Sept. 10, 1946. 2,407,329 Sept w, 1946. ‘ E. E. TURNER,‘ JR APPARATUS FOR SUBMARINE SIGNALING Filed July 22, 1939 ‘ 2‚4Ü7‚329 ‘ ’ 5 Sheets-Sheet 2 SepË. 1Û, 1946. E‚ E, TURNER‚.JR 2,407‚329 APPARATUS ‚ FOR SUBMARINE S IGNALING ‘Filed July 22, 1959 5 Sheets-Sheet 3 ‘ INVENTOR. Evww E.TURNEF2 dî2. BY ‘ Patented Sept. 10, 1946 2,407‚329 ’ äJNË'Ë‘ED S'Ê‘A’E'ES PATENT OFFICE 2‚407‚329 APPARATUS FOR SUBMARINE SIGNALING Edwin E. Turner, Jr.‚ West Roxbury, Mass.‚ as signor, by mesne assignments, to Submarine Sigma! Company, Boston, Mass., a corporation of Delaware Applicaticn July 22, 1939, Serial No. 285,910 2 Claims. (Cl. 177-386) 2 The present invention relates to translating striction oscillator for producing compressional devices ‘for converting compressional wave energy to electrioal energy and vice versa. More par vice along the line IV—IV in Fig. 3; Fig. 5 rep-‚ wave energy; Fig. 4 is a section of the same de resents diagrammatically a cross section of an electrodynamic oscillator; Fig. 6 is a cross sec tieularly, the present invention relates to such devices as used for signaling u-nder water and is particularly concerned with the transmission and reception of compressional wave energy in tion of the device of Fig. 5 taken along the line VI—VI; Figs. 7 and 8 are schematìc diagrams a beam. showi-ng arrangements Íor eiectrically connect ‚ ing the driving elements of the devices shown in It has heretofore generally been understood that if a vibratable piston be made large in its 10 Figs. 3 to 5; Fig. 9 is a vertical cross section of an electromagnetic oscillator simìlar to that shown dimensons in oomparison with the wave length in Fig. 5 but modi?ed in accordance with a modi of ‘the compressional waves at the signaling fre ?cation of the present invention; Fig. 19 is a quency, a concentration of energy along the axis vertical cross section of another modi?cation of perpendicular to the radiating surface will be such an electrodynamic oscillator; Fig 11 isa obtained. I-Iowever, such a concentration of schematic diagram of an arrangement fox‘ elec energy in a main beam is accompanied by smaller trically operating the devices of Figs. 3 to 5; Fig. concentrations of energy in directíons at various 12 is a vertica1 section of a further modi?cation angles with the axis of the main beam. of an electrodynamic oscillator; Fig. 13 is a hori When the relative acoustic energy intensities in space in the free medium as produced by such 20 zontal section of the device of Fig. 12 taken along the line XIII-XIII; Fig. 14 is a vertical a device are plctted with respect to the several section of a stil] further modi?cation of an elec angular directions from the aXis perpendicular trodynamic oscillator; and Fig. 15 is a horizontal to the radiating surface as om polar coordinate section of the device of Fig. 14 taken along the graph paper, the main concentration of energy line XV-—XV. will appear as a large lobe representing the main As shown in Fig. 1, the energy distribution ‘neem, and a plurality of auxiliary lobes or ears produced in a free medium by a representative representing the subsidíary energy concentra extended, continuous, ?nite, plane radiating sur-_ tions in directions other than that of the main face having a dimension greater than the wave beam will also appear. These auxilìary lobes length at the signaling‘ frequency vibratìng as of the energy distribution pattern are often ob a piston has a maximum energy concentration jectionable particularly Íor signaling under water along an axis y per’pendicular to the radiating as in acoustic ranging for the determination of surface. At small angles from the axis y the the dístance and direction of remote objects. energy decreases as indicated by the dotted line Such subsidiary energy concentrations can be re duced by not driving the plane radiating surfac'e 60. At some larger angle from the axis 1/ the as a piston but by driving it at varying amplitudes radiated energy will fal1 to zero and at a still over its surface. A suitable amplitude distribu greater angle agaìn build up to a lower but still tion for this purpose will be shown below, but signi?cant maximum va1ue; then again fall to the present invention is primarily concerned with zero as the angle is ‘further increased, and so on arrangements for obtaining any desired vibra 40 throughout the hemìsphere facing the radiating tional amplitude distribution of the radiating surface. piston. 