Steel piston with counter-bore design

Patent metadata

Field	Value
Publication number	US-9291120-B2
Application number	US-201314030530-A
Country	US
Kind code	B2
Filing date	Sep 18, 2013
Priority date	Sep 18, 2012
Publication date	Mar 22, 2016
Grant date	Mar 22, 2016

Abstract

A piston for an internal combustion engine is provided. The piston includes a piston body which is made of steel. The piston body has a crown portion with an upper combustion surface, a pair of skirts which depend from the crown surface, a pair of pin bosses for receiving a wrist pin and a plurality of pin boss bridges which extend from the pin bosses to the skirts. Each of the pin boss bridges extends axially to a lower end which is opposite of the crown portion and has a rib with an increased thickness at its lower end. At least one of the pin boss bridges has a generally flat counter-bore surface for providing a reference location for machining of the piston body.

First claim

What is claimed is:

1. A piston for an internal combustion engine, comprising:
a piston body made of steel;
said piston body having a crown portion with an upper combustion surface, a pair of skirts depending from said crown portion and extending axially to lower skirt ends, a pair of pin bosses for receiving a wrist pin, and a plurality of pin boss bridges which extend from said pin bosses to said skirts;
each of said pin boss bridges extending axially to a lower pin boss bridge end which presents a rib and wherein each rib has an increased wall thickness relative to a longitudinally adjacent portion of said pin boss bridge; and
at least one of said pin boss bridges having a generally flat counter-bore surface which is spaced longitudinally above said lower skirt ends and lower pin boss ends for providing a reference location for machining of said piston body.

2. The piston as set forth in claim 1 wherein each of said skirts has a generally continuous wall thickness from said crown portion to said lower skirt end.

3. The piston as set forth in claim 1 wherein said piston body is made of one integral piece of steel.

4. The piston as set forth in claim 1 wherein said crown portion includes a ring belt with a plurality of axially spaced ring grooves for receiving a plurality of piston rings.

5. The piston as set forth in claim 4 further including an oil drainage groove spaced axially from said ring grooves.

Assignees

• Federal Mogul Corp

Inventors

• Matsuo Eduardo
• Martins Airton

Classifications

• F02F2200/00

  Manufacturing · CPC title

• F02F3/0015 Primary

  Multi-part pistons · CPC title

• F02F3/0084

  the pistons being constructed from specific materials · CPC title

• Y10T29/49249

  Piston making · CPC title

• F05C2201/0448

  Steel · CPC title