JP6667821B1 - Die removal of sheet - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet die capable of reliably punching a groove-shaped portion of a blank sheet so as not to connect cutting chips. SOLUTION: The cutting blade member 10 is a blade formed from a strip-shaped steel plate, and a substrate 20 in which the cutting blade member 10 is implanted. The cutting blade member 10 has a linear contour facing each other. In a punching die having a straight side portion 11 to be punched and a curved portion 12 which is continuous with the curved portion 12 to be punched into a curved contour, the cutting edge of the straight side portion 11 is corrugated so that a linear contour has a continuous waveform of a predetermined pitch. It is assumed to be a wavy cutting edge 11a extending, and the cutting edge of the bending portion 12 is a non-wavy cutting edge 12a extending in conformity with a curved contour without waviness. [Selection diagram] FIG.

Description

  BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet die for punching a sheet such as a cardboard.

  For example, as a cardboard box for collectively packaging beverage cans, as shown in FIG. 6, a top plate 51, a pair of side plates 52 and a bottom plate 53 are continuously connected in a tubular shape via a joint piece 54, and a side plate 52 is provided. Are attached to a pair of inner flaps 55 which are extended from each of them and bent so as to face each other, and outer flaps 56 which extend from each of the top plate 51 and the bottom plate 53 and are bent so as to face each other. A cardboard box is used that is fitted and closed at the end.

  In this cardboard box, in order to prevent injuries in which the hand is cut by a sharp cutting edge of the cardboard during transportation or opening, the edges of each part are formed into a continuous waveform with a minute pitch (continuous waveform is not shown).

  Such a flat blank sheet for a corrugated cardboard box is manufactured by punching out a corrugated cardboard sheet by a die as shown in FIG. 7 attached to a die cutter. In this die cutting, a cutting blade member 30 of a blade made of a strip-shaped steel plate and a ruled member 41 for pressing a corrugated cardboard sheet in a line shape are implanted in a board 20 which is a wooden plywood. Of the blank sheet is punched out and crease lines are formed to form each part.

  As shown in FIG. 8, in this punching die, the portions forming the contours of the flaps 55 and 56 of the cutting blade member 30 are, as shown in FIG. 8, a straight side portion 31 for punching a corrugated cardboard sheet into a linear contour, and the corrugated cardboard sheet is curved. And a curved portion 32 that is punched into a contour.

  Here, the cutting blade member 30 includes a blade base 30a which is press-fitted into the groove 21 of the substrate 20, and a bladed part 30b which is tapered and thinned from the blade base 30a to the tip to cut the corrugated cardboard sheet. It is composed of The cutting edge 30b is formed with cutting edges of the right side portion 31 and the curved portion 32. Each of these cutting edges has a waveform for punching the contour of the blank sheet into a continuous waveform of a minute pitch over the entire length of the cutting blade member 30. The cutting edges are 31a and 32a.

  The blade edge of the cutting blade member 30 having the continuous waveform formed as described above is abutted against the face plate of the die cutter, and punches a blank sheet placed on the face plate into a predetermined shape.

  In addition, for the purpose of preventing injuries that the hand is cut at the cutting edge of the corrugated cardboard, a die for punching a corrugated cardboard box or a blank sheet having a flap edge at a continuous pitch with a fine pitch is disclosed in Patent Document 1 below. 2.

JP 2012-1264 A JP 2012-6648 A

  By the way, since the cutting edge member 30 of the above-mentioned die shape is formed by pressing the bladed portion 30b over the entire length to form the corrugated cutting edges 31a and 32a, the hardness increases due to work hardening, while the toughness increases. It is scarce.

  When the curved portion 32 is formed by bending such a cutting blade member 30, cracks and breaks are easily generated in the corrugated cutting edge 32 a, and the height of the corrugated cutting edge 32 a from the substrate 20 becomes non-uniform. A gap is easily generated between the corrugated cutting edge 32a and the face plate against which the corrugated cutting edge 32a abuts, and the corrugated cutting edge 32a does not uniformly and normally contact the face plate.

  According to the corrugated cutting edge 32a having such a defect, the blank sheet cannot be punched into a predetermined shape, or when the surrounding chip is separated from the contour of the punched blank sheet and pushed down, the contour of the blank sheet is reduced. A part and the scraps remain connected and do not completely separate, and the scraps hang from the blank sheet, which may be caught by a conveyor or a packaging machine in a downstream process.

