Key, input unit using such key, and control system comprising such input unit and electronic apparatus acoustically connected to such input unit

摘要

A key for transmitting data to an electronic apparatus includes a key top, a sound generating mechanism connected to the key top for generating a predetermined sound without any electrical power supply when the key top is depressed, and an outer sleeve receiving the sound generating mechanism. The outer sleeve has an opening portion for outputting the sound to the outside so that the sound can be received by the electronic apparatus. The acoustic communication system between an input unit and the electronic apparatus may dispense with any cable there between and also dispense with any electrical power supply for the input unit.