Patent GB-287310-A (GB)
Title: Improved accenting or expression means for player pianos
IPC: G10C3/20
Filed: 1927-03-07
Abstract: 287,310. Marks, E. C. R., (Auto Pneumatic Action Co.). March 7, 1927. Player-pianos ; expression - controlling ; tunesheets.-In a pneumatic player-piano, the sections of a divided hammer rest-rail are automatically moved gradually or quickly either to one of three set positions, or to any position within the range, in which position they may be held by small alternating apertures in the tune-sheet. When the automatic actuation of the rail-sections is out of action, they may be controlled by hand. The loud pedal may be actuated from two special tracker-holes, a switch being provided to transfer the actuation to the usual tracker-hole when the automatic actuation of the rest-rail sections is out of action. The treble and bass rest-rail sections H<1>, Fig. 2, are connected by links L<6> through springs L', Fig. 21, to oppositely arranged bell-cranks L<4> which are connected by links L<3> to the setting lever L pivoted at L<1>. When the finger-lever L is to the left, held by a spring L<8>, the sections H<1> rest against the main rail H, and are operable from spring-connected finger-levers 60, 64 through links 61, 63 and bell-crank 62. To set the apparatus for automatic actuation, the lever L is moved to the right where it is held by a catch, the rail sections being brought forward to a normal position producing softest playing. Special holes 1 - - 6 at each end of the trackerbar control the actuating pneumatics W<1> which are connected to the rail sections by links 10. A stop-pneumatic X', also arranged on the valvebox V<1>, by means of a lug 12 holds the pneumatic W<1> and rail-section H<1> in an intermediate position. A tracker-hole 2 when uncovered lifts a diaphragm and valve 24, Fig. 12, to admit suction by passage 25 to the pneumatic X<1>, the valve being held open after passage of the tune-sheet aperture owing to admissionof air at 26 by a valve 21 raised simultaneously with the valve 24. The pneumatic X<1> is allowed to expand on the passage of a tune-sheet aperture over tracker-hole 1, which, by admitting air to a chamber 27, closes valve 21. By similar valve mechanism, on passage of a tune-sheet aperture at 4 the pneumatic W<1> is connected to suction through an adjustable restricted passage, slowly collapsing and giving crescendo. An aperture at 3 restores this valve mechanism permitting the pneumatic to fill through another restricted passage, thus giving diminuendo. A similar valve, but without auxiliary holding-on valve, on passage of an aperture at 6 collapses the pneumatic W<1> quickly through a large adjustable passage, the period of complete collapse corresponding to the length of the tune-sheet aperture. To allow the pneumatic W<1> to expand quickly, an aperture at 5 opens an atmosphere valve in the part 43 of the valve box. To hold the pneumatic W<1> at any position within its range, it can be moved slowly or quickly in either direction and maintained at the desired point by a series of alternating apertures 4, 3, 4, 3 .. in the tune-sheet. The loud-pedal pneumatic W' is collapsed from a tracker-hole 8, lifting a valve similar to valve 21 but which however serves both as its own holding-on valve and also to admit air to a tube 53 operating a further valve in turn operating a pair of valves controlling the pneumatic W<3>. The duplication of these lastmentioned valves ensures powerful operation of the pneumatic. An aperture at 7 releases the loud-pedal pneumatic. To enable the loud pedal to be actuated if desired from the usual tracker-hole 3, this hole is connected through a rotary switch 69 which, when the setting-lever L is released from its right-hand position, changes over the connection of the tube 3 from the valvebox V<1> of the rest-rail, to a nipple 71 connected to the tube 53 and valve-box V<3> of the loudpedal. A finger-valve 74, for manual operation of the loud pedal, is also connected to the nipple 71.