US2296870A - Sound recording and reproducing - Google Patents

Description

Sept. 29, 1942. y B. A. PRocToR ET Al. I 2,296,870

SOUND RECORDING AND REPRODUCING l5 Sheets-Sheet 2 Filed July 8, 1958 ATTORNEYS Sept. 29, 1942. B. A. PRocToR ET AL, 2,296,870

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B. A. PROCTOR ET AL SOUND RECORDING AND REPRODUCING Filed July 8, 1938 15 Sheets-Sheet 5 IN VENTORS Buffa/1 Afroc for and Fwd/'nana' C. W Thiede BY' Oka-cav VL W/ ATTORNEYS sept. 29, 1942. "B, A. PRQcwR Em. 2,296,876y

SOUND RECORDING AND REPRODUCING Filed July 8. 1938 l l 15 Sheets-Sheet 6 ATTORNEYS Sept., 29, 1942.

B. A. PROCTOR ET AL.

SOUND RECORDING AND REPRODUGING Filed July 8, 1958 l'sneetS-sheet fr 5V @may 1- ATTORNEY5 Sept., 29, w42.. a. A.PRocToR ET AL 2,296,87@

SOUND RECORDING AND REPRODUCING Filed July 8. 1938 15 Sl'xeebs-f-Sheec.- 8

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SOUND RECORDING AND REPRODUCING Filed July s, 1958 15 sheets-sheet 5 ATTORNEYS Sept` 29, 1942 B. A. PRocToR ET AL 2,296,870

SOUND RECORDING AND REPRODUCING Filed July 8, 1938 l5 Sheets-Sheet lO I l I l 1 l I l l ffy/1 INVENTORS Ear-fan AProco/i and Ferm/fand C W Th/ede 'y HY ATTORNEYS B. A. PROCTOR ET AL.

SOUND RECORDING AND REPRODUCING ATTORNEYS Sept. 29, m42., A BAA. PRoc'roR ET AL. 2396,37@

SOUND RECORDING AND REPRODUCING Filed July 8, 1958 15 Sheets-Sheet l2 BY @ma .9L/lu@ ATTORNEYS Sept 29, 1942- B. A. PROCTOR ET AL SOUND RECORDING AND REPRODUCING Filed July 8, 1938 15 Sheets-Sheet 13 www@ ATTORNEYS Sept. 29, 1942. B. A. PRoc'roR ET AL 2,296,870

SOUND RECORDING AND REPRODUCIG I Filed July 8, 1938 v l5 Sheets-Sheet 14 l y I I Z Y H424. 6E Il, j

5f/l 95 w f Barron A. Proggy 59115 ferd//M/d C W Thiede 5) "urgaa Yl` v ATTORNEYS SePt- 29 1942- B. A. PRocToR ET AL 2,296,870

souND RECORDING AND REPRODUGING Filed July 8, 1958 l5 Sheets-Sheet 15 Patented Sept. 29, 1942 l SOUND RECORDING AND REIRODUCING Barton A. Proctor, Larchmont, and Ferdinand C. W. Thiede, Hempstead, N. Y.,aassignors to B. A. Proctor Company, Inc.. New York, N. .Y., a corporation of New York Application July 8, 1938, Serial No. 218,082

\-' 30 Claims.

This invention relates broadly to sound recording and reproducing, and more particularly to machines and records adapted to be used in office work for the dictation and transcription of'letters, memoranda, etc. The invention involves various features of special utility for dictation purposes, and also many features of more general application.

In accordance with prior commerical practice,

dictation machines are designed to be used with cylindrical wax records. l,These records are expensive,. bulky and fragile. that the records be re-used, and hence it is necessary to provide a shaving machine for shaving the transcribed records to prepare them for reuse. This involves an added investment for equipment, consumes the time of the operator for performing the shaving operation, and puts an end to any further possibility of$reference to the shaved record for verification purposes. Valuable oilice space is consumed by rebords waiting to be shaved.

