Patent · US Expired

Idle speed control device for an engine

US5513610A · kind A · utility

3Cited by
3References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 19, 1995
Grant dateMay 7, 1996
Priority date
Expiry dateApr 19, 2015

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF02D2011/103
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

The idle speed control device according to the present invention controls a two-solenoid rotary type idle speed control valve properly even when one of the solenoids fails. When one of the solenoids fails, the device calculates the amount of bypass air from the amount of inlet air and the degree of opening of the throttle valve, and estimates the degree of opening of the idle speed control valve. If the degree of opening of the bypass valve is larger than that of the neutral valve position, the device sets the duty ratio of the control signal for driving the idle speed control valve at 0%, and if the degree of opening of the idle speed control valve is less than that of the neutral valve position, the device sets the duty ratio of the control signal at 100%. By this control, the two-solenoid rotary type idle speed control valve is maintained at neutral valve position without determining the type of the failure of the solenoids precisely.

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