Brushless DC (BLDC) motors are essential components in many medical tools and types of equipment because they offer exceptional torque, speed, and energy efficiency in compact designs. As medical tools become smaller, faster, and more precise, the need for advanced brushless motors continues to grow.
BLDC motors are used in everything from surgical drills to robotic systems. They have several significant benefits, including quiet operation, low maintenance, and precise control. These attributes make them well-suited for sensitive environments where patient safety, hygiene, and accuracy are top priorities. Here we’ll look at the advantages of BLDC motors for medical applications and outline some best practices for designing BLDC motors.
The Importance of Design Consideration in Brushless Motors for Medical Devices
Technology transforms healthcare, and brushless DC motors have been a big part of the changes. Medical-grade BLDC motors power essential devices, from dental drills to imaging system equipment to pumps and ventilators, and in these applications, precision, reliability, and hygiene are critical.
Unlike brushed motors, BLDC motors generate less heat, create minimal electromagnetic interference, and accumulate less wear and tear from friction-producing brushes. This makes them well-suited to sensitive applications around patients and multiple other monitors and electronic devices.
Some specific advantages of medical BLDC motors include:
- Long service life with minimal maintenance.
- Excellent speed and position control.
- High efficiency and torque at various loads.
- Compact, lightweight design.
- Quiet operation and low vibration.
- Arcless operation for lower contamination risk.
BLDC Motor Design Best Practices for Medical Applications
There are a number of factors beyond power requirements to balance in BLDC motor design. Things like torque load, speed, noise, motion control needs, and environmental conditions impact the materials and configuration of the motor for optimal performance. It’s important for all of these considerations to be discussed early in the design process to ensure no critical functionality is overlooked.
Here are some best practices:
- Autoclavability. In order for medical devices to be sterilized, it is critical that all components, including brushless DC motors are able to withstand the steam sterilization process. This type of process subjects components to high heat (138C) and moisture that can damage critical components if they are not properly protected.
- Understand Torque and Load Requirements. Motors are subject to a few types of loading during operation, and it’s important to design a motor that can withstand these loads. Torque load is the force applied to the motor shaft to cause it to rotate, so it can create motion or power a device. Axial load is force parallel to the axis of the shaft, usually pushing or pulling. Radial load is force perpendicular to the shaft. Anticipating axial and radial loads helps prevent damage to bearings or the motor shaft, which can cause wear, damage, or failure.
- Model the Motion Cycle. Knowing the torque and speed demands throughout the duty cycle is important for identifying peak and continuous load patterns. Understanding these makes it easier to select materials and components to avoid overheating or damage.
- Prioritize Thermal Management and Durability. Medical motors often operate for long periods without interruption. Effective heat dissipation, especially in compact housings, allows the motor to run efficiently without generating excessive heat that could melt or damage surrounding components or the motor itself. Static windings are often selected because they have excellent thermal performance and higher overload capabilities.
- Design for Compactness and Quiet Operation. Medical applications often require equipment, tools, and devices that are small, quiet, and unobtrusive. BLDC motors can be designed to meet these requirements through proper material and magnetic circuit choice.
- Aim for High Power Density and Speed. Instruments such as surgical or dental tools accelerate rapidly and must have reliable, consistent power at high speeds. BLDC motors are preferred for these applications due to their lightweight and high-speed nature.
Brushless Motor Design for Medical BLDC Motors by CMI
Brushless DC motors offer several key advantages in medical settings, making them a common choice for many types of tools, machines, and equipment used for patient care. Composite Motors (CMI) offers significant advantages to the medical device industry due to our proprietary design and manufacturing capabilities to meet autoclavability requirements. With our custom, USA-made BLDC motors designed for these specialized applications, our engineering team supports clients through every stage of development through commercialization.
Visit our website to learn more about our medical and veterinary solutions and read detailed application data sheets and case studies, or contact us today to start your custom motor design.