SWING DEVICE OF CONSTRUCTION MACHINE

摘要

PROBLEM TO BE SOLVED: To reduce noise due to engagement of gears used a planetary gear deceleration mechanism of a swing device.SOLUTION: A planetary gear deceleration mechanism 47 of the highest stage connected to a motor shaft 24 is constituted of a helical sun gear 48, a plurality of helical planetary gears 51 engaged with the helical sun gear 48 and an internal gear 15D; and gear support carriers 52 each rotatably supporting each of the helical planetary gears 51. A vertical thrust load acting on the helical sun gear 48 is supported by a thrust load receiving member 56 for the sun gear, a vertical thrust load acting on the helical planetary gear 51 is supported by a thrust load receiving member 59 for the planetary gear, and a vertical thrust load acting on the helical planetary gear support carrier 52 is supported by a thrust load receiving member 62 for the carrier.