US1742832A - Electric sound-reproducing apparatus - Google Patents

Description

Jan. 7, 1930. A, A THOMAS 1,742,832

ELECTRIC SOUND REPRODUCING APPARATUS Original Filed Dec. 29, 1926' 2 Sheets-She et i INVENTOR Jan. 3336. A. A. THOMAS I 1,742,832

ELECTRIC SOUND REF PRODUCING APPARATUS 1 Original Filed Dec. 29, 192 2 Sheets-Sheet 2 Patented Jan! I930 v I I i lJNlTED STATES PATENT O AnoLrn A. THOMAS, or NEW YORK, 1v. Y. nnncrarc souma-aaraonucme APPARATUS Application filed December 29 1826, Serial No. 157,633. Renewed April 24, 1929.

My invention is-for an electric phonograph Fig.5 shows in transverse. cross-section a and other sound-reproducing apparatus of modified constructionof lid; novel construction, iii which a loudspeaking Fig. 6 represents diagrammatically a form diaphragm constitutes a structural part of of transmission system between the electric the lid or other closure of the cabinet or outer reproducerand the loudspeaking diaphragm, casing in whi'chthe operative mechanism is including a switch controlled by a rheostat mounted. When my invention is applied in arm for 0 ening the battery circuits; the construction of electricphonographs, no Fig. 7 shows in plan view a modified conhorn or amplifying chamber is required, and struction of phonograph having a-cylindrieal 10 the entire phonographic mechanism may be casing, portions of the constructlon being oused in a small case that is easily carried broken away to show certain parts; about. With proper transmission connec- Fig. 8 is a transverse cross-section on line tions between the electric reproducer and the 88 of Fig. 7; and loudspeaking diaphragm, it is possible to Fig. 9 is a diagram of another form of ave an inexpensive portable machine capa-- transmission system between the electric re-" 05 ble of full-toned reproduction comparing producer and the loudspeaking diaphragm.

- favorably with that of high-priced cabinet efore proceeding with a detailed descripphonographs. tion of the drawings, I want to explain that In a ,preferred form of my invention as I have purposely exaggerated the dimensions 20 applied to electric phonographs, I employ an of certain parts for the sake of clearness, so

electric reproducer of flat construction, lying that the illustrations are not to be considered horizontally close to the record and-thus conas shop drawings. tributing toward a cabinet of reduced height. Referring to Figs. 1 and 2, there is a box- Another feature of my invention is for a like cabinet or carrying case indicated as a volume-controlling device having means to whole by O, which in the present instance is cut out all circuits when the machine is not of rectangular shape and is adapted to be in use. I y easily carried about. In the broader aspect So that my invention may be fully underof my invention, any practical form or destood by those who are skilled in this art to sign of cabinet may be employed, but in cerenable them to practice the same, I have setain instances I prefer a cabinet consisting lected several illustrative embodiments for of a bottom section 10, a middle section 11, a detailed description. I want it understood, and a top section or lid 12. The sections 10 however, that the specific constructions shown and 11 are hinged together at 13, and lid 12 in the accompanying drawings are not to be is hinged to section 11 at 14. Suitable locks 35 regarded in'the nature of restrictions or limior latches 15 and 16 hold the sections of the tations, but rather as practical examples of cabinet in closed position when needed. If my invention. In these drawingsdesired, the cabinet1may be provided with a Fig. 1 shows in plan view anelectric phono-' suitable carrying handle (not shown). The graph of the portable or table type constructintermediate section 11 of the cabinet has a 40 ed in accordance with In invention, the lid motorboard 17, from which depends a motor of the case being thrown ack;

