JP2016182921A - Beam structure member - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a beam structure member which prevents occurrence of electric corrosion etc., achieves excellent joint strength, and prevents a complicated manufacturing process.SOLUTION: A beam structure member 100 includes: a first cylindrical member 11; a first resin layer 15 which is laminated on an outer peripheral surface of the first member 11 by injection molding; and a second member 17 which is disposed overlapping with the first resin layer 15, made of a light alloy material, and has a cylindrical part. The second member 17 is fixedly swaged to the first member 11 through the first resin layer 15 by electromagnetic forming.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a beam structural member.

  Many structural members such as automobile door beams include a main body and a bracket member for attaching the main body to another member. For example, Patent Document 1 discloses a structural member in which a cylindrical member is inserted into another cylindrical member and joined using mechanical fastening means such as welding or bolts and nuts. In structural members such as automobile door beams as described above, weight reduction has been promoted from the viewpoint of reducing energy consumption. In addition to conventional steel members, high-strength steel, aluminum or aluminum alloys, magnesium alloys, etc. The lightweight metal is also adopted. From such a situation, cases where the potentials of the bracket member and the beam member are different are increasing.

  When the bracket member and the door beam are made of metals having different potential differences, galvanic corrosion is likely to occur. Therefore, it has been studied to provide an insulating layer or the like so that the two metals are not in direct contact with each other. For example, a technique for holding a member (steel bolt or the like) that fastens both of them using an insert nut whose surface is subjected to corrosion resistance treatment such as Geomet (registered trademark) has been studied (Patent Document 2). However, such a corrosion-resistant film has poor adhesion and may be peeled off when the member is attached. Therefore, there is a problem that electric corrosion cannot be sufficiently prevented.

  In addition, the use of fiber reinforced resin such as CFRP (carbon fiber reinforced plastic) as a beam material is also being studied. However, the joint portion between the bracket member and the beam member cannot be welded, and it may be necessary to join both members using an adhesive. In that case, it is difficult to uniformly control the thickness of the adhesive between the bracket member and the beam within a certain range, and the bonding strength tends to vary. As a result, there are cases where sufficient bonding strength cannot be ensured.

JP 2000-108662 A JP 2008-201377 A

  The present invention has been made in view of the above matters, and an object thereof is to provide a beam structure member that prevents the occurrence of electrolytic corrosion and the like, has excellent bonding strength, and does not complicate the manufacturing process. It is.

The beam structural member of the present invention is
A cylindrical first member;
A first resin layer laminated by injection molding on the outer peripheral surface of the first member;
A second member disposed on the first resin layer and having a cylindrical portion made of a light alloy material;
With
The second member is fixed by caulking to the first member via the first resin layer by electromagnetic molding.
Further, the first member may be formed with at least one through hole penetrating the outer peripheral surface and the inner peripheral surface, and the through hole may be filled with a resin material.
The first member may have a second resin layer laminated on the inner peripheral surface.
The second member may have a high-rigidity portion that is higher in rigidity than other portions, at least at a portion along the circumferential direction.
Each of the first member and the second member may have a rectangular tube shape, and the highly rigid portion may be a corner portion of the rectangular tube shape.
The second member may include a rib portion extending outward from the high-rigidity portion.
The first resin layer may be formed with a protruding portion that protrudes toward the highly rigid portion at a circumferential position corresponding to the highly rigid portion of the second member.

  According to the present invention, the cylindrical second member is disposed so as to overlap the cylindrical first member having the resin layer formed on the outer surface, and the first member and the second member are interposed via the first resin layer. The structure is fixed by caulking by electromagnetic forming. Thereby, the strong 1st resin layer which has the stable thickness is formed in the surface of the 1st member, and generation | occurrence | production of electrolytic corrosion etc. can be prevented reliably. Moreover, it can be set as the structure excellent in joining strength, without making a manufacturing process complicated.

