Abstract: An exhaust emission control system for an internal combustion engine has an exhaust passage switching device for switching an exhaust gas flow path, an HC adsorbent material disposed within the main exhaust passage for adsorbing and releasing unburned constituents in exhaust gases, and a control device for controlling the switching device such that the exhaust gas flow path is switched to the main exhaust passage when the unburned constituents is adsorbed by the HC adsorbent material, that the exhaust gas flow path is switched to the bypass exhaust passage when the unburned constituents adsorbed by the HC adsorbent material is released from the HC adsorbent material, and that the exhaust gas flow path is switched to the main exhaust passage when the release of the unburned constituents from the HC adsorbent material is completed.

Abstract: An exhaust gas purifying apparatus for an internal combustion engine is provided for simultaneously realizing sufficient recovery of the adsorbing capability of an adsorbent and limitation to an increase in exhaust resistance. The exhaust gas purifying apparatus for an internal combustion engine comprises a flow path switching valve for switching an exhaust gas flow path to a bypass exhaust passage or to a main exhaust passage, three-way catalysts, and an HC adsorbent arranged in the bypass exhaust passage for adsorbing hydrocarbons in exhaust gases and fully desorbing the adsorbed hydrocarbons when it is heated to a full desorption temperature or higher. A troidal passage of the main exhaust passage completely surrounds a portion of the bypass exhaust passage in which the HC adsorbent is arranged. A ratio S1/S2 of the cross-sectional area S2 of the troidal passage to the cross-sectional area of a flow-in passage is set in a range from 1.

Abstract: For a process for the catalytic conversion of fuel for removing oxides of nitrogen from exhaust gases of internal combustion engines, in which fuel and a part-stream of the exhaust gas or of the intake air are converted in a converter, the fuel and the part-stream of the exhaust gas or of the intake air are fed separately from one another into the converter and the fuel is vaporized in the converter.

Abstract: A device for purifying exhaust gas of diesel engines, in which an oxidizing catalyst, a diesel particulate filter, and an Nox occluding/reducing catalyst are successively disposed in an exhaust gas passage of the diesel engine from the upstream side of the passage, the device for purifying exhaust gas of diesel engines comprising a bypass that connects the upstream side of the oxidizing catalyst with the downstream side thereof in the exhaust gas passage, an exhaust gas passage change-over means for changing-over the exhaust gas flow into either the oxidizing catalyst or the bypass, an air-fuel ratio control means for controlling the air-fuel ratio of the exhaust gas, an NOx occlusion amount detector means for detecting the amount of NOx occluded by the NOx occluding substance, and a controller.

Abstract: An emission control apparatus for an internal combustion engine has a bypass passage bypassing a portion of a main exhaust passage located upstream of an exhaust gas-purifying catalyst device, an adsorbent provided in the bypass passage, a passage switching device for switching between flow of exhaust gas to the bypass passage and flow of exhaust gas to the main exhaust passage, and a bypass flow control device for adjusting a flow that occurs through the bypass passage when the unburned gas component is desorbed (released) from the adsorbent so that the flow through the bypass passage becomes equal to or less than a predetermined flow and assumes a proportion that is equal to or less than a predetermined proportion relative to the flow through the main exhaust passage.

Abstract: An exhaust device for internal combustion engines, having a main catalyst, an auxiliary catalyst, and an exhaust manifold connecting the input of the main catalyst to the exhaust outlets of the internal combustion engine, so as to feed the exhaust gases from the exhaust outlets to the main catalyst; the exhaust manifold assuming a first operating configuration connecting the input of the main catalyst to the output of the auxiliary catalyst, and the input of the auxiliary catalyst to the internal combustion engine, and a second operating configuration connecting the input of the main catalyst directly to the internal combustion engine and excluding the auxiliary catalyst.

Abstract: There are provided a failure determination device simple in construction and capable of properly determining failure of a humidity sensor that detects the humidity of exhaust gases from an internal combustion engine and a control system for an exhaust passage changeover valve, which can switch the changeover valve with appropriate timing, thereby enabling sufficient purification of exhaust gases. In one form of the invention, an operating condition of the engine is detected. It is judged based on the detected operating condition of the engine whether or not the engine is in an operating condition in which failure determination of the humidity sensor can be executed. It is determined whether or not the humidity sensor has failed, based on a result of detection by the humidity sensor, when it has been judged that the failure determination of the humidity sensor can be executed.

