Automatically controlled magnetic minesweeping system
AssigneeThe United States of America as represented by the Secretary of the Navy
InventorHarold Lubnow
Life of this patent
Estimating the term…
Abstract
The invention is an automatically controlled magnetic marine mine sweeping ystem that does not constitute a safety hazard to the ship deploying it. It includes a ship that trails a pair of electrodes within the water which are, in turn, electrically energized by a variable current generator to induce a magnetic field therein. The intensity of said magnetic field is sensed by a magnetometer; and by means of a closed-loop, negative-feedback circuit incorporating said magnetometer, said current generator, and said sea water, the intensity of said magnetic field is limited to the extent that it does not extend under the ship and detonate marine mines that are close enough to be destructive thereto.
Claims18
A method of sweeping magnetically responsive marine mines to effect detonation of those thereof that are not located within destructive proximity of the minesweeping ship effecting the sweep thereof and to not effect detonation of those thereof that are located within destructive proximity of said minesweeping ship, comprising the combined steps of:
- generating a magnetic field within the water and sea floor where said magnetically responsive marine mines are suspected of being located;
- sensing the intensity of said magnetic field at a predetermined distance from said ship and producing a first signal proportional thereto;
- controlling the intensity of said sensed magnetic field to prevent it from extending close enough to said minesweeping ship to detonate a magnetically responsive marine mine that may be in destructive proximity therewith by comparing said first signal that is proportional to said sensed magnetic field with a preset second signal that is calibrated to be proportional to a known distance from said minesweeping ship and producing a third signal that is proportional in polarity and magnitude to the difference therebetween;
- integrating said third signal in accordance with a predetermined time constant;
- and automatically regulating the generating of the aforesaid generated magnetic field in accordance with the polarity and magnitude of said integrated third signal, so as to equalize said first and second signals.
A magnetic minesweeping system, comprising in combination:
- a tractor vehicle for traversing a predetermined course within a predetermined environmental medium;
- controllable means mounted on said tractor vehicle for generating an electric current;
- means connected to said electric current generating means for broadcasting said electric current through a portion of said environmental medium to induce a magnetic field therein that has an intensity that is proportional thereto;
- means adjustably, spatially disposed from said tractor vehicle for sensing the intensity of said magnetic field and for producing a first signal proportional thereto;
- calibrated adjustable means for producing a predetermined second signal that is proportional to a given distance between said tractor vehicle and the magnetic field sensed by the aforesaid magnetic field sensing means;
- means connected between the outputs of said magnetic field sensing means and said calibrated adjustable means for producing an error signal having a polarity and magnitude that is proportional to the amount said first signal is greater or less than said second signal, respectively;
- and
- means connected between the output of said error signal producing means and the control input of the aforesaid electric current generating means for the regulation thereof to substantially equalize said first and second signals in response to said error signal.
Dependencies are inferred from the claim text.