US1065212A - Phonograph-reproducer. - Google Patents

Description

A. L. BURKE. FEONOGRAPH REPRODUOER. APPLIOATION'IILED APBA, 1913.

[/1 09/7 for: .flfimiam Z. 3 1/346 Patented June 17, 1913.

ABRAHAM L. BURKE, or CHICAGO, ILL

INOIS, ASSIGNOR TO WALTER A. SCOTT,

TRUSTEE.

PHON-O GRAPH-REPRODUCER.

Specification of Letters Patent.

Patented June 17, 1 913.

Application filed April 4, 1913. Serial No. 758,827.

To a]! whom, 2'25 may concern 'Be it known that I, ABRAHAM L. BURKE, a citizen of the United States, residing at Chicago, in the county of (look and State of Illinois, have invented certain new and useful Improvements in Phonograph-Iteproducers, of which the following is a specification.

The object of my invention is to improve the construction of phonograph reproducers in such manner as to make the reproduced sound more pleasing and a more faithful reproduction of the original sound.

As is well known the reproduction of sounds by phonographs is ordinarily made up in part of extraneous sounds not forming part of the original sounds recorded upon the phonograph record, and all sounds are not reproduced with the same proportionate value which they have in the original. These extraneous sounds may arise from a variety ofcauses, but in all cases they have an injurious effect upon the faithfulness of the reproduction and they are invariably of a disagreeable character. I have found that these extraneous sounds can be largely eliminated and the tone of the reproduced sounds greatly improved by the construction herein described and claimed and illustrated in the drawings, in which Figure 1 is a cross sectional view of a phonograph reproducer of a type now in common use, but having my improvements applied thereto. Fig. 2 is a view of the reproducer box from the side'on which the needle arm is located. Fig. 3 is a detail perspective View of my improved reproducer arm; and Fig. 4 is a cross sectional view through the end of the rcproducer arm adjacent the needlesocket. Fig. 5 is a bottom plan view of the sound box.

In phonograph reproducers, as ordinarily constructed, the needle arm is an all-metal member extending from the point of attachment to the diaphragm to the point of attachment to the reproducer needle. Ac-

cording to my invention I break the allmetal path between the diaphragm and the needle by the interposition in said path of some substance ditlerent from the metal of which the needle arms have heretofore been formed, the object being to provide a construction of such a character as to eliminate the obnoxious sounds produced by an allmetal needle arm and to improve the tone of the reproduced sound. A convenient means of bringing about the desired result is to construct the needle arm of the form shown in the drawings. The outer end 1 of the needle arm there .shown is formed of metal secured to thediaphragm 2 by means of a screw 3 in the usual manner, the end of the needle arm and the screw being further held to the diaphragm by means of wax or other adhesive 4. The outer metallic end 1 of the needle arm does not extend continuously to the inner end thereof, but is secured to an intermediate part 5 of some other material, the intermediate part 5 being in turn secured to the inner metallic part 6 of the needle arm. In practice, I have found celluloid to be a material well adapted to eliminate the undesirable vibrations and to correctly reproduce the sounds. In the form of my invention shown in the drawings, I interpose celluloid between the diaphragm and the needle. A convenient mode of assembling the structure, a mode which I have used in practice, consists in constructing the intermediate part of the needle arm of two layers 5'", 5" of celluloid, the thicker part 5 being grooved at its opposite ends to receive the outer and inner metallic parts 1 and 6 of the needle arm after which the thinner celluloid layer 5 is secured to the part 5' and the metallic outer and inner parts 1* and 6 of the needle arm are firmly secured in place by means of rivets 7 passing therethrough and through the celluloid.

My invention is in nowise restricted to the specific construction described, although I have found such'construction well adapted to the purpose intended.

Together with my improved needle arm I use certain other improvements which coact therewith in improving the quality of the reproduced sound. Beneaththe heads of the screws 8, whereby the needle arm'is secured against its knife edge bearings 9, I insert Washers 10 formed of rubber or other more or less soft and yielding material, these washers having the effect of preventing the transmission of vibration from the needle arm to the casing of the diaphragm.

A further improvmnent which I find to have a beneficial effect in connection with the other improvements herein described is the use of hard celluloid gaskets 12 between ,7

thereby obviates the injurious effect upon 1 the tones which I have found to be caused by the soft rubber gaskets. able that the improvement in by the use of the hard celluloid gaskets may be due to their having the effect of doing 1 away with the dampening of the vibrations in the diaphragm by thecontact therewith of the soft rubber gaskets, and it seems probable that the hard celluloid gaskets which directly contact with the diaphragm do not lessen its effective diameter, as is done by the direct contact of soft rubber gaskets. However this may be I have found in prac tice that a material improvement in tone is brought about by the use of the hard celluloid gaskets, and that the use in eo1nbi nation of my improved needle arm, the hard celluloid gaskets, and the washers beneath the heads of the screws, which hold the needle arm in place brings about a great improvement in the tone of phonographs, in

It seems probtone caused 1 iparts of metal and of celluloid, through some cases imparting a pleasing and true 5 tone to phonographs which without my 1m- Lprovements give only an unpleasant and lunfaithful reproduction of the original sound.

I claim:

1. In a phonograph, a diaphragm, and a needle arm,

which the vibrations are transmitted.

2. In a phonograph, a diaphragm, a needle arm, said needle arm comprising a metallic outer part secured to said diaphragm, a celluloid mtermedlate part secured to said outer part, and a metallic inner part secured to said intermediate part.

3. In a phonograph, a dlaphragm, and a needle arm, said needle arm comprising a celluloid portion through which the vibrations are transmitted.

In testimony whereof, I have subscribed ABRAHAM L. BURKE.

my name.

said needle arm comprlslng

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