| 摘要 |
Apparatus for transporting a material such as concrete utilizes a flexible duct connected to a hopper and includes a device that can pinch the duct. The pinching device has first and second pinch members that are movable transversely relative to the duct, and a drive member situated between the pinch members and likewise movable transversely to the duct. The apparatus also has an air injector, and a controller for timing the injection of air and the movements of the pinch and drive members so as to drive the material in the flexible duct.
|
