JP2021109466A - Suspension device - Google Patents

Abstract

To provide a suspension device that is capable of improving comfort of drive in a vehicle and facilitates tuning of roll suppression force.SOLUTION: A suspension device S1 of the present invention includes: a spring member 1 for generating spring force in a direction of decreasing a displacement difference between a left wheel WL and a right wheel WR to the left wheel WL and the right wheel WR when there is a difference in a vertical displacement between the left wheel WL and the right wheel WR of a vehicle with respect a vehicle body B of the vehicle; and a damping force generation device F1 for making damping force act in parallel on the spring force in the direction of decreasing the displacement difference between the left wheel WL and the right wheel WR when there is a difference in vertical displacement between the left wheel WL and the right wheel WR of the vehicle with respect to the vehicle body B of the vehicle.SELECTED DRAWING: Figure 1

Description

The present invention relates to an improvement of a suspension device.

Conventionally, a suspension device for a vehicle such as an automobile is generally provided between a main damper, which is interposed between the vehicle body and wheels to suppress vibration of the vehicle body, and a suspension device between the vehicle body and wheels in parallel with the main damper. It is equipped with a suspension spring that elastically supports the vehicle body and realizes a good ride quality.

When the vehicle turns, the centrifugal force acting on the vehicle body causes the vehicle body to tilt to the opposite side of the turning center, but the main damper and suspension spring alone may not be sufficient to sufficiently suppress the roll of the vehicle body. Therefore, in addition to the above configuration, the suspension device is bridged between the left wheel arranged on the left side of the vehicle body and the right wheel arranged on the right side of the vehicle body, and the left wheel and the right wheel are displaced with respect to the vehicle body in opposite phases. In some cases, a stabilizer that exerts a spring force that suppresses the displacement may be provided.

In suspension devices with stabilizers, the spring force exerted by the stabilizer can suppress the roll of the vehicle body, but with the aim of further improving riding comfort, a suspension device has been developed that suppresses the roll of the vehicle body by providing a damper at one end of the stabilizer. (See, for example, Patent Document 1).

Japanese Patent No. 3624759

In the case of the conventional suspension device, since the damper is interposed between one end of the stabilizer and the wheel, the stabilizer and the damper are interposed between the left wheel and the right wheel in series.

Therefore, the force that suppresses the roll of the vehicle body (roll suppression force) exerted by the suspension device in which the damper is connected in series with the stabilizer is the roll suppression force exerted by the suspension device in which only the stabilizer is interposed between the left wheel and the right wheel. It will be less than the force.

Further, when the stabilizer and the damper are connected in series, the amount of twist of the stabilizer tends to be reduced by the amount of expansion and contraction of the damper, which promotes insufficient roll suppressing force. As described above, in the suspension device in which the stabilizer and the damper are interposed between the left wheel and the right wheel in series, the roll restraining force may be insufficient and the riding comfort may not be sufficiently improved.

Furthermore, since the stabilizer and damper are interposed between the left wheel and the right wheel in series, changing the characteristics of the damper has a great effect on the spring force exerted by the stabilizer, and changing the characteristics of the stabilizer causes the damper to move. It affects the damping force exerted. Therefore, there is also a problem that tuning of the roll suppressing force of the suspension device becomes very complicated.

Therefore, the present invention provides a suspension device that can improve the riding comfort in a vehicle and that the roll suppressing force can be easily tuned.

In order to solve the above-mentioned object, the suspension device of the present invention has the left wheel and the right wheel with respect to the left wheel and the right wheel when there is a difference in the vertical displacement of the left wheel and the right wheel of the vehicle with respect to the vehicle body of the vehicle. When there is a difference between the spring member that generates the spring force in the direction of reducing the displacement difference and the vertical displacement of the left and right wheels of the vehicle with respect to the vehicle body, the left and right wheels with respect to the left and right wheels. It is equipped with a damping force generator that acts in parallel with the spring force in the direction of reducing the displacement difference of the wheels. Therefore, in the suspension device, if there is a difference in the vertical displacement of the left wheel and the right wheel with respect to the vehicle body while the vehicle is running, the spring member and the damping force generator will move the left wheel and the right wheel with respect to the vehicle body with respect to the left wheel and the right wheel. The spring force and the damping force act independently in the direction of reducing the displacement difference of the wheels.

Further, the suspension device is a stabilizer formed of a U-shaped torsion bar in which one end of the spring member is connected to the left wheel and the other end is connected to the right wheel, and the damping force generator is lateral to the vehicle body. A U-shaped rod that is rotatably mounted along the line, a connecting rod that connects one end of the rod to one of the left and right wheels, and a damper that connects the other end of the rod to the other of the left and right wheels. You may have. According to the suspension device configured in this way, the suspension device can be realized by adding only the damping force generator to the vehicle equipped with the existing stabilizer.

Further, the suspension device includes a U-shaped rod in which a damping force generator is rotatably mounted along the lateral direction with respect to the vehicle body, a damper that connects one end of the rod to the left wheel, and the other end of the rod on the right. A left wheel side spring having a damper connected to the wheel and a spring member interposed between one end of the rod and the left wheel, and a right wheel side spring interposed between the other end of the rod and the right wheel. It may be composed of and. When the suspension device is configured in this way, the stabilizer is not required. Therefore, the spring member and the damping force generator may be incorporated in the existing vehicle instead of the stabilizer, and the mountability on the vehicle is improved.

The dampers in the suspension device include a cylinder, a piston that is movably inserted into the cylinder, a piston rod that is movably inserted into the cylinder and extends from one end of the piston and protrudes out of the cylinder, and inside the cylinder. It has a balance spring that exerts an urging force in the direction of invading the piston rod into the cylinder against the rod reaction force that causes the piston rod to move out of the cylinder due to the pressure of the cylinder, and the piston is positioned at the center of the stroke with respect to the cylinder. Then, the reaction force of the rod and the urging force of the balance spring may be balanced. When the suspension device is configured in this way, when the damper strokes near the center of the stroke, it is possible to suppress the damper from behaving as a spring, so that the damping force generating device affects the roll amount of the vehicle body controlled by the spring member. Since it becomes difficult to give, tuning becomes even easier. In addition, if a balance spring is provided, the piston is returned to the center of the stroke with respect to the cylinder regardless of whether the damper expands or contracts, so the damper always urges one of the left and right wheels to approach the vehicle body and the left wheel. There is also an advantage that it is difficult to apply an eccentric load to the left and right wheels because it is no longer urged to separate the other of the right wheel from the vehicle body.

The dampers in the suspension device include a cylinder, a piston that is movably inserted into the cylinder, and a piston rod that is movably inserted into the cylinder and extends from both ends of the piston so that both ends protrude from both ends of the cylinder. May be provided. According to the suspension device configured in this way, since the damper does not function as a spring at all, the damping force generator does not affect the roll amount of the vehicle body controlled by the spring member at all, and tuning becomes easier. There is an advantage that an unbalanced load is not applied to the left and right wheels regardless of the stroke position of the damper.

