JPH0871996A - Method and device for punching plastic sheet - Google Patents

Abstract

PURPOSE: To provide a single punching process in which an external shape can be punched out by a single step, and a punch-off fragment can be automatically removed after punching and rule-lining steps are carried out, and which is therefore suitable for mass production with a less number of steps, is highly efficient. CONSTITUTION: In a process of forming an developed sheet 2 out of a long plastic sheet, the plastic sheet P is set on a planer panel 3, and a Tomson die incorporating cutting blades 4a, 4a, and a rule-lining cutting blade 4b is driven into the plastic sheet so as to simultaneously carry out punching of an external shape of the developed sheet P, punching of a hook hole 2 and rule-lining. In this case, the hook hole 2a is prevented from being completely punched out, and an uncut part is left in a part of the outer periphery thereof. Then, the developed sheet 2 is set on a lower panel 5, and a cut-in piece 21 thereof is clamped by a folding jig 6 and opposite pawl parts 7a, 7b while the developed sheet 2 is moved up and down so that cut-in piece 21 is separated. Thereafter, the cut-in piece 21 is clamped by a clamping jig 7, and accordingly, it can be removed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention efficiently punches a plastic sheet into a required die by forming a through-hole having a required shape, and efficiently disperses the dregs of the hole on the processing surface. The present invention relates to a construction method and a device that can be removed.

[0002]

2. Description of the Related Art A simple assembly box obtained by punching a plastic sheet into a required expansion die and bending each piece of the expansion die appropriately is used as a package for transporting and displaying articles. There is.

Conventionally, when a through hole such as a hook hole for suspending is provided in this assembly box, a cutting blade and a ruled line blade are incorporated in a Thomson type (a punching die for punching only with a cutting blade) in order to reduce the working process. The Thomson mold was driven from the upper surface of a plastic sheet placed on a flat plate, and the outer shape was punched, the hole was punched, and the ruled line was processed at the same time in one stroke.

In this case, if the outer periphery of the through hole is completely punched out, the leftover dust remains on the flat plate, and when the next plastic sheet is punched out, the sheet surface may be scratched or uneven. Therefore, in the above-described hole punching, a cutout is provided in a part of the outer periphery of the through hole, and the scraps are manually removed in the subsequent process.

[0005]

SUMMARY OF THE INVENTION The above-mentioned conventional methods are inferior in productivity because they have to rely on humans to remove scraps. Also, if you punch out only the through holes using a set of punches and dies, you can easily make holes without leaving any scraps on the machined surface. Therefore, there is a problem that the processing cost becomes high.

The present invention has been made in view of the above problems of the prior art, and an object of the present invention is to automatically and surely remove a dreg of a through hole after punching a plastic sheet. Another object of the present invention is to provide a plastic sheet punching method and device which can be removed efficiently and are suitable for mass production.

[0007]

In order to solve the above problems, a method for punching a plastic sheet according to the present invention is such that a plastic sheet is punched into a sheet of a desired mold using a cutting blade, and at the same time, a desired shape is formed in the sheet. A step of providing a cut piece, a step of bending the cut piece to the front surface side or the back surface side of the sheet, and a step of sandwiching the bent cut piece with a jig and moving the jig to separate it from the sheet. It is characterized by having.

Further, the punching device for a plastic sheet of the present invention includes a first process unit having a Thomson type in which a cutting blade is incorporated, and a lower plate on which the plastic sheet processed by the first process unit is placed. And a second process unit having a bending jig for bending the piece cut by the cutting blade and a holding jig for holding the piece.

[0009]

[Operation] By holding the cut piece with a jig,
The cut piece can be reliably separated from the sheet. The separated cut pieces fall below the jig when the clamped state of the jig is released, and do not remain on the processed surface.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A preferred embodiment of the present invention will be described below with reference to the drawings. In order to form a plastic assembly box 1 as shown in FIG. 1 (A), the present invention cuts a plastic sheet as a development sheet 2 as shown in FIG. 1 (B), and in particular, hooks in the development sheet 2. It can be applied when it is necessary to form a through hole such as the hole 2a.

FIG. 2 shows the processing steps of the present invention from the long plastic sheet to the formation of the expansion sheet 2. In this processing step, first, the long plastic sheet P is set on the flat plate 3 in the first step, and the cutting blade 4
Thomson type 4 incorporating a, 4a and ruled blade 4b
Are punched from the upper surface of the plastic sheet P, and the outer shape of the expansion sheet 2, the hook holes 2a, and the ruled line are processed at the same time.

In the first step, the hook hole 2a is not completely punched out, and as shown in FIG. 3, a part of the outer circumference is left uncut so as not to be separated from the expansion sheet 2. Then, the groove 2c is simultaneously formed at an appropriate depth in the uncut portion so that the cut piece 21 can be easily separated from the unfolding sheet 2 when the cut piece 21 is pulled.

