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:
Apr. 07, 1992
Filed:
Dec. 10, 1990
Yuji Miyahara, Hitachi, JP;
Keiji Tsukada, Katsuta, JP;
Yasuhisa Shibata, Ibaraki, JP;
Hiroyuki Miyagi, Kokubunji, JP;
Hitachi, Ltd., Tokyo, JP;
Abstract
A planar oxygen sensor has an insulating substrate, a cathode formed on the insulating substrate generally at the center thereof; another electrode formed on the insulating substrate in a region other than the region of the cathode, a gas permeable membrane stretched to cover these electrodes and having its peripheral portion supported on the insulating substrate, and an electrolytic solution charged between the gas permeable membrane and the insulating substrate. A surface of the cathode is substantially in contact with the gas permeable membrane and is formed at a position higher than the gas permeable membrane support portion of the insulating substrate. A portion of the insulating substrate surface other than the region where the cathode is formed is recessed. Because the layer of electrolytic solution on the cathode is thin, oxygen molecules passing through the gas permeable membrane can immediately serve for the reduction at the cathode, thereby increasing the response speed of the planar oxygen sensor. Also, the amount of electrolytic solution is increased by the recess to extend the life of the sensor.