JPH0829370B2 - Shearing method for plate materials - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an improvement in a shearing method for a plate-shaped material such as a pressing prevention cover of a watt hour meter by a press or a metal case of a water meter. Is.

[Conventional technology]

FIG. 9 is a perspective view showing an anti-corrosion cover (hereinafter simply referred to as a cover) of a watt hour meter by a conventional plate material shearing method, in which (1) is a steel plate cover,
(2) is a notch for pulling in the wire, (3) is a knockout used by punching when pulling in the wire from another direction, (4) is fixing the cover (1) to a watt hour meter (not shown) The screw hole, (5) is a triangular protrusion for sealing, and the cover (1) is attached so as to cover the electric wire connecting portion (not shown) of the watt hour meter.

Next, a method of processing the cover (1) will be described. FIG. 10 is a perspective view showing the outer appearance of the cover body (11) in the intermediate step of the molding process. For convenience of production, two covers (1) are molded at the same time, and then the central portion is cut to separate each cover (1). ). First, after punching a steel plate into a predetermined shape with a press, the two pieces are integrated into a predetermined shape with a drawing depth slightly deeper than a predetermined depth D, as shown in FIG. After molding, the notch (2), the knockout (3), the hole (4), and the protrusion (5) are processed by pressing.

The notch (2) and the like are processed by a conventional shearing method. For example, details of the method for processing the protrusion (5) will be described. FIG. 11 is a cross-sectional view showing a machining tool,
FIG. 12 is a perspective view of the protrusion. In these figures,
Reference numeral (21) is a die, which has a triangular recess (21a). Reference numeral (22) is a punch, which has a tip portion (22a) which is triangularly projected so as to match the concave portion (21a) of the die. After the cover body (11) is fixed to the die (21) at a predetermined position, the punch (22) is moved from the lower side to the upper side in FIG. 11 to form the triangular protrusion (5) shown in FIG. To be done. At this time, as shown in FIGS. 11 and 12, burrs (5a) are formed in a sharp edged shape downwards on both side surfaces of the punch (22). Subsequently, the dashed-dotted line A portion in FIG. 10 is cut by a press to remove an unnecessary portion (12), and the double-dashed dashed line B portion in the central portion of FIG. Let it be the cover (1) shown. In addition, (13) is a scrap portion which is discarded when it is divided into two pieces. After this,
The burrs of the end faces (1a), (1b), the notches (2), the holes (4), and the protrusions (5) caused by cutting and hole processing are removed. Removing the burr prevents the risk of cuts caused by the burr during handling, and when the cover (1) is painted, the burr is sharp and the adhesion of the paint is poor, causing rust. This is to prevent

[Problems to be Solved by the Invention]

According to the conventional shearing method for plate-shaped materials, as described above, the notch (2), the hole (4), the protrusion (5), the end face (1a),
A burr occurs in (1b). Therefore, for the above-mentioned reason, the burr must be removed, and several steps are required to remove the burr, which requires a long processing time.

The present invention has been made to solve the above problems, and it is not necessary to remove burrs by positively generating burrs in a state where they do not pose a problem, and the processing time can be shortened. It is an object to provide a shearing method for a plate material.

[Means for solving the problem]

The shearing method of the plate-shaped material according to the present invention, a die having a recessed portion and a punch having an end surface larger than the recessed portion end surface of the die are opposed to each other, and the plate-shaped material is sandwiched between the opposing surfaces.
The punch is bitten into this plate-shaped material to a depth shallower than the thickness of the plate-shaped material, and the plate-shaped material is extruded into the recessed part of the die to form a protrusion, and at the same time, on the upper surface of the outer periphery of the recessed part of the die. Forming a thin part and pressing the protruding part from the recessed part of the die in the direction opposite to the bite direction of the punch, bending the thin part toward the center of the plate thickness of the plate-shaped material and processing Is.

[Action]

According to the present invention, by punching the punch into a depth shallower than the thickness of the plate-shaped material, the plate-shaped material is pressed and pushed out into the recessed portion of the die to form a protrusion, and the recessed portion of the die is formed. A thin part is formed on the upper surface of the outer peripheral part of the die, and the pressing part presses the plunge part from the recessed part of the die in the direction opposite to the biting direction of the punch to bend the thin part toward the center of the thickness of the plate-shaped material and break it. By letting
The burr of the plate-shaped material and the protruding part is bent toward the center of the plate-shaped material in the thickness direction and does not project like a knife on the surface of the plate-shaped material, so it may be cut or scratched during handling and the adhesion of the surface coating Does not decrease.