'I‘hus, there will appear successîve lobes of energy concentration at varìous angular dis It should be noted that the characteristics re tances from the axis y as indicated in Fig. 1 by ferred to herein as applying to a compressional the lobes e1, e2 and es. If the piston be circular, wave producing device also apply when the same 45 it will be understood that these subsidiary lobes device is used for receiving such waves. are in the form of hollow cones, the graph in Fig. The invention will best be understood by the 1 indicating merely the energy distribution in following description taken with reference to the one plane. accompanying drawings in which Fig. 1 is a polar A more desirable energy distribution pattern diagram of representative compressìonal wave 50 can be obtained by effectively varying the ampli energy distributions; Fig. 2 is a graph showing tude over the radiating surface from the edges a suitable radiating surface amplitude distribu to the center so that the greatest amplitude will tion for the production of one of the energy dis occur at the center. If, for example, the vibra tributions shown in Fig. 1; Fig. 3 shows dia gramniatically a cross section of a magneto 55 tional amplitude be varîed as shown in Fig. 2,‘ 2,407,329 ‘3 the energy distribution represented by the solid curve in Fig. 1 can be obtained. In Fig. 2 the linear amplitude of the radiating surface is indicated by the ordinates which rep resent the ratio Ar/AO representing the ratio of the amplitude at any radial coordinate measured 4 Wound en or embedded in the outside surfaces of the concentric poles are alternating current windings 8 to which energy is supplied at the sig naling frequency. The rings 5 are proportioned to have a height such that together with their i’espective portions of the element 4, they will each form a half wave length vibrating system from the center of the radiating surface to the at the signaling frequency. The entire system amplitude at the center, so that the maximum amplitude is indicated as unity. Radial dis will, therefore, be set into vibration when the tances from the center of the radiating surface 10 coils 8 are energized and conversely will generate are indicated by the abscíssae which speci?cally an electromotive force in the coils 8 when the represent the ratio r/a, where 1‘ is the radial system is vibrated by compressional waves. An distance from the center at any poi-nt and a‚ is electrodynamic oscillato-r of this type is described the total radius of the radiating surface. The in greater detail in my copending application particular amplitude distribution curve shown in 15 Serial No. 24,078, ?led May 29, 1935. this ?g‘ure follows the equation: When all the coils of the magnetostriction oscillator shown in Figs. 3 and 4 or all the driving coils of the electrodynarnic oscillator shown in (1) Figs. 5 and 6 are excited with alternating current 20 of the same amplitude and phase, the respective The amplitude distribution shown in Fig. 2 pro radiating surfaces will vibrate with a uniform duces an energy distribution in the medium as amplitude over the entire surface and thereby shown by the solid curve in Fig. 1. The main will produce an energy distribution in the medium lobe E0 has somewhat greater width than the as indicated by the dotted curve in Fig. 1. Con main lobe en produced by uniform amplitude of 25 versely if all the coils are connected to actuate an the vibrating surface but the auxiliary lobes E1, indicating device in a uniform manner, the device E2 and E3 are very much reduced in intensity. as a receiver will have a sensitivity in the various T0 produce such a desired energy distribution directions as indicated by the same dotted curve or any other desired energy distrbution it is neces in Fig. 1. sary to cause the radiating surface to vibrate with 30 T0 produce a different energy or sensitivity varying amplitudes over its surface when energy distribution I vary the ampere-turns of alternat is being‘ transmitted and conversely to cause the ing current excitation of the coils associated with surface to produce electrical response which varies the driving elements over the area of the radiating in a similar marmer when receiving. Two ar» element, or I provide diiïerent loadings of the rangements for accomplishing this with devices driving elements, that is I vary the mass ratio of the type shown in Figs. 3 to 6 are shown in between the mass of the driving elements and Figs. 7 and 8. their respective associated proportions of mass of Figs. 3 and 4 show a magnetostriction oscillator the radiating element. having a radiating element ! adapted by its outcr The variation in ampere-turns can be accom— surface to contact a signaling medium. 