Improvements in and relating to Piano-players, Player-pianos and the like.

摘要

28,507. Bryan, G. H. Dec. 10. Expression, controlling; blowing and exhausting air.-In an expression-controlling device for a piano-player, player-piano, or similar instrument, the normal pressure in the wind-chest is varied by adjusting the tension of a spring, or the position of a weight on a lever, connected to the governor or regulating-bellows. Temporary variations in the pressure for accenting purposes are obtained by the performer pressing the lever or performing some other operation, the movement being transmitted through rigid or inextensible means to the governor. A controlling-lever may be rotated in one plane to vary the normal pressure and in another plane to vary the temporary pressure. In one form of the invention, a lever is pivoted on the front of the instrument and connected at one end by flexible members and a bell-crank to the moving-board of the governor. The other arm of the lever carries a weight which is adjusted along the lever to vary the normal pressure in the wind-chest. A scale with expression marks upon it is provided above the lever to facilitate this adjustment. The performer varies the temporary pressure by pressing or lifting the lever. It is stated that the tone-quality of the sounds produced may be varied by suitably manipulating the lever, and that owing to the different inertias of the bass and treble piano hammers, the treble notes in a chord are accented. In a modification suitable for player-pianos, a lever carrying a weight is connected by a rigid link to the governor. A controlling-lever, adapted to rotate in an horizontal plane, is connected by links and a lever to the weight for adjusting it to vary the normal pressure. For varying the temporary pressure, another lever rotating in a vertical plane is mounted on a spindle journaled on a hinged key-slip. When the key-slip is folded down, a clutch connects this spindle to another, which is connected by suitable linkage to the lever carrying the weight. As an alternative to the clutch, the two spindles may be connected by a universal joint. Figs. 5 and 6 show another modification in which the normal pressure is varied by rotating the lever Q, R in an horizontal plane about the axis P. The position of a pin C engaging slots in levers pivoted at A and D respectively is thus adjusted, so varying the leverage of the weight W, which is in connexion with the governor E. To vary the temporary pressure, the lever Q R is rotated in a vertical plane about the axis Q O, so applying pressure to the moving-board of the governor E through the arrangement of links and lever shown. The lever Q R may be detachable or adapted to be folded up when playing manually. A pointer co-operating with lines on the tune-sheet may be provided on the controlling-lever.