| 摘要 |
A vibrator seismic source for generation of seismic compression waves in a transmitting medium such as the earth's crust for mineral and oil exploration and other purposes consisting of an output member (5) for application to the transmitting medium to apply forces cyclically to it, the forces being generated by a piston (2) moving in a single acting hydraulic cylinder (1) to one end of which hydraulic liquid (7) under pressure is applied intermittently through a flow control valve (11). Preferably the flow control valve (11) is operated by means of an electrohydraulic servo valve (12) to which an alternating current of variable frequency is applied. |
