US2399035A - Phonograph stylus - Google Patents

Description

April 23, 1946. |MELMANN 2,399,035

PHONOGRAPH STYLUS Filed June 18, 1942 INVENI'OR.

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cases a a it cage, ml assignor Permo yrodnct Corporatiomjfihlcago, his a corporation oi ois Application June it, 1M2, Serial No. M753 This invention relates in general to phonegraph styli and more particularly to a stylus for phonograph reproduction.

. (or. cri es) grooves. since the width of the groove in conventional re'cords'varies, the resilienceprovided The problem of producing a phonograph stylus-which inherently has wear-resistant characteristics and with controlled high frequency transmission, has long been desired by the phonograph industry. Previous attempts to solve this problem resulted in the construction of phonograph styli which comprises several parts assembled .into a single unit in an eflort to obtain a predetermined vertical and lateral resilience. These multi-part styli resulted in unravorable operation largely due to symphathetic resonance and the diificulty in producing a com= posite stylus-having a relatively small mass.

In the present invention the above objections are completely overcome through the novel con-- struction of a one-piece stylus formed in a manner whereby compliance in both vertical and lateral directions, as well as its periodof sympa-- J thetic vibration, is predetermined and constitutes a principal object of the invention. A further object of the invention is the construction of a phonograph stylus having a predetermined resilient section oilse't with relation to its shank. 1

A further object of the invention is the provision of a one-piece stylus having an offset portion for carrying the reproducing point, with said ofisetportion resilient in two directions with respect to the shank.

Further objects and advantages of the invention will appear in the following description and drawing, in which:

Fig. 1 is a side elevation of the stylus.

Fig. 2 is a top plan view of the stylus shown Fig.

Figs. 3 and 4 are side and top views ofv an alternate form of construction of the stylus shown Fig. 1.

Figs. 5 and 6 are side and top'views of a second alternate form of construction 0! the stylus shown Fig. 1.

The stylus shown Fig. 1 consists of a shank member 5 adapted to be afllxed in a conventional type pick-up through the means of a chuck. An integral ofiset extension portion 2 oithe shank l joinsthe point carrying end 3 of the stylus which terminates in a conical tip having its axis substantially vertically positioned with respect to the surface of a record (not shown). This tip is usually of hard, wear-resistant metal and is welded to the end 3 at a junction 5. The thickness of the extension 2 is proportioned to by the extension 2 enables the tip 6 to readily comply with vertical movement which is usually.

of such frequency and amplitude not readily absorbed by the mass of the pick-up in which the shank of the stylus is secured. The dotted line 5 shows an outline of the displaced position of the end 3. The vertical movement oithe tip t is thus absorbed and this transient vibration'is not transmitted in the shank i and to the pick-up.

In Figs. 3 and 4, the identical result is obtained by merely flattening the ofiset portion 2A, rather than machining away the metal of the shank as shown Fig. 1. By controlling the thickness of the flattened portion 2A, the desired vertical resilience of the end 3A is obtained.

In the second alternate form shown Figs. 5 and 6, a second resilient section i3 is formed in the ofiset at right angles-to the resilient section 23 which provides for the lateral deflection of the end and tip 33 and $3. The resilience impartedby the section lB; provides for limited lateral movement of the end dB in order to all nata certain predetermined high frequenc imdulationsencountered by the tip 43,

. in record grooves, from being transmittedto the shank 1B and thence to the pick-up.

It has been found that the vertical resilience of the tips 6, @A, and 6B, in the styli described,

. with respect to their she l," HA, and IE,

provide vertical resilience of the .end 3 when the greatly minin zes the wear between. the tip and the record when in operation and through controlling the thickness of the section lB, shown Figs. 5 and 6, high frequency discrimination is afforded which-minimzes the transmission of undesirable frequencies to the shank IB, which greatly improves the quality of reproduction obtained by the pick-up. I

Having described my invention, I claim:

A phonograph stylus comprising a substantially rigid straight shank portion adapted to be secured in a pick-up, an integral ofiset extension portion extending substantially normal Y to said shank portion, said odset extension term i- 'nating in a playing portion extending substantially at right angles to said extension portion,

said playing portion having a conical tip at its end for engaging a groove in a record, said extension having a flattened portion in its length for providing predetermined vertical resilience of said playing portion with respect to said shank, a second flattened portion in said oflset extension at right angles to said first flattened portion for providing predetermined lateral resilience to said playing portion with respect to said shank.

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