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 an engine, if a catalytic converter is not in the activated region, a fuel injection rate is corrected to increase, and a secondary air is introduced from a secondary air feed port into a catalytic converter. Even immediately after the cold start of the engine, the fuel injection rate is increased to be richer in fuel than the stoichiometric air/fuel ratio to feed the secondary air simultaneously, so that the temperatures of the catalytic converter and the exhaust gas can be kept over the activation temperature by the heat of the reaction of the increased fuel in the catalytic converter thereby to improve the exhaust gas purification.

Abstract: An exhaust gas purifying apparatus with a failure diagnosis function is provided. A failure diagnosis device determines that the apparats is failed when the temperature rising speed of an adsorbing device is equal to a set value or less during a gas adsorption process and if the temperature rising speed is equal to an upper limit or more or to a lower limit or less during a gas desorption process. Further, a failure diagnosis device similarly monitors the flow passing through the adsorbing device. A failure diagnosis device determines that the apparatus is failed if the concentration of discharge gas is equal to a set value or more in a discharge passage. And further, a failure diagnosis device measures the concentration of discharge gas flowing through a return passage to accumulate the amount of discharge gas in order to determine that the apparatus is failed if the accumulated value is equal to a set value or less.

Abstract: A change-over valve unit has a change-over valve for switching a bypass passage and an exhausting passage disposed in parallel therewith. An adsorbent is disposed in the bypass passage to adsorb exhaust components. An actuator of the change-over valve is isolated from an adsorption cylinder by a pedestal. Furthermore, rotary shafts of the control mechanism of the change-over valve are positioned within the bypass passage of the adsorber when the change-over valve is positioned to open the main exhaust passage. Thus, the heat of the exhaust gas flowing through the main exhaust passage is not transmitted to the rotary shafts.

Abstract: It is the primary object of the present invention to provide a catalyst converter which can hold a sufficient amount of catalyst to raise the temperature thereof to the catalyst activation temperature in a short time without enlarging the metal carrier itself. The metal carrier 1 is arranged in the course of an exhaust manifold 3 of an engine 2 and is composed of an alternating winding of a flat sheet 7 and a corrugated sheet 8, wherein slit parts 9 are formed in the flat sheet 7 and the corrugated sheet 8 of the metal carrier 1 in an end portion thereof, on the side the engine 2.

Abstract: In an automotive engine exhaust pipe having a main flow passage and a bypass flow passage, the exhaust gas flows through the bypass flow passage having an heater-provided catalyst when an engine starts. After a main catalyst reaches a catalytic activation temperature, a switching valve switches the exhaust gas to flow through the main flow passage. The main shaft is divided into a driven shaft inserted into a bearing hole and a driving shaft inserted into another bearing hole, and therefore, a total length thereof in an axial direction is shorter than a length of the main shaft without having segments. Therefore, even though the driven shaft and the driving shaft are deformed into the arch shape, a deformation amount thereof is reduced so that inner peripheries of the bearing holes are not rubbed against the shafts.

Abstract: A variable damping force shock absorber control system for an automotive vehicle is provided. This control system includes a variable damping force shock absorber adapted to have a plurality of damping modes of operation each assuming different damping characteristics, a vertical acceleration sensor for detecting vertical acceleration acting on a vehicle body, and a control unit. The control unit mathematically determines vertical speed of the vehicle body based on the vertical acceleration to select one of the damping modes based on the vertical speed, and determines the amount of damping force in each damping mode according to a vibratory condition indicative parameter which is varied as a function of a variation in amplitude of the vertical acceleration.