Fig. 2 isa transverse cross-section on line way. The motor 18 may be mechanical or 22 of Fig. 1, with the lid in closed position; electrical. In the present case I have assumed Fig. 3 is an enlarged plan view of the electhe motor to be mechanical, and so I have in- 45 tric reproducer shown in Figs. 1 and 2, the dicated a crank 20 for winding up the motor top plate being removed to show the parts springs. If the motor is'electrical, it ma 7 within; a v be driven from a battery housed within the Fig. 4 is a transverse cross-section on line cabinet, or it may be operated from the houseof Fig. 3, the top plate being shown atlighting circuit through suitable electric con- 50 tached; nections, which are well understood by those familiar with this art. As phonograph mosame and coil 39 in fixed position within the tors, both mechanical and electrical, are readreproducer casing. Two leaf springs 42 and ily obtained in the market in various sizes 43 are arranged in the casing to engage the and styles, I need not show or describe any extension 34 of needle arm N at opposite 5 structural details of motor 18. points, as indicated-at 44 and respectively. On motorboard 17 is mounted an arm 21 The upper spring 42 is secured to the cylinivoted at its rear end to swing horizontally drical wall of the casing at 46, and the lower over the turntable and also to have movement spring 43 is secured at 47 to the bottomplate in a vertical plan A simple way of mount- 27 of the casing. The contact oints 44, and m ing the arm 21 is by means of a hollow stand and 45 of the two springs are su stantially in 22 fixed on thejmotorboard and supporting a vertical alignment, so that the springs exert horizontally rotatable post 23 which has 9. equal and opposite pressures on the needle air (if trunnions 24. The arm 21 is provided arm to hold the same in normal predeterwith a transverse hub or bearing 25 adapted mined osition, as indicated in Fig. 4. The 15 to be supported between the trunnions 24-1501 to 1 dis 28 of casing 26' carries a pair of invertidal movement. The swivel 0st 23 persu ated binding posts 48 to which are conmits free horizontal movement 0 the arm 21- nected the leads 49 of coil 39. Similarly, the Any other practical form of mounting for bottom disk 27 has a pair of insulated bindthe arm 21 may be employed. The free end ing posts 50 for receiving the leads 51 of coil 2() of this arm carries an electric reproducer in- 37, The leads 51 being of very fine wire and g5 50 horizontal arm 34. The arm 33 is a hollow th i ht, amount dicated as a whole by It. This reproducer is readily flexible, do not interfere with the viof flat construction, so as to occup minimum bratory movements of the stylus lever.

space in a vertical direction and t ereby per- The operation of electric re roducer R will mit a reduction in the height of the cabinetbe clear from the preceding dbscription, and

as For this purpose, the reproducer R consists of may briefly, be described as follows, reference a flat casing 26 having a bottom plate 27 and bein had to Fig. 4. As the needle or stylus a top plate 28. The casing 26 is prefera l 35 v1 rates laterally in the record groove,the cylindrical 30f pill-box shape, I might sayi long arm 34 vibrates in a vertical plane and and is PIOVl ed witharadially extending hll coil 37 moves toward and away from fixed so 39 adapted to fit over the free end of supp r coil 39. Assuming that coil 39 is traversed by as ing arm 21. The lates 27 and 28 ma be sepaa primary current and that coil 37 is properly rate disks secure to the cylindrica body of connected in circuit in an amplifying transthe casing, or one of these parts may 08s mission system, it is clear that the movements integral with the casing structure.' Suitable of coil 37 with respect to fixed coil 39 will in- 35 means,such asa screw 30,- seeures the reproduce secondary current impulses in the circuit '100 ducer casing rigidly t0 the supporting a m, of coil 37 in accordance with the vibrations which is preferably a small light-tube (as of of the stylus point. The induced secondary aluminum, brass, etc.) adapte to conceal the impulses in coil 37 may be amplified in any connecting wires that run from the repropractical wayto operate a loudspeaking dia- 40 ducer to the transmission system below the phragm, as will later be ex lained more in t b d. The reproducer casing 26, detail. It will be observed rom Fig. 4 that which is best made of light non-magnetic Imthe vibrations of the stylus 35 are mechaniterial, is provided with a pair of lateral1y p r cally transmitted to coil 37 in amplified ratio, jecting ears 31, which carry sultable bearmg which in the present instance is about 1: 3.

