US3827414A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Exhaust recirculation
Assignee: Old Carco LLC
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Filing: 1972-09-21
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Granted: 1974-08-06
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Expires: 1992-09-21
Abstract
Abstract Automobile engine exhaust gases are recycled through a recycling duct having a restricted upstream end opening into the exhaust system and first and second restricted downstream ends opening into the carburetor inlet induction conduit downstream and upstream respectively of the throttle valve. The restrictions for the recycling duct are dimensioned with respect to each other so that when the throttle valve is at its closed or idle position, a major quantity of the air required to support engine combustion at idle will bypass the throttle valve and flow through the portion of the recycling duct from the second downstream end to the first. The second restricted downstream end opens into the induction conduit at the usual fuel metering venturi restriction and is restricted appreciably less than the first downstream end, such that when the throttle valve is opened from the idle position, the first downstream end will have only a minor influence on the pressure in the recycling duct and the exhaust gas flow thereinto from the exhaust conduit via the restricted upstream end will be substantially a function of the pressure differential between the exhaust pressure at the upstream end and the venturi pressure at the second downstream end. The induction conduit pressure immediately upstream of the upstream leading edge of the blade of the throttle valve, when the latter is at its idle position, is employed to operate a valve to close the recycling duct completely at a location upstream of the two downstream ends during both idle and wide open throttle operation of the engine.
Inventors
- 👤 J Sarto
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-26 19:46
CPC Classifications
F; F02; F02M; F02M26/00; F02M26/52; F02M26/59; F02M26/60; F02M26/13; F02M26/36; F02M26/55; F02M26/17; F02M26/21
Claims Analysis
Total Claims: 24
Claim 1
Independent Claim
186 words
In an internal combustion engine, an inlet header for conducting a combustible fuel-air mixture into said engine and having 1. a venturi restriction therein and 2. a throttle valve therein downstream of said vEnturi restriction and movable to idle and open positions for controlling fluid flow therethrough, an exhaust header for discharging combustion products from said engine, and means for recycling exhaust gases from said exhaust header to said inlet header as a function of the rate of fluid flow through said inlet header to inhibit the formation of nitrogen oxides during combustion comprising recycling duct means having 1. a restricted upstream opening communicating with said exhaust header to receive exhaust gases, and 2. first and second restricted downstream openings communicating with said inlet header in parallelism with each other at locations downstream and upstream respectively of said throttle valve to discharge said exhaust gases into said inlet header, 3. the sizes of the restrictions for said openings being in predetermined relationship with respect to each other and said second downstream opening communicating with said inlet header at a restricted region thereof comprising said venturi restriction.
Claim 2
Dependent Claim
186 words
In an internal combustion engine, an inlet header for conducting a combustible fuel-air mixture into said engine and having 1. a venturi restriction therein and 2. a throttle valve therein downstream of said vEnturi restriction and movable to idle and open positions for controlling fluid flow therethrough, an exhaust header for discharging combustion products from said engine, and means for recycling exhaust gases from said exhaust header to said inlet header as a function of the rate of fluid flow through said inlet header to inhibit the formation of nitrogen oxides during combustion comprising recycling duct means having 1. a restricted upstream opening communicating with said exhaust header to receive exhaust gases, and 2. first and second restricted downstream openings communicating with said inlet header in parallelism with each other at locations downstream and upstream respectively of said throttle valve to discharge said exhaust gases into said inlet header, 3. the sizes of the restrictions for said openings being in predetermined relationship with respect to each other and said second downstream opening communicating with said inlet header at a restricted region thereof comprising said venturi restriction.
Claim 3
Dependent Claim
35 words
first and second restricted downstream openings communicating with said inlet header in parallelism with each other at locations downstream and upstream respectively of said throttle valve to discharge said exhaust gases into said inlet header,
Claim 4
Dependent Claim
35 words
first and second restricted downstream openings communicating with said inlet header in parallelism with each other at locations downstream and upstream respectively of said throttle valve to discharge said exhaust gases into said inlet header,
Claim 5
Dependent Claim
72 words
a throttle valve therein downstream of said vEnturi restriction and movable to idle and open positions for controlling fluid flow therethrough, an exhaust header for discharging combustion products from said engine, and means for recycling exhaust gases from said exhaust header to said inlet header as a function of the rate of fluid flow through said inlet header to inhibit the formation of nitrogen oxides during combustion comprising recycling duct means having
Claim 6
Dependent Claim
72 words
a throttle valve therein downstream of said vEnturi restriction and movable to idle and open positions for controlling fluid flow therethrough, an exhaust header for discharging combustion products from said engine, and means for recycling exhaust gases from said exhaust header to said inlet header as a function of the rate of fluid flow through said inlet header to inhibit the formation of nitrogen oxides during combustion comprising recycling duct means having
Claim 7
Dependent Claim
51 words
In the combination according to claim 1, said exhaust header having a wall portion extending transversely to the flow of said fuel-air mixture in said inlet header to provide a hot wall for impingement of said mixture thereagainst, said first downstream opening extending through said hot wall in heat transfer relationship.
