Title:
THERMAL AIR FLOWMETER
Document Type and Number:
Japanese Patent JPH04174325
Kind Code:
A
Abstract:
PURPOSE:To remove adhering substances positively by accumulating executing degrees of the movable of the adhering substances, and repeatedly removing the adhering substances every time a predetermined operable state is gained until the accumulating value becomes not smaller than a predetermined value and the removal is detected to be completed. CONSTITUTION:An electronic control device 2 sets a referential jetting amount on the basis of the sucking amount of air indicated by an air sucking signal from a thermal air flowmeter 7 and the rotating number of the engine indicated by an engine rotating number signal from a crank angle sensor 17. Moreover, the device 2 sets a feedback correcting amount so as to converge the air-fuel ratio of a mixed gas to a predetermined target ratio on the basis of the air-fuel ratio signal from an O2 sensor 22. The actual fuel jetting amount is obtained from the referential jetting amount and the feedback correcting amount, and output as a fuel jetting signal. When a predetermined operable state is gained every predetermined interval, a signal to clean the flowmeter 7 with heat is generated. The removing degree of adhering substances is accumulated. The adhering substances are repeatedly removed every time the predetermined operable state is obtained until the accumulating value is not smaller than a predetermined value and the removal is detected to be completed.
Inventors:
YAMAMOTO YOSHIAKI
KAJI TAKASHI
KAJI TAKASHI
Application Number:
JP30056890A
Publication Date:
June 22, 1992
Filing Date:
November 06, 1990
Export Citation:
Assignee:
TOYOTA MOTOR CORP
NIPPON DENSO CO
NIPPON DENSO CO
International Classes:
G01F1/68; G01F15/12; (IPC1-7): G01F1/68