Fixing apparatus and image forming apparatus

A fixing apparatus comprising:

• a first rotary member configured to rotate around a first shaft;
• a second rotary member disposed so as to come into contact with and separate from the first rotary member, and configured to form a nip portion with the first rotary member;
• a heater configured to heat the nip portion;
• a frame comprising a pair of side plates;
• a pressing member supported by the pair of side plates, and configured to press the second rotary member, wherein the pressing member is configured to be movable between a first position, where a distance between center positions of the first rotary member and the second rotary member is a first distance, and a second position, where the distance between the center positions of the first rotary member and the second rotary member is a second distance which is larger than the first distance;
• an urging member configured to urge the pressing member toward the first position;
• a second shaft supported by the pair of side plates so as to be attachable to and detachable from the pair of side plates;
• and
• a cam rotatably supported by the second shaft, and configured to change a position of the pressing member between the first position and the second position,
• wherein each of the pair of side plates comprises an opening portion which is disposed at an edge of each of the pair of side plates and into which the second shaft enters, and a bearing groove which communicates with the opening portion,
• wherein the bearing groove comprises a receiving portion which receives an urging force which the second shaft receives from the urging member via the pressing member and the cam in a state where the second shaft is supported by the pair of side plates, and
• wherein the receiving portion is disposed at a position which is farther apart from the pressing member than the opening portion in an urging direction of the urging member when viewed in an axial direction of the first shaft.