of the ruled line insertion groove 19 in the width direction by inserting the tip of the ruled line 15 into the ruled line insertion groove 19, and as a result, as shown in FIG. A piece 26 having a desired shape in which the line 23, the polygonal line 25 and the like are formed is obtained.

[0004]

On the other hand, cardboard is often used as the sheet material 21. Cardboard 21
The upper and lower liners 2101 and 21 as shown in FIG.
01 and a corrugated core 2105 sandwiched between the upper and lower liners 2101 and 2101 and having a so-called step 2103. Then, the step 2103 and the broken line 25
No problem arises when the two are orthogonal to each other, but a problem occurs when the step 2103 and the polygonal line 25 are parallel to each other, as shown partially broken in FIG. That is, although the folding line 25 is formed by the ruled line 15 at the center of the ruled line insertion groove 19 in the width direction, depending on the position of the step 2103 with respect to the folding line 25, when the sheet material 21 is folded, it is influenced by the step 2103 and the folding line 2103 is formed. There is a case where the sheet material 21 is not folded on the sheet 25 and the actually folded portion deviates from the folding line 25.

Particularly, in the case of a box which is glued using a box-making machine, when the step 2103 is parallel to the broken line 25 called a bag-making line that is folded by the machine, the regular completion shown in FIG. Since it cannot be folded along the polygonal line 25 like the box 28, a phenomenon called sticking and bending which tends to occur at an angle tends to occur, and as shown in FIG. 9B, the box 28 becomes distorted. there were. The present invention has been devised in view of the above circumstances, and an object of the present invention is to fold a sheet material in a straight line without being affected by the steps even when the sheet material is cardboard. It is an object of the present invention to provide a sheet material bending method and a female structure in a punching machine.

[0006]

In order to achieve the above-mentioned object, a method of folding a sheet material according to the present invention is a method of folding a sheet material along a fold line, in which the sheet material is spaced in the longitudinal direction of the fold line. It is characterized in that recesses are formed on both sides of the polygonal line at a plurality of locations. Further, the female die structure in the punching machine according to the present invention is such that a sheet material is arranged between a die having a fixed rule and a female die having a ruled insertion groove into which the rule is inserted, and the die and the female die are separated from each other. In a punching machine for forming a crease line on a sheet material by closely inserting the ruled line into the ruled line insertion groove, a concave groove is formed in the female mold so as to communicate with the ruled line insertion groove, and the ruled line is inserted by the concave groove. It is characterized in that a narrow opening is formed in the groove.

Further, according to the present invention, the concave groove is formed to extend linearly in a predetermined length in a direction intersecting the longitudinal direction of the ruled line inserting groove, and the concave groove crosses the ruled line inserting groove to form the ruled line. It is characterized in that it is formed across both sides of the insertion groove in the width direction. Further, the present invention is characterized in that a plurality of the concave grooves are formed at intervals in the longitudinal direction of the ruled line inserting groove. Further, the present invention is characterized in that the concave groove is formed with a width smaller than a width of the ruled line inserting groove. Also,
The present invention is characterized in that a cutting blade is fixed to the cutting die, and a receiving surface on which the cutting blade abuts is provided on the female die.

[0008]

[Function] When a ruled line is inserted into the ruled line insertion groove, the corner formed by the ruled line insertion groove and the upper edge of the concave groove or the upper edge portion of the concave groove in the vicinity of the opening hits the sheet material to form a polygonal line. Is formed, and a deformed portion such as a concave portion is formed in the sheet material portion on the side of the polygonal line. It is considered that the polygonal line is a collection of a plurality of polygonal lines that are divided at intervals in the longitudinal direction by the deformed portions. When the sheet material is folded along the fold line, even if a force to shift from the fold line acts, this force is considered to be absorbed and dispersed by the deformed portion, and the sheet material is folded along the fold line. .

