JP2001206248A - Fitting point slide structure of resin outer plate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a fitting point slide structure of resin outer plate capable of securing the fitting accuracy under any environmental condition by absorbing the extension and shrinkage of the resin outer plate. SOLUTION: An outer plate fitting flange part 9 of a car body panel 2 has a rectangular hole 10 having two opposite sides arranged along the fore and aft direction of slide. A base plate 3 for covering the rectangular hole is provided in a back surface of the rectangular hole, and the car body panel is pinched by the resin outer plate and the base plate with fasteners 4a, 4b passing through the resin outer plate 1, the car body panel and the base plate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a structure for sliding a mounting point of a resin outer plate.

[0002]

2. Description of the Related Art In order to mount a resin outer panel having a large coefficient of linear expansion to a vehicle body, various mounting methods have been tried. However, the resin outer panel not only expands and contracts with temperature but also has a similar shape. Since the thickness also changed, the mounting structure was inevitably complicated.

[0003] As a conventional structure for sliding a mounting point of a resin outer plate, there has been one disclosed in, for example, Japanese Utility Model Publication No. 60-54959. In this prior art, a long hole is provided in a vehicle body panel, and a flanged nut slides on an edge protector fixed to the long hole, thereby absorbing expansion and contraction of a resin outer plate.

[0004]

However, in such a conventional sliding structure of the mounting point of the resin outer plate, since the resin outer plate expands and contracts and the plate thickness also changes, the fastening method is difficult. The axial force applied to the tool and the frictional force applied to the edge protector also changed, and there was a problem that the slide did not work well.

Further, since the axial force applied to the fastener largely depends on environmental conditions such as temperature at the time of mounting, there is a problem that the mounting accuracy of the resin outer plate greatly varies depending on the environmental conditions at the time of mounting. Was.

The present invention has been made in view of such a conventional problem, and absorbs expansion and contraction of a resin outer plate without changing an axial force applied to a fastener, and can be used under any environmental conditions. It is another object of the present invention to provide a slide structure for a mounting point of a resin outer plate, which can ensure mounting accuracy.

[0007]

According to a first aspect of the present invention, there is provided an outer panel made of a thermoplastic resin having a large linear expansion coefficient. In a structure that is slidably attached to a reference position of a vehicle body panel formed of a casting such as a light alloy, a rectangular hole having two opposite sides along a sliding front-rear direction is formed on an outer plate mounting flange portion of the vehicle body panel. Having a base plate covering the rectangular hole on the back surface of the rectangular hole,
Two sides perpendicular to the sliding direction of a surface of the rectangular hole facing the base plate by sandwiching the body panel between the resin outer plate and the base plate by a fastener penetrating the resin outer plate, the vehicle body panel, and the base plate. On the upper side, there are thick portions having a convex cross-section projecting toward the base plate, and at each position on the base plate with respect to the two convex thick portions, the convex thick portion is provided. And two slopes of the respective V-shaped grooves located on the side far from the reference position of the outer panel are in line contact with the convex thick portions, respectively. And, at least the angle between the two slopes that are in contact with the convex thick portion is substantially the distance from the reference position of the resin outer plate to the center of the fastener, and the plate thickness of the resin outer plate is the numerator. Tangent It is characterized in that the angle.

According to a second aspect of the present invention, in the sliding structure for attaching a resin outer plate according to the first invention, a hole for penetrating the fastener of the resin outer plate is provided. A diameter that ensures a clearance that does not always contact the shaft diameter of the fastener, and the entire circumference of the hole on the vehicle body panel side is a denominator of a maximum radius of the hole, and a thickness of the resin outer plate. And the entire circumference of the through hole for the fastener of the base plate on the resin outer plate side is conical with the mortar-shaped chamfer surface. And the peripheral side surface of the molding portion and the chamfered chamfered surface are in contact with each other.

According to a third aspect of the present invention, in the sliding structure for attaching a resin outer plate according to the first or second aspect of the present invention, the convex thick portion of the vehicle body panel is provided with the vehicle body panel. It is characterized in that it is formed integrally with the same.

