JP2010120061A - Press-formed product, and method and apparatus for manufacturing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reduce the weight and the manufacturing cost of a press-formed product having an open section with a bent part. <P>SOLUTION: The press-formed product 120 has an open section and has a bent part in the longitudinal direction Y. The bent part has a curved inner wall part 124A, and a connecting wall part 126 extending in the direction crossing the longitudinal direction Y from an end of the inner wall part 124A. The thickness of one part of the connecting wall part 126 adjacent to at least the inner wall part 124A is increased by the press forming compared with the thickness before the press forming. The thickness of a part 137 with the increased thickness is larger than that of a peripheral part of the part 137. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a press-formed product, a method for manufacturing a press-formed product, and a manufacturing apparatus.

A press-formed product having an open cross section having a bent portion that is applied to a vehicle suspension component or the like is manufactured from a tailored blank (see, for example, Patent Document 1). A tailored blank is formed by previously joining and integrating two dissimilar steel plates, and one of the dissimilar steel plates is made of a thick steel plate and requires a local part (for example, other parts) that requires rigidity or strength. The other of the dissimilar steel plates is made of a thin steel plate, and is applied to a portion where rigidity or strength is relatively not required.
JP 2005-152975 A

  Since one of the dissimilar steel plates is made of a thin steel plate, it is possible to reduce the weight of the press-formed product having an open section having a bent portion, but there is a problem in manufacturing cost. That is, since joining of dissimilar steel plates is performed by welding the butt portions of dissimilar steel plates, high butt accuracy is required, and it is difficult to improve productivity, leading to an increase in manufacturing cost. .

  The present invention has been made to solve the problems associated with the above-described prior art, and aims to reduce the weight and manufacturing cost of an open section press-formed product having a bent portion.

  The uniform phase of the present invention for achieving the above object is a method for producing an open-section component having a bent portion by press molding, and includes a preparation step, an arrangement step, and a thickness increase step. In the preparation step, a bent portion having an open cross section and extending in the direction of the open cross section is provided, and the bent portion is disposed apart from the curved inner wall portion and the inner wall portion. A preformed body having an outer wall portion and a connecting wall portion that connects an end portion of the inner wall portion and an end portion of the outer wall portion, or the bent portion is a curved inner wall portion; A pre-formed body having a connecting wall portion extending in a direction intersecting with a direction in which the open cross section extends from an end portion of the inner wall portion is prepared. In the placement step, the preform is placed in a mold. In the thickening step, in the middle of the mold clamping operation of the molding die, the inner wall portion is pushed by the molding die to generate a material flow, and at least the connecting wall portion adjacent to the inner wall portion. The thickness of a part of the plate is increased compared with the plate thickness before the mold clamping operation.

  Another uniform phase of the present invention for achieving the above object has an open cross section, provided with a bent portion in a direction in which the open cross section extends, and the bent portion includes a curved inner wall portion, A press-molded product having an outer wall portion spaced apart from the inner wall portion, and a connecting wall portion that connects an end portion of the inner wall portion and an end portion of the outer wall portion, or the bent portion Is a press-formed product having a curved inner wall part and a connecting wall part extending from the end of the inner wall part in a direction intersecting with the direction in which the open cross section extends. In the press-molded product, the plate thickness of at least a portion of the connecting wall portion adjacent to the inner wall portion is increased by press molding as compared to the plate thickness before the press molding, and the The thickness of the portion where the thickness is increased is larger than the thickness of the peripheral portion of the portion.

  Another aspect of the present invention for achieving the above object is an apparatus for manufacturing an open cross-section part having a bent portion by press molding, which has a molding die on which a preform is placed and clamped . The preform has an open cross section, and is provided with a bent portion extending in a direction in which the open cross section extends, and the bent portion is disposed apart from the curved inner wall portion and the inner wall portion. An outer wall part, and a connecting wall part that connects an end part of the inner wall part and an end part of the outer wall part, or the bent part includes a curved inner wall part, A connecting wall extending from the end of the inner wall in a direction intersecting with the direction in which the open cross section extends. The molding die has a punch portion disposed inside the preform and a die portion disposed outside the preform. The die part is disposed apart from and relative to the fixed mold for pressing the outer wall part and a part of the connecting wall part adjacent to the outer wall part in cooperation with the punch part, A movable mold that presses a portion of the connecting wall adjacent to the inner wall portion in cooperation with the punch portion, and that pushes the inner wall portion and mold-clamps relative to the fixed mold; Is included. Further, the sectional thickness of the cavity formed by the punch portion and the movable die at the time of mold clamping is at least related to the plate thickness of a part of the connecting wall portion adjacent to the inner wall portion, than the plate thickness of the preform. It is set large. The punch part and the die part generate a material flow by pushing the inner wall part of the bent part by the movable mold in the middle of the mold clamping operation of the molding die, and at least the inner side A plate thickness of a part of the connecting wall portion adjacent to the wall portion is increased as compared with a plate thickness before the mold clamping operation.

  According to the method and the apparatus relating to the uniform phase and the other uniform phase of the present invention, the plate thickness of at least a part of the connecting wall portion adjacent to the inner wall portion in the bent portion in the extending direction of the open cross section is obtained by press molding. As compared with the plate thickness before press molding, an increased press molded product (part) is manufactured. The rigidity or strength of the press-formed product is ensured by the portion where the plate thickness is increased, and the portion where the plate thickness is increased is not the whole of the bent portion but is partial, so It is possible to easily reduce the weight. Moreover, since the site | part where the plate | board thickness is increasing is formed by press molding which has favorable productivity compared with the tailored blank to which butt welding is applied, manufacturing cost is reduced. Therefore, it is possible to reduce the weight and manufacturing cost of the press-formed product having an open cross section having a bent portion.

  In the press-formed product according to another uniform phase of the present invention, the rigidity or strength of the press-formed product is ensured by a portion where the plate thickness is increased, and the portion where the plate thickness is increased is a bent portion. Therefore, it is possible to easily reduce the weight of the press-formed product. Moreover, since the site | part where the plate | board thickness is increasing is formed by press molding which has favorable productivity compared with the tailored blank to which butt welding is applied, manufacturing cost is reduced. Therefore, it is possible to reduce the weight and manufacturing cost of the press-formed product having an open cross section having a bent portion.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  1 is a perspective view for explaining a press-formed product according to Embodiment 1, FIG. 2 is a cross-sectional view taken along line II-II in FIG. 1, and FIG. 3 is a cross-sectional view taken along line III-III in FIG. It is.

  The press-formed product (part) 120 according to Embodiment 1 is obtained by press-molding a blank (preliminary body), has a hat-shaped open section, and extends in the longitudinal direction (hat-shaped open section). A direction) Y-shaped bent portion is provided. The bent portion includes an inner wall portion 124A that is curved, an outer wall portion 124B that is spaced from the inner wall portion 124A and protrudes in an arc shape, an end portion of the inner wall portion 124A, and an outer wall portion 124B. And a connecting wall portion 126 that connects the end portions. The connecting wall 126 is flat with respect to a direction orthogonal to the longitudinal direction Y.

  The length of the press-formed product 120 along the longitudinal direction Y is larger than the length in the circumferential direction P orthogonal to the longitudinal direction Y (the total length of the wall portions 124A and 124B and the connecting wall portion 126). The corner portion that is located at the boundary between the wall portions 124A and 124B and the connecting wall portion 126 and connects the wall portions 124A and 124B and the connecting wall portion 126 has an arc shape, and the wall portions 124A and 124B and the connecting wall portion 126 are connected to each other. Are connected continuously and smoothly.

  The bent portion of the press-formed product 120 has a thickened region (a portion where the plate thickness is increased) 137 disposed in a part of the connecting wall portion 126 adjacent to the inner wall portion 124A. The plate thickness of the thickened region 137 is increased by press molding as compared with the plate thickness before press molding, and is larger than the thickness of the peripheral portion of the thickened region 137.

  The rigidity or strength of the press-formed product 120 is ensured by the thickened region 137, and the thickened region 137 is not the entire bent portion but is partial, so that the press-formed product 120 can be easily reduced in weight. It is possible. Moreover, since the thickness increase area | region 137 is formed by the press molding which has favorable productivity compared with the tailored blank to which butt welding is applied, manufacturing cost is reduced. Therefore, it is possible to reduce the weight and the manufacturing cost of the press-formed product 120 having a hat-shaped open section having a bent portion.

  Moreover, since the hardness of the thickening area | region 137 is larger than the hardness of a peripheral part by the work hardening by press molding, it can apply to the use for which hardness is required.

