| 摘要 |
PURPOSE:To obtain a flywheel free from generation of hardening strain and quenching crack by hardening the tooth part of a cast iron ring gear part disposed on the outside circumference in a flywheel body part by a laser, etc. then subjecting said part to high-temp. tempering treatment. CONSTITUTION:While a mirror 6 is in the position (a), a laser beam hardens the right face shown in the figure of the tooth face in a ring gear tooth part 5a through routes A, B. When the mirror 6 is moved to the position (b), the laser beam is reflected by the mirror 6 and is passed through routes A, C to harden the left side shown in the figure of the tooth part 5b. The ring gear 5 is then rotated right or left by as much as one tooth and the above-described operation is repeated. The above-mentioned operation is repeated for the tooth parts over the entire circumference of the ring gear part by which the tooth faces in the tooth parts over the entire circumference of the ring gear part are hardened. The integral cast iron ring gear 5 is thereafter subjected to a high-temp. tempering treatment. The cast ion ring gear is used after low-temp. tempering treatment. |
