A damper restricts pivot pin rotation associated with operation of an operating section, wherein friction resistance that impedes the pivot pin rotation is changed in stepped fashion. When the pivot pin rotates in direction α due to depression of an accelerator pedal, a slide cam shifts an edge section of an inclined cam surface away from a rotating cam while staying in contact with a gradual first inclined region of the rotating cam's inclined cam surface. Torque around the axis of the pivot pin is produced, the entire region of the slide cam's inclined cam surface comes into contact with a steep second inclined region of the rotating cam's inclined cam surface upon accelerator pedal depression to a prescribed position (the pivot pin has rotated by a prescribed angle θ1 in direction α), and the torque around the axis of the pivot pin rapidly increases.