JP7501955B2 - Elastic bush support structure - Google Patents

Description

The present invention relates to a support structure for an elastic bush that supports a supported member via an elastic body.

2. Description of the Related Art In suspensions for vehicles such as automobiles, vehicle body members such as the vehicle body and a subframe are connected to wheel side members such as a hub bearing housing via suspension arms (links) that can swing relative to these members.
Elastic bushings made of an elastic material such as rubber are provided at the connection points between the suspension links and vehicle body components, etc., for the purposes of suppressing vibration noise and obtaining compliance steer that utilizes elastic deformation to obtain the desired wheel displacement.

For example, Patent Document 1 describes a double wishbone rear suspension device that supports the rear wheels using an upper arm, front and rear lower links, and a trailing link. In general, elastic bushings are provided at one or both ends of such arms and links.
As prior art relating to a support structure for attaching such an elastic bush to a vehicle body member, for example, Patent Documents 2 and 3 describe a method in which both ends of an axial member inserted into the inner diameter side of a cylindrical elastic bush are made to protrude from the elastic body, and these protruding portions are fastened to fastening portions provided on the vehicle body side by mechanical fastening means such as bolts.
Furthermore, Patent Document 4 describes the use of a spherical seat and a hemispherical washer in a slidable and rotatable state in an automobile body structure in which a cabin and a side member are fastened with bolts via insulators in order to suppress a decrease in the fastening force of the bolts due to changes over time.

JP 2015-189339 A International Publication WO2011/148893A1 JP 2000-238662 A JP 2007-22207 A

In a structure in which a protruding portion (ear portion) protruding from an elastic bush is fastened to a vehicle body side member, as in Patent Documents 2 and 3, there is a concern that the fastening surface may become misaligned due to external forces input from the suspension links, etc. while the vehicle is traveling.
In response to this, measures may be taken such as increasing the fastening axial force of the bolts, etc., or forming protrusions on the seating surface to increase the coefficient of friction, but the support portion of the elastic bushing provided on the suspension link cannot necessarily receive a load in a direction that compresses the fastening seating surface against an external force due to assembly workability and the suspension stroke (swing of the arm, etc.), making it difficult to provide sufficient resistance to fastening misalignment.
Additionally, in order to ensure the strength of the fastening surface against large loads applied within the surface of the fastening surface, it is possible to consider enlarging the fastening surface, but during the manufacturing process, the enlarged fastening surface would need to be passed through the outer tube of the bush, which could lead to an increase in the size and weight of the entire bush.
In view of the above problems, an object of the present invention is to provide a support structure for an elastic bushing that has a simple structure and improves the reliability of the fastening points.

The present invention solves the above-mentioned problems by the following solving means.
According to one aspect of the present invention, a support structure for an elastic bushing has an elastic body formed in a cylindrical shape and having a supported member connected to its outer peripheral surface, and a fastening member held on the inner peripheral surface of the elastic body and fastened to a base, wherein the fastening member is fixed to the base by fastening a protruding portion protruding from an end face of the elastic body to a fastened portion formed on the base, and the contact surface of the protruding portion with the fastened portion is formed as a convex surface, and the contact surface of the fastened portion with the protruding portion is formed as a concave surface that makes surface-to-surface contact with the convex surface of the protruding portion, wherein the convex surface is formed as a convex curved surface that is eccentric to the opposite side to the fastened portion with respect to the central axis when viewed from the central axial direction of the elastic body, and the concave surface of the fastened portion is formed as a concave curved surface that makes surface-to-surface contact with the convex surface of the protruding portion .
With this, by making the contact surface of the protrusion with the fastened part convex, an external force input from the supported member along the radial direction of the elastic body (for example, a tensile or compressive force acting as the axial force of a suspension link) can be received in a state that generates a normal force between the contact surfaces over a wide range of input angles.
This suppresses misalignment of the contact surface due to external forces and, for example, when fastening with a bolt, reduces the bending force on the bolt, preventing bending deformation of the bolt and buckling of the bolt seat, thereby improving the reliability of the fastening point.
In addition, it is possible to suppress the need to increase the fastening surface area and the bolt diameter in order to improve resistance to large external forces, and it is possible to reduce the size and weight of the support structure for the elastic bushing.

