Generally speaking, worm gear is a kind of transportati […]
Generally speaking, worm gear is a kind of transportation mechanism. It can be used for power transmission in many industrial fields. The transportation mechanism consists of two parts. It includes worm gear and worm. The form of worm is similar to screw. As a driving device, worm gear has its own unique function. The conveying mechanism has a high transmission ratio. At the same time, it has a great axial force. In addition, its structure is more compact than that of bevel gears. Due to the above characteristics, the drive mechanism is widely used in many places.
Worm gears are used to reduce speed and increase torque. They are very compact and can achieve very high speed ratios, usually 60:1 or higher. Unfortunately, due to the way they operate, they generate a lot of heat and require special lubrication.
The worm wheel and the worm are in contact with each other by sliding instead of rolling. This increases friction, which increases the operating temperature. The working temperature of the worm gear is close to twice that of other spur gears (such as spur gears). Due to sliding, the worm slowly wipes off the lubricating film while meshing with the worm gear. After the worm surface is disengaged, it will absorb more lubricant, but it is difficult to ensure that its surface has a sufficiently thick lubricant film to continue to pass through the load area. As a result, the worm drive requires a high-viscosity lubricant (due to the higher operating temperature) and has good lubricity to overcome the high-load contact between metal and metal.
The advantages and disadvantages of worm gears:
First, let us discuss the advantages of worm gears. Compared with bevel gears, worm gears have a better meshing effect and a higher transmission ratio. Moreover, the worm gear drive is a screw drive. The main form of transportation is geared drive. Therefore, the transmission is more stable and the vibration is smaller. This drive type is very suitable for machines that work under stable working conditions. Last but not least, compared with other transportation machinery, the biggest advantage of worm gear is its self-locking function. When the lead angle of the worm is smaller than the friction angle of the meshing gear, the conveying mechanism will produce reverse self-locking. At this time, the worm can drive the worm wheel, but the worm wheel cannot drive the worm.
Second, let us analyze the shortcomings of worm gears. As far as we know, everything has two sides, just like a coin. This transmission mechanism is no exception. The transmission efficiency of this transportation mechanism is very poor. In addition, the wear is very serious during the transmission process. Why does this transportation mechanism have these shortcomings? It is related to its driving form. The driving form of the worm gear is meshing gear transmission. The fast sliding speed causes the tooth surface to wear. In order to reduce the wear of the tooth surface, this kind of transport mechanism uses expensive materials. Therefore, the cost of the worm gear increases. The price is more expensive.