Door beam structure for side door of vehicle and manufacturing method thereof

Abstract

This invention provides a door beam structure for a vehicle side door. The door beam structure for a vehicle side door of this invention includes a door beam (8) having a hollow cross-section, characterized in that it includes: an outer portion (15) of a hollow flange portion (17) forming the door beam (8) on the door panel side; and an inner portion (16) of a hollow door beam body portion (18) forming the door beam (8). Accordingly, the door beam structure for a vehicle side door exhibits excellent impact absorption performance during a collision and achieves lightweight design.

Description

Technical Field

[0001] This invention relates to a door beam structure for a vehicle side door and its manufacturing method. Background Technology

[0002] In the prior art, a door beam structure for a vehicle side door is known, wherein the door beam is configured to extend along the inner side of the door skin (see, for example, Patent Document 1). This door beam is a tubular component obtained by roll forming of a steel sheet, and in a cross-sectional view intersecting the length direction, it has a closed cross-sectional shape with two connected sections. Specifically, the cross-section of the door beam is formed into a generally isosceles trapezoid by arranging two symmetrical right-angled trapezoids. Furthermore, the door beam is configured such that the upper base (short side) of the upper and lower bases constituting the isosceles trapezoid faces the door skin. Accordingly, the two legs constituting the isosceles trapezoid are inclined such that the distance between them gradually decreases as they approach the door skin.

[0003] According to this door beam structure, when a collision load is input into the door from the outside of the vehicle, the deformation of the door beam is suppressed by the portion of the door beam corresponding to the waist of the inclined trapezoid, thereby improving the resistance to collision.

[0004] Existing technical documents

[0005] Patent documents

[0006] Patent Document 1: Japanese Patent Publication No. 2010-149841 Summary of the Invention

[0007] However, the existing portal beam structure (for example, see Patent Document 1) has the following problem: the overall weight of the portal beam increases because the steel plates overlap vertically in the partition wall portions where the closed cross-sectional shapes of the upper and lower double-connected sections face each other.

[0008] Therefore, the technical problem to be solved by the present invention is to provide a side door beam structure for a vehicle with excellent impact absorption performance during collision and the ability to achieve lightweight door beam, and a method for manufacturing the same.

[0009] A door beam structure for a vehicle side door used to solve the aforementioned technical problem includes a door beam with a hollow cross-section, characterized in that it comprises: an outer portion of a hollow flange portion of the door beam formed on the door panel side; and an inner portion of a hollow door beam body portion forming the door beam.

[0010] Furthermore, the method for manufacturing a side door beam structure for a vehicle to solve the aforementioned technical problem is characterized by having a blow molding process, in which gas is supplied into a steel tube heated in a mold to cause the steel tube to expand, thereby pressurizing and forming the door beam having the outer portion and the inner portion within the mold.

[0011] Invention Effects

[0012] According to the present invention, a side door beam structure for a vehicle with excellent impact absorption performance during a collision and a lightweight door beam structure and a method thereof are provided. Attached Figure Description

[0013] Figure 1 This is a side view of a car door using the door beam structure described in the embodiments of the present invention.

[0014] Figure 2 yes Figure 1 Sectional view II-II.

[0015] Figure 3 This is a three-dimensional view of the entire lintel.

[0016] Figure 4A From Figure 3 A top view of the portal lintel as observed from the IVa direction.

[0017] Figure 4B From Figure 3 A side view of the portal beam as observed in the IVb direction.

[0018] Figure 5A yes Figure 4A or Figure 4B Va-Va sectional view.

[0019] Figure 5B yes Figure 4A or Figure 4B Vb-Vb cross-sectional view.

[0020] Figure 6 This is a magnified 3D view of a protruding part in the lintel.

[0021] Figure 7 This is a schematic diagram showing the gradually changing closed section structure in a portal beam.

[0022] Figure 8 This is a structural diagram illustrating the gate beam manufacturing device.

[0023] Figure 9 This is an illustration of the blow molding process for the door lintel.

[0024] Figure 10This is a time-varying diagram of the portal beam cross-section under collision load input.

[0025] Figure 11 It is a graph showing the relationship between the impactor's travel, the input load on the portal beam, and the energy absorbed by the portal beam.

[0026] Figure 12 This is a side view showing a modified example of a door beam, and is related to... Figure 4B The corresponding diagram.

