JPH057946A - Punching method for pressed parts - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a punching method for a press part having a chamfered part on the outer circumference, in which "drip" or "burr" does not occur on the outer peripheral end face. [Structure] In a member 9 for processing, a concave portion 10 is surface-pressed in a previous step, and the concave portion 10 has a horizontal bottom surface 11 and an inclined surface 12. The cutting line 15 of the die 13 and the punch 14 of the press die is offset by C from the intersection 18 of the bottom surface 11 and the inclined surface 12 of the recess 10. When the member 9 is pressed by the die 13 and the punch 14, the member 9 is sheared along the cutting line 15, so that the inclined surface 12 which is a part of the recess 10 is pressed on the outer periphery of the member 9 as in the case of pressing. The surface pressing portion is formed as a flat shape. here,
Since the breaking line 19 is sheared toward the intersection 18, "burr" or "burr" does not occur.

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 a pressed part having a chamfered portion on its outer circumference.

[0002]

2. Description of the Related Art In recent years, there has been an increasing number of processing methods in which many parts of a pressed part are processed simultaneously by a progressive die, a transfer press or the like.

Conventionally, as a punching method for this kind of press portion, there has been a processing method as shown in FIGS. Hereinafter, the processing method will be described with reference to the drawings.
As shown, FIG. 3 shows a motor bracket (not shown)
It is often used for the above, and the surface pressing portion 2 is provided on the outer periphery of the product 1. As the processing method, the member 3 punched in the previous step as shown in FIG. 4 is pressed by the pad 5 against the member 3 placed on the plate 4 in the next step, and the inclined surface 7 of the surface pressing punch 6 The surface pressing portion 2 was formed on the outer periphery thereof. At this time, a droop 8 is formed on the outer periphery of the member 3 by plastic deformation as shown in FIG. Further, as another conventional processing method, as shown in FIG. 6, in the previous step, the concave portion 10 of the processing member 9 is surface-pressed in advance to form the concave portion 1.
0 has a horizontal bottom surface 11 and an inclined surface 12. Then, it was cut by the die 13 and the punch 14 of the press die. At this time, the cutting line 15 was made to come to the inclined surface 12. The surface pressing portion 16 formed by this processing method has a burr 17 on its end surface.

[0004]

However, the above-described conventional processing method has a drawback that when the surface pressing portion 2 is processed by the surface pressing punch 6, a droop 8 is formed.
The method in which the recess 10 is pressed in the previous step and then punched has a problem that the burr 17 is generated.

The present invention solves the above-mentioned conventional problems, and provides a method for punching a press part capable of eliminating the occurrence of "sag" or "burr" on the end face even if a chamfered portion is provided on the outer periphery of the product. The purpose is to provide.

[0006]

In order to achieve the above object, the present invention provides a member in which a concave portion having a bottom and an inclined surface is pressed in the previous step, and a die for punching the outer periphery in the concave portion of the member. And a punch, and the cutting line of the die and the punch is located outside the intersection of the bottom surface of the concave portion of the member and the inclined surface.

[0007]

In the above structure, since the cutting line of the die and the punch is located outside the intersection of the bottom surface of the recess and the inclined surface of the member, the fracture surface due to cutting becomes the intersection of the bottom surface of the recess and the inclined surface. , "Who" or "burr" does not occur.

[0008]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In the present embodiment, the same components as those shown in FIG. 6 of the above-mentioned conventional example are designated by the same reference numerals, and the description thereof will be omitted. As shown in the figure, in the member 9 for processing, the recess 10 is surface-pressed in the previous step, and the recess 10 has a horizontal bottom surface 11 and an inclined surface 12.
have. The cutting line 15 of the die 13 and the punch 14 is defined by an intersection 18 of the bottom surface 11 of the recess 10 and the inclined surface 12.
Only C is moved to the outside. At this time, if the C dimension is too large, "burrs" occur, and if the C dimension is too small, "burrs" occur. Therefore, it is necessary to determine an appropriate value of the C dimension, and the appropriate value varies depending on the dimension t of the cut surface of the member 9, and the dimension t changes depending on the plate thickness of the member 9 and the depth of the recessed portion 10. The value of C at which 19 intersects with the intersection 18 was experimentally determined. The optimum value at this time was t × (0.05 to 0.2).

In the above structure, when the member 9 is pressed by the die 13 and the punch 14, it is sheared along the breaking line 19, and the inclined surface 12 which is a part of the recess 10 is pressed on the outer periphery of the member 9. The surface pressing portion 20 is formed in a shape similar to that when pressed. At this time, since the break line 19 is sheared toward the intersection point 18, "burr" or "burr" does not occur.

C where the break line 19 intersects with the intersection 18
The value of varies depending on the material of the work piece and the clearance of the press die, and is set according to each condition before mass production.

[0011]

As is apparent from the above-described embodiments, the stamping method for press parts according to the present invention has a member in which a concave portion having a bottom and an inclined surface is surface-pressed in the previous step, and an outer periphery of the concave portion of the member. It consists of a die and a punch for punching, and the cutting line of the die and the punch is located outside the intersection of the bottom surface of the concave portion of the member and the inclined surface. Even if a chamfered portion is provided, it is possible to eliminate the occurrence of "sore" and "burr".

[Brief description of drawings]

FIG. 1 is a sectional view of an essential part of a punching method for a press part according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view of a chamfer formed by a punching method of the pressed portion.

FIG. 3 is an external perspective view of a product having a conventional chamfered portion.

FIG. 4 is a sectional view of a main part of a conventional chamfering method.

FIG. 5 is a sectional view of a chamfer formed by the same chamfering method.

FIG. 6 is a cross-sectional view of an essential part of another conventional punching method for press parts.

FIG. 7 is a cross-sectional view of a chamfered portion formed by the punching method of the pressed part.

[Explanation of symbols]

 9 Member 10 Recess 12 Sloping surface 13 Die 14 Punch 15 Cutting line 18 Intersection

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Nobuhiro Okada 1006 Kadoma, Kadoma City, Osaka Prefecture Matsushita Electric Industrial Co., Ltd.

Claims (1)

Claims: What is claimed is: 1. A member comprising a member having a bottomed and recessed inclined surface which has been pressed in the preceding step, and a die and a punch for punching the outer periphery of the member. A punching method for a pressed part, wherein the cutting line of the punch is located outside the intersection of the bottom surface of the concave portion of the member and the inclined surface.