JPS61209732A - Pressing method - Google Patents

Abstract

PURPOSE:To make an blank stock falling in the course of starting a forming stage from a push-back stage by providing respectively a die on the upper part of the material to be worked of a metallic plate, etc. and a punch on the lower part and by extruding the blank stock to the upper part, striking the punch from the lower part. CONSTITUTION:A circular blank 5 is produced with the part hit by a punch 4 being pushed up to the upper part and the other becomes a strip stock 6 when the punch 4 is struck to a metallic plate 1a by driving up from the lower part in the state of arranging a cylindrical die 3 on the upper part of the metal lic plate 1a and the punch 4 on the lower part. A notch 12 is formed between the blank 5 and strip 6 when a push-back stage is performed by placing the metallic plate 1a having the blank 5 thus produced on the upper face of a ramming board 8 and by driving a ramming press 7 down from the upper part but the blank 5 is not removed from the strip 6 by this notch 12 in the course of the blank 5 being moved to the forming stage.

Description

DETAILED DESCRIPTION OF THE INVENTION Object of the Invention (Field of Industrial Application) The present invention relates to a press processing method for manufacturing a press product of a predetermined shape from a workpiece.

(Conventional technology) Conventionally, the lancing process and push process have been used to obtain products of a predetermined shape and size from metal plates by press working.
A method using a back process is known.

The method will be explained as follows, taking as an example the case where a metal plate 21 shown in FIG. 6 is punched out to produce an eave-shaped product 22 as shown in FIG. 7.

First, as shown in FIG. 8, the metal plate 21 is placed on the upper surface of the cylindrical die 23, and the punch 24 is lowered from above, and the punch 24 is placed on the metal plate 21 as shown in FIG. Make it about 172mm thick.

Then, the part of the metal plate 21 that was hit by the punch 24 is
The blank material 25 protrudes downward from the part that did not hit.
is formed (lancing process).

In addition, the part where the punch 24 did not hit is covered with the strip material 2.
It is called 6.

Next, as shown in FIG. 10, after applying the punching board 28 to the upper surface of the metal plate 21, the punching press 27 is launched from below the metal plate 21 to punch the blank material 25. Then, the blank material 25 returns to its original position within the metal plate 21 (a position on the same surface as the strip material 26), and a cut 32 is formed between the blank material 25 and the strip material 26 (push-back process). .

Next, as shown in FIG. 11, the pushed back metal plate 21 is placed on the upper surface of the cylindrical bending die 29, and the bending punch 30 is inserted into the blank 25 from above the metal plate 21.
The peripheral edge of the blank material 25 is bent (forming process).

Then, the product 22 held by the pad portion 31 in the die 29 is taken out, and the remaining strip material 26 is taken out from between the bending die 29 and the bending punch 30.

(Problems to be Solved by the Invention) Although the above method has a corresponding effect, the metal plate 21 that has been pushed back from the push back process
During the process of transferring the blank material to the molding process, the blank material 25 sometimes fell off the strip material 26, as shown in FIG. Furthermore, even if it did not come off completely, it sometimes came off partially as shown in FIG.

If the metal plate 21 from which a part of the blank material 25 has been removed is directly transferred to the molding process and molded, the blank material 25 will cause defects in the molding process.

Therefore, in the prior art described above, this cause must be eliminated.

The inventor of the present invention investigated the cause of this problem and found that the reason why the blank material 25 comes off from the strip material 26 is due to the direction of the tip of the notch 32.

That is, the cut 32 tends to be formed such that its tip deviates toward the blank material 26 as shown in FIG. 14. If the cut 32 becomes deeper due to some action, the side surface of the blank material 25 will expand downward like a trumpet, and the blank 25 will lose its grip on the strip material 26 and come off from it. be.

Therefore, an object of the present invention is to provide a press working method that uses a lancing process and a push-back process in which the blank material 25 does not fall off the strip material 26.

Structure of the Invention (Means for Solving Problems) This invention provides a die above a workpiece such as a metal plate and a punch below the workpiece, and inserts the punch into the workpiece from below. There is a lancing process in which the blank is pushed upwards by striking it against the workpiece, followed by a lancing process in which the blank pushed upward is pushed back to its original position within the workpiece.
The above-mentioned problems are attempted to be solved by employing a press working method that includes a back process.

(Function) Since the blank material is pushed upward in the lancing process, the cut formed between the blank material and the strip material obtained after passing through the push-back process is shaped like a trumpet toward the strip material as it goes upward. It is expanded and formed.

(Example) An example in which the present invention is embodied in a method of manufacturing a dish-shaped product by selecting a metal plate as a workpiece will be described with reference to FIGS. 1 to 5.

