Suspension system

Abstract

To achieve space-saving and cost reduction.SOLUTION: A suspension device includes: an inner member 11 attached to a vehicle body B; an outer member 12 which is provided on the outside YO beyond the inner member in a vehicle width direction Y to support an axle A; a first elastic member 13 for connecting the inner member and the outer member to each other in the vehicle width direction; and a second elastic member 14 for connecting the inner member and the outer member to each other in a vertical direction. The first elastic member includes an elastic plate 31 for generating elastic force and attenuation force at the time of elastic deformation, and a rigid plate 32 which is more rigid than the elastic plate, and the elastic plate and the rigid plate are laminated in the vehicle width direction. Further, the suspension device includes an attenuation force generating mechanism 16 for generating attenuation force in accompany with elastic deformation of the second elastic member in the vertical direction Z to impart resistance force to the elastic deformation of the second elastic member.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a suspension device. [Background technology]

[0002] 2. Description of the Related Art Conventionally, a suspension device including a coil spring, a shock absorber, and the like has been known, as disclosed in, for example, Patent Document 1 below. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Special Publication No. 2012-503570 Summary of the Invention [Problem to be solved by the invention]

[0004] However, the conventional suspension devices described above have a problem in that they take up a lot of space in small vehicles such as golf carts and buggies, making it difficult to ensure sufficient interior space.

[0005] The present invention has been made in consideration of the above circumstances, and has an object to provide a suspension device that can save space and reduce costs. [Means for solving the problem]

[0006] In order to solve the above problems and achieve the above object, the suspension device of the present invention comprises an inner member attached to a vehicle body, an outer member provided outboard of the inner member in the vehicle width direction and supporting an axle, a first elastic member connecting the inner member and the outer member to each other in the vehicle width direction, and a second elastic member connecting the inner member and the outer member to each other in the up-down direction, wherein the first elastic member comprises an elastic plate that generates an elastic force and a damping force upon elastic deformation, and a hard plate that is harder than the elastic plate, and is configured by stacking the elastic plate and the hard plate in the vehicle width direction, and comprises a damping force generating mechanism that generates a damping force in response to vertical elastic deformation of the second elastic member and provides resistance to the elastic deformation of the second elastic member.

[0007] The first elastic member, which connects the inner and outer members to each other in the vehicle width direction, is composed of an elastic plate and a hard plate stacked in the vehicle width direction.Therefore, even if conventional coil springs and shock absorbers are eliminated, elastic force and damping force can be generated by shearing deforming the elastic plate in the vertical direction in response to a vertical input load, and the rigidity of the suspension device in the vehicle width direction can be ensured. This makes it possible to eliminate the use of conventional coil springs and shock absorbers while ensuring rigidity in the vehicle width direction, thereby saving space and reducing costs. Since a second elastic member is provided that connects the inner member and the outer member to each other in the vertical direction, even if the conventional coil spring is eliminated, an elastic force can be reliably generated by elastically deforming the elastic plate and the second elastic member in response to an input load in the vertical direction. Since the damping force generating mechanism generates a damping force in response to the vertical elastic deformation of the second elastic member and provides resistance to the elastic deformation of the second elastic member, even if conventional shock absorbers are eliminated, by elastically deforming the second elastic member in response to a vertical input load and activating the damping force generating mechanism, it is possible to reliably generate a damping force of a magnitude that cannot be generated by the material properties of the elastic plate, the second elastic member, etc. alone.

[0008] The damping force generating mechanism may include a first liquid chamber formed in the second elastic member, a second liquid chamber having an elastic partition as part of the partition, and an orifice passage connecting the first liquid chamber and the second liquid chamber to each other.

[0009] Since the damping force generating mechanism is equipped with a first liquid chamber, a second liquid chamber, and an orifice passage, when an input load is applied in the vertical direction, the second elastic member and the elastic partition elastically deform, causing liquid to flow between the first liquid chamber and the second liquid chamber through the orifice passage, thereby enabling a damping force to be generated reliably with a simple configuration. Since the first fluid chamber is formed in the second elastic member, the bulkiness of the damping force generating mechanism can be suppressed.

[0010] The second elastic member may be formed in a cylindrical shape extending in the vertical direction, the inside of the second elastic member may be the first liquid chamber, and a plurality of ring bodies may be attached to the second elastic member at intervals in the vertical direction.

[0011] Since the second elastic member is fitted with a plurality of ring bodies spaced apart in the vertical direction, it becomes difficult for the second elastic member to deform radially outward in response to a vertical compressive load, making it possible to make the first liquid chamber more likely to undergo shrinking deformation, and liquid can reliably flow between the first and second liquid chambers through the orifice passage in response to a vertical input load. Since the first fluid chamber is located inside the cylindrical second elastic member, the bulkiness of the damping force generating mechanism can be reliably suppressed.

