Valve opening/closing timing control apparatus

A valve opening/closing timing control apparatus comprising:

• a driving-side rotary body that is rotated in synchronism with a crank shaft of an internal combustion engine;
• a driven-side rotary body that is disposed coaxially with a rotational axis of the driving-side rotary body and that is rotated in synchronism with a cam shaft of the internal combustion engine;
• a fluid pressure chamber formed between the driving-side rotary body and the driven-side rotary body, and configured to change a relative phase between the driving-side rotary body and the driven-side rotary body by feeding/discharging of working fluid;
• a bolt member having a tubular portion that forms a passage for feeding/discharging the working fluid to/from the fluid pressure chamber and that is disposed inside the driven-side rotary body, the bolt member connecting the driven-side rotary body and the cam shaft;
• a valve body and a valve accommodating body that are disposed inside the tubular portion, the valve body being configured to regulate a flow direction of the working fluid relative to the fluid pressure chamber, the valve accommodating portion being configured to accommodate the valve body;
• a retainer that regulates a position of the valve accommodating body;
• an urging portion that urges the valve accommodating body;
• the tubular portion comprising a stepped portion that includes a radial base portion;
• and
• a space between the radial base portion and the retainer.