Work piece feeding machine and abrasive system

A work piece feeding machine, which sets a work piece into a through-hole of a carrier and feeds the carrier holding the work piece to a machine for further treatment, comprising:

• a loading unit for feeding the work piece to the through-hole of the carrier;
• and
• a positioning unit detecting amount of displacement of the work piece with respect to the through-hole at a detecting position and correcting the position of the work piece in the through-hole on the basis of the detected amount of the displacement thereof,
• wherein the positioning unit includes:
• a lighting source section being provided on the work piece side or the carrier side, the lighting source section throwing polarized light on the work piece and the carrier at the detecting position;
• a camera being provided on the carrier side or the work piece side, the camera receiving the polarized light from the lighting source section with selecting a polarizing direction so as to catch images of an outer edge of the work piece and an inner edge of the through-hole in a visual field thereof;
• and
• an image processing section measuring the amount of displacement of the work piece with respect to the through-hole on the basis of positions of the outer edge of the work piece and the inner edge of the through-hole in the visual field.