Abstract: A clutch control device is provided for a four-wheel drive vehicle for transmitting drive force to the rear wheels. The clutch control device includes a dog clutch and a friction clutch, and a controller that controls the engagement and disengagement of the dog clutch and the friction clutch. In this clutch control device, the four-wheel drive hybrid vehicle includes a disconnected, two-wheel drive mode and a connected, four-wheel drive mode. When a driver's foot is lifted off an accelerator in a low-speed region when the connected, four-wheel drive mode is selected, the 4WD control unit maintains the connected, four-wheel drive mode while the brakes are not depressed, and shifts the mode to the disconnected, two-wheel drive mode when the brakes are depressed.

Abstract: A drive force distributing device includes first and second rollers rotatable jointly with main a drive wheel system and a subordinate drive wheel system, respectively. Control of the drive force distribution between the main drive wheels and the subordinate drive wheels is performed by adjusting an inter-roller pressing force. A structural body suppresses turning of one of the first and second rollers at a predetermined position. A reference position setting mechanism turns either one of the first and second rollers to turn in one direction, detects a position at which the turn is suppressed by the structural body, and sets a reference position based on the detected position. A turning amount of one of the first and second rollers is detected with respect to the reference position set by the reference position setting mechanism and the control of drive force distributing is performed based on the detected turning amount.

Abstract: A drive force distributing device includes first and second rollers rotatable jointly with main a drive wheel system and a subordinate drive wheel system, respectively. Control of the drive force distribution between the main drive wheels and the subordinate drive wheels is performed by adjusting an inter-roller pressing force. A structural body suppresses turning of one of the first and second rollers at a predetermined position. A reference position setting mechanism turns either one of the first and second rollers to turn in one direction, detects a position at which the turn is suppressed by the structural body, and sets a reference position based on the detected position. A turning amount of one of the first and second rollers is detected with respect to the reference position set by the reference position setting mechanism and the control of drive force distributing is performed based on the detected turning amount.

Abstract: A drive force distributing apparatus includes a first roller that is rotatable with a main drive wheel system and a second roller that is rotatable with a subordinate drive wheel system. Control of the drive force distribution between the main drive wheel system and the subordinate drive wheel system is carried out by turning the second roller by the rotation of a crankshaft to thereby adjust a radial pressing force of the second roller against the first roller. A bearing support includes an exterior wall disposed in a housing, a first through bore formed in the exterior wall for receiving a shaft portion of the first roller, a first interior side wall extending radially outward from the first through bore, a second through bore formed in the exterior wall for receiving a crankshaft, and a second interior side wall extending radially outward from the second through bore.

Abstract: A drive force distributing apparatus includes a first roller that is rotatable with a main drive wheel system and a second roller that is rotatable with a subordinate drive wheel system. Control of the drive force distribution between the main drive wheel system and the subordinate drive wheel system is carried out by turning the second roller by the rotation of a crankshaft to thereby adjust a radial pressing force of the second roller against the first roller by an adjustment mechanism. The adjustment mechanism includes a pinion shaft in meshed engagement with the crankshaft, a first output gear fitted to the pinion shaft, and a second output gear meshed with the first output gear and driven to rotate by a motor. A rotation angle sensor is provided to detect a variation in teeth of the first output gear to detect a rotation angle of the first output gear, whereby control of the drive force distribution is performed based on the detected rotation angle of the first output gear.

Abstract: A driving force distribution apparatus is provided that includes a first roller rotatable together with a main wheel transmission system associated with main drive wheels and a second roller rotatable together with a subordinate driving wheel transmission system associated with subordinate drive wheels. A driving force distribution is enabled to the subordinate drive wheels by adjusting the radial pressing force between the first roller and the second roller through a revolution of the second roller using a power of an inter-roller radial pressing force generating source to thereby control the driving force distribution between the main driving wheels and subordinate driving wheels. Further, an electromagnetic brake is provided that, when energized and supplied with current, generates a braking force to hold the revolution position of the second roller. When de-energized, no braking force will be produced so that the revolution of the second roller will be allowed.

