Abstract: An engine includes an electric supercharger as a first supercharger, a turbocharger as a second supercharger, a secondary air supply passage, a secondary air valve and a catalyst. The electric supercharger is provided in an intake passage which is in communication with a combustion chamber, and supercharges intake air into the combustion chamber. The turbocharger is provided in the intake passage in series with respect to the electric supercharger, and supercharges intake air to the combustion chamber. The secondary air supply passage and the secondary air valve supply air compressed by the electric supercharger to a discharge passage which is in communication with the combustion chamber. The catalyst is provided in the discharge passage to purify exhaust gas.

Abstract: An engine includes an electric supercharger as a first supercharger, a turbocharger as a second supercharger, a secondary air supply passage, a secondary air valve and a catalyst. The electric supercharger is provided in an intake passage which is in communication with a combustion chamber, and supercharges intake air into the combustion chamber. The turbocharger is provided in the intake passage in series with respect to the electric supercharger, and supercharges intake air to the combustion chamber. The secondary air supply passage and the secondary air valve supply air compressed by the electric supercharger to a discharge passage which is in communication with the combustion chamber. The catalyst is provided in the discharge passage to purify exhaust gas.

Abstract: A belt drive device is constructed by looping a timing belt 14 about a driving sprocket 9, a cam sprocket 11, and a driven sprocket 12 for transmitting a driving force from the driving sprocket 9 to the sprockets 11, 12. A dynamic damper 15, comprising a ring mass 153 and an elastic ring 152 for holding the ring mass 153, is mounted on the driven sprocket 12 that has the largest amplitde of torque fluctuation among the sprockets 11, 12. The dynamic damper 15 absorbs revolution fluctuations of the driven sprocket 12 that has the largest amplitude of torque fluctuation. Thus, at the time of resonance during which the belt load on the timing belt 15 sharply increases, the sharp increase in the timing belt load can be minimized, and maximum load on the timing belt 15 can be decreased, whereby the durability of the timing belt 15 can be secured.

Abstract: An ignition timing controller is furnished for use in a spark-ignition internal combustion engine. The controller includes a device for setting the ignition timing of the engine in accordance with the state of operation of the engine and another device for actuating an ignition system on the basis of the ignition timing set by the ignition timing setting device. The ignition timing setting device is constructed of a device for estimating the wall temperature of a combustion chamber of the engine from a variable, which indicates the quantity of combustion energy of the engine, and another device for calculating the ignition timing from the wall temperature of the combustion chamber estimated by the wall temperature estimating device.