Patent · US Expired

Method and apparatus for monitoring a system for delivering secondary air to the exhaust gas internal combustion engine

US5406788A · kind A · utility

6Cited by
11References
5Claims
0Family size

Assignee

Inventors

Key dates

Filing dateSep 24, 1993
Grant dateApr 18, 1995
Priority date
Expiry dateSep 24, 2013

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02T10/40
  • WIPO fieldEnvironmental technology
  • WIPO sectorChemistry

Abstract

An apparatus for monitoring a system for delivering secondary air to an exhaust tube of an internal combustion engine. In the method and apparatus, a secondary air pump is switched on and builds up a pressure on the inlet side of a blocking valve which is normally closed and not being acted upon. The blocking valve has a valve closing member that is acted upon by a predetermined closing force of an elastic element. If the secondary air quantity pumped by the secondary air pump reaches a certain minimum air quantity and pressure, then with the then-opened blocking valve, a lambda sensor disposed in an exhaust tube detects a change in the lambda value in the exhaust tube that exceeds a predetermined threshold value. The apparatus is suitable for monitoring the function of a system for delivering secondary air to the exhaust tube of an internal combustion engine.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.