Method for producing press-molded article

Abstract

The present disclosure pertains to a method for manufacturing a press-molded article provided with a plate-shaped part and a wall part, the press-molded article being manufactured by sandwiching a blank material by a first sandwiching structure positioned on a first side in a plate thickness direction with respect to the plate-shaped blank material, and a second sandwiching structure positioned on a second side in a plate thickness direction with respect to the plate-shaped blank material, and sandwiching the blank material by a second sandwiching structure positioned on a second side in a plate thickness direction with respect to the plate-shaped blank material. The second clamping structure is located on a second side in the plate thickness direction, which is opposite to the first side, with respect to the blank. The first die is moved in a direction parallel to the plate thickness direction and in a pressing direction in which the first die is relatively close to the blank to perform press forming, thereby forming a wall portion on the blank. The first die is further moved in the pressing direction to perform press forming, thereby forming a plate-shaped portion having a recessed portion on the blank.

Description

Technical Field

[0001] The present disclosure relates to a method for producing a press-formed product. Background Art

[0002] A technique for forming an extended flange on a plate-shaped blank by press forming is known. The extended flange is formed by, for example, bending the blank, and the bent portion, i.e., the ridgeline, has an arc shape that is concave relative to the blank.

[0003] Japanese Patent Application Laid-Open No. 2017-042826 discloses a technology in which, when an extended flange is formed on a blank by press forming, the blank is clamped and fixed by a punch and a block, thereby suppressing the generation of wrinkles on the blank. Summary of the invention

[0004] In addition to the extended flange, a press-formed product having a recessed portion recessed in the plate thickness direction formed in a plate-like portion that is located on the opposite side of the extended flange with respect to the ridgeline may be considered.

[0005] In the prior art disclosed in Japanese Patent Application Publication No. 2017-042826, when the extended flange and the recess are formed simultaneously by stamping, in order to form the recess by the punch and the pad that clamp the blank, it is necessary to form a convex portion protruding in the plate thickness direction on the punch or the pad. Therefore, when the blank is clamped by the punch and the pad, a gap exceeding the plate thickness is generated between the blank and the punch or between the blank and the pad due to the convex portion.

[0006] When the extended flange is formed by press forming with a gap between the blank and the punch or between the blank and the spacer, wrinkles are easily generated in the blank, especially when the blank is a material with a low elongation such as a high-strength material.

[0007] Therefore, in order to obtain a stamped product with an extended flange and a recess, it is necessary to form the recess in a process after the extended flange is formed to suppress wrinkles during the extended flange formation process. In addition, in order to form the recess, it is necessary to prepare a mold different from the mold used for the extended flange.

[0008] One aspect of the present disclosure is to reduce the man-hours required for stamping.

[0009] One scheme of the present disclosure is a method for manufacturing a stamped product, wherein the stamped product has a plate-like portion and a wall portion, wherein the plate-like portion has a recessed portion that is recessed in a first plate thickness direction, and the wall portion extends from an end of the plate-like portion in a direction that intersects the plate-like portion. The method for manufacturing the stamped product includes: clamping a blank; forming the wall portion on the blank; and forming the plate-like portion having the recessed portion on the blank.

[0010] Clamping the blank includes clamping the blank by a first clamping structure and a second clamping structure. The first clamping structure is located on a first side of the blank in a thickness direction, i.e., a second thickness direction, relative to the plate-shaped blank. The second clamping structure is located on a second side, i.e., an opposite side of the first side, relative to the blank in the second thickness direction.

[0011] Forming a wall portion on a blank includes: stamping a blank clamped by a first clamping structure and a second clamping structure by moving at least one of a first die and a clamping portion along a stamping direction, and forming a wall portion on the blank by the stamping. The first die is located on the first side compared to the blank. The clamping portion is a collection of a first clamping structure, a second clamping structure, a blank, and a second die. The stamping direction is a direction parallel to the second plate thickness direction and is a direction in which the first die is relatively close to the blank.

[0012] The forming of the plate-shaped portion having the concave portion on the blank includes: further moving at least one of the first die and the clamping portion along the stamping direction by bringing the first die and the second die closer to each other, thereby stamping the blank in a state where the wall portion is being formed, and forming the plate-shaped portion having the concave portion on the blank by the stamping. The second die is located on the second side relative to the blank.

[0013] According to the above configuration, the wall portion and the recessed portion can be formed on the blank by moving the object along the same stamping direction while the first die and the second die are respectively arranged on the first side and the second side of the blank in advance. Thus, the man-hours required for stamping can be reduced.

[0014] According to one embodiment of the present disclosure, forming the wall portion may include: forming the wall portion on the blank by moving the first die along the stamping direction. Forming the plate-shaped portion may include: forming a concave portion on the blank by further moving the first die along the stamping direction in a manner that the first die and the second die are close to each other so as to form a concave portion on the blank.

[0015] According to the above configuration, the wall portion and the recessed portion can be formed on the blank by moving the first die once in the punching direction. Therefore, the number of man-hours required for the punching process can be reduced.

[0016] In one embodiment of the present disclosure, the plate-like portion may have a first recess and a second recess. The first recess is configured as a recess. The second recess is shallower than the first recess and is recessed in the first plate thickness direction. Clamping the blank may include: clamping the blank by the first clamping structure and the second clamping structure, thereby forming the second recess on the blank.

[0017] According to the above configuration, when the blank is clamped by the first clamping structure and the second clamping structure, the second recessed portion which is shallower than the first recessed portion can be formed. Therefore, the number of man-hours required for press forming can be reduced.

[0018] In one embodiment of the present disclosure, clamping the blank may include: clamping the blank at at least two points separated from each other in a direction orthogonal to the second plate thickness direction by a first clamping structure and a second clamping structure. The at least two points may include a first point and a second point. Forming the plate-shaped portion may include: forming a recess on the blank by moving a portion of at least one of the first mold and the second mold so as to pass between the first point and the second point.

[0019] According to the above configuration, a recessed portion can be formed between two points of the blank that are clamped by the first clamping structure and the second clamping structure.

