| 摘要 |
PURPOSE:To detect the position of a buried pipe, which has been provided, without the damage, by providing a high-pressure fluid injection nozzle for ditching and a pair of probing bars moving a ditch on a freely running mobile truck. CONSTITUTION:A mobile truck 1 is so placed that it runs freely in the direction where a new pipe should be buried, and the height of an injection nozzle 5 is adjusted by a cylinder jack 4, and the truck is run while jetting a high pressure fluid from the injection nozzle 5 through a high pressure holse 6. As the result, only earth and sand are digged up to form two ditches, and the position of a table 7 is controlled by a cylinder 8 for table ascent and descent, and the inside of the ditches is investigated by a pair of probing bars 18 placed in ditches. If a buried pipe or the like exists in ditches, probing bars 18 are brought into contact with it, and a turning arm 10 is drawn by frictional resistance, and a limit switch 11 is turned on. The table 7 and probing bars 18 are drawn up through a control device 17, thus confirming the position of the buried pipe. |
