| 摘要 |
<p>A switch for use in data operations has a cap (12), a stem (14) adapted to be releasably attached to the cap, a core (16) attached to the stem for movement therewith, a housing (20) having a plate with opening therethrough, the opening being sized and shaped to allow for axial movement relative thereto by the stem; the core being capable of inducing on/off signals in a circuit panel to which the switch is to be attached. Also disclosed is a circuit panel to which the switch is to be attached and which has a single layer mylar sheet having at least one aperture (68) therethrough adapted to receive therein the core, there being one aperture per switch. The aperture is axially aligned with the passage when the switch is fitted. The sheet has a printed circuit layer on at least one of either the upper or lower surfaces thereof, the printed circuit layer including a scan line (72) and a return line (74) adjacent the aperture. Also disclosed is a switch circuit including a central processing unit (23) and a key matrix (11), the key matrix including a circuit panel and a number of switches, as well as a multiplexer (13) to select the source of the return signals. A latch circuit is provided which reads and removes any return signal after it is read, and an input/output connector is used to cause the keys to be scanned via the scan line.</p> |
