JPH02187221A - Blanking method for sheet metal part - Google Patents

Abstract

PURPOSE:To easily manufacture a sheet metal part provided with thin wall projections by using a die and a punch the thickness between which are made larger in some places than in the residual places. CONSTITUTION:The clearances between the die 3 and the punch 4 are not fixed in each part and it is made slightly larger in some places by fine grooves 40 formed on the inner wall surface of the side of the punch 4. When a metallic sheet stock is blanked by such die 3 and punch 4, the metallic sheet stock is cut finely in small clearance parts but a terminal sheet 1 is torn off the metallic sheet when the clearance is increased a little. A blanked terminal sheet 1 is provided with thin wall projections 11 at the torn off places and the terminal sheet 1 integrated with thin wall projections 11 can be formed by a blanking die 3 and a blanking punch 4 only and by the blanking stage only.

Description

[Detailed description of the invention] [Industrial application field]

The present invention relates to a method for cutting sheet metal parts such as terminal boards.

[Conventional technology]

As shown in FIG. 3, there is a terminal plate 1 provided in a device such as a breaker, which has a thin protrusion 11 integrally projecting from a side edge. This terminal board] is the device body 2.
When mounting the terminal board 1 on the terminal board, the protrusions 11 protruding from the side edges are dug into the side walls of the terminal board mounting part formed as a groove, or the terminal board 1 is inserted into the dovetail-shaped terminal board mounting part. Press-fitting prevents removal and unnecessary movement. In order to form a terminal board with such thin protrusions as a sheet metal component, conventionally, pressing was performed to form the thin protrusions, and then the terminal plate was cut using a die cutter.

[Problem M that the invention attempts to solve]

For this reason, not only is production time-consuming, but two types of molds, one for pressing and one for punching, are required, which increases the cost required for the molds. The present invention has been devised in view of these points, and its purpose is to provide a method for cutting out sheet metal parts by which sheet metal parts having thin protrusions can be easily manufactured.

[Means to solve the problem]

Therefore, the present invention is characterized in that a sheet metal part is punched using a die and a punch that have a larger clearance in some parts than in other parts. [Operations] According to the present invention, the sheet metal part is torn off at the portion where the clearance between the die and the punch is large;
As a result, thin protrusions are formed on the sheet metal part. [Example] The present invention will be described in detail below based on the illustrated example.
In the figure, 3 is a die and 4 is a punch, and the terminal board 1 is punched out from a raw metal plate by these two, but the clearance between the die 3 and the punch 4 is not constant at each part. , a part of which is slightly enlarged by a minute edge 40 formed on the inner wall surface on the punch 4 side. The clearance value for this type of material depends on the hardness of the material metal plate, but it is usually kept at about 3% of the plate thickness, but in the case where Clear 40 is installed, the clearance value is kept at about 5% of the plate thickness. It is assumed that they have it. When punching a raw metal plate with the die 3 and punch 4 formed in this way, the raw metal plate is cut cleanly in areas where the clearance is small, but in areas where the clearance is slightly increased, as shown in Fig. 2. As shown, since the terminal plate 1 is torn off from the raw metal plate, the punched terminal plate 1 is provided with a thin protrusion 11 at the torn part, and the die 3 for punching is The terminal plate 1 integrally provided with the thin protrusion 11 can be formed using only the punch 4 and the punching process.

【Effect of the invention】

As described above, in the present invention, sheet metal parts with thin protrusions can be formed using only a die for punching, and a special process for forming the protrusions is not required. Not only is it easier to manufacture parts, but it is also possible to reduce mold costs and downsize the mold.

[Brief explanation of the drawing]

FIG. 1 is a cutaway perspective view of a punch and die according to an embodiment of the present invention, FIG. 2 is a sectional view of the same, and FIG. 3 is a perspective view of a terminal plate, which is a sheet metal part, where 1 is a terminal plate; 3 is a die, 4 is a punch, and 11 is a protrusion. Agent Patent Attorney Ishi 1) Long 74...Punch 11...Protrusion 3rd bacterium ■ Figure 2 Procedural amendment spontaneously) Name of the invention Method for cutting sheet metal parts 3, person making the amendment Related Patent Applicant Address 1048 Kadoma, Kadoma City, Osaka Name (58
3) Matsushita Electric Works Co., Ltd. Representative Toshio Miyoshi 4 Agent postal code 530 Date of amendment order Number of claims increased by voluntary amendment None [2] Figures 2 and 3 of the drawings are attached as attached. Correct to.

Claims (1)

[Claims] (1) A method for punching out a sheet metal part, which comprises punching out a sheet metal part using a die and a punch that have a larger clearance in some parts than in other parts.