It is a figure for demonstrating embodiment of this invention, and is a perspective view of the beam structure member of a 1st structural example. It is a perspective view which shows the resin layer formed in the edge part outer surface of a main-body part. It is the side view of the main-body part and resin layer seen from the V1 direction of FIG. It is the side view of the main-body part and resin layer which formed the resin layer in the outer peripheral surface and inner peripheral surface of a main-body part. (A), (B), (C) is sectional drawing which shows the various shapes of a bracket member. It is a block diagram of the electromagnetic forming apparatus used for manufacture of a beam structural member, (A) is a side view of an electromagnetic forming apparatus, (B) is a front view of the electromagnetic forming apparatus seen from the V2 direction of (A). It is typical sectional drawing which shows the position of the highly rigid part of the cylindrical part which consists of a corner | angular main-body part. It is a reference figure which shows a mode that a clearance gap produces between a cylindrical part and a resin layer. (A) Side view of a beam structure member showing a state in which a convex portion is formed at a circumferential position corresponding to a highly rigid portion of the resin layer, (B) is a side view of the beam structure member after electromagnetic forming (A). It is.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. Here, a case where the beam structural member is applied to an automobile door beam or the like will be described as an example, but the present invention is not limited thereto.
<First configuration example>
FIG. 1 is a perspective view showing an overall configuration of a beam structure member for explaining an embodiment of the present invention.
The beam structure member 100 of this configuration includes a cylindrical main body (first member) 11 and a pair of bracket members 13 and 13 attached to both ends of the main body 11, respectively. The main body 11 is formed with resin layers (first resin layers) 15 covering the outer peripheral surfaces of the end portions at both ends in the longitudinal direction.

  The bracket member 13 includes a tubular portion (second member) 17 and a rib portion 19 extending outward from the tubular portion 17. The cylindrical portion 17 is inserted into an end portion of the main body portion 11 on which the resin layer 15 is formed, and the bracket member 13 is caulked and fixed to the main body portion 11 via the resin layer 15 by electromagnetic molding described later.

  The beam structure member 100 having the above configuration is not limited to the above structure, and it is sufficient that at least one bracket member 13 is joined to the main body 11. The main body 11 is not limited to a single linear cylinder, and may have a configuration in which a plurality of cylinders are joined with one or more branch points. Furthermore, the structure by which the bracket member 13 is arrange | positioned at the front-end | tip of the branched cylinder may be sufficient. Moreover, you may arrange | position impact-absorbing components, such as an aluminum extrusion material with a rib, in the inside of the main-body part 11 as needed.

Hereinafter, each part of the beam structure member 100 having the above-described configuration will be sequentially described.
(First member)
The main body portion 11 as the first member has a straight tube structure with a circular cross section, but is not limited to a circular cross section, and the cross section may be an elliptical shape or a rectangular or polygonal cross section. Examples of the material of the main body 11 include metals such as aluminum alloy materials (JIS standard 6000 series, 5000 series, 7000 series, 2000 series, 3000 series, etc.), magnesium alloys, steel materials (soft steel, high-tensile steel), and titanium alloys. Material is used.

  In order to make the main body 11 cylindrical, an extrusion method can be used if the main body 11 is aluminum or magnesium. Moreover, if the main-body part 11 is steel materials and titanium, the method of joining the edge part of a board | plate material by resistance seam welding can be utilized.

  The main body 11 may be a non-metallic material such as carbon fiber reinforced plastic (CFRP) in addition to the metal material. Other non-metallic materials include glass fiber reinforced plastic (GFRP), long glass fiber reinforced plastic (GMT), boron fiber reinforced plastic (BFRP), aramid fiber reinforced plastic (AFRP, KFRP), polyethylene fiber reinforced plastic (DFRP). ), Zylon reinforced plastic (ZFRP), and the like. Such a fiber reinforced plastic is obtained by laminating a prepreg of resin and fiber into a tubular shape, and heating and curing the annular prepreg in an oven.

  The surface of the main body 11 on which the resin layer 15 is laminated by injection molding is preferably subjected to primer treatment. Examples of the adhesive used for the primer treatment include a low-viscosity liquid with a small non-volatile content, such as a modified polyolefin-based paint and a modified epoxy-based primer. When the primer-treated layer is formed on the surface of the main body 11, the adhesion between the main body 11 and the resin layer 15 is improved.

  A silane coupling agent or a hydrolyzate thereof may be separately added to the primer treatment layer. Thereby, the adhesiveness of the main-body part 11 and the resin layer 51 through a primer process layer becomes stronger. As a specific example of the primer treatment, when the main body 11 is an aluminum alloy material, for example, Mitsui Chemicals Unistall R-300 (registered trademark) is preferably used. In the case where the main body 11 is a steel material, for example, Daicel Evonik Vestamelt (registered trademark) is preferably used. In the case of an aluminum alloy or steel material, non-chromate chemical conversion treatment such as phosphoric acid chromate or Ti-Zr may be performed as a base treatment before the primer treatment.

