PURPOSE: To align and supply a required number of supply parts irrespective of the quantity of such supply parts remaining on a disk by rotating the disk at an optimum rotational frequency depending upon the quantity of such parts remaining on the disk.

CONSTITUTION: If a large quantity of supply parts are thrown on a disk 1, the quantity of such parts being moved increases to cause a signal from a sensor 8 to be made greater. Accordingly, an output of a differential arithmetic unit 11 decreases and an output of a motor controller 13 also decreases to reduce rotations of a motor 2 so that the disk 1 rotates at a slower speed and hence the quantity of the parts being moved from the disk 1 to an aligning track 3 is decreased thereby. The rotation of the motor 2 is controlled such that the quantity of the parts being moved actually is equal to a preset optimum quantity of such parts to be moved. Since those parts which are in a regular posture are taken out from an outlet port 6, the supply parts remaining on the disk 1 decreases accordingly and hence the quantity of the supply parts which move to the aligning track 3 also decreases. Accordingly, the signal from the sensor 8 is reduced to increase an output of a differential arithmetic unit 11 so that the motor 2 is accelerated by the motor controller 13 to thus raise the rotational speed of the disk 2.