Vehicle body frame unit

Abstract

An embodiment of the present invention provides a vehicle body frame unit comprising: a roof side rail disposed on a side surface portion of a vehicle body to support a roof; a side sill disposed below the roof side rail and supporting the lower portion of the vehicle body; and a pillar unit disposed between the roof side rail and the side sill and including multiple pillars. Each of the roof side rail and the pillar includes: an inner member including a first flange which protrudes outward from one end portion thereof and has a first length; and an outer member including a second flange which protrudes outward from one end portion thereof, faces the first flange, and has a second length different from the first length. The inner member and the outer member are coupled in a state in which the first flange and the second flange are in contact with each other to form a closed cross-section. The closed cross-section extends along the extending direction of the pillar while maintaining a constant area.

Description

Body frame unit

[0001] The present invention relates to a vehicle body frame unit.

[0002] Generally, the side reinforcement structure of the vehicle body is formed by including a side rail reinforcement positioned on the upper part of the vehicle body, an A-pillar reinforcement positioned vertically in front of the front door of the vehicle body, a B-pillar reinforcement positioned vertically in the center to separate the front door and the rear door of the vehicle body, a C-pillar reinforcement positioned vertically behind the rear door, and a side sill outer positioned on the lower part of the vehicle body, thereby providing structural rigidity to the upper, lower, and side parts of the vehicle body.

[0003] At this time, side body reinforcements such as the A-pillar, B-pillar, and C-pillar are manufactured by producing inner and outer parts separately and combining them. However, there is an increasing need for pillar sections that allow for shape changes to accommodate various vehicle forms, are suitable for mass production, can lower manufacturing costs, and ensure structural rigidity.

[0004] (Prior Art Literature)

[0005] (Patent Document 1) Republic of Korea Published Patent No. 10-2024-0026694 (February 29, 2024)

[0006] The present invention was devised to solve the above-mentioned problems, and aims to provide a vehicle body frame unit including a pillar section that is easy to manufacture and assemble, making it advantageous for mass production, and simultaneously lowers manufacturing costs.

[0007] The problems of the present invention are not limited to those described above. A person skilled in the art to which the present invention pertains will have no difficulty understanding additional problems of the present invention from the overall contents of this specification.

[0008] To achieve the above objectives, a body frame unit according to one embodiment of the present invention comprises a roof side rail disposed on the side of the body and supporting a roof, a side sill disposed below the roof side rail and supporting the lower part of the body, and a pillar portion disposed between the roof side rail and the side sill and including a plurality of pillars, wherein the roof side rail and the pillars comprise an inner member disposed protruding outward from one end and including a first flange having a first length, and an outer member disposed protruding outward from one end and facing the first flange and including a second flange having a second length different from the first length, wherein the inner member and the outer member are joined in a state where the first flange and the second flange are in contact with each other to form a closed cross-section, and the closed cross-section may extend with the same area along the extension direction of the pillars.

[0009] In one embodiment of the present invention, the first flange and the second flange are provided in pairs, and the two first flanges are each positioned at both ends of the inner member, and the two second flanges are each positioned at both ends of the outer member, so that they can face the two first flanges in a one-to-one manner.

[0010] In one embodiment of the present invention, when the inner member and the outer member are combined, a first area in which the first flange and the second flange are arranged together so as to overlap, and a second area in which only one of the first flange and the second flange is arranged may be formed.

[0011] In one embodiment of the present invention, the first flange and the second flange may be joined in the first region in a first joining manner to form the closed cross-section.

[0012] In one embodiment of the present invention, a side outer can be coupled to the second region in a second coupling method.

[0013] In one embodiment of the present invention, the second region may have a longer length than the first region.

[0014] In one embodiment of the present invention, the length of the first region may be 2 to 7 mm, and the length of the second region may be 10 to 15 mm.

[0015] In one embodiment of the present invention, the loop side rail may have two first flanges provided on the inner member, one of the two first flanges protruding downward from the lower end of the inner member and the other of the two first flanges protruding upward from the upper end of the inner member, and two second flanges provided on the outer member, one of the two second flanges protruding downward from the lower end of the outer member and the other of the two second flanges protruding upward from the upper end of the outer member.

[0016] In one embodiment of the present invention, the inner member of the loop side rail may include a bent portion formed by bending the first flange that is positioned to protrude upward.

[0017] In one embodiment of the present invention, the pillar may have different heights at the upper end of the inner member and the upper end of the outer member.

[0018] In one embodiment of the present invention, the upper portion of the inner member protrudes higher than the upper portion of the outer member, and when the roof side rail and the pillar are combined, the upper portion of the inner member of the pillar is combined with the inner member of the roof side rail, while the upper portion of the outer member of the pillar may be spaced apart from the outer member of the roof side rail.

[0019] In one embodiment of the present invention, when connecting the inner member or the outer member of the pillar to the loop side rail and the side sill, a connecting portion may be further included.

[0020] In one embodiment of the present invention, the upper portion of the inner member protrudes higher than the upper portion of the outer member, and the connecting portion may be arranged to simultaneously cover at least one part of the outer member of the pillar and at least one part of the outer member of the loop side rail.

[0021] In one embodiment of the present invention, the upper portion of the connecting portion is coupled to the outer surface of the outer member of the pillar, and the lower portion of the connecting portion may be coupled to the outer surface of the outer member of the loop side rail.

[0022] In one embodiment of the present invention, a side flange is provided that protrudes outwardly from one side, and the side flange may be coupled to at least one of the second region of the loop side rail and the second region of the pillar.

[0023] In one embodiment of the present invention, the upper portion of the outer member protrudes higher than the upper portion of the inner member, and the connecting portion may be arranged to simultaneously cover at least one part of the inner member of the pillar and at least one part of the inner member of the loop side rail.

[0024] In one embodiment of the present invention, the upper portion of the connecting portion is coupled to the inner surface of the inner member of the pillar, and the lower portion of the connecting portion may be coupled to the inner surface of the inner member of the loop side rail.

[0025] In one embodiment of the present invention, the connecting portion includes a side flange protruding outwardly from one side, and the side flange may be coupled to at least one of the second region of the loop side rail and the second region of the pillar.

[0026] In one embodiment of the present invention, the side seal may include an upper flange that is formed by folding a plate at least twice to form an open cross-section and protruding upward from the upper end thereof.

[0027] In one embodiment of the present invention, the upper portion of the connecting portion is coupled to the pillar, and the lower portion of the connecting portion may be coupled to the side seal.

[0028] The vehicle body frame unit according to the embodiments of the present invention minimizes the number of welding layers when manufacturing the pillar portion and the roof side rail, and when combining additional parts such as side outers with the pillar portion, thereby preventing welding defects and strength reduction in the vehicle body frame unit, and consequently securing sufficient strength while reducing the weight of the vehicle body frame unit.

[0029] In addition, when manufacturing the vehicle body frame unit, changes in the shape of the pillar part can be easily implemented in response to various shapes of the vehicle body, and thereby, when mass-producing the vehicle body frame unit and the pillar part, the effects of increased productivity and cost reduction can be secured.

[0030] FIG. 1 is a side view illustrating a vehicle body frame unit according to one embodiment of the present invention as seen from one side.

[0031] FIG. 2 is a cross-sectional view showing the A-pillar and the site outer connected thereto, viewed from the direction II' of FIG. 1.

[0032] FIG. 3 is a cross-sectional view illustrating an A-pillar according to an embodiment of the present invention, viewed from the direction II' of FIG. 1.

[0033] Figure 4 is an enlarged view of area A of Figure 1.

[0034] Figure 5(a) illustrates the A-pillar as viewed from the direction II' of Figure 4, and Figure 5(b) illustrates the A-pillar as viewed from the direction II-II' of Figure 4.

[0035] FIG. 6 is a cross-sectional view illustrating a non-pillar according to an embodiment of the present invention, viewed from the direction III-III' of FIG. 1.

[0036] FIG. 7 is a cross-sectional view illustrating a C-pillar according to an embodiment of the present invention as viewed from the direction IV-IV' of FIG. 1.

[0037] FIG. 8 is a cross-sectional view illustrating a D-pillar according to an embodiment of the present invention as viewed from the VV' direction of FIG. 1.

[0038] FIG. 9 is a side view illustrating a loop side rail according to one embodiment of the present invention.

[0039] Figure 10 (a) is a cross-sectional view taken in the direction of C1-C1' of Figure 9, and Figure 10 (b) is a cross-sectional view taken in the direction of C2-C2' of Figure 9.

[0040] FIG. 11 is a perspective view illustrating a side seal according to one embodiment of the present invention and a cross-sectional view illustrating an enlarged portion of the side seal.

[0041] FIG. 12 is a side view illustrating the vehicle body frame unit of FIG. 1 as viewed from the other side.

[0042] FIG. 13 schematically illustrates the side view of region A' of FIG. 1.

[0043] FIG. 14 schematically illustrates the side view of region A'' of FIG. 1.

[0044] Preferred embodiments of the present invention will be described below with reference to the attached drawings. However, embodiments of the present invention may be modified in various other forms, and the scope of the present invention is not limited to the embodiments described below.

[0045] In addition, embodiments of the present invention are provided to more fully explain the present invention to those with average knowledge in the relevant technical field.

[0046] In drawings, the shapes and sizes of elements may be exaggerated for clearer explanation.

[0047] In describing the embodiments of the present invention, if it is determined that a detailed description of known technology related to the present invention may unnecessarily obscure the essence of the present invention, such detailed description will be omitted. Furthermore, the terms described below are defined considering their functions in the present invention, and these may vary depending on the intentions or conventions of the user or operator. Therefore, such definitions should be based on the content throughout this specification. The terms used in the detailed description are merely for describing the embodiments of the present invention and should not be limited in any way. Unless explicitly stated otherwise, expressions in the singular form include the meaning of the plural form.

[0048] In this description, expressions such as “include” or “equipped” are intended to refer to certain characteristics, numbers, steps, actions, elements, parts or combinations thereof, and should not be interpreted to exclude the existence or possibility of one or more other characteristics, numbers, steps, actions, elements, parts or combinations thereof other than those described.

[0049] Unless otherwise specifically defined in the specification of the present invention, % units mean weight %.

[0050] In this specification, terms such as 'top', 'upper', 'upper surface', 'lower', 'lower surface', 'lower surface', and 'side surface' are based on the drawings and may actually vary depending on the direction in which the elements or components are arranged.

[0051] Additionally, throughout the specification, when it is said that one part is 'connected' to another part, this includes not only cases where they are 'directly connected,' but also cases where they are 'indirectly connected' with other elements in between.

[0052] The present invention will be described in detail below through each embodiment or example of the invention. It should be noted that each embodiment or example described in this specification is not limited to a single embodiment or example, but may also be combined with other embodiments or examples. Accordingly, the citation of claims in the patent claims is merely an example of an embodiment, and the technical concept of the present invention should not be interpreted as being limited only to a combination with the cited claims; rather, combinations with various claims are also included within the scope of the technical concept of the present invention.

[0053] FIG. 1 is a side view illustrating a vehicle body frame unit according to one embodiment of the present invention as seen from one side.

[0054] Referring to FIG. 1, the body frame unit (10) is a skeletal body that supports the side of a vehicle (not shown) and can be formed by connecting a plurality of frames. At this time, the body frame unit (10) may include a roof side rail (RS), a side sill (SS), and a pillar portion (PL).

[0055] The roof side rail (RS) supports the side of the vehicle's roof and can serve to maintain the upper rigidity of the vehicle body.

[0056] The roof side rail (RS) may include a front side rail (SR1), a first rear side rail (SR2), and a second rear side rail (SR3). At this time, based on the front-rear direction of the vehicle (e.g., the X-axis direction of the drawing), the front side rail (SR1) supports the front portions of both sides of the vehicle's roof (not shown), and the first rear side rail (SR2) and the second rear side rail (SR3) support the rear portions of both sides of the roof.

[0057] In this case, the loop side rail (RS) may be a structure in which the front side rail (SR1), the first rear side rail (SR2), and the second rear side rail (SR3) are continuously extended along the aforementioned front-rear direction (X). At this time, the loop side rail (RS) may be a single structure formed by combining the front side rail (SR1), the first rear side rail (SR2), and the second rear side rail (SR3).

[0058] The side sill (SS) is installed at the lower part of the vehicle body or vehicle body frame unit (10) to extend along the front-rear direction of the vehicle (e.g., X-axis direction) and can perform the role of maintaining the lower rigidity of the vehicle body.

