Patent · US Expired

Exhaust gas reflux apparatus

US4719894A · kind A · utility

2Cited by
6References
7Claims
0Family size

Assignee

Inventor

Key dates

Filing dateSep 30, 1985
Grant dateJan 19, 1988
Priority date
Expiry dateSep 30, 2005

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02T10/40
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

An exhaust gas reflux apparatus for an internal combustion engine. This apparatus comprises an EGR regulating valve to control the amount of exhaust gas which is refluxed into an intake system of the engine, an ignition coil to detect the rotating speed of the engine; a shift switch to detect the gear position of the change gear; a negative pressure change-over valve arranged in a negative pressure passage; and a control circuit which discriminates a high-speed and high-load operating state of the engine when the rotating speed is over a set speed and the change gear is at a set gear position on the high speed side on the basis of the detection signals from the ignition coil and shift switch. The control circuit controls the change-over valve to stop the reflux of the exhaust gas after expiration of a set time period when the high-load operating state is detected. The EGR regulating valve is thus not subjected to a high temperature for in excess of the set time period.

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