Pressing device, mold, and method for manufacturing press-formed products

Abstract

The present invention provides a press apparatus, a mold, and a method for manufacturing press-formed products that can form press-formed products with a pair of wall sections of different heights in a single process while suppressing the occurrence of deflection. [Solution] The press device 10 includes a first mold 12 having a punch 20, a holder 22, and a support portion 24 that supports the holder 22; a second mold 14 having a die 40, a holder 42, a support portion 44 that elastically supports the holder 42, and restricting portions 46, 48 that restrict the movement of the holder 42; and a support portion 16 that elastically supports the support portion 24. The restricting portions 46, 48 restrict the holder 42 from being pushed towards the second mold 14 when the holder 22 has been pushed towards the second mold 14 by a predetermined amount. When the pushing of the holder 42 towards the second mold 14 is not restricted by the restricting portions 46, 48, the load required to push the holder 22 towards the first mold 12 is greater than the load required to push the holder 42 towards the second mold 14.

Description

Technical Field

[0001] The present invention relates to a press device, a mold, and a method for manufacturing a press-formed product.

Background Art

[0002] In automobiles, it is required to achieve both fuel efficiency improvement and collision property improvement, and high-strength automotive skeletal parts are used. High-strength skeletal parts can be manufactured, for example, by performing cold pressing on a high-strength material (such as high-strength steel), or by heating the material and then performing press forming, and using a hot stamping method in which the material is held by a mold at the bottom dead center and cooled to perform quenching.

[0003] As such automotive skeletal parts, molded products of various shapes having a pair of wall portions (for example, molded products having a hat-shaped or U-shaped cross-sectional shape) are used. In such molded products, the heights of the pair of wall portions may be equal or different.

[0004] When manufacturing a molded product with different heights of a pair of wall portions by cold pressing, for example, it is conceivable to separate the forming process of the wall portion with a lower height and the forming process of the wall portion with a higher height. However, in this case, the manufacturing process of the molded product becomes complicated. Therefore, it is desired to complete the forming in one step. Also, in hot stamping, as described above, quenching is performed by holding the material with a mold at the bottom dead center and cooling. Therefore, when manufacturing a molded product by hot stamping, it is also necessary to complete the forming in one step.

[0005] A method for forming a molded product in which a pair of wall sections of different heights are formed in a single process is disclosed, for example, in Patent Document 1. In the press forming method disclosed in Patent Document 1, the forming of the taller wall section begins by pushing the die toward the punch while the portion of the blank that will become the top plate of the press-formed product is sandwiched between the punch and the pad. Next, the forming of the shorter wall section begins by pushing the die further toward the punch. After that, the forming of the pair of wall sections of different heights is completed by moving the die to the bottom dead center. [Prior art documents] [Patent Documents]

[0006] [Patent Document 1] Japanese Patent Publication No. 2016-221558 [Overview of the project] [Problems that the invention aims to solve]

[0007] As a result of our investigation, we found that in the press forming method disclosed in Patent Document 1, when forming the taller wall portion, the portion of the blank that will become the shorter wall portion is prone to bending. The bent portion may remain as a wrinkle when it is formed into the shorter wall portion.

[0008] Therefore, the present invention aims to provide a press apparatus, a mold, and a method for manufacturing a press-formed product that can form a press-formed product in a single step while suppressing the occurrence of deflection, in which a pair of press-formed products having different wall heights can be formed. [Means for solving the problem]

[0009] (1) A press device according to one embodiment of the present invention is A first mold having a punch, a first holder, and a first support portion that supports the first holder and is movable in the pressing direction relative to the punch, A die, a second holder, a second support portion that supports the second holder so that the second holder can move back and forth relative to the die in the pressing direction, and a restricting portion that restricts the movement of the second holder in the pressing direction, and a second die facing the first die in the pressing direction, It comprises a third support portion that supports the first support portion, In the pressing direction, the side on which the first die is located as seen from the second die is defined as the first die side, and the side on which the second die is located as seen from the first die is defined as the second die side, and one side in the direction perpendicular to the pressing direction is defined as the first lateral side, and the other side as the second lateral side. The punch has a punch top surface facing the second die side, a first punch shoulder provided on the first lateral edge of the punch top surface, a second punch shoulder provided on the second lateral edge of the punch top surface, a first punch wall surface extending from the first punch shoulder towards the first die side, and a second punch wall surface extending from the second punch shoulder towards the first die side. The first holder is positioned on the first lateral side of the first punch wall surface, The first support portion supports the first holder from the first mold side, The die includes a first die shoulder corresponding to the first punch shoulder, a second die shoulder corresponding to the second punch shoulder, a first die wall corresponding to the first punch wall, a second die wall corresponding to the second punch wall, a third die shoulder provided on the first die-side edge of the first die wall, and a fourth die shoulder provided on the first die-side edge of the second die wall. The fourth die shoulder portion is provided on the first die side of the third die shoulder portion, The second holder is positioned to face the first holder on the first lateral side of the third die shoulder, The second support portion is configured to elastically support the second holder from the second die side, and is connected to the die so as to move relative to the punch in the pressing direction in conjunction with the relative movement of the die relative to the punch. The third support portion elastically supports the first support portion from the first mold side, The restricting unit restricts the second holder from being pushed relative to the die toward the second mold when the second holder is pushed relative to the die toward the second mold by a predetermined amount. When the pushing of the second holder toward the second die relative to the die is not restricted by the restricting portion, the load required to push the first holder toward the first die relative to the punch is greater than the load required to push the second holder toward the second die relative to the die. With the pushing of the second holder toward the second die relative to the die restricted by the restricting portion, the die moves toward the first die relative to the punch, causing the first holder to be pushed toward the first die relative to the punch by the second holder.

[0010] (2) The punch is the first punch wall surface The It has a first punch support surface that extends to the first lateral side with respect to the edge of the mold side, The die has a first die support surface extending from the third die shoulder to the first lateral side, The second holder may be supported by the second support portion such that it does not protrude toward the first die side beyond the first punch support surface.

[0011] (3) The second type may include a pad positioned opposite the top surface of the punch.

[0012] (4) The top surface of the punch may have a curved portion that curves when viewed from the pressing direction or the perpendicular direction.

[0013] (5) The above-described press apparatus manufactures a press-formed product having a top plate portion, a first wall portion extending from the first edge of the top plate portion in the thickness direction of the top plate portion, and a second wall portion extending from the second edge of the top plate portion in the thickness direction and having a length in the thickness direction longer than that of the first wall portion, from a blank made of a metal sheet, With the blank held between the first and second holders, the die is moved relative to the punch toward the first die until the regulating portion restricts the second holder from being pushed toward the second die, and the blank is pushed toward the first die by the fourth die shoulder, thereby advancing the formation of the second wall. With the pushing of the second holder toward the second die relative to the die restricted by the restricting portion, the die may be moved relative to the punch toward the first die to form the second wall portion, and the first wall portion may be formed by pushing the first holder toward the punch toward the first die with the second holder, while the blank is pushed toward the first die with the third die shoulder portion.

