Technical Field [000 1] The present invention relates to a manufacturing method for a hat-shaped cross-section component that has a hat-shaped cross-section. Background Art [0002] Pressed components with a hat-shaped cross-section profile (also referred to as "hat-shaped cross-section components" in the present specification), such as front side members, are known as structural members configuring automotive vehicle body framework. Such hat -shaped cross-section components are formed by perfonning press working (drawing) or the like on metal sheet materials (for example, steel sheets) (see, for example, Japanese Patent Application Laid-Open (JP-A) Nos. 2003-103306,2004-154859, and 2006-015404 ). SUMMARY OF INVENTION Technical Problem [0003] In the manufacture of hat-shaped cross-section components, sometimes a preliminarily formed component with a hat-shaped cross-section profile is formed, and secondary processing is performed on the preliminarily formed component to change the height of the preliminarily formed component and manufacture the hat-shaped cross-section component. For example, in the secondary processing, vertical walls at one side in a length direction of the preliminarily formed .component are bent and stretched to increase the height of the preliminarily formed component, and vertical walls at another side in the length direction of the preliminarily formed component are bent back to lower the height of the preliminarily formed component, thereby manufacturing the hat -shaped cross-section component. [0004] However, in the secondary processing, for example, there is a possibility of cracking or the like occurring at a boundary portion between the vertical wall portions that are bent ~d stretched and the vertical wall portions that are bent back if the bending and stretching and the bending back are performed at the same time as each other. [0005] In consideration of the above circumstances, the present disclosure relates to obtaining a hat-shaped cross-section component manufacturing method in which the height of a preliminarily formed component can be changed while suppressing the occurrence of cracking or the like. 1 Solution to Problem [0006] A method for manufacturing a hat-shaped cross-section component addressing the above issue includes: a gripping process of disposing a pair of vertical walls of an elongated preliminarily formed component that has been formed into a hat shaped cross section profile at a width direction outer side of a punch, and gripping a top plate of the preliminarily formed component using the punch and a pad; a bending and stretching process of, after the gripping process, moving a die provided on both width direction sides of the pad toward a punch side relative to the preliminarily formed component, and using the die to bend and stretch the vertical walls toward an opposite side to the top plate at one side in a length direction of the preliminarily formed component; and a bend back process of, after the gripping process, moving a holder provided on both width direction sides of the punch toward a pad side ·relative to the preliminarily formed component, and using the holder to bend back the vertical walls toward a top plate side at another side in the length direction of the preliminarily formed component. [0007] According to the hat-shaped cross-section component manufacturing method addressing the above issue, in the gripping process, the top plate of the elongated preliminarily formed component that has been formed into a hat shaped cross section profile is gripped using the punch and the pad. When this is performed, the pair of vertical walls of the preliminarily formed component are disposed at the width direction outside of the punch. Then, in the bending and stretching process, after the gripping process, the die provided on both width direction sides of the pad is moved toward the punch side relative to the preliminarily formed component, and the die is used to bend and stretch the vertical walls toward the opposite side to the· top plate at one side in the length direction of the preliminarily formed component. In this manner, the height of the vertical walls at one side in the length direction of the preliminarily formed component is changed so as to become higher. [0008] On the other hand, in the bend back process, after the gripping process, the holder provided on both width direction sides of the punch is moved toward the pad side relative to the preliminarily fonned component. The holder is used to bend back the vertical walls toward the top plate side at another side in the length direction of the preliminarily forined component. In this manner, the height of the vertical walls at another side in the length direction of the preliminarily formed component is changed so as to become lower. [0009] Moreover, in cases in which the vertical wall portion that is bent and stretched and the vertical wall portion that is bent back are adjacent to each other in the length direction of the preliminarily formed component, the bend back process is performed after the bending and stretching process, or the bending and stretching process is performed after the bend back 2 ! process. This thereby enables the occurrence of cracking or the like to be suppressed at a boundary portion between the vertical wall portion that is bent and stretched and the vertical wall portion that is bent back. Moreover, by separating the vertical wall portion that is bent and stretched and the vertical wall portion that is bent back in the length direction of the preliminarily formed component, any effect from the bend back process on the vertical wall portion that is bent and stretched can be suppressed, and any effect from the bending and stretching process on the vertical wall portion that is bent back can be suppressed, even when bending and stretching and bending back are performed at the same time. Due to the above, the height of the preliminarily formed component can be changed while suppressing the occurrence of cracking or the like. Advantageous Effects of Invention [0010] The hat-shaped cross-section component manufacturing method of the present disclosure exhibits the excellent advantageous effect of enabling the height of a preliminarily formed component to be changed while suppressing the occurrence of cracking or the like. BRIEF DESCRIPTION OF DRAWINGS [0011] Fig. lAis a perspective view illustrating an example of a preliminary curving component formed by a first process of a hat-shaped cross-section component manufacturing method according to an exemplary embodiment. Fig. 1 B is a plan view illustrating the preliminary curving component illustrated in Fig. 1A from above. Fig. 1 C is a side view illustrating the preliminary curving component illustrated in Fig. lA from one width direction side. Fig. lD is a front view illustrating the preliminary curving component illustrated in Fig. lA from one length direction side. Fig. 2 is a perspective view corresponding to Fig. lA, illustrating a preliminary curving component in order to explain ridge lines at locations corresponding to a concave shaped curved portion and a convex shaped curved portion. Fig. 3A is a perspective view illustrating a metal stock sheet before