COMPONENT OPERATION / Swing Device SWING REDUCTION GEAR The swing reduction gear is a two-stage planetary gear type. Ring gear (8) is provided on inside of the housing, is fixed to the upperstructure with the bolt, and does not rotate. Shaft (6) in the swing motor drives first stage sun gear (5). Then, rotary power is transmitted to second stage sun gear (3) via first stage planetary gear (7) and first stage carrier (4). Second stage sun gear (3) rotates shaft (1) via second stage planetary gear (9) and second stage carrier (2). As shaft (1) meshes with the internal gear of swing bearing fixed to the undercarriage, the upperstructure is rotated.
T16J-03-02-002 1 - Shaft 4 - First Stage Carrier 6 - Shaft in Swing Motor 8 - Ring Gear 2 - Second Stage Carrier 5 - First Stage Sun Gear 7 - First Stage Planetary Gear 9 - Second Stage Planetary Gear 3 - Second Stage Sun Gear T3-2-2 5 4 3 2 1 6 7 8 9