US794664A - Piano-plate. - Google Patents

Description

PATENTED JULY 11, 1905.

J. DAVENPORT. PIANO PLATE.

APPLICATION FILED NOV. 29, 1904.

WITNESSES.-

L. ZM.

Attorney;

UNITED STATES Patented July 11, 1905.

JOHN DAVENPORT, OF STAMFORD, CONNECTICUT.

4 PIANO-PLATE.

SPECIFICATION forming part of Letters Patent No. 794,664, dated July 11, 1905,

Application filed November 28, 1904:. Serial No. 234,517.

To whom it may concern:

Be it known that 1, JOHN DAVENPORT, a citizen of the United States, and a resident of Stamford, in the county of Fairfield and State of Connecticut, have invented certain new and useful Improvements in Piano- Plates, of which the following is a specification.

My invention relates to an improved construction of piano-plates such as is employed to support the strings in all styles of pianos.

Numerous designs of piano-plates have and are being made for the different manufacturers of pianos, which plates are all cut away more or less and are also braced in different ways; but so far as I- am aware all of these different styles of plates are mostly formed of cast metal and usually in one piece. These cast-metal plates are reinforced around their edges and through the webs of the cutaway portion to properly strengthen and brace the plate against the enormous strain applied with the tightening of the wire strings which are attached to the pins in the respective bridges. The best metals are usually employed from which to cast these plates, yet they not infrequently break after the strings are attached and as a result of the strain resulting therefrom. This, together with the excessive weight and great amount of labor required in producing and finishing these cast plates, renders them objectionable, and it is with a view of overcoming said objections and improving the tone of the piano that I have devised my improvement.

It is therefore the object of this invention to produce a piano-plate from a series of sections of rolled, drawn, or pressed sheet metal properly formed and secured together in a way to produce a lighter plate than would be practical from cast-iron, and to give greater strength through the braces and other portions where the cast plates are usually weak, and, further, to make it possible to produce a plate Whose sound-conducting properties will be greatly enhanced, and, finally, to produce a late which may be manufactured and finis ed in quantities cheaper than is possible from cast metal.

With the above and other objects in view I have devised the novel construction and combination of parts shown upon the accompanying two sheets of drawings, forming a part of this specification, upon which similar characters of reference denote like or corresponding parts throughout the several figures, and of which Figure 1 shows a front elevation of a popular design for piano-plate constructed in ac cordance with my idea. Fig. 2 is a crosssectional view taken on line 2 2 of Fig. 1. Fig. 3 is a detail side elevation of a brace employed in my construction, the same being shown as viewed from the arrow 3 in Fig. 1 and bent to accommodate the under or treble strings in the middle section. Figs. 4 and 5 are detail cross-sectional views taken on lines 4 4 and 5 5, respectively, of Fig. 1.

The main body of the plate may be formed of sheet-steel of about one-half the thickness required in cast metal and may be stamped out or sawed, as preferred, and likewise of any particular design required to meet the fancy or requirements of the numerous makers. In the stamping of these bodies the numerous holes (not shown in the drawings, but required in all piano-plates for the location of screws, tuning-pins, &c.) may also be punched, thereby saving a great amount of labor over the present drilling process.

Referring in detail to the characters of reference marked upon the drawings, A indicates the body or frame, which, as shown, is formed from a single piece of sheet metal, being cut away in the usual way to permit the sounds to pass therethrough, but having suitable Webs of varying width to reinforce the body and to accommodate the reinforcing-strips, all of which would be preferably formed of rolled, stamped, or pressed sheetsteel. thereto upper reinforcing-strips d and e, forming a border, which may be formed of halfround or other shaped steel strips, while the bottom edge is preferably provided with aflat strip j, secured in the same way.

g, h, i, and indicate tying and reinforcing braces of rolled or pressed structural steel of any preferred shape and best adapted to tie The body, as illustrated, has riveted the upper and lower portions of the plate together and to stiffen, brace, and strengthen the plate throughout. The particular design and number of these braces, as also the other attached strips, may be varied to obtain the best results and to produce plates of different designs. The brace 9 (shown in detail in Figs. 2 and 3) is shaped to form a loop 7r to accommodate the under line of strings (not shown) extending from the lower end of the hitch-pin section Z up over the upper bridge-bearing m and back-bearing n, attached to tuning-pins in the upper portion of the plate, but not shown in the drawings. The hitch-pin section is shown reinforced with sheet-metal strips of the desired shape attached thereto with a double line of rivets. The bridge and back bearing strips m and n, riveted to the upper portion of the body, would preferably be formed of rolled steel and each contain a central raised portion and obviously serve as a bearing over which strings are drawn and tightened by the tuning-pins. (Not shown, but located above.)

0 indicates the upper bass-bridge, which, like the lower bass-bridge p, is formed of structural steel of any preferred shape. These two bridges in practice each support a row of pins (not shown) to the lower row of which the bass-strings (not shown) are connected and are drawn over the upper ones to the tuning-pins. a

(1 indicates a further attached strip of rolled steel by means of which the outer edge is reinforced.

r indicates an attached steel strip to form a back-rib bearing, as shown in dotted lines in Fig. 1.

it will be obviously apparent that the various steel strips attached to the body of the plates are preferably secured by means of rivets, as indicated, and that any number of such rivets or their particular locations may be varied as the manufacturer may deem advisable.

Having thus described my invention, what I claim, and desire to secure by Letters Patent, is

1. A piano-plate formed of rolled metal and comprising a sheet-metal body having its edges, bridges and brace-sections reinforced.

2. A piano-plate formed of rolled metal and comprising a sheet-metal body and steel strips attached to its edge, bridge and brace portions to reinforce the same.

As a new article of manufacture, a plate for an upright piano formed of rolled steel and comprising a body forming an upper and lower portion, steel strips attached to the edge, bridge and brace portions of the plate.

4. As a new article of manufacture an upright-piano plate formed of rolled steel and comprising a body forming an upper and lower part having narrow connecting-braces, and separate brace-strips attached to such narrow portions and extending from one part to the other.

5. A piano-plate comprising a rolled sheetmetal body portion and rolled steel strips attached to its bridge portions to raise and strengthen the same.

6. A piano-plate formed of rolled metal and comprising a body out from sheet metal, steel strips attached to said body to reinfmce the edges, brace sections secured to the body to stiffen the same, and rolled steel pieces secured to said body to form the several bridges for the strings.

7. As a new article of malnrfacture a pianoplate formed of rolled sheet-steel and comprising a body having oppositely-loealml bridge portions and steel strips attached to such bridge portions, attached steel strips extending transversely to and intermediate of such bridge portions to form braces.

S. A piano-plate comprising a rolled sheetmetal body and steel. strips attached to its bridge and brace portions to reinforce andv strengthen the same.

Signed at Stamford, in the county of Fairfield and State of Connecticut, this 22d day of November, A. l). 1904.

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