[0012] The orifice passage may include a valve chamber having a seating surface on a part of its inner surface, a valve body arranged so as to be movable away from the seating surface and biased toward the seating surface, and a first connecting hole and a second connecting hole formed in the valve body and the seating surface and communicating with each other.

[0013] The orifice passage includes a valve chamber having a seating surface, a first connecting hole in the valve body, and a second connecting hole in the seating surface. As the second elastic member and the elastic partition wall elastically deform in response to an input load in the vertical direction, liquid flows between the first liquid chamber and the second liquid chamber through the orifice passage, which includes the first connecting hole in the valve body and the second connecting hole in the seating surface, generating a damping force. When a load with large amplitude is applied in the vertical direction, the valve body moves away from the seating surface against the biasing force, the second connection hole in the seating surface is opened, and the liquid that attempts to flow into the valve chamber through the second connection hole is more likely to flow directly into the valve chamber without passing through the first connection hole in the valve body. This makes it possible to suppress the damping force that occurs when a load with large amplitude is applied in the vertical direction, and to suppress deterioration of the ride comfort at that time.

[0014] The elastic plate, the hard plate, the inner member, and the outer member each have a first mounting surface and a second mounting surface that face each other in the vehicle width direction and to which the first elastic member is attached, and are curved so as to present a protruding curve toward the inside in the vehicle width direction when viewed from the top-bottom direction, and the center of curvature of each of the elastic plate, the hard plate, the first mounting surface, and the second mounting surface may be located outward in the vehicle width direction from the equator of a tire mounted on the axle when viewed from the top-bottom direction.

[0015] The first elastic member that connects the first mounting surface of the inner member and the second mounting surface of the outer member to each other is composed of an elastic plate and a hard plate stacked in the vehicle width direction, and when viewed from the top-bottom direction, the elastic plate, the hard plate, the first mounting surface, and the second mounting surface are curved to present a protruding curve toward the inside in the vehicle width direction, and each center of curvature is located outside the equator of the tire in the vehicle width direction. Therefore, when an external force in the front-rear direction or the vehicle width direction is applied to the vehicle, the elastic plate undergoes shear deformation in the front-rear direction around the center of curvature when viewed from the top-bottom direction, and the outer member can rotate in the front-rear direction together with the axle around the center of curvature relative to the inner member. As a result, even if the conventional link mechanism is eliminated, when the above-mentioned external force is applied to the vehicle, it is possible to, for example, tilt the tires in the toe-in direction to stabilize the posture of the vehicle body. As a result, it is possible to eliminate the conventional link mechanism, thereby ensuring space saving and cost reduction.

[0016] The first elastic members may be provided in a pair, one above and one below, and provided at each position on either side of the axle in the vertical direction, and the elastic plate, the hard plate, the first mounting surface, and the second mounting surface may extend inward in the vehicle width direction as they move away from the axle in the vertical direction in a cross-sectional view along the vertical and vehicle width directions.

[0017] Since a pair of first elastic members, one above and one below, are provided at positions sandwiching the axle in the vertical direction, camber rigidity can be ensured. The elastic plate, the hard plate, the first mounting surface, and the second mounting surface extend inward in the vehicle width direction as they move away from the axle side in the up-down direction in the cross-sectional view. Therefore, it becomes easier to set the height position of the roll center in terms of geometry higher, and the amount of roll during cornering can be easily adjusted. Furthermore, when a vertical external force is applied to the vehicle, in the cross-sectional view, the elastic plate undergoes vertical shear deformation around the intersection of straight lines that pass through the center of each of the pair of first elastic members and extend in a direction perpendicular to the elastic plate and the hard plate, while the outer member rotates vertically together with the axle around the intersection relative to the inner member, making it easy to adjust the camber rigidity.

[0018] The inner member may be provided with a restricting member that restricts rearward movement of the outer member beyond a certain amount.

[0019] Since the inner member is provided with a restricting member that restricts rearward movement of the outer member beyond a certain amount, it is possible to prevent the outer member from being excessively displaced rearward together with the axle relative to the inner member when the tire goes over a protrusion during running or when braking. Effect of the Invention

[0020] According to the present invention, it is possible to achieve space saving and cost reduction. [Brief description of the drawings]

[0021] [Figure 1] 1 is a view of a suspension device shown as an embodiment, as viewed from the outside in a vehicle width direction. [Diagram 2] FIG. 2 is a cross-sectional view taken along line II-II of FIG. [Diagram 3] FIG. 2 is a cross-sectional view taken along line III-III in FIG. [Figure 4] FIG. 4 is a partially enlarged view of FIG. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Hereinafter, one embodiment of a suspension device will be described with reference to FIGS. The suspension device 1 includes an inner member 11, an outer member 12, a first elastic member 13, a second elastic member 14, a restricting member 15, and a damping force generating mechanism 16. The suspension device 1 is mounted on a small vehicle such as a golf cart or a buggy. When vibration is input to the suspension device 1, the inner member 11 and the outer member 12 undergo relative displacement while elastically deforming the first elastic member 13 and the second elastic member 14. The restricting member 15 does not necessarily have to be provided.

