PURPOSE: To properly discharge material inside a feeder by mounting a swing ring at the upper supply port and operating the swing ring to destroy the block of material choked at the supply port.

CONSTITUTION: A supply port 2 is formed at the upper part of a feeder body 1 and a discharge port is formed at the lower part. A rotor having vanes 4 around it is mounted inside the feeder body 1 to define separated spaces 6 between the feeder body 1 and the rotor 5. A swing ring 7 is mounted at the supply port 2 and the shaft 8 of the swing ring 7 has a swing handle 9. When the swing handle 9 is swung to the left and the right manually, the swing ring 7 is swung up and down so that the material choked at the supply port 2 is destroyed and discharged properly.