| 摘要 |
The apparatus for grinding twist drills comprises a shaft and a grinding wheel which has a grinding surface and is rigidly secured to the shaft. The apparatus comprises also a drill-guiding body, which faces the grinding surface and is axially spaced from it and axially immovable relative to the grinding surface. The drill-guiding body is formed with a plurality of guiding passages for guiding twist drills differing in diameter toward the grinding surface. At least one guide lug is aligned with each guiding passage of the drill-guiding body and adapted to extend into a flute of a twist drill extending through the associated guiding passage. All guide lugs are mounted on a guide lug carrier, which is mounted to be axially movable between the drill-guiding body and the grinding surface and which is biased toward the grinding surface by a spring. At least one abutment consisting of a material which has a higher hardness than the grinding wheel is secured to the guide lug carrier and has an abutment surface which is parallel to and engageable by the grinding surface. This arrangement ensures that a constant distance from the guide lugs to the grinding surface will be maintained during the grinding operation in spite of the wear of the grinding wheel and the original shape of the grinding surface will be restored.
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