[0023] The inner member 11 is formed in a plate shape and is attached to the vehicle body B with its front and back surfaces facing the vehicle width direction Y. The inner member 11 is formed with an insertion hole 11a into which the axle A is inserted so as to penetrate in the vehicle width direction Y. The insertion hole 11a is provided in the center of the front and back surfaces of the inner member 11.

[0024] An axle A and a tire T mounted on the axle A are shown diagrammatically in FIGS. Hereinafter, in the suspension device 1, the side of the tire T along the vehicle width direction Y is referred to as the outer side YO of the vehicle width direction Y, and the opposite side of the tire T along the vehicle width direction Y is referred to as the inner side YI of the vehicle width direction Y.

[0025] The inner member 11 is provided with a first wall portion 22 and a second wall portion 23 . The first wall portion 22 protrudes from the rear end portion of the inner member 11 toward the outside YO in the vehicle width direction Y. The front and back surfaces of the first wall portion 22 face in the front-rear direction X. The second wall portion 23 protrudes from an upper end portion of the inner member 11 toward the outside YO in the vehicle width direction Y. The front and back surfaces of the second wall portion 23 face the up-down direction Z. The second wall portion 23 is provided in the center of the upper end portion of the inner member 11 in the front-rear direction X, and is located above the first wall portion 22.

[0026] The outer member 12 is provided on the outer side YO of the inner member 11 in the vehicle width direction Y. The outer member 12 is formed in a plate shape, with the front and back surfaces facing the vehicle width direction Y. The outer member 12 faces the inner member 11 in the vehicle width direction Y. The outer member 12 is located forward of the front surface of the first wall portion 22 and on the outer side YO in the vehicle width direction Y. The outer member 12 is formed with a support hole 12a that penetrates in the vehicle width direction Y and supports the axle A. The support hole 12a is disposed coaxially with the insertion hole 11a of the inner member 11. The inner diameter of the support hole 12a is smaller than the inner diameter of the insertion hole 11a.

[0027] The first elastic member 13 connects the inner member 11 and the outer member 12 to each other in the vehicle width direction Y. The first elastic member 13 includes an elastic plate 31 that generates an elastic force and a damping force when elastically deformed, and a hard plate 32 that is harder than the elastic plate 31, and is configured by stacking the elastic plate 31 and the hard plate 32 in the vehicle width direction Y. A plurality of elastic plates 31 and a plurality of hard plates 32 are provided, and are arranged alternately in the vehicle width direction Y. The elastic plates 31 are arranged in a substantially unloaded state in the vertical direction Z when the suspension device 1 is mounted on the vehicle.

[0028] The front and back surfaces of the elastic plate 31 and the hard plate 32 face the vehicle width direction Y. The elastic plate 31 is formed of, for example, a rubber material or a synthetic resin material, and the hard plate 32 is formed of, for example, a metal material or a synthetic resin material having a higher hardness than the material forming the elastic plate 31.

[0029] The elastic plate 31, the hard plate 32, the inner member 11, and the outer member 12 each have a first mounting surface 26 and a second mounting surface 27 which face each other in the vehicle width direction Y and to which the first elastic member 13 is attached, and are curved so as to present a protruding curve toward the inside YI of the vehicle width direction Y, as shown in Figure 2, when viewed from the vertical direction Z.

[0030] Here, the inner member 11 is formed with a rectangular parallelepiped inner protrusion 11b that protrudes toward the outer side YO in the vehicle width direction Y and extends in the front-rear direction X, and a first mounting surface 26 is formed on the surface of the inner protrusion 11b facing the outer side YO in the vehicle width direction Y. The inner protrusion 11b and the first mounting surface 26 are formed over the entire length of the inner member 11 in the front-rear direction X. As shown in FIG. 3, a pair of upper and lower inner protrusions 11b and first mounting surfaces 26 are provided, and are provided at positions sandwiching the axle A in the up-down direction Z. The pair of upper and lower inner protrusions 11b and first mounting surfaces 26 are provided at the same distance from the axle A in the up-down direction Z.

