Abstract: Apparatus for grinding twist drills comprises a drive shaft and a grinding wheel, which is coupled to said shaft and is mounted thereon to be axially movable and tiltable relative to the shaft and is spring-loaded toward a drill-guiding structure facing the grinding surface of the grinding wheel. The drill-guiding structure comprises guiding passages for guiding drills differing in diameter against the grinding surface and in association with each grinding passage comprises at least one guide lug for extending into a flute of a twist drill extending through the associated guiding passage, and a drill stop for limiting the advance of the twist drill in the guiding passage against the elastically yielding grinding wheel.

Abstract: Apparatus for grinding twist drills comprises a drive shaft and a grinding wheel, which is coupled to said shaft and is mounted thereon to be axially movable relative to the shaft and is spring-loaded toward a drill-guiding structure facing the grinding surface of the grinding wheel. The drill-guiding structure comprises guiding passages for guiding drills differing in diameter against the grinding surface and in association with each guiding passage comprises at least one guide lug for extending into a flute of the twist drill extending through the associated guiding passage, and a drill stop for limiting the advance of the twist drill in the guiding passage against the elastically yielding grinding wheel. To said drill-guiding structure at least one abutment is connected which is engageable by the grinding wheel and has a higher hardness than the grinding wheel.

Abstract: 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.