JP5829656B2 - Plastic working method of metal plate - Google Patents

Description

  The present invention relates to a plastic working technique for a metal plate.

A conventional pressing method will be described with reference to FIG.
As shown in FIG. 5A, the press device 100 includes a lower mold 102 mounted on a base 101, a blank holder 103 disposed so as to surround the lower mold 102, and the blank holder 103 being moved up and down. It consists of rods 104, 104 and an upper mold 106 suspended from the elevating member 105.

First, the upper mold 106 is separated upward from the lower mold 102, and the blank material 107 is placed on the lower mold 102 and the blank holder 103.
Next, the upper die 106 is lowered by the elevating member 105. Then, as shown in FIG. 5A, the blank holder 103 presses the edge of the blank material 107 against the peripheral edge of the upper mold 106.

In the blank material 107 shown in FIG. 5B, the edge 108 indicated by oblique lines is restrained by the blank holder 103.
From this state, the upper mold 106 is further lowered in FIG.
Then, as shown in FIG. 5C, the blank material 107 is plastically processed by the lower mold 102 and the upper mold 106.

After the plastic working, the edge (unnecessary part) 108 is cut off.
If the area of the edge 108 is too small, the edge 108 may be detached from the blank holder 103. Therefore, although a certain size is required, the larger the area of the edge 108, the worse the yield.
A technique for reducing the area of the edge 108 has been proposed while improvement in yield is required (see, for example, Patent Document 1 (FIG. 1)).

Patent Document 1 will be described with reference to FIG.
FIG. 6 is a diagram for explaining the basic principle of the prior art. As shown in FIG. 6A, the blank 111 has a waveform in which the cutting line is a sine curve. The edge 112 of the blank material 111 is pressed by the blank holder.

If it is a form of FIG.6 (b), the length of the blank material 107 is L1.
If this is the form of FIG. 6A, the maximum length of the flank material 111 is L1, but the length on the yield is L2 smaller than L1. As a result, the yield of (a) increases.

By the way, when the blank material 107 or 111 is thrown into the press apparatus 100 shown in FIG. 5A, it is necessary to position the blank material 107 or 111.
As shown in FIG. 7A, the blanking material 111 is applied to the positioning stopper 113 for positioning. At this time, the sharpened tip 114 of the edge 112 hits the positioning stopper 113 (referred to as spotting), and the sharpened tip 114 is recessed as shown in FIG. As a result, the positioning accuracy is reduced, which affects the pressing process.

Conventional techniques capable of eliminating such problems have been proposed (see, for example, Patent Document 2 (FIG. 1)).
FIG. 8 is a diagram for explaining the basic principle of the improved conventional technique. The edge 116 of the blank 115 is formed in a rectangular sawtooth shape. The part that hits the positioning stopper 113 is a line. That is, the defect is solved because the point hit is corrected per line.

However, it has been found that another problem occurs in this improved conventional technique. This new problem will be described with reference to FIG.
As shown to Fig.9 (a), the edge 116 of the blank material 115 is obtained by cut | disconnecting using the cutting blade 117 with which a cutting machine is equipped.
After cutting, when the cutting blade 117 is moved to the front side of the drawing, the edge 116 is also bent to the front side of the drawing by friction. This bending is not preferable because it causes a harmful deformation of the edge 116.

As one countermeasure against bending, as shown in FIG. 9B, after cutting, the cutting blade 117 is moved horizontally away from the blank member 115 and then moved to the front side of the drawing. This prevents the edge 116 from flexing toward the front of the drawing.
However, when the cutting blade 117 is moved horizontally, the cutting blade 117 is in sliding contact with the sides 118 and 118 of the edge 116, so that fine chips are generated.
As a result, as shown in FIG. 9C, the chips adhere to the sides 118, 118 in the form of dust 119. There is a concern that this dust 119 will have an adverse effect in the next pressing step.

