US1419913A - Phonograph reproducer - Google Patents

Description

B. 5.3mm). PHON'OGRAPH REPRODUCER.

APPLICATION FILED JAN. 16. 1919.

1,419,91 3. V Patented June 20, 1922.

BURR IB. BLOOD, OF CHICAGO, ILLINOIS, ASSIGNOR, BY MESNE ASSIGNMENTS, 'lO JEWEL PHONOPARIS COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

PHONOGRAPH REPRODUCER.

specification of Letters Patent.

Patented June 20, 1922.

Application filed. January 16, 1919. Serial No. 271,377.

T 0 all Whom may concern Be it known that I, Bonn B. BLOOD, a

citizen of the United States, and a resident of Chicago, in the county of Cook and State of Illinois, have invented certain new and useful Improvementin Phonogra-ph Reproducers, of which the followingis a description, reference being had to the accompanying drawing, which forms a part of my specification.

My invention relates to sound reproducers for phonographs and has for its object the provision of a construction wherein the stylus-bar is provided with a cross-head so formed that a proper pivotal mounting of the stylus-bar on the shell or casing may be provided which enables all vibrations encountered by the stylus or needle to be thoroughly imparted to the flexible or mica dia phragm of the reproducer without, however, permitting undue or improper vibration of the stylus-bar; the construction enabling a eproduction of sounds in greater volume and without loss in the tone quality.

The object of my invention as well as its advantages will be more fully comprehended from the following detailed description of the drawing, whereini Figure 1 is a front elevation of my improved reproducer with a portion of the tone arm to which it is secured.

Figure is a side elevation of the reproducer, looking at the stylus receiving socket of the stylus-bar.

Figure 3 is a detail perspective view of the cross-head of my improved stylus-bar.

In the exemplification of my invention, the casing or shell 10 is provided with the usual inwardly disposed flange 11 whereby the usual gaskets or yielding rings and the flexible or mica diaphragm are held in place in the casing; the diaphragm being also held in place by the back 12 with a gasket or rubber ring intervening, at the marginal edge of the diaphragm.

The back is provided with a central outlet or opening provided with a tone-arm connectionor elbow as at 13 which is preferablv removably secured to the backg while the 15 is shown provided with a socketed extension or stem 17, which is disposed at the longitudinal axis of the stylus-bar, in order that the stylus or needle 18, which is removably held in the socket of the extension 17 by setscrew 19, may be coincident with the longitudinal axis of the stylus-bar as shown in Figure l.

The lugs 1 1, 1 1- are spaced apart, or in other words, the cross-head 15 of the stylusbar is of such length that the cross-head may be placed between the lugs 1 1-, 14 without contacting therewith; and in the preferred form, the length of the lugs 14;, let, or rather the width of the cross-head 15, is such, rela tive to the distance from the ends of the lugs let to the perimeter of the casing or shell, that slight play or space will be provided. intermediate of the side of the cross-head and the perimeter of the casing when the stylus-bar is in proper or operative position. The ends of the cross-head 15 are both provided with flared or bevelled sockets as at 20 in Figure 3; the sockets being preferably located coincident with the longitudinal axis of the cross-head l5 and adapted to receive the pivot forming members or pointed screws 21, 2t, which extend through the lugs let, ll,

and have threaded relation therewith.

The flared sockets 20 are of such size as to permit the ends of pivot-forming members 21 to enter the sockets and merely contact with the cross-head 15 at the points of members 21 so as to provide asensitive pivot or support for the stylus-bar.

In my improved construction, the crosshead of the stylus-bar is provided merely with the twobearing or pivotal points on the shell or casing and thus readily allow all of the stylus vibrations to be freely transmitted through the stylus-bar to the center of the flexible or mica diaphragm.

In order, however, to prevent improper play, and, therefore, undesirable vibrations between the cross-head of the stylus-bar and the pivot-forming members, it is essential that the pivot-forming members be brought into firm holding relation with the crosshead so as to prevent any movement of the latter in a direction lengthwise thereof.

At the same time, it has been found in practice that in adjusting the pivots for the stylus-bar so as to prevent lateral or sidewise movement thereof, the pivot-forming members are brought into such firm or binding relation with the cross-head that the tone quality oi? the reproducer is seriously allccter. In order, therefore, that a too rigid or still connection between the pivot forming members and cross-head of the stylus-a may not be possible, I provide, in the particular exemplification, a slot 22 dieposed transversely of the cross-head 15, extending from one of the longitudinal sides thereof to a point somewhat beyond the longitudinal axis of the cross-head, or rather to a point beyond the plane in which the pivot-forming members 21 are disposed. The Slot- 22 extends entirely through the cross-head from front to rear thereof and terminates at a point slightly removed from one of the longitudinal sides ot the crosshead so as to leave sufficient metal to firmly hold the partially dismembered portion or end of the cross-head in place.

It is evident from the construction shown and described that the slot 22 will permit the end of the cross-head. intermediate of the slot and the adjacent pivot-forming member, to yield sufliciently, when the members 21, 21 are screwed into firm contact therewith, so as to prevent a binding or non yielding relation between the pivot-forming members 21, 21, and the cross-head of the stvlus-bar.

\Vith my improved construction, a more delicate adjustment of the pivot points mav be obtained, as a result of the flexible or springy nature of the partially dismembered portion or end of the cross-head, thereby providing a yielding relation with the pivot forming members.

t the same time the yielding relation between the cross -head and pivot forming members is such that no undue vibration or chatter is possible; while at the same time the delicate vibrations encountered by the stylus or needle will be properly transmitted through the stylus-bar to the flexible or mica diaphragm of the reproducer.

T he slot 22 is, of course, formed near the end of the cross-head as shown and preferably at what may be called the lower end of the cross-head whenthe reproducer is in the position shown in Figure 1; although a similar slot might be formed at the other end of the cross-head; and certain m0difications in the general construction may be made without, however, departing from the spirit of my invention.

I have found in practice, that with my improved construction, the volume of the tones is not only greatly increased, but that clearer tones are obtained and the finer details or undertones are reproduced because of the yielding adjustment obtainable.

hat I claim is i In a phonograph reproducer, a stylus-bar provided with a cross-head and stylusholding portion at one end, the cross-head adjacent one of its ends being provided with a slot extending transversely therethrough from onelongitudinal side to a point beyond the longitudinal axis of the cross-head so as to provide a partially severed end portion adapted to yield in a direction lengthwise of the cross-head.

. BURR B. BLOOD.

lVitnesses HEIDMAN, F. A. FLORELL.

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