Патент USA US2116522код для вставки
May 10,1938. w. KUNZE - 2,116,522 COMPRESSIQNAL WAVE SENDER ANb RECEIVER Filed Dec. 5, 1935 75:41 wry ATTORNEY. 2,116,522 Patented May 10, 1938 - UNITED STATES‘ _ PATENT OFFICE 2,110,522 7 comasssromr. WAVE SENDER AND nnonrvaa Willy Kunze, Bremen, Germany, assignor to Sub marine Signal OompanaBoston, Masa, a cor poration of Maine Application December 5. 1933, Serial No. 701,012 ‘ In Germany January'l, 1933 _ '1 Claims. _ (01. 177-386) The present invention relates to apparatus for the production and reception of compressional waves, especially high-frequency waves. It has particular application to the production and re 5 ception of high-frequency compressional waves constructing the vibratory body of the oscillator in such a manner that a di?erent amplitude is ‘obtained at the radiating member than the am plitude of the magnetostrictive member. > This may be accomplished by employing masses, of 5 different magnitudes at the opposite ends of in a liquid medium such as water. In the present invention use is made of the . the magnetostrictive elements. These masses are ~ magnetostrictive properties of certain metals and then connected by elastic members, namely the . i alloys. Magnetostrictive oscillators, as devices of 10 this type are conveniently called, have been made in the past but have not been of great value on account of their small energy output. This was "in part due to the losses which occur in this type of device. It has been proposed, in order to keep 15 "the losses-low, to build up the magnetostrictive vibratory body from sheet rings or laminations. A pile of such laminations is assembled with thin layers of insulating material between them and the whole pressed together so ‘that a unitary body - 20 of definite natural frequency results. These arrangements have the great disadvan tage that at the high frequencies for which such apparatus is mostly employed large frictional _ losses are set up within the body of laminations. 25 It appears that this was due to the fact that an whole or a portion of the magnetostrictive ele ments. In such a structure the ends of the mag- 10 netostrictive elements having the largest mass will vibrate with the smallmt amplitude. . It is a known principle that a’ radiating surface will radiate in' substantially a single direction only if its dimensions are large compared to the 16 wavelength of the energy being sent out or re ceivcd. This principle may be effectively em; ployed according to the present invention by mounting upon a radiating plate a multiplicity of magnetostrictive elements covering substantially 20 the whole surface of the plate. Alternatively a number of magnetostrictive vibratory bodies, each composed of a plurality of magnetostrictive ele ments disposed parallel to but out of contact with each other and rigidly joined together at one 25 absolutely rigid union of the individual laminae‘ or both ends, may be constructed. A plurality of such vibratory bodies may then be mounted upon could not be assured. , An object pf the present invention is to s'et a radiating plate of large dimensions compared _' forth a magnetostrictive vibratory body in which to the wave length. If desired two such radiat 30 there is no looseness between the individual mem ‘ ing plates may be employed, one at each end of 30 bers which may give rise to undesirable frictional the vibratory bodies. _A directive e?ect may also losses. ' ' This is accomplished according to the present invention by employing a multiplicity of mag 35 netostrictive members of equal length, for exam ple, Wires, thin rods, sheet strips, thin-walled tubes or the like. These may advantageously be mounted parallel to 'each other without metallic contact between them, their ends being rigidly 40 joined together in some manner so that a single' unitary longitudinally vibrating body results whose natural frequency can be made use of. The joining of the ends of the individual mag netostrictive members may be made. either by be obtained by mounting the radiating surface or surfaces of the magnetostrictive oscillator at the focus of a parabolic re?ector. The invention may be further understood by 35 reference to the accompanying drawing in which Fig. 1 indicates schematically the construction of a vibratory body according to the present in vention; Fig. 2 is a cross section through the magnetostrictive elements along the line II-—II 40 of Fig. 1; Fig. 3' shows a cross section similar to Fig. 2 but in which the magnetostrictive elements are in the form of sheet strips rather than rods or tubes; Fig. 4 is a section through a complete 45 means of insulating material or by means of one high-frequency