Abstract: A method of manufacturing a gear wheel with stub toothing for a change-speed gearbox includes drop-forging a gear wheel body and forming the stub toothing by cold die-grooving in the forging die using a forming tool with forming parts which are arranged in a fan-shaped manner. The forming ends penetrate into the tooth spaces, wherein the forming parts are guided jointly between an upper and a lower receiving plate and are moved in a direction radially inwards in such a way that material is displaced out of the region of the tooth flanks into the tooth root regions.

Abstract: Method for manufacturing a gear wheel with stub toothing for a change-speed gearbox, wherein, in a first forming step, a gear wheel body (1) is drop-forged and the stub toothing is formed finally in at least one further forming step by cold calibration in the forging die by means of a forming tool (23) with forming parts which are arranged in a fan-shaped manner and the forming ends of which penetrate into the tooth spaces, wherein the forming parts are guided jointly between an upper and a lower receiving plate (29, 30) and are moved in a direction radially inwards in such a way that material is displaced out of the region of the tooth flanks into the tooth root regions.

Abstract: In the treatment of articles with a sterilant gas such as an alkylene oxide, and the circulation of the gas throughout a treatment chamber containing the articles to be treated, a gas circulating system completely devoid of electrical contacts, switches, electrical motors and other potentially dangerous electrical components which could cause explosive ignition of the sterilant gas. The circulation system includes a fluid-driven turbine-like impeller completely isolated from the sterilant gas, and drivingly coupled to a fan blade which serves to force the gas through conduits and to circulate and recycle the sterilant gas throughout the treatment chamber. In a second embodiment of the invention a magnetically coupled drive is used to actuate the sterilant-circulating fan.