It is not feasible to keep any substantial number of unshaved records on hand for reference, both because that would involve an inordinate investment in records, and because of space requirements for storing the records. The records must be handled very carefully at all times because they are extremely frangible. The dropping of a blank or transcribed record involves destruction of the record, but the dropping of an untranscribed record is likely to be much more serious because of the loss of the material recorded upon it.

Important objects of the present invention have to do with the overcoming ofthe above mentioned drawbacks by providing an improved record which is small in bulk, infrangible, and so inexpensive that it may be lfiled away, if' desired, after it has been transcribed, and may be eventually discarded without re-use; and by providing a recording and reproducing machine capable of use with the improved record in a highly eicient and satisfactory manner.

' The improved record is desirably in the form of a through-deform-able disc of tough, flexible material, adapted to have a sound record scribed upon,it, and of no greater thickness than an ordinary sheet of letter paper. Such -a record has clear advantages of cheapness, small bulk, and infrangibility, but presents serious problems in the matter of its use for recording and reproducing purposes. l

The illustrative, through-deformable record becomes indented through by the formation of Economy demands K the sound record groove, and tends to curl. When simply spread out flat it has no substantial rigidity, atleast no rigidity suflicient properly to transmit an adequate and positive drlv ing force to the cutting point. The record also presents difliculties in the matter of securing a properly cut sound record, both because of its tendency to transmit machine noises and vibrations into the record track, and because of its tendency to impose upon the recordj track grain pattern characteristics of any solid backing or platen that may be opposed to .the stylus. The' generation of background noises at reproducing also presents a diiiiculty. the present invention have to do with the overcoming of these diiculties.

Briefly, the illustrative machine desir-ably inlcludes a mounting spindle, upon which a thin,

flexible disc record may be impaled, and opposed feed rollers spaced from'the spindle for engaginga opposite faces of the record and driving the record about the spindle axis. The spindle is mounted upon a carriage, and is connected to drive a. feed screw, which is also mounted upon the carriage. Rotation of the record is transmitted to the spindle and thence to the feed screw. The feed screw cooperates with an axially immovable half-nut, which is adapted to be engaged with and disengaged from the feed screw at will. When the half-nut is engaged with the feed screw the carriage is caused to be moved axially of the feed screw and to move the record spindle away 'from the record driving rollers, so that that zone of the record which ex` tends radially between the spindle and the record driving rollers -is maintained constantly under tension during the driving of the record.

A stationary stylus is mounted to act upon the record in the tensioned radial'zone of the record whichextends between the spindle and the point of contact of the record with the driving rollers, and closely adjacent to the latter point. The fact that the stylus acts upon a portion of the record which is constantly under tension is a very important one in connection with the control of the record and also with Important objects of f points of view.

support, and cooperating guides are provided for maintaining the record in substantial conformity with the curved support. This marmer of supporting the record is importantI from many from a point starting near the center and is caused to progress outward toward the circumference of the record. As the groove progresses the record becomes indented through, and these indentations constitute a multiplicity of i'lne corrugations which are disposed crosswise of the radius of the record which join the axis of the spindle with the point of engagement of the feed roller, and which are bent' downward at opposite sides of such radius. The maintaining of the record thus bent, together Withthe fact that these fine corrugations are present, causes the radial zone of the record engaged by the spindle, the stylus, and the feed rollers to be quite rigid. This is a very important point in connection with thesecurement of a firm and adequate driving of the record past the stylus.

'I'he spiral record groove is cut.

The curved support has the further advantage that it acts as a brake upon the record. When the driving rollers are separated, the record and the parts driven by it, which are all of very slight mass, are caused to come instantly to rest. The curved support for the record has the further advantage that one horizontal dimension of the machine may be considerably shorter than the diameter o a record.

The curved support also takes the curl out of the record and causes all portions of the record to be controlled in an orderly manner at all times.

The fact that the record and the parts which rotate in uniform relation to the record have relatively slight mass and slight inertia has an important bearing on the accurate production of the desired variable rotary speed of the record, regardless of whether the record is started and stopped from time to time.` The uniformly running motor and the relatively massive parts which run in uniform relationto the motor are not perceptibly influenced by the gradual and slight change of load which results from the progressive change in rotary speed of the record. From this point of view it is an important point that the need for a turntable is obviated. The obviation of a turntable is also very important from. the standpoint of securing instantaneous stopping of the record and instantaneous acceleration of the record to 'the desired speed after a stop.

