Патент USA US2121272код для вставки
W“: EL 13. L‘ E, TURNER ' METHOD OF PRODUCING souun REPRODUCING NEEDLES Filed Jan. 28,1935 2,123,272 ' ‘ Patented June 21, 1938 2,121,272 UNITED, STATES PATENT OFFICE 2,121,272 METHOD OF PRODUCING SOUND REPRO DUCLNG NEEDLES Application Louis January E. Turner, 28, 1935, Chicago, Serial No. 3,709 1 Claim. (Cl. 29-1695) The invention relates to the production of nee In manufacturing the needle the tip of wear dles for reproducing sound. . resisting metal is first fused to the shank of It has heretofore been common to unite a tip softer metal by an electric or gas weld.‘ During of hard wear-resisting alloy, such as iridium, os this fusing the soft metal in the shank loses its 5 miridium or carboloy to a cylindrical shank of temper. Next, the tip and tapered end of the 5 softer metal, such as brass or ‘bronze, by means shank are ground on'lathes, laps or fine stones of an electric or acetylene weld but, on account. to the desired anglenecessary to ?t the record of the lack of rigidity in the shank, the sound grooves perfectly. Next, the point of the tip is reproduction was not as efficient as desired. In rounded off to secure the necessary radius by 10 some instances the tip and a portion of the shank means of tumbling in a suitable tumbler or with above the tip or a portion of the shank above the a mixture of shot and abrasives or by means of portion fused to the tip have been ?attened or abrasive paper or cloth applied against the spin made elliptical, to provide a limited amount of ning tip held in a lathe or similar tool.‘ Next, ?exing in the shank in one direction and stiffen the temper of the shank, and particularly the ing in the transverse direction. In the latter tapered end portion contiguous to the tip which type, it is necessary to set the needle so that its has been destroyed in the process of welding, is ?attened portion has a definite relation to the restored by means of hammering or rolling or direction of the grooves in the records because stamping in a press or squeezing in a screw vice, if the needle was not properly set it would injure so that the metal of the shank or said contiguous the record and would not e?iciently reproduce portionlwill be tempered or densified to provide 20 sound. ' The object of the present invention is to pro-‘ ‘ vide a simple method of producing needle which comprises a round shank of soft metal and a fused the desired rigidity. By retempering the tip portion of the shank, weakness in the common or simple round type of needle, which causes'its failure, is overcome. It is not necessary to ?atten the shank above 25 wear-resisting tip and possesses the‘desired ri gidity for e?icient and accurate reproduction and >1 the tip to give it ?exibility in one direction and does not require de?nite positioning with respect rigidity in a transverse direction, but it will be to the grooves in the record being produced. understood that a portion of the shank above the This object is accomplished primarily by fus tip portion may be somewhat ?attened or ellip ing a tip of wear-resisting metal to a shank of tical, but when the shank is retempered, as set softer metal and tempering the shank, and more forth, the rigidity of the tip portion of the shank particularly that portion which is contiguous to is not maintained, so that it is not necessary to set the upper end of the tip, to give it the desired the needle in any definite relation to the grooves rigidity for correct reproduction of sound, with in the record, and the needle will be properly out requiring de?nite positioning of the needle operative for reproduction in any rotative posi relatively to the grooves in the record being re tion. produced.‘ In practice; it has been. found that The invention is not to be understood as restrict a shank which is tempered after the tip has been ed to the details set forth, since these may be fused thereto will achieve this result. modi?ed within the scope of the appended claim, 40 The invention consists in the several novel fea without departing from the spirit and scope of 40 tures hereinafter set forth and more particularly the invention. defined by claim at the conclusion hereof. Having thus described the invention, what I The drawing illustrates a needle embodying the claim as new and desire to secure by Letters Pat invention. out is: The invention is exempli?ed in a needle com That improvement in producing a needle for prising a shank with a cylindrical body portion reproducing sound which consists in fusing a tip I and a tapered or .conoidal end portion 2, and of comparatively hard wear-resisting metal to a a conoidal record-engaging tip 3 formed of hard shank of softer metal and then retempering the metal. such as carboloy, iridium, or osmiridium. entire shank after the tip has been fused thereto. 50 The shank is formed of suitable metal, such as 50 bronze, brass,‘ or steel. The tip is fused to the LOUIS E. TURNER. end of the tapered portion 2 of the shank. The shank is tempered. .