Abstract: A method for induction surface hardening includes, when in a feed mode, moving an induction coil of a hardening device over a ring surface of a work piece in a treatment direction, to heat the ring surface from an initial zone to a final zone. A sprayer, located downstream of the induction coil in the direction of treatment, is activated to apply quenching liquid to the heated ring surface to both cool and harden the ring surface. An unhardened soft zone is provided between the initial zone and the final zone. A supplementary induction coil, the induction coil and the sprinkler are respectively activated and deactivated separately at the start and end of the hardening, while the relative feed speed between the hardening device and the work piece, and/or the power supplied to each of the supplementary induction coil and the induction coil, are varied at the same time.

Abstract: The invention relates to a method for the progressive induction surface hardening of a closed curve trace of a workpiece, the closed curve trace and a hardening device being moved relative to one another in a feed mode to harden the closed curve trace starting from an initial zone to an end zone, an unhardened soft zone being provided. According to the invention, the workpiece is provided with a marking, the hardening device having a sensor for detecting said marking. The curve trace and the hardening device are moved relative to one another along the treatment direction until the senor detects the marking. Once the marking is detected, another movement takes place in the treatment direction before the hardening device is activated, the curve trace being hardened by the relative movement. The marking is again detected by means of the sensor and the hardening device is then deactivated. The invention also relates to an arrangement which is suitable for carrying out the method described.

Abstract: Methods for induction surface hardening of a ring surface of a work piece. The ring surface and a hardening device have an induction coil moved relative to one another in a treatment direction in a feed mode. A sprinkler located downstream of the induction coil in the direction of treatment serves to heat the ring surface, starting from an initial zone to a final zone, with the induction coil and then hardens it by cooling the ring surface with the sprinkler. An unhardened soft zone is provided between the initial zone and the end zone. The supplementary induction coil, the induction coil and the sprinkler are activated and deactivated separately at the start of hardening and at the end of hardening, respectively, the speed between the hardening device and the work piece and/or the power supplied to the supplementary induction coil and the induction coil varied at the same time.

Abstract: The invention relates to a method for the induction surface hardening of a ring surface of a workpiece, the ring surface and a hardening device having an induction coil being moved relative to one another in a treatment direction in a feed mode. A sprinkler is located downstream of the induction coil when seen in the direction of treatment and serves to heat the ring surface, starting from an initial zone to a final zone, by means of the induction coil and then to harden it by cooling the ring surface by means of the sprinkler, an unhardened soft zone being provided between the initial zone and the end zone.

Abstract: The invention relates to a method for the induction surface hardening of a ring surface of a workpiece, the ring surface and a hardening device having an induction coil being moved relative to one another in a treatment direction in a feed mode. A sprinkler is located downstream of the induction coil when seen in the direction of treatment and serves to heat the ring surface, starting from an initial zone to a final zone, by means of the induction coil and then to harden it by cooling the ring surface by means of the sprinkler, an unhardened soft zone being provided between the initial zone and the end zone.

Abstract: The present invention relates to a planar inductor for progressive case hardening, comprising a carrier and an induction coil, which is accommodated by the carrier and exposed on a first side of the carrier and which is in the form of a conductor loop. According to the invention, the inductor comprises two spacing elements, which are space apart from one another and inserted into the carrier and which protrude from the carrier and beyond the conductor loop on the first side. The invention further relates to a preferred method for producing the planar inductor.

Abstract: The invention relates to a method for the progressive induction surface hardening of a closed curve trace of a workpiece, the closed curve trace and a hardening device being moved relative to one another in a feed mode to harden the closed curve trace starting from an initial zone to an end zone, an unhardened soft zone being provided. According to the invention, the workpiece is provided with a marking, the hardening device having a sensor for detecting said marking. The curve trace and the hardening device are moved relative to one another along the treatment direction until the senor detects the marking. Once the marking is detected, another movement takes place in the treatment direction before the hardening device is activated, the curve trace being hardened by the relative movement. The marking is again detected by means of the sensor and the hardening device is then deactivated. The invention also relates to an arrangement which is suitable for carrying out the method described.