US1097989A - Phonograph. - Google Patents

Description

A. N. PIERMAN.

PHONOGRAPH. APPLICATION FILED DBO. 20. 1907.

1,097,989. Patented May 26, 1914.

PATENT OFFICE.

NEW JERSEY, ASSIGNOR TO NEW JERSEY WEST ORANGE, NEW

JERSEY, A CORPORATION OF NEW PHONOGIRAPH.

Specification of LettcrfiDPatent. Application filed December 20, 1907,

Patented May 26, 1914. Serial No. 407,277.

To all whom it may concern Be it known that I, ALEXANDER N. PiER- MAN, a citizen of the United States, and a resident of Newark, in the county of Essex and State of New Jersey, have inventedcertain new and useful Improvements in Phonographs, of which the following is a description. 4

My invention relates to phonographs and allied talking machines and particularly to improvements in the lever which carries the reproducer ball or point. In the reproduction of sounds by means of a phonograph it is of the utmost importance that the vibrations imparted to the stylus in its travel over the minute undulations of the record surface be faithfully transmitted to the diaphragm without any change whatever due to foreign causes, such, for example, as lost motion. Since the extreme width of the record groove in the standard phonograph record cylinder is not over one one-hundredth of an inch and 'it does not exced in depth one one-thousandth of an inch, it is evident that the slightest lost motion will affect very seriously the reproduction of sound, and this is the more true because it is the practice in instruments of this type to amplify the vibrations of the stylus which are imparted to the diaphragm which results also in multiplying any lost motion which may be present. This amplification is usually accomplished by mounting the reproducing ball or pointon the shorter arm of a pivoted lever the opposite and longer arm whereof is connected to the diaphragm. In this art the reproducing ball or point is often termed the reproducing stylus, and for convenience of reference the lever carrying the same is hereinafter called lever.

It is the object of this invention to prothe stylus vide a stylus lever for the phonograph so constructed that all possibilityof lost motion due to the pivoting of the said lever in its support shall be overcome.

In order that my invention may be fully understood, attention is directed to the accompanying drawing wherein the same reference numerals are applied uniformly to the same parts, and in which- Figure l is a view in side elevation of a phonograph reproducer equipped with my improvement, and Figs. 2, 3 and at are sectional detail views, Fig. 2 being taken on the line 22 of Fig. 3, and Fig. 3 being i taken on the line 8-3 of Fig. 2.

J The body of the reproducer is represented I at and the neck thereof at 2. The floating weight 3 is pivoted to the reproducer body at 4, and to this weight the stylus lever 5 is 'pivoted by means of the pivot pin 6 passing I through the stylus lever and the lugs 7 and 8 extending downwardly from the floating weight 3, the threaded shoulder 9 of the pivot pin fitting within the screw threaded l opening within the lug 7 The stylus lever 5 carries the reproducing point or stylus 10 near one end and on the under side thereof and its opposite endis connected to the diaphragm by the link 11. As the diaphragm is subjected to downward tension and flexure i because of the downward pull of the floating weight, when the device is being used for the reproduction of sound, and the diaphragm I is caused to vibrate only by changes in the nate upward thrusts and downward pulls, it is only necessary to secure the link 11 in the stylus lever 5 so that it is incapable of up ward movement relative thereto. \Vhen the link 11 is passed through a horizontal opening in the stylus lever and its lower end bent into the form of a hook or circle, as is the usual practice, a considerable amountof delicate manipulation is necessary to fasten this lever as close to the diaphragm as is desirable, and it is also difficult to shape the link so that it shall pull upward from the middle of the stylus lever and any slight bend will cause it to tend to twist the stylus lever somewhat.

In 11 y improved device a substantially cone sh ped opening is formed in the stylus lever with its smaller end directed downwardly. The link 11 is passed through this opening and a ball 12 of larger diameter than the small end of said opening is formed out-he lower end of the link. One way in which this ball may conveniently be formed is by bending the end of the link back upon itself and placing a drop of melted solder thereon, or the solder may be placed on the end of thelink without bending back the end thereof or any convenient .method of forming a ball on the end of the link maybe used. With the connect-ion made in this manner the link always pulls upward from downward pull thereon and not by alter pin 6 of a uniform' diameter throughout itslength, no special provision would be necessary'to avoid lost motion of the parts, since the openings in the styluslever 5 and the lug 8 could each be made of the samediameter as the pivot pin, and the close fit of all the parts would thusbe assured and all lost motion would be avoided, but it is found impracticable to make these pivot pins inlarge quantities so that they shall be of uniform diameter throughout their length. The present practice is to form such pins from a long red, the end of the rod being allowed to protrude from a chuck to an extent equal to the length of the finished pin. This chuck and the rod. held therein are rotated and by means of various tools acting upon the retating rod, the pin is cut to size, threaded and finally cut oil from the end of the rod, after which the rod is pushed out from .the

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chuck a distance equal to the length of another pin and this operation is repeated in definitely.

