JP2671182B2 - Punching method for plate - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for punching and molding a plate-like body which is used in a manufacturing process of a metal housing for housing electronic equipment.

[0002]

2. Description of the Related Art As a typical method of manufacturing a metal housing for housing electronic equipment, a large metal plate is formed into a plate having a predetermined shape by using an automatic punching and forming machine under numerical control called a punch press or the like. There is a method of punching a shape, bending necessary sides to form a three-dimensional shape, and spot welding the overlapping portion.

Usually, before or after the above-mentioned punching-molding step, another processing step of forming through holes or screw holes of a predetermined shape at predetermined positions on the plate-shaped body is added, so that the punched plate-shaped body is entirely processed. It is necessary to keep connection with the original plate until the processing process is completed. For this reason, punching is performed while leaving an appropriate number of thin joints for temporary fixing called joints between the original plate and the plate-like body by breaking each joint after the completion of all processing steps. The method of separating from the original plate is adopted. If the strength (dimension) of each connecting part is too small, the connecting part will break during the other processing steps after punching, causing separation from the original plate. Conversely, if it is too large, the breaking work at the time of separation will be difficult. , Set to an appropriate size.

Conventionally, the shape of each of the connecting portions is as shown in FIG.
A beam shape having a uniform width is adopted as illustrated in FIG. In FIG. 5, 50 is an original plate, 51 and 52 are plate-shaped members punched and formed from these original plates, and 53a to 53d are four connecting portions for temporarily fixing the original plate 50 and the plate-shaped member 51.
The punched plate-like body 51 shows a state before being separated from the original plate 50, and the punching-molded plate-like body 52 shows a state after separating from the original plate 50 by breaking the connecting portion. As shown, the plate-like body 52 separated from the original plate
A protrusion formed by the destruction of the connecting portion remains in the. The plate-shaped body after this separation is subjected to the step of bending the outer edge portion at a right angle, but if the uneven protrusions formed by the destruction of the connecting portion remain, the bending position of the height becomes uneven. The correct three-dimensional shape cannot be obtained because the outer edge is displaced. In addition, the broken pieces may cause the operator to cut their hands. Therefore, prior to the bending step, a work of completely scraping off the fragments of the connecting portion with a gold file is performed.

[0005]

In the above-mentioned conventional punching and molding method for the plate-like body, the projections formed by the fragments of the connecting portion remain. For this reason, there is a problem in that a considerable amount of labor and time are required for the work of completely scraping off these protrusions, which causes an increase in manufacturing cost.

[0006]

The punching method of a plate-shaped body according to the present invention is configured such that, in the punching-molding, a recess is formed in an outer edge portion connected to each connecting portion of the plate-shaped body. According to a preferred embodiment of the present invention, each connecting portion has a wedge shape whose width decreases as it approaches the end on the plate-shaped body side.

[0007]

According to the method for punching a plate-shaped body according to the present invention, a V-shaped recess or the like is formed at the outer edge of the plate-shaped body connected to each connecting portion at the time of punching, and the plate of each connecting portion is formed. The end on the body side is connected to this recess. When the plate-shaped body is separated from the original plate, the protrusion caused by the destruction of the connecting portion still remains on the plate-shaped body side.However, since this protrusion remains in the recess recessed from the outer edge of the plate-shaped body, residual debris is It does not project to the outside and does not adversely affect the subsequent bending process. As a result, the work of scraping off the residual protrusions with a file or the like becomes unnecessary. According to the preferred embodiment, the size of the residual protrusion can be reduced by forming the connecting portion into a wedge shape whose width decreases as it approaches the end on the plate-shaped body side.

[0008]

FIG. 1 is a plan view showing the shapes of a plate-shaped body and a connecting portion punched and formed by a punching and molding method according to an embodiment of the present invention. 10 is an original plate, and 11 and 12 are from this original plate 10. Punch-formed plate-shaped bodies, 13a to 13d are four connecting portions for temporarily fixing the punch-formed plate-shaped body 11 to the original plate 10, and 14a to 14d are formed on the outer edge portion of the plate-shaped body including the connecting portions. It is a V-shaped recess. The plate-shaped body 11 shows a state before being separated from the original plate 10, and the plate-shaped body 12 shows a state after being separated from the original plate 10 by breaking the connecting portion.

As illustrated by the punched plate-shaped body 11, the plate-shaped body 11 and the original plate 10 have wedge-shaped connecting portions 14a to 14a whose width becomes narrower toward the end on the plate-shaped body side.
V-shaped recesses are formed in the outer edge portion of the plate-shaped body 11 which is temporarily fixed by 4d and which is continuous with each connecting portion.

As illustrated by the punched plate-like body 12, the plate-like body 12 separated from the original plate 10 by the breaking of the connecting portion still has the projections 15a to 15d formed by the breaking of the connecting portion. . However, since these protrusions remain in the recessed portion that is recessed from the outer edge of the punched plate-shaped body 12, they do not project to the outside of the outer edge. Therefore, these debris do not adversely affect the subsequent bending step, and it is not necessary to remove them using a gold file or the like.