forming. Fig. 3B is a perspective view illustrating a drawn panel. Fig. 4 is perspective view corresponding to Fig. 3B, illustrating locations in the drawn panel where cracks and creases are liable to occur. Fig. 5 is an exploded perspective view illustrating relevant portions of a manufacturing apparatus employed in the first process. Fig. 6A is a cross-section illustrating a stage at the start of processing of the 3 manufacturing apparatus illustrated in Fig. 5. Fig. 6B is a cross-section illustrating the manufacturing apparatus illustrated in Fig. 5 at a stage at which a metal stock sheet is gripped and restrained between a die and pad, and a holder and a punch. Fig. 6C is a cross-section illustrating a stage at which the punch has been pushed in from the stage illustrated in Fig. 6B. Fig. 6D is a cross-section illustrating a state in which the punch has been pushed in further from the stage illustrated in Fig. 6C, such that the punch has been fully pushed in with respect to the die. Fig. 7 is an exploded perspective view illustrating another manufacturing apparatus employed in the first process. Fig. SA is a cross-section illustrating the manufacturing apparatus illustrated in Fig. 7, at a stage at the start of processing. Fig. 8B is a cross-section illustrating a stage at which the metal stock sheet is gripped and restrained between a die and pad, and a holder and punch of the manufacturing apparatus illustrated in Fig. 7. Fig. 8C is a cross-section illustrating a stage at which the punch has been pushed in from the stage illustrated in Fig. 8B. Fig. 8D is a cross-section illustrating a state in which the punch has been pushed in further from the stage illustrated in Fig. 8C, such that the punch has been fully pushed in with respect to the die. Fig. 9A is a cross-section illustrating a mold to explain a defect that occurs when removing a preliminary cur¥ing component from the mold after a punch has been fully pushed into a die and a metal stock sheet has been formed into a preliminary curving component. Fig. 9B is a cross-section illustrating the mold at a stage in which the punch is being retracted from the die from the state illustrated in Fig. 9 A. Fig. 9C is a cross-section illustrating the mold at a stage in which the punch has been fully retracted from the die from the state illustrated in Fig. 9B. ~. " Fig. lOA is a cross-section illustrating a mold, in a state in which· a punch has been fully pushed into a die. Fig. 1 OB is a cross-section illustrating the mold at a stage in which the punch is being retracted from the die from the state illustrated in Fig. 1 OA. Fig. 1 OC is a cross-section illustrating the mold at a stage in which the punch has been fully retracted from the die from the state illustrated in Fig. 1 OB. 4 Fig. llA is a cross-section illustrating a mold, in a state in which a punch has been fully pushed into a die. Fig. llB is a cross-section illustrating the mold at a stage in which the punch is being retracted from the die from the state illustrated in Fig. llA. Fig. 11 C is a cross-section illustrating the mold at a stage in which the punch has been fully retracted from the die from the state illustrated in Fig. llB. Fig. 12Ais a perspective view illustrating another preliminary curving component formed by the first process. Fig. 12B is a plan view illustrating the preliminary curving component illustrated in Fig. 12Afrom above. Fig. 12C is a side view illustrating the preliminary curving component illustrated in Fig. 12A from one width direction side. Fig. 12D is a front view illustrating the preliminary curving component illustrated in Fig. 12A from one length direction side. Fig. 13A is a perspective view illustrating another preliminary curving component formed by the first process. Fig. 13B is a plan view illustrating the preliminary curving component illustrated in Fig. 13A from above. Fig. 13C is a side view illustrating the preliminary curving component illustrated in Fig. 13A from one width direction side. Fig. !3D is a perspective view illustrating the preliminary curving component illustrated in Fig. 13A from a bottom face side. Fig. 14A is a perspe,tive. view illustrating another preliminary curving component formed by the first process. Fig. 14B is a plan view illustrating the preliminary curving component illustrated in Fig. 14A from above. Fig. 14C is a side view illustrating the preliminary curving component illustrated in Fig. 14A from one width direction side. Fig: 14D is a front view illustrating the preliminary curving component illustrated in Fig. 14A from the other length direction side. Fig. 15A is a perspective view illustrating another preliminary curving component fanned by the first process. Fig. 15B is a plan view illustrating the preliminary curving component illustrated in Fig. 15Afrom above. Fig. 15C is a side view .illustrating the preliminary curving component illnstratcd in 5 Fig. 15A from one width direction side. Fig. 15D is a front view illustrating the preliminary curving component illustrated in Fig. 15A from the other length direction side. Fig. 16A is a perspective view illustrating another preliminary curving component formed by the first process. Fig. 16B is a plan view illustrating the preliminary curving component illustrated in Fig. 16A from above. Fig. 16C is a side view illustrating the preliminary curving component illustrated in Fig. l6A from one width direction side. Fig. 16D is a perspective view illustrating the preliminary curving component illustrated in Fig. l6A from a bottom face side. Fig. 17 A is a perspective view illustrating another preliminary curving component formed by the first process. Fig. 17B is a plan view illustrating the preliminary curving component illustrated in Fig. 17 A from above. Fig. 17C is a side view illustrating the preliminary curving component illustrated in Fig. 17 A from one width direction side. Fig. 17D is a perspective view illustrating the preliminary curving component illustrated in Fig. 17 A from a bottom face side. Fig. 18A is a perspective view illustrating a metal stock sheet before pre-processing. Fig. 18B is perspective view illustrating a pre-processed metal stock sheet. Fig. 18C is perspective view illustrating a preliminary curving component formed from the pre-processed metal sto<:k sheet. Fig. 18D is perspective view illustrating a state in which the preliminary curving component illustrated in Fig. 18C has been trimmed. Fig. 19 is a perspective view illustrating an example of an intermediate curving component that has been processed in a second process of a hat -shaped cross-section component manufacturing method according to the present exemplary embodiment. Fig. 20 is a side view of the intermediate curving co'~ponent illustrated in Fig. 19, as viewed from one width direction side. Fig. 21 is a perspective view illustrating relevant portions of a manufacturing apparatus employed in the second process. Fig. 22A is a perspective view illustrating the manufacturing apparatus illustrated in Fig. 21, at a stage at the start of processing. Fig. 22Bis a perspective view illustrating a stage at which a pad11nd a die have been 6 moved from the stage illustrated in Fig. 22A, and a top plate of a preliminary curving component is