Machining process for trapezoid rings with small axial dimensions, used in pistons of internal combustion engines
AssigneeKS Kolbenschmidt GmbH
InventorsReiner Friede, Denis Beller
Life of this patent
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Abstract
A method for producing a piston for internal combustion engines, where the piston includes a circumferential trapezoid annular groove for receiving trapezoid rings with small axial dimensions the groove having a groove base with adjoining surfaces and groove flanks. The groove base with adjoining surfaces is created in a first method step by machining using a cutting steel tool and the groove flanks are created in a further method step. Also disclosed are a piston produced according to the method and a cutting steel tool.
Claims3
A method for producing a piston for internal combustion engines comprising:
- machining in a first step a trapezoidal circumferential annular ring groove in a piston blank operable to receive trapezoidal-shaped rings, the first machining step further comprising:
- plunge cutting a groove base with a tool steel, the groove base having ends defining a height h4 greater than zero (0) millimeters and less than one (1) millimeter (mm);
- plunge cutting two flanks in the piston blank with the tool steel, each flank connected to a respective one of the base ends and extending radially and horizontally outward from a piston stroke axis, the two flanks oriented parallel to one another;
- plunge cutting two groove flanks in the piston blank with the tool steel, each groove flank connected to a respective one of the flanks and extending radially and angularly outward from the piston stroke axis;
- and
- machining in a second step the trapezoidal ring groove in the piston blank, the second machining step comprising finish machining the two groove flanks.
A method for producing a piston for internal combustion engines comprising:
- machining in a first step a trapezoidal circumferential annular ring groove in a piston blank operable to receive trapezoidal-shaped rings, the first machining step further comprising:
- plunge cutting a groove base having ends defining a height h4 greater than zero (0) millimeters and less than one (1) millimeter (mm);
- plunge cutting a radius R2 of 0.2 millimeters (mm) at each groove base end;
- plunge cutting two flanks in the piston blank, each flank connected to a respective one of the base ends and extending radially and horizontally outward from a piston stroke axis, the two flanks oriented parallel to one another;
- plunge cutting two groove flanks at an angle alpha (α) of 15 degrees and 12 minutes relative to one another in the piston blank, each groove flank connected to a respective one of the flanks and extending radially and angularly outward from the piston stroke axis;
- and
- machining in a second step the trapezoidal ring groove in the piston blank, the second machining step comprising finish machining the two groove flanks.
Dependencies are inferred from the claim text.