Device for receiving sound waves in a well

DETAILED DESCRIPTION The receiving device of the invention avoids the above mentioned disadvantages.
It is adapted to be associated with a probe lowered into a well or drill hole, at the end of a cable and able to be applied against the wall of the well by opening out anchoring arms, and comprises at least a receiver assembly and a hydraulic cylinder associated with pressure means for moving each receiver assembly between a retracted position and a position in which it is coupled with the wall of the well.
The device is characterized in that each receiver assembly is connected to the probe through resilient suspension means.
In a first embodiment of the device, the body of the cylinder is integral with the probe, at one end and the piston of the cylinder is connected to the receiving assembly through a sleeve adapted to slide over the body of the cylinder and a resilient suspension element comprising a tubular sheath having a section greater than that of the sleeve which defines with this latter and with the receiver assembly an annular chamber and the pressure means comprise a hydraulic system for operating the cylinder.
In a second embodiment, the sensor is integral with the piston of the cylinder, the body of this latter being connected to the probe by means of deformable connection elements.
In both cases, the interposed resilient connection elements considerably reduce the influence of the mass of the body of the probe on the frequency response curve of the sensor and the transmission to this latter of the parasitic vibrations.