Abstract: A shock absorber works with a variable element (15) which determines the size of a medium passage between the upper and lower sides of a piston (10) in the absorber. The element is arranged so that, with the help of the inertia of its mass, it can carry out a relative displacement movement in its bearing when an acceleration force acts on the mass as a result of the acceleration of the object. The element (15), responsive to the displacement movement, exerts influence on the size of the medium passage.

Abstract: A shock absorber has an arrangement for bringing about different kinds of damping characteristics, in response to external controls (I) and independently of how the piston speed varies. The shock absorber comprises a piston which works in a cylinder (2) and which has a passage between upper and lower sides (1a, 1b) of the piston. The changes in the damping characteristics are obtained by a restriction in a channel through which a shock absorber medium or fluid flows. A first valve element (7) exerts an influence on the restriction in response to a first pressure which is created by means of a pilot flow running between the upper and lower sides at the piston. The pilot flow is determined by a second valve element (8) which is controllable by electrical control signal.