[0059] The pillar section (PL) is positioned between the roof side rail (RS) and the side sill (SS) to support the roof. At this time, the pillar section (PL) may include a plurality of pillars.

[0060] In one embodiment, the pillar portion (PL) may include a vehicle A-pillar (hereinafter A-pillar) (100), a vehicle B-pillar (hereinafter B-pillar) (200), and a vehicle C-pillar (hereinafter C-pillar) (300). Additionally, the pillar portion (PL) may further include a vehicle D-pillar (hereinafter D-pillar) (400).

[0061] FIG. 2 is a cross-sectional view illustrating an A-pillar and a site outer connected thereto, viewed from the direction II' of FIG. 1. FIG. 3 is a cross-sectional view illustrating an A-pillar according to an embodiment of the present invention, viewed from the direction II' of FIG. 1.

[0062] Referring to FIGS. 2 and 3, the A-pillar (100) can be positioned at the front of the vehicle body frame unit (10) to support the roof. Here, "front" may refer to the front part of the vehicle where the vehicle body frame unit (10) is installed.

[0063] The A-pillar (100) may be a skeletal body extending from the rear position of the dash wheel arch (not shown) where the front tire is located in the vehicle to the front windshield (not shown) and the front door panel (not shown). Such an A-pillar (100) may have a structure in which an inner member (hereinafter, first inner member) (110) and an outer member (hereinafter, first outer member) (120) are joined together to form a closed cross-section.

[0064] The first inner member (110) may include a first body (111) and a first flange (112, 113). The first flange (112, 113) may be a part that comes into contact with and is joined to the second flange (122, 123) to be described later when the first inner member (110) is joined to the first outer member (120).

[0065] For example, two first flanges (112, 113) may be provided. Of the two first flanges (112, 113), one (hereinafter referred to as the first-1 flange) (112) may be positioned to protrude in a first outward direction (e.g., -X) from one end of the first body (111). And, of the two first flanges (112, 113), the other (hereinafter referred to as the first-2 flange) (113) may be positioned to protrude in a second outward direction (e.g., +X) from the other end of the first body (111).

[0066] In this case, the first body (111) can have various shapes. That is, the first body (111) can be provided in any shape as long as it includes a first flange (112, 113) at each end.

[0067] For example, the drawing illustrates an embodiment in which the first body (111) is curved to protrude inward (e.g., -Y) and has a '_' shape [hereinafter referred to as a hat shape], with first flanges (112, 113) provided at each end, but is not limited thereto. However, for convenience of explanation, the description will focus on the case where the first body (111) is in a hat shape.

[0068] In this specification, the inner direction refers to the direction in which the A-pillar (100) or the body frame unit (10) faces the interior of the vehicle when installed on the vehicle, and may mean the “-Y-axis direction” in the drawing. This is based on the case where the body frame unit (10) is installed on the right side when viewed from the front of the vehicle. Although not shown in the drawing, if the body frame unit (10) is installed on the left side of the vehicle, the inner direction may be the “+Y-axis direction.” For convenience of explanation, the following description will focus on the case where the inner direction is the “-Y-axis direction” and the outer direction is the “+Y-axis direction.”

[0069] The first outer member (120) may include a second body (121) and a second flange (122, 123). The second flange (122, 123) may be a part that comes into contact with and is joined to the first flange (112, 113) described above when the first outer member (120) is joined to the first inner member (110).

[0070] For example, two second flanges (122, 123) may be provided. Of the two, one of the second flanges (122, 123) (hereinafter referred to as the second-1 flange) (122) may be positioned to protrude in the first outer direction (-X) as described above from one end of the second body (121). And, of the two second flanges (122, 123), the other one (hereinafter referred to as the second-2 flange) (123) may be positioned to protrude in the second outer direction (+X) as described above from the other end of the second body (121).

[0071] In this case, the second body (121) can have various shapes. That is, the second body (121) can be provided in any shape as long as it includes a second flange (122, 123) at each end.

[0072] For example, as illustrated in the drawing, only an embodiment is shown in which the second body (121) is curved to protrude outwardly (+Y) and has a '_' shape (i.e., a hat shape), with second flanges (122, 123) provided at both ends of the second body (121), but the present invention is not limited thereto. However, for convenience of explanation, the explanation will focus on the case where the second body (121) is in a hat shape. Meanwhile, as previously stated, the outward direction (+Y) refers to the direction facing outward from the vehicle when the A-pillar (100) or the vehicle body frame unit (10) is installed on the vehicle.

[0073] The first inner member (110) and the first outer member (120) of the above form can be manufactured by bending the steel plate multiple times using a roll-forming method.

[0074] When the first inner member (110) and the first outer member (120) are joined, as described above, the first flange (112, 113) and the second flange (122, 123) can be joined in a state of contact. More specifically, the first-1 flange (112) and the second-1 flange (122) can be joined through a 'first joining method' with their opposing surfaces in contact with each other. Also, the first-2 flange (113) and the second-2 flange (123) can be joined through a 'first joining method' with their opposing surfaces in contact with each other. The first joining method may be, for example, a laser welding method.

[0075] The length of the first flange (112, 113) (hereinafter, the first length) may differ from the length of the second flange (122, 123) (hereinafter, the second length). Due to this difference in length, when the first flange (112, 113) and the second flange (122, 123) come into contact with each other and are joined, a first region (A11) and a second region (A21) may be formed.

[0076] The first area (A11) may be an area where the first flange (112, 113) and the second flange (122, 123) are in contact with each other and overlap. The second area (A21) may be an area where only one of the first flange (112, 113) and the second flange (122, 123) is placed. The second area (A21) may be an area in which one end is connected to the first area (A11) and the other end extends outwardly from the first area (A11). In this case, only one of the first-1 flange (112), the first-2 flange (113), the second-1 flange (122), and the second-2 flange (123) may be placed in the second area (A21).

[0077] A first region (A11) may be formed between the first-1 flange (112) and the second-1 flange (122), and between the first-2 flange (113) and the second-2 flange (123), respectively. At this time, two second regions (A21) may also be formed. One of the two second regions (A21) may be a region extending in a first outer direction (-X) from the first region (A11) formed between the first-1 flange (112) and the second-1 flange (122). And the other of the two second regions (A21) may be a region extending in a second outer direction (+X) from the first region (A11) formed between the first-2 flange (113) and the second-2 flange (123).

[0078] In the above case, a 'first weld (Wb11)' may be formed in each of the first area (A11) where the first-1 flange (112) and the second-1 flange (122) come into contact and overlap, and the first area (A11) where the first-2 flange (113) and the second-2 flange (123) come into contact and overlap. In this way, the first outer member (120) and the first inner member (110) are provided in a hat shape curved in opposite directions, and the first outer member (120) and the first inner member (110) are joined to the first flange (112, 113) and the second flange (122, 123) through a first joining method, thereby forming an A-pillar (100) having a closed cross-section. Accordingly, an empty space (E) can be placed inside the A-pillar (100).

[0079] Meanwhile, the first region (A11) and the second region (A21) described above may have different lengths. Hereinafter, for convenience of explanation, the length of the first region (A11) will be referred to as the 'length of the first region (L11)' and the length of the second region (A21) will be referred to as the 'length of the second region (L21)'.

[0080] More specifically, the second region (A21) may have a longer length than the second region (A21). That is, the length of the second region (L21) may be longer than the length of the first region (L11). The length of the second region (L21) may be at least twice the length of the first region (L11). For example, the length of the first region (L11) may be 2 to 7 mm, and the length of the second region (L21) may be 10 to 15 mm. Preferably, the length of the first region (L11) may be at least 5 mm, and the length of the second region (L21) may be at least 13 mm, but is not limited thereto.

[0081] As illustrated exemplarily in FIG. 2, a side outer (SO) may be assembled to the A-pillar (100). The side outer (SO) is a part that covers the outer surface of the body frame unit (10) and may include a front quarter positioned at the front of the body and a rear quarter positioned at the rear of the body.

[0082] The side outer (SO) can be connected to the second region (A21) of the A-pillar (100). At this time, the side outer (SO) can be connected to the second region (A21) through a second connection method. More specifically, one end of the side outer (SO) can be connected to either of the two second regions (A21) formed in the A-pillar (100) by the 'second connection method'. And, the other end of the side outer (SO) can be connected to the other of the two second regions (A21) formed in the A-pillar (100) by the 'second connection method'. By being connected in this way, the side outer (SO) can cover the outer side of the A-pillar (100). Here, the outer side refers to the outer direction (+Y) of the vehicle, and when the side outer (SO) is connected to the A-pillar (100), the A-pillar (100) may not be visible to the naked eye from the outside of the vehicle.

[0083] In one embodiment, the second joining method may be different from the first joining method. For example, while the first joining method is a laser welding method as described above, the second joining method may be a spot welding method.

[0084] In this case, the first region (A11) has a relatively narrow area due to the relatively short length (L1) of the first region, and the first inner member (110) and the first outer member (120) can be joined by applying concentrated heat to this first region (A11) through the first joining method, the 'laser welding method'.

[0085] Furthermore, the second region (A21) has a relatively wide length (L2) due to the relatively long second region length, and by applying heat to this second region (A21) through a second joining method, a 'spot welding method,' the first inner member (110) and the side outer (SO) can be joined. At this time, one end of the side outer (SO) can be joined to the second region (A21) of the first-1 flange (112) by a spot welding method to form a 'second weld (Wb2).' Then, the other end of the side outer (SO) can be joined to the second region (A21) of the first-2 flange (113) by a spot welding method to form a 'second weld (Wb2).'

[0086] In this way, the first inner / outer members (110, 120) constituting the A-pillar (100) are joined in the first area (A11), and separately, the side outer (SO) can be joined to the second area (A21) where only one of the first and second flanges (111, 112, 121, 122) is positioned. Accordingly, the joining portion of the side outer (SO) can be formed by a double weld in which only one flange and the side outer (SO) are welded in an overlapping state. Additionally, when additional parts other than the side outer (SO) are assembled to the A-pillar (100), the additional parts can be joined to the second area (A21) which has a relatively large area. At this time, the additional parts can be joined to the second area (A21) where the side outer (SO) is joined and the double weld is formed.

[0087] In this way, even when additional parts are added to the A-pillar (100), only three-layer welding is formed at the part where the additional parts are added, thereby preventing four-layer welding from being formed on the A-pillar (100). This ensures high strength of the joined part and prevents the weight of the vehicle body frame unit (10) from increasing excessively due to four or more layers of overlapping welding.

[0088] Meanwhile, the present invention is not limited to the aforementioned embodiments, and as another embodiment, the A-pillar (100) may have a second flange (122, 123) that is longer than the first flange (112, 113). As yet another embodiment, the first-1 flange (112) and the first-2 flange (113) may have different lengths, or the second-1 flange (122) and the second-2 flange (123) may have different lengths.

[0089] Figure 4 is an enlarged view of area A of Figure 1. Also, Figure 6 (a) shows the A-pillar viewed from the direction II' of Figure 4, and Figure 6 (b) shows the A-pillar viewed from the direction II-II' of Figure 4.

[0090] Referring to FIGS. 1 to 5, the A-pillar (100) may be in the form of at least two unit structures combined that extend in different directions.

[0091] For example, the A-pillar (100) may be in the form of a combination of a first unit structure (100) extending in a 'first extension direction (B1)' parallel to the vertical direction (Z) as shown in FIG. 1, and a second unit structure (100-2) extending in a 'second extension direction (B2)' inclined downward toward the rear from the bottom of the first unit structure (100).

[0092] In this case, the unit structures (100, 100-2) forming the A-pillar (100) may have a structure in which the first inner member (110) and the first outer member (120) are mutually coupled to form a closed cross-section, as described above. At this time, the unit structures (100, 100-2) may have the same closed cross-section. Here, having the same closed cross-section may mean that the shape and area of ​​the closed cross-section formed inside, surrounded by the first inner member (110) and the second outer member (120), are the same.

[0093] More specifically, the first unit structure (100) may be extended along the first extension direction (B1). In this case, the first unit structure (100) may be extended along the first extension direction (B1) to have a uniformly closed cross-section throughout. Similarly, the second unit structure (100-2) may be extended along the second extension direction (B2). In this case, the second unit structure (100-2) may be extended along the second extension direction (B2) to have a uniformly closed cross-section throughout.

