Piston having baffle ring for limiting abnormal combustion and piston and cylinder liner assembly
AssigneeCaterpillar Inc.
InventorSiddhesh Bharat Bhoite
Life of this patent
Estimating the term…
Abstract
A piston in a piston and cylinder liner assembly for an internal combustion engine includes a piston crown, and a plurality of piston rings seated within a plurality of ring grooves in a crown outer surface. The plurality of piston rings includes a baffle ring seated within an uppermost ring groove. A plurality of pressure balancing passages extend through the piston crown each from a first opening formed in an uppermost land to a second opening formed in a second land. The baffle ring may be a non-loaded ring structured to prevent oil droplets from entering a cylinder and causing abnormal combustion. In an embodiment, a shielding wall projects axially from an annular rim of the piston to prevent entry of oil not deflected by the baffle ring.
Claims20
A piston comprising:
- a piston crown defining a piston center axis, and including an annular rim extending circumferentially around a combustion bowl, and a crown outer surface having a plurality of ring grooves including an uppermost ring groove formed therein;
- a plurality of piston rings seated within the plurality of ring grooves and including a baffle ring seated within the uppermost ring groove;
- the crown outer surface further including an uppermost land and a second land, and the uppermost ring groove is formed axially between the uppermost land and the second land;
- and
- the piston crown further including a plurality of pressure balancing passages having a circumferential distribution around the piston center axis, and each extending through the piston crown from a first opening formed in the uppermost land to a second opening formed in the second land.
A piston for an internal combustion engine comprising:
- a piston crown defining a piston center axis, and including an annular rim extending circumferentially around a combustion bowl, and a crown outer surface having formed therein each of an uppermost ring groove, a scraper ring groove, a compression ring groove, and an oil ring groove;
- the crown outer surface further including an uppermost land and a second land, and the uppermost ring groove is formed axially between the uppermost land and the second land;
- and
- the piston crown further including a plurality of pressure balancing passages, and each extending through the piston crown from a first opening formed in the top land to a second opening formed in the second land.
A piston and cylinder liner assembly comprising:
- a cylinder liner;
- a piston positioned in the cylinder liner and defining a piston center axis, the piston including an annular rim extending circumferentially around a combustion bowl, and a plurality of piston rings including an uppermost baffle ring, a scraper ring, a compression ring, and a lowermost oil ring;
- the baffle ring including a non-loaded ring, and each of the scraper ring, the compression ring, and the oil ring included a loaded ring;
- and
- the piston further including a pressure balancing passage formed therein and fluidly connecting from a location axially above the baffle ring to a location axially below the baffle ring.
Dependencies are inferred from the claim text.