Abstract: An exhaust purifying apparatus for an internal combustion engine includes a catalyst that purifies exhaust gas from the engine, a first passage that allows exhaust gas to flow from the engine to the catalyst, and a second passage that allows exhaust gas to flow from the engine to the catalyst. The first passage includes an accelerated cooling portion whose cross section is designed so that a relatively large quantity of heat is released from the exhaust gas in the first passage, and the second passage has a cross section designed so that a relatively small quantity of heat is released from the exhaust gas in the second passage.

Abstract: It is an object of the present invention to effectively utilize the performance of an adsorbent by providing an art for controlling flow of exhaust gas to the adsorbent in accordance with a mode in which unburnt fuel components discharged from an internal combustion engine reach the adsorbent or a mode in which the unburnt fuel components adsorbed by the adsorbent are desorbed therefrom.

Abstract: A nitrogen oxide absorbing material (38) which absorbs nitrogen oxide when the reduction component concentration of exhaust gas in the exhaust passage (31) of an engine (1) is lower than a predetermined concentration, and discharges nitrogen oxide when the reduction component concentration of exhaust gas in the exhaust passage (31) of the engine (1) is higher than the predetermined concentration, and a catalyst (38) which promotes reduction of the discharged nitrogen oxides by a reduction component are provided. A controller (40) first reduces the reduction component concentration of the exhaust gas over a first predetermined time period by, for example, advancing the fuel injection timing. The controller (40) then increases the reduction component concentration of the exhaust gas over a second predetermined time period by, for example, retarding the fuel injection timing.

Abstract: An apparatus and a method for enhancing the rate of a chemical reaction in a gas stream. The apparatus includes at least one heterogeneous catalyst having an upstream end and a downstream end, and at least one surface having a plurality of catalytically active sites on the surface, where the catalyst is positioned so that at least a portion of the gas stream contacts at least a portion of the catalytically active sites on the surface. At least one device for producing radicals or other active species from at least one of water vapor or other gaseous species, such as a corona discharge device or a UV light source is used to produce radicals or other active species, which are introduced into the gas stream at a position upstream of the downstream end of the catalyst.

Abstract: A diagnostic equipment for an exhaust gas cleaning apparatus installed for an engine, comprising a misfire detector which detects the misfire of the engine, and a secondary-air-system failure detector which detects the failure of a secondary air system. An index corrector corrects a deterioration index calculated by a deterioration-index calculator, in accordance with the detected result of the detector. A deterioration decision unit decides if the diagnostic equipment has failed, by the use of the corrected deterioration index. In a case where the extent of the misfire or the like is severe, a decision interrupter interrupts the decision of the deterioration decision unit. Thus, even when the misfire of the engine or the failure of the secondary air system has occurred, the detection of the deterioration of a catalyst does not err. It is therefore avoided to erroneously replace the catalyst which has not deteriorated yet, or to run the engine in spite of the deterioration of the catalyst.

Abstract: A fault determining apparatus for an exhaust passage switching valve which is capable of directly, rapidly and properly determining a fault in an exhaust passage switching valve, under conditions such as immediately after the start of an internal combustion engine, in which the switching valve should be essentially operated, without the need for setting a special fault determining mode. The fault determining apparatus determines a fault in the exhaust passage switching valve for switching an exhaust passage of exhaust gases discharged from an internal combustion engine between a main exhaust passage having a three-way catalyst and a bypass exhaust passage having filled in an intermediate portion thereof an adsorbent capable of adsorbing hydrocarbons and moisture in the exhaust gases in accordance with an activated state of the three-way catalyst.

Abstract: A method and apparatus for purifying an exhaust gas of an internal combustion engine includes an ammonia generating catalyst for generating ammonia from nitrogen oxides contained in the exhaust gas to be purified, and a nitrogen oxide reducing catalyst downstream of the ammonia generating catalyst, for reduction of nitrogen oxides contained in the exhaust gas to be purified. Generated ammonia is used as the reducing agent. A nitrogen oxide adsorption catalyst is arranged upstream of the ammonia generating catalyst, or the ammonia generating catalyst is arranged in an exhaust pipe branch which pertains to only a part of several separately controllable internal-combustion sources. One or more additional exhaust pipe branches assigned to the other internal-combustion sources and lead to the nitrogen oxide reducing catalyst, while bypassing the ammonia generating catalyst.