[0094] Additionally, the unit structures (100, 100-2) may have the same closed cross-section. Accordingly, when the first unit structure (100) and the second unit structure (100-2) are combined, the closed cross-section may also be the same at the part where the unit structures (100, 100-2) are connected (hereinafter, unit structure connection part). The unit structure connection part is a part where the extension direction of the A-pillar (100) changes, and it may be a part where the lower part of the first unit structure (100) and the upper part of the second unit structure (100-2) are cut along the same cutting direction (C) and then joined. At this time, as the unit structures (100, 100-2) have the same closed cross-section, when manufacturing the A-pillar (100), the closed cross-section formed in the first unit structure (100) and the closed cross-section formed in the second unit structure (100-2) at the unit structure connection part can be connected to each other and become continuous.

[0095] An A-pillar (100) having the shape described above can be manufactured using a long structure having the same closed cross-section manufactured through a roll forming process. That is, the A-pillar (100) can be manufactured by cutting a single long structure that extends to have the same closed cross-section overall to form a plurality of unit structures (100, 100-2) and then rejoining them through a method such as welding.

[0096] Meanwhile, although the A-pillar (100) has been described with an embodiment in which two unit structures (100, 100-2) are connected, the present invention is not limited thereto. That is, the number of unit structures constituting the A-pillar (100) can be increased or decreased, and the connection form of the unit structures can also be freely changed as needed.

[0097] FIG. 6 is a cross-sectional view illustrating a non-pillar according to an embodiment of the present invention, viewed from the direction III-III' of FIG. 1.

[0098] Referring to FIG. 6, the B-pillar (200) can be positioned in the center of the vehicle body frame unit (10) to support the roof of the vehicle. That is, the B-pillar (200) can be positioned between the A-pillar (100) and the C-pillar (300) to be described later to support the roof.

[0099] The non-pillar (200) may have a structure in which an inner member (hereinafter, second inner member) (210) and an outer member (hereinafter, second outer member) (220) are mutually joined to form a closed cross-section. At this time, the second inner member (210) may include a first body (211) and a first flange (212, 213).

[0100] Two first flanges (212, 213) may be provided. One of the two first flanges (212, 213) (hereinafter referred to as the first-1 flange) (212) may be positioned to protrude in a first outward direction (-X) from one end of the first body (211). And the other of the two first flanges (212, 213) (hereinafter referred to as the first-2 flange) (213) may be positioned to protrude in a second outward direction (+X) from the other end of the first body (211).

[0101] In this case, the first body (211) may be provided in any shape as long as it includes a first flange (212, 213) at each end. For example, as shown in the drawing, the first body (211) may be provided in a curved hat shape protruding in the aforementioned inner direction (-Y) with the first flanges (212, 213) provided at each end, but is not limited thereto.

[0102] The second outer member (220) may include a second body (221) and a second flange (222, 223).

[0103] For example, two second flanges (222, 223) may be provided. One of the two second flanges (222, 223) (hereinafter referred to as the second-1 flange) (222) may be positioned to protrude in the first outer direction (-X) as described above from one end of the second body (221). And, the other of the two second flanges (222, 223) (hereinafter referred to as the second-2 flange) (223) may be positioned to protrude in the second outer direction (+X) as described above from the other end of the second body (221).

[0104] In this case, the second body (221) can be provided in any shape as long as it includes a first flange (212, 213) at each end, just like the first body (211). For example, as shown in the drawing, the second body (221) can be provided in a curved hat shape protruding outward in the aforementioned direction (+Y), with a second flange (222, 223) provided at each end, but is not limited thereto.

[0105] The second inner member (210) and the second outer member (220) of the above form can be manufactured by bending a steel plate multiple times using a roll forming method, which is identical or similar to the A-pillar (100) described above. At this time, since the specific method of manufacturing the B-pillar (200) using a roll forming method is similar to the manufacturing method of the A-pillar (100) described above, a detailed explanation thereof will be omitted.

[0106] When the second inner member (210) and the second outer member (220) are combined, the first flange (212, 213) and the second flange (222, 223) can be combined in a state where they are in contact with each other. More specifically, the first-1 flange (212) and the second-1 flange (222) can be combined through the 'first combination method' described above in a state where their opposing surfaces are in contact with each other. Also, the first-2 flange (213) and the second-2 flange (223) can be combined through the 'first combination method' described above in a state where their opposing surfaces are in contact with each other.

[0107] At this time, the first flange (212, 213) and the second flange (222, 223) may be formed with different lengths. Accordingly, when the second inner member (210) and the second outer member (220) are combined, a ‘first area (A12)’ which is an area where the first flange (212, 213) and the second flange (222, 223) come into contact with each other and overlap, and a ‘second area (A22)’ which is an area where only one of the first flange (212, 213) and the second flange (222, 223) is positioned may be formed. In this case, a 'first weld (Wb12)' may be formed in each of the first area (A12) where the first-1 flange (212) and the second-1 flange (222) come into contact and overlap, and the first area (A12) where the first-2 flange (213) and the second-2 flange (223) come into contact and overlap. Additionally, an empty space (E) may be formed inside the non-pillar (200), which is in the form of a combined second outer member (220) and a second inner member (210).

[0108] The 'first region length (L12)', which is the length of the first region (A12), and the 'second region length (L22)', which is the length of the second region (A22), may be different from each other. More specifically, the second region length (L22) may be longer than the first region length (L12). The second region length (L22) may be at least twice the length of the first region (L12). For example, the first region length (L12) may be 2 to 7 mm, and the second region length (L22) may be 10 to 15 mm. Preferably, the first region length (L12) may be at least 5 mm, and the second region length (L22) may be at least 13 mm, but is not limited thereto.

[0109] Additionally, although not shown in the drawing, other parts such as a side outer (SO) may be attached to the B-pillar (200), similar to the A-pillar (100). In this case, the side outer (SO) may be attached to the second region (A22) of the B-pillar (200) using the 'second attachment method' described above. By being attached in this way, the side outer (SO) can cover the outer side of the B-pillar (200).

[0110] In this case, the second inner member (210) and the second outer member (220) constituting the non-pillar (200) are joined together in the first area (A12), and additional parts such as the side outer (SO) can be joined separately in the second area (A22). Accordingly, the joining portion of the side outer (SO) forms a double-layer weld in which only one flange and the side outer (SO) overlap and are welded, and a triple-layer weld can be formed even when additional parts are assembled therein. That is, it is possible to prevent the formation of a four-layer weld on the non-pillar (200), thereby ensuring high strength while simultaneously preventing an excessive increase in weight, which is the same or similar to the aforementioned A-pillar (100).

[0111] The non-pillar (200) described above may be extended along one direction. For example, the direction of extension of the non-pillar (200) may be the height direction of the vehicle or the vertical direction (Z). In this case, the non-pillar (200) may be extended in a straight line along the vertical direction (Z) between the roof side rail (RS) and the side sill (SS). At this time, the non-pillar (200) may be extended to have the same closed cross-section along its direction of extension [i.e., the vertical direction (Z)]. By doing so, the non-pillar (200) may have a shape that has the same closed cross-section along its entire length.

[0112] FIG. 7 is a cross-sectional view illustrating a C-pillar according to an embodiment of the present invention as viewed from the direction IV-IV' of FIG. 1.

[0113] Referring to FIG. 7, the C-pillar (300) can be positioned at the rear of the vehicle body frame unit (10). More specifically, the C-pillar (300) is positioned at the rear of the vehicle body frame unit (10), but is positioned between the B-pillar (200) and the D-pillar (400) to be described later, so as to support the roof of the vehicle. Here, "rear" may refer to the rear part of the vehicle where the vehicle body frame unit (10) is installed.

[0114] The C-pillar (300) may have a structure in which an inner member (hereinafter, third inner member) (310) and an outer member (hereinafter, third outer member) (320) are joined together to form a closed cross-section. At this time, the third inner member (310) may include a first body (311) and a first flange (312, 313).

[0115] The first body (311) can have various shapes. That is, the first body (311) can be provided in any shape as long as it includes one first flange (312, 313) at each end.

[0116] For example, the first body (311) may be extended in a straight line along one direction [e.g., the front-rear direction (X)]. In this case, first flanges (312, 313) may be provided at each end of the first body (311). One of these two first flanges (312, 313) (hereinafter referred to as the first-1 flange) (312) may be positioned to protrude in the first outer direction (-X) from one end of the first body (311). And the other of the two first flanges (312, 313) (hereinafter referred to as the first-2 flange) (313) may be positioned to protrude in the second outer direction (+X) from the other end of the first body (311).

[0117] Accordingly, the third inner member (310) may be provided in the form of a single flat plate extending in a straight line along the front-rear direction (X). Although the present invention is not limited thereto, for the convenience of explanation, the description will focus on the case where the first body (311) and the third inner member (310) including it are in the form of a straight plate.

[0118] The third outer member (320) may include a second body (321) and a second flange (322, 323). For example, two second flanges (322, 323) may be provided. One of the two second flanges (322, 323) (hereinafter referred to as the second-1 flange) (322) may be arranged to protrude in the first outer direction (-X) as described above from one end of the second body (321). And the other of the two second flanges (322, 323) (hereinafter referred to as the second-2 flange) (323) may be arranged to protrude in the second outer direction (+X) as described above from the other end of the second body (321).

[0119] The second body (321), like the first body (311), can be provided in any shape as long as it includes a second flange (322, 323) at each end. For example, the second body (321) may be curved so as to protrude outward (+Y) of the vehicle described above, with a second flange (322, 323) provided at each end. In this case, the third outer member (320) may have a 'hat shape,' but as previously stated, the shape of the third outer member (320) is not limited thereto.

[0120] The third outer member (320) of the above form can be manufactured by bending a steel plate multiple times using a roll forming method, similar to the A-pillar (100) or B-pillar (200) described above. At this time, since the specific method of manufacturing the C-pillar (300) using a roll forming method is similar to the manufacturing method of the A-pillar (100) described above, a detailed explanation thereof will be omitted.

[0121] In addition, the inner member (320) and the outer member (330) as described above can be joined together to form a closed cross-section to form a C-pillar (300). Accordingly, the C-pillar (300) can have a flat shape that protrudes outward in a hat shape (+Y) but does not protrude inward in the vehicle's direction (-Y).

[0122] In the above case, when the third inner member (310) and the third outer member (320) are combined, the first flange (312, 313) and the second flange (322, 323) can be combined in a state where they are in contact with each other. More specifically, the first-1 flange (312) and the second-1 flange (322) can be combined through the 'first combination method' described above in a state where their facing surfaces are in contact with each other. Also, the first-2 flange (313) and the second-2 flange (323) can be combined through the 'first combination method' described above in a state where their facing surfaces are in contact with each other.

[0123] At this time, the first flange (312, 313) and the second flange (322, 323) may be formed with different lengths. Accordingly, when the third inner member (310) and the third outer member (320) are combined, a ‘first area (A13)’ in which the first flange (312, 313) and the second flange (322, 323) come into contact with each other and overlap, and a ‘second area (A23)’ in which only one of the first flange (312, 313) and the second flange (322, 323) is positioned may be formed. In this case, a ‘first weld (Wb13)’ may be formed in each of the ‘first area (A13)’ where the first-1 flange (312) and the second-1 flange (322) come into contact and overlap, and the ‘first area (A13)’ where the first-2 flange (313) and the second-2 flange (323) come into contact and overlap. Additionally, an empty space (E) may be formed inside the C-pillar (300), which is in the form of a combined third outer member (320) and a third inner member (310).

[0124] The 'first region length (L13)', which is the length of the first region (A13), and the 'second region length (L23)', which is the length of the second region (A23), may be different from each other. More specifically, the second region length (L23) may be longer than the first region length (L13). The second region length (L23) may be at least twice the length of the first region (L13). For example, the first region length (L13) may be 2 to 7 mm, and the second region length (L23) may be 10 to 15 mm. Preferably, the first region length (L13) may be at least 5 mm, and the second region length (L23) may be at least 13 mm, but is not limited thereto.

[0125] Additionally, although not shown in the drawing, other parts such as a side outer (SO) may be attached to the C-pillar (300). In this case, the side outer (SO) may be attached to the second region (A23) of the C-pillar (300) using the 'second attachment method' described above. In this case, by being attached in this manner, the side outer (SO) can cover the outer side of the C-pillar (300), which is the same or similar to the A-pillar (100) and B-pillar (200) described above.

[0126] In this case, the third inner member (310) and the third outer member (320) constituting the C-pillar (300) are joined together in the first area (A13), and additional parts such as the side outer (SO) can be joined separately in the second area (A23). Accordingly, the joining portion of the side outer (SO) forms a double weld in which only one flange and the side outer (SO) overlap and are welded, and even if additional parts are assembled therein, only a triple weld can be formed. That is, it is possible to prevent the formation of a four-layer weld on the C-pillar (300), and, as with the A-pillar (100) and B-pillar (200) described above, high strength can be secured while preventing an excessive increase in weight.