According to a fourth aspect of the present invention, in the slide structure for attaching a resin outer plate according to any one of the first to third aspects, the convex thick portion of the vehicle body panel includes: A hole of a convex thick portion of two sides that is present on all four sides of the rectangular hole and along two sides along the sliding direction of the base plate in the sliding direction of the rectangular plate in any sliding state. It is characterized in that the base plate and the rectangular hole are always in a state of being fitted to each other with a slidable clearance therebetween while being located inside the side inner wall surface, and being always fitted.

Further, a fifth invention according to claim 5 is as follows.
In the sliding structure of the resin outer plate according to any one of the first to fourth inventions, the base plate is an integrally molded product such as a light alloy, and has a symmetrical shape centered on the through hole for the fastener. It is characterized by the following.

[0012]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an exploded perspective view showing an embodiment of a slide structure of a resin outer plate according to the present invention.

(First Embodiment) FIGS. 1 to 6 are views showing a first embodiment of a structure for sliding a mounting point of a resin outer plate according to the present invention. 1 is an overall perspective view showing a configuration of a slide structure of a mounting point of a resin outer plate, FIG. 2 is an enlarged perspective view of a mounting portion viewed from a back surface, FIG. 3 is an enlarged sectional view along a sliding direction, and FIG. 5 is an enlarged sectional view in a direction perpendicular to the sliding direction, FIG. 5 is an enlarged sectional view at a high temperature along the sliding direction, and FIG. 6 is an enlarged sectional view at a low temperature along the sliding direction.

First, the configuration will be described. In the sliding structure of the mounting point of the resin outer panel according to the first embodiment, the outer panel 1 made of a thermoplastic resin is interposed between the body panel 2 made of a casting such as a light alloy and the base plate 3. With the fasteners 4a and 4b, the fastening distance 4
9 is attached. The resin outer plate 1 is positioned at the reference position 5
, The fastener 4b penetrates through the mounting flange 7 of the resin outer plate 1, and the clearance 3 which does not always contact the shaft diameter 30 of the fastener 4b.
The mounting flange 9 of the vehicle body panel 2 has a rectangular hole 10 along two sides facing the sliding direction 6.

On the base plate 3 side of two sides 11a and 11b perpendicular to the sliding direction 6 of the rectangular hole 10, convex thick portions 12a and 12b formed integrally with the vehicle body panel 2 are provided.
And V-shaped grooves 13a and 13 on the base plate 3.
b. At least the slopes 14a and 14b of the V-shaped grooves 13a and 13b farther from the reference position 5 are tangents with the distance 16 from the reference position 5 to the fastener center 15 as a denominator and the thickness 17 of the resin outer plate 1 as a numerator. A clearance 19 between the resin outer plate 1 and the base plate 3 which has a configured angle 18 and does not contact in any sliding state.
And the convex thick portions 12a and 12a facing each other while having a clearance 48 between the vehicle body panel 2 and the base plate 3 which does not contact in any sliding state.
is in line contact with b.

The entrance 20 of the hole 8 for penetrating the fastener 4b of the resin outer panel 1 on the vehicle body panel 2 side has a maximum radius 2 of the hole 8.
1 is a denominator, the entire circumference is chamfered at an angle 22 formed by a tangent having the thickness 17 of the resin outer plate 1 as a numerator, and the resin plate 1 side entrance 24 of the fastener through hole 23 of the base plate 3 is The holes 8 of the resin outer panel 1 are formed at the same angle 22 as the entrance 20 on the vehicle body panel 2 side, and are in contact with each other.

The base plate 3 includes fasteners 4a and 4
b has a symmetrical shape centered on the through hole 8, and the outer surfaces 25a and 25b of the base plate 3 have two sides 26a along the sliding direction 6 of the rectangular hole 10 of the vehicle body panel in any sliding state. 26b, which are located inside the inner side surfaces 28a and 28b of the protruding thick portions 27a and 27b on the base plate 3 side and are close to each other with slidable clearances 29a and 29b.
“0” is a state of being always fitted.

Next, the operation of the first embodiment will be described. First, the operation at a high temperature will be described. At a high temperature, the outer plate 1 formed of the thermoplastic resin moves from the reference position 5 in the extending direction 33 to have a distance 16a whose distance from the reference position has increased, and at the same time has a plate thickness 17a whose thickness has increased. Further, the diameter 32 and the maximum radius 21 of the hole 8 for penetrating the fastener 4b of the resin outer plate 1 are the enlarged diameter 32a and the maximum radius 21a, respectively.