Abstract: An engine comprising a silencer in the exhaust passage thereof, wherein an exhaust gas flow passage pipe is arranged in the silencer body and a particulate filter is arranged inside the exhaust gas flow passage pipe. A first exhaust gas inflow-outflow opening and a second exhaust gas inflow-outflow opening of the exhaust gas passage pipe and an exhaust gas inflow opening to the silencer body are arranged at one end of the silencer body. The exhaust gas is selectively supplied to the first exhaust gas inflow-outflow opening, second exhaust gas inflow-outflow opening, and exhaust gas inflowing opening.

Abstract: An exhaust gas purifying apparatus for an internal combustion engine is provided for simultaneously realizing sufficient recovery of the adsorbing capability of an adsorbent and limitation to an increase in exhaust resistance. The exhaust gas purifying apparatus for an internal combustion engine comprises a flow path switching valve for switching an exhaust gas flow path to a bypass exhaust passage or to a main exhaust passage, three-way catalysts, and an HC adsorbent arranged in the bypass exhaust passage for adsorbing hydrocarbons in exhaust gases and fully desorbing the adsorbed hydrocarbons when it is heated to a full desorption temperature or higher. A troidal passage of the main exhaust passage completely surrounds a portion of the bypass exhaust passage in which the HC adsorbent is arranged. A ratio S1/S2 of the cross-sectional area S2 of the troidal passage to the cross-sectional area of a flow-in passage is set in a range from 1.

Abstract: The invention is directed to an apparatus and a method for the reduction of pollutants in the exhaust stream of a combustion engine. Radicals are produced using a corona discharge in the combustion gas stream of the engine, either in the precombustion gas stream or from water in the exhaust gas. When the radicals are produced from the exhaust gas stream, the radicals may be produced using a corona discharge placed directly in the exhaust stream leading to the catalytic convertor, or a portion of the exhaust stream may be diverted to a remote corona discharge radical generator. The corona discharge in the generator produces radicals in the diverted exhaust gas, and the exhaust gas containing radicals is then conveyed to the exhaust gas stream at a point upstream of the catalytic convertor.

Abstract: The invention is directed to an apparatus and a method for the reduction of pollutants in a gas stream containing gas formed from the oxidation of fuel, such as, in the exhaust stream of a combustion engine. Radicals are produced using a corona discharge in the combustion gas stream of the engine, either in the precombustion gas stream or from water in the exhaust gas. When the radicals are produced from the exhaust gas stream, the radicals may be produced using a corona discharge placed directly in the exhaust stream leading to or within the catalytic converter, or a portion of the exhaust stream may be diverted to a remote corona discharge radical generator. The corona discharge in the generator produces radicals in the diverted exhaust gas, and the exhaust gas containing radicals is then conveyed to the exhaust gas stream at a point upstream of the outlet of the catalytic converter.

Abstract: In an exhaust control valve having a valve housing and a valve body rotatably contained in the valve housing, a transmission member is fitted to an outer end of the valve shaft and protrudes from the outside of the valve housing. A bearing bushing for rotatably bearing an external circumferential surface of the valve shaft by its internal circumferential surface and rotatably bearing an end face of the valve body by its end face is mounted in the valve housing. The valve body is urged by load from a thrust spring for achieving a pressure contact seal condition between the opposed end faces of the bearing bush and the valve body.

Abstract: An internal combustion engine having a lean NOx catalyst is capable of relieving a load upon an engine fuel injection device by eliminating the use of sub-injection, and of well purifying an exhaust gas and recovering from S-poisoning even by eliminating the use of the sub-injection. The internal combustion engine has a combustion heater for allowing a flow of combustion gas through an engine intake passageway to raise temperatures of engine related elements, a lean NOx catalyst, provided in an engine exhaust passageway, for purifying an engine exhaust gas, and a combustion gas introducing passageway for introducing at least some proportion of a combustion gas emitted by the combustion heater, toward upstream of the lean NOx catalyst in the engine exhaust passageway from the engine intake passageway when making a request for a reproducing process of the lean NOx catalyst.

