Abstract: A ring saw includes a disc body having a circumferential edge with a first circumferential bearing groove. A cutting ring is mounted for rotation about the circumferential edge of the body. The cutting ring has an inner annular surface that carries both a circumferential gear profile and a second circumferential bearing groove. Ball bearings are positioned in side by side relation in a circumferential bearing race defined by the first circumferential bearing groove and the second circumferential bearing groove. A circumferential seal is provided between the body and the cutting ring, which is adapted to prevent abrasives from entering into the bearing race and interfering with ball bearings. At least one driving gear is carried by the body and engaged with the circumferential gear profile to impart rotational movement to the cutting ring.

Abstract: A ring saw includes a disc body having a circumferential edge with a first circumferential bearing groove. A cutting ring is mounted for rotation about the circumferential edge of the body. The cutting ring has an inner annular surface that carries both a circumferential gear profile and a second circumferential bearing groove. Ball bearings are positioned in side by side relation in a circumferential bearing race defined by the first circumferential bearing groove and the second circumferential bearing groove. A circumferential seal is provided between the body and the cutting ring, which is adapted to prevent abrasives from entering into the bearing race and interfering with ball bearings. At least one driving gear is carried by the body and engaged with the circumferential gear profile to impart rotational movement to the cutting ring.

Abstract: A portable sawmill with bidirectional cutting circular saws includes a saw support pivotally mounted to a primary support structure for pivotal movement about a pivot axis which is transverse to the direction of movement. Two circular saws are rotatably mounted one above the other on the saw support. A first one of the two circular saws rotates in a first rotational direction and a second one of the two circular saws rotates in a second rotational direction. The teeth on both of the two circular saws are always moving toward a log resting on the log support as the log is being cut. An actuator is provided for selectively pivoting the saw support to invert the positioning of the two circular saws so that the teeth on both of the two circular saws continue to move toward the log being cut upon a change in direction occurring.