Electric keyboard of snap-contact type

An electric keyboard comprising two electric circuits, two laminae associated to said circuits and elastically deformable with a snap action from a stable configuration to an unstable configuration to complete said electrical circuits through the lamina in only one of its two configurations, a hollow body to house said two laminae, a depressable key, guide means on said hollow body for guiding said key and means connecting said key with said laminae to snap a first of said two laminae into its unstable configuration after a normal stroke of said key and the second of said two laminae after an extra stroke of said key, said connecting means comprising a first actuator cooperative with said first lamina, a spring element resiliently connecting said actuator with said key for causing the snap action of said first lamina at said normal stroke and a second actuator connected substantially rigidly to said key for causing the snap action of said second lamina at said extra stroke.

A keyboard comprising an electrical circuit and an elastically deformable lamina for going with a snap action from a stable configuration to an unstable configuration to complete said electrical circuit in only one of said configurations, wherein said lamina is of substantially square outline and comprises two substantially triangular windows cut from the lamina and defining a diagonal strip and two opposite pairs of edge strips, wherein both said edge strips have ends common to the ends of the diagonal strip and each of said strips has a permanent bend set into it to bow the diagonal strip in the stable configuration of the lamina.