Abstract: An exhaust purifying method and apparatus of an internal combustion engine is provided with an exhaust switch valve for switching a flow of exhaust gas flowing into an exhaust filter. By switching the exhaust switch valve, the exhaust gas is fed from one side and the other side of the filter, thereby stirring the soot (particulates) in the exhaust gas deposited on the filter having a NOx absorbent and an active-oxygen discharging agent supported thereon. Thus, the soot in the exhaust gas is continuously burned. Moreover, the switching of the exhaust switch valve and the rich spike are inhibited from being conducted simultaneously. In the case where the rich spike is conducted in order to discharge and reduce NOx absorbed in the NOx absorbent, the exhaust gas containing a large amount of HC and CO can be prevented from being discharged into the atmosphere without being purified.

Abstract: An improved exhaust gas control device that has a hollow diverter pipe to divert exhaust around the muffler and in which a gate valve is slidably mounted to open and close the hollow pipe thus either forcing the exhaust gas through the muffler or diverting it to the atmosphere.

Abstract: A system for purifying exhaust gas generated by an internal combustion engine having a bypass exhaust gas passage branching from an exhaust pipe which is opened or closed by a switch-over valve, and an adsorbent which adsorbs unburneds component in the exhaust gas installed at the bypass exhaust passage. In the system, when the engine operation is within a high engine speed and high load region, the switch-over valve is operated to open the bypass exhaust gas passage to reduce noise due to switch-over valve chattering, etc. Similarly, the bypass exhaust gas passage is opened at that range, when the exhaust gas temperature is greater or equal to a predetermined value, to introduce high temperature exhaust gas to burn away cloggy material adhered to the adsorbent which would otherwise deteriorate or degrade the adsorbent.

Abstract: An exhaust purifying apparatus for an internal combustion engine includes a catalyst that purifies exhaust gas from the engine, a first passage that allows exhaust gas to flow from the engine to the catalyst, and a second passage that allows exhaust gas to flow from the engine to the catalyst. The first passage includes an accelerated cooling portion whose cross section is designed so that a relatively large quantity of heat is released from the exhaust gas in the first passage, and the second passage has a cross section designed so that a relatively small quantity of heat is released from the exhaust gas in the second passage.

Abstract: An exhaust gas treatment device has a cylindrical body with axial passages having a catalyst and a central cavity. A filter is provided in the cavity and the cylindrical body is mounted for rotation in a housing through which the exhaust gas flows.

Abstract: According to the present invention, there is provided an exhaust gas purification device, comprising a NOx absorbent arranged in an exhaust passage of an engine for absorbing NOx therein when an air-fuel ratio of an exhaust gas flowing into the NOx absorbent is lean, the NOx absorbent discharging NOx absorbed therein when a concentration of the oxygen in the exhaust gas flowing into the NOx absorbent decreases, a trapping element arranged in the exhaust passage upstream of the NOx absorbent for trapping particulates, a processing element for processing the particulates trapped in the trapping element to regenerate the trapping element, and a preventing element for preventing the exhaust gas from flowing into the NOx absorbent from the trapping element when the trapping element is regenerated.

Abstract: In the case of an internal combustion engine (1) arranged transversely in a motor vehicle and having in-line cylinders, the exhaust gases are passed forwards in the direction of travel around the internal combustion engine from that side of the latter which is opposite to the direction of travel and, from there, pass to a catalytic converter (8) arranged in the rear area of the motor vehicle. To ensure rapid heating of the catalytic converter when cold-starting, the exhaust manifold (2) of the internal combustion engine is connected to the inlet of the catalytic converter (8) by a short feed line (5) with a small cross section. An exhaust-gas recirculation line (15) which opens into line (4) close to the catalytic converter is provided.

Abstract: An exhaust emission control system of an internal combustion engine desorbs SOx by reversing a flow of an exhaust gas through an NOx storage-reduction catalyst, of which a structure is simplified as follows. A first exhaust pipe connected to an engine is connected to a first port of an emission switching valve having four ports. A second exhaust pipe 10, through which the exhaust gas is discharged into the atmospheric air, is connected to a second port, a third exhaust pipe connected to an inlet of a catalytic converter is connected to a third port. A fourth exhaust pipe connected to an outlet of the catalytic converter 30 is connected to a fourth port. When the emission switching valve is set in a forward flow position, the first exhaust pipe is connected to the third exhaust pipe, and the second exhaust pipe is connected to the fourth exhaust pipe, whereby the exhaust gas flows toward the outlet from the inlet within the catalytic converter.

