Abstract: A roll-over protective system for motor vehicles, with roll-over bars arranged at the vehicle's seats, each one being accommodated in a support fixed to the vehicle, and in the normal condition being held by a holding device in a lower, descended position of rest, and able to be brought into a raised, supporting position by releasing of the holding device under sensor control, wherein each roll-over bar has two legs, each of them pivoted at a spacing in the transverse axis of the vehicle with one end in bearings in the support fixed to the vehicle and able to fold down toward each other with their free end, and being interlocked in the raised condition. In order to hinder a digging in of the roll-over bar in soft ground, at least one of the two legs of the bar has a flattening in the region of the free end.

Abstract: The invention is based on a known rollover protection system for motor vehicles with a rollover body that is held guided in a holder affixed to the vehicle, a drive under spring tension for sensor-controlled deployment of the rollover body from a resting position to a protective position, and a locking device for the rollover body when deployed in the protective position. In order to create a very simple, low-cost and yet highly effective locking device, i.e. a block against retraction of the roll bar after a deployment due to an accident, the invention provides a detent pawl arrangement articulated in a pivoting manner and affixed to the vehicle and under spring tension in the locking direction by a retaining spring, with two extensions extending at least across the width of the rollover body, that in the protective position of the rollover body can be pivoted into direct active contact with corresponding supports on the rollover body.