The recording operation does not start at the very center ofthe record but at a substantial distance outward from the center. 'I'he central portion of the record is without indentations and, therefore, without stiiening corrugations. It is a feature of the invention, however, that this" central area of the record has aftixed to it a label which both affords a. writing medium for receiving notes relative to the material recorded, and a reinforcement for the central area of the record to maintain that area dat and substantially more .rigid than the surrounding area. Prior practice has involved the provision of `a separate, loose memorandum slip for association with each record, but no provision has been made for assuring the -maintenance of such association. No claim is rnade herein to the record, per se, the record being claimed in continuation in part applications of Barton A. Proctor, Serial No. 438,713, filed April 13, 1942, for Records for recording andreproducing sound, and Serial No.

436,243, led March 26, 1942, for Records for recording and reproducing sound.

' The machine further embodies means for keeping out of the sound track extraneous noises, such as scratch noises, background noises, and noises originating from the vibration of various machine parts. It is not possible to produce a satisfactory sound groove in a. thin, plastic material supported directly on a hard metal surface without developing background noise in the record caused by the grain pattern of the material of which the supporting base is made. In order to avoid such a result the machine of the present invention is made to include a platen in the form of a resilient cushion for engaging the back of the record material.

It is a further feature of the invention in accordance with an advantageous form thereof that not even the resilient platen is directly opposed to the stylus, but that the stylus is rather caused to engage the record material under tension with the record held in bridging relation to supporting points of the platen.

In reproduction it is important that the record material, at the point of contact with the reproducing stylus, be not allowed to run in frictional engagement with any underlying material because such friction will inevitably introduce objectionable noises into the `reprcducer pickup.

Such defective operation'is"'avoided-in the machine of the present invention by making the platen free to roll in contact with the record material.

The machine desirably involves both electrical recording and electrical reproducing, separate styluses being used for the two purposes, and separate circuits being established, according to whether recording or reproducing is in progress. It is a. feature of the invention that mechanism is provided under the control of a single' operand' 'because of the delicate and accurate responsiveness tothe reproducing stylus which may be secured.

In accordance with still another featureA of the invention, provision is made in the electrical part of the machine of an overload protective device for limiting the amplitude of the electrical vibrations, and hence of the reproduced sound. This device desirably consists of a glow tube connected inductively to the input of the recorder circuit and to the output of the reproducing circuit. A circuit including such a tube has the characteristic that it will absorb no energy from the primary or input circuit with which it is inductively coupled unless and until the conditions of the primary circuit are such as to induce a potential in excess of a denite value. When such deiinite value is exceeded, however, the tube will glow, and the circuit will substantially modify the current owing in the primary circuit with which the glow tube circuit is coupled.

No claim Iis made herein to the recording and reproducing units and the electrical apparatus combined and associated therewith because that subject-matter is claimed in our continuation in 2,296,870 Y 3 part application Serial No. 436,244fled March trical connections between the various parte of 26, 1942, for Sound recording andreprodilcing; the machine.

A further advantageous feature residesin the Referring to Figs. l to 4, there is provided a fact that the machine embodies a record storage casing in which the component parts of the decompartment. This compartment desirably exvice are suitably mounted and supported, said tends along the front and bottom of the main casing. comprising a rear wall, 53, base 54, a` front frame of the machine,` arid is rather thin. It is wall 55-which is shorter than thev rear wall, a top capable, however, of holding a very substantial wal1'56 having a depending portion 51, and end number of thin, flexible disc records, and the recwalls 58 and 59. The top wall extends downords, because of their flexibility, can be very wardly as shown at B0 in Fig. l to provide a flat readily caused to follow the, curvature 'of the -surface 1I at a lower level to accommodate cercompartment as they are introduced into it or tain controls tobedescribed later. Also asshown withdrawn from it. l. lin Figs. 1 and 2 the end wall 58 is lower than end It is a further feature @that provision is made wall 59 and at its top level a narrow shelf or of a retractible reference scale, cooperative with bracket 6I, secured to the rear wall 53, extends the" record spindle for indicating to the user of horizontally to provide a support for the hinge the machine the points on the record at which block 62 secured thereto by screws 83. A frame 64,

j arrows;

