Chaff and straw spreading attachment for combines

In combination with an agricultural combine having a rearmost discharge for straw residue and a separate forwardly positioned discharge for chaff, apparatus for joining the discharged straw and chaff into a single stream and spreading the same behind the combine as the latter advances across a field, said apparatus comprising:

• a housing attached to said straw discharge and having an internal chamber,
• said chamber being provided with a straw inlet and an outlet at opposite portions thereof;
• a rotor located within said chamber between said inlet and outlet having an axis of rotation transverse to the path of travel of materials therethrough,
• said rotor having means thereon capable of impacting materials passing through the rotor during rotation of the latter and of creating a stream of air flowing through the chamber and out said outlet to entrain materials therein,
• said housing being provided with a second inlet to said chamber adjacent said straw inlet and remote from said outlet for receiving chaff from said chaff discharge and directing the same into said chamber for admixture with the straw, movement through the rotor, and entrainment in the stream flowing out said outlet;
• spreader means associated with said outlet in disposition for impinging the entrained materials issuing from said housing and dispersing the same laterally behind the advancing combine;
• a booster impeller adjacent said chaff discharge for producing a chaff-entraining current of air flowing to said chaff inlet of the rotor housing;
• an impeller housing about said impeller and provided with an outlet spaced from and oriented toward said chaff inlet of the rotor housing whereby to direct the air current to the rotor housing;
• and
• an open transfer space defined between the outlet of the impeller housing and the chaff inlet of the rotor housing,
• said open transfer space being exposed to the chaff discharge and said outlet of the impeller housing being physically separate from and unattached to the chaff inlet of the rotor housing whereby the air current moving through said transfer space and exposed to the chaff discharge may entrain the chaff and carry the same into the rotor housing.