Mahle International Gmbh

Rolf Kirschner

Patrick Altherr

Markus Walch

Thorsten Ihne

Mario Mohler

Falk Schneider

Roland Schacherer

Oliver Fritz

The present disclosure concerns a slotted guide of a valve train of an internal combustion engine. The slotted guide includes two guide tracks, which cross one another in a crossing region, for guiding a switching pin of a cam follower of the valve train. The two guide tracks have an on-track region, a crossing region, and an off-track region. At least one radial projection, structured and arranged to protrude beyond the slotted guide in a radial direction, is provided in or downstream from the off-track region of at least one guide track.

Slotted guide

A valve train may include a camshaft, a cam sleeve adjustable in an axial direction between first and second positions and non-rotatably arranged on the camshaft, a first cam and at least one second cam, a pin and at least one cam follower mounted thereon, a guide contour arranged on the cam sleeve and having first and second guide tracks, and a control pin optionally engaging in the first or second guide track to adjust the cam sleeve between the first and second positions. The at least one cam follower in the first and second positions may interact respectively with the first and second cams. On the camshaft or an internal surface of the cam sleeve, first and second snap-in recesses and a third snap-in recess therebetween may be arranged. A snap-in device having a snap-in element preloaded into the snap-in recesses may be provided, the snap-in recess fixing the cam sleeve in the first or second position. The first and second guide tracks may intersect in an intersection region. Between the first and third snap-in recesses and between the second and third snap-in recesses, first and second snap-in humps may respectively be arranged. The snap-in element may engage in the third snap-in recess when the control pin is in the intersection region.

Valve train of an internal combustion engine

An adjustable camshaft of an internal combustion engine may include an outer shaft and an inner shaft arranged coaxially to the outer shaft and rotatable over a predefined angle. At least one first cam may be connected rotationally fixedly to the inner shaft. A second cam may be arranged beside the first cam and may be connected rotationally fixedly to the outer shaft. The first cam and the second cam may each be operatively associated with a common valve. Rotation of the first cam relative to the second cam may impart an extension of a valve opening time of the valve. The first cam and the second cam may each include an identical circular segment section in an elevated region of valve lift. The circular segment section of the first cam and the second cam may merge without interruptions during rotation about the predefined angle range.

Adjustable camshaft

The present invention relates to a method for grinding of cam profiles on a camshaft (), having an inner shaft () and an outer shaft () arranged coaxially one inside the other and mounted to rotate with respect to one another. The camshaft () additionally has first and second cams () that can rotate with respect to one another over a limited circumferential angle about the camshaft axis (), the first cams () of which are fixedly connected to the inner shaft () and the second cams () of which are fixedly connected to the outer shaft (). It is essential to this invention that during and/or after the grinding operation a fluid is forced under pressure into the outer shaft (), thereby preventing penetration of grinding dust into the interspace () between the first cams () and the outer shaft () or flushing out any grinding dust that has already penetrated.

Growing community of inventors

Esslingen, Germany

Rolf Kirschner