Brinks Hofer Gilson & Lione
Keyboard apparatus free from incorrect fitting of key-top in type and fitting direction thereof
 When plural types of key-switch bodies arranged on a keyboard base are fitted with the corresponding types of key-tops, fitting of an incorrect key-top on a key-switch is avoided. Each key-top has a key-top side assortment cord comprising a unique combination of convex portions and concave portions which is determined by the type thereof, and a housing of each key-switch body has a body side assortment cord comprising a unique combination of convex portions and concave portions engageable with the key-top side assortment cord in pairs. The key-tops can be fitted to the key-switch bodies only when the key-top side assortment cord is brought into engagement with the body side assortment cord. 
Alps Electric Co., Ltd.
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