[0014] (6) A mold relating to one embodiment of the present invention is A first mold having a punch, a first holder, and a first support portion that supports the first holder so that the first holder can move back and forth in the pressing direction relative to the punch, A die, a second holder, a second support portion that supports the second holder so that the second holder can move back and forth relative to the die in the pressing direction, and a second die that has a restricting portion that restricts the movement of the second holder in the pressing direction and faces the first die in the pressing direction, In the pressing direction, the side on which the first die is located as seen from the second die is defined as the first die side, and the side on which the second die is located as seen from the first die is defined as the second die side, and one side in the direction perpendicular to the pressing direction is defined as the first lateral side, and the other side as the second lateral side. The punch has a punch top surface facing the second die side, a first punch shoulder provided on the first lateral edge of the punch top surface, a second punch shoulder provided on the second lateral edge of the punch top surface, a first punch wall surface extending from the first punch shoulder towards the first die side, and a second punch wall surface extending from the second punch shoulder towards the first die side. The first holder is positioned on the first lateral side of the first punch wall surface, The first support portion elastically supports the first holder from the first mold side. The die has a first die shoulder corresponding to the first punch shoulder, a second die shoulder corresponding to the second punch shoulder, a first die wall surface corresponding to the first punch wall surface, a second die wall surface corresponding to the second punch wall surface, a third die shoulder provided at an edge on the first mold side of the first die wall surface, and a fourth die shoulder provided at an edge on the first mold side of the second die wall surface. The fourth die shoulder is provided closer to the first mold side than the third die shoulder. The second holder is disposed to face the first holder on the first side lateral side with respect to the third die shoulder. The second support portion is configured to be able to elastically support the second holder from the second mold side, and is connected to the die so as to move relative to the punch in conjunction with the relative movement of the die with respect to the punch in the pressing direction. The restricting portion restricts the second holder from being pushed into the second mold side relative to the die when the second holder is pushed into the second mold side relative to the die by a predetermined amount. In a state where the pushing of the second holder into the second mold side with respect to the die is not restricted by the restricting portion, the load required to push the first holder into the first mold side with respect to the punch is greater than the load required to push the second holder into the second mold side with respect to the die. In a state where the pushing of the second holder into the second mold side with respect to the die is restricted by the restricting portion, when the die moves toward the first mold side with respect to the punch, the first holder is pushed into the first mold side relative to the punch by the second holder.

[0015] (7) The method for manufacturing a press-formed product according to an embodiment of the present invention is A method for manufacturing a press-formed product having a top plate portion, a first wall portion extending from a first edge of the top plate portion in the thickness direction of the top plate portion, and a second wall portion extending from a second edge of the top plate portion in the thickness direction and having a length in the thickness direction longer than that of the first wall portion, using the above-described press apparatus or die, from a blank made of a metal plate, comprising: While sandwiching the blank between the first holder and the second holder, the die is relatively moved toward the first mold side with respect to the punch until the pushing of the second holder toward the second mold side with respect to the die is restricted by the restricting portion, and the blank is pushed toward the first mold side by the fourth die shoulder portion to advance the forming of the second wall portion. With the pushing of the second holder toward the second mold side with respect to the die restricted by the restricting portion, the die is relatively moved toward the first mold side with respect to the punch to form the second wall portion, and while the second holder pushes the first holder toward the first mold side with respect to the punch, the blank is pushed toward the first mold side by the third die shoulder portion to form the first wall portion.

Advantages of the Invention

[0016] According to the present invention, a press-formed product having a pair of wall portions with different heights can be formed in one step while suppressing the occurrence of deflection.

Brief Description of the Drawings

[0017] [Figure 1A] FIG. 1A is a perspective view of a press-formed product. [Figure 1B] FIG. 1B is a plan view of a press-formed product. [Figure 2] FIG. 2 is a schematic view showing a cross section of a conventional press apparatus. [Figure 3] FIG. 3 is a schematic view showing a cross section of a press apparatus according to an embodiment of the present invention. [Figure 4] FIG. 4 is a schematic plan view showing a punch. [Figure 5]Figure 5 is a diagram illustrating the method for manufacturing a press-formed product according to this embodiment. [Figure 6] Figure 6 is a diagram illustrating the method for manufacturing a press-formed product according to this embodiment. [Figure 7] Figure 7 is a diagram illustrating the method for manufacturing a press-formed product according to this embodiment. [Figure 8] Figure 8 is a diagram illustrating the method for manufacturing a press-formed product according to this embodiment. [Figure 9] Figure 9 is a diagram illustrating the method for manufacturing a press-formed product according to this embodiment. [Figure 10] Figure 10 is a schematic diagram showing a modified press apparatus. [Figure 11] Figure 11 is a schematic diagram showing a press apparatus relating to another modification. [Figure 12] Figure 12 is a schematic diagram showing a press apparatus relating to other modifications. [Figure 13] Figure 13 is a schematic diagram showing a press apparatus relating to yet another modification. [Figure 14] Figure 14 is a perspective view showing a press-formed product according to a modified example. [Figure 15] Figure 15 is a plan view showing a press-formed product relating to another modification. [Figure 16] Figure 16 is a side view showing a modified punch. [Figure 17] Figure 17 is a schematic diagram showing a cross-section of a mold according to one embodiment of the present invention. [Figure 18] Figure 18 is a schematic diagram showing a cross-section of the mold related to the modified example. [Modes for carrying out the invention]

[0018] (Press-formed product) First, a brief description will be given of press-formed products manufactured by a press apparatus according to an embodiment of the present invention. Press-formed products manufactured by a press apparatus according to an embodiment of the present invention are used, for example, as structural components for automobiles such as rear side members, A-pillars, roof rails, and front side members. Figures 1A and 1B are schematic diagrams showing an example of a press-formed product manufactured by a press apparatus according to an embodiment of the present invention, where Figure 1A is a perspective view of the press-formed product and Figure 1B is a plan view of the press-formed product.

[0019] As shown in Figure 1A, the press-formed product 1 has a hat shape in a cross-section perpendicular to the longitudinal direction. Specifically, the press-formed product 1 has a top plate portion 2, a first wall portion 3, a second wall portion 4, a first flange 5, and a second flange 6.

[0020] In this embodiment, the top plate portion 2 is formed flat. The first wall portion 3 is formed to extend from one edge 2a (first edge) in the width direction of the top plate portion 2 to the thickness direction of the top plate portion 2. The second wall portion 4 is formed to extend from the other edge 2b (second edge) in the width direction of the top plate portion 2 to the thickness direction of the top plate portion 2. The first flange 5 is formed to extend from the edge 3a of the first wall portion 3 opposite to the top plate portion 2 to the outside of the press-formed product 1 (opposite side of the second wall portion 4). The second flange 6 is formed to extend from the edge 4a of the second wall portion 4 opposite to the top plate portion 2 to the outside of the press-formed product 1 (opposite side of the first wall portion 3). In this embodiment, in the thickness direction of the top plate portion 2, the length of the second wall portion 4 is longer than the length of the first wall portion 3. Note that the shape of the top plate portion 2 is not limited to a flat shape. For example, the top plate portion 2 may have a flat portion and a groove that is recessed relative to the flat portion. Furthermore, the top plate portion 2 may have a protrusion that extends outward from the flat portion. Also, the top plate portion 2 may have a circular or rectangular seating surface. Moreover, in a cross section perpendicular to the longitudinal direction of the press-formed product 1, the top plate portion 2 may have an arc-shaped curve. The same applies to the first wall portion 3, the second wall portion 4, the first flange 5, and the second flange 6.

[0021] As shown in Figures 1A and 1B, a curved portion 7 is provided in the central part of the press-formed product 1 in the longitudinal direction. In this embodiment, the curved portion 7 is a part that curves in an arc shape when viewed from above.

[0022] (Conventional molding method) Figure 2 shows an example of a conventional forming method for forming the press-formed product 1 described above. In the conventional forming method shown in Figure 2, first, the portion 102 of the blank 100 that will become the top plate portion 2 (see Figure 1A) is sandwiched between the punch 200 and the pad 202. In this state, the portions 104 of the blank 100 that will become the second wall portion 4 (see Figure 1A) and the second flange portion 6 (see Figure 1A) are pushed towards the punch 200 by the die 204.

[0023] At this time, the portion 106 of the blank 100 that will become the first wall portion 3 (see Figure 1A) and the first flange portion 5 (see Figure 1A) is not in contact with the die 204, and deformation is not sufficiently suppressed. As a result, as shown in Figure 2, the portion 106 of the blank 100 that will become the first wall portion 3 and the first flange portion 5 is prone to bending.

