Abstract: A soil spreading scraper device comprises a cutting blade for cutting a top layer of soil from the ground, a kicker for throwing the cut soil rearward from the cutting blade, and an impeller member rotatable within a plane of rotation extending upward and rearward from the cutting blade for capturing the soil thrown by the kicker and spreading the cut soil generally radially outward relative to an axis of rotation of the impeller. A gearbox which receives power from a power takeoff of a towing vehicle directly drives the rotation of the impeller member in the preferred embodiment. The blades of the impeller members may include recessed portions adjacent the impeller axis in some embodiments to encourage soil being received in the impeller member even at higher rates of rotation, for example in the range of 250 to 320 RPM.

Abstract: A soil spreading scraper device comprises a cutting blade for cutting a top layer of soil from the ground, a kicker for throwing the cut soil rearward from the cutting blade, and an impeller member rotatable within a plane of rotation extending upward and rearward from the cutting blade for capturing the soil thrown by the kicker and spreading the cut soil generally radially outward relative to an axis of rotation of the impeller. A gearbox which receives power from a power takeoff of a towing vehicle directly drives the rotation of the impeller member in the preferred embodiment. The blades of the impeller members may include recessed portions adjacent the impeller axis in some embodiments to encourage soil being received in the impeller member even at higher rates of rotation, for example in the range of 250 to 320 RPM.

Abstract: A wafer position error detection and correction system determines the presence of a wafer on a wafer transport robot blade. The system also determines a wafer position error by monitoring the position of the wafer with respect to the blade with one sensor which is located proximate to each entrance of a process chamber. When a wafer position error is detected, the system determines the extent of the misalignment and corrects such misalignment if correctable by the wafer transport robot or alerts an operator for operator intervention. The system incorporates a transparent cover on the surface of the wafer handling chamber and four optical detection sensors disposed on the surface of the transparent cover, in which each sensor is placed proximate to the entrance of the process chamber. In addition, an I/O sensor is placed adjacent the I/O slit valve to detect and correct wafer position errors.