JP2013213552A - Structure and method for mounting dissimilar metal members - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a mounting structure of dissimilar metal members, capable of simplifying a member structure and streamline assembly work while preventing electric corrosion in mounting dissimilar metal members, and to provide a mounting method of the same.SOLUTION: In a mounting structure of dissimilar metal members in which a steel bush 12 of a mounting part 8c of a suspension damper 8 is fitted to a shaft member 11 arranged in an aluminum alloy wheel pipe member 4 via an annular washer 21, and the wheel hub member 4 and the mounting part 8c the suspension damper 8 are fastened by a fastening bolt 14, an insulation plate 22 mounted on the washer 21 and interposed between the washer 21 and the wheel hub member 4 is arranged, the insulating plate 22 has engaging pawls 22b engaging with the washer, an opening part 22c through which the shaft member 11 can pass, and abutting pawls 22d elastically contacting the shaft member 11 and regulating the movement of the washer 21 to the shaft member 11 when the shaft member 11 is passed through the opening part 22c.

Description

  In the present invention, a cylindrical portion of a second member made of a high-potential iron-based material is fitted into a shaft member provided on a first member made of a low-potential light metal material via an annular washer. The present invention relates to a mounting structure for dissimilar metal members fastened with bolts and a mounting method thereof.

Conventionally, in the field of automobiles, aluminum alloys mainly made of aluminum, which has excellent corrosion resistance and can be reduced in weight, have been used for many parts. On the other hand, iron-based materials mainly composed of iron are excellent in mechanical strength, rigidity, and impact resistance, and are often used for the frame of a vehicle body, a support portion, and the like.
Therefore, there are many attachment structures in which an aluminum alloy member is joined to a vehicle body side member made of an iron-based material via a bolt, so-called dissimilar metal joining structures.

  Since each metal has a unique potential, it is known that when different types of metal materials are electrically contacted in a corrosive environment, galvanic corrosion (electric corrosion) occurs according to the potential difference. This galvanic corrosion corresponds to an anode (asode) in which a low-potential metal (for example, aluminum) having a high ionization tendency when an alien metal contacts, and a high-potential metal (for example, steel) having a low ionization tendency. ) Constitutes a corrosion battery (a heterogeneous electrode battery) corresponding to a cathode (cathode) that performs a reduction reaction, so that the metal on the low potential side generates a galvanic current and the metal corrosion occurs on the metal on the low potential side.

  The mounting structure of an insulating washer for a disc brake disclosed in Patent Document 1 discloses a structure in which a support for a disc brake formed of an iron material is fastened with a mounting bolt to a knuckle formed of an aluminum material. In this structure, an adhesive coating layer is formed on one side of an insulating washer on which a zinc dust chromium oxide film is formed, and the insulating washer is temporarily fixed by being fitted to a plurality of protrusions previously formed on a disc brake support. After bonding, the disc brake support is fastened with an insulating washer sandwiched between the knuckles.

JP-A-11-303906

In the mounting structure of the disc brake insulating washer of Patent Document 1, since the insulating washer is temporarily fixed to the disc brake support in advance, the insulating washer is attached to the disc brake support with a simple configuration so that it cannot be dropped off. be able to.
In addition, since an insulating washer is interposed between the aluminum material knuckle and the iron disc brake support so as not to fall off, it is possible to prevent the occurrence of electrolytic corrosion of the knuckle due to the potential difference between iron and aluminum. .

  However, in the structure of Patent Document 1, since it is necessary to form a plurality of protrusions for fitting an insulating washer to the support of the disc brake, the support structure of the disc brake becomes complicated, and the manufacturing cost of the parts may increase. There is. Moreover, in order to fit the insulating washer, a process of applying an adhesive to one side of the insulating washer and a process of fitting the outer peripheral surface of the insulating washer to the inner peripheral surface of the plurality of protrusions are newly generated and assembled. Since the efficiency is reduced, the production cost may increase.

  An object of the present invention is to provide a dissimilar metal member mounting structure and its mounting method capable of simplifying the member structure and improving the efficiency of assembly work while preventing the electrolytic corrosion of the member in the mounting of dissimilar metal members. Is to provide.

