Abstract: In a vehicle suspension system including a hydraulic actuator between a sprung mass consisting substantially of a vehicle body and an unsprung mass consisting substantially of a wheel, a force proportional to but opposite in phase to an inertia force acting on the unsprung mass is applied by the actuator to the unsprung mass so that the ability of the tire to maintain contact with the road surface may be improved. This produces very little effect on the behavior of the sprung mass, but the vehicle handling is significantly improved. Better contact with the road surface not only improves the vehicle handling but also reduces the consumption of energy by the hydraulic actuator. A particularly favorable result can be obtained when the hydraulic actuator further applies a damping force proportional to the absolute velocity of the sprung mass to the sprung mass.

Abstract: In an active vehicle suspension system employing a spring and a hydraulic actuator for supporting a wheel relative to a vehicle body, a control unit actuates the actuator so as to cancel the force applied by the spring force of the spring and a damping force applied by the hydraulic actuator. This damping force is typically produced by the flow resistance which the hydraulic oil encounters in the hydraulic circuit. This control action is carried out according to a signal obtained by processing an output of a displacement sensor between the wheel and the vehicle body with a first-order lead filter circuit. Thus, the control action is based on a readily available and highly responsive detection signal, an accurate and stable vibration control of the sprung mass of the vehicle or the vehicle body is made possible.

Abstract: An elongate handwriting implement with a rotatable decoration on the rear end is disclosed. The rear end of an elongate handwriting casing has the decoration. The decoration includes a tubular fixed element fitting around the rear end of the handwriting casing and a hollow rotatable decoration body. The cylindrical surface of the rear end of the fixed element has a plurality of outwardly radially extending camming pins. The front end of the decoration body is open. The interior surface of the decoration body has an annular cam follower defining a plurality of follower grooves engaging the camming pins. The front ends of the follower grooves are open. The decoration body is rotatably and axially movably mounted to the fixed element in such a manner that the camming pins can be in and out of engagement with the follower grooves. The decoration body is rotatably connected to a handle assembly for a writing core through a decoration core extending in the axis of and within the fixed element.