US 3822403 A
Apparatus and method for electromagnetically repelling elasmobranchii, such as sharks and the like, wherein an electric circuit, including a timing circuit, a plurality of spaced electrodes and a source of electrical energy, is connected in a housing and is energized upon submergence of said electrodes in a body of water, said electric circuit including means for rapidly pulsing a direct current between said electrodes to generate an electromagnetic field in the body of water to repel said sharks and the like.
Claims available in
Description (OCR text may contain errors)
1 c anv eci lrve v 1 g- United 1 X S7 7 (Q [111 3,822,403 Coleman et y 1 J 1 '2, 1974 i v ',,j. ;,a. 1 APPARATUSEAND METHOD FOR 3,164,172 H1965 Hicks 325/118 3,354.395 1l/1967 Merck et a1. 325/116 REPELLING SHARKS AND THE LIKE 3,559,161 l/l97l Raudsep 340/5 X Inventors: Robert n; Robert 3,683.280 8/1972 11011 325/118 x Hicks, 1 Asturia Ave., both of V Coral Gables 33134 Primary Examiner-Benedict V. Safourek  Assignee: said Hicks, by said C l Attorney, Agent, or Firm-Shoemaker & Mattare [221 F1lcd: Sept. 27, 19.71  ABSTRACT ] Appl' 184ll5 Apparatus and method forelectromagnetically repelling elasmobranchii', such as sl lggks and the like,  U5. C1 325/28, 119/3, 325/ e e n an t c t, including a m gci cu t,  Int. Cl A01k 61/00 a p r y of spaced electrodes and a source of elec-  Field of Search 61/70; 32s/1;'307/10; trical energy, is connected in ahousing and is ener- 331/55, 173; 325/1 16, 118; 219/67; 119/3; gized upon submergence of said electrodes in a' body I 325/156 180;. 340/4 R, 4 A, 4 C of water, said electric circuit including means for rapv idly pulsing a direct current between said electrodes to [5 6] Reference Cit d generate an electromagnetic field in the, body'of water i t0 repel said sharks and the 1,863.518 6/1932 Young 325/180 x i 9 Claims, 7 Drawing Figures PATENTEDJuL 2 m4 sum 1 m 2 INVENTOR5 ROBERT E. COLEMAN 8 ROBERT F. HICKS ATTORNEYS Byaggww M SHEET 2 BF 2 FIG. 7.
FIG 6 55.? 5 5 2;: *5
INVENTORS ROBERT E. COLEMAN 8K ROBERT F. HICKS M W/M/J Mm ATTORNEYS APPARATUS AND METHOD FOR REPELLING SHARKS ANDTHE LIKE BACKGROUND OF THE INVENTION has proven to be entirely satisfactoryor reliable in operation. Such prior art devices have included various chemicals, or various devices for creating an electric field in a body of water, or even various colors applied to liferafts and vests and the like, which colors have been found to be less attractive to sharks and the like than other colors commonly used on rescue equipment used by persons in bodies of water. One prior art'device for creating an electric field in a body of water to repel sharks or the like generates electromagnetic waves in the body of water through the use of a dipole'antenna connected in a circuit selectively energized by a manually operated switch; and accordingly, the devicewill not operate unless the person using the device is conscious or remembers to turn it on. Moreover, the antenna used to generatethe electromagnetic waves may obstruct normal movement of the person wearingthe device,'an d it does'not surround the person with an electromagnetic field, but leavesnullzones through which a 'shark or the like might approach the person.
In the present invention, the circuit is automatically energized when it is submerged in abody of water and accordingly does not rely'upon the person using the device to turn it on. Moreover, alternating electromag-, netic fields are created by a plurality of electrodes connected in a timing circuit, and accordingly the null zone associated with each electromagnetic field is covered by the otherelectromagnetic field.
According to one aspect of the invention, three electrodes are arranged in a, triangular pattern in such a manner'as to create two electromagnetic fields substantially perpendicular to'one another and alternately energized such as to cover or eliminate the null zones commonly associated with an electric field to thereby preclude any possibility ofashark or the like approachand the like wherein a plurality of electrodes-are connected in an electrical circuit which is automatically energized upon the electrodes being submerged in a body of water.
A further object of this invention is to provide a means and method for electromagnetically repelling sharks and the like wherein three electrodes are connected in a circuit and are arranged in a triangular pattern such'as to create two electromagnetic fields disposed substantially perpendicularly to one another in a manner to effectively eliminate the null zone associated with each electric field.
BRIEF, DESCRIPTION OF THE DRAWINGS FIG. 3 is a schematic wiring diagram of the first form of the invention.