  The open cross section of the press-formed product 120 is not limited to a hat shape in which the wall portions 124A and 124B are positioned substantially parallel to each other and the connecting wall portion 126 and the wall portions 124A and 124B are substantially flat. A configuration in which 124B is inclined in a crossing direction, a configuration in which the lengths of the wall portions 124A and 124B are different, and a configuration in which the connecting wall portion 126 and / or the wall portions 124A and 124B are curved are included. Further, the present invention can be applied to a press-formed product that does not have the outer wall portion 124B and has an L-shaped open cross section. The L-shape is not limited to the form in which the angle on the inner side (the minor angle side) is 90 degrees, and an obtuse angle of less than 90 degrees or exceeding 90 degrees can be applied. The bent portion of the press-formed product 120 is not limited to an L shape, and may be, for example, a C shape, an acute angle shape, or a gentle arc shape.

  The blank for manufacturing the press-formed product 120 is manufactured by press-forming a rolled material, and the inner wall portion 124A extends and is positioned at the flange portion. Since it is easy to improve productivity by press molding, it is possible to obtain a low-cost press-molded product by reducing the manufacturing cost of the blank 100 that is a material.

  In this case, the thickened region 137 is a part of the connecting wall portion 126 adjacent to the inner wall portion 124A, and is located in the vicinity of the root where it is difficult to ensure strength or rigidity in the extending flange portion. The strength or rigidity can be easily secured. In addition, a blank is not limited to shape | molding from a rolling material, For example, it is also possible to apply a cast product.

  FIG. 4 is a perspective view for explaining a suspension component to which the press-formed product according to Embodiment 1 is applied.

  The suspension component 140 has an upper side member and a lower side member that have a hollow cross section and whose edges are welded to each other. The upper side member and the lower side member are long objects having a hat-shaped open cross section, and extend to the bent portion and have a flange portion. Therefore, the suspension part 140 can be efficiently reduced in weight and manufacturing cost can be efficiently achieved by applying the thickened region 137 to the local portion 142 that requires rigidity or strength near the root of the extending flange portion. Is possible.

  The press-formed product is not limited to a form applied to a suspension component, and can be applied to other vehicle structural members. Other structural members for vehicles are frame main parts, such as link parts, bracket parts, side sill outer reinforcement, and ladder members, for example.

  5 is a perspective view for explaining the blank according to the first embodiment, FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 5, and FIG. 7 is an apparatus for manufacturing a press-formed product according to the first embodiment. FIG. 8 is a cross-sectional view taken along line VIII-VIII in FIG. 7, and FIG. 9 is an enlarged view of a main part in FIG.

  The blank 100 according to Embodiment 1 is preformed, for example, by press-molding a sheet-like rolled material in advance, and its shape substantially corresponds to the shape of the press-formed product 120, and is shown in FIG. As shown, it has a hat-shaped open cross section and is provided with an L-shaped bent portion in the longitudinal direction Y.

  The bent portion includes an inner wall portion 104A that is curved, an outer wall portion 104B that is spaced apart from the inner wall portion 104A and protrudes in an arc shape, an end portion of the inner wall portion 104A, and an outer wall portion 104B. And a connecting wall portion 106 that connects the end portions. The connecting wall 106 is flat with respect to a direction orthogonal to the longitudinal direction Y. The corner portion that is located at the boundary between the wall portions 104A, 104B and the connecting wall portion 106 and connects the wall portions 104A, 104B and the connecting wall portion 106 has an arc shape, and the wall portions 104A, 104B, the connecting wall portion 106, Are connected continuously and smoothly.

  At the center of the bent portion of the blank 100, there is a protruding portion 114 protruding from the outer surface side of the inner wall portion 104A. The overhanging portion 114 constitutes a circumferential extension portion, and the circumferential length of the section in the circumferential direction P at the center of the bent portion is longer than the circumferential length of the section in the circumferential direction P at the peripheral portion. The protrusion 114 is formed to easily generate a material flow that causes an increase in plate thickness.

  The protrusion amount (size) E of the protruding protrusion 114 is preferably set in consideration of the indentation ratio. The indentation ratio is obtained by reducing the circumferential length of the circumferential region in the planned thickness increase region (the portion where the plate thickness is increased) by the sectional circumferential length of the circumferential region in the increased thickness region 137 of the press molded product. This is a value divided by the circumferential length of the circumferential region in the thickening region 137. In other words, since the indentation ratio corresponds to the material flow rate, if the indentation ratio is set large, the effect of increasing the wall thickness is improved. However, if the indentation ratio is set too large, wrinkles are excessively generated during press molding, and buckling occurs. Therefore, it is preferable to set the protruding amount E of the extended portion so that the pushing ratio does not become excessive in order to avoid the occurrence of buckling.

  Next, a press-formed product manufacturing apparatus according to Embodiment 1 will be described.

  The apparatus for manufacturing a press-formed product according to Embodiment 1 is used for manufacturing the press-formed product 120 from the blank 100, and has a forming die on which the blank 100 is arranged and clamped. As shown in FIGS. 7 and 8, the press mold has a lower die (punch portion) 170 disposed inside the blank 100 and an upper die (die portion) disposed outside the blank 100. .

  The upper mold has a fixed mold 160 and a movable mold 180 that is spaced from and opposed to the fixed mold 160. The fixed mold 160 has an L-shaped bent portion, and the bent portion has a movable portion. A movable mold insertion recess 164 into which the mold 180 is introduced is provided. The fixed mold 160 and the movable mold 180 are integrally provided with a cavity surface corresponding to the outer surface shape of the press-formed product 120.

  The fixed mold 160 has a comb-like uneven portion 166. The concavo-convex portion 166 is disposed in a movable insertion recess 164 that is an end surface facing the movable die 180.

  The cavity surface of the fixed die 160 is perpendicular to the pressing portion corresponding to the connecting wall portion 126 of the press-molded product 120 and the inner wall portion 124A of the press-molded product 120 except for the portion where the movable die insertion recess 164 is disposed. The wall portion 162A and the vertical wall portion 162B corresponding to the outer wall portion 124B of the press-formed product 120 are included. On the other hand, the cavity surface of the bent portion in which the movable insertion recess 164 is disposed has a pressing portion corresponding to a part of the connecting wall portion 126 of the press-formed product 120 and a vertical wall corresponding to the outer wall portion 124B of the press-formed product 120. The outer wall 104B of the blank 100 and a part of the connecting wall 106 adjacent to the outer wall 104B are pressed in cooperation with the lower mold 170.

  The movable mold 180 is set so as to be able to approach and move away from the movable mold insertion recess 164 of the fixed mold 160, and has a comb-shaped uneven portion 186 disposed on an end surface facing the fixed mold 160. The concavo-convex portion 186 is set so as to be freely engageable with the concavo-convex portion 166 of the fixed mold 160. The gap between the end face of the fixed mold 160 and the end face of the movable mold 180 corresponds to the pushing distance L (see FIG. 9), and is a variable gap that changes according to the mold clamping (pushing) operation of the movable mold 180. is there.

  The cavity surface of the movable mold 180 occupies the vertical wall portion 182 corresponding to the inner wall portion 124 </ b> A in the bent portion of the press-molded product 120 and a part of the connecting wall portion 126 of the press-molded product 120 (the pressing portion of the fixed mold 160 occupies it). It has a pressing part corresponding to the remaining part excluding the part. Accordingly, a part of the connecting wall portion 106 adjacent to the inner wall portion 104 </ b> A of the blank 100 is pressed in cooperation with the lower die 170, and the protruding portion of the inner wall portion 104 </ b> A is moved relative to the fixed die 160. It is possible to clamp 114 by pressing 114. Since it protrudes from the outer surface of the overhang part 114 and the connecting wall part 106, it is easy to flow the material by pushing.

  Regarding the fixed mold 160 and the movable mold 180, the bent part that is located at the boundary between the pressing part and the vertical wall part and connects the pressing part and the vertical wall part is curved, and the pressing part and the vertical wall part are continuous. Connected smoothly and smoothly.

  The lower mold 170 has a cavity surface corresponding to the inner surface shape of the press-formed product 120. The cavity surface of the lower mold 170 has a pressing portion 172 corresponding to the connecting wall portion 126 of the press-molded product 120 and a vertical wall portion corresponding to the wall portions 124A and 124B of the press-molded product 120.

  The pressing portion 172 of the lower mold 170 has a recessed portion 172A and a raised portion 172B. The indented portion 172A is disposed so as to be opposed to the planned thickness increase portion of the connecting wall portion 106 in the bent portion of the blank 100 disposed in the lower mold 170. The raised portion 172 </ b> B is disposed so as to face the non-thickening planned portion of the connecting wall portion 106. The bent part that is located at the boundary between the pressing part 172 and the vertical wall part and connects the pressing part 172 and the vertical wall part has an arc shape, and the pressing part and the vertical wall part are connected continuously and smoothly. ing.

