US 12,263,709 B2
Vehicle suspension control device including a damping force adjustable shock absorber
Ryusuke Hirao, Kamagaya (JP)
Assigned to HITACHI ASTEMO, LTD., Ibaraki (JP)
Appl. No. 17/277,440
Filed by Hitachi Astemo, Ltd., Ibaraki (JP)
PCT Filed Sep. 18, 2019, PCT No. PCT/JP2019/036498
§ 371(c)(1), (2) Date Mar. 18, 2021,
PCT Pub. No. WO2020/075455, PCT Pub. Date Apr. 16, 2020.
Claims priority of application No. 2018-193609 (JP), filed on Oct. 12, 2018.
Prior Publication US 2021/0354523 A1, Nov. 18, 2021
Int. Cl. B60G 17/0165 (2006.01); B60G 17/015 (2006.01)
CPC B60G 17/0165 (2013.01) [B60G 17/0152 (2013.01); B60G 2202/24 (2013.01); B60G 2400/202 (2013.01); B60G 2400/252 (2013.01); B60G 2400/821 (2013.01); B60G 2500/10 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A suspension control device, comprising:
a damping force adjustable shock absorber provided between two members of the vehicle, the two members being movable relative to each other;
a non-linear spring disposed in parallel with the damping force adjustable shock absorber and provided between two members of the vehicle, the two members being movable relative to each other; and
a controller configured to adjust a damping force of the damping force adjustable shock absorber,
wherein the damping force adjustable shock absorber includes:
a cylinder which encloses working fluid;
a piston which is provided in the cylinder so as to be slidable;
a piston rod, which is fixed to the piston so as to extend to the outside of the cylinder; and
a damping force adjustment mechanism configured to adjust a damping force generated when the piston relatively slides in the cylinder; and
wherein the controller controls the damping force adjustment mechanism, the controller being configured to:
obtain a relative speed between the two members and a vehicle height using a vehicle height sensor and a vehicle speed sensor;
execute a full extension suppression control of adjusting the damping force to be larger than when the piston is in a neutral position, when a relative position between the cylinder and the piston approaches a full extension position in an extension stroke in which a distal end of the piston rod spaces apart from the cylinder, the relative position being input from the outside;
execute a full compression suppression control of adjusting the damping force to be larger than when the piston is in a neutral position, when the relative position between the cylinder and the piston approaches a full compression position in a compression stroke in which the distal end of the piston rod approaches the cylinder, the relative position being input from the outside;
set a stroke from a neutral position of the piston in the cylinder to a full compression control start position so as to be longer than a stroke from the neutral position to a full extension control start position; and
correct a control command in accordance with a product of the vehicle height and the relative speed between the two members.