| 摘要 |
PURPOSE: To automatically, precisely and rapidly measure penetration depth of a cone into the ground connected to a tip of a rod without suspending the penetrating operation of the rod. CONSTITUTION: Relating to the corn with built-in various sensors, specified length of a plurality of rods are connected together in turn, as they are penetrated into the ground. Near the penetration pass for the rod, a joint detecting sensor 20, having a coil 20e which is, when the connection parts of the plurality of rods penetrated into the ground pass, affected by change in magnetic flux so that pulse-like un-equilibrium voltage is induced in a bridge circuit, is provided. On the pulse signal, processes such as detecting, waveform process, and amplification, etc., are performed by a channel circuit CH1, and further, the signal is converted into digital signal by an A/D converter 29, and then inputted into a signal process means 30, and counted by a counter 30g, thus the depth in unit of rod length is measured. penetration quantity less than the unit length of rod is measured with a laser displacement meter 24. |