[0024] Subsequently, the die 204 is pushed further in, completing the molding of the press-formed product 1 (see Figure 1A). At this time, the deflection of the above-mentioned portion 106 of the blank 100 may remain as wrinkles in the first wall portion 3 and the first flange 5 of the press-formed product 1. For this reason, it is necessary to suppress the occurrence of deflection in the blank 100 during press molding. In particular, wrinkles are likely to occur in the first wall portion 3 and the first flange 5 of the curved portion 7 of the press-formed product 1.

[0025] (Embodiment) The press apparatus, method for manufacturing a press-formed product, and mold according to an embodiment of the present invention enable the formation of a press-formed product, such as the press-formed product 1 described above, in a single step while suppressing the occurrence of deflection. A press apparatus according to one embodiment of the present invention will be described below with reference to the drawings. The press apparatus and mold according to the embodiment of the present invention described below may be used for cold working on a blank, or for hot stamping on a blank.

[0026] (Pressing device) The following describes in detail an embodiment of the present invention of a press apparatus. Figure 3 is a schematic diagram showing a cross-section of a press apparatus according to one embodiment of the present invention. The cross-section of the press apparatus refers to a cross-section perpendicular to the length direction of the press-formed product 1 formed by the press apparatus.

[0027] As shown in Figure 3, the press apparatus 10 according to this embodiment comprises a first die 12, a second die 14, and a third support portion 16. The first die 12 and the second die 14 are arranged to face each other in the pressing direction X.

[0028] In the following description, the side on which the first die 12 is located relative to the second die 14 in the pressing direction X is referred to as the first die 12 side, and the side on which the second die 14 is located relative to the first die 12 in the pressing direction X is referred to as the second die 14 side. In the following description, when simply referred to as the first die 12 side, it means the first die 12 side in the pressing direction X, and when simply referred to as the second die 14 side, it means the second die 14 side in the pressing direction X. Also, in the cross-section of the press device 10, one side in the direction perpendicular to the pressing direction X is referred to as the first lateral side, and the other side as the second lateral side. In this embodiment, the first die 12 is the lower die, and the second die 14 is the upper die. Therefore, in this embodiment, the first die 12 side means the lower side, and the second die 14 side means the upper side. Also, in Figure 3, the left side of the paper corresponds to the first lateral side, and the right side of the paper corresponds to the second lateral side.

[0029] The first type 12 has a punch 20, a first holder 22, and a first support portion 24. In this embodiment, the punch 20 is supported by a bolster 18. In this embodiment, the punch 20 has a punch top surface 20a, a first punch shoulder portion 20b, a second punch shoulder portion 20c, a first punch wall surface 20d, a second punch wall surface 20e, a third punch shoulder portion 20f, a fourth punch shoulder portion 20g, a first punch support surface 20h, and a second punch support surface 20i. The first punch shoulder portion 20b and the second punch shoulder portion 20c have a shape that is convex toward the outside of the punch 20, while the third punch shoulder portion 20f and the fourth punch shoulder portion 20g have a shape that is concave toward the inside of the punch 20.

[0030] The punch top surface 20a is the part for forming the top plate portion 2 of the press-formed product 1, and is provided to face the second die 14 side. The first punch shoulder portion 20b is provided on the first lateral edge of the punch top surface 20a, and the second punch shoulder portion 20c is provided on the second lateral edge of the punch top surface 20a.

[0031] The first punch wall surface 20d is provided so as to extend from the first punch shoulder portion 20b toward the first die 12, and the second punch wall surface 20e is provided so as to extend from the second punch shoulder portion 20c toward the first die 12. In this embodiment, the first punch wall surface 20d and the second punch wall surface 20e are inclined with respect to the press direction X such that the distance between them increases toward the first die 12. In the press direction X, the second punch wall surface 20e is longer than the first punch wall surface 20d.

[0032] The third punch shoulder portion 20f is provided on the edge of the first punch wall surface 20d on the first die 12 side, and the fourth punch shoulder portion 20g is provided on the edge of the second punch wall surface 20e on the first die 12 side. In this embodiment, the fourth punch shoulder portion 20g is provided on the first die 12 side than the third punch shoulder portion 20f.

[0033] The first punch support surface 20h is provided so as to extend a first lateral side with respect to the edge of the first punch wall surface 20d on the first die 12 side, and the second punch support surface 20i is provided so as to extend a second lateral side with respect to the edge of the second punch wall surface 20e on the first die 12 side. In this embodiment, the first punch support surface 20h is provided so as to extend a first lateral side from the third punch shoulder portion 20f, and the second punch support surface 20i is provided so as to extend a second lateral side from the fourth punch shoulder portion 20g. In this embodiment, the first punch support surface 20h is provided on the second die 14 side than the second punch support surface 20i.

[0034] Figure 4 is a schematic diagram of the punch 20 as seen from the second die 14 side. As described above, the press apparatus 10 according to this embodiment is an apparatus for manufacturing a press-formed product 1 having a curved portion 7 (see Figures 1A and 1B). For this reason, as shown in Figure 4, the top surface of the punch 20a is configured to have a curved portion 21 that curves in an arc shape when viewed from the second die 14 side, corresponding to the shape of the top plate portion 2 of the press-formed product 1. Similarly, the first punch shoulder portion 20b, the second punch shoulder portion 20c, the first punch wall surface 20d, the second punch wall surface 20e, the third punch shoulder portion 20f, and the fourth punch shoulder portion 20g are also configured to have curved portions that curve in an arc shape when viewed from the second die 14 side, corresponding to the shape of the press-formed product 1. In this embodiment, the punch top surface 20a, the first punch shoulder portion 20b, the second punch shoulder portion 20c, the first punch wall surface 20d, the second punch wall surface 20e, the third punch shoulder portion 20f, and the fourth punch shoulder portion 20g are each formed to curve in the width direction of the punch top surface 20a when viewed from the second die 14 side. The width direction of the punch top surface 20a is the direction perpendicular to the pressing direction X in the cross-section of the press device 10 shown in Figure 3.

[0035] As shown in Figure 3, the first holder 22 is positioned first laterally to the first punch wall surface 20d. In this embodiment, the first holder 22 is positioned first laterally to the first punch support surface 20h. The first support portion 24 supports the first holder 22 from the first die 12 side. The first support portion 24 is provided to be able to move back and forth in the press direction X relative to the punch 20. In this embodiment, the first support portion 24 is supported by the third support portion 16. Specifically, the third support portion 16 elastically supports the first support portion 24 from the first die 12 side so that the first support portion 24 can move back and forth in the press direction X relative to the punch 20.

[0036] The third support portion 16 only needs to be configured to elastically support the first support portion 24, and for example, the third support portion 16 can be configured in the same way as a hydraulic support device (e.g., die cushion) of a known press device. In this embodiment, elastic support means supporting the object to be supported while applying an elastic force. Therefore, in this embodiment, the third support portion 16 supports the first support portion 24 while applying an elastic force to the first support portion 24.

[0037] In this embodiment, the second type 14 includes a die 40, a second holder 42, a second support portion 44, a pair of bottoming blocks 46, a pair of bottoming blocks 48, a pad 50, and a fourth support portion 52. In this embodiment, the bottoming blocks 46 and 48 function as regulating portions.

[0038] In this embodiment, the die 40 is fixed to a slide (not shown). In this embodiment, the slide can be moved in the pressing direction X by a drive mechanism (not shown) provided in the press device 10. This allows the die 40 to be moved in the pressing direction X.