Further, the damper in the suspension device may have a damping force characteristic in which the damping force is saturated when the damper speed becomes equal to or higher than the first damper speed. According to the suspension device configured in this way, when the vehicle body rolls at a high roll rate, the damping force generated by the damping force generator becomes too high, and the roll rigidity of the vehicle body rapidly increases. On the contrary, there is no need to worry that the passengers of the vehicle will feel uncomfortable or uncomfortable and the ride quality will be impaired.

Further, the suspension device includes a left wheel side main damper interposed between the vehicle body and the left wheel and a right wheel side main damper interposed between the vehicle body and the right wheel, and the left wheel side main damper and the right The wheel-side main damper has a damping force characteristic with a break point where the damping force changes at the second damper speed, which is higher than the first damper speed, and the damping force of the damper when expanding and contracting at the first damper speed. May be set to be larger than the damping force of the left wheel side main damper and the right wheel side main damper when expanding and contracting at the first damper speed. According to the suspension device configured in this way, when a displacement difference occurs between the left wheel and the right wheel, the vibration of the vehicle body in the very low speed range that cannot be covered by the left wheel side main damper and the right wheel side main damper can be generated. It becomes possible to suppress it, and the riding comfort in the vehicle can be further improved.

Therefore, according to the suspension device of the present invention, it is possible to improve the riding comfort in the vehicle and to easily tune the roll suppressing force.

It is a perspective view of the suspension device in the 1st Embodiment of this invention. It is a side view of the suspension arm which connects a vehicle body and a wheel. It is sectional drawing of the damper in 1st example. It is a figure explaining the damping force characteristic of a damper. It is a figure explaining the damping force characteristic of a damper and a main damper. It is sectional drawing of the damper in the 2nd example. It is a perspective view of the suspension device in the 2nd Embodiment of this invention.

Hereinafter, the present invention will be described based on the embodiments shown in the figure. The configurations common to the suspension devices S1 and S2 of each embodiment described below are designated by the same reference numerals, and in order to avoid duplication of description, the suspension devices S1 of one embodiment have been described. The detailed description of the configuration will be omitted in the description of the suspension device S2 of another embodiment.

<First Embodiment>
As shown in FIG. 1, the suspension device S1 according to the first embodiment has a left wheel WL and a right wheel when there is a difference in vertical displacement between the left wheel WL and the right wheel WR of the vehicle with respect to the vehicle body B of the vehicle. The stabilizer 1 as a spring member that generates a spring force in the direction of reducing the displacement difference between the left wheel WL and the right wheel WR with respect to the WR, and the left wheel WL and the right wheel WR of the vehicle with respect to the vehicle body B are displaced in the vertical direction. It is provided with a damping force generator F1 that acts in parallel with the spring force a damping force in a direction for reducing the displacement difference between the left wheel WL and the right wheel WR with respect to the left wheel WL and the right wheel WR when there is a difference.

Further, in the present embodiment, in addition to the above configuration, the suspension device S1 includes a left wheel side main damper MDL and a left wheel side suspension spring SPL interposed between the vehicle body B and the left wheel WL, and the vehicle body B and the right wheel. It is equipped with a right wheel side main damper MDR and a right wheel side suspension spring SPR interposed between the WR and the WR.

Hereinafter, each part of the suspension device S1 will be described in detail. As shown in FIG. 2, the left wheel WL is rotatably mounted on a knuckle 2a connected to the tip of a suspension arm 2 oscillating in the vertical direction on the left side of the vehicle body B. Like the left wheel WL, the right wheel WR is rotatably mounted on the knuckle 3a connected to the tip of the suspension arm 3 which is vertically swingably attached to the right side of the vehicle body B. Therefore, the left wheel WL and the right wheel WR are attached so as to be movable in the vertical direction with respect to the vehicle body B.

The left wheel side main damper MDL is a telescopic type damper including a cylinder 4 connected to the knuckle 2a and a piston rod 5 connected to the vehicle body B and entering and exiting the cylinder 4. When the piston rod 5 moves relative to the axial direction and expands and contracts, it exerts a damping force to suppress the vibration of the vehicle body B. The left wheel side suspension spring SPL is a coil spring, which is mounted on the outer periphery of the left wheel side main damper MDL and is interposed between the cylinder 4 and the piston rod 5 to urge the left wheel side main damper MDL in the extension direction. is doing. When the left wheel side main damper MDL is interposed between the vehicle body B and the left wheel WL, the left wheel side suspension spring SPL is also interposed between the vehicle body B and the left wheel WL, so the vehicle body is driven by the spring force of the left wheel side suspension spring PSL. B is elastically supported.

Like the left wheel side main damper MDL, the right wheel side main damper MDR is also a telescopic type damper equipped with a cylinder 4 connected to the knuckle 2a and a piston rod 5 connected to the vehicle body B and entering and exiting the cylinder 4. When the piston rod 5 moves relative to the cylinder 4 in the axial direction, it exerts a damping force and suppresses the vibration of the vehicle body B. The right wheel side suspension spring SPR is also a coil spring, and is mounted on the outer periphery of the right wheel side main damper MDR and is interposed between the cylinder 4 and the piston rod 5 to extend the right wheel side main damper MDR in the extension direction. To urge. When the right wheel side main damper MDR is interposed between the vehicle body B and the right wheel WR, the right wheel side suspension spring SPR is also interposed between the vehicle body B and the right wheel WR, so the right wheel side suspension spring PSR The vehicle body B is elastically supported by the spring force of.

The spring member is the stabilizer 1 as described above. The stabilizer 1 is composed of a U-shaped torsion bar arranged along the lateral direction of the vehicle body B, and one end thereof is connected to a knuckle 2a that rotatably holds the left wheel WL via the left main damper MDL. The other end is connected to the knuckle 3a that rotatably holds the right wheel WR via the right main damper MDR. The center of the stabilizer 1 is rotatably mounted on the vehicle body B about the lateral direction of the vehicle body B. Then, the stabilizer 1 is twisted when the left wheel WL and the right wheel WR are displaced in the vertical direction in opposite phases with respect to the vehicle body B, and exerts a spring force that suppresses the displacement of the left wheel WL and the right wheel WR. For example, when the vehicle turns to the left and the vehicle body B tilts to the right due to centrifugal force, the left wheel WL separates from the vehicle body B and the right wheel WR approaches, the stabilizer 1 is twisted, so that the stabilizer 1 is twisted with respect to the left wheel WL. A spring force in the direction of approaching the vehicle body B is applied, and a spring force in the direction of separating from the vehicle body B is applied to the right wheel WR. In this way, the stabilizer 1 exerts a spring force that suppresses the roll of the vehicle body B when the vehicle body B tilts due to the turning of the vehicle or the like. Further, even if the displacement directions of the left wheel WL and the right wheel WR with respect to the vehicle body B are the same, if there is a difference in the displacement amount, the stabilizer 1 is twisted, so that the displacement difference between the left wheel WL and the right wheel WR is reduced. A spring force is applied to the left wheel WL and the right wheel WR so as to do so. On the other hand, when the left wheel WL and the right wheel WR are displaced in the vertical direction in the same phase with respect to the vehicle body B, the stabilizer 1 does not exert a spring force for suppressing the displacement of the left wheel WL and the right wheel WR because they are not twisted. .. As described above, the stabilizer 1 exerts a spring force on the left wheel WL and the right wheel WR in the direction of reducing the displacement difference only when there is a difference in the vertical displacements of the left wheel WL and the right wheel WR with respect to the vehicle body B. Let me.