' the line Ill-I8 of Fig. 4;

`view of the machine;

various matters are recorded. having the-spaced apart parallel arms 85 to the Other objects and advantages will hereinafter outer ends of which a graduated scale 88 is beappear. 4 20. cured, is hinged to block 62 by the pivoted sup-- Fig. 1 is a front elevation'ofthe machine; ports 61. For the purpose .of supporting the Fig. 2 is atop plan viewof the machine; scale when it is moved back on its hinge in order Fig. 3 isa side elevation as view from the left to insert a record, a rearwardly extending suphand end of Fig. l; port arm 68 is secured to frame 6I, its lower end Fig. 4 is a vertical side view insection, the- 25 being bent over to PrOVide RSUDPOI 09 which enon the line 4-4 of Fig. 8; gages and rests on the -block 62v when the scale is Fig. 5 is a perspective view of a cam unit which thrown back. It will be obvious from Fig: 2 that. effects the setting of the reproducer and the rewhen the scale is thrown back, a large open area eerder; is presented at the top of the casing for the Fig. 6 is a side elevation as seen from the right 30v insertion of a thin, flexible record 10. to be later hand side of Fig. 1,\with the right hand end plate described. Also as .shown in Fis. 2,`the nat porremoved;

Fig. 7 is a sectional side view taken on the line Shown at 'l2 and terminates at 13 so as to leave 1--1 of Fig. 8 and looking in the direction of the aispace between it and the front wall 55. This space forms part of an opening or slot .14 ex- Fig. 8 is a sectional front view taken on the tending across the front 0f the Casing and 91'0-I llnes 8-8 of Fig. 6; i vided as a storage place for usedor unused rec- Fig. 9 is a view similar to Fig. 8 with some of ords. The extended portion 12 of the casing tOD the parts removed and showing the carriage inv also has a slot 18 through which a switch handle a different position; 40 15 of an on-oi switch 2 (see Fig. 25) extends, Fig, 10 is a, sectional top plan view taken en and also accommodates a volume control knob 50. Theopening 14 extends between the corner posts Fig. l1 is a fragmentary, sectional, top plan .'11 Which engaged the end' plates and $10118 the length of thisopening the front wall and base are connected by a thin concave strip 18 which serves to guide the record as it is inserted for storage.

figure being taken Fig. 12 ,is a vertical section taken on the line l2-i2 of Fig. 18;

Figs. 13 and 14 are detail front views in sectiony The vertical portion ofthe storage space is dcshowing the relative positions between the refined at the rear by an upright wall-.J9 which is producer arm and the lifting arm therefor; convexly curved near its lower end opposite the Fig. 15 is a fragmentary top plan view in sec- 50 strip 18 and is secured to the front of a wide horticn, taken on thence ls-ls of Fig. 16,.,showing izontal member 80 which supports the electric the reproducer and the recorder and their shiftmotor 40 and other parts of the driving mechaing mechanisms; nism, the supporting member 80 extending to Fig. 16 is a sectional side view taken on the rear wall 53.v As shown more clearly in Fig. 8. line lS--I 6 of Fig. 15 and looking in the direction 55 member 80 is secured to and supported by a genef 'the arrows; erally rectangular shaped bar 8| which extends Figs. 17 and 18 are views similar to Figs. 15 and across the other end. The larger parts of the end 16 respectively but show the renroducer in its plates 53 and 59 0f the casing are perforated active position, the section of Fig. 17 being taken with holes 83 so as to Permit Circulation of air on the line i1l1 of Fig. 18; 60 and dissipation of the heat generated in the mo- Fig. 19 is a view similar to Fig. 18 but shows the 1501' and amplifierunit to be described later. parts shifted to render the recorder eiective; These perforated end plates are milde Separate Fig. 20 is a fragmentary sectional side view,l of from the main body portion of the casing and the right hand end of Fig. 6, showing the 'parts are secured in position by screws 84 and 85. In

