Core technologies and common faults of worm reduction gearbox

1. Definition of worm reduction gearbox

A worm reduction gearbox is a power transmission mechanism that uses a gear speed converter to reduce the number of revolutions of the motor to the desired number of revolutions and obtain a larger torque. It is widely used in the machinery industry, home appliance industry and automation equipment in the mechanism used to transmit power and motion.

2. Working principle of worm reduction gearbox

The operating principle of the worm reduction gearbox is mainly based on the precise meshing transmission between the worm and the worm wheel. The worm reducer drives the worm wheel to rotate by the rotation of the worm, thereby achieving the effect of reducing speed and increasing torque. Its core components include worm wheels, worms, bearings, and housings. The worm is like a spiral, and the worm wheel meshes with it. When the worm rotates, the worm wheel rotates with it, achieving the purpose of reducing speed and increasing torque.

3. Core technology of worm reduction gearbox

1. Annular surface enveloping transmission technology: Adopting annular surface enveloping worm gear structure, the contact area is increased (up to 85%) through multi-tooth meshing design, and high torque density (500Nm/kg) is achieved, which is more than 3 times higher than the traditional solution.

2. Miniaturized manufacturing process: Through the compact design of 4.5-10mm center distance, the volume is reduced by 40%, the weight is only 9-49g, and the torque output is 1-3N·m. This miniaturized technology breaks the contradiction between the volume and performance of traditional reducers and provides a solution for smart machinery. ‌

3. High-precision tooth shape design: The asymmetric tooth profile design reduces the center distance by 30%, the surface roughness Ra0.4μm, and the gradient composite coating technology extends the life of the worm gear by 2.3 times. The laser processing technology further optimizes the uniformity of the tooth surface contact stress and improves the load-bearing performance by 38%. ‌

4. Self-locking characteristics: The self-locking function is achieved by relying on friction and lead angle design, and only one-way transmission is allowed, and reverse drive is impossible. This feature plays a key protective role in safety scenarios such as lifting machinery. ‌

5. Efficient heat dissipation and lubrication: The embedded heat sink and forced oil cooling system (≥12L/min) are used to accurately control the temperature rise Δ45℃ to ensure long-term stable operation. Lubricant additive technology allows the gear oil to adhere to the surface to form a protective film when the machine is stopped, reducing direct contact wear.

4. Common faults of worm reduction gearbox

1. Heat and oil leakage: In order to improve efficiency, worm reduction gearbox generally uses non-ferrous metals for worm wheels and harder steel for worms. Since it is a sliding friction transmission, it will generate higher heat during operation, causing differences in thermal expansion between the various parts and seals of the reducer, thereby generating gaps between the mating surfaces, and the oil becomes thinner due to the increase in temperature, which is easy to cause leakage.

2. Worm wheel wear: The worm wheel is generally made of tin bronze, and the paired worm material is generally hardened to HRC45-55 with 45 steel, and ground to a roughness of Ra0. 8 fcm by a worm grinder. When the reducer is operating normally, the worm is like a hardened "file", constantly filing the worm wheel, causing the worm wheel to wear. If the wear rate is fast, it is necessary to consider whether the reducer is selected correctly, whether it is overloaded, and the material of the worm wheel and worm.

3. Helical gear wear: generally occurs on vertically installed reducers, which is mainly related to the amount of lubricant added and the choice of lubricant. When installed vertically, it is easy to cause insufficient lubricant oil. When the reducer stops running, the transmission gear oil between the motor and the reducer is lost, and the gears cannot get the proper lubrication protection. During startup or operation, they cannot get effective lubrication, resulting in mechanical wear or even damage.

4. Bearing damage: When the reducer fails, even if the reducer box is well sealed, the factory often finds that the gear oil in the reducer has been emulsified, and the bearings have been rusted, corroded, and damaged. This is because the gear oil condenses when the gear oil is cooled from hot during the operation and shutdown of the reducer; of course, it is also closely related to the bearing quality and assembly process methods.