  In the mounting structure for dissimilar metal members according to claim 1, the cylindrical portion of the second member made of iron-based material is fitted into the shaft member provided on the first member made of light metal material via an annular washer. In the attachment structure of the dissimilar metal member in which the member and the second member are fastened by bolts, an insulating plate is provided which is attached to the washer and interposed between the washer and the first member, An engaging portion that engages with a washer, an opening through which the shaft member can be inserted, and when the shaft member is inserted through the opening, elastically contact the shaft member to cause the washer to move relative to the shaft member. It is characterized by having an elastic support part to regulate.

  In this dissimilar metal member mounting structure, since the insulating plate interposed between the washer and the first member is provided, the first member and the second member having a higher potential than the first member are electrically connected by the insulating plate. The first member can be reliably prevented from being corroded by electric corrosion, and the fastening force at the time of fastening can be maintained.

According to a second aspect of the present invention, in the first aspect of the invention, the engaging portion includes a plurality of engaging claws that extend from an outer edge portion of the insulating plate and engage with an outer peripheral portion of the washer. Is composed of a plurality of contact claws extending from the opening in the axial direction of the shaft member.
According to a third aspect of the invention, in the first or second aspect of the invention, the first member is a wheel hub member, and the second member is an attachment portion of a suspension damper.

  According to a fourth aspect of the present invention, the dissimilar metal member is attached to the shaft member provided on the first member made of light metal material by fitting the cylindrical portion of the second member made of iron-based material through an annular washer. In the method of attaching a dissimilar metal member that fastens the first member and the second member with bolts, an engagement portion that can be engaged with the washer, an opening portion through which the shaft member can be inserted, and an elasticity that can be elastically contacted with the shaft member A first step in which an insulating plate provided with a support portion is manufactured in advance, and the shaft member is inserted into the opening of the washer on which the insulating plate is mounted, thereby restricting the movement of the washer with respect to the shaft member; The second member is fitted into the shaft member, and the first member and the second member are fastened by the bolt in a state where the insulating plate is interposed between the washer and the first member. And a process.

  The invention of claim 5 is characterized in that, in the invention of claim 4, the first member is a wheel hub member, and the second member is a mounting portion of a suspension damper.

  According to the first aspect of the present invention, since the insulating plate has the engaging portion, a washer assembly including the washer and the insulating plate can be formed, and the two parts of the washer and the insulating plate are provided in the first member. The shaft member can be assembled by a single insertion operation. Further, since the insulating plate has the elastic support portion, the two parts of the washer and the insulating plate can be temporarily fixed to the shaft member so that they cannot be detached in the positioning state simultaneously with the insertion operation. Thereby, in the attachment of a dissimilar metal member, the member structure can be simplified and the efficiency of the assembly work can be improved while preventing the electrolytic corrosion of the member, and the manufacturing cost and production cost of the parts can be suppressed.

According to the invention of claim 2, in addition to the effect of the invention of claim 1, the structure of the insulating plate that can be attached to the washer can be simplified.
According to the invention of claim 3, in addition to the effects of the inventions of claims 1 and 2, the wheel hub member can be reduced in weight while preventing electric corrosion of the wheel hub member, and the assembly of the wheel hub member and the suspension damper can be prevented. Efficiency can be improved.

According to the invention of claim 4, it is possible to obtain a method of attaching a member that basically exhibits the same effect as that of the invention of claim 1.
According to the invention of claim 5, in addition to the effect of the invention of claim 4, basically the same effect as that of the invention of claim 3 can be obtained.

It is a perspective view of the rear suspension provided with the attachment structure of the dissimilar metal member which concerns on Example 1 of this invention. It is a longitudinal cross-sectional view of the connection structure of a wheel hub member and the attachment part of a suspension damper. It is a disassembled perspective view of a washer and an insulating plate. It is a front view of the washer assembly which attached the insulating board to the washer. It is a side view of a washer assembly. It is the VI-VI sectional view taken on the line of FIG. It is a figure which shows the process of mounting | wearing a wheel hub member with a shaft member. It is a figure which shows a washer mounting | wearing process. It is a figure which shows a damper fastening process.

