(57) Beneath each key (6,7) and carried by the keyboard support (2) there is a basically round-shaped elastic or elasticized element (8), the base of which lies on the keyboard support (2), such a round-shaped surface, which may be achieved by hot-pressing a rubber sheet, and on top of which there is a collar the aim of which is to provide a certain resistance to the key, thus distributing the deformation resistance to the key, thus distributing the deformation caused by the pressed key over the entire surface of the round-shaped element. In other words, the top collar, under the effect of the pressed key, moves parallel to itself, thus causing the uniform deformation of the entire rubber element (8).
The keyboard support (2) consists of a board or plate (12) on which a layer of plastic material (11) is injected in such a manner as to cover the edges and the ends of the board or sheet, while leaving the middle parts uncovered, thus forming a sort of grid.