gripped and restrained between the pad and the punch. Fig. 22C is a perspective view illustrating a stage of a bending and stretching process in which the die is moved relatively toward the side of the punch from the stage illustrated in Fig. 22B and vertical walls at one side in the length direction of the preliminary curving component are bent and stretched. Fig. 22D is a perspective view illustrating a stage of a bend back process in which the holder is moved relatively toward the side of the die from the stage illustrated in Fig. 22C, and vertical walls at another side in the length direction of the preliminary curving component are bent back. Fig. 23 is a cross-section (a cross-section taken along line 23-23 in Fig. 22B) illustrating a state in which a portion at one side in the length direction of a top plate of the preliminary curving component is gripped and restrained by the pad and the punch at the stage illustrated in Fig. 22B. Fig. 24 is a cross-section (a cross-section taken along line 24-24 in Fig. 22B) illustrating a state in which a portion at another side in the length direction of a top plate of the preliminary curving component is gripped and restrained by the pad and the punch at the stage illustrated in Fig. 22B. Fig. 25 is a cross-section illustrating a stage of the bend back process illustrated in Fig. 22D. Fig. 26A is a perspective view illustrating a state prior to processing a preliminary curving component in a second process. Fig. 26B is a perspective view illustrating a state of a preliminary curving component that has been processed by a bending and stretching process of a second process. Fig. 27 is a perspective view illustrating an example of a completed curving component that has been processed by a third process of a hat -shaped cross-section component manufacturing method according to the present exemplary embodiment. Fig. 28 is a cross-section (a cross-section taken along line 28-28 in Fig. 27) viewed along the length direction illustrating an example of a completed curving component that has been processed by a third process of a hat -shaped cross-section component manufacturing method according to the present exemplary embodiment. Fig. 29A is a cross-section illustrating a stage at which a top plate of an intermediate curving component is supported from an apparatus lower side by a support member in a manufacturing apparatus employed in a third process. Fig. 29B. is a cross-section illustrating a stage at which, from the.stage illustrated in 7 Fig. 29A, the top plate of the intermediate curving component has been fitted into a first recess portion of a die and is being gripped and restrained by the die and the support member. Fig. 29C is a cross-section illustrating a stage at which, from the stage illustrated in Fig. 29B, a punch has been pushed into a second recess portion of the die. Fig. 29D is a cross-section illustrating a stage at which, from the stage illustrated in Fig. 29C, the punch has been pushed further into the second recess portion of the die, and the punch has been fully pushed in with respect to the die. Fig. 30A is a cross-section illustrating a stage at which a top plate of an intermediate curving component is supported from an apparatus lower side by a support member in another manufacturing apparatus employed in a third process. Fig. 30B is a cmss-section illustrating a stage at which, from the stage illustrated in Fig. 30A, the top plate of the intermediate curving component has been fitted into a first recess portion of a die and is being gripped and restrained by the die and the support member. Fig. 30C is a cross-section illustrating a stage at which, from the stage illustrated in Fig. 30B, a punch has been pushed into a second recess portion of the die. Fig. 30D is a cross-section illustrating a stage at which, from the stage illustrated in Fig. 30C, the punch has been pushed further into the second recess portion of the die, and the punch has been fully pushed in with respect to the die. Fig. 31A is a cross-section illustrating a stage at which a top plate of an intermediate curving component is supported from an apparatus lower side by a support member in another manufacturing apparatus employed in a third process. Fig. 31 B is a cross-section illustrating a stage at which, from the stage illustrated in Fig. 31 A, the top plate of the intermediate curving component has .been fittecl into a first recess portion of a die and is being gripped and restrained by the die and the support member. Fig. 31 C is a cross-section illustrating a stage at which, from the stage illustrated in Fig. 31 B, a punch has been pushed into a second recess portion of the die. Fig. 31 D is a cross-section illustrating a stage at which, from the stage illustrated in Fig. 31C, the punch has been pushed further into the second recess portion of the die, and the punch has been fully pushed in with respect to the die. Fig. 32A is a cross-section corresponding to Fig. 31A, illustrating a stage at which a top plate of an intermediate curving component is supported from an apparatus lower side by a support member in another manufacturing apparatus employed in a third process. Fig. 32B is a cross-section corresponding to Fig. 31B, illustrating a stage at which, from the stage illustrated in Fig. 32A, the top plate of the intermediate curving component has been_ fitted into a first recess portion of a die and is being gripped and restrained by the die 8 and the support member. Fig. 32C is a cross-section corresponding to Fig. 31 C, illustrating a stage at which, from the stage illustrated in Fig. 32B, a punch has been pushed into a second recess portion of the die. Fig. 32D is a cross-section corresponding to Fig. 31D, illustrating a stage at which, from the stage illustrated in Fig. 32C, the punch has been pushed further into the second recess portion of the die, and the punch has been fully pushed in with respect to the die. Fig. 33A is a perspective view of a preliminary curving component, schematically illustrating stress occurring in vertical walls. Fig. 33B is a perspective view of the preliminary curving component, illustrating shear creasing occurring in the vertical walls. Fig. 33C is a side view of the preliminary curving component, illustrating shear creasing occurring in the vertical walls. Fig. 34A is a cross-section of a manufacturing apparatus to explain the dimensions and the like of respective portions in order to prevent the occurrence of shear creasing. Fig. 34B is a cross-section of a preliminary curving component to explain the dimensions and the like of respective portions in order to prevent the occurrence of shear creasmg. Fig. 34C is a cross-section of a manufacturing apparatus to explain the dimensions and the like of respective portions in order to prevent the occurrence of shear creasing. Fig. 34D is cross-section of a preliminary curving component to explain the dimensions and the like of respective portions in order to prevent the occurrence of shear ereasmg. Fig. 35 is a table to explain circumstances under which creasing occurs in a preliminary curving component when various parameters are changed in a first process. Fig. 3 6A is a perspective view illustrating a preliminary curving component