Cutting method of panel material using a press cutter

Abstract

To provide a press cutter which can suppress generation of cutting chips, at the time of cutting of a metal panel material.SOLUTION: A press cutter 1 includes an upper blade 10 and a lower blade 20. The upper blade 10 has a first surface 11 formed in a movement direction D of the upper blade 10, and a lower plane 12 which is perpendicular to the first surface 11 and is directed downward. An angle θ1 of the tip of the upper blade 10 is formed at a right angle by the first surface 11 and the lower plane 12 of the upper blade 10. The lower blade 20 has a second surface 21 which faces the first surface 11 at the time of cutting of the panel material P and is formed in the movement direction D, an upper plane 22 which is formed on a plane in parallel with the lower plane and is directed upward, and an inclined plane 23 which is formed continuous to the second surface 21 and the upper plane 22 between the second surface 21 and the upper plane 22, and is inclined relative to the upper plane 22. An angle θ2 of the tip of the lower blade 20 is formed at an obtuse angle by the second surface 21 and the inclined plane 23 of the lower blade 20.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] The present invention relates to a press cutter for cutting panel materials and a method for cutting panel materials using the same.

Background Art

[0002] Conventionally, as this type of technology, a press cutter having an upper blade and a lower blade has been proposed. This press cutter cuts a panel material by lowering the upper blade with respect to the metal panel material placed on the lower blade so as to sandwich the panel material between the upper blade and the lower blade. For example, Patent Document 1 proposes a press cutter having an upper blade and a lower blade with a blade tip shape corresponding to the uneven shape of the panel material.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, even when using the press cutter shown in Patent Document 1, a large amount of cutting chips may be generated during cutting of the panel material. In particular, even if the shape of the blade tip is formed on the shape of the panel material, when warpage occurs in the metal panel material, a gap is generated between the lower blade and the panel material, making it easier for cutting chips to be generated.

[0005] The present invention has been made in view of such problems, and an object thereof is to provide a press cutter capable of suppressing the generation of cutting chips during cutting of a metal panel material.

Means for Solving the Problems

[0006] In view of the above problems, the press cutter according to the present invention includes an upper blade and a lower blade. By lowering the upper blade with respect to a metal panel material placed on the lower blade, the panel material is sandwiched between the upper blade and the lower blade to cut the panel material. The upper blade has a first surface formed along the moving direction of the upper blade and a lower plane orthogonal to the first surface and facing downward. The angle of the cutting edge of the upper blade is formed at a right angle by the first surface and the lower plane. The lower blade includes a second surface facing the first surface when the panel material is cut and formed along the moving direction, an upper plane formed on a plane parallel to the lower plane and facing upward, and an inclined plane continuously formed between the second surface and the upper plane and inclined with respect to the upper plane. The angle of the cutting edge of the lower blade is formed at an obtuse angle by the second surface and the inclined plane.

[0007] According to the present invention, the panel material is placed on the upper plane of the lower blade so that the panel material contacts the upper plane of the lower blade and the portion of the panel material cut off from the panel material by the upper blade protrudes from the lower blade. Next, the upper blade is lowered. As a result, the panel material contacts the lower plane of the upper blade, and the panel material deforms along the inclined plane. In this deformed state, the panel material is cut while following the inclined plane forming the cutting edge. As a result, cracks due to shear stress are less likely to occur in the portion of the panel material in contact with the lower blade, and the generation of chips from the portion of the panel material in contact with the lower blade can be suppressed. In addition, since the cutting edge of the upper blade is at a right angle, the shear stress acting on the panel material can be reduced by the cutting edge of the upper blade, so that the generation of chips from the portion in contact with the upper blade can also be suppressed.

[0008] Here, as the present invention, a method for cutting a panel material using the above-described press cutter is disclosed. The cutting method according to the present invention includes an arranging step of arranging the panel material on the lower blade such that the panel material contacts the upper plane of the lower blade and a portion of the panel material to be cut off from the panel material by the upper blade protrudes from the lower blade, and a cutting step of lowering the upper blade and contacting the panel material with the lower plane of the upper blade to cut the panel material arranged on the lower blade in a state where the panel material is deformed along the inclined plane.

