Patent EP0054887A2 successfully refreshed from Google Patents.
EP0054887A2
Expired / Lapsed
EP
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Air flow meter assembly
Assignee: Hitachi Ltd
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Filing: 1981-12-15
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Granted: —
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Expires: 2001-12-15
Abstract
Abstract An air flow meter for detecting the air flow supplied to an internal combustion engine. The air flow meter has a hot-wire (13) disposed in a by-pass air passage (8) opening at its one end to a portion of an air passage (2) upstream from a venturi portion (3) formed in said air passage (2) and at its other end in the venturi portion (3). The by-pass air passage (8) is provided to prolong a distance of length between the inlet opening of the by-pass passage (8) and the hot-wire (13), thereby to settle the flow of air in the by-pass passage (8) at least in the area around the hot-vire (13). The inlet opening of the by-pass air passage (8) may open in a plane perpendicular to the axis of the venturi portion (3) and within the area of upper projection of the venturi portion, to prevent carbon and oil particles from coming into the by-pass passage (8) thereby to prevent the contamination of the hot-wire (13).
Inventors
- 👤 Mineo Kashiwaya
- 👤 Kinsaku Yamada
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 08:25
CPC Classifications
G; G01; G01N; G01N15/00; F; F02; F02M; F02M35/00; F02M35/02; F02M35/0201; F02M35/021; F02D; F02D41/00; F02D41/02; F02D41/18; F02D41/187; G01F; G01F1/00; G01F1/68; G01F1/684; G01F1/6842; G01F5/00
Claims Analysis
Total Claims: 11
Claim 1
Independent Claim
175 words
An air flow meter assembly for internal combustion engines comprising: an air cleaner means for intaking air supplied to said engine; throttle valve means for controlling the air flow to be supplied to said engine; an air passage extending between said air cleaner means and said throttle valve means and having a venturi portion; a by-pass air passage having first and second passage sections, said first passage section of the by-pass air passage opening at its one end to a portion of said air passage upstream from said venturi portion for intaking air and at its other end into said venturi portion and including means for detecting the air flow through said by-pass passage, and said second passage section of the by-pass air passage attached to the end opening of said first passage section at one end of said second passage section and providing a desired length between the other end of said second passage section and said means for detecting the air flow, so as to settle the air flow in said by-pass passage.
Claim 2
Dependent Claim
175 words
An air flow meter assembly for internal combustion engines comprising: an air cleaner means for intaking air supplied to said engine; throttle valve means for controlling the air flow to be supplied to said engine; an air passage extending between said air cleaner means and said throttle valve means and having a venturi portion; a by-pass air passage having first and second passage sections, said first passage section of the by-pass air passage opening at its one end to a portion of said air passage upstream from said venturi portion for intaking air and at its other end into said venturi portion and including means for detecting the air flow through said by-pass passage, and said second passage section of the by-pass air passage attached to the end opening of said first passage section at one end of said second passage section and providing a desired length between the other end of said second passage section and said means for detecting the air flow, so as to settle the air flow in said by-pass passage.
Claim 3
Dependent Claim
56 words
An air flow meter assembly as claimed in Claim 1, wherein said first passage section has a cylindrical form, and the distance between an inlet opening of said by-pass air passage and said means for detecting the air flow is selected to .be at least twice as large as the diameter of said first passage section.
Claim 4
Dependent Claim
31 words
An air flow meter assembly as claimed in Claim 1 or 2, wherein said one end opening of said first passage section opens to a land provided on said air passage.
Claim 5
Dependent Claim
27 words
An air flow meter assembly as claimed in Claim 1 or 2, wherein the cross-sections of said first passage section and said second passage section are identical.
Claim 6
Dependent Claim
46 words
An air flow meter assembly as claimed in Claim 1, wherein said inlet opening of said by-pass air passage opens within the area of upper projection of said venturi portion of said air passage and along a plane perpendicular to the axis of said venturi portion.
Claim 7
Dependent Claim
29 words
An air flow meter assembly as claimed in Claim 5, wherein said inlet opening of said by-pass air passage opens substantially perpendicularly to the axis of said venturi portion.
Claim 8
Dependent Claim
23 words
An air flow meter assembly as claimed in Claim 1 or 5, wherein said means for detecting air flow includes a hot wire.
Claim 9
Dependent Claim
30 words
An air flow meter assembly as claimed in Claim 1 or 5, wherein said second passage section of said by-pass air passage includes means for settling the flow of air.
Claim 10
Dependent Claim
31 words
An air flow meter assembly as claimed in Claim 1, wherein said first passage section of said by-pass air passage in formed to extend substantially in parallel with said air passage.
Claim 11
Dependent Claim
25 words
An air flow meter assembly as claimed in Claim 5, wherein said first passage section of said by-pass air passage has a substantially L-shaped form.
References Cited (Backward Citations)
No citation records indexed.
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