Patent ID: 7431637

Claim:
A saw chain sharpener comprising: a sharpener body with an electric motor; a round shaft-shaped grinding tool attached to an end of the electric motor: a support member projected forward from the sharpener body: a projecting portion provided on a front end portion of the support member or on an attachment plate attached to the front end portion of the support member; and a holding plate attached forward of the saw chain sharpener and having a shape to be able to straddle and support an upper part of a saw chain, the holding plate having a vertical plate face having a long left-to-right length extending in a direction along the saw chain, an upper plate face placed on the upper part of the saw chain, and opposing vertical plate surfaces formed at leftward and rightward locations of the upper plate face; wherein the holding plate is supported on the front end portion of the support member or on the attachment plate so as to be horizontally rotatable in a certain range for orientation to align with a sharpening angle of a cutter blade positioned left or right of the saw chain to grind the cutter blade; the saw chain is clamped at both ends by a lower part face of the vertical plate face and the opposing vertical plate surfaces; the upper plate surface of the holding plate has an opening formed at a center thereof so as to make it possible to watch the grinding tool and the cutter blade from above; and the projecting portion having a thin width shape is aligned in height with the upper plate face of the holding plate, in which the projection portion fixes a cutting edge of the cutter blade to define an accurate cutting edge angle and presses an upper blade of the cutter blade from above to prevent the upper blade from wobbling caused by grinding.