[0039] In this embodiment, the die 40 has a first die shoulder 40a, a second die shoulder 40b, a first die wall surface 40c, a second die wall surface 40d, a third die shoulder 40e, a fourth die shoulder 40f, a first die support surface 40g, and a second die support surface 40h. The first die shoulder 40a and the second die shoulder 40b have a concave shape toward the inside of the die 40, while the third die shoulder 40e and the fourth die shoulder 40f have a convex shape toward the outside of the die 40.

[0040] The first die shoulder 40a is provided to correspond to the first punch shoulder 20b, and the second die shoulder 40b is provided to correspond to the second punch shoulder 20c. Specifically, as shown in Figure 9 described later, the die shoulders 40a and 40b are provided to face the punch shoulders 20b and 20c, respectively, when the die 40 reaches its bottom dead center.

[0041] As shown in Figure 3, the first die wall surface 40c is provided to correspond to the first punch wall surface 20d, and the second die wall surface 40d is provided to correspond to the second punch wall surface 20e. Specifically, as shown in Figure 9 described later, the die walls 40c and 40d are provided to face the punch walls 20d and 20e, respectively, when the die 40 reaches the bottom dead center. In this embodiment, the first die wall surface 40c and the second die wall surface 40d are inclined with respect to the press direction X such that the distance between them increases towards the first die 12 side. In the press direction X, the second die wall surface 40d is longer than the first die wall surface 40c.

[0042] As shown in Figure 3, the third die shoulder 40e is provided on the edge of the first die wall 40c on the first die 12 side, and the fourth die shoulder 40f is provided on the edge of the second die wall 40d on the first die 12 side. The fourth die shoulder 40f is provided on the first die 12 side than the third die shoulder 40e. In this embodiment, the third die shoulder 40e is provided to correspond to the third punch shoulder 20f, and the fourth die shoulder 40f is provided to correspond to the fourth punch shoulder 20g. Specifically, as shown in Figure 9, which will be described later, the die shoulders 40e and 40f are provided to face the punch shoulders 20f and 20g, respectively, when the die 40 reaches the bottom dead center.

[0043] In addition, similar to the first punch shoulder portion 20b, the second punch shoulder portion 20c, the first punch wall surface 20d, the second punch wall surface 20e, the third punch shoulder portion 20f, and the fourth punch shoulder portion 20g, the first die shoulder portion 40a, the second die shoulder portion 40b, the first die wall surface 40c, the second die wall surface 40d, the third die shoulder portion 40e, and the fourth die shoulder portion 40f are configured to have a curved portion that curves in an arc shape when viewed from the first die 12 side, corresponding to the shape of the press-formed product 1. In this embodiment, the first die shoulder portion 40a, the second die shoulder portion 40b, the first die wall surface 40c, the second die wall surface 40d, the third die shoulder portion 40e, and the fourth die shoulder portion 40f are each formed to curve in the width direction of the punch top surface 20a of the first die 12 when viewed from the first die 12 side. As mentioned above, the width direction of the punch top surface 20a is perpendicular to the pressing direction X in the cross-section of the press device 10 shown in Figure 3.

[0044] As shown in Figure 3, the first die support surface 40g is provided so as to extend from the third die shoulder portion 40e to the first lateral side, and the second die support surface 40h is provided so as to extend from the fourth die shoulder portion 40f to the second lateral side. In this embodiment, the first die support surface 40g is provided so as to correspond to the first punch support surface 20h, and the second die support surface 40h is provided so as to correspond to the second punch support surface 20i. Specifically, as shown in Figure 9 described later, the die support surfaces 40g and 40h are provided so as to face the punch support surfaces 20h and 20i, respectively, when the die 40 reaches the bottom dead center. In this embodiment, the first die support surface 40g is provided on the second die 14 side than the second die support surface 40h.

[0045] The second holder 42 is positioned to face the first holder 22 on a first lateral side of the third die shoulder portion 40e. In this embodiment, the second holder 42 is provided on a first lateral side of the first die support surface 40g.

[0046] The second support portion 44 supports the second holder 42 so that the second holder 42 can move back and forth in the pressing direction X relative to the die 40. More specifically, the second support portion 44 is configured to elastically support the second holder 42 from the second die 14 side. Furthermore, the second support portion 44 is connected to the die 40 so as to move relative to the punch 20 in conjunction with the relative movement of the die 40 with respect to the punch 20 in the pressing direction X.

[0047] In this embodiment, the second support portion 44 is configured to be expandable and contractible in the pressing direction X, for example. The second support portion 44 can be configured using, for example, an elastic member such as a coil spring, a fluid spring such as a gas spring, or a hydraulic mechanism such as an oil damper. Although a detailed explanation is omitted, the second support portion 44 may be directly connected to the die 40, or it may be indirectly connected to the die 40 via a die holder (not shown). Furthermore, the second support portion 44 itself does not have to be elastically deformable. In other words, the second support portion 44 does not have to be configured to be expandable and contractible in the pressing direction X. In this case, the second support portion 44 may be provided so as to be able to move back and forth in the pressing direction X relative to the die 40, and may be elastically supported by a known hydraulic support device of a press device (for example, an inner cushion) so as to be able to elastically support the second holder 42 from the second die 14 side.

[0048] A pair of bottomed blocks 46 are fixed to the second holder 42 on the second die 14 side. A pair of bottomed blocks 48 are provided on the second die 14 side relative to the pair of bottomed blocks 46. In this embodiment, the pair of bottomed blocks 48 are fixed to the first die 12 side of the die 40 so as to face the pair of bottomed blocks 46 in the pressing direction X.

[0049] In this embodiment, as shown in Figure 8, which will be described later, the movement of the second holder 42 in the pressing direction X is restricted by the contact between the pair of bottoming blocks 46 and the pair of bottoming blocks 48. Specifically, the second holder 42 is restricted from being pushed toward the second mold 14 side relative to the die 40.

[0050] In this embodiment, when the pushing of the second holder 42 toward the second mold 14 toward the die 40 is not restricted by the bottoming blocks 46 and 48, the load required to push the first holder 22 toward the first mold 12 toward the punch 20 (first load) is greater than the load required to push the second holder 42 toward the second mold 14 toward the die 40 (second load). In this embodiment, the elastic forces of the second support portion 44 and the third support portion 16 are adjusted so that the first load is greater than the second load. Note that, as described above, when the second support portion 44 is elastically supported by a hydraulic support device (for example, an inner cushion), the elastic forces of the support device and the third support portion 16 are adjusted so that the first load is greater than the second load.

[0051] As shown in Figure 3, the pad 50 is positioned to face the top surface 20a of the punch in the pressing direction X. The fourth support portion 52 supports the pad 50 so that it can move back and forth relative to the die 40 in the pressing direction X. More specifically, the fourth support portion 52 is configured to elastically support the pad 50 from the second die 14 side. The fourth support portion 52 is also connected to the die 40 so as to move relative to the punch 20 in conjunction with the relative movement of the die 40 relative to the punch 20 in the pressing direction X.

[0052] In this embodiment, the fourth support portion 52 may be configured to be expandable and contractible in the pressing direction X, similar to the second support portion 44, or it may be supported on the die 40 so as to be able to move back and forth in the pressing direction X. The fourth support portion 52 may be configured using, for example, an elastic member such as a coil spring, a fluid spring such as a gas spring, or a hydraulic mechanism such as an oil damper, similar to the second support portion 44. The fourth support portion 52 may also be elastically supported by, for example, a hydraulic support device (e.g., an inner cushion) of a known press device, similar to the second support portion 44. The fourth support portion 52 may be directly connected to the die 40, similar to the second support portion 44, or it may be indirectly connected to the die 40 via a die holder (not shown).

