ACTION FLANGE OF PIANO AND ITS PRODUCTION

摘要

PURPOSE: To provide an action flange of a piano which does not hinder action motion in spite of the change in relative humidity and a process for producing the action flange. CONSTITUTION: Flange members 2 made of a synthetic resin having bored flange holes 2a and wool bushing cloth 4 formed into a flat planar shape are prepd. The bushing cloth 4 is rounded into a cylindrical shape and is fitted into the flat holes 2a of the flange member 2. Both ends of a center pin 6 are fitted into the hole 4a of the bushing cloth 4 to form the action flange 10 prior to a treatment. The action flange is soaked for 7 minutes at 80 deg.C in water contg. a surfactant and is dried and is rested until an equil. moisture content is attained. The action flange 1 of the piano obtd. in such a manner is 10g/cm in the initial torque of a rotatably supported center pin 6 and the change rate of the torque thereof when the relative humidity is changed from 60% to 90% at 25±3 deg.C is 170%.