A carbureting type fuel metering apparatus has an induction passage into which fuel is fed by several fuel metering systems among which are a main fuel metering system and an idle fuel metering system, as generally known in the art; engine exhaust gas analyzing means sensitive to selected constituents of such exhaust gas creates feedback signal means which through associated transducer means become effective for controllably modulating the metering characteristics of the main fuel metering system and the idle fuel metering system.

Apparatus and system for controlling the air-fuel ratio supplied to a combustion engine

Apparatus and method for the protection of an exhaust gas reactor, for example a catalytic element or a thermal reactor, disposed in the exhaust conduit of an internal combustion engine which is operated on a lean air/fuel mixture. This invention provides means for protection of the exhaust gas reactor from excessive temperatures under deceleration conditions by regulating the air/fuel mixture ratio in the induction means of the engine whereby to restrict the oxidation which occurs at the reactor. One method according to the invention comprises adding supplementary air to the induction means for a limited time after the throttle is closed under deceleration conditions, and after an initial delay, adding supplementary fuel to the induction means while the engine continues to operate under deceleration conditions. In addition, thermally sensitive means responsive to the temperature of the exhaust gas reactor serves to maintain the air/fuel ratio of the mixture in the induction means at a relatively richer value whenever there is indication of overheating of the exhaust gas reactor.

Apparatus and method relating to internal combustion engines utilizing an exhaust gas reactor

The temperature of an engine exhaust gas treating device is maintained above a first predetermined value, above which the treating device can purify engine exhaust gases, by interrupting to control an air-fuel ratio of an air-fuel mixture burned in the engine to a desired value and having a mixture forming device form a rich air-fuel mixture, and further by providing a spark in the treating device, retarding the engine ignition timing and/or supplying secondary air into the engine exhaust gases when the treating device temperature is less than the predetermined value, and by resuming to control the air-fuel ratio to the desired value when the treating device temperature is higher than the predetermined value, and below a second predetermined value, below which the treating device is prevented from being damaged by heat, by stopping production of the spark and supply of the secondary air and restoring the engine ignition timing to a normal condition when the treating device temperature is higher than the second predetermined value.

Exhaust gas reaction control system

An exhaust gas purifying system for use in an internal combustion engine for controlling the air injection into an exhaust manifold and the circulation of exhaust gases from the exhaust manifold to a suction pipe, due to a negative pressure prevailing in the suction pipe, in which the negative pressure varies depending on the running conditions of the engine.

Exhaust gas purifying system for use in internal combustion engine

During operation of an internal combustion engine at low temperatures, the carburetor choke is closed to the extent necessary to provide the fuel which will maintain the mean effective pressure of combustion equal to the mean effective pressure occurring during operation at normal temperatures. The torque produced during low temperature engine operation is thus maintained equal to the torque produced during operation at normal temperatures.

Engine control method

A method and apparatus for reducing noxious and harmful compounds contained in exhaust emitted from a gasoline powered internal combustion engine. The method comprising the steps of detecting the temperature of an exhaust gas treating device provided in the engine or the temperature of the exhaust gases passing through the exhaust gas treating device, and controlling the air-fuel ratio of an air-fuel mixture to be supplied to the engine in accordance with the variations in the temperature of the exhaust gas treating device or the temperature of the exhaust gases therein so as to maintain the exhaust gas treating device at its optimum performance efficiency. In one preferred embodiment, the apparatus is arranged to utilize a choke valve disposed in a carburetor of the engine for controlling the airfuel ratio of the air-fuel mixture to be supplied to the engine in accordance with the variations in the temperature of the exhaust gas treating device or the temperature of the exhaust gases therein. In another preferred embodiment, the appratus is arranged to utilize a power valve assembly provided in the carburetor of the engine for controlling the air-fuel ratio of the air-fuel mixture to be supplied to the engine in dependence on the variations in the temperature of the exhaust gas treating device or the temperature of the exhaust gases therein.

K Masaki

Papers

Method and apparatus for reducing toxic compounds in exhaust gases from internal combustion engine