Daimler Chrysler Ag

Martin Kruessmann

Henning Bloecker

Klaus Brandes

Jochen Paus

A process and system for manufacturing a built-up camshaft by which the operational safety of the camshaft is ensured in a simple manner in any engine operation and the camshaft can arbitrarily be adapted to abutments which have different positions because of the individual engine construction. At least one cam is pushed onto a hollow shaft, after which the hollow shaft is expanded between the two faces of the cam which extend transversely with respect to the longitudinal course of the hollow shaft and at the respective bearing point by means of a highly pressurized pressure fluid. This fluid is delivered by a lance-shaped probe introduced into the hollow space of the shaft. On the one hand, a press fit occurs between the cam and the hollow shaft and, on the other hand, a bulging of the bearing point of the hollow shaft occurs which bridges the distance between the hollow shaft and the abutment. The hollow shaft is sealed off between the expanded points by a sealing arrangement on the probe with respect to the expanding internal high pressure.

System for manufacturing built-up camshafts

A device and method for joining fitting parts provided with a passage opening on hollow profiles through partial expansion of the hollow profiles at the location of the fitting parts is provided. The fitting parts are slid on with the passage openings and are held in position by means of fluid high internal pressure expansion of the hollow profile. The device includes an expanding lance, which can be slid into the hollow profile and exhibits an axial borehole for the purpose of guiding the pressure fluid. The axial borehole is connected to a fluid high pressure generating system and exhibits a cross channel with an outlet for the pressure fluid in the direction of the hollow profile location to be expanded. The shell surface of the expanding lance exhibits sealing elements that are spaced apart and that define the outlet so as to seal axially on both sides against high pressure. To a reliable joining of the fitting parts on hollow profiles even when the hollow profiles exhibit small outer diameters, it is proposed that the expanding lance comprises two separate, aligned oblong components, of which at least one bears the axial borehole which empties freely on an end face near the outlet. The facing ends of the lance components form the cross channel for the axial borehole of the expanding lance. Furthermore, the device includes a drive unit operable to drive the two lance components into respective hollow profile ends, and are supported on an end side during the expansion phase.

Device and process for joining fitting parts on hollow profiles by means of fluid high internal pressure

A device and method for joining fitting parts provided with a passage opening on hollow profiles through partial expansion of the hollow profiles at the location of the fitting parts is provided. The fitting parts are slid on with the passage openings and are held in position by-means of fluid high internal pressure expansion of the hollow profile. The device includes an expanding lance, which can be slid into the hollow profile and exhibits an axial borehole for the purpose of guiding the pressure fluid. The axial borehole is connected to a fluid high pressure generating system and exhibits a cross channel with an outlet for the pressure fluid in the direction of the hollow profile location to be expanded. The shell surface of the expanding lance exhibits sealing elements that are spaced apart and that define the outlet so as to seal axially on both sides against high pressure. To a reliable joining of the fitting parts on hollow profiles even when the hollow profiles exhibit small outer diameters, it is proposed that the expanding lance comprises two separate, aligned oblong components, of which at least one bears the axial borehole which empties freely on an end face near the outlet. The facing ends of the lance components form the cross channel for the axial borehole of the expanding lance. Furthermore, the device includes a drive unit operable to drive the two lance components into respective hollow profile ends, and are supported on an end side during the expansion phase.

A process for manufacturing a built-up camshaft by which the operational safety of the camshaft is ensured in a simple manner in any engine operation and the camshaft can arbitrarily be adapted to abutments which have different positions because of the individual engine construction. At least one cam is pushed onto a hollow shaft, after which the hollow shaft is expanded between the two faces of the cam which extend transversely with respect to the longitudinal course of the hollow shaft and at the respective bearing point by means of a highly pressurized pressure fluid. This fluid is delivered by a lance-shaped probe introduced into the hollow space of the shaft. On the one hand, a press fit occurs between the cam and the hollow shaft and, on the other hand, a bulging of the bearing point of the hollow shaft occurs which bridges the distance between the hollow shaft and the abutment. The hollow shaft is sealed off between the expanded points by a sealing arrangement on the probe with respect to the expanding internal high pressure.

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Hamburg, Germany

Martin Kruessmann