'I'his is 40 plished in two ways, namely by varying the turns driven by a plurality of tubes or rods 2 of magneto in the several coils and exciting all of them with strictive material ?rmly ?xed to the element i the same current or by giving all the coils the at one end and free to vibrate at the other end. same number of turns but different current excita— These tubes may be arranged over the inner sur tion or by a, combination of varying number of face of the element I in any convenient manner turns and diiîerent current values. The two but preferably are fairly uniformly spaced and Íundamental arrangements are shown in Figs. they may be arranged in concentric circles as 7 and 8. shown in Fig. 4. Per clearness only a relatively In Fig. 7 the elements 9, 10, 11 and 12 indicate small number of tubes is shown although in respectively the alternating current coils 8 for practice it is not uncommon to use many hundredg ‘ the four rings of the electrodynamic oscillator DÍ tubes. Each of the tubes together with its pro oortion of the element I forms a half wave length of Figs. 5 and 6 or the four circular groups of coils vibrating system with the node preferably located slightly above the inner surface of the element l. Elach tube is surrounded by an electromagnetic :oil 3 to which electrical energy of the proper fre :1uency is supplied for magnetostrictively setting the tubes and thereby the radiating surface into 2 of the magnetostriction oscillator shown in Figs. 3 and 4 with the individual coils of each circular group connected together in series. The grouping of the coils need not necessarily be cir cular, for this depends entirely upon the ampli tude distribution and the beam ‘pattern which it is desired to obtain. With the magnetostrictíon oscillator the indi vibration or conversely for »generating electrical energy when the radiating surface and the tubes 60 vidual coils in each group are given the same a‘re vibrated by compressional wave energy. An number of turns but the coils for the different ascillator of this type is described in more detail groups are given different numbers of turns, the .n my copending application Serial No. 677,179, group at the center having the largest number ìled June 23, 1933. of turns. Similarly with the electrodynamic oscil Another form of oscillator is shown in Figs. 65 later the coil for the innermost ring is given the 3 and 6. An element 4 having a radiating sur greatest number of turns, the other coils being~ îace in contact with the signaling medium has a given successively smaller numbers of turns. In valurality of concentric rings 5 of electrically both cases the variation in the number of turns zonductive material mounted on its inner surface. from the center toward the edge of the device is î’our such rings are shown in the dravvings al 70 made to conform as nearly ‘as possible to‘ the desired amplitude distribution, for exarnple, in ìhough more may be used if desired. A magnetic ìeld is produced across each of the rings 5 by accordance with Equation 1 given above. The neans of an electromagnet E5 having a plurality elements 9, lil, H and I2 constituted as just cle )f concentric poles extending between the rings scribed are connected in series and then across a and excited by direct current polarizing coils E. suitable source of alternating current b’;; means 2,407,329 6 5 of the leads l3 and I4, condensers I5 and [6 inter posed when necessary to prevent direct current from passing into the alternating current line and sociated with a much larger mass than is the innermost ring. A11 the rings, however, are tuned to the same frequency and the length of the sev eral rings consequently varies. Therefore, the rnass ratio varies between the successive rings whereby uniform excîtation of the driving coils will produce a varying amplitude distribution of coils as the alternating current. Since the coils the radiating surface. Thus any desired ampli in the varicus groups have different number of tude distribution can be obtainecl simply by mak turns, the application of the direct current po tential across all the groups connected in series 10 ing the surface 32 of a different shape to con— form with the particular distribution desired. would n0t provide the same ampere-turns of po The mass ratio between the various driving larizing ?ux for all the magnetostrictive elements. elements of the radiating surface can also be var To provide for this, a potentiometer I 1 is con ied by the arrangement shown in Fig. 10. In nected across a source of direct potential and the for power factor correction. . In the magnetostriction oscillator direct polar izìng current is usually passed through