Valve timing adjustment device

A valve timing adjustment device configured to adjust valve timing of a valve in an internal combustion engine, the valve being configured to be selectively opened and closed by a driven shaft to which a driving force is transmitted from a drive shaft, the valve timing adjustment device comprising:

• a vane rotor that is fixed to an end portion of the driven shaft, that is configured to rotate together with the driven shaft, and that is configured to alter a phase of the driven shaft relative to the drive shaft according to a pressure of a hydraulic oil supplied from a hydraulic oil supply source, the vane rotor defining a through hole passing through the vane rotor in an axial direction;
• a hydraulic oil control valve that is configured to perform a flow control of the hydraulic oil, the flow control including a control to supply the hydraulic oil to the vane rotor and a control to discharge the hydraulic oil from the vane rotor, the hydraulic oil control valve including:
• a tubular sleeve that includes a body portion disposed in the through hole and a fixing portion inserted and fixed into a shaft fixing hole, the shaft fixing hole being defined in the end portion of the driven shaft;
• and
• a spool that is configured to slidably move in the axial direction within the sleeve, wherein
• at least a portion of the through hole in the axial direction is sealed by the body portion,
• a difference between a radial dimension of the shaft fixing hole and a radial dimension of the fixing portion is greater than a total of a predetermined coaxiality between the through hole and the shaft fixing hole and a predetermined coaxiality between the body portion and the fixing portion, and
• the total is greater than zero.