When the resin outer plate 1 and the base plate 3 move in the extension direction 33, the base plate 3 is moved by the amount corresponding to the increase in the plate thickness 17 to the slopes 14 of the V-shaped grooves 13a and 13b.
a and 14b approaching the direction 34 toward the resin skin 1, and at the same time the diameter 32 of the fastener through hole 8 of the resin skin 1 increases, so that the base plate 3
Since it enters the resin outer plate 1 along the 0 slope, the fastening distance 49 does not change, and the axial force of the fastener does not change. Also,
Since the hole entrance 24 of the base plate 3 enters the resin outer plate 1 while supporting the fastener 4b, the fastener center 15 with respect to the fastener through hole 8 on the resin outer plate 1 side does not change.

Next, the operation at a low temperature will be described. At a low temperature, the outer panel 1 formed of a thermoplastic resin is
Moving from the reference position 5 in the contraction direction 35, the distance from the reference position decreases to a distance 16b, and at the same time, the plate thickness also decreases to a plate thickness 17b. The diameter 32 and the maximum radius 21 of the hole 8 for penetrating the fastener 4b of the resin outer plate 1 are as follows.
Each has a reduced diameter 32b and a maximum radius 21b.

When the resin outer plate 1 and the base plate 3 move in the extending direction 33, the base plate 3 is moved by the increased amount of the plate thickness 17 to the slopes 14 of the V-shaped grooves 13a and 13b.
a and 14b, moving away from the resin skin 1 in the direction 36, and at the same time, the fastener through holes 8 in the resin skin 1
As the diameter 32 of the base plate 3 decreases, the base plate 3 goes out of the resin outer plate 1 along the slope of the inlet 20, so that the fastening distance 49 does not change and the axial force of the fastener does not change. Further, since the hole entrance 24 of the base plate 3 goes out of the resin outer plate 1 while supporting the fastener 4b, the fastener center 15 with respect to the fastener through hole 8 on the resin outer plate 1 side does not change.

As described above, the fastener axial force does not change under any temperature conditions, and the fastener through hole 8
Is not changed, so that the resin outer plate 1
Can slide smoothly. Moreover,
The fastener axial force does not change under any temperature conditions, and the fastener center 15 with respect to the fastener through hole 8 of the resin outer plate 1 does not change.
The resin outer plate 1 can be attached to the vehicle body panel 2, and the attachment accuracy can be improved.

In addition to these effects, in the first embodiment, the outer surfaces 25a and 25b of the base plate 3 are provided.
Are two sides 26a and 2a along the sliding direction 6 of the rectangular hole 10 of the vehicle body panel in any sliding state.
6b of the base plate 3 side convex thick portions 27a and 27
b are located inside the inner side surfaces 28a and 28b,
Since the base plate 3 and the rectangular hole 10 of the vehicle body panel are always fitted to each other with the slidable clearances 29a and 29b close to each other, the base plate 3 rotates when the fasteners 4a and 4b are tightened at the time of installation. Is suppressed, and the mountability is improved.

Further, in addition to these effects, in the first embodiment, the base plate 3 is an integrally molded product such as a light alloy, and has a symmetrical shape about the through holes 8 of the fasteners 4a and 4b. As a result, the number of parts can be reduced, and at the same time, high rigidity can be ensured and there is no difference in function depending on the mounting direction, so that the mountability is improved.

(Second Embodiment) FIG. 7 is a view showing a second embodiment of the structure for sliding a mounting point of a resin outer plate according to the present invention. FIG. 7 is an enlarged cross-sectional view along the sliding direction.

In the second embodiment, two sides 11a and 1a perpendicular to the sliding direction 6 of the rectangular hole 10 of the vehicle body panel 37 are provided.
1b, convex cross-sections 38a and 38a on the base plate side.
8b is formed by bending the outer periphery of the rectangular hole 10 outward, and in this embodiment, even when the vehicle body panel 37 is formed with a uniform thickness, the same as in the first embodiment is applied. The effect can be obtained.

(Third Embodiment) FIG. 8 is a view showing a third embodiment of a slide structure for a mounting point of a resin outer plate according to the present invention. FIG. 8 is an enlarged cross-sectional view along the sliding direction.

