Worm gear reducers, also known as worm drives, are a type of mechanical transmission system used to reduce speed and increase torque. They achieve this by using a worm screw (a helical gear) that meshes with a worm wheel (a gear with many teeth).

Here's how it works:

1. Rotation: The motor shaft rotates the worm screw.
2. Engagement: The worm screw's threads engage with the teeth of the worm wheel.
3. Friction and ratio: Due to the difference in size and shape between the worm screw and worm wheel, there's a significant friction between the teeth. This friction, combined with the large gear ratio (number of teeth on the worm wheel compared to the worm screw), results in a slow rotation of the worm wheel compared to the worm screw.

Key characteristics of worm gear reducers:

• High torque output: They can achieve very high torque multiplication, making them suitable for applications requiring significant force.
• Self-locking: In most cases, the worm gear reducer acts as a self-locking mechanism. This means the output shaft cannot drive the input shaft (the worm screw cannot be turned by the worm wheel). This is advantageous for applications requiring holding power or preventing backdriving.
• Compact design: They can be relatively compact compared to other speed reduction mechanisms with similar torque capabilities.
• Smoother operation: They generally provide smoother operation than some other gear reduction options.