Device and method for safety belts

The invention relates to a device for a safety belt in a vehicle seat, comprising a first locking organ (2) arranged at the safety belt and means (9, 10, 14) for detecting whether the first locking organ (2) is fixed in a second locking organ (5) arranged for detachable fixing at the first locking organ (2). The invention is characterized in that said means (9, 10, 14) comprise transmitting organs (10a) for the transmission of a signal, a transponder (9) arranged for the reception of said signal and for the transmission of an answering signal comprising information which identifies said first locking organ (2), and receiving organs (10b) for the reception of said answering signal, with said transponder (9) being arranged in said first locking organ (2) and said transmitting and reception organs (10) being arranged in said second locking organ (5) or vice versa, and in that said means (9, 10, 14) are arranged to determine whether the first locking organ (2) is fixed in a predetermined second locking organ (5) which corresponds to the first locking organ (2). The invention also relates to a method for detecting whether the person in a vehicle is using a safety belt. By means of the invention, improved detection of whether a safety belt in a vehicle is fixed in a correct manner is obtained.