Abstract: In an air intake system (14) for internal combustion engines in which combustion air is led into a cylinder via an air inlet path, the air inlet path comprises a double structure of a main inlet path (7a) and a sub inlet path (8a) that the sub inlet path (8a) is placed in the main inlet path (7a) so as to be in close contact with a bottom wall of the main inlet path (7a), a downstream end of the sub inlet path (8a) being positioned near an inlet valve opening (10e) on its one side other than an exhaust valve opening (10d) side; and that an opening/closing valve (9) is disposed within the sub inlet path (8a), wherein the opening/closing valve (9) is closed in a low intake-air amount operating region of the engine so as to allow intake air to be biased from the main inlet path (7a) toward a center of the cylinder and to flow into the cylinder along a cylinder axis.

Abstract: Herein disclosed is a cooling system for use with an internal combustion engine which is operated on evaporable fuel supplied from a fuel tank. The cooling system comprises a tube extending from the fuel tank to a venturi throat portion of an air induction passage of the engine, an expansion valve connected to the tube and opening the tube when a pressure in the tube downstream of the valve is reduced to a certain degree, an evaporator device connected to the tube at a position downstream of the expansion valve, and a structure for defining an enclosed space about the evaporator device.

Abstract: A cylinder block for an internal combustion engine includes the skeleton frame formed of metal and a waterjacket surrounding the frame formed of a heat resistant plastic. The engine includes a cylinder head and the cylinder bearing supports and a sleeve forming a cylinder bore. The engine block, cylinder head and main bearings are fixed together with bolts which pass through portions of the framework parallel to the metal sleeve. The engine also includes an air intake pipe with the portion of the pipe adjacent the waterjacket integrally formed with the waterjacket.

Abstract: The crankshaft of an internal combustion engine is supported in a split bearing assembly near one end of the crankshaft, with the lower half of the bearing assembly formed in a bearing holder secured to the engine block. An arcuate flange projects axially towards that end of the crankshaft. The flange underlies a crankshaft pulley which drives a timing belt. The arcuate surface of the flange is struck from a center offset from the crankshaft axis in order to provide clearance for the timing belt. The offset construction also improves the joint seal between the oil pan and the engine block.

Abstract: A pump for lubricating oil is mounted on the outer face of the end wall of an internal combustion engine. An oil filter is mounted on a side wall of the engine parallel to the crankshaft, and a substantially straight sub-gallery in the side wall connects the oil pump to the oil filter. A substantially main gallery receives lubricating oil from the oil filter and delivers it to branched oil supply passages to lubricate parts of the engine.

Abstract: An improved intake manifold structure for internal combustion engines includes a distribution chamber having an upper sub-chamber leading to a carburetor and a lower sub-chamber communicating with the upper sub-chamber through a communication hole. A plurality of branch passages extend from the lower sub-chamber to a plurality of combustion chambers. An air-fuel mixture fed from the carburetor to the distribution chamber is expanded successively in two steps to promote its atomization as it passes through the two sub-chambers, thus improving uniform distribution of the mixture to the respective branch passages. Engine exhaust gas is returned to the upper sub-chamber to further promote the atomization of the mixture.

Abstract: A variable-displacement rotary fluid compressor comprising first and second rotary compressor assemblies including respective rotor units rotatable about axes aligned with each other and first and second drive shafts respectively carrying and rotatable with the rotor units, each of the compressor assemblies having fluid inlet and outlet ports; a fluid inlet chamber communicating with the fluid inlet ports of the two compressor assemblies and a fluid outlet chamber communicating with the fluid outlet ports of the compressor assemblies; a first clutch assembly comprising a drive member which is rotatable about an axis aligned with the axes of rotation of the rotor units and which is to be driven by a drive source, a driven member rotatable with the first drive shaft and coupling means to couple the drive and driven members together when actuated; and a second clutch assembly comprising a driven member rotatable with the second drive shaft and coupling means to couple the respective driven members of the first a

Abstract: A lubricating system of an internal combustion engine is equipped with intake and exhaust valves and a valve operating mechanism having rotating portions and reciprocating portions. The rotating portions are communicated with an oil pump via a first oil path and the reciprocating portions are also communicated with the oil pump via a second oil path. The rotating portions have a cam shaft in operative connection with a crank shaft. The reciprocating portions include a rocker follower pivoted to a follower shaft and engaging the cam shaft, a rocker arm pivoted to a rocker shaft and operatively connected to the intake or exhaust valve, and a push rod connecting the rocker follower and rocker arm. A series feed oil path is defined in the follower shaft, rocker follower, push rod, rocker arm and rocker shaft so as to pass through their mutual contact portions, and is communicated with the oil pump via the second oil path.

Abstract: A V-type internal combustion engine has a timing gear mechanism positioned in front of the cylinder block for driving the camshaft from the crankshaft. A coolant pump is secured to the cylinder block laterally offset from the crankshaft and adjacent one bank of cylinders. A first discharge passage leads from the coolant pump to the adjacent bank of cylinders and the second discharge passage is formed on a cover for the timing gear mechanism for supplying coolant to the remote bank of cylinders.

Abstract: Two shiftable bus bar unit point sections are simultaneously shifted to allow one of the sections to align with a stationary bus bar unit point section. A coupler slides on the stationary point section toward the just aligned one of the shiftable point sections to couple the same with the stationary point section. The shifting of the shiftable point sections and the sliding of the coupler are controlled by an operating mechanism which employs a cam. A holding device covers sealingly the electrically dangerous exposed end of the other of the shiftable point sections.

Abstract: The present invention discloses an apparatus for cooling engine oil characterized in that there is provided an oil reservoir in communication with a first oil pump of an internal combustion engine. Further, an oil passage connects the pump to the oil reservoir, and the oil passage is provided with a by-pass passage in parallel with the oil passage. In the by-pass passage there is disposed an oil cooler on the upstream side and a second oil pump on the downstream side, the second pump also in communication with said oil reservoir.

Abstract: A bus bar unit on which a current collecting unit rides comprises a body having therein a groove and thereon a hinged lid portion which closes the groove when pressed against the body proper, and a current carrying naked cable received in the groove. The current collecting unit comprises a shoe, a horizontal roller for continuously opening the lid portion to allow the shoe to be in sliding contact with the naked cable when moved in a direction, and a vertical roller for pressing the opened lid portion against the body proper to close the groove when moved in the direction. The shoe has a tapered section having an inclined side upon which a back surface of the lid portion bears to cause raising of the lid portion from the body proper when the shoe moves in the direction under a state in which the lid portion is disengaged from the horizontal roller.

Abstract: A shifting mechanism for power transmission device in an automotive vehicles, wherein, when gear shifting of the fifth or third speed gear and the reverse gear is to be done by reciprocating movement of a fifth speed fork shaft, an engaging or control pin of the shift fork shaft is permitted to move at the time of the fifth speed gear shifting by forming an L-shaped control slot in a shift lever, thereby avoiding undesirable influence on the shifting mechanism of a reverse idle gear.