In the third embodiment, the base plate 39
Is formed of a highly rigid uniform plate material, and the same effect as that of the first embodiment can be obtained by a simpler forming method of the base plate 39 such as press working while reducing the weight of the base plate 37. it can.

(Fourth Embodiment) FIG. 9 is a view showing a fourth embodiment of a structure for sliding a mounting point of a resin outer plate according to the present invention. FIG. 9 is an enlarged cross-sectional view along the sliding direction.

In the fourth embodiment, the base plate 40
Is asymmetrical with respect to the sliding direction 6, but also in this embodiment, the resin outer plate slides smoothly without changing the fastening distance 49 and the fastening axial force under any temperature condition. Improves mounting accuracy, suppresses rotation of base plate 40 during mounting,
The mounting property can be improved.

(Fifth Embodiment) FIG. 10 is a view showing a fifth embodiment of the structure for sliding a mounting point of a resin outer plate according to the present invention. FIG. 10 is an enlarged cross-sectional view along the sliding direction.

In the fifth embodiment, V-shaped grooves 42a and 42b are provided on the base plate 43 on two sides of the rectangular hole 10 of the vehicle body panel 41, which is perpendicular to the sliding direction 6, and at least the side near the reference position 5 Slope 45a and 45b
Is a denominator of a distance 16 from the reference position 5 to the center 15 of the fastener, and an angle 18 composed of a tangent having a thickness 17 of the resin outer plate 1 as a numerator. The resin outer plate 1 does not contact in any sliding state. And the clearance 46 between the base plate 43 and the body panel 41 and the clearance 47 between the base plate 43 that do not come into contact with each other in any sliding state, and are in line contact with the convex thick portions 44a and 44b provided on the base plate 43. Therefore, the same effect as in the first embodiment can be obtained.

[0033]

As described above, according to the present invention, the following effects can be obtained. According to the first aspect of the present invention, the outer panel formed of a thermoplastic resin having a large linear expansion coefficient can be slid with respect to a reference position of a vehicle body panel formed of a casting such as a light alloy. In the mounting structure, the outer plate mounting flange portion of the vehicle body panel has a rectangular hole having two sides facing each other along the slide front-rear direction, and a base plate covering the rectangular hole is applied to the back surface of the rectangular hole. By a fastener penetrating the resin outer plate, the vehicle body panel, and the base plate,
The thickness of the convex cross-section protruding toward the base plate is on two sides of the rectangular hole facing the base plate at right angles to the sliding direction, with the body panel interposed between the resin outer plate and the base plate. And a V-shaped groove at each position on the base plate with respect to the two convex thick portions, the V-shaped groove engaging with the convex thick portion. The two slopes located on the side of the groove farther from the reference position of the outer panel are in line contact with the convex thick portions, respectively, and at least the angles of the two slopes contacting the convex thick portions. Since the distance from the reference position of the resin outer plate to the center of the fastener is a denominator, the mounting point of the resin outer plate is an angle formed by a tangent having the thickness of the resin outer plate as a numerator.
For example, when the resin outer plate expands at a high temperature to increase the plate thickness, the base plate slides in the direction in which the resin outer plate extends, and at the same time, approaches the resin outer plate side by the plate thickness increase, and at a low temperature, When the resin outer plate shrinks to reduce the plate thickness, the base plate slides in the direction in which the resin outer plate contracts, and at the same time, moves away from the resin outer plate by the reduced thickness, so that the fastening is performed under any temperature conditions. The resin outer plate can be slid smoothly without changing the axial force of the tool, and the axial force can be set constant under any mounting conditions.