FIG. 4 is a diagrammatic view of the electric fields ,produced'with the embodiment of the invention shown in-FIGS. 1 through 3.
FIG. 5 is a view in section of a second form-of the invention.
FIG. 6 is a schematicwiring diagram of the form of theinvention shown in FIG. 5.
ing theperson using the device through an area which does not contain any electromagnetic radiation.
' The device according to the present invention does not present any danger or disc omfort to the person using the device since it does not rely upon voltage to repel the sharks or the like but rather generates electromagnetic radiation which stimulates the nervous system of sharks or the like to repel them in a manner more fully explained in US. Pat. No. 3,164,772.
The device of the present invention may be'wom upon the bod of a person or attached to a boat or other object or it may be used in a fixed installation, if desired.
OBJECTS OF THE INVENTION It is an object of this invention to provide a means and method for electromagnetically repelling elasmobranchii such as sharks and the like without disturbing other aquatic life.
Another object of this invention is to provide a means and method for electromagnetically repelling sharks FIG. 7 isa diagrammatic view. of the electric field produced with the'embodiment of the in FIGS. Sand 6.
DETAILED DESCRIPTION OF THE INVENTION Referring nowto thedrawings, wherein like refer-- A ence numerals refer to like'parts throughout the several views, a swimmer l isshown in FIG/1 with a repeller device 2 according to the present invention'suitably afixed thereto as by a strap 3 or the like connected with the repeller and disposed around the body of the person 1. A shark 4 is shown turning away from the swim-' mer due to the electromagnetic field set up around the swimmer by the repeller 2.
Referring now to FIG. -2, the repeller device 2 is shown in' its preferred form and includes a tubular housing comprised of a first elongate portion 5 and a second elongate portion 6 extending at right angles from the mid-portion of the portion 5. The housing may be constructed of any suitable material and is preferably constructed of polyvinyl chloride pipe having a diameter of approximately three-fourths of an inch. The
portion 5 would have a length, for example, on theorder of 14 inches. A pair of brass electrodes 7 and 8 are threaded into the opposite ends of portion 5, and a third brass electrode 9 is threaded into the free end of portion 6. The electrodes 7, 8 and 9 may be formed of other suitable materials capable of withstanding the corrosive environment of saltwater and may be affixed to the housing by other suitable means rather than the threaded connection shown.
. Referring now to FIG. 3, the wiring diagram or circuit of the-repeller shown in' FIG. 2 is schematically illustrated. The circuit includes a source of energy such -as a battery B, preferably of the type used in portable radios or the like, and having a voltage on the order of to 200 volts and preferably about volts. A re sistor R is connected in series with the battery B and allows the battery to charge a power capacitor C and invention-shown at the same time protects the battery from being shorted by the water or by a power transistor T connected in the circuit to send a pulse of direct current between a first pair of electrodes E and E A second power transistor T2 is connected in the circuit to send a pulse of direct current between a third electrode E and the first electrode E The power transistors T, and T are connected in circuit with a multivibrator circuit MV which alternately triggers the transistors T and T to alternately energize the pairs of electrodes E E and E E to alternately create 'two electromagnetic fields F, and F as seen in full lines and phantom lines, respectively, in FIG. 4, with the electromagnetic fields F and F disposed substantially at a right angle to one another. Each pair of electrodes E E and E E is energized approximately 35 times per minute to give a total of about 70 pulses of current per minute. The multivibrator circuit MV is conventional and will not be described in further detail.
Referring now more particularly to FIG. 4, the nature of the electromagneticfields F, and F created by the pairs of electrodes E E and E E is more clearly seen. Each field comprises lobes L and L2, respectively, generated in a direction perpendicular to a line drawn between the electrodes in each pair of electrodes. Electrode E, is common toboth fields, and electrodes E and E;, are alternately energized to alternately establish the fields IF, and F with the fields F and F disposed substantially'at a right angle to one another and accordingly, the lobes of each field extend across and cover the null zone NZ of the other field, In this manner,'electromagnetic radiation is'generated in all directions from a repeller and there is no area surrounding the swimmer which is not electromagnetically charged, thus eliminating the possibility of a shark or the like swimming up to the person through an area which is free of electromagnetic radiation. The circuit is automatically energized upon being submerged in water, with the water between the electrodes E E and E E serving as a switch means for automatically turning the repeller on when it is submerged.
Referring now to FIGS. 5, 6'and 7, a second form of the invention is illustrated and comprises a tubular housing 10 preferably made of a polyvinyl chloride material or the like and having a pair of electrodes 11 and 12 suitably connected at the opposite ends thereof. The electrodes 11 and 12 may comprise, for example, brass plugs threaded into the ends of the tube 10 and connected in circuit with a plurality of batteries B and a circuit board CB. According to one example, the tube I 10 is approximately three-fourths of an inch in diameter and is approximately 36 inches long.