[0027] Explanation of reference numerals in the attached figures

[0028] 1: Door beam structure; 4: Door panel; 5: Door hinge; 6: Locking hook; 8: Door beam; 15: Outer part; 16: Inner part; 17: Flange; 18: Door beam main body; 19: Reinforcing ridge; 20: Transverse bead; 24: Protrusion; 31: Mold; 33: Pipe (steel pipe). Detailed Implementation

[0029] Next, the door beam structure used to implement the present invention (this embodiment) will be described in detail. The main feature of the door beam structure in this embodiment is that the door beam has a hollow door beam body portion (inner portion) and a hollow flange portion (outer portion) disposed on the door panel side. Furthermore, as will be explained in detail later, the door beam in this embodiment is constructed from a tubular compression molded body.

[0030] Figure 1 This is a side view of the left-side side door 2 of a vehicle that uses the door beam structure 1 described in this embodiment. Figure 2 yes Figure 1 Sectional view II-II. Furthermore, the front-back, up-down, left-right directions in this embodiment are consistent with the front-back, up-down, left-right directions of the vehicle. Figure 1 For ease of drafting, door panel 4 is omitted (see reference). Figure 2 ).

[0031] The following description focuses only on the door beam structure 1 applied to the left side door 2 of the vehicle, omitting the description of the door beam structure 1 applied to the right side door 2, which is symmetrical to the right side door 2 across the vehicle's central axis.

[0032] <Side door>

[0033] like Figure 1 As shown, the side door 2 of the door beam structure 1 has: a front side door 2a for opening and closing the front opening of the side of the vehicle (not shown); and a rear side door 2b for opening and closing the rear opening of the side of the vehicle (not shown).

[0034] The front side door 2a has an inner panel 3a and an outer side in the vehicle width direction disposed on the inner panel 3a. Figure 1 Door panel 4 (refer to the front side of the paper) Figure 2 Furthermore, it is envisioned that the door panel 4 in this embodiment is arranged at a predetermined interval from the inner panel 3a, and is joined to the periphery of the inner panel 3a by a folded edge process.

[0035] The inner panel 3a has a first reinforcing member 7 and a first door beam 8a. The first door beam 8a, together with the second door beam 8b of the rear side door 2b (described next), is equivalent to a "door beam" in the technical solution.

[0036] The first reinforcing member 7 is an elongated member, which is arranged in a front-to-back direction on the upper part of the inner panel 3a at the lower edge of the window 11a.

[0037] The first door beam 8a is positioned below the first reinforcing member 7, extending in a front-to-back direction between the front and rear edges of the inner panel 3a. Specifically, the first door beam 8a is inclined in a manner that gradually shifts downward as it extends rearward.

[0038] Furthermore, as will be explained in detail later, the first door beam 8a in this embodiment extends in such a way as the upper door hinge 5 of the pair of upper and lower door hinges 5, 5 of the side door 2a and the engaging hook 6 that engages with the vehicle body when the side door 2a is closed.

[0039] The rear side door 2b has an inner panel 3b and a door panel (not shown), which is positioned on the outer side of the inner panel 3b in the vehicle width direction. Figure 1 (The paper surface near the front), and the door panel 4 of the side door 2a (refer to) Figure 2 Similarly, it is joined to the inner panel 3b through a folding process.

[0040] The inner panel 3b has a second reinforcing member 9, a third reinforcing member 10, and a second door beam 8b.

[0041] The second reinforcing member 9 is an elongated member, positioned above the inner panel 3b at the lower edge of the window 11b in a front-to-back direction.

[0042] The third reinforcing member 10 is positioned below the second reinforcing member 9, extending in a front-to-back direction between the front and rear edges of the inner panel 3b. Specifically, the third reinforcing member 10 is inclined such that it gradually shifts downward as it extends rearward. Furthermore, in this embodiment, the third reinforcing member 10 extends substantially parallel to the second door beam 8b.

[0043] The second door beam 8b (door beam) is inclined below the third reinforcing member 10 in a manner that gradually shifts downward as it extends rearward. In addition, in this embodiment, the second door beam 8b extends across the lower door hinge of the pair of upper and lower door hinges (not shown) of the side door 2b and the engaging hook 6 that engages with the vehicle body when the side door 2b is closed.

