Vacuum detection switch
US5998745A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 31, 1998 |
| Grant date | Dec 7, 1999 |
| Priority date | — |
| Expiry date | Mar 31, 2018 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01H35/34
- WIPO fieldElectrical machinery, apparatus, energy
- WIPO sectorElectrical engineering
Abstract
A switch detects a vacuum that is created by suctioning air through a port hole in a media support surface. The switch includes a first layer having (i) a first hole therein which is at least partially aligned with the port hole in the media support surface and (ii) a conductive region, and a second layer, which is disposed above the first layer relative to the media support surface and which is substantially non-conductive. The second layer has a second hole therein which aligns, at least in part, to the first hole in the first layer and to the port hole in the media support surface so as to allow air to flow through the port hole, the first hole, and the second hole. A third layer, which is disposed above the second layer relative to the media support surface, comprises a printed circuit pattern that aligns, at least in part, to the second hole. The printed circuit pattern on the third layer comprises an open circuit. When air is suctioned through the port hole, the first hole and the second hole, a vacuum is created which draws at least a part of the printed circuit pattern through the second hole and into contact with at least a part of the conductive region of the first layer …
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.