manufactured using the manufacturing apparatus illustrated in Fig. 5. Fig. 36B is a plan view illustrating the preliminary curving component illustrated in Fig. 36A from above. Fig. 36C is a side view illustrating the preliminary curving component illustrated in Fig. 36A from one width direction side. Fig. 36D is a front view illustrating the preliminary curving component illustrated in Fig. 36A from one length direction side. Fig. 37 is a cross-section of a mold, illustrating the clearance in the table in Fig. 35. Fig. 3 8 is a side view to explain another example of an intermediate curving 9 component processed by a second process in a hat -shaped cross-section component manufacturing method according to an exemplary embodiment. Fig. 39 is a cross-section corresponding to Fig. 23, illustrating a modified example of the manufacturing apparatus illustrated in Fig. 21, in a state in which a portion at one side in the length .direction of a top plate of a preliminary curving component is gripped and restrained by a pad and a punch. Fig. 40 is a cross-section corresponding to Fig. 24, illustrating a modified example of the manufacturing apparatus illustrated in Fig. 21, in a state in which a portion at another side in a length direction of a top plate of a preliminary curving component is gripped and restrained by a pad and a punch. Fig. 41 is a cross-section corresponding to Fig. 25, illustrating a modified example of the manufacturing apparatus illustrated in Fig. 21, at a bend back process stage. DESCRIPTION OF EMBODIMENTS [0012] Explanation follows regarding a manufacturing method for a hat-shaped cross-section component according to an exemplary embodiment, with reference to the drawings. The hat-shaped cross-section component manufacturing method includes a first process (shear forming process) of a "preliminary forming process" for forming a preliminarily formed component, a second process (intermediate process) for processing (forming) the preliminarily formed component to change the height of the preliminarily formed component, and a third process, serving as a "restriking process", for restriking the preliminarily formed component that has undergone the second process. Explanation follows regarding each of these. processes. Note that in the drawings, equivalent members and the like are allocated the same reference numerals, and in the following explanation, duplicate explanation of equivalent members is omitted as appropriate after being described for the first time. [00!3] First Process As illustrated in Fig. 5, in the first process, a preliminary curving component I 0 (see Fig. 2) is formed as a "preliminarily formed component" and a "curved member" by drawing a metal stock sheet 601 using a manufacturing apparatus 500. Explanation first follows regarding configuration of the preliminary curving component 10, followed by explanation regarding the manufacturing apparatus 500, and then explanation regarding the first process. [00 14] Preliminary curving component I 0 Configuration As illustrated in Fig. lA to Fig. lD and Fig. 2, the preliminary curving component 10 is configured from high strength sheet steel having tensile strength of from 200 MPa to 1960 10 MPa. The preliminary curving component I 0 is formed in an elongated shape, and is formed with a hat shape as viewed in cross-section along its length direction. Specifically, the preliminary curving component 10 includes a top plate II extending along the length direction, and respective vertical walls 12a, 12b that are bent so as to extend toward the lower side (one sheet thickness direction side of the top plate 11) from both width direction sides of the top plate 1 L The preliminary curving component 10 further includes respective flanges 13a, 13b that are bent so as to extend toward the width direction outside of the top plate 11 from lower ends (ends on the opposite side to the top plate 11) of the vertical walls 12a, 12b. [0015] Ridge lines 14a, 14b are formed, extending along the length direction of the preliminary curving component 10, between the top plate 11 and the respective vertical walls 12a, 12b. Ridge lines 15a, 15b are formed extending along the length direction of the preliminary curving component 10 between the respective vertical walls 12a, 12b and the flanges 13a, 13b. [0016] The ridge lines 14a, 14b and the ridge lines 15a, 15b are provided extending substantially parallel to each other. Namely, the height of the respective vertical walls 12a, 12b that extend from the respective flanges 13a, 13b toward the upper side (the other sheet thickness direction side of the top plate 11) is substantially uniform along the length direction of the preliminary curving component 10. [00 17] As illustrated in Fig. 2, as viewed from the side, a portion of the top plate 11 is formed with a convex shaped curved portion lla that curves in an arc shape toward the outside of the lateral cross-section profile of the hat shape, namely, toward the outer surface side (other sheet thickness direction side) of the top plate 11. Another portion of the top plate 11 is formed with a concave shaped curved portion llb that curves in an arc shape toward the inside of the lateral cross-section profile of the hat shape, namely, toward the inner smface side (one sheet thickness direction side) of the top plate 11. At the convex shaped curved portion 11 a and the concave shaped curved portion 11 b, the ridge lines 14a, 14b between the top plate 11 and the vertical walls 12a, 12b are also curved in arc shapes, at locations 16a, 16b, and 17a, 17b, corresponding to the convex shaped curved portion lla and the concave shaped curved portion 11 b. Note that an "arc shape" is not limited to part of a perfect circle, and may be part of another curved line, such as of an ellipse, a hyperbola, or a smewave. [00 18] The preliminary curving component I 0 described above is formed by forming a drawn panel301 (see Fig. 3B) by drawing a rectangular shaped metal stock sheet 201, serving as a "metal sheet", illustrated in Fig. 3A, and then trimming unwanted portions of the drawn panel301. 11 [00 19] However, when manufacturing the preliminary curving component 10 with a hat-shaped cross-section by drawing, excess material is present during the drawn panel301 forming stage at a concave shaped curved portion top plate 30la and a convex shaped curved portion flange 30lb of the drawn panel301, as illustrated in Fig. 4, and creases are liable to occur. Increasing restraint at the periphery of the metal stock sheet 201 during the process of forming by, for example, raising the pressing force of a blank holder, or adding locations to the blank holder for forming draw beads, and thereby suppressing inflow of the metal stock sheet 201 into the blank holder, are known to be effective in suppressing the occurrence of creases. [0020] However, when there is enhanced suppression of inflow of the metal stock sheet 201 into the blank holder, there is also a large reduction in the sheet thickness of the drawn panel 301 at respective portions, including at a convex shaped curved portion top plate 301c, a concave shaped curved portion flange 30ld, and both length direction end portions 301e, 30le. In cases in which the metal stock sheet 