  Such a punching defect is particularly likely to occur in a groove-like portion called a slot between adjacent flaps in a blank sheet. As a countermeasure, only a portion to be punched out in a groove-like shape is used to cut a non-corrugated cutting edge. A die having a blade member implanted in a substrate may be used.

  However, in this die cutting, a slight gap or displacement occurs at a joint portion between the cutting blade member of the corrugated cutting edge and the cutting member of the non-corrugated cutting edge, and the blank sheet is not cut at this portion, and continuous cutting is performed. Therefore, there is a possibility that the punching state becomes unstable, for example, a punching defect occurs due to this.

  In view of the above, an object of the present invention is to provide a die for a sheet that can be normally punched into a predetermined shape of a blank sheet, and in particular, a groove-shaped part of the blank sheet can be reliably punched out without cutting chips. And

In order to solve the above problems, the present invention includes a cutting blade member which is a blade formed from a strip-shaped steel plate, and a substrate on which the cutting blade member is implanted,
The cutting member is arranged in pairs, and straight sides having a waveform cutting edge punching the contour to form a continuous waveform having a predetermined pitch in a straight linear sheet, so as to be sandwiched between the two straight sides In the die cutting of a sheet having a curved portion with a non-corrugated cutting edge that punches the sheet into a curved contour that does not form a continuous waveform ,
The two right side portions respectively extend in the same direction so as to face each other via the curved portion, corresponding to both side edges of the groove portion formed in the sheet,
The curved portion is bent in a semicircular shape so that both ends, which are connection portions with the both right side portions, face in the same direction, corresponding to the valley bottom of the groove portion formed in the sheet . It is.

Further, the cutting blade member is configured by a blade base portion that is press-fitted into the groove of the substrate, and a bladed portion that becomes thinner in a tapered shape from the blade base portion to the tip end,
The corrugated cutting edge and the non-corrugated cutting edge are formed on the bladed portion.

  In addition, the corrugated cutting edge and the non-corrugated cutting edge are formed such that a stretch length obtained by linearly extending the pitch of the corrugated cutting edge by 1 is shorter than a stretching length obtained by linearly extending the curved non-corrugated cutting edge. It was decided.

  Further, the non-corrugated cutting edge in the curved portion has a shape curved with a radius of curvature larger than the radius of curvature of the top of the waveform of the corrugated cutting edge in the right side portion.

  In the sheet cutting die according to the present invention, the cutting edge of the portion to be a curved portion is set as a non-corrugated cutting edge by setting only the cutting edge of a portion to be a right side portion of the cutting blade member to a non-corrugated cutting edge. Prevents the reduction of toughness due to the formation of a continuous waveform in the press, bends the cutting blade member into a shape corresponding to the curved portion while maintaining the initial toughness at the time of forming the cutting edge, and implants it in the substrate Therefore, the phenomenon that cracks and breakage occur at the cutting edge of the curved portion and the phenomenon that the height from the substrate to the cutting edge becomes uneven are suppressed, and the punching of the sheet ensures that the cutting edge uniformly and normally strikes the face plate of the die cutter. become.

  For this reason, when punching a sheet, the cutting edge of the curved portion of the cutting blade member is continuous with a linear waveform having a continuous waveform punched by the right side portion without deteriorating sharpness, and the sheet is reliably formed by the curved portion. In addition, it is possible to prevent the occurrence of a punching defect in which the punching is performed accurately and the blanks remain connected to the blank sheet.

  In addition, it is easy to bend the curved portion of the cutting blade member and to cut the groove of the substrate into which the cutting member is to be implanted, and to smoothly implant the curved portion of the cutting blade member into the groove of the substrate. It can be carried out. Then, the side surface of the curved portion of the cutting blade member is pressed against the side surface of the engraved groove of the substrate without any gap, so that the cutting blade member is prevented from falling off from the substrate during punching of a sheet. These functions and effects become more remarkable when the curved portion of the cutting blade member has an arc shape.

  In addition, the curved portion of the blank sheet punched out has an arc shape, so that the appearance is improved.

