Hot gas sensor device with improved thermal isolation from carrier plate

US5211053A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Peter Nolting · Bühl, DE
• Martin Holland · Auburn Hills, US
• Botho Ziegenbein · Reutlingen, DE
• Guenther Stecher · Leonberg, DE
• Detlef Baresel · Stuttgart, DE

Key dates

• Filing date: Feb 19, 1992
• Grant date: May 18, 1993
• Expiry date: Feb 19, 2012

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N27/12
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A gas sensor device has a carrier plate of ceramic or glass. The carrier has apertures which leave only strips in a spiral configuration connecting a middle region of the carrier to the outer region thereof. The apertures may be mere slits separating the connection strips or they may be apertures providing larger air gaps. On each middle region so provided on the carrier a sensor element is located that has two electrodes and a sensitive layer which establishes a conducting connection between the electrodes. The electrodes and the sensitive layer are directly applied to the upper surface of the middle region. The two electrodes are comb shaped and are placed in inter-digital configuration to define a meandering gap between them. On the underside of the middle region of the carrier a heating element for the sensor element is provided and, if desired, also a temperature measuring resistance for regulating the temperature produced by a heating resistor. Conducting paths are located on the connecting strips between the middle region and the outer region of the carrier for connecting a sensor element and its heater to circuits on the outer region of the carrier plate.