The structure of the Sumitomo excavator reducer is shown in Figure 3-60.
Reducer is a combination of two-stage simple planetary gear reducer. Its components are drive gear, sun gear, retainer, and hydraulic oil flowing into the piston motor. The shaft of the piston motor rotates at high speed, and the power is input to the reducer. The reducer part will reduce this high-speed rotation in two steps through a simple planetary two-stage reduction device, and rotate through the valve body with a ring gear to obtain low-speed, high-torque output power
(1) Operation of the 1st stage deceleration unit
The first-stage reduction unit consists of drive gear, planetary gear A, ring gear, retainer, needle roller bearing, and inner ring.
Planetary gear A and drive gear mesh together. The drive gear rotates clockwise, and the planetary gear A rotates counterclockwise. On the other hand, the planetary gear also meshes with the ring gear. The planetary gear kicks the teeth of the ring gear and revolves clockwise around the drive gear.
Because the planetary gears are fixed on the holder, free rotation through the needle bearing, the rotation is transmitted to the holder
up, the holder starts to rotate clockwise.
In addition, the retainer is combined with a spline and two-stage sun gear, and the rotation of the retainer is transmitted to the sun gear.
(2) Operation of the 2nd stage deceleration unit
The second-stage reduction unit consists of sun gear, planetary gear B, ring gear, retainer, needle bearing, and inner ring. Planetary gear B and sun gear mesh together. The sun gear rotates clockwise. The planetary gear B rotates counterclockwise.
Planetary gear B is fixed on the holder, and freely rotates through needle roller bearings. Moreover, the fixing device is combined with bolts and methods, and the flange is fixed on the body frame, so it cannot be rotated.
This planetary gear B cannot rotate in the same way as the first-stage reduction unit, and rotates counterclockwise in the installation position.In addition, the planetary gear B and the ring gear mesh together, and the counterclockwise rotation of the planetary gear B is transmitted to the ring gear. Up to rotate the ring gear counterclockwise.
Through the above action, the casing (the ring gear cuts into its inner diameter) receives the force from the planetary gear, and the casing rotates to transmit the power to the mechanical driven part connected to the casing.
