JP3549607B2 - Vehicle door beam and method of manufacturing the same - Google Patents

Description

[0001]
[Industrial applications]
The present invention relates to a door beam that is mounted in a front-rear direction in an internal space between a door outer panel and a door inner panel in order to suppress an amount of deformation of a door toward a vehicle cabin during a side collision of an automobile and enhance occupant protection, and a manufacturing method thereof. About the method. In the case of a two-door vehicle and a hard-top vehicle, in addition to the door, the one that is attached to the inner space of the outer panel and the inner panel of the fender portion is also treated as a door beam in the present application, and is included.
[0002]
[Prior art]
Conventional door beams include, for example, JP-A-63-270223, JP-A-4-238725, JP-A-4-238726, JP-A-4-238727, JP-A-52-112025 and As shown in Japanese Utility Model Application Laid-Open No. 62-78519, a terminal member for attachment formed as a separate member is connected to both ends of a beam body formed in a tubular shape, or a tubular body is formed in a tubular shape. Expand both ends of the beam main body from the seam line into a single wall structure and connect the mounting end part continuously, or simply crush both ends of the tubular beam main body from the radial direction to form a flat plate There are known various structures in which a mounting terminal portion is integrally formed.
[0003]
[Problems to be solved by the invention]
However, in the conventional beam body in which both end members are joined to the end members of the separate members, the joint portion is lower than the strength of the base material, so the load applied from the side at the time of a side collision causes the joint portion between the beam body and the mounting portion to be joined. There is a possibility of peeling, and in the case where both ends of the beam main body are developed into a single wall structure and the terminal part is continuously connected, the load applied from the side at the time of side collision causes the beam base seam line from the deployment base of the terminal part If the end of the beam body is crushed to form an end portion, an unreasonable internal stress occurs during the crushing process, and the width of the mounting portion is reduced by (beam diameter × π (2) Since the dimensions are # 2, there is a problem that the dimensions for mounting to the vehicle body panel are limited, and when any of them is required to have higher strength and stable quality, it cannot sufficiently respond.
[0004]
Therefore, the present invention makes it possible to form the end portions of the double-walled structure for attachment at both ends of the central portion as the beam body continuously and integrally without causing excessive internal stress by using a pipe made of a high-tensile steel plate. It is another object of the present invention to provide a vehicle door beam capable of improving strength and rigidity and a method of manufacturing the same.
[0005]
[Means for Solving the Problems]
Claim 1 is a door beam made of a pipe made of a high-tensile steel plate attached in the front-rear direction to an internal space between an outer panel and an inner panel on a side portion of a vehicle, wherein the beam is a central beam forming a beam main body. Part and a mounting terminal part formed integrally and continuously with the longitudinal end of the central part, and the terminal part has a wall whose thickness gradually becomes thinner toward the tip from the central part. The elliptical fan-shaped section whose cross-section is gradually expanded toward the tip than the center and the width in the short-diameter direction is gradually reduced toward the tip rather than the center. It consists of a thin wall at the tip and a plate-shaped part that is formed to the maximum width of the fan-shaped part by overlapping each other.The plate-like portion has a cutout in a portion of one wall, and a portion of the other wall corresponding to the cutout is formed as a portion to be attached to a vehicle body panel.It is characterized by:
[0006]
According to a second aspect, the two walls of the plate-shaped portion according to the first aspect are fixed to each other.
[0008]
Claim3, Claim 1Or 2The pipe described in (1) is formed of an electric resistance welded pipe, and its suture line is arranged substantially at the center in the width direction of the terminal portion.
[0009]
Claim4, Claim 13Wherein the overlapping surfaces of the two walls of the plate-like portion are shifted radially from the center of the central portion.
[0010]
Claim5, Claim 13Wherein the overlapped surfaces of the two walls of the plate-like portion are substantially coincident with the center of the central portion.
[0011]
Claim6In the step of expanding the end portion of the pipe made of high-strength steel plate radially outward and plastically processing into a substantially trumpet shape in which the thickness is gradually reduced, and the trumpet-shaped portion is formed into an oval cross section. And a step of superimposing walls facing each other at the narrower edge at the edge of the elliptical portion.
