Abstract: A keyboard assembly includes a printed circuit board having conductive paths defining a plurality of switch sites. Contact terminals are connectable in electrical circuits with the conductive paths. The assembly also includes an electrically-groundable conductive panel overlying the board and having a plurality of apertures defined therein in registry with the switch site. A dielectric layer is disposed between the panel and board providing electrical isolation therebetween. A plurality of individually-replaceable EMI RFI-shielded switch modules are installed in registry with the apertures on the conductive panel, in overlying relation to the switch sites, and electrically connected to the conductive panel.

Abstract: An internal pinion revolution counter includes a bearing member rotatably supporting an input shaft. At least first and second number wheels are provided each having a radially outwardly extending web portion joined to an annular flange portion, the first and second number wheel flange portions respectively extending toward each other. Each web portion has an annular bearing surface which defines a central opening. The flange portion of the first number wheel has an internal gear segment and cooperating internal locking cam formed thereon, and the flange portion of the second number wheel has an internal full tooth gear formed thereon. The first number wheel is connected to the input shaft for rotation therewith. A pinion carrier is arranged within the center opening in the web portion of the second number wheel, surrounds the input shaft, and is secured against rotation with respect to the input shaft.

Abstract: An internal pinion revolution counter includes a rotatable input shaft having first and second axial sections, and a bearing sleeve member rotatably supporting the first shaft section. A gear member is rotatably mounted on the sleeve member and has first and second axial sections, the first section having a first full tooth spur gear formed thereon. A first number wheel is secured to the second shaft section for rotation therewith, and an internal pinion transfer mechanism couples the first number wheel to the first spur gear. A second number wheel has a web portion joined to a hub portion mounted on the first spur gear for rotation therewith, and the second section of the gear member has a spur gear segment formed thereon as an extension of the first spur gear. A locking ring has a hub portion mounted on the second section of the gear member, and having an axial slot formed therein with the gear segment extending therethrough, the hub portion of the locking ring having an annular outer locking cam surface.