Mechanical system for musical instrument keyboards - has pneumatic servo-operation simulating dynamic inertia effect of normal keyboards

摘要

Keyboard instruments e.g. pianolas, harmoniums etc. which use electrical, electromagnetic or electronic means, differ in touch from a standard piano keyboard with its mechanical inertia effect. This effect is simulated by the present mechanism, which comprises a pressure element forming the underside of ech key and working in conjunction with a resistance element. the keyboard has whole tone and semitone keys with a support for the fulcrum of each key. An extension under each key has a projection which engages against a friction or contact lever on a support. The projections and levers can be manufactured from various materials, e.g. plastic, which offer a certain friction resistance yet are proof against wear. they can be fitted with anti-friction and sound damping material e.g. Cashmere fabric.