Why is the Reduction Ratio of the Miniature Reducer Motor Very Important?

The main structure of miniature reduction motor is composed of motor and reducer. The motor drives the rotor movement of the reducer, gradually transmitting the driving force through the gear of the reducer, enabling the output shaft to achieve slow rotation. Therefore, the core is the speed reducer. The speed ratio of the reducer is very important, so what is the speed ratio of the reducer?

Planet reduction motor

The main structure of planetary reduction motor includes shell, planetary frame, planetary gear, solar gear and internal gear. Among them, the planetary frame is fixed on the output shaft and connected to the solar gear through the planetary gear. The inner gear is connected to the motor through the input shaft to complete the assembly of the entire transmission structure. Planetary gear is composed of multiple gears, which can make full use of the advantages of double gear transmission, reduce transmission error and improve the actual transmission efficiency. The sun gear is located in the center, connected to the planetary gear, and is driven by rotating the gear between the planetary gear and the sun gear. The inner gear is surrounded by a planetary frame, which transfers the torque by connecting the input shaft to complete the transmission process. Its operation principle is using the multi-gear transmission structure of planetary gear to reduce the torque change on the input shaft and pass to the output shaft, so as to achieve higher control accuracy and torque output. In addition, due to its structural characteristics, its small noise, high output torque, high reliability advantages, can meet the different control needs of various mechanical equipment.

We first understand the next reducer, the reducer is mainly composed of five parts: gear, bearing, box, shaft, oil seal. The gear is the core component of the reducer, which is used to transfer the power from the high speed input shaft to the low speed output shaft. The gears transfer force through engagement to achieve the effect of reduction. The bearings are used to support the input shaft, output shaft and gears to ensure their safe operation. The box is the shell of the reducer, which plays the role of fixing gears and bearings and preventing oil leakage and so on. The shaft is the key component connecting the gear and the bearing, bearing important axial and radial loads. The oil seal is used to prevent oil leakage and ensure that the oil runs to the gears and bearings. The operation principle of the reducer is mainly realized through the power transmission generated by the gear engagement. The input shaft outputs the power to the gear, and the high-speed rotating gear then transfers the power to the output shaft through engagement, while making the output shaft rotate at a slower speed, so as to achieve the effect of reduction. During the whole operation process, the gear and the bearing and the box are lubricated by oil to ensure a smooth and stable operation. In addition, there is a reduction is also a kind of the transmission ratio (the transmission ratio of the reducer), simply put, it is the ratio of the reducer instant input speed and output speed, in the calculation formula with "i", the general ratio symbol is ":" is the ratio of the input and output speed connected. This may seem a little complicated for the layman, let's take a simple example, if the output speed of the micro motor is 7500 rpm (r/min), but only 60 rpm (r/min) after passing the reducer, then the reduction ratio is i=125:1.

Planet reduction box

How does this reduction ratio come about? In fact, it is just a very simple formula, we can directly put 750060 to get the calculation result of 125, that is, the reduction ratio = the input speed and the output speed.

In addition to the above simple calculation method, you can also use a method called the gear system calculation method:

A. Gear parameter calculation

Mous, tooth number and partition circle diameter. According to the torque and bearing load capacity, determine the number and analog of all levels of wheels in the transmission. The separation circle diameter of the gear is calculated. Central distance calculation. It is very important to determine the center distance of gear transmission, and the choice of center distance is different in different cases. Generally speaking, the calculation of the center distance needs to be calculated according to the transmission ratio, tooth number and modulus number. Calculation of the tooth shape parameters. By designing the tooth shape of the gear transmission, we can ensure the stability and reliability of the gear transmission. In the selection of tooth parameters, the module and pressure angle are considered to ensure the gear has good transmission performance.

B. Speed ratio calculation

Speed ratio is one of the most important parameters in gear transmission design. The speed ratio is calculated by the reciprocal of the transmission ratio, which is the ratio of the speed of the input shaft to the speed of the output shaft. If the speed of the input shaft is n1 and the output shaft is n2, then the speed ratio is n1 / n2.

C.Transmission ratio calculation

Transmission ratio is another important parameter in gear transmission. Through the design of transmission ratio, can achieve different speed, different torque transmission. The calculation of transmission ratio needs to be calculated according to the gear parameters of the input shaft and output shaft. The calculation formula of transmission ratio is transmission ratio = number of output shaft gear teeth / number of input shaft gear teeth.

D. Actual transmission ratio calculation

In gear transmission, due to gear manufacturing error and assembly error, the actual transmission ratio may have some error. In order to ensure the accuracy and stability of gear transmission, the actual transmission ratio is calculated. The actual transmission ratio is calculated by: the actual transmission ratio = output shaft speed / input shaft speed * output shaft gear diameter / input shaft gear diameter.

Planetary reducer gear

What does the reduction ratio do? The reduction ratio plays a decisive role in the final output torque of the reducer. Firstly, if the torque is increased, the reduction ratio can convert the high speed and low torque of the drive wheel into low speed and high torque, so that the motor output torque applied in large mechanical equipment can be effectively increased, thus making the equipment more stable and reliable work; secondly, improving the transmission efficiency, the reduction ratio increases the torque of the output shaft when the speed decreases, thus transferring the energy to the driven device more effectively. At the same time, the reduction ratio can also reduce the friction loss in the mechanical transmission, thus improving the transmission efficiency; next, the protective equipment, the reduction ratio can help slow down the wear speed of the mechanical device, thus extending the service life of the mechanical equipment. In addition, the reduction ratio can also protect the impact and pressure wave occurring during the initial start of the equipment, and reduce the vibration and noise caused by sudden large torque. Finally, different mechanical equipment adapt to different process requirements. For example, some equipment requiring strong torque output needs a high reduction ratio, while for some equipment requiring high speed, the reduction ratio needs to be reduced. Different transmission effects and process requirements can be achieved by changing the reduction ratio. The torque of the reducer can also be calculated, through the formula: the reducer torque =9550 motor power motor input speed ratio use coefficient. Note: This formula requires the power, speed ratio and use coefficient of the micro motor to calculate the torque of the reducer, these micro motor manufacturers have, and will be calculated for you.

Planet reducer Calculation method of the output torque of the speed reducer. The calculation formula of the reducer is: T"=T×η1×η2×ηr Among them, T is the output torque of the motor; η 1 is the rotational transmission efficiency between the motor seat and the input shaft of the reducer, usually the value is 0.9-0.95; η 2 is the internal transmission efficiency of the reducer, usually the value is 0.85-0.95; η r is the rotational transmission efficiency between the output shaft of the reducer and the load, usually the value is 0.8-0.95. According to this formula, we can calculate the output torque of the reducer. Finally, we need to calculate the output torque of the motor. The output torque of the motor is: T=P/ω Among them, P is the output power of the motor in watt and ω is the angular speed of the motor in radian / second. This formula can be used to calculate the output torque of the motor.

The above are some professional knowledges on reduction ratio by VSD Motors. For more relevant information, please contact us.