Patent ID: 8074810

Claim:
Apparatus for moving material relative to a floor of a basin, comprising: a first blade; a second blade; the first blade and the second blade being configured to be adjacent to each other; and a drive configured to simultaneously move each of the adjacent first and second blades relative to the floor of the basin, the drive configuration being to provide the simultaneous movement of each blade in opposition to the other blade; wherein the drive is configured with a first support for the first blade and a second support for the second blade, the supports being separate from each other; wherein the drive is further configured with at least one direction-reversal unit connected between the first and second supports; wherein the drive is further configured with a first pull-only driver connected to the first support and with a second pull-only driver connected to the second support; wherein the first support is configured as a first tensile member having a characteristic of transferring only tensile forces and the first pull-only driver only applies tensile forces to the first tensile member; wherein the second support is configured as a second tensile member having a characteristic of transferring only tensile forces and the second pull-only driver only applies tensile forces to the second tensile member; wherein each of the supports is configured with a first end and a second end; wherein the at least one direction-reversal unit is configured with at least one pulley, the at least one pulley being first and second separate pulleys; wherein the at least one direction-reversal unit is further configured with a third tensile member connected to the first end of the first support and extending around the first pulley and connected to the first end of the second support; wherein the at least one direction-reversal unit is further configured with a fourth tensile member connected to the second end of the first support and extending around the second pulley and connected to the second end of the second support; and wherein the first pull-only drivers is connected to the first support and the second pull-only driver is connected to the second support.