[0012]
Claim7A step of expanding the end portion of the pipe made of a high-tensile steel plate toward the outside in the axial direction and plastically processing the pipe into a substantially trumpet shape in which the wall thickness gradually decreases, and a part of the annular edge of the trumpet-like portion Notching in a range not to exceed half in the circumferential direction, plastically processing the trumpet-shaped portion so as to have an elliptical cross-section, and facing the narrower edge at the edge of the oval-shaped portion And a step of polymerizing the wall to be formed.
[0013]
Claim8Claims6, 7In the process of plastic working into a trumpet shape as described in, pressing the pressing tool against the inner surface of the end portion of the pipe while rotating the pipe in the circumferential direction and applying a pressing force in the radial direction and relatively moving the pressing tool and the pipe It is characterized by using a spinning process for moving the pipe outward in the axial direction.
[0014]
Claim9Claims6-8As a step prior to the step of plastic working in the shape of a trumpet described in (1), the hardness of at least the plastically processed portion in the shape of a trumpet is reduced by annealing.
[0015]
Claim10Claims6-8The plastic working is characterized in that at least the plastically processed part of the trumpet shape is heated to reduce the hardness of the plastic working part.
[0016]
[Action]
According to the first aspect, the width of {(diameter × π)} 2 of the wide width of the double wall structure in which the mounting end portions at both ends of the central portion are overlapped via the fan-shaped portion having a cross section of an elliptical shape. Since it is formed in a wide plate-like part, the mounting dimensions to the main body panel can be made large, so that the mounting strength when mounting by welding etc. can be increased and the door beam does not generate excessive internal stress at the terminal part. Strength and rigidity can be increased.Further, by fixing the portion to be mounted remaining in the cutout portion to the door panel, even when the double-walled structure portion exceeds twice the thickness of the door panel, a substantially thin one-piece portion can be formed. The mounting portion can be appropriately joined to the door panel. This facilitates management of welding conditions when fixing by spot welding.
[0017]
According to the second aspect, since the two walls of the plate-shaped portion are fixed to each other, opening of the terminal portion can be prevented.
[0019]
Claim3According to the method, the pipe suture line is disposed substantially at the center in the width direction of the plate-shaped portion. Therefore, at the time of a side collision of the vehicle, it is difficult for cracks to enter from the suture line portion, and the rigidity of the door beam is improved.
[0020]
Claim4According to this, the overlapping surface of the plate portion is shifted in the radial direction from the center of the central portion, so that the entire area of the terminal portion can be attached to the door panel by overlapping.
[0021]
Claim5According to this, since the overlapped surface of the plate-shaped portion is made substantially coincident with the center of the central portion, the amount of projection to the outer panel side with respect to the plate-shaped portion can be substantially reduced to half of the diameter. Moldability is improved.
[0022]
Claim6According to the above, the end portion consisting of a fan-shaped portion and a plate-shaped portion having an oblong cross section at both ends of the central portion can be integrally formed without generating excessive internal stress, and a door beam having high strength and rigidity Can be easily obtained.
[0023]
Claim7According to this, a door beam having a high joining strength with the door panel can be obtained by the notch processing.
[0024]
Claim8According to the method, since the spinning process is used for the trumpet-shaped plastic working, the terminal portion can be expanded and thinned without cracks or the like.
[0025]
Claim9According to the method described above, the hardness of the terminal portion is reduced by performing an annealing process as a pre-process of the trumpet-shaped plastic working, so that the terminal portion can be easily expanded and thinned with a small force.
[0026]
Claim10According to the method, since the hardness of the terminal portion is reduced by heating during the trumpet-shaped plastic working, the terminal portion can be easily expanded and thinned with a small force.
[0027]
【Example】
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
[0028]
In FIGS. 1 to 7, reference numeral 1 denotes a door beam which is attached to an inner space 15 between a door inner panel 13 and a door outer panel 14 of a vehicle door 12 in a front-rear direction. The door beam 1 of the door inner panel 13 to which the door beam 1 is attached is attached. A central portion 2 which is a circular pipe made of an electric resistance welded tube made of a high-tensile steel plate having a thickness T larger than the thickness t, and has a thickness T which forms a beam main body having a constant diameter D; End portions 3 are integrally formed continuously at both ends. As a high-tensile steel plate, the tensile strength is 50 kgf / mm²The above is preferable, and most preferably 100 kgf / mm when considering the strength and the processing restriction (crack).²160 kgf / mm or more²It is in the following range. The thickness T is about 1.0 mm to 2.2 mm, preferably about 1.2 to 1.6 mm, and the diameter D is about 25 to 40 mm, preferably about 30 to 35 mm.
