What Are Frameless Torque Motors?
Frameless torque motors are direct-drive motor kits consisting of stator and rotor components designed to be built directly into the customer’s mechanical structure. Compared with conventional housed motors, frameless motors allow engineers to create more compact, lightweight, and highly integrated motion systems. This design approach is widely used in robotics and other advanced applications where space efficiency, torque density, and structural flexibility are critical.
At SDM Magnetics, our frameless torque motor series is developed for equipment that requires compact size, light weight, and high power output. These motors are especially suitable for robotic joints, robot dog joints, automated equipment, unmanned aircraft, and navigation systems where efficient integration and reliable torque delivery are essential.
Compact and Modular Design
One of the main advantages of SDM frameless torque motors is their compact electromagnetic package. The low-profile structure allows the motor to be integrated directly into the equipment, helping designers reduce overall actuator size and simplify the mechanical layout. This is particularly important in robotic systems where every millimeter of space matters.
Our frameless torque motor series supports seven frame sizes and three winding options, giving engineers more flexibility during system design. The modular platform makes it easier to optimize the motor for torque, speed, voltage, and installation space. The result is a compact but powerful drive solution with excellent torque density, strong structural rigidity, and solid thermo-mechanical stability for long-duty operation.
Optimized Magnetic Circuit for Efficient Torque Output
SDM frameless torque motors are built with premium electrical steel laminations and high-grade NdFeB magnets, including 58SH, 54UH, and other suitable magnet grades depending on project requirements. Optional Halbach array magnetic circuit designs are also available for applications that require enhanced magnetic field utilization and improved electromagnetic performance.
Combined with multiple standard winding configurations, the optimized magnetic circuit supports efficient, stable, and responsive torque output across the speed range. This makes the motor series well suited for demanding dynamic systems such as robot actuators, precision motion equipment, and compact automation modules.
High Continuous Torque for Demanding Duty Cycles
These motors are purpose-built for continuous and demanding operation. In robotic joints, machine tools, and industrial automation systems, stable continuous torque is often more important than short burst output alone. SDM frameless torque motors are designed to provide dependable continuous torque performance over extended operating periods, helping equipment maintain accuracy, responsiveness, and repeatability in real working conditions.
Typical performance range includes:
Rated power: 700 W – 1500 W
Rated voltage: 24 V – 100 V
48 V common configuration
Peak torque: 1 Nm – 40 Nm
This performance range makes the series suitable for a wide variety of motion control platforms, from compact robotic actuators to customized embedded motor systems.
Frameless Torque Motors Data Table
Type | Peak Standstill Torque (Nm) | Peak Standstill Current (A) | Peak Standstill Voltage (V) | Max No-load Speed (rpm) | Cont. Standstill Torque (Nm) | Cont. Standstill Current (A) | Cont. Standstill Voltage (V) | Rated Power Torque (Nm) | Rated Power Speed (rpm) | Resistance (Ω) | Back EMF Coefficient (v/rpm) | Torque Coefficient (Nm/A) | Moment of Inertia | Weight (kg) |
SDM-FL52-20 | 1.2 | 5.9 | 48 | ≥2000 | 0.37 | 1.8 | 10.6 | 0.25 | 1650 | 1.4 | 0.0226 | 0.205 | 1.01 | 0.26 |
SDM-FL52-30 | 1.15 | 8 | 48 | ≥3000 | 0.37 | 2.6 | 7.3 | 0.25 | 1700 | 5.6 | 0.0159 | 0.144 | 1.01 | 0.26 |
SDM-FL52-40 | 1.2 | 12 | 48 | ≥4000 | 0.37 | 3.6 | 5.5 | 0.25 | 2500 | 2.7 | 0.0115 | 0.1 | 1.01 | 0.26 |
SDM-FL60-36 | 2.1 | 18.4 | 48 | ≥3600 | 0.7 | 6.15 | 5.1 | 0.48 | 3400 | 0.83 | 0.012 | 0.114 | 1.81 | 0.31 |
SDM-FL60-38 | 1.7 | 30 | 24 | ≥3800 | 0.48 | 8.35 | 2.95 | 0.33 | 3300 | 0.35 | 0.0063 | 0.057 | 1.41 | 0.25 |
SDM-FL60-50 | 1.6 | 21 | 48 | ≥5500 | 0.63 | 7.88 | 3.8 | 0.45 | 5000 | 0.48 | 0.0087 | 0.08 | 1.81 | 0.31 |
SDM-FL76-28 | 2.81 | 38 | 24 | ≥2800 | 0.95 | 12.7 | 1.99 | 0.7 | 2600 | 0.17 | 0.008 | 0.075 | 3.04 | 0.48 |
SDM-FL76-35 | 3.93 | 40 | 48 | ≥3500 | 1.77 | 18 | 3.1 | 1.15 | 3300 | 0.17 | 0.014 | 0.983 | 5.64 | 0.82 |
SDM-FL76-40 | 3.5 | 30.5 | 48 | ≥4000 | 1 | 8.85 | 3.2 | 0.7 | 3650 | 0.39 | 0.0125 | 0.11 | 3.04 | 0.48 |
SDM-FL85-42 | 1.7 | 32.8 | 24 | ≥4200 | 1.2 | 23.2 | 1.5 | 0.9 | 3700 | 0.065 | 0.0057 | 0.051 | 10.8 | 0.38 |
SDM-FL85-41 | 3.6 | 35 | 48 | ≥4100 | 1.75 | 17 | 3.15 | 1.3 | 3700 | 0.18 | 0.011 | 0.103 | 14.4 | 0.51 |
SDM-FL85-42 | 9.3 | 91.3 | 48 | ≥4200 | 3 | 29.5 | 2.5 | 2.2 | 3900 | 0.085 | 0.011 | 0.101 | 21.6 | 0.74 |
