US1765707A - Electric phonograph - Google Patents

Description

June 24, 1930. A. A. THOMAS I 1,765,707

ELECTRI C PHONOGRAPH Filed Feb. 1, 1927' 2 Sheets-Sheet l June 24-, 1930. THOMAS I ELECTRIC PHONOGRAPH Filed Feb. 1, 1927 2 Sheets-Sheet 2 INVENTOR Patented June 24, 193a water AnoLPH A. THOMAS, on new YORK, n. Y.

ELECTRIC rnonoenarn Application filed February 1, 1927. SerialINo. 165,052.

My invention relates to electric phonographs, and its object is to provide a hoinless instrument of novel construction and improved operation. As will appear later, my

invention finds special utility in electric phonographs of the portable type, producing a small instrument capable of great-volume and good quality of tone.

One of the main features of my invention is a loudspeaking unit consisting, in its preferred form, of two flat diaphragms adapted to accentuate diiferent bands of frequencies, so as to encompass practically the entire range of audible sound. These diaphragms are in the form of tensioned sheets mounted in close parallel relation on a flat frame, which is so pivoted as to be raised into upright position for operation of the diaphragms. When the lid of the machine is to be closedfthe diaphragm-supporting frame is lowered into horizontal position, where it occupies a shallow space adjacent the lid. In a preferred embodiment of my invention, the frame that carries the two diaphragms 5 is automatically raised and lowered by the opening and closing of the lid.

In the construction of a portable electric phonograph according to my invention, the carrying case is constructed of two shallow 3o box-like sections arrangedto provide two'- One compart- 4 compartments side-by-side. ment is for the phonographic mechanism (that is, the driving motor, turntable and electric reproducer), and the other compartment contains the double loudspeaker unit and all or some of the electric parts (namely, batteries, transformers, vacuum tubes, etc.) that comprise the amplifying transmission system employed. Some of these electric parts may be mounted in the phonograph compartment, if necessary or preferred. The arrangement of the two compartments sidebyside permits the use of a shallow case or box that is easily carried about and put out of the way. The carrying case may be made permanently fiat like'a mans suitcase, or the two compartments may be so hinged together I that onefolds over the other. In the latter modification, the case when closedhas a cubi- .6-6 of Fig. 5;

cal shape, but when open it is flat like the suitcase construction.

In order to explain my invention so that those who are skilled in the art may understand and use the same, I shall describe in detail the two embodiments shown in the accompanying drawings, in which-- Fig. 1 shows a cross-sectional front view of a portable electric'phonograph constructed in accordance with my invention, the lid of the carrying case being shown in closed position; i I

Fig. 2 is a transverse sectional view of Fig. l, with the lid and loudspeaker unit in raised position;

Fig. 3 shows a front view of the'machine with the lid open as in Fig. 2;

Fig. 4 is a fragmentary plan view showing a suitable mounting-for the electric reproducer on the motorboard;

F 1g. 5 is a perspective view of the closed carrying case in which all the parts of the machine are contained;

Fig. 6 shows a cross-sectional front view of a modified construction 'of portable electrio phonograph, in which the carrying case consists of two sections hinged together transversely;

Fig. 7 is a transverse sectional view on line Fig. '8 illustrates a cross-section through the carrying case when closed;

Fig. 9 illustrates, in reduced perspective, the carrying case of Figs. 57 in closed condition;

Fig. 10 shows in plan view .the doublediaphragm loudspeaking unit embodied in the machines of Figs. 1-8;:

Fig. 11 is a fragmentary detail to show a face view'of the magnet associated with the driving units of Fig. 10; and

Fig. 12 is a diagram of an amplifying sys tem for operatively connecting the electric reproducer with the driving units of the loud speaking mechanism.

Referring to the construction shown in Figs 1-4:, there is a carrying case K which has the general shape and appearance of a sultcase. The outer-structure of the case comprises a main section or body 10 and a lid 12 hinged at 13 to the rear edge of the main section. The shallow box-like section 10 is preferably provided with a' transverse partition 14 to increase the rigidity of the case. In that event, the lid 12 may have a transverse strip 15 arranged to rest on the top of partition 14 Whenthe lid is closed, as shown in Fig. 1. I

The transverse partition 14 divides the case into two compartments 16 and 17 arranged side-by-s1de. The righ'tcompartme'nt 16 contains the phonographic mechanism of the machine, and I shall therefore call it the phonograph compartment. In this compartment is a motorboard 18 carrying a driving motor 19, a turntable 20, and an electric reproducer 21. The motor 19 may be either electrical or mechanical. If the motor is mechanical, a winding crank 19f is adapted to be inserted into the right end of the case for winding the motor springs. If the motor is electrical, it may be operated b a battery in the carrying case, or by plugging into, an electric light socket. Since phonograph motors, both electrical and mechanical, are well known in the art and may be obtained in the market, it will not be necessary to show or describe any structural details of motor 19.

