Bear (tool)

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In toolmaking, the bear is the name of the hammer head for machine hammers , presses , rams and similar tools. The bear is the actual tool in the sense of the technical jargon, i.e. the assembly of the machine that processes the workpiece directly.

Originally referred to bear in the event of ram block ( ram ) or a tamping block. In the case of a drop forging hammer , it is the upper moving part with the tool holder. In the case of a counter-blow hammer , where both parts of the tool holder are movable, a distinction is made between upper and lower rams. The distinctions between press (pressing instead of hitting), ram (the workpiece is moved, not formed) and hammer are increasingly beginning to merge in numerous special shapes, and the shaping parts are becoming more and more complex (compare forging saddles ).

The bear of a drop hammer , e.g. B. belt drop hammer, board drop hammer, steam or air hammer , moves up and down in lateral guides and often has a significant weight. In the 19th century bears already weighed 400 kg. In modern hydraulic presses , the weights and dimensions reach larger values: The bear of a 1,000 t press from 2007 weighs 35 t. The entire press without tools and attachments weighs 264 t and is almost 8 m high.

Individual evidence

  1. bear, m.. In: Jacob Grimm , Wilhelm Grimm (Hrsg.): German dictionary . tape 1 : A - Beer whey - (I). S. Hirzel, Leipzig 1854 ( ). “A heavy block to drive in, to pile up the piles, ram blocks, ramming blocks, of uncertain origin, maybe from Beren , hit. because one can hardly think of the animal fable of the bear who sticks his head into the crack of a beam. bohem too. beran . "
  2. Willy Pockrandt, Joseph Vincent Woodworth: Forging in the die and production of the forging dies . 2nd Edition. Springer-Verlag, 2013, ISBN 978-3-662-33858-2 , pp. 86 ( limited preview in Google Book search).