Patent · US Expired

Idle speed control system for vehicle engines

US4242994A · kind A · utility

15Cited by
5References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 5, 1977
Grant dateJan 6, 1981
Priority date
Expiry dateDec 5, 1997

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF02D2011/102
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

An idling speed control system for automotive vehicle engines is disclosed. A throttle valve bypass passage for intake air is provided with an air control valve of the on-off type. The air control valve is electrically energized by a pulse train of substantially constant pulse repetition rate and pulse duration modulation so that the duty cycle of the valve is varied according to deviation of the engine idling speed from a set point value. The pulse repetition rate of the energizing pulses is higher than the frequency at which the engine can respond to air supply pulsations in the intake manifold.

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