[0029]
The terminal portion 3 is gradually thinner as the thickness TV of the wall goes to the tip, and the width in the major axis direction gradually increases from the diameter D of the central portion 2 toward the tip, and the width in the minor axis direction is the tip. And a fan-shaped portion 4 having an elliptical cross-section that gradually decreases toward the end, and a thickness t (typically 0.6 mm) of the door inner panel 13 which is thinner at the tip of the fan-shaped portion 4 than T. (Thickness of about 1.0 mm), the two thin walls formed to have the same thickness T1 are superimposed on each other to form a double-walled plate-shaped portion 5 having a maximum width W of the fan-shaped portion 4. And Further, the width W is formed so as to exceed πD あ る 2 which is the width when the round pipe is crushed.
[0030]
In this embodiment, the overlapping surface 6 of the two walls of the plate portion 5 is displaced in the radial direction from the center of the central portion 2 to form the plate portion 5 linearly aligned with one side of the central portion 2. The overlapping walls are fixed to each other at a plurality of places so as not to be separated by spot welding 7.
[0031]
A plurality of cutouts 8 are formed on one wall of the plate-shaped portion 5 so as to be shifted from the spot weld 7 in the width W direction, and the other wall corresponding to these cutouts 8 is a door. The portion 9 is to be attached to the inner panel 13.
[0032]
At the substantially center of the plate-shaped portion 5 in the width W direction, a suture line 10 of the pipe is arranged, and when the door beam 1 is attached to the door inner panel 13, an unillustrated door provided on the door inner panel 13 is provided. A positioning hole 11 for positioning that engages with the projection is formed.
[0033]
In this embodiment, as shown in FIGS. 4 and 5, the door beam 1 has the inclined surface of the terminal portion 3 directed toward the door outer panel 14, and the other flat surface of the terminal portion 3 faces the door inner panel 13. The stepped portion 16 formed inside along the peripheral edge of the door outer panel 14 that is fastened and fastened to the door outer panel 14 overlaps, and the portion 9 to be mounted is spot-welded 17 to the stepped portion 16. In some cases, a separate reinforcing plate (not shown) is welded to the step portion 16. In this case, spot welding 17 including the reinforcing plate is performed.
[0034]
At the time of spot welding, when the door inner panel 13 and the mounting scheduled portion 9 are overlapped and the planned mounting portion 9 is welded with spot electrodes sandwiched therebetween, two plates are welded. Welding is easier and more stable than spot welding with overlapping plates.
[0035]
A door window panel (not shown), a window regulator for raising and lowering the door window panel, and the like are stored between the bulging portion 18 protruding from the step portion 16 of the door inner panel 13 toward the vehicle interior and the door beam 1.
[0036]
According to the structure of this embodiment, when the door outer panel 14 is deformed toward the cabin and the door beam 1 receives a collision load at the time of a side collision of the vehicle, the door beam 1 is opposed to the cabin of the door 12 by the collision load. It is possible to improve the occupant protection performance by suppressing the amount of inward deformation small.
[0037]
In particular, according to this embodiment, the terminal portion 3 of the door beam 1 passes through the fan-shaped portion 4 having an elliptical cross section which gradually becomes thinner as the thickness TV of the wall goes to the tip, and has a thin wall thickness T1. Since the plate-like portion 5 having a double wall structure in which the walls are superimposed is integrally formed continuously, when the terminal portion 3 is integrally formed with the central portion 2, cracks or the like are not generated due to internal stress. Thus, the strength and rigidity of the door beam 1 can be increased.
[0038]
The plate portion 5 has a cutout 8 formed on one wall of the double wall structure, and a portion of the other wall corresponding to the cutout 8 is formed as a portion 9 to be attached to the door inner panel 13. Since the portion 9 to be attached is spot-welded 17 to the door inner panel 13 even when the thickness of the double-walled structure exceeds twice the thickness t of the door inner panel 13, The portion 9 is formed to be substantially thinner than the thickness of the central portion, so that the door beam 1 can be appropriately joined to the door inner panel 13.
