An actuator system for a vehicle suspension system includes: an actuator having a piston and a first fluid chamber separated from a second fluid chamber by the piston; a hydraulic pump having a first port connected by a first hydraulic circuit to the first chamber via a first valve, the first valve being a damper valve operable to variably restrict flow of hydraulic fluid out of the first chamber; a first hydraulic accumulator connected to the first hydraulic circuit between the first port and the first valve; and a second hydraulic accumulator connected to the first port by a second valve, the second valve being a variable pressure relief valve operable to variably restrict flow of hydraulic fluid from the first port to the second hydraulic accumulator.

An actuator system for a vehicle suspension system includes: an actuator having a piston and a first fluid chamber separated from a second fluid chamber by the piston; a hydraulic pump having a first port connected by a first hydraulic circuit to the first chamber via a first valve, the first valve being a damper valve operable to variably restrict flow of hydraulic fluid out of the first chamber; a first hydraulic accumulator connected to the first hydraulic circuit between the first port and the first valve; and a second hydraulic accumulator connected to the first port by a second valve, the second valve being a variable pressure relief valve operable to variably restrict flow of hydraulic fluid from the first port to the second hydraulic accumulator.

A shock absorber including a pressure tube, a piston assembly slidably disposed within the pressure tube, and a fluid transfer tube that extends about the pressure tube is provided. The piston assembly divides an inner volume of the pressure tube into first and second working chambers. An intermediate chamber between the pressure tube and the fluid transfer tube is arranged in fluid communication with the first working chamber. A valve assembly is disposed in fluid communication with the intermediate chamber and the second working chamber. The valve assembly controls fluid flow between the intermediate chamber and the second working chamber. At least part of the intermediate chamber is formed by a fluid transfer channel that extends longitudinally within the fluid transfer tube to provide a fluid flow path extending between the first working chamber and the valve assembly.

A solenoid valve that can be adjusted axially, and hermetically, to a first end of a body of a shock absorber in order to be able to regulate the hydraulic load of the shock absorber as well as guide the movement of the rod in a longitudinal direction. The solenoid valve includes a movable part that can be moved between an open fluid flow position and another closed fluid flow position, a regulating chamber that generates a pressure to move said movable part towards the opening and an elastic element that generates a closing force. Likewise, the solenoid valve also includes electronic means to exert a force on the movable part, to move it in the direction of movement, preferably by means of a magnetic load. The invention also includes a shock absorber with hydraulic load regulation that comprises a solenoid valve, like the one mentioned, adjusted hermetically to a first end of the body of said shock absorber.

A bidirectional vehicle may be capable of traveling in either of two directions and may change its direction of travel at any point for various reasons. In response to a change in the direction of travel, systems of a bidirectional vehicle may adjust one or more suspension components using various techniques to configure the vehicle with a higher ride frequency at the trailing axle than at the leading axle to enhance the ride quality and handling capabilities of the vehicle.

A shock absorber includes: a cylinder; a piston slidably inserted into the cylinder; a piston rod connected to the piston and extending outside the cylinder; a main valve that generates a damping force; a pilot chamber that applies pressure to the main valve; an introduction passage that introduces the fluid into the pilot chamber; a pilot passage that communicates the pilot chamber and a downstream side of the main valve with each other; and a control valve provided in the pilot passage. In an upstream side of the pilot passage from the control valve, the pilot passage is provided with a first orifice, a first passage provided in parallel with the first orifice, a first check valve that is opened at a predetermined differential pressure and allows a flow toward the control valve through the first passage, and a second orifice.

Methods and apparatus for position sensitive dampening. In one aspect a fluid damper is provided comprising a damper chamber divided by a piston into a primary compression and a primary rebound chamber; a secondary compression chamber in fluid communication with the damper chamber; and an adjustable fluid meter controlling fluid flow out of the secondary compression chamber.

A shock absorber for a vehicle is disclosed which has a pressure tube defining a fluid chamber, a piston rod, and a piston disposed within the fluid chamber, and carried on the piston rod, which divides the fluid chamber into upper and lower working chambers, and which has a plurality of passages extending between the upper and lower working chambers. A valve disc assembly controls a flow of fluid, and includes a spring disc. The spring disc has a non-symmetrical circumferential shape which enables a stiffness of the valve disc assembly to be tailored so that it begins to open at a first peripheral point, and continuously gradually opens about a non-symmetrical circumferential path until reaching a second peripheral point adjacent the first peripheral point.

A suspension system of an associated vehicle. The suspension system comprises an outer reservoir tube extending along an axis between a first end and a second end and defining a chamber. A piston assembly is at least partially located in the chamber. The piston assembly includes a piston rod and a piston head. A solenoid assembly is connected to the piston rod. The solenoid assembly comprises a core including a core head and a core body. A spool extends about the core body and defines a space. A coil is wrapped around the spool within the space. An induction plate is at least partially located between the spool and the core head. As the input current is modulated the induction plate promotes the induction of eddy currents opposing the field induction attenuating the force ripples of the magnetic field buildup and decay.

A damper system may include an electrically adjustable hydraulic shock absorber having an electromechanical valve and a damper controller. The damper controller may include a solenoid driver circuit electrically coupled to the electromechanical valve, and disposed at the shock absorber. The solenoid driver circuit may be operable to drive the electromechanical valve in an open state in which hydraulic fluid flows between a pressure tube and a reserve tube. The solenoid driver circuit may include a plurality of transistors that are operable to generate a first current to place the electromechanical valve in the open state and a second current less than the first current to hold the electromechanical valve in the open state.