(Resin layer)
The resin layer 15 is formed on the primer treatment layer of the main body 11 by injection molding a molten resin. Here, the resin material which comprises the resin layer 15 will not be specifically limited if it is a resin composition used for normal injection molding. Examples of the resin material used for the resin layer 15 include thermoplastic resins such as polypropylene, polyamide, polyethylene, polystyrene, ABS resin, vinyl chloride resin, and fluororesin.

  The resin material may contain fillers such as talc, metal fibers, glass fibers, and various additives. In that case, the filling rate of the filler into the resin material is to improve the strength of the resin material while ensuring the fluidity of the resin material at the time of injection molding. In the case of talc: about 5 to 40%, in the case of metal fiber : About 5 to 20%, In the case of glass fiber: It is preferable to set it as 5 to 65%.

  2 is a perspective view showing a resin layer (first resin layer) 15 laminated on the outer surface of the end portion of the main body 11, and FIG. 3 is a side view of the main body 11 and the resin layer 15 as viewed from the direction V1 in FIG. It is. Although it is essential to laminate the resin material on the outer peripheral surface 11a of the main body part 11, as shown in FIG. 4, a resin layer (second resin layer) 16 is also laminated on the inner peripheral surface 11b of the main body part 11. May be. By laminating the resin layers 15 and 16 on both the outer peripheral surface 11a and the inner peripheral surface 11b, the corrosion resistance of the main body 11 can be further enhanced and the rigidity as a component can be improved.

  In addition, the both ends of the main-body part 11 may be formed with the through-hole 21 which penetrates the outer peripheral surface 11a and the inner peripheral surface 11b. By filling the through hole 21 with the resin material, the bonding strength between the resin material and the main body 11 can be further increased. The resin material to be filled is preferably the same resin material as the resin layers 15 and 16, and in this case, the resin layers 15 and 16 can be simultaneously molded by injection molding.

  The lamination thickness of the resin layer 15 is preferably about 1.5 to 3 mm at the thinnest point in terms of injection moldability. In addition, the resin layer 15 can be provided with protrusions, fins, reinforcing ribs, and the like that protrude in the outer peripheral direction as necessary. By providing such a protrusion or the like, the effect of stopping the bracket member 13 to be described later is improved.

(Second member)
The cylindrical portion 17 of the bracket member 13 that is the second member has a cross-sectional shape similar to the cross-sectional shape of the main body portion 11. That is, when the main body portion 11 has a circular cross section, the cylindrical portion 17 has a round tube shape, and when the main body portion 11 has a rectangular tube shape, the cylindrical portion 17 has a rectangular tube shape.

  5A, 5 </ b> B, and 5 </ b> C are cross-sectional views illustrating various shapes of the bracket member 13. As shown in FIG. 5A, which is a cross-sectional view taken along line AA of FIG. 1, the cylindrical portion 17 of the bracket member 13 includes rib portions 19 for fastening bolts and nuts for attachment to other parts and the like. 19 The rib portions 19 and 19 are formed in a flat shape as in the illustrated example, and the shape can be appropriately changed according to the shape of another structural member to be attached.

  For example, as shown in FIG. 5B, the shape of a pair of rib portions 19A and 19A that are parallel to each other may be employed. Further, as shown in FIG. 5C, when the cylindrical portion 17A having a rectangular cross section is used instead of the cylindrical portion 17 having a circular cross section, the shape of the flat rib portions 19B and 19B, It can be shaped.

  The cylindrical portions 17 and 17A move in the caulking direction by the Lorentz force due to the induced current during electromagnetic forming. Therefore, the cylindrical part 17 needs to be comprised with highly conductive light alloy materials, such as aluminum or aluminum alloy, and a magnesium alloy.

<Production method of beam structural member>
Next, a procedure for manufacturing the beam structure member 100 having this configuration will be described.
Schematically, the resin layer 15 is formed on both ends of the main body 11 by a known injection molding method. And the cylindrical part 17 of the bracket member 13 is respectively crimped and fixed to the part by which the resin layer 15 of the main-body part 11 was shape | molded with the electromagnetic shaping | molding apparatus. Thereby, the beam structural member 100 is completed.

The process of performing caulking and fixing using the electromagnetic forming apparatus will be described in detail below.
6A and 6B are configuration diagrams of an electromagnetic forming apparatus 31 used for manufacturing the beam structural member 100 having this configuration. FIG. 6A is a side view of the electromagnetic forming apparatus, and FIG. 6B is an electromagnetic forming apparatus viewed from the V2 direction in FIG. FIG.