  Therefore, there is a demand for a manufacturing technique that does not generate dust when manufacturing a blank with a cutting blade.

Japanese Patent No. 2691143 JP 2004-160490 A

  An object of the present invention is to provide a manufacturing technique in which dust is not generated when a blank material is manufactured with a cutting blade.

The invention according to claim 1 is a cutting blade that cuts the strip so that the cutting line has a sawtooth shape, and the cutting blade is a first straight portion along a first line perpendicular to the longitudinal axis of the strip. And a substantially straight S-shaped line connecting the second straight line portion along the second line parallel to the first line and a predetermined distance away from the first line, and the ends of the first straight line portion and the second straight line portion. A metal plate plastic working method that uses a cutting blade that does not include a straight line in the curved portion, and is a blank material by cutting the strip into a predetermined length with the cutting blade A blanking process, a positioning process in which the straight portion of the edge of the blank material is applied to a positioning stopper of a press device to position the blank material, and the blank material is molded while pressing the serrated edge with a blank holder. Unnecessary parts are removed from the press product by the press process to obtain the press product and the trim device. Characterized by comprising the trim to obtain a product by dividing.

  In the invention according to claim 2, the curved portion is formed in a substantially S shape by continuously forming a quarter circumference and a quarter circumference divided into four, based on a circumference of a circle having a predetermined distance as a diameter. It is characterized by that.

In the invention which concerns on Claim 1, the side of a cutting blade is made into the substantially S-shaped curve part, and does not include the straight line.
Even if the cutting blade is moved horizontally after cutting, the side of the cutting blade does not slide on the edge of the blank material. As a result, there is no worry about the generation of garbage.
Moreover, in this invention, it consists of the cutting process implemented using the cutting blade of this invention, the process of positioning a blank material, the press process of plastically processing a blank material, and the trim process of excising an unnecessary part.
Since no dust is generated in the cutting process, good plastic working can be performed in the pressing process. As a result, a product with good quality is provided.

  In the invention which concerns on Claim 2, a curve part makes a 1/4 circle and a 1/4 circle continuous, and makes it a substantially S shape. The shape of the curved portion is uniquely determined, and the design of the cutting blade becomes easy.

It is sectional drawing of the cutting blade which concerns on this invention. FIG. 2 is an enlarged view of part 2 of FIG. 1. It is a flowchart explaining the plastic working method of the metal plate which concerns on this invention. It is a figure explaining a cutting process. It is a figure explaining the conventional press work method. It is a top view of the blank material which has a sine curve-shaped edge. It is a figure explaining the problem in the edge of a sine curve shape. It is a top view of the blank material which has a rectangular serrated edge. It is a figure explaining the problem in a rectangular serrated edge.

  Embodiments of the present invention will be described below with reference to the accompanying drawings.

  As shown in FIG. 1, the cutting machine 10 includes a die 11 and a cutting blade 20 called a punch as main parts. In order to facilitate understanding, the cutting blade 20 is shown separated from the die 11 in the horizontal direction, but the cutting blade 20 is used in a substantially overlapping form with the die 11 in plan view.

The cutting blade 20 is parallel to the first straight line portion 22 along the first line 21 orthogonal to the longitudinal axis (FIG. 3, reference numeral 31 a) of the strip (FIG. 3, reference numeral 31) and the first line 21. The second straight line portion 24 along the second line 23 that is separated from the first line 21 by a predetermined distance D, and the substantially straight S-shape that connects the ends of the first straight line portion 22 and the second straight line portion 24 to each other. And a curved portion 25.
As a result, the curved line portion 25 does not include a straight line.

The curved portion 25 connects two arcs, and the radius R1 of one arc and the radius R2 of the other arc may be the same or different.
An example in which the radius R1 and the radius R2 are the same R will be described with reference to FIG.