201 is a material with particularly low extensibility (for example high tensile steel), it is conceivable that cracking could occur at these respective portions. [0021] Accordingly, due to endeavoring to avoid creasing and cracking in the manufacture by pressing using drawing of curving components with a hat-shaped cross-section, such as front side members configuring part of a vehicle body framework, it has been difficult to employ high strength materials with low extensibility as the metal stock sheet 201, meaning that low strength materials with high extensibility have had to be employed. [0022] However, the occurrence of such creasing and cracking can be suppressed by 9erforming the first process, described later, employing the manufacturing apparatus 500 of the present exemplary embodiment [0023] Manufacturing Apparatus 500 Next, explanation follows regarding the manufacturing apparatus 500. Fig. 5 is an exploded perspective view illustrating the manufacturing apparatus 500 employed to manufacture a preliminary curving component 501 serving as a "preliminarily formed component". Note that configuration of the preliminary curving component 501 is substantially the same as the configuration of the preliminary curving component 10 (see Fig. lA). Fig. 6Ais a cross-section illustrating the manufacturing apparatus illustrated in Fig. 5 at the start of processmg. Fig. 6B is a cross-section illustrating the manufacturing apparatus illustrated in Fig. 5 at a stage at which a metal stock sheet 601 is gripped and restrained between a preliminary forming die 502 and preliminary forming pad 503, and preliminary forming blank holders 505 and preliminary forming punch 504. Fig. 6C is a cross-section illustrating a 12 stage at which the preliminary forming punch 504 has been pushed in from the stage illustrated in Fig. 6B. Fig. 6D is a cross-section illustrating a state in which the preliminary forming punch 504 has been pushed in further from the stage illustrated in Fig. 6C, such that the preliminary forming punch 504 has been fully pushed in with respect to the preliminary forming die 502. (0024] As illustrated in Fig. 5, the manufacturing apparatus 500 is configured including the preliminary forming die 502 (referred to below as simply the "die 502") that has a shape corresponding to respective outer surface side profiles of vertical walls 501 a, 501 b, and flanges 50ld, SOle, of the preliminary curving component 501, and the preliminary forming pad 503 (referred to below as simply the "pad S03 ") that has a shape corresponding to the outer surface side profile of a top plate SOle. The manufacturing apparatus 500 further includes the preliminary forming punch S04 (referred to below as simply the "punch 504") that is disposed facing the die 502 and the pad S03 and that has a shape corresponding to respective inner surface side profiles of the top plate SOle and the vertical walls SOla, SOlb of the preliminary curving component 501, and the preliminary forming blank holders 505 (referred to below as simply the "blank holders 505"), serving as a "preliminary forming holder", with a shape corresponding to inner surface side profiles of the flanges SOld, SOle. [0025] As illustrated in Fig. 6A to Fig. 6D, the die 502 and the punch 504 are disposed facing each other along the apparatus up-down direction, and the die 502 is disposed at the apparatus upper side of the punch 504. A central portion in the width direction (the left-right direction on the page) of the die 502 is formed with a recess 502a opening toward the apparatus lower side (the punch 504 side). Inner peripheral faces of the recess 502a of the die 502 configure forming faces corresponding to the profile of the outer surfaces oft he vertical walls SOla, 50lb (see Fig. 5) of the preliminary curving component 501. Moreover, end faces on the apparatus lower side (the blank holder 505 side) of both die 502 width direction side portions configure forming faces corresponding to the profile of upper faces (the faces on the vertical walls SOla, 50lb (see Fig. 5) sides) of the flanges SOld, SOle of the preliminary curving component 501. A pad press unit 506, described later, is fixed to the closed off end (upper end) of the recess 502a formed in the die 502. Moreover, the die 502 is coupled to a mover device 509 such as a gas cushion, a hydraulic drive, a spring, or an electric drive mechanism. Actuating the mover device 509 moves the die 502 in the apparatus up-down direction. [0026] The pad 503 is disposed inside the recess 502a formed to the die 502. The pad 503 is coupled to the pad press unit 506, this being a gas cushion, a hydraulic drive, a spring, an electric drive mechanism, or the like. A face on the punch 504 side of the pad 503 13 configures a forming face including the profile of the outer surface of the top plate SOle (see Fig. S) of the preliminary curving component SOl. When the pad press unit S06 is actuated, the pad S03 is pressed toward the punch S04 side, and a central portion 60 lain the width direction (the left-right direction on the page) of the metal stock sheet601 is pressed and gripped between the pad S03 and the punch S04. [0027] The punch 504 is formed by a shape protruding toward the pad 503 side at a location in a lower mold that faces the pad S03 in the up-down direction. Blank holder press units S07, described later, are fixed at the sides of the punch S04. Outer faces of the punch S04 configure forming faces corresponding to the profile of the respective inner surfaces of the vertical walls 50la, 50lb and of the top plate SOle (see Fig. S) of the preliminary curving component SOl. [0028] The blank holders SOS are coupled to the blank holder press units S07, serving as holder press units, these being gas cushions, hydraulic drives, springs, electric drive mechanisms, or the like. Apparatus upper side (die S02 side) end faces of the blank holders SOS configure forming faces corresponding to the profile of lower faces (faces on the opposite side to the vertical walls SOla, SOlb (see Fig. S)) of the flanges 50l hnlcler 714. Aec.onlingly, the ridge lines 129q, 1?9b between th') vertical walls.124a, 124b and the flanges 126a, 126b at another side in the length direction of the preliminary curving component 120 are gradually moved toward the apparatus upper side (in a direction approaching the top plate 122 side), and the flanges 126a, 126b at another side in the length direction of the preliminary curving component 120 ru:e moved toward the apparatus upper side while following the upper face of the holder 714. [0132] Then, as illustrated in Fig. 41, when the die 711, the pad 712, and the punch 713 have reached their stroke end positions, the flanges 126a, 126b of the preliminary curving component 120 are pressed and gripped by the holder 714 and the die 711, and the flanges 706a-2, 706b-2 of the intennediate curving component 700 are formed. Due to the above, when the holder 714 is configured so as to be incapable of movement, moving the die 711, the pad 712, and the punch 713 toward the apparatus lower side relative to the holder 714 enables the veJiical walls 704a-2, 704b-2 and the flanges 706a-2,706b-2 at another side in the length 43 direction of the intermediate curving component 