Multi-part piston for an internal combustion engine and method for its production

• US 20100108017A1
• Filed: 06/23/2009
• Published: 05/06/2010
• Est. Priority Date: 11/06/2008
• Status: Active Grant

• Current Assignee: Mahle International GmbH (MAHLE-STIFTUNG GmbH)
• Original Assignee: Mahle International GmbH (MAHLE-STIFTUNG GmbH)
• Inventors: Schnaiter, Frank, Bing, Karlheinz
• Granted Patent: US 8,161,935 B2
• Time in Patent Office: Days
• US Class Current: 123/193.600
• CPC Class Codes: B23K 13/02 Seam welding
• CPC Class Codes: B23K 2101/003 Pistons
• CPC Class Codes: B23P 15/10 pistons
• 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: Y10T 29/49252 Multi-element piston making

Abstract

A method for producing a multi-part piston for an internal combustion engine and the piston itself, which has an upper piston part and a lower piston part, each having an inner and an outer support element, which elements delimit an outer circumferential cooling channel and an inner cooling chamber. The inner support element of the upper piston part and/or the inner support element of the lower piston part have at least one recess on their surface. The upper piston part and the lower piston part are connected with one another by pressure welding.

Claims

1. A multi-part piston for an internal combustion engine, comprising:

an upper piston part having an inner support element and an outer support element; and

a lower piston part having an inner support element and an outer support element,

wherein said support elements delimit an outer circumferential cooling channel and an inner cooling chamber, wherein the inner support element of the upper piston part or the inner support element of the lower piston part have at least one recess on their surface, and wherein the upper piston part and the lower piston part are connected with one another by means of pressure welding.

2. The piston according to claim 1, wherein there are two or more of said recesses.

3. The piston according to claim 1, wherein both the inner support element of the upper piston part and the inner support element of the lower piston part have at least one recess on their surfaces, said at least one recess on the upper piston part and said at least one recess on the lower piston part being positioned to align with each other.

4. The piston according to claim 1, wherein at least one of the upper piston part and the lower piston part are forged parts.

5. The piston according to claim 1, wherein at least one of the upper piston part and the lower piston part are produced from a steel material.

6. The piston according to claim 1, wherein the upper piston part and the lower piston part are connected with one another by inductive resistance pressure welding.

7. A method for the production of a multi-part piston for an internal combustion engine, having an upper piston part and a lower piston part, wherein the upper piston part and the lower piston part each have an inner and an outer support element, which elements delimit an outer circumferential cooling channel and an inner cooling chamber, comprising the following method steps:

producing the upper piston part and the lower piston part;

introducing at least one recess into a surface of the inner support element of the upper piston part or the inner support element of the lower piston part; and

connecting the upper piston part and the lower piston part by pressure welding.

8. The method according to claim 7, wherein two or more recesses are introduced into the surface of the inner support element of the upper piston part or of the lower piston part.

9. The method according to claim 7, wherein at least one recess is introduced into the surface of the inner support element of the upper piston part, and at least one recess is introduced into the surface of the inner support element of the lower piston part, and wherein said recesses are positioned so that they are aligned with one another before pressure welding.

10. The method according to claim 7, wherein the recesses are introduced by forging or machining.

11. The method according to claim 7, wherein at least one of the upper piston part or the lower piston part are produced by means of forging.

12. The method according to claim 7, wherein at least one of the upper piston part and the lower piston part are produced from a steel material.

13. The method according to claim 7, wherein the upper piston part and the lower piston part are connected with one another by inductive resistance pressure welding.