Patent ID: 7909681

Claim:
A chainsaw sharpener for a saw chain with a round shaft-shaped grinding tool ( 7 ) which is attached to an end of a drive shaft of an electric motor ( 3 ), and which receives rotation force of the electric motor ( 3 ) so as to rotate, wherein a guide body ( 8 ) is securely fastened on and forward of the electric motor ( 3 ) of a sharpener body ( 2 ) via a mounting plate portion 88 a , 88 b so that the electric motor ( 3 ) and the guide body ( 8 ) are integrally assembled; where said guide body having, formed therein, an upper plate face ( 80 ), comprising four branch faces 80 a , 80 b , 80 c and 80 d that are wider than a saw chain and which have a substantial X-shape as seen in plan view, extending in two directions, and which are fit into and along an upper part of the saw chain ( 30 ) in alignment with a sharpening angle of either a left or right cutter blade ( 31 ) of the saw chain ( 30 ); ribs 83 a and 83 b that are bent downward and are formed at positions along a right side edge and a left side edge respectfully of branch faces 80 a , 80 d and 80 b , 80 c ; and wall pressure plate faces ( 81 a , 81 c , 81 d , 81 b ) that are directed downward and that are formed on a front end faces of said ribs 83 a and 83 b and on back end edges of the left and right branch faces 80 d , 80 c and serve as wall faces for pressing against a guide bar of the chainsaw such that manually pushing said electric motor toward said guide bar ( 40 ) of the chainsaw causes either wall pressure plate faces ( 81 a , 81 c ) or ( 81 b , 81 d ) to press against said guide bar ( 40 ) thereby accurately aligning said grinding tool with the sharpening angle and preventing wobbling; wherein formed at a substantially central surface of the guide body ( 8 ) is an exposure portion made of an opening or a curved portion or both of these which make it possible to watch, from above, the grinding tool ( 7 ) and at least a cutting edge ( 31 b , 32 b ) of a cutter blade ( 31 , 32 ) to be sharpened, and wherein provided on inside or side of the exposure portion is a guide portion ( 87 ), which is a narrow portion of the upper plate face ( 80 ) extending in a front-to-back direction, so that when said guide portion ( 87 ) is pressed from above said guide portion ( 87 ) contacts and secures an upper blade ( 31 a ) of said cutter blade ( 31 ) to prevent wobbling or tilting, and to further to define an accurate cutting edge angle.