GB642953A - Apparatus for and method of grinding - Google Patents

Abstract

642,953. Grinding strip metal. HAMILTON, A. E. Aug. 8, 1947, No. 22066. Convention date, Feb. 11, 1946. [Class 60] Apparatus for grinding strip metal comprises a power-driven coiling device for advancing and coiling the strip metal, a grinding roll positioned to engage the strip in a direction generally crosswise thereof, but the roll beng disposed on an axis that is diagonal to the path of travel of the strip, and means for rotating the roll in a direction to frictionally oppose pull on the strip by the coiling device. A roll stand 5 carries surfacing rolls 6, 7 which may be of abrasive material or be covered with helically wound abrasive strip. The roll 7 is belt-driven from a motor 9 carried by a bracket 4 secured to the roll stand; the roll 6 is belt-driven from another motor also carried by the roll stand. The roll stand is supported on an anti-friction bearing 12 and can be angularly adjusted by worm gear 13 and worm 14 operated by a handcrank 16. The strip 18 is drawn from a coil 19 and recoiled at 20 by counterclockwise rotation of a motor 22; the rolls 6, 7 are rotated clockwise and counterclockwise respectively, so that the strip between the coil 20 and rolls 6, 7 is in tension; the motor 21 may be completely de-energized, or may be caused to act as an brake so as to tension the strip between the rolls 6, 7 and coil 19. To reverse the travel of the strip the motor 21 is rotated clockwise, the motor 22 being completely de-energized or caused to act as a brake, and the direction of rotation of the rolls 6, 7 is reversed; the angularity of the roll stand is also reversed. Idler guide rolls 23, 24 direct the strip to guide tables 25, 26 having upturned edges to prevent lateral displacement of the strip due to the diagonal pull of the surfacing rolls, if the tensioning of the strip in insufficient to prevent this. When it is desired to grind only one surface of a strip, two strips back to back are fed through the apparatus. The strip may be first ground by rolls having grit of a certain grain size, and subsequently by rolls having grit of a smaller grain size; the strip may be traversed at a rate of 25-100 feet per minute and the rolls have a peripheral speed of 3,000-5,000 feet per minute.