Variable valve-timing mechanism

Claim 1

IN A CAM-ACTUATED MECHANISM FOR OPENING VALVES OF AN INTERNAL COMBUSTION ENGINE, A CAM HAVING A FIRST AND A SECOND SET OF CAM SURFACES COMPRISING AN OUTER LOBE AND AN INNER LOBE OF SAID CAM, A FIXED BODY, A PAIR OF FLUID-COUPLED LIFTERS DISPOSED TO ABUT RESPECTIVELY SAID OUTER AND INNER LOBES OF SAID CAM AND ARRANGED WITHIN SAID BODY IN COAXIAL SLIDING ENGAGEMENT AND HAVING PORTIONS DISPOSED FOR RELATIVE TELESCOPING MOVEMENT, ONE OF SAID LIFTERS ENGAGING A PUSH ROD FOR OPENING A VALVE OF AN ENGINE, SAID LIFTERS DEFINING THEREBETWEEN AN ANNULAR CHAMBER ADAPTED TO CONTAIN A BODY OF LIQUID COMPRISING FLUID MEANS COUPLING ONE OF SAID LIFTERS TO THE OTHER, THE DEGREE OF COUPLING BETWEEN SAID LIFTERS BEING A FUNCTION OF LINEAR DISPLACMENT VELOCITY OF SAID LIFTERS IN RESPONSE TO CAM ACTION THEREAGAINST, INLET CONDUIT MEANS COMMUNICATING WITH SAID ANNULAR CHAMBER FOR INTRODUCING LIQUID INTO SAID CHAMBER, AND PORTING MEANS FOR CONTROLLING THE RATE OF ESCAPE OF FLUID FROM SAID CHAMBER DURING AXIAL DISPLACEMENT OF SAID LIFTERS RELATIVE TO ONE ANOTHER, AND THEREBY DETERMINING THE DEGREE OF FLUID COUPLING OF SAID LIFTERS TO ONE ANOTHER.