Example of Invention

1 to 4 show an embodiment of the present invention.
FIG. 12 shows a case where a triangular protrusion (5) in the conventional example shown in FIG. 12 is formed. FIG. 1 (a) is a sectional view of a punch portion showing a biting step, and FIG. FIG. 2 (a) is a cross-sectional view of a pressing member portion showing a separating step, FIG. 2 (b) is a perspective view showing the pressing member, FIG. 3 is a perspective view showing formed protrusions, and FIG. The drawing is a cross-sectional view showing the state of adhesion of the paint to the protrusions when painted.

First, a tool used in the bite process will be described. In FIG. 1, (51) is a die, which is provided with a square hole (51a) having a width W1 and a depth D1 which is a recess. (Five
2) is a punch, and as shown in the figure (b), it has a rectangular shape with a width W2 wider than the width W1 of the square hole (51a) of the die and a depth D2 shorter than the depth D1 of the square hole (51a). And is driven in the vertical direction in FIG. 1 (a) by a press (not shown).
Insert the cover body (11) between the die (51) and the punch (52) facing each other, and lower the punch (52) to the steel plate (11a) that is a plate-shaped material that forms the cover body (11). FIG. 1A to a predetermined depth (T-t) smaller than the plate thickness T.
Let it bite as shown in. The steel plate (11a) is pressed by the punch (52) to form a recess (21) and a protrusion (22) in the square hole (51a) of the die. At this time, the width W2 of the punch (52) is
Since it is made larger than the width W1 of a), it is shown in Fig. 1 (a).
As shown in Fig. 5, a strip-shaped thin portion (23) having a thickness t and a width of (W2-W1) / 2 is formed between the steel plate (11a) and the protruding portion (22) along the depth direction of the punch (52). Are formed on the left and right. In addition,
As for the portion along the width direction of the punch (52), the depth D2 of the punch (52) is shorter than the depth D1 of the square hole (51a) of the die (see FIG. 1 (b)), so the steel plate (11a) is crushed. The original thickness T remains unchanged. The shape (thickness t, width about (W2-W1) / 2) of the thin wall portion (23) is determined so that the thin wall portion (23) breaks and causes burr in the separation step described later, that is, It is determined by selecting the dimensions of the square hole (51a) of the die, the punch (52) and the bite depth (T-t).

Next, in the separation process, triangular protrusions (24) (Fig. 3)
To form. The tool used in this step will be described. In FIG. 2, (53) is a pedestal and has a rectangular hole (53
a), which has a width W3 slightly wider than the width W1 of the square hole (51a) of the die and a depth D3 having substantially the same dimension as the depth D2 of the punch. Reference numeral (54) is a pressing member, and as shown in FIG. 2 (b), the tip has a rectangular shape protruding in a triangular shape, and its width W4 and depth D4 are the width W1 of the square hole (51a) of the die. , Which are smaller than the depth D1 and are vertically driven by a press.

The projection (24) is formed as follows using the cradle (53) and the pressing member (54). In advance, cradle (53)
The pressing member (54) and the pressing member (54) are attached to the press so as to face each other at a predetermined position. The protrusion (22) is aligned with the position of the hole (53a) of the cradle to fix the cover body (11), and the protrusion (22) is fixed from below in FIG. 2 (a) by the pressing member (54). Push up to the position. Then, the thin portion (23) is pulled and stretched and finally ruptured, and the protruding portion (22) was separated from the steel plate (11a) at the portion of the thin portion (23), and the triangular protrusion (Fig. 3). 24) is formed (the upper and lower parts of the protrusion (24) are connected to the steel plate (11a) without being separated). At this time, the thin portion (23) is broken so that a burr is generated, and the burr (23a) on the cover body (11) side is projected upward in FIG.
The burr (23b) on the 4) side occurs downward in the figure, and does not project outwardly from each surface in the shape of a sharp knife, but falls.

By the way, in the above embodiment, the dimensions of the punch (52) and the die (51) and the thickness t of the thin portion (23) are set to the following values with the plate thickness of the steel plate (11a) as T. For example, a desired burr can be generated.

W2 (Punch width) -W1 (Die square hole width) = (0.4 to 1.
0) T Thickness of thin portion t = (0.1 to 0.4) T These values also change depending on the shape of the punch or die.

In addition, in this embodiment, since the triangular protrusion (24) is formed, in order to prevent the upper and lower parts of the protrusion (24) from being separated from the steel plate (11a), D1 (the depth of the square hole of the die is ) -D2 (punch depth) = 4T is selected.

