Medical Brakes: How the Right Combination Can Benefit Medical Applications

Every industry has unique needs when it comes to control and automation products. At KEB we have the resources and product catalog to create custom solutions that meets the specific requirements of each new project we take on. When an application came across our desk requiring brake integration into an industrial motor, we saw the potential for uses in a specific industry – medical applications.

KEB’s spring-set brakes and permanent magnet brakes have qualities that make them good candidates for use in medical devices and robots. Surgical booms, imaging machine, surgical robots, and hospital beds are all examples of the kinds of machines that need precise, safe braking. Depending the machine, the P1 permanent magnet brake might be the best choice, or a COMBISTOP Type 38 spring-set brake might be the right tool for the job.

P1 permanent magnet brakes for medical applications

Surgical robots and medical imaging machines require precise movements, and the brake’s ability to stop and hold is key. KEB P1 permanent magnet brakes are small in size, but they have excellent torque density. The brakes are made from neodymium rare-earth magnets – the strongest permanent magnets currently available.

The magnets give P1 brakes the best torque-diameter ratio. They are also designed to work in a wide range of temperatures, so even if the medical machine produces a large amount of heat the braking ability can be relied upon to work correctly.

Spring-applied brakes for power-off and power-reduced states

Spring-applied (or spring-set) brakes from KEB America provide fail-safe power-off braking. The brakes are released when power is applied. In applications where safety is critical, power-off brakes are the best solution. Spring-applied brakes can also be held in a released position in a power-reduced state, meaning less heat is being generated overall. The spring-applied brakes from KEB can be configured in a wide range of sizes and voltages, and special connectors are available. The brakes are also easy to adjust, so they have a longer lifetime than brakes with a set airgap.

Custom solutions for medical applications

Though KEB brakes can be applied to many applications without adjustment or alteration, here at our manufacturing facility in Minnesota we’re able to provide a unique customization solution for our customers. In medical applications there is frequently a need for machines that can operate in a small space with a high degree of stability. Integrating the brake with the motor saves space by putting both components in one package. Having a brake on the motor side of the system installation means less torque is needed to properly engage the brake. Less torque means a smaller brake can be used, further decreasing the size. The smaller brake, usually a spring-set brake, can be used as a safety brake at the motor. It has minimal backlash and is power-off, so during a power failure they breaks will safely lock into place. An optional hand-release can be used to release the brake if needed. 

Once the motor brings the arms or joints into the proper position they need to be held in place without straying. For additional stability we add a larger brake on the output side of the system. Typically a permanent magnet or power-on brake could be used for this, as the spring-set brake on the motor side would be able to take care of the safety functions. These kinds of brakes have no residual torque and no backlash so they work well for positioning and holding armatures and booms for surgical robots.

Finally, our manufacturing facility is ISO-9001 certified and we are capable of adhering to ISO-13485 for medical robotic applications. We have equipment on site to perform precision testing as needed, and we can burnish brakes or clutches to ensure the right torque is available on installation of the product.