Valve timing control device of internal combustion engine

摘要

Even if an internal combustion engine is stopped having a lock pin of a vane rotor kept disengaged from a lock recess, subsequent engine starting can instantly move the vane rotor to a desired angular position where the lock member an be engaged with the lock recess. The vane rotor has therein two passage control mechanisms each having a hydraulically actuated valve body. When the valve body is moved to a given position, retarding and advancing hydraulic holes become communicated to each other through an annular groove of the valve body. Due to this ON communication, retarding and advancing operation chambers become communicated, so that reciprocative swing movement of the vane rotor induced by an alternating torque produced at the starting of the engine is effectively made and thus the vane rotor can be quickly turned to the desired angular position for ease of engine starting.

主权项

1. A valve timing control device of an internal combustion engine, comprising:
an annular housing rotated by a crankshaft of the engine and having a plurality of shoes on a peripheral inner surface thereof, adjacent two of the shoes defining therebetween an operation chamber; a vane rotor connected to a camshaft of the engine to rotate therewith, the vane rotor being formed with vanes each dividing the operation chamber into an advancing operation chamber and a retarding operation chamber, the vane rotor being turned in an advancing or retarding direction relative to the annular housing when a hydraulic pressure is supplied to or discharged from the advancing and retarding operation chambers respectively; a first lock member provided by one of the vane rotor and the annular housing and movable toward and away from the other of the vane rotor and the annular housing with a driving force different from the hydraulic pressure supplied to the operation chambers; a second lock member provided by one of the vane rotor and the annular housing and movable toward and away from the other of the vane rotor and the annular housing with a driving force different from the hydraulic pressure supplied to the operation chambers; a first lock recess provided by the other of the vane rotor and the annular housing and suppressing, when engaged with the first lock member, at least turning of the vane rotor in a retarding direction from a position between the most advanced and most retarded angular positions; a second lock recess provided by the other of the vane rotor and the annular housing and suppressing, when engaged with the second lock member, at least turning of the vane rotor in an advancing direction from a position where the turning of the vane rotor in the retarding direction is suppressed due to engagement of the first lock member with the first lock recess; a communication passage provided by one of the vane rotor and the annular housing to communicate the advancing and retarding operation chambers; and a passage control mechanism that establishes the communication between the advancing and retarding operation chambers through the communication passage when the engine is stopped and reduces a cross sectional area of the communication passage when, after starting of the engine, the engine comes to show a predetermined speed or higher.