A reducer is a mechanical transmission device that is applied in multiple fields, involving industries such as ships, water conservancy, power, engineering machinery, and petrochemicals. There are also many types of reducers, and if you want to choose a suitable reducer for your industry, you need to understand the advantages and disadvantages of each type of reducer. Next, let's analyze the advantages and disadvantages of various types of reducers:
The worm gear reducer is composed of an input worm gear and an output worm gear, characterized by high torque transmission, high reduction ratio, and a large range. The reduction ratio of a single stage transmission is 5-100; The transmission mechanism does not belong to coaxial input and output, which is difficult to apply and has low transmission efficiency, not exceeding 60%. Due to its relative sliding friction transmission, the torsional rigidity value of the worm gear reducer is slightly lower, and the transmission components are prone to wear and tear, with a short working life. Additionally, the reducer is prone to temperature rise, so the allowable input speed is not high (2000rpm), which limits the use of the worm gear reducer.
Assisting servo motors in increasing torque: The technological development of servo motors has led to a speed increase of over 3000rpm, from high torque density to even high power density. Due to the increase in speed, the power density of servo motors has significantly increased. This means that whether the servo motor needs to be paired with a reducer is mainly determined by the application requirements and cost considerations. This is necessary when the load must be moved and precise positioning is required. Generally, automation equipment such as aviation, satellites, medical, military technology, wafer devices, robots, etc. Their common feature is that the torque required to move the load often exceeds the torque capacity of the servo motor itself. By using a reducer to increase the output torque of the servo motor, this problem can be effectively solved.
The way to increase output torque may be to directly increase the output torque of the servo motor, but this method not only requires the use of expensive magnetic materials, but also requires the motor to have a stronger structure. The increase in torque is proportional to the increase in control current. At this time, using larger drivers, increasing the specifications of power electronic components and related electromechanical equipment will also significantly increase the cost of the control system.
Increasing the power of the servo motor is also a way to increase the output torque. The power density of the servo system can be increased by doubling the speed of the servo motor, without the need to increase the specifications of control system components such as drivers, which means there is no need to increase additional costs. And this requires the use of a gearbox to achieve the goal of reducing speed and increasing torque. So, the development of high-power servo motors requires the use of reducers instead of omitting them.
The basic structure of a harmonic gear reducer consists of a rigid inner gear ring, a flexible outer gear ring, and a harmonic generator. The working principle is based on a harmonic generator as the input component, a rigid inner gear ring as the fixed component, and a flexible outer gear ring as the output component. Among them, the flexible outer gear ring material is special, with thin inner and outer walls, which is the technical core of this type of reducer. Currently, there is no manufacturer of harmonic gear reducers in Taiwan. The SPB series "planetary reducer with few tooth differences" produced by the involute line has mechanical output characteristics between harmonic gears and swing line needle transmission, and can also achieve zero backlash, making it the closest product to harmonic gear reducers in the industry.
The characteristic of harmonic reducer is its high transmission accuracy and low transmission backlash value. The reduction ratio is high and the range is large, with a single transmission reduction ratio of 50-500. In addition, the transmission efficiency is higher than that of worm gear reducers, and the efficiency of single-stage transmission is 65-80% depending on the reduction ratio. Due to its flexible transmission, the torsional rigidity value is low, the working life of the flexible outer gear ring is short, and the reducer is prone to heat generation and temperature rise. Therefore, the allowable input speed is not high, and can only reach 2000rpm, which is its disadvantage.
