Membrane type keyboard for data entry which prevents damage by water ingress during use

摘要

The keyboard is for data processing equipment or similar. Three layers: a base sheet (10), a system of electrical switches (12, 14, 16) in tablet form, and a keyboard-patterned sheet (18) located over the functional surface of the switch system, are bonded together along at least the edge perimeter. Preferably the base sheet, cover sheet and connecting edge U-profile (22), are all cast together, en bloc. For this purpose, a resilient, hardening, plastic material is used. The encapsulation is cast in a totally enclosed mould. In addition to the procedure, the membrane keyboard itself is also claimed.