Gas-permeable connecting lead for a probe

US6018982A · kind A · utility

Assignee

• Robert Bosch GmbH · DE

Inventors

• Karl-Hermann Friese · Leonberg, DE
• Helmut Weyl
• Anton Hans · Ludwigsburg, DE

Key dates

• Filing date: May 26, 1998
• Grant date: Feb 1, 2000
• Expiry date: May 26, 2018

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N27/4076
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

A Lambda probe type gas sensor for use in determining the oxygen content of exhaust gases produced by an internal combustion engine includes a sensor element of the electrochemical, solid electrolyte, metallic oxide semiconductor or Lambda air-fuel ratio variety, which sensor element is arranged in a metallic housing and is contacted by connecting cables that are brought out of the metallic housing. These connecting cables are each surrounded by cable insulation that is made of PTFE (Polytetra-fluoroethylene). The surface of the cable insulation has, at least in certain areas, a gas-permeable section that allows a reference atmosphere to arrive inside the cable insulation and, from there, in the metallic housing. The gas-permeable section, on the other hand, prevents ingress of liquids such as fuel, condensed water, etc., This is achieved, for example, by an additionally applied, PTFE film that is placed over the gas-permeable section.