US1855933A - Acoustical instrument - Google Patents

Description

April 26, 1932. MALDEN 1 8 5,

ACOUSTI CAL INSTRUMENT Filed April 7, 1927 3 Sheets-Sheet l N Hi t INVENTOR.

April 26, 1932. M. ALDEN 1,855,933

ACOUSTI CAL INSTRUMENT M. ALDEN ACOUSTICAL INSTRUMENT April 26, 1932.

Filed April 7, 1927 3 Sheets- Sheet 3 x H or f ia I Patented 26, 1 932 UNITED STATES PAT T OFFICE MILTOLT ALDEN, OF SPRINGFIELD,AMASSACHUSETTS, ASSIGNOR, BY MESNE ASSIGN- MENTS, T RADIO INVENTIONS, INC.', .A. CORPORATIDN OF NEW YORK Acous'rIoaL INSTRUMENT Application filed April 7, 1927. Serial no. 131,754.

I The one object of my invention is to produce a radio broadcast receiver in combination with an electrical quality. O

Another object is to produce a combination as described above from which the radiotuning elements and their associated component phonograph of high parts may be removed as a unit in'order that theprogram to be received may be controlled from.a distance.

. Still another object is to produce an apparatus of the type described having extremely high tonal quality both in respect to the reproduction of mechanical records and the reproduction of radio broadcasts.

My invention consists chiefly of the combination of turntable electrically driven by the type of motor frequently employed in alternating current integrating watt-meters, a governor, and a stylus operated magnetic pick-up associated therewith, a high quality amplifier for use for the reproduct on ofboth records and broadcasting, ahigh grade loud speak r' which may be of the cone type,. -2 a removab' container carrying the tuning elements and their associated apparatus, and

suitable energizing sources for thefradio apparatus all contained in one cabinet.

J I thus produce a unit in which many of the component parts are used both for radio reproduction and for record reproduction thereby considerably lowering the manufacturing cost, and due to the removable feature of the tuning element, the operation of the device as a radio receiver may be con-' trolled from a distance.

7 part of the turntable.

lly sectional front view Referring to the drawings, Fig. 1 is aperspective view of one embodiment of my invention, showing the radio control box removed from the cabinet; Fig. 2 is a detail of a part of the phonograp mechanism. e j

' Fig. 2a.is a perspective view of certain -modified details. 1 v

Fig. 3 is an elevation o f.the motor and a Fig. 4 is a partia with the cone of the speaker removed.

Fig. 5 is a partially-sectional side view of the apparatus.

' Fig. 6 is a schematic wiring diagram showing one of many possible arrangements of the transfer switch.

The cabinet-10 may be of any suitable design and provided with a number of chambers or compartments One may preferably be furnished with a loud speaker having a rill or outlet 11 at one side. An upper chamer has a hingedcover 12. The cabinet may also be provlded with an inner cldsure 13 having a recess or compartment 14- adapted to hold the tuning box 15 so that its panel 16 will be substantlally flush with the closure -13. Upon a shelf 17 in acentral compartment having adoor 12' may be mounted an audio frequency amplifier 18 which may preferably be of the type disclosed in my Patent 1,678,717. A chamber may be provided' in the bottom of the cabinet 10 for the power sources for the vacuum tubes used, here indicated as the cathode'heating battery 19 and the anode supply batteries 20 and 21,

but it should be understood that battery eliminators, motor generators, or other means of .power supply may be employed.

Theloud speaker movement 22 may be secured. to thewall 23 of the recess or well 14 and itscone-like diaphragm 22' may. be securleid 1to or behind the outer edge of the gm 1 The turntable 24, which is preferably const-ructed of aluminum, is mounted in the central cpmpartment upon the horizontal shaft 25 and this shaft may be provided with spring members such as 26 and 27 forfricti'onally engaging the'central aperture of the record 28 and holding it in place.

The disc 24 is somewhat larger than the largest record to be used and its free edge passes between the pole ti s 29, 30, 31, 32 and 33 of the edd current in uction motor drive until 34 whic ma be suitably mounted with- 5 The end of this bar when in playing position engages with the spring clips 39 and 40. This bar carries the carriage 41 which may be supported from the bar by grooved rollers 42 and 43 allowing it to move easily along the bar 37 and to swingabout this bar. De-

pending froin the carriage 41 is the stylus op-' erated magnetic pick-up 44 which should be so balanced and mounted as to cause the st lus 45 to engage the grooves of the recor 28 with proper pressure. This pick-up maybe of any suitable type such as that disclosed in my Patent 1,756,966.

The tuning box 15 is attached to the cabinet 10 by a flexible cable 46 which contains all necessary leads such as antenna, ground, battery and detector out-put leads. Of course this cable may be wound on a suitable reel. This tuning box may contain suitable radio frequency amplification and detection apparatus 51 and 52 respectively with their tuning and volume control devices which may be of any suitable type. I have shown a volume control at 47, adetector rheostat at 48 and as a tuning control, indicated at 49, I prefer to use the localized control disclosed in my copendng applications #154,689, filed Dec. 14, 1926, or 163,196 filed Jan..24, 1927.

A plate battery 53 is provided for the detector. I

A switch is provided having threepositions. In the central position all current is turned ofi. In the phonograph operating position the tubes of the audio frequency am-. pli'fier are lighted and the alternating current house line 60 is connected s'uitablyto the disc drivin magnet 34. In the radio operating position all the tubes in the apparatus are lit and the driving magnets 34 are disconnected. This switch also effects the connection of the in-put of the audio frequency amplifier to either the detector output or the out-putof the magnetic pick-up44 ap ropriately.