45 members 32. These bearing members, whi h The coil 37 is very light and does not appremay be adjustable pointed screws, support a ciably increase the inertia of stylus lever N, stylus arm indicated as a whole by N. Thls which responds without hindrance to the sinarm is in the shape of a bellcrank lever comnations of the record groove. The springs 42 'prising a short vertical arm 33 and a long and 43 are so made and adjusted as to exert of mechanical impedance on cylindrical part adapted torecelve and supthe stylus arm. The absence of a magnet report a stylus 35, which may be a needle or any duces the weight of the reproducer, and there other practical member for engaging in is practically no magnetic drag on the stylus record groove. The horizontal arm 4: f arm, as in these prior constructions where an 55 stylus leverNextends into the casing through armature vibrates in a magnetic field. By 12 a slot 36. The free inner end of arm 34 cararranging the springs 42 and 43 so as to exries a small cylindrical cell 37, whlch 1S l'lgtend in opposite directions and yet have their idly attached in any practical way, as by contact points at the same distance from the means'of a small plate 38. On the top plate pivot of the stylus arm, I am able to use 28 of casing 26 is fixed a coil 39 in Substantmlspringsof considerable length in a small shal- "12 A ly axial alignment with coil 37. Qoil 39 is l e preferably rovided with a magnetic core 4 In Fig. 2, the reproducer R and supporting for intensi ying the magnetic effect of the arm 21 are indicated in playing position by coil. A screw 41, which may be of magnetlc dotted lines R and 21', a record 52 being 65 material, engages the core40 to secure the shown on turntable 19. In order to hold 4 inside face of the formed with radial arms 58, which termi-' the reproducer arm 21 in firm position when the machine is carried about, I provide a suitable support or rest, which may simply consist of a pair of spring fingers 53 mounted on the motorboa'rd and adapted to hold the tubular arm 21 clamped between them, as shown in Figs. 1 and 2.

The hinged lid 12' is provided with a circular opening 54 in which is fitted an annular frame 55. This frame has radially extending lugs 56 adapted to receive fastening screws 57 for securing the frame to the lid. The frame 55 is nate in a cylindrical support 59 adapted to receive an electromagnetic driving unit 60. A cross-shaped piece or spider 61 is secured b screws 62 to the arms 58 for rigidly hol the driving unit 60' against the circular shoulder 63 of support 59, as best shown in Fig. 2. Any other practical means may be used for securing the driving unit 60 in proper position on the supporting frame 55. A loudspeaking diaphragm D, most conveniently made in cone form, is mounted on the circular frame 55, so as to cover com letely the opening 54 in the lid. The diap ragm D is fixed in position by being clamped between the annular frame 55 anda ring 64, which forms part of a grille or open shield parts 55 and 64 together, with the diaphragm D rigidly clamped between. A link or rod 67 connects the apex of the diaphragm with the electromagnetic driving unit 60. As such units are well known in the art, it will not be necessary to show or describe any structural details thereof, and it is sutlicient to say that the link 67 represents any practical operative connection, whether me-' chanical or magnetic, between the driving unit and the diaphragm.

It will be clear from Fig. 2 that the cone diaphragm D constitutes the greater part of lid 12 and forms a portion of the outer wall of the phonograph cabinet. Putting this differently, it may be said that the top of lid 12 consists of a vibratory wall D, which functions as a loudspeaking diaphragm. 13y so mounting the cone diaphragm D that 1ts apex extends outwardly, the supporting frame 55 and the parts carried thereby are substantially flush with the inner face 68 of lid 12, except for the lugs 56 which need only be a small fraction of an inch in thickness. This construction permits the use of a carrying case or cabinet of comparatvely small height. The different parts carried bfy the supporting frame 55 are secured to the rame before the latter is attached to lid 12, there- 75 carrying case or cabinet C are mounted the electric devices that go to make up the system' for transmitting with or without amplifica'tion) the electric impulses produced by reproducer R to the driving unit 60. In Fig. 2.1 haye shown, by way of example, a