[0044] Furthermore, in this embodiment, the first portal beam 8a and the second portal beam 8b are... Figure 1 The vehicle body side view shown is configured in a manner that extends along the line connecting the upper front end of the inner panel 3a and the lower rear end of the inner panel 3b (illustration omitted).

[0045] In addition, without specifically distinguishing between side doors 2a and 2b, inner panels 3a and 3b, and door beam 8a and door beam 8b, they are sometimes simply referred to as side door 2, inner panel 3, and door beam 8, respectively.

[0046] <Portal Beam Structure>

[0047] Next, the front side door 2a (refer to...) Figure 1 The first portal beam 8a (refer to) Figure 1 Taking the portal beam structure 1 of this embodiment as an example (refer to...), Figure 1 (This will be explained in detail.)

[0048] As Figure 1 Sectional view II-II Figure 2 As shown, the door beam structure 1 of this embodiment is configured to have a door beam 8 disposed between the door panel 4 and the inner panel 3 of the side door 2. Furthermore, in Figure 2 In the diagram, for ease of drawing, an imaginary line (double-dotted line) is used to represent the door hinge part 5.

[0049] The door beam 8 is located on the outer side of the side door 2 when closed, along the vehicle width direction. Figure 2 The door panel 4 extends to the inner wall surface on the left side. Specifically, except for the front and rear ends of the door beam 8, the general portion 8c of the door beam 8, which occupies most of its length direction, is curved slightly outward in the vehicle width direction according to the curvature of the curved surface that protrudes outward in accordance with the curvature of the curved surface that protrudes outward in accordance with the curvature of the curved surface that protrudes outward in the door panel 4.

[0050] in addition, Figure 2 The gap between the door panel 4 and the general portion 8c of the door beam 8 shown is exaggerated. In this embodiment, the door panel 4 and the general portion 8c of the door beam 8 are tightly attached by adhesive sealant (not shown).

[0051] Furthermore, in this embodiment, the front end of the door beam 8 is joined to the inner panel 3 via the door hinge reinforcement member 13. In addition, in this embodiment, the rear end of the door beam 8 is joined to the inner panel 3 via the reinforcement member 14 of the engaging hook 6 (engaging member).

[0052] Next, for door beam 8 (refer to...) Figure 2 To explain in more detail.

[0053] Figure 3 This is a three-dimensional view of the entire lintel 8. Figure 4A From Figure 3 A top view of the portal beam 8 as observed from the IVa direction. Figure 4B From Figure 3 A side view of the portal beam 8 as observed in the IVb direction. Figure 5A yes Figure 4A or Figure 4B Va-Va sectional view. Figure 5B yes Figure 4A or Figure 4B Vb-Vb cross-sectional view.

[0054] like Figure 3 As shown, the portal beam 8 is formed by a tubular body with a hollow cross section (closed cross section).

[0055] In this embodiment, the door beam 8 has an outer portion 15, which is located on the door panel 4 (refer to...). Figure 2 The hollow flange portion 17 of the door beam 8 is formed on the side; and the inner portion 16 forms the hollow door beam body portion 18 of the door beam 8.

[0056] Specifically, the lintel 8 is shaped like a brim in a cross-sectional view intersecting the length direction. That is, the lintel 8 has: a lintel body portion 18, which corresponds to the raised portion of the brim shape; and a flange portion 17, which corresponds to the brim portion of the brim shape. Furthermore, the hollow portion of the flange portion 17 and the hollow portion of the lintel body portion 18 are continuous.

[0057] Refer to the following side. Figure 5A and Figure 5B The closed cross-sectional shape of this portal beam 8 is described in detail.

[0058] like Figure 3 As shown, on the outer portion 15 of the door beam 8, a part is formed that is consistent with the door panel 4 (see reference). Figure 2 The outer surface 21 facing each other. This outer surface 21 is equivalent to the "facing surface with the door panel" in the technical solution.

[0059] Furthermore, on the main body 18 of the lintel 8, which forms the inner portion 16, a side wall 23 is defined in a manner corresponding to the side of the raised portion in the shape of the finial, and an inner surface 22 is defined in a manner corresponding to the top surface of the raised portion. In addition, the side wall 23 is equivalent to the "wall of the main body of the lintel" in the technical solution.