, tion 1l of the top of the casing is extended as shifted to their effective positions; inserting a record in the vertical portion of the Fig. 21 is a detailed front view in section of slot or storage space 1I when its edge meets the the record platen roller; COIICRVB Strip 73 it slides along 'this strip and is Fig. 22 is a section view of a fragment of the guided into the horizontal portion 86 cf the open roller shown in Fig. 21; and a portion of the space between the flat support 80 and the botrecord bearing thereon; f 70 tom casing wall 54. Fan blades 81.are prefer- Fig. 23 is a top plan view of the record; ably secured to the motor shaft to create a cir- Fig. 24 is a sectional detailed view of the means culation or current of air through the casing. whereby the record is held connected to the As shown more clearly 'in Fig. 4, a curved sheet` spindle; and of thin metal 88 formed into the shape of a Fig. 25 is a circuit diagram showing the elec- '.'5 transverse section of a turtle back is provided to properly support the record 10 from below. the

' under surface of the record, frictionally engaging member 08 as the record rotates. 'I'he turtle back is supported at vthe front by its lower edge resting on the curved portion of strip 10, a

spacing `member 89 serving to hold these memalong its top is provided with a slot 94 (see Fig.'

2) to permit the passage of the record spindle 95 therethrough. A bracket 91 secured to the inner surface of wall 19 and extending along the top thereof serves to partially conceal the front p0rtion of record support 88, its curved rear surface 06 being spaced from 88 to provide proper clearance space. f

RECORD DRIVE Referring to Figs. 6, 8, and 11, the shaft 98a of motor 40 is provided with a pulley 98 over which passes belt 99 engaging pulley |00- secured near the end of a shaft |0| carrying a friction drive wheel or feed roller |02 at its inner end, the latter wheel directly engaging the lower face of the record to cause its`rotation. A partition wall |03 extends across the casing near one end and having a slot 03a therein throughl which shaft |0| passes freely, this shaft being journaled in a pair of spaced apart bearing lugs |04 extending from a stationary supporting bracket |05 which has parallel end Walls |05 and |01 extending toward therear of the easing, end wall |06 lying along partition wall |03 and wall |01 having an aperture |08 to permit free passage of a rod |09 forming part of the record carriage |09a. As shown in Fig. 7, bracket ported by the oppositely disposed channel bars ||0 and the spear bar l||0a. A pair' of guide members or rods 5| and 52 (Fig. 8) are provided to guide the record carriage, one end of rod 6| being supported in the end wall |06 and its other end in an arm I la of a bracket located near the end of the casing. 'I'he outer end of rod 52 is supported by bracket ||I and its inner end by bracket |05.

The record carriage comprises a frame H2 secured to the left end of the hollow rod |09 and a depending arm ||3 secured at its right hand end, a shaft ||4 being journalled .in frame ||2 and arm ||3 and being threaded for that portion of its length between these members. shown in Fig. 4, rod 52 passes through a notch i |2a in the lower end of frame H2 and rod 5| through a bore near its top whereby the frame is supported and guided, rod 5| also passing through a bore in arm ||3 near its top to support and guide it. Frame 2 in its hollow portion houses a gear 6 secured to shaft or screw `||4, gear ||6 engaginga skew gear ||1 secured to the record spindle 95. Frame ||`2 is provided at one.end with two projecting bosses ||8` to which the ends of a, transversely extending thrust member 9 are secured by screws |20. The end of threaded screw shaft ||4 is slightly bored to receive a steel cball |2| which also abuts against member ||9 so that the endwise motion of shaft |I4 is transmitted through the ball to |05 is suprear wall 53. 'I'he shaft the record carriage. In order to cause endwise motion of the screw shaft ||4 upon its rotation by the record spindle and gears ||5 and described, an arm |22 is secured to a shaft |23 which may' be rotated slightly by means to be described later, the end of the arm being provided with a threaded portion |24 which may be brought into engagement with the threads on shaft ||4. .When so engaged, arm |22 serves as a stationary nut, causing endwise motion of shaft H4. A coil spring |24a secured to the end of the arm and to a stationary pin |25 biases the arm towards engagement with the shaft ||4 (see Fig. 7). A short slot |26 (Figs. 7 and 8) is provided in record support 88 through which friction wheel |02 extends slightly in order to engage the record.