. battery 69 and an amplifying transformer 70, but it will be understood that such other parts are mounted in the chamber below the motorboard asare required for the particular transmitting and amplifying system selected by the designer. If the reproducer R is of the electromagnetic type, as above described, the feeble electric impulses produced by the reproducer R is connected in the circuit of battery 69. The primary coil 71 of transformer 70 is also connected in the battery circuit in series with reproducer R. It may be supposed that the microphone re roducer comprises a flat cylindrical casing mounted horizontally on its supporting arm Screws or rivets 66 secure the annular 11k e casing 26 of the electromagnetic reproducer R. Since the'phonograph of Figs. 1 and 2 may have either type of electric reproducer, reproducer R may be mounted on arm 21 in lace of reproducer R. The secondary coil 2 of transformer 70 is connected with driving unit 60. and amplifies the current impulses in primary coil 71 suf-' ficiently to cause the driving unit to operate hragm D with requisite elficiency. Am-

'ng transformers for this purpose are easily constructed or may be bought in the market.

The machine of Figs. 1 and 2 is best operated with the diaphragm lid open, but it may also be operated with the lid closed. In the latter event, the cabinet ought to have soundopenings above the motorboard, as indicated at 17, to prevent damping of thediaphragm and to allow the sound-waves produced by the bottom face of the dia hragm to issue freely into the outer air. may be covered with gauze or otherwise rentiered inconspicuous; or they may be formed in an ornamental grille comprising part of the outer cabinet structure.

.The volume of reproduction in the system of Fig. 6 is controlled by a rheostat 73 having a pivoted conducting arm 74 turned bya knob on the motorboard. Arm 74 carries a dia pli brush or contact member 76 for engaging the r reslstance element 73. One end of this reslstanceis connected to one side of the battery through a conductor 77. The arm 74 is connected by a conductor 78 to circuit lead 79.

he openings 17.

board and with a recess 89.

-When the rheostat arm is in I that lid 12' and all Between the points 80 and 81 of the battery circuit is connected a switch S consisting of a fix'ed contact 82 and a movable spring contact 83. A; conductor 84 leads from point 80 to 5 contact 82, and a conductor 85- connects the sIpring contact arm 83 with conductor 78. he spring arm 83 is mounted on a suitable insulating support 86, which may conveniently be secured to the underside of motor- 17. The normal set or tension pf s ring 83 is such that the switch is closed. he rheostat arm 74 carries at its free end a cam head or projection 87. The s ring contact 83 is formed with an incline offset 88 As long as the rheostat arm 74 engages the resistance 73, the switch contacts 82 and 83 remain closed and the battery current flows through the reproducer and the primary coil 71. It will be noticed go'that th'erheostat is shunted across the battery 69. Consequently, when the rheostat arm is in position 74,'the maximum amount of current is shunted-around the battery and the. volume of reproduction is weakest. position 7 4", the resistance of the shunt across the battery is a maximum and most of the current flows through primary coil 71, so that the reproduction is loudest. When the rheostat arm 74 is moved toward the off position, as

shown in Fig. 6, the cam-head 87 strikes the inclined portion 78 of contact arm 83 and moves it away from the fixed contact 82. As

r soon as the cam-head 87 enters the recess 89 of spring 'matically locked against further movement contact 83, the rheostat arm is autoin the same direction, and the contact 83 is thus held in open position. This breaks the circuit throng primary coil 71 and rheostat cessed portion 89 of spring contact 83 is such that the rheostat arm is easily moved out of the recess by a slight turning pressure of the fingers on knob 75.

