US2138669A - Tone deflector for grand pianos - Google Patents

Description

TONE DEFLECTOR FOR GRAND PIANOS /Mflh Patented Nov. 29, 1938 UNITED STATES PATENT OFFICE Herschel E. Tower, Cincinnati, Ohio, assignor to The Baldwin Company, Cincinnati, Ohio Application October 3,

5 Claims.

When a grand piano is placed in a room over a carpet, the tone waves from the under side of the soundboard are directed against the carpet, resulting in a damping effect, owing to the absorption of sound by the carpet material. The present invention overcomes such a defect by deecting the tone waves from the under side of the board to each side of the piano, by employment of a number of vanes of sounding board material. The use of a number of vanes assists additionally in such deflection by the reflections taking place from any one Vane to the adjoining vanes.

In the drawing:

Fig. l is a View of a grand piano from above, with the plate and soundboard removed, so as to show the construction and placement of my Vanes in an exemplary embodiment.

Fig. 2 is a cross-section of a grand piano taken lengthwise, and showing the relationship of my Varies to the soundboard and strings.

Fig. 3 is an end View of two vane structures in relative positions and as if viewed from the front of the grand piano.

Fig. 4 is a detail of a deiiector vane.

A piano case I has a front'rail structure 2. A soundboard 3 is glued to the structure 2 and the inner rim 4 of the case I. A plate 6 is fastened to the inner rim of the case I, as at l. A number of strings 8 are stretched on the plate 6 and actuated by hammers 9, as is usual in piano construction. These strings pass over a bridge or bridges I8; and the vibrations of the strings when struck by the hammers 9 are thus imparted to the soundboard 3, also as is usual in piano construction.

A supporting post I0 is attached to the case I and extends from the front rail structure 2 to a point in the rear part of the case I, where it is attached to the inner rim 4 as indicated at 5, in Figure 1. Supported in the piano case I, adjacent to the under side of the soundboard 3 and in the spaces between the post I0 and the sides of the casev I, are two sets of vane structures II and I2. Each of the structures II and I2 contains a number of vanes I3 of sounding board material, attached as shown, to end pieces I4 and I6 and I5 and I'I. The vanes I3 extend lengthwise in a direction parallel to the lengthwise direction of the post ID and; in the direction of their widths extend downwardly and outwardly toward the sides 0f the case I.

As can be readily understood, by the use of the vane structures described, tone waves from the under side of the soundboard are diverted 1936, Serial No.v 103,885

from a downward direction to a direction having a horizontal component Such diversion has an advantage whether or not carpeting material be on the floor under the piano, since, as the result, the waves strike the floor at such angles as to be reflected outwardly.

Many modifications can be made in my invention. I have shown in the above that the tone waves are deflected to both sides of the piano. As one modification, the vanes can be placed at such angles as to deiiect the waves to one side only, say the curved or right hand side. Other modifications can be made to fit various post structures.

What I claim as my invention is:

1. In a grand piano a case having a rim, a rail extending across said rim at the forward end thereof, a soundboard resting on said rim and said rail, and tone deflectors in said case bel-ow said soundboard, said deflectors being flat panellike structures of sound reflecting material and of elongated shape, said deflectors being located substantially horizontally as respects their length but being tilted at an angle to the horizontal widthwise and fixed in such a position as to deflect outwardly sound waves emanating downwardly from said soundboard.

2. In a grand piano a case having a rim, a rail extending across said rim at the forward end thereof, a soundboard resting on said rim and said rail, and tone deflectors in said case below said soundboard, said deiiectors being flat panellike structures of sound reflecting material and of elongated shape, said deectors being located substantially horizontally as respects their length but being tilted at an angle to the horizontal widthwise and fixed in such a position as to deflect outwardly sound wavesv emanating downwardly from said soundboard, said tone deflectors extending in the direction of the length of said piano whereby said sound waves are deflected outwardly sidewise as respects the length of said piano.

3. In a grand piano having a case, a rim within said case, a rail extending across said rim at the forward end thereof and a brace extending between the rear portion of said rim and said rail, a soundboard resting on said rim and said rail, said brace being located below said soundboard, and a. plurality of tone deiiecting means extending in the general length of said piano and lying in the same general plane as said brace and on either side thereof, said tone deflecting means comprising panel-like structures of sound reflecting material interspaced from each other and supported at their respective ends, said tone deecting means being substantially horizontal in the direction of their length but tilted widthwise at an angle to the horizontal and xed at an angle to deflect outwardly sound waves emanating downwardly from said soundboard.

4. A structure as claimed in claim 3 wherein the tone deecting means on opposite sides of said brace have an opposite angularity widthwise, whereby to reflect sound Waves outwardly with respect to both sides of said piano.

5. In combination with a grand piano having a case, a rim within said case, a rail extending across the front portion of said rim and a soundboard resting on said rim and rail, at least one Widthwise and xed at such an angle to the horizontal as to deflect outwardly sound waves emanating downwardly from said soundboard when said structure is in place in said piano beneath said soundboard.

HERSCHEL E. TOWER.

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