Claim 8
Dependent Claim
36 words
the sizes of the restrictions for said openings being in predetermined relationship with respect to each other and said second downstream opening communicating with said inlet header at a restricted region thereof comprising said venturi restriction.
Claim 9
Dependent Claim
36 words
the sizes of the restrictions for said openings being in predetermined relationship with respect to each other and said second downstream opening communicating with said inlet header at a restricted region thereof comprising said venturi restriction.
Claim 10
Dependent Claim
29 words
In the combination according to claim 2, said first downstream opening being directed in opposition to the flow of said fuel-air mixture at the region of said hot wall.
Claim 11
Dependent Claim
50 words
In the combination according to claim 1, said first downstream opening being smaller than said upstream opening and being dimensioned to provide a flow of inlet air bypassing said throttle amounting to the major portion of the idle combustion supporting air when said throttle valve is at its idle position.
Claim 12
Dependent Claim
25 words
In the combination according to claim 4, said second downstream opening being between approximately 4 and 10 times as large as said first downstream opening.
Claim 13
Dependent Claim
51 words
In the combination according to claim 5, said exhaust header having a wall portion extending transversely to the flow of said fuel-air mixture in said inlet header to provide a hot wall for impingement of said mixture thereagainst, said first downstream opening extending through said hot wall in heat transfer relationship.
Claim 14
Dependent Claim
25 words
In the combination according to claim 1, said second downstream opening being between approximately 4 and 10 times as large as said first downstream opening.
Claim 15
Dependent Claim
92 words
In the combination according to claim 1, the cross sectional areas of the restrictions for each of said upstream and second downstream openings being sufficiently large with respect to the cross sectional area of said first downstream opening to maintain a flow of exhaust gases through said upstream opening determined approximately by the pressure differential between the exhaust pressure in said exhaust header and the venturi pressure in said inlet header at the region of said second downstream opening when said throttle valve is opened a predetermined extent from said idle position.
Claim 16
Dependent Claim
28 words
In the combination according to claim 8, the cross sectional area of said second downstream opening being several times the cross sectional area of said first downstream opening.
Claim 17
Dependent Claim
38 words
In the combination according to claim 9, said first downstream opening being dimensioned to pass between approximately 50 percent and 80 percent of the air required for idle combustion when said throttle valve is at its idle position.
Claim 18
Dependent Claim
20 words
In the combination according to claim 10, said second downstream opening between located at the diffuser region of said venturi.
Claim 19
Dependent Claim
60 words
In the combination according to claim 1, said first restricted downstream opening of said recycling duct means into said inlet header comprising a throttle bypass system for idle air during idle operation of said engine, and valve means responsive to said idle operation for closing said recycling duct means at a location between Said upstream restriction and said downstream restriction.
Claim 20
Dependent Claim
50 words
In the combination according to claim 12, said first downstream opening being smaller than said upstream opening and being dimensioned to provide a flow of inlet air bypassing said throttle amounting to the major portion of the idle combustion supporting air when said throttle valve is at its idle position.
Claim 21
Dependent Claim
25 words
In the combination according to claim 13, said second downstream opening being between approximately 4 and 10 times as large as said first downstream opening.
Claim 22
Dependent Claim
52 words
In the combination according to claim 12, the cross sectional area of said second downstream opening being several times larger than the cross sectional area of said first downstream opening, and means responsive to wide open throttle operation for operating said valve means to close said recycling duct means at said location.
Claim 23
Dependent Claim
112 words
In the combination according to claim 15, said valve means and means responsive to said wide open throttle operation comprising a recycling valve movable between open and closed positions to open or close respectively the communication between said upstream opening and said downstream openings at said location, and means responsive to the pressure in said inlet header upstream of said throttle valve when the latter is at its idle position for moving said recycling valve to its closed position when the last named pressure exceeds a predetermined pressure and for moving said recycling valve to its open position when said last named pressure is not greater than the first named predetermined pressure.
Claim 24
Dependent Claim
85 words
In the combination according to claim 16, said throttle valve comprising a blade type valve having an upstream leading edge, said means responsive to the pressure in said inlet header at a location upstream of said throttle valve comprising pressure responsive means in communication with said inlet header at a location adjacent and upstream of said leading edge when said throttle valve is at its idle position, said location being downstream of said leading edge when said throttle valve is opened to a predetermined position.
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) | 1977-08-05 | 1978-02-04 | 1978-08-06 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1981-08-05 | 1982-02-04 | 1982-08-06 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1985-08-05 | 1986-02-04 | 1986-08-06 | $7700.00 | Window Closed / Lapsed |