[0127] The C-pillar (300) described above may be extended along one direction. For example, the direction of extension of the C-pillar (300) may be the height direction of the vehicle or the vertical direction (Z). In this case, the C-pillar (300) may be extended in a straight line along the vertical direction (Z) between the first rear side rail (SR2) or the second rear side rail (SR3) and the side sill (SS). At this time, the C-pillar (300) may be extended to have the same closed cross-section along its direction of extension [i.e., the vertical direction (Z)]. By doing so, the C-pillar (300) may have a shape having the same closed cross-section over its entire length.

[0128] FIG. 8 is a cross-sectional view illustrating a D-pillar according to an embodiment of the present invention as viewed from the VV' direction of FIG. 1.

[0129] Referring to FIG. 8, the D-pillar (400) is positioned further rearward than the aforementioned C-pillar (300) of the body frame unit (10) to support the roof of the vehicle. The D-pillar (400) may be a skeletal body extending from the front position of the dash wheel arch (not shown) where the rear tire is located in the vehicle to between the rear windshield (not shown) and the rear door panel (not shown).

[0130] The D-pillar (400) may have a structure in which an inner member (hereinafter, fourth inner member) (410) and an outer member (hereinafter, fourth outer member) (420) are mutually joined to form a closed cross-section. At this time, the fourth inner member (410) may include a first body (411) and a first flange (412, 413).

[0131] The first body (311) can have various shapes. That is, the first body (311) can be provided in any shape as long as it includes one first flange (312, 313) at each end.

[0132] For example, the first body (411) may be extended in a straight line along one direction [e.g., the front-rear direction (X)]. In this case, first flanges (412, 413) may be provided at each end of the first body (411). One of these two first flanges (412, 413) (hereinafter referred to as the first-1 flange) (412) may be positioned to protrude in the first outer direction (-X) from one end of the first body (411). And the other of the two first flanges (412, 413) (hereinafter referred to as the first-2 flange) (413) may be positioned to protrude in the second outer direction (+X) from the other end of the first body (311).

[0133] Accordingly, the fourth inner member (410) may be provided in the form of a single flat plate extending in a straight line along the front-rear direction (X). Although the present invention is not limited thereto, for the convenience of explanation, the description will focus on the case where the first body (411) and the fourth inner member (410) including it are in the form of a straight plate.

[0134] The second body (421), like the first body (411), can be provided in any shape as long as it includes a second flange (422, 423) at each end. For example, the second body (421) may be curved so as to protrude outward (+Y) of the vehicle described above, with a second flange (422, 423) provided at each end. In this case, the fourth outer member (420) may have a 'hat shape,' but as previously stated, the shape of the fourth outer member (340) is not limited to this.

[0135] The fourth outer member (420) of the above form can be manufactured by bending a steel plate multiple times using a roll forming method, as described above or similarly. At this time, since the specific method of manufacturing the D-pillar (400) using the roll forming method is similar to the manufacturing method of the A-pillar (100) described above, a detailed explanation thereof will be omitted.

[0136] In addition, the inner member (420) and the outer member (430) as described above can be joined together to form a closed cross-section to form a D-pillar (400). Accordingly, the D-pillar (400) can have a flat shape that protrudes in a hat shape in the outer direction (+Y) but does not protrude in the inner direction (-Y).

[0137] In the above case, when the fourth inner member (410) and the fourth outer member (420) are combined, the first flange (412, 413) and the second flange (422, 423) can be combined in a state where they are in contact with each other. More specifically, the first-1 flange (412) and the second-1 flange (422) can be combined through the 'first combination method' described above in a state where their facing surfaces are in contact with each other. Also, the first-2 flange (413) and the second-2 flange (423) can be combined through the 'first combination method' described above in a state where their facing surfaces are in contact with each other.

[0138] At this time, the first flange (412, 413) and the second flange (422, 423) may have different lengths. Accordingly, when the fourth inner member (410) and the fourth outer member (420) are combined, a ‘first area (A14)’ in which the first flange (412, 413) and the second flange (422, 423) come into contact with each other and overlap, and a ‘second area (A24)’ in which only one of the first flange (412, 314) and the second flange (422, 423) is positioned may be formed. In this case, a ‘first weld (Wb14)’ may be formed in each of the ‘first area (A14)’ where the first-1 flange (412) and the second-1 flange (422) come into contact and overlap, and the ‘first area (A14)’ where the first-2 flange (413) and the second-2 flange (423) come into contact and overlap. Additionally, an empty space (E) may be formed inside the D-pillar (400), which is in the form of a combined fourth outer member (420) and a fourth inner member (410).

[0139] The 'first region length (L14)', which is the length of the first region (A14), and the 'second region length (L24)', which is the length of the second region (A24), may be different from each other. More specifically, the second region length (L24) may be longer than the first region length (L14). The second region length (L24) may be at least twice the length of the first region (L14). For example, the first region length (L14) may be 2 to 7 mm, and the second region length (L24) may be 10 to 15 mm. Preferably, the first region length (L14) may be at least 5 mm, and the second region length (L24) may be at least 13 mm, but is not limited thereto.

[0140] Additionally, although not shown in the drawing, other parts such as a side outer (SO) may be attached to the D-pillar (400). In this case, the side outer (SO) may be attached to the second region (A24) of the D-pillar (400) using the 'second attachment method' described above. As described above, by being attached in this way, the side outer (SO) can cover the outer side of the D-pillar (400).

[0141] In this case, the fourth inner member (410) and the fourth outer member (420) constituting the D-pillar (400) are joined together in the first area (A14), and additional parts such as the side outer (SO) can be joined separately in the second area (A24). Accordingly, the joining portion of the side outer (SO) forms a double weld in which only one flange and the side outer (SO) overlap and are welded, and even if additional parts are assembled therein, only a triple weld can be formed. That is, it is possible to prevent the formation of a four-layer weld on the D-pillar (400), and, as with the previously described embodiments, high strength can be secured while preventing an excessive increase in weight.

[0142] The D-pillar (400) described above may be extended along one direction. For example, the direction of extension of the D-pillar (400) may be the height direction of the vehicle or the vertical direction (Z). In this case, the D-pillar (400) may be extended in a straight line along the vertical direction (Z) between the second rear side rail (SR3) and the side sill (SS). At this time, the D-pillar (400) may be extended to have the same closed cross-section along its direction of extension [i.e., the vertical direction (Z)]. By doing so, the D-pillar (400) may have a shape having the same closed cross-section along its entire length.

[0143] To summarize again, the pillar section (PL), which includes the A pillar (100), B pillar (200), C pillar (300), and D pillar (400) as described above, can form a closed section by joining the first flange (112, 113, 212, 213, 312, 313, 412, 413) and the second flange (122, 123, 222, 223, 322, 323, 422, 423) provided at both ends of each pillar (100, 200, 300, 400) by contacting each other. Such a closed section can be extended with the same shape and area along the extension direction of each pillar (100, 200, 300, 400).

[0144] In addition, the mutually coupled first flange (112, 113, 212, 213, 312, 313, 412, 413) and the second flange (122, 123, 222, 223, 322, 323, 422, 423) have different lengths, so that the first flange (112, 113, 212, 213, 312, 313, 412, 413) and the second flange (122, 123, 222, 223, 322, 323, 422, 423) overlap in a first region (A11, A12, A13, A14), and the first flange (112, 113, 212, 213), A second region (A21, A22, A23, A24) may be formed in which only one of the 312, 313, 412, 413) or the second flange (122, 123, 222, 223, 322, 323, 422, 423) is disposed. In this way, the first flange (112, 113, 212, 213, 312, 313, 412, 413) and the second flange (122, 123, 222, 223, 322, 323, 422, 423) are joined in the first area (A11, A12, A13, A14), and additional parts such as a side outer (SO) are joined in the second area (A21, A22, A23, A24), thereby preventing the formation of four or more welded parts in the pillar portion (PL), thereby ensuring rigidity and minimizing weight at the same time.

[0145] Meanwhile, although the invention has been described with reference to an embodiment in which the A-pillar (100) and B-pillar (200) have the same or similar shape as the C-pillar (300) and D-pillar (400) have the same or similar shape as the A-pillar (100), the B-pillar (200), the C-pillar (300), and the D-pillar (400) may all have the same shape as another example, and as yet another example, only one of the pillars (100, 200, 300, 400) may have a different shape. The shape of these pillars (100, 200, 300, 400) may be changed depending on the type, shape, or side of the vehicle in which the pillar section (PL) is installed.

[0146] FIG. 9 is a side view illustrating a loop side rail according to an embodiment of the present invention. FIG. 10 (a) is a cross-sectional view taken in the direction C1-C1' of FIG. 9, and FIG. 10 (b) is a cross-sectional view taken in the direction C2-C2' of FIG. 9.

[0147] Referring to FIGS. 9 and 10, the roof side rail (RS) may extend along the front-rear direction (X) of the vehicle. At this time, the roof side rail (RS) may include at least partially extending in different directions.

[0148] For example, as illustrated in FIG. 9, the front side rail (SR1) may extend from the front of the vehicle toward the rear along a direction inclined toward the upper side. At this time, the front end of the first rear side rail (SR2) may be connected to the rear end of the front side rail (SR1), and the second rear side rail (SR3) may be connected to the rear end of the first rear side rail (SR2). The first rear side rail (SR2) and the second rear side rail (SR3) may extend along the front-rear direction (X) toward the rear of the vehicle from the aforementioned rear end of the front side rail (SR1). Hereinafter, for convenience of explanation, the first rear side rail (SR2) and the second rear side rail (SR3) will be referred to as the 'rear side rails (SR2, SR3)'.

[0149] The front side rail (SR1) and the rear side rails (SR2, SR3) can all have the same cross-sectional shape. Accordingly, the loop side rail (RS) can have the same closed cross-section throughout its extension direction.

[0150] More specifically, referring to FIG. 10 (a), the front side rail (SR1) may be a structure in which an inner member (hereinafter, fifth inner member) (510a) and an outer member (hereinafter, fifth outer member) (520a) are joined together to form a closed cross-section.

[0151] The fifth inner member (510a) may include a first body (511a) and a first flange (512a, 513a). Two first flanges (512a, 513a) are provided, and hereinafter, one of the two is referred to as the first-1 flange (512a) and the other of the two is referred to as the first-2 flange (513a).

[0152] The first body (511a) can have various shapes. That is, the first body (511a) can be provided in any shape as long as it includes the first flanges (512a, 513a) at both ends.

[0153] For example, the first body (511a) may be extended along the vertical direction (Z) and its lower end may be bent outward (+Y) to form a shape similar to an 'L'. In this case, a first-1 flange (512a) may be positioned protruding downward from the lower end of the body (511a). The first-1 flange (512a) may be extended in a straight line downward along the vertical direction (Z) from the lower end of the first body (511a). The following description focuses on the case where the first body (511a) is in the shape of an 'L', but the present invention is not limited thereto.

[0154] A first body (511a) may have a first-2 flange (513a) protruding upward from its upper portion. At this time, the upper portion of the first-2 flange (513a) may be bent in one direction. The first-2 flange (513a) may be bent toward the inner direction (-Y) of the vehicle, and the upper portion of the first-2 flange (513a) bent in this manner shall be referred to as the bent portion (514a). Accordingly, the first-2 flange (513a) may include a 'straight portion' extending in a straight line for a predetermined length toward the upper portion along the vertical direction (Z) from the upper portion of the first body (511a), and a 'bent portion (514a)' bent toward the inner direction (-Y) from the aforementioned straight portion.

[0155] A second flange (523a), which will be described later, is connected to such a straight section, and the roof of the vehicle can be connected to and supported at the bent section (514a).

[0156] The fifth outer member (520a) may include a second body (521a) and a second flange (522a, 523a). Two second flanges (522a, 523a) are provided, and hereinafter, one of the two is referred to as the second-1 flange (522a) and the other of the two is referred to as the second-2 flange (523a).

[0157] The second body (521a) can have various shapes. That is, the second body (511a) can be provided in any shape as long as it includes second flanges (522a, 523a) at both ends.