Further, in the separation step, the protrusion (22) is formed on the steel plate (11
Since it is only separated from a), the hole in the cradle (53
The dimensions of a) and the pressing member (54) may be selected as described above, and the punch (52) and the square hole (51) of the die may be selected.
It has a wider selection range than the dimensional relationship of a).

The triangular protrusion (24) formed as described above is
Since the burr (23b) does not project outward, the risk of damage due to handling is reduced, and when the paint is applied, the paint (25) will completely cover the burr (23b) as shown in Fig. 4. Since it adheres so as to cover it, there is no risk of rusting from this part. The same applies to the burr (23a) portion of the recessed portion (21) that remains as a hole.

In addition, in the above-mentioned one embodiment, the case where the triangular protrusion (24) is formed has been described, but if the protrusion (22) in FIG. 1 (a) is completely separated from the steel plate (11a) and removed, the concave portion is formed. A square hole corresponding to the installation portion (21) is formed. In this case, the depth dimension of the die square hole (51a) is D2 (punch depth) -D1 (die square hole depth) = (0.4
.About.1.0) T 2 so that the thin portion (23) is formed even along the width direction of the punch (52) so as to be separated over the entire circumference of the protruding portion (22).

FIGS. 5 and 6 show another embodiment of the present invention. FIG. 5 (a) is a sectional view of a punch portion showing a biting step, and FIG. 5 (b) is a pressing step showing a separating step. FIG. 6 is a cross-sectional view of the member portion, and FIG. 6 is a cross-sectional view showing a state in which the paint is attached to the square hole portion of the steel plate after the triangular protrusions are separated. In this embodiment, a punched portion (62a) is provided slightly above the tip portion of the punch (62) and has a taper portion (62a) that spreads upward at an angle of 45 degrees from the width W2 of the tip portion and the width of the upper portion is W5. When digging into (11a), taper part (21
a) is formed. In addition, (65)
Is a holding plate, and the punch (62) is made into a steel plate (11) by a coil spring (67) provided between the press plate and the fixing part (66).
The steel plate (11a) is being pressed when it bites into a).
The rectangular hole (53a) of the cradle (53) has a width W6 which is slightly wider than the tapered portion (21a) of the recessed portion. Since other configurations are similar to those of the embodiment shown in FIGS. 1 and 2, the corresponding components are designated by the same reference numerals and the description thereof will be omitted.

As mentioned above, the taper part (21a) is provided on the upper part of the recessed part (21).
However, by configuring the punch (62) to be formed, even if the projection (24) is slightly swollen and its width becomes wider in the separation step of FIG. Because of this, no galling occurs with the steel plate (11a). Therefore, the inner surfaces of the left and right side surfaces of the triangular protrusion (24) and the recessed portion (21) serving as a square hole are clean. Therefore, for example, when coating is performed, the adhesion state of the coating material on this surface becomes good. Steel plate (11a) when painted on Fig. 6
The adhesion state of the coating material (25) to the recessed portion (21) and the burr (23a) which are square holes is shown.

FIG. 7 is a sectional view of a punch portion in a biting step showing another embodiment of the present invention. The punch portion (72) is enlarged slightly from the tip end portion width W2 to the upper portion width W7. The enlarged portion (72a) is provided in an arc shape.
In the bite process, the steel plate (11a) is pushed by the enlarged portion (72a) of the punch (72) to form the enlarged portion (21b) at the upper part of the recessed portion (21), which is the same as the embodiment of FIG. In, the protrusion (24) (protrusion (22)) and the steel plate (11
Prevent galling from occurring between a). In addition, by making the enlarged portion (72a) arcuate, the reaction force applied to the punch (72) can be rapidly increased as the depth of the punch (72) biting into the steel plate (11a) becomes deeper in the biting process. It is possible to prevent the bite depth (T-t) from becoming too deep by stopping by using it. Protrusion (2
In addition to the formation of 4), the notch (2) in the conventional example shown in FIG. 10, the processing of the screw hole (4) and the cutting along the one-dot chain line A and the two-dot chain line B can be performed in the same manner. For example, FIG. 8 shows a hole (4) for a screw in a conventional example.
It is an embodiment in the case of performing the punching process of the hole (34) corresponding to, and (a) is a biting step and (b) is a sectional view showing a separating step. In the figure, (81) is a die having a round hole (81a) having a diameter Φ1 which is a recess, (82) is a punch having a diameter Φ2 and a truncated cone-shaped tip having a taper angle of 15 °, and (83) is A pedestal with a hole (83a) of diameter Φ3, (8
4) is a pressing member, which is a round bar with a diameter of Φ4. In this case, the diameters Φ2 and Φ1 of the punch (82) and the round hole (81a) of the die are selected as follows so that the desired burr occurs.