sender or receiver; and Fig. 5 45 or two metallic end masses. When insulating _ shows an alternative construction of a high-fre quency sender or receiver and particularly one ‘ material is used for this purpose, it may be ap plied in a liquid state or by means of suitable ad hesive or the individual members may be pressed 50 under pressure into the insulating material. A particularly useful construction is obtained when the ends of the individual members are rigidly joined to metallic masses as, for example, by 55 soldering, brazing or welding. Another feature of the invention consists in which has two radiating surfaces. ' In the modi?cation shown in Fig. l a plurality of magnetostrictive elements in the form of wires, 50 rods or tubes l are arranged parallel to each other without metallic contact with each other. They are spaced from each other by means of two insulating discs 2 provided with suitable holes through which the magnetostrictive elements are 55 2,118,529 passed. The individual elements I can easily be made with exactly the same length so that each has, accordingly, the same tuning as all the others. At the ends of these magnetostrictive. Cl elements there are arranged two metallic masses’ 3 and 4 which are rigidly joined to the elements I by soldering, brazing or welding as indicated at 5 and 6. If desired the insulating discs 2 may be omitted and the end masses 3 and 4 may them _10 selves be provided with the proper holes or slits in which the magnetostrictive rods may be in serted so that in this manner all contact between the elements along their longitudinal dimension is avoided. - . An electromagnetic coil 1 is mounted in a suit able manner around the magnetostrictive ele ~ ments. When alternating current of the proper frequency corresponding to the frequency of the vibratory structure is passed through the coil 1, 20' the individual magnetostrictive elements and thereby the entire vibratory structure will be set into vibration. A greater effect can be ob tained by also providing the coil 1 with a direct current which produces an initial magnetization. 25 By the above construction a vibratory structure is‘ obtained which vibrates as a whole using a The mass 8 may be ?xed to the plate ill by means of screw threads 35. The other end mass ll transfers the vibratory energy to and from the surrounding medium, for example, water. A coil l2 surrounds the vibratory elements 3. A cylindrical casing i3 is provided surrounding the whole structure and closed at one end by the plate Ill to which it is secured by means of the ‘screws 26 and‘ made watertight by a gasket II. The outer surface of the radiating member II is 10 covered by a membrane I‘ which may be made of thin metal pressed against the member I I and the casing I! by means of the clamping ring l1 and the screws 31. It has also been found ad vantageous to ?x the membrane l8 rigidly to the 15' member II as by means of soldering, brazing or welding. The coil I2 is connected through'con ductors ll to a source of alternating and direct current when the oscillator is used for producing sound waves or with an ampli?er when used as 20 a receiver. When alternating current is passed through the coil | 2 the end mass II is set into energetic vibrations which are transferred to the water as compressional wave energy. On the other hand, if compressional-wave energy strikes 25 the membrane ‘l6 which forms a part of the mass de?nite natural frequency. On the other hand, ’ I I, the vibrations are transferred to the magneto on account of the rigid connection of the indi strictive elements I and produce an alternating vidual magnetostrictive elements with the end 30 masses and by the elimination of insulating ma terial between the individual elements, the losses are reduced to a minimum. ' Fig. 2 shows a cross section through the mag netostrictive elements shown in Fig. 1 and dem 35 onstrates the manner in which substantially the whole inner surface of the radiating member 4 ‘is provided with magnetostrictive elements. The spacing between the individual elements is made as small as possible consistent with convenient mechanical construction and yet large enough to insure complete electrical and mechanical insu lation between the individual elements. By using a multiplicity of magnetostrictive elements cover ing substantially the whole surface of the radiat ing mass 4, vibration of the latter as a whole is ‘assured and no bending or diaphragm action takes place. In order to reduce electrical losses in the end masses 3 and 4, these may be slotted or they may be made of a special material of high electrical resistance. ' Fig. 3 shows a cross section taken in a similar manner as that ofFig. 