Marelli Suspension Systems Italy S.p.a.

Way Assauto Srl

Sistemi Sospensioni S.p.a.

Instituto Tecnologico Y De Estudios Superiores De Monterrey

Fabio Cotto

Giordano Greco

Piero Antonio Conti

Marco Di Vittorio

Walter Bruno

Simone Marchetti

Benjamin Talon

Nicola Amati

Renato Galluzzi

Manfredi Tornabene

A method for controlling a suspension system for a vehicle to obtain optimal parameters for the damping coefficients of the vehicle suspension that minimize acceleration along a heave axis, angular acceleration around a roll axis and angular acceleration around a pitch axis is provided. These parameters may be recorded during the tuning phase or may also be continuously obtained during use of the vehicle by an end user. Also disclosed is a suspension system for a vehicle configured to advantageously operate according to the method.

Method for controlling variable damping suspensions

The suspension includes a hydraulic actuator and a supply hydraulic circuit connected to the hydraulic actuator to supply a compression chamber and an extension chamber of the hydraulic actuator with a working fluid. The supply hydraulic circuit includes a hydraulic pump, a high-pressure line connected to a delivery port of the hydraulic pump, a low-pressure line connected to a suction port of the hydraulic pump, and a flow control valve connected on one side to the compression chamber and extension chamber of the hydraulic actuator and on the other side to the high-pressure line and low-pressure line. The flow control valve is a rotary spool valve having a spool which is rotatable continuously between a plurality of operating positions.

Active suspension for a vehicle

A method for controlling the damping characteristic of a shock absorber of a vehicle, particularly for compensating the variation of the operating temperature of the shock absorber, in an active or semi-active suspension system. The compensation of the variation of the operating temperature of the shock absorber takes place by: estimating a mechanical power dissipated in heat by the shock absorber; estimating a thermal power exchanged by the shock absorber with the environment; evaluating the current operating temperature of the shock absorber as a function of the dissipated mechanical power and of the thermal power exchanged with the environment; and controlling the driving current of the control valve of the shock absorber according to a shock absorber reference model indicating a relationship between the damping force of the shock absorber, the operating temperature of the shock absorber and the driving current of the control valve.

Compensation of the thermal effect in a vehicle suspension system

A vehicle suspension is disclosed having a hydraulic actuator, a cylinder, a piston mounted inside the cylinder dividing the cylinder into a compression chamber and an extension chamber, and a supply hydraulic circuit connected to the actuator to supply the compression chamber and the extension chamber with working fluid. The supply hydraulic circuit includes a high-pressure line connected to a delivery port of a hydraulic pump, a low-pressure line connected to a suction port of the pump, a spool valve connected to the compression and extension chambers of the actuator and to the high-pressure line and to the low-pressure line to put the chambers of the actuator in communication with the lines of the supply hydraulic circuit, and a first pressure accumulator connected to the high-pressure line. The spool valve connects the compression chamber and/or the extension chamber of the actuator with the high-pressure line.

A method for estimating damping characteristics of shock absorbers in an active or semi-active suspension involves providing a reference model of a nominal relation between a road severity index related to vertical acceleration values, and the mean driving current of the control valves of the shock absorbers, acquiring respective relative acceleration or speed data of at least the front wheels of the vehicle with respect to the vehicle body, determining a value of the road severity index starting from relative acceleration or speed data of the front wheels of the vehicle with respect to the vehicle body, acquiring values representative of the mean driving current of the control valve of each shock absorber, comparing acquired value of the mean driving current with an expected value of the nominal mean driving current determined as a function of the road severity index according to the reference model, and determining a degradation condition if the acquired value does not correspond to the expected value.

Recognition of degraded performance in a vehicle suspension system

A shock-absorber has a cylindrical body having an inner and an outer cylindrical tubes enclosing a reservoir chamber containing oil, and a rod. A piston divides the internal volume of the inner cylindrical tube into a rebound chamber and a compression chamber. The cylindrical body has an intermediate cylindrical tube enclosing with the inner cylindrical tube an intermediate chamber. A first electronically-controlled valve is arranged inside the inner cylindrical tube, so as to be drivingly connected to the rod, and hydraulically connected to the rebound chamber and to the compression chamber to adjust, during rebound phase, flow of the damping fluid from the rebound chamber to the compression chamber. A second electronically-controlled valve is arranged outside the cylindrical body and is hydraulically connected to the reservoir chamber and to the intermediate chamber to adjust, during compression phase, flow of the damping fluid from the compression chamber to the reservoir chamber via the intermediate chamber.

Variable-damping hydraulic shock-absorber for a vehicle suspension

A shock-absorber has an outer cylindrical tube, an inner cylindrical tube, a rod, a main piston and a hydraulic stop member received in a compression chamber and operating during an end section of the compression stroke of the shock-absorber to cause an increase in the hydraulic damping force. The hydraulic stop member has a cup-shaped body mounted in the compression chamber and a first auxiliary piston which is mounted on a cylindrical body rigidly connected to the main piston and is configured to sealingly slide in the cup-shaped body during an end section of the compression stroke, encompassing a working chamber with the cup-shaped body. A sliding member is slidably received inside the cylindrical body for opening or closing at least one first passage of the cylindrical body through which oil flows from the working chamber of the cup-shaped body to the compression chamber of the shock-absorber.

Hydraulic shock-absorber with hydraulic stop member and adjustment device

A rotary damper includes a rotating input member rotating about a rotation axis; a first cylinder and a second cylinder coaxially arranged on opposite sides of the rotation axis; a first and a second pistons slidable inside the first and second cylinders and defining a first and a second working chambers containing incompressible working fluids, respectively; motion conversion mechanisms converting the rotary motion of the rotating input member about the rotation axis into reciprocating motion of the first and second pistons; a third cylinder; a fourth cylinder; and a third and fourth pistons, slidable inside the third and fourth cylinders, respectively and separating the inner volume of the respective cylinder into a respective main chamber in fluid communication with the first working chamber and auxiliary chambers; and the second working chamber and auxiliary chambers respectively.

Rotary damper, particularly for vehicle suspension

A hydraulic shock-absorber comprises an outer cylindrical tube, an inner cylindrical tube defining with the outer cylindrical tube an annular chamber, a main piston slidably mounted in the inner cylindrical tube and dividing the inner volume of the inner cylindrical tube into an extension chamber and a compression chamber, both containing an incompressible damping fluid, a valve assembly mounted on a bottom wall of the inner cylindrical tube and comprising a first compression valve and a first intake valve, a cup-shaped body mounted in the inner cylindrical tube, inside the compression chamber, and an auxiliary piston rigidly connected to the main piston and configured to slide in the cup-shaped body at least during a final section of the compression phase of the shock-absorber. The shock-absorber further comprises a second compression valve configured as a non-return valve allowing the flow of the damping fluid only in the direction from a working chamber of the cup-shaped body towards a lower portion of the compression chamber.

Growing community of inventors

Turin, Italy

Fabio Cotto