US1344352A - Steering apparatus - Google Patents

Description

E. A, PARMELL AND T. MCLEAN.

STEERING APPARATUS.

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E. A. PARMELE AND T. McLEAN.

STEERING APPARATUS. APPLxcATloN man AuG.10.191a.

Patented June 22, 1920.

2 SHEETS-SHEET 2.

` tion of the sound, whereby yUNITED STATES PATENT OFFICE.

nnwAnD A. rAnunLE Aim 'rami iiroLnAN, or s'iA'rnN ISLAND, :mw ironic.

STEERING APPARATUS.

Specification o! Letters Patent. Ptented June 22, 1920.

Application ma August io, isis. serial in. 249,257,

`and TRUE McLnAN, citizens of the United States, and residents of' Staten Island borough of Richmond, and State of Newl JYork respectively, have invented certain new and useful Improvements in Steering Apparatus, of which the following is a specification.

The object of our invention is to provide means for steering water craft, such for example as torpedoes, through the medium of sounds proceeding from another mechanically driven craft, such as an enemy, which sounds will affect our improvements in such a manner as to cause the craft having our improvements automatically tobe steered at such enemy. f

One of the particular features of our invention is to utilize the same in a self-propelled torpedo in such a manner that sound waves passing through the water from an enemy craft, such as a submarine, will affect the sound responsive member or members of our improvements when one or both of them receive such sound waves whereby to cause the steering rudder of the to'lpedo to be operated to steer the latter at the enemy craft so as to cause contact of the torpedo with the latter for its destruction.

In carrying out our invention we rovide a self-propelled craft, such as a torpe o, with -a pair of sound responsive instruments, such 'as submarine microphones, preferably near in such direction, or if the sound is received in both of said sound responsive instruments equally, said rudder will be held in position to cause the torpedo to proceed in the directhe torpedo will be caused automatically to hit an enemy craft from which such sounds proceed. By the use of our improvements it'only will be necessary to launch the torpedo in the general direction whence the sound waves from the enemy craft proceed, and our automatically operating umechanism responsive to such sounds will cause the /torpedo to be steered at such enemy.

Means for carrying out our invention will b e lmore fully hereinafter described and then pointed out in the claims.

Reference is to be had to the accompanyingwdrawings forming part hereof, Awherein igure 1 is a plan view illustrating our improvements diagrammatically, and showing .conventionally in diagrammatic form a portion of a torpedo equipped with our improvements; Fig. 2 is a partly sectional plan view substantially on the line 2, 2, in Fig. 3, illustrating a translating device adapted to be contljolled by the operation of the sound responsive instruments or microphones for controlling other circuits .illustrated diagrammatically in Fig. l; Fig. 3 is a side view of Fig. 2; Fig. 4 'is a plan'view illustrating means for balancing or stabilizing the last named device; Fig. 5 is a detail sec- -tion substantially on the line 5, 5 in Fig. 4;

Fig.- 6 is a partly broken plan view il trating'rudder controlling devices in more mechanical form than in the diagram of Fig. 1 Fig. 7 is a side view of Fig. 4, artly in section on the line Y7 7, in Fig. 6; ig. 8 is a section onn the line 8, 8, in F ig. 6; Fig. 9 isan enlarged detail plan view of' part of Fig. 6; Fig. l0 is a.section on the line 10, 10, in Fig. 9; Fig. 11 is a detail section of a brush of .the rudder controlling devices of F 1g. Fig. 12 is a section on the line 12, 12, in Fig. 6, and Fig. 13 is a diagrammatic view illustrating means to increase or intensify the action of the microphones hereinafter referred to.

Similar numerals and xletters orreference` invention, and need not be further described.

The torpedo also may be equipped with a war-head and otheressential parts for its proper operation and explosion, infany desired manner, provision, however, to be made within the torpedo to receive` iour improved mechanism for controlling the steerin of ther torpedo at an object or target rom which sounds pass through the water. The

rudder 4 for steering the torpedo laterally may be vertically journaled in the torpedo in any well known manner to be operated as hereinafter described.

