Remotely operated magnetic release for anchored aquatic instrumentation

Abstract

A latch mechanism (release) for use in anchoring equipment and devices submerged in water, held closed by a permanent magnet and which can be automatically or remotely opened by diverting the magnetic field. The release is held closed by the magnetic attraction between a permanent magnet and a plate on a lever arm whose movement effects closure of the latch. A spring acts to move the lever arm and open the latch but the magnet normally overwelms it. The latch opens when a brief electromagnetic field is applied to a soft magnetic alloy which guides magnetic flux from the magnet to the plate on the latch. The brief electromagnetic field weakens the attraction between the magnet and the plate by diverting the magnetic flux through an alternate loop in the alloy material, and thus allows the spring on the lever arm to open the latch. The release is triggered by acoustic signals transmitted to it and which are processed by an internal acoustic transducer and electronic controller which, upon receipt of appropriate acoustic signals, supplies electrical current to a coil surrounding the magnetic alloy material. The release mechanism has a low power requirement, is simple and yet is strong when closed.