US2154093A - Phonograph - Google Patents

Description

,April 111939. w. H. Hun-ER I PHONOGRAPH Filedr Jah. 25, 19,57

Patented pr. 11, 1939 j UNITED STATES PATENT oFFicE 2.154,09?.Iv l

PnoNoGRArn William H. Hutter, Chicago, Ill., assignor, by mesne assignments, to Rock-01a Manufacturing Corporation, Chicago, Ill., a corporation of Delaware Application Januaryl z5, 19st, `serial No. 122,153

4 Claims. This invention relates to i improvements in phonographs and more particularly to improvedV mounting means for the playing arms thereof.

Multi-record phonographs of, for example, the selecting type, are employed in business establishments for the entertainment of guests. Under those conditions, they are frequently subjected to vibrations which aretransmitted to the styluses or the needles of the machines and, therefrom im through intervening mechanisms or circuits, t

the soundvamplifiers thereby impairing the quality of the reproduction. It is an object of the present invention to provide mounting means for playingarms o phonographs which, while afl fording the necessary horizontal swinging movement .of the arms during the playing of the records and the pivotal movement of thearms to facilitate changing needles, insulates the arms from vibrations generated by the mechanisms of the Vmachines as well as extraneous vibrations transmitted to the machines,` and thereby avoid the transmission to the needle of such foreign vibrations as impair the quality'of the reproduc-A tion. .I Another object of the invention is to provide muting means, preferably carried `by the playing arm,"for preventing thek reproduction of noises or sounds such as amplifier hums during intervals when no record is in lplaying position on the turntable.

Figure 1 is .a perspective'view of a. multi-recordl phonograph, the present improved mounting means for the playing arms being embodied therein; Figure 2 is an enlarged, broken, detached perspective view of a playing arm and associated improved mounting means; l

Figure 3is 'a vertical sectional view taken on line 3-3 of Figure 2; and

Figure 4 is a horizontal section taken on line 4-4 of Figure 3.

In the drawing, I0 indicates generally a multirecord phonograph of the record-selecting type and is provided with a turntable `I I for rotating the records during the playing thereof. In Figure 1 of the drawing a plurality of record carriers I2 are shown which, by suitably driven mechanism, are movable selectively to cooperate with the turntable in positioning their respective u records in playing position. Machines ofthe type mentioned generally are provided with coin control mechanism, such as is indicated at I3, and buttons or other selector control means I4 whereby a patron may deposit one or more coins and press a corresponding number of buttons I4 5 to effect the playing in succession of the selected records.

Disposed in operative position with respect to the turntable is a playing arm I5 shown in detail in Figure 2. The forward ends ofthe playing 10 for converting the Vibrations. imparted by the record to the stylus or needle I8 into electrical 20 impulses which, by means of suitable conductors I9, are transmitted to the amplifier of the machine, not shown. The'playing arm I5 adjacent the rear end is'so mounted that it swings horizontally to enable the stylus I8 to follow the sound 25 grooves or tracks of the record being played and can also be moved about a horizontal pivot for a. purpose to be more fully described presently.

The form of mounting means selected for the --purpose of illustrating the invention comprises a 30 'hollow spindle ory shaft 2l),A to the upper end of which is attached a bracket 2l that is provided with opposite upstanding arms 22. In this embodiment of the invention, horizontally disposed pivot pins 23 are threadedly received in openings 35 in the arms 22 for .adjustment with reference to retainermembers 24 and may be releasably locked in an adjusted position by suitable means illustrated at 25 in Fig. 3. Interposedbetween each retainingmember 24 and a side wallof playing 40 arm I5 is a vibration absorbing or insulating member 26. .The insulating members 'are of. any suitable cushioning material, such as rubber for example, and in the form shown are of blocklike shape. 'I'he members 26 are seated at their 45 outer ends in the retainer members 24 and at their inner ends in cooperating retainer members I 21, attached to or formed integrally with the v'ertical side walls of the playing arm I5.

