JP-7856686-B2 - Press-formed product and method for manufacturing a press-formed product

Inventors

• 藤井 さくら

Assignees

• フタバ産業株式会社

Dates

Publication Date

20260511

Application Date

20240205

Claims (9)

1. Plate-shaped part and A plate-shaped wall portion extending from the plate-shaped portion in a direction intersecting the plate-shaped portion, A plate-shaped flange portion protruding from the tip of the aforementioned wall portion, It has, The wall portion has a flat, straight edge portion and at least one curved portion whose cross-sectional shape at the cut surface along the plate-like portion is an arc shape that bulges radially outward. The at least one curved surface portion has a first curved surface portion and a second curved surface portion that is closer to the flange portion than the first curved surface portion, and the first curved surface portion and the second curved surface portion are connected to the straight edge portion in the same plane as the straight edge portion. A press-formed product in which the radius of curvature at the cross-section of the second curved surface is smaller than the radius of curvature at the cross-section of the first curved surface.
2. The wall portion further has a stepped surface formed between the first curved portion and the second curved portion, The press-formed product according to claim 1, wherein the second curved portion is located radially outward from the first curved portion.
3. The wall portion has a plurality of stepped surfaces, as described in claim 2.
4. The aforementioned press-formed product is a body part for an automobile, as described in any one of claims 1 to 3.
5. The aforementioned press-formed product has a bag shape with a recess, The wall portion has a plurality of the at least one curved portion, The straight edge portion is configured to connect the plurality of curved portions, as described in any one of claims 1 to 3.
6. A method for manufacturing a press-formed product having a predetermined target shape, using a first mold and a second mold, The aforementioned press-formed product is Plate-shaped part and A plate-shaped wall portion extending from the plate-shaped portion in a direction intersecting the plate-shaped portion, A plate-shaped flange portion protruding from the tip of the aforementioned wall portion, It has, The wall portion has a flat, straight edge portion and at least one curved portion whose cross-sectional shape at the cut surface along the plate-like portion is an arc shape that bulges radially outward. The at least one curved surface portion has a first curved surface portion and a second curved surface portion that is closer to the flange portion than the first curved surface portion, and the first curved surface portion and the second curved surface portion are connected to the straight edge portion in the same plane as the straight edge portion. The radius of curvature at the cross-section of the second curved surface is configured to be smaller than the radius of curvature at the cross-section of the first curved surface. The first mold and the second mold are, respectively, A first molding section for forming the plate-like portion, A second molding section for forming the aforementioned wall portion, A third molding section for forming the at least one curved surface portion, It has, Placing a blank material between the separated first mold and the second mold, With the blank material positioned between the first mold and the second mold, the first mold and the second mold are brought close to each other, A method for manufacturing press-formed products including [specific components].
7. The wall portion further has a stepped surface formed between the first curved portion and the second curved portion, The method for manufacturing a press-formed product according to claim 6, wherein the second curved portion is located radially outward from the first curved portion.
8. The method for manufacturing a press-formed product according to claim 7, wherein the wall portion has a plurality of stepped surfaces.
9. The method for manufacturing a press-formed product according to any one of claims 6 to 8, wherein the press-formed product is a body part for an automobile.

Description

This disclosure relates to press-formed articles and methods for manufacturing press-formed articles. In press forming technology, Reference Document 1 discloses a technique for suppressing the occurrence of wrinkles in press-formed products. Patent No. 5569609 Figure 1 is a perspective view of a press-formed product in the first embodiment.Figure 2A is a plan view of the press-formed product shown in Figure 1. Figure 2B is a cross-sectional view taken along the line IIB-IIB in Figure 2A.Figure 3A is a plan view conceptually illustrating the difference in radius of curvature and perimeter at the corner of the press-formed product shown in Figure 1. Figure 3B is a cross-sectional view taken along the line IIIB-IIIB in Figure 3A.Figure 4 is a cross-sectional view of a press molding apparatus for manufacturing the press-formed product shown in Figure 1.Figure 5 is a perspective view of an intermediate formed by the press molding apparatus shown in Figure 4.Figure 6A is a plan view of a press-formed product according to the second embodiment. Figure 6B is a VIB-VIB cross-sectional view of Figure 6A.Figure 7 is a perspective view of a press-formed product according to the third embodiment. Hereinafter, exemplary embodiments of the present disclosure will be described with reference to the drawings. [1. First Embodiment] [1-1. Composition of press-formed products] <Overview of press-formed products> The first embodiment relates to a press-formed product and a method for manufacturing a press-formed product. Figure 1 shows a perspective view of a press-formed product 10 formed using the press-formed product manufacturing method according to the first embodiment. The press-formed product 10, after undergoing the drawing process according to the manufacturing method of this embodiment, is used as a component of an automobile body after undergoing necessary additional processes (e.g., trimming and bending processes). For example, the press-formed product 10 is used as a rear floor with a bag-like shape and a space for storing a spare tire. Furthermore, in the space of the press-formed product 10, for example in an electric vehicle (EV), tools, a safety vest, and a charging cable can also be stored in addition to the spare tire. The press-formed product 10 and its manufacturing method can be applied not only to rear floors but also to various other parts and products. The press-formed product 10 is obtained by press forming (including drawing and bending processes) of a blank material 50 made of steel sheet. The material of the blank material 50 used for the press-formed product 10 is, for example, a steel sheet coated with alloyed zinc plating. The blank material 50 can have a thickness of 0.6 mm to 1.4 mm. In this embodiment, the thickness of the blank material 50 is 0.6 mm. <Overall shape of the press-formed product> The press-formed product 10 has a deep bag shape. A bag shape is a shape that can enclose an object inside. This enclosing means holding the object with the bottom wall and side walls. In other words, a bag shape is a configuration that has a bottom wall and one or more side walls. The dimensions of the bag-shaped portion of the press-formed product 10 (the portion other than the flange portion 16 described later) are, for example, approximately 600 mm in width, 200 mm in depth, and 180 mm in height. Hereinafter, the direction along the depth of the press-formed product 10 (the vertical direction in Figure 1) will be referred to as the depth direction X. The depth of the press-formed product 10 is 80 mm or more. The press-forming method of drawing the blank material 50 into a deep bag shape is also called deep-drawing. The press-formed product 10 has a top plate portion 12, a vertical wall portion 14, and a flange portion 16. In Figure 1, for the sake of explanation, the top plate portion 12 is shown as the upper part of the press-formed product 10; however, the press-formed product 10 is used in an inverted orientation compared to the orientation shown in Figure 1. Therefore, the top plate portion 12 is sometimes referred to as the bottom wall portion, considering the usage state. In this embodiment, the space enclosed by the top plate portion 12 and the vertical wall portion 14 is a space for storing a spare tire, tools, a safety vest, a charging cable, etc. The top plate portion 12 is substantially flat. In a plan view, the top plate portion 12 is substantially rectangular in shape, with two adjacent corners rounded to form the top plate curved portions 18 described later. However, the shape of the top plate portion 12 may generally be other polygonal shapes in a plan view. The top plate portion 12 has two curved top plate curved portions 18 on its outer circumference. In this embodiment, the shape of the top plate curved portions 18 is an arc shape within a perfect circle. However, the shape of the top plate curved portions 18 may be an arc shape within an ellipse, a composite curve shape, etc. The