SUSPENSION SYSTEM FOR VEHICLE

• US 20090273147A1
• Filed: 10/25/2006
• Published: 11/05/2009
• Est. Priority Date: 10/26/2005
• Status: Active Grant

• Current Assignee: KYB Corp., Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation), University of Tokyo
• Original Assignee: Kayaba Industry Company Limited, Toyota Jidosha Kabushiki Kaisha (Toyota Motor Corporation), University of Tokyo
• Inventors: Inoue, Hirofumi, Kondo, Takuhiro, Suda, Yoshihiro
• Granted Patent: US 8,103,408 B2
• Time in Patent Office: Days
• US Class Current: 280/5.510
• CPC Class Codes: B60G 17/06 Characteristics of dampers , e.g. mechanical dampersB60G17/015 takes precedence
• CPC Class Codes: B60G 2202/42 Electric actuator
• CPC Class Codes: B60G 2400/102 vertical
• CPC Class Codes: B60G 2400/104 lateral or transversal with regard to vehicle
• CPC Class Codes: B60G 2400/106 longitudinal with regard to vehicle, e.g. braking
• CPC Class Codes: B60G 2400/204 Vehicle speed
• CPC Class Codes: B60G 2400/252 vertical
• CPC Class Codes: B60G 2400/41 Steering angle
• CPC Class Codes: B60G 2500/10 Damping action or damper
• CPC Class Codes: B60G 2800/012 Rolling condition
• CPC Class Codes: B60G 2800/014 Pitch; Nose dive
• CPC Class Codes: F16F 15/03 using magnetic or electromagnetic means F16F9/53, F16F15/005 take precedence

Abstract

In a system including four electromagnetic absorbers for respective four vehicle wheels, motor coils of two respective electromagnetic absorbers disposed corresponding to two diagonally located wheels are connected forming a closed loop including the coils. A generated damping force magnitude can be made different between an instance directions of respective movements of the diagonally located two wheels with respect to the vehicle body are the same, and an instance the directions are opposite each other. Each electromagnetic absorber includes a resistor cooperating with the corresponding coil forming a closed loop, and selectively establishes: a connected state in which one of the four coils and any of the other three coils are connected to form a closed loop; and a non-connected state in which the one of the four coils is not connected to any other coil. An appropriate vibration suppressing action is exhibited with respect to a coupled motion.

Claims

1. A suspension system for a vehicle comprising:

four electromagnetic absorbers which respectively correspond to four wheels of the vehicle and each of which includes;

(A) a sprung-side member coupled to a sprung portion;

(B) an unsprung-side member coupled to an unsprung portion and operable to move relative to the sprung-side member in association with a relative movement of the sprung portion and the unsprung portion; and

(C) a damping-force generating device including a coil and a magnet that move relative to each other in association with a relative movement of the sprung-side member and the unsprung-side member and operable to generate a damping force with respect to the relative movement of the sprung-side member and the unsprung-side member depending on an electromotive force generated by a relative movement of the coil and magnet; and

a coil connecting device configured to electrically connect the coils of the damping-force generating devices of the respective four electromagnetic absorbers so as to form two closed loops which respectively correspond to two wheel pairs each consisting of diagonally located two of the four wheels and each of which includes two coils, of the respective damping-force generating devices of two of the four electromagnetic absorbers, which two electromagnetic absorbers are provided for a corresponding one of the two wheel pairs,

wherein the coil connecting device includes;

two first connection paths which connect first ends of the respective two coils in each of the respective two closed loops and which are joined to each other; and

two second connection paths which connect second ends of the respective two coils in each of the respective two closed loops and which are joined to each other, each of the second ends being opposite to a corresponding one of the first ends.

2. The suspension system according to claim 1, wherein the coil connecting device is configured to connect the two coils constituting one of the two closed loops so as to cause current flows in mutually different directions in the one of the two closed loops, depending on the electromotive forces generated in the respective damping-force generating devices of corresponding two of the four electromagnetic absorbers, when a direction of the relative movement of the sprung portion and the unsprung portion on which is disposed one of the two electromagnetic absorbers that respectively correspond to the two coils constituting the one of the two closed loops is the same as a direction of the relative movement of the sprung portion and the unsprung portion on which is disposed the other of the two electromagnetic absorbers.

3. The suspension system according to claim 1, wherein the connecting device further includes a resistor disposed to join at least one of the two first connection paths and at least one of the two second connection paths to each other.

