A grain cleaning system for a combine harvester having a transmitter adapted to transmit a base signal at a known frequency and one or more spaced receivers for detecting signals of a different frequency as reflected from airborne grain and other materials within the duct of the grain cleaning system. An Electronic Control Unit modulates the base signal and the reflected signals to obtain Doppler signals or frequencies from which an average particle velocity is determined. The particle velocity is used as an input parameter for the generation of control signals for the adjustment of various working units of the combine harvester including, by way of example, the fan and sieves.

A grain cleaning system for a combine harvester having a transmitter adapted to transmit a base signal at a known frequency and one or more spaced receivers for detecting signals of a different frequency as reflected from airborne grain and other materials within the duct of the grain cleaning system. An Electronic Control Unit modulates the base signal and the reflected signals to obtain Doppler signals or frequencies from which an average particle velocity is determined. The particle velocity is used as an input parameter for the generation of control signals for the adjustment of various working units of the combine harvester including, by way of example, the fan and sieves.

A combine harvester includes threshing apparatus, a grain pan and a cleaning unit. The grain pan is arranged to collect a grain/chaff stream from the threshing apparatus and is driven in an oscillating manner to convey the collected grain/chaff to a rear edge from where the grain/chaff stream falls into the cleaning unit. The cleaning unit includes a fan unit for generating an airstream directed through the grain/chaff stream falling from the rear edge and an airstream vented above the grain pan.

A combine harvester includes threshing apparatus, a grain pan and a cleaning unit. The grain pan is arranged to collect a grain/chaff stream from the threshing apparatus and is driven in an oscillating manner to convey the collected grain/chaff to a rear edge from where the grain/chaff stream falls into the cleaning unit. The cleaning unit includes a fan unit for generating an airstream directed through the grain/chaff stream falling from the rear edge and an airstream vented above the grain pan.

The present invention provides an improved dust control system for removing debris and particulate matter from a fouled air stream. The system may be incorporated into crop harvesting equipment to eliminate the dust pollution generated by conventional harvesting equipment. The dust control system may use a multi-stage air filtering process that employs inertial separation techniques to eliminate particulate matter from the fouled air, without the need for water or electrostatic mechanisms to capture the fine particulates in the fouled air.

The present invention provides an improved dust control system for removing debris and particulate matter from a fouled air stream. The system may be incorporated into crop harvesting equipment to eliminate the dust pollution generated by conventional harvesting equipment. The dust control system may use a multi-stage air filtering process that employs inertial separation techniques to eliminate particulate matter from the fouled air, without the need for water or electrostatic mechanisms to capture the fine particulates in the fouled air.

Weed seeds are destroyed in the chaff from a combine harvester by repeated high speed impacts caused by a rotor which accelerates the discarded seeds in a direction centrifugally away from the rotor onto a stator including stator surfaces around the axis. Thus the discarded seeds rebound back and forth between the rotor and the stator to provide a plurality of impacts. A transfer auger at the rear edge of the combine sieve carries the weed seeds outwardly to respective weed seed destructors driven by the shaft of the transfer auger. The seeds are discharged radially through a discharge opening, where the angle of the discharge around the rotor axis can be changed to direct the seeds towards the guide fins of the tailboard of the chopper, or into the housing of the straw chopper.

A fan hub for an extractor for a harvesting machine that harvests a crop. The fan hub having a hub cover positioned along a rotation axis of a fan of the extractor. The hub cover is adjustable to alter the profile of the hub cover relative to the rotation axis.

Weed seeds are destroyed in the chaff from a combine harvester by repeated high speed impacts caused by a rotor mounted in one of a pair of side by side housings which accelerate the discarded seeds in a direction centrifugally away from the rotor onto a stator including angularly adjustable stator surfaces around the axis. Thus the discarded seeds rebound back and forth between the rotor and the stator to provide a plurality of impacts. The seeds are carried axially of the rotor by a controlled airstream so that they move to an axial discharge location where a discharge fan is mounted. The angle of the discharge around the rotor axis can be changed to direct the seeds to the side of the combine away from a straw chopper, towards the guide fins of the tailboard of the chopper, or into the housing of the straw chopper.

Weed seeds are destroyed in the chaff from a combine harvester by repeated high speed impacts caused by a rotor mounted in one of a pair of side by side housings which accelerate the discarded seeds in a direction centrifugally away from the rotor onto a stator including angularly adjustable stator surfaces around the axis. Thus the discarded seeds rebound back and forth between the rotor and the stator to provide a plurality of impacts. The seeds are carried axially of the rotor by a controlled airstream so that they move to an axial discharge location where a discharge fan is mounted. The angle of the discharge around the rotor axis can be changed to direct the seeds to the side of the combine away from a straw chopper, towards the guide fins of the tailboard of the chopper, or into the housing of the straw chopper.