Abstract: Methods and systems are provided for re-combustion of exhaust in a cylinder of a multi-cylinder engine in order to increase the temperature of the exhaust for enhancing catalytic conversion within the multi-cylinder engine. In one example, a method may include expelling combusted gases from the cylinder into an intake manifold via an intake valve during an exhaust stroke, in order to rebreathe in the combusted gases from the intake manifold via the intake valve in a subsequent intake stroke.

Abstract: Engine systems and methods use a dual air injection approach to control exhaust reactions and to maintain temperatures below a maximum limit of exhaust system components during engine enrichment operation conditions. Dual air injectors are disposed in the exhaust system with one upstream from, and another downstream from, the catalytic converter. Providing air injection before and/or after the converter helps convert all HC, CO, and PM emissions while keeping the catalyst temperature below the catalyst protection temperature limit. Air injection quantity may be controlled and diagnosed by monitoring the temperatures before and after the catalytic converter. The catalytic converter may be a three-way catalytic converter for lower cost or a downstream two-way catalytic converter may be added if further emission reduction is necessary.

Abstract: An engine brake controller may obtain a performance characteristic of an engine. The engine brake controller may determine, based on the performance characteristic of the engine, that engine braking is enabled to control the engine. The engine brake controller may monitor a set of operating parameters of the engine. The engine brake controller may determine that operating values of the set of operating parameters satisfy corresponding thresholds of the set of operating parameters. The engine brake controller may determine, based on the operating values satisfying the corresponding thresholds, an engine braking configuration associated with activating engine braking of a set of cylinders of the engine. The set of cylinders may be a proper subset of a total quantity of cylinders of the engine. The engine brake controller may cause the engine braking to be applied to the set of cylinders to increase a temperature of exhaust gas from the engine.

Abstract: Three-port latching valves have a housing with a first port, a second port, and a third port in controlled fluid communication with one another by three, individually electronically controllable magnetically latching valves for a combination of five different flow options. Each valve has a solenoid with an armature movable between an open position and a closed position, a poppet valve connected to the armature, a permanent magnet fixedly seated at a position for magnetically latching the armature in the open position, and a spring positioned to bias the poppet valve closed when the armature is in the closed position. The spring has a pre-selected spring rate that mechanically relieves pressure if the spring rate is exceeded. The armature is movable to the open position after a pulse of voltage to the solenoid and is in an unpowered state after translation to either of the open position or the closed position.

Abstract: A reed valve is adapted to be fixed to a fixing member. The reed valve includes a valve plate and a resiliently deformable reed. The valve plate is fixed to the fixing member and includes a frame part and a supporting column. The frame part has an opening inward of the frame part. The opening passes through the frame part in a thickness direction of the valve plate. The supporting column is disposed across an inside of the opening. The reed is configured to open or close the opening. The frame part includes a frame seating surface with which the reed is engaged. The supporting column includes a column seating surface with which the reed is engaged. The column seating surface is recessed relative to the frame seating surface in the thickness direction.

Abstract: A secondary air injection or SAIR system is illustrated and described which includes a first air injection path defined by in part by a lower ditch formed in the head mounting surface of the cylinder block, and a second air injection path defined in part by a second ditch formed in the block mounting surface. The cylinder head gasket is used to separate and seal the first ditch from the second ditch. The first and second air injection paths are separate and isolated from one another such that secondary air may be selectively introduced through the first air injection path into the first exhaust leg and selective introduced through the second injection path into the second exhaust leg independent of the first air injection path.

Abstract: A method for operating a spark-ignition engine having a three-way catalyst and a particulate filter downstream thereof, comprising: oscillating an exhaust air-fuel ratio entering the particulate filter to generate air-fuel ratio oscillations downstream of the particulate filter, while increasing exhaust temperature; when the downstream oscillations are sufficiently dissipated, enleaning the exhaust air-fuel ratio entering the particulate filter; and reducing the enleanment when an exhaust operating parameter is beyond a threshold amount.