  Further, when the extension length and the radius of curvature of the curved portion of the cutting blade member are set to be large, the blank sheet is punched smoothly at the non-corrugated cutting edge of the curved portion, and the groove-shaped portion between the adjacent flaps in the blank sheet is opposed. The distance between the side edges becomes large, and the swarf becomes large, so that it can be easily removed.

The perspective view which shows the state before bending of the cutting blade member of the sheet | seat removal type which concerns on this invention. The perspective view which shows the state after bending of the same cutting blade member. Perspective view showing a cutting die having the same cutting blade member implanted in a substrate. Enlarged plan view comparing one pitch of the corrugated cutting edge of the straight side portion with the length of the non-corrugated cutting edge of the curved portion extended. An enlarged plan view comparing the radius of curvature of the top of the corrugated cutting edge of the straight side portion with the radius of curvature of the non-corrugated cutting edge of the curved portion. Perspective view of a cardboard box in which the edges of each part have a continuous waveform with a minute pitch Top view showing die removal of cardboard box Perspective view showing a cutting die in which a conventional cutting blade member is implanted in a substrate.

  Hereinafter, embodiments of the present invention will be described with reference to the accompanying drawings.

  The cutting blade member 10 shown in FIG. 1 is a blade that punches out a corrugated cardboard sheet when manufacturing a flat blank sheet for a corrugated cardboard box, and is made of a strip-shaped steel plate. It is in a state of extending.

  In the portion forming the outline of the flap of the cardboard box, the cutting blade member 10 is bent as shown in FIG. 2 and is implanted in a groove 21 formed in the substrate 20 as shown in FIG. In this portion, the cutting blade member 10 includes a straight side portion 11 that is linear, and a curved portion 12 that is integrated with the straight side portion 11 and is in a curved state.

  The right side portion 11 is disposed at a portion forming each of the opposing side edges of the cut-out groove portion between the adjacent flaps, and at a portion forming the respective leading edge of each flap. Are arranged in a portion forming a trimmed semicircular valley bottom of a cut-out groove-shaped portion between adjacent flaps, and a portion forming a trimmed arc-shaped rounded corner of the flap. .

  The cutting edge of the right side portion 11 is a wavy cutting edge 11a extending while waving so as to form a straight contour into a continuous waveform of a predetermined pitch, and the cutting edge of the curved portion 12 matches the curved contour without waving. The non-corrugated cutting edge 12a extends.

  The cutting blade member 10 includes a blade base 10a that is press-fitted into the groove 21 of the substrate 20, and a bladed part 10b that becomes thinner in a tapered shape from the blade base 10a to the tip. A corrugated cutting edge 11a and a non-corrugated cutting edge 12a are formed on 10b.

Here, in FIG. 4, a right side portion 11 that forms the opposing side edge of the punched groove portion between the adjacent flaps and a curved portion 12 that forms the bottom of the groove portion are shown. 11 one pitch (adjacent vertices Pt, between Pt) of the waveform cutting edge 11a of the stretch stretched length _{L 1} which stretched in a straight line, the extended end point Ae of non waveform cutting edge 12a curved in a semicircular arc, between Ae into linear to be shorter than the length L _2, the waveform cutting edges 11a and non-waveform cutting edge 12a is formed.

  In addition, when the punching target is a corrugated cardboard sheet, the pitch of the corrugated cutting edge 11a in the right side portion 11 is set to about 0.2 mm to 8.0 mm, depending on the thickness and paper quality of the corrugated cardboard sheet and the form of the corrugated cardboard box. Set an appropriate pitch. If the pitch is too large, it is difficult to obtain the effect of preventing hand cut.

As shown in FIG. 5, the non-corrugated cutting edge 12 a in the curved portion 12 has a shape curved with a radius of curvature r ₂ larger than the radius of curvature r ₁ of the top of the waveform of the corrugated cutting edge 11 a in the right side portion 11. I have.

  In the above-described die cutting of a corrugated cardboard sheet, the cutting blade member 10 that forms the contour of the groove-like portion of the blank sheet is a corrugated cutting edge 11a only at the portion that becomes the right side portion 11, and the cutting edge member that becomes the curved portion 12 is formed. Is set as the non-corrugated cutting edge 12a, so that the cutting edge of the portion to be the curved portion 12 is prevented from having a decrease in toughness due to the formation of a continuous waveform by pressing, and the initial toughness at the time of forming the cutting edge is maintained. Since the bent portion 12 is bent and implanted in the substrate 20, the occurrence of cracks or breakage at the cutting edge of the bent portion 12 is prevented, and the phenomenon that the height from the substrate 20 to the cutting edge is not uniform is suppressed. .