Furthermore, by forming the concave surface of the fastened portion into a concave curved surface that comes into surface contact with the convex surface of the protruding portion, the above-mentioned effects can be obtained with a simple structure.

According to one aspect of the present invention, a support structure for an elastic bushing has an elastic body formed in a cylindrical shape and having a supported member connected to its outer peripheral surface, and a fastening member held on the inner peripheral surface of the elastic body and fastened to a base, wherein the fastening member is fixed to the base by fastening a protruding portion protruding from an end face of the elastic body to a fastened portion formed on the base, and the contact surface of the protruding portion with the fastened portion is formed as a convex surface, and the contact surface of the fastened portion with the protruding portion is formed as a concave surface that comes into surface contact with the convex surface of the protruding portion.The support structure for an elastic bushing is characterized in that the supported member is an oscillating member that oscillates within a predetermined angular range around the central axis of the elastic body, and when the oscillating member is within the angular range, when viewed from the central axial direction of the elastic body, a straight line that is in the same direction as the input direction from the oscillating member to the elastic body and passes through the center of action of the input intersects the convex surface of the protruding portion.
According to this, when a force acting in the axial direction of the oscillating member is input as an external force to the elastic bush, this input can be received in a state in which a normal force is reliably generated between the contact surfaces of the convex curved portion of the protrusion of the fastening member and the concave curved surface of the fastened part, thereby reliably preventing shifting of the contact surfaces and deformation of the bolt, etc. due to external forces, and improving the reliability of the fastening point.
Furthermore , the straight line may intersect with the convex surface at two points.
According to this, the above-mentioned effects can be obtained regardless of whether the axial force input from the fastened parts is in the compressive or tensile direction, and the reliability of the fastening points can be more reliably improved.

As described above, the present invention provides a support structure for an elastic bush that has a simple structure and improves the reliability of the fastening points.

1 is a schematic external perspective view of a suspension device having an embodiment of a support structure for an elastic bush to which the present invention is applied; 5A to 5C are diagrams illustrating a configuration of an elastic bush in the embodiment. 5 is a schematic cross-sectional view of a fastening portion between the elastic bush and the subframe in the embodiment. FIG. 11A and 11B are diagrams showing a configuration of an elastic bushing as a comparative example of the present invention.

Hereinafter, an embodiment of a support structure for an elastic bush to which the present invention is applied will be described.
The support structure for the elastic bushing according to the embodiment is provided, for example, in a double wishbone type suspension for the rear wheels of an automobile such as a four-wheeled passenger car.
FIG. 1 is a schematic external perspective view of a suspension device having an elastic bushing support structure according to an embodiment of the present invention.

The suspension device 1 is configured to include a subframe 10, a housing 20, a front lateral link 30, a rear lateral link 40, an upper link 50, a trailing link 60, a damper unit 70, a stabilizer device 80, etc.
Unless otherwise specified, the suspension device 1 has a substantially symmetrical configuration.

The subframe 10 is a structural member (vehicle body side member) that serves as the base to which each link of the suspension device 1 is attached, and is attached to the underfloor rear part of the vehicle body (not shown) via a subframe bush having vibration-isolating rubber.
The subframe 10 is composed of a front member 11, a rear member 12, side members 13, etc.
The front member 11 is a beam-shaped member that is provided at the front end of the subframe 10 and arranged substantially along the vehicle width direction.
Both ends of the front member 11 are attached to the vehicle body via subframe bushings.
The rear member 12 is a beam-shaped member that is provided at the rear end of the subframe 10 and disposed substantially along the vehicle width direction.
Both ends of the rear member 12 are attached to the vehicle body via subframe bushings.
The side members 13 are beam-shaped members that connect a portion of the front member 11 near a side end portion and a portion of the rear member 12 near a side end portion substantially along the longitudinal direction of the vehicle.
The side members 13 are provided in a pair on the left and right sides and spaced apart in the vehicle width direction.
The side member 13 is provided with a bracket 14 which is a fastening portion to which a rubber bush 100 that supports the upper link 50 so that the upper link 50 can swing is fastened.
The bracket 14 cooperates with the rubber bushing 100 to form a support structure for the elastic bushing of this embodiment.
The detailed configuration of the fastening points in the bracket 14 (not shown in FIG. 1, see FIG. 3) will be described in detail later.

