Energy-recycling hydraulic control main valve

1. An energy-recycling hydraulic control main valve, comprising end covers ( 1 ), a valve core ( 2 ), a left one-way valve ( 3 ) and a right one-way valve ( 4 ); wherein each of two ends of the valve core ( 2 ) is provided with one end cover ( 1 ), the valve core ( 2 ) is provided with a left oil port, a first oil port (A), a second oil port (I/L), a third oil port (I/M), a fourth oil port (I/R), a fifth oil port (B), a right oil port and a sixth oil port (P) thereon; a spring ( 5 ) and a spring seat ( 6 ) are arranged between each of the end covers ( 1 ) and the valve core ( 2 ); the left one-way valve ( 3 ) and the right one-way valve ( 4 ) are respectively embedded in the left end and the right end of the valve core ( 2 ); the left one-way valve ( 3 ) is composed of a left valve seat ( 3 - 1 ), a left cone valve core ( 3 - 2 ) and a left spring ( 3 - 3 ); a conical surface of the left cone valve core ( 3 - 2 ) is closely attached to a left conical surface of the valve core ( 2 ) by the action of the left spring ( 3 - 3 ); the right one-way valve ( 4 ) is composed of a right valve seat ( 4 - 1 ), a right cone valve core ( 4 - 2 ) and a right spring ( 4 - 3 ); and a conical surface of the right cone valve core ( 4 - 2 ) is closely attached to a right conical surface of the valve core ( 2 ) by the action of the right spring ( 4 - 3 );

wherein a left first central hole and a right first central hole ( 2 - 1 ) are disposed on the central line of the valve core ( 2 ); the two first central holes ( 2 - 1 ) are in communication with each other via a second central hole ( 2 - 2 ) which diameter is smaller than diameters of the two first central holes ( 2 - 1 ), and frustum holes ( 2 - 3 ) are respectively formed at junctions of the second central hole ( 2 - 2 ) and each of the first central holes ( 2 - 1 ); a left oil-feeding throttling groove ( 2 - 4 ) and a right oil-feeding throttling groove ( 2 - 5 ) are disposed between the sixth oil port (P) and the third oil port (I/M); a left throttling groove ( 2 - 6 ) is disposed between the first oil port (A) and the second oil port (I/L); a left oil-returning hole assembly composed of a left first throttling hole ( 2 - 7 ), a left second throttling hole ( 2 - 8 ) and a left third throttling hole ( 2 - 9 ) is disposed between the left oil port and the second oil port (I/L); the left second throttling hole ( 2 - 8 ) is in communication with the first oil port (A); a right throttling groove ( 2 - 10 ) is disposed between the fifth oil port (B) and the fourth oil port (I/R); a right oil-returning hole assembly composed of a right first throttling hole ( 2 - 11 ), a right second throttling hole ( 2 - 12 ) and a right third throttling hole ( 2 - 13 ) is disposed between the right oil port and the fourth oil port (I/R); and both the right second throttling hole ( 2 - 12 ) and the right third throttling hole ( 2 - 13 ) are in communication with the fifth oil port (B).

2. The energy-recycling hydraulic control main valve of claim 1 , wherein a left first circular groove ( 3 - 1 - 1 ), a left second circular groove ( 3 - 1 - 2 ), a left first seal groove ( 3 - 1 - 3 ) and a left second seal groove ( 3 - 1 - 4 ) are disposed on the circumference of the left valve seat ( 3 - 1 ), and a left valve seat central hole ( 3 - 1 - 5 ) is disposed on the central line of the left valve seat ( 3 - 1 ); the left first circular groove ( 3 - 1 - 1 ) is in communication with the left valve seat central hole ( 3 - 1 - 5 ) via two left valve seat radial holes ( 3 - 1 - 6 ) that are disposed radially; and each of the left first seal groove ( 3 - 1 - 3 ) and the left second seal groove ( 3 - 1 - 4 ) is provided with a left seal ring ( 3 - 1 - 7 ); and

a right first circular groove ( 4 - 1 - 1 ), a right second circular groove ( 4 - 1 - 2 ), a right first seal groove ( 4 - 1 - 3 ) and a right second seal groove ( 4 - 1 - 4 ) are disposed on the circumference of the right valve seat ( 4 - 1 ), and a right valve seat central hole ( 4 - 1 - 5 ) is disposed on the central line of the right valve seat ( 4 - 1 ); the right first circular groove ( 4 - 1 - 1 ) is in communication with the right valve seat central hole ( 4 - 1 - 5 ) via a right valve seat radial hole ( 4 - 1 - 6 ) that is disposed radially; and each of the right first seal groove ( 4 - 1 - 3 ) and the right second seal groove ( 4 - 1 - 4 ) is provided with a right seal ring ( 4 - 1 - 7 ).

3. The energy-recycling hydraulic control main valve of claim 2 , wherein a left spring hole ( 3 - 2 - 1 ) and a left cone valve core hole ( 3 - 2 - 2 ) that are in communication with each other are disposed on the central line of the left cone valve core ( 3 - 2 ), a left shoulder ( 3 - 2 - 3 ) with a radial circular surface is provided at the right end of the left cone valve core ( 3 - 2 ); a left shoulder radial hole ( 3 - 2 - 4 ) is disposed along a radial direction of the left shoulder ( 3 - 2 - 3 ), and the right end of the left shoulder ( 3 - 2 - 3 ) is provided with a left shoulder conical surface; the left shoulder radial hole ( 3 - 2 - 4 ) is in communication with the left cone valve core hole ( 3 - 2 - 2 ); and the angle of the left shoulder conical surface is smaller than the angle of the frustum holes; and

a right spring hole ( 4 - 2 - 1 ) and a right cone valve core hole ( 4 - 2 - 2 ) that are in communication with each other are disposed on the central line of the right cone valve core ( 4 - 2 ), a right shoulder ( 4 - 2 - 3 ) with a radial circular surface is provided at the right end of the right cone valve core ( 4 - 2 ); two right shoulder radial holes ( 4 - 2 - 4 ) are disposed along a radial direction of the right shoulder ( 4 - 2 - 3 ), and the right end of the right shoulder ( 4 - 2 - 3 ) is provided with a right shoulder conical surface; the right shoulder radial holes ( 4 - 2 - 4 ) are in communication with the right cone valve core hole ( 4 - 2 - 2 ); and the angle of the right shoulder conical surface is smaller than the angle of the frustum holes.

4. The energy-recycling hydraulic control main valve of claim 3 , wherein two left pressure-releasing slant holes ( 7 ) are disposed near the left oil port; and two right pressure-releasing slant holes ( 8 ) are disposed near the right oil port.