[0060] like Figure 4A As shown, a reinforcing ridge 19 and a transverse ridge 20 are formed on the outer surface 21 of the door beam 8.

[0061] The reinforcing ridge 19 is formed at the center of the lintel 8 in the length direction, extending along the length direction.

[0062] As Figure 4A Va-Va sectional view Figure 5A As shown, the reinforcing ridge 19 is formed by a partial recess in the plate of the outer surface 21 of the door beam 8. Accordingly, the reinforcing ridge 19 protrudes partially toward the hollow portion 25 of the door beam 8 and is strip-shaped.

[0063] Furthermore, a groove 19a extending along the length direction of the door beam 8 is formed on the outer surface 21 of the door beam 8 in a manner corresponding to the reinforcing ridge 19.

[0064] Figure 5A In the attached diagram, the reference numeral V is represented by an imaginary line (double-dotted line). Figure 4A The outline of the door beam 8 at VV.

[0065] In addition, such as Figure 5A As shown, the outer contour V of the door beam 8 is an isosceles trapezoidal shape formed by a flat outer surface 21 and inner surface 22 in the vertical direction and a pair of sidewalls 23. Furthermore, flange portions 17 are formed at both ends of the outer surface 21 in the vertical direction, corresponding to the lower base (long side) of the isosceles trapezoidal shape. In this embodiment, the two flange portions 17 are formed such that they extend inward in the vehicle width direction, moving away from the isosceles trapezoidal door beam body 18 in the vertical direction. Figure 5A The right side of the curve is curved back.

[0066] And, as Figure 5A As shown, in relation to the outer contour V of this door beam 8, the depth of the groove 19a corresponding to the reinforcing ridge 19 is represented by D1.

[0067] Furthermore, it is envisioned that the reinforcing ribs 19 in this embodiment are arranged in two rows in the vertical width direction of the door beam 8, but it is not limited to this, and can also be one row or three or more rows. In addition, the reinforcing ribs 19 can also be formed outward in the vehicle width direction ( Figure 5A (The protruding strip on the left side).

[0068] like Figure 4A As shown, the transverse convex rib 20 is formed in a manner orthogonal to the length direction of the door beam 8.

[0069] As Figure 4A Vb-Vb cross-section Figure 5B As shown, the transverse ridge 20 is formed by partially recessing the outer surface 21 of the lintel 8 from the outline V of the lintel 8 to a depth D2. Accordingly, the transverse ridge 20 protrudes partially toward the hollow portion 25 of the lintel 8 and is strip-shaped. Furthermore, a groove 19b orthogonal to the length direction of the lintel 8 is formed on the outer surface 21 of the lintel 8 in a manner corresponding to the transverse ridge 20.

[0070] In addition, such as Figure 5B As shown, on the outer portion 15 where the groove 19b corresponding to the transverse convex ridge 20 is formed, the hollow portion of the flange portion 17 in this embodiment is also ensured to have a thickness TH such that it will not disappear due to the groove 19b.

[0071] like Figure 4A As shown, these transverse convex ribs 20 are formed in multiple arrangements along the length of the door beam 8.

[0072] However, in this embodiment, the transverse ridge 20 is formed on the outer surface 21 of the door beam 8, except for the central portion of the door beam 8 where the reinforcing ridge 19 is formed.

[0073] Furthermore, in this embodiment, it is preferable that the transverse ridge 20 is formed on the portion other than the two ends of the door beam 8 along its length, but these are not shown in the figure. In particular, it is preferable that the transverse ridge 20 is formed on... Figure 2 The general part 8c of the lintel 8 shown.

[0074] like Figure 4B As shown, protrusions 24 are formed on the side wall 23 of the door beam 8 in a manner that arranges multiple protrusions along the length of the door beam 8.

[0075] As Figure 4B Vb-Vb cross-section Figure 5B As shown, the protrusion 24 is formed to protrude from the outline V of the door beam 8 with a protrusion height P.

[0076] Figure 6 This is a magnified three-dimensional view of the protrusion 24 in the lintel 8.