Abstract: An aftertreatment module for use with an engine is disclosed. The aftertreatment module may have a first chamber with an inlet, and at least one catalyst substrate disposed in the first chamber in a flow path through the inlet and having a flow direction from an inlet face to an outlet face in general alignment with the flow path. The aftertreatment module may also have a second chamber with at least one outlet in general alignment with the flow direction through the inlet. The aftertreatment module may further have at least one noise attenuation passage fluidly connecting the first chamber with the second chamber. The at least one noise attenuation passage may be oriented generally orthogonal to the inlet and the at least one outlet and be located between the inlet and the outlet face of the at least one catalyst substrate.

Abstract: In an exhaust emission control system for an internal combustion engine, an exhaust gas recirculation device that operates so as to partially open an exhaust valve to introduce exhaust gas into a cylinder in an intake stroke is provided; a secondary air passage capable of supplying secondary air to an exhaust passage is connected to the exhaust passage; and a one-way valve opened by negative pressure applied from the cylinder to the exhaust passage following an operation of the exhaust gas recirculation device in the intake stroke is provided in the secondary air passage. Accordingly, it is possible to provide an exhaust emission control system for an internal combustion engine that allows secondary air to be supplied into an exhaust passage to reduce HC and CO concentrations and also a NOx concentration in an exhaust gas without using an air pump regardless of an exhaust system structure of the internal combustion engine.

Abstract: This invention is to provide a tappet clearance adjusting cover coupled with a secondary air valve. The tappet clearance adjusting cover is disposed on a cylinder head of an engine. The secondary air valve includes a recessed element and a cap which jointly form a receiving space receiving therein a one-way valve. The recessed element is provided with an inlet pipe interposed between the cap and the tappet clearance adjusting cover. By disposing the secondary air valve on the tappet clearance adjusting cover and arranging the inlet pipe between the cap and the tappet clearance adjusting cover, with the one-way valve received in the receiving space of the secondary air valve, heat dissipation can be improved while the one-way valve is protected against premature deterioration and carbon deposition caused by a high-temperature exhaust gas from the cylinder head. Thus, reliability as well as a service life of the one-way valve is effectively increased.

Abstract: A secondary-air supply system for an internal combustion engine, including a catalyst provided in an exhaust passage and configured to purify exhaust gas from the engine, and a secondary-air supply source and a secondary-air valve provided in a secondary-air passage connected upstream from the catalyst. A secondary-air supply device is configured to drive the secondary-air supply source and to open the secondary-air valve to supply secondary air to the exhaust passage upstream from the catalyst under a warm-up condition of the engine. Secondary-air supply control means is configured to control the secondary-air supply device to drive the secondary-air supply source and to open the secondary-air valve under a high-load operating condition where a flow rate of the exhaust gas is high, the high-load operating condition being different from the warm-up condition.

Abstract: An exhaust-pipe structure for a saddle-ride type vehicle includes expansion paths each having a capacity appropriate for the output capacity of a corresponding cylinder. A front exhaust pipe and a rear exhaust pipe extend from a front cylinder and a rear cylinder constituting a V-type engine, respectively. A silencer is connected to rear end portions of the front and rear exhaust pipes. As expansion chambers, the silencer is provided with a lower first chamber led from the front cylinder and an upper first chamber led from the rear cylinder. A protruding space protruding from the lower first chamber is formed so that the capacity of the lower first chamber led from the front cylinder is larger than the capacity of the upper first chamber led from the rear cylinder.

Abstract: A secondary air supply system includes a CPU, a ROM, an air supply pipe, and an air amount adjusting valve. One end of the air supply pipe is connected to an air cleaner box and the other end is connected to an exhaust port. Secondary air in the air cleaner box is supplied to the exhaust port through the air supply pipe. An amount of the secondary air to be supplied from the air supply pipe to the exhaust port is adjusted by the air amount adjusting valve. A target air-fuel ratio depending on a state of the engine is stored in the ROM. The CPU controls the air amount adjusting valve based on the state of the engine so that an air-fuel ratio in the exhaust port is the target air-fuel ratio.

Abstract: An exhaust filter system includes a particulate filter (PF) that is disposed downstream from an engine. The PF filters particulates within an exhaust from the engine. A heating element heats particulate matter in the PF. A fastener limits expansion movement of the heating element relative to the PF.