[0039]
Further, since the thickness T1 of the scheduled mounting portion 9 is formed to be substantially the same as the thickness t of the door inner panel 13, an appropriate welding nugget can be formed without melting the door inner panel 13 and high joining. It is possible to join with high strength, improve the quality stability, and easily perform joining work and welding work management. The thickness t of the door inner panel 13 is the thickness of the panel itself and the case where a metal plate having a thickness of about 1.6 mm to 2.5 mm is separately welded to the step 16 of the panel as a reinforcing plate material. In this case, the thickness including the thickness of the reinforcing plate is the thickness t of the door inner panel 13. Furthermore, since the pipe suture line 10 is disposed substantially at the center of the plate-shaped portion 5 in the width W direction, a crack is less likely to be formed from the suture line 10 at the time of a side collision of the vehicle, and the rigidity of the door beam 1 is further improved. can do.
[0040]
Further, the plate-like portion 5 is formed by disposing the overlapping surface 6 of the two walls in the radial direction from the center of the central portion 2 so that the plate-like portion 5 is linearly aligned with one side of the central portion 2. Therefore, the entire area of the terminal portion 3 can be joined to the step 16 of the door inner panel 13, and the joining strength of the door beam 1 can be increased.
[0041]
As a result, according to this embodiment, as shown in FIGS. 6 and 7, even when the side impact load F acts and the central portion 2 is deformed toward the vehicle interior, the plate-like shape is obtained. Since the overlapping walls of the portion 5 are connected to each other and the plate portion 5 is firmly connected to the step portion 16 of the door inner panel 15, the joining portion between the plate portion 5 and the step portion 16 is formed. The plate-shaped portion 5 does not peel off from the step portion 16 by receiving a tensile load acting as indicated by an arrow a in the shear direction advantageous in strength, and the collision load received in the central portion 2 is applied to the terminal portion 3. Therefore, the amount of deformation of the door 12 toward the vehicle interior can be minimized.
[0042]
Next, a method of manufacturing the door beam 1 will be described with reference to FIGS.
[0043]
First, the end of the ERW pipe 20 made of a high-tensile steel plate having a diameter D and a thickness T shown in FIG. 8 is formed into a substantially trumpet-like shape as shown in FIG. 9 by using a spinning method (commonly referred to as “spatial drawing”). Plastic working.
[0044]
In order to perform this plastic working, the split type chuck 21 is opened, and after inserting the end of the pipe 20 into the chuck 21, the chuck 21 is closed and the pipe 20 is held.
[0045]
When the chuck 21 is closed, a substantially truncated conical receiving surface 21a and a circular receiving surface 21b corresponding to a press die are formed inside the end of the chuck 21. There is a gap between the receiving surfaces 21a and 21b and the outer peripheral surface of the end of the pipe 20 indicated by a virtual line in FIG.
[0046]
A pressing device 24 having a core rod 22 and a pressing tool 23 at the distal end thereof is inserted into the pipe 20 from the end, and the pressing tool 23 is placed near the connecting portion of the truncated conical receiving surface 21a with the pipe holding portion 21c. And a part of the outer peripheral surface of the pressing tool 23 is brought into contact with a part of the inner peripheral surface of the pipe 20, and the pipe 20 is rotated together with the chuck 21 in the circumferential direction.
[0047]
While the rotation of the pipe 20 is continued, the pressing device 24 is moved from the contact position P to the side opposite to the insertion direction while the pressing tool 23 is strongly pressed against the inner surface of the pipe 20, and the pressing tool 23 is moved to the position shown in FIG. By repeatedly moving the pressing tool 23 from the contact position P on the inner surface of the pipe 20 until the movement locus indicated by the arrow X is drawn, the terminal portion 25 of the pipe 20 is moved outward in the radial direction. The thickness of the end portion 25 of the pipe 20 increases with the progress of the expansion, and the thickness T of the central portion 26 of the pipe 20 held by the pipe holding portion 21c of the chuck 21 increases. From the direction toward the pressing movement direction of the pressing tool 23.