700 to be formed. [0133] Accordingly, in the bend back process of the present disclosure, "moving a holder provided on both width direction sides of the punch toward the pad side relative to the preliminarily formed component" encompasses moving the holder 714 toward the pad 712 side (die 711 side) relative to the preliminary curving component 120 by moving the pad 712 and the punch 713 toward the holder 714 side_ [0134] Moreover, in the present exemplary embodiment, in the intermediate curving component 700, the vertical wall 704a-l that is bent and stretched in the bending and stretching process and the vertical wall 704a-2 that is bent back in the bend back process are adjacent to each other in the length direction of the intermediate curving component 700. Namely, in the second process, the height dimension of the intermediate curving component 700 (the vertical walls 704) is changed "continuously" over the entire length direction of the intermediate curving component 700. In other words, the height is changed across the entire intermediate curving component 700 (vertical walls 704). Alternatively, the vertical wall 704a-l that is bent and stretched in the bending and stretching process and the vertical wall 704a-2 that is bent back in the bend back process may be separated from each other in the length direction of the intermediate curving component 700; Namely, the height dimension of the intermediate curving component 700 (vertical walls 704) may be changed "intermittently" over the entire length of the intermediate curving component 700. In other words, the height of the intermediate curving component 700 (vertical walls 704) may be changed locally. For example, as illustrated in Fig. 20, the vertical wall 704a-l at one side in the length direction of the vertical wall 704, may be bent and stretched in the bending and stretching process except for at a .length direction inte~medi.~te portion (a portion connected to the convex shaped curved portion 702a; the hatched portion in Fig. 20), and the vertical wall 704a-2 at another side in the length direction of the vertical wall 704 may be bent back in the bend back process except for at the length direction intermediate portion. Moreover, in such cases, in the second process, the bending and stretching process and the bend back process may be performed at the same time as each other. [0135]. Namely, in cases in which the height dimension of the intermediate curving component 700 (vertical walls 704) is changed "intermittently" over the entire length direction of the intermediate curving component 700, as described above, the bent and stretched vertical wall 704a-l and the bent back vertical wall 704a-2 are separated from each other in the length direction about the length direction intermediate portion of the vertical wall 704. Accordingly, even if the bending and stretching process and the bend back process are perfonned at the same time as each other, any effect on the vertical wall 704a-l from the bend 44 back process is suppressed by the length direction intermediate portion of the vertical wall 704, and any effect on the vertical wall 704a-2 from the bending and stretching process is suppressed by the length direction intermediate portion of the vertical wall 704. Accordingly, even if the bending and stretching process and the bend back process are performed at the same time as each other, by separating the vertical wall 704a-1 that is bent and stretched and the vertical wall 704a-2 that is bent back from each other in the length direction of the intermediate curving component 700, cracking or the like can be suppressed from occurring at the length direction intermediate portion of the vertical wall 704. [0136] Positioning pins may be provided to the punch and/or the support member in order to raise the positioning precision of the curving component with respect to the die and the punch of the second process and the third process of the present exemplary embodiment. For example, to explain using the third process, a positioning pin may be provided to the support portion 828a of the support member 828 so as to project out toward the apparatus upper side, and a positioning hole into which the positioning pin is inserted may be formed to the top plate 702 of the intermediate curving component 700. In such cases, for example, the positioning hole is formed in a process prior to the first process by preprocessing the metal stock sheet, and the die 822 is formed with a recess so as not to interfere with the positioning pm. [0 13 7] In order to raise the length direction positioning precision of the intermediate curving component 700 with respect to the die 822 and the punch 826, for example, the support member 828 may be provided with guide pins that contact both length direction ends of the top plate 702, or guide walls that contact both length direction ends of the vertical walls 704a, 704b. [0138] In the manufacturing apparatus 820 employed in the third process of the present exemplary embodiment, the support member 828 extends along the length direction of the intermediate curving component 700 so as to support the top plate 702 of the intermediate curving component 700 continuously along the length direction. However, the support member 828 may be split up such that the top plate 702 of the intermediate curving component 700 is supported intermittently by the support member 828. For example, configuration may be made such that both length direction end portions and a length direction intermediate portion of the top plate 702 are supported by the support member 828. [0139] In the manufacturing apparatus 820 employed in the third process of the present exemplary embodiment, the iorming recess 824 formed to the die 822 is configured including the first recess portion 824a and the second recess portion 824b. Namely, the forming recess 824 is configured by two recess portions. Alternatively,. the forming recess 824 may be 45 configured by three or more recess portions. For example, a third recess portion with a larger width dimension than the second recess portion 824b may be formed on the opening side of the second recess portion 824b. In such cases, the external profile of the punch 826 is modified as appropriate to correspond to the forming recess 824. [0140] Moreover, in the hat-shaped cross-section component manufacturing method of the present exemplary embodiment the completed curving component serving as a hat-shaped cross-section member is formed by going through the first process to the third process. However, in cases in which the dimensional precision of the intermediate curving component is comparatively high, the third process may be omitted from the hat-shaped cross-section component manufacturing method. In such cases, the· intermediate curving component configures the completed component. [0 141] Moreover, in the above explanation, explanation has been given regarding an example in which sheet steel is employed as the metal stock sheet; however, the material of the metal stock sheet is not limited thereto. For example, an aluminum, titanium, stainless steel, or composite material, such as an amorphous material may be employed as the metal stock sheet. [0142] Explanation has been