US3452634A - Piano sound augmentor - Google Patents

Description

July l, 1969 J. w. .Q JTMEYER PIANO SOUND AUGMENTOR Filed April '7, 1967 W /wum United States Patent 3,452,634 PIANO SOUND AUGMENTOR John W. Quitmeyer, 400 Oak St., Rochester, Mich. 49277 Filed Apr. 7, 1967, Ser. No. 629,243 Int. Cl. Gc 3/06 US. Cl. 84-194 3 Claims ABSTRACT OF THE DISCLOSURE My invention is a sound augmentor for a piano wherein a sound post is ajustably mounted on the primary soundboard of the piano, and is detachably connected by a clamp to the access panel of the piano, so that the access panel provides an auxiliary soundboard to augment or increase the sound output of the piano.

My invention relates to pianos and more particularly to the means associated therewith for producing musical tones therefrom.

In such pianos as the consoles and spinets, the soundboard area thereof is necessarily reduced because the sounding board must be made smaller to fit into the miniature case. Also, the effective soundboard area is further reduced by the heavy hard maple bridges, particularly the treble bridge, which runs diagonally from the lower left to the upper right corner of the soundboard. Thusly, the foregoing limitations in structure of such pianos results in a smaller efiective soundboard area and in much of the natural vibration of the soundboard being muted causing such smaller pianos to have a shallow tone quality in comparison with the larger pianos.

In the past devices have been proposed to increase the soundboard area of a piano, however, such devices have been directed to fastening the primary soundboard adjacent to the supplemental soundboard, or to arrangements wherein the piano cannot be serviced or strings replaced without considerable difiiculty, and for these reasons, to the best of my knowledge and belief, such devices have not been used or been successful in accomplishing the purpose for which such were intended.

It is therefore, a principal object of my invention to provide means to effectively increase the freely vibratable soundboard area of a piano Without changing the overall dimensions or appearance of the instrument and without interfering with the accessibility of the mechanism thereof for service or adjustment.

It is a further object of this invention to substitute a secondary or auxiliary, easily detachable, soundboard in the place of the conventional forward lower access panel of a conventional piano.

It is another and further object of my invention to provide a sound augmenting means for a miniature piano including forward auxiliary soundboard means which may be easily removed to service the piano and a blind catch means for connecting said auxiliary soundboard to the existing soundboard for the piano, said blind catch means simultaneously functioning as a sound post to transmit vibrations between such auxiliary soundboard and the existing soundboard.

Another object of this my invention is to provide a magnetic latch means for connecting a forward auxiliary soundboard internally to the rearward primary soundboard of a piano.

It is to be understood that my invention possess other and further advantageous features, some of which, with the foregoing, will be set forth at length in the following ,description where that form of the invention which has been selected for illustration in the drawing accompanying and forming part of the present specification is out 3,452,634 Patented July 1, 1969 may be embodied in a plurality of forms.

Referring, now, to the drawing hereof:

FIGURE 1 is a sectional side elevational view of a spinet piano showing the conventional features thereof and the application of my invention thereto.

FIGURE 2 is a front cut-away view of the forward portion of the sound augmenting means taken along line 2-2 of FIGURE 1.

FIGURE 3 is an elevational view of the auxiliary soundboard taken along line 3-3 of FIGURE 1. 7

FIGURE 4 is an enlarged view of the blind catch means for securing said auxiliary soundboard means to the sound post means and the primary soundboard taken along line 4-4 of FIGURE 1.

FIGURE 5 is a cross sectional view of the structure of the sound post taken along line 5-5 of FIGURE 1.

As indicated by the foregoing, my invention, designated in general by the numeral 10, is shown incorporated in an upright piano of the spinet type. The casing 11 of said piano encompasses the mechanism of the piano, the conventional parts of which comprise in part, a primary soundboard 12, a metal plate 13 for supporting the strings 14 when they are tuned. Said metal strings 14 are connected to a peg or pegs 15 located at the bottom of said plate, strung over a bridge or bridges 16, and fastened to a tuning pin or pins 17 at the top of said plate. The piano 10 is further provided with a key bed 18, and a drop action 19 with reversed abstract 19a commonly provided in such spinet pianos causing the reduced soundboard area.

Forwardly of said drop action mechanism 19 and below said key bed an access opening 20 is provided in such conventional pianos for required access to the mechanism of the piano for servicing same. Said access opening is generally rectangular in outline and is provided with walls 21 formed by said casing 11 to receive a cover panel (not shown) to close off said opening 20 when same is not being used. The bottom edge 21: of said opening is provided with pins 23 for securing the cover panel at its bottom edge, and a spring clip 22 is provided at the top edge 24 of said access opening to snap fasten the cover panel into said access opening.

