摘要:
A piston for diesel engine applications has a piston body cast entirely of one piece of steel and includes a piston head with a combustion bowl, a ring belt and an oil cooling gallery. A pair of pin bosses and a piston skirt are cast as one piece with the piston head out of the same steel material.
摘要:
An end part of a piston (5) on a front edge side is formed so as to have a crowning of a 1.2-order to 2.5-order curve where a length is 10% or more and 80% or less of a length of a cylindrical part (20) and a height is 10% or more and 160% or less of a clearance. An end part of the piston (5) on a rear edge side is formed so as to have a crowning of a 1.2-order to 2.5-order curve where a length is 10% or more and 60% or less of the length of the cylindrical part (20) and a height is 10% or more and 160% or less of the clearance. An end part of a cylinder block (3) on a front edge side is formed so as to have a crowning of a 1.2-order to 2.5-order curve where a length is 8% or more and 60% or less of the length of a cylindrical part (20) and a height is 12% or more and 125% or less of the clearance.
摘要:
A piston is provided in which the amount of uncombusted and discharged air-fuel mixture is small, and agglutination of a piston ring due to heat is prevented. In a piston 2 in which plural peripheral grooves in which piston rings are provided are formed in an outer peripheral surface, as the relation between an inner diameter B of a cylinder 1 and a distance L between an upper surface of the piston and an upper surface of a top peripheral groove 4a, L/B ≤ 0.1 holds. A cooling chamber 5a is formed in close vicinity to the top peripheral groove. A dead volume S partitioned with the piston, a cylinder liner 11 and a top piston ring 3a is reduced, and the amount of air-fuel mixture enclosed here and discharged in uncombusted state is reduced. Further, agglutination of the top piston ring to the cylinder due to thermal load can be prevented with the cooling chamber 5a. The thermal efficiency as an engine is improved in comparison with conventional art.
摘要:
A piston for diesel engine applications has a piston body cast entirely of one piece of steel and includes a piston head with a combustion bowl, a ring belt and an oil cooling gallery. A pair of pin bosses and a piston skirt are cast as one piece with the piston head out of the same steel material.
摘要:
A monobloc piston assembly has at least two parts fixedly joined together forming a piston body having an oil cooling gallery. The oil cooling gallery is defined by an upper wall, a lower wall, and a pair of radially spaced inner and outer annular walls. A skirt is formed as one piece and of the same material with at least one of the two parts and depends generally along a longitudinal axis from the lower wall. A pair of pin bosses are spaced laterally from the longitudinal axis and depend generally from the lower wall. At least one elongated opening extends generally between the pin bosses with the opening preferably spanning a substantial portion of the distance between the pin bosses. Oil flows into and out of an oil cooling gallery through the opening.