Planetary gear motor is a piece of decelerating transmission equipment that is widely used whose efficiency is higher than that of the general ones. During the operation of the planetary gear motor, it is necessary to maintain it to improve the working efficiency. Factors affecting the efficiency of planetary gear motor in daily operation still need to be understood. Now, we have summarized some of the factors as follows.
1. During the operation of the precision planetary gear motor, its core is located in the alternating magnetic field, which will produce core loss. The winding will also produce copper loss together with other losses when the current is switched on. All these will lead to the temperature increase of the gear motor. The gear motor itself has a thermal dissipation function. When heat generation is equal to thermal dissipation are equal, it will be in a state of balance. If the temperature suddenly rises at this time to break the balance, it will make the temperature continue to rise, thus affecting the normal operation of the gear motor.
2. Temperature rise refers to the temperature difference between the precise planetary gear motor and the environment, which is generally caused by the heat generating of the gear motor. Temperature rise is an important index in the operation of the gear motor, which clearly shows the heating degree of the gear motor. During operation, the sudden temperature rise means that the failure of the gear motor appears, the vent is blocked, or the gear motor is overloaded.
3. Operating temperature refers to the temperature at which the precision planetary gear motor operates when designing its expected service If the operating temperature exceeds the specified temperature for a long time, it will accelerate the aging of insulation material, thus greatly shortening the service life of the gear motor. Therefore, the temperature is one of the main factors affecting the service life of the gear motor during its operation.
4. Gear set loss. Depending on the type of gear set, the efficiency loss may have a slight or significant impact. The loss of spur, helical and bevel gears will decrease from 0.5% to 3%, while the loss of tooth surface gears and bevel gears may be as high as 5%. Hypoid and plane will lose 2%-10% efficiency. Gear sets that may exhibit higher efficiency losses include: cross spiral (5%-50%); cylindrical worm and high-speed hypoid (10%-50%); double-envelope worm and spiral (2%-50%); spiral body (3%- 50%).
5. Seal loss. The seals are used to prevent the lubricating oil from escaping from the planetary reducer and to avoid the penetration of external dust. The static seal used between the housing parts does not affect the efficiency of the planetary gear motor. However, dynamic seals do affect efficiency because they are in contact with rotating components (usually shafts). When the shaft rotates in a fixed seal, friction and heat can reduce efficiency. In order to eliminate the influence of friction, it is vital to lubricate between the shaft and the seal. It should be noted that different seal types will impose different resistance on the shaft. For example, a double-lip shaft seal will have a higher level of ingress protection but will apply more friction than a single-lip seal. Applications that use O-rings as rotary seals may have greater losses than the double-lip shaft seal.
6. Bearing loss. There are many different types and styles of bearings. The effective one is roller bearing without seals. Many different types of seals can be added to the roller bearings, which may increase a certain degree of resistance, thus reducing the efficiency of the overall planetary gear motor. Many different types of bearing greases can also be used and may affect efficiency, depending on the viscosity of the grease. Other bearing types that are less efficient include powder metal bronze, iron bushings and molded plastic bushings.
7. Lubricate the planetary gear motor with grease or oil. There are many changes in grease and oil, which feature high temperature, low temperature, extreme pressure, water resistance, corrosion resistance, etc. A key factor that may affect the micro planetary gear motor efficiency is the viscosity of the lubricant. As the lubricant becomes more viscous or “thicker”, owing to the fall of temperature, more resistance is introduced into the planetary gear motor, thereby reducing its efficiency. The situation is opposite when the temperature rises. The viscosity of the lubricant decreases and the lubrication becomes “thinner”, thereby increasing the efficiency of the planetary gear motor. Lubricant filling or the amount of lubricant added to the planetary reducer will also affect efficiency. Excessive lubrication in a high-speed planetary reducer will cause agitation, resulting in excessive heat generation and efficiency loss. However, insufficient lubrication will cause excessive wear of the gear set.
