Elastic-wave sensor electrically compensated for the effects of inclination

摘要

A sensor assembly has an electrodynamic sensor with a device generating a magnetic field, a moving coil within this field and springs maintaining the coil in a central position when its axis is parallel to a reference direction. A current is applied to the coil to compensate for all disequilibrium caused by inclination of the coil axis relative to the reference direction. Independent claims are included for the following: (a) the use of the above device to compensate for inclination of a geophone in an angle borehole; and (b) the use of the above device to compensate for inclination of a geophone resting on the sea floor. Preferred Features: The current comes from a continuous current source via a potentiometer whose output depends upon the angle between the sensor axis and the reference direction.