US2385945A - Stylus - Google Patents

Description

1 Oct. 2, 1945. F. w. SCHMIDT STYLUS Filed Jan. 4; 1945 my E17 :7?

franc/'5 W 5060112115 Patented Oct. 2, 1945 UNITED STATES PATENT OFFICE s'rYLUs Francis W. Schmidt, Chicago, Ill. Application January 4, 1943, Serial No. 471,230

This invention relates to improvements in a stylus or needlefor association with sound reand faithful'reproduction. Needles of the type heretofore known carry considerable vibrations to the reproducer and pick-up arm, thus interfer ing with fidelity of tone in the reproduction. Again, in niost records thereare defects, such as alignment of the groove toward the center of the record, warping or other unevenness of the record face, and, the fact that the angle of contact between the needle point and the record groove changes as the needle approaches the center of the record in the case of a disk record,

and other and various defects frequently occur. In s'uchcases, there is both an upward pressure and a side pressure against the needle which causes considerablescratching and scraping and a. consequent throw of the pick-up arm vertically and horizontally, all of which adds additional and undesirable noises to the reproduction of the recorded sound. Due to variations in the record groove, jouncing of the tone arm frequently occurs, and quite often the tone arm or reproducer is accidentally dropped a short distance. so that the needle forcibly trikes the record and may permanently injure the record. 'In'addition, with 2 Claims. "(01. 27 1-48 and pick-up arm, and to merge one vibration into another in a sinuous manner with the elimination of any sudden jolts or jars or changes from one vibration to another of a difierent character, thus materially enhancing the smoothness of reproduction.

Still another object of the inventionis the provision of a record stylus so arranged as toprovide an equalized pressure to all vibrations resulting from contact of the needle point with formerly known apparatus record wear mainly results from the scratching of the needle or stylus in the groove of the record, and obviously it is desirable to prolong the record life to as great I as possible an extent.

With the foregoing in mind, it is an important object of the instant invention to provide a stylus for use in sound reproduction from records, which stylus results in greatly improved fidelity in reproduction.

Another object of the invention is the provision of stylus which considerably reduces so-called record noises in sound reproduction.

It is also an object of this invention to provide a record stylus so constructed as to absorb a portion of the vibration resulting from needle con I the record, so that the needle faithfully follows all vibrations of the record groove, and a truer and, higher quality reproduction results.

A-further object of the invention is the provision of a record stylus so constructed as to be highly shock-absorbing, so that injury to a record does not result from an accidental dropping of the tone arm or reproducer a short distance in a manner such that the pointof the needle backed by the weight of the reproducer or tone arm strikes the record. While some'of the more salient features, characteristics and advantages of the instant invention have been above pointed out, others will become apparent from the following disclosure, taken in conjunction with the accompanying drawing, in which:

Figure 1 is an enlarged side elevational view of a stylus or needle embodying. principles of this invention;

Figure 2 is a bottom plan view of the stylus in Figure 1;

Figure 3 is a bottom plan view of a stylus of somewhat different construction, also embodying principles of the instantinvention;

Figure 4 is a part sectional,- part side elevational view of the stylusshown in Figure 3;

Figure 5' .is a fragmentary elevational' view showing the stylus bfFigures. 3 and 4 mounted in operative position in a. reproducer;

Figure 6 is a front elevational view of a stylus embodying a still different construction and in- I In that illustrated embodiment invention seen in Figures 1 and 2, there is shown reproduction c orporating principles of the'instant invention;

"and

Figure '7 is a. side elevational view of the stylus of Figure 6, taken at a 90 angle to the showing in Figure 6.

As shown on the drawing:

a stylus generally indicated by numeral l which is preferably made from a single piece of mateof the instant I rial, such as a high quality steel, alloy, or other metal. The piece of material is wound in the form of a helical spring as indicated at '2, and near the lower end thereof the convolutions of the spring are gradually narrowed so that a taper 3 results leading into a sharply defined elongated point 4, the tip 'of which rides the groove of the record.

It will be noted from this construction .that

defects in the surface or groove of the record as well as excess vibrations resulting from the stylus tracking the groove will be absorbed by the flexible resilient body of the stylus and the major portion of such shocks and vibrations will not be transmitted to the reproducer. Further, it will be especially noted that vibrations resulting from the tracking of the needle willbe merged one into the other in a sinuous manner so that therewill be no abrupt jerk from the vibration of one type to that of another type, and the will consequently be much smoother; In addition, it will be seen that the reproducer and tone arm will ride much more evenly even though the needle follows every deviation in the side walls of the record groove, by virtue of the shock-absorbing powers of the needle. .Further, by virtue of these same shockabsorbing powers the pressure of the needle upon the record is equalized'and kept nearer to a constant value regardless of the deviations in the record groove because the reproducer and tone arm are held to a smooth movement and their weight is-not transmitted directly to the record surface through a stifi rigid connection. The coils of the helical spring 2 nearest the point are not in direct contact with eachother but vibrations and permit the point to move relatively to, the remainder of the spring 2. Sudden dropping of ,thetone arm or reproducer head will. not result in a permanent injury to the record, if that drop is of reasonable distance, because the sudden shock of the, point of the needle striking the record will be absorbed by the body -of the needle to a considerable extent.

length of time, and consequently the lite and usefulness of the stylus is greatly prolonged.