[0009]

The bending method according to the present invention will be described below together with the female die of the punching machine. FIG. 1 is a plan view of a female die according to an embodiment, and FIGS. 2A to 2D are lines AA and BB in FIG.
The line, CC line, and DD line sectional drawing are shown. In FIGS. 1 and 2, 11 is a female die, 19 is a ruled line insertion groove, and
Has a predetermined width and depth, and a receiving surface 17 is formed at an appropriate position on the female mold 11. A plurality of concave grooves 31 are formed in the ruled line insertion groove 19 at intervals in the longitudinal direction of the ruled line insertion groove 19. The width of the concave groove 31 is smaller than that of the ruled line inserting groove 19, and the depth thereof is the same as that of the ruled line inserting groove 19. The concave groove 31 is formed so as to extend a predetermined length in a direction orthogonal to the longitudinal direction of the ruled line inserting groove 19 and is formed so as to extend across both sides of the ruled line inserting groove 19 in the width direction. The groove 31 communicates,
An opening 33 is defined in a communicating portion between the ruled line insertion groove 19 and the concave groove 31. Then, the ruled line insertion groove 19 is formed in the opening 33.
The corner 35 is formed by the upper edge 1901 and the upper edge 3101 of the groove 31 intersecting each other.

According to this embodiment, when the cardboard 21 is placed on the female die 11 and the die 5 and the female die 11 are brought into pressure contact with each other, the tip of the cutting blade 13 comes into pressure contact with the receiving surface 17 as in the conventional case. A cut line 23 is formed, and the tip of the ruled line 15 is inserted into the ruled line insertion groove 19 to form a broken line 25 at the center of the ruled line insertion groove 19 in the width direction. When the ruled line 15 is inserted into the ruled line insertion groove 19, the corner portion 35 and the upper edge 3101 of the concave groove 31 near the opening 33 hit the back surface of the corrugated board 21, and as shown in FIG. Point-shaped recesses 41 that are slightly recessed are formed on both sides of the polygonal line 25 at a plurality of locations spaced apart in the longitudinal direction of 25.

Due to the recess 41, the polygonal line 25 is considered to be a collection of a plurality of polygonal lines that are separated at intervals in the longitudinal direction. Therefore, when the corrugated board 21 is folded along the fold line 25, the step 2103 is located near the fold line 25 and the step 2103 is located.
Even if it is affected by, it is considered that the force to deviate from the polygonal line 25 is absorbed and dispersed by each recess 41, and the corrugated board 21 is folded along the polygonal line 25.

The number of the concave grooves 31 for forming the concave portions 41 may be one, for example, when the length of the ruled line inserting groove 19 is short.
The number of the concave grooves 31 depends on the length of the ruled line inserting groove 19 or the step 2
It is appropriately determined in consideration of the influence of 103 and the like. Further, in the embodiment, the case where the concave groove 31 is linearly extended and formed so as to extend over both sides of the ruled line inserting groove 19 has been described, but the concave grooves 31 on both edges of the ruled line inserting groove 19 are the same as in the example. The phases do not have to be the same, and the grooves 31 on both edges may be shifted in phase so that the grooves 31 are alternately formed on both edges. Also,
The extending direction of the concave groove 31 is not limited to the direction orthogonal to the ruled line inserting groove 19 as in the embodiment, and in short, the narrow opening 33 may be formed in the ruled line inserting groove 19, for example, The circular recessed groove 31 may be formed, and the narrow opening 33 may be formed by communicating the edge of the circular recessed groove 31 with the ruled line insertion groove 19.

FIG. 4 is a plan view of a female die according to the second embodiment, and FIG. 5 is a sectional view taken along the line AA of FIG. In the second embodiment, a narrow strip-shaped portion 51 is left on both sides of the ruled insertion groove 19 on the receiving surface 17 of the female die 11, and a groove having the same depth as the ruled insertion groove 19 is left outside the strip-shaped portion 51. 53 is formed, and the strip portion 51 is formed.
The grooves 53 and the groove 53 are spaced apart in the longitudinal direction of the
An opening 57 is defined in a communicating portion between the ruled line insertion groove 19 and the concave groove 55. A corner 59 is formed in the opening 57 by the upper edge of the ruled line insertion groove 19 and the upper edge of the concave groove 55 intersecting with each other. Also according to the second embodiment as described above, when the ruled line 15 is inserted into the ruled line insertion groove 19, the corner portion 59 and the upper edge portion of the concave groove 55 near the opening 57 hit the back surface of the corrugated cardboard 21 and are shown in FIG. Like, line 25
The dot-shaped recesses 41 are formed on both sides of the. Further, according to the second embodiment, since the strip-shaped portion 51 forming the corner portion 59 is narrow, the corner portion 59 sharply cuts into the back surface of the corrugated board 21, and the dot-shaped recess 41 is formed more effectively. .

