A Case Study for Infusion Systems: Coreless Brush DC Motor Controls Nutrient Flow for Medical Feeding Pumps
Enteral feeding pumps are medical devices with a built-in tube used to deliver nutrients directly to the stomach of patients who are unable to safely consume food by mouth. The motor systems in these small, lightweight devices must also deliver sufficient torque to ensure continuous flow. The pumps also must be able to adjust flow rates — depending on the nutrition formula and patient needs — with accuracy and precision.
Recently, a European infusion system supplier developed an enteral feeding pump that needed a compact motion system that could:
- Deliver liquids of both low and high viscosity.
- Ensure a smooth, continuous flow without peaks.
- Generate speed across a wide range of flows.
- Provide a long lifetime.
Portescap engineers worked with the enteral pump supplier’s team to create a motion system consisting of the Athlonix 22N™ brushed DC motor, an F16 magnetic encoder and a K24 gearhead along with required mechanical customization. The 22 mm diameter motor weighs just 53 g and features neodymium magnets to deliver 15.7 mNm of continuous torque to achieve an exceptional high power density. The miniature motor does not require a laminated core. Instead, the motor’s windings create a self-supporting design within a small footprint. The coreless design without iron laminations offers many benefits to promote pump precision, such as:
- The ability to avoid peaks in flow rate.
- Very low torque ripple to ensure smooth flow even at low speeds.
- Reduced inertia and mass.
The system’s F16 magnetic encoder integrates Hall sensors for control accuracy — all in a compact package.
Mini Motors Designed for Efficiency and Long Life
Since the enteral feeding pump is portable, energy efficiency is critical to maintain a long battery life. The Athlonix motor features precious metal commutation with low generated friction to achieve operational motor efficiency up to 90 percent. The K24 spur gearhead adds to that efficiency thanks to driving low current consumption at the required output torques. In addition, the motion system provides a long operating lifetime, and the motor’s precious metal commutation satisfies low current requirements for continuous operation.
Today, the enteral feeding pump supports patient nourishment by providing precise fluid control with high reliability as a result of Portescap’s integrated motion system. The cost-effective motion package also allows the manufacturer to mass-produce pumps to satisfy the needs of home and hospital customers.
For more information about Athlonix DC motors, visit our product page.