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:
Mar. 17, 1981
Filed:
Aug. 09, 1979
Maurice Boutonnat, Gouvieux, FR;
Gerard Rose, Villers St-Paul, FR;
Charbonnages de France, Paris, FR;
Abstract
A measuring cell having a measuring filament and a reference filament is disposed in a cap of sintered metal. A time base circuit, actuated by the closing of a switch, connects the filaments to an electrical supply circuit after a predetermined delay. Subsequently, the time base circuit sequentially triggers the connection of the filaments to a measuring circuit, the storage in a memory of the value of the output signal of the measuring circuit and the display of this stored value, the disconnection of the supply circuit, and the illumination of an end of operation warning lamp. The value displayed is proportional to the amount of a constituent of an atmosphere diffused into the measuring cell. The apparatus can be used as a portable fire damp meter or explosimeter.