The housing 20 is a member (hub bearing housing, hub knuckle) that accommodates a hub bearing that rotatably supports a hub to which a wheel is attached.
The suspension device 1 supports a housing 20 relative to a subframe 10 so as to be able to stroke in the up and down direction (to be displaced up and down relative to the vehicle body) along a predetermined trajectory defined by suspension geometry.

The front lateral link 30 and the rear lateral link 40 are provided between the lower part of the side member 13 and the lower part of the housing 20 .
The front lateral link 30 and the rear lateral link 40 are disposed substantially along the vehicle width direction and spaced apart in the front-rear direction of the vehicle.
Both ends of the front lateral link 30 and the rear lateral link 40 are swingably connected to the side member 13 and the housing 20 via vibration-isolating rubber bushings.

The upper link 50 is provided between the bracket 14 provided on the upper part of the side member 13 and the upper part of the housing 20 .
The upper link 50 is disposed substantially along the vehicle width direction.
Both ends of the upper link 50 are swingably connected to the side member 13 and the housing 20 via vibration-isolating rubber bushes and ball joints, respectively.
The rubber bushing 100 provided at the end of the upper link 50 on the side member 13 side is an elastic bushing to which the support structure of this embodiment is applied.
The rubber bushing 100 is a cylindrical bushing having a central axis that is aligned substantially along the front-rear direction of the vehicle.
For example, a pair of rubber bushes 100 are provided spaced apart from each other in the front and rear.
The detailed configuration of the rubber bushing 100 and the fastening points between the rubber bushing 100 and the bracket 14 will be described in detail later.

The trailing link 60 is provided between the vicinity of the side end of the front member 11 and the lower part of the housing 20 .
The trailing link 60 is disposed substantially along the front-rear direction of the vehicle.
Both ends of the trailing link 60 are swingably connected to the front member 11 and the housing 20 via respective vibration-isolating rubber bushings.

The damper unit 70 is a unit made up of a damper that generates a damping force according to the expansion/contraction speed, and a coil spring (suspension spring) that generates a spring reaction force according to the amount of expansion/contraction.
The upper end of the damper unit 70 is attached to the vehicle body (not shown) via a top mount having anti-vibration rubber.
A lower end portion 71 of the damper unit 70 is attached to the middle portion of the rear lateral link 40 .
The lower end portion 71 is connected to the rear lateral link 40 via, for example, a ball joint (spherical bearing).

The stabilizer device 80 is an anti-roll device that generates a spring reaction force in a direction that reduces the difference between the left and right strokes when strokes in opposite directions (opposite phases) occur on the left and right sides of the suspension device 1.
The stabilizer device 80 has a stabilizer bar formed from spring steel, with a middle portion disposed substantially along the vehicle width direction, and both ends of the stabilizer bar are connected to the left and right rear lateral links 40 via links.

The rubber bush 100, which is an elastic bush provided at the connection between the inner end of the upper link 50 in the vehicle width direction and the bracket 14 provided on the side member 13 of the subframe 10, will be described below.
FIG. 2 is a diagram showing a configuration of an elastic bush in the embodiment.
FIG. 2(a) is a cross-sectional view of a rubber bush 100, which is an elastic bush of an embodiment, cut along a plane including the central axis of the elastic body 130, and FIG. 2(b) is a view taken along the arrows bb in FIG. 2(a).
FIG. 3 is a schematic cross-sectional view of a fastening portion between the elastic bush and the subframe in the embodiment.
3 shows a cross section taken along a plane that includes the central axis of the bolt B and is perpendicular to the central axis of the shaft 120. In FIG. 3, the right side shows the outer side in the vehicle width direction.

