US11566A - Tuning-fork - Google Patents

Description

J. C. JINKINS. `TUNING PORK.

No. 11,566. Patented Aug. 22. 1854.

IIE'

UNITED STATES PATENT OFFICE.

JOSEPH C. JINKINS, OF BEALLSVILLE, OHIO.

TUNING-FORK.

Speceation of Letters Patent No. 11,566, dated August 22, 1854.

To @ZZ whom may concern:

Be it known that I, JOSEPH O. JINKINS, of Beallsville, in the county of Monroe and State of Ohio, have invented a new and Improved Tuning-Fork; and I do hereby declare thatthe following is a full and exact description thereof, reference being had tO the accompanying drawings, making part of this specification.

The nature of my invention consists in producing sounds Of any required pitch, by means Of a movable cross-bar inserted in the proper positions between the prongs of the fork, substantially as hereinafter set forth.

In the accompanying drawings, Figure 1, represents a tuning fork of ordinary construction, without the movable cross-bar; Figs. 2, and 3, different views of the crossbar; and Fig. 4, view of the fork, with the cross-bar inserted for use. Like letters designate corresponding parts in the several figures.

The manner of constructing the fork itself does not essentially diifer from that ordinarily followed; except that, in general, it is made larger,especially when intended for tuning piano-fortes and other instruments requiring the tones of several Octaves. The cross-bar a, is simply a stiff metallic rod, lor piece, of suitable length to lit tightly between the prongs of the fork, as shown in Fig. 4; and in order that it may be made to press with sufficient force between said prongs, I usually cause them to spring inward a little toward each other, when the cross-bar is removed, as seen in Fig. 1, so that they will require tovbe separated somewhat to insert Or adjust the cross-bar, and will then automatically retain the same. It

is best to have the ends of the cross-bar pointed, as represented in the drawings, for the purpose of more readily adjusting it in the exact position required, to produce a given sound. A thumb-piece I), may also be added to it, for convenience in handling. The manner Of tightening it in the fork by the spring of the prongs, I have described as a convenient means of attaining the end; but a tightening screw, or other equivalent devices, may be substituted, if desired.

It is obvious that, by varying the positions of the cross-bar between the prongs of the fork, any number Of different tones vmay be produced. In order to render the instrument more accurate and useful, I also generally mark the positions of the different tones and semitones within'the compass of it, upon one of the prongs of the fork, and designate them by the appropriate letters, as shown in the drawings. In Fig. 4, the cross-bar is represented as inserted at C, in the lirst octave; and if the scale is nicely determined by the maker, the sound indicated thereby will invariably be given.

Vhat I claim as my invention and desire to secure byLetters Patent, is

Producing sounds of any required pitch, with a single tuning fork, by means of a movable cross-bar inserted in the proper p0 sitions between the prongs Of the fork, substantially in the manner herein set forth.

' The above specification Of my new and improved tuning fork signed by me this sixth day of July 1854.

JOSEPH O. J INKINS.

Witnesses:

J. S. BROWN, AARON W. GEAI-IEART.

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