Piston with enhanced cooling gallery

A piston for an internal combustion engine, comprising:

• a body with a cylindrical outer surface with an annular uppermost ring groove and a lowermost ring groove extending into said outer surface, said outer surface being free of any ring grooves between said uppermost and lowermost ring grooves, and a top land extending from said uppermost ring groove to an upper combustion surface having a combustion bowl recessed therein, said body having a pair of pin bosses with pin bores aligned with one another along a pin bore axis, said pin bosses having radially outwardly, oppositely facing surfaces generally aligned axially with said cylindrical outer surface of said body;
• a first piston ring disposed in said uppermost ring groove;
• said first piston ring being L-shaped with a vertically extending leg that is flush with said upper combustion surface of said body;
• a second piston ring disposed in said lowermost ring groove;
• said body having an annular sealed cooling gallery with a cooling medium disposed and sealed therein, said sealed cooling gallery extending between said first and second piston rings;
• wherein said uppermost ring groove has a lowermost surface and said lowermost ring groove has an uppermost surface, said sealed cooling gallery has an uppermost surface and a lowermost surface, said uppermost surface of said sealed cooling gallery being substantially radially aligned with said lowermost surface of said uppermost ring groove and said lowermost surface of said sealed cooling gallery being substantially radially aligned with said uppermost surface of said lowermost ring groove;
• and
• wherein said annular sealed cooling gallery extends radially inwardly and directly underneath a portion of said combustion bowl.

A piston for an internal combustion engine, comprising:

• a body with a cylindrical outer surface with an annular uppermost ring groove and an annular lowermost ring groove, and a top land extending from said uppermost ring groove to an upper combustion surface having a combustion bowl recessed therein, said body having a pair of pin bosses with pin bores aligned with one another along a pin bore axis;
• a first piston ring disposed in said uppermost ring groove;
• said first piston ring being L-shaped with a vertically extending leg that is flush with said upper combustion surface of said body;
• a second piston ring disposed in said lowermost ring groove;
• said body having an annular sealed cooling gallery with a cooling medium disposed and sealed therein, said sealed cooling gallery extending in radial alignment with said uppermost ring groove and extending below said lowermost ring groove and having generally the same shape as viewed both in cross-section looking along said pin bore axis and looking generally transverse to said pin bore axis;
• wherein said annular sealed cooling gallery extends radially inwardly and directly underneath a portion of said combustion bowl;
• and
• said annular sealed cooling gallery having an uppermost surface that is radially aligned with a portion of said uppermost ring groove.

A piston for an internal combustion engine, comprising:

• a body with a cylindrical outer surface with an annular uppermost ring groove and an annular lowermost ring groove extending into said outer surface, said cylindrical outer surface being free of any ring grooves between said uppermost and lowermost ring grooves, and a top land extending from said uppermost ring groove to an upper combustion surface, said top land being recessed radially inwardly from said cylindrical outer surface, said body having a pair of pin bosses with pin bores aligned with one another along a pin bore axis;
• a generally L-shaped first piston ring having a first portion configured for receipt in said uppermost ring groove and a second portion configured to extend upwardly from said uppermost ring groove along said top land to a top that is flush with said upper combustion surface of said body;
• a second piston ring disposed in said lowermost ring groove;
• said upper combustion surface having a combustion bowl depending therein, said combustion bowl having an annular lowermost valley and a raised peak, said annular lowermost valley extending below said annular uppermost ring groove;
• said body having an annular sealed cooling gallery with a cooling medium disposed and sealed therein, said sealed cooling gallery having an uppermost surface extending above said annular lowermost valley of said combustion bowl and having a lowermost surface extending below said annular lowermost valley;
• wherein said annular sealed cooling gallery extends radially inwardly and directly underneath a portion of said combustion bowl;
• and
• wherein said uppermost surface of said sealed cooling gallery is radially aligned with a portion of said uppermost ring groove.