A circular saw cutting machine comprising:
- a main spindle, a main spindle motor, and a power transmission mechanism, a frame movably guided on a guide rail between a cutting position and a withdrawal position under the transfer control of a transfer motor, and a cutter mount mechanism for mounting a circular saw on a mounting shaft provided at a top end of the main spindle in so that the circular saw integrally rotates with the main spindle without rotationally shifting relative to the main spindle;
- wherein the circular saw includes a mounting hole through which the mounting shaft can be inserted and a plurality of pin insertion holes equidistantly arranged in concentric positions around a center of the mounting hole,
- wherein the cutter mount mechanism comprises:
- a pull-in fixing mechanism including a cutter presser piece mounted to interpose the circular saw between the cutter presser piece and a front end face of the main spindle, a plurality of pins capable of being inserted through the pin insertion holes of the circular saw in concentric positions around a center of the mounting shaft of the main spindle, a plurality of pin holes into which the plurality of pins can be inserted, wherein each one pin, respectively, of the plurality of pins is provided on one of either a rear face of the cutter presser piece or the front end face of the main spindle and a corresponding pin hole to said one pin is provided on the other of the rear face of the cutter presser piece and the front end face of the main spindle to make pairs with the pins, wherein at least one of the plurality of pins is provided on the front end face of the main spindle, and wherein the cutter presser piece is pulled in toward the front end face of the main spindle to be fixed while the plurality of pins are inserted in the paired pin holes with the plurality of pins inserted through the plurality of pin insertion holes of the circular saw;
- and
- a pull-in release mechanism for releasing the fixing of the cutter presser piece by the pull-in fixing mechanism so that the cutter presser piece can be removed from the main spindle;
- and
- wherein the circular saw cutting machine further comprises a spindle home position stopping mechanism that includes a brake for stopping the rotation of the main spindle and a sensor for detecting a rotational angle of the main spindle, the main home position stopping mechanism stopping the main spindle in a predetermined home angle condition by controlling the main spindle motor and the brake based on the rotational angle detected by the sensor.