GB190801191A - Improvements in Tone subduing or Note-accenting Mechanism for use with Pianos Played by Mechanical Piano-players. - Google Patents

Abstract

1191. Howard, S. Jan. 18. [Patent of Addition to No. 12,738, A.D. 1906.] Automatic instruments.-An expression device by which any note or series of adjoining notes can be distinguished from the rest of a chord by being muted or left unmuted, as described in Specification No. 12.738, A.D. 1906, is arranged to operate pneumatically. A muting-flap e<1>, Fig. 3, is brought into action, or a lever e is moved to shorten the stroke of the piano hammer b, when suction is admitted by a tube k to collapse a pneumatic c, one of these muting-devices being provided for each two notes, or for more than two in the end parts of the register. The tubes k are connected to apertures g, Fig. 2, in a valve box f, which is exhausted through apertures h, and each end of the valve box is fitted with a sliding valve l, which is controlled by a lever at the front of the instrument to admit atmospheric pressure through a groove m to any number of the apertures g. Thus the notes corresponding to the apertures g between the two valves l are muted, the rest being fully sounded ; but the arrangement may be varied to reverse this effect. The valves l are each made in two spring-separated parts to maintain a good fit with the valve box. Alternatively, a rotary form of valve may be used. There may be two valve-boxes for controlling different parts of the register. Pressure may be used instead of suction, and in that case the ends of the valve box may be fitted with exhaust boxes for admitting suction to the grooves m. The pneu. matics c may act on the hammers directly. The invention is applicable to separate players. According to the Provisional Specification, a safety-valve may be provided, and each muting-device may be governed by an independent slide valve.