Referring to FIG. 6, the circuit or wiring diagram of the repeller shown in FIG. 5 is schematically illustrated and comprises'a battery B connected in circuit with a resistor R, and power capacitor C The resistor R, enables the battery B to charge the capacitor C, but protects the battery from being shorted by the water or. by a power transistor T connected in circuit with the battery. The power transistor T is connected to an electrode E, to send a pulse of direct current between electrodes E, and E A resistor R is connected in circuit with the power'transistor T for dropping the battery voltage from approximately 135 volts to about 20 volts to operate a unijunction transistor T connected in a timing circuit or multivibrator circuit for periodically firing the transistor T The electromagnetic field F produced between the electrodes E and E is diagrammatically illustrated in FIG. 7 and comprises a plurality .of lobes L generated in a direction perpendicular to a line drawn between the electrodes E, and E A null zone NZ is created at the ends of the'electromagnetic field in which there is little or no electromagnetic radiation.
In use, the repeller 2 is attached to the back of a swimmer as seen in FIG. 1' or it may be attached to a life raft or boat or other object in a body of water, or it may be used in a fixed installation such as an electric field created at a fence surrounding a beach area for preventing elasmobranchii, such as rays or sharks or the like, from. entering the area of the beach occupied by bathers.
The repeller, according to both forms of the invention, is energized automatically upon being submerged in a body of water, and the pulsed transistors are such as to only partially discharge the power capacitor so as to conserve energy and thereby add tremendously to battery life, and ,yet the performance of a repeller is not reduced. The circuit in each of the two forms of the invention could use some means other than a transistor to cause the capacitor to be discharged, such as a silicon-controlled-rectifier orsemi-conductor or solidstate device.
In summation, a preferred form of the invention utilizes two .electromagnetic fields alternately energized ,and comprises a multivibrator' circuit which alternately pulses on two power transistors. The circuit is automatically energized upon being submerged in water, and each power transistor is pulsed on approximately 35 times per minute thereby producing pulses per minute in the water. The repeller could be used in a fixed In both modifications, the repeller is automatically energized upon submergence in a body of water and thus eliminates the necessity of a waterproof switch or the like and precludes the possibility of the person forgetting to turn the repeller either on or off.
As this invention may be embodied in several forms without departing from the spirit or essential characteristics thereof, the present embodiment is therefore illustrative and not restrictive, since the scope of the invention is defined by the appended claims rather than by the description preceding them, and all changes that fall within the metes and bounds of the claims or that form their functional as well as conjointly cooperative equivalents, are therefore intended to be embraced by those claims. r a
1. A repeller for repelling elasmobranchii with electrical energy, comprising at least three spaced apart electrodes connected in a circuit and submerged in a body of water, said water completing said circuit,
means connected in said circuit for periodically discharging a pulse ofi current through alternate pairs of said electrodes to alternately establish at least two electrical energy 'fields in a body of water when said electrodes are submerged in said body of water, said means including a battery .for supplyingenergy to said circuit,
said circuit and electrodes supported on a T-shaped housing, said electrodes secured in exposed position on the free endsof the housing and positioned relative to one another so that said electrical energy fields are alternately established along lines disposed at an angle to one another so that each electrical energy field covers the null zone associated with the other electrical energy field to create an electrical energy field surrounding said repeller and thus leaving no area free of electrical energy through which elasmobranchii are enabled to approach said repeller.
2. A repeller as in claim 1, wherein there are three electrodes in said circuit, a transistor connected in the circuit between each of two of the electrodes, and a capacitor, and a timing circuit connected with both of the transistors to alternately periodically discharge the capacitor through the transistors andthus the two electrodes connected with the transistors to alternately create two electric fields between one of the electrodes and first one and then the other of the remaining two electrodes.
3. A repeller as in claim 2, wherein the electrodes are arranged in a triangular pattern so that the electric 6 fields created by the electrodes are disposed at substantially a right angle to one another to eliminate the null zone associated with each of the. electric fields.
4. A repeller as in claim 3, wherein the timing circuit comprises a multivibrator circuit connected between the two transistors.
5. A repeller as in claim 4, wherein said electrodes I comprise brass plugs.
6. A device as in claim 1, wherein said circuit includes a capacitor, a source of energy connected with;
said capacitor, triggering means connected with saidcapacitor, and timing means connected with said triggering means to alternately periodically cause said ca- I pacitor to discharge a pulse of current across said pairs of electrodes.
, a 7. A device as in claim6, wherein said timing means comprises a multivibrator circuit.
8. A-device as in .claim 7, wherein said triggering.