Abstract: An engine oil receiving structure comprises a vertically disposed crank shaft, a laterally movable piston, a connecting rod connecting the crank shaft and the piston, a cylinder barrel housing the crank shaft and the piston, a crank case containing the crank shaft together with the cylinder barrel, a cylinder head forming a combustion chamber, the combustion chamber connecting to a piston movable part end face of the cylinder barrel, an oil filter filtering engine lubricant, and an oil case storing oil flowing out when the oil filter is removed from a mounted position, and the oil case is fixed to an engine under the oil filter, and comprises a discharge path to discharge the stored oil.

Abstract: An internal combustion engine includes a supercharger, an oil tank, a scavenging pump, a first passage, a second passage, and a one-way valve. The supercharger is provided in an intake passage. The oil tank communicates with a crankcase via a collecting passage. The scavenging pump is provided in the collecting passage to transport a fluid in the crankcase to the oil tank. The first passage connects an upper space located above a liquid surface in the oil tank and a downstream portion of the intake passage located on a downstream side with respect to the supercharger. The second passage connects the upper space and an upstream portion of the intake passage located on an upstream side with respect to the supercharger. The one-way valve is provided in the first passage and allows the fluid to flow only from the upper space toward the intake passage.

Abstract: An internal combustion engine includes a supercharger, an oil tank, a scavenging pump, a first passage, a second passage, and a one-way valve. The supercharger is provided in an intake passage. The oil tank communicates with a crankcase via a collecting passage. The scavenging pump is provided in the collecting passage to transport a fluid in the crankcase to the oil tank. The first passage connects an upper space located above a liquid surface in the oil tank and a downstream portion of the intake passage located on a downstream side with respect to the supercharger. The second passage connects the upper space and an upstream portion of the intake passage located on an upstream side with respect to the supercharger. The one-way valve is provided in the first passage and allows the fluid to flow only from the upper space toward the intake passage.

Abstract: A water-jacket structure, for a water-cooled internal combustion engine, forms a cylinder block water jacket in a cylinder block so as to surround cylinder bores formed in the cylinder block to make cooling water flow through the cylinder block water jacket into a cylinder head water jacket formed in a cylinder head joined to the cylinder block. An upper connecting opening is formed in an upper part of the cylinder block water jacket so as to open into the cylinder head water jacket. In the cylinder block is formed a lower connecting passage opening into a lower part of the cylinder block water jacket, extending upward, and connecting to the cylinder head water jacket.

Abstract: An oil pan is disposed in a lower part of an internal combustion engine and has an oil pan body divided, with respect to a vertical direction, into oil pan elements having bottom walls respectively of different depths. A baffle plate divides the interior of the oil pan body into a plurality of spaces at the boundary of adjacent ones of the bottom walls to regulate the flow of oil between the adjacent ones of spaces. The baffle plate is divided with respect to a vertical direction into a plurality of baffle plate elements. The baffle plate elements are formed integrally with the oil pan elements, respectively. The oil pan for an internal combustion engine can be manufactured by reduced time and reduced labor at a low manufacturing cost.

Abstract: A water-jacket structure, for a water-cooled internal combustion engine, forms a cylinder block water jacket in a cylinder block so as to surround cylinder bores formed in the cylinder block to make cooling water flow through the cylinder block water jacket into a cylinder head water jacket formed in a cylinder head joined to the cylinder block. An upper connecting opening is formed in an upper part of the cylinder block water jacket so as to open into the cylinder head water jacket. In the cylinder block is formed a lower connecting passage opening into a lower part of the cylinder block water jacket, extending upward, and connecting to the cylinder head water jacket.

Abstract: An oil pan is disposed in a lower part of an internal combustion engine and has an oil pan body divided, with respect to a vertical direction, into oil pan elements having bottom walls respectively of different depths. A baffle plate divides the interior of the oil pan body into a plurality of spaces at the boundary of adjacent ones of the bottom walls to regulate the flow of oil between the adjacent ones of spaces. The baffle plate is divided with respect to a vertical direction into a plurality of baffle plate elements. The baffle plate elements are formed integrally with the oil pan elements, respectively. The oil pan for an internal combustion engine can be manufactured by reduced time and reduced labor at a low manufacturing cost.