FIG. 2 is an enlarged view of part 2 of FIG. 1 and is based on the circumference of a circle 27 that draws a predetermined distance D as a diameter, as shown in FIG.
The circumference of the circle 27 is divided into four quarters (a quarter circumference connecting the points P1 and P2) and a quarter circumference (a quarter circumference connecting the points P2 and P3). The curved portion 25 is formed in a substantially S shape. One end of the curved portion 25 is connected to the first straight portion 22, and the other end of the curved portion 25 is connected to the second straight portion 24.

A plastic working method for a metal plate performed using the cutting blade 20 described above will be described with reference to FIG.
As shown to Fig.3 (a), the strip 31 which consists of a thin metal plate is prepared, and this strip 31 is cut | disconnected with the cutting machine 10 shown in FIG. 1 (cutting process).

This cutting process will be described in detail with reference to FIG.
FIG. 4A shows a form immediately after cutting, and the cutting blade 20 is moved from the front side of the drawing to the back of the drawing with respect to the blank material 32.
Next, as shown in FIG. 4B, the cutting blade 20 is moved in the horizontal direction and away from the blank material 32. At the time of this horizontal movement, the side surfaces of the cutting blade 20 are curved portions 25, 25, and leave without sliding against the edge 33 of the blank material 32. Therefore, no garbage is generated.

  As a result, as shown in FIG. 3B, a blank material 32 having a sawtooth cut line is obtained. This blank material 32 is put into a press device. At the time of insertion, the linear portion 34 at the tip hits the positioning stopper (FIG. 7A, reference numeral 113). Since it is so-called per line, there is no fear that the edge 33 of the blank 32 is depressed, and the positioning accuracy is kept good (positioning step).

While pressing the serrated edge 33 with the blank holder, the blank member 32 is subjected to plastic working by a press device. As a result, a pressed product 36 shown in FIG. 3C is obtained (pressing process).
The peripheral portion of the press product 36 becomes an unnecessary portion 37. The unnecessary portion 37 is cut out by a trim device (trim process).
As a result, the product 38 shown in FIG. 3D can be obtained. The product 38 is preferably a side panel, a bonnet, or a roof of a vehicle body that requires strict finishing accuracy.

  In addition, although this invention is suitable for the press work of a vehicle body, it may be applied to the press work in general products other than a vehicle body.

  The present invention is suitable for press working of a vehicle body.

  DESCRIPTION OF SYMBOLS 10 ... Cutting machine, 20 ... Cutting blade, 21 ... 1st line, 22 ... 1st straight part, 23 ... 2nd line, 24 ... 2nd straight part, 25 ... Curved part, 31 ... Strip, 31a ... Longitudinal axis of the strip, 32 ... blank material, 33 ... edge of the blank material, 34 ... straight line portion of the edge, 36 ... pressed product, 37 ... unnecessary portion, 38 ... product, 100 ... pressing device, 103 ... blank holder, 113 ... Positioning stopper, D ... Predetermined distance and diameter of basic circle.

Claims (2)

A cutting blade for cutting the strip so that the cutting line is serrated ,
The cutting blade includes a first linear portion along a first line orthogonal to the longitudinal axis of the strip, and a second line that is parallel to the first line and separated from the first line by a predetermined distance. And a substantially S-shaped curved portion connecting ends of the first straight portion and the second straight portion, and a cutting blade that does not include a straight line is used for the curved portion. A metal plate plastic working method,
With the cutting blade, a cutting step of obtaining a blank material by cutting the strip to a predetermined length;
A positioning step of positioning the blank material by applying a linear portion of the edge of the blank material to a positioning stopper of a press device;
A pressing step of obtaining a press product by molding the blank material while pressing a serrated edge with a blank holder;
In the trim device, a trim step for obtaining a product by cutting an unnecessary part from the pressed product,
A plastic working method for a metal plate. The curved portion of the cutting blade is based on the circumference of a circle drawn with the predetermined distance as a diameter, and is formed into a substantially S shape by continuously dividing a quarter circumference and a quarter circumference. The method for plastic working a metal plate according to claim 1, wherein:

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