[0158] For example, the second body (521a) may be bent multiple times to form a hat or a similar shape protruding outward (+Y). In this case, a second-1 flange (522a) may be positioned protruding downward from the lower end of the body (521a). The second-1 flange (522a) may extend straight downward along the vertical direction (Z) from the lower end of the first body (521a). Additionally, a second-2 flange (523a) may be positioned protruding upward from the upper end of the second body (521a). The second-2 flange (513a) may extend straight upward along the vertical direction (Z) for a predetermined length from the upper end of the second body (521a).

[0159] In the above case, when the fifth inner member (510a) and the fifth outer member (520a) are combined, the first-1 flange (512a) and the second-1 flange (522a) can be joined through the 'first joining method' described above while in contact with each other. Also, the straight portion of the first-2 flange (513a) and the second-2 flange (523a) can be joined through the 'first joining method' described above while in contact with each other.

[0160] The first flange (512a, 513a) and the second flange (522a, 523a) may have different lengths from each other.

[0161] For example, the first-1 flange (512a) may have a longer length than the second-1 flange (522a). Also, the 'straight portion' of the first-2 flange (513a) may have a longer length than the second-2 flange (523a). Due to this difference in length, when the first inner member (510a) and the first outer member (520a) are combined, a 'first area (A15)' which is an area where the first flange (512a, 513a) and the second flange (522a, 523a) come into contact and overlap each other, and a 'second area (A25)' which is an area where only one of the first flange (512a, 513a) and the second flange (522a, 523a) is positioned can be formed.

[0162] More specifically, the front side rail (SR1) may have a 'first area (A15)' in which the first-1 flange (512a) and the second-1 flange (522a) are arranged together in contact, and a 'first area (A15)' in which the straight portion of the first-2 flange (513a) and the second-2 flange (523a) are arranged together in contact. Additionally, the front side rail (SR1) may have a 'second area (A25)' located at the bottom of the front side rail (SR1) in which only the first-1 flange (512a) is arranged, and a 'second area (A25)' located at the top of the front side rail (SR1) in which only the bent portion (514a) of the first-2 flange (512a) is arranged.

[0163] An empty space (E) may be formed inside the front side rail (SR1) formed by combining the above-mentioned fifth outer member (520a) and fifth inner member (510a).

[0164] The length of the second region (A25), the ‘second region length (L25)’, may be longer than the length of the first region (A15), the ‘first region length (L15)’. For example, the second region length (L24) may be more than twice the length of the first region (L14), but is not limited thereto.

[0165] The fifth inner member (510a) and the fifth outer member (520a) of the above form can be manufactured by bending a steel plate multiple times using a roll forming method, as described above or similarly. At this time, since the specific method of manufacturing the front side rail (SR1) using a roll forming method is similar to the manufacturing method of the A-pillar (100) described above, a detailed explanation thereof will be omitted.

[0166] In addition, the fifth inner member (510a) and the fifth outer member (520a) as described above can be combined to form a closed cross-section to form a front side rail (SR1).

[0167] In addition, although not shown in the drawing, other parts such as a side outer (SO) may be attached to the front side rail (SR1). At this time, as previously mentioned, the side outer (SO) can be attached to the second area (A25) using a 'second attachment method'. Accordingly, by preventing the formation of four-layer welding on the front side rail (SR1), when additional parts are attached to the second area (A25), not only can the high strength of the front side rail (SR1) be secured, but the weight can also be prevented from increasing excessively.

[0168] Referring to FIG. 10 (b), the rear side rails (SR2, SR3) may be structured such that an inner member (hereinafter, the sixth inner member) (510b) and an outer member (hereinafter, the sixth outer member) (520b) are joined together to form a closed cross-section.

[0169] In the case of the sixth inner member (510b), similar to the fifth inner member (510a) described above, the first body (511a) may be provided in various forms including two first flanges (512a, 513a). At this time, since the rear side rails (SR2, SR3) have the same shape as the front side rail (SR1) except for the extension direction, the first body (511b) of the sixth inner member (510b) may have the same shape as the first body (511a) of the fifth inner member (510a).

[0170] For example, if the first body (511a) of the fifth inner member (510a) is in the shape of an 'L', the first body (511a) may also be extended along the vertical direction (Z), and its lower end may be bent outward (+Y) to have a shape similar to an 'L'. In this case, a first-1 flange (512b) may be positioned protruding downward from the lower end of the body (511b). The first-1 flange (512b) may extend in a straight line downward along the vertical direction (Z) from the lower end of the first body (511b). Hereinafter, the description will focus on the case where the first body (511b) is in the shape of an 'L', but the present invention is not limited thereto.

[0171] Additionally, a first-2 flange (513b) may be positioned to protrude upward from the upper portion of the first body (511b). At this time, the first-2 flange (513a) includes a 'straight portion' and a 'folded portion (514b)' formed by bending the upper portion of the straight portion toward the inner direction (-Y), which is the same or similar as previously described.

[0172] A second flange (523b), which will be described later, is connected to such a straight section, and the roof of the vehicle can be supported and connected to the bent section (514b).

[0173] Additionally, the sixth outer member (520b) of the rear side rail (SR2, SR3) can be provided in various forms by manufacturing the second body (521b) by bending it multiple times, just like the fifth outer member (520a) described above. For example, the sixth outer member (520b) can be manufactured in a hat shape protruding outward (+Y) as described above. A second-1 flange (522b) may be positioned protruding downward at the lower end of the second body (521b), and a second-2 flange (523b) may be positioned protruding upward at the upper end of the second body (521b).

[0174] In the above case, when the 6th inner member (510b) and the 6th outer member (520b) are joined, the 1-1 flange (512b) and the 2-1 flange (522b) can be joined in a state of mutual contact using the '1st joining method'. Also, the straight portion of the 1-2 flange (513b) and the 2-2 flange (523b) can be joined in a state of mutual contact using the '1st joining method'.

[0175] At this time, the first flange (512b, 513b) and the second flange (522b, 523b) may have different lengths from each other.

[0176] For example, the first-1 flange (512b) may have a longer length than the second-1 flange (522b). Also, the 'straight section' of the first-2 flange (513b) may have a longer length than the second-2 flange (523b). Due to this difference in length, when the first inner member (510b) and the first outer member (520a) are combined, a 'first area (A16)' which is an area where the first flange (512b, 513b) and the second flange (522b, 523b) come into contact and overlap each other, and a 'second area (A26)' which is an area where only one of the first flange (512b, 513b) and the second flange (522b, 523b) is positioned can be formed.

[0177] More specifically, in the rear side rail (SR2, SR3), a 'first area (A16)' in which the first-1 flange (512b) and the second-1 flange (522b) are placed together in contact with each other, and a 'first area (A16)' in which the straight portion of the first-2 flange (513b) and the second-2 flange (523b) are placed together in contact with each other may be formed. Additionally, in the rear side rail (SR2, SR3), a 'second area (A26)' located at the bottom of the rear side rail (SR2, SR3) in which only the first-1 flange (512b) is placed, and a 'second area (A26)' located at the top of the rear side rail (SR2, SR3) in which only the bent portion (514b) of the first-2 flange (512b) is placed may be formed.

[0178] An empty space (E) may be formed inside the rear side rail (SR2, SR3) formed by combining the 6th outer member (520b) and the 6th inner member (510b).

[0179] The sixth inner member (510b) and the sixth outer member (520b) of the above form can be manufactured by bending a steel plate multiple times using a roll forming method, as described above or similarly. At this time, since the specific method of manufacturing the rear side rails (SR2, SR3) using a roll forming method is similar to the manufacturing method of the A-pillar (100) described above, a detailed explanation thereof will be omitted.

[0180] The sixth inner member (510b) and the sixth outer member (520b) as described above can be joined together to form a closed cross-section to form a rear side rail (SR2, SR3).

[0181] Although not shown in the drawing, other parts such as a side outer (SO) may be attached to the rear side rails (SR2, SR3). In this case, the side outer (SO) may be attached to the second area (A26) using a 'second attachment method'. By doing so, the formation of a four-layer weld on the rear side rails (SR2, SR3) is prevented, thereby ensuring high strength of the rear side rails (SR2, SR3) when additional parts are attached to the second area (A26), while simultaneously preventing an excessive increase in weight.

[0182] FIG. 11 is a perspective view illustrating a side seal according to one embodiment of the present invention and a cross-sectional view illustrating an enlarged portion of the side seal.

[0183] Referring to FIG. 11, the side seal (SS) can be formed by bending a plate multiple times. Accordingly, the side seal (SS) can be provided in various forms.

[0184] For example, the side sill (SS) may include a side sill body (611) having a shape similar to an 'L' when viewed from the side direction (e.g., the YZ plane direction). Additionally, the side sill (SS) may include an upper flange (612) positioned at the upper end of the side sill body (611). The upper flange (612) may be in a shape that protrudes upward along the vertical direction (Z) from the upper end of the side sill body (611).

[0185] The above side sill (SS) can be extended along the front-rear direction (X) of the vehicle. For example, as shown in FIG. 1, the side sill (SS) can be extended from the A-pillar (100) to the C-pillar (300). In this case, the aforementioned pillar portion (PL) can be attached to the upper flange (612), which will be described later.

[0186] FIG. 12 is a side view illustrating the vehicle body frame unit of FIG. 1 as seen from the other side. FIG. 13 schematically illustrates the A' area of ​​FIG. 1 as seen from the side. FIG. 14 schematically illustrates the A'' area of ​​FIG. 1 as seen from the side.

[0187] Referring to FIGS. 1 and 12, the body frame unit (10) may further include a connecting portion (Cb10, Cb20) that connects the pillar portion (PL) to the roof side rail (RS) or side sill (SS). At this time, the connecting portion (Cb10, Cb20) may include an upper connecting portion (Cb10) and a lower connecting portion (Cb20).

[0188] The upper connecting portion (Cb10) can connect the upper portion of the pillar portion (PL) to the loop side rail (RS). To this end, the upper connecting portion (Cb10) may include a plurality of upper connecting members (Cb11, Cb12, Cb13, Cb14). The upper connecting members (Cb11, Cb12, Cb13, Cb14) may include side flanges (Cb11s, Cb12s, Cb13s, Cb14s). Two side flanges (Cb11s, Cb12s, Cb13s, Cb14s) may be provided and disposed on each side of the upper connecting members (Cb11, Cb12, Cb13, Cb14).

[0189] Additionally, the lower connecting portion (Cb20) can connect the lower portion of the pillar portion (PL) to the side sill (SS). To this end, the lower connecting portion (Cb20) may include a plurality of lower connecting members (Cb21, Cb22, Cb23, Cb24). The lower connecting members (Cb21, Cb22, Cb23, Cb24) may include side flanges (Cb21s, Cb22s, Cb23s, Cb24s). Two side flanges (Cb21s, Cb22s, Cb23s, Cb24s) may be provided and disposed on each side of the lower connecting members (Cb21, Cb22, Cb23, Cb24).

[0190] The upper connecting members (Cb11, Cb12, Cb13, Cb14) described above are simultaneously connected to one side of the upper portion of the pillar portion (PL) and one side of the roof side rail (RS), thereby allowing the upper portion of the pillar portion (PL) to be fixed to the roof side rail (RS). Additionally, the lower connecting members (Cb21, Cb22, Cb23, Cb24) are simultaneously connected to one side of the lower portion of the pillar portion (PL) and one side of the side sill (SS), thereby allowing the lower portion of the pillar portion (PL) to be fixed to the side sill (SS).

[0191] For example, as illustrated in FIGS. 1 and 12, the lower end of the upper connecting member (Cb11, Cb12, Cb13, Cb14) may be connected to the outer surface of the upper end of the pillar part (PL) [e.g., the outer surface of the upper end of the outer member (120, 220, 320, 420)], and the upper end of the upper connecting member (Cb11, Cb12, Cb13, Cb14) may be connected to the outer surface of the loop side rail (RS) [e.g., the outer surface of the outer member (520a, 520b)]. And, the upper portion of the lower connecting member (Cb21, Cb22, Cb23, Cb24) can be connected to the outer surface of the lower portion of the pillar portion (PL) [e.g., the outer surface of the lower portion of the outer member (120, 220, 320, 420)], and the lower portion of the lower connecting member (Cb21, Cb22, Cb23, Cb24) can be connected to the outer surface of the side sill (SS) [e.g., the outer surface of the side sill body (611) and the upper flange (612)].

