Device for the inductive heating of the inside of cylinder liners of reciprocating-piston engines for the purpose of hardening

US5134264A · kind A · utility

Assignee

• Mercedes-Benz Group AG · DE

Inventors

• Dieter Burger · Leinfelden, DE
• Walter Burbock · Stuttgart, DE
• Peter Linden · Beimerstetten, DE

Key dates

• Filing date: Apr 25, 1991
• Grant date: Jul 28, 1992
• Expiry date: Apr 25, 2011

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y02P10/25
• WIPO field: Materials, metallurgy
• WIPO sector: Chemistry

Abstract

A device for induction heating of the inside of cylinder liners of reciprocating-piston engines to a transformation temperature, for the purpose of hardening. An inductor head is equipper with an aligning device designed as a spreadable cage which is equipped on the outside with clamping bars, clamping bosses a clamping shells which can be applied free from play and under the effect of force against the inner surface of the cylinder liner. The inductor loop is also displaced radially and brought into the working position by means of these clamping shells. Heating and hardening is carried out only with the inductor head in the clamped and exactly aligned state, whereas, after the clamping shells and the inductor loops have been released, a further indexed movement of the inductor head is possible. The work is carried out at relatively high alternating-current frequencies in the range between 400 and 500 kHz and at relatively high energy densities in the range above 5 kw/cm.sup.2 .