ROCHE structural principle of a planetary gear unit, composed of the body parts, the output shaft, the output shaft seal, output bearing, sun cap, carrier, internally toothed ring, planetary gear stage gear, roller shaft, the sun gear, C-type buckle ring, the force bearing, input shaft seal, the force flange, O-rings, ventilation plugs, keys, washers, hex screws. Second, the transmission structure of planetary gear transmission principle is a combination of the highest current gear reducer efficiency, the basic transmission structure into four parts: 1, 2 sun gear, a planetary gear (combined in the planet carrier) 3, the internal gear ring 4, stage gear drive directly connected sources to start a sun gear, a combination of the sun gear in the planetary gear carrier of the planetary gear drive operation. The whole group of planetary gear system automatically runs along the outer ring gear to rotate the output shaft connected to the planet carrier output to accelerate purposes. Higher reduction ratio is multiplied by a plurality of sets required gear and the planetary gear stage cumulative from. Third, the deceleration characteristics 1, high torque, high impact: the planetary gear mechanism of the transmission mode just like in traditional parallel gears. Only rely on the traditional gear between two gears handful of point-contact surface squeezed drive, all loads concentrated in a small gear in contact with the surface, prone to friction between the gear and fracture. The planetary gear reducer having six larger area with the gear contact surface 360 ??uniform load, a plurality of gear face common even withstand an instant impact load, high torque make it better able to withstand the force of the impact, the body and each bearing parts are not because of the high load and damaged or broken. 2, small size, light gravity: the traditional gear reducer design Jie multiple sets of staggered drive size gear tend to slow down, due to the reduction ratio of the two gears shall be in multiples of the number of value generation, between the size of the pitch to have a certain gear more bite, So gear box housing space is great, especially the more need deceleration by two or more combinations of speed ratio gear box connection combinations, the relative weakening of the structural strength, more so gear box is lengthened, resulting in a very large size and weight. Structure of planetary gear unit needs to follow the number of segments repeated connections to complete a separate multi-segment portfolio, small size, light weight, the appearance of light, to make the design more valuable dwarf sense. 3, high efficiency, low backlash: Because each set of gear reducer drive gear only a single tooth surface occlusal contact, when the transmission torque is equal to stress the need for greater tooth surface, and therefore the gear must be greater mold design the greater the number and thickness, modulus gear will cause intermediate gear runout tolerance value increases, the formation of relatively high gear backlash, backlash paragraphs cumulative reduction ratio between increases. The unique combination of planetary gears multi uniform seal, arc enveloping structure of the external gear ring gear close connection between the outer ring and the planetary gear, the adhesion between high gear, in addition to enhancing the speed reducer efficiency than high Design itself can achieve high-precision positioning effect. Fourth, the installation method of family reducer, planetary gear its small size, high transmission efficiency, wide deceleration range, high precision and many little, but is widely used in servo, stepper, DC and other transmission system. Its role is in ensuring the precise transmission of the premise, which is primarily used to reduce the speed increases torque and reduces the load / motor inertia ratio. Proper installation, use and maintenance reducer, is to ensure that an important part of the normal operation of machinery and equipment. Therefore, when installing the planetary gear, be sure to strictly follow the installation related issues, carefully assemble and use. 1, before installation check the motor and reducer are intact, and strictly check the size of the motor and gear parts connected to match, here is the positioning of the motor boss, input shaft and the gear grooves and other dimensions and tolerances. 2, unscrew the screw gear flange on the outside of the dust hole, adjust PCS system clamping ring to make holes in the side of the hole with dust, tighten hexagonal insertion. After removal of the motor shaft key. 3, the motor and gearbox natural connection. Must ensure that when connecting the gear output shaft is consistent with the motor input shaft concentricity, and both parallel to the outer flange. As the heart of the inconsistency will cause the motor shaft gear reducer break or wear. Note: Do not hit with a hammer, etc., to prevent the axial force or radial force is too large to damage the bearings or gears. Be sure to tighten the mounting bolts screwed tightly after another force bolts. Before installation, the motor input shaft, positioning boss and reducer to connect parts of the anti-rust oil wipe clean with gasoline or zinc salt and water. Before connecting the motor and reducer should first motor shaft keyway and bolt tightening force vertical. In order to ensure uniform force, the first on any of the angular position of the mounting bolts screwed, but do not tighten, then screw on the two mounting bolts of the angular position of the last one by tightening the four mounting bolts. Finally, tightly screw bolt force. All the bolts are required clamping force with a torque wrench according to the indicated fixed torsion torque data fixed and checked. Installed correctly and the machine gear reducer similarities between the machine and the drive motor is properly installed between. The key is to make sure the gear output shaft consistent with the driving portion of the shaft concentricity. Fourth, the formulas and examples 1, HP = (HP horsepower, T torque, N, speed) 2, the planetary gear torque = 9550 × ÷ Motor power Motor power input speed ratio × × use efficiency (95%) 3, example : (1) a known number of revolutions of the output shaft 90rpm, the input shaft rotation number of 1800rpm, seeking the reduction ratio? R == 20 namely: reduction ratio = 20 (2) into the power transmission horsepower 1HP, reduction ratio of 20: 1, the design is 100% transmission efficiency, find the output torque? HP = have: T == 0.3979kg-m