... taper cylindrical gear reducer, 4, DCYK for three-level hard-toothed surface taper cylindrical gears hollow shaft type ... the comprehensive efficiency per level to 0.98 gear, vibration and noise significantly reduced. (4) adopts many series, reduce speed, can ... convenient. (6) the series three level 4 combination model gear reducer (i. e. Level 3 assembly form, four level of transmission ratio) to ...