Abstract: The purpose of the present invention is to provide a lubricating oil composition capable of achieving good wear resistance and good scoring resistance of a bearing in addition to further fuel saving while maintaining durability and seizure resistance that can be used as a gear oil for a high-output, high-speed gear mechanism. A lubricating oil composition containing a combination of Fischer-Tropsch derived base oil having a low kinematic viscosity at high temperature, polyalphaolefin having a high kinematic viscosity at high temperature, and ester compound of a trivalent or higher polyol having a low kinematic viscosity at high temperature, and further contains a partial ester compound of an unsaturated fatty acid and a polyol, including a monoester compound of the unsaturated fatty acid and the polyol.

Abstract: An improved blow-by gas return structure minimizes the occurrence of a drawback caused by freezing at a low temperature by bringing a state where freezing minimally occurs in a blow-bay gas passage such as a pipe disposed outside an engine. The blow-by gas return structure is configured such that a blow-by gas is introduced into an intake manifold through an inner passage formed in a head cover. The blow-by gas return structure includes an outer pipe which connects a blow-by gas outlet of the head cover and a blow-by gas inlet of a main pipe of the intake manifold in a communicable manner, and a temperature elevating mechanism configured to elevate a temperature of the blow-by gas inlet. The temperature elevating mechanism is configured such that a cooling water transfer passage is formed in a portion of the blow-by gas inlet of the main pipe.

Abstract: An improved blow-by gas return structure minimizes the occurrence of a drawback caused by freezing at a low temperature by bringing a state where freezing minimally occurs in a blow-bay gas passage such as a pipe disposed outside an engine. The blow-by gas return structure is configured such that a blow-by gas is introduced into an intake manifold through an inner passage formed in a head cover. The blow-by gas return structure includes an outer pipe which connects a blow-by gas outlet of the head cover and a blow-by gas inlet of a main pipe of the intake manifold in a communicable manner, and a temperature elevating mechanism configured to elevate a temperature of the blow-by gas inlet. The temperature elevating mechanism is configured such that a cooling water transfer passage is formed in a portion of the blow-by gas inlet of the main pipe.

Abstract: An intake device of a multicylinder engine includes an intake manifold having a collector portion extending in a front-rear direction, an intake air introducing portion disposed at a center in the front-rear direction of the collector portion, and branch portions led out from front and rear end portions and of the collector portion. The branch portions are connected to an intake port of a cylinder head. A throttle body is disposed at an upper portion of the intake air introducing portion, and has a butterfly-type throttle valve, a valve shaft of which is oriented in the front-rear direction. A blow-by gas inlet portion is provided to the intake air introducing portion 4 of the intake manifold, and is disposed on a side to which a lower end portion of the half-open throttle valve is directed and on a downstream side of the lower end portion.

Abstract: An exhaust manifold is covered by a manifold heat shield cover and an exhaust pipe is directed downward from the exhaust manifold. In such an engine, a cooling fan is disposed on a front portion of the engine and the exhaust pipe is positioned on the air flow path of the cooling fan. An auxiliary component heat shielding plate is directed from the manifold heat shield cover along a back side of the exhaust pipe. An auxiliary engine component is disposed beneath the manifold heat shield cover on a back side of the auxiliary component heat shielding plate. Between the exhaust pipe and a cylinder block, an air flow guide plate provides an air flow space between the air flow guide plate and the cylinder block. A cooling air flow passing through the air flow space is thus supplied to the auxiliary engine component.

Abstract: An intake device of a multicylinder engine includes an intake manifold having a collector portion extending in a front-rear direction, an intake air introducing portion disposed at a center in the front-rear direction of the collector portion, and branch portions led out from front and rear end portions and of the collector portion. The branch portions are connected to an intake port of a cylinder head. A throttle body is disposed at an upper portion of the intake air introducing portion, and has a butterfly-type throttle valve, a valve shaft of which is oriented in the front-rear direction. A blow-by gas inlet portion is provided to the intake air introducing portion 4 of the intake manifold, and is disposed on a side to which a lower end portion of the half-open throttle valve is directed and on a downstream side of the lower end portion.

Abstract: An exhaust manifold is covered by a manifold heat shield cover and an exhaust pipe is directed downward from the exhaust manifold. In such an engine, a cooling fan is disposed on a front portion of the engine and the exhaust pipe is positioned on the air flow path of the cooling fan. An auxiliary component heat shielding plate is directed from the manifold heat shield cover along a back side of the exhaust pipe. An auxiliary engine component is disposed beneath the manifold heat shield cover on a back side of the auxiliary component heat shielding plate. Between the exhaust pipe and a cylinder block, an air flow guide plate provides an air flow space between the air flow guide plate and the cylinder block. A cooling air flow passing through the air flow space is thus supplied to the auxiliary engine component.

Abstract: A method of controlling an intake air passage of an internal combustion engine is provided. The intake air passage cyclically communicates to a combustion chamber of the internal combustion engine, thereby inducting fresh air into said combustion chamber. The cyclic communication of the intake air passage to the combustion chamber generates a pressure wave in the intake air passage. The method comprises reducing an effective length of a transmission path of the pressure wave in an upstream direction of the intake air passage as a desired air flow to the combustion chamber decreases. In accordance with the method, the effective length of the pressure wave transmission path is reduced as desired air flow decreases. With the reduced effective length, the pressure wave bounces back and forth between ends of the transmission path more often before the next cyclic communication. The more bouncing attenuates the pressure wave at the next cyclic communication.

Abstract: A method of controlling an intake air passage of an internal combustion engine is provided. The intake air passage cyclically communicates to a combustion chamber of the internal combustion engine, thereby inducting fresh air into said combustion chamber. The cyclic communication of the intake air passage to the combustion chamber generates a pressure wave in the intake air passage. The method comprises reducing an effective length of a transmission path of the pressure wave in an upstream direction of the intake air passage as a desired air flow to the combustion chamber decreases. In accordance with the method, the effective length of the pressure wave transmission path is reduced as desired air flow decreases. With the reduced effective length, the pressure wave bounces back and forth between ends of the transmission path more often before the next cyclic communication. The more bouncing attenuates the pressure wave at the next cyclic communication.

Abstract: The present invention provides a serum uric acid decreasing agent which contains interleukin-6 (IL-6) as the active ingredient together with a pharmaceutically acceptable carrier; and a method for decreasing the serum uric acid level which comprises administering interleukin-6 (IL-6) in an effective amount to a patient.