SDM-FL98-40 | 3.25 | 30 | 48 | ≥4000 | 1.3 | 12 | 4.6 | 0.85 | 3700 | 0.38 | 0.0123 | 0.11 | 21.5 | 0.56 |
SDM-FL98-30 | 6.43 | 50 | 48 | ≥3300 | 2.7 | 21 | 3.6 | 1.75 | 3200 | 0.17 | 0.014 | 0.13 | 33.6 | 0.8 |
SDM-FL98-10 | 13.14 | 25 | 60 | ≥1000 | 4.1 | 7.8 | 10.2 | 2.67 | 916 | 1.31 | 0.058 | 0.53 | 51.5 | 1.28 |
SDM-FL129-29 | 10 | 66.5 | 48 | ≥2900 | 3.5 | 23.3 | 2.38 | 2.3 | 2700 | 0.11 | 0.165 | 0.15 | 59 | 1.2 |
SDM-FL129-06 | 39.23 | 57 | 48 | ≥630 | 11.7 | 17 | 4.8 | 7.6 | 590 | 0.28 | 0.0754 | 0.69 | 221 | 4 |
SDM-FL129-18 | 28.75 | 57 | 100 | ≥1800 | 9.1 | 18 | 4.1 | 5.9 | 1700 | 0.23 | 0.0553 | 0.5 | 165 | 2.8 |
Intelligent Thermal Management
Thermal control is critical in high-performance robotics and integrated motion systems. SDM frameless torque motors are engineered to handle thermal loads generated during continuous operation while keeping winding temperatures reliably below 155 °C. Effective thermal design helps extend motor life, improve operational reliability, and support more stable output under repeated or long-duration duty cycles.
For compact robotic equipment, good thermal behavior is especially important because the motor is often embedded directly into the actuator structure. Our engineering team can also support customers in evaluating integration conditions to help optimize thermal dissipation and long-term system stability.
Fast Integration and Design Flexibility
A key benefit of frameless torque motors is integration freedom. Instead of adapting a standard housed motor to the machine, engineers can build the motor directly into the structure and optimize the full actuator layout. SDM supports this design approach with a wide selection of frame sizes, winding combinations, and customization possibilities.
From standard configurations to project-specific solutions, we can support:
Winding customization
Mechanical interface adaptation
Lead length adjustment
Multiple core lengths for each frame size
Application-oriented design support
This flexibility helps customers match the motor more precisely to the mechanical architecture, control system, and space constraints of the final product.
Designed for Robotics and Advanced Equipment
SDM frameless torque motors are mainly used in:
Industrial robots
Robot dog joints
Robotic actuator modules
Automated equipment
UAV and unmanned aircraft systems
Navigation and guidance systems
Precision motion equipment
Compact industrial automation platforms
For robotic joints and embedded actuators, the combination of high torque density, compact size, and direct integration can help reduce mechanical complexity while improving overall system efficiency.
Why Choose SDM Frameless Torque Motors?
SDM Magnetics combines motor electromagnetic design capability with material knowledge and customization support. Our frameless torque motor series is designed not only for performance, but also for practical integration into real customer systems. Whether you are developing a robot joint, a lightweight actuator, or a compact direct-drive platform, we can support your project with flexible motor configurations and engineering-oriented cooperation.
Key benefits include:
Compact, frameless design for direct integration
High torque density in a lightweight package
Seven frame sizes and three winding options
Premium magnetic materials and optimized magnetic circuit
Reliable thermal performance for continuous operation
Flexible customization for different system architectures
Suitable for robots, UAVs, automated equipment, and navigation systems
Contact Us for Custom Robot Motor Solutions
If you are looking for a frameless torque motor solution for robotics or compact motion systems, SDM Magnetics can help. Send us your project requirements, installation space, target torque, voltage, cooling condition, and operating cycle, and our engineering team will recommend the most suitable motor configuration for your application.
FAQ
What is a frameless torque motor?
A frameless torque motor is a motor kit made of separate stator and rotor components that can be integrated directly into the customer’s equipment instead of using a traditional housed motor.
Why are frameless torque motors used in robots?
They help engineers create compact, lightweight, and highly integrated actuators with strong torque output, making them ideal for robot joints and other advanced motion systems.
Can SDM frameless torque motors be customized?
Yes. SDM can support different frame sizes, winding options, mechanical interfaces, lead lengths, and other custom requirements based on your application.
What applications are these motors suitable for?
They are suitable for robotics, robot dog joints, automated equipment, unmanned aircraft, navigation systems, and other compact direct-drive motion systems.
What voltage range is available?
Typical rated voltage range is 24 V to 100 V, with 48 V being a common configuration.
What torque range can SDM provide?
The typical peak torque range of this series is 1 Nm to 40 Nm, depending on model size and configuration.