In Figures 3, 4 and 5 I have illustrated a stylus of somewhat different construction, but still providingall of the advantages of that'shown in Figures 1 and 2.

In this instance, the stylus is made up of a v number of initially separate pieces. The structure includes a solid shank 5 which isheaded byswaglng or an equivalent process at its lower end as indicated at B. Spaced upwardly from the head 6 a fixed collar 1 is secured-to the shank. Prior to the application of the collar 1 a resilient stylus point is, dropped over the shank torest I against the head 6. This point construction embodies a helically wound spring-like body 8 which terminates in a, projecting point 9 for contact withth record. :The body portion 8- is freely' floating around the shank 5 and may rotate relatively to the shank. A coil spring I0 is preferably mounted around the shank between the helical body 8 of the stylus point and the collar I to urge the stylus point downwardly at all times against the head 6. In order to facilitate the secure mounting of the stylus in a reproducer.

head, the shank 5 is provided with a fiat spot II in its upper portion for engagement by the trated at l5.

are spaced apart sufiiciently to'better absorb.

Likewise, record wear is reduced to a minimum v because the needle is permitted to move by virtue of its own resiliency both vertically and horizontally in keeping with the record track and relatively to the reproducer and tone arm so that the full weight of, the tone arm and reproducer head is not transmitted directly at every angle to the face of the record. Of course, during reproduction from a grooved record most of the wear will occur. on the record because. of its softer substance in comparison with the reproducing stylus. However, some wear is bound'to occur to the stylus itself. With the structure shown in Figures 1 and 2, and likewise with the structure shown in all of the other figures of the drawing. a stylus made in accordance with the instant invention will wear more evenly so that auniform point or tracking end will be retained on the stylus for a considerable Figures 1 and '2.

struction of this stylus may rotate or swing rela- The stylus seen in Figures 3, 4 and 5, as statedv above, provides all of the advantages obtained from the previously described stylus seen in In addition, the point contively toits shank 5 and thus lateral vibrations may be taken up by the stylus itself without any but a negligible throw or swing of the reproducer head and pick-uparms, so that the ultimate reproduction is smooth, even, and of great fidelity. It should be noted that the position of the stylus seen in Figure 5 is the preferable position also 'for the other illustratedembodiments of Styli, I

In Figures 6 and 7 I have illustrated still anothen form of construction for my novel stylus. In this instance, the stylus includes a shank l6 having the customary flat spot I! adjacent the 'upper end thereof for engagement by-the set screw in the reproducer head. The point construction embodies a helical wound spring body portion l8 which terminates in a sharp projection I9 for tracking in the record roove. The

'- spring wound body It is tightly affixed to the shank I6, but it will be especially noted that the shank terminates as indicated at 20 well above the lower end of the coiled bodyportlon l8 so that below the end of the shank the coils are slightly spaced apart and the needle functions in substantially the same manner as above described in connection ,with the showings in Figures 1 and 2.

In Figures 6 and 7 I have also illustrated a' construction for the point of the needle which construction may, if so desired, be used as well and in an obvious manner on the needle con- 4 illustrated the stylus con- T track properly in a record groov and not tend to ride high on the side walls of the groove in such a position that itwill not be able to follow the deeper deviations of the record groove. There will, therefore, be less wear of the side walls of the record groove, and the life of the needle is considerably prolonged.

From the foregoing, it is apparent that I have provided along lived reproducing stylus which is simple in construction, highly economical, and which greatly improves the fidelity of reproduction, as well as conserving the life of the record.

It will, of course, be understood that various details of construction may be varied through a wide range without departing from the principles of this invention and it is, therefore, not the purpose to limit the patent granted hereon otherwise than necessitated by the scope of the appended claims.

I claim as my invention:

1. A stylus for reproducing recordings from a grooved record, a stif. shank for connection to a reproducer, a helically wound body fixed to said shank, and a pointed element extending from said body to track in a record groove, said body being resilient and extending beyond the outer end of said shank, the portion of said body beyond the shank being movable relatively to the portion on the shank and the shank.

2. A stylus for reproducing recordings from a grooved record, including a rigid shank member for connection to a reproducer, an elongated body member helically wound around said shank member concentric with the axis thereof, said FRANCIS W. SCHL IHDT.

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