PROBLEM TO BE SOLVED: To simplify a structure and reduce a cost by dispensing with a dedicated storage position support member for supporting a detection body of a layer thickness sensor to a storage position.SOLUTION: A threshing part 3 comprises: an oscillating sorter 20 for sorting, while transferring processing materials from a threshing chamber 14, sieved through a receiving net 18 and a layer thickness sensor 34 for detecting the layer thickness of the processing materials being transferred on the oscillating sorter 20. The layer thickness sensor 34 includes: a detection body 35 freely turning according to the layer thickness of the processing materials a potentiometer 36 for detecting a turning position of the detection body 35 and a stopper member 37 that, when changing a state of the detection body 35 between a detection state of coming into contact with the processing materials and freely turning, and a storage state supported at a storage position, comes into contact with and supports the detection body 35 at an initial position of the detection state. The stopper member 37 is also served as a storage position support member for supporting the detection body 35 at the storage position.
