Improvements in and connected with piano players, or player pianos

摘要

322,492. Cooklin, I., and Baker, J. C. Sept. 6, 1928. Expression-controlling.-In apparatus operated either by pressure or suction, the expression is controlled by varying the cross-section of the passage ways between the valves and the striking- pneumatics. This may be done by mounting over each port 13 leading from a valve 7 by a rubber tube to a strikng-pneumatic, a split ring 14 spanned by a fork 17. The forks 17 are connected together by a bar 16 and are operated, to open or close the ports 13 more or less, by hand or from the tracker-bar.