Variable flow rate valve mechanism and turbocharger

A variable flow rate valve mechanism which opens and closes an opening of a variable gas flow rate passage, the variable flow rate valve mechanism comprising:

• a valve body which opens and closes the opening;
• a stem which is rotatably supported by a housing while the valve body is connected to a first end thereof;
• a cylindrical bearing which is inserted through a through-hole of the housing and rotatably supports the stem about an axis line of the stem;
• a link member which is connected to a second end of the stem;
• and
• a spring mechanism which is disposed in a gap between the link member and an end of the bearing, on the side of the second end,
• wherein the end of the bearing includes an inclined surface which contacts the spring mechanism and is inclined with respect to the axis line of the stem, and
• wherein the spring mechanism includes a flange portion which contacts the link member while protruding outward in the radial direction of the bearing at the second end side in the axial direction of the stem.