The upper ends of the arm 22, as shown in Figs. 2 and 3, may be connected, if desirable, by a yoke 28 to support the upper ends of the arms against outward displacement as the pivot screws 23 are adjusted.

. The members 26 are of such size that they ade- 55 quately sustain the playing arm, but being of cushioning or vibration absorbing material, they provide in eEect a floating support which insulates the playing arm and needle from vibrations set up in, or transmitted to, the shaft 2,0 by the mechanism of the machine and such vibrations as may be' imparted thereto from extraatneousv The insulation of the playing arm from.

sources. such vibrations, which' would otherwise, to-some extent, be impartedto the stylus.` I8 and thus detrimentally aifect the record-imparted vibratory movements of the stylus, improves the quality of reproduction of the instrument.`

Multi-record phonographs are frequently operated to reproduce a succession of records. During the changing of the records, the amplifier and speaker in such a phonograph remain ener 'gized for reproduction o f sound as soon as the needleis engaged by the record to be played. In order "to mute the pick-up device I1 and to prevent amplifier hum during the changing from one record to another or just prior to the playing of a record after the phonograph has been turned on, the bracket 2l is provided with a contact carrying member 29 carrying an electo the bracket vand. hence to the phonograph chassis. Cooperating with that grounded contact 30 is an electrical contact 3I on a resilient contact carrying member 32 having a mounting iiange 33secured by suitable means 34 tothe playing arm I5 and electrically insulated therefrom by suitable insulation 35. That contact carrying member 32 is electrically connected to one of the conductors IB as shown at 345 in Fig. 2,'and is operable bythe playing arm I5 to move the contact SI into engagement with the grounded contact 30 upon the completion of the .playing of a record and to maintain the engagement until the next record is brought to playing engagement with the needle I8. Thus the pick-up device I1 is grounded or short-circuited during idle periods. table II is of the reciprocable type Aand in the playing position, the record on the turntable is brought up to engagement with the needle I8 and continues its upward movement to swing the playing arm I5 about the pivot pins 23 a distance suicient to open the contacts 30 and 3i. After playing, the turntable bearing the played record is lowered, whereupon the playing arm swings downwardly about its pivot pins 23 closing the contacts 30 and 3I to ground the y pick-up until the next record is brought to playing engagement therewith. It will thus be seen that during the changing of records vand other,

As illustrated in Fig. 1, the turn- While `I have disclosed an embodiment of my improvements for the purpose of illustration.

it-will b e apparent that various changes of conv struction and arrangement 0f parts llly be I8- i sortedto 'without departing from lthe spirit .of

the invention as defined by the appended claims.

I claim: A A

1. In a phonograph, a playing arm, mounting means therefor comprising a pair of supporting members disposed on opposite sides of said arm,

4a pair of socket members attached ltosaid supporting members, a second pair of socket members attached to the sides of said arm adjacent said supporting members and spaced from said rst pair of socket members, one pair of said socket members being pivotally mounted, and

vibration insulating members each extending between and engaged at the ends thereof only by the respective socket members'and being mutually capable of supporting said arm in operative position. i

2. The combination with a playing arm of a phonograph. of horizontally swingable mountl ing means therefor, and means for securing said arm to said mounting means for pivotal movement with respect theretocomprising a pair of pivot members spaced laterally of said arm and resilient members of vibration absorbing mateportions of said insulating means to said arm and swingable member comprising spaced retainer members for I said portions.

' 4. 'I'he combination with a playing arm of a phonograph comprising-.a member swingable on a vertical axis and having a pair of vertical supporting members spaced laterally of 4each side of a rear portion of said arm and means interposed between the sides of said arm and the respective vertical supporting members for pivotally attaching lthe arm to said supports for movement ona horizontal laxis comprising a' pair of vibration insulating members each provided with retainer members at the endsthereof, the retainer members of each insulating member being spaced apart-by unconned intermediate'portions of the'respective Vinsulating members whereby the transmission of said vibrations from said supporting members to said arm are inhibited.

Images