' The electric phonograph reproducer 21 is of any approved construction, either of the microphone or the electromagnetic type, and is so mounted as to move horizontally over a record. Since my invention is not limited to any particular form of electric reproducer, and since various constructions of electric reproducers are well known in the art, I need not encumber this description with the de tails of reproducer 21. It is suflicient to mention that the reproducer 21'is carried by an arm 22 pivoted at 23 for vertical and horizontal movement in the playing of a record.

v\Vhen. the reproducer is not inuse, the arm 22 is swung aside .and clamped in position 'by spring fingers 24 projecting upwardly from the motorboard, or by any other practical supporting means.

. The top space of the phonograph compartment 16 may be utilized to house a stack of records 25, which are secured tothe inside of lid 12 in any practical Way. In the drawings I have shown the records strung on a peg 26 to which they are secured bya wing-nut 27 and a clamping disk or washer 28. In Fig. 1

I have shown three 12-inch and three 10- inch records supported by the lid. The records do not interfere with the closing of the lid when. the reproducer arm .22 is held in rest position on support 24.

The compartment 17 which occupies the left half of the carrying case, contains my new loudspeakingmechanism and preferably also some or all of the electric parts that constitute an amplifying transmission system between the electric reproducer and the loudspeaking mechanism. A top board or cover plate 29 divides the compartment 17 into upper and lower chambers. In the lower chamber are mounted one or morg batteries 30, one or more audio-frequency transformers 31, one or more amplifying vacuum tubes 32, and other parts, such as condensers, rheostats, Potentiometers, etc., that may be necessary to complete any desired form of trans mission system. The cover 29 is hinged at 33 and rests on strips 3 1 secured in compartment 17. A suitable latch 35 engages the front edge of cover 29 to hold the same locked in closed position, and a linger piece 36 makes it easy to lift the cover for access to the electrical parts beneath.

M new loudspeaking mechanism is indicate as a whole by L and in its preferred form is constructed as follows, special reference being had tothe enlarged view of Fig. 10. A pair of loudspea- king diaphragms 37 and 38 are stretched on opposite sides of a flat rectangular frame F, which in the n'esent instance consists of a board or panel 39 carrying a pair of tubular side pieces 4-0. These side pieces may conveniently be formed from sheet metal and secured to the board 39 by suitable fastening devices 41, which may be screws, bolts, rivets, or the like. If desired, the fianged end portions of the side pieces 40 maybe secured together at 41 to increase their rigidity. The diaphragmstW and 38 "are secured to the side pieces 40 by resilient clamping strips 42 which are attached to the side pieces by screws 43 or otherwise. The clamping strips 42- are preferably formed with roughened engaging surfaces 42 adapted to grip the ends of the diaphragm against all possibility of slipping. Any other practical means may be employed for securing the diaphragms 37 and 38 to the frame F. The diaphragms 37 and 38 are made of elastic sheet material and are corrugated so as to be held under constant tension of the requireddegree. In other words, the diaphragms are stretched across the frame F with such taut ness that they vibrate properly with substantially equal amplitude over their acoustic surfaces. This free vibration of the diaphragms is due to the fact that they are attached at two edges only, leaving the opposite edges 44 and 45 free or floating.

In the broad aspect of my-invention, the two diaphragms 37 and 38 may be duplicates of each other and have substantially the same natural frequency. However, at the present time I prefer to construct the diaphragms so as to accentuate different bands of frequencies. That is to say, one diaphragm is adapted to operate most efficientsteel, iron, duralumin (an aluminum alloy),

copper, bronze, celluloid, paper, wood, parchment, and others along the same line. The diaphragm 37', for. example, may be of elastic sheet metal having a high natural frequency and capable of correctly reproducing the higher notes of the piccolo and violin, and the diaphragm 38 may consist of a non-metallic sheet having a low natural frequency'and capable of reproducing the deepest organ tones. The acoustic areaof the diaphragms is such that the resultant reproduction has a volume equal to' (and in someinstances greater than) that given out by large cabinet phonographs of prior construction.

