Key switch device, keyboard and electronic apparatus with key switch device

In a key switch device 3, a guide member 10 constructed of a first and a second links 14 and 15, which guides a vertical movement of a key top 9, is movably mounted on a support plate 2 with a mounting member 6 provided with a rotatably supporting portion 7 which rotatably supports a rotatable shaft 18 formed at a lower end of the first link 14 and a slidably supporting portion 8 which slidably supports a slidable shaft 20 formed at a lower end of the second link 15. The mounting member 6 is fixed on the support plate 2 with a first, second, and third adhesive layers 24, 25, and 26.