[0031] Further, the outer member 12 is formed with a rectangular parallelepiped outer protrusion 12b that protrudes toward the inner side YI of the vehicle width direction Y and extends in the front-rear direction X, and a second mounting surface 27 is formed on the surface of the outer protrusion 12b facing the inner side YI of the vehicle width direction Y. The outer protrusion 12b and the second mounting surface 27 are formed over the entire length of the outer member 12 in the front-rear direction X. The outer protrusion 12b and the second mounting surface 27 are provided in pairs at upper and lower positions, and are provided at positions sandwiching the axle A in the vertical direction Z. The pair of upper and lower outer protrusions 12b and the second mounting surface 27 are provided at the same distance from the axle A in the vertical direction Z. As shown in FIG. 2, at least the center portion of the second mounting surface 27 in the front-rear direction X is located on the inner side YI of the vehicle width direction Y than both ends of the first mounting surface 26 in the front-rear direction X.

[0032] The size of the outer protrusion 12b in the vehicle width direction Y decreases with increasing distance from the center along the front-rear direction X. Both end faces of the outer protrusion 12b in the front-rear direction X are flat surfaces extending in the up-down direction Z and the vehicle width direction Y. The size of the rear end face of the outer protrusion 12b in the vehicle width direction Y is larger than the size of the front end face of the outer protrusion 12b in the vehicle width direction Y. The rear end face of the outer protrusion 12b is located forward of the front surface of the first wall portion 22 and faces the front-rear direction X. The upper end face of the outer protrusion 12b is a flat surface extending in the front-rear direction X and the vehicle width direction Y. Of the pair of upper and lower outer protrusions 12b, the upper end face of the outer protrusion 12b located above is located below the lower surface of the second wall portion 23 and faces the lower surface in the up-down direction Z.

[0033] Here, the regulating member 15 is provided on the inner member 11 and regulates the rearward movement of the outer member 12 beyond a certain amount. The regulating member 15 is formed of, for example, a rubber material or a synthetic resin material, and is provided on the front surface of the first wall portion 22. The regulating member 15 is formed in a rectangular parallelepiped shape extending in the up-down direction Z. The regulating member 15 faces the rear end surface of the outer protrusion 12b in the front-rear direction X. As shown in FIG. 1, a pair of regulating members 15 are provided, one above the other. The regulating members 15 face each other in the front-rear direction X over the entire length of the rear end surface of the outer protrusion 12b in the up-down direction Z.

[0034] When viewed from the up-down direction Z, the centers of curvature of the elastic plate 31, the hard plate 32, the first mounting surface 26, and the second mounting surface 27 are located on the outer side YO in the vehicle width direction Y from the equator portion CL of the tire T. The centers of curvature are located rearward of the axle A. The position of the centers of curvature in the front-rear direction X relative to the axle A may be changed as appropriate. As shown in Fig. 2, in a cross-sectional view along the front-rear direction X and the vehicle width direction Y, the distance in the vehicle width direction Y between the first mounting surface 26 and the second mounting surface 27 is equal over the entire length in the front-rear direction X.

[0035] A pair of first elastic members 13 are provided, one above and one below, at each position sandwiching the axle A in the vertical direction Z. The first mounting surfaces 26 are provided at the upper and lower ends of the inner member 11, respectively, and the second mounting surfaces 27 are provided at both ends of the outer member 12 in the vertical direction Z.

[0036] 3, in a cross-sectional view along the vertical direction Z and the vehicle width direction Y, the elastic plate 31, the hard plate 32, the first mounting surface 26, and the second mounting surface 27 extend toward the inner side YI in the vehicle width direction Y as they move away from the axle A side in the vertical direction Z. As a result, in the cross-sectional view shown in FIG 3, the intersection of each straight line L that passes through the center of each of the pair of first elastic members 13 and extends in a direction perpendicular to the elastic plate 31 and the hard plate 32 is located on the inner side YI in the vehicle width direction Y than the inner member 11.

[0037] The second elastic member 14 is sandwiched in the vertical direction Z between the inner member 11 and the outer member 12. The second elastic member 14 connects the inner member 11 and the outer member 12 to each other in the vertical direction Z. The second elastic member 14 is supported by being sandwiched in the vertical direction Z between the lower surface of the second wall portion 23 and the upper end surface of the upper outer protrusion 12b of the pair of upper and lower outer protrusions 12b. The second elastic member 14 is compressively deformed in the vertical direction Z when the suspension device 1 is mounted on the vehicle.