Referring now particularly to Figs. '7, 8 and 11, a frame |26 is pivotally mounted on a shaft |21 and comprises a cross bar |2811r having spaced apart lugs |28 in which is journalled a shaft |20 which carries at its end a friction wheel |38 mounted to engage the upper surface of the record 10 directly over wheel |02. 'I'his shaft is driven by a friction wheel |30', arranged to engage the hub portion i0|' of pulley |00, the peripheral portions of wheels |02, |30 and |30' preferably being formed of rubber. An arm 3| bent as shown in Fig. Il is secured to bar |28a of frame |26, a coil spring |32 having one end secured to the arm and its other end to a pin |33 carried by a bracket |34 attached to the rear wall of the casing. When it is not desired to drive a record, the parts are in the position shown in Fig. 7 with wheel 30 elevated above the record, and wheel |30' not engaging driving hub- |00'. As-shown, a vertical arm |35 is secured to a shaft 35a carrying a gear |36 which meshes with gear |31 secured toV a vertical shaft |38 supported by a bracket |34, secured to the |38 passes through the top portion 1| of the casing where it is pro-` vided with an operating handle |39. When the handle is inthe neutral position shown in Figs. l, 2 and 7, arm |35 serves to hold wheel |30 elevated so that the record is not driven; when handle |39 is moved either toward the right to record or to the left to reproduce, arm |35 moves up, as in Fig. 20, to allow spring |32 to depress and hold the wheel |30 in engagement with hub |00' and wheel |30 record which is then driven by the wheels |02 and |30. f

To provide a ready means for the operator to stop a record at any time independently of the handle |39,van upstanding arm |40 is secured to the bar |28a of the frame |26 and adapted for engagement by a head |4| (Fig. 7) secured to the end of a exible-Bowden wire |42 which is enclosed by the usual nexible casing |42'. A bracket |43 projected from the inner wall of the casing serves to support one end of the wire |42. The other end of the wire is attached to a. plunger |44 terminating in a knob |45, the plunger being slidable in a casing |46 having a hand or nger grip |41 and a bayonet slot |48. A compression spring |49 engaging the end wall of casing |46 and the end of plunger |44 biases the Bowden wire to its outer position, permitting wheel |38 to engage the record. To stop the record, it is only necessary for the operator to press knob |45 which will cause the head 4| to push arm |40 backwards, thereby raising idler wheel |30. The bayonet slot |46 is provided in the casing in which a pin |5| may be advanced and in rm engagement with'the asaeasvo slightly rotated, when the operator desires to. elevate wheel |30 for an extended time."

Record and its attachment .machine as heretofore described. Before use,

both faces of the record are smooth, the sound track being formed as the recording is made and causing the record to become distortedor wrin-` kled so that it is no longer fiat.

We have found by experiment that a slight coating of high melting point wax, which is applied to the surface of the record in a solution of carbontetrachloride which dries very rapidly, is desirable and acts as a stylus lubricant in the operation of drawing the groove in the record material. Alternatively, a coating formed of ethylcellulose and' wax may be employed with the added advantage that the wax does not read-- ily rub off and the heat developed in the process of recording serves to liberate the wax lubricant.

A disc of paper |52 is cemented to the upper face of the record at its center, this disc permitting notations to be written upon it for giv. ing .the positions of various matters recorded on a. record. The disc also serves to reinforce the record at the region where it is attached to the spindle. As shown, an aperture is formed through both the label and record having a plurality of inwardly directed projections |53 resembling gear`teeth.

Record spindle 95 is formed with a circular shoulder or flange |54 upon -which the center of the record rests. Just above this, a series of flutes |55 is formed into which the projections |53 on the record extend to thereby effectively transmit the rotation of a record to spindle 96.