the same this case the radiating element 3!l has its inner several groups of coils are provided with suc surface divided by narrow circular slots into a cessively larger direct potentials to make the po plurality of rings 3%, 37, 38 and 39, each driven larizing ampere-turns in each group the same. by one or more electrodynamic elements 5 which This is accomplished by means of the common may be the same as these shown in Fig. 5 and in lead [8 and the potentiomet-er sliding contacts l@‚ 20, 2! and 22. In each of these leads chokes 23 20 horizontal section would appear as in Fig. 6. The outermost portion 35 of the radiating member is are provided to avoid alternating current from made the thickest. The other elements 31, 35 passing through the potentiometer. For the sup— and 39 progressively decrease in thickness, the p1y of polarizing current in this manner, the thinnest element-being at thecenter. The mass switches 5ll must, of course, be closed. associated withthe several driving elements 5 is For the electrodynamic oscillator or for the therefore varied in a manner similar to that of magnetostriction oscillator in the case where sep arate polarizing coils ‘are provided‚ the polarizing coils may, of course, simply all be given the same number of turns and suitalc-le groups supplied in series or in parallel from a single direct current source whereby the polarizing flux in all the ele ments will be the same. Any desired variation of ampere-turns can also Fig. 9, whereby with uniform excitation of the rings the radiating surface will vibrate at vary ing amplitude, the greatest amplitude being at the center. In this case, also, it will be understood that magnetostrictive driving elements can be substituted for the electrodynamic elements shown. A further arrangement for obtaining a desi_red be obtained by the modi?cation shown in Fig. 8. amplitude distribution over the radiating surface In this case the elements 9, lil, H and !2 con by variation of the mass ratios of the several stituted as described with reference te Fig. 7 are driving elements is shown in Figs. 12 and 13. In all given the same number of turns. Alternating this case the electromagnetic driving rings, of potential of the proper Írequency is supplied to which four are shown, nuznbered 55, 56, 51 and the primary 2‘?! of a transformer 25 having a tapped secondary 25. The elements 9 to I2 are 40 58, are made of successively dìrninishing thick ness, the thickest ring loeing placed near the cen connected in series. one end of the combination ter. As in the other modi?catìons the rings are being connected to one terminal of the secondary all tuned to the same frequency having regard 26 and the junctions between the elements 9 to to the respective prop0rtions of mass of the radi I2 being connected to the several taps as by the ating element 59 which is associated with each. leads 21, 28, ‘2e and 3il. The taps on the sec Each ring, therefore, together With its proportion ondary 26 are adjusted so that the various ele of the element 59 forms a one-half wave length ments 9 to l2 will be supplied with voltages vary system at the signaling frequency. Since the ring ing in accordance vvith the desired amplitude dis tribution, for example, that according to Equa tion 1 above. Since all the elements 9 to [2 in this case have the same number of turns, they may be supplied with polarizing current from a single source of direct current through choke coils 3! by closing the swìtches 5í. The condensers 63 prevent direct current from passing through the transformer winding 26. Since the elements 9 to l2 are all connected in series, they will all receive the same polarizing ?ux. Another arrangement for preducing desired amplitude variations over the radiating surface consists in varying the mass ratios of the several driving elements. Fig. 9 shows electrodynamic driving elements but it will be understood that magnetostrictive elements may similarly be used at the center is thickel‘ than the other rings, the ratio of its mass with respect to the portion of the mass of element 59 associated with it is smaller than the corresponding mass ratio for the other rings. The central portion of the radiating ele ment 59 will therefore be driven at a greater am plitude, and the amplitude will gradually decrease toward the edges Îor successively decreasing ring thicknesses as shown. It will be evident from what has been said With reference to the other modi?cations that the variations in the thickness of the successive rings can be made to bring about any desired amplitude distribution over the radiating surface. It will