Patent US4445368A successfully refreshed from Google Patents.
US4445368A
Expired / Lapsed
US
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Air flow rate meter apparatus
Assignee: Robert Bosch GmbH
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Filing: 1982-06-25
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Granted: 1984-05-01
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Expires: 2002-06-25
Abstract
Abstract A air flow rate meter apparatus includes an air bypass line, which branches off from a filter housing on the air intake fitting of an internal combustion engine and discharges at a restriction of the air intake tube upstream of a throttle valve. An injection valve is disposed in the restricted section, ejecting fuel in the direction toward a throttle valve. The air bypass line extends vertically and has a first U-shaped section, the connecting portion of which is located at a lower level than its legs. A temperature-dependent resistor in the form of a hot wire or hot strip is disposed in the downstream leg of the first U-shaped section, so that during a burnoff procedure of the temperature-dependent resistor a flow is effected in the direction toward the mouth of the air bypass line, thus preventing the aspiration of a fuel-air mixture into the air bypass line and thus avoiding the danger of ignition with the possible destruction of the temperature-dependent resistor.
Inventors
- 👤 Jaihind S. Sumal
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-31 17:38
CPC Classifications
G; G01; G01F; G01F1/00; G01F1/68; G01F1/684; G01F1/6842; G01F1/696; G01F1/698; G01F1/6983
Claims Analysis
Total Claims: 8
Claim 1
Independent Claim
168 words
An air flow rate meter apparatus in an air intake of an internal combustion engine, comprising: an air flow conduit having a restriction; an air bypass line through which air flows which is at a predetermined proportion with respect to the mass of air flowing through the air flow conduit; an air flow rate meter device disposed within the air bypass line, said air flow rate meter device including at least one temperature-dependent resistor, wherein: at least one of temperature and resistance of said at least one temperature-dependent resistor is regulated in accordance with the mass of flowing air; the air bypass line includes a mouth which opens into the air flow conduit at its restriction, closure means which prevents a flow of air through the air bypass line mouth toward said at least one temperature-dependent resistor and a servomotor adjustable by means dependent on negative pressure for actuating said closure means wherein the air bypass line is closeable at one of its ends by said closure means.
Claim 2
Dependent Claim
168 words
An air flow rate meter apparatus in an air intake of an internal combustion engine, comprising: an air flow conduit having a restriction; an air bypass line through which air flows which is at a predetermined proportion with respect to the mass of air flowing through the air flow conduit; an air flow rate meter device disposed within the air bypass line, said air flow rate meter device including at least one temperature-dependent resistor, wherein: at least one of temperature and resistance of said at least one temperature-dependent resistor is regulated in accordance with the mass of flowing air; the air bypass line includes a mouth which opens into the air flow conduit at its restriction, closure means which prevents a flow of air through the air bypass line mouth toward said at least one temperature-dependent resistor and a servomotor adjustable by means dependent on negative pressure for actuating said closure means wherein the air bypass line is closeable at one of its ends by said closure means.
Claim 3
Dependent Claim
187 words
An air flow rate meter apparatus, comprising: an air flow conduit having a restriction; an air bypass line through which air flows which is at a predetermined proportion with respect to the mass of air flowing through the air flow conduit; an air flow rate meter device disposed within the air bypass line, said air flow rate meter device including at least one temperature-dependent resistor, wherein: at least one of temperature and resistance of said at least one temperature-dependent resistor is regulated in accordance with the mass of flowing air; the air bypass line includes a mouth which opens into the air flow conduit at its restriction, and is embodied such that, at least under predetermined operating conditions, a flow of air through the air bypass line mouth toward said at least one temperature-dependent resistor is prevented; said air bypass line further includes a first U-shaped section having two legs and a connecting portion, further wherein: the air bypass line extends vertically; the connecting portion is located vertically lower than the two legs; and said at least one temperature-dependent resistor is disposed downstream of the connecting portion.
Claim 4
Dependent Claim
187 words
An air flow rate meter apparatus, comprising: an air flow conduit having a restriction; an air bypass line through which air flows which is at a predetermined proportion with respect to the mass of air flowing through the air flow conduit; an air flow rate meter device disposed within the air bypass line, said air flow rate meter device including at least one temperature-dependent resistor, wherein: at least one of temperature and resistance of said at least one temperature-dependent resistor is regulated in accordance with the mass of flowing air; the air bypass line includes a mouth which opens into the air flow conduit at its restriction, and is embodied such that, at least under predetermined operating conditions, a flow of air through the air bypass line mouth toward said at least one temperature-dependent resistor is prevented; said air bypass line further includes a first U-shaped section having two legs and a connecting portion, further wherein: the air bypass line extends vertically; the connecting portion is located vertically lower than the two legs; and said at least one temperature-dependent resistor is disposed downstream of the connecting portion.
Claim 5
Dependent Claim
81 words
The air flow rate meter apparatus as defined in claim 2, wherein the air bypass line further includes a second U-shaped section disposed adjacent the first U-shaped section, the second U-shaped section having two legs and a connecting portion, further wherein: both U-shaped sections having a common leg; said at least one temperature-dependent resistor is disposed in said common leg; The connecting portion of the first U-shaped section being located vertically lower than the connecting portion of the second U-shaped section.
Claim 6
Dependent Claim
90 words
The air flow rate meter apparatus as defined in claim 2 wherein the air bypass line further includes a second U-shaped section disposed adjacent the first U-shaped section, the second U-shaped section having two legs and a connecting portion, further wherein: said at least one temperature-dependent resistor is disposed in the connecting portion of the second U-shaped section, which is located downstream relative to said first U-shaped section; and the connecting portion of the first U-shaped section being located vertically lower than the connecting portion of the second U-shaped section.
Claim 7
Dependent Claim
159 words
An air flow rate meter apparatus, comprising: an air flow conduit having a restriction; an air bypass line through which air flows which is at a predetermined proportion with respect to the mass of air flowing through the air flow conduit; an air flow rate meter device disposed within the air bypass line, said air flow rate meter device including at least one temperature-dependent resistor, wherein: at least one of temperature and resistance of said at least one temperature-dependent resistor is regulated in accordance with the mass of flowing air; the air bypass line includes a mouth which opens into the air flow conduit at its restriction, and is embodied such that, at least under predetermined operating conditions, a flow of air through the air bypass line mouth toward said at least one temperature-dependent resistor is prevented, and said air bypass line extends vertically such that its end opposite to said mouth is located vertically lower than said mouth.
Claim 8
Dependent Claim
159 words
An air flow rate meter apparatus, comprising: an air flow conduit having a restriction; an air bypass line through which air flows which is at a predetermined proportion with respect to the mass of air flowing through the air flow conduit; an air flow rate meter device disposed within the air bypass line, said air flow rate meter device including at least one temperature-dependent resistor, wherein: at least one of temperature and resistance of said at least one temperature-dependent resistor is regulated in accordance with the mass of flowing air; the air bypass line includes a mouth which opens into the air flow conduit at its restriction, and is embodied such that, at least under predetermined operating conditions, a flow of air through the air bypass line mouth toward said at least one temperature-dependent resistor is prevented, and said air bypass line extends vertically such that its end opposite to said mouth is located vertically lower than said mouth.
References Cited (Backward Citations)
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1987-05-01 | 1987-10-31 | 1988-05-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1991-05-01 | 1991-10-31 | 1992-05-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1995-05-01 | 1995-10-31 | 1996-05-01 | $7700.00 | Window Closed / Lapsed |