Color sorting apparatus for beans

A color sorting apparatus for beans comprising:

• a transferring means for transferring beans to be sorted to a detection position, said transferring means including at least two endless belts defining therebetween a parallel gap on which said beans to be sorted are held in a single stream and a driving means for driving said two endless belts;
• an illuminating means for illuminating at said detection position said beans transferred by said transferring means, said illuminating means being provided above or below said parallel gap defined by said two endless belts;
• a light receiving means for receiving light transmitted through said bean and for outputting a detection signal, said light receiving means being provided at a position opposite to said illuminating means with said bean transferred by said transferring means being interposed therebetween;
• a control means for operating said detection signal, comparing the detection signal operated with a predetermined threshold value to determine whether said bean is a good bean or a defective bean, and outputting an ejection signal when said bean is determined to be a defective bean;
• a guide plate arranged under said two endless belts at said detection position, for stabilizing movement of said two endless belts and maintaining said parallel gap defined between said two endless belts to be constant, said guide plate being provided with at least one detection opening through which light passes, at a position corresponding to said detection position, and an exhaust opening for exhausting dust or dirt adhered on a surface of said bean to be sorted, at a position before said detection opening in a direction of movement of said two endless belts;
• a sucking means for sucking-in the dust or dirt adhered on the surface of said bean to be sorted, said sucking means being arranged to face said exhaust opening of said guide plate;
• and
• a sorting means for removing defective beans based on said detection signal.