One piece piston with supporting piston skirt

• US 6,327,962 B1
• Filed: 08/16/1999
• Issued: 12/11/2001
• Est. Priority Date: 08/16/1999
• Status: Expired due to Fees

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Kruse, Brian K.
• Primary Examiner(s): Ryznic, John E.
• Application Number:
  US09/375,171
• Time in Patent Office: 848 Days
• Field of Search: 921/76, 921/81.R, 921/86, 922/09, 922/14, 922/38, 922/24, 922/31, 123/193.6
• US Class Current: 92/186
• CPC Class Codes: F02F 2003/0061 by welding
• CPC Class Codes: F02F 2200/04 Forging of engine parts
• CPC Class Codes: F02F 3/003 the parts being connected by casting, brazing, welding or clamping
• CPC Class Codes: F02F 3/22 the fluid being liquid
• CPC Class Codes: F05C 2201/0448 Steel

Abstract

A one piece piston for an internal combustion engine has a piston skirt that is connected to a flange portion and a supporting portion of a piston body. The piston skirt provides support to the flange portion and a piston ring belt portion disposed about and connected to the piston body. The one piece piston has a closed piston cooling gallery defined by the piston body, the flange portion and piston ring belt portion.

Claims

1. A one piece piston;

comprising;

a piston body having a top surface and a longitudinal axis;

a support portion extending in a direction longitudinally from said piston body;

a first pin boss and a second pin boss being connected to said support portion, said first and second pin bosses being spaced apart and each having a pin bore, each of said pin bores having a bore axis and being axially aligned with each other, said bore axes being oriented transverse to said longitudinal axis;

a flange portion connected to said piston body at a preselected location between the top surface and the pin bore, said flange portion extending substantially radially from said piston body;

a piston skirt having first and second skirt portions, said first and second skirt portions each being connected to said flange portion and said support portion, said piston skirt supporting the flange portion on the support portion, said first skirt portion being spaced from and opposite the second skirt portion, said first and second skirt portions extending from the flange portion in a substantially axial direction relative to the longitudinal axis;

said piston body, support portion, flange portion, and piston skirt being formed in one piece;

a ring belt portion disposed about said piston body, said ring belt portion being connected to said piston body and to said flange portion by welding, said piston ring belt portion having first and second ends and an inside surface, said inside surface being welded to the piston body and said second end being welded to the flange portion;

a piston cooling gallery disposed annularly in the piston body, said piston cooling gallery being closed by said flange and ring belt portions and defining a closed piston cooling gallery; and

said flange portion having a ring end portion, said ring end portion including a first side of a first piston ring groove of said plurality of piston ring grooves and said piston ring belt portion defining a second side of the first piston ring groove, said first and second sides being spaced a preselected distance apart, said welding connecting the flange portion to the piston ring belt portion at a location between the first and second sides of the first piston ring groove.

2. A one piece piston, comprising:

a piston body having a top surface and a longitudinal axis;

a support portion extending in a direction longitudinally from said piston body;

a first pin boss and a second pin boss being connected to said support portion, said first and second pin bosses being spaced apart and each having a pin bore, each of said pin bores having a bore axis and being axially aligned with each other, said bore axes being oriented transverse to said longitudinal axis;

a flange portion connected to said piston body at a preselected location between the top surface and the pin bore, said flange portion extending substantially radially from said piston body;

a piston skirt having first and second skirt portions, said first and second skirt portions each being connected to said flange portion and said support portion, said piston skirt supporting the flange portion on the support portion, said first skirt portion being spaced from and opposite the second skirt portion, said first and second skirt portions extending from the flange portion in a substantially axial direction relative to the longitudinal axis to a location past the pin bore, said first and second skirt portions each have first and second spaced end portions, said first and second skirt portions each extending between the first and second pin bosses and each being connected at the first end portion to the first pin boss and at the second end portion to the second pin boss;

said piston body, said support portion, said flange portion, and said piston skirt being forged in one piece from a steel material;

a ring belt portion disposed about said piston body, said ring belt portion being connected to said piston body and to said flange portion by welding, said piston ring belt portion having first and second ends and an inside surface, said inside surface being welded to the piston body and said second end being welded to the flange portion;

a piston cooling gallery disposed annularly in the piston body, said piston cooling gallery being closed by said flange and ring belt portions and defining a closed piston cooling gallery; and

said flange portion having a ring end portion, said ring end portion including a first side of a first piston ring groove of said plurality of piston ring grooves and said piston ring belt portion defining a second side of the first piston ring groove, said first and second sides being spaced a preselected distance apart, said welding connecting the flange portion to the piston ring belt portion at a location between the first and second sides of the first piston ring groove.

3. The one piece piston, as set forth in claim 2, wherein said first and second skirt portions each have an outer surface defined by a radius “

R”

generated about said longitudinal axis.

4. The one piece piston, as set forth in claim 2, wherein said closed piston cooling gallery having first and second spaced apart extreme end locations defining a preselected longitudinal gallery length “

L”

, said length “

L”

being of a magnitude sufficient to enable substantial shaking of a cooling fluid contained within the closed piston cooling gallery and cooling of the ring belt.

5. The one piece piston, as set forth in claim 2, wherein said piston ring belt portion having a plurality of spaced apart piston ring grooves disposed therein, said piston grooves being spaced axially relative to the longitudinal axis between the first and second extreme end locations of the closed piston cooling gallery.