JPH0123621Y2 - - Google Patents

Description

[Detailed Description of the Invention] Industrial Application Field This invention relates to a press die for shearing a panel-shaped workpiece, particularly for trimming the peripheral edge of a panel-shaped workpiece.

BACKGROUND TECHNOLOGY As is well known, most of the body panels of automobiles are formed by drawing, but as shown in Fig. 4A and B, the peripheral edge of the panel P has wrinkles from the drawing process. remains in the shape of a flange as a non-product portion S, and therefore this non-product portion S needs to be trimmed in a subsequent process.

FIG. 5 shows a typical conventional mold structure that controls the above-mentioned trimming process, in which a predetermined panel-shaped workpiece W is placed on the punch 1 and the upper holder 2 is lowered. This upper holder 2 has a sexual die 3
is fixed, and a pad 5 is elastically supported via an elastic body 4. Therefore, after the pad 5 comes into contact with the panel-shaped workpiece W and clamps it under pressure, the upper holder 2 further descends. As shown in FIG. 6, the peripheral edge of the panel-shaped workpiece W is trimmed by the shearing action of the punch 1 and the sectional die 3.

In addition, 6 indicates a lower holder, 7 indicates a pad retainer that restricts the stroke of the pad 5 with respect to the upper holder 2, and S indicates a scrap (non-product part) generated by the trimming process.

Problems to be Solved by the Invention In such a conventional press die for trimming, due to the special nature of shearing, the cutting edge 1a on the punch side and the cutting edge 3a on the sectional die side are separated as shown in Fig. 6. Since it is necessary to secure a predetermined clearance C between the panel-shaped workpiece W and the panel-shaped workpiece W, burrs F are likely to occur on the sheared end surface of the panel-shaped workpiece W (FIG. 7). Moreover, the above clearance C is subtly affected by the wear of the cutting edges 1a and 3a due to repeated machining, the clearance of the guide mechanism between the upper and lower dies (not shown), etc., so it is impossible to completely prevent the occurrence of burrs. It is extremely difficult.

On the other hand, especially in the case of car body panels, painting is performed after press working, but if burrs like the ones mentioned above remain, the burrs themselves have acute angles, making it difficult for the paint film to adhere to them and causing rust. It is necessary to remove the burr in some way.

Conventionally, therefore, clearance management has been carried out by periodically checking the occurrence of burrs and performing mold maintenance work in the direction of narrowing the above-mentioned clearance. However, in order to prevent interference between the cutting blades, the clearance cannot be kept below the guide clearance between the upper and lower dies as described above, so there is a limit to how narrow the clearance can be.

Therefore, it is difficult to stably maintain a state in which no burrs are generated, so it cannot be an effective measure for preventing burrs, and it is necessary to carry out deburring work manually in the subsequent process.

The present invention is intended to provide a press die that allows the occurrence of burrs due to the various factors mentioned above and can remove the burrs at the same time as the trimming process is completed.

Means for Solving the Problems In the present invention, a convex sectional punch portion is provided near the cutting blade on the sectional die side, which comes into contact with the panel-shaped workpiece after the shearing action between the punch and the sectional die is completed. On the other hand, a punch-receiving recess is provided near the cutting edge on the punch side, which bends the end portion of the panel-shaped workpiece in cooperation with the sectional punch portion and draws the sheared end face away from the cutting edge of the sectional die. The structure is as follows.

Effects According to this configuration, even if burrs occur at the end of the workpiece, the end of the workpiece is slightly pulled in a direction away from the cutting edge of the sectional die almost immediately after the shearing action is completed, so the edge of the sheared end face The burr is easily removed by slidingly contacting the wall surface of the punch receiving recess.

Embodiment FIG. 1 is a diagram showing a more specific embodiment of the present invention, in which a convex block-shaped sectional punch 11 is fixed inside the cutting blade 10a of the sectional die 10 and adjacent to the cutting blade 10a. On the other hand, a punch receiving recess 12 corresponding to the sectional punch 11 is formed in a portion of the face surface 1b of the punch 1 adjacent to the cutting edge 1a. and,
A stroke difference of l is provided between the tip of the sectional die 10 and the tip of the sectional punch 11, and the sectional punch 11 is shaped into a panel almost at the same time or slightly later than the completion of the shearing action between the punch 11 and the sectional die 10. It is set so as to be in contact with the workpiece W.

According to this configuration, as shown in FIG. 5, when the upper holder 2 descends, the punch 1 and the pad 5 press and hold the panel-shaped work W. Then, as shown in FIG. 2A, the upper holder 2 further descends, and the punch 1 and the sectional die 10
The non-product portion (scrap) S at the end of the panel-shaped workpiece W is trimmed by the shearing action of the panel-shaped workpiece W.

At this time, the sectional punch 11 comes into contact with the product part of the panel-shaped work W almost at the same time as trimming is completed, or slightly later than this, and as shown in FIG. Bend the end portion of the workpiece W into a substantially dogleg shape. As a result, the end portion of the panel-shaped workpiece W is bent by the amount that the cutting edge 1 of the sectional die 10 is bent.
Since it is pulled in the direction away from 0a and the edge portion of the sheared end surface e comes into sliding contact with the wall surface of the punch receiving recess 12, the burr F generated during the previous trimming is cut off.

Thereafter, the sectional die 10 reaches the bottom dead center and rises again, causing the burr F to fall under its own weight.

Here, the end of the panel-like workpiece W that has been trimmed remains bent into a dogleg shape, but if flange bending is to be performed in a later process, for example, as shown in FIGS. 3A and 3B. As shown, since the flange bending punch 13 and the sectional die 14 are used to clamp and straighten the flange, there is no problem in terms of product quality.

Effects of the invention As described above, according to the invention, even if burrs are generated during trimming, they are separated immediately after trimming, so there is no need for deburring in the post-process, and there is no direct rusting. It is not a cause of occurrence.

Furthermore, whereas in the past it was necessary to strictly manage the clearance to narrow it as much as possible, this invention removes burrs once generated, so clearance management is not as strict as before. The number of man-hours required for mold maintenance work and other clearance management can be reduced.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of essential parts showing an embodiment of the present invention;
Figures 2A and B are explanatory diagrams showing the operating state of Figure 1, Figures 3A and B are process illustrations of flange bending after trimming, and Figures 4A and B are examples of panel-shaped workpieces. An explanatory diagram showing an automobile body panel, Fig. 5 is a sectional view of a typical conventional trimming press mold, Fig. 6 is an enlarged view of the main part of Fig. 5, and Fig. 7 is a main part of a panel workpiece. It is an enlarged view. 1... Punch, 1a... Cutting blade, 5... Padded,
10...Sectional die, 10a...Cutting blade, 1
1...Sectional punch, 12...Punch receiving recess, W...Panel workpiece, F...Burr, e...
...Sheared end surface.

Claims (1)

[Scope of utility model registration request] A trimming press type in which a predetermined panel-shaped workpiece is pressurized and clamped between a punch and a pad, and then the panel-shaped workpiece is sheared by the shearing action of the punch and a sectional die that descends with the pad and is movable relative to the pad. , a convex sectional punch portion is provided near the blade portion of the sectional die, and the convex sectional punch portion comes into contact with the panel-shaped work later than the shearing action between the sectional die and the punch, while the sectional punch portion is provided near the cutting edge of the punch. A trimming press mold characterized by forming a punch-receiving recess that bends an end portion of a panel-like workpiece in cooperation with a punch receiving recess that pulls the end portion away from a cutting edge of a sectional die.