At 5, 6, are sound responsive instruments, such as micro hones, adapted to receive submarine soun s, and as such microphones in themselves form no art of our invention, but are utilized thereln, a detail description of such microphones will not be necessary, it being understood that the sound responsiveinstruments or microphones may be constructed in any approved manner, such as similar to the microphones now used on vessels to detect submarine sounds proceeding from other vessels. We have shown the sound responsive instruments 5, 6, as located adjacent to the head or bow of the torpedo and as communicating with sound receiving horns or tubes 7, 8, which instruments and horns may be located within the torpedo and the receiving ends of thel horns may open through the side of the torpedo, (Fig. l). An electric battery is indicated at 9 and one terminal thereof is connected by means of conductors 10, 11, with the corresponding terminals of the microphones. The other terminals of said microphones are shown connected by conductors 12, 13, with correspondin terminals of primary windings 14, 15, of induction coils or transformers a, b, the other terminals of which windings are shown connected together by conductor 16.

.The conductor 16 is connected to one terminal of the primary Winding 17 of a third induction coil or transformer c, the other terminal of which winding is connected to the terminal of batter 9 op osite the conductor 10. One terminall of t e secondary winding 18 of induction coil a is connected by conductor 19 with one terminal of coil 20 of a translating device d, from the other terminal of which coil a conductor 21, leads to the other terminal of coil 18. The device d may be o erated on the principle of a dynamometerrequenc meter. One terminal of the secondary Wlndin 22 of induction coil b is connected by con uctor 23 with one terminal of coil 24 of translatin device d from the other terminal of whic coil a conductor 25 leads to the opposite terminal of coil 22. The coils 2O and 24 may be of insulated wire wound side by side in the same direction or parallel andspaced a art upon an insulating hollow core 26 which may be secured in a suitable frame 27 (see Figs. 2 and 3). Within coils 20 and 24 and normally at right an les thereto, is a coil 28 of suitable insulate wire wound upon an iron core 29, which may comprise laminated sheets, the direction of winding 28 being normally substantially at right an les to the direction of windings 20 and 24. he terminals of winding 28 are connected by conductors 17, 17 with corresponding "terminals of secondary winding 17c of coil c, (Fig. 1). Windin 28 is pivotally supported within the win ings 20 and 24, so as to turn under the influence of current therein and in one or the other of the last named windings as well as by reason of the difference of current in said windings and to be at right angles thereto when both of said Windings are equall excited. Pivots 30 and 31 project from t e upper and lower parts of core 29, are insulated therefrom and pass freely throu h holes in core 26, which pivots are journale in suitable bearings 32, 33 carried by frame 27 (Figs. 2 and The rotary movements of coil 28 are intended to control circuits which in turn will control rudder 4. The amount of laminated iron in core 29 may be governed by the frequency of the sounds generated by the submarine enemy. )Ve have shown an insulated finger 34 secured to and projecting from pivot 30 and disposed between opposing spaced spring-acting contacts 35, 36, normally in engagement with a Contact 37 that is connected to one terminal of a battery 38 (Fig. 1). The opposite terminal of said battery is connected by branch conductor 39 to relays 40, 41, the other terminals of which relays are connected by conductors 42, 43 to contact s rin s 35, 36, res ectively (Figs. l, 2 and 3 he'circuit of t e relays is thus normally closed when winding 28 1s normal or atn right angles to windings 20 and 24, and whereby when winding 28 swings to one side or another the circuit of one or the other of said relays will be broken by operation` of finger 34 against contact 35 or 36. The armatures of said relays thus are normally out of en agement with contacts 44 and 45 respective y, which armatures are connected to the corresponding terminal of battery 46 by branch conductor 47. Contact 44 is connected by conductor 48 to one terminal of the windin of a solenoid 49 and contact 45 is connecte by conductor 50 to one terminal of the winding of a solenoid 51 the opposite terminals of which solenoi sare connected by a branch conductor 52 to the terminal of battery 46 opposite the terminal thereof connected with the armatures of said relays (Fig. 1). The arrangement is such that when winding 28 swings to one side or another and operates the corresponding spring contact 35 or 36, the circuit of` relay 40 or 41 will be broken, and its armature will make engagement with the correspond ing contact 44 or 45 whereb the corres ondin solenoid 49 or 51 will e energize n order to avoid undesired movement of winding 28 with respect to windings 20 and 24, due to rollin pitching or other movements of the cra t or torpedo, the frame 27 (Figs. 2 and 3) vmay be supported in a universal manner and preferably provided with a pendulating weight tending to maintain said frame in a lnormal position of equilibrium. An arrangement for such purpose is illustrated in Figs. 4 and 5, wherein said frame may be inclosed 'in a box 27L (or the frame may be in the form of a box), provided with pivots e, f, which are shown attached to a ring g, which pivots are supported by a surrounding ring k. The lring h is within a stationary rame or support shown in the form Vof a ring fi, and pivots j, It, connect ring h with ring or frame z at right angles to the pivots e, f. The ring or frame t' may have supports or uprights m, secured in suitable position within the toredo or craft. At n' is a we hted pendulum (Fig. 5) depending from rame 27 or its box 27a. The arrangement is such that the coils 20, 24 and 28 will remain balanced'in a normal position by reason of the ability of the rings g and h to assume diilerent positions and the balancing of the coils by the pendulum during various positions, the craft or torpedo may assume in the water, and whereby the coil 28 will be maintained in a proper position for operating with respect to coils 2() and 24 in manner before described.