The rubber bushing 100 is configured to include an outer cylinder 110, a shaft 120, an elastic body 130, and the like.
The outer cylinder 110 is formed into a cylindrical shape from a material, such as steel, that has a higher hardness than the material of the elastic body 130 .
The outer peripheral surface of the outer cylinder 110 is fixed, for example by press fitting, to the inner diameter side of a cylindrical portion formed in the upper link 50, which is the supported member.

The shaft 120 is an axially shaped member that is inserted into the inner diameter side of the outer cylinder 110 .
The shaft 120 is a fastening member that is fastened to a bracket 14 of a subframe 10 that is provided on the vehicle body side.
The shaft 120 is formed from a material, such as steel, that has a higher hardness than the elastic body 130 .
The main body of the shaft 120 is formed in a cylindrical shape, and is arranged so as to be held concentrically with the outer cylinder 110 by the elastic body 130 in an unloaded state (when no external force is input).

The shaft 120 has a protrusion 121, a bolt seat portion 122, a convex curved surface portion 123, a bolt hole 124, etc.
The protrusions 121 are provided at both ends of the shaft 120 in the longitudinal direction (axial direction) and are portions (so-called ears) protruding from the end faces on both sides of the elastic body 130 .
The protrusion 121 is fastened to a bracket 14 formed on a side member 13 of the subframe 10 by mechanical fastening means (bolt B as an example in this embodiment).
In this embodiment, the protrusion 121 is adapted to be attached to the bracket 14 from above when mounted on the vehicle.

The bolt seat surface portion 122 is a surface portion formed on a portion of the protrusion 121 opposite to the bracket 14 side (for example, the upper portion in this embodiment).
The bolt bearing surface portion 122 is formed along a plane perpendicular to the axis of the bolt hole 124 .
The bolt seat portion 122 comes into contact with a washer portion of a washer-equipped bolt B (see FIG. 3 ) that fastens the protrusion portion 121 to the bracket 14 , and transmits the fastening load of the bolt B to the protrusion portion 121 .

The convex curved surface portion 123 is a surface portion formed on the bracket 14 side (lower side in this embodiment) of the protrusion 121, and is in surface contact with the concave curved surface portion 15 formed on the bracket 14, except for gaps that inevitably arise due to processing accuracy, etc.
The convex curved surface portion 123 is formed as an arc-shaped convex curved surface that is convex on the bracket 14 side (the lower surface side in FIGS. 2 and 3 ) when viewed from the central axial direction of the shaft 120 .
The center of this arc shape of the convex curved surface portion 123 is eccentrically positioned so as to be offset to the opposite side to the bracket 14 side (upper side in Figures 2 and 3) with respect to the central axis of the shaft 120 and the outer tube 110.
Furthermore, the radius of this arc can be, for example, approximately the same as the radius of the main body of the shaft 120 .
With the above-described configuration, the protrusion 121 has a substantially semicircular or D-shaped configuration when viewed in the axial direction of the shaft 120 .

The bolt holes 124 are for inserting bolts B (see FIG. 3), which are mechanical fastening means for fastening the protrusions 121 to the bracket 14 .
The bolt hole 124 is a circular through-hole having a central axis aligned along the normal direction of the bolt seat portion 122 .
The bolt holes 124 are arranged such that the central axis direction is substantially aligned with the vertical direction when the rubber bushing 100 is attached to a vehicle.

Elastic body 130 is made of a flexible elastic material such as a rubber material, and is provided between the inner peripheral surface of outer cylinder 110 and the outer peripheral surface of the main body of shaft 120 .
The inner peripheral surface of the outer cylinder 110 and the outer peripheral surface of the shaft 120 are each joined to an elastic body 130 by vulcanization adhesion or the like.
In the example shown in FIG. 2, the elastic body 130 has a uniform solid structure in both the axial and circumferential directions, but in order to adjust the rigidity, it is also possible to form a space in some parts as appropriate, or to provide a hard member (insert) in the material of the main body of the elastic body 130.
The outer peripheral surface of the elastic body 130 is connected via the outer cylinder 110 to the upper link 50 which is a supported member and a swingable member.

