Asynchronous blueberry sorter

The present invention relates to a high speed asynchronous fruit sorter for sorting various types of fruits, such as blueberries, according to maturity. Forming a part of the fruit sorter is an open wire type conveyor having a generally M-shaped profile extending transversely across so as to define a series of laterally spaced and longitudinally extending conveying channels. An illumination source is disposed below the conveyor about an area referred to as a sorting zone. Disposed over the conveyor in the vicinity of the sorting zone is an optical maturity sensing device that continuously derives a differential optical density reading for the underlying passing fruit, and this differential optical density reading is directly related to the maturity of the fruit and is directed to a maturity discriminator circuit. The maturity discriminator circuit is in turn coupled to an air injection sorting apparatus by a series of AND gates. An optical asynchronous detector apparatus is positioned about the sorting zone and is adapted to detect the leading edge of oncoming articles of fruit and to actuate the AND gates at a selected time after detection in order that the air ejection system can be appropriately actuated to transfer certain maturity level grades to an adjacent area for receiving that particular maturity grade.