Solenoids 49 and 51 (Fig. 1) are utilized as a means to cause operation of rudder 4 to one side or another from its normal position for steering the torpedo on a strai ht course. A suitable motor may be utilize for controlling the operation of the rudder throu h the medium of the action of said solenoi We have diagrammatically illustrated a reversible electric motor wherein 53 indicates the armature and 54 indicates the field winding of such motor, one terminal of which armature is connected to a battery 55 and the othei terminal of which armature is confnected by conductor 56 to contacts 57, 58

of a reversing switch. The other terminal of battery 55 is connected to contacts respectively controlled by switches 59, 60 and the terminals of field Ywinding 54 are connected to contacts controlled by said switches in an ordinary manner for control- ,ling reversing motors of the ycharacter speciied, the circuits through the switches being normally open. The switch 59 is controlled by a rod or the like 61 connected with core 49a of solenoid 49, and the switch 60 is connected by a rod or the like 62 with core 51 of solenoid 51. The arrangement is such that when core 49 is attracted the switch 59 will close the circuits of the motor through battery 55 to cause rotation of armature 53 in one direction, and when core 51EL is attracted the switch 60 will close the other corresponding circuits of the motor through battery 55 to cause rotation of armature 53 in a reverse direction. When neither solenoid core is attracted the armature will not rotate. To control the rudder 4 by the operation of the armature of such lation the contacts motor we have illustrated the followindg arrangements designed to cause the rud er to turn to one `side or another according to the sounds received in one or the other of the sound vresponsive instruments or microphones 5, 6, as well as to cause the rudder to steer the torpedo on a straight course in case the sound received in said instruments 5, 6 to which they are tuned, is equal, or in case no sound is received in said instruments. For such purpose we have illus-u trated a gyroscope having a contact that will maintain a substantially definite position regardless of the movement of other contacts coperative therewith due to deviation of the craft or torpedo from a straight course, or due to shifted positions of such contacts due to sounds received in the sound responsive-instruments or microphones 5, 6, for causing steering of the craft or torpedo in the direction from which such sounds proceed. The rotor of the gyroscope is indicated at 63 (Figs. 6, 7 and 8) and its supporting shaft 64 is shown pivotally supported in a ring 65 secured within a rin 66. Said parts of the gyroscope may be o any suitable or well known construction and any desired means may be provided to maintain rotation of rotor 63 during operation of our improvements. The ring 66 is pivotally supported within a frame 67 by means of pivots 68 shown connected with ring 66 and rotative in bearings in the ring 67. The base 67a of frame 67 may be suitably secured in the craft or torpedo in such a manner that pivots 68 will extend vertically, whereby the axis of shaft 64 of the rotor may remain in a previously set direction during rotation of the latter regardless of the deviation of the craft or torpedo from a straight course, or from the direction in which the torpedo may be launched. The rotor or one of its rings, such as the ring 65, is provided with a contact 69 (Figs. 1 and 6), which contact is connected to one terminal of a battery 70, as by a conductor 71 (Fig. 1). The opposite terminal of said battery is shown connected by branch conductor 72 with corresponding terminals of the windings of solenoids 73, 74, the other terminals of which windings are res ectivel connected with brushes 75, 76. aid brus es respectively engage movable contact strips 77, 7 8 which are insulated from each other. Said contacts are shown supported upon a rotative ring or member 79, (Figs. 6, 7 and 8), that surrounds the rotor rings 65, 66 and is free therefrom, insulation at 80 being carried by said ring to which insu- 77 and 78 are secured in any suitable manner, whereby they will be out of circuit with ring 79. Ring 79 may be supported for rotation around the gyroscope rings and rotor in any suitable manner. We have shown frame 67 provided with brackets or arms 81 branched on opposite sides of frame 67 and earrym ant1- friction balls or rollers 82 set in suita le recesses in said brackets or arms and receiving an annular groove 79 in the under surface of ring 79, whereby the latter is supported for rotation in an almost frictionless manner. Gears or rollers 83 are shown disposed around ring 79 and supported by pivots 84 carried by brackets or arms 81 to uide ring 79 during its annular movements.