  The electromagnetic forming apparatus 31 includes a conductor coil 31A arranged in a spiral shape and a pair of upper and lower magnetic flux concentrators 31B and 31C in the drawing. The magnetic flux concentrators 31B and 31C are respectively disposed on the inner diameter portion of the conductor coil 31A. A small-diameter portion 33 that protrudes toward the center of the inner diameter portion is formed at one end in the longitudinal direction of the magnetic flux concentrators 31B and 13C. The small diameter portion 33 has a function of concentrating the magnetic flux generated by the conductor coil 31 </ b> A toward the inner peripheral surface of the small diameter portion 33.

  One end in the longitudinal direction of the magnetic flux concentrators 31 </ b> B and 31 </ b> C defines a cavity 35 along the shape of the cylindrical portion 17. When the cylindrical portion 17 has the rib portion 19, the cavity 35 is shaped to surround the entire cylindrical portion 17 and the rib portions 19 and 19. The electromagnetic forming device 31 accommodates the end of the beam structural member 100 in the cavity 35 and performs processing.

  Next, a processing procedure will be described. First, the main body 11 having been subjected to resin injection molding is inserted into the tubular portion 17 of the bracket member 13.

  Then, as shown in FIGS. 6A and 6B, the bracket member 13 in which the main body portion 11 is inserted into the cylindrical portion 17 is inserted into the cavity 35 of the electromagnetic forming device 31. Thereby, the circumference | surroundings of the bracket member 13 are surrounded by the magnetic flux concentrators 31B and 31C.

  In this state, the inner peripheral surface of each small diameter portion 33 of the magnetic flux concentrators 31 </ b> B and 31 </ b> C is disposed in the vicinity of the outer peripheral surface of the cylindrical portion 17 and surrounds the outer peripheral surface of the cylindrical portion 17.

  The drive circuit for the conductor coil 31 </ b> A includes a power source 37, a capacitor 39, a charge switch 41, and a discharge switch 43. When the discharge switch 43 is opened and the charge switch 41 is closed, the capacitor 39 is charged by receiving power from the power source 37. When the charging switch 41 is opened after the charging and the discharging switch 43 is closed, the capacitor 39 is discharged, and a large current flows instantaneously to the conductor coil 31A. Thereby, magnetic flux is generated from the conductor coil 31A.

  The magnetic flux generated from the conductor coil 31A is concentrated on the outer peripheral surface of the cylindrical portion 17 via the small diameter portion 33 of the magnetic flux concentrators 31B and 31C. As a result, an induced current is generated in the cylindrical portion 17 made of a light alloy material. Due to the interaction between the induced current and the electromagnetic field, a force (electromagnetic force) for contraction acts on the overlapping portion of the main body portion 11 and the cylindrical portion 17. The main body part 11 and the cylindrical part 17 are firmly caulked and fixed by this contraction action.

  By the electromagnetic molding, the caulking and fixing between the resin layer 15 of the main body 11 and the cylindrical portion 17 can be completed in a short time. In addition, since electromagnetic forming does not generate heat as in joining by welding, an extra process such as correction of thermal strain after joining the members does not occur. Further, since the welding heat is not propagated to the surrounding members, the resin layer 15 is not damaged by heat and the insulating effect is not lowered.

  According to the beam structural member 100 manufactured as described above, when the bracket member 13 is caulked and fixed to the main body 11, the mutual members are sandwiched between the resin layers 15 having a sufficient laminated thickness. Moreover, since the resin layer 15 is laminated | stacked on the outer peripheral surface of the main-body part 11 by injection molding, lamination | stacking thickness can be made uniform with high precision. For this reason, reliable insulation is maintained and generation | occurrence | production of electrolytic corrosion etc. can be prevented reliably. Further, since the bracket member 13 and the main body portion 11 are joined via the resin layer 15, the circumferential joint strength distribution becomes uniform, and the durability of the beam structure member 100 can be improved. Furthermore, since the manufacturing process is not complicated, such as a process for controlling the coating thickness of the adhesive and a process for avoiding the influence of thermal distortion due to welding, etc., the manufacturing cost can be reduced. Further, by using the bracket member 13 made of a light alloy material, the beam structure member 100 can be reduced in weight.

<Second configuration example>
Next, a second configuration example of the beam structure member will be described. In the following description, the same members as those described above are denoted by the same reference numerals, and the description thereof is simplified or omitted.

