Abstract: An automatic player piano is a combination between an acoustic piano and an automatic playing system, and a grand piano and an upright piano are used as the acoustic piano; the grand piano has action units prompter than action units of the upright piano so that a half-stroke recorded through the grand piano is not reproducible by the upright piano; the automatic playing system causes the hammers to rotate toward the strings without any escape thereby compensating the poor promptness with the short keystroke of the keys until the rotation of hammers.

Abstract: A system for adapting a tracker bar operated automatic musical instrument to play electronically stored performances includes, in one embodiment family, a channel plate member having parallel channels in the upper face. First and second spaced apart holes are provided in each channel. An array of solenoid operated valves individually open and close first holes in the channels in response to energizing signals selectively applied to the solenoid coils. The second holes are oriented to interface with the tracker bar holes so that opening a given solenoid operated valves exposes the corresponding tracker bar hole to atmospheric via the corresponding channel. Left and right adjustable bracket assemblies are adapted to respectively engage the left and right pay-off spool mounting members to juxtapose and maintain the channel plate member in the operating position.

Abstract: A pump for pumping shear sensitive material comprising a housing having an internal displacement chamber and a displacement rod. The displacement rod is reciprocable within the displacement chamber and the displacement chamber having an aperture through which the displacement rod is reciprocated. The aperture being sealed with respect no the displacement chamber by the displacement rod and an annular seal surrounding the displacement rod. The displacement chamber having an inlet opposite the aperture and an outlet radially disposed to the longitudinal axis of the displacement rod and in close proximity to the annular seal.