aid ring is shown provided W1th peripheral teeth 85 coperating with sald gears. Disks 86 are shown disposed upon pivots 84 and ovverlie ring 79 to lieep the latter from rising from its bearings: A gear, such as a worm 87, is in mesh with teeth 85 for rotating ring 79, and the shaft 88 of said worm is rotated by armature 53 (F 1 g. 1), of the reversing motor, whereby said ring with its contacts 77, 78, may automatically adjusted in an annular direction with respect to contact 69 of the gyroscope rotor.

It will be noted in Fig. y6 that the opposing ends of contacts 77 and 78 are spaced apart, whereby the contact 69 may be 1n a position between said contact ends and the circuits (Fig. 1) from battery 70 through solenoids 73 and 74 will be broken. The cores 73, 74a of said solenoids are respectively operatively connected by suitable means, such as levers 89, 90., with rudder 4 (Fig. 1) whereby when said solenolds are not energized said rudder wlll be malntained in a direction fore and aft for steering the craft or torpedo on a straight course, whereas if only one of said solenoids be energized the rudder will be turned steer the craft or torpedo in a corresponding d1- rection. If the craft or torpedo deviates from a straight course a contact 77 or 78 will be caused to engage contact 69 which will be maintained in a given direction by the gyroscope, and thereupon one or the other of said solenoids will be energized to cause operation of the rudder 4 for returning the craft or torpedo to the straight course, whereupon engagement between contact 69 and one of said contacts 77 or 78 will be broken, as the contact 69 will once more rest on insulation.

Assuming that the sound from thecnemy craft, such as a submarine, is detected on a ship by the apparatus nor in use as comin, r from a given general direction, or assuming that such submarine or its periscope may be seen before the torpedo is launched, the gyroscope will be set or aimed by means of contact 69 for steering the torpedo in the direction of such sound or submarine in an ordinary manner, and the torpedo will be launched. If contact 69 is not in engagement with contact 77 or 78 (Fig. 6) the torpedo will proceed on this straight course.

If the torpedo is not proceeding in a course such as to cause it to strike an enemy craft or submarine, in the direction in which it has been launched, the sounds from such enemy submarine or other craft, received in one of the microphones 5 or 6, will cause How of current in primary winding 14 or 15 and in the primary winding 17. Assuming that the sound is received in microphone 5, the current flowing through windings 14 and 17 will cause flow of induced current in the secondary winding 18 and thence throu h winding 20, as well as through the secondary winding 17 of coil c and thence througlrwinding 28, whereupon the latter will be attracted to cause linger 34 to move to one side in Fig. 1 (depending upon the polarity of the coils to each other) breakin the circuit of relay 40. The circuit wil then close between the armature of said relay and contact 44, through battery 46 and solenoid 49, whereupon its core will be attracted and switch 59 will close the circuit of motor 53, 54 to cause rotation of armature 53 in such a manner that it will rotate worm 87 in the proper direction for rotation of ring 79 to cause circuit to be closed between contacts 69 and 77, whereupon solenoid will be energized and will cause turning of rudder 4, whereby the torpedo will be caused to turn in the direction of such sound. So long as microphone 5 receives the aforesaid sounds from the submarine or other enemy craft, the torpedo will continue to turn in the direction of such sounds until said sounds are received equally well in microphone 6, at which point the microphone circuits are balanced and coils 20 and 24 exert the same pull in each direction on coil 28 which remains stationary. When the sounds from an enemy craft are received in both microphones with substantially the same intensity the coil 28 returns to normal and the circuit of motor 53, 54 will be broken and rudder 4 will steer the torpedo dead ahead at the enemy and the torpedo will continue on such course so long as the sounds from the submarine are received equally in the microphones.

