Abstract: A composite seal ring has a resin seal ring and a metal spring. The resin seal ring is attached in an outer peripheral groove of a valve that opens and closes a passage by a rotational displacement, and the resin seal ring seals between an inner wall of a passage portion that forms the passage and the valve, in the fully closed state of the valve. A metal spring is circularly disposed within a radial width of the resin seal ring. The spring is configured to press the resin seal ring radially outwardly and radially inwardly due to the pressure acting on the resin seal ring or a deformation of the resin seal ring.

Abstract: A composite seal ring has a resin seal ring and a metal spring. The resin seal ring is attached in an outer peripheral groove of a valve that opens and closes a passage by a rotational displacement, and the resin seal ring seals between an inner wall of a passage portion that forms the passage and the valve, in the fully closed state of the valve. A metal spring is circularly disposed within a radial width of the resin seal ring. The spring is configured to press the resin seal ring radially outwardly and radially inwardly due to the pressure acting on the resin seal ring or a deformation of the resin seal ring.

Abstract: A noise silencer for reducing noise in an intake passage in an intake system has a parabolic portion for collecting noise, a noise accumulation room communicating with the intake passage through a communication passage and a noise discharge pipe communicating with an outside space. A noise collection valve is provided in the communication passage. When sound pressure in the intake passage is positive, i.e., larger than pressure inside the noise accumulation room, the noise collection valve opens the communication passage. As a result, a positive sound pressure portion of low-frequency noise is collected into the noise accumulation room and is discharged outside the intake system. Thus, the noise silencer effectively reduces low-frequency noise in the intake passage and requires less mounting space.

Abstract: Fuel supply devices for an engine are disposed within an intake duct located upstream of an air cleaner. Thus, the fuel supply devices such as fuel injection valves and a fuel supply pipe are always cooled by intake air flow while the engine is being driven. In addition, heat conducted from the engine to the fuel supply device can be insulated by the intake duct when the engine is stopped. Further, since the intake duct located upstream of the air cleaner does not dispose functional parts such as a filter therein, a high degree of freedom for mounting the intake duct on the engine is maintained so that the intake duct can be easily disposed at the position where the fuel supply devices are located.

Abstract: An air cleaner, a throttle, a surge tank and air-intake pipes of an intake manifold are combined in a unit and a fuel delivery pipe and fuel injectors are installed in the unit before the unit of an air-intake device is assembled to an internal combustion engine. Cases of the above members are integrally formed thereby to reduce the size of the device and material used for the device. A dusty-side of the air cleaner is disposed under a filter element to prevent dust and water from getting into the clean-side of the filter element when the element is removed to have serviced or inspected.

Abstract: An air cleaner, a throttle, a surge tank and air-intake pipes of an intake manifold are combined in a unit and a fuel delivery pipe and fuel injectors are installed in the unit before the unit of an air-intake device is assembled to an internal combustion engine. Cases of the above members are integrally formed thereby to reduce the size of the device and material used for the device. A dusty-side of the air cleaner is disposed under a filter element to prevent dust and water from getting into the clean-side of the filter element when the element is removed to have serviced or inspected.

Abstract: An air cleaner, a throttle, a surge tank and air-intake pipes of an intake manifold are combined in a unit and a fuel delivery pipe and fuel injectors are installed in the unit before the unit of an air-intake device is assembled to an internal combustion engine. Cases of the above members are integrally formed thereby to reduce the size of the device and material used for the device. A dusty-side of the air cleaner is disposed under a filter element to prevent dust and water from getting into the clean-side of the filter element when the element is removed to have serviced or inspected.