Φ2 (diameter of punch tip) -Φ1 (diameter of round hole of die)
= (0.4 to 1.0) T Thickness of thin part t2 = (0.1 to 0.4) T In addition, the diameter (Φ3) of the pedestal hole (83a) and the pressing member (84)
The diameter Φ4 may be selected in the same way as the embodiment shown in FIG.

The procedure for processing the screw hole (34) is the same as that of the embodiment shown in FIGS. 1 and 2, but in this embodiment, the hole (81a) of the die is recessed. The thinned portion (33) of the protruding portion (32) (Fig. 8 (a)) formed by rupture is completely separated from the steel plate (11a), and then the screw hole (34) is formed. Thus, burrs (33a) and (33b) similar to those in the embodiment of FIG. 5 (b) are generated in the hole (34) and the separated protrusion (32). At this time, the hole (34)
Since it spreads upward, it is possible to prevent galling. The separated protrusion (32) is discarded as scrap.

The hole (83a) of the pedestal in the embodiment of FIG. 8 is not indispensable, and depending on how to select the shape of the thin portion (33), the protruding portion (32) may be separated even if it is not necessary. .

In short, according to the material and thickness of the plate-shaped material and the processing shape, that is, punching, straight line cutting, cutting out of the protrusion, etc., the dimensions of the punch and die, the shape of the thin portion, and the object of the present invention It may be decided to generate a burr such as

〔The invention's effect〕

As described above, according to the present invention, since the burr is bent and broken toward the plate thickness center side of the plate-shaped material so as not to cause a problem in the separation step, it is not necessary to remove the burr, It is possible to provide a shearing method for a plate-shaped material that can shorten the processing time.

[Brief description of drawings]

1 to 4 show an embodiment of the present invention. FIG. 1 (a) is a sectional view of a punch portion showing a biting step, FIG. 1 (b) is a perspective view of the punch, and FIG. (A) is a cross-sectional view of the pressing member showing the separation step, (b) is a perspective view showing the pressing member, FIG. 3 is a perspective view showing the formed protrusions, and FIG. Cross-sectional view showing the adhered state, FIG. 5,
FIG. 6 shows another embodiment of the present invention. FIGS. 5 (a) and 5 (b) are cross-sectional views, FIG. 6 is a cross-sectional view showing the adhesion state of paint, and FIG. 7 is the present invention. 8 is a sectional view showing another embodiment of the present invention, FIGS. 8 (a) and 8 (b) are sectional views showing another embodiment of the present invention, and FIGS. FIG. 9 is a perspective view of the anti-corrosion cover, FIG. 10 is a perspective view of the cover body in an intermediate step, and FIG. 11 is a cross-sectional view of a machining tool.
The figure is a perspective view of the protrusion. In the figure, (11a) is a steel plate, (21) is a recess, and (2)
2) and (32) are protrusions, (23) and (33) are thin-walled parts, and (23)
a), (23b), (33a), (33b) are burr, (24) is a protrusion, (34) is a hole for screw, (51), (81) is a die, (51)
a) and (81a) are holes in the die, (52), (62), (72),
(82) is a punch, and (54) and (84) are pressing members. In the drawings, the same reference numerals indicate the same or corresponding parts.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Nobuyuki Tagashi No.8 Midoricho, Fukuyama-shi, Hiroshima Mitsubishi Electric Corporation Fukuyama Manufacturing Co., Ltd. (56) References JP 61-219430 (JP, A) Actual development Sho 58 -89124 (JP, U)

Claims (1)

[Claims] 1. A die having a recessed portion and a punch having an end surface larger than the recessed portion of the die are opposed to each other, a plate-like material is sandwiched between the opposed surfaces, and the punch is a plate-shaped material on the plate-shaped material. Of the plate material is pushed into the recessed portion of the die to form a protruding portion, and a thin portion is formed on the upper surface of the outer peripheral portion of the recessed portion of the die, and the die. The plate-shaped material is pressed from the recessed portion by a pressing member in a direction opposite to the punching direction of the punch in a direction opposite to the biting direction of the punch, and the separation step of bending and breaking the thin portion toward the plate thickness center side of the plate-shaped material. A method of shearing a plate material to be processed.