also be evident that the same arrangement can be applied where mag netostrictive driving elements are employed. In if desired. The electrodynamic elements 5 are 65 this case the tubes or rode near the center of the diaphragm will be made thickest and succes‘ similar to those shown in Fig. 5 and in horizontal sively thinner elements will be used at points out section would appear as in Fig. 6. Likewise, the from the center to conform to any desired radi alternating current coils 8 and the polarizing coils ating surface amplitude distribution‚ '! are similar to these shown in Fig. 5. The al ternating current coils as well as the polarizing 70 A still further modi?cation Íor obtaining vary ing mass ratios is shown in Figs. 14 and 15. In coils are connectecl electrically to have uniform this modi?cation the driving rings 5 are again excitation and to produce uniform eleztrical re all of uniform thickness but are spaced differ sponse when vibrated. However, the inner sur ent distances apart so that the several rings are face 32 of the radiating element 33 is made dish shaped. By this means the outermost ring is as 75 associated with more or less of the mass‘and. 7 3 surface area of the radiatîng eiement‚ here num bered E9. Where a large amplitude at the center of the radiating surface is desired, the driving in Fig. 1. The auxiliary maxima will be seen to be of much 1ower intensity in this case and the largest one E1 lies in a direction different Írom elements are spaced most c1oseiy at the center that of any of the subsidiary maxima of the as shown. Since all the driving elements are dotted curve. Consequently energy transmitted supplied with the same power, those at the center in directions other than that. of the main bearn‚ being required to move the 1east radiating sur after re?ection from a distant object or f1‘om dis face area, wì1l drive the latter with the greatest continuities in the medium, will not be received with apprecíable intensity. amplitude. In this maner any desired ampli The arrangement shown in Fig. 11, therefore, tude distribution aan readily be obtained. Where 10 provides a means for changing from one energy magnetostrictive driving elements are employed, distribution pattern to a diiîerent energy dis— they, too, of course, will be spaced close together tribution pattern between sending and receiving. at these areas of the radiating member where the greatest amplitude is desired. It wi1l ‘ee evident that the arrangement shown When using apparatus of the type just de 15 is ‘net limited to the use of the particular energy d‘stributions shown in Fig. 1, but th‘at any other scribed for echo I‘anging purposes it may be ad vantageous for the purpose of reducing stray sig different distributions may be employed if desireei. It however, particulariy advantageous iîï the subsidiary maxima during reception do the initial impulse and to use a diiïerent energy 20 not cîoincide in direction with the subsidiary maxima obtained during transmission and also distribution pattern for receiVing the echo. This When the subsidiary maxima during reseption are is readily accomplished with the devices shown as small as possibie in intensity. This arrange in Figs. 3 and 5, particularly When al] the coi1s ment is aîso of especial importance When it is are given the same number of turns and the desired to receive as litt1e energy as possible from ampere-turns variation is obtained by varying directìons outside of the main beam and yet to the voltage applied to the several groups of coils. transmit as much energy as possibie into water Fig. 11 shows an e1ectric operating circuit for this during sending. Since a piston radiating surface purpose. Here the elements 9, lil, II and !2 has uniform amplitude all over its surface, its representing the coi1s associated With the several na1s and. reverberations to a minimum to use one energy distribution pattern for transmission of rings of an electrodynamic oscillator 01’ repre senting successive groups of series connected c0i1s of a magnetostriction oscillator are connected to’ cntire surface can be driven at the maximum pessible amplitude, namely that at which cavita tion cocurs, whereby ‘the greatest possible amount of energy wil]. be radiated along the main axis perpendîcuiar to ‘the radiating surface. When soms ot'ner amplitude distribution is employed, oniy the area oi maximum amplitude can be per energized from a battery or other current source mitted to reach the cavitation limit, while the re 42 through the upper contact 43 of a sending mainder of the surface must vibrate at a 1ower key 44. When the key is not