The parts of the phonograph reproducerare quite small and delicate and the diameter of this pivot pin is therefore necessarily very small, it being in fact in the neighborhood of twenty-five one-thousandths of an inch, and, as the pin has a length of several times its diameter, when the cutting toolis brought up to one side of the rotating rod to cut the same down to the size of the finished pin, the outer end thereof will be pushed to one side and as a result the diameter of the pin at or near its end is greater than it is at the center or near its head. As a result of the pin being made in this'way, .when the opening in the stylus lever is formed sufiiciently large to permit the patsage of the pin therethrough, as is necessary in order to assemble the parts, and the lever is placed in the position upointhe pin which it finally occupies, as shown in Fig. 3 of the drawing, a looseness of fit is produced which.

may amount to two or three thousandths of an inch (see Fig. l), and thereby lost motion is caused in the turning of the leverupon the pivot pin. In order to obviate-. thisdiin'culty and to do away entirely with, all lost motion of the stylus lever upon the pivot )ill, I lever-only as-large as the smallest part oi the pivot pin or slightly smaller than this size, and I'then cut a slot or kerf 14 in the material of the stylus lever, which slot comrnunicates with the opening 13 in the said form the opening in the said stylus lever. Thd slot or kerf 14 is shown in the drawings as having been cut inwardly from the peripheryof the stylus and intersecting and passing beyond the opening 13, but it is obvious that this slot or kerf need not ex tend to the periphery of the lever and it need not extend beyond the opening at both sides thereof, it being important only that it shall communicate with the openin in order that by separating the walls 0 the slot or forcing them nearer one another, the size of the opening 13 may be increased or diminished. I also form the pivot pin 6 with a slight bevel at its outer end. The parts being thus constructed may be readily assembled by pushing the pivot p 1 6 forcibly into place and screwing it into the lug 7 As the stylus lever isformed of resilient material, preferably ofi'steel or brass, the walls of the kerf 14 which are spread apart by the passage of the enlarged end of the pin 6 through the opening 13, will spring together again, and the central portion of the pin, which is of reduced diameter, will fit closely within the opening in the stylus lever. If it is found that the fit of these parts is too tight, and as a result the stylus lever does not readily turn upon the pivot pin, the grip of the lever upon the pin may be reduced by prying the walls of the slot or kerf therein slightly apart, or, if the fit of the parts be found to be too loose, the size of the opening may be reduced, as for example, by pressing the walls of the kerf or slot together with a pair of pliers. By the use of the slotted stylus lever constructed as above described I am enabled to adjust the size of the opening in the stylus lever to fit the pivot pin .and thereby avoid all lost motion between the lever and the pin. 1

Having now described my mvention,what I claim 1s:

1. In a reproducer, the combination of vibratory means, a stylus lever having at one end thereof a conical opening, the smaller end of said opening being directed away from said vibratory means, and means passing through said opening for connecting said lever to said vibratory means, substantially as described.

2. In a phonograph reproducer, the combination of a diaphragm, a body in which said'diaphragm is fixed, a floating weight pivoted to said body, a stylus lever having a cone shaped opening near one end thereof,

a stylus on said lever, a link connected to.

said diaphragm and passingthrough the said opening and having a ball on its lower end, substantially as set forth."

3. In a phonograph reproducer, the come bination of a diaphragm, a body in which said diaphragm 18 secured, a stylus lever pivotally supported adjacent thereto, said lever carrying a stylus-at one end and being provided with an opening in a vertical plane combination of a pivot lever mounted on said pivot pin therefor having a tapered end, a'

central portion reduced with respect to said end and supporting said lever, and a threaded shoulder at its opposite end, and means provided with a threaded portion engaging said shoulder for supporting said pivot pin,

substantially as set forth;

5. In a device of the class described, the

combination of a pivot pin, and a stylus lever mounted on said pin and adapted to oscillate on the same, said lever having an opening for said pin and resiliently connected portions on opposite sides of said opening tosnugly incase said pin within said opening, substantially as described. V 6. In a device of the class described, the )in, and a stylus pin and adapted to oscillate .on the same, said lever having an opening for said pin and a slot or kerf communicating with said opening, substantially as described.

7. In a device of the class described, the combination of a pivot pin, and a stylus lever mounted on said pin and adapted to oscillate on the same, said lever having an opening for said pin and a slot or kerf-communicating with said opening and extend-- ing to the periphery of the lever, substantially as described.

8. In a device of the class described, the combination of a pivot bin, and a stylus lever mounted on said pin and adapted to oscillate on the same, said lever having an opening for said pin and a slot or kerf communicating with said opening and extending on 01)- posite sides thereof, substantially as described. I 4 9. A stylus lever for sound reproducers having a conical opening adjacent one end thereof and a stylus adjacent the other end thereof, said stylus being positioned on the under side of said lever and the smaller end of said opening being downwardly directed, substantially as described.

10. In a phonograph reproducer, thecombination of a diaphragm, a support therefor, a stylus lever, a stylus at one end and provided with an inverted cone shaped opening near the other end thereof, and a link connected to said diaphragm, passing through said opening, and having a ball below said opening of larger diameter than the bottom of said opening, substantially as described.

This specification signed and witnessed this 17th day of December,1907.

ALEXANDER N. PIERMAN.

Witnesses FRANK D. Lnwis, CHARLES F. RoBsoN.

cents each, by addressing the Commissioner 0! Patents,

Washington, D. G.

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