The loudspeaking diaphragms 37 and 38 are operated by electromagnetic driving units mounted'on opposite'sides of the board 39. These driving units. which are indicated as awhole by M and M in Fig. 10, may be of any practical construction. By way of example and not as a limitation, I have shown a driving unit consisting of a permanent magnet 46 having a coil or coils 47 mounted on pole pieces 48. As shown in Fig. 10, the magnets 46 of the driving units are mounted in alignment on opposite sides of the board 39. so that the same set of screws or bolts 49 hold both magnets in position. The diaphragm 37 is provided with an armature 50 adjacent the polar ends of the associated magnet. Similarly, the other diaphragm 38 has an armature 51 inoperative relation to the pole pieces of its driving unit. If the diaphragms 37 and 38 are of Image netic-material, no separate armatures are necessary. Instead of having a magnetic connection between the 'diaphragms and their driving unit, the construction of the latter may be such as to require a mechanical connection between the diaphragms and the vibratory armature'of the unit. Such driving units are well known in the art and need not be illustrated. It will therefore be understood that the driving units M and M shown in the drawings are to be regarded as broadly representing any practical form of mechanism forop'erating the dlaphra-gms in accordance with current impulses generated by the electric reproducer of the machine. For convenience, I shallcall the windings 47 of unit M as the controlling coil of diaphragm 37, and the windings 52 of unit M will be referred to as the controlling coil of diaphragm 38.

"The board 39 of the loudspeaking mechanism is preferably solid so as to separate the diaphragms 37 and 38 acoustically. These diaphragms form a pair of shallow sound chambers 53 and 54, which are freely open to the outer air at the top and bottom. During the operation of the diaphragms, the air columns in sound chamber '53 and 54 are set in vibration, whereby the sound produced by the diaphragms is augmented in volume. Since the sound chambers 53 and 54 are separated by the board or panel 39, there is no interference between the vibrations produced behind the diaphragms. The board 39, which is substantially free of vibration, may be of light rigid metal, such as aluminum or aluminum alloy, or it may be of nonmetallic material, such as wood, hard rubber, bakclite and similar materials adapted for this purpose.

The unitary loudspeaking mechanism 11 is hinged at 55 to a, strip oG-fastened along the rear edge of compartment 17, as shown in Fig. 2. The board 39 is connected at its upper end to the lid 12 by a chain or strong cord 57. One end of this chain is attached at 58 to board 39, and the other end of the chain is connected to a flat helical spring 59 seoured to the inside of cover 12. The hinge 55 is formed with a bracket 60, which acts as a stop for the board 39 when the same is in upright position, as illustrated in Fig. 2. The spring 59 renders the connection 57 sufficiently elastic to prevent any undue strain at hinge 55. The lid 12 is held in open position by one or more collapsible braces (31 of usual construction. These braces, which act like toggles, hold the lid prop )ed open in such position that the loudspealting mechanism L is automatically maintained in up right position when the lid is open. As seen in Fig- 2, the open lid deflects forwardly the .sound waves that strike it from the rear dia- .57- and brace 60 to hold the loudspeaking mechanism in upright position, I may use a rigid collapsible brace like 61, or any other practical arrangement. Upon closing the lid, the mechanism L is automatically lowered into horizontal position, as shown in Fig. 1. When these parts are in closed position, the free edge of board 39 rests on a ledge 62 provided near the top of chamber 17. The lid 12 has a strip 63 arranged to engage the front edge of board 39 when the parts are in closed position. in Fig. 2, where it will be seen that the loudspeaking mechanism, is held against movement bymeans of the strips 62 and 63 lying on opposite sides of the board 39. The case may therefore be transported without any danger of injury to the loudspeaking mech This is indicated in dotted lines than one inch, and may even be less in small 'machines. We thus have a double diaphragm loudspeaker capable of giving tremendous volume andyet one that can be accommodated in a carrying case of small'dimensions. In the broad view of my invention, the loudspeaking mechanism need not be attached to the lid 12 for automatic raising and lowering by the movements of the lid. This mech-' anism may be mounted in any other practical way so as to lie normally within the casing and to be raised into-operative position.