  For this reason, when punching out a corrugated cardboard sheet and forming a groove-like portion in the contour of the blank sheet, the cutting edge of the curved portion 12 that punches out the contour of the bottom of the groove-like portion does not deteriorate sharpness, The corrugated cardboard sheet is reliably and normally punched by the curved portion 12 continuously with the continuous waveform having the continuous waveform punched by the punch 11, and the punching defect remains connected to the bottom of the groove portion. Is prevented.

  Further, the bending process of the curved portion 12 of the cutting blade member 10 and the processing of the groove 21 of the substrate 20 into which the cutting blade member 10 is implanted can be easily performed. The work of implanting in the groove 21 can also be performed smoothly. Then, the side surface of the curved portion 12 of the cutting blade member 10 is pressed against the side surface of the groove 21 of the substrate 20 without any gap, thereby preventing the cutting blade member 10 from falling off the substrate 20 at the time of blank sheet punching. These functions and effects become more remarkable when the curved portion of the cutting blade member has an arc shape.

  In addition, the curved portion of the blank sheet punched out has an arc shape, so that the appearance is improved.

Furthermore, when stretched length L ₂ and radius of curvature r ₂ of the curved portion 12 of the cutting member 10 is set larger, punching the blank sheet in a non-waveform cutting edge 12a of the bending portion 12 is performed smoothly, adjacent in the blank sheet The distance between the opposing side edges of the groove portion between the flaps is increased, and the scraps are also increased to facilitate removal.

  It should be noted that, in the above-described die removal, the straight side portion 11 does not need to have a strictly straight center line of the amplitude of the waveform cutting edge 11a, and may be a curve that can be approximated to a straight line.

  Further, such a punching die can be applied not only to punching of corrugated cardboard sheets but also to punching of paperboard sheets and plastic sheets.

10 cutting member 10a tipped source unit 10b blade section 11 Chokuhen portion 11a waveform cutting edge 12 bend 12a non waveform cutting edge 20 substrate 21 Homizo _L 1, _{L 2} stretched length _r 1, _{r 2} radius of curvature

Claims (4)

A cutting blade member (10), which is a blade formed from a strip-shaped steel plate, and a substrate (20) in which the cutting blade member (10) is implanted,
Said knife member (10) is arranged in pairs, Chokuhen portion with a waveform cutting edge (11a) for punching the contour to form a continuous waveform having a predetermined pitch sheet straight linear (11), In the die -cutting of a sheet having a curved portion (12) having a non-corrugated cutting edge (12a) punching a sheet into a curved contour that does not form a continuous waveform, being continuous so as to be sandwiched between the two right side portions (11) ,
The two right side portions (11) respectively extend in the same direction so as to face each other via the curved portion (12), corresponding to both side edges of the groove portion formed in the sheet,
The curved portion (12) is formed in a semicircular arc shape so that both ends which are connection portions with the both right side portions (11) face in the same direction, corresponding to the valley bottom of the groove portion formed in the sheet. Die cutting of a sheet characterized by being bent . The cutting blade member (10) has a blade base (10a) that is press-fit into the engraved groove (21) of the substrate (20), and a blade that becomes thinner in a tapered shape from the blade base (10a) to the tip. And (10b),
Cutting die of sheet according to claim 1, wherein the waveform cutting edge (11a) and the non-waveform cutting edge (12a) is formed in said blade mounting portion (10b). The stretch length (L ₁ ) obtained by linearly extending one pitch of the wavy cutting edge (11a) is shorter than the stretching length (L ₂ ) obtained by linearly extending the curved non-corrugated cutting edge (12a). 3. The die for a sheet according to claim 1, wherein the corrugated cutting edge (11a) and the non-corrugated cutting edge (12a) are formed. The non-corrugated cutting edge (12a) in the curved portion (12) is curved with a radius of curvature (r ₂ ) larger than the radius of curvature (r ₁ ) at the top of the waveform of the corrugated cutting edge (11a) in the right side portion (11). The die for a sheet according to any one of claims 1 to 3 , wherein the sheet has a shaped shape.

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