Combined acoustic and electronic piano in which the acoustic action is disabled when played in the electronic mode

Abstract

An improved combination acoustic-mode and electronic-mode piano is provided which includes a hammer shank stop rail that intercepts the hammer shank, when in the electronic mode, so that the hammer cannot complete its normal travel and cannot strike its corresponding string(s) when its piano key is actuated. The hammer shank stop rail is actuated by an intermediate crank that, in turn, is actuated by a pedal dowel attached to one of the pedals of the piano. When operated in the acoustic mode, the stop rail occupies a position that will not interfere with the hammer shank's movements, and when in the electronic mode, the stop rail intercepts the hammer shank so that its associated hammer will not be able to travel all the way into contact with their associated string. A second embodiment operates the stop rail by use of a cable and cam mechanism. A third embodiment uses a hand-actuator to operate the stop rail via a dowel and intermediate crank. In a fourth embodiment, a fluid-actuated hammer shank stop rail is located in a position similar to the mechanical hammer shank stop rail described hereinabove. The fluid-actuated hammer shank stop rail includes a rigid portion that provides support across the width of the piano and an expandable portion that is resilient and can be enlarged by the use of an internal fluid pressure, which intercepts the hammer shank before the associated hammer can strike their associated string. A fifth embodiment of a combination dual-mode piano is provided that utilizes a spring-loaded wippen-disabler to prevent the wippen from being actuated by the key tail when the associated key is struck. When placed into the electronic mode, the wippen-disabler is rotated into a position in which one of its extended members is forced against the bottom portion of the wippen and raises the wippen high enough into a position so that the capstan screw of the key tail cannot come into contact with the bottom surface of the wippen. In addition, a different portion of the wippen-disabler is rotated so that its associated spring comes into contact with the top of the key tail, thereby providing the person playing the piano with some mechanical feedback that will approximate the feel of a standard key action.