Slotless Motor
Motor construction selected around diameter, speed, torque, thermal conditions and service-life target.
Slot-free stator · smooth brushless motion
Slotless Brushless Motors & Drives
Electronically commutated motor and drive platforms for compact applications requiring smooth torque, low noise, high speed and long operating life.
Dedicated brushless architecture
Why Choose a Slotless Motor?
Removing conventional stator teeth and slots reduces cogging, torque ripple and magnetic noise. The result is a compact brushless platform suited to continuous precision motion.
Feedback & Control
Hall sensors, encoder and electronic controller matched for commutation, speed or position regulation.
Complete Geared Drive
Inline or angular gearhead, shaft and mounting interface configured as one motion assembly.
Representative selection data
Slotless Motor Performance Envelope
The 16–80 mm reference platforms cover compact high-speed duties through to higher-torque motor-and-drive systems. Configurations up to 87 mm are developed against the required winding, length, cooling and controller.
| Motor diameter | Nominal voltage | Rated power | Typical speed | Continuous torque | Peak torque* | Maximum efficiency | Typical length |
|---|---|---|---|---|---|---|---|
| Ø16 mm | 12–24 VDC | 20–50 W | 15,000–55,000 rpm | 5–25 mNm | 15–75 mNm | 80–90%+ | 30–50 mm |
| Ø22 mm | 12–48 VDC | 30–100+ W | 10,000–50,000 rpm | 20–50 mNm | 60–150 mNm | 85–91% | 35–60 mm |
| Ø26 mm | 12–48 VDC | 30–100 W | 8,000–30,000 rpm | 30–70 mNm | 90–210 mNm | 80–90% | 40–60 mm |
| Ø32 mm | 12–48 VDC | 50–150 W | 8,000–25,000 rpm | 50–120 mNm | 150–360 mNm | 85–92% | 40–70 mm |
| Ø45 mm | 24–48 VDC | 100–400 W | 5,000–15,000 rpm | 0.10–0.40 Nm | 0.3–1.2 Nm | 85–92% | 60–100 mm |
| Ø80 mm | 24–72 VDC | 300 W–1.2 kW | 3,000–10,000 rpm | 0.5–2.5 Nm | 1.5–7.5 Nm | 85–93% | 80–160 mm |
01Use of the values
The table shows a representative family envelope across different windings, motor lengths and thermal designs—not one simultaneous operating point.
02Peak torque
Peak torque is a short-duration capability governed by controller current, winding temperature, cooling and the application duty cycle.
03Final technical release
SDT confirms the continuous and peak operating points for the selected motor, controller and duty before quotation and technical release.
Coreless and slotless motor technical dataReview the representative performance ranges and application-selection information.
Technical PDFRequest Technical Datasheet →Engineering selection criteria
Match the Motor, Drive and Load
Selection is based on the complete operating system rather than diameter alone. SDT checks the motion duty, electrical control and mechanical output together before confirming a production configuration.
01
Establish the motion duty
Define voltage, speed range, continuous and peak torque, acceleration, duty cycle and expected operating life.
Output: traceable performance requirement02
Match feedback and drive
Select Hall sensing or encoder feedback with the controller voltage, current, commutation method and protection strategy.
Output: compatible motor-drive architecture03
Confirm mechanical output
Validate the shaft, bearings, mounting, gear ratio, backlash, output loading and thermal path in the installed equipment.
Output: machine-ready drive configurationFeatures and customer benefits
Smooth, Quiet and Durable Motion
Low cogging
The slot-free stator reduces torque ripple for smooth low-speed motion and positioning.
Quiet operation
Reduced electromagnetic excitation helps limit vibration and acoustic noise.
High-speed capability
Electronic commutation and low magnetic losses support demanding rotational speeds.
Long service life
Brushless operation removes mechanical commutator wear from the motor.
Compact power density
Efficient winding use provides useful output from a small cylindrical envelope.
Matched drive system
Controller, feedback and gearhead are selected around the motor and operating duty.
Application-specific engineering
Available Customisation
Electrical design
Voltage, winding, speed constant and current matched to the controller.
Electronic control
Drive voltage, current, commutation and protection selected around the operating duty.
Feedback
Hall sensors or encoder configured for speed and position requirements.
Mechanical design
Diameter, stack length, shaft, flange, bearings and connectors adapted to fit.
Gearhead integration
Ratio, backlash, efficiency and output loads assessed with the motor.
Production supply
Validated motor-drive configuration documented for repeatable OEM delivery.
Define Your Slotless Motor & Drive
Share the voltage, speed, torque, envelope, duty, life, feedback and output-interface requirements.