Abstract: A control system for an internal combustion engine having a plurality of cylinders and a switching mechanism for switching between an all-cylinder operation in which all of the plurality of cylinders are operated and a partial-cylinder operation in which at least one of the plurality of cylinders is halted. A condition for performing the partial-cylinder operation is determined, based on the detected operating parameters of the vehicle driven by the engine. A result of the determination is modified so that the partial-cylinder operation may be continued, when the detected operating parameters satisfy a predetermined continuation condition within a predetermined time period from the time a vehicle operating state where the condition for performing the partial-cylinder operation is satisfied, has changed to another vehicle operating state where the condition for performing the partial-cylinder operation is not satisfied.

Abstract: A control system for an internal combustion engine having a plurality of cylinders and a switching mechanism for switching between an all-cylinder operation in which all of the plurality of cylinders are operated and a partial-cylinder operation in which at least one of the plurality of cylinders is halted. A condition for performing the partial-cylinder operation is determined, based on the detected operating parameters of the vehicle driven by the engine. A result of the determination is modified so that the partial-cylinder operation may be continued, when the detected operating parameters satisfy a predetermined continuation condition within a predetermined time period from the time a vehicle operating state where the condition for performing the partial-cylinder operation is satisfied, has changed to another vehicle operating state where the condition for performing the partial-cylinder operation is not satisfied.

Abstract: A control system for an internal combustion engine having a plurality of cylinders and a switching mechanism for switching between an all-cylinder operation in which all of the plurality of cylinders are operated and a partial-cylinder operation in which at least one of the plurality of cylinders is halted. A condition for performing the partial-cylinder operation is determined, based on the detected operating parameters of the vehicle driven by the engine. A result of the determination is modified so that the partial-cylinder operation may be continued, when the detected operating parameters satisfy a predetermined continuation condition within a predetermined time period from the time a vehicle operating state where the condition for performing the partial-cylinder operation is satisfied, has changed to another vehicle operating state where the condition for performing the partial-cylinder operation is not satisfied.

Abstract: A knock control system for an internal combustion engine having a plurality of cylinders. Operation of the engine is switchable between a partial-cylinder operation for operating some of the cylinders and an all-cylinder operation for operating all of the cylinders. A determination threshold for determining knocking is set according to an output signal from the knock sensor. A level of the output signal from the knock sensor is compared with the determination threshold, and occurrence of knocking is determined according to a result of the comparison. The determination threshold used during the partial-cylinder operation is set to a value less than a value of the determination threshold used during the all-cylinder operation.

Abstract: A control system for an internal combustion engine having a plurality of cylinders and a switching mechanism for switching between an all-cylinder operation in which all of the plurality of cylinders are operated and a partial-cylinder operation in which at least one of the plurality of cylinders is halted. A condition for performing the partial-cylinder operation is determined, based on the detected operating parameters of the vehicle driven by the engine. A result of the determination is modified so that the partial-cylinder operation may be continued, when the detected operating parameters satisfy a predetermined continuation condition within a predetermined time period from the time a vehicle operating state where the condition for performing the partial-cylinder operation is satisfied, has changed to another vehicle operating state where the condition for performing the partial-cylinder operation is not satisfied.

Abstract: A knock control system for an internal combustion engine having a plurality of cylinders. Operation of the engine is switchable between a partial-cylinder operation for operating some of the cylinders and an all-cylinder operation for operating all of the cylinders. A determination threshold for determining knocking is set according to an output signal from the knock sensor. A level of the output signal from the knock sensor is compared with the determination threshold, and occurrence of knocking is determined according to a result of the comparison. The determination threshold used during the partial-cylinder operation is set to a value less than a value of the determination threshold used during the all-cylinder operation.

Abstract: In an intake port structure in an internal combustion engine, an edge portion is formed on a lower surface of an intake port at a location immediately upstream of an intake bore 7. The angle .theta. formed by the center line L of the intake port with respect to a deck surface is set smaller than the angle .theta..sub. formed by an exhaust valve seat provided in a pent roof of a combustion chamber with respect to the deck surface. Further, if the height of an apex of the pent roof of the combustion chamber is represented by H.sub.0, and an intersection between an extension of the center line L of the intake port 5 and a straight vertical line L.sub.0 passing through the apex of the pent roof of the combustion chamber to intersect the deck surface at a right angle is represented by P, the height H of the intersection P is set so that a relation, H.sub.0 >H>2H.sub.0 /3 is satisfied.

Abstract: 1,4-Dihydropyridine compound having the general formula: ##STR1## wherein R and R' are independently a methyl, ethyl, or propyl group. This compound has a remarkable liver protective action and a low toxicity.