depressed, contact amplitude. This results in a decreased tota1 en 43 will be closed and relay coil 4l energized where by re1ay contacts 54 wi1l a11 be closed. In this 40 ergy output, and at the same time decreases the maximum energy radiated along the main axis. condition which is for receiving the elements 9 to I?. are each connected to appropriate portions The use of the arrangement shown in Fig. 11, of the winding 26 to produce a resultant response i1owevcr, makes it possible to radiate maximum in the other winding 24 of the transformer in ac total, ene1‘gy during transmission and yet have cordance with any desired energy distribution g. 01 the bene?ts of a special distribution pattern dur— the tapped winding 26 of a transformer 25 through the contacts of a three-pole relay 40 having an operating coil 4I. The latter is arranged to be pattern preferably that de?ned by Equation 1. Íi1g reception. The winding 24 of the transformer 25 is at this time connected through the contacts 48, 52 of a double-pole, double-throw re1ay 47 to a receiving ampli?er 53 which may be connected to any de sired indicating device. When the key 44 is depressed for sending a Having now described my invention, I claim: 1. A submarine sígnaling device having a s’o1id unitary radiating member having a continuous radiating surface of surface dimensions many tiines the Wave iength of the compressional waves in the signaling medium at the signaling fre c;uency, said surface adapted to be in contact with signa], contact 43 is open, thereby deenergizing re1ay coi1 4! and permitting contact 54 to open. The eiements 9 to |2 are then connected in series and together across the entire winding 26 of transformer 25. Depressing the key 44 a1so the signaling medium, said radiating n‘ember having a reverse surî’ace opposed to 5 1d 1îrst Î ce with a plurality of metallic eiastic iongi— ‘ c1oses contact 45 energizing the re1ay 0011 46, "d thereon e radiating whereby contacts 43 move to the right as shown member, a plur„ ..„’‚; in the drawings and connect with contacts 49. 60 COÍÎS operatively assoc' The transformer winding 24 is thereby connected ments i‘o‘r vibrating t same, sa‘d eïeotric cur to a suitabie source of alternating potential of rentncarrjing coiis p-osuione-zi nearer the center the sìgnaling frequency. Since the elements 5! to 12 are now a11 connected in series, they wi11 be energized equally and, assuming that they have the same numbers of turns, the energy dis tribution pattern for the transmitted signal wì11 be that of a piston as is represented by the dot ted curve in Fig. 1. By this arrangement it will be noted that the transmîtted signal has a strong main beam to gether with subsidiary maxima at varìous angu 1ar directions to its axis. On receiving, however, the sensitivity distributíon if made in accordance with Equatìon 1 wi1l correspond to the solid curve 75 tî1e radiating member havìng greater ampere-turns magnitude than the‘ coiis oper atively associated with metallic elements nearer the perip’nery of the radiating’ member wherehy ‘the Î‘Îadiating areas naar ‘the center of the radiatirig mem‘cer are‘ excited with ‘large ampiitudes than ar progressively Írom ‘the een of ‘the ra„_ ting mem‘ner Îor the pur— oi red-ucing the intensity of the secondary 1obes of the beam pattern of the submarine sig« naiing device. 2. A submarine signaling device having a solid unitary radiating member having a continuous 9 10 radia‚ting surface of surfa‚ce dîmensions many times the wave length of the compressìonal waves in the sìgnaling medium at the sîgnaling fre quency, said surface adapted to be in contact with the signalíng medium, said radíatíng mem ated in groups wíth respect to theìr dista‚nce from the center of the ra‚dìating member, the groups of coî1s nearer the center of the radiating mem ber havî’ng a reverse surface opposed to saìd ?rst surface with a‚ pluralìty of magnetostrictive longi tudinally víbratable rode mounted thereon sub stantîally extendìng over the entìre radiating member, a pluralíty ‘of electrìc current-carrying c0í1s surrounding saîd tubes for operatively en ergizîng the same, saîd electríc current-carryîng coi1s having connections whereby they ‘are oper ber having greater ampere-turns magnîtude than the coil groups progressively away from the center whereby the radìatîng areas near the center of the radiatìng members a.re excìted with larger amplìtudes than areas progressívely a‚way from the center of the radíating member for the pur pose of reducing the Ìntensîty of the secondary lobes of the beam pattern of the submarine sig nalìng device. EDWIN E. TURNER, JR.