[0038] The second elastic member 14 is formed in a cylindrical shape extending in the up-down direction Z. The second elastic member 14 is formed of, for example, a rubber material, a synthetic resin material, or the like. The second elastic member 14 is formed of a material that generates an elastic force and a damping force when elastically deformed. 2, the second elastic member 14 and the axle A are located at the same position in the front-rear direction X. The central axes of the second elastic member 14 and the axle A intersect with each other by design. The second elastic member 14 is provided at the center of the upper end surface of the upper outer protrusion 12b out of the pair of upper and lower outer protrusions 12b.

[0039] As shown in FIG. 4, a plurality of ring bodies 28 are mounted on the second elastic member 14 at intervals in the vertical direction Z. The ring bodies 28 are formed of, for example, a metal material. A plurality of annular protrusions 14a are formed on the outer peripheral surface of the second elastic member 14 at intervals in the vertical direction Z, protruding radially outward and continuously extending over the entire circumferential length. The ring bodies 28 are mounted on the outer peripheral surface of the second elastic member 14 at portions between adjacent annular protrusions 14a in the vertical direction Z. The interval between adjacent annular protrusions 14a in the vertical direction Z is equal to the wire diameter of the ring bodies 28. The annular protrusions 14a and the ring bodies 28 may not be provided on the outer peripheral surface of the second elastic member 14.

[0040] The second elastic member 14 is formed in a bottomed cylindrical shape. A cover plate 29 is fixed to the upper end surface of the second elastic member 14. The cover plate 29 is formed of, for example, a metal material. A mounting hole 29a is formed in the center of the cover plate 29, penetrating in the vertical direction Z and opening into the second elastic member 14. A female screw portion is formed on the inner peripheral surface of the upper portion of the mounting hole 29a. The mounting hole 29a and the second elastic member 14 are arranged coaxially with each other. The upper end surface of the second elastic member 14 is supported by the lower surface of the second wall portion 23 via the cover plate 29.

[0041] The damping force generating mechanism 16 generates a damping force in response to elastic deformation of the second elastic member 14 in the vertical direction Z, and applies resistance to the elastic deformation of the second elastic member 14. The damping force generating mechanism 16 generates a damping force larger than those of the first elastic member 13 and the second elastic member 14 when a load is input in the vertical direction Z.

[0042] The damping force generating mechanism 16 includes a first liquid chamber 33 formed in the second elastic member 14, a second liquid chamber 35 having an elastic partition 34 as part of the partition, and an orifice passage 36 connecting the first liquid chamber 33 and the second liquid chamber 35 to each other. The first fluid chamber 33 is located inside the bottomed cylindrical second elastic member 14. The second fluid chamber 35 is provided above the second wall portion 23. The orifice passage 36 passes through the cover plate 29 and the second wall portion 23 in the up-down direction Z.

[0043] The damping force generating mechanism 16 includes a cylindrical body 41 provided above the second wall portion 23, and a plug member 42 that connects the cylindrical body 41 and the second elastic member 14 to each other.

[0044] The cylindrical body 41 extends in the vertical direction Z. The upper end opening of the cylindrical body 41 is closed by the elastic partition wall 34 and the rigid partition wall 37. The inside of the cylindrical body 41 forms the second liquid chamber 35. The elastic partition wall 34 is formed of, for example, a rubber material or a synthetic resin material, and the rigid partition wall 37 is formed of, for example, a metal material or a synthetic resin material. The elastic partition wall 34 is formed in an annular shape, and the rigid partition wall 37 closes the inside of the elastic partition wall 34. The rigid partition wall 37 is formed in a topped cylindrical shape. The elastic partition wall 34 extends upward from the outer circumferential surface of the rigid partition wall 37 toward the outside in the radial direction. The cylindrical body 41, the elastic partition wall 34, and the rigid partition wall 37 are arranged coaxially with the second elastic member 14. The elastic partition 34 is provided in a state in which it is elastically deformed upward relative to the cylindrical body 41, and the insides of the first liquid chamber 33, the second liquid chamber 35, and the orifice passage 36 are pressurized by the restoring force of the elastic partition 34. This makes it difficult for cavitation to occur inside the first liquid chamber 33, the second liquid chamber 35, and the orifice passage 36. The cylindrical body 41 may be provided below the second wall portion 23, or may be attached to a mounting hole formed in the second wall portion 23.

[0045] The plug member 42 includes a main body tube 43 extending in the vertical direction Z and having an orifice passage 36 on its inside, and a flange portion 44 protruding radially outward from the outer circumferential surface of the main body tube 43 and extending continuously over the entire circumferential length.