[0020] In one embodiment of the present disclosure, the blank may be made of a high-strength material, which may be understood as a high-tensile strength steel.

[0021] According to the above configuration, when a press-formed product is formed from a blank made of a high-strength material, it is possible to suppress the occurrence of cracks or wrinkles in the press-formed product. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 This is a schematic perspective view of a press-formed product.

[0023] Figure 2 It is a schematic three-dimensional diagram of an upper pad, a blank, a lower pad, and a lower mold.

[0024] Figure 3 It is a cross-sectional view of the blank and its surrounding structure along the stamping direction during the clamping process.

[0025] Figure 4 It is a cross-sectional view of the blank and its surrounding structure along the punching direction during the wall forming step.

[0026] Figure 5 It is a cross-sectional view of the blank and its surrounding structure along the punching direction in the top plate forming step.

[0027] Figure 6 It is an additional cross-sectional view related to the cross section of the blank and its surrounding structure along the punching direction during the clamping process.

[0028] Figure 7 It is an additional cross-sectional view related to the cross section of the blank and its surrounding structure along the punching direction during the wall forming process.

[0029] Figure 8 This is an additional cross-sectional view related to the cross section of the blank and its surrounding structure along the punching direction in the top plate forming process.

[0030] Fig. 9This is a cross-sectional view of a blank and its surrounding structure along the punching direction in a wall forming step according to another embodiment.

[0031] Fig.10 This is a cross-sectional view of a blank and its surrounding structure along the punching direction in a wall forming step according to another embodiment.

[0032] Fig.11 It is a schematic perspective view of a press-formed product according to another embodiment, in which a recessed portion is located at an end portion of a plate-like portion.

[0033] Fig.12 It is a schematic perspective view of a press-formed product according to another embodiment, in which a recessed portion extends from a first end portion to a second end portion of a plate-shaped portion.

[0034] Fig.13 It is a schematic perspective view of a press-formed product according to another embodiment, in which the recess has a gently convex shape.

[0035] Fig.14 This is a flowchart showing a method for manufacturing a press-formed product.

[0036] Fig.15A It is a three-dimensional image of other stamped products; Fig. 15B It is a top view of the stamped product; Fig. 15C This is a side view of a stamped product. DETAILED DESCRIPTION

[0037] Hereinafter, embodiments of the present disclosure will be described with reference to the drawings.

[0038] The embodiments of the present disclosure are not limited to the following embodiments, and various modes can be adopted within the technical scope to which the present disclosure belongs.

[0039] [1. First embodiment]

[0040] Figure 1 The stamped product 1 shown is an exemplary stamped product, which is used to explain the manufacturing method of the stamped product of the first embodiment. Figure 1 The stamped product 1 shown can be used to manufacture stamped products of various shapes. The manufacturing method of this embodiment can be used to manufacture stamped products of any shape, for example, the stamped product comprises: a plate-like portion having a recessed portion recessed in the direction of the plate thickness, and a wall portion extending from the end of the plate-like portion in a direction intersecting the plate-like portion.

[0041] [1-1. Composition of stamped products]

[0042] Figure 1The stamped product 1 shown is formed by stamping a metal material. The stamped product 1 is made of a high-tensile strength steel material having a high tensile strength, which is called a high-strength material. For example, the stamped product 1 can be made of a high-tensile strength steel material having a tensile strength of 980 MPa or more, or can be made of a high-tensile strength steel material having a tensile strength of 1180 MPa or more.

[0043] The press-formed component 1 includes a top plate portion 2 , a wall portion 3 , and a bottom plate portion 4 .

[0044] Except for a part, most of the top plate portion 2 extends on the same plane. The top plate portion 2 is plate-shaped. The top plate portion 2 may be bent in the plate thickness direction or may not be bent in the plate thickness direction. In the following, the plate thickness direction of the top plate portion 2 is referred to as the up-down direction. The plate thickness direction is not limited to the up-down direction, and may also be understood as the left-right direction or the front-back direction. "Up" and "down" in the up-down direction may be interchangeable.

[0045] The top plate portion 2 has a first upper recess 21 a , a first lower recess 21 b , a second upper recess 22 a , and a second lower recess 22 b .

[0046] When viewed from below the top plate 2, the first upper recess 21a is recessed toward the upper side at the top plate 2. When viewed from above the top plate 2, the first lower recess 21b is recessed toward the lower side at the top plate 2. The depths of the first upper recess 21a and the first lower recess 21b are both greater than the plate thickness of the top plate 2. That is, the upper surface of the top plate 2 in the area corresponding to the first upper recess 21a is located at an upper side compared with the upper surface of the top plate 2 in the surrounding area. The lower surface of the top plate 2 in the area corresponding to the first lower recess 21b is located at a lower side compared with the lower surface of the top plate 2 in the surrounding area.

[0047] When viewed from below the top plate 2, the second upper recess 22a is recessed toward the upper side at the top plate 2. When viewed from above the top plate 2, the second lower recess 22b is recessed toward the lower side at the top plate 2. The depths of the second upper recess 22a and the second lower recess 22b are both smaller than the plate thickness of the top plate 2. That is, the depths of the second upper recess 22a and the second lower recess 22b are both smaller than the depths of the first upper recess 21a and the first lower recess 21b.

[0048] The installation positions of the first upper recess 21 a , the first lower recess 21 b , the second upper recess 22 a , and the second lower recess 22 b are not limited as long as they are located on the top plate 2 .

[0049] The wall portion 3 extends from the end of the top plate portion 2 in a direction intersecting the top plate portion 2. The wall portion 3 has a plate shape. In the embodiment, the wall portion 3 extends from the end of the top plate portion 2 in a substantially downward direction.

[0050] The portion where the top plate 2 and the wall 3 are connected forms a ridgeline 3a. The ridgeline 3a is in a concave arc shape in a direction parallel to the upper surface of the top plate 2. Figure 1 As shown in FIG. 1 , the wall portion 3 is bent along the ridge line 3 a. The wall portion 3 corresponds to an extended flange formed at the end of the top plate portion 2 .