In the modified construction of Figs. 69,'

the carrying case K consists of two box-like sections and 66 hinged together at 67 and forming when open two shallow compartments side-by-side. The section 66 contains the honographic mechanism indicated as a who e by and which may be the same as the mechanism in compartment 16 of Fig. 1. The section 65 contains the loudspeaker mechanism L and the electric parts that constitute the amplifying transmission system between the electric reproducer and the loudspeaking diaphragms. In the drawings I have shown a pair of vacuum tubes 68 and an amplifying transformer 69 mounted horizontally in chamber 70 of section 65. It will be understood that the parts 68 and 69 do not form the complete transmission system, but are merely indicated by way of example to show how such parts are housed in the carrying case. The chamber 7Q is closed by a cover plate 71 hinged at 72. What has been said about cover 'plate 29 in Figs. 1 and Qapplies fully to cover plate 71 without the need of repetition. v

The loudspeaking mechanism L Figs. 6-9 is hinged at 73 to a strip 74 in section 65.

.A strip 75 forms a stop for the mechanism L.

when the same is raised in vertical position, as will be understood from Fig. 7 To hold the mechanism in upright position, the board 39 is provided near its lower 'endwith a latchbar 76 pivoted at 77 and rovided with a forwardly projecting lug 8. On' one of the strips'79 that support the cover plate 71 is mounted a locking finger 80. After the mechanism L has been swung into upright position, the latch-bar 76 is turned down until the lug 78 engages the spring finger 80, as shown in Fig. 6, whereby the loudspeaking unit is securely locked in upright position.

A finger piece 81 near the free edge of board 39 permits the latter to be readily grasped by the hand for manipulation. When the mechanism L lies flat in the case-section 65,. the

front edge of board 39 rests on a strip 82.

A latch 83 locks the board- 39 in lowered position, so that the box sections 65 and 66 can injury to the loudspeaking mechanism. This will be clear by looking at Fig. 8.

In order to accommodate a stack of records in the carrying case K, I provide the phonograph section 66 with strips 84'along the top. I have already said that the loudspeaker section 65 has a strip 75 which forms a stop for the board 39. The stri 75 runs around the section 65 about hal Ava between the cover plate 71 and'the top e ge of the section. lVhen the two sections 65 and 66 are closed, as shown in Fig. 8, the strips 75 and 83 provide a space for receiving a tray or shallow box 85 adapted to contain a held in position by and between the strips or flanges 75 and 83. The case Kis easily carried about by providing each section 65 and 66 with a handle 87. Suitable lopks 88 hold the closed sections locked. g

The carrying case K, when closed, is cubical in shape and in that respect it differs from the carrying case K-of Fig. 5. When the sections 65 and 66, however, are in open posi-' tion, as shown in Fig. 6, the machine is flat like that in Figs. 1-3. In either construction we have a carrying case of comparatively small dimensions. To give an idea of the compactness of my new machine, I may mention that the carrying case in Figs. 1-5 is deep and about five inches high. The Cubieal case of 69 is about thirteen inches long, thirteen inches deep and eight or nine ineheshigh. The diaphragms of the loudspeaking mechanism L in the embodiments illustrated are about ten inches high and eleven inches wide. These figures, of course, are given merely by way of illustration and are not intended to operate as limitations of the invention. The size, shape and style of the carrying case may be so selected by the builder as to suit his particular taste, or what he thinks the public would like best.

Any practical system may be adopted for amplifying and transmitting the electric impulses of the reproducer tothe operating or controlling coils-of the diaphragms. A n ex-' illustrated in j Fig. 12 The operating coils 47 and 52ofthe loudspeaking mechanism are connected in parallel to the secondary windin 89 of an audio-frequency transformer T. In the c'ircuit of coil 47 is a variable inductance'90, and in the'circuit of coil 52 is a variable inductance 91. These inductances are so adjusted in value as to cause the diaphragms 37 and- 38 to give the best acoustic results. It has been previously assumed that diaphragm 37 operates most efiiciently on high notes, and diaphragm 38 is best on low notes. In that case the inductance value of the circuit of coil 52, which operates the low diaphragm 38, should preferably be greater than the induc tance value of the circuit of coil 47 which opcrates the high diaphragm 37 The relative inductancevalues of the circuits of loudspeaker coils 47 and 52 are adjusted by means of the variable inductance windings 90 and 91, as will be clear. to thosewlio are familiar with this branch of electrical engineeriiig. The primary coil 92 oftransfornier T is connected in the plate circuit of an amplifying tube V, which is of usual construction, having a filament 93, agrid 94 and a plate electrode 95. The'plate battery 96 is connected in circuit in the usual way, and the filament 93 is fed by a battery 97. Between the electric reproducer 21 and the grid 94 of the vacuum tube is interposed a'transformer T having a primary winding 98 and a secondary winding 99. One end of the secondary winding 99 isconnected to the grid 94 and the other end is connected to a conductor 100, which is connected-to one side of the fila- 25 meiit 93. The primary winding 98 is in the circuit of reproducer coil 101, in which thestylus vibrations induce electric impulses.