2 but of a somewhat dif ferent contruction. In this case the magneto strictive elements are in the form of sheet strips I’ which are arranged radially about the longi tudinal' axis of the vibratory structure. In a manner'similar to that shown in Fig. 2 two insu current in the coil i2 which may be ampli?ed and listened to by means of a telephone receiver, or "30 ii' the frequency is above the audible range, the alternating currents produced in the coil l2 may be made audible by a heterodyne ampli?er or other known means. ‘ It should be noted that it is important ‘to pro 35 vide as small a space as possible between the housing l3 and the piston end mass II in order to prevent any diaphragm action in the mem~ brane I 5 which is used only for the purpose of making the inside of the oscillator watertight. Instead of using the metallic membrane l5 other material may be used, or the membrane may be omitted entirely and the space between the casing l3 and the end mass ll may be ?lled with some material such as rubber which is impervious to the water. - In the modi?cation shown in Fig. 5 magneto strictive elements I! are provided with end» masses 2!! and 2! designed to vibrate as pistons. The vibratory structure so resulting is supported at a vibratory node by means of a plate 24 of insulating material. If the end members 20 and 2| are of equal mass, the node will be at the cen ter of the elements IS. The plate 24 is secured in a casing formed of two parts 22 and 23 clamped 55 together by means of the bolts 30 made water tight by means of rubber gaskets 3| and 22. The lating discs may be provided having radial slits piston radiating _members 20 and 2| project through which the magnetostrictive strips are through the casing 22 and 23 and have their ends passed whereby the spacing of the strips from .formed in the shape of a truncated cone. The each other is assured. Alternatively the strips space between the members 20 and 2| and the may ‘be mounted in radial slots cut in the end casing is made watertight by means of the rubber masses 3 and 4 to which they are rigidly joined by rings 33 and 34. ~ Excitation of the magnetostric soldering, brazing or welding or by means of a tive elements is provided by the coils 25 and 26. hardened insulating material or the like. The These may be connected in series and supplied arrangement of the magnetostrictive elements with alternating and direct current, or one coil need not, of course, as in Figs. 2 and 3, be in a may be used for the direct polarization current circular form, but they may be arranged in any while the other ‘coil is used for the alternating desired con?guration to suit the purpose for current. 70 which the oscillator is to be used. ‘A further feature of the device shown in Fig. 5 Fig. 4 shows a soundsender or receiver in which is the provision of means for completing the mag-" 70 a 'magnetostrictive vibratory body 8 composed netic circuit. This consists of a yoke 21 which of a multiplicity of magnetostrictive elements is completely surrounds the coils 25 and 28. The joined to an end mass 9 which is, in turn, ?xed to air gaps 29 and 30 between the yoke and the 76 a metal plate I0 of relatively very large mass. members 20 and 2| are made as small possible 8,118,588 in order to avoid any unnecessary reluctance in the ?ux path. To reduce losses the yoke 21 is preferably laminated. Magn’etostrictive oscillators constructed ac cording to the principles of the ‘present inven tion are particularly useful for signaling under water between vessels, particularly submarines,‘ by means of high-frequency compressional waves. These devices are particularly useful in systems 10 for distance measurement according to the echo method. In this instance it is ‘desirable-to choose the radiating surface of the oscillator so large that a directional effect is produced in a direc ' tion perpendicular to the radiating surface, that 15 is the dimensions of the radiating surface must be large compared to the wave length of the fre quency employed. In order to keep the diameter of the radiating surface within reasonable limits ' it is preferable to choose the natural frequency 20 of the oscillator in the vicinity of or above the 3 with reference to each other, means including in part said casing of‘ magnetic material and said rods and forming a completely closed magnetic circuit through said rods and casing wall and a coil surrounding said rods for energizing the same. 4. Apparatus for producing and receiving high frequency compressional waves in water compris ing a cylindrical casing, means providing'a' heavy mass at one end of said casing and closing the same, a plate, a plurality of magnetostriction