[0048]
In the process of repeating the movement of the pressing tool 23 from the contact position P on the inner surface of the pipe 20, the pressing force and the moving speed of the pressing tool 23 are adjusted to adjust the expanded terminal portion 25 of the pipe 20. The outer peripheral surface contacts the frusto-conical receiving surface 21a and the circular receiving surface 21b of the chuck 21, and the thickness TV of the portion 27 of the pipe 20 corresponding to the frusto-conical receiving surface 21a is the thickness of the central portion 26. The thickness T1 of the portion 28 of the pipe 20 corresponding to the circular receiving surface 21b and the thickness T1 of the pipe 28 corresponding to the circular receiving surface 21b became the thinnest of the above-mentioned thickness TV in the entire region, while being gradually thinned from T toward the distal end side. It is formed so as to have the same thickness as the thickness.
[0049]
When the end portion 25 of the pipe 20 cannot be expanded into a trumpet shape having a desired size by the spinning process using the chuck 21 and the pressing device 24, the chuck 21 has another receiving surface having a larger receiving surface. The spinning process is repeated by replacing the chuck with a split type chuck (not shown). Note that the final diameter of the terminal portion 25 is determined by the size required for the mounting plate portion of the door beam, and when a pipe having a diameter of about D = 50 mm is used, the diameter of this portion is 2 to 2. Expanding in 3D is practically preferred.
[0050]
In FIG. 9, the process of plastically processing one end portion 25 of the pipe 20 into a substantially trumpet shape has been illustrated and described. However, the other end portion of the pipe 20 may be simultaneously processed or the plasticity of the one end portion 25 may be plastically processed. When the processing is completed, the other end may be processed using the chuck 21 shown in FIG.
[0051]
After the plastic working, the pipe 20 is removed from the chuck 21, and a notch as shown in FIGS.
[0052]
In order to carry out this notch processing, a punch 29 constituting the male mold of the press shown in FIGS. 10 and 11 is radially inserted from a receiving portion 31 which projects cylindrically from one end surface of a die 30 constituting the female mold of the press. In a state of being separated outward, the circular portion 28 of the end portion 25 formed in a trumpet shape of the pipe 20 is circumscribed to the receiving portion 31 and abuts on the end surface 32 of the die 30.
[0053]
In this embodiment, three notches 36 (see FIG. 12) are formed in the circular portion 28 of the pipe 20 within a range not exceeding half in the circumferential direction. As shown in FIG. 5, three processing holes 33 are provided, and a punch 29 is arranged coaxially with these processing holes 33.
[0054]
Further, when the circular portion 28 of the pipe 20 is mounted on the receiving portion 31, the suture line 34 of the pipe 20 is arranged coaxially with the processing hole 33 located at the center.
[0055]
The punch 29 moves along the end face 33 of the die 30 toward the center of the receiving portion 31 so that the punch 29 cuts the edge of the circular portion 28 of the pipe 20 in cooperation with the processing hole 33. And cut it out.
[0056]
The cutting member (not shown) generated at the time of this processing is pushed out into the processing hole 33 by the tip of the punch 29 and falls into the discharge hole 35 connected to the processing hole 33.
[0057]
Thereafter, the punch 29 is moved backward in the direction opposite to the moving direction at the time of the notch processing to return to the original position as shown in FIG.
[0058]
Due to this notch processing, a plurality of notches 36 having a bottom edge of a substantially semi-arc shape are formed in the circular portion 28 of the end portion 25 of the pipe 20 as shown in FIG. The substantially semi-circular notch 36 is useful because it can prevent stress concentration during use as a door beam.
[0059]
Then, the pipe 20 is removed from the die 30, and the end portion 25 of the pipe 20 is plastically worked so that its cross-sectional shape becomes an elliptical shape.
[0060]
To perform this plastic working, as shown in FIG. 13, a pair of spreaders 37 are arranged in a direction perpendicular to the center notch 36 and inserted into the end portion of the pipe 20, and a pair of spreaders 37 are formed. Are moved in opposite directions to each other, each expanding device 37 pushes the left and right portions of the terminal portion 25 outward, respectively, and applies a compressive force P from above and below. The upper and lower portions 25 move in a direction approaching each other, whereby the terminal portion 25 is plastically deformed from a circular shape shown by a solid line to an ellipse or an elliptical shape shown by a virtual line.