[0009] According to this cutting method, first, in the arranging step, the panel material is arranged on the lower blade such that a portion of the panel material to be cut off from the panel material by the upper blade protrudes from the lower blade. Next, in the cutting step, when the upper blade is lowered and the panel material is brought into contact with the lower plane of the upper blade to deform the panel material along the inclined plane, the generation of a gap between the panel material and the inclined plane is suppressed. As a result, cracks due to shear stress are less likely to occur in the portion of the panel material in contact with the lower blade, and the generation of chips can be suppressed from the portion of the panel material in contact with the lower blade. In addition, since the cutting edge of the upper blade is at a right angle, the shear stress acting on the panel material can be reduced by the cutting edge of the upper blade, so that the generation of chips from the portion in contact with the upper blade can also be suppressed.

Effect of the Invention

[0010] According to the present invention, the generation of chips can be suppressed when cutting a metal panel material.

Brief Description of the Drawings

[0011]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Embodiments for Carrying Out the Invention

[0012] Hereinafter, the press cutter according to the embodiment of the present invention will be described in detail with reference to the drawings.

[0013] 1. Regarding the press cutter 1 The press cutter 1 shown in Figs. 1 and 2 is a press cutter for lowering the outer panel and parts of an automobile, and is, for example, a device for punching a press-formed metal part (panel material) into a desired shape. Although not shown, the press cutter 1 includes an upper die and a lower die according to the shape of the workpiece. An upper blade is provided along the outer edge of the workpiece on the upper die, and a lower blade is provided at a position corresponding to the upper die on the lower die.

[0014] In this embodiment, among these upper blades and lower blades, the upper blade 10 and the lower blade 20 of the portion not restricted by the shape in the thickness direction of the panel material P are shown. Since the shapes of the other portions of the upper blade and the lower blade, and the shapes of the upper die and the lower die are generally known shapes, detailed descriptions thereof are omitted.

[0015] As shown in FIG. 2, the panel material P to be cut in this embodiment is obtained by processing a steel plate or an aluminum board by press forming or the like, and convex portions (surplus convex portions) Pa and concave portions (bead concave portions) Pb are formed, but it is not particularly limited to this shape. For example, the panel material P may be flat or may have a curved shape.

[0016] As shown in FIG. 2, in the panel material P having the convex portion Pa and the concave portion Pb, it is assumed that the convex portion Pa is likely to come into contact with the upper blade first, and the concave portion Pb comes into contact with the upper blade later. Even if it is not such a shape, a gap may be formed between the lower blade and the panel material P due to warping of the panel material P or the like. When cutting under these cutting conditions using ordinary upper and lower blades, excessive shear stress acts on the panel material P, and chips are likely to be generated. In this embodiment, in order to solve such a problem, the press cutter 1 has the following upper blade 10 and lower blade 20.

[0017] In this embodiment, the press cutter 1 includes an upper blade 10 and a lower blade 20, and cuts the panel material P by lowering the upper blade 10 so as to sandwich the panel material P between the upper blade 10 and the lower blade 20 with respect to the metal panel material P placed on the lower blade 20. The upper blade 10 and the lower blade 20 are made of, for example, tool steel or the like.

[0018] In this embodiment, as shown in FIG. 1, the upper blade 10 forms a blade tip 15 by a first surface 11 and a lower plane 12. The first surface 11 is formed along the moving direction D of the upper blade 10. In this embodiment, the first surface 11 is a plane formed along the vertical direction. The lower plane 12 is orthogonal to the first surface 11 and is a plane facing downward. In this embodiment, the lower plane 12 is formed to be slightly inclined with respect to the horizontal direction.

[0019] In this way, the angle θ1 of the cutting edge 15 of the upper blade 10 is formed at a right angle by the first surface 11 and the lower plane 12 of the upper blade 10. Here, as shown in FIG. 2, the cutting edge 15 of the upper blade 10 is the ridge line between the first surface 11 and the lower plane 12, and is monotonically inclined in the width direction W of the upper blade 10.

[0020] The lower blade 20 includes a second surface 21, an upper plane 22, and an inclined plane 23, and the second surface 21 and the inclined plane 23 form the cutting edge 25 of the lower blade 20. The second surface 21 is a plane that faces the first surface 11 and is formed along the moving direction D (vertical direction V) when cutting the panel material P.