rods 10 mounted in said plate and positioned normally thereof and substantially covering the whole plate, a mass mountedat the other end of said rods, means attaching said plate to the n'rass at the end of the casing, the rods running longi tudinally thereof and the second mass being posi tioned in the opening at the end of the casing, means providing a web contacting said second mass and closing the end of the casing and a coil surrounding said rods positioned within the 20 audible limit. The excitation of the oscillator may be provided by alternating current produced casing for energizing the same. by a motor-generator or a vacuum-tube oscillator frequency compressional waves in water compris > 5.v Apparatus for producing and receiving high and may be controlled by a key. ing a cylindrical casing having an opening at one It has also been found useful to employ an im- , end, an assembly of parallel magnetostrictive rods pulse excitation produced by unidirectional cur closely spaced together but free from each other, rent impulses from the discharge of a condenser a mass positioned at each end of they rods and or ‘by means of the damped vibrations of an os ‘means mounting the rods in said ‘masses, said cillatory circuit having a spark gap» rods covering substantially the entire surface of 30 Having now described my invention, I claim: ' said masses, a coil surrounding said rods and com 30 1. Apparatus for producing and receiving high pleting the magnetic circuit for the rods about frequency compressional waves in water compris the casing, means for attaching said assembly at ing a casing having an opening at one end, a mass one end of the casing and means covering the positioned in said opening and substantially ?ll ing the same, means supporting said mass in said position comprising a thin web supporting said mass, means clamping said web at the end of the casing, a great number of magnetostrictive rods substantially covering one surface of said mass, 40 a coil surrounding said rods and means support ing said coil within said casing. 2. Apparatus for producing and receiving high frequency compressional waves in water compris ing a casing having an opening, a mass of sub 45 stantially rigid material positioned in said open ing and ?lling the same, means freely supporting said mass in said opening to allow motion normal 6. Apparatus for producing and receiving'high frequency compressionaiwaves in water compris ing a cylindrical casing, an assembly of mag netostrictive rods arranged parallel but close to one another, a mass positioned at each end of the 40 rods inv which the rods are mounted, said rods covering substantially the entire surface of said mass, means for fixing the assembly at the back of the casing, a cover ?xed to the front end of the casing and contacting said second mass, said rods being arranged parallel to the axis of said 45 casing and a coil positioned within said casing - to the surface of the mass, a great number of surrounding said rods, ‘said casing and rods com- . magnetostrictive rods, means mounting said rods pleting the magnetic circuit about the coil. 7. Apparatus for producing» and receiving high frequency compressional waves in water compris 50 ing a cylindrical casing having an opening at one end, a mass substantially ?lling said opening and means providing a thin web for attaching said mass to said casing, a great number of parallel magnetostrictive rods embedded in said mass 55 normal to the external surface thereof, said rods being spaced free from one another but substan so in said mass at the inside of said casing, said rods substantially covering the entire surface of ‘the mass and a coil surrounding said rods f0 energizing the same. ' 3. Apparatus for producing and receiving high 55 frequency compressional waves in water compris ing a casing having an opening at one end, a mass substantially ?lling said opening, means freely supporting said mass for motion transverse to its external surface comprising a thin web 60 supporting said mass and means clamping said web at the end of said casing, a great number of magnetostrictive rods mounted at the end of the mass within the casing and covering substantially the entire surface of said massfinsulating means 65 other end thereof for acoustically transmitting the vibrations to the propagating medium. spacing said rods and securing them in position tially so close together that no morethan another rod of the same diameter could be inserted be tween any two rods, a coil surrounding the whole 60 group of rods and means completing the mag netic circuit for the magnetic ?eld produced by the coil including said rods and the outer casing. WILLY KUNZE.