[0077] like Figure 6 As shown, the protrusion 24 is approximately perpendicular to the outer surface 21 and consists of three surfaces: a first surface 24a and a pair of second surfaces 24b. The first surface 24a has a planar shape that is an isosceles triangle; the second surfaces 24b extend from a defined outline V (refer to...). Figure 5A and Figure 5BThe reference surface 24c of the side wall 23 of the first surface 24a is raised and connected to a pair of equal sides of the first surface 24a, and the planar shape is trapezoidal.

[0078] However, the protrusion 24 can be configured to have at least three surfaces, as long as it does not come into contact with the mold 31 (see below) during demolding. Figure 9 Interference can occur, and it can also be composed of more than 4 surfaces.

[0079] These protrusions 24 and transverse ridges 20 are arranged in a direction orthogonal to the length of the lintel 8. That is, Figure 4B The phase of the center line C in the front-rear direction of the protrusion 24 shown is consistent with that of the transverse convex ridge 20.

[0080] Furthermore, as will be explained in detail later, the lintel 8 can also be configured as follows: Figure 4B The phase of the center line C in the front-rear direction of the protrusion 24 shown is opposite to the phase of the transverse ridge 20 (see reference). Figure 12 ).

[0081] Next, the closed section gradient structure in portal beam 8 will be explained.

[0082] As will be explained in detail later, the door beam 8 in this embodiment is composed of a tubular compression molded body. That is, as described above, the perimeter of the door beam 8 in this embodiment, which is composed of a tubular body with a cap-shaped cross-section, is set to be the same as the perimeter of the tubular material (steel pipe) that is the raw material for the door beam 8.

[0083] Figure 7 This is a schematic diagram showing the closed cross-section gradient structure in portal beam 8.

[0084] like Figure 7 As shown, in this embodiment, the width direction of the door beam 8 is ( Figure 7 The height of the lintel 8 in the left-right direction gradually decreases as it moves from the center towards the end. Furthermore, the vertical width of the lintel 8 gradually increases as it moves from the center towards the end. That is, in any cross-sections Cs1, Cs2, and Cs3 arranged from the center towards the end of the lintel 8, the heights H1, H2, and H3 at each point satisfy the relationship H1 > H2 > H3, and the vertical widths W1, W2, and W3 at each point satisfy the relationship W1 < W2 < W3.

[0085] In addition, in this embodiment, the lintel 8 is based on the premise that its perimeter is constant in its length direction, and the extension length (width) L1, L2, L3 of the flange portion 17 at each of the cross sections Cs1, Cs2, and Cs3 satisfies the relationship L1 > L2 > L3.

[0086] <Manufacturing Method of Portal Beam Structure>

[0087] Next, for the portal beam structure 1 (refer to...) Figure 1 The manufacturing method of ) will be explained.

[0088] Next, let's first discuss door beam 8 (refer to...) Figure 3 The manufacturing apparatus for ( ) will be described.

[0089] Figure 8 This is a structural diagram illustrating the gate beam manufacturing device 30.

[0090] like Figure 8 As shown, the door beam manufacturing device 30 is mainly composed of: a blow molding die 31, which is formed by creating a door beam 8 (see reference) on its inner side. Figure 3 The cavity is formed by an upper mold 31a and a lower mold 31b; an electrode 32 energizes a tube 33 (a steel pipe as the raw material for the door beam) disposed in the blow molding mold 31; an air supply mechanism 34 supplies gas into the tube 33; and a pressing mechanism 35 presses the air supply mechanism 34 to the end of the tube 33.

[0091] According to the door beam manufacturing apparatus 30, the tube 33 is energized by the electrode 32, and the tube 33 is softened by the Joule heat generated in the tube 33. On the other hand, high-pressure gas is intermittently supplied into the tube 33 via the gas supply mechanism 34, which is pressed to the end of the tube 33 by the pressing mechanism 35. The tube 33, which is arranged between the upper mold 31a and the lower mold 31b, expands accordingly. Then, the upper mold 31a and the lower mold 31b are closed, and a hollow door beam 8 is blow-formed in the blow molding die 31. In addition, according to the door beam manufacturing apparatus 30, when the upper mold 31a and the lower mold 31b are closed, the resulting door beam 8 is subjected to mold contact cooling. Accordingly, the blow molding process and the quenching process of the door beam 8 are performed simultaneously or in parallel.

[0092] Next, the door beam 8 (refer to) made using blow molding mold 31 (hereinafter referred to as mold 31) Figure 3 The molding process (blow molding process) will be explained.