Subsequently, in the present embodiment, the damping force generator F1 connects a U-shaped rod 6 rotatably mounted with respect to the vehicle body B in the lateral direction and one end of the rod 6 to the left wheel WL. It includes a connecting rod 7 and a damper 8 that connects the other end of the rod 6 to the other end of the right wheel WR.

The rod 6 has a U shape, and the center of the rod 6 is rotatably mounted on the vehicle body B around the axis in the lateral direction of the vehicle body B. The setting of the moment of inertia of area and the material of the rod 6 are selected so that the rod 6 has high rigidity and twists to a torque load as compared with the stabilizer 1.

One end of the connecting rod 7 is rotatably connected to a bracket 4a provided in the middle of the cylinder 4 of the left wheel side main damper MDL, and the other end is fixedly connected to one end of the rod 6. Further, the material for setting the moment of inertia of area and the material of the connecting rod 7 are selected so that the connecting rod 7 has high rigidity and the bending is extremely small with respect to the load of the axial force. Further, one end of the damper 8 is rotatably connected to a bracket 4a provided in the middle of the cylinder of the right wheel side main damper MDR, and the other end is fixedly connected to the other end of the rod 6. The cylinder 4 of the left wheel side main damper MDL is connected to the knuckle 2a that rotatably holds the left wheel WL, and the connecting rod 7 is connected to the left wheel WL via the cylinder 4 of the left wheel side main damper MDL. It may be directly connected to the knuckle 2a holding the left wheel WL. Further, the cylinder 4 of the right wheel side main damper MDR is connected to the knuckle 2a that rotatably holds the right wheel WR, and the damper 8 is connected to the right wheel WR via the cylinder 4 of the right wheel side main damper MDR. Although it is connected, it may be directly connected to the knuckle 2a holding the right wheel WR. One end of the rod 6 may be connected to the right wheel WR with the connecting rod 7, and the other end of the rod 6 may be connected to the left wheel WL with the damper 8. Further, regarding the damper 8, the cylinder 10 may be connected to the left wheel WL or the right wheel WR side, and the piston rod 12 may be connected to the rod 6 side.

In the present embodiment, as shown in FIG. 3, the damper 8 includes a cylinder 10, a piston 11 movably inserted into the cylinder 10, and one end of the piston 11 movably inserted into the cylinder 10. A piston rod 12 extending from the cylinder 10 and projecting out of the cylinder 10 and a balance spring 13 are provided.

One end of the cylinder 10 is closed by a cap 14 provided with a connecting metal fitting 14a connected to the rod 6, and the other end of the cylinder 10 slides on the outer periphery of the piston rod 12 which is annular and is inserted into the inner circumference. It is blocked by the rod guide 15 in contact with the rod guide 15. A free piston 16 is slidably inserted into the cylinder 10, and inside the cylinder 10, hydraulic oil is placed in the air chamber G on which gas is sealed on the cap 14 side by the free piston 16 and on the rod guide 15 side. It is partitioned into a liquid chamber to be filled with. Further, a piston 11 is slidably inserted into the cylinder 10, and the liquid chamber in the cylinder 10 is divided into an extension side chamber R1 and a compression side chamber R2 by the piston 11. The air chamber G is filled with gas so that the pressure inside the air chamber G becomes a predetermined pressure equal to or higher than the atmospheric pressure even when the damper 8 is fully extended, and a damping force can be exerted even during contraction. It has become like. Further, the liquid chamber may be filled with a liquid other than hydraulic oil.

The piston 11 is provided with an extension side passage 11a and a compression side passage 11b that communicate the extension side chamber R1 and the compression side chamber R2. In the present embodiment, the extension side passage 11a is provided with the orifice 11c, the check valve 11d, and the relief valve 11e in parallel, and the compression side passage 11b is provided with the orifice 11f, the check valve 11g, and the relief valve. 11h is provided. The relief valve 11e opens the valve when the pressure of the extension side chamber R1 reaches the pressure of the compression side chamber R2 and the differential pressure between the two reaches the valve opening pressure, and allows the hydraulic oil of the extension side chamber R1 to move to the compression side chamber R2. .. The check valve 11d allows the hydraulic oil in the extension side chamber R1 to move to the compression side chamber R2 and prevents the hydraulic oil from moving in the opposite direction. The other relief valve 11h opens when the pressure in the compression side chamber R2 reaches the pressure in the extension side chamber R1 and the differential pressure between the two reaches the valve opening pressure, so that the hydraulic oil in the compression side chamber R2 moves to the extension side chamber R1. Tolerate. The check valve 11g allows the hydraulic oil in the compression side chamber R2 to move to the extension side chamber R1 and prevents the hydraulic oil from moving in the opposite direction.

When the damper 8 extends and the piston 11 moves upward in FIG. 3 with respect to the cylinder 10, the extension side chamber R1 is compressed and the compression side chamber R2 is expanded, so that the pressure in the extension side chamber R1 rises and the compression side chamber R1 rises. The pressure of R2 decreases. In this case, when the damper speed, which is the expansion / contraction speed of the damper 8, is low, the differential pressure between the pressure of the extension side chamber R1 and the pressure of the compression side chamber R2 does not reach the valve opening pressure of the relief valve 11e, so that the hydraulic oil is only the orifice 11c. To move from the extension side chamber R1 to the compression side chamber R2. Therefore, in this case, in the damper 8, as shown by the line X1 in FIG. 4, the orifice 11c gives resistance to the flow of hydraulic oil and exerts a damping force. On the other hand, when the damper speed at the time of extension of the damper 8 becomes the first damper speed V1 or more, the differential pressure between the pressure of the extension side chamber R1 and the pressure of the compression side chamber R2 reaches the valve opening pressure of the relief valve 11e, and the relief valve 11e opens. The valve and hydraulic oil pass not only through the orifice 11c but also through the relief valve 11e and move from the extension side chamber R1 to the compression side chamber R2. Therefore, when the damper 8 is extended, the relief valve 11e opens when the damper speed becomes equal to or higher than the first damper speed V1, and therefore, as shown by the line Y1 in FIG. 4, it attenuates even if the damper speed increases. The force is less likely to increase, and the damping force characteristic of the damper 8 shows a characteristic that the damping force reaches a plateau and saturates when the damper speed becomes the first damper speed V1 or higher.