According to a second aspect of the present invention, there is provided the slide structure for attaching the resin outer plate according to the first aspect of the present invention, wherein the fastener of the resin outer plate is penetrated. The hole has a diameter ensuring a clearance that does not always contact the shaft diameter of the fastener, and the entire circumference of the hole on the vehicle body panel side defines the maximum radius of the hole as a denominator, and the resin outside. The entire thickness of the through hole for the fastener of the base plate on the side of the resin outer plate is chamfered in the shape of a mortar. It is formed in a conical shape in accordance with the shape, and the peripheral side surface of the formed portion and the chamfered chamfered surface are characterized by being in contact with each other, for example, when the hole for the fastener of the resin outer plate is enlarged at a high temperature. A conical shaped part of the base plate Since it enters the resin outer plate while being in contact with the mortar-shaped chamfered surface of the resin outer plate, the center of the fastener hole of the resin outer plate and the center of the fastener hole of the base plate are kept coincident, and When the hole for the fastener of the resin outer plate is reduced at a low temperature, the conical molded portion of the base plate separates from the resin outer plate while being in contact with the mortar-shaped chamfer surface of the resin outer plate, Since the center of the fastener hole of the resin outer plate and the center of the fastener hole of the base plate are kept coincident, the mounting position accuracy can be ensured under any mounting conditions.

According to a third aspect of the present invention, there is provided the sliding structure for mounting the resin outer plate according to the first or second aspect of the present invention, wherein the convex thick portion of the vehicle body panel is provided. ,
Since it is characterized by being formed integrally with the vehicle body panel, the number of parts can be reduced, the shape can be simple, and the rigidity can be increased.

According to a fourth aspect of the present invention, there is provided the sliding structure of the mounting point of the resin outer plate according to any one of the first to third aspects, wherein the convex body of the vehicle body panel is provided. Thick portions are present on the entire four sides of the rectangular hole, and the two sides along the sliding direction of the base plate, in any sliding state, have two sides of convex meat facing each other along the sliding direction of the outer periphery of the rectangular hole. Since it has a shape close to the slidable clearance while being located inside the hole side inner wall surface of the thick portion, and the base plate and the rectangular hole are always in a fitted state,
When the base plate slides, a convex thick portion on two sides along the sliding direction serves as a slide guide for the base plate, and serves as a positioning and rotation suppressing mechanism when the base plate is attached with a fastener. Can be.

According to a fifth aspect of the present invention, there is provided the sliding structure for mounting the resin outer plate according to any one of the first to fourth aspects, wherein the base plate is made of a light alloy or the like. The product is characterized in that it is a symmetrical shape centered on the through hole for fasteners, so the number of parts can be reduced, a simple shape and high rigidity can be obtained, and a symmetrical shape Therefore, it can be easily attached.

[Brief description of the drawings]

FIG. 1 is an overall perspective view showing a configuration of a first embodiment of a mounting structure of a resin outer plate at a mounting point according to the present invention.

FIG. 2 is an enlarged perspective view of a mounting portion according to the first embodiment as viewed from a back surface.

FIG. 3 is an enlarged cross-sectional view of the first embodiment along a sliding direction.

FIG. 4 is an enlarged cross-sectional view of the first embodiment in a direction perpendicular to a sliding direction.

FIG. 5 is an enlarged cross-sectional view of the first embodiment at a high temperature along a sliding direction.

FIG. 6 is an enlarged cross-sectional view of the first embodiment at a low temperature along a sliding direction.

FIG. 7 is an enlarged sectional view of the second embodiment along a sliding direction.

FIG. 8 is an enlarged cross-sectional view of the third embodiment along a sliding direction.

FIG. 9 is an enlarged cross-sectional view of the fourth embodiment along a sliding direction.