According to the female die of the present invention, when the ruled line is inserted into the ruled line insertion groove, since the corners and the upper edge portion of the concave groove near the opening function as resistance, the corrugated board is prevented from shifting. It is possible to accurately form a polygonal line at the center of the ruled line insertion groove in the width direction. Further, the present invention is not limited to the case where the sheet material is corrugated cardboard, and is naturally applied to all sheet materials.

[0015]

As is apparent from the above description, the method for folding a sheet material according to the present invention according to the present invention is a sheet having a space in the longitudinal direction of the folding line when folding the sheet material along the folding line. The recesses were formed on both sides of the polygonal line at a plurality of points on the material. Further, the female die structure in the punching machine according to the present invention is such that a sheet material is arranged between a die having a fixed rule and a female die having a ruled insertion groove into which the rule is inserted, and the die and the female die are separated from each other. In a punching machine for forming a crease line on a sheet material by closely inserting the ruled line into the ruled line insertion groove, a concave groove is formed in the female mold so as to communicate with the ruled line insertion groove, and the ruled line is inserted by the concave groove. A narrow opening was formed in the groove. Therefore, even when the corrugated board is bent, it is possible to bend the corrugated board along the polygonal line without being affected by the step.

[Brief description of drawings]

FIG. 1 is a plan view of a main part of a female mold of the present invention.

2 (A) to 2 (D) are lines AA and B in FIG.
FIG. 6 is a cross-sectional view taken along the line B, the line C, and the line D;

FIG. 3 is a plan view of a polygonal line and a recess formed on a corrugated board by the female die of the present invention.

FIG. 4 is a plan view of a main part of a female die according to a second embodiment.

5 is a cross-sectional view taken along the line AA of FIG.

FIG. 6 is a front view of essential parts of a die and a female part of the punching machine.

FIG. 7 is a front view of essential parts of a die and a female die portion of the punching machine.

FIG. 8 is a development view of a piece for a packaging box punched by a punching machine.

FIG. 9A is a plan view of a regular-shaped packaging box, FIG.
(B) is a plan view of the packaging box in which the fold lines are displaced.

[Explanation of symbols]

 5 Cutting dies 11 Female dies 13 Cutting blades 15 Ruled lines 17 Receiving surface 19 Ruled line insertion grooves 31,55 Recessed grooves 33,57 Openings 41 Recessed parts

Claims (6)

[Claims] 1. When folding a sheet material along a fold line, recesses are formed on both sides of the fold line at a plurality of positions of the sheet material that are spaced in the longitudinal direction of the fold line. How to bend the material. 2. A sheet material is arranged between a die having a fixed rule and a female mold having a rule insertion groove into which the rule is inserted,
In a punching machine in which a die and a female mold are brought close to each other and the ruled line is inserted into a ruled line insertion groove to form a fold line in a sheet material, in the female mold, a groove is formed by communicating with the ruled line insertion groove,
A female structure in a punching machine, wherein a narrow opening is formed in the ruled line insertion groove by the groove. 3. The groove is formed to extend linearly in a predetermined length in a direction intersecting the longitudinal direction of the ruled groove, and the groove crosses the ruled groove and the width of the ruled groove. The female structure in the punching machine according to claim 2, wherein the female structure is formed so as to straddle both sides in the direction. 4. The female structure in a punching machine according to claim 2, wherein a plurality of the concave grooves are formed at intervals in the longitudinal direction of the ruled line inserting groove. 5. The female structure in a punching machine according to claim 2, wherein the groove is formed with a width smaller than the width of the ruled line insertion groove. 6. The female in the punching machine according to claim 2, 3, 4 or 5, wherein a cutting blade is fixed to the punching die, and a receiving surface for contacting the cutting blade is provided on the female die. Type structure.