One-Way Bearings (Sprag / Roller Ramp)
Characteristics: Asymmetric profile; inner and outer ramps; spring energized.
Advantages: Instantaneous engagement (<1°) vs. standard needle type (2-3°). Lifetime 10^7 overrunning cycles in helicopter rotors or industrial freewheels. Static torque capacity 3X standard.
Technical Ceiling: Max overrunning speed 6000 rpm (roller type 10,000 rpm); torque capacity up to 2000 Nm in 100 mm OD; indexing frequency 50 Hz.
Caution: Standard bearings cannot replace one-way function - they allow backdriving. Must orient correctly (CW or CCW locking). Dust contamination kills engagement; standard seals are insufficient - use double lip.
One-Way Bearings, also known as sprag clutches, one-way clutches, or overrunning clutches, are specialized bearings that transmit torque in one rotational direction while allowing free rotation (overrunning) in the opposite direction. These bearings provide automatic engagement and disengagement without external control mechanisms.