[Lancing Step] As shown in FIG. 1, a punch 4 is installed below a cylindrical die 3. At this time, the dimensions are set so that a clearance C is created between the inner circumferential surface of the die 3 and the outer circumferential surface of the punch 4.

Then, the metal plate 1a carried by the conveyor is inserted between the die 3 and the punch 4 and set so as to be in contact with the lower surface of the die 3.

Next, the punch 4 is launched from below toward the bottom surface of the die 3 and hits the metal plate 1a. Then, as shown in FIG. 2, the portion of the metal plate 1a hit by the punch 4 is pushed upward, forming a circular blank material 5, and the other portion becomes a strip material 6.

At this time, the pressing amount is 172 to 1/ of the thickness of the metal plate 1a.
It should be about 3.

[Push-back process] Next, the metal plate 1a having the blank material 5 made in the lancing process is transferred to a push-back process, and is brought into contact with the upper surface of the body punching board 8 as shown in FIG.

Next, the punching press 7 is lowered from above to punch the metal plate 1a, and the blank material 5 is pushed back to its original position.

Then, a cut 12 is formed between the blank material 5 and the strip material 6 as shown in FIG.
It extends to the side.

Therefore, even if the cut 12 becomes deeper as shown by the broken line in FIG. 4 due to some action, the peripheral edge of the blank material 5 may catch on the strip material 26 and fall off the strip material 6 and fall downward, or a portion of the blank material 5 may fall downward. It will never come off.

[Forming process] The metal plate 1a having the cuts 12 obtained in the push-back process is transferred to a forming process.

Then, as shown in FIG. 5, the metal plate 1a that has been subjected to the forming process is applied to the lower surface of the bending die 9, and the bending punch 10 is applied to the blank material 5 from below. Then, the blank material 5 is bent into the product 2 by the bending die 9, the pad portion 31 provided in the die 9, and the bending punch 10.

Then, the strip material 6 is bent using a bending die 9 and a bending punch 1.
If it is taken out from between 0 and 0, the machining of this step is completed.

As described above, according to the present invention, in the lancing process and the push-back process, the cut 12 is made in the metal plate 1a so that the side surface of the blank material 5 has a trumpet shape that spreads upward.
is formed, so that the blank material 5 does not come off from the strip material 6 during the process of moving the metal plate 1a to the forming process.

Note that the present invention is not limited to the above-mentioned embodiments, and can also be implemented in the following embodiments, for example.

(1) In the push-back process, it is also possible to reverse the vertical positions of the body punching board 8 and the body punching press 7 from those in the previous embodiment.

(2) In the molding process, as in the conventional process,
If it is possible to accurately determine the position of the bending punch 10 against the blank material 5, it is also possible to provide the bending punch 10 above the bending die 9, contrary to the case of the above embodiment.

(3) Workpiece materials 1 include aluminum, iron, silver, brass, nickel silver, cupronickel, and other various metal materials and fiber-reinforced metals;
Not only materials made of metallic composite materials such as dispersion-strengthened metals, but also semi-finished products obtained by appropriately pressing these materials or undergoing other processing can be used.

(4) The size and shape of the product 2 are not particularly limited as long as the product can be press-formed using a lancing process and a push-back process.

(5) Supplying the workpiece 1 to the lancing process,
From the same process to the push-back process, and then to the push-back process.
A roll feed device or other conveying means is used to move the workpiece 1 from the backing process to the forming process.

Effects of the Invention In the method of the present invention, the vertical positions of the punch and die provided in the lancing process are completely reversed from those of the conventional method, so that the blank material is pushed upward, so that the blank material and the strip material are separated after the push-back process. The incision made between the two is formed so as to widen upward.

As a result, the blank material does not pass through the strip material and fall from the strip material during the process of moving the workpiece material from the push-back process to the forming process.

Therefore, processing defects will not occur during the molding process.

[Brief explanation of drawings]

Figures 1 to 5 are drawings for explaining the method of the present invention, in which Figure 1 is a partial vertical cross-sectional view showing the positional relationship between the die and punch, and Figure 2 is a partial vertical cross-sectional view showing the lancing process. , Figure 3 is a partial vertical cross-sectional view showing the push-back process, Figure 4 is a partial longitudinal sectional view showing the push-back process.
The figure is an enlarged view of the X section in FIG. 3, and FIG. 5 is a partial vertical sectional view showing the molding process.

Claims (1)

[Claims] The die (3) is placed above the workpiece (1), and the die (3) is placed above the workpiece (1).
) are provided below the punches (4), respectively.
) is hit against the workpiece (1) from below to push the blank (5) upward, and then the blank (5) pushed upward is
) A press processing method that includes a push-back process to push it back to its original position within ).