Chain tensioner

A chain tensioner comprising:

• a lever including a sliding contact surface, which is configured to come into sliding contact with a chain, and a boss portion;
• and
• a torsion coil spring including a coil portion fitting into the boss portion, a fixed-side support arm extending from one end of the coil portion, and a lever-side support arm extending from the other end of the coil portion, wherein
• the lever-side support arm abuts against a contact surface provided on the lever to apply a biasing force of the torsion coil spring to the lever and apply tension to the chain via the sliding contact surface,
• the fixed-side support arm, includes
• a holding portion extending in an axial direction of the coil portion and configured to hold the fixed-side support arm with respect to a contact portion which is a fixing member by abutting against the contact portion,
• a locking portion, and
• a pressing portion extending in a direction intersecting with an extending direction of the holding portion,
• the lever includes a spring housing portion that houses the locking portion, and an engaging portion that locks the locking portion housed in the spring housing portion in a state in which a biasing force is applied, and
• a pressing force is applied to the pressing portion so that the locking portion is removed from the spring housing portion and the locking with the engaging portion is released.