Mahle International Gmbh

Mahle Gmbh

Gottfried Schnaitmann

Ralf Braig

Rainer Fischer

Harald Boekle

Helmut Mueller

Achim Fedyna

Helmut MÜLLER

Harald BÖKLE

A tool spindle for a drilling tool may include a drive shaft for driving the drilling tool, a chuck connected rigidly to the drive shaft along a rotation axis directed longitudinally with respect to the drive shaft for receiving a clamping shank of the drilling tool, and at least one radial bearing radially enclosing at least a portion of the drive shaft for radially mounting the drive shaft, configured such that the radial bearing may mount the drive shaft to be rotatable about the rotation axis. The radial bearing may be an active magnetic bearing and may be configured such that it mounts the drive shaft to be pivotable about at least one pivot axis extending perpendicularly to the rotation axis through a fixed point, wherein the fixed point may be located in a centering countersink of the drilling tool when the drilling tool is clamped in the tool spindle.

Tool spindle having an active magnetic bearing

Pin bosses of a piston for an internal combustion engine each have a pin bore for supporting a piston pin. In order to reduce the tangential stresses in the zenith area of the pin bores, and thus to extend the service life of the piston, the inner areas of the pin bores as viewed in the direction of the bore axis have areas on both sides of the zenith that have a greater distance from the bore axis than the zenith of the pin bore, and the outer areas of the pin bores, as viewed in the direction of the bore axis, are transversely oval relative to the piston axis.

Pin bosses of a piston for an internal combustion engine

The invention relates to a piston (), which is comprised of an approximately circular cylindrical upper area () and of a lower area (), having two hubs (), which are set back toward the piston central axis () so that, in the upper area (), recesses () can be made, which are open toward the lower area (), in the vicinity of the hubs (). In order to make relief cuts () in the area between the hubs () and the upper area (), a salt mold part () is placed on the respective window insert (). The salt mold part () serves to produce the recesses () as well as the relief cuts () when casting the piston () and is washed out after the piston () has been cast.

Piston for a combustion engine and casting method for the production thereof

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Backnang, Germany

Gottfried Schnaitmann