Guillotine blade with doubly inclined rear face - forms primary and secondary grinding faces and secondary face has given degree of roughness

摘要

The guillotine blade (1) may be for use on paper cutting appliance and has a doubly inclined (A, B) whetting face. The face of greatest inclination (B) forms the cutting edge. It has a surface roughness of not more than 0.02 micron. The arrangement extends the intervals between blade resharpening operations. The face of least inclination (A) forms the primary whetting face. It has a roughness of not more than 0.9 micron, and is inclined at 19 to 20 deg. to the plane face (C). The increase in inclination of the secondary whetting face (B) relative to the primary face (A) is between 1 deg. and 5 deg. and the roughness of the plane face (C) may also be not more than 0.02 micron. The cutting edge may be formed by successive grindings ontaining the primary (1) and secondary (B) faces.