[0021] A gap C is formed between the first surface 11 of the upper blade 10 and the second surface 21 of the lower blade 20. This gap C is set according to the thickness of the panel material P and the like. The upper plane 22 is formed on a plane parallel to the lower plane 12 of the upper blade 10 and faces upward. In this embodiment, the upper plane 22 is formed with a slight inclination with respect to the horizontal direction H.

[0022] Furthermore, the inclined plane 23 is formed continuously between the second surface 21 and the upper plane 22 and is inclined with respect to the upper plane 22. The inclined plane 23 faces the upper blade 10, and the angle θ2 of the cutting edge 25 of the lower blade 20 is formed as an obtuse angle by the second surface 21 and the inclined plane 23.

[0023] Here, the angle θ2 of the cutting edge 25 is preferably in the range of 100° to 120° based on the results of the inventor's experiments and the like. In this embodiment, the angle θ2 is 110°. Here, as shown in FIG. 2, the cutting edge 25 of the lower blade 20 is the ridge line formed by the second surface 21 and the upper plane 22, and is inclined in the same direction as the cutting edge 15 of the upper blade 10 in the width direction W of the lower blade 20.

[0024] Furthermore, it is preferable that the width W1 of the inclined plane 23 shown in FIG. 1 (the horizontal width between the second surface 21 and the upper plane 22) is equal to or greater than the width W2 in the same direction of the upper plane 22. For example, the width W1 of the inclined plane 23 is preferably 10 mm or more. By setting the width W1 of the inclined plane 23 as described above, when the panel material P is pushed downward by the upper blade 10, the panel material P deforms along the inclined plane 23 and easily follows the inclined plane 23. As a result, the gap between the panel material P and the inclined plane 23 can be eliminated, and the generation of chips due to shear stress can be suppressed.

[0025] 2. Cutting method of panel material P using press cutter 1 Hereinafter, a method for cutting the panel material P using the press cutter 1 according to the present embodiment will be described with reference to FIGS. 3(a) to 3(c).

[0026] First, as shown in FIG. 3(a), an arrangement step is performed. The panel material P is placed on the upper plane 22 of the lower blade 20 so that the panel material P contacts the upper plane 22 of the lower blade 20, and a portion (scrap portion) P1 of the panel material P to be cut off from the panel material P by the upper blade 10 protrudes from the lower blade 20. At this time, when the convex portion (excess convex portion) Pa and the concave portion (bead concave portion) Pb are formed, a gap may be formed between the upper plane 22 of the lower blade 20 and the panel material P.

[0027] Next, as shown in FIGS. 3(b) and 3(c), a cutting step is performed. Specifically, the upper blade 10 is lowered, and the panel material P is brought into contact with the lower plane 12 of the upper blade 10, thereby deforming the panel material P along the inclined plane 23. Here, when the convex portion Pa and the concave portion Pb are formed in the panel material P, these also plastically deform into a planar shape and follow the inclined plane 23. In the present embodiment, since the upper plane 22 of the lower blade 20 is formed on a plane parallel to the lower plane 12 of the upper blade 10, as the upper blade 10 descends, the panel material P easily follows the inclined plane 23.

[0028] In addition, a pressing mechanism may be provided to press a part of the panel material P except for the part facing the lower mold so as to prevent the panel material P from lifting due to the load of the upper blade 10. The pressing mechanism may be provided in the upper mold (not shown) part and may be restricted in vertical movement.

[0029] Finally, as shown in FIG. 3(c), with the panel material P deformed along the inclined plane 23, the panel material P disposed on the lower blade 20 is cut by the upper blade 10. As a result, the scrap portion (the portion to be cut off) P1 is cut off from the panel material P.

[0030] As described above, in the present embodiment, the panel material P is placed on the lower blade 20 such that the panel material P contacts the upper plane 22 of the lower blade 20, and the portion P1 of the panel material P that is cut off from the panel material P by the upper blade 10 protrudes from the lower blade 20. Next, the upper blade 10 is lowered.

[0031] As a result, the panel material P contacts the lower plane 12 of the upper blade 10, and the panel material P deforms along the inclined plane 23. This deformed state is a state in which the panel material P follows the inclined plane 23 forming the cutting edge 15, and in this state, the panel material P is cut.