Abstract: In an exhaust gas purification device, a catalytic converter containing selective reduction catalysts is disposed in an exhaust gas passage of an internal combustion engine capable of being operated at a lean air-fuel ratio. The catalytic converter includes a plurality of the selective reduction catalysts disposed in series in the casing of the catalytic converter. Bypass passages which supply the exhaust gas to downstream selective reduction catalysts in the casing by bypassing the upstream catalysts are provided. When a reducing agent is supplied to the exhaust gas upstream of the converter, a part of the supplied reducing agent directly reaches the downstream selective reduction catalyst through the bypass passages without being oxidized by the upstream selective reduction catalysts. Therefore, the NOx purifying abilities of the downstream catalysts are improved and the formation of sulfates on the downstream catalysts is suppressed.

Abstract: A method for controlling the temperature of an exhaust gas treatment system in the exhaust system of an internal combustion engine in the region of a predetermined intended temperature, comprising a two-position device for varying the temperature of the exhaust gases, a device for measuring the actual temperature and a device for determining a quantity which approximately represents a value for the input of energy into the exhaust gas treatment system is described, as is an apparatus for putting the method into practice. The actual temperature is compared with the intended temperature in a two-step control element and an output signal is produced.

Abstract: A catalytic converter includes a casing connected to the output from an exhaust gas and residue manifold of an engine, in particular an engine of a motor vehicle. The casing contains arrangements for oxidizing the exhaust gases and residues and for trapping the oxidized gases and residues. A central part of the casing houses cooling arrangements for reducing the temperature of the gases and residues upstream of the trapping arrangements below a predetermined threshold.

Abstract: A catalyst is housed in a casing arranged in the exhaust passage of the engine. A pressure reducing valve, which is usually closed, is arranged in a bypass passage branching off from the exhaust passage upstream of the casing. The fuel injector usually injects fuel at the combustion stroke or the exhaust stroke to feed hydrocarbon, and NOX is reduced in the catalyst by the hydrocarbon. When the catalyst is judged to be poisoned, the timing of the secondary fuel injection is advanced with respect to the timing of the usual secondary fuel injection, and the pressure reducing valve is opened to reduce the pressure in the casing. In this way, the catalyst is reactivated.

Abstract: An emission control system for an internal-combustion engine has at least one nitrogen oxide adsorber for the periodic adsorption and desorption of nitrogen oxides contained in the exhaust gas of the internal-combustion engine. A desorption gas pipe has an externally heatable catalyst arranged therein to which a mixture of air and/or exhaust gas can be fed as well as fuel at an at least stoichiometric proportion. This mixture is burned to form a desorbing gas flow which is fed to the respective nitrogen oxide adsorber for the nitrogen oxide desorption.

Abstract: The invention relates to an exhaust element (10) of a motor vehicle with an internal-combustion engine. It includes a main exhaust pipe (16) and a bypass (18) mounted in parallel with the main exhaust pipe (16). The bypass (18) includes a heat exchanger (20). Moveable means (28) for shutting off the main pipe (16) and moveable means (30) for regulating the cross section offered for the gases to pass in the bypass (18) are arranged in the exhaust element. It further includes mechanical means (32) for synchronizing the means (28) for shutting off the main pipe (16) and means (30) for regulating the cross section for the gases to pass in the bypass (18), under the control of a single actuating element.

Abstract: An exhaust stream aftertreatment system that selectively reduces NOx emissions during lean-burn operation of an internal combustion engine is provided. The apparatus includes a partial oxidation reactor having a fuel source, an ignition device, and various values. The partial oxidation reactor is disposed in the exhaust pipe of automobile between the engine and the threeway catalyst. A light-off catalyst is provided adjacent to the engine, upstream from the partial oxidation reactor. The three-way catalyst and the light-off catalyst are typical automotive catalysts having a substrate plated with a precious metal to facilitate the oxidation of hydrocarbons (HC) and carbon monoxide (CO) as well as the reduction of nitrogen monoxide and nitrogen dioxide (NOx). The partial oxidation reactor is adapted to operate while the internal combustion engine is producing high levels of NOx or while the engine is operating in a lean burn regime.