[0046] The main body tube 43 penetrates the cover plate 29 and the second wall portion 23 in the vertical direction Z. The upper end of the main body tube 43 is inserted into the cylinder 41. The outer circumferential surface of the main body tube 43 is formed with a male screw portion screwed into a female screw portion formed on the inner circumferential surface of the upper part of the mounting hole 29a of the cover plate 29. The lower end of the outer circumferential surface of the main body tube 43, located below the male screw portion, is in liquid-tight contact with the inner circumferential surface of the mounting hole 29a of the cover plate 29. An O-ring is provided between the lower end of the outer circumferential surface of the main body tube 43 and the inner circumferential surface of the mounting hole 29a. The lower end of the main body tube 43 is integrally fitted into the mounting hole 29a and the upper end of the second elastic member 14. The flange portion 44 is fitted into the liquid chamber within the lower end portion of the cylindrical body 41. The lower end portion of the cylindrical body 41 is crimped. The lower surface of the inner periphery of the flange portion 44 abuts against the upper surface of the second wall portion 23.

[0047] Here, the orifice passage 36 includes a valve chamber 45 , a first connecting hole 48 and a second connecting hole 49 .

[0048] The valve chamber 45 has a seating surface 46 on a part of its inner surface, and a valve element 47 is accommodated in the valve chamber 45 so as to be separable from the seating surface 46 and is biased toward the seating surface 46 . The valve chamber 45 is a recess formed in the upper end surface of the main cylinder 43, and the seating surface 46 is the bottom surface of the recess. A support ring 51 is attached in the upper end of the recess. The support ring 51 is screwed into the upper end of the recess. The valve chamber 45 and the second fluid chamber 35 communicate with each other through the support ring 51.

[0049] The valve body 47 is formed in a cylindrical shape extending in the vertical direction Z. A protrusion 47a is formed at the lower end of the valve body 47, protruding radially outward and extending continuously over the entire circumferential length. The valve body 47 moves in the vertical direction Z while being spaced apart from a side surface of the inner surface of the valve chamber 45 that extends upward from the outer circumferential edge of the seating surface 46, and comes into contact with and separates from the seating surface 46.

[0050] A first connection hole 48 and a second connection hole 49 that communicate with each other are formed in the valve body 47 and the seating surface 46. The inner diameter of the first connection hole 48 is smaller than the inner diameter of the second connection hole 49. The inner diameter of the first connection hole 48 may be equal to or larger than the inner diameter of the second connection hole 49. The inner diameter of the second connection hole 49 is equal to the inner diameter of the support ring 51. The inner diameters of the second connection hole 49 and the support ring 51 may be different from each other. The first connection hole 48 is located inside the cylindrical valve body 47. The inner diameter of the lower end of the first connection hole 48 is smaller than the inner diameter of a portion located above the lower end. The upper end opening of the first connection hole 48 is located inside the valve chamber 45. The inside of the valve chamber 45 and the second connection hole 49 communicate with each other through the first connection hole 48.

[0051] The valve chamber 45 accommodates a biasing member 52 that biases the valve body 47 toward the seating surface 46. The biasing member 52 is, for example, a coil spring. The lower end of the biasing member 52 is supported on the upper surface of the protrusion 47a of the valve body 47. The upper end of the biasing member 52 is supported on the lower surface of the support ring 51. The upper end of the valve body 47 is spaced downward from the lower surface of the support ring 51.

[0052] As described above, according to the suspension device 1 of this embodiment, the first elastic member 13, which connects the inner member 11 and the outer member 12 to each other in the vehicle width direction Y, is composed of an elastic plate 31 and a hard plate 32 stacked in the vehicle width direction Y. Therefore, even if conventional coil springs and shock absorbers are eliminated, an elastic force and a damping force can be generated by shearing the elastic plate 31 in the vertical direction Z in response to an input load in the vertical direction Z, and the rigidity of the suspension device 1 in the vehicle width direction Y can be ensured. This makes it possible to eliminate the use of conventional coil springs and shock absorbers while ensuring rigidity in the vehicle width direction Y, thereby saving space and reducing costs.

[0053] Since the second elastic member 14 connects the inner member 11 and the outer member 12 to each other in the vertical direction Z, even if the conventional coil spring is eliminated, an elastic force can be reliably generated by elastically deforming the elastic plate 31 and the second elastic member 14 in response to an input load in the vertical direction Z.

[0054] Since the damping force generating mechanism 16 generates a damping force in response to the elastic deformation of the second elastic member 14 in the vertical direction Z and provides resistance to the elastic deformation of the second elastic member 14, even if conventional shock absorbers are eliminated, by elastically deforming the second elastic member 14 in response to an input load in the vertical direction Z and activating the damping force generating mechanism 16, it is possible to reliably generate a damping force of a magnitude that cannot be generated by the material properties of the elastic plate 31, the second elastic member 14, etc. alone.