  DETAILED DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention will be described based on an embodiment applied to a rear suspension of an automobile. In FIG. 1, the direction of the arrow F will be described as the front, and the direction of the arrow L as the left.

Embodiment 1 of the present invention will be described below with reference to FIGS.
As shown in FIG. 1, a rear suspension 1 of this embodiment includes a suspension member 2 extending in the vehicle width direction, a pair of left and right subframes 3, a pair of left and right wheel hub members 4, and a pair of left and right upper arms. 5, a pair of left and right lower arms 6, a pair of left and right trailing arms 7, a pair of left and right suspension dampers 8, a pair of left and right coil springs 9, and the like.

  A pair of left and right subframes 3 extending in the front-rear direction are fixed to the left and right ends of the suspension member 2, respectively. The pair of left and right subframes 3 are formed in a curved shape in plan view so as to be spaced apart in the vehicle width direction toward the front and rear direction end portions. A pair of front and rear connecting portions 3a are provided at the front and rear ends of the pair of left and right subframes 3, respectively, and these connecting portions 3a are fixed to a vehicle body (not shown) via elastic mounts. Since the rear suspension 1 has the same configuration in the left-right symmetry, the rear suspension provided on the right rear wheel will be mainly described below.

As shown in FIG. 1, the upper arm 5, the lower arm 6, the trailing arm 7 and the like constitute a suspension link of the rear suspension 1, and these links are connected to a wheel hub member 4 that rotatably supports a wheel (not shown). Has been.
The upper arm 5 extends in the vehicle width direction, and the left side (vehicle width direction inner side) end portion is swingably connected to the mounting portion 2a of the suspension member 2 via an elastic bush, and the right side (vehicle width direction outer side) end portion is connected. The upper part of the wheel hub member 4 is swingably connected via an elastic bush.

  The lower arm 6 extends in the vehicle width direction at a position below the upper arm 5, the left end thereof is swingably connected to the mounting portion 2 b of the suspension member 2 via an elastic bush, and the right end is connected via an elastic bush. The lower part of the wheel hub member 4 is swingably connected. A support portion (not shown) for supporting the lower end of the coil spring 9 is provided in the middle of the lower arm 6.

The trailing arm 7 extends in the front-rear direction, the front end 7 a is connected to a rear side frame (not shown) via an elastic bush, and the rear end 7 b is connected to the front side portion of the wheel hub member 4 by three bolts and nuts 10. It is fixed. Bolt holes are formed in the rear end portion 7b of the trailing arm 7 and the front portion of the wheel hub member 4, respectively.
The trailing arm 7 is configured to be swingable in the vertical direction about the front end 7a with respect to the vehicle body, and swings in the vertical direction so that the wheel hub member 4 and the wheel draw a locus centered on the front end 7a. To do. Since the trailing arm 7 is twisted by a predetermined amount with respect to a predetermined load, the camber change of the wheel hub member 4 and the wheel can be allowed.

The wheel hub member 4 is integrally formed by casting an aluminum alloy whose main material is aluminum. As shown in FIGS. 1 and 2, the wheel hub member 4 is provided with a cylindrical recess 4b extending in the vehicle width direction on the left side corresponding to the shaft of the right hub 4a. A shaft member 11 having a heart is fitted and connected to the recess 4b.
The shaft member 11 is made of steel whose main material is iron, and a threaded portion 11a extending in the axial direction is formed on the left side portion. When the shaft member 11 is fitted and connected to the recess 4b, the shaft member 11 has a length corresponding to the axial length of the screw portion 11a so as to protrude from the left end 4c of the wheel hub member 4 to the left. It is configured.