Abstract: An exhaust system includes a particulate filter (PF) that is disposed downstream from an engine. The PF filters particulates within an exhaust from the engine. A heating element heats particulate matter in the PF. A catalyst substrate or a flow converter is disposed upstream from said heating element. The catalyst substrate oxidizes the exhaust prior to reception by the heating element. The flow converter converts turbulent exhaust flow to laminar exhaust flow prior to reception by the heating element.

Abstract: A method of reducing NOx in a lean burn engine exhaust stream from a hydrocarbon burning engine may be first passing the exhaust stream over a thrifted diesel oxidation catalyst that substantially completes the oxidation of carbon monoxide to carbon dioxide and the oxidation of hydrocarbons (HC) to carbon dioxide and water. Next, separate additions of ozone and ammonia or urea may be introduced to the exhaust gas stream upstream of the catalytic reduction reactor at temperatures below 250 degrees Celsius. The additions of ozone and ammonia or urea modify the exhaust gas composition to improve the performance of NOx reduction catalysts in the catalytic reduction reactor. At temperatures above 250 degrees, the ozone addition may be reduced or eliminated, while the ammonia addition can be controlled as a function of the amount of NOx in the exhaust stream and the temperature of the catalytic reduction reactor.

Abstract: In a secondary air supplying structure of an internal combustion engine, extending portions protruding upward are arranged in the number corresponding to the number of cylinders. Extending portions are each provided with a secondary air distribution path. To a surface of extending portion to which secondary air supplying pipe abuts, a seating face that conforms to the outer shape of secondary air supplying pipe is formed. Secondary air distributing path is arranged to be inclined downwardly from secondary air supplying pipe side toward the cylinder exhaust system of cylinder head. Thus, it is possible to provide the secondary air supplying structure of an internal combustion engine that can attain an improvement in the strength of the secondary air supplying path, reduction of the space, rust prevention, reduced costs, reduced weight, simplified structure, and prevention of thermal damage to other components.

Abstract: The gas-dynamic pressure wave machine is intended for supplying charge air to an internal combustion engine and comprises a rotor (40) with cells (41), a low pressure fresh air inlet channel, a high pressure charge air channel leading to the internal combustion engine, a high pressure exhaust gas channel (31) coming from the internal combustion engine, and a low pressure exhaust gas channel (35), the low pressure exhaust gas channel (35) and the high pressure exhaust gas channel (31) being enclosed in a gas enclosure (34), and the low pressure fresh air inlet channel and the high pressure charge air channel being enclosed in an air enclosure, and the high pressure exhaust gas channel being provided on the rotor side with a widened portion (53).

Abstract: An apparatus and method for reducing pollutants in engine exhaust through the use of pulsed engine compression braking. The apparatus includes a controller, a number of engine sensors connected to the controller, and connections from the controller to the exhaust valves. Bases on data from the engine sensors, the invention opens the exhaust valves during either the compression stroke, the exhaust stroke, or both. Hot fuel mixture or hot gases are then injected into the exhaust manifold, where they burn pollutants. Optionally, pressurized air can be injected into the exhaust manifold to assist in burning pollutants.

Abstract: The present invention relates to a method and a corresponding system for catalytic aftertreatment of the exhaust gas of an internal-combustion engine. Two spatially separate catalyst devices are provided in the exhaust gas system. The first of these catalyst devices is arranged in a position close to the engine, and the second catalyst device is arranged in a position away from the engine. An exothermal reaction is caused to take place during warm-up for heating the second catalyst device.

Abstract: An exhaust manifold device is provided to allow air to enter an exhaust manifold during normal operation or an engine to prevent exhaust gases being sucked into the cylinders via exhaust valves. Air can be supplied, via valves (18 and 21) to the exhaust manifold as required and, is supplied to the valve (21) at pressures, above atmospheric pressure, that increase with engine speed. Synchronized electrical pulses are supplied to a solenoid (18A) to open the valve (18).

