Abstract: An in-vehicle temperature detection circuit includes a temperature detecting unit including a plurality of individual detecting units, each having a first resistor and a temperature detecting element connected in series between a first conductive path to which a predetermined source voltage is applied and a reference conductive path. A plurality of bipolar transistors are connected to a corresponding individual detecting units. A second conductive path is electrically connected to each of emitters of the bipolar transistors. In each bipolar transistor, a base is electrically connected to a third conductive path between the first resistor and the temperature detecting element of the individual detecting unit corresponding to the bipolar transistor. A voltage reflecting the lowest voltage among the voltages applied to the third conductive paths in the plurality of individual detecting units is applied to the second conductive path.

Abstract: In an internal combustion engine for a vehicle having a drive clutch, a blowby control system includes a fresh air introducing channel, for introducing fresh air into a crankcase, and a blowby gas return channel for returning blowby gas from the crankcase to an air-intake system. A blowby control valve is provided in the fresh air introducing channel or the blowby gas return channel, for selectively restricting gas flow through the blowby system. A controller is also provided on the vehicle for controlling operation of the blowby control valve. The controller is programmed to switch the blowby control valve from the closed state to the open state, with the drive clutch connected, when the vehicle starts traveling. The blowby control system and method hereof can reduce variations in the engine speed occurring during engine idling and before clutch engagement, to improve ride quality of the vehicle.

Abstract: A blowby gas ventilation system for an internal combustion engine capable of preventing oil from being diluted by efficiently and quickly exhausting a blowby gas together with a water content and the like from a crank chamber through forced ventilation of the crank chamber. The blowby gas ventilation system is intended for a four-stroke-cycle internal combustion engine. The system includes a fresh air introduction pipe, through which fresh air is sent from an outside of the internal combustion engine through a throttle portion to a crank chamber. The system also includes a blowby gas return passageway, through which the blowby gas is returned back to a downstream side of an air cleaner.

Abstract: In an internal combustion engine for a vehicle having a drive clutch, a blowby control system includes a fresh air introducing channel, for introducing fresh air into a crankcase, and a blowby gas return channel for returning blowby gas from the crankcase to an air-intake system. A blowby control valve is provided in the fresh air introducing channel or the blowby gas return channel, for selectively restricting gas flow through the blowby system. A controller is also provided on the vehicle for controlling operation of the blowby control valve. The controller is programmed to switch the blowby control valve from the closed state to the open state, with the drive clutch connected, when the vehicle starts traveling. The blowby control system and method hereof can reduce variations in the engine speed occurring during engine idling and before clutch engagement, to improve ride quality of the vehicle.

Abstract: A blowby gas ventilation system for an internal combustion engine capable of preventing oil from being diluted by efficiently and quickly exhausting a blowby gas together with a water content and the like from a crank chamber through forced ventilation of the crank chamber. The blowby gas ventilation system is intended for a four-stroke-cycle internal combustion engine. The system includes a fresh air introduction pipe, through which fresh air is sent from an outside of the internal combustion engine through a throttle portion to a crank chamber. The system also includes a blowby gas return passageway, through which the blowby gas is returned back to a downstream side of an air cleaner.