In Fig. 5 the cone diaphragm D is mounted in the top of lid 12' by means of a frame 90 adapted to be inserted into the lid from the outside. For this purpose, the lid 12' is formed with an annular ledge or should er 91 for receivin the ring 92 of frame 90. The diaphragm is secured to ring 92 in the same way as in Figs. 1 and 2. I shall not therefore repeat that part of the preceding description. Frame 90 is formed with an annular flange 93 which fits into the opening 94 of lid 12'. From the base of the annular shoulder 94 project radial arms 95, which are the equivalent of the radial arms 58 in Figs. 1 and 2. The circular supporting frame 90 and "all its parts are secured to lid 12' by screws or bolts 96, orother suitable fastening devices. Otherwise, what has been said about frame of Figs. 1 and 2 is applicable to frame 90 of Fig. 5. It is to be supposed parts mounted thereon attached to the lid from the outside and rest against a 73, The shape of cam-head 87 and the re-- sound waves are reenforced by may be substituted for lid 12 in Fig. 2. The mam difference between the constructions in Fi 2 and 5 is that in Fig. 2 the frame 55 an the attached parts are secured to the inner face of the lid, w ile in Fig. 5 the frame 90 1s firmly seated on the annular ledge 91. Such parts as are common to Figs.v2 and 5 are indicated by the same reference numerals.

In the modification ofFigs. 7 and 8, the cabinet or carrying case C 1s of cylindrical shape. In this instance, the lid consists of a circular frame 97 having an extension 98 to provide a hinged connection 99 with the b y of the case. The extension 98 may be formed with a depending lug 100 adapted to shoulder 101 on the case when the lid is thrown o n in upright position, as indicated by dotte lines in Fig. 8. The circular frame 97 is provided with radial arms 102 adapted to support the driving unit 60, as explained in detail in connection with Figs. 1 and 2. The loudspeaking diaphragm D is mounted on frame 97 by means of a clamping ring 103, which is secured to frame 97 by screws 104 or otherwise. The clamping ring 103 carries a dome-shaped panel 105, which performs the double function of shielding the diaphragm D against injury and deflecting sound waves through openings 106 into the outer air. The member 105 may also be described as forming a recessed chamber 107, open-at its periphery to the outer air and housing the diaphragm D. The parts 103 and 105 are referably cast or molded as a single piece, eing connected only by short radial arms 108. The outer wall of dome 105 may be colored and ornamented to suit the taste of the designer. To permit easy lifting of the lid, the annular frame 97 is formed with a finger-piece 109. When the lid is in open upright position, the sound waves produced by the front face of the diaphragm are projected forwardly, and these the sound waves produced by the rear face of diaphragm D and projected into the outer air by the domeshape member 105. If the machine is to be operated with the lid closed, it is desirable to provide the upper portion of casing C with sound openings of ample area, as indicated by dotted lines 110. If the machine is to be used only in the home and is not intended to be transported like a piece of hand luggage, the outer casing wall above the motorboard may consist wholly or partly of ornamental grille work through which the sound waves pass easily "'to the outer air when the machine is operated with the lid in closed. position. In that event, the soun waves produced by the diaphragm will issue partly through the grille work of the easing and partly through the annular passage 106 at the circumference of member 105.

In the chamber 111 below the motorboard V Fig. 9 an ampllfying transmission system be-' the usual way through filament primary coil 121 of 17 are housed the various tute the transmission system between the reroducer and the driving unit. The rectan ar outline 112 is supposed to represent a 53y battery consisting 0 Su essary to feedthe required circuits in any particular transmission system that ma be selected. By way of example, I have s own in tween the electromagnetic reproducer R and the diaphragm D. The fixed primary coil -39 is connected in the circuit of battery 113, Which operated by the rheostat arm, as described in reference to Fig. 6., The secondary coil 37, which is mounted "on the reproducer arm, is connected at one end to the grid 115 of an amplifying vacuum tube V. The other end of coil 37' is connected to one side of -the filament 116 through a conductor 117. Thefilament 116 is fed by a battery 118 and controlled by a rheostat 119 in the usual way. In the circuit of the plate battery 120 is the primary coil 121 of transformer T, one end of this coil being connected to the plate electrode 122 of tube V. The plate circuit is completed in 116 and conductor 123. The secondary coil 124 of transformer T is connected to the driving unit 60.