[0051] The bottom plate portion 4 extends from the end portion located on the opposite side of the ridge line 3a of the wall portion 3 in a direction intersecting the wall portion 3. The bottom plate portion 4 is plate-shaped. The bottom plate portion 4 extends on the side opposite to the direction in which the top plate portion 2 extends relative to the wall portion 3. Although not limited to this, in the present embodiment, the bottom plate portion 4 is substantially parallel to the top plate portion 2.

[0052] [1-2. Configuration of stamping device]

[0053] The stamped product 1 is formed by a stamping device 5 (see Figures 2 to 8 ) is formed by stamping a blank 10. The blank 10 is a plate-shaped component. In this embodiment, as an example, the blank 10 is a high-strength material made of metal.

[0054] like Figures 2 to 8 As shown, the press forming device 5 includes an upper die 61 , an upper cushion block 62 , an air cushion 63 , a lower die 71 , a lower cushion block 72 , and a die cushion 73 .

[0055] The upper die 61 is a die for press forming and has a top surface 61a, an upper contact portion 61b, an upper wall forming portion 61c, an upper bottom plate forming portion 61d, and an upper convex portion 61e.

[0056] The top surface 61a is a surface located on the lower side of the upper mold 61. The top surface 61a extends in a direction perpendicular to the up-down direction (hereinafter referred to as a horizontal direction).

[0057] The upper contact portion 61 b ​​protrudes downward from a portion of the top surface 61 a .

[0058] The upper side wall forming portion 61c is a surface extending in the following manner, that is, extending downward from a position lower than the upper side abutting portion 61b and away from the upper side abutting portion 61b in the horizontal direction. The upper side wall forming portion 61c is curved in a manner protruding toward the side where the upper side abutting portion 61b is located in the horizontal direction. The angle formed between the virtual surface extending the upper side wall forming portion 61c and the top surface 61a is substantially consistent with the angle formed between the top plate portion 2 and the wall portion 3 in the stamped product 1.

[0059] The upper bottom plate forming portion 61d is a surface that extends horizontally from the lower end of the upper side wall forming portion 61c and extends away from the upper side wall forming portion 61c. The upper bottom plate forming portion 61d is substantially parallel to the horizontal direction.

[0060] As Figures 6 to 8 shown, the upper convex portion 61e protrudes downward from a part of the lower side of the top surface 61a. The lower end of the upper convex portion 61e has a shape that protrudes downward for forming the first lower concave portion 21b in the stamping formed product 1.

[0061] The upper cushion block 62 is a cushion block for stamping. In the present embodiment, the cross-section of the upper cushion block 62 in the vertical direction is substantially rectangular. For example Figure 2 shown, the upper cushion block 62 has an upper first concave portion forming portion 62a, an upper second concave portion forming portion 62b, and an upper through hole 62c.

[0062] As Figure 2 and Figure 3 shown, the upper first concave portion forming portion 62a is formed on the lower surface of the upper cushion block 62. The upper first concave portion forming portion 62a is recessed upward. The upper first concave portion forming portion 62a has a shape for forming the first upper concave portion 21a in the stamping formed product 1.

[0063] As Figure 2 shown, the upper second concave portion forming portion 62b is formed on the lower surface of the upper cushion block 62. The upper second concave portion forming portion 62b is recessed upward or protrudes downward for forming the second upper concave portion 22a or the second lower concave portion 22b in the stamping formed product 1.

[0064] As Figure 2 and Figure 6 shown, the upper through hole 62c is a through hole that penetrates the upper cushion block 62 in the vertical direction.

[0065] As Figures 3 to 8 shown, the air cushion 63 is a cushion pad that utilizes the reaction force of compressed gas. The air cushion 63 expands or contracts in the vertical direction according to the pressure.

[0066] The upper surface of the air cushion 63 abuts against the lower surface of the top surface 61a. The lower surface of the air cushion 63 abuts against the upper surface of the upper cushion block 62. The lower surface of the air cushion 63 is located at a position lower than the upper abutting portion 61b.

[0067] The lower die 71 is a die for stamping. For example Figure 2 and Figure 3 shown, the lower die 71 has a bottom surface 71a, a lower abutting portion 71b, a lower side wall forming portion 71c, a lower bottom plate forming portion 71d, and a lower convex portion 71e.

[0068] The bottom surface 71a is a surface located on the upper side of the lower mold 71. The bottom surface 71a extends in the horizontal direction.

[0069] The lower contact portion 71 b protrudes upward from a portion of the bottom surface 71 a .

[0070] The lower side wall forming portion 71c is a surface extending in the following manner, that is, extending upward from a position higher than the lower side abutting portion 71b and away from the lower side abutting portion 71b in the horizontal direction. The lower side wall forming portion 71c is curved in a manner protruding toward the side where the lower side abutting portion 71b is located in the horizontal direction. In the stamping forming device 5, the upper side wall forming portion 61c and the lower side wall forming portion 71c are substantially parallel.

[0071] The lower bottom plate forming portion 71d extends from the lower end of the lower side wall forming portion 71c in the horizontal direction and is a surface extending away from the lower side wall forming portion 71c. The lower bottom plate forming portion 71d is substantially parallel to the horizontal direction.

[0072] The lower convex portion 71 e protrudes upward from a portion of the upper side of the bottom surface 71 a . The upper end of the lower convex portion 71 e has a shape that protrudes upward to form the first upper concave portion 21 a in the press-formed product 1 .

[0073] The lower pad 72 is a pad for stamping. In this embodiment, the cross section of the lower pad 72 in the vertical direction is substantially rectangular. Figure 2 As shown, the lower block 72 has a lower first recess forming portion 72a, a lower second recess forming portion 72b, and a lower through hole 72c.

[0074] like Figure 2 and Figure 6 As shown, the lower first concave array 72a is formed on the upper surface of the lower pad 72. The lower first concave forming portion 72a is recessed downward. The lower first concave forming portion 72a has a shape for forming the first lower concave portion 21b in the press-formed product 1.

