Rollbar protection system for motor vehicles

In order to achieve a locking of the extended roll-over bar (1) against retraction already at a small extension stroke, a downwardly extending locking pin (14) is attached to the lower end of the guide block (11), which can be brought into locking engagement with a spring-biased locking pawl (15) that is rotatably mounted in the cross member (5) by means of a bearing pin (6). On this bearing pin is furthermore a release lever (18) for reversing the extended roll-over bar (1) and a spring-biased holding pawl (16) that can be brought into operative connection with a holding bracket (17) attached to the cassette bottom (10) for releasably holding the roll-over bar against the force of pre-tensioned drive pressure springs in the rest position, rotatably mounted. This compact arrangement of the pawls and the lever requires little installation space in the cross member. In addition, the number of components can be reduced.