The operation of the amplifying transmission system illustrated in Fig. 9, will be clear to those familiar with the radio art, and so I need only say that the electric impulses produced'in coil 37 by the vibratory movements of the stylus arm cause voltage variations in the grid 115. These voltage variations produce amplified transformer T, and these amplified impulses are transmitted by the secondary coil 124 to the driving unit 60; Fig. 9 has been drawn as simpleas possible, omitting condensers and might be found necessary or desirable to improve the clarity and volume of reproduction. The use of such devices is well'known to those who are familiar with audio amplifying systems employed in the radio art.

Although I have indicated only one audio amplifying tube in Fig. several stages of amplification maybe used. In Fig. 7, the dotted outline V represents the vacuum tube of Fig. 9, and it is supposed that this tube is properly supported in cham-" her 111. In Fig. 8 the transformer .T is rigidly mounted in chamber 111. The batteries 114, 118 and 120 of Fig. 9 are properly supported in casing C, and they may be represented diagrammatically as a whole by the rectangular outline 112. By placing the batteries 112 at the rear of case 0' opposite the carrying handle 125, the stability of the closed case is increased. when the same is set down on the base provided by the straight extensions 126 and 127 on the top and beti,-m,aaa

parts that constimgs in the motorbo ch cells as are nec-" I board to the may be shunted by a controlling rheo \stat 114 and a cut-out switch vention that I have a greater degree by using chair for playing,

current impulses in the inductances that 9, it isobvious that tom of the outer case. Access to the arts in chamber 111 may be had either throng openard or through doors in the outer wall of casingCf below the motor- J- I ard This will be understood without the need of additional illustration. The'wires 128 in Fig. 8 nections may be led from-below the motor-; ing with the o ening and closing of the lid. In the finished machine this wiring may be concealed.

It will be clear. from the foregoing "description of several embodiments of my in-.

phonograph in which all the mechanismnecessary for loud;reproduction is mountpd in a small cabinet or box that is easily carried about. By making the diaphragm a structural part of reduce the height of the cabinet considerably, and this advantage is I the flat reproducer which constitutes one of my invention. An electric phonograph contained in a small vportable-z'box, and yet capable of reproducing with.the great -vol-' ume and fine tonal quality of large cabinet indicate how the electrical 6011-.

driving unit 60 Without interfere 1 provided an electric 5' the hd, it is possible to realized to even 7 of the features machines fills the crying need of those who dwell in city apartment houses where the rooms are small and space is scarce. My new instrument may be placed on a table or and when not in use it is easily tucked away in a closet or otherwise disposed of in a small space, like a hat box or suitcase.- Portable mechanical phonographs are not capable of giving a loud clear reproduction, owing to the necessarily small amplifying chamber, and therefore my invention possesses a usefulness wanting in those prior machines. Furthermore, my new phonograph may be manufactured at a much lower cost than large cabinet machines ing substantially the same or no better re production. Of course, my invention is not limited to electric phonographs of the portable type, for the various features above described may be embodied in a lar e household cabinet, or the small case containin the phonograph mechanism may be mounte on, or form part of, a cabinet having compartments for holding records or used for other household purposes.

The cylindrical case C of Figs. 7 and 8 may be constructed in three parts like the Figs. 1 and 2. systems of Figs. 6

giv-'.

{my invention and not by wa or limitation.

' art without departing invention as defined in Althou gh I have shownand described certain specific constructions, I want it understood that I have done so merely to explain of restriction Changes an modifications will doubtless occur to those skilled in the from the scope of the the following claims: I I claim as my invention:

a '1. An electric phonograph comprising a cabinet, a frame hinged at the top of said cabinet, a loud s eaking diaphragm secured at its edge to said frame and forming therewith a lid for said cabinet, whereby said diaphragm is open to the outer air when said frame is in closed position on the cabinet, an electric reproducer, and operative connections between said reproducer and said diaphragm.

2. An electric phonograph comprising a cabinet having a hinged frame at the top provided with an opening, a loudspeaking diaphragm secured at its edge around said opening and covering the same, whereby said diaphragm forms an outer part of a lid for the cabinet, an electromagnetic drivin unit carried by said frame for operating sai diaphragm, an electric reproducer, and electric transmission connections between said. reproducer and said unit.

