Abstract: In a system for delivering secondary air from an air pump to either the exhaust manifold, preferably, closely adjacent to the exhaust ports, or to a converter in the exhaust system of an internal combustion engine, an integral air switching diverter valve assembly having an inlet connected to the air pump, a primary discharge outlet for delivery of air to the exhaust manifold and a secondary discharge outlet for delivery of air to the converter, a valve being mounted in the assembly for movement between a first or converter mode position at which it is normally positioned to allow secondary air flow to the converter while blocking secondary air flow to the exhaust manifold and a second or port mode position to allow secondary air flow to the exhaust manifold while blocking air flow to the converter, the assembly including a differential pressure operated switching diaphragm assembly used to effect movement of the valve between the port and converter modes, a divert timing assembly operative during deceleratio

Abstract: An exhaust cleaning system for use with an automotive multiple-cylinder internal combustion engine including first and second groups of engine cylinders which are to be alternately fired, comprising a thermal reactor composed of an outer tubular structure formed with a first group of exhaust inlet ports leading from the first group of engine cylinders and a second group of exhaust inlet ports leading from the second group of engine cylinders, an inner tubular structure positioned within the outer tubular structure and formed with openings, and at least one air-injection nozzle opening in a longitudinal end portion of the interior or a re-combustion chamber of the inner tubular structure, wherein exhaust gases from each of the first group of engine cylinder are fired in the vicinity of the nozzle openings with the agency of secondary air injected from the nozzle and exhaust gases from each of the second group of engine cylinders are fired by the resultant hot gases advancing through a hot zone of the re-combus

Abstract: Herein disclosed in an exhaust gas cleaning system for an internal combustion engine. The cleaning system comprises a change-over valve having its inlet port communicating with an air pump, its first outlet port communicating with the exhaust system of the engine and its second outlet port communicating with the intake system of the engine through a flow control valve. The change-over valve has communication of its outlet ports switched in accordance with the temperature of a catalytic converter which is disposed in the exhaust system.In a modification, a duct providing communication between the second outlet port of the change-over valve and the flow control valve is provided to communicate with the exhaust system.

Abstract: An apparatus for afterburning the combustible pollutants from the exhaust gases of an internal combustion engine in a reactor, in which secondary air is introduced. Upstream of the reactor, a chamber in the form of a torus is provided, through which the exhaust gases from a maximum number of cylinders flow before entering the reactor. A first obstacle, acting as a flame holder is disposed inside the torus. The reactor comprises a chamber whose inner surface is approximately a surface of revolution, and mounted inside of which is a second obstacle, acting as flame holder, substantially along the axis of revolution. The second flame holder has a diameter large enough to provide a contact time of 1 to 3 .times. 10.sup.-.sup.3 seconds of the gas flow in a recirculation zone surrounding the second flame holder, the diameter of the second flame holder being 15 to 40% of the reactor diameter.

Abstract: An elongate outer hollow member encloses an elongate inner hollow member to form an annular passage therebetween which communicates with an exhaust gas inlet of the outer hollow member. The inner hollow member has a combustion chamber defined therein, a plurality of ports formed through a closed upstream end portion and opening from the exhaust gas inlet into the combustion chamber for injection of a portion of exhaust gas thereinto and a plurality of ports formed through a side portion and opening from the annular passage into the combustion chamber for injection of the remaining portion of exhaust gas thereinto. An secondary air injection means is disposed in the combustion chamber adjacent to the closed end portion and upstream of the ports in the side portion for injection of secondary air into the combustion chamber.

Abstract: A method of purifying exhaust gases of an internal combustion engine by a manifold reactor, wherein secondary air is dividedly supplied at first and second stages especially in a cold starting or accelerating condition of the engine, to burn combustible components in a stepwise manner while avoiding too much cooling of the exhaust gases before the recombustion of the combustible components takes place. This method is effected by a two-staged secondary air supply port structure operated by a control system which responds to operational conditions of the engine.

Abstract: Air is pumped into the engine exhaust manifold to promote oxidation of unburned remnants in exhaust gas when the temperature in a catalytic converter is below a safe level. The air supply to the exhaust manifold is shut off and air is pumped into the catalytic converter to cool it if the temperature goes above the safe level. The catalytic converter includes a catalytic means, having an outer periphery, which is resiliently supported away from the inner circumference of the converter casing. Upon the catalytic means reaching a predetermined maximum temperature, air is pumped into the annular space located between the outer periphery of the catalytic means, which may comprise either a particulate or a monolithic catalyst, and the inner circumference of the casing.

Abstract: An air control valve for directing the flow of air from an internal combustion engine driven pump and including differential pressure actuating means includes a pilot valve responsive to engine induction vacuum level to provide induction vacuum, atmospheric air or air from the pump to the actuating means. The pilot valve includes a chamber having openings communicating with the pump and the actuating means, a restricted orifice to atmosphere, a valve element capable of selectively closing either of the openings, a differential pressure motor actuated by induction vacuum and a tube projecting through the actuating means opening into the chamber, the tube being axially positionable by and in communication with the differential pressure motor to co-act with the valve member and openings to supply high pressure air, atmospheric air or induction vacuum to the actuating means according to the level of induction vacuum.

Abstract: A plurality of pump elements is progressively increasing the pressure of air to respectively supply air at various pressures into portions in an exhaust gas purifying system requiring secondary air.

Abstract: Reaction heat generated by oxidation in presence of an oxidation catalyst maintains a sufficient after-burning temperature during low engine load operation.

Abstract: An air-pollution preventive arrangement for use with an internal combustion engine for motor vehicles, adapted to reduce the concentrations of noxious compounds such as unburned hydrocarbons and carbonmonoxides contained in the engine exhaust gases. The arrangement comprises a thermal reactor for primarily re-combusting the exhaust gases and a catalytic converter for secondarily recombusting the exhaust gases passed from the thermal reactor so as to oxidize the residual unburned compounds. An air injection unit supplies additional air which is admixed, in a limited proportion, to the exhaust gases entering the thermal reactor to aid in the primary re-combustion of the exhaust gases therein. The noxious unconsumed hydrocarbons and carbon-monoxides are thus converted into innocuous compounds at efficiencies which are far higher than those attained where the thermal reactor or the catalytic converter is employed independently.