Worm Gearboxes
21.05.2025
Worm Gearboxes – Compact Solutions with Self-Locking Capability
Worm gearboxes are a widely used type of gear unit, known for their right-angle drive configuration, high reduction ratios, and self-locking ability. These gearboxes are compact, quiet, and reliable, making them ideal for applications where space is limited and reverse motion must be prevented. In this article, you’ll learn what a worm gearbox is, how it works, its advantages, and where it is typically used. We’ll also show you why Rehfuss Drive Solutions is your reliable partner for high-quality worm gear technology.
What Is a Worm Gearbox?
A worm gearbox consists of two main components:
A worm shaft (similar to a screw)
A worm wheel (a toothed gear that meshes with the worm)
The worm shaft is positioned at a 90-degree angle to the worm wheel, creating a right-angle drive. The rotation of the worm shaft drives the worm wheel, but the reverse motion (worm wheel driving the worm shaft) is generally not possible – this feature is known as self-locking.
How Does a Worm Gearbox Work?
When the worm shaft rotates, its threads engage with the teeth of the worm wheel, causing the wheel to turn. Due to the sliding contact between the two components (rather than rolling contact like in helical gears), the motion is smooth and quiet, but it generates more heat and friction.
The gear reduction is achieved through the number of threads on the worm and the number of teeth on the worm wheel:
Gear Ratio = Number of Worm Wheel Teeth / Number of Threads on Worm
For example, a worm with 1 thread driving a 40-tooth worm wheel gives a 40:1 ratio in a single stage.
Advantages of Worm Gearboxes
1. High Reduction Ratios in One Stage
Worm gearboxes can achieve reduction ratios of up to 100:1 or more in a single gear stage.
2. Self-Locking Capability
In many cases, the worm gear cannot be back-driven, providing a natural brake for vertical or safety-critical systems.
3. Right-Angle Configuration
Perfect for applications with space constraints or specific shaft alignment requirements.
4. Smooth and Quiet Operation
Due to the sliding action between worm and wheel, worm gearboxes are quieter than most other gearbox types.
5. Compact Design
High reduction in one compact unit makes it easy to install and integrate into machinery.
Common Applications of Worm Gearboxes
Worm gearboxes are ideal for systems where compactness and control are more important than peak efficiency. Typical use cases include:
Conveyors and material handling systems
Elevators and hoists
Packaging machinery
Gates and lifting equipment
Mixers and turntables
Medical and lab equipment
Garage doors and shutters
Worm Gearboxes vs. Other Gear Types
Worm Gearbox
Right-angle drive
High gear ratios
Self-locking possible
Lower efficiency (60–85%)
Compact and quiet
Helical Gearbox
Parallel or right-angle drive (with bevel stage)
High efficiency (up to 98%)
No self-locking
More dynamic
Bevel Gearbox
Right-angle drive
Efficient and rugged
No self-locking
More costly for high ratios
Materials and Lubrication
Rehfuss worm gearboxes are made with high-quality materials for long-lasting performance:
Housings: Aluminum for light-duty or cast iron for heavy-duty applications
Gears: Hardened steel worm and bronze worm wheel for optimal wear resistance
Lubrication: Grease-filled or oil-bath versions, often maintenance-free (lifelong lubrication)
Optional: Food-grade oil or synthetic lubricants for specific environments
Worm Gearboxes from Rehfuss Drive Solutions
Rehfuss offers a complete range of worm gearboxes, designed for smooth performance, durability, and flexibility. Our models are available with:
Hollow or solid output shafts
Torque arms or foot/flange mounting
IEC motor flanges or fully integrated motors
Optional accessories such as brakes, encoders, or thermal protection
Custom designs for ATEX, hygienic, or outdoor environments
Buy Worm Gearboxes Now
Looking for a quiet, compact, and self-locking gearbox solution? Rehfuss worm gearboxes deliver precision, durability, and versatility for industrial applications.