In case the sound from the submarine should have affected the sound-responsive instrument or microphone 6, instead of 5, the operations above described respecting microphone 5 would be reversed, that is to say, finger 34 would have been moved sidewise in Fig. 1 to cause breaking of the circuit of relay 41 and operation of the motor armature 53 in the reverse direction to cause contact 78 to engage contact 69, whereupon the solenoid 74 would be energized to cause the rudder to turn correspondingly to steer the torpedo in the direction of the sound until such sound equalizes in both microphones, or substantially so, to cause the rudder to steer the torpedo dead ahead. lt

will be understood .that'whenever the tor- ,p

o is steered at the enemy in sucha manjner that theA sounds pr g from the latter to both microphones 5, 6 substan- 6 tially aii'ect coils a, cnuall the currents -therein will become wi remain balanced, and the rudder will have returned toand will remain in normal position for steering ead ahead until Athe target -is 10 struck. It will be understood, furthermore, with the enemy submarine or target in mo tion the torpedo will follow the same, because the circuits through windings 20, 24 and 28 willvbe differently affected if the i1li soun'd is greater-in one microphone than another b reason'of such, movements of the enemy, w ereby the steering of the torpedo will correspond until both microphones again receive the sound equally and the tor- Y pedo will t j-proceed toward the enemy on aV straight co rse or dead ahead. Y

In case it should be desired to 'increase or' intensify the action of the microphones, receivers 91, such as telephone receivers; 2li' may be included in the circuits of the coils of the secondary windings 18 and 22 of the induction coils or transformers a and b, 13k the battery conductor 11 being conn to the ap ropriateterminals o sie said receivers, where y when current is in-` duced in windin 18 and 22 by the action of the microphone 5, 6 said receivers will act by their proximity to the microphones to increase the vibration of 85 their respective diaphragms to intensi the `current in the p windin o the i coils or transformers a, c. Sai receivers may be adjustably supported adjacent to the microphones so that the receivers may 40 be set in proper position with relation to tlie latter to produce the roper responsive tone and maximum amp cation, hence the desired effect.

To avoid d r of the torpedo following sounds other t an those emanating from `the enemy craft, it is deemed advisable to provide a correct amountv of iron. in core 29' or to tune the regenerative instruments 5, 91 and 6, 91 or both such iron and tuning, so that they will respond the more,

readily to the particular frequency of the enemy sounds.` By such m`eans in the tor. do it may not ,lib necessaryto stop the ship m which th torpedo is fired particu-i larl if the sound fr uency of the enemy cra is suilicientlyl di erent from that proceeding from such ship.

' Although in Fig. 1 the cores of the solenoids 73 and 74 areshown as y con oo nected with the rudder bg 'the interposed levers 89, 90, it will he rstood that said solenoids may be causedto operate valves for controlling well known compressed air means for operation of the rudder in a well manner. It will be understood `ma be varia le with respect to that the contacts 77 and 78 may he resistance contacts in casev the arrangement last described foroeration with com air is used for ntrolling the ru der operations, whereb the action of the solenoids 'I0 sai valves, and the brushes 75, .6 will be applied to such resistance contacts at the prpper positions.

e have referred to our improvements as 76 ladapted to control vertically pivoted rudder 4 for lateral steering of the craft or torpedo, but it will be understood that our invention may be utilized in connection with a horizontally pivoted rudder ada ted s0 to steer the craft or torpedo in vertica directions so as to seek an enemy submarineat v{'ililying depths ,in the water. v i

e We.- have illustrated and described an apparatus adapted to carry o ut the pur- 35 poses of our invention, it will be understood .that our invention is not limited to the particular devices set forth nor to the particular arrangement of the parts, instruments and circuits specified, as the same may be so varied, within the scope of the appended claims, without de arting from the spirit of our invention. A thong we have referred to our invention as being usefulfin a'torpedo of the class specified, it will be understood that th. same may be used in any other form of craft or vehicle capable of selfpropulsion and self-steering without the aid of human agency for such o rations.

