| 摘要 |
PURPOSE:To prevent the staying and consolidation of soil in a double cylinder consisting of a front cylinder and a rear cylinder by a method in which a mud water supplier and a mud water discharger are connectedly provided in the space between the front cylinder and rear cylinder of an expandible excavator. CONSTITUTION:When a space B between a front cylinder 1 and a rear cylinder 2 is increased as the cylinder 1 goes forward, a mud water pump 19 is operated to supply mud water in a mud water tank 21 into the space B through the pump 19 and a check valve 22. When the space B between the cylinders 1 and 2 is decreased as the cylinder 2 advances, the pump 19 is stopped. Afterwards, a partition valve 20 is opened to return mud water in the space B to the tank 21 through the valves 22 and 20. |
