Patent · US Expired

Air fuel ratio control system for furnace

US4585161A · kind A · utility

16Cited by
5References
8Claims
0Family size

Assignees

Inventors

Key dates

Filing dateMar 18, 1985
Grant dateApr 29, 1986
Priority date
Expiry dateMar 18, 2005

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T137/2529
  • WIPO fieldThermal processes and apparatus
  • WIPO sectorMechanical engineering

Abstract

An air fuel ratio control system comprises a first valve provided in a fuel pipe through which a fuel is supplied to a burner, a second valve provided in an air pipe through which air is supplied to the burner, a varying circuit for varying responsive to a preset flow rate of fuel a valve opening degree of each of the first and second valves while maintaining a constant ratio between the valve opening degrees of the first and second valves, so that an air fuel ratio of a flow rate of fuel flowing through the first valve and a flow rate of air flowing through the second valve assumes a value greater than a theoretical air fuel ratio, a first sensor for detecting a flow rate of fuel flowing through the fuel pipe, a second sensor for detecting a flow rate of air flowing through the air pipe, a fuel bypass pipe provided in the fuel pipe for bypassing the first valve, a third valve provided in the fuel bypass pipe, and a control circuit supplied with output signals of the first and second sensors for controlling a valve opening ratio of the third valve, so that the air fuel ratio assumes a predetermined air fuel ratio.

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