Valve opening-closing timing control apparatus

Abstract

A valve opening-closing timing control apparatus includes an intermediate phase retaining mechanism retaining the relative rotational phase of a driven-side rotational member relative to the driving-side rotational member at an intermediate phase that is a phase between most retarded angle phase and most advanced angle phase. The driving-side rotational member synchronously rotates with a crankshaft of an internal combustion engine. The driven-side rotational member integrally rotates with a camshaft of the internal combustion engine and makes relative rotations relative to the driving-side rotational member. The valve opening-closing timing control apparatus further includes a state variable acquisition portion acquiring a state variable relating to the internal combustion engine and a phase controller displacing the relative rotational phase to the intermediate phase on condition that the relative rotational phase is at a retarded angle phase at a time at which the internal combustion engine stops and the state variable satisfies a predetermined condition.

1 . A valve opening-closing timing control apparatus, comprising:
 a driving-side rotational member configured to synchronously rotate with a crankshaft of an internal combustion engine;   a driven-side rotational member configured to integrally rotate with a camshaft of the internal combustion engine and makes relative rotations relative to the driving-side rotational member;   a fluid pressure chamber formed by the driving-side rotational member and the driven-side rotational member;   a vane arranged in the fluid pressure chamber to partition the fluid pressure chamber into a retarded angle chamber and an advanced angle chamber, the retarded angle chamber configured to move relative rotational phase of the driven-side rotational member relative to the driving-side rotational member in a retarded angle direction that is one direction of the relative rotations and the advanced angle chamber configured to move the relative rotational phase in an advanced angle direction that is another direction of the relative rotations;   an intermediate phase retaining mechanism retaining the relative rotational phase at an intermediate phase that is a phase between most retarded angle phase and most advanced angle phase;   a state variable acquisition portion acquiring a state variable relating to the internal combustion engine; and   a phase controller displacing the relative rotational phase to the intermediate phase on condition that the relative rotational phase is at a retarded angle phase relative to the intermediate phase at a time at which the internal combustion engine stops and the state variable satisfies a predetermined condition.   
     
     
         2 . The valve opening-closing timing control apparatus according to  claim 1 , wherein
 the state variable acquisition portion acquires at least one of temperature of oil flowing in the internal combustion engine, temperature of a cooling medium for cooling the internal combustion engine, and temperature of air taken into the internal combustion engine as the state variable, and wherein   the phase controller displaces the relative rotational phase to the intermediate phase on condition that temperature acquired as the state variable is equal to or less than a predetermined temperature for each of the state variables.   
     
     
         3 . The valve opening-closing timing control apparatus according to  claim 1 , wherein
 the state variable acquisition portion acquires an elapsed time relative to a point in time at which the internal combustion engine is stopped as the state variable and wherein   the phase controller displaces the relative rotational phase to the intermediate phase on condition that the elapsed time acquired as the state variable by the state variable acquisition portion becomes equal to or greater than a predetermined elapsed time.   
     
     
         4 . The valve opening-closing timing control apparatus according to  claim 1 , wherein
 the phase controller displaces the relative rotational phase to the intermediate phase while the internal combustion engine is at a stop.   
     
     
         5 . A valve opening-closing timing control apparatus, comprising:
 a driving-side rotational member configured to synchronously rotate with a crankshaft of an internal combustion engine;   a driven-side rotational member configured to integrally rotate with a camshaft of the internal combustion engine and makes relative rotations relative to the driving-side rotational member;   a fluid pressure chamber formed by the driving-side rotational member and the driven-side rotational member;   a vane arranged in the fluid pressure chamber to partition the fluid pressure chamber into a retarded angle chamber and an advanced angle chamber;   the retarded angle chamber within which a volume increases in a case where a relative rotational phase of the driven-side rotational member relative to the driving-side rotational member moves in a retarded angle direction that is one direction of the relative rotations;   the advanced angle chamber within which a volume increases in a case where the relative rotational phase moves in an advanced angle direction that is a different direction from the retarded angle direction;   an intermediate phase retaining mechanism retaining the relative rotational phase at an intermediate phase that is a phase between most retarded angle phase and most advanced angle phase where the most retarded angle phase is a phase at which the volume within the retarded angle chamber is at maximum and the most advanced angle phase is a phase at which the volume within the advanced angle chamber is at maximum;   a state variable acquisition portion acquiring a state variable relating to the internal combustion engine; and   a phase controller displacing the relative rotational phase to the intermediate phase on condition that the relative rotational phase at a time at which the internal combustion engine stops is at a position closer to the most retarded angle phase relative to the intermediate phase and the state variable acquired by the state variable acquisition portion satisfies a predetermined condition.