As shown in FIG. 3, the bracket 14 is formed with a concave curved surface portion 15 and a bolt hole 16 as fastening portions to which the rubber bushing 100 is fastened.
The concave surface portion 15 is formed as a concave surface having substantially the same curvature as the convex surface portion 123 so as to be in surface contact with the convex surface portion 123 of the shaft 120 .
The bolt hole 16 is a portion into which the tip of a bolt B, which is inserted through a bolt hole 124 of the shaft 120, is inserted and fastened.
The inner peripheral surface of the bolt hole 16 is formed with a female thread that is screwed to the bolt B and generates a bolt axial force.

The above-mentioned convex curved surface portion 123 and concave curved surface portion 15 are configured to be able to receive at least a portion of the load input from the upper link 50 while the vehicle is traveling, in a state that generates a normal force.
This point will be explained in detail below.
When the vehicle is traveling, the external force input from the upper link 50 to the outer cylinder 110 of the rubber bushing 100 is predominantly a tensile force or a compressive force acting on the upper link 50 as an axial force.
Here, the axial force of the upper link 50 means a tensile force or compressive force acting along a straight line connecting the center of swing on the subframe 10 side (vehicle body side) and the center of swing on the housing 20 side when viewed from the fore-and-aft direction of the vehicle (the central axial direction of the rubber bush 100).
The swing center on the subframe 10 side is the elastic center of the elastic body 130 , which in this embodiment substantially coincides with the central axis of the outer cylinder 110 and the elastic body 130 .

When the vehicle is traveling, the suspension device 1 strokes so that the housing 20 moves up and down relative to the subframe 10 as indicated by the dashed arrow in FIG.
In Figure 3, the direction in which the axial force of the upper link 50 acts when the suspension device 1 has stroked furthest toward the rebound side (extension side) is indicated by a straight line L1, and the direction in which the axial force of the upper link 50 acts when the suspension device 1 has stroked furthest toward the bump side (compression side) is indicated by a straight line L2.
The straight lines L1 and L2 are shown as straight lines passing through the centers of action of the respective axial forces.
The input direction from the upper link 50 to the rubber bushing 100 changes within an angular range θ between the straight lines L1 and L2 in accordance with the stroke of the suspension device 1.
Each axial force may be a tensile force or a compressive force, depending on the suspension geometry and the input to the tire contact point (ground load, cornering force, braking/driving force, etc.).

In the embodiment, at least a portion of the tensile force and compressive force in the direction along the straight line L1 can be received as a normal force in regions R1 and R2 of the contact surface between the convex curved surface portion 123 of the shaft 120 and the concave curved surface portion 15 of the bracket 14.
Furthermore, at least a part of the tensile force and compressive force in the direction along the straight line L2 can be received as a normal force in the regions R3 and R4 of the contact surface portion described above.
Regions R1 to R4, when viewed from the central axis direction of elastic body 130, include the points where straight line L1 or L2 intersects with convex curved surface portion 123 and concave curved surface portion 15, and are regions where the axial force of upper link 50 acts as a surface pressure.
Furthermore, even if the stroke amount of the suspension device 1 is in the intermediate region closest to the rebound side or the bump side, the direction of action of the axial force of the upper link 50 when viewed from the central axial direction of the elastic body 130 intersects with the convex curved portion 123 and the concave curved portion 15.
The curvature of the convex curved surface portion 123 and the central angle of the arc shape when viewed from the central axis direction of the elastic body 130 are set so as to satisfy the above-mentioned conditions.

