System for controlling variable valve apparatus and oil control valve for the same

1. A system for controlling a variable valve apparatus, comprising:

a plurality of oil control valves (OCVs) configured to respectively supply oil from an oil pump to a plurality of variable valve apparatuses or block the supply of the oil; and

a single relief valve coupled to the plurality of oil control valves,

wherein pressure in a plurality of control galleries fir providing an oil supply path from the plurality of oil control valves to the plurality of variable valve apparatuses is maintained constant by only the single relief valve,

wherein the plurality of oil control valves is coupled with the single relief valve through a pressure control line, and when the supply of oil to the plurality of variable valve apparatuses is blocked, the plurality of control galleries is coupled with the pressure control line.

2. The system of claim 1 , wherein a drain hole for draining oil is formed in the single relief valve so that the pressure in the plurality of control galleries is reduced by draining oil from the plurality of control galleries through the drain hole, so that a difference in pressure between the plurality of control galleries and the drain hole remains constant.

3. The system of claim 2 , wherein, when the difference in pressure between the plurality of control galleries and the drain hole is greater than a spring force of the single relief valve, the single relief valve opens so that oil is drained through the drain hole.

4. The system of claim 3 , wherein, when a first flow passage from the plurality of control galleries to the plurality of variable valve apparatuses is opened by solenoid control, a second flow passage from the plurality of oil control valves to the pressure control line is blocked.

5. The system of claim 4 , wherein, when the supply of oil from the oil pump to the plurality of oil control valves is blocked by solenoid control, the first flow passage is blocked.

6. The system of claim 5 , wherein the plurality of variable valve apparatuses includes a 2-stage variable valve apparatus or a 3-stage variable valve apparatus.

7. The system of claim 3 , further including a single orifice provided on a return line coupling the pressure control line with a main gallery for providing a path of oil to be supplied from the oil pump to the plurality of oil control valves, so that the plurality of control galleries continues to be filled with oil by only the single orifice.

8. A system for controlling a variable valve apparatus, including:

a plurality of oil control valves (OCVs) configured to respectively supply oil supplied from an oil pump through a main gallery, to a plurality of variable valve apparatuses through a plurality of control galleries, or block the supply of the oil; and

a pressure control line coupled with the plurality of oil control valves and configured to control pressure in the plurality of control galleries; and

a single orifice provided on a return line coupling the main gallery with the pressure control line, so that the plurality of control galleries continues to be filled with oil by only the single orifice,

wherein, when the supply of the oil to the plurality of variable valve apparatuses blocked by the plurality of oil control valves, the plurality of control galleries is coupled with the pressure control line.

9. The system of claim 8 , wherein the pressure in the plurality of control galleries is reduced by draining oil from the plurality of control galleries through the pressure control line.

10. The system of claim 9 , wherein, when a first flow passage from the plurality of control galleries to the plurality of variable valve apparatuses is opened by solenoid control, a second flow passage from the plurality of oil control valves to the pressure control line is blocked.

11. The system of claim 10 , wherein, when the main gallery is blocked by solenoid control, the first flow passage is blocked.

12. The system of claim 11 , wherein the plurality of variable valve apparatuses includes a 2-stage variable valve apparatus or a 3-stage variable valve apparatus.

13. An oil control valve configured to supply oil from an oil pump to a variable valve apparatus through a control gallery or block the supply of the oil, wherein pressure of oil in the control gallery is configured to be controlled through a pressure control line coupled with a relief valve separately provided,

wherein, when a pintle operates a check ball by a solenoid to block a first flow passage from the control gallery to the variable valve apparatus, a hole coupled to the pressure control line opens so that the check ball is disposed at a position at which a second flow passage between the control gallery and the pressure control line opens.

14. The oil control valve of claim 13 , wherein, when the second flow passage opens, oil in the control gallery is drained through the pressure control line so that the pressure of the oil in the control gallery is reduced.

15. The oil control valve of claim 14 , wherein, when a difference in pressure between the control gallery and the pressure control line is a predetermined value or more, the oil in the control gallery is drained through the pressure control line.

16. The oil control valve of claim 15 , wherein, when the pintle operates the check ball by the solenoid to open the first flow passage, the check ball is disposed at a position at which the check ball closes the hole coupled to the pressure control line so that the second flow passage is blocked.

17. The oil control valve of claim 16 , wherein, when the pintle operates the check ball by the solenoid and thus the supply of the oil from the oil pump is blocked, the check hall is disposed at a position at which the first flow passage is blocked.