4. A suspension system for a vehicle comprising four electromagnetic absorbers which respectively correspond to four wheels of the vehicle and each of which includes:

(A) a sprung-side member coupled to a sprung portion;

(B) an unsprung-side member coupled to an unsprung portion and operable to move relative to the sprung-side member in association with a relative movement of the sprung portion and the unsprung portion; and

(C) a damping-force generating device including a coil and a magnet that move relative to each other in association with a relative movement of the sprung-side member and the unsprung-side member and operable to generate a damping force with respect to the relative movement of the sprung-side member and the unsprung-side member depending on an electromotive force generated by a relative movement of the coil and magnet,

wherein the four electromagnetic absorbers include respective four damping-force generating devices each as the damping-force generating device, each of the four damping-force generating device including a resistor that cooperates with the coil of said each of the four damping-force generating devices to form a closed loop, and

the suspension system further comprises a coil connecting device which selectively establishes owing to an operation thereof, for each of the four damping-force generating devices, one of (a) a connected state in which two coils consisting of the coil of one of the four damping-force generating devices and the coil of any one of the other three damping-force generating devices except the one of the four damping-force generating devices are electrically connected to each other so as to form a closed loop including the two coils and (b) a non-connected state in which the coil of the one of the four damping-force generating devices is not connected to any of the coils of the other three damping-force generating devices.

5. The suspension system according to claim 4, wherein the coil connecting device is configured to connect the two coils constituting the closed loop so as to cause current flows in mutually different directions in the closed loop, depending on the electromotive forces generated in the respective damping-force generating devices of corresponding two of the four electromagnetic absorbers, when a direction of the relative movement of the sprung portion and the unsprung portion on which is disposed one of the two electromagnetic absorbers that respectively correspond to the two coils is the same as a direction of the relative movement of the sprung portion and the unsprung portion on which is disposed the other of the two electromagnetic absorbers.

6. The suspension system according to claim 4, further comprising a control device which controls the suspension system,

wherein the control device includes a coil-connecting-device control portion which controls the operation of the coil connecting device such that the coil of at least one of the four damping-force generating devices and the coil of any one of the other damping-force generating devices are connected to each other, when a vibration that should be suppressed is being generated in the vehicle.

7. The suspension system according to claim 6,

wherein the control device further includes a vibration-mode judging portion which judges a mode of the vibration that is being generated in the vehicle, and

wherein the coil-connecting-device control portion is configured to change the coil of one of the other three damping-force generating devices that is to be connected to the coil of one of the four damping-force generating devices, based on a judgment made by the vibration-mode judging portion.

8. The suspension system according to claim 7, wherein the vibration-mode judging portion is configured to judge, as the mode of the vibration, at least one of a roll-vibration mode in which is being generated a roll vibration that should be suppressed and a pitch-vibration mode in which is being generated a pitch vibration that should be suppressed.

9. The suspension system according to claim 8,

wherein the vibration-mode judging portion is configured to judge, as the mode of the vibration, at least the roll-vibration mode in which is being generated the roll vibration that should be suppressed, and

wherein the coil-connecting-device control portion is configured, when the mode of the vibration is the roll-vibration mode, to establish a connected state in which are connected two coils of the damping-force generating devices of two of the four electromagnetic absorbers respectively provided for left and right wheels, so as to form the closed loop including the two coils, on at least one of a front-wheel side and a rear-wheel side.

10. The suspension system according to claim 8,

wherein the vibration-mode judging portion is configured to judge, as the mode of the vibration, at least the pitch-vibration mode in which is being generated the pitch vibration that should be suppressed, and

wherein the coil-connecting-device control portion is configured, when the mode of the vibration is the pitch-vibration mode, to establish a connected state in which are connected two coils of the damping-force generating devices of two of the four electromagnetic absorbers respectively provided for front and rear wheels, so as to form the closed loop including the two coils, on at least one of a left-wheel side and a right-wheel side.

11. The suspension system according to claim 7, further comprising a motion-state-index-amount detecting device which detects a motion-state index amount indicative of a state of a motion of the vehicle or a part of the vehicle,

wherein the vibration-mode judging portion is configured to judge the mode of the vibration based on the motion-state index amount detected by the motion-state-index-amount detecting device.

12. The suspension system according to claim 11,

wherein the motion-state-index-amount detecting device includes stroke-amount detectors provided for the respective four wheels to detect, as the motion-state index amount, a stroke amount of the sprung portion and the unsprung portion for each of the four wheels, and

wherein the vibration-mode judging portion is configured to judge the mode of the vibration based on the stroke amount detected for said each of the four wheels by the corresponding stroke-amount detector.

13. The suspension system according to claim 11,

wherein the motion-state-index-amount detecting device includes acceleration detectors provided for the respective four wheels to detect, as the motion-state index amount, at least one of vertical acceleration of the sprung portion and vertical acceleration of the unsprung portion for each of the four wheels, and

wherein the vibration-mode judging portion is configured to judge the mode of the vibration based on the at least one of the vertical acceleration of the sprung portion and the vertical acceleration of the unsprung portion detected for said each of the four wheels by the corresponding acceleration detector.