To solve such a problem that electrified plastic is sorted erroneously when the electrified plastic is made to fall in an electric field-applied area since the initial falling rate of the electrified plastic is accelerated, the time that the electrified plastic receives the electrostatic force from an electric field becomes short and the triboelectric charge quantity of the electrified plastic becomes small.
The subject electrostatic sorting apparatus is constituted so that two or more kinds of electrified granular substances are separated by the electrostatic force from the electric field according to the positively/negatively electrified charge amounts of them by making them fall between two pieces of electrodes which are arranged face to face and to which the electric field is applied. This apparatus is provided with: a conveying unit 2 having a conveying route 22 at the tip of which a falling part 24 is formed and which consists of an electrically insulating material for conveying the electrified granular substances uniformly in the direction of the falling part and a drive source for vibrating the conveying route 22; a first electrode 4a which is arranged just under the falling part of the conveying unit and extended in the falling direction; and a counter electrode 4b being a second electrode which is arranged in front of the falling part of the conveying unit, opposed to the first electrode and charged positively or negatively contrary to the first electrode.
MOROKUMA HIRONORI
Masuo Oiwa
Toshihide Kodama
Keigo Murakami