[0053] In this embodiment, in the initial position of the press device 10 (the state shown in Figure 3), the distance L between the bottoming block 46 and the bottoming block 48 in the pressing direction X is equal to the distance P between the first punch support surface 20h and the second punch support surface 20i in the pressing direction X. In the initial position of the press device 10, the position of the punch top surface 20a and the position of the face of the first holder 22 on the second die 14 side are equal in the pressing direction X. In the initial position of the press device 10, the position of the end of the fourth die shoulder portion 40f on the first die 12 side (position of the second die support surface 40h), the position of the face of the second holder 42 on the first die 12 side, and the position of the face of the pad 50 on the first die 12 side are equal to each other in the pressing direction X.

[0054] (Method of manufacturing molded products) Next, a method for manufacturing the press-formed product 1 using the press apparatus 10 described above will be explained. Figures 5 to 9 are diagrams illustrating the method for manufacturing the press-formed product according to this embodiment.

[0055] When manufacturing a press-formed product 1 using the press device 10, as shown in Figure 5, first, a plate-shaped blank 100, which will be the material for the press-formed product 1, is placed on the top surface 20a of the punch 20. In this embodiment, as described above, in the initial position of the press device 10, the position of the face of the first holder 22 on the second die 14 side is equal to the position of the top surface 20a of the punch in the pressing direction X. Therefore, in this embodiment, the blank 100 is supported by the top surface 20a of the punch and the first holder 22. In this embodiment, the blank 100 is a metal plate such as a steel plate. The thickness of the blank 100 is, for example, 0.8 to 4.0 mm.

[0056] Next, as shown in Figure 6, the die 40 is moved relative to the first die 12 side, and the blank 100 is sandwiched between the punch top surface 20a and the first holder 22, and the pad 50 and the second holder 42. In this embodiment, in the initial position of the press device 10, in the pressing direction X, the position of the second die support surface 40h is equal to the position of the face of the second holder 42 on the first die 12 side and the position of the face of the pad 50 on the first die 12 side. Therefore, in the state shown in Figure 6, the blank 100 is also in contact with the second die support surface 40h.

[0057] Next, as shown in Figure 7, the die 40 is moved further toward the first mold 12, and the blank 100 is pushed toward the first mold 12 by the fourth die shoulder 40f. This initiates the molding of the second wall 4 (see Figure 1A) and the second flange 6 (see Figure 1A).

[0058] As described above, the fourth support portion 52 supports the pad 50 so that the pad 50 can move back and forth in the pressing direction X relative to the die 40. In this embodiment, as the die 40 moves relative to the first die 12, the fourth support portion 52 retracts, and the pad 50 is pushed toward the second die 14 relative to the die 40.

[0059] Furthermore, as described above, the second support portion 44 supports the second holder 42 so that the second holder 42 can move back and forth in the pressing direction X relative to the die 40. Also, when the bottoming block 46 and the bottoming block 48 are not in contact, the load required to push the first holder 22 toward the first die 12 relative to the punch 20 is greater than the load required to push the second holder 42 toward the second die 14 relative to the die 40. With these configurations, in this embodiment, as the die 40 moves relative to the first die 12, the second support portion 44 contracts, and the second holder 42 is pushed toward the second die 14 relative to the die 40.

[0060] As shown in Figure 8, the die 40 is moved further toward the first die 12 until the bottoming block 46 and bottoming block 48 come into contact, thereby advancing the forming of the second wall portion 4 (see Figure 1A) and the second flange 6 (see Figure 1A). The bottoming block 46 and bottoming block 48 come into contact when the second holder 42 is pushed relative to the die 40 by a predetermined amount (in this embodiment, distance L: see Figure 3) toward the second die 14. In this embodiment, the bottoming block 46 and bottoming block 48 come into contact when, in the pressing direction X, the second holder 42 is positioned to correspond to the third die shoulder portion 40e and the first die support surface 40g. More specifically, in this embodiment, the bottoming block 46 and bottoming block 48 come into contact when, in the pressing direction X, the position of the face of the second holder 42 on the first die 12 side is equal to the position of the end of the third die shoulder portion 40e on the first die 12 side and the position of the first die support surface 40g. This restricts the first holder 22 from being pushed relative to the second mold 14 side relative to the die 40.

[0061] As shown in Figure 9, with the pushing of the second holder 42 toward the second mold 14 relative to the die 40 restricted, the die 40 is further moved toward the first mold 12 relative to the punch 20. This causes the fourth die shoulder 40f to be pushed further toward the first mold 12. At the same time, the first holder 22 is pushed toward the first mold 12 by the second holder 42 via the blank 100, and the blank 100 is pushed toward the first mold 12 by the third die shoulder 40e. As a result, the formation of the second wall 4 (see Figure 1A) and the second flange 6 (see Figure 1A) progresses, as well as the formation of the first wall 3 (see Figure 1A) and the first flange 5 (see Figure 1A). The formation of the press-formed product 1 is completed when the die 40 reaches its bottom dead center. In this embodiment, at the bottom dead center of the die 40, the first lateral end (first flange 5) of the blank 100 is sandwiched between the first holder 22 and the first punch support surface 20h, and the second holder 42 and the first die support surface 40g. The second lateral end (second flange 6) of the blank 100 is sandwiched between the second punch support surface 20i and the second die support surface 40h. In this embodiment, the press-formed product 1 is formed such that one edge 2a (see Figure 1A) of the top plate portion 2 is located on the first lateral side of the punch top surface 20a, and the other edge 2b (see Figure 1A) is located on the second lateral side of the punch top surface 20a.

[0062] In this embodiment, as shown in Figure 9, the second holder 42 is supported by the second support portion 44 so as not to protrude beyond the first punch support surface 20h toward the first die 12. Preferably, the second holder 42 is supported by the second support portion 44 so as not to protrude beyond the end of the third die shoulder portion 40e toward the first die 12 (first die support surface 40g). This allows the first flange 5 to be formed properly. The same applies to the embodiments described later. In this embodiment, when the die 40 reaches the bottom dead center, the amount of indentation of the second holder 42 toward the second die 14 (distance L shown in Figure 3) is adjusted so that the surface of the second holder 42 toward the first die 12 does not protrude beyond the first punch support surface 20h toward the first die 12. Preferably, when the die 40 reaches the bottom dead center, the amount of the second holder 42 pushed toward the second die 14 is adjusted so that the surface of the second holder 42 on the first die 12 side does not protrude toward the first die 12 side beyond the end of the third die shoulder portion 40e on the first die 12 side (first die support surface 40g). The same applies to the embodiments described later. Specifically in this embodiment, as described above, in the initial position of the press device 10 (the state shown in Figure 3), the bottoming block 46 and the bottoming block 48 are provided such that the distance L between the bottoming block 46 and the bottoming block 48 in the pressing direction X is equal to the distance P between the first punch support surface 20h and the second punch support surface 20i in the pressing direction X.

[0063] (effect) In this embodiment, when the die 40 is pushed towards the first mold 12, the second holder 42 can be pushed relative to the die 40 towards the second mold 14. This allows the forming of the second lateral portion of the blank 100, namely the second wall portion 4 and the second flange 6, to proceed without proceeding with the forming of the first lateral portion of the blank 100, namely the first wall portion 3 and the first flange 5. As a result, it becomes possible to form a press-formed product 1 with a pair of wall portions 3 and 4 of different heights in a single process.

[0064] Furthermore, as described above, the second holder 42 can be pushed towards the second die 14, so that at the initial position of the press device 10, the position of the surface of the second holder 42 on the first die 12 side and the position of the end of the fourth die shoulder 40f on the first die 12 side (the position of the second die support surface 40h) can be brought sufficiently close in the pressing direction X. This makes it possible to bring the second holder 42 into contact with the blank 100 at the start of molding by the fourth die shoulder 40f or shortly after the start of molding. In this case, when the second lateral portion of the blank 100 (the portion that becomes the second wall 4 and the second flange 6) is pressed by the fourth die shoulder 40f, deflection of the first lateral portion of the blank 100 (the portion that becomes the first wall 3 and the first flange 5) can be suppressed. In particular, in this embodiment, the molding of the second wall portion 4 by the fourth die shoulder portion 40f can be carried out while the first lateral portion of the blank 100 is sandwiched between the first holder 22 and the second holder 42. This makes it possible to sufficiently suppress the occurrence of deflection in the first lateral portion of the blank 100.

