Worm Gear – Low-Noise Gear Ratio Expert

Worm gears are an important part of the design of many machines and systems. They offer high gear ratios and torque transmission, while taking up only little space in mechanical application thanks to their space-saving design. In order to find the best possible solution for your specific requirements, it is important to select the right components based on the required specifications and performance requirements.

What worm gears are and what they are used for

Worm gears are a torque transfer mechanism and consist of a worm and a gear wheel (worm wheel). Worm gears convert rotary movements into another rotary movement with a very high reduction or transfer ratio and are used to enable high torque at a low speed.

Due to the shape and geometry of the worm gears, they have an extremely low noise and vibration behavior in operation. They are able to provide high torque at low speed of rotation, making them ideal for applications such as lifting and material transport equipment. You can continue working unidirectionally, which means that the worm wheel cannot transfer the torque to the worm.

What components does a worm gear system consist of?

A worm gear consists of the following two main components:

Basics for the selection of worm gears

The calculation principles for worm gears are multidimensional and require a comprehensive understanding of the mechanics and geometry. The most important points when selecting a suitable worm gear are:

The calculation principles for worm gears are multidimensional and require a comprehensive understanding of the mechanics and geometry. The most important points when selecting a suitable worm gear are:

• Gear ratio: The gear ratio of a worm gear is determined by the ratio of the number of teeth (z). To determine, the number of teeth of the worm wheel is divided by the number of turns of the worm.
• Torque transmission: The maximum permissible torque of worm gears is largely determined by the strength of the tooth surfaces and must not be exceeded during application in order to achieve a long service life.
• Engagement distance: The distance between the centres of axle of the worm and worm wheel must be determined.
• Load-bearing capacity: The load-bearing capacity of worm gears is largely determined by the material pairing of the worm and the worm wheel. The load-bearing capacity limits are calculated on the basis of DIN 3996.

Which components are required for efficient worm gears?

Worm gears are mounted on drive shafts, rotation shafts and motor shafts. The worm gear transfers the engine torque to other parts of the system. The fixation on the drive shaft can be carried out, for example, using grub screws, which ensure that the components are securely connected to each other. Bearing housings can be used to ensure permanent positioning of this drive segment. They serve to stabilize the shaft and thus the entire system. The solid interlocking of these components ensures that all elements can work together optimally without causing unnecessary friction forces.

Choose the right lubricant

Due to the high friction between the worm and the worm wheel, worm gears generate more heat than other types of gear units, which must be taken into account when selecting the correct lubrication and cooling. Lubrication in worm gears essentially has the following purposes:

• Reduction of sliding friction
• Temperature regulation
• Protection of the surfaces against corrosion
• Removal of foreign bodies

Different lubrication methods are suitable for the lubrication of worm gears. Choosing the correct lubrication method depends on the sliding speed between the contact surfaces. There are three different lubrication methods: Grease lubrication, immersion lubrication and forced lubrication.

Maintenance of worm gears

Worm gears are of great importance in many construction applications. They are characterized by high precision and the capability to transfer large torques. Regular maintenance is essential for ensuring the longest possible service life and reliability.

One of the most important maintenance activities for worm gears is checking for proper lubrication. Because there is a high friction between the worm and worm wheels, worm gears develop more heat than other types of gear units, which must be taken into account when selecting the correct lubrication and maintenance.

Furthermore, inspecting the tooth flanks is of great importance for maintaining worm gears. These should be checked regularly for wear, damage or deformation. Damaged contact surfaces can lead to an increased material wear and malfunctions.

The following points should be observed during maintenance:

• Check the lubrication: The lubricating oil or lubricating grease must be checked regularly for dirt and contamination and replaced if necessary.
• Cleaning: Before relubricating or replacing the lubricating oil, the gear unit should be thoroughly cleaned to remove foreign bodies and deposits.
• Check for wear: Bearings, seals and contact surfaces should be checked regularly for wear. If necessary, worn parts may have to be replaced.
• Alignment check: Worm gears should be checked regularly for their alignment to prevent abrasion of the teeth.

Regular maintenance allows worm gears to work reliably and efficiently and reach their maximum service life.