[0075] like Figure 2 As shown, the lower second recess forming portion 72b is formed on the upper surface of the lower pad 72. The lower second recess forming portion 72b protrudes upward or is recessed from the lower side to form the second upper recess 22a or the second lower recess 22b in the stamped product 1.

[0076] like Figure 2 and Figure 3 As shown, the lower through hole 72 c is a through hole that penetrates the lower pad 722 in the up-down direction.

[0077] like Figures 3 to 8As shown, the die pad 73 is a buffer pad used for stamping. The die pad 73 expands or contracts in the up and down directions according to the pressure. The reaction force of the die pad 73 is greater than the reaction force of the air cushion 63.

[0078] The upper surface of the die pad 73 contacts the lower surface of the lower pad 72. The lower surface of the die pad 73 contacts the upper surface of the bottom surface 71a. The upper surface of the die pad 73 is located above the lower contact portion 71b.

[0079] like Figure 2 and Figure 3 As shown, the lower block 72 is arranged on the upper side of the lower die 71. The blank 10 is arranged on the upper side of the lower block 72. The upper block 62 is arranged on the upper side of the blank 10. By moving the upper die 61 from the upper side to the lower side of the upper block 62, the components arranged in the above manner are press-formed.

[0080] The stamping forming is not limited to moving only the upper die 61. The stamping forming can be performed by moving at least one of the upper die 61 and the clamping portion along the stamping direction, wherein the stamping direction is a direction parallel to the up-down direction and is a direction in which the upper die 61 is relatively close to the blank 10. The clamping portion is a set including the upper pad 62, the lower pad 72, the lower die 71, and the blank 10.

[0081] like Fig.14 As shown, the method for manufacturing the stamped product 1 includes a clamping step S10, a wall forming step S20, and a top plate forming step S30. The method for manufacturing the stamped product 1 is performed in this order.

[0082] [1-3. Method for manufacturing a press-formed product having a recessed portion recessed upward]

[0083] use Figures 3 to 5 The method of manufacturing the press-formed product 1 will be described with attention paid to the cross section including the first upper recessed portion 21 a and the wall portion 3 .

[0084] [1-3-1. Clamping process]

[0085] like Figure 3 As shown, the clamping step S10 is a step of clamping the blank 10 by the upper block 62 located above the blank 10 and the lower block 72 located below the blank 10 .

[0086] The upper cushion block 62 abuts against the upper surface of the blank 10. The lower cushion block 72 abuts against the lower surface of the blank 10. The upper cushion block 62 and the lower cushion block 72 clamp the blank 10 from the upper side and the lower side respectively. The upper cushion block 62, the lower cushion block 72, and the lower die 71 are configured such that the upper first concave portion 62a of the upper cushion block 62, the lower through hole 72c of the lower cushion block 72, and the lower convex portion 71e of the lower die 71 are arranged on substantially the same axis in the vertical direction.

[0087] At this time, under the action of the pressures of the upper cushion block 62 and the lower cushion block 72, the blank 10 deforms along the Figure 2 shown upper second concave portion forming portion 62b and lower second concave portion forming portion 72b. Thereby, a second upper concave portion 22a and a second lower concave portion 22b are formed on the blank 10. However, even after the second upper concave portion 22a and the second lower concave portion 22b are formed on the blank 10, the blank 10 can still slide in the horizontal direction.

[0088] Hereinafter, a virtual plane that is substantially in the same plane as the portion of the blank 10 that abuts against the upper cushion block 62 and the lower cushion block 72 is referred to as a reference plane A (see Figure 4 and Figure 5 ).

[0089] [1-3-2. Wall portion forming process]

[0090] As Figure 4 shown, the wall portion forming process S20 is a process of forming a wall portion 3 on the blank 10 by moving the upper die 61 downward to perform stamping on the blank 10 clamped by the upper cushion block 62 and the lower cushion block 72.

[0091] The upper side bottom plate forming portion 61d in the upper die 61 moves toward the surface of the upper side of the blank 10 that does not abut against the upper cushion block 62, thereby performing stamping on the blank 10 clamped in the clamping process S10.

[0092] Under the action of the pressure of the upper side bottom plate forming portion 61d, the portion of the blank 10 that abuts against the upper side bottom plate forming portion 61d deforms in such a way as to be located at a position lower than the reference plane A. At this time, the blank 10 bends downward from the end of the portion clamped by the upper cushion block 62 and the lower cushion block 72. Thereby, a ridge line 3a is formed on the blank 10. After that, the blank 10 deforms in such a way as to follow and abut against the upper side wall forming portion 61c. Thereby, the wall portion 3 is formed on the blank 10.

[0093] The upper die 61 moves downward in the wall forming step S20 until the upper abutting portion 61b abuts against the upper surface of the upper pad 62. At this time, the upper end of the upper wall forming portion 61c does not move to a position lower than the reference plane A. The blank 10 and the upper first recessed portion forming portion 62a are spaced apart from each other. The lower convex portion 71e is located at a position lower than the reference plane A.

[0094] The reaction force of the air cushion 63 is smaller than the reaction force of the die cushion 73. Therefore, in the wall forming step S20, due to the movement of the upper mold 61, the air cushion 63 is compressed downward by the top surface 61a and the upper cushion block 62. The die cushion 73 receives the downward pressure from the lower cushion block 72, but does not substantially deform.

[0095] [1-3-3. Top plate forming step]

[0096] like Figure 5 As shown, the top plate portion forming step S30 is a step of forming the top plate portion 2 having the first upper recess 21 a on the blank 10 by further moving the upper die 61 downward to perform press forming on the blank 10 in a state where the wall portion 3 is being formed.

[0097] In the top plate forming step S30, the upper mold 61 continues to move further downward on the basis of the wall forming step S20. At this time, the upper mold 61 moves downward in a state of abutting against the upper pad 62 at the upper side abutting portion 61b and abutting against the air cushion 63 at the top surface 61a. Therefore, the upper mold 61, the upper pad 62, and the air cushion 63 move downward as a whole. The top plate forming step S30 will be described below with a focus on the movement of the upper pad 62. The movement of the upper pad 62 downward means that the upper mold 61 and the air cushion 63 move the same distance as the upper pad 62 moves downward.

