An object of this invention is to provide a sealed rotary feeder for use in an apparatus which continuously processes chips made of synthetic resin with a coating under high pressure and temperature without degrading its material strength. The sealed rotary feeder according to this invention consists of a cylindrical casing having a chip inlet on the upper side of the cylindrical casing and a chip outlet on the low side of the cylindrical casing, a rotor in the cylindrical casing, plural blades which are movably inserted into channels radially formed around the rotor, and divide the cylindrical casing into plural baskets, pressing apparatus which press the plural blades against the inner surface of the cylindrical casing, and walls which form the channels are extended at the vicinity of the inner surface of the cylindrical casing.