Patent US4267732A successfully refreshed from Google Patents.
Patent EP0268433A1 successfully refreshed from Google Patents.
EP0268433A1
Expired / Lapsed
EP
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Method of controlling an air/fuel ratio for an internal combustion engine
Assignee: Honda Motor Co Ltd
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Filing: 1987-11-12
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Granted: —
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Expires: 2007-11-12
Abstract
Abstract A method for controlling the air/fuel ratio of the intake air mixture supplied to an internal combustion engine having multiple cylinders and a valve operating mechanism for switching the magnitude of the intake valve openings for low and high speed operation. The method includes the step of providing a lean air/fuel ratio at low speeds and the step of gradually varying the air/fuel ratio of a range of engine speeds that include the speed at which the valve operation is switched to avoid any possible abrupt change in engine output upon switching the valve operation.
Inventors
- 👤 Noriyuki Kishi
- 👤 Atsushi Katoh
- 👤 Tomohisa Saita
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-01 20:40
CPC Classifications
F; F02; F02D; F02D13/00; F02D13/02; F02D13/0203; F02B; F02B31/00; F02D13/0257; F02D41/00; F02D41/0002; F02D2041/001; Y; Y02; Y02T; Y02T10/00; Y02T10/10; Y02T10/12; Y02T10/40
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
69 words
A method of controlling an air/fuel ratio for an internal combustion engine having a valve switching device for changing the characteristics of an intake valve operation as a function of at least engine rotational speed, comprising: gradually varying the air/fuel ratio according to at least a change in said engine rotational speed in a range of rotational speeds including when said valve switching device effects a valve switching operation.
Claim 2
Independent Claim
69 words
A method of controlling an air/fuel ratio for an internal combustion engine having a valve switching device for changing the characteristics of an intake valve operation as a function of at least engine rotational speed, comprising: gradually varying the air/fuel ratio according to at least a change in said engine rotational speed in a range of rotational speeds including when said valve switching device effects a valve switching operation.
Claim 3
Dependent Claim
49 words
A method according to claim 1, including the steps of opening and closing the intake valves in a manner for maximizing the flow of intake air in a high engine rotational speed range and for relatively restricting the flow of intake air in a low engine rotational speed range.
Claim 4
Dependent Claim
37 words
A method according to claim 1 or 2, including the step of controlling the air/fuel ratio to be relatively lean in said low engine rotational speed range and relatively rich in said high engine rotational speed range.
Claim 5
Independent Claim
32 words
A method according to claims 1, 2 or 3 including the step of starting the gradual varying of the air/fuel ratio before reaching the rotational speed at which the valve switching occurs.
Claim 6
Independent Claim
29 words
A method according to any preceding claim, including the step of continuing said gradual varying of the air/fuel ratio beyond the rotational speed at which the valve switching occurs.
Claim 7
Dependent Claim
39 words
A method according to claim 5 including the step of continuing said gradual varying the air/fuel ratio over a substantial range of rotational speed below the rotational speed at which the valves switching occurs during engine speed decreasing operation.
Claim 8
Independent Claim
37 words
A method according to any preceding claim, including the step of causing the operation of the valve switching device to occur at a higher rotational speed during engine speed increasing operation than during engine speed decreasing operation.
Claim 9
Dependent Claim
39 words
A method according to claim 7, wherein the difference in rotational speed between valve switching device operation during engine speed increasing and decreasing operation is relatively constant over all ranges of opening of a throttle valve for the engine.
References Cited (Backward Citations)
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