Regenerative valve hydraulic actuator

Regenerative valve hydraulic actuator (1) for a reciprocating piston compressor or engine (100) which comprises at least one piston (101) connected to transmission means (102) to reciprocate in a cylinder (103) closed by a compressor or engine cylinder head (104), said piston (101), said cylinder (103) and said cylinder head (104) forming a compression or combustion chamber (105) into which opens at least one intake line (106) and at least one exhaust or discharge line (107), one or both of said two lines (106, 107) being connected to said chamber (105) by a line orifice (10) that a valve (8) can block when it rests on a valve seat (11) the regenerative valve hydraulic actuator comprising:

• At least one high-pressure hydraulic feed pump (2) that can admit a hydraulic fluid (3) from a low-pressure accumulator (4) or a fluid tank (46) via a low-pressure feed line (47) to discharge said fluid (3) to a high-pressure accumulator (5) via a high-pressure feed line (48);
• At least one actuator (6) which comprises an actuator cylinder (25) capped by an actuator cylinder head (49), said cylinder (25) being attached directly or indirectly to the compressor or engine cylinder head (104) whereas said cylinder (25) and the actuator cylinder head (49) form with an actuator piston (26) an actuator hydraulic chamber (7), said piston (26) being mechanically connected by transmission means (9) to the valve (8), said means (9) being such that if the actuator hydraulic chamber (7) is subjected to a pressure exerted by the hydraulic fluid (3), the actuator piston (26) tends to move said valve (8) away from the valve seat (11) with which it cooperates;
• At least one valve return device (12) which exerts on the valve (8) a force opposite that which the actuator (6) is able to produce, said device (12) therefore tending to return the valve (8) into contact with the valve seat (11) with which it cooperates;
• At least one valve lifter hydraulic valve (13) that can open or close a high-pressure lifter line (14) which connects the high-pressure accumulator (5) to the actuator hydraulic chamber (7);
• At least one lifter check valve (15) placed in an inertial lifter line (16) that connects the low-pressure accumulator (4) or the fluid tank (46) to the actuator hydraulic chamber (7), said check valve (15) allowing the hydraulic fluid (3)—via said line (16)—to flow from the low-pressure accumulator (4) or the fluid tank (46) to the actuator hydraulic chamber (7), but not in the opposite direction;
• At least one valve closure hydraulic valve (17) that can open or close a closure and regeneration line (18) which connects the actuator hydraulic chamber (7) with a fluid intake (19) which a closure and regeneration hydraulic motor (20) includes, a fluid outlet (21) which said motor (20) also includes being connected with the low-pressure accumulator (4) or with the fluid tank (46) by a hydraulic motor low-pressure return line (22);
• At least one progressive lever arm ratio lever (27) constituting all or part of the transmission means (9), said lever (27) exposing at least one point of application of the force of the actuator (28) to which the actuator piston (26) can apply directly or indirectly a driving or resisting force, at least one point of application (29) of the force of the valve (8) to which the valve can apply directly or indirectly a driving or resisting force, and at least one point of application of the reaction force on the cylinder head (30) at which a force is applied directly or indirectly to the compressor or engine cylinder head (104).