JPS58209520A - Punching method of plastic sheet - Google Patents

Abstract

PURPOSE:To obtain well finished blanks from a plastic sheet automatically in a high speed by a method wherein cutting lines are provided on the plastics sheet in accordance with the configuration of the blanks so as to remain a plurality of connecting parts having minute widths as well as the lower part thereof as a non-cutting part. CONSTITUTION:The cutting lines 7 are punched in accordance with the configurations of the blanks in the plastics sheet 5 so as to remain a plurality of connecting parts 6 having the width less than 50mum, preferably 10-20mum and the non-cutting parts on the lower side of the plastics sheet 5. Subsequently, unnecessary parts are separated from the plastics sheet 7 provided with the cutting lines 7 normally. EFFECT:The plastics sheet will never be in disorder in a punching machine. The unnecessary parts may be separated easily and cleanly.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for punching out a plastic sheet 1 for punching blanks for manufacturing plastic cases.

Currently, video cassette cases, etc. are made by punching plastic sheets such as polypropylene sheets into a predetermined shape.
They were manufactured by making creases, assembling them, and sealing the joints using an impulse sealer.

When punching out glass sheets, the finished state of the cut surface depends on the state of the cutting die, and in order to improve this finished state, conventionally the pressure of the cutting die has been adjusted during cutting.

On the other hand, there are several types of punching machines, ranging from manual ones to high-speed automatic ones, and in order to mass produce it, it was absolutely necessary to use an automatic one.

However, when a high-speed automatic punching machine is used to punch out a glass sheet using the conventional method, the cutting condition is too good, and when the unnecessary part is cut off on the - side, the punched plastic sheet moves unexpectedly in the cutting machine. As a result, the glass sheet became disorganized and the cutting machine often stopped.

Conventionally, paperboard f1. ), as shown in Figure 1, without cutting the predetermined shape in a continuous state, punch out the connecting parts (2) in the width range of 05 to 10 in several places for one shape.
A cutting line (3) was provided which cut the paperboard completely through the thickness.

A large number of paperboards provided with this cutting line (3) were then grouped together to separate blanks from unnecessary parts.

In the case of plastic sheets, if you make cuts in the same way as with paperboard, it may be difficult to separate them, or the blanks may move in the punching machine (-1 Blanks with a very good finish can be produced at high speed) It was difficult.

The present invention is a plastic sheet punching method that eliminates such deficiencies and punches out blanks with a good finish from a plastic sheet at high speed.The present invention will be described below with reference to the drawings.

As shown in FIG.
1. Depending on the shape of the blank, cut the cutting line (
7) is provided according to the shape of the blank 1, and this cutting line (7) is placed on the plastic sheet (7) as shown in Figure 3.
5), but leave an uncut portion (8) of 4 to 6 μm.

And the plasti-tsuk set up in this condition/) [
A large number of sheets of paperboard are stacked and separated using a device that separates unnecessary parts, which is used in conventional paperboard.

According to the present invention, when punching a plastic sheet in this way,
The cutting part (above, the whole thickness is not punched, the cutting line is provided leaving an uncut part of 4 to 6 tt, and the connecting part of 50μ or more, preferably 10 to 20μ is provided and punched. The plastic sheet does not become cluttered in the punching machine, and the punching process can be performed automatically using a high-speed F board.

Moreover, the unneeded parts of the punched out Silastic Note could be easily and neatly separated in the same way as with paperboard, using a device that separates unnecessary parts conventionally used in temporary assembly.

[Brief explanation of drawings]

Figure 1 is a plan view showing the cutting lines of the paperboard, Figure 2 is a plan view showing the cutting lines of the plastic sheet, and Figure 6 is a plan view showing the cutting lines of the plastic sheet.
FIG. 2 A A', σ) is a sectional view. (1))...Plastic sheet (6)...Connection part
(7)...Cut R line (8)...Uncut part

Claims (3)

[Claims] (1) A method for punching out a plastic sheet, which is characterized in that a plurality of connection parts each having a width of 50 μm or less are left in the plastic sheet according to the shape of the blank, and a cutting line is provided by leaving an uncut part at the bottom of the plastic sheet. (2) The method for punching out plastic notebooks according to claim 1, wherein the width of the connecting portion is in the range of 10 to 20 μm. (3) The method for punching a glass sheet according to claim 1 or 2, wherein the thickness of the uncut portion is in the range of 4 to 6 μm.