Abstract: A hydraulic actuator circuit is disclosed for use with first and second shock absorbers, which each may include a piston disposed within a housing. The piston helps define upper and lower working chambers. The circuit may have a motor, a first pump, driven by the motor, and is associated with the first shock absorber and the motor. A second pump, driven by the motor, may be associated with the second shock absorber. A first accumulator communicates with both of the first and second pumps. A first switch valve may assist in controlling fluid flow into the chambers of the first shock absorber. A second switch valve may assist in controlling fluid flow into the chambers of the second shock absorber.

Abstract: A hydraulic actuator includes an energy recuperation device which harvests the energy generated from the stroking of a shock absorber. The energy recuperation device can function in a passive energy recovery mode for the shock absorber to store recovered energy as fluid pressure or it can be converted to another form of energy such as electrical energy.

Abstract: A hydraulic actuator circuit is disclosed for use with first and second shock absorbers, which each may include a piston disposed within a housing. The piston helps define upper and lower working chambers. The circuit may have a motor, a first pump, driven by the motor, and is associated with the first shock absorber and the motor. A second pump, driven by the motor, may be associated with the second shock absorber. A first accumulator communicates with both of the first and second pumps. A first switch valve may assist in controlling fluid flow into the chambers of the first shock absorber. A second switch valve may assist in controlling fluid flow into the chambers of the second shock absorber.

Abstract: A control system and method is disclosed for controlling an active suspension and a leveling system for a motor vehicle. The control system may use estimator, controller and management modules. The estimator module processes measured signals obtained from various components and sensors of the vehicle relating to modal displacements, velocities and accelerations, and calculates derived signals which are used as inputs to the controller module. The controller module calculates the desired damper force for each active damper based on motions of the vehicle body and wheels. The management module translates the desired active damper force into an appropriate set of control signals to control each active damper. These operations are performed for each active damper of the vehicle to control each damper in real time.

Abstract: A shock absorber includes a piston which has at least one compression fluid passage, at least one rebound fluid passage and at least one bleed fluid passage. A compression valve assembly closes the at least one compression passage and a rebound valve assembly closes the at least one rebound passage. A bleed valve assembly with the bleed fluid passage defines a first, always open flow path through the piston and a second flow path, separate from the first flow path, through the piston. A bleed disc is movable between a first position where the second flow path is open and a second position where the second flow path is closed.

Abstract: A hydraulic actuator includes an energy recuperation device which harvests the energy generated from the stroking of a shock absorber. The energy recuperation device can function in a passive energy recovery mode for the shock absorber to store recovered energy as fluid pressure or it can be converted to another form of energy such as electrical energy.

Abstract: A hydraulic actuator includes an energy recuperation device which harvests the energy generated from the stroking of a shock absorber. The energy recuperation device can function in a passive energy recovery mode for the shock absorber or an active mode for the shock absorber. The energy that is generated by the energy recuperation device can be stored as fluid pressure or it can be converted to another form of energy such as electrical energy.

Abstract: A shock absorber has a valve assembly having a valve that is biased away from a valve body. A controlled restriction is defined between the valve and the valve body. During stroking of the piston of the shock absorber, the valve moves toward the valve body to close the restriction. The valve assembly can be used in the piston assembly, the base valve assembly or both.

Abstract: A shock absorber includes a piston which has at least one compression fluid passage, at least one rebound fluid passage and at least one bleed fluid passage. A compression valve assembly closes the at least one compression passage and a rebound valve assembly closes the at least one rebound passage. A bleed valve assembly with the bleed fluid passage defines a first, always open flow path through the piston and a second flow path, separate from the first flow path, through the piston. A bleed disc is movable between a first position where the second flow path is open and a second position where the second flow path is closed.

Abstract: A hydraulic actuator assembly includes an actuator, a first sink subsystem in fluid communication with an upper working chamber of the actuator, a second sink subsystem in fluid communication with a lower working chamber of the actuator and a source subsystem in fluid communication with both the upper and lower working chambers of the actuator. A low pressure accumulator is in fluid communication with the upper and lower working chambers, the first and second sink subsystems and source subsystem. A high pressure accumulator is in fluid communication with the first and second sink subsystems and the source subsystem. The hydraulic actuator assembly can generate passive or active forces with or without energy recuperation.

Abstract: A shock absorber has a valve assembly having a valve that is biased away from a valve body. A controlled restriction is defined between the valve and the valve body. During stroking of the piston of the shock absorber, the valve moves toward the valve body to close the restriction. The valve assembly can be used in the piston assembly, the base valve assembly or both.

Abstract: A hydraulic actuator assembly includes an actuator, a first sink subsystem in fluid communication with an upper working chamber of the actuator, a second sink subsystem in fluid communication with a lower working chamber of the actuator and a source subsystem in fluid communication with both the upper and lower working chambers of the actuator. A low pressure accumulator is in fluid communication with the upper and lower working chambers, the first and second sink subsystems and source subsystem. A high pressure accumulator is in fluid communication with the first and second sink subsystems and the source subsystem. The hydraulic actuator assembly can generate passive or active forces with or without energy recuperation.

Abstract: A shock absorber includes a two stage valve assembly that has two valve discs. The second valve disc defines the first stage at lower valve pressures and the first valve disc defines the second stage at higher valve pressures. The two valve discs can be defined by a single piece component or they can be separate components. The second valve disc can permit fluid flow by deflection of the second valve disc or by movement of the entire second valve disc. The two stage valve assembly can be incorporated into the piston assembly of the shock absorber and/or the two stage valve assembly can be incorporated into a base valve assembly.

Abstract: A shock absorber has a first pressure tube and a second pressure tube. A first piston is disposed within the first pressure tube and a second piston is disposed within the second pressure tube. Movement of the first and second pistons within their respective pressure tubes control both damping characteristics for the shock absorber and stiffness for the shock absorber. Valving in the pistons and/or external valving associated with each pressure tube generates both the damping characteristics and the stiffness.

Abstract: A hydraulic actuator includes an energy recuperation device which harvests the energy generated from the stroking of a shock absorber. The energy recuperation device can function in a passive energy recovery mode for the shock absorber or an active mode for the shock absorber. The energy that is generated by the energy recuperation device can be stored as fluid pressure or it can be converted to another form of energy such as electrical energy.

Abstract: A shock absorber includes a two stage valve assembly that has two valve discs. The second valve disc defines the first stage at lower valve pressures and the first valve disc defines the second stage at higher valve pressures. The two valve discs can be defined by a single piece component or they can be separate components. The second valve disc can permit fluid flow by deflection of the second valve disc or by movement of the entire second valve disc. The two stage valve assembly can be incorporated into the piston assembly of the shock absorber and/or the two stage valve assembly can be incorporated into a base valve assembly.

Abstract: A shock absorber has a valve assembly having a valve that is biased away from a valve body. A controlled restriction is defined between the valve and the valve body. During stroking of the piston of the shock absorber, the valve moves toward the valve body to close the restriction. The valve assembly can be used in the piston assembly, the base valve assembly or both.