[0065] Furthermore, by sandwiching the first lateral portion of the blank 100 between the first holder 22 and the second holder 42, it is possible to sufficiently suppress the first lateral portion of the blank 100 from being dragged to the second lateral portion when molding is being performed on the second lateral portion of the blank 100. This stabilizes the position of the blank 100 and allows for proper molding of the press-formed product 1.

[0066] In this embodiment, when the second holder 42 is positioned in the pressing direction X to correspond to the third die shoulder 40e, the bottoming block 46 and the bottoming block 48 come into contact, restricting the second holder 42 from being pushed toward the second die 14 relative to the die 40. In other words, the second holder 42 is pushed toward the second die 14 relative to the die 40 until it is positioned to correspond to the third die shoulder 40e. In this case, the first holder 22 and the second holder 42 prevent the blank 100 from being pushed toward the first die 12 relative to the blank 100 before the third die shoulder 40e comes into contact with the blank 100. This prevents a large tension from being applied to the portion of the blank 100 that will become the first wall portion 3 (see Figure 1A) (the portion between the holders 22, 42 and the punch top surface 20a) before the third die shoulder 40e comes into contact with the blank 100. In other words, it is possible to prevent the formation of the first wall portion 3 by the third die shoulder portion 40e from starting while a large tension is applied to the portion of the blank 100 that will become the first wall portion 3. As a result, the occurrence of cracks in the first wall portion 3 can be sufficiently suppressed.

[0067] Furthermore, when moving the die 40 towards the first die 12 from the state shown in Figure 6, it is also possible to push the first holder 22 toward the first die 12 relative to the punch 20, and then push the second holder 42 toward the second die 14 relative to the die 40. Alternatively, it is also possible to push the first holder 22 toward the first die 12 relative to the punch 20 at the same time as pushing the second holder 42 toward the second die 14 relative to the die 40.

[0068] However, in these cases, a large tension is applied to the portion of the blank 100 that will become the first wall portion 3 before the third die shoulder portion 40e contacts the blank 100. In other words, the forming of the first wall portion 3 by the third die shoulder portion 40e begins with a large tension applied to the portion of the blank 100 that will become the first wall portion 3. This makes the first wall portion 3 more prone to cracking.

[0069] Furthermore, if the first holder 22 is pushed significantly toward the first die 12 relative to the punch 20 before the third die shoulder 40e contacts the blank 100, deflection may occur in the first wall 3 and first flange 5 of the curved portion 7 of the blank 100. This deflection may also remain as wrinkles in the press-formed product 1.

[0070] Therefore, in this embodiment, when the pushing of the second holder 42 toward the second mold 14 toward the die 40 is not restricted, the load required to push the first holder 22 toward the first mold 12 toward the punch 20 is made greater than the load required to push the second holder 42 toward the second mold 14 toward the die 40. As a result, from the time molding of the blank 100 is started until the pushing of the second holder 42 toward the second mold 14 toward the die 40 is restricted, the first holder 22 is prevented from being pushed toward the first mold 12 toward the punch 20. In this case, it is possible to sufficiently prevent large tension from being applied to the portion of the blank 100 that will become the first wall portion 3 and the first flange 5 before the third die shoulder portion 40e contacts the blank 100. As a result, it is possible to sufficiently suppress the occurrence of cracks in the first wall portion 3. In addition, it is possible to sufficiently suppress the occurrence of deflection in the portion of the blank 100 that will become the first wall portion 3 and the first flange 5 of the curved portion 7. As a result, the occurrence of wrinkles in the first wall portion 3 and the first flange 5 of the press-formed product 1 can be sufficiently suppressed. The load required to push the first holder 22 toward the first die 12 relative to the punch 20 is preferably 1.5 times or more, and more preferably 2.0 times or more, than the load required to push the second holder 42 toward the second die 14 relative to the die 40.

[0071] (modified version) In the embodiment described above, as shown in Figure 6, the initial positions of the parts of the press device 10 are adjusted so that, at the start of forming the blank 100, the blank 100 is sandwiched between the punch top surface 20a and the first holder 22, and between the pad 50 and the second holder 42, and in contact with the second die support surface 40h. However, the initial positions of the parts of the press device are not limited to the example described above. The initial positions of the parts of the press device 10 can be adjusted so that, at the start of forming the blank 100, the blank 100 is sandwiched between at least one of the punch top surface 20a and the first holder 22, and between at least one of the pad 50 and the second holder 42.

[0072] For example, as shown in Figure 10, at the initial position of the press device 10, the surface of the first holder 22 on the second die 14 side may be located a distance H toward the first die 12 side from the punch top surface 20a. Also, although not shown in the figure, at the initial position of the press device 10, the surface of the first holder 22 on the second die 14 side may be located a distance H toward the second die 14 side from the punch top surface 20a. In these cases as well, the amount of indentation (distance L) of the second holder 42 toward the second die 14 side should be appropriately adjusted so that when the die 40 reaches the bottom dead center, the surface of the second holder 42 on the first die 12 side does not protrude toward the first die 12 side from the first punch support surface 20h. For example, at the initial position of the press device 10 shown in Figure 10, bottoming blocks 46 and 48 are provided such that distance L is equal to the sum of distances P and H. In other words, bottom blocks 46 and 48 are provided such that distances L, P, and H satisfy the relationship given by "L = P + H". As shown in Figure 10, if the surface of the first holder 22 on the second die 14 side is located closer to the first die 12 than the punch top surface 20a, distance H is treated as a positive value in the above relationship. Conversely, if the surface of the first holder 22 on the second die 14 side is located closer to the second die 14 than the punch top surface 20a, distance H is treated as a negative value in the above relationship. The same applies to the relationship described later. The distance H is preferably 0.4 times or less the length of the first die wall surface 40c in the press direction X (length of the first wall portion 3 in the thickness direction of the top plate portion 2), more preferably 0.2 times or less, and even more preferably 0.05 times or less. The same applies to the mold described later.

[0073] Furthermore, for example, as shown in Figure 11, at the initial position of the press device 10, the surface of the second holder 42 on the first die 12 side may be located a distance D toward the first die 12 side than the fourth die shoulder portion 40f (second die support surface 40h). In the example shown in Figure 11, the positions of the surface of the pad 50 on the first die 12 side and the second die support surface 40h in the pressing direction X are the same, but at the initial position of the press device 10, the surface of the pad 50 on the first die 12 side may be located a distance D toward the first die 12 side than the fourth die shoulder portion 40f (second die support surface 40h), similar to the second holder 42. Also, although not shown, at the initial position of the press device 10, the surface of the second holder 42 on the first die 12 side may be located a distance D toward the second die 14 side than the end of the fourth die shoulder portion 40f on the first die 12 side (second die support surface 40h). Furthermore, at the initial position of the press device 10, the surface of the pad 50 on the first die 12 side may be positioned at a distance D toward the second die 14 side from the end of the fourth die shoulder 40f on the first die 12 side (second die support surface 40h), similar to the second holder 42. In these cases as well, the amount of indentation (distance L) of the second holder 42 toward the second die 14 side should be appropriately adjusted so that the second holder 42 does not protrude toward the first die 12 side beyond the first punch support surface 20h when the die 40 reaches the bottom dead center. For example, at the initial position of the press device 10, bottoming blocks 46 and 48 are provided such that distance L is equal to the sum of distances P, H, and D. That is, bottoming blocks 46 and 48 are provided such that distances L, P, H, and D satisfy the relationship given by "L = P + H + D". As shown in Figure 11, if the side of the second holder 42 facing the first mold 12 is located closer to the first mold 12 than the fourth die shoulder portion 40f (second die support surface 40h), then the distance D in the above relational expression is treated as a positive value. Conversely, if the side of the second holder 42 facing the first mold 12 is located closer to the second mold 14 than the end of the fourth die shoulder portion 40f facing the first mold 12 (second die support surface 40h), then the distance D in the above relational expression is treated as a negative value. The same applies to the mold described later.