  In the beam structural member 100 described above, the rigidity of the root portion of the rib portion 19 of the cylindrical portion 17 is high. Therefore, the amount of diameter reduction at the time of electromagnetic forming in the root portion may be smaller than other parts.

  For example, the base portions of the rib portions 19, 19A, and 19B shown in FIGS. 5A, 5B, and 5C are thicker than the other portions and become a highly rigid portion HR having high rigidity. In addition, in the rectangular tube-shaped cylindrical portion 17B shown in FIG. 7, the four corner portions of the rectangular tube shape are the high-rigidity portions HR. As described above, when the high-rigidity portion HR is provided at least at a part along the circumferential direction, the cylindrical portions 17, 17A, and 17B can be caulked and fixed in a state of being non-uniformly contracted in the circumferential direction. There is sex.

  Such a portion of the high-rigidity portion HR is caulked in a state where the amount of movement due to the reduced diameter is smaller than that of the other portions. Therefore, as shown in the reference diagram of FIG. 8, the cylindrical portion 17 is reduced in diameter, and the gaps 44 and 44 are easily generated between the cylindrical portion 17 and the resin layer 15. The gaps 44, 44 reduce the bonding strength between the main body portion 11 and the cylindrical portion 17, and the bracket member 13 rotates in the circumferential direction of the main body portion 11 when a load in the rotation direction is applied to the bracket member 13. To help you.

  Therefore, as shown in FIG. 9 (A), the resin layer 15 has convex portions 45 that protrude from the resin toward the high-rigidity portion HR at the circumferential position corresponding to the high-rigidity portion HR of the cylindrical portion 17A. 45 is provided. Since the resin layer 15 has the convex portions 45, 45, the thickness of the resin layer 15 at the circumferential position of the high-rigidity portion HR becomes larger than that of other regions.

  Therefore, as shown in FIG. 9B, after the electromagnetic forming, the cylindrical portion 17A is reduced in diameter, and a depression is generated in the highly rigid portion HR of the cylindrical portion 17A. Resin is supplied to the depressions by previously formed convex portions 45, 45 of the resin layer 15. Therefore, the gaps 44 and 44 as shown in FIG. 8 do not occur.

  Moreover, the convex parts 45 and 45 may make the axial direction both ends of the resin layer 15 thicker than another site | part. By partially thickening the resin layer 15, it is possible to prevent the bracket member 13 from coming off in the axial direction.

  8 and 9A and 9B exaggerate the size of the gap 44 and the convex portion 45 so that the present configuration and the effects can be easily understood. The size of the portion 45 is different.

  According to the beam structure member 200 of this configuration, the same effect as described above can be obtained, and the gap 44 is not generated between the tubular portion 17 and the resin layer 15 due to the reduced diameter at the time of electromagnetic forming, and the bracket member 13 The effect of stopping around the main body 11 can be enhanced.

  As described above, the present invention is not limited to the above-described embodiments, and those skilled in the art can change or apply them based on combinations of the configurations of the embodiments, descriptions in the specification, and well-known techniques. Is also within the scope of the present invention, which is intended to be protected.

11 Main body (first member)
13 Bracket member 15 1st resin layer 16 2nd resin layer 17 Cylindrical part (2nd member)
21 Through-hole 45 Convex part 100,200 Beam structure member HR High rigidity part

Claims (7)

A cylindrical first member;
A first resin layer laminated by injection molding on the outer peripheral surface of the first member;
A second member disposed on the first resin layer and having a cylindrical portion made of a light alloy material;
With
The beam structure member, wherein the second member is caulked and fixed to the first member via the first resin layer by electromagnetic molding.   2. The beam structure member according to claim 1, wherein the first member is formed with at least one through hole penetrating an outer peripheral surface and an inner peripheral surface, and the through hole is filled with a resin material.   The beam structure member according to claim 2, wherein the first member has a second resin layer laminated on an inner peripheral surface thereof.   The beam according to any one of claims 1 to 3, wherein the second member has a high-rigidity portion having rigidity higher than that of other portions at least in a part along the circumferential direction. Structural member.   The beam structure member according to claim 4, wherein each of the first member and the second member has a rectangular tube shape, and the high-rigidity portion is a corner portion of the rectangular tube shape.   6. The beam structure member according to claim 4, wherein the second member includes a rib portion extending outward from the high-rigidity portion.   7. The first resin layer is formed with a protrusion protruding toward the high-rigidity portion at a circumferential position corresponding to the high-rigidity portion of the second member. A beam structure member as described in 1.

Images