Patent EP0173946A1 successfully refreshed from Google Patents.
EP0173946A1
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EP
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Air flow meter
Assignee: Hitachi Ltd
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Filing: 1985-08-27
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Granted: —
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Expires: 2005-08-27
Abstract
Abstract An air flow meter including an air flow rate measuring tube (10) located in a main air passageway (4) and having an air inlet portion (2) and an air outlet portion (5) of a bypass passageway (3) formed therein. The air inlet portion (2) i& located substantially in a central portion of the cross-sectional surface of the main air passageway (4), and a hot wire type flow sensor (6) is mounted in the bypass passageway (3). The air flow meter is suitable for use with an internal combustion engine of an automative vehicle.
Inventors
- 👤 Yutaka Nishimura
- 👤 Yoshishige Oyama
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-05 05:42
CPC Classifications
F; F02; F02M; F02M19/00; G; G01; G01F; G01F5/00; G01F1/00; G01F1/68; G01F1/684; G01F1/6842
Claims Analysis
Total Claims: 6
Claim 1
Independent Claim
139 words
An air flow meter comprising: a main passageway; a bypass passageway maintained in communication with said main passageway; and a hot wire type air flow sensor mounted in said bypass passageway; characterized in that: an air flow rate measuring tube (10, 10A, 210, 310, 410, 510, 610, 710) is mounted in said main passageway (4, 104) and has an inlet portion (2, 2C2, 302, 402, 502, 602) and an air outlet portion (5, 5A, 205, 305, 405, 505, 605) for forming said bypass passageway (3, 3A, 203, 303, 403, 503, 603, 703) in the air flow rate measuring tube, said air inlet portion being located substantially in a central portion of the cross-sectional surface of said main passageway, and said hot wire type air flow sensor being mounted in the bypass passageway in the air flow rate measuring tube.
Claim 2
Dependent Claim
139 words
An air flow meter comprising: a main passageway; a bypass passageway maintained in communication with said main passageway; and a hot wire type air flow sensor mounted in said bypass passageway; characterized in that: an air flow rate measuring tube (10, 10A, 210, 310, 410, 510, 610, 710) is mounted in said main passageway (4, 104) and has an inlet portion (2, 2C2, 302, 402, 502, 602) and an air outlet portion (5, 5A, 205, 305, 405, 505, 605) for forming said bypass passageway (3, 3A, 203, 303, 403, 503, 603, 703) in the air flow rate measuring tube, said air inlet portion being located substantially in a central portion of the cross-sectional surface of said main passageway, and said hot wire type air flow sensor being mounted in the bypass passageway in the air flow rate measuring tube.
Claim 3
Dependent Claim
36 words
An air flow meter as claimed in claim 1, characterized in that said hot wire type air flow sensor comprises wound wire type probes (6, 206, 316, 406, 506, 606 and 7,207, 317, 407, 507, 607).
Claim 4
Dependent Claim
31 words
An air flow meter as claimed in claim 2 or 3, characterized in that said air flow rate measuring tube (10, 10A, 210, 310) is located transversely of said main passageway.
Claim 5
Dependent Claim
92 words
An air flow meter as claimed in claim 3, characterized in that said bypass passageway comprises a first passageway portion (314, 14A) contiguous with said air inlet portion and extending lengthwise of said main passageway, and a second passageway portion (315, 15A) located substantially at right angles to said first passageway portion and extending lengthwise of said air flow rate measuring tube, said second passageway portion being contiguous at opposite ends thereof with openings (305, 15A) of said air outlet portion located at opposite sides of the air flow rate measuring tube.
Claim 6
Dependent Claim
31 words
An air flow meter as claimed in claim 1 or 2, characterized in that said air flow rate measuring tube (410, 510, 610, 710) is located lengthwise of said main passageway.
References Cited (Backward Citations)
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