Abstract: To provide an apparatus for feeding secondary air to exhaust gas in an engine. The apparatus includes a cylinder head having an exhaust port for discharging exhaust gas from a combustion chamber and a secondary air feed passage for feeding secondary air to exhaust gas flowing through the exhaust port. The apparatus is capable of making a length of the secondary air feed passage as short as possible while preventing the permeation of exhaust gas into the secondary air feed passage. This avoids the enlargement of the entire engine, when disposing a reed valve in the engine, since the reed valve is mounted to the cylinder block. A secondary air passage includes a first passage portion extending in a straight line with one end opened toward the inner surface of an exhaust port, toward the downstream side of exhaust gas in the flowing direction.

Abstract: An exhaust purifier of an internal combustion engine supplies secondary air into an exhaust pipe without cooling nor inactivating an electrically heated catalyst (EHC) that is active. The exhaust purifier includes the EHC 3 disposed in the exhaust pipe 2, a main catalyst 4 disposed in the exhaust pipe 2 downstream from the EHC 3, and a unit for supplying secondary air into the exhaust pipe 2. The secondary air supply unit has a main path 10 for supplying secondary air into a space defined in the exhaust pipe 2 between the EHC 3 and the main catalyst 4 when it is determined that the main catalyst 4 is active. The secondary air supply unit may additionally have a second path 9 for supplying secondary air into the exhaust pipe 2 on the upstream side of the EHC 3 when it is determined that the EHC 3 is active, so that the secondary air may pass through the EHC 3 and reach the main catalyst 4.

Abstract: A thermal reactor for reducing exhaust emissions generated by an engine. The thermal reactor preferably includes an outer housing and an inner core mounted within the outer housing. The inner core defines an expansion chamber which receives exhaust gas from the engine. When the exhaust gas enters the expansion chamber, it expands and becomes thoroughly mixed. While in the expansion chamber, at least some of the exhaust gas is oxidized. A single-layered recirculation chamber is located between the outer housing and the inner core. The recirculation chamber receives the exhaust gas from the expansion chamber and recirculates the exhaust gas around the outer surface of the inner core such that the inner core is insulated. By insulating the inner core with heated exhaust gas from the expansion chamber, the expansion chamber maintains a high temperature which facilitates oxidation of the exhaust gases.

Abstract: An exhaust gas purification device comprising a three way catalyst, an oxidizing catalyst and a NOx absorbent which are arranged in this order in the exhaust passage. A rich air-fuel mixture is burned in the combustion chamber, and the exhaust gas discharged from the engine is initially introduced into the three way catalyst. Secondary air is fed into the exhaust passage between the three way catalyst and the oxidizing catalyst so that the air-fuel ratio of the exhaust gas flowing into the oxidizing catalyst and the NOx absorbent becomes lean.

Abstract: An exhaust-gas recombustion system for recombusting exhaust gases coming out of exhaust ports of an internal combustion engine equipped with a catalytic converter, comprises a plurality of branch pipes of an exhaust manifold connected to the exhaust ports, a plurality of secondary air injection tubes each connected to either one of the branch pipes for recombusting the exhaust gases coming out of the exhaust ports by secondary air injection. An air-injection nozzle of the secondary air injection tube is directed towards the exhaust port communicating with the connected branch pipe along the axial line of the exhaust port. Additionally, the air-injection nozzle is arranged close to a curved wall of the connected branch pipe to effectively sweep away resultant exhaust gases left in the exhaust port and consequently to assure a rapid activation of the catalytic converter during a cold start of the engine.

Abstract: A continuously active pressure accumulator power transfer system for a vehicle or a like comprises an engine, a pump driven by the engine, a main pressure accumulator maintained at a substantially constant fluid pressure and fluid volume by the pump during operation, a fluid motor for propelling the vehicle which is supplied with driving fluid pressure from the pressure accumulator and auxiliary units for operating the vehicle. The auxiliary units are also operated by fluid pressure from the pressure accumulator. The fluid motor(s) and the auxiliary units are operated directly by fluid pressure from the accumulator without any direct connection with the engine.