When the damper 8 is extended, the piston rod 12 retracts from the cylinder 10, and the volume of the exit of the piston rod 12 is such that the free piston 16 moves upward in FIG. 3 in the cylinder 10 to expand the air chamber G. Will be compensated.

When the damper 8 contracts and the piston 11 moves downward in FIG. 3 with respect to the cylinder 10, the compression side chamber R2 is compressed and the extension side chamber R1 is expanded, so that the pressure in the compression side chamber R2 rises and the extension side chamber R2. The pressure of R1 decreases. In this case, when the damper speed is low, the differential pressure between the pressure of the compression side chamber R2 and the pressure of the extension side chamber R1 does not reach the valve opening pressure of the relief valve 11h, so that the hydraulic oil passes only through the orifice 11f and the compression side chamber R2. To the extension side chamber R1. Therefore, in this case, as shown by the line X2 in FIG. 4, the orifice 11f exerts a damping force by giving resistance to the flow of hydraulic oil in the damper 8. On the other hand, when the damper speed at the time of contraction of the damper 8 becomes the first damper speed V1 or more, the differential pressure between the pressure of the compression side chamber R2 and the pressure of the extension side chamber R1 reaches the valve opening pressure of the relief valve 11h, and the relief valve 11h opens. The valve and hydraulic oil pass not only through the orifice 11f but also through the relief valve 11h and move from the compression side chamber R2 to the extension side chamber R1. Therefore, when the damper speed is contracted, the relief valve 11h opens when the damper speed becomes equal to or higher than the first damper speed V1. Therefore, as shown by the line Y2 in FIG. The force is less likely to increase, and the damping force characteristic of the damper 8 shows a characteristic that the damping force reaches a plateau and saturates when the damper speed becomes the first damper speed V1 or higher.

When the damper 8 contracts, the piston rod 12 invades into the cylinder 10. The volume of the invading piston rod 12 is such that the free piston 16 moves downward in FIG. 3 and the air chamber G is reduced. Will be compensated. In the damper 8 of the present embodiment, the volume of the piston rod 12 entering and exiting the cylinder 10 is compensated by the expansion and contraction of the air chamber G, but the damper 8 has a volume outside the cylinder 10 instead of the air chamber G. It may be set in a so-called return cylinder type damper provided with a reservoir for compensation.

In the damper 8 configured in this way, the piston rod 12 is a single rod type that is arranged only in the extension side chamber R1, and the pressure receiving area that receives the pressure of the extension side chamber R1 of the piston 11 is that of the piston 11. It is smaller than the pressure receiving area that receives the pressure of the compression side chamber R2. Therefore, a damping force is generated by the orifice 11c and the relief valve 11e during the extension stroke of the damper 8, and a damping force is generated by the orifice 11f and the relief valve 11h during the contraction stroke of the damper 8. The damping force and the damping force on the compression side can be set independently, and the damping force characteristics are the same regardless of whether the damper 8 expands or contracts.

Further, the inside of the cylinder 10 is pressurized to the atmospheric pressure or higher by the air chamber G formed in the cylinder 10. Then, as described above, the pressure receiving area that receives the pressure of the extension side chamber R1 of the piston 11 is smaller than the pressure receiving area that receives the pressure of the compression side chamber R2 of the piston 11. Therefore, a rod reaction force that tries to push the piston rod 12 out of the cylinder 10 by the pressure in the cylinder 10 always acts on the piston 11.

The balance spring 13 is a coil spring, one end of which is fixed to the rod guide 15, and the other end of which faces the piston 11. When the piston 11 is arranged at the center of the stroke with respect to the cylinder 10, the balance spring 13 abuts on the piston 11 and exerts an urging force that opposes the rod reaction force and balances with the rod reaction force. When the balance spring 13 is provided in this way, when the piston 11 is arranged at the center of the stroke with respect to the cylinder 10, the rod reaction force and the urging force of the balance spring 13 are balanced, and the damper 8 does not extend or contract. It becomes.

In the damping force generator F1 configured in this way, when the left wheel WL and the right wheel WR are displaced in the vertical direction in opposite phases with respect to the vehicle body B, the relative displacement of the left wheel WL and the right wheel WR in the vertical direction is the rod 6. It is transmitted to the damper 8 via the connecting rod 7, and the damper 8 expands and contracts to exert a damping force. Therefore, the damping force generator F1 exerts a damping force that suppresses the displacement of the left wheel WL and the right wheel WR with respect to the vehicle body B when the left wheel WL and the right wheel WR are displaced in the vertical direction in opposite phases with respect to the vehicle body B. Since the rod 6 and the connecting rod 7 have high rigidity with little twisting or bending with respect to a force load, the damper 8 does not significantly attenuate the relative displacement of the left wheel WL and the right wheel WR in the vertical direction. Can be transmitted to.

Further, in the damping force generator F1, even if the displacement directions of the left wheel WL and the right wheel WR with respect to the vehicle body B are the same, the damper 8 expands and contracts when there is a difference in the displacement amount, so that the left wheel WL and the right wheel WR A damping force is applied in the direction of reducing the displacement difference between the two vehicles. On the other hand, in the damping force generator F1, when the left wheel WL and the right wheel WR are displaced in the vertical direction in the same phase with respect to the vehicle body B, the left wheel WL and the right wheel WR are not relatively displaced and the damper 8 is not expanded or contracted. It does not exert a damping force in the direction of reducing the displacement difference between the left wheel WL and the right wheel WR. In this way, the damping force generator F1 attenuates in the direction of reducing the displacement difference between the left wheel WL and the right wheel WR only when there is a difference in the vertical displacement of the left wheel WL and the right wheel WR with respect to the vehicle body B. Apply force. Further, since the damping force generator F1 is interposed between the left wheel WL and the right wheel WR in parallel with the stabilizer 1, the damping force generator F1 is damped in parallel with the spring force of the stabilizer 1 with respect to the left wheel WL and the right wheel WR. Apply force.

