Patent · US Expired

Engine idle speed control device

US7169078B2 · kind B2 · utility

3Cited by
1References
16Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 28, 2005
Grant dateJan 30, 2007
Priority date
Expiry dateAug 24, 2025

Classification

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

Abstract

An engine idle speed control device set a target idle speed NsetN for a non-traveling range is set to a high value to activate the catalytic converter early, after the engine is started. Upon detecting that the automatic transmission has been shifted from a non-traveling range to a traveling range, the target idle speed is lowered to a first traveling idle speed Nset1. A feedback gain G used for feedback control of the ignition timing is then set to a larger gain value. The larger gain value is set such that it varies based on the temperature of the automatic transmission fluid or other parameter indicative of the engine friction and/or automatic transmission friction. As a result, the ignition timing is retarded in a precise manner, the engine speed is reduced, and the clutch engagement shock is reduced.

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