Title:
AIR-FUEL RATIO CONTROL DEVICE FOR A CARBURETOR
Document Type and Number:
WIPO Patent Application WO/2011/048871
Kind Code:
A1
Abstract:
Disclosed is an air-fuel ratio control device for an internal combustion engine. Said air-fuel ratio control device opens or closes a choke valve in accordance with a load and how open a throttle valve in a carburetor is, allowing variable fuel injection and making it possible to achieve a desired air-fuel ratio across the entire operable range (engine speed and load) of the internal combustion engine, resulting in reduced costs, cleaner exhaust gas, and improved fuel efficiency. The disclosed air-fuel ratio control device is provided with: a first stepping motor (8) that adjusts the degree of opening of a choke valve (6) in a carburetor (5) disposed on an air-intake passageway of an internal combustion engine (1); a second stepping motor (9) that adjusts the degree of opening of a throttle valve (7); and a controller (12) that obtains a desired air-fuel ratio. The controller controls the degree of opening of the choke valve (6) on the basis of changes in the speed of the internal combustion engine (1) that occur as the throttle valve (7) opens or closes, and if the speed of the internal combustion engine (1) is constant, the controller controls the degree of opening of the choke valve (6) on the basis of a map that determines the degree of opening of the choke valve (6) by the load on the internal combustion engine (1).
Inventors:
MAKI KAZUHIRO (JP)
Application Number:
PCT/JP2010/064337
Publication Date:
April 28, 2011
Filing Date:
August 25, 2010
Export Citation:
Assignee:
MITSUBISHI HEAVY IND LTD (JP)
MAKI KAZUHIRO (JP)
MAKI KAZUHIRO (JP)
International Classes:
F02M7/00; F02D9/02; F02D11/10; F02M7/12
Foreign References:
| JPS63167061A | 1988-07-11 | |||
| JP2008255881A | 2008-10-23 | |||
| JP2006329095A | 2006-12-07 | |||
| JPS51144833A | 1976-12-13 | |||
| JPS5187628A | 1976-07-31 | |||
| JP2007023838A | 2007-02-01 |
Other References:
See also references of EP 2492485A4
Attorney, Agent or Firm:
TAKAHASHI, MATSUMOTO & PARTNERS INTELLECTUAL PROPERTY CORP. (JP)
Patent business corporation Takahashi 松本 & partners (JP)
Patent business corporation Takahashi 松本 & partners (JP)
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