  The recessed portion 172A of the lower mold 170 is set so that the sectional thickness of the cavity at the time of mold clamping is larger than the plate thickness of the blank 100. That is, the sectional thickness of the cavity in the bent portion formed by the lower die 170 and the movable die 180 at the time of mold clamping is at least a plate thickness of a part of the connecting wall portion 106 adjacent to the inner wall portion 104A. It is set larger.

  Therefore, in the middle of the mold clamping operation of the mold, the vertical wall portion 182 of the movable die 180 pushes the inner wall portion 104A in the bent portion of the blank 100 to generate a material flow, and at least in the inner wall portion 104A. The plate thickness of a part of the adjacent connecting wall portion 106 can be increased as compared with the plate thickness before the clamping operation. As a result, the press-formed product 120 is manufactured. Therefore, it is possible to reduce the weight and the manufacturing cost of the press-formed product 120 having a hat-shaped open section having a bent portion.

  The connecting wall portion 106 in the bent portion of the blank 100 is flat with respect to the direction orthogonal to the longitudinal direction Y, and the pushing direction of the movable mold 180 coincides with the direction orthogonal to the longitudinal direction Y. Since the connecting wall portion 106 is a surface parallel to the pushing direction, the surface rigidity when pushing the inner wall portion 104A is improved, and buckling is suppressed. Therefore, since the generation of defective products can be avoided, it is possible to reduce the cost of manufactured press-formed products.

Due to the presence of the concavo-convex portion 166 of the fixed mold 160 and the concavo-convex portion 186 of the movable mold 180, a gap is formed between the end face of the fixed mold 160 and the end face of the movable mold 180 corresponding to the pushing distance L of the movable mold 180. Spaces S ₁ and S ₂ (see FIG. 9) are reduced, and buckling of the connecting wall portion due to material outflow from the variable gap is suppressed. Therefore, it is possible to reduce the cost of the manufactured press-formed product 120 by avoiding the generation of defective products. In addition, when the mold clamping operation is completed, the uneven portion 166 of the fixed mold 160 and the uneven portion 186 of the movable mold 180 are integrally formed to form a continuous cavity surface. Generation | occurrence | production of the malfunction that a crack, a trace, or a hollow part is formed in a wall part outer surface is suppressed, and the fall of the external appearance quality of the press molded product 120 manufactured is avoided.

  As the concave portions and the width W of the convex portions constituting the concave and convex portions 166 and 186 increase, the buckling suppression effect decreases, while as the concave portion 166 and 186 decreases, the formation cost of the concave and convex portions 166 and 186 increases. The plate thickness of the blank 100 corresponds to the rigidity of the connecting wall portion 106 and affects the occurrence of buckling. Therefore, the width W is preferably set appropriately in consideration of the buckling suppressing effect, the formation cost of the uneven portions 166 and 186, the thickness of the blank 100, and the like.

  The blank 100 placed in the mold and clamped is manufactured by press molding, and it is easy to improve the productivity. Therefore, by reducing the manufacturing cost of the blank 100 as a material, the cost can be reduced. It is possible to obtain a press-formed product. Further, the portion where the plate thickness is increased is a part of the connecting wall portion 106 adjacent to the inner wall portion 104A, and is located in the vicinity of the root where it is difficult to secure strength or rigidity in the extended flange portion. The strength or rigidity of the extending flange portion can be easily ensured.

  Next, a method for manufacturing a press-formed product according to Embodiment 1 will be described.

  FIG. 10 is a cross-sectional view for explaining an arrangement step in the method for manufacturing a press-formed product according to Embodiment 1, and FIG. 11 is a diagram for explaining the middle of the mold clamping operation in the thickening step following FIG. FIG. 12 is a plan view for explaining the completion of the mold clamping operation following FIG. 10, and FIG. 13 is a cross-sectional view for explaining the completion of the mold clamping operation following FIG.

  The method for manufacturing a press-formed product according to Embodiment 1 includes a preparation process, an arrangement process, and a thickness increasing process. In the preparation process, a blank 100 is prepared. In the placement step, the blank 100 is placed in the mold. In the thickening step, the material flow is generated by pushing the inner wall portion 104A in the bent portion of the blank 100 by the molding die during the mold clamping operation of the molding die, and at least adjacent to the inner wall portion 104A. The plate thickness of a part of the connecting wall 106 is increased compared to the plate thickness before the fastening operation. Thereby, the press-formed product 120 is manufactured. Therefore, it is possible to reduce the weight and the manufacturing cost of the press-formed product 120 having a hat-shaped open section having a bent portion.

  More specifically, first, as shown in FIG. 10, the blank 100 is placed on the lower mold 170. The connecting wall portion 106 in the bent portion of the blank 100 is supported by the raised portion 172B of the lower mold 170, and the outer wall portion 104B is in contact with the vertical wall portion of the lower mold 170.

  An upper fixed mold 160 is disposed outside the blank 100. The connecting wall portion 106 in the bent portion of the blank 100 is pressed toward the raised portion 172B of the lower die 170 by the pressing portion of the fixed die 160, and the outer wall portion 104B is pressed by the vertical wall portion 162B of the fixed die 160. It is pressed toward the vertical wall.

  The upper movable mold 180 is disposed on the extending flange side of the bent portion of the blank 100. At this time, the variable gap between the end face of the fixed mold 160 and the end face of the movable mold 180 is positioned so as to be the pushing distance L (see FIG. 9). The pressing part of the movable mold 180 abuts a part of the connecting wall part 106 (the remaining part excluding the part occupied by the pressing part of the fixed mold 160), and the vertical wall part 182 contacts the protruding part 114 of the inner wall part 104A. Touch.

When the movable mold 180 is driven and moves toward the fixed mold 160, the mold clamping operation is started. The variable gap between the end face of the fixed mold 160 and the end face of the movable mold 180 is formed by the spaces S ₁ and S ₂ formed by the presence of the concavo-convex part 166 of the fixed mold 160 and the concavo-convex part 186 of the movable mold 180 (FIG. 11). Reference) is reduced, and buckling of the connecting wall portion due to material outflow from the variable gap is suppressed.

  The vertical wall portion 182 of the movable mold 180 generates a material flow by pushing the protruding portion 114 of the inner wall portion 104A. Since the protruding portion 114 protrudes from the outer surface of the inner wall portion 104A, it is easy to flow the material by pushing. The connecting wall portion 106 in the bent portion of the blank 100 is flat with respect to the direction orthogonal to the longitudinal direction Y, and the pushing direction of the movable mold 180 coincides with the direction orthogonal to the longitudinal direction Y. Therefore, since the connecting wall portion 106 is a surface parallel to the pushing direction, the surface rigidity when pushing the inner wall portion 104A is improved, and buckling is suppressed. Therefore, since the generation of defective products can be avoided, it is possible to reduce the cost of manufactured press-formed products.

  Next, the movable mold 180 further moves toward the fixed mold 160 until the concave and convex portion 186 of the movable mold 180 and the concave and convex portion 166 of the fixed mold 160 are integrated to form a continuous cavity surface (see FIG. 12). As a result, the cavity surfaces of the movable mold 180, the fixed mold 160, and the lower mold 170 are integrated to match the inner surface shape and outer surface shape of the press-molded product 120, and the mold clamping operation is completed.

  Due to the presence of the recessed portion 172A of the lower mold 170, a part of the connecting wall 106 adjacent to the inner wall 104A where the protrusion 114 is disposed has a cavity cross-sectional thickness larger than the plate thickness of the blank 100 at the time of clamping. It is set to be. Accordingly, the material flow caused by pushing the protruding portion 114 of the inner wall portion 104A can increase the plate thickness of a part of the connecting wall portion 106 as compared with the plate thickness before the mold clamping operation. (See FIG. 13). As a result, the press-formed product 120 is manufactured. Therefore, it is possible to reduce the weight and the manufacturing cost of the press-formed product 120 having a hat-shaped open section having a bent portion.

  FIG. 14 is a plan view for explaining the first modification according to the first embodiment.

  The concavo-convex portion 166 of the fixed mold 160 and the concavo-convex portion 186 of the movable mold 180 can be appropriately omitted as shown in FIG. 14 in consideration of the rigidity of the blank 100 to be applied, the indentation ratio, and the like.

  FIG. 15 is a cross-sectional view for explaining the second modification according to the first embodiment.

  The portion where the plate thickness is increased is not limited to a part of the connecting wall portion 106 adjacent to the inner wall portion 104A of the bent portion, and the plate thickness of the inner wall portion 104A itself can be increased at the same time. In this case, the sectional thickness of the cavity formed by the vertical wall portion 182 of the movable mold 180 and the vertical wall portion adjacent to the recessed portion 172A of the lower mold 170 becomes larger than the plate thickness of the blank 100 at the time of mold clamping. Set as follows.