[0098] The lower convex portion 71e of the lower die 71 is located inside the lower through hole 72c of the lower block 72. The lower convex portion 71e and the upper first recess forming portion 62a of the upper block 62 are positioned substantially at the same position in the horizontal direction.

[0099] The portion of the blank 10 that abuts the upper block 62 and the lower block 72 is pressed downward by the upper block 62 , thereby moving downward together with the lower block 72 following the upper block 62 .

[0100] In the blank 10, the portion at the same position in the horizontal direction as the upper first concave portion forming portion 62a and the lower through hole 72c follows the upper pad 62 to move downward, thereby abutting against the upper end of the lower convex portion 71e. In addition, when the upper pad 62 moves downward, the lower pad 72 follows the upper pad 62 and moves relatively downward relative to the lower convex portion 71e. As the lower pad 72 moves relatively downward relative to the lower convex portion 71e, the lower convex portion 71e penetrates the lower through hole 72c and abuts against the blank 10. The portion of the blank 10 abutting against the lower convex portion 71e receives the upward pressure from the lower convex portion 71e and deforms in a manner that is recessed upward compared to the reference surface A. Furthermore, when the upper pad 62 moves downward, the upper surface of the portion of the blank 10 that abuts the lower convex portion 71e abuts the upper first concave portion forming portion 62a of the upper pad 62, and then further deforms along and abuts the outer surface of the upper first concave portion forming portion 62a. Thus, the first upper concave portion 21a is formed on the blank 10. In other words, the top plate portion 2 having the first upper concave portion 21a is formed on the blank 10.

[0101] In the top plate forming step S30, the upper pad 62 moves downward until the blank 10 is along and abuts against the outer surface of the upper first recess forming portion 62a. At this time, in the top plate forming step S30, the upper pad 62 can move downward until the lower pad 72 abuts against the upper surface of the lower abutting portion 71b. Due to the downward movement in the top plate forming step S30, the upper pad 62 reaches the bottom dead center.

[0102] When the upper pad 62 reaches the bottom dead center, the wall portion 3 formed on the blank 10 extends along and abuts against the upper side wall forming portion 61c and the lower side wall forming portion 71c. In the blank 10, the portion of the wall portion 3 extending from the end on the side opposite to the ridge line 3a extends along and abuts against the upper side bottom plate forming portion 61d and the lower side bottom plate forming portion 71d. Thus, the bottom plate portion 4 is formed on the blank 10.

[0103] In the top plate forming step S30, the distance between the top surface 61a of the contact air cushion 63 and the upper pad 62 is constant, so the air cushion 63 does not substantially deform. Due to the movement of the lower pad 72, the mold cushion 73 is compressed downward by the lower pad 72 and the bottom surface 71a.

[0104] As described above, the portion including the first upper recessed portion 21 a and the wall portion 3 in the press-formed product 1 is formed. Figure 5 The cross-sectional view of the blank 10 corresponds to Figure 1 VV cross-sectional view of the press-formed product 1.

[0105] [1-4. Method for manufacturing a press-formed product having a recessed portion recessed downward]

[0106] In the above, using Figures 3 to 5 Focus on Figure 1 The manufacturing method of the stamped product 1 is described with reference to the VV section of the stamped product 1. Figures 6 to 8 Focus on Figure 1 The manufacturing method of the press-formed product 1 will be described with reference to the VIII-VIII cross section of the press-formed product 1. That is, the manufacturing method of the press-formed product 1 will be described with reference to the cross section including the first lower recessed portion 21b and the wall portion 3 in the press-formed product 1.

[0107] [1-4-1. Clamping process]

[0108] In the clamping step S10, Figure 6 As shown in FIG. 1 , an upper die 61 and an upper pad 62 are arranged on the upper side of the blank 10. A lower pad 72 and a lower die 71 are arranged on the lower side of the blank 10. Figure 6 It is worth noting that the upper convex portion 61e of the upper mold 61, the upper through hole 62c of the upper pad 62, and the lower first concave forming portion 72a of the lower pad 72 are configured to form the first lower concave portion 21b. The upper mold 61, the upper pad 62, and the lower pad 72 are configured so that the upper convex portion 61e, the upper through hole 62c, and the lower first concave forming portion 72a are arranged on substantially the same axis in the up-down direction.

[0109] [1-4-2. Wall forming step]

[0110] In the wall forming step S20, Figure 7 As shown, the upper die 61 moves downward in the process in which the upper contact portion 61 b ​​contacts the upper surface of the upper block 62 , so that the upper convex portion 61 e contacts the upper surface of the blank 10 .

[0111] When the upper convex portion 61e abuts against the upper surface of the blank 10, the upper abutting portion 61b is spaced apart from the upper pad 62. The vicinity of the upper end of the upper wall forming portion 61c has not yet moved to a position lower than the reference surface A. The upper convex portion 61e is located inside the upper through hole 62c of the upper pad 62. The blank 10 and the lower first recess forming portion 72a are spaced apart from each other. The lower pad 72 abuts against the upper surface of the lower abutting portion 71b.

[0112] The portion of the blank 10 that abuts against the lower end of the upper side wall forming portion 61c (in other words, the portion where the upper side wall forming portion 61c and the upper bottom plate forming portion 61d are connected to each other) is deformed under the pressure of the upper side wall forming portion 61c so as to be located below the reference plane A. That is, the blank 10 is bent downward from the end of the portion sandwiched by the upper pad 62 and the lower pad 72. At this time, the blank 10 is in a state where the wall portion 3 is being formed on the blank 10.

[0113] [1-4-3. Top plate forming step]

[0114] like Figure 8 As shown, in the top plate forming step S30, the upper die 61 is further moved downward to press-form the blank 10 in the state where the wall 3 is being formed. As a result, the top plate 2 having the first lower recess 21b is formed on the blank 10.

[0115] In this step, the upper mold 61 is further moved downward in continuation of the wall portion forming step S20.

[0116] The upper protrusion 61 e is located inside the upper through hole 62 c in the upper block 62 .

