Surgical Screwdriver Torque Limiter With Rolling-Element Torque Control

The patent removes the elastomer O-ring from the torque limiter design entirely. Instead of using an elastic element that degrades under thermal stress, the invention employs a rigid structure with rolling elements that maintain consistent mechanical properties during sterilization and operation, thereby eliminating the source of torque variation.

The patent replaces the elastic mechanical system (O-ring based torque limiting) with a rolling element based mechanical system. The rolling elements transition between engaged and disengaged positions in response to torque thresholds, providing precise torque limiting without relying on materials whose properties change under thermal stress.

The patent introduces asymmetric features in the form of blocking elements positioned at specific locations in the recesses. These blocking elements allow free movement of rolling elements in the screwing direction while preventing movement in the unscrewing direction until a specific torque threshold is reached, enabling precise bidirectional torque control.

The patent applies different functional properties to different regions of the torque limiter. The recesses provide free movement zones, while strategically positioned blocking elements create restricted zones that engage only under specific torque conditions, allowing localized control of torque transmission characteristics.