[0061]
Subsequently, after removing the pair of spreaders 37 from the inside of the terminal portion 25 having an oval shape, as shown in FIG. Pressing is performed to form a plate-shaped portion 38 having a width W where the opposing walls overlap each other.
[0062]
As a result, the end portion 25 composed of the fan-shaped portion 40 and the plate-shaped portion 38, each of which has a substantially elliptical cross section, is continuously and integrally formed at both ends of the central portion 26.
[0063]
In this embodiment, as shown in FIG. 14, the suture line 34 of the pipe 20 is positioned substantially at the center of the plate-shaped portion 38 in the width W direction, and the outer surface of one wall of the plate-shaped portion 38 has a circular shape. The outer wall of the central portion 26 having a shape is extended substantially linearly, and the other wall having the cutout portion 36 on one wall is overlapped, so that the overlapping surface 41 of the wall extends radially from the center of the central portion 26. And at both edges in the width W direction, one wall and the other wall form a circular internal gap 42 in order to more reliably prevent cracking during press working. An arc-shaped bead 43 having a small curvature is formed.
[0064]
In the plate-like portion 38, the overlapping walls are fixed to each other by spot welding 44 on both sides of each notch 36, and by locating holes (not shown) in portions other than the notch 36 and spot welding 44, A door beam 1 as shown in FIG. 1 can be obtained.
[0065]
In short, according to the method of this embodiment, the step of plastically processing the end of the pipe 20 into a substantially trumpet shape, the step of cutting out the edge of the trumpet-shaped portion, the plastic processing of the trumpet-shaped portion into an oval shape And a step of superimposing the tip of the elliptical portion, using a pipe 20 made of a high-tensile steel plate cut into a predetermined length L having a diameter D and a wall thickness T having a circular cross section, Since the end portion 25 composed of the fan-shaped portion 40 and the plate-shaped portion 38 each having an oval cross section can be integrally formed with the door beam 26, the door beam 1 having high strength and rigidity as shown in FIG. It can be easily manufactured.
[0066]
In particular, in the trumpet-shaped plastic working step, the pressing tool 23 is pressed against the inner surface of the pipe 20 while rotating the pipe 20 in the circumferential direction to apply a pressing force in the radial direction, and the pressing tool 23 is moved relatively to the pipe 20. By using a spinning process for moving the pipe 20 toward the outside in the axial direction, the pressing force and the moving speed of the pressing tool 23 are adjusted, and the terminal portion 25 of the pipe 20 is expanded and thinned without generating a crack or the like. Can be performed.
[0067]
In the manufacturing method of this embodiment, the steps of plastically processing the trumpet-shaped part into an oval shape and the step of superimposing the tip of the oval-shaped part are described as being performed separately, but these steps must be performed simultaneously. Needless to say, the notch process shown in FIGS. 10 and 11 was performed before the oval plastic working shown in FIG. The end portion of the pipe having an oval cross-section is circumscribed by fitting the end portion of the pipe having an oval cross-section to a receiving portion having an oval cross-section of a die (not shown). Since the die is positioned so as not to rotate, the notch can be machined with a precise circumferential position.
[0068]
Further, at the time of spinning, the thickness of the plate-shaped portion 38 formed as a thickness T1 at a portion corresponding to the circular receiving surface 21b shown in FIG. 9 and having a double wall structure as shown in FIG. If the thickness is substantially the same as the thickness t of the door inner panel 18 to which the door beam 1 shown in FIG. 5 is attached, it is not necessary to form the notch 36 shown in FIG. , An elliptical plastic working step and a polymerization step.
[0069]
In addition, the terminal portion 25 of the pipe 20 is subjected to an annealing treatment as a pre-process of the trumpet-shaped plastic working process to reduce the hardness of the terminal portion 25 or to heat the terminal portion 25 of the pipe 20 in the trumpet-shaped plastic working process. By reducing the hardness of the terminal portion 25, the terminal portion 25 can be more smoothly expanded and thinned.
[0070]
Also, as shown in FIG. 14, the overlapping surface 41 of the plate-shaped portion 38 is shifted in the radial direction from the center of the central portion 26, but in the embodiment shown in FIG. It is formed so as to substantially coincide with the center of the central portion 26.