The shape and size of the cut piece 21 and the groove 2c
The depth of can be appropriately set by the cutting blade 4a, but practically, for example, when a through hole having a diameter of 8 mm is bored in the expansion sheet 2 having a thickness of 1 mm, of
A length of about 2 mm may be left uncut, and a groove having a depth of about 0.7 mm may be formed in this portion.

Further, since the development sheet 2 is difficult to convey to the next step if it is completely punched out, it is left in the plastic sheet P and separated in the third step described later.

Next, in the second step, the spread sheet 2 is set on the lower plate 5 having a hole 5a slightly larger than the hook hole 2a, and the bending jig 6 and the clamping jig 7 are used to carry out the above-mentioned process. The cut piece 21 is removed from the development sheet 2.

The bending jig 6 comprises a rod body 6a having a diameter smaller than that of the hook hole 2a and an air cylinder (not shown) for reciprocating the rod body 6a. The rod body 6a extends from above the hole 5a. It is arranged so that it can move back and forth.

The holding jig 7 supports a claw portion 7a which is reciprocally movable in the horizontal direction by an air cylinder 7c, supports the air cylinder 7c and the claw portion 7a from below, and has an end portion meshing with the claw portion 7a. Claws 7 that can be provided
b and an air cylinder 7d that reciprocates the claw portion 7b in the vertical direction, and is arranged below the hole 5a.

The processing procedure of the second step will be described with reference to FIG. 4. First, in step A, the spread sheet 2 is set on the lower plate 5. At this time, the hook hole 2a and the hole 5a are set so as to overlap with each other, and the rod body 6a is placed above the hook hole 2a so that the claw portion 7
The a and 7b are located below the hole 5a with a space between both parts.

Next, in step B, the rod 6a is moved downward until the tip enters the hole 5a, and the cut piece 21 is bent downward. At this time, the claws 7a and 7b are moved upward.

Then, in step C, the claw portion 7a is horizontally moved to the right in the drawing to sandwich the cut piece 21 between the claw portions 7a and 7b, and in the step D, both claw portions 7a and 7b are moved downward as they are. Then, the cut piece 21 can be separated from the expansion sheet 2. In this case, since the hole 5a of the lower plate 5 is formed larger than the hook hole 2a, the sheet 2 is not pulled downward and bent.

The cut-out pieces 21 separated from each other include two claw portions 7a,
If the clamping state is released by opening the interval of 7b, the clamping jig 7
Since it falls below, if a storage box or the like is provided at a predetermined position, it can be collected without being scattered around. In addition, the rod body 6a should be prepared for the processing of the next sheet after the claws 7a and 7b sandwich the cut piece 21 and the claws 7a and 7b separate the cut piece 21 from the development sheet 2. , Move it to its original position.

Finally, in the third step, the development sheet 2 is separated from the plastic sheet P to complete the entire punching step of the plastic sheet.

In this embodiment, the cut piece 21 is bent and removed below the expansion sheet 2, that is, on the back surface side, but it may be bent and removed above the expansion sheet 2, that is, on the front surface side. . Further, the shape or structure of the jig or the like used in the above-mentioned processing step is not limited to the aspect of the present example, and may be appropriately selected. For example, instead of the air cylinder, another driving mechanism such as a solenoid may be operated.

[0024]

As described above, according to the construction method and apparatus of the present invention,
After performing outline punching, hole punching and ruled line processing at the same time in one punching process, it is possible to automatically and reliably remove the punched dust from the hole, so the punched dust remains on the processed surface and scratches the sheet surface. There is no fear, and by using the construction method and apparatus of the present invention, it is possible to realize an efficient processing process corresponding to mass productivity with less steps without manpower.

[Brief description of drawings]

FIG. 1A is a perspective view of an example plastic assembly box to which the present invention can be applied, and FIG. 1B is a development view of this box.

FIG. 2 is a diagram showing a processing step of the present invention from forming an elongated plastic sheet to forming a spread sheet.

FIG. 3A is a plan view of a cut piece provided by a punching method of the present invention, and FIG. 3B is a sectional view thereof.

FIG. 4 is a diagram showing a step of separating the cut piece from the spread sheet.

[Explanation of symbols]

 1 Assembly box 2 Unfolding sheet 2a Hook hole 3 Flat plate 4 Thomson type 5 Lower plate 6 Bending jig 7 Clamping jig 21 Cut piece P Plastic sheet

Claims (2)

[Claims] 1. A step of punching a plastic sheet into a sheet of a desired shape by using a cutting blade and at the same time providing a cut piece of a required shape in the sheet, and a step of bending the cut piece to one side of the sheet, A punching method for a plastic sheet, which comprises a step of sandwiching the bent cut piece with a jig and moving the jig to separate it from the sheet. 2. A first process device section having a Thomson type in which a cutting blade is incorporated, a lower plate on which a plastic sheet processed by the first process device section is placed, and a piece cut by the cutting blade. A punching device for a plastic sheet, which comprises at least a second process device section having a bending jig for bending a piece and a holding jig for holding the piece.