-A hollow bushing or cap |56 rests on the upper surface of the record, its upper end being bored to receive the end of the spindle which is oi smaller diameter than the fiuted portion.

l groove |51 is here formed into which two metal balls |59 engage for thepurpose of securing a cap |59 to the end of the spindle, each ball being biased by a pin |60 secured to the lower end of a spring |6| whose upper end is secured to the cap by a screw or rivet |62. This arrangement permits ready removal of the cap and a record from the record spindle. The cap |56 has a conical shaped head |59 at its upper end, the point or apex of the cone serving as an indicator in connection with scale 66 (see Fig. 2) to indicate the position of matter recorded on the record. The recording device forms a spiral shaped sound track |63 in the record in a manner to be described.

It-ris not necessary to use the cap as a means of holding the record in place. The center hole in the record is made small enough to cause the record to be held by friction to the spindle 95. The cap, however, constitutes a convenient index member which can be readily removed to facili- 'tate application and removal of records.

Recording and* reproducing units the stylus |65 of the recording unit 30 (see Fig. 8 also). Wheel |64 is mountedl on the end of a shaft |66 journalled for rotation in a bearing member |61 which is mounted for pivoted movement on a pin |66 carried by a lug |69 of bracket |05. Shaft|66 is recessed as shown to receive a pin formed on the end of a screw |10, thus retaining the shaft in proper position axially. Member |61 is bored to receive an adjusting screw |1| which engages a threaded hole in a lug |12 projecting from the bracket |05. Cylindrical blocks of soft rubber |13 and |14 are arranged as shown, under compression, so that upon adjustment of screw |1|, wheel |64'may be slightly adjusted in position with reference to the stylus. The wheel |64 is formed of alternate laminations |15 and |16 of soft rubber and steel respectively held in place against a ange |66a by a screw |11 threaded into the end of shaft |66, the end of screw |11 being extended to form a head |11a of large diameter cooperating with the adjacent disc |16. A thrust ball |18- is seated in a recess formed in the end of the screw, and is retained in position by a spring |19 whose end is secured to lug |12 by screw |80. The stylus may engage the record directlyover one of the rubber laminations |15 to permit the sound track to be formed therein, the rubber permitting the lower surface as well as the upper surfa'ceithe record to be deformed by the action of the stylus nwhich forms the sound track by its moving sidewise. Fig. 22 shows on an enlarged scale, depressions of the sound track in the upper surface of a record and corresponding projections formed on its lower surface.

.As shown in Fig. 11, control shaft |35a passes through partition wall |09 and is journalled in the end walls |06 and |01 of bracket |05 ,and also extends through a partition wallflBZ extending across the top of the casing. The end of this shaft carries a cam unit |09 (see Fig. 5 also) which controls the positioning of the recorder 30 and reproducer 29. The recorder 30 is supported for vertical movement by two substantially parallel arms |60 and |69 connected to it by screws |06 and |6'|, the rear ends of these arms being pivotally supported by screws and |89 threaded into a lug |06a extending from wall |82 (see Figs. l5 and 16) and a lug |6911 on a bracket on the wall |02. Arm |80 carries a roller |9015 which engages a cam |9| forming a part of cam unit |99 and having a rise portion |92 which raises or lowers the/recorder and a large dwell portion |93 which maintains it in its elevated or inoperative position. The parallel supporting links serve to maintain the recorder unit in parallel position as it is raised or lowered.

The reproducer unit 29 is mounted for'both sidewise and vertical motion by its attachment to the end of a lever |90 having anoiset extension |95, the lever being pivoted loosely on a shoulder screw |96 threaded into the inner end of another lever |91 which is in turn pivotally supported for up-and down movements on a cylindrical extension |98 (Fig. 15) formed on its -inner end, this extension engaging a bore made in an enlarged hub portion |99 formed on the end of a third lever 200. A vertical screw 20| passing through a bore formed in the hub |99 and threaded into the iixed bracket |90 serves y as a pivotal support for sidewise motion of all three levers. A spring 203 (Fig. 17) having one end xed to a pin 204e on hub portion |99 and its other end to a fixed pin 204 biases the levers toward the camunit |83. The levers |91 and 200

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