The main types of gear motor can be classified in two ways: by the electric motor that supplies the power and by the gears that transmit it. AC and DC describe the power and control characteristics; spur, helical, worm, bevel, and planetary describe the gearbox. Understanding both layers helps you compare speed control, torque density, noise, efficiency, shaft direction, size, and cost without confusing unlike products.
| Type | Main difference | Typical advantage | Common consideration |
|---|---|---|---|
| AC gear motor | Runs from alternating current | Reliable for fixed-speed industrial duty | Variable speed may require an inverter and motor compatibility check |
| DC gear motor | Runs from direct current | Convenient speed and direction control | Brushed models require brush maintenance; brushless types need electronic control |
| Spur | Straight teeth on parallel shafts | Simple and economical | Can be noisier at higher speed |
| Helical | Angled teeth engage gradually | Smoother, quieter power transfer | Creates axial force that bearings must support |
| Worm | Screw-like worm drives a wheel at 90 degrees | High ratio in a compact right-angle form | Sliding contact can reduce efficiency and produce heat |
| Bevel or hypoid | Transfers motion between intersecting or offset axes | Efficient right-angle layout | Precision manufacturing and alignment affect performance |
| Planetary | Planet gears rotate around a central sun gear | High torque density in a coaxial package | Usually more complex and costly |
No single design is best for every machine. Power source, required output speed and torque, available space, operating hours, positioning accuracy, environment, and budget determine the right combination.
A geared motor AC unit combines an alternating-current motor—often an induction or reversible motor—with a reducer. AC versions are widely used in conveyors, packaging machines, food-processing equipment, and other installations connected to mains power. They are valued for robust construction and dependable continuous operation.
A gear motor 220V is a common search, but voltage alone is not enough to specify a product. Buyers must also confirm whether the supply is single-phase or three-phase, whether the frequency is 50 or 60 Hz, and whether the motor must reverse or work with a speed controller. The actual nameplate voltage and frequency must match the installation.
A DC gear motor is useful where the machine has a battery or DC supply, or where simple variable-speed and direction control are priorities. Brushed DC units are often economical and easy to drive. Brushless DC versions can offer longer service life and more sophisticated control, but they require compatible electronics.
A gear motor 12V is common in mobile robots, small vehicles, actuators, hobby equipment, and portable machinery. Never select it by voltage and no-load rpm alone. Check rated torque, stall or peak current, continuous current, gearbox load limit, duty cycle, and the capacity of the battery, wiring, fuse, connector, and controller.
For compact industrial AC options, the small gear motor range shows how power, frame size, voltage, and reduction choices can be organized within one product family.
Spur gears have straight teeth and normally connect parallel shafts. Their straightforward construction makes them a practical choice for light automation, vending equipment, small conveyors, and mechanisms where moderate noise is acceptable. They can be efficient, easy to manufacture, and cost-effective.
The tradeoff is abrupt tooth engagement. At higher speed, this can create more noise and vibration than a comparable helical design. A spur reducer is therefore a good baseline choice when price and simplicity matter more than very quiet operation.
Helical gear teeth are angled, so contact builds progressively and several teeth can share the load. This promotes smoother transmission and lower noise, making helical geared drives suitable for production lines and continuous-duty conveyors.
The angled contact generates axial thrust, which the bearings and housing must manage. Manufacturing is also more involved than for basic spur gears. Select helical gearing when smooth running, load capacity, and sound level are more important than the lowest initial price.
A worm gearbox uses a screw-like worm to drive a gear wheel, usually turning the output through 90 degrees. It can achieve a substantial reduction in one stage and fit conveniently into machines where an inline shaft would be awkward.
Because the teeth experience significant sliding contact, worm drives may lose more energy as heat than other designs. Some configurations resist back-driving, but self-locking must never be assumed from the word “worm.” Lead angle, friction, lubrication, wear, vibration, and load all influence whether the output can drive the input. Use a brake when holding a load is safety-critical.
Bevel gears transmit power between intersecting shafts, while hypoid designs use offset shafts. Both can provide a compact right-angle arrangement. They are often selected for conveyors and packaging systems that need efficient power transfer around a machine corner.
Compared with worm gearing, bevel or hypoid units may offer better efficiency, depending on the exact design. Their geometry and bearing loads require precise manufacturing and correct lubrication, so published ratings and mounting instructions matter.
A planetary stage places planet gears around a central sun gear inside a ring gear. Multiple gear contacts share the load, producing high torque capacity in a compact coaxial layout. Low-backlash versions are used in robotics, servo axes, and positioning equipment.
The advantages come with greater component count, manufacturing complexity, and often a higher gear motor price. Planetary gearing is most valuable when compact size, torque density, stiffness, or precise motion outweighs the need for the cheapest solution.
Within the same AC family, power can provide a useful first filter. A compact mechanism may start with a 15W small AC gear reducer motor, while a light conveyor may suit a 40W model. Applications requiring more output can be compared against a 90W model or a 160W model.
Wattage does not replace sizing. Two units with the same motor power may produce very different output speed and torque because their ratios and gearbox ratings differ. Verify continuous and peak torque, service factor, duty cycle, radial and axial load, mounting, and thermal limits.
When comparing suppliers, review the full Products range and learn about manufacturing capabilities on About Tenchuan. A useful quotation should match the same technical specification across every candidate.
The important differences between geared drives are not captured by one label. First match the AC or DC power and control system, then choose the gear architecture and shaft layout that satisfy torque, speed, space, efficiency, noise, and accuracy requirements. Visit the Tenchuan home page for an overview, or contact Tenchuan with your application data for model selection and current pricing.
There is no universal winner. Efficiency varies with gear geometry, number of stages, ratio, load, speed, lubrication, and manufacturing quality. Compare efficiency or input-power data at the intended operating point.
Planetary designs are often considered for high torque density, but the correct choice must also meet speed, duty, backlash, bearing-load, thermal, and budget requirements.
No. Metal often suits higher loads and temperatures, while engineered polymers can reduce noise, weight, and cost. The right material depends on the operating conditions and design targets.
Gear type, ratio, materials, precision, bearings, sealing, motor technology, controller, brake, certifications, quantity, and customization can all change the price.
Send output rpm, continuous and peak torque, power supply, duty cycle, mounting, shaft loads, available space, environment, control requirements, quantity, and any required drawing or certification.
The seven types described above split across our ranges by load. Spur and helical units in 4RK, 5RK and 6RK frames make up the small AC gear reducer motors series from 15W to 300W; above 300W the medium gear reducer motors range covers 400W to 3700W. Bevel (right angle) configurations are grouped under the right angle gear reducer motors category.
To compare frame sizes within the small range, the 15W–300W AC small gear motor page lists them side by side; the 5GU right angle gear reducer motor is a concrete example of the bevel type at 40W–140W.
Need help mapping a machine to a type? Use the contact form and describe the motion.
