Helical Worm Gearboxes – Compact Power with High Torque and Smooth Operation

Helical worm gearboxes combine the benefits of helical gears and worm gears in a single, compact transmission unit. This hybrid design provides the smooth engagement and high efficiency of helical gearing in the first stage and the high gear reduction and right-angle output of worm gearing in the second stage. The result is a quiet, space-saving, and powerful gearbox ideal for demanding industrial applications.

In this article, you’ll discover how helical worm gearboxes work, where they are used, and why Rehfuss Drive Solutions is your ideal partner for robust and efficient hybrid gear units.

What Is a Helical Worm Gearbox?

A helical worm gearbox is a two-stage gear unit that combines:

A helical gear stage (input side)

A worm gear stage (output side)

The helical stage boosts torque and improves the overall efficiency, while the worm stage offers high reduction ratios and a 90° angle drive.

This combination enables better performance than a single-stage worm gearbox, particularly in terms of:

Efficiency

Torque output

Noise reduction

Lifespan

How Does a Helical Worm Gearbox Work?

The motor drives the input shaft, which is connected to a helical gear.

The helical gear stage transmits power to an intermediate shaft with increased torque.

The intermediate shaft drives the worm shaft, which then engages with the worm wheel.

The worm wheel rotates the output shaft at a much slower speed but with high torque.

This staged power transmission reduces friction, enhances efficiency, and allows for high reduction ratios in a compact right-angle gearbox.

Key Advantages of Helical Worm Gearboxes

1. Compact Design with High Reduction

Get high gear ratios in a smaller footprint – ideal when space is limited.

2. Improved Efficiency

Helical pre-stage improves the efficiency of traditional worm drives by up to 10–15%.

3. Smooth, Quiet Operation

Reduced vibration and noise compared to single-stage worm gearboxes.

4. High Torque Output

Capable of handling large loads even in continuous-duty cycles.

5. Right-Angle Drive

Perfect for machines requiring a 90° change in rotation direction.

6. Optional Self-Locking Function

Under certain conditions, the worm gear stage prevents back-driving, providing a natural holding brake.

Typical Applications

Helical worm gearboxes are found in a wide variety of industries and systems where compactness, power, and reliability are critical:

Material handling and conveyors

Packaging equipment

Elevator and lifting systems

Food and beverage processing machinery

Textile and printing machines

Logistics and warehouse automation

Bottle fillers, labelers, and mixers

Materials and Technical Features

Rehfuss helical worm gearboxes are available with the following specifications:

Housing materials: Aluminum (light-duty) or cast iron (heavy-duty)

Gearing materials: Hardened steel and bronze worm wheels

Shaft types: Solid shaft or hollow shaft with shrink disc or keyway

Protection classes: IP54, IP55, IP65 or higher depending on the environment

Lubrication: Long-life grease or oil bath, optionally with food-grade lubricant

Helical Worm Gearboxes vs. Other Gear Types

Helical worm gearbox

Right-angle drive

High torque in compact form

Moderate efficiency (~75–90%)

Smoother and quieter than standard worm gearboxes

Lower backlash possible

Standard worm gearbox

Simple and compact

Lower efficiency (~60–80%)

More friction and heat

Self-locking advantage

Helical gearbox

Parallel shaft configuration

Very high efficiency (>90%)

Requires more space for similar reduction

Helical Worm Gearboxes by Rehfuss Drive Solutions

Rehfuss offers precision-engineered helical worm gearboxes tailored to the demands of modern industrial applications. Our gearboxes feature:

Modular design with wide ratio range

Compatibility with IEC motors, servos, or custom motors

Output options: hollow shaft, solid shaft, torque arm

Coated or stainless steel options for harsh or hygienic environments

Accessories: brakes, encoders, thermistors, and more

Buy Helical Worm Gearboxes Now

Need a reliable, quiet, and compact gear solution with high torque output? Rehfuss helical worm gearboxes offer powerful performance with a small footprint.

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