As shown in FIGS. 1 and 2, the suspension damper 8 includes a main body portion 8 a extending in the vertical direction and having an upper end coupled to the vehicle body, and a rod portion extending downward from the lower end of the main body portion 8 a and freely movable up and down. 8b, a cylindrical mounting portion 8c provided at the lower end of the rod portion 8b, and a cylindrical bush 12 (cylindrical portion). The mounting portion 8c is provided with a cylindrical opening that is coaxial with the shaft member 11 and has an inner diameter larger than that of the shaft member 11, and a bush 12 is fitted into the inner periphery thereof.
The bush 12 is made of steel, mainly steel, specifically steel, and has an inner diameter that can be fitted onto the shaft member 11. The bush 12 has an axial length so that when the bush 12 is fitted to the mounting portion 8c, the left and right ends of the bush 12 protrude outward in the left-right direction from the left and right ends of the mounting portion 8c. Yes.

Next, a connection structure between the wheel hub member 4 and the suspension damper 8 will be described.
The mounting portion 8 c of the suspension damper 8 is fitted into the shaft member 11 via the washer assembly 20 and is fastened to the shaft member 11 by the fastening bolt 14 via the fastening washer 13.
As shown in FIGS. 2 to 6, the washer assembly 20 includes an annular washer 21 and an annular insulating plate 22. The washer 21 is configured to reduce the contact surface pressure between the left end 4 c of the wheel hub member 4 and the right end of the bush 12, and has an opening 21 a formed larger in diameter than the outer diameter of the shaft member 11. I have. The right side surface of the washer 21 is in surface contact with the main body 22 a of the insulating plate 22, and the left side surface of the washer 21 is in surface contact with the right end of the bush 12.
The surface of the washer 21 is subjected to a geomet treatment in order to form an insulating film in which metal flakes are layered and bonded with a silicon inorganic binder. The insulating film is not limited to geomet treatment, and may be formed by cation coating or the like.

The insulating plate 22 is interposed between the washer 21 and the left end 4c of the wheel hub member 4, and on the surface thereof, an insulating film in which metal flakes are layered and bonded by a silicon inorganic binder is formed. Geomet processing is applied.
As shown in FIGS. 2 to 6, the insulating plate 22 has an annular main body portion 22 a, a plurality of, for example, four engagement claws 22 b (engagement portions) formed every 90 degrees, and the shaft member 11 inserted therethrough. A possible opening 22c and a plurality of, for example, four contact claws 22d (elastic support portions) formed every 90 degrees are provided.

The right side surface of the main body portion 22 a is in surface contact with the left end portion 4 c of the wheel hub member 4, and the left side surface of the main body portion 22 a is in surface contact with the right side surface of the washer 21.
The engaging claw 22 b extends from the outer edge portion of the main body portion 22 a and is formed in a substantially L-shaped cross section, and is configured to be engageable with the outer peripheral portion of the washer 21. As shown in FIGS. 3, 5, and 6, a recessed portion 22 e that is recessed in the axial direction is formed in an intermediate portion of the engaging claw 22 b. The inner diameter of the opening 22 c is set larger than the outer diameter of the shaft member 11.

  The contact claw 22d extends from the opening 22c in an inclined direction in the axial direction of the shaft member 11, and is formed so as to be closer to the axial direction as the distance from the opening 22c increases. The contact claw 22d elastically contacts the outer periphery of the shaft member 11 when the shaft member 11 is inserted through the opening 22c (21a), and restricts the movement of the washer assembly 20 (washer 21) relative to the shaft member 11. Has elastic force. Each contact claw 22d is arranged at a position corresponding to the middle between the adjacent engagement claws 22b.

A procedure for attaching the wheel hub member 4 and the suspension damper 8 will be described with reference to FIGS.
First, the insulating plate 22 includes four engaging claws 22b that can be engaged with the washer 21, an opening 22c through which the shaft member 11 can be inserted, and four contact claws 22d that can elastically contact the shaft member 11. Is prepared in advance, and a preparatory step for preparing the washer assembly 20 by attaching the insulating plate 22 to the washer 21 is performed. Further, in the axle assembly process in parallel with the preparation process, the shaft member 11 is fitted and connected to the recess 4b of the wheel hub member 4 as shown in FIG.

