SEAL STRUCTURE OF TURNING BEARING

To provide a seal structure of a turning bearing capable of restricting the seal degradation.SOLUTION: A seal structure of a turning bearing, comprises: a base substance; a revolving superstructure 4 that is located above the base substance and relatively rotational with respect to the base substance; a ring gear 21 provided in any one of the base substance and the revolving superstructure 4; a pinion 23 provided in the other of the base substance and the revolving superstructure 4 and meshing with the ring gear 21; lubricant for lubricating at least the engagement part of the ring gear 21 and the pinion 23; a bearing 25 that is located between the base substance and the revolving superstructure 4 and on the outside of the ring gear 21 and the pinion 23 in the radial direction; and a seal 27 for preventing debris from entry to the inside of the bearing 25, in which a ridge strip part 31 is provided between the ring gear 21, the pinion 23 and the seal 27, and projecting annularly upward from the base substance.SELECTED DRAWING: Figure 3 【課題】シールの劣化を抑制することができる旋回軸受のシール構造を提供する。【解決手段】基体と、基体の上方に位置させて、基体に対して相対回転自在な旋回体４と、基体と旋回体４の何れか一方に設けられたリングギヤ２１と、基体と旋回体４の何れか他方に設けられ、リングギヤ２１と噛合するピニオン２３と、リングギヤ２１とピニオン２３との少なくとも噛合部を潤滑する潤滑剤と、基体と旋回体４との間であって、リングギヤ２１及びピニオン２３よりも径方向外側に配置された軸受２５と、軸受２５の内部への異物の侵入を防ぐシール２７と、を備える旋回軸受のシール構造であって、リングギヤ２１及びピニオン２３と、シール２７と、の間に位置させて、基体から上方に向かって環状に突出する突条部３１が設けられている。【選択図】図３