  FIG. 16 is a perspective view for explaining the third modification according to the first embodiment.

  The protrusion 114 is not limited to a single one, and a plurality of the protrusions 114 can be arranged separately along the longitudinal direction Y. For example, as shown in FIG. 16, when three projecting portions 114 </ b> A to 141 </ b> C are arranged on the inner wall portion 104 </ b> A of the bent portion of the blank 100, press forming having three thickening regions 137 </ b> A, 137 </ b> B, 137 </ b> C. Product 120 is obtained. In this case, it is possible to expand the application range of the press-formed product 120 to be manufactured.

  As described above, in the press-formed product according to Embodiment 1, the plate thickness before the press molding is determined so that the thickness of at least a part of the connecting wall portion adjacent to the inner wall portion in the bent portion in the longitudinal direction is the press-formed. The thickness of the portion where the thickness is increased and the thickness is increased compared to the thickness is larger than the thickness of the peripheral portion of the portion. The rigidity or strength of the press-formed product is ensured by the portion where the plate thickness is increased, and the portion where the plate thickness is increased is not the whole of the bent portion but is partial, so It is possible to easily reduce the weight. Moreover, since the site | part where the plate | board thickness is increasing is formed by press molding which has favorable productivity compared with the tailored blank to which butt welding is applied, manufacturing cost is reduced. Therefore, it is possible to reduce the weight and manufacturing cost of a press-formed product having a hat-shaped open cross section having a bent portion.

  Since the hardness of the portion where the plate thickness is increased is greater than the hardness of the peripheral portion by work hardening by press molding, it can be applied to applications that require hardness.

  The press-molded product is manufactured from a blank manufactured by press molding, and the inner wall portion extends and is positioned at the flange portion. Since it is easy to improve productivity in press molding, it is possible to obtain a low-cost press-molded product by reducing the manufacturing cost of the blank that is the material. Further, the portion where the plate thickness is increased is a part of the connecting wall portion adjacent to the inner wall portion, and is located in the vicinity of the root where it is difficult to ensure strength or rigidity in the extending flange portion. The strength or rigidity of the portion can be easily ensured.

  In the apparatus for manufacturing a press-formed product according to Embodiment 1, the press-formed product is manufactured. Therefore, it is possible to reduce the weight and manufacturing cost of a press-formed product having a hat-shaped open cross section having a bent portion.

  The blank which is placed in a mold having an upper mold (a fixed mold and a movable mold) and a lower mold and clamped has a protrusion, and the protrusion protrudes from the outer surface of the inner wall. It is easy to make the material flow by pushing.

  The fixed mold and the movable mold have comb-shaped concavo-convex portions that are arranged on opposite end faces and can be fitted to each other. As a result, the space formed in the variable gap corresponding to the indentation distance between the end face of the fixed mold and the end face of the movable mold is reduced, and the buckling of the connecting wall portion due to the material outflow from the variable gap is suppressed. The Therefore, since the generation of defective products can be avoided, it is possible to reduce the cost of manufactured press-formed products. In addition, when the mold clamping operation is completed, the concavo-convex portion of the fixed mold and the concavo-convex portion of the movable mold are integrally formed to form a continuous cavity surface. Generation | occurrence | production of the malfunction which a crack, a trace, or a hollow part is formed is suppressed, and the fall of the external appearance quality of the press molded product manufactured is avoided.

  The blank that is placed in the mold and clamped is manufactured by press molding, and the inner wall portion extends and is positioned at the flange portion. Since it is easy to improve productivity in press molding, it is possible to obtain a low-cost press-molded product by reducing the manufacturing cost of the blank that is the material. Further, the portion where the plate thickness is increased is a part of the connecting wall portion adjacent to the inner wall portion, and is located in the vicinity of the root where it is difficult to ensure strength or rigidity in the extending flange portion. The strength or rigidity of the portion can be easily ensured.

  The blank placed in the mold and clamped has a hat-shaped open cross section, and the connecting wall portion of the bent portion is flat in the direction perpendicular to the longitudinal direction Y, and the movable die is pushed in. Corresponds to the direction orthogonal to the longitudinal direction Y. Therefore, the connecting wall portion becomes a surface parallel to the pushing direction of the inner wall portion, so that the surface rigidity when pushing the inner wall portion is improved and buckling is suppressed. Therefore, since the generation of defective products can be avoided, it is possible to reduce the cost of manufactured press-formed products.

  In the method for manufacturing a press-formed product according to Embodiment 1, the press-formed product is manufactured. Therefore, it is possible to reduce the weight and manufacturing cost of a press-formed product having a hat-shaped open cross section having a bent portion.

  Since the blank prepared in the preparation step has a protruding portion, and the protruding portion protrudes from the outer surface of the inner wall portion, it is easy to flow the material by pressing. In addition, when a plurality of protrusions are arranged apart from each other in the longitudinal direction, a press-formed product in which a plurality of portions where the plate thickness is increased is arranged apart from each other in the longitudinal direction is manufactured. Therefore, it is possible to expand the application range of manufactured press-formed products.

  The blank prepared in the preparation process is manufactured by press molding, and the inner wall portion extends and is positioned at the flange portion. Since it is easy to improve productivity in press molding, it is possible to obtain a low-cost press-molded product by reducing the manufacturing cost of the blank that is the material. Further, the portion where the plate thickness is increased is a part of the connecting wall portion adjacent to the inner wall portion, and is located in the vicinity of the root where it is difficult to ensure strength or rigidity in the extending flange portion. The strength or rigidity of the portion can be easily ensured.

  The blank prepared in the preparation step has a hat-shaped open cross section, the connecting wall portion of the bent portion is flat with respect to the direction orthogonal to the longitudinal direction Y, and the movable pushing direction is the longitudinal direction. It coincides with the direction orthogonal to Y. Therefore, the connecting wall portion becomes a surface parallel to the pushing direction of the inner wall portion, so that the surface rigidity when pushing the inner wall portion in the thickening step is improved, and buckling is suppressed. Therefore, since the generation of defective products can be avoided, it is possible to reduce the cost of manufactured press-formed products.

  Next, a second embodiment will be described. In the following, members having the same functions as those in the first embodiment are denoted by similar reference numerals, and the description thereof is omitted to avoid duplication.

  FIG. 17 is a perspective view for explaining a blank and a press-formed product according to the second embodiment, FIG. 18 is a cross-sectional view for explaining the press-formed product manufacturing apparatus according to the second embodiment, and FIG. FIG. 10 is a cross-sectional view for explaining the completion of the mold clamping operation in the thickening step in the method for manufacturing a press-formed product according to Embodiment 2.

  The second embodiment is generally different from the first embodiment in that wrinkle generation suppressing means is arranged on the connecting wall portion to suppress generation of wrinkles that cause buckling.

  As shown in FIG. 17, the blank 200 according to the second embodiment has a hat-shaped open cross section and is provided with a bent portion, and the bent portion includes an inner wall portion 204 </ b> A that is curved and an inner side. The outer wall portion 204B is spaced apart from the wall portion 204A and protrudes in an arc shape, and the connecting wall portion 206 connects the end portion of the inner wall portion 204A and the end portion of the outer wall portion 204B.

  At the center of the bent portion of the blank 200, there is a protruding portion 214 protruding from the outer surface side of the inner wall portion 204A. The connecting wall portion 206 adjacent to the protruding portion 214 has an embossed portion (wrinkle generation suppressing means) 215. The embossed portion 215 is a three-dimensional concave portion disposed on the connecting wall portion 206, and has improved strength or rigidity by embossing.

  The press-formed product 220 according to Embodiment 2 has a hat-shaped open cross section and is provided with a bent portion, and the bent portion is spaced from the curved inner wall portion 224A and the inner wall portion 224A. And an outer wall portion 224B that protrudes in an arc shape and a connecting wall portion 226 that connects the end portion of the inner wall portion 224A and the end portion of the outer wall portion 204B.

  The connecting wall portion 226 at the center of the bent portion of the press-formed product 220 has a thickened region 237 adjacent to the inner wall portion 224A and an embossed portion 215 that remains even after the press working. The embossed portion 215 has a rectangular emboss shape and partially overlaps the thickened region 237.

  When manufacturing the press-molded product 220, the connecting wall portion 206 of the blank 200 is improved in strength or rigidity due to the presence of the embossed portion 215, so that excessive generation of wrinkles in the connecting wall portion 206 is suppressed and buckling is performed. Can be avoided. Therefore, since the generation of defective products is suppressed, it is possible to reduce the cost of the manufactured press-formed product 220. That is, the press-molded product 220 is inexpensive. Further, as will be described later, the ridge lines facing each other in the embossed shape are parallel to the pressing direction of the inner wall portion by the molding die, and generation of wrinkles due to deformation of the embossed portion 215 is suppressed, which is good. Appearance quality is good.

