MOTION SYSTEM APPLICATIONS Shown here is an exploded cutaway of a slotless motor from Portescap. Notice (in copper) the ironless rotor-coil windings. Also notice the brushes (on flat springs) mounted on the black motor endcap (the rightmost subcomponent in this illustration). Portescap sells this motor with either sleeve or ball bearings for the output shaft support.
Brush DC versus brushless DC motors in disposable tools Disposable medical hand tools are seeing increased use due to their cost and hygiene benefits. Engineers who design these tools usually specify brush DC or brushless DC motors. Here we compare these two options. By Clémence Muron Applications engineer | Portescap
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early step of surgical power tool engineering is to determine whether the design will be disposable or reusable. Recent component design and manufacturing advances have rendered many single-use power tool designs for complex surgery a cost-effective option. Nowhere is this more apparent (or significant) than with today’s brush DC and brushless DC (BLDC) motors both of which have lower price points and higher performance than in the past.
cost requirements are vastly different. Reusable tools must often last hundreds or even thousands of surgeries — so must integrate premium components. In contrast, the components in disposable tools only need to perform for one surgery — which necessitates that these components be available in high volumes and at a competitive price.
Reusable and disposable surgical tools often have equivalent motor-performance requirements. However, their design life and
Though they may be too costly for disposable power tools, BLDC motors offer top reliability — so are the most common motor type in
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BRUSHLESS DC MOTORS FOR REUSABLE TOOLS — BRUSH DC MOTORS FOR SINGLE-USE
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