Abstract: This specification teaches a method for treatment of exhaust gases which if left untreated can generate, upon full oxidation, temperatures in a range of from about 1600.degree. F. to about 2700.degree. F. over an oxidizing catalyst. The method has the following steps. An internal combustion engine (10) is operated under conditions in which there is insufficient oxygen to oxide all the hydrocarbon present in the fuel. The exhaust gases so-developed are passed into an exhaust manifold (12) and then through an exhaust pipe (14) to an oxidation catalyst (16) whose primary oxidation catalyst is palladium. An air pump (20) generates a supply of oxygen which can supply up to about 80% of the oxygen required to combust fully all of the hydrocarbons and carbon monoxide contained in the exhaust gases when the internal combustion engine is operating in a wide-open throttle condition.

Abstract: A pressure control system for use in vehicle emissions control includes an air control valve (12) having a housing (14) defining an inlet (16) communicated to the vehicle air pump and a pair of outlets (18, 20). A primary valve assembly (22) controls communication between the inlet (16) and the outlets (18, 20) and includes a pair of valve members (54, 56) actuated by a differential pressure responsive diaphragm assembly (39). The pressure differential across the diaphragm assembly (39) is controlled by a pressure signal generated from a pressure tap (84) from the inlet (16). A pair of solenoid valves (88, 92) controls communication to the diaphragm assembly and to a pressure responsive relief valve assembly (60) which controls communication between the inlet (16) and an atmospheric vent (78).

Abstract: An air management valve in the exhaust emission control system for the engine of an automotive vehicle is operative to selectively control secondary air flow to the exhaust manifold next adjacent to the exhaust ports of the engine, to the center of a dual bed catalytic converter and to the atmosphere.

Abstract: An exhaust gas purifying system for an automobile engine including at least first and second engine cylinder has a shutter valve for interrupting the supply of a combustible air-fuel mixture to the first engine cylinder during a particular engine operating condition, a three-way electromagnetically operated valve for controlling the operation of the shutter valve, and a secondary air supply unit including a switching valve for selectively supplying a secondary air to a portion of an exhaust passage upstream of at least one catalyst unit disposed in the exhaust passage.

Abstract: An electric air control switching valve for use in controlling the delivery of secondary air from an engine driven air pump selectively, as a function of both engine operation and the operation of its associated emission control system, to either the exhaust manifold of an engine, preferably at a location closely adjacent to the exhaust ports of the engine, during low temperature engine operation, to the atmosphere, as at the dirty side of the air cleaner associated with the induction system of the engine, during low temperature engine deceleration, to a converter in the exhaust system for the engine downstream of the exhaust manifold during normal engine operation, or again to the atmosphere, as at the dirty side of the air cleaner, when the converter temperature exceeds a predetermined temperature.

Abstract: This device results in a very precise metering of the amount of air introduced by a first injector between two catalysts of an exhaust line. To achieve this, first regulating means are regulated so as to deliver a carburetted mixture which is richer than the stoechiometric composition. A second air injector and a second gas analyzer are placed in this order in the exhaust line between a first analyzer and a triple-function catalyst. The second analyzer is associated with second regulating means which control the flow of air in the second injector so as to bring the composition of the exhaust gases to that which would correspond to a richness of the carburetted mixture between the richness regulated by the first regulating means and the stoechiometric composition. Means are provided for maintaining the flows of air of the first and second air injectors proportional to each other.

Abstract: This application discloses a secondary air control system in an internal combustion engine.

Abstract: An electromagnetic valve has a housing with interior side walls defining a deltoid valve chamber with an inlet port opening thereto. Each of the three side walls defining the sides of the valve chamber has a discharge port extending therefrom. Each side wall also has a solenoid coil means associated therewith whereby flow to the respective ports can be controlled by a triangular shaped valve member. The valve member includes a hollow triangular shaped valve carrier having three armature valve elements movably positioned thereon. When any two solenoid coil means are energized, the corresponding valve elements are magnetically attracted to the respective solenoid coil means whereby to block flow out through the two associated ports, the valve carrier moving with these two valve elements effects movement of the remaining valve element to a position whereby to uncover the discharge port associated with the remaining de-energized solenoid coil means.