[0093] Figure 9 This is an explanatory diagram of the blow molding process for door beam 8.

[0094] like Figure 9 As shown in the upper part, in this molding process, a door beam 8 is arranged between the upper mold 31a and the lower mold 31b (see reference). Figure 1 The pipe fitting 33 is made of raw material, for example, a steel type that can undergo a martensitic phase transformation upon cooling. Additionally, in this embodiment, the upper mold 31a mimics a form having a protrusion 24 (see reference). Figure 5B The main body of the lintel 18 (refer to) Figure 5B ) and flange 17 (refer to Figure 5BThe inner half of the body. Additionally, in this embodiment, a reinforcing ridge 19 (see reference 19) is formed in the lower mold 31b. Figure 5A ) and transverse convex ridge 20 (refer to) Figure 5A The flange portion 17 (refer to) Figure 5A The outer half of the body.

[0095] Next, as described above, the fitting 33 is heated, and then high-pressure gas is supplied into the fitting 33 to cause it to expand. Then, as... Figure 9 As shown in the middle, as the upper mold 31a and the lower mold 31b gradually close, the tube 33 undergoes plastic deformation in a manner that follows the shape of the inner wall surface (cavity) of the mold 31.

[0096] And, as Figure 9 As shown in the lower part, the upper mold 31a and the lower mold 31b are completely closed, forming a door beam 8 in the cavity of the mold 31. The door beam 8 is composed of a tube with a closed cross section in the shape of an eaves cap formed with a specified wall thickness.

[0097] Next, regarding the portal beam structure 1 involved in this embodiment (refer to...), Figure 1 In the manufacturing method of ), the mold 31 (refer to) Figure 9 The removed door beam 8 (refer to) Figure 9 The two ends of the door beam 8 are processed into a specified shape. Specifically, the ends of the door beam 8 are shaped by laser cutting to fit into the inner panel 3 (see reference). Figure 2 The shape of the joint of the specified parts.

[0098] And, as Figure 2 As shown, in this embodiment, the front end of the door beam 8 is joined to the inner panel 3 via the door hinge reinforcement member 13. Furthermore, the rear end of the door beam 8 is joined to the inner panel 3 via the reinforcement member 14 of the engaging hook 6 (engaging member). Also, the outer surface 21 of the door beam 8 (see reference...) Figure 2 ) is bonded to door panel 4 (see reference) using adhesive sealant (illustration omitted). Figure 2 The inner wall surfaces of the components are joined together.

[0099] In addition, such as Figure 2 As shown, the front end of the door beam 8, which overlaps with the door hinge reinforcement 13 and the inner panel 3 in three layers, is fastened to the rotating side end of the door hinge 5.

[0100] Furthermore, the three overlapping portions of the rear end of the door beam 8, the reinforcing member 14 of the engaging hook 6 (engaging component), and the inner panel 3 are fastened together with the engaging hook 6 by bolts B or the like. Accordingly, the door beam structure 1 of this embodiment (refer to...) Figure 1 The manufacturing process of ) is completed.

[0101] <Effects>

[0102] Next, the effects of the portal beam structure 1 and its manufacturing method involved in this embodiment will be explained.

[0103] Unlike the existing door beam structure (for example, see Patent Document 1), in the door beam structure 1 of this embodiment, the door beam 8 has a hollow door beam body portion 18 in the inner portion 16 and a hollow flange portion 17 in the outer portion 15 facing the door panel 4.

[0104] According to this portal beam structure 1, it has excellent impact absorption performance during collision and can achieve lightweight portal beam.

[0105] Figure 10 This is a time-varying diagram of the portal beam cross-section under collision load input.

[0106] like Figure 10 As shown in the left figure, the outer portion 15 of the door beam 8, which has a hollow flange 17, is disposed on the side of the door panel 4.

[0107] When the load F from a side collision of a vehicle is input into this portal beam structure 1, such as Figure 10 As shown in the middle diagram, the hollow flange 17 in the outer portion 15 of the portal beam 8 deforms while generating a reaction force relative to the load F. Accordingly, the flange 17 can help absorb the impact energy in the first half of a side collision.

[0108] Next, as Figure 10 As shown in the right figure, after the flange 17 is crushed, the main body 18 of the lintel 8 in the inner part 16 bends, thereby absorbing the impact energy.

