Regenerative hydraulic shock-absorber for vehicle suspension

A regenerative hydraulic shock-absorber for vehicle suspension, comprising:

• a cylinder containing a hydraulic working fluid;
• a piston slidably arranged in the cylinder so as to split the cylinder into two variable-volume working chambers, namely a first working chamber, or extension chamber, and a second working chamber, or compression chamber;
• an auxiliary conduit in fluid communication on the one hand with the first working chamber and on the other with the second working chamber;
• a plurality of permanent magnets slidably arranged in the auxiliary conduit to reciprocate along the auxiliary conduit, dragged by the working fluid that flows between the first and second working chambers through the auxiliary conduit as a result of the reciprocating motion of the piston in the cylinder;
• and
• an electric energy generating device for generating electric energy from the movement of the permanent magnets along the auxiliary conduit, said electric energy generating device comprising at least one electric winding wound around a portion of the auxiliary conduit, in such a way that the movement of the permanent magnets along the auxiliary conduit causes the magnetic flux concatenated with said at least one winding to change, thus generating an induced electromotive force in said at least one winding;
• wherein the ratio of the flow cross-section of the auxiliary conduit to the internal working cross-section area of the cylinder is equal to a given value less than 1;
• wherein the ratio of the length of the auxiliary conduit to the length of the stroke of the piston is greater than the reciprocal of said value, the permanent magnets are connected to each other so as to form a train of permanent magnets, and
• the length of the train of permanent magnets is greater than the length of the portion of auxiliary conduit around which said at least one electric winding is wound.