[0192] As another example, although not shown in the drawing, the lower end of the upper connecting member (Cb11, Cb12, Cb13, Cb14) may be connected to the inner surface of the upper end of the pillar part (PL) [e.g., the inner surface of the upper end of the inner member (110, 210, 310, 410)], and the upper end of the upper connecting member (Cb11, Cb12, Cb13, Cb14) may be connected to the inner surface of the loop side rail (RS) [e.g., the inner surface of the inner member (510a, 510b)]. And, the upper portion of the lower connecting member (Cb21, Cb22, Cb23, Cb24) can be connected to the inner surface of the lower portion of the pillar portion (PL) [e.g., the inner surface of the lower portion of the inner member (110, 210, 310, 410)], and the lower portion of the lower connecting member (Cb21, Cb22, Cb23, Cb24) can be connected to the inner surface of the side sill (SS) [e.g., the inner surface of the side sill body (611) and the upper flange (612)].

[0193] Hereinafter, for convenience of explanation, an embodiment in which an upper connecting member (Cb11, Cb12, Cb13, Cb14) and a lower connecting member (Cb21, Cb22, Cb23, Cb24) are connected to the outer surface of a pillar portion (PL) and the outer surface of a roof side rail (RS) or the outer surface of a side sill (SS) will be described.

[0194] For example, the upper connecting portion (Cb10) may include a first upper connecting member (Cb11), a second upper connecting member (Cb12), a third upper connecting member (Cb13), and a fourth upper connecting member (Cb14). And, the lower connecting portion (Cb20) may include a first lower connecting member (Cb21), a second lower connecting member (Cb22), a third lower connecting member (Cb23), and a fourth lower connecting member (Cb24).

[0195] In this case, the first upper connecting member (Cb11) can connect the upper portion of the A-pillar (100) to the lower portion of the front side rail (SR1). At this time, the lower portion of the first upper connecting member (Cb11) can be connected to the outer surface of the upper portion of the A-pillar (100), and the upper portion of the first upper connecting member (Cb11) can be connected to the outer surface of the lower portion of the front side rail (SR1). Additionally, the first lower connecting member (Cb21) can connect the lower portion of the A-pillar (100) to a part of the upper portion of the side sill (SS) (e.g., the front portion). At this time, the upper portion of the first lower connecting member (Cb21) can be connected to the outer surface of the lower portion of the A-pillar (100), and the lower portion of the first lower connecting member (Cb21) can be connected to the outer surface of the upper portion of the side sill (SS).

[0196] Similarly, the second upper connecting member (Cb12) can connect the upper portion of the non-pillar (200) to the lower portion of the first rear side rail (SR2). At this time, the lower portion of the second upper connecting member (Cb12) can be connected to the outer surface of the upper portion of the non-pillar (200), and the upper portion of the second upper connecting member (Cb12) can be connected to the outer surface of the lower portion of the first rear side rail (SR2). Additionally, the second lower connecting member (Cb22) can connect the lower portion of the non-pillar (200) to another part (e.g., the middle portion) of the upper portion of the side sill (SS). At this time, the upper portion of the second lower connecting member (Cb22) can be connected to the outer surface of the lower portion of the non-pillar (200), and the lower portion of the second lower connecting member (Cb22) can be connected to the outer surface of the upper portion of the side sill (SS).

[0197] The third upper connecting member (Cb13) can connect the upper portion of the C-pillar (300) to the lower portion of a part (e.g., the front portion) of the second rear side rail (SR3). At this time, the lower portion of the third upper connecting member (Cb13) can be connected to the outer surface of the upper portion of the C-pillar (300), and the upper portion of the third upper connecting member (Cb13) can be connected to the outer surface of the lower portion of the second rear side rail (SR3). Additionally, the third lower connecting member (Cb23) can connect the lower portion of the C-pillar (300) to another part (e.g., the rear portion) of the upper portion of the side sill (SS). At this time, the upper portion of the third lower connecting member (Cb23) can be connected to the outer surface of the lower portion of the C-pillar (300), and the lower portion of the third lower connecting member (Cb23) can be connected to the outer surface of the upper portion of the side sill (SS).

[0198] Additionally, the fourth upper connecting member (Cb14) can connect the upper portion of the D-pillar (400) to the lower portion of another part (e.g., the rear portion) of the second rear side rail (SR3). At this time, the lower portion of the fourth upper connecting member (Cb14) can be connected to the outer surface of the upper portion of the D-pillar (400), and the upper portion of the fourth upper connecting member (Cb14) can be connected to the outer surface of the lower portion of the second rear side rail (SR3). Furthermore, the fourth lower connecting member (Cb24) can connect the lower portion of the D-pillar (400) to the upper portion of a separate support member (not shown), rather than the side sill (SS). At this time, the upper portion of the fourth lower connecting member (Cb24) can be connected to the outer surface of the lower portion of the D-pillar (400), and the lower portion of the fourth lower connecting member (Cb24) can be connected to the outer surface of the upper portion of the support member. Meanwhile, as another embodiment, the fourth lower connecting member (Cb24) may be connected to the lower end of the D-pillar (400) to the upper end of the side sill (SS), rather than to the support member mentioned above.

[0199] Referring to FIG. 13, the specific method by which the upper connecting members (Cb11, Cb12, Cb13, Cb14) connect the pillar portion (PL) to the loop side rail (RS) may be as follows. Hereinafter, for convenience of explanation, the explanation will focus on the case where the upper portion of the non-pillar (200) is connected to the first rear side rail (SR2) by the second upper connecting member (Cb12).

[0200] As described above, the non-pillar (200) has a structure in which a second inner member (210) and a second outer member (220) are mutually combined. In this case, the upper portion (hereinafter referred to as the inner upper portion) (201) of the second inner member (210) may be formed at a different height from the upper portion (hereinafter referred to as the outer upper portion) (202) of the second outer member (220). More specifically, when combined with the first rear side rail (SR2), the inner upper portion (201) may have a height that abuts the lower portion of the first body (511b) of the sixth inner member (510b) of the first rear side rail (SR2). At this time, the inner upper portion (210) is welded in a state abutting the first body (511b), thereby allowing the inner upper portion (201) of the non-pillar (200) to be combined with the first rear side rail (SR2). Accordingly, a weld (Wd) can be formed between the inner upper part (201) and the lower part of the first body (511b).

[0201] On the other hand, the outer upper portion (202) has a lower height than the inner upper portion (201), so that it does not come into contact with the lower portion of the second body (521b) of the sixth outer member (520b) of the first rear side rail (SR2). Accordingly, the outer upper portion (202) and the second body (521b) are spaced apart from each other, and a gap can be provided between them. Within this gap, the first-1 flange (512b) and the second-1 flange (522b), which are joined together, can be extended along the downward direction (-Z). The first-1 flange (512b) and the second-1 flange (522b) can be extended up to just above the outer upper portion (202) within the aforementioned gap.

[0202] With the above configuration, the upper portion of the first rear side rail (SR2) and the non-pillar (200) can be connected by the second upper connecting member (Cb12). To this end, the second upper connecting member (Cb12) can be positioned between the sixth outer member (520b) and the outer upper portion (202).

[0203] More specifically, the upper portion of the second upper connecting member (Cb12) can cover at least partially the outer surface of the second body (521b) of the sixth outer member (520b). At this time, the upper portion of the second upper connecting member (Cb12) and the outer surface of the second body (521b) can be joined together by welding. By doing so, a weld (Wa) can be formed between the upper portion of the second upper connecting member (Cb12) and the outer surface of the second body (521b). Additionally, the lower portion of the second upper connecting member (Cb12) can cover at least partially the outer surface of the outer upper portion (202). At this time, the lower portion of the second upper connecting member (Cb12) and the outer surface of the outer upper portion (202) can be joined together by welding. Accordingly, a weld (Wc) can be formed between the lower part of the second upper connecting member (Cb12) and the outer surface of the outer upper part (202).

[0204] In the above case, the side flange (Cb12s) of the second upper connecting member (Cb12) may be positioned so that its upper end contacts the second area (A26) formed on the first rear side rail (SR2), and the lower end of the said side flange (Cb12s) contacts the upper end of the second area (A22) formed on the non-pillar (200). In this position, the side flange (Cb12s) may be joined to the second areas (A22, A26) by a 'second joining method'. By doing so, a weld (Wb) may be formed between the side flange and the second area (A22), and between the side flange (Cb12s) and the second area (A26).

[0205] As described above, the non-pillar (200) is formed with different lengths for the inner upper portion (201) and the outer upper portion (202), and the inner upper portion (201), which has a relatively longer length, can be connected to the roof side rail (RS). Accordingly, the weight of the non-pillar (200) can be reduced by the amount by which the length of the outer upper portion (202) is reduced. Additionally, the non-pillar (200) can be interconnected by using the second upper connecting member (Cb12) to cover and connect the outer upper portion (202), which has a relatively shorter length, with a part of the roof side rail (RS), thereby reinforcing the connection force between the non-pillar (PL) and the roof side rail (RS).

[0206] Meanwhile, as another embodiment, although not illustrated in the drawings, when the second upper connecting member (Cb12) is connected to the inner surface of the first rear side rail (SR2) and the non-pillar (200), the outer upper portion (202) may be formed at a higher height than the inner upper portion (201) described above. In this case, the second upper connecting member (Cb12) is coupled with the inner upper portion (201), which is relatively shorter in length, and at least a portion of the inner surface of the first rear side rail (SR2) simultaneously, thereby obtaining the weight reduction and bonding strength reinforcement effects described above.

[0207] Additionally, the upper end of the A-pillar (100) may be connected to the front side rail (SR1) by the first upper connecting member (Cb11), and the upper end of the C-pillar (300) may be connected to the rear end of the first rear side rail (SR2) by the third upper connecting member (Cb13). Also, the upper end of the D-pillar (400) may be connected to the second rear side rail (SR3) by the fourth upper connecting member (Cb14). Since the specific connection method and structure of these pillars (100, 300, 400) are identical or similar to the B-pillar (200) described above, a redundant description will be omitted.

[0208] Referring to FIG. 14, the specific method by which the upper connecting members (Cb11, Cb12, Cb13, Cb14) connect the pillar portion (PL) to the loop side rail (RS) may be as follows. Hereinafter, for convenience of explanation, the explanation will focus on the case where the upper portion of the non-pillar (200) is connected to the first rear side rail (SR2) by the second upper connecting member (Cb12).

[0209] The non-pillar (200) may have a long length such that the lower portion (hereinafter, inner lower portion) (203) of the second inner member (210) protrudes further in the downward direction (-Z) than the lower portion (hereinafter, outer lower portion) (204) of the second outer member (220). At this time, the outer lower portion (204) is spaced apart from the upper portion of the side sill body (611), thereby providing a spaced gap between the outer lower portion (204) and the upper portion of the side sill body (611). The upper flange (612) of the side sill (SS) may extend along the upward direction (+Z) into this spaced gap. The upper flange (612) may extend to just below the outer lower portion (204) within the spaced gap.

[0210] With the above configuration, the lower portions of the side sill (SS) and the non-pillar (200) can be connected by the second lower connecting member (Cb22). To this end, the second lower connecting member (Cb22) can be positioned between the side sill body (611) and the outer lower portion (202).

[0211] More specifically, the upper portion of the second lower connecting member (Cb22) can cover at least partially the outer surface of the outer lower portion (204). At this time, the lower portion of the second lower connecting member (Cb22) and the outer surface of the outer lower portion (204) can be joined to each other by welding. By doing so, a weld (Wc') can be formed between the lower portion of the second lower connecting member (Cb22) and the outer surface of the outer lower portion (205). Additionally, the lower portion of the second lower connecting member (Cb22) can cover at least partially the outer surface of the side sill body (611). At this time, the lower portion of the second lower connecting member (Cb22) and the outer surface of the side sill body (611) can be joined to each other by welding. Accordingly, a weld (Wa') can be formed between the lower end of the second lower connecting member (Cb22) and the outer surface of the side seal body (611).

[0212] In the above case, the side flange (Cb22s) of the second lower connecting member (Cb22) can be positioned so that its upper end contacts the lower end of the second region (A22) formed in the non-pillar (200), and the lower end of the side flange (Cb22s) contacts the upper flange (612) of the side sill (SS). With the side flange (Cb22s) positioned in this manner, it can be joined to the second region (A22) and the upper flange (612) by a 'second joining method'. By doing so, a weld (Wb') can be formed between the side flange (Cb22s) and the second region (A22), and between the side flange (Cb22s) and the upper flange (612).

[0213] As described above, the non-pillar (200) is joined to the side seal (SS) by the second lower connecting member (Cb22), thereby reducing the weight of the non-pillar (200) and simultaneously reinforcing the bonding force with the side seal (SS).