[0055] Since the damping force generating mechanism 16 is equipped with a first liquid chamber 33, a second liquid chamber 35, and an orifice passage 36, when an input load is applied in the vertical direction Z, the second elastic member 14 and the elastic partition 34 elastically deform, causing liquid to flow between the first liquid chamber 33 and the second liquid chamber 35 through the orifice passage 36, thereby enabling a damping force to be generated reliably with a simple configuration. Since the first fluid chamber 33 is formed in the second elastic member 14, the bulkiness of the damping force generating mechanism 16 can be suppressed.

[0056] Since the second elastic member 14 is externally fitted with a plurality of ring bodies 28 spaced apart in the vertical direction Z, it becomes possible to make it difficult for the second elastic member 14 to deform radially outward in response to a compressive load in the vertical direction Z, thereby making it easier for the first liquid chamber 33 to deform in a reduced size, and therefore it is possible to reliably allow liquid to flow between the first liquid chamber 33 and the second liquid chamber 35 through the orifice passage 36 in response to an input load in the vertical direction Z. Since the first fluid chamber 33 is located inside the cylindrical second elastic member 14, the bulkiness of the damping force generating mechanism 16 can be reliably suppressed.

[0057] The orifice passage 36 is provided with a valve chamber 45 having a seating surface 46, a first connecting hole 48 of the valve body 47, and a second connecting hole 49 of the seating surface 46. Therefore, as the second elastic member 14 and the elastic partition 34 elastically deform in response to an input load in the vertical direction Z, liquid flows between the first liquid chamber 33 and the second liquid chamber 35 through the orifice passage 36, including the first connecting hole 48 of the valve body 47 and the second connecting hole 49 of the seating surface 46, generating a damping force.

[0058] When a load with large amplitude is input in the vertical direction Z, the valve body 47 moves away from the seating surface 46 against the biasing force of the biasing member 52, the second connection hole 49 of the seating surface 46 is opened, and the liquid attempting to flow into the valve chamber 45 through the second connection hole 49 tends to flow directly into the valve chamber 45 without passing through the first connection hole 48 of the valve body 47. Therefore, the damping force generated when a load with large amplitude is input in the vertical direction Z is suppressed, and deterioration of the ride comfort at that time can be suppressed.

[0059] The first elastic member 13, which connects the first mounting surface 26 of the inner member 11 and the second mounting surface 27 of the outer member 12 to each other, is composed of an elastic plate 31 and a hard plate 32 stacked in the vehicle width direction Y, and when viewed from the up-down direction Z, the elastic plate 31, the hard plate 32, the first mounting surface 26, and the second mounting surface 27 are curved to present a protruding curve toward the inside YI of the vehicle width direction Y, and each center of curvature is located on the outside YO in the vehicle width direction Y of the equator CL of the tire T.

[0060] Therefore, when an external force in the front-rear direction X or the vehicle width direction Y is applied to the vehicle, the elastic plate 31 undergoes shear deformation in the front-rear direction X about the center of curvature as viewed from the up-down direction Z, and the outer member 12 can rotate in the front-rear direction X about the center of curvature together with the axle A relative to the inner member 11. As a result, even if the conventional link mechanism is eliminated, when the above-mentioned external force is applied to the vehicle, it is possible to stabilize the posture of the vehicle body by tilting the tire T in the toe-in direction, for example, as shown by the two-dot chain line in Fig. 2. As a result, it is possible to eliminate the conventional link mechanism, thereby ensuring space saving and cost reduction.

[0061] Since a pair of first elastic members 13, one above and one below, are provided at positions sandwiching the axle A in the vertical direction Z, it is possible to ensure camber rigidity.

[0062] As shown in Figure 3, when viewed in a cross-sectional view along the vertical direction Z and the vehicle width direction Y, the elastic plate 31, the hard plate 32, the first mounting surface 26, and the second mounting surface 27 extend toward the inner side YI in the vehicle width direction Y as they move away from the axle A side in the vertical direction Z. Therefore, it becomes easier to set the height position of the roll center in terms of geometry higher, and the amount of roll during cornering can be easily adjusted. Furthermore, when an external force in the vertical direction Z is applied to the vehicle, in a cross-sectional view as shown in Figure 3, the elastic plate 31 shears in the vertical direction Z around the intersection of each straight line L that passes through the center of each of the pair of first elastic members 13 and extends in a direction perpendicular to the elastic plate 31 and the hard plate 32, while the outer member 12 rotates in the vertical direction Z together with the axle A relative to the inner member 11 around the intersection, as shown by the dotted line in Figure 3, making it possible to easily adjust the camber rigidity.

