US319189A

US319189A - John beinsmead

Info

Publication number: US319189A
Authority: US
Publication date: 1885-06-02
Anticipated expiration: 1902-06-02

Description

(No Model.) BRINSMEAD.

PIANO SOUNDING BOARD. No. 319,189. Patented June 2, 1885.

WITNESSES INVENTOR BYjza ATTORNEYS.

UNITED STATES PATENT OFFICE.

JOHN BRINSMEAD, OF LONDON, ENGLAND.

PIANO SOUNDlNG-BOARD.

SPECIFICATION forming part of Letters Patent No. 319,189, dated June 2, 1885.

Application filed November 8, 1884.

To all whom it may concern:

Be it known that 1, JOHN BRINSMEAD, of the firm of John Brinsmead 8t Sons, of Vigmore Street, London, England, piano-forte manufacturers, a subject of the Queen of Great Britain, have invented a certain new and useful Piano-Forte Sound-Board Adjustment, of which the following is a specification.

The object of my invention is to enable the sounding-board or belly of a piano-forte to be adjusted for the purpose of readily obtaining or restoring the proper bearing of the strings on all parts of the belly-bridge, in order to compensate for any inequalities of grain at different parts of the sounding-board, or for any yielding of thesounding-board under the pressure of the strings. By means of this adjustment great purity of tone may be obtained and maintained.

My invention consists in such a mode of fixing the sounding-board to the bracings that a leverage is obtained, whereby the soundingboard may be raised or bellied more or less to- Ward its center, as required for the purposes of the said adjustment. This leverage is obtained by placing the fillet by which the soundingboard is usually attached to the bracings at a distance from the edge of the sounding-board, instead of at the extreme edge, as usual, and applying pressure to the overhanging edge of the sounding-board, the said fillet acting as a fulcrum. Thisleverage arrangement does not in any Wayinterfere with the vibration of the sounding-board, to any or all of the edges of which it may be applied, as may be required.

The accompanying drawing represents the cross-section of one edge of a soundingboard fixed in the manner described.

A is the sounding-board, of suitable dimensions and shape, but preferably of slightlydiminished thickness toward the edge, and a is one of the bars at the back by which the sounding-board is stiffened, as usual.

B is the bracing or part of the frame to which the sounding-board is attached, and G is the fillet, placed at a distance of about two (N0 model.) Patented in England August 16, 1881, No. 3,557.

inches, more or less, from the edge of the sounding-board. This fillet is notched to receive the bars a, and is glued both to the sounding-board and the bracings or frame. Through the overhanging portion of the sounding-board are passed screws D, which screw into the braeings or frame B, and apply pressure, which tends to draw the edges ofthe sounding-board toward the braeings and to throw the central portion in the opposite direction, so as to counterbalance the bearing of the strings.

E is a narrow strip of hard wood glued along the edge of the sounding-board, and d is a washer to distribute the pressure of the screw. These screws are placed at suitable intervals apart along the edge of the soundingboard. Instead of common screws, I might use screw studs or bolts with nuts.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is 1. A piano-forte having its sound-board fixed to the bracings or frame by a fulcrum situated between the sound-board and bracings and at a distance from the edge of the former, and by screws bearing against the overhanging edge of the sound-board and producing aleverage action on the sound-board, substantially as specified.

2. In a piano-forte, the combination, with the sound-board, of a fillet situated at a distance from the edge of the sound-board and between it and the bracings, and of screws passing through and bearing against the overhanging edge of the sound-board and screwing into the bracings or frame, substantially as herein shown and described, and for the purpose specified.

JOHN BRINSMEAD.

\Vitn esses:

J NO. DEAN, J. \VATT, Both of 17 Graccclzm'ch St, London.