Abstract: A grain cleaning apparatus (10) for removing coarse and fine foreign materials from dirty grain before storage. The grain cleaning apparatus includes counter-rotating screen drums (18,20). Dirty grain is received in a frusto-conically shaped inner drum (18). Coarse foreign materials are prevented from passing through screen (100) of inner drum (18) and rather move to chute (38) where they fall to trough (40) for exiting from apparatus (10). Chute (38) is located between the output end (36) of the inner drum (18) and the output end (48) of the cylindrical outer drum (20). Grain is prevented from passing through screen (115) of outer drum (20). Fine foreign materials do pass therethrough, however, for exiting from apparatus (10). Clean grain drops from the output end (48) of outer drum (20).A motor (22) drives a secondary drive shaft (24). Shaft (24) drives first and second pulley systems (26,28) to rotate inner and outer screen drums (18,20) in opposite directions simultaneously.

Abstract: A control system for a grain drying bin includes a pre-dry sensor mounted on the inside of a grain drying bin a short distance above the floor and a thermocouple grain temperature sensor mounted in the discharge tube of the grain drying bin. The discharge grain temperature sensor includes a thermal contact member made of copper or other heat conductive material having a thermocouple bonded thereto to intimate heat conducting relationship. The thermal contact member is mounted by a mounting block to the discharge tube to extend through a slot into the interior of the tube and is shaped to allow the grain to flow around it in thermal contact therewith. A gap is provided in the fighting of the discharge auger in order to provide clearance for the thermal contact member. The control system prevents discharge of grain until the pre-dry temperature is attained, and controls stopping of the grain discharge, in either a sample mode or a discharge mode, if the discharged grain is too cool.