Abstract: An improved by-pass valve (1) for use in an automobile exhaust system (ES) comprises an air inlet (7) connected to an air pump (AP), first and second air outlets (15,23) respectively connected to first and second portions (P1,P2) of a catalytic converter (CC) and a third outlet (33) through which air is dumped to atmosphere. Air is directed from the inlet to the first outlet when engine temperature is less than a predetermined value and from the inlet to the second outlet when engine temperature reaches the predetermined value. A first and normally closed valve (81) is intermediate the air inlet and the first and second outlets and a second and normally open valve (83) is intermediate the air inlet and the third outlet. The first valve is opened and the second valve closed when engine vacuum exceeds a predetermined level so air flows to either the first or second outlet. The second valve is reopened whenever the outlet to which air is directed is blocked so air is dumped to atmosphere.

Abstract: Apparatus for controlling introduction of gas into a passage of an internal combustion engine employs a first control valve in a gas introduction passageway, a second control valve in an air conduit connecting the intake passage to atmosphere, and a regulating valve responsive to vacuum intensity in the intake passage. The regulating valve actuates vacuum responsive actuators for the control valves. This system is used for recirculating exhaust gases into the intake passage, for introducing supplementary atmospheric air into the intake passage to modifying the air-fuel ratio in accordance with atmospheric pressure reduction at high altitudes, and for controlling the introduction of atmospheric air into the exhaust passage upstream from a catalytic converter or reactor.

Abstract: Disclosed is a double feedback loop type of secondary air control system for an internal combustion engine, in which a valve provided in a secondary air feed passage for regulating a quantity of the secondary air fed into an exhaust passage of the engine is operated in response to a first error signal indicative of a deviation of the actual secondary air quantity from the desired secondary air quantity and a second error signal indicative of a deviation of the actual air-fuel ratio from the desired air-fuel ratio, thereby effecting a precise control of the air-fuel ratio.

Abstract: A sufficient amount of secondary air is supplied to the exhaust gases without requiring numerous supply tubes. The supply tubes are connected to the longest branch of the exhaust manifold or the exhaust port passage to which the longest branch is connected where the inertial flow of the exhaust gases is greatest. A mass of the exhaust gases recirculated to the intake through a recirculation tube is prevented from being admixed with the secondary air. The recirculation tube is connected to the branches of the manifold exclusive of the longest branch.

Abstract: Disclosed is a secondary air supplying device of an internal combustion engine having an exhaust passage provided with a catalyzer for purifying exhaust gas. The device includes a first air injection port provided in the exhaust passage at the upstream side of an exhaust manifold and a second air injection port provided in the exhaust passage at the upstream side of the catalyzer. Under the engine warming operating condition only when the engine speed is abruptly accelerated, or during a predetermined time interval after the engine is warmed, is secondary air injected into the exhaust passage from the second air injection port. When the engine is in the other operating conditions, secondary air is injected into the exhaust passage from the first air injection port.

Abstract: A system for purifying exhaust gases of engines by first passing the exhaust gases through a 3-way catalyst in a reducing condition, and secondly through an auxiliary catalyst which accelerates at least the oxidizing reaction in an oxidizing condition, wherein the reducing and oxidizing conditions of the exhaust gases are controlled by a programmed supply of secondary air to the exhaust gases at the upstream sides of the two catalysts, the program for the supply of secondary air being predetermined depending upon operational conditions of the engine, such as the rotational speed and the intake manifold vaccum of the engine.

Abstract: In a system for delivering secondary air from an air pump selectively, as a function of engine operation, to either the exhaust manifold at a location closely adjacent to the exhaust ports of the engine, or either to a converter in the exhaust system downstream of the exhaust manifold or to the atmosphere, as preselected, an integral air switching diverter valve assembly having an inlet connected to the air pump, a primary outlet for discharge of air to the exhaust manifold and a secondary outlet, for delivery of air either to the converter or to the atmosphere, as preselected, a valve being mounted in the assembly for movement between a first position to which it is normally biased to allow secondary air flow and through the secondary outlet while blocking secondary air flow through the first outlet to the exhaust manifold and a second position to allow secondary air flow to the exhaust manifold while blocking air flow out through the second outlet, the assembly including a differential pressure operated swi

Abstract: Control of secondary air flow to a reactor during normal operating condition of an engine is provided by relieving a predetermined portion of the secondary air discharged from an air pump to a point intermediate the reactor and a muffler installed downstream of the reactor. When the engine is operating under heavy load and/or at high speeds, all of the secondary air from the air pump is supplied to the reactor, while when the engine is operating at full load all of the secondary air from the air pump is relieved to the ambient atmosphere.