Abstract: A new method, system, and apparatus are described for the adsorption and concentration of adsorbable pollutants. The invention allows for simultaneous pollutant adsorption and pollutant concentration. The invention is particularly useful in treating the exhaust of internal combustion engines containing adsorbable pollutants which can be concentrated and then treated to form harmless effluents.

Abstract: An apparatus and a method for enhancing the rate of a chemical reaction in a gas stream. The apparatus includes at least one heterogeneous catalyst having an upstream end and a downstream end, and at least one surface having a plurality of catalytically active sites on the surface, where the catalyst is positioned so that at least a portion of the gas stream contacts at least a portion of the catalytically active sites on the surface. At least one device for producing radicals or other active species from at least one of water vapor or other gaseous species, such as a corona discharge device or a UV light source is used to produce radicals or other active species, which are introduced into the gas stream at a position upstream of the downstream end of the catalyst.

Abstract: A catalytic converter for an internal combustion engine having a housing provided with an exhaust gas by-pass tube and a valve arrangement that causes the exhaust gas to selectively flow through a catalyst coated substrate to be treated thereby or through the tube so as to exist the converter in an untreated state and in which an actuator is in a sealed relationship with the housing so as to prevent exhaust gas leakage while providing for movement of the valve.

Abstract: Exhaust gas is caused to flow through a bypass passage during an adsorption mode. At this time, an adsorbing member adsorbs harmful components, e.g. HC, of the exhaust gas. Also, exhaust gas is caused to flow through the bypass passage to thermally desorb the harmful component held at the adsorbing member during a desorption mode. A quantity of heat given from exhaust gas to the adsorbing member during the desorption mode is calculated based on an operation state of an engine. It is determined that the desorption of the harmful components has been finished when the quantity of heat given to the adsorbing member reaches a total quantity of heat required for totally desorbing the harmful components adsorbed by the adsorbing member.

Abstract: In a transverse-mounted cylinder-in-line internal combustion engine (1) fitted in a motor vehicle, the exhaust gases from the side of the internal combustion engine opposite to the direction of travel are led forwardly round the internal combustion engine and from there reach an NOx trap (8) arranged in the middle region of the vehicle. For rapid heating up on cold starting the three-way converter (12) is arranged immediately after the exhaust manifold (2), and in addition when a valve (9) is closed the exhaust gases are led through a short supply duct (5) directly to an exhaust duct (13) which opens into an NOx trap.

Abstract: A diagnostic apparatus for exhaust gas clarification apparatus for internal combustion engine diagnoses the individual catalyst independently by an air/fuel ratio sensor mounted before and after the individual catalyst. The individual catalyst is diagnosed by estimating the correlation of the output signals from the air/fuel ratio sensors mounted before and after the individual catalyst. The individual diagnosis operation is performed at distinctive operation regions adequate for their corresponding diagnostic mode. A by-pass route is provided for by-passing the exhaust gas from the upstream catalyst, and a by-pass valve switches the exhaust gas flow into the upstream catalyst or into the by-pass routes. A cross-correlation function calculation valve based upon outputs from air/fuel ratio sensors permits diagnosis of degradation of the overall catalyst.

Abstract: A device for purifying exhaust gas includes an HC adsorbent and an exhaust gas purifying catalyst disposed in an exhaust gas passage in this order from the upstream side. The exhaust gas purifying catalyst is provided with an O.sub.2 storage capability, i.e., the exhaust gas purifying catalyst is capable of absorbing oxygen in the exhaust gas when the air-fuel ratio of the exhaust gas is lean, and is capable of releasing the absorbed oxygen when the air-fuel ratio of the exhaust gas becomes rich. When the engine starts, the HC adsorbent adsorbs HC in the exhaust gas. When the temperature of the exhaust gas becomes high, the HC adsorbent releases the adsorbed HC. The device also includes an engine control unit which operates the engine at a lean air-fuel ratio during a predetermined period before the releasing of the HC from the HC adsorbent occurs. Therefore, oxygen is absorbed and stored in the exhaust gas purifying catalyst before the releasing of HC occurs.

Abstract: The invention relates to a process for controlling a particulate filter in the exhaust of a Diesel engine using an after-treatment of the particulates while requiring a minimum amount of energy. The process according to the invention adapts the geometry of a filter placed in the exhaust gas flow according to predetermined strategies linked with the running of the engine, the process being such that it limits a mean back pressure of the engine which degrades engine efficiency.