Next, as shown in FIG. 8, a washer mounting step (first step) is performed in the axle assembly step.
In the washer mounting step, the shaft member 11 is inserted into the opening 22c (21a) of the washer assembly 20. In order to set the mounting posture of the washer assembly 20 so that the right side surface of the main body portion 22a is in surface contact with the left end portion 4c of the wheel hub member 4, the shaft member 11 is formed from the base end side of the contact claw 22d having a large diameter. The tip (left end) is inserted. Accordingly, the insertion operation can be facilitated, and the contact claw 22d elastically contacts the outer periphery of the shaft member 11 to restrict the movement of the washer assembly 20 with respect to the shaft member 11, so that the washer assembly 20 is positioned. It can be temporarily fixed so that it cannot be dropped.

Next, as shown in FIG. 9, a damper tightening step (second step) is performed in the vehicle assembly step.
In the damper tightening step, the bush 12 fitted in the mounting portion 8c of the suspension damper 8 is fitted into the shaft member 11 to which the washer assembly 20 is temporarily fixed, and the insulating plate 22 is attached to the left end of the washer 21 and the wheel hub member 4. The wheel hub member 4 and the suspension damper 8 are fastened by the fastening bolts 14 while being interposed between the portions 4c. Thus, the aluminum alloy wheel hub member 4 and the steel bush 12 can be electrically insulated by the insulating washer 21 and the insulating plate 22, and the wheel hub member 4 is caused by electrolytic corrosion caused by a potential difference between metals. Prevents corrosion.

Next, functions and effects of the dissimilar metal member mounting structure according to the embodiment will be described.
According to this dissimilar metal member mounting structure, since the insulating plate 22 interposed between the washer 21 and the wheel hub member 4 is provided, the aluminum alloy wheel hub member 4 and the wheel hub member 4 have a higher potential. The steel bush 12 can be electrically insulated by the insulating plate 22 and fastened, and corrosion of the wheel hub member 4 due to electric corrosion can be reliably prevented, and the fastening force at the time of fastening can be maintained. Since the insulating plate 22 has the engaging portion (engaging claw 22b), the washer assembly 20 integrally including the washer 21 and the insulating plate 22 can be configured, and the two parts of the washer 21 and the insulating plate 22 are combined with the wheel hub. The shaft member 11 provided on the member 4 can be assembled by a single insertion operation. Further, since the insulating plate 22 has an elastic support portion (contact claw 22d), at the same time as the insertion operation, the two parts of the washer 21 and the insulating plate 22 are temporarily fixed to the shaft member 11 so as not to fall off. be able to. Thereby, in the attachment of a dissimilar metal member, while preventing the electric corrosion of the wheel hub member 4, it is possible to simplify the member structure and improve the efficiency of the assembling work, and to suppress the production cost and production cost of the parts. .

  The engaging portion includes a plurality of engaging claws 22b extending from the outer edge portion of the insulating plate 22 and engaging the outer peripheral portion of the washer 21, and the elastic supporting portion extends from the opening portion 22c in the axial direction of the shaft member 11. Therefore, the structure of the insulating plate 22 that can be attached to the washer 21 can be simplified.

  Since the first member is the wheel hub member 4 and the second member is the attachment portion 8c (bush 12) of the suspension damper 8, the wheel hub member 4 can be reduced in weight while preventing electric corrosion of the wheel hub member 4. The assembly efficiency of the wheel hub member 4 and the suspension damper 8 can be improved.

  According to the attachment method of the dissimilar metal member, the engaging portion (engaging claw 22b) that can be engaged with the washer 21, the opening 22c through which the shaft member 11 provided on the wheel hub member 4 can be inserted, and the shaft member 11 An insulating plate 22 having an elastic support portion (abutment claw 22d) capable of elastic contact is prepared in advance, and the shaft member 11 is inserted into the opening 21a (22c) of the washer 21 to which the insulating plate 22 is attached. A washer mounting step for restricting the movement of the washer 21 relative to the shaft member 11, the bush 12 of the mounting portion 8 c of the suspension damper 8 is fitted into the shaft member 11, and the insulating plate 22 is interposed between the washer 21 and the wheel hub member 4. Since it includes a damper tightening step for fastening the wheel hub member 4 and the bush 12 with the fastening bolts 14 in the interposed state, the two parts of the washer 21 and the insulating plate 22 are used as the wheel. The shaft member 11 provided on the hub member 4 can be assembled by a single insertion operation, and at the same time as the insertion operation, the two parts of the washer 21 and the insulating plate 22 cannot be detached in the positioning state with respect to the shaft member 11. It can be temporarily fixed, and in the mounting of dissimilar metal members, while preventing the electric corrosion of the wheel hub member 4, it simplifies the member structure and improves the efficiency of the assembly work, and suppresses the production cost and production cost of parts. it can.

