US9559A - Frame of pianofortes - Google Patents

Description

UNITED STATES PATENT OFFICE.

J. PIEFAUT, OF NEXV ORLEANS, LOUISIANA.

FRAME OF PIANOFORTES.

Specification of Letters Patent No. 9,559, dated. January 25, 1853.

T0 all whom it may concern:

Be it known that I, J. PIFFAUT, of New Orleans, in the parish of Orleans and State of Louisiana, have invented certain new and useful Improvements in Pianofortes; and I do hereby declare the following to be a. full, clear, and exact description of the same, reference being had to the accompanying' drawings, marked, respectively, Nos. l, 2, 3, 4, and 5, and of which- No. l represents a top view of the frame, No. 2 represents a view from the underside, No. 3 represents a section through the red lines of Nos. l and 2. No. 4 represents an enlarged view of the movable part of .the frame, and No. 5 the same in outline and thn parts detached.

Similar letters and numerals in the several drawings denote the same parts.

The nature of my invention consists in so constructing the metallic frames of pianoiortes, as that the inside frame or that which supports the long bridge of the piano, may be raised or lowered at pleasure, and thus raise or lower the tone of the instrument, and at the same time keep up the general accord of the piano.

To enable others skilled in the art to make and use my invention, I will proceed to describe the same with reference to the drawings.

The frame is made entirely of iron or other metal, and may be cast in one piece, and of such form and size as may be found essential. The movable or adjustable part A, which supports what is termed the straight or long bridge;7 of the piano is connected to the frame as seen in the drawing Nos. 3 and t, where a, represents the bridge, and o, c, c, the pins to which the strings or wires are attached. In the rear end of this movable part A, is a screw N, which has a square stem X, for receiving a similarly shaped pod on the key X, which is designed for turning it. It is evident that by running down the screw N, the rear end of the part A, will be drawn down, while the Jfront part which carries the bridge will rise in a corresponding` degree, thus raising the tone ot the piano, which may be lowered again at pleasure by a reversed operation.

To raise or lower the tone of an instrument, and still preserve its accord, it is well known that, the coarser strings will require more straining than the finer ones, so that as this operation is a constantly varying one, which no rigid or nonadjustable apparatus could provide for, some allowance must be made for it. For this purpose I arrange besides the center screw N, one on each side of it and near the ends of the frame (O, 13,) which are similarly connected to the main frame, in all respects as that at N. These screws are provided respectively with curved levers N', O', P', to which they are permanently fixed, so that by the turning of one the other will move with it. These levers are connected together by connecting bars R, R, which are attached by screw bolts passing through slots in the levers, in which they are made adjustable, so as to make the coarser strings when the tone of the instrument is to be raised undergo a greater degree of tension, than the iner ones, which may be done by increasing the length of the lever by means of its slot, (and vice versa) and thus preserve the accord. By turning the screw N, motion is given through the levers and connecting bars, to the screws O, I), and consequently all three act simultaneiusly, vand with that degree for which they may be set.

B, represents a dial or indicator, upon which a hand on the screw P, marks the degree to which the instrument is raised or lowered.

C, represents pieces of wood with which the metallic movable part A, may be filled, so as to better hold the pins c, 0 c which extend into them.

F, represents the crooked bridge which is fixed to the trame, in the ordinary well known manner. The number of ribs g may be increased or diminished, or so arranged as best to support or counteract the strain upon the wires.

The movable part A, has two motions independent of the frame-viz: one horizontal, or so that, while the bridges cannot appro-ach each other nearer than a given point, they may be moved or recede one from the other-the other motion is in the arc of a circle upward for straining up the wires. I have described the long bridge only as being adjustable-the other may be made so, but this I consider as fully embodied in the principle which I claim.

Having thus fully deseribed my invention What I Claim therein as new and desire to secure by Letters Patent is- In combination with the metallic frame of 5 a pianoforte, the movable part Which supports the bridge, and which is raised or lowered at pleasure by means of a key operating through the screws and levers, or their equivalents, for the purpose of raising or lowering 'the tone of the instrument, and at 10 the same time preserving its accord, substantially as described.

J. PIFFAUT.

1Witnesses Q. A. DE SEMLES, A. B. STOUGi-ITON.

Images