Sharpener for cutting tools

A sharpening apparatus comprising:

• an endless abrasive belt configured for rotational advancement along a belt path;
• a roller which supports the belt as the belt rotationally advances along the belt path;
• and
• a tool guide surface adjacent a planar extent of the belt path adjacent the roller;
• and
• a tensioner assembly which applies a biasing force to the roller to maintain a selected tension in the belt and to facilitate translational displacement of the roller during deflection of the belt induced by presentation of a side of a cutting tool against the tool guide surface and a cutting edge of the tool against the belt, wherein the tensioner assembly comprises:
• a base member;
• a shaft comprising an outer surface with an elongated groove extending therein, the shaft rotatable about a central axis which extends in a first direction along an axial length of the shaft, the shaft having a proximal end supported by the base member and a distal end configured to support the roller;
• a biasing member disposed between the shaft and the base member to apply said biasing force to the roller;
• and
• a guide member supported by the base member and partially extending into the elongated groove, wherein advancement of the guide member in a second direction normal to the first direction induces axial rotation of the shaft about the central axis to adjust a tracking alignment of the belt on the roller.

A sharpening apparatus comprising:

• an endless abrasive belt;
• a roller adapted to contactingly engage the belt during continuous rotation of the belt about the roller in a selected rotational direction;
• and
• a tensioner assembly adapted to maintain a selected tension in the belt during said rotation thereof as a cutting edge of a tool contactingly engages the belt, the tensioner assembly comprising:
• a base member;
• a shaft moveable with respect to the base member and having a cylindrical outer surface into which extends an elongated groove, the shaft having opposing proximal and distal ends, the distal end supporting the roller;
• a biasing member disposed between the shaft and the base member to apply a biasing force to the roller in opposition to said tension in the belt;
• and
• a guide member secured in a stationary position with respect to the base member, the guide member comprising a nut threaded onto a threaded fastener connected to the base member, the nut partially extending into the groove, wherein rotation of the threaded fastener induces rotation of the shaft with respect to the base member.