Piston for an internal combustion engine and method for producing said piston

Patent metadata

Field	Value
Publication number	US-2018179986-A1
Application number	US-201615389521-A
Country	US
Kind code	A1
Filing date	Dec 23, 2016
Priority date	Dec 23, 2016
Publication date	Jun 28, 2018
Grant date	—

Abstract

A piston including a piston crown, the piston crown defining a combustion bowl with a bowl base and bottom surface. A failure initiation structure is provided on the bottom surface of the combustion bowl to initiate favorable fracture at predetermined loads. Such favorable fracture may lead to the a separation of a fragment of the bowl base from the combustion bowl when a predetermined load or pressure is exceeded within the combustion bowl.

First claim

What is claimed is:

1 . A piston for an internal combustion engine comprising:
a piston head, having a piston head rim adapted to engage with a cylinder head; a combustion bowl having a bowl base, the bowl base having a combustion surface facing the cylinder head and a bottom surface facing a connecting rod; and a failure initiation structure in the bottom surface of the bowl base configured so that a favorable fracture occurs along the failure initiation structure that separates a fragment of the bowl base from the combustion bowl when a predetermined load in the combustion bowl is exceeded.

2 . The piston of claim 1 wherein the failure initiation structure is a groove.

3 . The piston of claim 1 wherein the failure initiation structure is an interrupted groove.

4 . The piston of claim 1 wherein the failure initiation structure is ring-shaped.

5 . The piston of claim 1 wherein the failure initiation structure is configured so the fragment is retained on a head portion of the connecting rod.

6 . The piston of claim 4 wherein the failure initiation structure is located circumferentially around an elevated portion of the bowl base.

7 . An internal combustion engine comprising:
a piston configured to be disposed within a cylinder bore, said piston having a piston head, having a piston head rim adapted to engage with a cylinder head, a combustion bowl having a bowl base, the bowl base having a combustion surface facing the cylinder head and a bottom surface facing a connecting rod; and a failure initiation structure in the bottom surface of the bowl base configured so that a favorable fracture occurs along the failure initiation structure that separates a fragment of the bowl base from the combustion bowl when a predetermined load in the combustion bowl is exceeded.

8 . The internal combustion engine of claim 7 wherein the failure initiation structure is a groove.

9 . The internal combustion engine of claim 7 wherein the failure initiation structure is an interrupted groove.

10 . The internal combustion engine of claim 7 wherein the failure initiation structure is ring-shaped.

11 . The internal combustion engine of claim 7 wherein the failure initiation structure is configured so the fragment is retained on a head portion of the connecting rod.

12 . The internal combustion engine of claim 10 wherein the failure initiation structure is located circumferentially around an elevated portion of the bowl base.

13 . A method of producing a piston for an internal combustion engine comprising:
providing a piston head having a piston head rim adapted to engage with a cylinder head, providing a combustion bowl within the piston head having a bowl base, the bowl base having a bottom surface, and providing a failure initiation structure in the bottom surface of the bowl base configured so that a favorable fracture along the failure initiation structure separates a fragment of the bowl base from the combustion bowl when a predetermined load in the combustion bowl is exceeded.

14 . The method of claim 14 , wherein the step of providing a failure initiation structure comprises machining a groove in the bottom surface of the piston.

15 . The method of claim 14 , wherein the step of providing a failure initiation structure comprises forging a groove during formation of the piston.

Assignees

• Caterpillar Inc

Inventors

• Graham Curtis J
• Cavanaugh Daniel T
• Walker Waylon S

Classifications

• F02F3/26

  having combustion chamber in piston head (the surface thereof being covered F02F3/14) · CPC title

• F02F3/28 Primary

  Other pistons with specially-shaped head · CPC title

• F02B77/08

  Safety, indicating, or supervising devices (thermal insulation F02B77/11; monitoring or diagnostic devices for exhaust-gas treatment apparatus F01N11/00) · CPC title

• F02F3/20

  the means being a fluid flowing through or along piston · CPC title

• F02F2200/04

  Forging of engine parts · CPC title