[0214] Additionally, the lower end of the A-pillar (100) may be connected to the front end of the side sill (SS) by the first lower connecting member (Cb21), and the lower end of the C-pillar (300) may be connected to the rear end of the side sill (SS) by the third lower connecting member (Cb23). Furthermore, the lower end of the D-pillar (400) may be connected to a separate support member (not shown) or the side sill (SS) by the fourth upper connecting member (Cb14). Since the specific connection method and structure of these pillars (100, 300, 400) are identical or similar to the B-pillar (200) described above, a redundant description will be omitted.

[0215] Pillars (100, 200, 300, 400) and a roof side rail (RS) as described above can be manufactured using a roll forming device (not shown). At this time, the method of manufacturing the pillars (100, 200, 300, 400) and the roof side rail (RS) according to one embodiment of the present invention may be as follows.

[0216] The roll forming device may include a first roll forming unit (not shown) and a second roll forming unit (not shown). The first roll forming unit and the second roll forming unit may be arranged side by side in a horizontal direction (e.g., left-right direction) and extend along the same direction.

[0217] Two plates can be supplied simultaneously to the roll forming device. One of the two plates, the first plate, can be supplied to the first roll forming unit, and the other of the two plates, the second plate, can be supplied to the second roll forming unit. After being supplied to the roll forming device, the first plate and the second plate can be transported in the same direction. The transport direction of the first and second plates may be the same direction as the extension direction of the first roll forming unit and the second roll forming unit. Meanwhile, the aforementioned horizontal direction may refer to the width direction of the first and second plates supplied to the device, and may mean a direction perpendicular to the transport direction.

[0218] For example, the first roll forming unit and the second roll forming unit may be provided as separate units. In this case, the first roll forming unit and the second roll forming unit may be arranged to face each other in the left-right direction and extended parallel to each other along the aforementioned extension direction to form a roll forming device. As another example, the first roll forming unit and the second roll forming unit may be provided as a single device. In this case, the first roll forming unit may form a part of the roll forming device, and the second roll forming unit may form a different part of the roll forming device.

[0219] The first roll forming unit may include a first front forming section and a first forming section.

[0220] The first front forming section is a part that bends and forms the first plate material, and may include a plurality of first front roller sets arranged in a row along the above-mentioned conveying direction.

[0221] The first front roller set may include a first pressing part for pressing at least a portion of the first plate to form a bend. The first pressing part may be formed in a protruding shape and / or a groove shape. In this case, the shape, location, and number of the first pressing part may be changed based on the target shape of the first plate being bent by the first front forming part [or the target shape of the pillars (100, 200, 300, 400) or the loop side rail (RS)].

[0222] When supplied to the first front roller set, the first plate passes through the first pressing portions of a plurality of first front forming portions along the conveying direction and can be bent and formed by gradually applying pressure. By this, first flanges (112, 212, 312, 412, 512a, 512b) can be formed at both ends of the first plate. That is, by the first front forming portion, an inner member (110, 210, 310, 410, 510a, 510b) having an open cross-section and including first flanges (112, 212, 312, 412, 512a, 512b) at both ends can be manufactured. The inner members (110, 210, 310, 410, 510a, 510b) may be manufactured in a hat shape, but are not limited thereto.

[0223] In the above case, the first pressure part and the second pressure part may be provided in the same or different forms. For example, if the pillars (100, 200, 300, 400) and the roof side rail (RS) are manufactured in a symmetrical shape, the first pressure part and the second pressure part may be provided in the same form. As another example, if the pillars (100, 200, 300, 400) and the roof side rail (RS) are manufactured in an asymmetrical shape, the first pressure part and the second pressure part may be provided in different forms.

[0224] The first forming section is a part that processes the first plate material formed by bending so that it rotates, and can be positioned downstream of the first front forming section with respect to the conveying direction.

[0225] The first forming section may include a plurality of first roller sets arranged in a row along the aforementioned conveying direction. The first roller sets may be positioned downstream of the first front roller set so as to be continuous with the first front roller set.

[0226] Accordingly, a plurality of first front roller sets and a plurality of first roller sets can be continuously arranged in a line along the conveying direction. The first plate material that has passed through the first front forming section can be rotated in the first forming section, and this will be described later.

[0227] Similarly, the second roll forming unit may include a second front forming section and a second forming section.

[0228] The second front forming section is a part that bends and forms the second plate material, and may include a plurality of second front roller sets arranged in a row along the aforementioned conveying direction.

[0229] The second front roller set may include a second pressing part for bending and forming at least a portion of the second plate by pressing. The second pressing part may be formed in a protruding shape and / or a groove shape. In this case, the shape, location, and number of the second pressing part may be changed based on the target shape of the second plate being bent by the first front forming part [or the target shape of the pillars (100, 200, 300, 400) or the loop side rail (RS)].

[0230] When supplied to the second front roller set, the second plate passes through the second pressing sections of a plurality of first front forming sections along the conveying direction and can be bent and formed by gradually applying pressure. By this, second flanges (113, 213, 313, 413, 513a, 513b) can be formed at both ends of the second plate. That is, by the second front forming section, an outer member (120, 220, 320, 420, 520a, 520b) having an open cross-section and including second flanges (113, 213, 313, 413, 513a, 513b) at both ends can be manufactured. The outer members (120, 220, 320, 420, 520a, 520b) may be manufactured in a hat shape, but are not limited thereto.

[0231] The second forming section is a part that processes the second plate material, which has been bent, to rotate, and can be positioned downstream of the second front forming section with respect to the conveying direction.

[0232] The second forming section may include a plurality of second roller sets arranged in a row along the aforementioned transfer direction. The second roller sets may be positioned downstream of the first front roller set so as to be continuous with the second front roller set.

[0233] Accordingly, a plurality of second front roller sets and a plurality of second roller sets can be continuously arranged in a line along the conveying direction. The first plate material that has passed through the first front forming section can be rotated in the first forming section, and this will be described later.

[0234] In the above case, the first front forming section and the second front forming section are arranged side by side in the aforementioned left-right direction, and the first forming section and the second forming section may be arranged side by side in the aforementioned left-right direction. In this state of being arranged side by side, the first plate and the second plate can be supplied simultaneously to the first front forming section and the second front forming section.

[0235] After passing through the first and second front forming sections as described above, the first plate material can be supplied to the first forming section, and the second plate material can be supplied to the second forming section.

[0236] The first plate can pass through a plurality of first roller sets provided in the first forming section along the conveying direction. During this process, the first plate can gradually rotate toward the second plate.

[0237] When pressurized between the first roller sets, the first plate may be sandwiched between the first roller sets so as to be inclined at a predetermined angle (hereinafter referred to as the first angle) with respect to the width direction described above. At this time, as the first forming section moves from upstream to downstream, the plurality of first roller sets may be configured such that the first angle gradually increases. Accordingly, the first plate may gradually rotate to approach the second plate while passing through the plurality of first roller sets along the conveying direction.

[0238] Similarly, the second plate can pass through a plurality of second roller sets provided in the second forming section along the conveying direction. During this process, the second plate can gradually rotate toward the first plate.

[0239] When pressurized between the second roller sets, the second plate may be sandwiched between the second roller sets so as to be inclined at a predetermined angle (hereinafter referred to as the second angle) with respect to the width direction described above. At this time, as the second forming section moves from upstream to downstream, the plurality of second roller sets may be configured such that the second angle gradually increases. Accordingly, the second plate may gradually rotate to approach the first plate while passing through the plurality of second roller sets along the conveying direction.

[0240] In the above case, the shape of the first roller set and / or the second roller set, the size of the first angle and / or the second angle, or the degree to which the first angle and / or the second angle increases in the conveying direction may be changed based on the target shape of the pillars (100, 200, 300, 400) or the loop side rail (RS) being manufactured.

[0241] Meanwhile, when manufacturing a loop side rail (RS), as the bending forming step by the aforementioned first and second front forming parts and the rotational processing step by the first and second forming parts are performed, at least one upper part of the first-2 flange (513) and the second-2 flange (523) may be bent to form a bent portion (514).

[0242] When the rotational processing of the first plate and the second plate is completed in the manner described above, the first plate and the second plate may be in a 'contact state' in which at least a portion is in contact. The contact portions of the plates may be the first flange (112, 212, 312, 412, 512a, 512b) and the second flange (113, 213, 313, 413, 513a, 513b). That is, the contact state may mean a state in which the first flange (112, 212, 312, 412, 512a, 512b) of the inner member (110, 210, 310, 410, 510a, 510b) and the second flange (113, 213, 313, 413, 513a, 513b) of the outer member (120, 220, 320, 420, 520a, 520b) are in one-to-one contact.

[0243] Meanwhile, the aforementioned bending forming and rotational processing may be performed at least partially simultaneously. That is, the first plate and the second plate may gradually rotate toward each other while the bending forming is in progress. However, the present invention is not limited thereto, and the bending forming and rotational processing may be performed at different times. That is, rotational processing may begin after the bending processing of the first plate and the second plate is completed.

[0244] The plates in contact can be continuously transported along the transport direction. At this time, the plates in contact can be transported while being pressed by the first roller set and the second roller set.

[0245] While being transported under pressure in this manner, the contact portions of the plates can be welded and joined by a joining unit. More specifically, the joining unit continuously irradiates a laser beam at a specific point along the transport path of the plates, and the first flange (112, 212, 312, 412, 512a, 512b) and the second flange (113, 213, 313, 413, 513a, 513b) that are in contact with each other pass through the aforementioned specific point and can be welded by the laser.

[0246] In this manner, the first-1 flanges (112, 212, 312, 412, 512a, 512b) located on both sides of the plates in contact are welded together with the second-1 flanges (122, 222, 322, 422, 522a, 522b), and the first-2 flanges (113, 213, 313, 413, 513a, 513b) are welded together with the second-2 flanges (123, 223, 323, 423, 523a, 523b), thereby forming a first weld (Wb1). At this time, the first weld (Wb1) is formed in the first region (A10) as described above.

[0247] When welding is completed in the manner described above, the first plate and the second plate are joined together to form a single structure having a closed cross-section and a long length. Even after welding is completed, the structure can be pressed by roller sets positioned downstream of the roll forming device. In this way, by pressing the welded flanges (112, 212, 312, 412, 512a, 512b, 113, 213, 313, 413, 513a, 513b), thermal deformation such as warping of the plate caused by laser welding can be prevented.

[0248] Meanwhile, when supplying the plates, the distance between the first plate and the second plate in the width direction described above can be adjusted. For example, the first plate and the second plate may be supplied in a state where they are almost in contact in the width direction, or, as another example, the first plate and the second plate may be supplied in a state where they are separated by a predetermined distance in the width direction.

[0249] In this way, when supplied with the distance between the plates adjusted, the steps of bending, rotational processing, and welding can be performed as the first plate and the second plate move along the conveying direction while maintaining the adjusted distance. At this time, the position and shape of the plates being bent can be adjusted based on whether the first plate and the second plate are separated and the change in the distance between them. Additionally, the contact area between the first flange (112, 212, 312, 412, 512a, 512b) and the second flange (113, 213, 313, 413, 513a, 513b) can be varied so that the position and area of ​​the first region (A10) and the second region (A20) can be adjusted. By doing so, various types of pillars (100, 200, 300, 400) and roof side rails (RS) can be manufactured using a single roll forming device without changing the device.

[0250] Subsequently, by cutting the above-mentioned structure to a predetermined length, unit structures or pillars (100, 200, 300, 400) with adjusted lengths and a loop side rail (RS) can be manufactured. Additionally, various types of pillars (100, 200, 300, 400) and a loop side rail (RS) can be manufactured by preparing a number of the unit structures cut to a predetermined length, arranging them to extend in different directions, and then reassembling them.

[0251] The method of manufacturing the pillars (100, 200, 300, 400) and the loop side rail (RS) according to another embodiment of the present invention may be as follows.

[0252] The roll forming device may include a first roll forming unit (not shown) and a second roll forming unit (not shown) arranged to face each other in the vertical direction and extending parallel along a first conveying direction. Additionally, the roll forming device may further include a shearing unit (not shown) and a joining unit (not shown).

[0253] The first roll forming unit may be extended to a longer length than the second roll forming unit based on the first conveying direction. At this time, the roll forming device may include a roll forming section in which the front part of the first roll forming unit and the second roll forming unit are arranged together to form an inner member (110, 210, 310, 410, 510a, 510b) and an outer member (120, 220, 320, 420, 520a, 520b) by bending.