  As shown in FIG. 18, the apparatus for manufacturing a press-formed product according to the second embodiment is substantially the same as the apparatus for manufacturing a press-formed product according to the first embodiment except for the shape of the cavity surface. An upper die (die portion) having 260 and a movable die 280 and a lower die (punch portion) 270 are included. The fixed mold 260 and the movable mold 280 have comb-shaped concavo-convex portions 266 and 286 that are arranged on opposite end faces and can be fitted to each other. The pressing portion 272 of the lower mold 270 has a recessed portion 272A and a raised portion 272B.

  The recessed portion 272 </ b> A is disposed so as to face the planned thickness increase portion of the connection wall portion 206 in the bent portion of the blank 200 disposed in the lower mold 220. Since the embossed portion 215 of the blank 200 remains in the press-molded product 220 and partially overlaps the thickened region 237, the shape of the recessed portion 272A is a three-dimensional shape portion corresponding to the embossed portion 215. Have.

  The movable mold 280 is set so as to push in the inner wall portion 204A in parallel to the ridge lines of the embossed portion 215 facing each other in the embossed shape. Therefore, since the generation of wrinkles due to the deformation of the embossed portion 215 is suppressed, a press-formed product having good appearance quality can be obtained.

  In the method for manufacturing a press-formed product according to Embodiment 2, the blank 200 prepared in the preparation process has an embossed portion 215. The embossed portion 215 is located on the connecting wall portion 206 adjacent to the protruding portion 214 in the inner wall portion 204A of the bent portion of the blank 200, and improves the strength or rigidity of the connecting wall portion 206.

  Therefore, when the material flow is generated by pushing the protrusion 214 with the movable mold 280 in the thickness increasing step, excessive generation of wrinkles in the connecting wall portion can be avoided (see FIG. 19). Therefore, buckling is suppressed and generation of defective products can be avoided, so that the cost of manufactured press-molded products can be reduced. That is, the press-molded product 220 is inexpensive. In addition, since the ridge lines of the embossed portion 215 facing each other in the embossed shape are parallel to the pushing direction of the inner wall portion, generation of wrinkles due to deformation of the embossed portion 215 is suppressed. Therefore, a press-formed product having good appearance quality can be obtained.

  Further, the wrinkle generation suppressing means is not limited to being configured by the embossed portion, but the embossed portion is preferable because the wrinkle generation suppressing means can be easily configured.

  FIG. 20 is a perspective view for explaining the first modification according to the second embodiment, and FIG. 21 is a cross-sectional view for explaining the first modification according to the second embodiment, showing an arrangement process. FIG. 22 is a cross-sectional view for explaining the first modification according to the second embodiment, and shows the completion of the mold clamping operation in the thickening step.

  The size and number of the embossed portions 215 can be set as appropriate. For example, as shown in FIG. 20, five small embossed portions 215 </ b> A to 215 </ b> E can be disposed on the connecting wall portion 206 adjacent to the protruding portion 214 in the inner wall portion 204 </ b> A of the bent portion of the blank 200. It is.

  At this time, when the shape of the recessed portion 272A of the lower mold 270 is set so as not to have a three-dimensional shape portion corresponding to the embossed portion 215, as shown in FIGS. 21 and 22, the embossed portion 215 is It disappears when the mold clamping operation is completed. Accordingly, it is possible to obtain a press-molded product 220 in which the embossed portion 215 does not remain, and it is possible to further expand the application range of the manufactured press-molded product 220.

  As described above, the press-formed product according to Embodiment 2 has the embossed portion adjacent to the inner wall portion in the connecting wall portion in the bent portion. When manufacturing a press-molded product, since the strength or rigidity of the connecting wall portion is improved by the presence of the embossed portion, excessive generation of wrinkles in the connecting wall portion is suppressed, and buckling is avoided. Therefore, since the generation of defective products is suppressed, the cost of manufactured press-molded products can be reduced. That is, the press-formed product is inexpensive. Also, the ridge lines of the embossed part facing each other in the embossed shape are parallel to the pushing direction of the inner wall part, and during the manufacturing, the generation of wrinkles due to deformation of the embossed part is suppressed, which is favorable. Appearance quality.

  In the device for manufacturing a press-formed product according to the second embodiment, the movable die is set so as to push the inner wall portion in parallel with each other ridgeline of the embossed shape facing each other in the embossed portion. Therefore, since the generation of wrinkles due to deformation of the embossed portion is suppressed, a press-formed product having a good appearance quality can be obtained.

  In the manufacturing method of the press-formed product according to Embodiment 2, the connecting wall portion adjacent to the inner wall portion in the bent portion of the blank prepared in the preparation step has wrinkle generation suppressing means, and the thickness increasing step However, since excessive generation of wrinkles in the connecting wall portion is avoided, buckling is suppressed. Therefore, since the generation of defective products can be avoided, it is possible to reduce the cost of manufactured press-formed products. In addition, since the ridge lines facing each other in the embossed portion in the embossed portion are parallel to the pushing direction of the inner wall portion, the generation of wrinkles due to the deformation of the embossed portion is suppressed. Therefore, a press-formed product having good appearance quality can be obtained.

  The wrinkle generation suppressing means includes an embossed portion formed in the connecting wall portion adjacent to the inner wall portion, and the connecting wall portion is improved in strength or rigidity due to the presence of the embossed portion. Excessive generation of can be avoided. That is, the wrinkle generation suppressing means can be easily configured by the embossed portion.

  Next, a third embodiment will be described.

  FIG. 23 is a perspective view for explaining the blank and the press-formed product according to the third embodiment, and FIGS. 24, 25, and 26 are diagrams for explaining the press-formed product manufacturing apparatus according to the third embodiment. FIG. 27, FIG. 28 and FIG. 29 are a sectional view, a plan view and a rear view for explaining the completion of the mold clamping operation according to the third embodiment.

  The third embodiment is generally different from the first embodiment in that wrinkles that cause buckling are suppressed by changing the configuration of the lower mold.

  As shown in FIG. 23, the blank 300 according to the third embodiment has a hat-shaped open cross section and is provided with a bent portion, and the bent portion includes an inner wall portion 304A that is curved and an inner side. The outer wall portion 304B is spaced apart from the wall portion 304A and protrudes in an arc shape, and the connecting wall portion 306 connects the end portion of the inner wall portion 304A and the end portion of the outer wall portion 304B.

  At the center of the bent portion of the blank 300, there is a protruding portion 314 protruding from the outer surface side of the inner wall portion 304A. In addition, since generation | occurrence | production of the wrinkle which causes buckling is suppressed by changing the structure of a lower mold | type, the protrusion amount of the overhang | projection part 314 is set larger than the protrusion amount of the overhang | projection part 114 which concerns on Embodiment 1. FIG. ing.

  A press-molded product 320 obtained by press-molding the blank 300 has a hat-shaped open cross section and is provided with a bent portion, and the bent portion includes a curved inner wall portion 324A and an inner wall portion 324A. An outer wall 324B that is spaced apart from the outer wall and protrudes in an arc shape, and a connecting wall 326 that connects the end of the inner wall 324A and the end of the outer wall 324B.

  The connecting wall portion 326 at the center of the bent portion of the press-formed product 320 has a thickened region 337 adjacent to the inner wall portion 324A. Since the protruding amount of the protruding portion 314 in the blank 300 is set larger than the protruding amount of the protruding portion 114 according to the first embodiment, the increased amount of the thickened region 237 is the increased thickness region according to the first embodiment. It is larger than the increase in thickness of 137.

  As shown in FIG. 24, the apparatus for manufacturing a press-formed product according to the third embodiment includes an upper mold (die part) having a fixed mold 360 and a movable mold 380, and a lower mold having a fixed mold 370 and a movable mold 390. (Punch part).

  The upper fixed mold 360 and the movable mold 380 (hereinafter referred to as the upper fixed mold 360 and the upper movable mold 380) are arranged on opposite end faces and can be fitted to each other as shown in FIG. Comb-like uneven portions 366 and 386 are provided.

  The cavity surface of the upper fixed die 360 is a vertical portion corresponding to the pressing portion corresponding to the connecting wall portion 326 of the press-formed product 320 and the inner wall portion 324A of the press-formed product 320 except for the portion where the movable die insertion recess is disposed. The wall portion 362A and the vertical wall portion 362B corresponding to the outer wall portion 324B of the press-formed product 320 are provided. On the other hand, the cavity surface of the bent portion in which the movable insertion recess is disposed has a pressing portion corresponding to a part of the connecting wall portion 326 of the press-formed product 320 and a vertical wall portion corresponding to the outer wall portion 324B of the press-formed product 320. 362B.

