Patent ID: 7117910

Claim:
An air supply device for a rotating body having an air filling portion into which air is filled, comprising: a device body mounted on the rotating body and external of the air filling portion, the device body including a cylinder therein, a piston positioned within the cylinder and moveable along a longitudinal axis, wherein the piston is moved by a centrifugal force generated by rotation of the rotating body to supply air into the air filling portion, a pressure restricting means for restricting a maximum pressure in the air filling portion; and a latch disposed on an opposite side of the piston from the pressure restricting means and in selective engagement with the piston to define movement of the piston between the pressure restricting means and the latch; wherein the pressure restricting means adjusts a maximum distance of movement of the piston, and wherein the pressure restricting means comprises an adjusting screw movable along the longitudinal axis, which has a tip end adapted to abut against the piston and is screwed into the cylinder such that the maximum distance of movement of the piston is varied in accordance with the position of the screw along the longitudinal axis.