[0109] Figure 11 This indicates the impact travel [Stroke (mm)] and the gantry beam 8 (reference). Figure 3 A graph showing the relationship between the input load [Force(kN)] and the energy absorption [EA(kJ)] of the portal beam 8.

[0110] Figure 11 The graphs shown represent the test results of the portal beams involved in the embodiments of the present invention and the portal beams involved in the comparative examples.

[0111] The portal beam in the embodiment uses a design with Figure 5A and Figure 5B The cross-sectional shape shown has a maximum width of 69 mm vertically, a maximum width of 44.5 mm horizontally, and a wall thickness of 1.6 mm for the lintel. In contrast, the comparative example lintel uses a circular tube with an outer diameter of 35 mm and a wall thickness of 3.3 mm. Furthermore, the lintels of the embodiments and comparative examples are identical in material and length, except for the cross-sectional shape as described above. Additionally, the weight per unit length of the lintels of the embodiments and comparative examples is the same.

[0112] like Figure 11 As shown, it is verified that the energy absorption of the portal beam in the embodiment is greater than that of the portal beam in the comparative example.

[0113] Furthermore, it was verified that the door beam of the embodiment showed a sharper increase in the initial reaction force relative to the input impact load compared to the door beam of the comparative example.

[0114] In addition, the comparative example's door beam is in Figure 11 The white arrow in the diagram indicates the location where the beam broke midway through the stroke; in contrast, the lintel in the embodiment did not break midway.

[0115] In addition, the door beam structure 1 in this embodiment has a reinforcing ridge 19 formed in the center of the door beam 8.

[0116] According to this portal beam structure 1, when a collision load is input to the portal beam 8, the initial reaction force relative to the collision load is greater compared to a structure without the reinforcing ridge 19. Furthermore, this portal beam structure 1 can reduce deformation concentration in the central part of the portal beam 8, thereby preventing fracture in the central part.

[0117] In addition, in this lintel structure 1, multiple transverse convex ribs 20 are formed on the lintel 8.

[0118] According to this portal beam structure 1, multiple transverse ridges 20 arranged along the length of the portal beam 8 suppress the breakage of the central portion of the inner portion 16 of the portal beam 8 due to deformation of the outer portion 15 induced by the input load. That is, the transverse ridges 20 are used to adjust the fracture mode from the smaller cross-sectional area of ​​the inner portion 16 to the larger cross-sectional area of ​​the outer portion 15. Accordingly, the portal beam structure 1 can improve the absorption of impact energy during a side collision.

[0119] In addition, in this lintel structure 1, a plurality of protrusions 24 are formed on the side wall surface 23 of the main body 18 of the lintel.

[0120] According to this portal beam structure 1, during the first half of a side collision, when the hollow part of the flange 17 is crushed and touches the side wall surface 23, the side wall surface 23 of the inner part 16 with the protrusion 24 generates a large reaction force against the input load.

[0121] In addition, in this lintel structure 1, the transverse ridge 20 and the protrusion 24 are arranged in a direction orthogonal to the length direction of the lintel 8.

[0122] According to this portal beam structure 1, it is possible to efficiently absorb impact energy over a large range covering the length direction of the portal beam 8 and from the outer portion 15 to the inner portion.

[0123] In addition, in this lintel structure 1, the extension length (width) of the flange portion 17 gradually shortens as it approaches the two ends from the center of the lintel 8.

[0124] According to this lintel structure 1, in a lintel 8 with a fixed perimeter, as the extension length (width) of the flange portion 17 shortens at the ends, the thickness (height) in the vehicle width direction can be ensured. Accordingly, the lintel structure 1 can further improve the support strength at both ends of the lintel 8.

[0125] In addition, in this door beam structure 1, the front end of the door beam 8 is fixed to the door hinge part 5, and the rear end is fixed to the locking hook 6.

[0126] According to this portal beam structure 1, the support strength at both ends of the portal beam 8 is improved, which can effectively absorb the impact energy during side collisions.

[0127] In addition, in this lintel structure 1, the transverse ridge 20 is formed at locations other than the two ends of the lintel 8 along its length.

