Touchpad keyboard
First Claim
1. A keyboard comprising a printed circuit board, a plurality of spaced conductor pairs on a surface of said printed circuit board, a web of compressible material having one side abutting said surface of said printed circuit board and provided with apertures centered on said conductor pairs, a rigid disc comprising conductive material in each of said apertures and having a flat surface facing each of said conductor pairs, and means comprising a flexible plastic sheet covering the side of said web opposite said one side and connected to the sides of the discs opposite said flat surfaces for retaining said discs in said apertures at a position normally spaced from said printed circuit board, said discs being thinner than said web, whereby pressure on any of said discs in a direction toward said printed circuit board causes the flat surface of said one of said discs to move to a position abutting said printed circuit board and bridging said corresponding conductor pair.
1 Assignment
0 Petitions
Accused Products
Abstract
An improved capacitive keyboard uses a standard printed circuit board provided in various locations with spaced conductor pairs. A conductive disc with a flat insulated lower surface is aligned above each conductor pair. All of the discs are suspended above the printed circuit board within apertures of a web of polymer foam material and held in position by a sheet of adhesive covered plastic that covers and adheres to the entire upper surface of the web and each of the discs.
-
Citations
7 Claims
- 1. A keyboard comprising a printed circuit board, a plurality of spaced conductor pairs on a surface of said printed circuit board, a web of compressible material having one side abutting said surface of said printed circuit board and provided with apertures centered on said conductor pairs, a rigid disc comprising conductive material in each of said apertures and having a flat surface facing each of said conductor pairs, and means comprising a flexible plastic sheet covering the side of said web opposite said one side and connected to the sides of the discs opposite said flat surfaces for retaining said discs in said apertures at a position normally spaced from said printed circuit board, said discs being thinner than said web, whereby pressure on any of said discs in a direction toward said printed circuit board causes the flat surface of said one of said discs to move to a position abutting said printed circuit board and bridging said corresponding conductor pair.
Specification