Anti-Pinch Protection

Anti-pinch protection, also called anti-trap, bounce-back, or obstacle detection, is a family of functions intended to reduce trapping or crushing risk when a powered vehicle closure moves.

Main applications

Windows and movable roof panels: a covered system may stop and reverse when it detects an obstruction. US FMVSS No. 118 and UNECE Regulation No. 21 define particular operating and protection requirements for power-operated windows, partitions, and roof panels; their scope and tests are not identical.
Powered shades: a motorized window or roof shade may have its own obstruction response. This is separate from the protection for the adjacent glass or roof panel.
Powered doors and tailgates: these may use drive-load estimation, edge sensors, or other obstacle sensors to stop or reverse motion. They are different closure systems, and FMVSS No. 118 does not extend its automatic-reversal requirements to power sliding doors or liftgates.

No universal mechanism

“Anti-pinch” describes the safety purpose, not one sensor, threshold, response, or worldwide standard. A system may infer extra resistance through the drive or use dedicated contact or non-contact sensors. Depending on the closure and implementation, detection may stop motion, reverse it, or permit only limited continued operation. Supplier material also separates the regulator drive, obstacle sensors, and control unit, showing why the feature cannot be treated as one universal component.

Protection has limits. Geometry, object size and stiffness, seal friction, ice, alignment, calibration, and override modes can affect the response. The feature is not proof that every obstruction will be detected, and it should never be tested with a hand, neck, animal, or other body part. Follow the vehicle manual for checks and resetting.

For the deeper treatment of windows and shades, see Power Windows, Anti-Trap Systems, and Sunshades.

Main applications

No universal mechanism

Sources