FIG. 10 is an enlarged cross-sectional view of a fifth embodiment along a sliding direction.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Outer panel panel formed of thermoplastic resin 2, 41 Body panel formed of casting such as light alloy 3, 43 Base plate 4a, 4b Fastener 5 Reference fixing position of resin outer panel 6 Telescopic sliding direction 7 Resin outer panel 8 Mounting flange of resin outer panel 9 Hole for fastener through-hole 9 Mounting flange of vehicle body panel 10 Rectangular holes 11a, 11b Sides perpendicular to sliding direction of rectangular hole outer periphery 12a, 12b Convex thick portions 13a, 13b of vehicle body panel V-shaped grooves 14a, 14b Slope of V-shaped groove farther from reference position of resin outer plate 15 Center of fastener 16, 16a, 16b Distance from reference position of resin outer plate to center of fastener 17 Plate thickness of resin outer plate 18 Angle composed of tangent with the distance from the reference position of the resin skin to the center of the fastener as the denominator and the thickness of the resin skin as the numerator. 6 Clearance between resin outer plate and base plate 20 Body panel side entrance of fastener through hole of resin outer plate 21, 21a, 21b Maximum radius of fastener through hole of resin outer plate 22 Fastener through hole of resin outer plate The angle formed by the tangent with the maximum radius of the denominator as the denominator and the thickness of the resin outer plate as the numerator 23 The fastener through hole of the base plate 24 The resin outer plate side entrance of the fastener through hole of the base plate 25a, 26b The base plate Outer side surfaces 26a, 26b Surfaces along the sliding direction of the outer periphery of the rectangular hole 27a, 27b Thick convex portions along the sliding direction of the outer periphery of the rectangular hole 28a, 28b Protruding thick portions along the sliding direction of the outer periphery of the rectangular hole Inner side surface 29a, 29b Clearance between outer side surface of base plate and inner side surface of convex thick part 30 Shaft diameter of fastener 31 Shaft of fastener and fastener through resin outer plate 32, 32a, 32b Diameter of hole for passing fasteners through resin outer plate 33 Direction of extension at high temperature 34 Direction of movement of base plate at high temperature 35 Direction of contraction at low temperature 36 Direction of movement of base plate at low temperature 37 Body panel with uniform thickness 38 Folded projection of body panel 39 Base plate formed of uniform plate material 40 Base plates 42a, 42b formed asymmetrically in the sliding direction V-shaped grooves 44a, 44b provided on body panel Convex thick portions 45a, 45b Slope of V-shaped groove closer to reference position of resin outer plate 47, 48 Clearance between vehicle body panel and base plate 49 Fastening distance

Claims (5)

[Claims] 1. A structure in which an outer panel formed of a thermoplastic resin having a large linear expansion coefficient is slidably attached to a reference position of a body panel formed of a casting such as a light alloy. The outer plate mounting flange portion has a rectangular hole with two opposing sides along the slide front and rear direction, and a base plate covering the rectangular hole is applied to the back surface of the rectangular hole, and the resin outer plate and the vehicle body panel With the fasteners penetrating through the base plate, the body panel is sandwiched between the resin outer plate and the base plate, and two sides of the rectangular holes facing the base plate on two sides perpendicular to the sliding direction respectively face the base plate. It has a thick section with a convex cross section that protrudes,
At each position on the base plate with respect to the two convex thick portions, there is a V-shaped groove engaging with the convex thick portion, and the V-shaped groove of the outer panel of the respective V-groove is provided. The two slopes located on the far side from the reference position are in line contact with the convex thick portions, respectively, and at least the angle of the two slopes in contact with the convex thick portions is substantially equal to the reference of the resin outer plate. A mounting point slide structure for a resin outer plate, wherein a distance from a position to a center of the fastener is a denominator, and an angle formed by a tangent having a thickness of the resin outer plate as a numerator. 2. The resin outer panel mounting point slide structure according to claim 1, wherein a hole for penetrating the fastener of the resin outer panel is always in contact with a shaft diameter of the fastener. The diameter of the hole is defined by a tangent with the maximum radius of the hole being the denominator and the thickness of the resin outer plate being the numerator. The entire periphery of the entrance of the fastener through hole of the base plate on the resin outer plate side is formed into a conical shape in conformity with the mortar-shaped chamfer surface, and the peripheral side surface of the formed portion is chamfered in a mortar shape. And a mortar-shaped chamfer surface is in contact with the resin-made outer plate, wherein the mounting point slides. 3. The resin outer panel mounting point slide structure according to claim 1, wherein the convex thick portion of the vehicle body panel is formed integrally with the vehicle body panel. Slide structure for mounting point of outer plate. 4. The resin outer panel mounting point slide structure according to claim 1, wherein the convex thick portion of the vehicle body panel is present on all four sides of the rectangular hole. In any sliding state, the two side surfaces along the sliding direction of the base plate can slide while being located inside the hole-side inner wall surface of the convex thick portion of the two sides facing along the sliding direction of the outer periphery of the rectangular hole. A base plate and the rectangular hole are always fitted to each other with a suitable clearance, and a mounting point slide structure of the resin outer plate. 5. The sliding structure for mounting points of a resin outer plate according to claim 1, wherein the base plate is an integrally molded product of a light alloy or the like, and is centered on a through hole for a fastener. A sliding structure for a mounting point of a resin outer plate, which has a symmetrical shape.