As described above, the suspension device S1 of the present invention has a left wheel WL with respect to the left wheel WL and a right wheel WR when there is a difference in vertical displacement between the left wheel WL and the right wheel WR of the vehicle with respect to the vehicle body B of the vehicle. When there is a difference in the vertical displacement of the left wheel WL and the right wheel WR of the vehicle with respect to the body B of the vehicle and the stabilizer (spring member) 1 that generates a spring force in the direction of reducing the displacement difference between the right wheel WR and the right wheel WR. It is provided with a damping force generator F1 that acts in parallel with the spring force in a direction of reducing the displacement difference between the left wheel WL and the right wheel WR with respect to the left wheel WL and the right wheel WR. Therefore, in the suspension device S1, if there is a difference in the vertical displacement of the left wheel WL and the right wheel WR with respect to the vehicle body B while the vehicle is running, the stabilizer 1 as a spring member and the damping force generator F1 become the left wheel WL. The spring force and the damping force are acted separately and independently on the right wheel WR in the direction of reducing the displacement difference between the left wheel WL and the right wheel WR with respect to the vehicle body B.

The stabilizer 1 as a spring member generates a spring force according to the displacement difference between the left wheel WL and the right wheel WR in the vertical direction with respect to the vehicle body B, and the damping force generator F1 generates a spring force in the vertical direction of the left wheel WL and the right wheel WR with respect to the vehicle body B. When the displacement difference is generated, a damping force is generated in the direction of reducing the displacement difference according to the relative speed of the left wheel WL and the right wheel WR.

Therefore, in the suspension device S1 configured in this way, the roll suppressing force is exerted by the spring force exerted by the stabilizer (spring member) 1 with respect to the roll amount of the car body B, and is damped depending on the roll rate of the car body B. The force generator F1 can exert a damping force to suppress the roll of the vehicle body B. In the suspension device S1, the stabilizer 1 as a spring member and the damping force generator F1 are interposed between the left wheel WL and the right wheel WR in parallel, so that the roll exerted by the stabilizer (spring member) 1 is exhibited. The damping force generator F1 does not reduce the restraining force, there is no concern that the roll restraining force becomes insufficient, and the riding comfort in the vehicle can be improved.

Further, in the suspension device S1, since the stabilizer 1 as a spring member and the damping force generator F1 are interposed between the left wheel WL and the right wheel WR in parallel, the stabilizer (spring member) 1 and the damping force are generated. Since the device F1 has a considerable influence on the characteristics of the other party, tuning of the stabilizer (spring member) 1 and the damping force generator F1 becomes very easy.

From the above, according to the suspension device S1 of the present invention, it is possible to improve the riding comfort in the vehicle and facilitate the tuning of the roll suppressing force.

As can be understood from the above, in the suspension device S1, the stabilizer (spring member) 1 and the damping force generator F1 need only be interposed between the left wheel WL and the right wheel WR in parallel. Therefore, the specific configuration of the suspension device S1 is not limited to the specific configuration described above, but in the suspension device S1 of the present embodiment, one end is connected to the left wheel WL and the other end is connected to the right wheel WR. A stabilizer 1 formed of a U-shaped torsion bar, which is a U-shaped rod 6 to which a damping force generator F1 is rotatably mounted along a lateral direction with respect to a vehicle body, and one end of the rod 6. It has a connecting rod 7 that connects to one of the left wheel WL and the right wheel WR, and a damper 8 that connects the other end of the rod 6 to the other of the left wheel WL and the right wheel WR. When the suspension device S1 is configured in this way, the suspension device S1 can be realized by adding only the damping force generator F1 to the vehicle equipped with the existing stabilizer.

Further, in the suspension device S1 of the present embodiment, the damper 8 in the damping force generating device F1 is movably inserted into the cylinder 10, the piston 11 movably inserted into the cylinder 10, and the cylinder 10. The piston rod 12 is inserted and extends from one end of the piston 11 and protrudes to the outside of the cylinder 10. The piston rod 12 is cylinderd against the rod reaction force that causes the piston rod 12 to move out of the cylinder 10 due to the pressure inside the cylinder 10. It has a balance spring 13 that exerts an urging force in the direction of entering the cylinder 10, and when the piston 11 is located at the center of the stroke with respect to the cylinder 10, the rod reaction force and the urging force of the balance spring 13 are balanced. There is. When the suspension device S1 is configured in this way, when the damper 8 strokes near the center of the stroke, it is possible to suppress the damper 8 from acting as a spring, so that the roll of the vehicle body B controlled by the stabilizer (spring member) 1 Since the damping force generator F1 is less likely to affect the amount, tuning becomes easier. Further, when the balance spring 13 is provided, the piston 11 is returned to the center of the stroke with respect to the cylinder 10 regardless of whether the damper 8 expands or contracts, so that the damper 8 always approaches one of the left wheel WL and the right wheel WR to the vehicle body B. There is also an advantage that it is difficult to apply an eccentric load to the left wheel WL and the right wheel WR because it is not urged in the direction of urging the left wheel WL and the right wheel WR in the direction of separating the other from the vehicle body B.

Further, in the suspension device S1 of the present embodiment, the damper 8 has a damping force characteristic in which the damping force is saturated when the damper speed becomes the first damper speed V1 or more. If the damper 8 has a damping force characteristic that saturates the damping force in this way, the damping force generated by the damping force generator F1 becomes too high when the vehicle body B rolls at a high roll rate. There is no need to worry that the roll rigidity of the vehicle body B will suddenly increase, which will make the passengers of the vehicle feel uncomfortable or uncomfortable and impair the riding comfort. As described above, the damping force characteristic of the damper 8 is preferably a damping force characteristic in which the damping force is saturated when the damper speed becomes the first damper speed V1 or higher. However, the suspension device S1 of the present invention is a stabilizer. Since the desired effect can be achieved by interposing the (spring member) 1 and the damping force generator F1 in parallel between the left wheel WL and the right wheel WR, the damping force characteristic of the damper 8 is based on this. Naturally, it is not limited.

As a result of research, the inventors have found that the first damper speed V1 can improve the riding comfort in a vehicle when it is set to 0.02 m / sec or less. The left wheel side main damper MDL and the right wheel side main damper MDR exert a large damping force when expanding and contracting at a very low speed of 0.02 m / sec or less, which makes the ride harder and gives the passengers a feeling of harshness and busyness. Since it is perceived, it is necessary to make the damping force very small.

Therefore, when the damper speed of the damper 8 reaches the first damper speed V1 set to 0.02 m / sec or less, the damping force close to the maximum damping force is exhibited, and the left wheel WL and the right wheel WR When there is a displacement difference between the two, it is possible to suppress the vibration of the vehicle body B in the very low speed range that cannot be covered by the left wheel side main damper MDL and the right wheel side main damper MDR, further improving the riding comfort in the vehicle. can.

Further, the optimum value of the maximum damping force generated by the damper 8 changes according to the vehicle weight, and the larger the mass, the larger the value is set. However, it is preferable to set it to 100 N or less, for example, the vehicle weight. If the vehicle is about 1.5t, the riding comfort in the vehicle can be improved by setting it to about 40N-60N. It has been found that it is preferable that the left wheel side main damper MDL and the right wheel side main damper MDR are smaller than the maximum damping force generated in terms of improving riding comfort.