[0128] According to this door beam structure 1, by omitting the formation of the transverse protrusions 20 at both ends of the door beam 8, the actual height of the door beam 8 in the vehicle width direction can be increased, thereby improving the support strength at both ends of the door beam 8.

[0129] In addition, the door beam structure 1 is configured such that the adhesive sealant is placed between the door beam 8 and the door panel 4.

[0130] According to this door beam structure 1, the outer portion 15 facing the door panel 4 is wider than the inner portion 16 due to the formation of the flange portion 17, thereby ensuring a larger contact area for the adhesive sealant. Accordingly, the door beam structure 1 can improve the surface rigidity of the door panel 4 and enhance the vibration damping performance of the side door 2. Furthermore, because this door beam structure 1 ensures a larger contact area for the adhesive sealant, a separate bracket for the adhesive sealant is not required.

[0131] In addition, the manufacturing method of the door beam structure 1 involved in this embodiment includes the blow molding process of the door beam 8.

[0132] According to this manufacturing method, shapes that cannot be manufactured in existing roll forming techniques, such as the hollow flange portion 17 and the protrusion 24 of the main body portion 18 of the door beam, can be obtained. Furthermore, according to this manufacturing method, the forming and quenching processes for the hollow door beam 8 can be performed, thereby enabling the production of a lightweight door beam 8 with high strength.

[0133] The embodiments of the present invention have been described above, but the present invention is not limited to the described embodiments and can be implemented in various other ways.

[0134] Figure 12This is a side view showing a modified example of the portal beam 8, which is related to... Figure 4B The corresponding diagram.

[0135] like Figure 12 As shown, in the modified example, the protrusions 24 and transverse ridges 20 of the door beam 8 are arranged in a staggered manner along a direction orthogonal to the length direction of the door beam 8. That is, the phase of the center line C in the front-rear direction of the protrusions 24 is opposite to the phase of the transverse ridges 20. In other words, the transverse ridges 20 are formed at the midpoint of the center line C of adjacent protrusions 24.

[0136] According to this portal beam structure 1, the portal beam 8 is more reliable and less prone to breakage due to impact energy.

Claims

1. A door beam structure for a side door of a vehicle, comprising a door beam having a hollow section, characterized by: including: an outer side portion of a flange portion of the door beam that forms a hollow on a door panel side; and an inner side portion of a door beam main body portion that forms a hollow of the door beam, a transverse ridge is formed on a facing surface of the outer side portion that faces the door panel in a manner that a plurality of the transverse ridges are arranged in a length direction of the door beam, the transverse ridges being orthogonal to the length direction of the door beam.

2. The door beam structure for a side door of a vehicle according to claim 1, characterized by: a reinforcing ridge is formed on the facing surface of the outer side portion that faces the door panel in a manner that the reinforcing ridge extends in the length direction of the door beam in a central portion of the length direction of the door beam.

3. The door beam structure for a side door of a vehicle according to claim 1, characterized by: a protruding portion having at least three surfaces is formed on a wall surface of the door beam main body portion that extends in the length direction of the door beam and in an inner-outer side direction in a manner that a plurality of the protruding portions are arranged in the length direction of the door beam.

4. The door beam structure for a side door of a vehicle according to claim 3, characterized by: the transverse ridges and the protruding portions are arranged in a direction that is orthogonal to the length direction of the door beam.

5. The door beam structure for a side door of a vehicle according to claim 3, characterized by: the transverse ridges and the protruding portions are arranged in a direction that is orthogonal to the length direction of the door beam in a manner that the transverse ridges and the protruding portions are staggered with each other.

6. The door beam structure for a side door of a vehicle according to claim 1, characterized by: a width of the flange portion gradually becomes shorter as the width approaches both end portions from a central portion of the length direction of the door beam.

7. The door beam structure for a side door of a vehicle according to claim 1, characterized by: a front end side of the door beam is fixed to a door hinge portion, and a rear end side is fixed to a latching hook.

8. The door beam structure for a side door of a vehicle according to claim 1, characterized by: the transverse ridges are formed at a portion other than both end portions of the length direction of the door beam.

9. A manufacturing method of the door beam structure for a side door of a vehicle according to claim 1, characterized by: having a blow molding process in which a steel pipe that is heated in a mold is supplied with a gas to expand the steel pipe, thereby pressure forming the door beam having the outer side portion and the inner side portion in the mold.

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