Saw chain sharpener for a chain saw

A saw chain sharpener for a chain saw having a saw chain disposed on a chain bar, wherein the saw chain has a plurality of cutting teeth, each cutting tooth having a cross section which defines a crook, the crook comprising an upstanding section and a projecting section, a portion of the upstanding section lies approximately parallel to a side surface of the chain bar, the projecting section is carried by the upstanding section, at least a portion of the projecting section lies in a plane perpendicular to the side surface of the chain bar, each projecting section having a top and a bottom surface, the bottom surface of the projecting portion being closer to the chain bar than the top surface, the top surface being joined to the bottom surface by a leading edge, the angle between the leading edge and the top surface being an acute angle, the saw chain sharpener comprising:

• a housing having left and right side walls defining a recess;
• a shaft having a top end and a bottom end, wherein said shaft is disposed inside of said recess and fastened at the top end to the housing;
• a sharpening tooth having a top and bottom surface, wherein said sharpening tooth is disposed on the bottom end of said shaft;
• and
• a mounting bracket having a recess for receiving the chain bar, wherein said mounting bracket comprises means for clamping said mounting bracket to said chain bar, and wherein said housing is removably attachable to an end of said mounting bracket so as to substantially center said recess of said housing over said saw chain;
• wherein said sharpening tooth is positioned at a cutting position so that said leading edge of each cutting tooth engages said top surface of said sharpening tooth as the sharpening tooth is relatively moved through a position within the crook of each cutting tooth, to sharpen the leading edges of the cutting teeth by running the chain saw and wherein said bottom surface of said sharpening tooth is located closer to said chain bar than said top surface of said sharpening tooth.

A chain saw comprising:

• a housing;
• a chain bar having a periphery attached to said housing;
• a motor disposed in said housing;
• a chain disposed on the periphery of said chain bar, wherein said chain comprises a plurality of cutting teeth, each cutting tooth having a cross section which defines a crook the crook comprising an upstanding section and a projecting section, a portion of the upstanding section lies approximately parallel to a side surface of the chain bar, the projecting section is carried by the upstanding section, at least a portion of the protecting section lies in a plane perpendicular to the side surface of the chain bar, each protecting section having a top and a bottom surface, the bottom surface of the projecting portion being closer to the chain bar than the top surface, the top surface is joined to the bottom surface by a leading edge, the angle between the leading edge and the top surface is an acute angle, and wherein said chain is movable around said periphery of said chain bar;
• a sharpener disposed on said chain bar positioned to sharpen said leading edge of each cutting tooth, wherein said leading edges of said cutting teeth are sharpened by said sharpener by relatively moving the sharpener through the crook of each cutting tooth while said chain is run around said chain bar powered by said motor.