Apparatus for testing abrasive grains in single-grit scratch tests

US4472961A · kind A · utility

Assignee

• Dynamit Nobel GmbH · DE

Inventors

• Gerhard Rehfeld · Aachen, DE
• Klaus-Jurgen Steffens · Rheinbach, DE

Key dates

• Filing date: Mar 19, 1982
• Grant date: Sep 25, 1984
• Expiry date: Mar 19, 2002

Classification

• Technology area (CPC G): Physics
• CPC primary: G01N2203/0623
• WIPO field: Measurement
• WIPO sector: Instruments

Abstract

An apparatus adapted to be mounted on a surface grinding machine is provided for testing abrasive grains in single-grit scratch tests. To permit specimen preparation and scratching to be carried out on a single machine without changeover and without reclamping the specimen, and to maintain the infeed in the scratching operation constant by giving the specimen a contour corresponding to the cross-feed error, a belt grinder and a scratching device comprising a support disk, mounted by means of a main flange and a counterflange, and a scratching disk mounted on the main flange and carrying a single grain secured to its periphery along with a force-measuring system disposed thereunder, are designed as a structural unit adapted to be mounted on the spindle of the surface grinding machine, with a belt tensioning arm mounted to the headstock. The requisite natural frequency of the force-measuring system is obtained by locating a grain holder, a piezoelectric quartz crystal and a necked-down titanium bolt with rapid-acting tightening means on the rotating scratching disk beneath the abrasive grain.