[0117] In this process, the lower pad 72 abuts against the upper surface of the lower abutting portion 71b. Therefore, the downward movement of the lower pad 72 is restricted. The portion of the blank 10 abutting against the upper convex portion 61e is subjected to the downward pressure from the upper convex portion 61e, and is deformed in a manner concave toward the lower side compared to the reference surface A. When the upper mold 61 moves further downward, the lower surface of the portion of the blank 10 abutting against the upper convex portion 61e abuts against the lower first recess forming portion 72a of the lower pad 72, and is further deformed in a manner along and abutting against the lower first recess forming portion 72a. As a result, the first lower recess 21b is formed on the blank 10. In other words, the top plate portion 2 having the first lower recess 21b is formed on the blank 10.

[0118] In this process, the upper die 61 moves downward until the blank 10 is along and abuts against the lower first concave forming portion 72a. At this time, the upper die 61 can move downward until the upper abutting portion 61b abuts against the upper pad 62. The upper die 61 can move downward until the upper end of the upper side wall forming portion 61c abuts against the blank 10. The upper die 61 reaches the bottom dead center by moving downward in this process.

[0119] When the upper die 61 reaches the bottom dead center, the portion of the blank 10 between the upper side wall forming portion 61c and the lower side wall forming portion 71c extends along and abuts against the upper side wall forming portion 61c and the lower side wall forming portion 71c. Thus, the wall portion 3 is formed on the blank 10. In the blank 10, the portion of the wall portion 3 extending from the lower end extends along and abuts against the upper bottom plate forming portion 61d and the lower bottom plate forming portion 71d. Thus, the bottom plate portion 4 is formed on the blank 10.

[0120] In this process, the air cushion 63 is compressed downward by the top surface 61a and the upper cushion block 62 due to the movement of the upper mold 61. Since the distance between the bottom surface 71a of the contacting die cushion 73 and the lower cushion block 72 is constant, the die cushion 73 does not substantially deform.

[0121] As described above, the portion including the first lower recessed portion 21 b and the wall portion 3 in the press-formed product 1 is formed. Figure 8 The cross-sectional view of the blank 10 corresponds to Figure 1 This is a cross-sectional view of the press-formed product 1 taken along the line VIII-VIII.

[0122] [1-5. Action and effect]

[0123] According to the embodiments described in detail above, the following functions and effects can be obtained.

[0124] (1a) Figure 4 and Figure 7 In the wall forming step S20 shown in FIG. 1 , the press forming device 5 performs press forming by moving the upper die 61 downward, thereby forming the wall 3 on the blank 10. Figure 5 and Figure 8 In the top plate forming step S30 shown, the press forming device 5 performs press forming by further moving the upper die 61 downward, thereby forming the first upper recess 21a and the first lower recess 21b on the blank 10. In the top plate forming step S30, the upper die 61 continues to move downward on the basis of the wall forming step S20.

[0125] According to the above configuration, the upper die 61 moves downward only once in the wall forming step S20 and the top plate forming step S30. Therefore, the wall 3, the first upper recess 21a, and the first lower recess 21b can be formed on the blank 10 by one press forming. Thus, the man-hours required for the press forming can be reduced.

[0126] (1b) The depths of the second upper recess 22a and the second lower recess 22b are both smaller than the depths of the first upper recess 21a and the first lower recess 21b. The second upper recess 22a and the second lower recess 22b are formed on the blank 10 by receiving pressure from the upper pad 62 and the lower pad 72 in the clamping step S10.

[0127] According to the above configuration, the relatively shallow second upper recess 22a and second lower recess 22b can be formed when the blank 10 is clamped by the upper block 62 and the lower block 72. Thus, the number of man-hours required for press forming can be reduced.

[0128] In addition, the depths of the second upper recess 22a and the second lower recess 22b are both smaller than the plate thickness of the top plate 2. Therefore, when the second upper recess 22a and the second lower recess 22b are clamped by the upper pad 62 and the lower pad 72, it is possible to suppress the generation of a gap exceeding the plate thickness between the blank 10 and the upper pad 62 or between the blank 10 and the lower pad 72.

[0129] (1c) The first upper recess 21 a and the first lower recess 21 b are not sandwiched between the upper block 62 and the lower block 72 .

[0130] According to the above configuration, the relatively deep first upper recess 21a and first lower recess 21b are less likely to receive pressure from the upper pad 62 and the lower pad 72. Therefore, wrinkles or cracks can be suppressed from occurring in the first upper recess 21a and first lower recess 21b.

[0131] (1d) In the wall portion forming step S20 , the blank 10 is sandwiched between the upper block 62 and the lower block 72 .

[0132] According to the above configuration, when the blank 10 is bent downward in the wall portion forming step S20 , it is possible to suppress the blank 10 from wrinkling.

[0133] (1e) Even after the second upper recess 22a and the second lower recess 22b are formed on the blank 10 in the clamping step S10, the blank 10 can still slide in the horizontal direction. In the wall forming step S20, neither the first upper recess 21a nor the first lower recess 21b is formed on the blank 10.

[0134] According to the above configuration, when the blank 10 is bent downward in the wall forming step S20, the material flows into the bent portion of the blank 10 due to the sliding of the blank 10. Therefore, in the wall forming step S20, the blank 10 can be prevented from cracking.

[0135] [1-6. Correspondence between words]

[0136] In the above embodiment, the top plate portion 2 corresponds to an example of a plate-shaped portion, the upper side corresponds to an example of a first side in the plate thickness direction, and the lower side corresponds to an example of a second side in the plate thickness direction.

[0137] The upper block 62 is an example of a first clamping structure, the lower block 72 is an example of a second clamping structure, the upper mold 61 is an example of a first mold, and the lower mold 71 is an example of a second mold.

[0138] The first upper recessed portion 21 a and the first lower recessed portion 21 b correspond to an example of a recessed portion and a first recessed portion, and the second upper recessed portion 22 a and the second lower recessed portion 22 b correspond to an example of a second recessed portion.

[0139] In the portion of the upper block 62 adjacent to the upper through hole 62c, two points located on opposite sides of the upper through hole 62c in the radial direction of the upper through hole 62c correspond to an example of the first point and the second point.