Abstract: A forced air control valve for an air injection system in an internal combustion engine is shifted during cold engine operation to divert air flow to the exhaust manifold upstream of a catalytic converter bed to supply air to the exhaust gases for further combustion prior to entry in the catalytic converter. A diaphragm operated main valve is responsive to a vacuum from the intake manifold for diverting air to the exhaust manifold and a temperature activated vacuum switch shuts off the vacuum when the engine warms up. Upon deceleration during cold engine operation the control valve is shifted to divert air away from the exhaust manifold.

Abstract: A forced air control valve for an air injection system in an internal combustion engine has a diaphragm operated main valve member responsive to the vacuum from intake manifold to divert air from the exhaust system to atmosphere. A separate shifting or diverter valve for the exhaust system is temperature responsive and when the main valve member is open permits the supply of air to the exhaust manifold upstream of a catalytic converter only during cold engine operation. During warm engine operation when the main valve member is open, the separate shifting valve diverts the air to the catalytic converter. Upon deceleration during cold engine operation the separate diverter valve is shifted to divert air from the exhaust manifold to the catalytic converter. A temperature sensitive overheat switch is operable upon overheating of the catalyst to vent the forced air to atmosphere.

Abstract: An air control valve for a vehicle emissions control system has an inlet connected to the output of the vehicle air pump, a first outlet connected to exhaust injection passages in cylinder head, and a second outlet connected downstream into the exhaust manifold. A vacuum actuated valve element is responsive to engine manifold vacuum to divert the output of the air pump from the downstream injection point to the upstream injection point during cold engine operation. However, the air supply from the air pump is diverted from the upstream injection point to the downsteam injection point for a few seconds when a sudden increase in manifold vacuum occurs, such as during engine deceleration when the engine is cold. After the engine warms up, the air supply from the air pump is continuously communicated to the downstream injection point.

Abstract: Disclosed is an apparatus for controlling secondary air for purifying exhaust gas discharged from an internal combustion engine. The apparatus comprises a pair of catalytic converters disposed in series within an exhaust system, a secondary air switching device communicated with two positions each of which is located respectively upstream of each of the catalytic converters, an actuating device for selectively communicating the secondary air switching device with each of the above-mentioned two positions, and a detecting device for detecting the temperature of the first catalytic converter located upstream of the second converter.If the detecting device detects a condition wherein the temperature of the first catalytic converter is lower than a predetermined level, secondary air is supplied to the position upstream of the first catalytic converter.

Abstract: An internal combustion engine employing a siamesed exhaust port arrangement is equipped with a secondary air supply system which is arranged to induct atmospheric air into the exhaust system of the engine in response to the pressure pulsation in the exhaust port. At least two air injection nozzles are disposed open to portions of the exhaust port where they are not affected by the interaction of the pressure pulsations caused by the strokes of two adjacent engine cylinders.

Abstract: An internal combustion engine with an exhaust line in which are arranged a reduction catalyst and downstream thereof an oxidation catalyst, whereby during the starting phase of the internal combustion engine, additional air is supplied to the reduction catalyst, and in the operationally warmed-up condition of the internal combustion engine, additional air is supplied to the oxidation catalyst while at the same time a part of the additional air continues to be fed to the reduction catalyst.

Abstract: A control valve for the exhaust emission control system of the engine for an automotive vehicle controls secondary air flow between a region ahead of a reducing converter and a region intermediate the reducing converter and an oxidizing converter of the system, the amount of air introduced being proportional to engine exhaust flow. The air flow control valve, adapted to be connected to a source of secondary air, includes a first fixed area orifice to control air flow to the region ahead of the reducing converter, a second fixed area orifice and a first diaphragm controlled variable area orifice to control air flow to the region intermediate the reducing converter and the oxidizing converter, a second diaphragm controlled variable area orifice being used to control bypass air flow to the atmosphere.