[0071]
According to this embodiment, it is possible to easily perform the press working for stacking the plate-shaped portions 38 as compared with the case where the overlapping surface 41 of the plate-shaped portions 38 is displaced in the radial direction from the center of the central portion 26. Not only can this be achieved, but also the amount of protrusion toward the outer panel with respect to the plate-shaped portion 38 can be reduced to の of the diameter of the central portion 26.
[0072]
Further, as shown in FIG. 12, the notch portion 36 is formed to have a small width in the circumferential direction. However, in the embodiment shown in FIG. 16, the notch portion 45 is formed to have a wide width in the circumferential direction and not to form sharp corners. The corner 46 of the notch 45 is formed in an arc shape.
[0073]
According to this embodiment, notch processing and equipment can be simplified, and attachment work by welding or the like to a vehicle body panel and management (strict positional accuracy of a welded portion can be eased) can be facilitated.
[0074]
【The invention's effect】
As described above, according to the present invention, the following effects can be obtained.
[0075]
According to the first aspect, the mounting end portions at both ends of the central portion are formed in a wide plate-like portion having a double wall structure that overlaps through a fan-shaped portion having a cross section of an elliptical shape. The strength and rigidity of the door beam can be increased without causing cracks or the like due to excessive internal stress in the terminal portion, and the mounting strength to the vehicle body panel can be improved.In addition, by fixing the portion to be mounted remaining in the cutout portion to the door panel, even if the double-walled structure is thicker than twice the thickness of the door panel, it is substantially thinner. The mounting portion can be properly joined to the door panel without melting the door panel, and the joining strength of the door beam to the door panel can be increased.
[0076]
According to the second aspect, since the two walls of the plate-like portion are fixed to each other, opening of the terminal portion can be prevented, and the strength and rigidity of the door beam can be further increased.
[0078]
Claim3According to the method, the pipe suture line is disposed substantially at the center in the width direction of the plate-shaped portion. Therefore, at the time of a side collision of the vehicle, cracks hardly enter from the suture line portion, and the rigidity of the door beam is further improved. be able to.
[0079]
Claim4According to this, since the overlapping surface of the plate-like portion is shifted in the radial direction from the center of the central portion, the entire area of the terminal portion is attached to the door panel by being overlapped, and the mounting strength can be further improved.
[0080]
Claim5According to the method described above, the overlapped surface of the plate-shaped portion is made substantially coincident with the center of the central portion, so that the formability can be improved and the amount of protrusion to the outer panel side with respect to the plate-shaped portion can be reduced. It can also be used suitably for vehicles with little clearance with the panel.
[0081]
Claim6According to the above, the end portion consisting of a fan-shaped portion and a plate-shaped portion having an oblong cross section at both ends of the central portion can be integrally formed without generating excessive internal stress, and a door beam having high strength and rigidity Can be easily obtained.
[0082]
Claim7According to this, a door beam having a high joining strength with the door panel can be obtained by the notch processing.
[0083]
Claim8According to the method, since the spinning process is used for the trumpet-shaped plastic working, the terminal portion can be expanded and thinned without cracks or the like.
[0084]
Claim9According to the method, the hardness of the terminal portion is reduced by performing an annealing process as a pre-process of the trumpet-shaped plastic working, so that the terminal portion can be easily expanded and thinned with a small force.
[0085]
Claim10According to the method, since the hardness of the terminal portion is reduced by heating during the trumpet-shaped plastic working, the terminal portion can be expanded and thinned with a small force without difficulty.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an appearance of a door beam according to a first embodiment of the present invention.
FIG. 2 is a plan view of the embodiment.
FIG. 3 is a sectional view taken along line AA of FIG. 2;
FIG. 4 is a perspective view of a vehicle door to which the door beam of the embodiment is attached.
FIG. 5 is a sectional view taken along line BB of FIG. 4;
FIG. 6 is an operation explanatory view of the embodiment.
FIG. 7 is an operation explanatory view in which main parts of the embodiment are enlarged.
FIG. 8 is a sectional view showing a pipe used in the method of the present invention.
FIG. 9 is a cross-sectional view showing a trumpet-shaped plastic working in the method of the present invention.