In accordance with my invention, I glued a wood block 25 to the back of the primary soundboard 12 at a predetermined spot 26 where the sound post means 27 is to be attached, generally centrally located with respect to said access opening. Directly in front of said spot, I drilled a /2 inch hole or bore 28 through said plate '13. I then inserted a inch metal rod 29 having threaded ends 30 between adjacent strings 14, through said bore 28 in said plate and threaded one end of said rod through said soundboard 12 into said block thereby firmly anchoring same to said primary soundboard. Next, I threaded a wooden dowel 31 of suitable diameter 32 and predetermined length 33 onto the other end of said threaded rod 29. A pot magnet catch 34 is now attached to the free, unsupported end 35 of said dowel by means of a wood screw 36 entering an opening 37 in the center of said magnet. I now provide, further, an auxiliary soundboard 38 comprising a' thin wooden board or panel 39 of generally rectangular outline mounted rigidly on a likewise rectangular frame 40 which extends around and adjacent to the edges 41 of said panel 39. Said panel 39 is of thin cross-section so that some will vibrate in response to vibrations transmitted to it through said sound post means 27 as will become apparent from later disclosures herein. A reinforcing rib 42 extends longitudinally and horizontally across said auxiliary soundboard substantially midway between the bottom edge 43 and the top edge 44 thereof, and a flat metal latch plate 45 is secured centrally to the face 46 of said rib by means of screws 47. Said pot magnet catch is adjusted forwardly by rotating said dowel until said magnet joins forcibly with said latch plate when said auxiliary soundboard is mounted in said access opening 20.

It is now apparent and understood that the auxiliary soundboard 38 may be installed and removed in exactly the same manner as the original panel, because a slight pull exerted forwardly upon the upper portion 48 of said auxiliary soundboard releases said magnet catch from said metal latch plate and said spring clip 22 disconnecting said sound post means and allowing said auxiliary 1 soundboard to be removed from said access opening for service on the inner mechanism of the piano. It is also apparent and understood that with said auxiliary soundboard in place and said sound post means integrally connected thereto and to said primary soundboard, sound vibrations induced to said primary soundboard from the keys 49 through said drop action to said strings are transmitted through the metal rod 29, the dowel 31, the magnet catch 34, the metal plate or latch 45, the reinforcing rib 42, to the wooden board or panel 39, causing said panel 25 39 to vibrate in unison with said primary soundboard and increasing the exposed freely vibratable soundboard area of the piano 10 and thereby greatly improving the tone thereof.

Having now fully shown and described my invention,

said soundboard; walls defining a generally rectangular vertical access opening positioned below said key bed and spaced a substantial distance forwardly of said strings;

an improved sound augmenting device for increasing the freely vibrating soundboard area of said piano comprising;

an auxiliary soundboard'panel of generally thin, flat,

rectangular outline, detachably mounted in and generally matching said access opening;

a rearwardly positioned elongated cantilevered sound post element having an adjustment portion fixedly fastened to said primary soundboard for extending said sound post forwardly between said strings with free end thereof terminating adjacent the rearward side of said soundboard panel;

and a blind catch member detachably connecting said rearward side of said auxiliary soundboard panel and said free end of said sound post in fixed relationship to each other when said panel is mounted in said access opening so that said blind catch member and said sound post element function together simultaneously as a unitary sound post to transmit vibrations between said auxiliary soundboard and said primary soundboard, said blind catch member operable to readily release said sound post when said auxiliary panel is moved forwardly and outwardly from said access opening.

2. In combination with a piano having a casing, a primary soundboard vertically mounted in said casing, a plate mounted in said casing adjacent said primary soundboard having walls defining openings therein, a set of strings mounted upon said plate tuned respectively to the sounds of a musical scale; at least two bridges extending between said plate walls, the bottom of said bridge mounted on said primary'soundboard and the top of said bridge supporting strings to transmit vibrations from said strings to said primary soundboard; a key bed mounted on said casing forwardly and projecting normal to said soundboard, walls defining a generally rectangular vertical access opening positioned below said key bed and spaced a substantial distance forwardly of said strings; and improved sound augmenting device for increasing the freely vibrating soundboard area of said piano comprising, an auxiliary soundboard panel constructed of generally thin, fiat, rectangular rigid material detachably mounted in said access opening to substantially close said opening, an elongated rearward sound post element fixedly mounted to said primary soundboard cantilevered forwardly between said strings having its free end thereof terminating adjacent the rearward side of said soundboard panel and a clamping device including a latch element and a catch element connecting said rearward side of said soundboard panel and said free end of said sound post rigidly together when said soundboard panel is place into said access opening.

3. In combination with a piano having a casing, a primary soundboard vertically mounted in said casing, a metal plate mounted in said casing adjacent said primary soundboard having walls defining openings therein, a set of wire strings mounted upon said plate for tuning respectively to the sounds of a musical scale, at least two bridges extending between said plate walls, the bottom of each bridge is mounted on said primary soundboard and the top of each bridge supports said strings to transmit vibrations from said strings to said primary soundboard; an improved sound augumenting device for increasing the freely vibrating soundboard area of said piano, comprising, an auxiliary soundboard panel constructed of generally thin, flat, rectangular, rigid material and mounted parallel to said primary soundboard adjacent said strings, and magnetically responsive sound post catch means operable to interconnect said primary soundboard with said auxiliary soundboard to cause said primary soundboard and said auxiliary soundboard to vibrate in unison when said strings are activated.

References Cited UNITED STATES PATENTS 711,765 10/ 1902 Heppe 84-194 2,995,983 8/ 1961 Davis 248206 3,031,799 5/ 1962 Bradsby 248206 RICHARD B. WILKINSON, Primary Examiner.

L. W. FRANKLIN, Assistant Examiner.

U.S. Cl. X.R. 248206 a

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