3. A portable electric phonograph comprising a carrying case having a hinged top lid formed by a loudspeaking diaphragm secured at its edge to a part of the lid structure, and electric repro ucing mechanism for operating said diaphragm, which is open to the outer air when the lid is closed.

i. In electric sound-reproducing apparatus, a cabinet havin a hinged lid formed in part by a cone diap ragm, the apex of said diaphragm projecting outwardly, said diahragm being open tothe outer air when the idisclosed.

5. An electric phonograph comprising a cabinet having a hinged lid, a loudspeaking diaphragm secured at its edge to a part of the lid structure and forming an outer wall of said lid so that said diaphragm is open to the outer air when the lid is closed, an electromagnetic unit carried by said lid for operating said diaphragm, and electric reproducin mechanism for operating said unit.

6. l n electric sound-reproducing apparatus, a cabinet having a lid formed in part by a cone diaphragm, and a substantially conical or dome-shaped disk carried, by said lid over said diaphra m to deflect sound waves, said disk also shielding said diaphragm.

7 .'Anelectric phonograph comprising a cabinet, a frame hinged .at the top of said cabinet and provided with an opening, a;

cone diaphragm mounted on said frame so as to close said opening,'the apex of said diaphragm projecting outwardly, said frame and diaphragm forming a lid for the cabinet, whereb said diaphragm is open to the outer air w en said lid is closed, an electromagnetic unit carried by said frame for operating said diaphragm, an electric reproduceroperatively supported in said cabinet, and means for transmitting the electric impulses of said reproducer to said driving unit, said diaphragm and driving unit permitting closure of the lid.

8. An electric phonograph comprising a cabinet having a hinged section provided with an opening, a frame securedvto said section and forming a rigid structural parfl thereof, a loudspeaking diaphragm mounted on said frame and coverin said opening, whereby said diaphragm forms an outer structural part of the cabinet, and is open to the outer air when said frame is in closed position on the cabinet, an electromagnetic unit carried by said frame for operating said diaphragm, and electric reproducing mechanism for operatin said unit.

9. An electric p onograph comprising a cabinet having a hinged section on top provided with an opening, a frame secured to saidsection, a cone diaphragm mounted on said frame and covering said opening, the apex of said diaphragm projecting outwardly, said hinged section and diaphragm forming a lid for the cabinet, whereby said diaphragm is open to the outer air when said lid is closed, an electromagnetic unit carried by said frame for operating said diaphragm, an electric re roducer operatively supported on the motor oard of the cabinet, and means for transmitting the playing action of said re producer to said driving unit, said frame and the parts carried thereb lying substantially above the lower edge of said hin ed section so that the lid may be closed wit out interference by said reproducer.

10. In an electric phonograph, an electric reproducer circuit including a battery, a rheostat shunted across said battery for controlling the volume of reproduction, said rheostat having a pivoted arm manually adjustable, a switch in said battery circuit, said switch including a spring contact arranged to be actuated by said arm into open position when the arm is turned into a certain position, said spring contact automatically moving into c1rcuit-closing position when said arm is turned to volume-controlling position, and

means whereby said spring contact when Q trically connected with said driving openmg, means for section o ned b theii ward swmgm' of said mid le s ection for'ea y access to said electric arts, a top or lid section hinged-to the middle section and carr driving unit therefor, and an electric reproducer mounted on-said turntable and elec-' unit through saidtransmission s stem. 12. An electric phonograp comprising a cabinet rovided on top with a hinged section having an annular opening, a frame having a ring fitted around the edge of said securing said ring to said section a cone diaphragm secured at its edge to said ring with the apex of the diaphragm pointing outwardl said section and dia hragm constituting a inged lid for the cabinet, a grille fitting over said diaphragm and having an annular flange secured to said ring, the edge ofsaid diaphragm being rigid- 1y clamped between saidringand flange,

v radial arms extending from said ring and movement from t stylus.

