Valve timing control apparatus

A valve timing control apparatus for an engine, comprising:

• a driving side rotational member rotating synchronously to a crankshaft;
• a driven side rotational member arranged coaxially to the driving side rotational member to be relatively rotatable and rotating integrally to a camshaft;
• a fluid pressure chamber formed between the driving side rotational member and the driven side rotational member and defined into an advanced angle chamber and a retarded angle chamber;
• a relative rotational phase adjusting mechanism controlling to selectively supply and drain a working fluid to and from the advanced angle chamber and the retarded angle chamber and adjusting a relative rotational phase of the driving side rotational member and the driven side rotational member between a most advanced angle phase where a volume of the advanced angle chamber is maximized and a most retarded angle phase where the volume of the advanced angle chamber is minimized;
• and
• a one-way valve provided at a passage introducing an outside air to the advanced angle chamber and the one-way valve allowing communication from an outside of the fluid pressure chamber to the advanced angle chamber to introduce the outside air to the advanced angle chamber and blocking the communication from the advanced angle chamber to the outside of the fluid pressure chamber.

A valve timing control apparatus for an engine, comprising:

• a driving side rotational member rotating synchronously with a crankshaft;
• a driven side rotational member coaxial with the driving side rotational member to be relatively rotatable and rotating integrally to a camshaft;
• a fluid pressure chamber between the driving side rotational member and the driven side rotational member, the fluid pressure chamber being divided into an advanced angle chamber and a retarded angle chamber;
• a retarded angle oil passage fluidly communicating with the retarded angle chamber;
• an advanced angle oil passage fluidly communicating with the advanced angle chamber;
• a relative rotational phase adjusting mechanism controlling selective supply and drain of a working fluid to and from the advanced angle chamber and the retarded angle chamber and adjusting a relative rotational phase of the driving side rotational member and the driven side rotational member between a most advanced angle phase where a volume of the advanced angle chamber is maximized and a most retarded angle phase where the volume of the advanced angle chamber is minimized;
• and
• a communicating passage communicating the advanced angle chamber to outside the fluid pressure chamber, the communicating passage being different from the retarded angle oil passage and the advanced angle oil passage;
• a valve positioned in the communicating passage and comprising a movable member movable to one position allowing air outside the fluid pressure chamber to be introduced into the advanced angle chamber by way of the communicating passage when a fluctuated torque generated at the camshaft exceeds a torque applied to the driven side rotational member by the relative rotational phase adjusting mechanism.