[0254] Additionally, the roll forming device may further include a transition section located behind the aforementioned roll forming section, in which the conveying direction of any one of the inner member (110, 210, 310, 410, 510a, 510b) and the outer member (120, 220, 320, 420, 520a, 520b) that has completed bending forming is switched to a second conveying direction. Furthermore, the roll forming device may further include a coupling section located behind the aforementioned transition section, in which the inner member (110, 210, 310, 410, 510a, 510b) and the outer member (120, 220, 320, 420, 520a, 520b) are conveyed together in a first conveying direction and coupled to each other. Such roll forming sections, transition sections, and joining sections can be provided continuously along the first transfer direction.

[0255] For example, the first roll forming unit may receive a first plate in the form of a coil and perform bending forming processing to manufacture an inner member (110, 210, 310, 410, 510a, 510b). At this time, the first roll forming unit may include a plurality of upper rolls and lower rolls arranged in a row along a first conveying direction. The first plate may be bent and formed by passing between the plurality of upper rolls and lower rolls along the first conveying direction and being gradually pressed. By doing so, a first flange (112, 212, 312, 412, 512a, 512b) is formed on each side of the first plate, thereby, for example, a hat-shaped inner member (110, 210, 310, 410, 510a, 510b) may be manufactured.

[0256] In addition, the second roll forming unit can receive a second plate in the form of a coil and perform bending forming processing to manufacture an outer member (120, 220, 320, 420, 520a, 520b). At this time, the second roll forming unit may include a plurality of upper rolls and lower rolls arranged in a row along a first conveying direction. The second plate can be bent and formed by passing between the plurality of upper rolls and lower rolls along the first conveying direction and being gradually pressed. By doing so, a second flange (113, 213, 313, 413, 513a, 513b) is formed on each side of the second plate, thereby manufacturing, for example, a hat-shaped outer member (120, 220, 320, 420, 520a, 520b).

[0257] In the above case, a portion of the second plate may be sheared by a shearing unit before entering the roll forming section. The sheared portion (hereinafter referred to as the narrow portion) may have a narrower width compared to other parts of the second plate that are not sheared. Additionally, when the narrow portion of the second plate passes through the second roll forming unit, it may not come into contact with the upper roll and the lower roll due to its narrow width. As a result, even after the bending process of the second plate is completed, the narrow portion of the second plate may have a flat plate shape without any bent portion. Due to having such a shape, the narrow portion may have lower rigidity than other parts of the outer member (120, 220, 320, 420, 520a, 520b) (e.g., the part where the second flange is formed).

[0258] Additionally, a plurality of narrow sections may be spaced apart and formed in the outer members (120, 220, 320, 420, 520a, 520b). When the bending forming is completed, the outer members (120, 220, 320, 420, 520a, 520b) may have a long, extended shape in which second flanges (113, 213, 313, 413, 513a, 513b) are arranged between the aforementioned plurality of narrow sections.

[0259] The bending forming process of the roll forming method described above can be performed in the aforementioned roll forming section. In addition, the bending forming process of the first roll forming unit and the bending forming process of the second roll forming unit can be performed simultaneously.

[0260] After passing through the roll forming section, the inner members (110, 210, 310, 410, 510a, 510b) can continue to move along the first conveying direction, pass through the transition section, and enter the joining section.

[0261] On the other hand, when the outer members (120, 220, 320, 420, 520a, 520b) enter the transition section, the transfer direction may be switched to a second transfer direction. As the second roll forming unit is spaced apart from the first roll forming unit in the up-down or left-right direction, the second transfer direction may be a direction inclined upward, downward, left, or right relative to the first transfer direction.

[0262] After the transfer direction is switched, the outer members (120, 220, 320, 420, 520a, 520b) can move along the second transfer direction, pass through the transition section, and be transferred to the rear end of the first roll forming unit placed within the coupling section. At this time, prior to entering the coupling section, the transfer direction of the outer members (120, 220, 320, 420, 520a, 520b) can be switched back to the first transfer direction.

[0263] In this way, when the transfer direction is switched and re-switched, the outer member (120, 220, 320, 420, 520a, 520b) moves while partially bending because the second transfer direction is inclined with respect to the first transfer direction. At this time, the outer member (120, 220, 320, 420, 520a, 520b) may have its transfer direction switched or re-switched as the narrow section and the adjacent section, which have relatively low rigidity, bend. By including the narrow section in this manner, damage such as buckling can be prevented from occurring in the outer member (120, 220, 320, 420, 520a, 520b) when the transfer direction is switched.

[0264] Then, the inner members (110, 210, 310, 410, 510a, 510b) and the outer members (120, 220, 320, 420, 520a, 520b) can be transported along the first transport direction in a superimposed state after meeting at the joint section. At this time, the inner member (110, 210, 310, 410, 510a, 510b) and the outer member (120, 220, 320, 420, 520a, 520b) can be moved while being pressed by a plurality of upper rolls and lower rolls arranged at the rear end of the first roll forming unit, with the first flange (112, 212, 312, 412, 512a, 512b) and the second flange (113, 213, 313, 413, 513a, 513b) in contact with each other in a one-to-one manner. In this process, the first flange (112, 212, 312, 412, 512a, 512b) and the second flange (113, 213, 313, 413, 513a, 513b) can be joined by the joining unit. For example, the joining unit can perform a joining process to form a first weld (Wb1) by using a joining laser welding method (i.e., a first joining method) that irradiates a laser beam into a first region (A10) formed by the contact of the first flange (112, 212, 312, 412, 512a, 512b) and the second flange (113, 213, 313, 413, 513a, 513b).

[0265] In this way, a single long structure having a closed cross-section can be formed. Subsequently, a unit structure (100, 100-2) or an A-pillar (100) having a predetermined length can be manufactured by cutting the single structure at a position corresponding to a narrow section to adjust the length. Additionally, various types of A-pillars (100) can be manufactured by preparing a number of the unit structures (100, 100-2) cut to a predetermined length, arranging them to extend in different directions, and then recombining them.

[0266] As described above, the body frame unit (10) according to the embodiments of the present invention is formed such that the pillar portion (PL) and the roof side rail (RS) are formed with a first area (A11, A12, A13, A14, A15, A16) in which the inner members (110, 210, 310, 410, 510a, 510b) and the outer members (120, 220, 320, 420, 520a, 520b) are mutually coupled, and a second area (A21, A22, A23, A24, A25, A26) in which additional parts such as side outer (SO) are coupled, thereby reducing the number of welding layers when coupling additional parts.

[0267] As a result, not only can welding defects and strength reduction caused by an excessive increase in the number of welding layers, such as four-layer welding, be prevented, but additional processing steps, such as trimming of the outer panel parts to avoid four-layer welding, are also unnecessary, and sufficient strength can be secured while reducing the weight of the pillar part (PL) and the body frame unit (10).

[0268] In addition, since the pillar section (PL) and the side rail (RS) are formed in a shape having a closed cross-section of the same shape and size along each extension direction, when manufacturing the vehicle body frame unit (10), it is possible to easily implement changes in the shape of the pillar section (PL) and the side rail (RS) in response to various shapes of the vehicle body, thereby improving productivity during mass production of the product and securing the effect of reducing manufacturing costs.

[0269] Although embodiments of the present invention have been described above with reference to the attached drawings, those skilled in the art will understand that the present invention may be implemented in other specific forms without changing its technical concept or essential features. Therefore, the embodiments described above should be understood as illustrative in all respects and not restrictive.

[0270] (Explanation of symbols)

[0271] 10: Body frame unit RS: Roof side rail

[0272] PL: Pillar SR1: Front side rail

[0273] 100: A-pillar SR2: 1st rear side rail

[0274] 200: B-pillar SR3: 2nd rear side rail

[0275] 300: C-pillar SS: Side sill

[0276] 400: Di Pilar

Claims

1. A roof side rail positioned on the side of the vehicle body and supporting the roof; A side sill positioned below the above-mentioned loop side rail and supporting the lower part of the vehicle body; and A pillar section disposed between the above-mentioned loop side rail and the above-mentioned side sill and comprising a plurality of pillars; The above-mentioned loop side rail and the above-mentioned pillar are, It includes an inner member comprising a first flange having a first length and arranged to protrude outwardly from one end, and an outer member comprising a second flange having a second length different from the first length and arranged to protrude outwardly from one end, facing the first flange. The inner member and the outer member are, A vehicle body frame unit in which the first flange and the second flange are joined in contact with each other to form a closed cross-section, and the closed cross-section extends with the same area along the extension direction of the pillar.

2. In Paragraph 1, The first flange and the second flange are each provided in two numbers, The two first flanges are each disposed at both ends of the inner member, and A vehicle body frame unit having two second flanges each disposed at both ends of the outer member and facing one-to-one with two first flanges.

3. In Paragraph 1, When the inner member and the outer member are combined, A vehicle body frame unit having a first area in which the first flange and the second flange are arranged together so as to overlap, and a second area in which only one of the first flange and the second flange is arranged.

4. In Paragraph 3, The first flange and the second flange are, A vehicle body frame unit that is joined in a first joining method in the first area above to form the closed cross-section above.

5. In Paragraph 4, In the second area above, a body frame unit in which a side outer is connected by a second connecting method.

6. In Paragraph 3, The above-mentioned second region is a body frame unit having a longer length than the above-mentioned first region.

7. In Paragraph 6, The length of the first region is 2 to 7 mm, and A vehicle body frame unit having a second region of length of 10 to 15 mm.

8. In Paragraph 3, The above-mentioned loop side rail is, Two first flanges are provided on the inner member, one of the two first flanges is arranged to protrude downward from the lower end of the inner member, and the other of the two first flanges is arranged to protrude upward from the upper end of the inner member. A vehicle body frame unit having two second flanges provided on the outer member, wherein one of the two second flanges is positioned to protrude downward from the lower end of the outer member, and the other of the two second flanges is positioned to protrude upward from the upper end of the outer member.

9. In Paragraph 8, The inner member of the above-mentioned loop side rail is, A vehicle body frame unit comprising a bent portion formed by bending the first flange that is positioned to protrude upward.

10. In Paragraph 8, The above pillar is, A vehicle body frame unit having the upper portion of the inner member and the upper portion of the outer member at different heights.

11. In Paragraph 10, The upper portion of the inner member protrudes higher than the upper portion of the outer member, and When the above loop side rail and the above pillar are combined, A body frame unit, wherein the upper portion of the inner member of the pillar is coupled to the inner member of the roof side rail, and the upper portion of the outer member of the pillar is spaced apart from the outer member of the roof side rail.

12. In Paragraph 10, A vehicle body frame unit further comprising a connecting portion when connecting the inner member or the outer member of the above pillar to the roof side rail and the side sill.

13. In Paragraph 12, The upper portion of the inner member protrudes higher than the upper portion of the outer member, and The above connecting part is, A vehicle body frame unit arranged to simultaneously cover at least one part of the outer member of the above pillar and at least one part of the outer member of the above roof side rail.

14. In Paragraph 13, A vehicle body frame unit, wherein the upper portion of the above-mentioned connecting portion is coupled to the outer surface of the outer member of the above-mentioned pillar, and the lower portion of the above-mentioned connecting portion is coupled to the outer surface of the above-mentioned outer member of the above-mentioned roof side rail.

15. In Paragraph 14, The above connecting part is, It includes a side flange that protrudes outward from one side, and The above side flange is, A body frame unit coupled to at least one of the second area of ​​the roof side rail and the second area of ​​the pillar.

16. In Paragraph 12, The upper portion of the outer member protrudes higher than the upper portion of the inner member, and The above connecting part is, A vehicle body frame unit arranged to simultaneously cover at least one part of the inner member of the pillar and at least one part of the inner member of the roof side rail.

17. In Paragraph 16, A vehicle body frame unit, wherein the upper portion of the connecting portion is coupled to the inner surface of the inner member of the pillar, and the lower portion of the connecting portion is coupled to the inner surface of the inner member of the roof side rail.

18. In Paragraph 17, The above connecting part is, It includes a side flange that protrudes outward from one side, and The above side flange is, A body frame unit coupled to at least one of the second area of ​​the roof side rail and the second area of ​​the pillar.

19. In Paragraph 12, The above side seal is, A vehicle body frame unit comprising a plate that is bent at least twice to form an open cross-section, and an upper flange that is positioned to protrude upward from the upper portion thereof.

20. In Paragraph 19, A body frame unit in which the upper portion of the above-mentioned connecting part is connected to the pillar, and the lower portion of the above-mentioned connecting part is connected to the side sill.

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