  The cavity surface of the upper movable die 380 includes a vertical wall portion 382 corresponding to the inner wall portion 324A in the bent portion of the press-formed product 320, and a part of the connecting wall portion 326 of the press-formed product 320 (the pressing portion of the upper fixed die 360). And a pressing portion corresponding to the remaining portion excluding the portion occupied by.

  As shown in FIG. 26, the lower fixed die 370 (hereinafter referred to as the lower fixed die 370) has an L-shaped bent portion, and the bent portion includes a movable die 390 (hereinafter referred to as the lower die 370). , Which is referred to by the lower movable mold 390). The lower fixed mold 370 and the lower movable mold 390 are integrally provided with a cavity surface having a hat-shaped open cross section corresponding to the inner surface shape of the press-formed product 320.

  The lower fixed mold 370 has a comb-like uneven portion 376. The concavo-convex portion 376 is disposed in a movable insertion recess that is an end surface facing the lower movable mold 390.

  The cavity surface of the lower fixed die 370 is a vertical portion corresponding to the pressing portion corresponding to the connecting wall portion 326 of the press-formed product 320 and the inner wall portion 324A of the press-formed product 320 except for the portion where the movable die insertion recess is disposed. The wall portion 362A and the vertical wall portion 362B corresponding to the outer wall portion 324B of the press-formed product 320 are provided. On the other hand, the cavity surface of the bent portion where the movable insertion concave portion is disposed is formed on the pressing portion (raised portion) 372B corresponding to a part of the connecting wall portion 326 of the press-formed product 320 and the outer wall portion 324B of the press-formed product 320. Used to press the outer wall 304B of the blank 300 and a portion of the connecting wall 306 adjacent to the outer wall 304B in conjunction with the upper fixed mold 360, with a corresponding vertical wall 362B.

  The lower movable mold 390 is positioned below the upper movable mold 380, is spaced apart from the lower fixed mold 370, and is used to support a part of the connecting wall portion 306 adjacent to the inner wall portion 304A. .

  The cavity surface of the lower movable die 390 includes a vertical wall portion 382 corresponding to the inner wall portion 324A in the bent portion of the press-formed product 320, and a part of the connecting wall portion 326 of the press-formed product 320 (the pressing portion of the lower fixed die 370). The remaining portion excluding the portion occupied by the pressure portion) is provided with a depression portion 372A for allowing material flow.

  The lower movable mold 390 is biased by a spring mechanism, for example, in a direction away from the lower fixed mold 370. The biasing means is not limited to the spring mechanism, and can be substituted by an actuator or a hydraulic cylinder.

  Therefore, when the upper movable mold 380 is driven and the protruding portion 314 of the inner wall portion 304A is pushed by the vertical wall portion 382 of the upper movable mold 380, the lower movable mold 390 that is in contact with the back side of the protruding portion 314. Force is transmitted to the vertical wall. Since the lower movable mold 390 is biased by the spring mechanism and is separated from the lower fixed mold 370, the lower movable mold 390 moves toward the lower fixed mold 370. That is, the movement of the upper movable mold 380 and the movement of the lower movable mold 390 are interlocked.

  As a result, the connecting wall portion 306 adjacent to the inner wall portion 304A pushed by the upper movable die 380 is increased in thickness while being supported by the lower movable die 390 that moves in conjunction with the upper movable die 380. As shown in FIG. 2, it is possible to increase the amount of pressing per molding while avoiding buckling. Since the indentation amount and the thickness increase have a proportional relationship, productivity can be improved by increasing the thickness increase per molding.

Note that the mechanism for interlocking the relative movement of the upper movable mold 380 and the relative movement of the lower movable mold 390 is not limited to the form in which the spring mechanism is applied, and for example, the upper movable mold 380 and the lower movable mold 390. Can be synchronized while being driven independently.
In addition, the lower movable mold 390 includes a pressing portion in which the indented portion 372A is disposed and a concavo-convex portion 396 disposed on an end surface facing the lower fixed mold 370. The concavo-convex portion 396 is set so as to be close to and away from the movable insertion concave portion of the lower fixed mold 370 and is set to be fitted to the concavo-convex portion 376 of the lower fixed mold 370.

The gap between the end face of the lower fixed mold 370 and the end face of the lower movable mold 390 corresponds to the pushing distance L (see FIG. 9), and changes according to the mold clamping (pushing) operation of the upper movable mold 380. It is a variable gap. Due to the presence of the concavo-convex portions 376 and 396, the spaces S ₃ and S ₄ (see FIG. 26) formed in the variable gap corresponding to the pushing distance between the end surface of the lower fixed die 370 and the end surface of the lower movable die 390 are reduced. And the buckling of the connection wall part based on the material outflow from the said variable gap is suppressed.

  Further, when the mold clamping operation is completed, as shown in FIG. 29, the concave and convex portion 376 of the lower fixed mold 370 and the concave and convex portion 396 of the lower movable mold 390 are integrated to form a continuous cavity surface. For this reason, the occurrence of defects in which scratches, marks, or dents are formed on the inner surface of the connecting wall portion of the manufactured press-formed product 320 is suppressed, and deterioration of the appearance quality of the manufactured press-formed product is avoided. As shown in FIG. 28, the concave and convex portions 366 and 386 of the upper fixed mold 360 and the upper movable mold 380 are also integrated to form a continuous cavity surface. Generation | occurrence | production of the malfunction by which a flaw, a trace, or a hollow part is formed in a wall part inner surface is suppressed, and the fall of the external appearance quality of the press molded product manufactured is avoided.

  As described above, in the apparatus for manufacturing a press-formed product according to the third embodiment, the connecting wall portion adjacent to the inner wall portion pushed by the upper movable die is moved in conjunction with the upper movable die. Since the thickness is increased while being supported by 390, it is possible to increase the amount of pressing per molding while avoiding buckling. Since the indentation amount and the thickness increase have a proportional relationship, productivity can be improved by increasing the thickness increase per molding.

  Further, the lower fixed mold and the lower movable mold have concavo-convex portions that are arranged on end surfaces facing each other and can be freely fitted, and due to the presence of the concavo-convex portions, the end surface of the lower fixed mold and the end surface of the lower movable mold The space formed in the variable gap corresponding to the pushing distance between the two is reduced, and the buckling of the connecting wall portion due to the material outflow from the variable gap is suppressed. Further, when the mold clamping operation is completed, the concave and convex portions of the lower fixed mold and the concave and convex portions of the lower movable mold 390 are integrally formed to form a continuous cavity surface. Generation | occurrence | production of the malfunction by which a flaw, a trace, or a hollow part is formed in a part inner surface is suppressed, and the fall of the external appearance quality of the press-formed product manufactured is avoided.

  Next, a fourth embodiment will be described.

  30 is a perspective view for explaining a blank and a press-formed product according to Embodiment 4, and FIG. 31 is a perspective view for explaining a suspension component to which the press-formed product according to Embodiment 4 is applied. is there.

  The fourth embodiment is generally different from the first embodiment regarding the shape of the bent portion.

  As shown in FIG. 30, the blank 400 according to the fourth embodiment has a hat-shaped open cross section and is provided with a bent portion, and the bent portion is bent three-dimensionally and curved. The inner wall 404B, the outer wall 404A that is spaced apart from the inner wall 404B and protrudes in an arc shape, and the end of the inner wall 404B and the end of the outer wall 404A are connected to each other. And a connecting wall portion 406. The center of the bent portion of the blank 400 has a protruding portion 414 that protrudes from the outer surface side of the inner wall portion 404B.

  A press-molded product 420 obtained by press-molding the blank 400 has a hat-shaped open cross section and is provided with a bent portion, and the bent portion is bent three-dimensionally and is curved. A wall 424B, an outer wall 424A that is spaced apart from the inner wall 424B and protrudes in an arc shape, and a connecting wall that connects the end of the inner wall 424B and the end of the outer wall 424A 426.

  The center of the bent portion of the press-formed product 420 has a thickened region 437. The thickened region 437 occupies the inner wall portion 424B and a part of the connecting wall portion 426 adjacent to the inner wall portion 424B. The bent portion is bent three-dimensionally, and the application range of the press-formed product can be expanded.

  For example, the suspension component 440 shown in FIG. 31 has a three-dimensional bent portion with a curved flange surface, and has a local portion 442 that requires rigidity or strength in the vicinity of the extended flange portion of the bent portion. . The local part 442 is used to fix a bracket 444 for fastening another part such as an arm. Therefore, by applying the thickened region 437 of the press-formed product 420 to the local part 442 of the suspension component 440, it is possible to ensure a good fixing strength. In particular, when welding is applied to fixing, fatigue strength is improved, which is preferable.

