Frameless Motor Compact & Lightweight
Frameless Motor
Alva frameless motors consist of a stator and a rotor, enabling direct integration into the housing of the application. This results in a more compact, seamless, and integrated design. The frameless motor itself is exceptionally compact, lightweight, and power-dense - benefits made possible by Alva’s patented FiberPrinting™ manufacturing technology. This advanced technique produces slotless stator mats with a high copper fill factor and non-skewed windings. When paired with a Halbach array rotor, the result is a highly efficient electric motor.
These motors are distinguished by a high motor constant per unit mass, typically outperforming slotted motors of the same diameter. Thanks to their slotless design, they exhibit virtually no cogging torque and offer highly linear torque characteristics across the entire load spectrum. Additionally, the thin, slotless topology with a large inner diameter allows for the integration of gears, encoders, sensors, and other components in the center - an especially attractive feature when designing compact systems.
SlimTorq™
Frameless Motors
Alva’s standard SlimTorq™ product range includes several different sizes, from the smallest at 25 mm in diameter to the largest at 160 mm. Most sizes are available in two configurations: a lightweight version and a maximum torque version. Each motor can be produced with termination options in either a radial or axial direction.
Additional options include integrated temperature sensors or Hall effect sensors, as well as various stator winding configurations to optimize the motor for a specific torque or voltage constant. This flexibility allows the SlimTorq™ motors to be tailored to meet the precise requirements of virtually any application.
To learn more about the SlimTorq™ product range, please explore our product catalog and product selector.
Custom Frameless Motors
Thanks to the flexibility of the FiberPrinting™ process, Alva motors can be customized in many different ways, including dimensions, performance, mass, inertia, electrical specifications, and many others to meet specific customer requirements. This could include changes like a particular inner or outer diameter, axial length, target weight, or rotor inertia, and many more. Customization may also involve maximizing the motor constant within space or weight constraints, or tailoring the design to achieve a specific torque or voltage constant. These adjustments are typically achieved by modifying the width, length, and winding layout of the stator mats, as well as resizing the magnets.
In addition to a highly adaptable manufacturing process, Alva has developed a Rapid Design Tool capable of iterating 100,000 motor designs per hour. This enables rapid exploration of design alternatives to identify the optimal solution for each specific application.
Frameless Motor Specifications
Alva has a broad range of motor options and can help out evaluate thermal conditions and adapt winding configurations to suit the specific requirements of any project. For assistance in selecting the most suitable motor, please refer to our product catalog, product selector or contact us directly.
Frameless Motor Applications
Alva’s frameless, slotless motors are widely used in high-performance applications that demand a compact form factor, low cogging torque, and smooth, precise motion. Typical use cases include:
- Robotic joints
- Humanoids
- Surgical robots
- Exoskeletons
- Gimbals & stabilized platforms
- Metrology devices
- Semiconductor equipment
- Aerospace systems & actuators
- Marine thrusters
- Marine actuators
- Flywheels and gyroscopes
The slotless design does not have cogging torque and as such enhances efficiency, making these motors ideal for applications requiring high dynamic response and low noise operation. Additionally, the frameless configuration enables direct integration into the mechanical assembly, offering engineers greater design flexibility and improved overall system performance.
Frameless Motor FAQs
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Typically 6-8 weeks.
Typically 16-20 weeks from confirmed specifications to first prototype.
NTC Temperature sensor or Hall effect sensors.
-40 to 80 degrees celsius ambient temperature for standard motors. Extended temperature versions are possible as custom designs.
Yes, our motors are typically rated to 72v and we can derive the speed-torque curves for any specific voltage supply within that range.
Yes, we can help out with suggesting suitable motors to a set of application requirements. And if we can’t find a match, we can also offer to create a custom design to match the need.
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