Patent ID: 8385784

Claim:
A development station comprising: a housing having an opening to receive toner and a development window through which a developer can be exposed to an electrostatically charged member such that toner will transfer to the electrostatically charged member according to the electrostatic charge thereon and providing a recirculation path from the development window through an area where toner from the opening can be added to developer in the housing including developer from the development window and returning to the development window and an auger positioned within the housing and being rotatable to move the developer along at least part of the recirculation path; a first actuator driving a first end of the auger; a second actuator driving a second end of the auger; a first sensor for sensing a condition from which a rotational position of the first end of the auger can be determined and generating a first sensor signal from which the rotational position of the first end of the auger can be determined; and a second sensor for sensing a condition from which a rotational position of a second end of the auger can be determined and generating a second sensor signal from which the rotational position of the second end of the auger can be determined; and an auger controller receiving the first sensor signal and the second sensor signal and generating a first control signal causing the first actuator to operate so that a first force is applied to the first end of the auger and generating a second control signal causing the second actuator to operate so that a second force is applied to the second end of the auger together to rotate the auger against a drag created by the developer, wherein the auger controller causes both the first force and the second force to be less than a third force that is sufficient to drive an alternative auger against the drag from one driven end and wherein the auger has a first yield strength at the first end and a second yield strength at the second end that are each less than a third yield strength that is required to receive the third force at the driven end of the alternative auger.