[0074] In the examples shown in Figures 10 and 11, tension is applied to the portion of the blank 100 between the second holder 42 and the punch top surface 20a before the third die shoulder 40e contacts the blank 100. However, even in these embodiments, the first holder 22 is prevented from being pushed toward the first die 12 relative to the punch 20 from the time forming on the blank 100 begins until the pushing of the second holder 42 toward the second die 14 relative to the die 40 is restricted. Therefore, by appropriately setting the distance H, it is possible to sufficiently prevent large tension from being applied to the portion of the blank 100 between the second holder 42 and the punch top surface 20a before the third die shoulder 40e contacts the blank 100. This makes it possible to sufficiently suppress the occurrence of cracks and wrinkles in the press-formed product 1.

[0075] As shown in Figure 12, a distance block 54 may be provided between the first holder 22 and the second holder 42. The dimensions of the distance block 54 are set, for example, so that the gap between the first holder 22 and the second holder 42 is approximately 1.5 to 3.0 times the thickness of the blank 100. The same applies to the mold described later.

[0076] When performing hot stamping using the press device 10, the distance block 54 can suppress heat loss from the blank 100 via the holders 22 and 42, and the temperature of the blank 100 can be kept high until molding by the third die shoulder 40e begins.

[0077] Furthermore, when the distance block 54 is provided, the force with which the holders 22 and 42 hold the blank 100 is reduced compared to when the distance block 54 is not provided. However, by appropriately adjusting the dimensions of the distance block 54, deflection can be sufficiently suppressed. In addition, the contact between the holders 22 and 42 and the blank 100 sufficiently prevents the blank 100 from being dragged to the second lateral side when molding is being performed on the second lateral side of the blank 100.

[0078] In the above embodiment, the top plate portion 2 of the press-formed product 1 is formed by the punch top surface 20a and the pad 50, but the pad 50 is not required. For example, as shown in Figure 13, a support surface 40i may be formed to connect the first die shoulder portion 40a and the second die shoulder portion 40b, and the top plate portion 2 may be formed by the punch top surface 20a and the support surface 40i. The same applies to the mold described later.

[0079] In the press-formed product 1 described above, the first wall portion 3, which is low in height, is located on the inside of the curve of the curved portion 7. However, as shown in the press-formed product 1a in Figure 14, the first wall portion 3, which is low in height, may be located on the outside of the curve of the curved portion 7. Also, as shown in the press-formed product 1b in Figure 15, for example, multiple curved portions 7a and 7b that are curved in different directions in a plan view may be provided. The configuration of each part of the press device 10 is appropriately changed according to the shape of the press-formed products 1a and 1b. The same applies to the mold described later.

[0080] Furthermore, the punch 20 may be configured to form a press-formed product having a curved portion that curves when viewed from the side. Figure 16 is a schematic diagram of a modified punch 20 viewed from the second side. As shown in Figure 16, the punch 20 may have a plurality of curved portions 21a, 21b that curve when viewed from a direction perpendicular to the press direction X. The other components of the press device 10 may be appropriately changed according to the shape of the punch 20 (press-formed product). The press device 10 may be configured to form a press-formed product that curves when viewed from the press direction X and also curves when viewed from a direction perpendicular to the press direction X. The same applies to the mold described later.

[0081] Furthermore, while the press apparatus according to the embodiment of the present invention can be suitably used to manufacture press-formed products having curved sections, which are particularly prone to wrinkles, it can also be suitably used to manufacture straight press-formed products that do not have curved sections. In this case as well, press-formed products with a pair of wall sections of different heights can be formed in a single process while suppressing the occurrence of deflection.

[0082] Figure 17 shows a mold 11 according to one embodiment of the present invention. The mold 11 according to this embodiment comprises a first mold 12a and a second mold 14. The second mold 14 is configured in the same way as in the embodiment described above, so its description is omitted.

[0083] The first type 12a differs from the first type 12 described above in that it has a first support portion 24a instead of the first support portion 24. The first support portion 24a differs from the first support portion 24 described above in that it elastically supports the first holder 22 so that the first holder 22 can move back and forth in the pressing direction X relative to the punch 20, and that it is supported by the bolster 18 instead of the third support portion 16 (see Figure 3).

[0084] In this embodiment, the first support portion 24a may be configured to be expandable and contractible in the pressing direction X, for example, or it may be supported by the bolster 18 so as to be able to move back and forth in the pressing direction X. The first support portion 24a can be configured using, for example, an elastic member such as a coil spring, a fluid spring such as a gas spring, or a hydraulic mechanism such as an oil damper.

[0085] In this embodiment, when the pushing of the second holder 42 toward the second die 14 toward the die 40 is not restricted, the elastic forces of the first support portion 24a and the second support portion 44 are adjusted so that the load required to push the first holder 22 toward the first die 12a toward the punch 20 (first load) is greater than the load required to push the second holder 42 toward the second die 14 toward the die 40 (second load). If the second support portion 44 is elastically supported by a hydraulic support device (for example, an inner cushion), the elastic forces of the first support portion 24a and the support device are adjusted so that the first load is greater than the second load. The same applies to the embodiments described later.

[0086] In the mold 11 described above, the first support portion 24a is supported by the bolster 18, but the first support portion only needs to support the first holder so that the first holder can move back and forth in the pressing direction relative to the punch. For example, as shown in the mold 11a in Figure 18, the first support portion 24a may be supported by a part of the punch 23 instead of the bolster 18. Note that the punch 23 shown in Figure 18 has the same configuration as the punch 20 described above, except that it is configured to support the first support portion 24a.

[0087] The above-described explanation of the method for manufacturing a press-formed product 1 using the press device 10 can be replaced with the explanation of the method for manufacturing a press-formed product 1 using a die 11 by substituting the first mold 12 with the first mold 12a. Furthermore, the above-described explanation of the method for manufacturing a press-formed product 1 using the press device 10 can be replaced with the explanation of the method for manufacturing a press-formed product 1 using a die 11a by substituting the first mold 12 with the first mold 12b and the punch 20 with the punch 23. Therefore, the same effects can be obtained when manufacturing a press-formed product using die 11 and 11a as when manufacturing a press-formed product using the press device 10.

[0088] Although a detailed explanation is omitted, in the press apparatus 10 or molds 11, 11a described above, a holder may be provided so as to face the second die support surface 40h in the pressing direction X. In this case, the press-formed product can be formed with the second lateral portion of the blank 100 sandwiched between the second die support surface 40h and the holder.

[0089] In the above-described embodiment, a case was described in which a press-formed product having a pair of flanges 5 and 6 is manufactured, but one or both of the flanges 5 and 6 may be omitted. For example, the press device 10 or molds 11, 11a may be configured to draw out at least one of the first lateral portion and the second lateral portion of the blank 100 before the die 40 reaches the bottom dead center. Also, for example, the press device 10 or molds 11, 11a may not have to provide the first punch support surface 20h, the second punch support surface 20i, the first die support surface 40g, and the second die support surface 40h.

