Operation setting device having stationary touch-sensitive control elements

摘要

The operation setting device includes a keyboard having stationary control keys arranged on a transparent support plate of insulating material, each key of the keyboard being formed of a pair of transparent electrically conductive material secured to the outer face of the support plate and being connectable to a switching device sensitive to a change of resistance between the contacts in each pair. A visual identification card is located behind the support plate and having its indentification signs in register with respective keys.