terminating at the center in a support, an

electromagneticunit mounted in said support for operating said diaphra said frame and all parts carried there y being from said secand electric retion as a unitary structure,

operating said reducing mechanism for riving unit. p

13. In an electric phonograph having an arm pivoted for horizontal swinging movement and also for vertical movement, an electric reproducer comprising a shallow casing fixed in horizontal position on the free end of said arm, a bellcrank lever pivoted to said casing so as to vibrate in a vertical plane, said lever consisting of a horizontal arm and a vertical arm, means provided on said vertical arm to support a stylus for lateral vibra-- tion, and electric reproducing means in said casing operatively connected to the free end of said horizontal arm, which receives vertical e lateral vibrations of the 14. In an electric phonograph having an arm pivotedfor horizontal swinging movement and also for vertical movement, an.

electric reproducer comprising a shallow casing fixed in horizontal position on the free end of said arm, a bellcrank lever pivoted to said casing so as to vibrate in a vertical plane, said lever consisting of a long' horizontal arm and a short vertical arm adapted to support a stylus for lateral vibration, whereby the stylus vibrations are transmitted as vertical movements to the free end of said horizontal arm in amplified ratio, and electric reproducing means in said casing operatively connected to the free end of said horizontal arm.

15. In an electric phonograph having an arm pivoted for horizontal swinging movement and also for vertical movement, an electric reproducer comprising a shallow cas- 'ng a loudspeaking diaphragm and an electromagnetic ing fixed in horizontal position on the free end of said arm, a pivot sup ort and a slot at the edge of said-casing, a ellcrank lever mounted on said support to vibrate in a vertical plane,said lever consistin of a horizontal arm extending through said slot into the casing and a vertical arm adapted to support a stylus, said arms being so proportioned that the stylus vibrations are transmitted to the inner end of said horizontal arm in amplified ratio, electric reproducin means in said casing operatively connecte to the inner end of said horizontal arm, and a pair of horizontally arranged spring blades in said casing for engaging said horizontal arm on top and be low, said spring blades opposing each other to hold said bell-crank in predetermined normal position.

16. An electric phonograph reproduced for lateral-cut records comprising a casing adapted to be mounted on a supporting arm, a bellcrank lever pivoted substantially at its apex to said casing so as to vibrate in a vertical plane, said lever comprising a vertical arm and a horizontal arm, means on said vertical arm to support a stylus for lateral vibration, whereby the stylus vibrations are transmitted to said horizontal arm as sub stantially vertical movements there-oi, and

electric reproducing means in said casing controlled bythe vertical movements of said horizontal arm.

17. In electric sound reproducing apparatus, a case or cabinet having an outer hinged wall formed in part by a loudspeaking diaphragm, which thus constitutes an outer structural part-of said case or cabinet, the edge of said diaphragm being rigidly connected to said hinged Wall, an electromagnetic unit carried by said hinged wall for actuating said diaphragm, and electric mechanism in said case for operating said unit.

18. An electric phonograph reproducer comprising a flat cylindrical casing adapted to be secured flatwise to a swinging support, a horizontal arm carried by said casing and pivoted to vibrate in a vertical plane, a needle holder pivotally mounted on said casing to vibrate laterally for playing lateralcut records, said needle holder being arranged at one side of the casing so as to be freely accessible, means for connecting said needle holder to said means in said flat casing operated by the movements of said arm, and resilient means for holding said arm in predetermined normal position. 1

19. An electric phonograph reproducer comprising a fiat cylindrical casing adapted to be fixed in substantially horizontal posi-- tion on the free end of a horizontally swinging support, a bellcra'nk lever pivoted substantially at its apex to said casing so as to vibrate in a vertical plane, said lever comprising a vertical arm and a horizontal arm,

arm, electromagnetic means on said verticalearm to sup it 'a stylus for lateral vibration, whereb t e styhis vibrations are transmitted to sai horizontal arm as vertical movements thereof, a pair of coils mounted, horizontally in said casing, means for prodiicing relative movement of said coils by the vibrations of said arm, and resilient means for normally holding saidcoils in predetermined normal position. 10 ADOLPH A. THOMAS.

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