Furthermore, as a result of research, the inventors have found that between the damping force characteristics of the left wheel side main damper MDL and the right wheel side main damper MDR and the damping force characteristics of the damper 8, as shown in FIG. We learned that the ride quality can be improved if the relationship is established. Specifically, the left wheel side main damper MDL and the right wheel side main damper MDR have a damping force characteristic having a bending point where the damping force changes at the second damper speed V2 in which the damper speed is higher than the first damper speed. ing. The damping force of the damper 8 when expanding and contracting at the first damper speed V1 is set to be larger than the damping force of the left wheel side main damper MDL and the right wheel side main damper MDR when expanding and contracting at the first damper speed V1. There is.

In order to realize the damping force characteristic with a bending point where the damping force changes, generally, an orifice and a leaf valve are provided on the left wheel side main damper MDL and the right wheel side main damper MDR, and the orifice characteristic is bent to the valve characteristic. It may be set so as to switch at a point. As shown in FIG. 5, the damping force characteristics of the left wheel side main damper MDL and the right wheel side main damper MDR have a damping force proportional to the square of the damper speed until the second damper speed V2 is reached. The orifice characteristic becomes large, and when the second damper speed V2 or more becomes, the damping force becomes large in proportion to the damper speed, and the characteristic changes at the break point Z in the figure. A damper having such a damping force characteristic is generally incorporated in a vehicle suspension, but has a damping force characteristic that saturates at a damper speed of a first damper speed V1 or higher, which is lower than the second damper speed V2. By using it in combination with the left wheel side main damper MDL that expands and contracts at the same speed when expanding and contracting at the first damper speed V1 and the damper 8 that exerts a larger damping force than the right wheel side main damper MDR, it becomes a left wheel WL. When there is a displacement difference with the right wheel WR, it is possible to suppress the vibration of the vehicle body B in the very low speed range that cannot be covered by the left wheel side main damper MDL and the right wheel side main damper MDR, and it is possible to ride comfort in the vehicle. Can be further improved. In order to realize the damping force characteristic having a bending point where the damping force changes at the second damper speed V2, it is easy to provide an orifice and a leaf valve on the left wheel side main damper MDL and the right wheel side main damper MDR. Not limited to this, a choke may be used instead of the orifice, a relief valve may be used instead of the leaf valve, or a variable damping valve may be provided to realize the damping force characteristic. ..

The damper 8 is a single-rod type damper as described above, but as shown in FIG. 6, the damper 8 includes a cylinder 20 and a piston 21 that is movably inserted into the cylinder 20. A double-rod type damper may be provided, which is movably inserted into the cylinder 20 and has a piston rod 22 extending from both ends of the piston 21 and having both ends protruding from both ends of the cylinder 20.

This damper 19 is different from the damper 8 in that the piston rod 22 extends to both sides of the piston 21 and is also inserted into the extension side chamber R3 and the compression side chamber R4. An accumulator 23 for pressurizing is provided in the piston rod 22.

Both ends of the cylinder 20 are closed by annular rod guides 24 and 25 into which the piston rod 22 is inserted, and the inside of the cylinder 20 is divided into an extension side chamber R3 and a compression side chamber R4 like the damper 8. The piston 21 has a relief valve 21a that communicates the extension side chamber R3 and the compression side chamber R4 and gives resistance to the flow of hydraulic oil moving from the extension side chamber R3 to the compression side chamber R4, and extends from the compression side chamber R4. It is provided with a relief valve 21b that gives resistance to the flow of hydraulic oil moving to the side chamber R3, and an orifice 21c that gives resistance to the flow of hydraulic oil that goes back and forth between the extension side chamber R3 and the compression side chamber R4.

In the damper 19, the cylinder 20 is fixedly connected to the rod 6, and the tip of the piston rod 22 is rotatably connected to the bracket 4a of the cylinder 4 of the right wheel side main damper MDR, and the rod 6 is connected to the right wheel. It is connected to the right wheel WR via the side main damper MDR. The damper 19 may have the cylinder 20 connected to the right wheel WR side and the piston rod 22 connected to the rod 6 side.

Since the pressure receiving area where the piston 21 receives the pressure of the extension side chamber R3 and the pressure receiving area where the pressure side chamber R4 receives the pressure of the damper 19 configured in this way are equal, the damper 19 does not expand or contract when no external force acts. In the case of this damper 19, since the volume of the piston rod 22 existing in the cylinder 20 at the time of expansion and contraction is always constant, there is no need for volume compensation, and the accumulator 23 prevents the inside of the cylinder 20 from falling below the atmospheric pressure. , Compensates for volume change of hydraulic oil due to temperature change.

When the damper 19 is a double-rod type damper in this way, the damper 19 does not function as a spring at all, so that the damping force generator F1 completely affects the roll amount of the vehicle body B controlled by the stabilizer (spring member) 1. It disappears, and tuning becomes easier. Further, when the damper 19 is a double-rod type damper, there is an advantage that an unbalanced load is not applied to the left wheel WL and the right wheel WR regardless of the stroke position of the damper 19.

When the damper 19 is extended, the damper 19 exerts a damping force at the orifice 21c and the relief valve 21a, and the damper 19 exerts a damping force at the orifice 21c and the relief valve 21b. As shown in FIG. 4, the damping force characteristic of the damper 19 is such that the damping force reaches a plateau and saturates at the first damper speed V1 as shown in FIG. Therefore, even if the damper 19 is used for the damping force generator F1 instead of the damper 8, the same effect can be obtained, and the damping force is generated when the vehicle body B rolls at a high roll rate. The damping force generated by the device F1 becomes too high, and the roll rigidity of the vehicle body B suddenly increases, so that there is no concern that the passengers of the vehicle will feel uncomfortable or uncomfortable and the riding comfort will be impaired.

Similar to the damper 8, this damper 19 also exhibits a damping force close to the maximum damping force when the damper speed reaches the first damper speed V1 set to 0.02 m / sec or less. When there is a displacement difference between the right wheel and the right wheel WR, it becomes possible to suppress the vibration of the vehicle body B in the very low speed range that cannot be covered by the left wheel side main damper MDL and the right wheel side main damper MDR. You can further improve your comfort. Further, if the damping force characteristic of the damper 19 is the characteristic shown in FIG. 5 described above in relation to the damping force characteristic of the left wheel side main damper MDL and the right wheel side main damper MDR, the left wheel WL and the right wheel WR When there is a displacement difference between the two, it becomes possible to suppress the vibration of the vehicle body B in the very low speed range that cannot be covered by the left wheel side main damper MDL and the right wheel side main damper MDR, and the riding comfort in the vehicle can be further improved. ..

