Patent · US Expired

Air-fuel ratio control system for a stratified scavenging two-cycle engine

US6591794B2 · kind B2 · utility

18Cited by
33References
14Claims
0Family size

Assignee

Inventor

Key dates

Filing dateMar 12, 2002
Grant dateJul 15, 2003
Priority date
Expiry dateMar 12, 2022

Classification

  • Technology area (CPC F)Mechanical Engineering; Lighting; Heating
  • CPC primaryF02B2075/025
  • WIPO fieldEngines, pumps, turbines
  • WIPO sectorMechanical engineering

Abstract

An air-fuel ratio control system for a stratified scavenging two-cycle engine that facilitates the elimination of acceleration failure in the initial stage of acceleration due to the dilution of the air-fuel mixture when scavenging air is introduced. In a preferred embodiment, the control system includes a driving gear and a driven gear that are connected to a carburetor throttling valve for controlling output and an air valve for controlling the flow rate of the scavenging air, respectively. Improved acceleration is achieved by not increasing the amount of air relative to the increasing amount of air-fuel mixture initially being introduced by not engaging the gears until the throttling valve opens slightly from the idling position. When the throttling valve is wide open, the two gears engage with each other, thereby opening the air valve and maintaining a nearly constant flow rate ratio between the air-fuel mixture and the air. Alternatively, the control system may include a driving lever and a driven lever that are connected to a carburetor throttling valve and an air valve for controlling the flow rate of the air-fuel mixture and the scavenging air, respectively.

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