Abstract: An exhaust manifold connected to exhaust ports of at least three straightly-arranged cylinders of an internal combustion engine is constructed by a primary exhaust pipe which extends from the foremost cylinder of the cylinders in the rearward direction of the engine along the direction of the straight arrangement of the cylinders and a plurality of secondary exhaust pipes which extend from the other cylinders except for the foremost cylinder to the primary exhaust pipe. The secondary exhaust pipes are collected to the primary exhaust pipe so that downstream end portions of the secondary exhaust pipes are wound into the center axis of the primary exhaust pipe at a plurality of points on the center axis, respectively.

Abstract: A plurality of upstream main exhaust passages extend from cylinders of an engine. A downstream main exhaust passage is connected to the upstream main exhaust passages. A main catalytic converter is mounted in the downstream main exhaust passage. A plurality of upstream bypass exhaust passages extend from the upstream main exhaust passages. Each upstream bypass exhaust passage has a sectional area smaller than that of the corresponding upstream main exhaust passage. A downstream bypass exhaust passage is connected to the upstream bypass exhaust passages and has a downstream end connected to the downstream main exhaust passage at a position upstream of the main catalytic converter. An auxiliary catalytic converter is mounted in the downstream bypass exhaust passage. A gas flow switching device is provided which is capable of forcing the exhaust gas from the cylinders of the engine to flow toward the upstream bypass exhaust passages when assuming a given operation position.

Abstract: An exhaust manifold connected to exhaust ports of at least three straightly-arranged cylinders of an internal combustion engine is constructed by a primary exhaust pipe which extends from the foremost cylinder of the cylinders in the rearward direction of the engine along the direction of the straight arrangement of the cylinders and a plurality of secondary exhaust pipes which extend from the other cylinders except for the foremost cylinder to the primary exhaust pipe. The secondary exhaust pipes are collected to the primary exhaust pipe so that downstream end portions of the secondary exhaust pipes are wound into the center axis of the primary exhaust pipe at a plurality of points on the center axis, respectively.

Abstract: An exhaust manifold connected to exhaust ports of at least three straightly-arranged cylinders of an internal combustion engine is constructed by a primary exhaust pipe which extends from the foremost cylinder of the cylinders in the rearward direction of the engine along the direction of the straight arrangement of the cylinders and a plurality of secondary exhaust pipes which extend from the other cylinders except for the foremost cylinder to the primary exhaust pipe. The secondary exhaust pipes are collected to the primary exhaust pipe so that downstream end portions of the secondary exhaust pipes are wound into the center axis of the primary exhaust pipe at a plurality of points on the center axis, respectively.

Abstract: An exhaust system for an internal combustion engine includes a catalytic device within an exhaust path of the engine, wherein the catalytic device includes a housing with a catalyst carrier. A length of the catalyst carrier along a longitudinal axis, measured along a downstream flow direction of exhaust gas within the exhaust path, is substantially the same or a shorter than the upstream distance traveled by a reverse flow of exhaust gas during an exhaust gas pulsation within the housing. With this type of configuration, due to reciprocating movements of the exhaust gas caused by the pulsations, the same exhaust gas passes through the catalyst carrier multiple times. Thus, an increased number of heat exchanges take place within the catalyst carrier, which rapidly increases the catalyst temperature after a cold engine start.

Abstract: An intake control valve of an intake device of an internal combustion engine comprises a given portion defined by an air intake passage that leads to a combustion chamber of the engine through an intake valve; a pivot shaft passing through the given portion; and a valve plate secured to the pivot shaft to pivot therewith within the given portion. The valve plate is pivotal between a close position to close the air intake passage and an open position to open the air intake passage. When the valve plate assumes the close position, the interior of the air intake passage downstream the valve plate is formed with mutually isolated first and second air flows that are separated and oriented to enhance a flow of air/fuel mixture in the combustion chamber.

Abstract: A hydrocarbon trapping layer (25) is formed by coating a hydrocarbon trapping material onto a carrier (21A). A number of exhaust gas passages (34) are formed in the carrier (21A) and a plurality of slits (22) are formed on the carrier (21A) to cross the passages (24) in a transverse orientation. The slits (22) delay temperature increases in the downstream hydrocarbon trapping layer (25) and delay the release of trapped hydrocarbons therefrom. This is due to blocking the transmission of heat to the downstream hydrocarbon trapping layer (25) from the upstream hydrocarbon trapping layer (25). The slits (22) further produce a turbulent flow in the flow of exhaust gas and promote diffusion of exhaust gas over the entire surface of the carrier (21A).