<Second embodiment>
As shown in FIG. 7, the suspension device S2 according to the second embodiment has a left wheel WL and a right wheel when there is a difference in vertical displacement between the left wheel WL and the right wheel WR of the vehicle with respect to the vehicle body B of the vehicle. The difference between the spring member 30 that generates a spring force in the direction of reducing the displacement difference between the left wheel WL and the right wheel WR with respect to the WR, and the vertical displacement between the left wheel WL and the right wheel WR of the vehicle with respect to the vehicle body B. In the case of the left wheel WL and the right wheel WR, a damping force generator F2 that acts in parallel with the spring force in the direction of reducing the displacement difference between the left wheel WL and the right wheel WR is provided.

Further, in the suspension device S2 of the second embodiment, similarly to the suspension device S1, in addition to the above configuration, the left wheel side main damper MDL and the left wheel side suspension spring interposed between the vehicle body B and the left wheel WL The SPL is provided with a right wheel side main damper MDR and a right wheel side suspension spring SPR interposed between the vehicle body B and the right wheel WR.

The damping force generating device F2 in the suspension device S2 of the second embodiment has a U-shaped rod 31 rotatably mounted along the lateral direction with respect to the vehicle body B, and one end of the rod 31 is a left wheel. The spring member 30 has a damper 32L connected to the WL and a damper 32R connecting the other end of the rod 31 to the right wheel WR, and the spring member 30 is a left wheel side spring interposed between one end of the rod 31 and the left wheel WL. It is composed of 30L and a right wheel side spring 30R interposed between the other end of the rod 31 and the right wheel WR.

The rod 31 has a U shape, and the center of the rod 31 is rotatably mounted on the vehicle body B around the axis in the lateral direction of the vehicle body B. For the rod 31, the setting of the moment of inertia of area and the material are selected so that the rod 31 has high rigidity and twisting is extremely small with respect to a torque load.

The dampers 32L and 32R have the same configuration as the damper 8, and as shown in FIG. 7, each cylinder 10 is connected to the corresponding end of the rod 31, and the piston rod 12 corresponds to the left wheel side, respectively. The main damper MDL and the right wheel side main damper MDR are rotatably connected to a bracket 4a provided on the cylinder 4. The damper 32L may directly connect the left wheel WL and the rod 31, or the damper 32R may directly connect the right wheel WR and the rod 31. In addition, dampers 32L and 32R
May connect the cylinder 10 to the wheel side and the piston rod 12 to the rod 31 side. The dampers 32L and 32R may be double-rod type dampers for the damper 19.

Further, the dampers 32L and 32R include an annular spring receiver 10a provided on the outer periphery of the cylinder 10 and an annular spring receiver 12a provided on the outer periphery on the tip end side of the piston rod 12. A left wheel side spring 30L made of a coil spring is interposed between the spring receivers 10a and 12a of the damper 32L to urge the damper 32L in the extension direction. A right wheel side spring 30R made of a coil spring is interposed between the spring receivers 10a and 12a of the damper 32R to urge the damper 32R in the extension direction. The left wheel side spring 30L may be directly interposed between the rod 31 and the left wheel WL, but when it is mounted on the outer circumference of the damper 32L and assembled into the damper 32L, the rod 31 and the left wheel WL are assembled together with the damper 32L. It can be installed between and, making it easy to assemble. Similarly, the right wheel side spring 30R may be directly interposed between the rod 31 and the right wheel WR, but when it is mounted on the outer circumference of the damper 32R and assembled into the damper 32R, the rod 31 is assembled together with the damper 32R. It can be installed between the right wheel WR and the right wheel WR, facilitating assembly.

In the suspension device S2 configured in this way, when the left wheel WL and the right wheel WR approach or separate from the vehicle body B, the dampers 32L and 32R expand and contract because there is no displacement difference between the left wheel WL and the right wheel WR. However, the left wheel side spring 30L and the right wheel side spring 30R do not expand or contract either. When the left wheel WL and the right wheel WR are displaced in the vertical direction in the same phase with respect to the vehicle body B in this way, the spring member 30 does not act on the left wheel WL and the right wheel WR, and the damping force is not applied. The generator F2 also does not act on the damping force.

On the other hand, when the vehicle body B tilts to the left and the left wheel WL approaches the vehicle body B and the right wheel WR separates, the damper 32L and the left wheel side spring 30L extend, and the damper 32R and the right wheel side spring 30R contract. .. In such a situation, the damper 32L on the left wheel WL side exerts a damping force that suppresses the approach of the left wheel WL to the vehicle body B according to the roll rate of the vehicle body B, and the damper 32R of the right wheel WR is the right wheel WR. It exerts a damping force that suppresses the separation from the vehicle body B. Further, since the left wheel side spring 30L expands, the spring force exerted according to the roll amount of the vehicle body B is reduced, and the right wheel side spring 30R contracts, so that the vehicle body of the right wheel WR responds to the roll amount of the vehicle body B. It exerts a spring force that suppresses separation from B.

On the contrary, when the vehicle body B tilts to the right and the left wheel WL separates from the vehicle body B and the right wheel WR approaches, the damper 32L and the left wheel side spring 30L contract, and the damper 32R and the right wheel side spring 30R extend. do. In such a situation, the damper 32L on the left wheel WL side exerts a damping force that suppresses the separation of the left wheel WL from the vehicle body B according to the roll rate of the vehicle body B, and the damper 32R of the right wheel WR is the right wheel WR. It exerts a damping force that suppresses the approach to the vehicle body B. Further, since the left wheel side spring 30L contracts, it exerts a spring force that suppresses the separation of the right wheel WR from the vehicle body B according to the roll amount of the vehicle body B, and the right wheel side spring 30R extends, so that the vehicle body B rolls. The spring force exerted is reduced according to the amount.

In this way, in the suspension device S2, the damping force generator F2 exerts the spring force for suppressing the relative displacement of the left wheel WL and the right wheel WR as the roll suppressing force according to the roll amount of the vehicle body B, while the damping force generating device F2 is the vehicle body. It exerts a damping force that suppresses the relative displacement of the left wheel WL and the right wheel WR according to the roll rate of B.

As described above, in the suspension device S2 of the second embodiment, as shown in FIG. 7, the suspension device S2 of the second embodiment has the left wheel WL and the right wheel WR of the vehicle with respect to the vehicle body B of the vehicle. A spring member 30 that generates a spring force in a direction that reduces the displacement difference between the left wheel WL and the right wheel WR with respect to the left wheel WL and the right wheel WR when there is a difference in displacement in the vertical direction, and a spring member 30 with respect to the vehicle body B. When there is a difference in vertical displacement between the left wheel WL and the right wheel WR of the vehicle, the damping force in the direction of reducing the displacement difference between the left wheel WL and the right wheel WR is parallel to the spring force with respect to the left wheel WL and the right wheel WR. The damping force generator F2 is provided with a damping force generator F2 that is rotatably mounted along the lateral direction with respect to the vehicle body B, and one end of the rod 31 is a left wheel WL. The spring member 30 has a damper 32L connected to the rod 31 and a damper 32R connecting the other end of the rod 31 to the right wheel WR, and the spring member 30 is a left wheel side spring 30L interposed between one end of the rod 31 and the left wheel WL. And the right wheel side spring 30R interposed between the other end of the rod 31 and the right wheel WR.