' n operation as a-phonograph, the bar 37 is disengaged from its clips 39 and 40, and is swung horizontally outward until arecord such as 28 can be conveniently snapped on to the shaft 25 so as, to be held against the turntable 24 by the springs as 26 and 27. The rod 37 is then swung back to engage the spring clips 39 and 40. The'magnetic pick-up 44 is raised from the record 28 and moved along the bar 37 until the stylus 45 is-opposite the outer grooves of the record. The switch 50 is then adjusted tothe phonograph position thus connecting the input of the audio frequency amplifier 18 to .the pick-up 44, connecting the motor 34 to the alternating current lines and lighting the filaments ofthe tubes of the amplifier 18. When used as a radio receiver the switch 50 is placed in the radio position, thus disconnecting the motor 34, lighting the tubes of emmas both the amplifier 18 and the control unit 15 and transferring the input of the audio frequency amplifier 18 from the pick-up 44 to the detector out-put of the radio frequency tuning unit. 1

In Fig. 2a I have shown certain modifications of details which are of considerable value. In this case, I have shown the guide rod 37 mounted behind the turntable or record holder 24. The pickup device 44 is supported by a sort of gooseneck carriage 41 which travels on this rod 37' so that the goose-neck extends around the edge of the record holder. Preferably, this guide rod 37 is inclined somewhat so that gravity may assist the movement of the pick-up in the grooves in the face of the record.

In some of the modern records the grooves are made extremely fine and consequently they are poorly adapted to the feed ofthe needle of the pickup. The inclination of the guide track serves to provide a continual,

tendency for the pick-up to move towards the center of the record, thus preventing the needle from jumping out of the groove. It has been found that records which cannot be played on the usual horizontal turntable on account of this tendency of the needle to jump from the groove, can be very well played on the vertical turntable of my invention.

In Fig. 2a, I have also shown the motor 34 and the governor 36' both mounted on a casting or frame 35' which serves tosupport the turntable shaft 25.' This arrangement facilitates construction and installation of the parts. I

The vertical record arrangement has an additional advantage in that it does not tend to collect dust and grit, which act as abrasives and tend to damage the records when they are 'iised on horizontal planev machines.

which is not possible with the usual type of swinging support.

The radio receiver with the portable control unit is claimed in my application Ser. No. 602.197 filed March 31st, 1932. I

"It should be understood that I do not wish to limit myself to the specific embodiments of my invention, as shown and described, except insofar as I do limit myself in the following claims.

I'claim:

1.- A combination radio broadcast receiver and phonograph comprising a motor driven phonographrecord holder, an electro-magnetic pick-up coactin .with a record on the holder, audio ampli ying means connected to the pick-up, a loud speaker connected to the output of the audio amplifying means,

power supply means for the amplif ing face of sai and coacting with the armature portion of the turntable for rotating the same, means for supporting a sound record on saidturntable, a pick-up device provided with a stylus for coaction with the sound record and means for guidin said pick-up device across the record.

. 'Z. A reproducing device com rising a turntable whose plane ofrotation 1s inclined more than 45 to the horizontal, means for rotating said turntable, a pick-up device having a stylus for coaction with a record supported on said turntable, a guide rod for said pick-up arranged in a. lane substantially parallel to the lane 0 the turntable but inclined to the horizontal so that gravity aids the movement of the pick-up along'said guide rod.

scribed, comprising a metallic turntablemounted on a horizontal axis, an induction motor stator having pole pieces coacting with both sides of one edge of the turntable for driving the same, a means for removably securing a sound record on said turntable, and a pick-up supported to move across the face of the record.

3. An instrument of the character described, comprising a turntable mounted on a horizontal axis, a guide rod mounted near said turntable, a carriage having a gooseneck "extension pro ecting around the'edge of the 35 turntable, and an electric pickup supported by said gooseneck extension for coaction with the record on said turntable.

4. An instrument of the character described, comprising a-turntable mounted on a horizontal axis, a guide rod mounted adjacent thereto, and inclined downwardly with relation thereto, a carriage mounted to travel on an incline on saidguide rod, and a magnetic pick-up supported by'said carriage and adapted to coact with the record on said turntable, whereby gravity assists in. the movement of said pick-up across the face of the record. Y

consisting of pole pieces and windings arranged on opposite sides of one edge of said i turntable, agovernor coacting with said turntable and a single mounting frame supporting said motor, said governor and said turntable.

6. Asound reproducing instrument comprising a substantiall' vertical turntable mounted on a substan ially horizontal axis' andprovided'witll a metallic armaturepor tion,. an induction motor stator having pole 'piecesarranged on. opposite sides of one edge of the metallic armature portion outside of the-record holding portion of the turntable 8. A combination radio broadcast receiver and phonograph including a motor driven phonograph record holder, an electric pickup eoacting therewith, a source of electric power, amplifying means and a loud speaker, a cabinet containing all of the foregoing elements, a portable control unit contalning means for controlling the tuning of the receiver and volume control means and a cable connecting the portable unit and the cabinet and swit ing means for switching the loud speaker from the broadcast receiver to the hono ra h. p g p MILTON ALDEN.

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