Abstract: An air intake structure is provided with an air intake control valve disposed in the air intake passage. The air intake control valve has a valve element pivotally mounted at one end adjacent to a passage wall of the air intake passage. The air intake control valve is configured to control a gas flow based on the rotational position of the valve element. At least one horizontal partitioning plate extends along the flow direction of an intake air. The horizontal partitioning plate can be stationary or moveable with the valve element. Optionally, the valve element has a swirl-producing notch and a vertical partitioning plate extends substantially perpendicular to the horizontal partitioning plate from a position corresponding to a vertical side edge of the swirl-producing notch when the air intake control valve is fully closed. The vertical partitioning plate can be stationary or moveable with the valve element.

Abstract: A catalytic converter is interposed in an exhaust passage of an internal combustion engine. In the converter, a plurality of carriers are disposed in series with gaps. Each carrier comprises a hydrocarbon trapping layer, a three-way catalyst layer and a number of passages facing the three-way catalyst layer. The gaps interrupts heat transfer between the carriers in order to retard temperature increase in the hydrocarbon trapping layer and promotes a turbulence in exhaust gas flow in the converter in order to homogenize the exhaust gas dispersion in a radial direction, thereby enhancing the hydrocarbon purification performance of the converter.

Abstract: An intake control valve of an intake device of an internal combustion engine comprises a given portion defined by an air intake passage that leads to a combustion chamber of the engine through an intake valve; a pivot shaft passing through the given portion; and a valve plate secured to the pivot shaft to pivot therewith within the given portion. The valve plate is pivotal between a close position to close the air intake passage and an open position to open the air intake passage. When the valve plate assumes the close position, the interior of the air intake passage downstream the valve plate is formed with mutually isolated first and second air flows that are separated and oriented to enhance a flow of air/fuel mixture in the combustion chamber.

Abstract: A spark plug system includes a center spark plug and a plurality of peripheral spark plugs, the spark plugs extending into a ridge-roof type combustion chamber of an internal combustion engine from the inner surface of a cylinder head and being disposed approximately on the ridgeline of the ridge-roof. The amount by which the center plug projects into the combustion chamber from the inner surface of the cylinder head is different from the amount by which each of the peripheral plugs projects into the combustion chamber from the inner surface of the cylinder head, whereby the time in which the flame propagation of the center plug reaches the flame propagation of the peripheral plugs is delayed.

Abstract: An internal combustion engine that includes a cylinder block formed with a cylinder bore, a cylinder head operatively connected to the cylinder block; a piston slidably disposed in the cylinder bore to define a combustion chamber; an engine front side squish area and a rear side squish area where the engine front and rear side squish areas include narrow gaps formed between a cylinder head and the piston is disclosed. The engine front side squish area and the engine rear side squish area generate a squish flow in the combustion chamber in response to the piston moving within the cylinder bore. Engine front and rear side igniter plugs are also provided that each include a pair of electrodes placed adjacent the respective engine front and rear side squish areas so that squish flow may pass through an igniter gap defined between the pairs of electrodes of the front and rear side igniter plugs.

Abstract: An air intake structure is provided with an air intake control valve disposed in the air intake passage. The air intake control valve has a valve element pivotally mounted at one end adjacent to a passage wall of the air intake passage. The air intake control valve is configured to control a gas flow based on the rotational position of the valve element. A horizontal partitioning plate extends along the flow direction of an intake air. The horizontal partitioning plate can be stationary or moveable with the valve element. The valve element has a swirl-producing notch and a vertical partitioning plate extends substantially perpendicular to the horizontal partitioning plate from a position corresponding to a vertical side edge of the swirl-producing notch when the air intake control valve is fully closed. The vertical partitioning plate can be stationary or moveable with the valve element.

Abstract: An internal combustion engine that includes a cylinder block formed with a cylinder bore, a cylinder head operatively connected to the cylinder block; a piston slidably disposed in the cylinder bore to define a combustion chamber; an engine front side squish area and a rear side squish area where the engine front and rear side squish areas include narrow gaps formed between a cylinder head and the piston is disclosed. The engine front side squish area and the engine rear side squish area generate a squish flow in the combustion chamber in response to the piston moving within the cylinder bore. Engine front and rear side igniter plugs are also provided that each include a pair of electrodes placed adjacent the respective engine front and rear side squish areas so that squish flow may pass through an igniter gap defined between the pairs of electrodes of the front and rear side igniter plugs.