Abstract: A device for dressing a tool having a plurality of teeth, wherein said device comprises a support surface having guiding elements, said guiding elements having at least two movable positioning elements, said movable positioning elements being adapted to be locked in a fixed position within said guiding elements such that said positioning elements form a stop for said tool; and a dressing tool mounted in a holding device positioned in front of a dressing side of said support surface, wherein said dressing tool is locked in position by a locking element during the dressing of said teeth, hence said dressing tool not being movable at least in a direction running substantially parallel to said dressing side; wherein said positioning elements are arranged in said guiding elements in said support surface such that said tool to be dressed engages with said positioning elements at its side turned towards said dressing side of said support surface, so that said tool can be moved towards said positioning elements by a

Abstract: A grinding attachment is provided for a hand-held power-operable rotary tool, which may consist of a hand-held drilling machine or a hand-held angular surface grinder. The grinding attachment comprises a drive pulley, a reversing pulley, an endless grinding belt trained around said pulleys, and a belt-tensioning finger extending between said pulleys. The reversing pulley has a slightly sloping peripheral surface and is rotatably mounted in a U-shaped bracket, which is axially extensible by means of a spring-biased push rod and in its peripheral surface is provided with a centrally disposed annular groove, which prevents a slipping of the grinding belt trained around the reversing pulley.

Abstract: This invention relates to an abrasive tool for grinding and polishing. A disk, which may consist of an abrasive disk or may carry a buffing pad consisting of an abrasive-containing woven fabric, is connected to a shaft that is adapted to be gripped by a driving chuck of a hand-held drilling machine or a hobbyist's machine. The shaft comprises a flexible shaft section and the tool is provided with means for reliably stiffening the shaft even during an operation at high speed and under stong abrasive forces. Besides, the tool should be usable as a grinding tool having a smaller grinding surface. An end flange is screwed to a first rigid shaft section and is disposed on the front face of the disk. A bowl which has a smaller radius than the disk is disposed on the rear of the disk.

Abstract: This invention relates to a fixture for holding twist drills having cutting edges to be ground. A stand is mounted on a base plate, which is displaceable and/or rotatable. The stand carries a bracket, which carries gripping unit for gripping the drill to be ground. The gripping unit comprises two gripping jaws and is adapted to be detachably mounted on the bracket in two predetermined positions. The bracket is formed with angle-section track grooves for guiding the gripping unit. Each gripping jaw comprises two outer edges, which extend along said track grooves, and adjacent to said outer edges is formed with two angle-section guides, which are adapted to interengage with said track grooves and to be slidably guided by said track grooves. The bracket is provided with a thrust screw for clamping the angle-section guides in the track grooves. A grinding apparatus is also disclosed, which comprises a grinding unit carrying a grinding wheel and in which the base plate is movable relative to the grinding unit.

Abstract: This invention relates to a fixture for holding a hole-cutting tool having cutting edges to be ground by means of a grinding wheel. The fixture comprising a stand carrying a pin and also comprises a gripping unit comprising two interconnected gripping jaws and detachably mounted on said pin in one predetermined position and adapted to be mounted thereon in at least one additional predetermined position, which jaws are adapted to grip said tool along an intermediate portion of its length. It is an object of the invention to provide such a tool-holding fixture which can be used in the crafts and in industry to grind relatively large twist drills or other hole-cutting tools which are 20, 40, 60 mm or even larger in diameter.

Abstract: In an abrasive tool for grinding or polishing, a grippable shaft is connected to an abrasive disc by means of a cylindrical elastic pad of plastic or rubber. A surrounding cap, preferably a screw cap, is provided, which for stiffening the assembly is adapted to be secured at one end to the abrasive disc and is engageable at its other end by means of an annular shoulder to an annular shoulder of the grippable shaft. Alternatively, the grippable shaft may extend through a cylindrical elastic ring of plastic or rubber, which ring is surrounded to a metal sleeve, which is connected to the abrasive disc and adapted to be tightened by a nut so as to stiffen the tool.

Abstract: This invention relates to a fixing device for fixing drills which are to be ground at their cutting edges. The fixing device comprises a baseplate, a stand carried by said baseplate, a pivot pin mounted on said stand near its top end, and a gripping device, which is slidably fitted on said pivot pin and adapted to grip the drill which is to be ground. The invention provides a simple and inexpensive fixing device of this type, which can be used for grinding twist drills or other drills, particularly by hobbyists, with adequate accuracy.

Abstract: The buffing wheel comprises a wheel body, abrasive-containing flexible material secured to the wheel body, and a drive shaft non-rotatably connected to the wheel body. The drive shaft comprises a flexible portion. A rigid member is carried by said drive shaft and slidable relative thereto between an inoperative position, in which said drive shaft is flexible, and a stiffening position, in which said rigid member stiffens said drive shaft.

Abstract: A carriage is slidably mounted on a baseplate and longitudinally guided thereon in a predetermined direction. An angle bracket is slidably and pivotally mounted on and adapted to be fixed to said carriage and is guided thereon transversely to said predetermined direction. A crosspin is mounted on said angle bracket and adapted to extend transversely to said predetermined direction. A drill holder for holding a twist drill is fitted on said crosspin to be pivotally movable thereon and extends laterally of said angle bracket at an angle to said predetermined direction.

Abstract: In a grinding head for carrying replaceably an abrasive sheet and for detachable and driving connection to a portable rotary power unit, the abrasive sheet is applied to the outer face of a circular dished support member having an outer convex face and an inner concave face, from which latter a screw-threaded shank projects, and overlapping marginal edge portions of the sheet are clamped between the support member and a correspondingly shaped clamping member on the shank, the clamping member being of smaller diameter than the support member, and having its concave face facing the concave face of the support member.