The effects of this embodiment will be described in comparison with a comparative example of the present invention which will be described below.
In the comparative example, the same reference numerals are used for the parts common to the embodiment, and the description thereof is omitted, and the differences will be mainly described.
FIG. 4 is a diagram showing the configuration of an elastic bushing in a comparative example.
FIG. 4(a) is a cross-sectional view of a rubber bushing 100A, which is an elastic bushing of a comparative example, taken along a plane including the central axis, and FIG. 4(b) is a view taken along the arrows bb in FIG. 4(a).
The rubber bushing 100A of the comparative example has a flat surface portion 125 described below, instead of the convex curved surface portion 123 of the rubber bushing 100 of the embodiment.
The flat surface portion 125 is a surface portion that comes into contact with the bracket 14 and is formed as a flat surface parallel to the bolt seat surface portion 122 .
The flat surface portion 125 is fastened by a bolt B in a state of surface contact with a flat surface portion (not shown) formed on the bracket 14 .
In the comparative example described above, when an external force (axial force) acts from the upper link 50 to the rubber bush 100A along the direction of the straight lines L1, L2, or along a direction intermediate between the straight lines L1, L2, the external force acts in a direction that shifts the flat portion 125 in the planar direction relative to the flat portion of the bracket 14, which may result in a so-called fastening misalignment.
Furthermore, if such a fastening misalignment occurs, bending deformation occurs in the bolt B, which may further induce deformation of the bolt bearing surface portion 122.

In contrast, in the present embodiment, the axial forces (tensile force, compressive force) of the upper link 50 act to press the convex curved portion 123 and the concave curved portion 15 together with a normal force at a portion of the contact surface between them, so that the protrusion 121 is restrained against the bracket 14, preventing misalignment of the fastening.
Therefore, bending deformation of the bolt B and the associated deformation of the bolt bearing surface portion 122 can also be prevented.

As described above, according to this embodiment, the following effects can be obtained.
(1) The contact surface of the protrusion 121 with the bracket 14 is formed as the convex curved portion 123 which is an arc-shaped portion that is eccentric on the opposite side (upward) from the bracket 14 with respect to the central axis of the elastic body 130. This makes it possible to receive an external force (tensile force or compressive force) input from the upper link 50 along the radial direction of the elastic body 130 in a state that generates a normal force between the contact surfaces over a wide range of input angles.
As a result, it is possible to suppress shifting of the contact surface due to external forces, reduce the bending force on the bolt B, prevent bending deformation of the bolt B and buckling of the bolt seat portion 122, and improve the reliability of the fastening point.
In addition, it is possible to suppress the need to increase the fastening surface area and the bolt diameter in order to improve resistance to large external forces, and it is possible to reduce the size and weight of the support structure for the elastic bushing.
(2) When viewed from the direction of the central axis of the elastic body 130, when the upper link 50 is within a predetermined swing angle range θ, straight lines L1 and L2, which are in the same direction as the axial force direction input from the upper link 50 to the elastic body 130 and pass through the center of action of the axial force, or a straight line in an intermediate angle range between these two, intersect with the convex curved surface portion 123 of the protrusion 121.Therefore, when the axial force of the upper link 50 is input to the rubber bushing 100 as an external force, this input can be received in a state in which a normal force is reliably generated between the contact surfaces of the convex curved surface portion 123 of the protrusion 121 of the shaft 120 and the concave curved surface portion 15 of the bracket 14, thereby preventing shifting of the contact surfaces and deformation of the bolt B due to external force and improving the reliability of the fastening point.
(3) Since the above-mentioned straight lines L1, L2, etc. intersect with the convex curved portion 123 at two points, the above-mentioned effects can be obtained regardless of whether the axial force input from the upper link 50 is in the compressive direction or the tensile direction, and the reliability of the fastening points can be more reliably improved.

