Multi-part cooled piston for an internal combustion engine

Abstract

Proposed is a multi-part cooled piston (1) for an internal combustion engine, which piston (1) is composed of an upper piston part (2) and a lower piston part (6). The upper piston part (2) forms an inner annular cooling duct (11) with the lower piston part (6), which cooling duct (11) is covered by an upper region (31) of the lower piston part (6). Said region (31) is of thin-walled design in such a way that it can be deformed in the manner of a plate spring.; Simple and fast assembly of the upper piston part (2) on the lower piston part (6), and a fixed and secure screw connection between the two piston parts, result in that the upper piston part (2) is provided on its underside with a blind bore (26) which is arranged centrally and coaxially with respect to the piston axis (25) and has an internal thread (28), and in that the upper region (31) of the lower piston part (6) has a threaded bolt (29) which is arranged centrally and coaxially with respect to the piston axis (25), points upward and has an external thread (30), with the internal thread (28) matching the external thread (30), such that the upper piston part (2) can be screwed to the lower piston part (6) by means of the blind bore (26) and the threaded bolt.

Description

technical field [0001] The invention relates to a multipart cooled internal combustion engine piston according to the preambles of the claims. Background technique [0002] A multipart cooled internal combustion engine piston is known from laid-open publication DE 102 57 022 A1, which consists of a piston upper part and a piston lower part. Bolts are provided on the underside of the upper piston part, and screw holes are provided in the upper region of the lower piston part, so that the two piston parts can be screwed together via the screws and the screw holes. In this case, the upper area of ​​the lower piston part is designed so thin-walled that it can be deformed like a disk spring when the upper piston part and the lower piston part are screwed together, so that a biasing force is exerted on the screw and the screw hole. , the biasing force stabilizes and secures the threaded connection formed here. However, it has the disadvantage that, when deformations occur in the...

AI Technical Summary

Problems solved by technology

However, it has the disadvantage that, when deformation occurs in the upper area of ​​the lower part of the piston, pressure-induced cracks can appear in the vicinity of the screw hole, causing loosening of the threaded connection and causing damage to the piston and thus to the engine in which it is installed

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