Itwill be understood from the preced ng description of Fig. 12 that the electric impulses in reproducer coil 101 are transmitted in greatly amplified form to'the secondary winding 89 of transformer T, and these -amplified impulses pass through coils 47 and 52 for. operating the loudspeaking diae. I pliragms 37 and 38. Although I have shown I 5 In a portable self-contained machine, all

the parts of the amplifying system used are mountedin the case, but in the broad aspect of my invention as embodied in a semi-portable or larger household cabinet, the amplifying system connecting the reproducer to the driving unit of the loudspeaker may be partly contained within the case or cabinet and partly outside thereof. Some amplifyi'ngsystems might be tooheavy for installation in portable 55 plionographs, and it might therefore be more convenient to use a separate amplifier, especially if the machine is in a home that has a radio set. The chambers 17 and 70 may be used for housing any suitable loudspeaking mechanism, with or without parts of an amplifying system, depending on the design and dimensions of the case.-

' Although I have shown and described cer tain constructions, I want it understood that my invention is not limited to the details set forth. The specific structures illustrated in the drawings are to be regarded merely as practical examples of my invention, which may be embodied in other Ways thanhereiu described. The case or cabinet containing the parts that constitute the complete phonograph need not be of the portable type, but may be constructed as a piece of household furniture. Ihave shown portablecases merely to emphasize the fact that my invention finds spe cial utility in portable electric phonograplis, which are particularly desirable by people living in city apartment houses where the rooms are usually small. My new invention may also be constructed as a so-called table machine, which is not intended to be transported like a piece of hand luggage, but which is placed on a table for playing and may easily be carried about the house from one room to the other.

My new double diaphragm loudspeaker unit may obviously be used for radio reproduction, and in other connections where loudspeaking reproduction is desired. On account of an oiiicial requirement of division, I do notli'erein make any claims to the loudspeaker unit per se, which formsthe subject matter of at least one divisional application.

I claim as my invention:

1. A portable electricphonograph conipris- 9 ing a carrying case constructed of twoshallow box-like sections arranged to provide two compartments side by side, phonographic mechanism in the compartment of one section, said mechanism including an electric reproducer, a flat frame pivotally mounted on the other section of the case so as to swing ii to upright position, a loudspeaking diaphragm and a driving unit therefor mounted on said frame, electric transmission apparatus in the compartment of said other section and operatively' connected to said reproducer and drivingxunit, releasable means on said case for rigidly holding said frame in raised position during the operation of said diaphragm, said frame and the parts carried thereby being ad- Justable into horizontal position in said other section to permit closing of the carrying case, andmeans for closing said box-like sections to form a completely closed case.

2. A portable electric phonograph comprisng a substantially rectangular carrying case having a transverse partition to provide two box-like sections side by side, a lid hinged to said case to cover both sections and thereby form a completely closed carrying case, phonographic mechanism in one of said sections. said mechanism including an electric repro ducer, a frame pivoted to the other section so as to be moved into upright and horizontal position, a loudspeaking diaphragm and a driving unit therefor mounted on said frame, electric transmission apparatus in said other section for operatively connecting said reproducer with said driving unit, and means whereby said lid when open holds said frame provide two compartments side by 'side,

phonographic mechanism in the compartment of one section, said mechanism including an electric reproducer, a movable cover mounted on the other section to close the compartment thereof, electric apparatus mounted in the last-named compartment, a flat frame pivoted to said other section above said movable cover, a tensioned loudspeaking diaphragm sheet stretched on said frame, a driving unit for said diaphragm also mounted on said frame, means on said other sectiomadapted to engage said frame and normally hold the same within said section parallel to said cover, said frame and the arts carried thereby be- -ing movableinto 'su stantially upright position for operation of the diaphragm, means for so connecting said apparatus that the electric impulses of said reproducer are amplified. and transmitted to said driving unit,

releasable means on. said case for rigidly holding said frame in raised position during the operation of said diaphragm, means whereby ,said box-like sections are closable to form a completely closed case, and means for supporting a stack ofrecords in the closed case, said records being automatically rendcred accessible when the case is opened.

