US1418249A - Sound box for talking machines - Google Patents

Description

A. H. GAY.

SOUND BOX FOR TALKING MACHINES. APPLICATION FILED APR. 20. 1921.

Patented May 30; 1922.

28 l i 15 IEIILLZ 18 6 'Fig. 6'. 2 0 21 STATE-S TENT orr ca.

HALBERT HARDY GAY, or LONDON, ENGLAND,

sounn BOX iron TALKING MACHINES.

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To all whom it'ma i concern: 1 v

Be it known that I, Anniiirr HARDY-GAY, a subject of the' King of Great Britain and Ireland, residing at London, England, have invented certain new and useful Improvements in SoundBoXes for Talking Machines, of which the following is a specification. I

This invention relates to sound boxes for talking machines and has for its object to increase the volume of the reproduction, and to obtain a reproduction more closely approaching the originahas regai-dstone and articulation. it

, The invention has also for its Ol)]60l3 to reduce to the minimum the hissing, and other undesirable surface noises incidental to talking machines and the like sound reproduc ing instruments. Y I r r The invention cons sts in the features of construction combination and arrangement of parts, hereinafter more fully described with reference to the accompanying drawings and claimed in the appended claim.

' In the drawings wherein like reference numerals are employed to indicate corresponding parts in the variousfigures Figure 1 is a--secti ona1fside elevation of the complete sound box. I V

Figure 2 a front elevation corresponding to Figure 1, but with the cap 22 removed.

Figure ,3 is a sectional-side elevation correspondin'gto Figure 1 but turned through an angle of 90. I

Figure 1 is a front elevation looking in the direction of the arrow in Figure 3.

, Figure 5 is a sectional side elevation showing modified connecting means for the tone arm, and

Figure 6 is an enlarged detail view showing more clearly the means for insulating the stylus bar and bracket for the fulcrum pin, from said fulcrum pin.

Referring to the drawings, an open ended circular casing 1 of metal such as brass or aluminium forming the sound box proper, and somewhat deeper than the usual soundboX, is reduced circumferentially at one end hereinafter referred to as the back end, to form a shoulder 2, and has an inwardly projecting flange 3 extending from such reduced end.

Two rings a, 4, of hollow formation and constructed of rubber are fitted in the casing 1, and are adapted to receive between them the diaphragm 5, at its edge.

A cover 6 is screwedon the other end of Specification of Letters Eatent. Pat nt d pl 30 1922 i ;App'1ieation fi1ed April 20, 1921. Serial No. 462,817. I 1

. the casing 1, herein'after referred to as the frontend, and serves to retain the rings 4 in position between it and the inwardly proecting flange 3, thefdiaphragm 5 being thereby clamped between the rings 4:. 1.

This front cover 6 has a central outwardly extending boss 7, formed with a bore 8 of tapered Or flared form, the wider end openin g directly into the casing 1, opposite to the diaphragm 5. I I I I It is preferred to form this bore, with curved wallsin cross section as shown so as to produce as it were a trumpet mouth.

A ring of fibre 9 is screwed on the boss 7, at its outer end, such ring 9 being insulated from the boss by a ring of rubber 10 which is interposed between the facing surfaces.

The fibre ring 9 is of somewhat less on ternal'diameter and of somewhat greater iiiternal diameter than the corresponding diameters of the boss 7, and issecured on'the boss 7, concentrically therewith.

slipped on to the fibrering 9 so that its outer surface is flush with'the outer surface of the boss 7 and rubber ring 10, and'an inner metal ring 12, preferably aluminiumis fitted in the fibre ring 9, the bores of the rubber and inner rings lOand 12 forming a continuation of the bore 8 of the boss 7 but with parallel walls. i

The various rings may be secured in position in any suitable manner for example by frictional engagement: alone or by screws,

The casing 1 has secured on its circumference a bifurcated bracket 13 to receive the fulcrum pin 14 for the stylus bar 15, which is secured to the diaphragm 5 in the usual manner at one end and is bent and enlarged somewhat at the other end, as shown at 16 which is to be pivoted in the bracket 13.

In order to prevent direct metallic contact between the stylus bar 15 and its fulcrum pin bifurcated bracket 13 to receive the fulcrum pin 1e, are fitted with fibre bushes 17 and the aperture in the stylus bar 15 through 14 the apertures provided in the fulcrum pin 14, is passed through the limbs of the inverted U-shaped insulator 19.

The stylus bar '15 is provided at its free end with a socket 20 to receive the needle,

such socket 20 having a set screw 21 for clamping the needle in position.

'The circumferentially reduced end of the casing is adapted to receive a hollow cap 22 constructed of wood, the edge of the cap 22 bearing against the shoulder 2 formed on the casing 1 by reducing the diameter thereof as! hereinbefore" described. a

The cap 22 is reduced in diameter inter nally for ashort distance inwardly to form a rabbeted joint 23, and is provided with an aperture 24: in its wall, to allow the stylus bar 15 to pass therethrough.

In order to enable thesound box to be connected to the tone arm, which is of the well. known form and therefore does not require to be described or' shown, two studs 25 are secured indiametrically opposite positions,

-- on thering 11, forengagement in the usual slotsin the tone arm. v

These studs 25 as shown more clearly in Figure 3 consist of short lengths of tube surrounding screws 26 which pass through the ring 11 into the fibre ring9.

Alternatively: and as illustrated by Figure, 5 the fibre ring 9 may have formed therein in diametrically opposed positions two cavities 27 in which. are arranged springs28 adapted to bear on balls 29 fitted in sockets 30 formed inthe; ring 11, the sockets being such as to permit the balls to be projected outwardly by the springs beyond the peripheryof thering 11 but to prevent them passing entirely through the ring 11;

The balls 29 are adapted in the connected position of the sound box andtone arm to engage in sockets in the form of apertures 31 in the wall of acircular casing 32 provided at the end of a tone arm 33, which is here shown broken away as the only unusual feature is the addition of the'casing 32. This'45 casing 32 is provided internally with a circumferential groove 34 which connects the apertures 31. A

By means of this connection the sound box can be rotated or swung round relatively to the casing 32, to facilitate insertion of the usual playing needle,- in its socket 20, the v balls 29 being pressed inwardly against the action of their springs 28, and running in the groove 34, When the needle has been inserted in its socket20, "the sound box is rotated in the opposite direction, the balls 29 again running in the groove 34 until they is of increased volume, and is practically 2 free from the undesirable hissing andother surface noises incidental to talking machines,

I clalmz A sound box fortalking machines having a bifurcated stylus bar bracket, a fulcrum pin mounted in the respective arms of the bracket, a stylusbar mounted on the pin be tween the arms of the bracket, a strip mounted on the pin on oppositesides of the'stylus bar mounting and serving to maintain said stylus bar mounting in a predetermined position longitudinally of the p-inand spaced from the arms of the bracket, and an insulating section arranged between the pin and 1 the stylus bar moiuiting, I,

In testimony whereof I have signed my name to this specification. e

F ALBERT HARDY- GAY. i

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