(Modification)
The present invention is not limited to the above-described embodiment, and various modifications and variations are possible, which are also within the technical scope of the present invention.
(1) The configuration of the support structure for the elastic bushing is not limited to the above-described embodiment and can be modified as appropriate.
For example, the shape, structure, material, arrangement, quantity, etc. of each part can be changed as appropriate.
(2) In the embodiment, the support structure for the elastic bush is provided, for example, at the vehicle body side (subframe side) end of the upper link of a double wishbone rear suspension. However, the present invention can be applied to other suspension devices including a front suspension, and there is no particular limitation on the type of link (arm) to which the present invention can be applied.
(3) The present invention is not limited to application to so-called suspension bushings provided at the ends of links (arms) in a suspension device, but can also be applied to elastic bushings provided in other locations.
For example, the present invention may be applied to engine mounts, transmission mounts, differential mounts, subframe bushings, and the like.
(4) In the embodiment, the convex curved surface portion and the concave curved surface portion have an arc-shaped cross-sectional shape when viewed from the central axial direction of the elastic body. However, this is not limited to this, and the curved surface may be formed into other shapes, such as an arc of an ellipse or an oval, or a parabola.
Furthermore, instead of such convex and concave curved surfaces, convex and concave surfaces formed by combining a plurality of flat surfaces, for example, may be used.
(5) In the above embodiment, the elastic body is made of a rubber-based material, but the elastic body is not limited to this and may be made of other elastic and flexible materials.
For example, a urethane-based material may be used.

REFERENCE SIGNS LIST 1 Suspension device 10 Subframe 11 Front member 12 Rear member 13 Side member 14 Bracket 15 Concave curved surface portion 16 Bolt hole 20 Housing 30 Front lateral link 40 Rear lateral link 50 Upper link 60 Trailing link 70 Damper unit 80 Stabilizer device 100 Rubber bush (embodiment) 100A Rubber bush (comparative example)
110 Outer cylinder 120 Shaft 121 Projection 122 Bolt seat 123 Convex curved surface 124 Bolt hole 125 Flat surface 130 Elastic body B Bolt L1 Direction of input from upper link (during rebound)
L2 Direction of input from upper link (when bumping)
R1 to R4: Area where the input direction and the contact surface intersect

Claims (4)

an elastic body formed in a cylindrical shape and having a supported member connected to an outer circumferential surface thereof;
and a fastening member that is held on the inner circumferential surface of the elastic body and fastened to the base .
The fastening member is fixed to the base by fastening a protruding portion protruding from an end face of the elastic body to a fastening portion formed on the base,
The contact surface of the protruding portion with the fastened portion is formed into a convex surface,
The contact surface of the fastened portion with the protruding portion is formed as a concave surface that comes into surface contact with the convex surface of the protruding portion.
A support structure for an elastic bush, comprising:
The convex surface is formed into a convex curved surface that is eccentric to the side opposite to the fastened portion with respect to the central axis when viewed from the central axis direction of the elastic body,
A support structure for an elastic bush, characterized in that the concave surface of the fastened portion is formed into a concave curved surface that is in surface contact with the convex surface of the protruding portion. the supported member is a swinging member that swings around a central axis of the elastic body within a predetermined angle range,
A support structure for an elastic bush as described in claim 1, characterized in that when viewed from the central axial direction of the elastic body, when the oscillating member is within the angular range, a straight line that is in the same direction as the input direction from the oscillating member to the elastic body and passes through the center of action of the input intersects with the convex surface of the protrusion. an elastic body formed in a cylindrical shape and having a supported member connected to an outer circumferential surface thereof;
and a fastening member that is held on the inner circumferential surface of the elastic body and fastened to the base .
The fastening member is fixed to the base by fastening a protruding portion protruding from an end face of the elastic body to a fastening portion formed on the base,
The contact surface of the protruding portion with the fastened portion is formed into a convex surface,
The contact surface of the fastened portion with the protruding portion is formed as a concave surface that comes into surface contact with the convex surface of the protruding portion.
A support structure for an elastic bush, comprising:
the supported member is a swinging member that swings around a central axis of the elastic body within a predetermined angle range,
A support structure for an elastic bush, characterized in that when viewed from the central axial direction of the elastic body, when the oscillating member is within the angular range, a straight line that is in the same direction as the input direction from the oscillating member to the elastic body and passes through the center of action of the input intersects with the convex surface of the protrusion. 4. The support structure for an elastic bush according to claim 2 , wherein the straight line intersects with the convex surface at two points.