given above regarding an exemplary embodiment of the present invention. However, the present invention is not limited to the above, and obviously various other modifications may be implemented within a range not departing from the spirit of the present invention. [0143] The disclosure ofJapanese Patent Application No. 2014-259102, filed on December 22, 2014, is incorporated in the present specification in its entirety by reference herein. [0144J Supplement In a method for manufacturing a hat-shaped cross-section component according to a first aspect, the manufacturing method includes: a gripping process of disposing a pair of vertical walls of an elongated preliminarily formed component that has been formed into a hat shaped cross section profile at a width direction outside of a punch, and gripping a top plate of the preliminarily formed component using the punch and a pad; a bending and stretching process of, after the gripping process, moving a die provided on both width direction sides of the pad toward the punch side relative to the preliminarily formed component, and using the die to bend and stretch the vertical walls toward the opposite side to the top plate at one side in the length direction of the preliminarily formed component; and a bend back process of, after the gripping process, moving a holder provided on both width direction sides of the punch toward the pad side relative to the preliminarily formed component, and using the holder to bend back the vertical walls toward the to.p plate side at another side in the length 46 direction of the preliminarily formed component. [0 145] Moreover, configuration is preferably made in which the preliminarily formed component is a curved member including a curved portion that is convex on an outer surface side of the top plate in side view; in the bending and stretching process, the vertical walls are bent and stretched at one side in the length direction of the curved portion; in the bend back process, the vertical walls are bent back at another side in the length direction of the curved portion; and the bend back process is performed after the bending and stretching process. [0 146] Moreover, configuration is preferably made in which the preliminarily formed component is a curved member including a curved portion that is convex on an inner surface side of the top plate in side view; in the bending and stretching process, the vertical walls are bent and stretched at one side in the length direction of the curved portion; in the bend back process, the vertical walls are bent back at another side in the length direction of the curved portion; and the bending and stretching process is performed after the bend back process. [0 14 7] Moreover, configuration is preferably made in which the vertical wall portion that is stretched in the bending and stretching process and the vertical wall portion that .is bent back in the bend back process are adjacent to each other in the length direction of the hat-shaped cross-section component; in the bending and stretching process, a bending and stretching amount of the vertical walls is set so as to become larger on progression toward the one side in the length direction of the preliminarily formed component; and in the bend back process, a bend back amount of the vertical walls is set so as to become larger on progression toward the other side in the length direction toward the other side in the length direction of the preliminarily formed component. [0148] Moreover, confismntion is prefemhly made in which, in a preliminary formins process in which the preliminarily formed component is formed: a central portion of a metal sheet is gripped by a preliminary forming punch and a preliminary form-ing pad to configure an upward and downward curved metal sheet; both side portions of the metal sheet are gripped by a preliminary forming die and a preliminary forming holder provided on both width direction sides of the preliminary forming punch; and the preliminarily formed component is formed by moving the preliminary forming punch and the preliminary forming pad vertically relative to the preliminary forming holder and the preliminary form-ing die. [0 149] Moreover, configuration is preferably made in which the preliminarily formed component is configured from a steel sheet having a sheet thickness of from 0.8 mm to 3.2 mm and a tensile strength offrom 200 MPa to 1960 MPa. [0150] Moreover, configuration is preferably made further including a restriking process of restriking the hat-shaped cross-section component that has been through the bending and 47 stretching process and the bend back process. The restriking process includes: disposing the hat-shaped cross-section component between a restriking punch and a restriking die disposed so as to face each other, and supporting a top plate of the hat -shaped cross-section component from the restriking punch side using a support member extending from the restriking punch toward the restriking die side; housing the top plate inside a first recess portion configuring a top face side of a forming recess that is formed to the restriking die and that is open toward the restriking punch side, gripping the top plate using the support member and the restriking die, and positioning the hat-shaped cross-section component in a width direction using the first recess portion and a pair of vertical walls of the hat-shaped cross-section component; and inserting the restriking punch inside a second recess portion configuring the opening side of the forming recess and having a larger width dimension than the first recess portion, and restriking the hat -shaped cross-section component using the restriking punch and the restriking die. [0 151] Moreover, configuration is preferably made in which in the restriking process, the hat-shaped cross-section component is restruck using the restriking punch,and the restriking die in a state in which flanges configuring both width direction end portions of the hat-shaped cross-section component are in a free state. [0152] Configuration is preferably made in which in the restriking process, a restriking pad configuring part of the restriking die is disposed so as to extend toward the restriking punch side, and the top plate of the hat -shaped cross-section component supported by the support member is housed inside the first recess portion while being gripped using the restriking pad and the support member. [0153] Configuration is p~eferahly made in which the support member employed is contacted by the pair of vertical walls of the hat-shaped cross-section component [0154] In a manufacturing method for a hat-shaped cross-section component according to a second aspect, the manufacturing method includes: a bending and stretching process of gripping a top plate of an elongated preliminarily formed component that has been formed into a hat shaped cross section profile using a punch and a pad, moving a die disposed facing the punch relatively toward the punch side and using the die to bend and stretch vertical walls toward the opposite side to the top plate at one side in the length direction of the preliminarily formed component; and a bend back process of, after bending and stretching the vertical walls, moving