公开(公告)号：US3745287A

公开(公告)日：1973-07-10

申请号：US3745287D

申请日：1971-10-01

Applicant: ADDMASTER CORP

Inventor： WALKER W

IPC: H01H13/702 ,  H01H13/785 ,  H01H13/52 ,  H01H1/06 ,  H01H13/06

CPC classification number: H01H13/785 ,  B41J5/08 ,  H01H13/702 ,  H01H2201/03 ,  H01H2203/01 ,  H01H2203/02 ,  H01H2215/002 ,  H01H2221/024 ,  H01H2221/042 ,  H01H2229/032

Abstract: A key operated diaphragm type switch comprising a printed circuit board base having conductors thereon, a flexible sheet of non-conductive material supported in taut condition over the base and having an opening therein aligned with adjacent terminal portions of certain of the conductors, and a layer of unwoven matted metal fibers on the order of .10 in. thick overlying the sheet. Upon depression of the key, the underlying portion of the metal fiber layer and the flexible sheet are pressed toward the base. The portion of the metal fiber layer underlying the key is deformed through the opening in the flexible sheet and into bridging contact with the conductors to close the switch.