| 摘要 |
PROBLEM TO BE SOLVED: To achieve a reduction in diameter dimension of a reduction gear of a part provided with a brake mechanism, distortion prevention during heat treatment and machining of a ring gear, and an increase in heat treatment efficiency.SOLUTION: A driving device of construction machinery includes a brake mechanism 19 that comprises both brake discs 23 and 24 on rotation and fixing sides, a brake piston 21 and a brake spring 20. The rotation-side brake disc 23 is provided in the state of rotating integrally with a planetary shaft 25, on the upside of a planetary gear P1 of a first stage deceleration part 9. The whole brake mechanism 19 including the rotation-side brake disc 23 is arranged in the state of overlapping both gears P1 and R1, on the upside with respect to both the planetary and ring gears P1 and R1. |
