Sharpener for circular saw blade - rotates blade tooth in pitch steps as grinder cradle rocks axis leads grinder for blade cutting

摘要

The sharpener (5), has motor (10) driven grinding disc (11) on a rocking cradle (9,24). A handle rotates the blade in tooth pitch increments. An axially reciprocating (f) push rod (19) effects the incremental rotation, co-ordinated with reciprocal displacements of the disc (11) for penetration and withdrawal from successive inter tooth notches (34). The disc edge follows a curved trajectory due to the siting of the cradle fulcrum (8), obtg. a concave curve on active tooth edges. A trestle frame (1) supports a column screw (2) on which a slide (3) incorporating a temporary blade (30) support axle is mounted, also locating alternative holes (6,7) for the cradle fulcrum pin (8). The pin is offset from the disc (11) in the direction of operational blade rotation (F), and cams (15,20) rotated by crank handle may displace levers (17,21) to effect push rod (19) and cradle (9,24) movements.