a holder provided on both width direction sides of the punch relatively toward the die side, and using the holder to bend back the vertical walls toward the top plate side at another side in the length direction of the preliminarily formed component. (0155] Moreover, configuration is preferably made in which the preliminarily formed 48 component is a curved member including a curved portion that is convex on an outer surface side or an inner surface side of the top plate in side view; in the bending and stretching process, the vertical walls are bent and stretched at one side in the length direction of the curved portion; and in the bend back process, the vertical walls are bent back at another side in the length direction of the curved portion. CLAIMS 1. A method for manufacturing a hat -shaped cross-section component, the manufacturing method comprising: a gripping process of disposing a pair of vertical walls of an elongated preliminarily formed component that has been formed into a hat -shaped cross-section profile at a width direction outer side of a punch, and gripping a top plate of the preliminarily formed component using the punch and a pad; a bending and stretching process of, after the gripping process, moving a die provided on both width direction sides of the pad toward a punch side relative to the preliminarily formed component, and using the die to bend and stretch the vertical walls toward an opposite side to the top plate at one side in a length direction of the preliminarily formed component; and a bend back process of, after the gripping process, moving a holder provided on both width direction sides of the punch toward a pad side relative to the preliminarily formed compcment, and using the holder to bend back the vertical walls toward a top plate side at another side in the length direction of the preliminarily formed component. 2. The hat-shaped cross-section component mannfacturing method of claim 1, wherein: the preliminarily formed component is a curved member including a curved portion that is convex on an outer surface side of the top plate in side view; in the bending and stretching process, the vertical walls are bent and stretched at one side in the length direction of the curved portion; in the bend back process, the vertical walls are bent back at another side in tbe length direction of the curved portion; and the bend back process is performed after the bending and stretching process. 3. The hat -shaped cross-section component manufacturing method of claim 1, wherein: the preliminarily formed component is a curved member including a curved portion that is convex on an inner surface side of the top plate in side view; in the bending and stretching process, the vertical walls are bent and stretched at one side in the length direction of the curved portion; in the bend back process, the vertical walls are bent back at another side in the length direction of the curved portion; and the bending and stretching process is performed after the bend back process. 50 4. The hat-shaped cross-section component manufacturing method of either claim 2 or claim 3, wherein: a vertical wall portion that is stretched in the bending and stretching process and a vertical wall portion that is bent back in the bend back process are adjacent to each other in a length direction of the hat-shaped cross-section component; in the bending and stretching process, a bending and stretching amount of the vertical walls is set so as to become larger on progression toward the one side in the length direction of the preliminarily formed component; and in the bend back process, a bend back amount of the vertical walls is set so as to become larger on progression toward the other side in the length direction of the preliminarily formed component. 5. The hat-shaped cross-section component manufacturing method of any one of claim I to claim 4, wherein, in a preliminary forming process in which the preliminarily formed .component is formed: a central portion of a metal sheet is gripped by a preliminary forming punch and a preliminary forming pad to form an upward and downward curved metal sheet; both side portions of the metal sheet are gripped by a preliminary forming die and a preliminary forming holder that is provided on both width direction sides of the preliminary forming punch; and the preliminarily formed component is formed by moving the preliminary forming punch and the preliminary forming pad vertically relative to the preliminary forming holder and the preliminary fonning die. 6. The hat-shaped cross-section component manufacturing method of any one of claim I to claim 5, wherein the preliminarily formed component is configured from a steel sheet having a sheet thickness of from 0.8 mm to 3.2 mm and a tensile strength of from 200 MPa to 1960 MPa. 7. The hat-shaped cross-section component manufacturing method of any one of claim I to claim 6, further comprising: a restriking process of restriking the hat-shaped cross-section component that has been through the bending and stretching process and the bend back process, wherein the restriking process comprises: disposing the hat-shaped cross-section component between a restriking 51 punch and a restriking die, which are disposed so as to face each other, and suppmiing a top plate of the hat-shaped cross-section component from a restriking punch side using a support member extending from the restriking punch toward the restriking die side; housing the top plate of the hat-shaped cross-section component inside a first recess portion configuring a top face side ofa forming recess that is formed at the restriking die and that is open toward the restriking punch side, gripping the top plate using ' the support member and the restriking die, and positioning the hat -shaped cross-section component in a width direction using the first recess portion and a pair of vertical walls of the hat-shaped cross-section component; and inserting the restriking punch inside a second recess portion configuring the opening side ofthe forming recess and having a larger \Nidth dimension than the first recess portion, and restriking the hat-shaped cross-section component using the restriking punch and the restriking die. • 8. The hat-shaped cross-section component manufacturing method of claim 7, wherein, in the restriking process, the hat-shaped cross-section component is restruck using the restriking punch and the restriking die in a state in which flanges configuring both width direction end portions of the hat-shaped cross-section component are in a free state. 9. The hat-shaped cross-section component manufacturing method of either claim 7 or claim · 8, wherein, in the restriking process, a restriking pad configuring part of the restriking die is disposed so as to extend toward the restriking punch side, and the top plate of the hat -shaped cross-section c:omponent supported by the support member is housed inside. the first recess portion while being gripped using the restriking pad and the support member. 10. The hat-shaped cross-section component manufacturing method of any one of claim 7 to claim 9, wherein the support member employed is contacted by the pair of vertical walls of the hat -shaped cross-section component.