The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Feb. 23, 1999
Filed:
Mar. 05, 1997
Applicant:
Inventor:
Gerhard Hochgesang, Bad Neustadt, DE;
Assignee:
Preh-Werke GmbH & Co. KG, Bad Neustadt, DE;
Primary Examiner:
Int. Cl.
CPC ...
H01H / ;
U.S. Cl.
CPC ...
200515 ;
Abstract
This invention relates to a switch mat with key switches. In previously disclosed switch mats, switch chambers located under dome-shaped key caps were jointly vented. This affected key operation, and allowed soiling by dust and moisture. Here, each switch chamber has a ventilating channel with a filter layer that is permeable to air, for venting to and from the outside. In this design, the filter layer is formed by a filter matting that is dust and moisture-repellent. Because each switch chamber is separately vented to and from the outside, there is no mutual influence on operating forces of the key switches.