Further, the connecting portions 14a to 14d have the plate-like body 1
Since the width is narrower toward the first side, the connecting portion is broken in the vicinity of the narrow plate-shaped body 11 when separated from the original plate 10. Therefore, the protrusions remaining in the recesses become small, and these protrusions are effectively prevented from protruding outside the outer edge.

The plate-shaped body can be punched by using a single die for punching, but such a die is not versatile and is expensive. For this reason,
Prepare several types of small molds with standardized shapes such as rectangular shapes, and while appropriately selecting these small molds, automatically punch out the peripheral part of the plate-like body by numerical control etc. The method has been adopted.

FIG. 2 shows an example of the shapes of the two kinds of molds 21 and 22 used for punching the connecting portion in the above-mentioned punching molding. FIG. 3 shows these two types of molds 21 and 2.
2 shows how to punch the connecting part using 2. First, as shown in FIG. 3 (A), a general-purpose rectangular die is used to punch the right side of the connecting portion into a rectangular shape as shown by hatching. Next, the die 22 shown in FIG. 2 is used for punching as shown in FIG. 2B, the die 21 shown in FIG. 2 is used for punching as shown in FIG. The left side of the connecting portion is punched using a general-purpose rectangular die.

Since a recess for accommodating the residual protrusion of the connecting portion is formed in the plate-shaped body after punching, the recess is left in the housing formed by bending the molded plate-shaped body. When it is necessary to prevent the recesses from deteriorating the aesthetics of the product or causing the leakage of radio waves, the formation locations of these recesses are selected so as to be hidden inside the final product.

4A and 4B are views showing an example of a metal casing in which the above-mentioned recess is formed at a position hidden inside, FIG. 4A is a plan view showing the shape of a plate-shaped body after punching, and FIG. It is a perspective view of a housing formed by bending this plate-like body and then spot-welding a portion marked with X. Four recesses 41, 4 appearing on the outer edge of the punched plate-shaped body
2, 43 and 44 are formed at positions that do not appear outside the final product and do not cause radio wave leakage from the housing due to overlapping with other parts.

[1116]

Modified Example Although the case where the plate-shaped body to be punched and formed is a metal has been described above, the present invention can be applied to punching and molding of a plate-shaped body made of an appropriate material such as a resin or plastic plate.

Also, although the case where the V-shaped recess is formed has been illustrated, it is also possible to form the U-shaped recess having another appropriate shape.

Further, although the case where the wedge-shaped connecting portion is formed has been illustrated, the connecting portion having a uniform width may be formed.

Further, the case where the punched plate-like body is bent to form the housing has been exemplified, but it is not necessary to scrape the projection in order to prevent accidents such as cutting of the hand of the operator. The present invention is effective even in the case where bending is not performed.

[0020]

As described in detail above, in the punching method for a plate-shaped body according to the present invention, a recess is formed in the outer edge portion of the plate-shaped body including each connecting portion in the punching-molding, so that the connection is made. The protrusion caused by the breakage of the portion does not protrude beyond the outer edge. As a result, it is not necessary to scrape off the protrusions, and the labor and time of the work can be significantly reduced.

[Brief description of the drawings]

FIG. 1 is a plan view showing an example of a plate-shaped body punched and formed according to a method for punching and molding a plate-shaped body according to an embodiment of the present invention.

FIG. 2 is a plan view showing an example of the shape of a punching die used in the above embodiment.

FIG. 3 is a plan view for explaining a punching molding method of the above-described embodiment using the mold of FIG.

FIG. 4 is a plan view (A) and a perspective view (B) showing the shape of a housing that is stamped and formed according to an embodiment of the present invention and then assembled through a bending step.

FIG. 5 is a plan view showing an example of a plate-shaped body that is punch-molded according to a conventional punch-molding method.

[Explanation of symbols]

10 Original plate (flat plate) 11,12 Punch-formed plate-shaped body 13a to 13d Connection part 14a to 14d V-shaped recess 15a to 15d Protrusion 21, which is formed by destruction of the connection part remaining in the V-shaped recess 21, 22 Die for punching

Claims (4)

(57) [Claims] 1. A punching of a plate-like body for separating the plate-like body from the flat plate by punching and molding a plate-like body of a predetermined shape from a flat plate leaving a plurality of connecting portions. In the molding method, a recess is formed in an outer edge portion of the plate-shaped body that is continuous with each of the connecting portions when the plate-shaped body is punched-molded. 2. The punching-molding method for a plate-shaped body according to claim 1, wherein each of the connecting portions has a wedge shape whose width decreases as it approaches a connecting end with the plate-shaped body. 3. The punching-molding method for a plate-shaped body according to claim 1, wherein the recess has a V shape. 4. The punching of the plate-shaped body according to claim 1, wherein each of the connecting portions is formed at a position hidden inside a casing formed by bending the punched-molded plate-shaped body. Molding method.