Even in the suspension device S2 configured in this way, similarly to the suspension device S1 of the first embodiment, the roll suppressing force is exerted by the spring force exerted by the spring member 30 with respect to the roll amount of the vehicle body B. Then, the damping force generator F2 exerts a damping force depending on the roll rate of the vehicle body B, and can suppress the roll of the vehicle body B. In the suspension device S2, since the spring member 30 and the damping force generator F2 are interposed between the left wheel WL and the right wheel WR in parallel, the roll suppressing force exerted by the spring member 30 is generated as a damping force. The device F2 is not reduced, there is no concern that the roll suppressing force becomes insufficient, and the riding comfort in the vehicle can be improved.

Further, in the suspension device S2, since the spring member 30 and the damping force generator F2 are interposed between the left wheel WL and the right wheel WR in parallel, the spring member 30 and the damping force generator F2 are opposed to each other. Since the influence on the characteristics of the spring member 30 is small, the tuning of the spring member 30 and the damping force generator F2 becomes very easy. From the above, according to the suspension device S2 of the present invention, it is possible to improve the riding comfort in the vehicle and facilitate the tuning of the roll suppressing force.

Further, in the suspension device S2 of the second embodiment, a U-shaped rod 31 on which the damping force generating device F2 is rotatably mounted along the lateral direction with respect to the vehicle body B, and one end of the rod 31 is a left wheel. A left wheel side spring 30L having a damper 32L connected to the WL and a damper 32R connecting the other end of the rod 31 to the right wheel WR, and a spring member 30 interposed between one end of the rod 31 and the left wheel WL. And a right wheel side spring 30R interposed between the other end of the rod 31 and the right wheel WR. When the suspension device S2 is configured in this way, the stabilizer is not required. Therefore, the spring member 30 and the damping force generator F2 may be incorporated in the existing vehicle instead of the stabilizer, and the mountability on the vehicle is also improved. ..

As with the damper 8, the damping force characteristics of the dampers 32L and 32R are such that the damping force saturates when the damper speed becomes the first damper speed V1 or more, or the first damper speed V1 is 0.02 m / sec or less. When set to, the same action and effect as that of the suspension device S1 of the first embodiment can be obtained, and the relationship between the damping force characteristics of the left wheel side main damper MDL and the right wheel side main damper MDR is shown in FIG. If the characteristics shown in (1) are met, in a situation where a displacement difference occurs between the left wheel WL and the right wheel WR, the vehicle body B in the very low speed range that cannot be covered by the left wheel side main damper MDL and the right wheel side main damper MDR. Vibration can be suppressed, and the riding comfort in the vehicle can be further improved.

Although the preferred embodiments of the present invention have been described in detail above, they can be modified, modified, and modified as long as they do not deviate from the claims.

1 ... Stabilizer (spring member), 6,31 ... Rod, 7 ... Connecting rod, 8,19,32L, 32R ... Damper, 10,20 ... Cylinder, 11,21 ...・ Piston, 12, 22 ・ ・ ・ Piston rod, 13 ・ ・ ・ Balance spring, 30L ・ ・ ・ Left wheel side spring, 30R ・ ・ ・ Right wheel side spring, 30 ・ ・ ・ Spring member, B ・ ・ ・ Body, F1 , F2 ... Damping force generator, MDL ... Left wheel side main damper, MDR ... Right wheel side main damper, S1, S2 ... Suspension device, V1 ... First damper speed, V2 ...・ Second damper speed, WL ・ ・ ・ left wheel, WR ・ ・ ・ right wheel

Claims (7)

When there is a difference in the vertical displacement of the left wheel and the right wheel of the vehicle with respect to the vehicle body, a spring force is applied in the direction of reducing the displacement difference between the left wheel and the right wheel with respect to the left wheel and the right wheel. The generated spring member and
When there is a difference in the vertical displacement of the left wheel and the right wheel of the vehicle with respect to the vehicle body, a damping force is applied in the direction of reducing the displacement difference between the left wheel and the right wheel with respect to the left wheel and the right wheel. A suspension device including a damping force generator that acts in parallel with the spring force. The spring member is a stabilizer having a U-shaped torsion bar whose one end is connected to the left wheel and the other end is connected to the right wheel.
The damping force generator includes a U-shaped rod that is rotatably mounted with respect to the vehicle body in the lateral direction, and a connecting rod that connects one end of the rod to one of the left wheel and the right wheel. The suspension device according to claim 1, further comprising a damper that connects the other end of the rod to the other of the left wheel and the right wheel. The damping force generator includes a U-shaped rod that is rotatably mounted along the lateral direction with respect to the vehicle body, a damper that connects one end of the rod to one of the left wheel and the right wheel, and the rod. Has a damper that connects the other end of the left wheel to the other of the right wheel.
The spring member has a left wheel side spring interposed between one end of the rod and the left wheel, and a right wheel side spring interposed between the other end of the rod and the right wheel. The suspension device according to claim 1. The damper is
Cylinder and
A piston that is movably inserted into the cylinder,
A piston rod that is movably inserted into the cylinder and extends from one end of the piston and projects out of the cylinder.
It has a balance spring that exerts an urging force in a direction that causes the piston rod to enter the cylinder against a rod reaction force that causes the piston rod to move out of the cylinder due to pressure in the cylinder.
The suspension device according to claim 2 or 3, wherein when the piston is located at the center of the stroke with respect to the cylinder, the reaction force of the rod and the urging force of the balance spring are balanced. The damper is
Cylinder and
A piston that is movably inserted into the cylinder,
The suspension device according to claim 2 or 3, further comprising a piston rod that is movably inserted into the cylinder and extends from both ends of the piston and has both ends protruding from both ends of the cylinder. The suspension device according to any one of claims 2 to 5, wherein the damper has a damping force characteristic in which the damping force is saturated when the damper speed becomes equal to or higher than the first damper speed. A left wheel side main damper that is interposed between the vehicle body and the left wheel to suppress vertical vibration of the left wheel with respect to the vehicle body.
A right wheel side main damper, which is interposed between the vehicle body and the right wheel and suppresses vertical vibration of the right wheel with respect to the vehicle body, is provided.
The left wheel side main damper and the right wheel side main damper have a damping force characteristic having a break point in which the damping force changes at a second damper speed in which the damper speed is higher than the first damper speed.
The claim is characterized in that the damping force of the damper when expanding and contracting at the first damper speed is larger than the damping force of the left wheel side main damper and the right wheel side main damper when expanding and contracting at the first damper speed. Item 6. The suspension device according to Item 6.

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