Abstract: A system for purifying exhaust gas generated by an internal combustion engine including a bypass branching out from the exhaust pipe downstream of a catalyst and merging to the exhaust pipe, an adsorber installed in the bypass, a bypass valve member which closes the bypass, and an EGR conduit connected to the bypass at one end and connected to the air intake system for recirculating the exhaust gas to the air intake system. The bypass valve member is opened for a period after engine startup to introduce the exhaust gas such that the adsorber installed in the bypass adsorbs the unburnt HC component in the exhaust gas. The adsorber adsorbs the HC component when the exhaust temperature rises and the adsorbed component is recirculated to the air intake system through the EGR conduit. In the system, the bypass valve is provided at or close to the branching point in the exhaust pipe and a chamber is provided close to the branching point such that the conduit is connected to the bypass at the one end in the chamber.

Abstract: The invention is directed at an engine exhaust system comprising: (1) a main catalyst located downstream from engine; (2) a honeycomb adsorber structure having an inlet and outlet end disposed in a housing and located downstream from the main catalyst, the honeycomb structure having a first substantially unobstructed flow region (a by-pass port) having an inlet face, and a second more obstructed flow region adjacent the first region (plurality of channels) having a second inlet face, the inlet face of the first region located upstream that of the inlet face of the second region; (3) a fluidics apparatus disposed in the housing and comprising a diverter body located upstream and proximate to the inlet face of the first region, a diversion fluid source conduit for directing the diversion fluid, proximate the diverter body; and, (4) a burn-off catalyst located downstream of the honeycomb adsorber.

Abstract: A device for purifying the exhaust gas of an internal combustion engine is disclosed. The device comprises a collision collecting type filter for collecting particulates which is arranged in an exhaust passage, can vary a pressure in the exhaust passage on at least one of the upstream side and downstream side of said filter, determines that the collected particulates have been burned and the filter has been regenerated, and suddenly changes the pressure in the exhaust passage when it is determined that the filter has been regenerated.

Abstract: A thermal management system for catalytic converters of an automotive internal combustion engine includes exhaust pipes from one bank of cylinders crossing over to a second side of the engine to a catalytic converter, while the exhaust pipe from the other bank of cylinders crosses over to the first side of the engine to connect to a corresponding catalytic converter, thereby resulting in a crosswise pattern of exhaust flow. Bypass pipes connect between the exhaust pipes of one bank of cylinders directly to the catalytic converter located on the same side of the engine to provide a short exhaust path to rapidly heat the converter.

Abstract: A system for purifying an exhaust gas for use in an automobile is disclosed which does not externally discharge unburnt hydrocarbons until a catalyst becomes active. An adsorbent is provided upstream of the catalyst. A heat exchanger is disposed between an upstream portion of the adsorbent and a portion between the adsorbent and the catalyst for controlling the elevation of the temperature of the adsorbent and for promoting the elevation of the temperature of the catalyst. The unburnt hydrocarbons are absorbed by the adsorbent 4 in the initial period of time from starting of an engine until the catalyst 8 becomes active. Temperature control is made in such a manner that the unburnt hydrocarbons which are adsorbed by the adsorbent 4 begins to be desorbed therefrom substantially simultaneously with the time when the catalyst 8 begins to function.

Abstract: A modified in-line adsorber system capable of meeting the California ultra-low emission vehicle (ULEV) standard using a combination of burn-off catalyst and a modified adsorber constructed with an open flow region of substantially unobstructed flow having a hole or a region of larger cell openings to increase the amount and rate of contact between the exhaust gas and the burn-off catalyst, and thereby reduce the light-off time of the burn-off catalyst. For best effect, the open flow region of the adsorber is positioned along the exhaust stream between the engine and the burn-off catalyst as defined by the exhaust flow path of least resistance.

Abstract: In order to reduce the exhaust gas emissions of automotive vehicle combustion engines including exhaust gas catalytic converters, the exhaust gases are caused to flow between the engine and the catalytic converter through conduit branches of different thermal characteristics. Said conduit branches comprise a full load tube and a partial load tube, with the full load tube surrounding the partial load tube so as to provide an annular space between the full load tube and the partial load tube.