  32 is a cross-sectional view for explaining a press-molded product manufacturing apparatus according to Embodiment 4, FIG. 33 is a perspective view for explaining the movable mold shown in FIG. 32, and FIG. 34 is an embodiment. 4 is a cross-sectional view for explaining the completion of the mold clamping operation according to FIG.

  The press-molded product manufacturing apparatus according to the fourth embodiment is substantially the same as the press-molded product manufacturing apparatus according to the first embodiment except for the shape of the cavity surface, as shown in FIG. It has an upper mold (die part) having 460 and a movable mold 480 and a lower mold (punch part) 470. The fixed mold 460 and the movable mold 480 have comb-like concavo-convex portions 466 and 486 that are arranged on opposite end surfaces and can be fitted to each other. The pressing portion 472 of the lower mold 470 has a recessed portion 472B and a raised portion 472A.

  As shown in FIG. 33, the pressing surface for pressing the projecting portion 414 (inner wall portion 404B) in the movable mold 480 corresponds to the bent portion, is bent three-dimensionally, and is a direction orthogonal to the longitudinal direction Y. It matches. In FIG. 33, the uneven portion 486 is omitted.

  Since the pushing direction of the protruding portion 414 in the movable mold 480 coincides with the direction orthogonal to the longitudinal direction Y, the connecting wall portion 406 becomes a surface parallel to the pushing direction of the protruding portion 414. Therefore, in the thickness increasing process, the surface rigidity when pushing the protrusion 414 is improved, and buckling is suppressed. Therefore, the occurrence of defective products from the start of pressing shown in FIG. 32 to the completion of the mold clamping operation shown in FIG. 34 can be avoided, and the cost of the press-formed product to be manufactured can be reduced.

  As described above, the press-formed product according to Embodiment 4 has a hat-shaped open cross section, and its bent portion is three-dimensionally bent, so that the applicable range can be expanded.

  Further, the method and apparatus for manufacturing a press-formed product according to Embodiment 4 can manufacture the press-formed product.

  Furthermore, the pressing surface for pressing the protruding portion (inner wall portion) in the movable mold of the manufacturing apparatus corresponds to the bent portion, is bent three-dimensionally, and coincides with the direction orthogonal to the longitudinal direction Y. . Since the connecting wall portion is a surface parallel to the pushing direction of the inner wall portion, the surface rigidity when pushing the inner wall portion is improved and buckling is suppressed. Therefore, since the generation of defective products can be avoided, it is possible to reduce the cost of manufactured press-formed products.

  The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims.

  For example, by adding a pre-molding function to a press-molded product manufacturing device, it is configured to produce a press-molded product from a flat plate material (material) that is not preformed in a series of steps. Thus, workability and productivity can be improved.

  It is also possible to improve the wall-thinning efficiency by providing a suppression means for suppressing the flow of the material causing the increase of the plate thickness to the peripheral portion at the edge of the portion where the plate thickness is increased in the blank. . The suppressing means is not particularly limited as long as it has a structure that inhibits the transmission of compressive stress, and for example, a through hole, a slit, a concave portion, and a bent portion are applicable.

  The size and the number of the through holes are preferably set as appropriate according to the size and shape of the portion where the thickness of the blank is increased. It is preferable in terms of productivity and cost that the slit is formed by punching when a blank is formed from the rolled material. However, the slit can be formed separately by machining. The width and length of the slit are preferably set as appropriate according to the size and shape of the portion where the thickness of the blank is increased. After press molding, if necessary, the slit can be joined by welding or the like to ensure rigidity.

  A recessed part consists of a thin part, and is preferable at a point with little influence with respect to rigidity compared with a slit. It is preferable in terms of productivity and cost that the concave portion is formed by press molding when a blank is formed from a rolled material. However, the recesses can be formed separately by machining, or when casting is applied to the blank, the recesses can be formed collectively at the time of casting. The width and length of the recess are preferably set as appropriate according to the size and shape of the portion where the plate thickness of the blank is increased.

  The bent portion is preferable in that it has less influence on rigidity as compared with the concave portion formed of a thin portion. The cross-sectional shape of the bent portion is not particularly limited, but it is preferable to eliminate (or reduce) the residual marks in the press-formed product by making the shape easy to deform, for example, a gentle arc shape. It is preferable in terms of productivity and cost that the bent portion is formed by press molding when a blank is formed from a rolled material. However, when casting is applied to the blank, it is possible to collectively form a bent portion during casting. The size and length of the bent portion are preferably set as appropriate according to the size and shape of the portion of the blank where the plate thickness is increased.

3 is a perspective view for explaining a press-formed product according to Embodiment 1. FIG. It is sectional drawing regarding line II-II of FIG. It is sectional drawing regarding line III-III of FIG. It is a perspective view for demonstrating the suspension components to which the press-formed product which concerns on Embodiment 1 is applied. It is a perspective view for demonstrating the blank which concerns on Embodiment 1. FIG. FIG. 6 is a cross-sectional view taken along line VI-VI in FIG. 5. 5 is a plan view for explaining the press-formed product manufacturing apparatus according to Embodiment 1. FIG. It is sectional drawing regarding line VIII-VIII of FIG. It is a principal part enlarged view of FIG. 6 is a cross-sectional view for explaining an arrangement step in the method for manufacturing a press-formed product according to Embodiment 1. FIG. It is a top view for demonstrating the middle of the mold clamping operation | movement of the thickness increasing process following FIG. FIG. 11 is a plan view for explaining the completion of the mold clamping operation following FIG. 10. FIG. 11 is a cross-sectional view for explaining the completion of the mold clamping operation following FIG. 10. FIG. 10 is a plan view for explaining the first modification according to the first embodiment. FIG. 10 is a cross-sectional view for explaining a second modification according to the first embodiment. FIG. 10 is a perspective view for explaining a third modification according to the first embodiment. It is a perspective view for demonstrating the blank and press-formed product which concern on Embodiment 2. FIG. 6 is a cross-sectional view for explaining a device for manufacturing a press-formed product according to Embodiment 2. FIG. FIG. 10 is a cross-sectional view for explaining the completion of the mold clamping operation in the thickening step in the method for manufacturing a press-formed product according to Embodiment 2. FIG. 10 is a perspective view for explaining a first modification according to the second embodiment. It is sectional drawing for demonstrating the modification 1 which concerns on Embodiment 2, and has shown the arrangement | positioning process. It is sectional drawing for demonstrating the modification 1 which concerns on Embodiment 2, and has shown completion of the mold clamping operation | movement in the thickening process. It is a perspective view for demonstrating the blank and press-formed product which concern on Embodiment 3. FIG. FIG. 6 is a cross-sectional view for explaining a device for manufacturing a press-formed product according to Embodiment 3. 10 is a plan view for explaining a press-formed product manufacturing apparatus according to Embodiment 3. FIG. 10 is a rear view for explaining a press-formed product manufacturing apparatus according to Embodiment 3. FIG. 10 is a cross-sectional view for explaining the completion of the mold clamping operation according to Embodiment 3. FIG. FIG. 10 is a plan view for explaining completion of the mold clamping operation according to the third embodiment. 10 is a rear view for explaining completion of a mold clamping operation according to Embodiment 3. FIG. It is a perspective view for demonstrating the blank and press-formed product which concern on Embodiment 4. It is a perspective view for demonstrating the suspension components to which the press-formed product which concerns on Embodiment 4 is applied. FIG. 10 is a cross-sectional view for explaining a device for manufacturing a press-formed product according to Embodiment 4. It is a perspective view for demonstrating the movable type | mold shown by FIG. FIG. 10 is a cross-sectional view for explaining the completion of the mold clamping operation according to the fourth embodiment.