[0063] The inner member 11 is provided with a restricting member 15 that restricts the rearward movement of the outer member 12 beyond a certain amount, so that the outer member 12 can be prevented from being excessively displaced rearward together with the axle A relative to the inner member 11 when the tire T goes over a protrusion during running or when braking.

[0064] The technical scope of the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention.

[0065] For example, the first elastic member 13, the first mounting surface 26, and the second mounting surface 27 may be provided one by one. The elastic plate 31, the hard plate 32, the first mounting surface 26, and the second mounting surface 27 may extend straight in the vertical direction Z in a cross-sectional view along the vertical direction Z and the vehicle width direction Y. The second elastic member 14 may be formed of a material that does not generate a damping force when elastically deformed.

[0066] The elastic plate 31, the hard plate 32, the first mounting surface 26, and the second mounting surface 27 may extend straight in the front-rear direction X, for example, when viewed from the up-down direction Z. When viewed from the vertical direction Z, the centers of curvature of the elastic plate 31, the hard plate 32, the first mounting surface 26, and the second mounting surface 27 may be located on the equator portion CL of the tire T, or may be located inward YI in the vehicle width direction Y from the equator portion CL. The first liquid chamber 33 may be provided outside the second elastic member 14 . The orifice passage 36 does not have a valve chamber 45, and the valve body 47 may not be provided.

[0067] In addition, within the scope of the spirit of the present invention, it is possible to replace the components in the above-described embodiments with well-known components as appropriate, and the above-described embodiments and variations may be combined as appropriate. [Explanation of symbols]

[0068] 1 Suspension device 11 Inner member 12 Outer member 13 First elastic member 14 Second elastic member 15 Regulatory components 16 Damping force generation mechanism 26 First mounting surface 27 Second mounting surface 28 Ring body 31 Elastic plate 32 Hard plate 33 1st liquid chamber 34 Elastic bulkhead 35 2nd liquid chamber 36 Orifice Passage 45 Valve chamber 46 Seating surface 47 Valve body 48 First connection hole 49 Second connection hole A-axle B. Body CL equator T Tire X Anteroposterior direction Y Vehicle width direction Z vertical direction

Claims

1. An inner member that is attached to a vehicle body; an outer member provided outboard of the inner member in a vehicle width direction and supporting an axle; a first elastic member that connects the inner member and the outer member to each other in a vehicle width direction; a second elastic member that connects the inner member and the outer member to each other in the up-down direction, The first elastic member includes an elastic plate that generates an elastic force and a damping force when elastically deformed, and a hard plate that is harder than the elastic plate, and the elastic plate and the hard plate are laminated in the vehicle width direction, A suspension device comprising a damping force generating mechanism that generates a damping force in response to vertical elastic deformation of the second elastic member and applies resistance to the elastic deformation of the second elastic member.

2. 2. The suspension device according to claim 1, wherein the damping force generating mechanism comprises a first liquid chamber formed in the second elastic member, a second liquid chamber having an elastic partition as part of the partition, and an orifice passage connecting the first liquid chamber and the second liquid chamber to each other.

3. The second elastic member is formed in a cylindrical shape extending in the vertical direction, The inside of the second elastic member is the first liquid chamber, 3. The suspension device according to claim 2, wherein a plurality of ring bodies are mounted on the exterior of said second elastic member at intervals in the vertical direction.

4. The orifice passage is a valve chamber having a seating surface on a part of an inner surface thereof, the valve chamber accommodating a valve disc that is disposed so as to be separable from the seating surface and is biased toward the seating surface; 4. The suspension device according to claim 2, further comprising: a first connection hole and a second connection hole that are formed in the valve body and the seating surface and communicate with each other.

5. a first mounting surface and a second mounting surface, which face each other in the vehicle width direction and to which the first elastic member is attached, of each of the elastic plate, the hard plate, the inner member, and the outer member are curved so as to present a protruding curve toward the inside in the vehicle width direction when viewed from the top-bottom direction, 5. The suspension device according to claim 1, wherein, when viewed from the top-bottom direction, the centers of curvature of the elastic plate, the hard plate, the first mounting surface, and the second mounting surface are located outward in the vehicle width direction from an equator portion of a tire mounted on the axle.

6. The first elastic members are provided in a pair, one above the other, and are provided at positions sandwiching the axle in the vertical direction, 6. The suspension device according to claim 5, wherein the elastic plate, the hard plate, the first mounting surface, and the second mounting surface extend inward in the vehicle width direction as they move away from the axle side in the vertical direction in a cross-sectional view along the vertical direction and the vehicle width direction.

7. 7. The suspension device according to claim 1, wherein the inner member is provided with a restricting member that restricts rearward movement of the outer member beyond a certain amount.

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