[0090] In the above-described embodiment, the restricting portion is formed by the bottom block 46 and the bottom block 48, but the configuration of the restricting portion is not limited to the above example. For example, the second support portion 44 itself may be provided with a member (restricting portion) that restricts the amount of expansion and contraction of the second support portion 44, and by restricting the amount of expansion and contraction of the second support portion 44, the pushing of the second holder 42 toward the second mold 14 toward the die 40 may be restricted. [Industrial applicability]

[0091] According to the present invention, a press-formed product having a pair of wall sections of different heights can be formed in a single process while suppressing the occurrence of deflection. [Explanation of Symbols]

[0092] 1,1a,1b Press-formed product 2. Top panel 3 1st wall 4 Second wall 5. First flange 6. Second flange 7. Curved section 10 Pressing device 11,11a Mold 12,12a,12b Type 1 14 Type 2 16 Third support part 20,23 punches 22 First holder 24,24a 1st support part 40 Dies 42 Second holder 44 Second support part 46, 48 Bottomed block (regulating section) 50 pads

Claims

1. A first mold having a punch, a first holder, and a first support portion that supports the first holder and is movable in the pressing direction relative to the punch, A die, a second holder, a second support portion that supports the second holder so that the second holder can move back and forth relative to the die in the pressing direction, and a restricting portion that restricts the movement of the second holder in the pressing direction, and a second die facing the first die in the pressing direction, It comprises a third support portion that supports the first support portion, In the pressing direction, the side on which the first die is located as seen from the second die is defined as the first die side, and the side on which the second die is located as seen from the first die is defined as the second die side, and one side in the direction perpendicular to the pressing direction is defined as the first lateral side, and the other side as the second lateral side. The punch has a punch top surface facing the second die side, a first punch shoulder provided on the first lateral edge of the punch top surface, a second punch shoulder provided on the second lateral edge of the punch top surface, a first punch wall surface extending from the first punch shoulder towards the first die side, and a second punch wall surface extending from the second punch shoulder towards the first die side. The first holder is positioned on the first lateral side of the first punch wall surface, The first support portion supports the first holder from the first mold side, The die has a first die shoulder corresponding to the first punch shoulder, a second die shoulder corresponding to the second punch shoulder, a first die wall corresponding to the first punch wall, a second die wall corresponding to the second punch wall, a third die shoulder provided on the first die side edge of the first die wall, and a fourth die shoulder provided on the first die side edge of the second die wall. The fourth die shoulder portion is provided on the first die side of the third die shoulder portion, The second holder is positioned to face the first holder on the first lateral side of the third die shoulder, The second support portion is configured to elastically support the second holder from the second die side, and is connected to the die so as to move relative to the punch in the pressing direction in conjunction with the relative movement of the die relative to the punch. The third support portion elastically supports the first support portion from the first mold side, The restricting portion restricts the second holder from being pushed relative to the die toward the second mold when the second holder is pushed relative to the die toward the second mold by a predetermined amount. When the pushing of the second holder toward the second die relative to the die is not restricted by the restricting portion, the load required to push the first holder toward the first die relative to the punch is greater than the load required to push the second holder toward the second die relative to the die. A press device in which, while the pushing of the second holder toward the second die relative to the die is restricted by the restricting portion, the die moves toward the first die relative to the punch, thereby causing the first holder to be pushed toward the first die relative to the punch by the second holder.

2. The punch has a first punch support surface that extends to the first lateral side with respect to the edge of the first punch wall surface on the first die side, The die has a first die support surface extending from the third die shoulder to the first lateral side, The press apparatus according to claim 1, wherein the second holder is supported by the second support portion such that it does not protrude toward the first die side beyond the first punch support surface.

3. The second type is the press apparatus according to claim 1, further comprising a pad positioned opposite the top surface of the punch.

4. The press apparatus according to claim 1, wherein the top surface of the punch has a curved portion that curves when viewed from the pressing direction or the perpendicular direction.

5. When manufacturing a press-formed product having a top plate portion, a first wall portion extending from the first edge of the top plate portion in the thickness direction, and a second wall portion extending from the second edge of the top plate portion in the thickness direction and having a length in the thickness direction longer than that of the first wall portion, from a blank made of a metal sheet, With the blank held between the first and second holders, the die is moved relative to the punch toward the first die until the regulating portion restricts the second holder from being pushed toward the second die toward the die, and the blank is pushed toward the first die toward the fourth die shoulder, thereby advancing the formation of the second wall. A press apparatus according to any one of claims 1 to 4, wherein the pressing of the second holder toward the second die relative to the die is restricted by the restricting portion, the die is moved relative to the first die relative to the punch to form the second wall portion, and the first wall portion is formed by pressing the blank toward the first die relative to the punch with the second holder and the blank with the third die shoulder portion.

6. A first mold having a punch, a first holder, and a first support portion that supports the first holder so that the first holder can move back and forth in the pressing direction relative to the punch, A die, a second holder, a second support portion that supports the second holder so that the second holder can move back and forth relative to the die in the pressing direction, and a second die that has a restricting portion that restricts the movement of the second holder in the pressing direction and faces the first die in the pressing direction, In the pressing direction, the side on which the first die is located as seen from the second die is defined as the first die side, and the side on which the second die is located as seen from the first die is defined as the second die side, and one side in the direction perpendicular to the pressing direction is defined as the first lateral side, and the other side as the second lateral side. The punch has a punch top surface facing the second die side, a first punch shoulder provided on the first lateral edge of the punch top surface, a second punch shoulder provided on the second lateral edge of the punch top surface, a first punch wall surface extending from the first punch shoulder towards the first die side, and a second punch wall surface extending from the second punch shoulder towards the first die side. The first holder is positioned on the first lateral side of the first punch wall surface, The first support portion elastically supports the first holder from the first mold side, The die has a first die shoulder corresponding to the first punch shoulder, a second die shoulder corresponding to the second punch shoulder, a first die wall corresponding to the first punch wall, a second die wall corresponding to the second punch wall, a third die shoulder provided on the first die side edge of the first die wall, and a fourth die shoulder provided on the first die side edge of the second die wall. The fourth die shoulder portion is provided on the first die side of the third die shoulder portion, The second holder is positioned to face the first holder on the first lateral side of the third die shoulder, The second support portion is configured to elastically support the second holder from the second die side, and is connected to the die so as to move relative to the punch in the pressing direction in conjunction with the relative movement of the die relative to the punch. The restricting portion restricts the second holder from being pushed relative to the die toward the second mold when the second holder is pushed relative to the die toward the second mold by a predetermined amount. When the pushing of the second holder toward the second die relative to the die is not restricted by the restricting portion, the load required to push the first holder toward the first die relative to the punch is greater than the load required to push the second holder toward the second die relative to the die. A mold in which, while the pushing of the second holder toward the second mold side relative to the die is restricted by the restricting portion, the die moves toward the first mold side relative to the punch, causing the first holder to be pushed toward the first mold side relative to the punch by the second holder.

7. A method for manufacturing a press-formed product having a top plate portion, a first wall portion extending from a first edge of the top plate portion in the thickness direction of the top plate portion, and a second wall portion extending from a second edge of the top plate portion in the thickness direction and having a length in the thickness direction longer than that of the first wall portion, using a press apparatus according to any one of claims 1 to 4 or a mold according to claim 6, from a blank made of a metal sheet, With the blank held between the first and second holders, the die is moved relative to the punch toward the first die until the regulating portion restricts the second holder from being pushed toward the second die toward the die, and the blank is pushed toward the first die toward the fourth die shoulder, thereby advancing the formation of the second wall. A method for manufacturing a press-formed product, wherein the pushing of the second holder toward the second die relative to the die is restricted by the restricting portion, the die is moved relative to the first die relative to the punch to form the second wall portion, and the first wall portion is formed by pushing the first holder toward the first die relative to the punch with the second holder, while pushing the blank toward the first die with the third die shoulder portion.

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