Having now described our invention what we claim is: ,I c

1. A craft havingmeans for steering it and provided with sound responsive means, transformers having primary coils in circuit respectively with said sound responsive ies means, a translating device having coils respectively in circuit with the secondary coils of said transformers, a transformer havinlg1 its primary winding in circuit common wit the primary windings of the first named transformers and with said sound responsive means, said translating device having a movable coil in1 circuit with the secondary winding 0f the second named transformer, an'd electrically operating means interp between said steering means and said translatingedevice and operated by the movable mem r of the latter for controlling the operation of said steering means. a

2. A craft having means for steering it and provided with sound responsive means, transformers having primary coils in circuit respectively with said sound responsive means, a translating device having coils 'respectively in circuit with the secondary 125 coils of said transformers, a transformer having its rimai'y windin in circuit commonr with tlic primary win in of the first named transformers and wit said 'sound responsive means, said translating device havinfg a movable coil in circuit with the secon ary winding of the second named transformer, a motor to control said steering means, and electrically operating means interposed between said motor and said translating device and provided with circuits controllable by the movable member of the latter for controlling the operation of said motor.

3. A steering apparatus comprising a rudder, means to control operation of the rudder, sound responsive instruments, transformers havng their primary windings in circuit with said instruments, a translating device controlled through said transformers, relays having normally closed circuits controllable by said translatin device, a reversible motor for controlling the operation of the rudder controlling means, switch means to control the direction of rotation of the motor and solenoids having normally open circuits controlled by said relays for controlling the operation of the motor.

4. A steering apparatus comprising a rudder, means to control operation of the rudder comprising a reversible motor, solenoids having normally open circuits to control the circuits of the motor, relays having normally closed circuits to control the circuits of the solenoids a translating device havin a movable member to control the circuits o the relays, sound responsive instruments and electrically operating means operative by the sound responsive instruments for controlling said translating device.

steering apparatus comprising a rudder, means to control operation of the rudder comprising a reversible motor, solenoids to control the circuits of the motor, rela s to control the circuits of the solenoi s, a translating device having a movable member to control the circuits of the relays, soiind responsive instruments, transformers respectively havin their primary windings connected with said sound responsive instruments and an electric generator and having their secondary windings in circuit with corresponding coils of said translating device, and a transformer having its primary winding` in common with the first named primary windings 'and having its secondary winding in circuit with a movable winding of the translating device.

6. A plurality of sound responsive means, transformers having primary coils in circuit respectively with said sound responsive means, a translating device having coils respectively in circuit with the secondary coils of said transformers, a transformer havin its primary winding in circuit common witg the primary windings of the first named transformers and with said sound responsive means, said translating device having a movable coil in circuit with the secondary winding of the second named transformer, and mechanism controlled by said translating device.

steering apparatus comprising a rudder, a gyroscope having a contact, movable contacts to coperate therewith and out of contact with the first named contact when steering dead ahead, electrically operating means controllable through said movable contacts to control said rudder, electrically operating means to control said movable contacts because of engagement of one of the latter with the gyroscope contact when not steering dead ahead, and sound responsive instruments to control said second named electrically operating means.

8. A steering apparatus comprising a rudder, a gyroscope having a contact, movable contacts to coperate therewith and out of contact with the first named contact when steering dead ahead, solenoids operatively connected with said rudder, brushes connected with said solenoids and cooperative with the movable contacts respectively, electrically operating means to operate the movable contacts because of engagement of one of the latter with the gyroscope contact when not steering dead ahead, and sound responsive instruments to control said electrically operating means.

9. A steering apparatus comprising a rudder, a gyroscope having a contact, movable contacts to cooperate therewith and out of contact with the first named contact when steering dead ahead, a translatingdevice, electrically operating means controllable by said device to control said movable contacts, transformers having secondary windings connected with corresponding windings of said translating device, and sound responsive instruments having circuits con- Y nected with the primary windings of the transformers respectively.

10. A steering apparatus comprising a rudder, a gyroscope having a contact, movable contacts to coperate therewith and out of contact with the iii-st named contact when steering dead ahead, a translating device having stationary coils and a movable coil to control said movable contacts, transformers having their Secondary windings connected with said stationary coils respectively, another transformer having its secondary winding connected with said movable coil, and sound responsive instruments connected with the primary windings of the lirst named transformers respectively and in common with the primary Winding of the second named transformer.

11. A craft having means for steering it and provided with sound responsive means, transformers having primary coils in circuit respectively with said sound responsive means, a translating device having coils respectively in circuit with the secondary coils of said transformers, amplifiers includedin eruted by the movable member of the latter for controlling the operation o said steerin means.

bi ned at New York, county of New York 16 and l tate of New York, and Ithaca county of Tompkins und Stute of New York, respectively, this 1st dey of August2-19l8, and 6th day of August, 1918, respectlvely.

EDWARD A. PARMELE. TRUE MGLEAN.

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