4. A self-contained portable electric phonograph comprising a substantially rectangular carrying case havin a transverse parti tion to provide two flat ox-like' sections side by side, a lid hinged to said case to coverbothv sections and thereby form a completely closed carrying case, phonographic mechanism in one of said sections, said mechanism including an electric reproducer, a cover hinged to the other section below the top edge thereofto form a normally closed compartment, electric apparatus mounted in said compartment,

a flat frame pivoted to said other section above said cover, a loudspeaking diaphragm and a driving unit therefor mounted on said frame, said diaphragm consisting of a tensioned sheet stretched across said frame, means for so connecting said apparatus that the electric impulses of said reproducer are transmitted to-said driving unit, said frame and the parts carried thereby being movable into substantially upright position for operation of the diaphragm and movable into horizontal osition closely above said cover to permit c osin of the lid, means whereby said frame is hel against movement when the lid is closed, and means on said lid for supporting astack of records above the motor-- board in the phonograph section of the case.

' 5. A hornless electric phonograph comprising a cabinet having a lid, lo'udspeaking mechanism supported in said cabinet independently of said lid, said mechanism being a flat unit having a pair of diaphra ms constructed to accentuate different ban s of frequencies so as to cover practically the whole range of musical sound, means carried by said casing for adjustably supporting'said flat unit to permit closing of the lid, and electric reproducing means for simultaneously operating said diaphragms.

6. A portable. electric phonograph comprising a carrying case provided with'a hinged cover, a frame pivoted to said case and normally lying flat therein to permit closing of the cover. said frame being movable into substantially u right position, a

pair of loudspeaking diap ragms carried by said frame, electric reproducing mechanism for operating said diaphragms, and means connected to said cover for holding said frame in upright position during the operation of the diaphragms.

7. ,An electric phonograph comprising a case having a top lid hinged thereon, a frame pivoted to said case independentl of said lid and normally lying flat in sai case beneath the lid, a loudspeaking diaphragm carried by said frame, means for automatically raising said frame into substantially upright position when the lid is opened and holding the frame in such position, said frame automatically moving into horizontal position when the lid is closed, and electric reproducing mechanism for operating said diaphragm.

8. An electric phonograph comprising a case having a top lid hinged thereon, a frame pivoted to said case independentl of said lid and normally 1 ing flat in sai case beneath the lid, a lou speaking diaphragm car- .ried by said frame, a collapsible connection between said frame and said lid for automatically raising the frame into substantially upright position when the lid is opened, said connection permittin the frame and the lid to swing down on their respective pivots into horizontal position, and electric reproducing mechanism for operating said diaphragm.

' 9. A portable electric phonograph com rising a carrying case having two shallow 0xlike sections arranged side by side, phonographic mechanism in one section, said mechanism including an electric reproducer, electric loudspeaking mechanism in the other section operative'ly connected to said reprographic mechanism in one section, said mechanism including an electric reproducer, electric loudspeaking mechanism in the other section operatively connected to said reproducer,

means for closing said box-like sections; to form a completely closed case, said loudspeaker mechanism being a flat hornless structure with a direct-acting diaphragm and arranged to permit closing of the case, and means in one of said sections for supporting a stack of records Without interfering With'the closing of the case.

11. A portable electric phonograph comprising a substantially rectangular carrying case-having a transverse partition to provide two box-like sections side by side, a lid hinged to said case to cover both sections and thereby form a completely closed carrying case, phonograph-1c mechanism in one of said sections, said mechamsm lncluding'an electric reproducer, a frame pivoted to the other section so as to be moved into upright and horizontal position, a loudspeaking diaphragm and a driving unit therefor mounted on said frame, electric transmission apparatus in said other sectionfor operatively connecting said reproducer Withsaid driving unit, and releasable means for bracing said frame in upright position in front of the open lidduring the operation of said diaphragm, said lid acting as a deflector of sound produced by said diaphragm, said frame and the parts carried thereby being movable into horizontal position in the case to permit closing of the lid.

12. A self-contained "portable electric phonograph comprising a pair of flat box-like sections hinged together transversely so as to fold against each other to form a closed carrying case, phonographic mechanism in one section, said mechanism including an electric reproducer, loudspeaking mechanism in the other section, means for transmitting the electric impulses of said reproducer to said loudspeaking mechanism, said phonographic mechanism and lou dspeaking mechanism being so arranged as to leave a shallow space or chamber' between them'when the sections are closed, and means for sppporting a recordholding tray or box in said shallow chamber.

ADOLPH A. THOMAS.

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