FIG. 10 is a sectional view taken along line CC of FIG. 11;
FIG. 11 is a partially broken side view showing the notch processing of the method of the present invention.
FIG. 12 is a perspective view showing a part of the intermediate product after the notch processing.
FIG. 13 is an end view showing an oval plastic working of the method of the present invention.
FIG. 14 is an end view showing a product after polymerization processing by the same method.
FIG. 15 is an end view showing a product after polymerization processing according to different methods of the present invention.
FIG. 16 is an end view showing an intermediate product after notching by a different method of the present invention.
[Explanation of symbols]
1 door beam
2 Central part
3 Terminal part
4 Fan-shaped part
5 plate part
6 Polymerized surface
7 spot welding
8 Notch
9 Scheduled mounting part
10 Suture line
13 Door inner panel
14 Door outer panel
15 Internal space
20 pipes
23 Press tool
25 Terminal part
26 Central part
27 frustoconical part
28 circular part
34 Suture Line
36 Notch
38 Plate
40 fan-shaped part
41 Polymerized surface
42 Internal clearance
43 Bead
44 spot welding
45 Notch

Claims (10)

A door beam made of a pipe made of high-tensile steel plate attached in the front-rear direction to an internal space between an outer panel and an inner panel on a side portion of a vehicle, the beam comprising a central portion forming a beam main body, and a longitudinal portion of the central portion. A terminal part for attachment molded integrally with the direction terminal, and the terminal part has a wall whose thickness becomes gradually thinner toward the front end from the central part, and a long diameter direction width is larger than that of the central part. Also has a fan-shaped section with an elliptical cross section whose width in the minor diameter direction gradually decreases toward the tip from the center, while gradually expanding toward the tip, and two thin walls at the tip of this fan-shaped part. It is constituted by a plate-shaped portion formed to have the maximum width of the fan-shaped portion by being overlapped with each other , and this plate-shaped portion has a cutout in a part of one wall, and the other corresponding to the cutout. Form the wall part as the part to be attached to the body panel Door beam for a vehicle, characterized in that. 2. The door beam for a vehicle according to claim 1, wherein the two walls of the plate portion are fixed to each other. Pipe consists electric-resistance-welded pipe, vehicular door beam according to claim 1 or 2, characterized in that a the suture approximately in the center in the width direction of the terminal portion. The vehicle door beam according to any one of claims 1 to 3 , wherein the overlapping surfaces of the two walls of the plate-shaped portion are shifted in position in the radial direction from the center of the central portion. The vehicle door beam according to any one of claims 1 to 3 , wherein the overlapping surfaces of the two walls of the plate-shaped portion are made to substantially coincide with the center of the central portion. A step of expanding the end portion of the high-strength steel pipe outward in the radial direction and plastically processing the pipe into a substantially trumpet shape in which the wall thickness gradually decreases, and plastically forming the trumpet-shaped portion into an elliptical cross section. And a step of overlapping walls which are opposed to each other at the narrower edge at the edge of the oval-shaped portion. A step of expanding the end portion of the high-strength steel pipe outward in the axial direction and plastically processing the pipe into a substantially trumpet shape in which the wall thickness gradually decreases, and half of the annular edge of the trumpet portion in the circumferential direction. Notching within a range not exceeding, a step of plastically processing the trumpet-shaped portion so as to have an elliptical cross section, and a step of overlapping walls which are opposed to each other at a narrower edge at an edge of the elliptical portion. A method for manufacturing a door beam for a vehicle, comprising: In the process of plastic working into a trumpet shape, a pressing tool is pressed against the inner surface of the end of the pipe while rotating the pipe in the circumferential direction to apply a pressing force in the radial direction, and the pressing tool and the pipe are relatively moved to the pipe axis. The method of manufacturing a door beam for a vehicle according to any one of claims 6 and 7 , wherein a spinning process of moving outward in a direction is used. 9. The vehicle door beam manufacturing according to claim 6 , wherein as a step prior to the step of plastic working in a trumpet shape, the hardness of at least the plastic processed portion in the trumpet shape is reduced by annealing. Method. The method for manufacturing a door beam for a vehicle according to any one of claims 6 to 8 , wherein, when the plastic working is performed in a trumpet shape, at least a plastic processed portion in a trumpet shape is heated to reduce the hardness of the portion.

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