Next, a modification in which the above embodiment is partially changed will be described.
1) In the above embodiment, the shaft member is fitted and connected to the wheel hub member, and the suspension damper mounting portion is attached to the shaft member. However, the suspension damper is attached to the shaft member integrally formed with the wheel hub member. You may attach the attachment part. Also, any dissimilar metal member having a potential difference may be attached, not limited to the combination of the wheel hub member and the suspension damper attachment part, but a knuckle formed of an aluminum material and a disc brake support formed of an iron material, etc. Various combinations are possible.

2] In the above-described embodiments, examples of the first member made of aluminum alloy and the second member made of steel have been described. However, the present invention is not limited to this combination. As the light metal material, any metal can be applied as long as it is a low potential base metal having a high ionization tendency with respect to the second member such as aluminum or magnesium alloy in addition to the aluminum alloy. In addition to steel, any metal can be used as long as it is a high-potential noble metal having a low ionization tendency with respect to the first member such as iron or steel.

3) In addition, those skilled in the art can implement the present invention by adding various modifications to the embodiments without departing from the spirit of the present invention, and the present invention includes such modifications. is there.

  In the present invention, a cylindrical portion of a second member made of a high-potential iron-based material is fitted into a shaft member provided on a first member made of a low-potential light metal material via an annular washer. In the mounting structure and method of dissimilar metal members, which are fastened with bolts, by providing an insulating plate that engages with a washer and that can be temporarily fixed to a shaft member so that the shaft member cannot be detached. Simplification of member structure and efficiency of assembly work can be achieved while preventing food.

DESCRIPTION OF SYMBOLS 1 Rear suspension 4 Wheel hub member 8 Suspension damper 8c Attaching part 11 Shaft member 12 Bushing 14 Fastening bolt 20 Washer assembly 21 Washer 22 Insulating plate 22b Engaging claw 22c Opening part 22d Abutting claw

Claims (5)

The cylindrical portion of the second member made of iron-based material is fitted into the shaft member provided on the first member made of light metal material via an annular washer, and the first member and the second member are fastened by bolts. In the mounting structure of dissimilar metal members,
An insulating plate attached to the washer and interposed between the washer and the first member;
The insulating plate engages with the washer, an opening through which the shaft member can be inserted, and when the shaft member is inserted through the opening, the insulating plate elastically contacts the washer. An attachment structure for dissimilar metal members, comprising: an elastic support portion that restricts movement of the shaft relative to the shaft member.   The engaging portion includes a plurality of engaging claws that extend from an outer edge portion of the insulating plate and engage with an outer peripheral portion of the washer, and the elastic support portion extends from the opening in the axial direction of the shaft member. The dissimilar metal member mounting structure according to claim 1, comprising a plurality of contact claws.   The dissimilar metal member mounting structure according to claim 1, wherein the first member is a wheel hub member, and the second member is a suspension damper mounting portion. A dissimilar metal in which a cylindrical portion of a second member made of iron-based material is fitted into a shaft member provided on a first member made of light metal material via an annular washer, and the first member and the second member are fastened by bolts In the mounting method of the member,
An insulating plate having an engaging portion engageable with the washer, an opening through which the shaft member can be inserted, and an elastic support portion capable of elastic contact with the shaft member is manufactured in advance.
A first step of restricting the movement of the washer relative to the shaft member by inserting the shaft member through the opening of the washer to which the insulating plate is mounted;
The second member is fitted into the shaft member, and the first member and the second member are fastened by the bolt in a state where the insulating plate is interposed between the washer and the first member. Process,
A method for attaching a dissimilar metal member.   The dissimilar metal member mounting method according to claim 4, wherein the first member is a wheel hub member, and the second member is a mounting portion of a suspension damper.