METHOD FOR THE PRODUCTION OF A PISTON FOR AN INTERNAL COMBUSTION ENGINE AND PISTON FOR AN INTERNAL COMBUSTION ENGINE

• US 20130014724A1
• Filed: 09/06/2011
• Published: 01/17/2013
• Est. Priority Date: 07/12/2011
• Status: Active Grant

• Current Assignee: Mahle International GmbH (MAHLE-STIFTUNG GmbH)
• Original Assignee: Mahle International GmbH (MAHLE-STIFTUNG GmbH)
• Inventors: BISCHOFBERGER, Ulrich
• Granted Patent: US 8,459,228 B2
• Time in Patent Office: Days
• US Class Current: 123/193.6
• CPC Class Codes: B23K 2101/003 Pistons
• CPC Class Codes: B23K 26/18 using absorbing layers on the workpiece, e.g. for marking or protecting purposes
• CPC Class Codes: B23K 26/28 of curved planar seams
• CPC Class Codes: B23K 35/224 Anti-weld compositions; Braze stop-off compositions
• CPC Class Codes: B23K 35/3601 with inorganic compounds as principal constituents
• CPC Class Codes: B23K 35/3606 Borates or B-oxides
• CPC Class Codes: B23K 35/3607 Silica or silicates
• CPC Class Codes: B23P 15/10 pistons
• CPC Class Codes: F02F 2003/0061 by welding
• CPC Class Codes: F02F 3/003 the parts being connected by casting, brazing, welding or clamping
• CPC Class Codes: F02F 3/0084 the pistons being constructed from specific materials
• CPC Class Codes: Y10T 29/49254 Utilizing a high energy beam, e.g., laser, electron beam

Abstract

A method for the production of a piston for an internal combustion engine, composed of at least two components, each of which has at least one corresponding joining surface, has the following steps: a) pre-working the at least two components, at least in the region of the joining surfaces; b) coating at least a part of the surface of at least one component with a covering medium containing at least one phyllosilicate; c) assembling the at least two components; d) connecting the at least two components along their corresponding joining surfaces, by means of beam welding, to produce a piston blank; e) removing the covering medium and any excess weld material adhering to it; and f) machining the piston blank to produce a finished piston.

Claims

1. A method for the production of a piston for an internal combustion engine, composed of at least two components, each of said components having at least one corresponding joining surface, comprising the following method steps:

a) pre-working the at least two components, at least in a region of the joining surfaces;

b) coating at least a part of a surface of at least one of the components with a covering medium containing at least one phyllosilicate as well as disodium tetraborate;

c) assembling the at least two components together;

d) connecting the at least two components along their corresponding joining surfaces, by means of beam welding, to produce a piston blank;

e) removing the covering medium and any excess weld material adhering to the covering medium from the piston blank; and

f) machining the piston blank to produce a finished piston.

2. The method according to claim 1, wherein bentonite is used in step b).

3. The method according to claim 1, wherein the covering medium contains disodium tetraborate.

4. The method according to claim 1, wherein in step b), the covering medium is applied at least 1 mm removed from an edge of each joining surface.

5. The method according to claim 1, wherein in step b), the covering medium is applied in the form of a suspension.

6. The method according to claim 5, wherein an aqueous suspension is used.

7. The method according to claim 5, wherein after step b), the coated components are dried by being heated to 80°

C. to 180°

C.

8. The method according to claim 1, wherein in step b), the covering medium is thermally sprayed in the form of a powder.

9. The method according to claim 1, wherein in step b), the covering medium is applied in a layer thickness of at least 100 μ

m.

10. The method according to claim 1, wherein before step b), the components to be coated are preheated to 50°

C. to 80°

C.

11. The method according to claim 1, wherein in step e), the covering medium is removed by washing with warm or cold water.

12. A piston for an internal combustion engine produced by means of a method according to claim 1.