[0140] In the portion of the lower block 72 adjacent to the lower through hole 72 c , two points located on opposite sides of the lower through hole 72 c in the radial direction of the lower through hole 72 c correspond to an example of the first point and the second point.

[0141] The clamping step S10 corresponds to an example of clamping the blank, the wall portion forming step S20 corresponds to an example of forming the wall portion on the blank, and the top plate portion forming step S30 corresponds to an example of forming a plate-shaped portion with a recessed portion on the blank.

[0142] [2. Other embodiments]

[0143] The embodiments of the present disclosure have been described above, but the present disclosure is not limited to the above embodiments and can be implemented in various forms.

[0144] (2a) In the above embodiment, the first upper recess 21a is formed by press forming along and abutting the upper first recess forming portion 62a of the upper pad 62. However, the structure for forming the first upper recess 21a is not limited to the first upper recess forming portion 62a. For example, Fig. 9 As shown, the press forming device 105 may include an upper die 161 having an upper recess 161 f and an upper block 162 having an upper through hole 162 c instead of the upper die 61 and the upper block 62 .

[0145] The upper recess 161f protrudes downward from a portion of the lower side of the top surface 61a. The lower end of the upper recess 161f has a shape that is recessed upward to form the first upper recess 21a in the press-formed product 1.

[0146] The upper through hole 162 c is a through hole in the upper cushion block 162 that penetrates the upper cushion block 162 in the up-down direction.

[0147] In this case, in the top plate forming step S30, the upper concave portion 161f is located inside the upper through hole 162c. The upper concave portion 161f is arranged instead of the upper first concave forming portion 62a. When the upper die 161 moves downward, the portion of the blank 10 abutting against the lower convex portion 71e receives the upward pressure from the lower convex portion 71e, thereby deforming in a manner concave upward compared to the reference surface A, and abutting against the upper concave portion 161f, thereby further deforming along and abutting against the upper concave portion 161f. Thus, the first upper concave portion 21a is formed on the blank 10.

[0148] (2b) In the above embodiment, the first lower recess 21b is formed by press forming along and abutting the lower first recess forming portion 72a of the lower pad 72. However, the structure for forming the first lower recess 21b is not limited to the first lower recess forming portion 72a. For example, Fig.10 As shown, the press forming device 205 may include a lower die 271 having a lower top surface 271 a and a lower recess 271 f instead of the lower die 71 and the lower block 72 .

[0149] The lower top surface 271a is a surface located on the upper side of the lower mold 271. The lower top surface 271a extends in the horizontal direction. In the clamping step S10, the wall forming step S20, and the top plate forming step S30, the lower top surface 271a contacts and clamps the lower surface of the blank 10.

[0150] The lower recessed portion 271f is formed on the lower top surface 271a. The lower recessed portion 271f is recessed downward. The lower recessed portion 271f has a shape for forming the first lower recessed portion 21b in the press-formed product 1.

[0151] In this case, in the top plate forming step S30, the lower surface of the portion of the blank 10 that abuts the upper convex portion 61e abuts the lower concave portion 271f instead of the lower first concave forming portion 72a, and is deformed along and abuts the lower concave portion 271f. Thus, the first lower concave portion 21b is formed on the blank 10.

[0152] In the above embodiment, the lower mold 271 corresponds to an example of the second clamping structure.

[0153] (2c) In the above embodiment, the first upper recess 21a is formed at a portion other than the end of the top plate 2. However, the formation position of the first upper recess 21a is not limited thereto. Fig.11 As shown, in the press-formed product 101, the first upper recess 121a may be formed in a portion of the top plate 102 that is connected to the wall 3. Alternatively, Fig.12As shown, in the press-formed product 201 , the first upper recess 221 a may be formed to extend from the end portion of the top plate portion 202 connected to the wall portion 3 to the end portion on the opposite side to the wall portion 3 .

[0154] (2d) In the above embodiment, the first upper recess 21a and the first lower recess 21b are both angular. However, the shapes of the first upper recess 21a and the first lower recess 21b may not be angular. For example Fig.13 As shown, in the press-formed product 301, the first upper recess 321a may be formed in a gently convex shape in the top plate portion 302. The first upper recess 321a may be a preliminary shape before being formed into an angular shape.

[0155] (2e) The manufacturing method of the above embodiment is used to manufacture an exemplary stamped product 1. However, the manufacturing method of a stamped product is not limited to being used to manufacture the stamped product 1. For example, as shown in FIG. 15 , it can be used to manufacture a stamped product 401 having the same structure as the stamped product 1.

[0156] The stamped product 401 includes a top plate 402, a wall 403, and a bottom plate 404, which respectively correspond to the top plate 2, the wall 3, and the bottom plate 4 in the stamped product 1. The portion where the top plate 402 and the wall 403 are connected forms a ridge 403a, which serves as a portion corresponding to the ridge 3a.

[0157] When the top plate 402 is bent in the plate thickness direction to form the stamped product 401 by the stamping device 5 , the surfaces of the upper and lower pads 62 and 72 that contact the blank 10 are bent in the direction in which the top plate 402 is bent.

[0158] The top plate portion 402 has a first upper recess 421a, a first lower recess 421b, a second lower recess 422a, and a second lower recess 422b as portions corresponding to the first upper recess 21a, the first lower recess 21b, the second upper recess 22a, and the second lower recess 22b, respectively.

[0159] The installation positions of the first upper recess 421 a , the first lower recess 421 b , the second upper recess 422 a , and the second lower recess 422 b are not limited as long as they are located on the top plate 402 .

[0160] For example, the press-formed product 401 may be used as a component constituting a vehicle body. The press-formed product 401 may also be used as a component constituting a vehicle other than the vehicle body. The press-formed product 401 may also be used as a component not installed in the vehicle.

[0161] (2f) In the above embodiment, the wall portion 3 has a shape corresponding to the extended flange. However, the shape of the wall portion 3 is not limited to the extended flange. For example, the shape of the wall portion 3 may be a bent flange or a contracted flange.