[0032] As a result, cracks due to shear stress are less likely to occur in the portion of the panel material P in contact with the lower blade 20, and it is possible to suppress the generation of chips from the portion of the panel material P in contact with the lower blade 20. In addition, since the cutting edge 15 of the upper blade 10 is at a right angle, the shear stress acting on the panel material P can be reduced by the cutting edge 15 of the upper blade 10, so that the generation of chips from the portion in contact with the upper blade 10 can also be suppressed.

[0033] 3. Examples Hereinafter, with reference to FIGS. 4 to 6, examples conducted by the inventors in order to arrive at the present invention will be described together with comparative examples. FIG. 4(a) is a schematic perspective view of a press cutter according to Comparative Example 1, and FIG. 4(b) is a schematic perspective view of a press cutter according to Comparative Example 2.

[0034] As shown in Fig. 4(a), for the upper blade 50 according to Comparative Example 1, the cutting edge 55 is formed by the first surface 51 and the lower plane 52. The angle θ1 of the cutting edge 55 of the upper blade 50 is 80°. For the lower blade 60 according to Comparative Example 1, the cutting edge 65 is formed by the second surface 61 and the upper plane 62. The angle θ2 of the cutting edge 65 of the lower blade 60 according to Comparative Example 1 is 90°.

[0035] Furthermore, the lower blade 60 shown in Fig. 4(a) is a lower blade in which a groove portion 64 corresponding to the shape of the concave portion Pb is formed on the upper plane 62. On the other hand, as shown in Fig. 4(b), the difference between the lower blade 60 according to Comparative Example 2 and Comparative Example 1 is that the groove portion 64 is not formed on the upper plane 62, and the upper blade 50 according to Comparative Example 2 is the same as that of Comparative Example 1.

[0036] Using the upper blade 50 and the lower blade 60 shown in Figs. 4(a) and 4(b), the panel material P with the concave portion Pb formed was cut. As a result, it was found that when cutting the panel material P with the upper blade 50 and the lower blade 60 shown in Fig. 4(b), more cutting chips were generated compared to those shown in Fig. 4(a). This is presumably because when cutting the panel material P with the upper blade 50 and the lower blade 60 shown in Fig. 4(b), the concave portion Pb of the panel material P did not deform flatly according to the shape of the upper plane 62.

[0037] Furthermore, Fig. 5(a) shows the state of cutting the panel material P with the upper blade 50 and the lower blade 60 according to Comparative Example 2 shown in Fig. 4(b). As a result, as shown in Fig. 5(a), the panel material P tends to be deformed by the cutting edge 65 of the lower blade 60 and the cutting edge 55 of the upper blade 50, but there is almost no portion where the panel material P extends due to the cutting edge 55 of the upper blade 50. As a result, excessive shear stress acts on the panel material P by the cutting edge 65 of the lower blade 60 and the cutting edge 55 of the upper blade 50, and after cracks S1 and S2 occur, the panel material P is cut. As a result, it is considered that a large amount of cutting chips are generated from the panel material P.

[0038] Therefore, as shown in Fig. 5(b), the lower blade 20 according to the present embodiment was adopted as the lower blade. Fig. 5(b) is a schematic diagram for explaining the state of the panel material cut by the press cutter according to Comparative Example 3. Note that in the press cutter according to Comparative Example 3, the upper blade 50 is different from that of the present embodiment.

[0039] When using the press cutter according to Comparative Example 3, it was found that the amount of chips generated from the panel material P decreased compared to the case shown in Fig. 5(a). However, even in this case, it was confirmed that chips were generated from the portion of the panel material P that contacts the cutting edge 55 of the upper blade 50.

[0040] Therefore, as shown in Figs. 6(a) to (c), the cutting edge of the upper blade was examined. Fig. 6(a) is a schematic diagram for explaining the state of the panel material cut by the press cutter according to Comparative Example 3. Fig. 6(b) is a schematic diagram for explaining the state of the panel material cut by the press cutter according to the present embodiment. Fig. 6(c) is a schematic diagram for explaining the state of the panel material cut by the press cutter according to Comparative Example 4.