Explanation of symbols

100 blank (preform)
104A inner wall,
104B outer wall,
106 connecting wall,
114 (114A-114C) protrusion part,
120 press-formed products,
124A inner wall,
124B outer wall,
126 connecting wall,
137 Thickening area (137A-137C) Thickening area,
140 suspension parts,
142 local site,
160 Fixed mold (die part),
162A, 162B vertical wall,
164 movable insertion recess,
166 irregularities,
170 Lower mold (punch part),
172 pressing part,
172A Indentation site,
172B Raised site,
180 Movable type (die part),
182 vertical wall,
186 uneven part,
200 blank (preform)
204A inner wall,
204B outer side wall,
206 connecting wall,
214 protrusions,
215 (215A to 215E) embossed part,
220 press-molded products,
220 Lower mold (punch part),
224A inner wall,
224B outer wall,
226 connecting wall,
237 thickening area,
260 Fixed type (die part),
266 uneven part,
270 Lower mold,
272 pressing part,
272A Indentation site,
272B Raised site,
280 Movable type (die part),
286 irregularities,
300 blank (preform)
304A inner wall,
304B outer wall portion,
306 connecting wall,
314 protrusion,
320 Press-formed products,
324A inner wall,
324B outer wall,
326 connecting wall,
337 thickening area,
360 Upper fixed type (die part),
362A vertical wall,
362B vertical wall,
366 irregularities,
370 Lower fixed type (punch part),
372A Indentation site,
376 irregularities,
380 Upper movable type (die part),
386 irregularities,
382 vertical wall,
390 Lower movable type (punch part),
396 uneven part,
400 blank (preform)
404A outer wall,
404B inner wall,
406 connecting wall,
414 protrusion,
420 press-formed products,
424A outer wall,
424B inner wall,
426 connecting wall,
437 thickening area,
440 suspension parts,
442 local site,
444 bracket,
460 fixed mold (die part),
466 uneven part,
470 Lower mold (punch part),
472 pressing part,
472A Raised site,
472B Indentation site,
480 Movable type (die part),
486 irregularities,
E protrusion amount,
L indentation distance,
P circumferential direction,
S ₁ , S ₂ , S ₃ , S ₄ space,
W width,
Y Longitudinal direction.

Claims (24)

A method for producing an open cross-section part having a bent portion by press molding,
Having an open cross section, provided with a bent portion in a direction in which the open cross section extends,
The bent portion connects the curved inner wall portion, the outer wall portion spaced apart from the inner wall portion, and the end portion of the inner wall portion and the end portion of the outer wall portion. A preform having a wall, or
The bent portion is prepared to prepare a preformed body having a curved inner wall portion and a connecting wall portion extending from an end portion of the inner wall portion in a direction crossing the direction in which the open cross section extends. Process,
An arrangement step of arranging the preform in a mold;
In the middle of the mold clamping operation of the molding die, the inner wall portion is pushed by the molding die to generate a material flow, and at least a thickness of a part of the connection wall portion adjacent to the inner wall portion is set. The method further comprises a step of increasing the thickness in comparison with the plate thickness before the mold clamping operation. The preform formed in the preparation step has a protruding portion protruding from the outer surface side of the inner wall portion,
The method according to claim 1, wherein the material flow is generated by pressing the protrusion in the thickness increasing step.   3. The method according to claim 1, wherein the preformed body prepared in the preparation step is manufactured by press molding, and the inner wall portion is located in an extending flange portion. 4.   The method according to claim 3, wherein a direction in which the open section extends in the bent portion of the preform that is prepared in the preparing step is three-dimensionally bent. The open section of the preform formed in the preparation step is a hat shape or an L shape,
The connecting wall portion of the bent portion in the preform is flat with respect to a direction orthogonal to the direction in which the open cross section extends,
5. The method according to claim 4, wherein, in the thickening step, a pressing direction of the inner wall portion by the molding die is made to coincide with a direction orthogonal to a direction in which the open cross section extends. The connecting wall portion adjacent to the inner wall portion of the preform prepared in the preparation step has wrinkle generation suppressing means,
The method according to any one of claims 3 to 5, wherein generation of wrinkles in the connecting wall portion is suppressed in the thickening step.   The method according to claim 6, wherein the wrinkle generation suppressing unit includes an embossed portion formed in the connecting wall portion adjacent to the inner wall portion.   The embossed shape of the embossed part is a rectangular shape, and the ridgelines of the embossed shape facing each other are parallel to the pressing direction of the inner wall portion by the molding die. the method of.   The method according to any one of claims 2 to 8, wherein a plurality of the protrusions are arranged apart from each other in a direction in which the open cross section of the preform is extended. Having an open cross section, provided with a bent portion in a direction in which the open cross section extends,
The bent portion connects the curved inner wall portion, the outer wall portion spaced apart from the inner wall portion, and the end portion of the inner wall portion and the end portion of the outer wall portion. A press-formed product having a wall, or
The bent portion is a press-formed product having a curved inner wall portion, and a connecting wall portion extending from the end of the inner wall portion in a direction crossing the direction in which the open cross section extends,
The plate thickness of at least a part of the connecting wall portion adjacent to the inner wall portion is increased by press molding as compared to the plate thickness before the press molding, and
A press-formed product, wherein a thickness of a portion where the thickness is increased is larger than a thickness of a peripheral portion of the portion.   The press-formed product according to claim 10, wherein the hardness of the portion where the plate thickness is increased is greater than the hardness of the peripheral portion by work hardening by the press molding. It is manufactured from a preform that is manufactured by press molding,
The press-molded product according to claim 10 or 11, wherein the inner wall portion extends and is located at a flange portion.   The press-formed product according to claim 12, wherein a direction in which the open section extends in the bent portion is bent three-dimensionally.   The press-formed product according to claim 13 or 13, wherein the connecting wall portion has an embossed portion adjacent to the inner wall portion.   The embossed shape of the embossed portion is a rectangular shape, and the ridgelines of the embossed shape facing each other are parallel to the pressing direction of the inner wall portion by the molding die. Press-formed product. An apparatus for producing an open cross-section part having a bent portion by press molding,
Having an open cross section, provided with a bent portion in a direction in which the open cross section extends,
The bent portion connects the curved inner wall portion, the outer wall portion spaced apart from the inner wall portion, and the end portion of the inner wall portion and the end portion of the outer wall portion. A preform having a wall, or
The bent portion includes a preformed body having a curved inner wall portion and a connecting wall portion extending from an end portion of the inner wall portion in a direction intersecting with the extending direction of the open cross section. Having a mold to be clamped,
The mold is
A punch portion disposed inside the preform,
A die portion disposed outside the preform,
The die part is
A fixed mold that presses a part of the connecting wall portion in cooperation with the punch portion;
A portion of the connecting wall portion that is spaced apart and opposed to the fixed mold and is adjacent to the inner wall section is pressed in cooperation with the punch section, and by relative movement with the fixed mold, the A movable mold that presses the inner wall portion and clamps the mold,
The cross-sectional thickness of the cavity formed by the punch portion and the movable die at the time of mold clamping is set to be larger than the plate thickness of the preform, at least with respect to the plate thickness of a part of the connecting wall portion adjacent to the inner wall portion. Has been
The punch portion and the die portion are
During the mold clamping operation of the mold, the movable mold pushes the inner wall portion of the bent portion to generate a material flow, and at least a part of the connecting wall portion adjacent to the inner wall portion. The thickness of the plate is compared with the plate thickness before the mold clamping operation, and is increased.   The preform has a protruding portion that protrudes from the outer surface side of the inner wall portion of the bent portion, and the pressing surface for pressing the inner wall portion of the movable mold is protruded during the mold clamping operation. The apparatus according to claim 16, wherein the material flow is generated by pressing the part. The fixed mold has a comb-like concavo-convex portion disposed on an end surface facing the movable mold,
The apparatus according to claim 16 or 17, wherein the movable mold has a comb-shaped concavo-convex portion that is disposed on an end face opposite to the fixed die and can be fitted to the concavo-convex portion.   The apparatus according to any one of claims 16 to 18, wherein the preform is manufactured by press molding, and the inner wall portion extends and is positioned at a flange portion.   The apparatus according to claim 19, wherein a direction in which the open section extends in the bent portion is bent three-dimensionally. The open cross section is a hat shape or an L shape,
The connecting wall portion of the bent portion is flat with respect to a direction orthogonal to a direction in which the open cross section extends,
The pressing surface for pressing the inner wall portion of the movable mold corresponds to the bent portion, and is bent three-dimensionally, and the pressing direction of the movable mold is orthogonal to the direction in which the open cross section extends. The apparatus according to claim 20, wherein the apparatus corresponds to a direction in which the camera is operated. The punch portion is
A fixed die that presses a part of the connecting wall portion spaced apart from the inner wall portion in cooperation with the fixed die of the die portion;
A movable die that is spaced apart and opposed to the fixed die of the punch portion and supports a part of the connecting wall portion adjacent to the inner wall portion;
The relative movement of the movable mold of the die section and the relative movement of the movable mold of the punch section are linked to each other. Equipment. The fixed die of the punch portion has a comb-like uneven portion disposed on an end surface of the punch portion facing the movable die,
The apparatus according to claim 22, wherein the movable mold has a comb-shaped uneven portion that is disposed on an end surface facing the fixed die and is freely fitted to the uneven portion. The connecting wall portion has an embossed portion adjacent to the inner wall portion,
The embossed shape of the embossed part is a rectangular shape,
The apparatus according to any one of claims 19 to 23, wherein the movable mold pushes the inner wall portion in parallel to the ridge lines of the embossed shape facing each other.

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