[0162] (2g) Multiple functions of one component in the above-mentioned embodiment may be realized by multiple components, or one function of one component in the above-mentioned embodiment may be realized by multiple components. In addition, multiple functions of multiple components may be realized by one component, or one function realized by multiple components may be realized by one component. In addition, part of the structure of the above-mentioned embodiment may be omitted. At least part of the structure of the above-mentioned embodiment may be added to the structure of the above-mentioned other embodiment, or at least part of the structure of the above-mentioned embodiment may be replaced with the structure of the above-mentioned other embodiment.

[0163] [Technical ideas disclosed in this specification]

[0164] [Project 1]

[0165] A method for manufacturing a stamped product, the stamped product comprising a plate-shaped portion and a wall portion, the plate-shaped portion having a recessed portion recessed in a first plate thickness direction, the wall portion extending from an end of the plate-shaped portion in a direction intersecting the plate-shaped portion, the method for manufacturing the stamped product being characterized in that it comprises the following steps:

[0166] The blank is clamped by a first clamping structure and a second clamping structure, wherein the first clamping structure is located on a first side of the blank in a plate thickness direction, i.e., a second plate thickness direction, relative to the plate-shaped blank, and the second clamping structure is located on a side opposite to the first side, i.e., a second side of the second plate thickness direction, relative to the blank;

[0167] The blank clamped by the first clamping structure and the second clamping structure is subjected to stamping by moving at least one of the first die and the clamping portion in a direction parallel to the second plate thickness direction and in a stamping direction in which the first die is relatively close to the blank, and the wall portion is formed on the blank by the stamping, wherein the first die is located on the first side compared to the blank, and the clamping portion is a collection of the first clamping structure, the second clamping structure, the blank, and the second die located on the second side compared to the blank; and

[0168] By further moving the first die and at least one of the clamping portion along the stamping direction in a manner that brings the first die and the second die closer, the blank in the state where the wall portion is being formed is stamped, and the plate-like portion having the recessed portion is formed on the blank through the stamping.

[0169] [Project 2]

[0170] The method for manufacturing a press-formed product according to item 1 is characterized in that:

[0171] The forming of the wall portion includes: forming the wall portion on the blank by moving the first die along the punching direction,

[0172] Forming the plate-shaped portion includes: further moving the first die along the punching direction so that the first die and the second die are brought close to each other so that the recessed portion is formed on the blank, thereby forming the plate-shaped portion having the recessed portion on the blank.

[0173] [Item 3]

[0174] The method for manufacturing a press-formed product according to item 1 or 2, characterized in that:

[0175] The plate-like portion has a first recessed portion as the recessed portion and a second recessed portion which is shallower than the first recessed portion and is recessed in the first plate thickness direction.

[0176] The clamping of the blank includes: clamping the blank by the first clamping structure and the second clamping structure, thereby forming the second recessed portion in the blank.

[0177] [Item 4]

[0178] The method for manufacturing a press-formed product according to any one of items 1 to 3, characterized in that:

[0179] Clamping the blank includes: clamping the blank at at least two points separated from each other in a direction orthogonal to the second plate thickness direction by the first clamping structure and the second clamping structure,

[0180] The at least two points include point 1 and point 2,

[0181] Forming the plate-shaped portion includes forming the recessed portion in the blank by moving a portion of at least one of the first die and the second die so as to pass between the first point and the second point.

[0182] [Item 5]

[0183] The method for manufacturing a press-formed product according to any one of items 1 to 4, characterized in that:

[0184] The blank is composed of a high-strength material.

Claims

1. A method for manufacturing a stamped product, the stamped product comprising a plate-shaped portion and a wall portion, the plate-shaped portion having a recessed portion recessed in a first plate thickness direction, the wall portion extending from an end of the plate-shaped portion in a direction intersecting the plate-shaped portion, the method for manufacturing the stamped product comprising the following steps: The blank is clamped by a first clamping structure and a second clamping structure, wherein the first clamping structure is located on a first side of the blank in a plate thickness direction, i.e., a second plate thickness direction, relative to the plate-shaped blank, and the second clamping structure is located on a side opposite to the first side, i.e., a second side of the second plate thickness direction, relative to the blank; The blank clamped by the first clamping structure and the second clamping structure is subjected to stamping by moving at least one of the first die and the clamping portion in a direction parallel to the second plate thickness direction and in a stamping direction in which the first die is relatively close to the blank, and the wall portion is formed on the blank by the stamping, wherein the first die is located on the first side compared to the blank, and the clamping portion is a collection of the first clamping structure, the second clamping structure, the blank, and the second die located on the second side compared to the blank; and By further moving the first die and at least one of the clamping portion along the stamping direction in a manner that brings the first die and the second die closer, the blank in the state where the wall portion is being formed is stamped, and the plate-like portion having the recessed portion is formed on the blank through the stamping.

2. The method for manufacturing a press-formed product according to claim 1, wherein: The forming of the wall portion includes: forming the wall portion on the blank by moving the first die along the punching direction, Forming the plate-shaped portion includes: forming the recessed portion on the blank by bringing the first die and the second die closer together, and further moving the first die along the stamping direction to form the plate-shaped portion having the recessed portion on the blank.

3. The method for manufacturing a press-formed product according to claim 1 or 2, characterized in that: The plate-like portion has a first recessed portion as the recessed portion and a second recessed portion which is shallower than the first recessed portion and is recessed in the first plate thickness direction. Clamping the blank includes: clamping the blank by the first clamping structure and the second clamping structure, thereby forming the second recess on the blank.

4. The method for manufacturing a stamped product according to claim 1 or 2, characterized in that: Clamping the blank includes: clamping the blank at at least two points separated from each other in a direction orthogonal to the second plate thickness direction by the first clamping structure and the second clamping structure, The at least two points include point 1 and point 2, Forming the plate-shaped portion includes forming the recessed portion in the blank by moving a portion of at least one of the first die and the second die so as to pass between the first point and the second point.

5. The method for manufacturing a press-formed product according to claim 1 or 2, characterized in that: The blank is composed of a high-strength material.

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