[0041] The upper blade shown in Fig. 6(a) is the same upper blade 50 as in Fig. 5(b), and the angle θ1 of the cutting edge 55 of the upper blade 50 is 80°. The upper blade shown in Fig. 6(b) is the upper blade 10 according to the present embodiment, and the angle θ1 of the cutting edge 15 of the upper blade 10 is 90° (right angle). The upper blade shown in Fig. 6(c) is the upper blade 70 according to Comparative Example 4, and the angle θ1 of the cutting edge 75 of the upper blade 70 is an obtuse angle. Specifically, the angle θ1 of the cutting edge 75 formed by the second surface 71 and the lower plane 72 is 110°. Note that in Comparative Examples 3 and 4, the lower blade used was the lower blade 20 shown in the present embodiment.

[0042] When the panel material P was cut using the upper blades 50, 10, and 70 shown in FIGS. 6(a) to 6(c), the amount of chips generated from the panel material P cut using the upper blade 10 shown in FIG. 6(b) was the least compared to that using the upper blades 50 and 70 shown in FIGS. 6(a) and 6(c). This is presumably because, with the upper blade 10 shown in FIG. 6(b), not only the cutting edge 15 of the upper blade 10 but also the lower plane 12 contacts the panel material P, reducing the shear stress acting on the panel material P.

[0043] On the other hand, since the cutting edge 55 of the upper blade 50 shown in FIG. 6(a) is an acute angle, as described above, a large shear stress was generated in the panel material P. Therefore, it is considered that the amount of chips generated from the panel material P was larger compared to that shown in FIG. 6(b). Also, since the cutting edge 75 of the upper blade 70 shown in FIG. 6(c) is an obtuse angle, the panel material P contacts first at a location other than the cutting edge 75. As a result, the apparent clearance between the upper blade 70 and the lower blade 20 increased, so it is considered that the amount of chips generated from the panel material P was larger compared to that shown in FIG. 6(b).

[0044] From the above, as shown in FIG. 6(b), it was found that if the panel material P is cut with a press cutter in which the angle of the cutting edge 15 of the upper blade 10 is a right angle and the angle θ2 of the lower blade 20 is an obtuse angle, the amount of chips generated from the panel material P can be suppressed.

[0045] Although the embodiments of the present invention have been described in detail above, the present invention is not limited to the above embodiments, and various changes can be made without departing from the spirit of the present invention described in the claims. The present invention can add the configuration of one embodiment to the configuration of another embodiment, replace the configuration of one embodiment with that of another embodiment, or delete a part of the configuration of one embodiment.

Explanation of Reference Numerals

[0046] 1: Press cutter, 10: Upper blade, 11: First surface, 12: Lower plane, 20: Lower blade, 21: Second surface, 22: Upper plane, P: Panel material

Claims

【Claim 1】 A press cutter that includes an upper blade and a lower blade, and cuts a panel material made of metal placed on the lower blade by lowering the upper blade so as to sandwich the panel material between the upper blade and the lower blade, wherein the upper blade has a first surface formed along the moving direction of the upper blade, and a lower plane orthogonal to the first surface and facing downward, and the angle of the cutting edge of the upper blade is formed at a right angle by the first surface and the lower plane, the lower blade has a second surface that faces the first surface and is formed along the moving direction during cutting of the panel material, and an upper plane formed on a plane parallel to the lower plane and facing upward, and an inclined plane that is continuously formed between the second surface and the upper plane and is inclined with respect to the upper plane, the angle of the cutting edge of the lower blade is formed at an obtuse angle by the second surface and the inclined plane, a method for cutting a panel material using a press cutter, wherein the horizontal width of the inclined plane between the second surface and the upper plane is equal to or greater than the horizontal width of the upper plane, the panel material is formed by press-molding a steel plate or an aluminum board to have convex portions and concave portions, the panel material is placed on the upper plane of the lower blade such that a portion of the panel material cut off from the panel material by the upper blade protrudes from the lower blade, with the panel material placed, the upper blade is lowered to bring the panel material into contact with the lower plane of the upper blade, so that a portion of the panel material including the convex portions and the concave portions is plastically deformed into a planar shape along the inclined plane, and with the portion of the panel material including the convex portions and the concave portions plastically deformed into a planar shape, the panel material placed on the lower blade is cut by the upper blade. A method for cutting a panel material using a press cutter, characterized by the above.

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