Locking device

The opposing curved ends of two ratchet arms (1, 2) are provided with identical intermeshing teeth (3, 4) and are connected to each other via a head part (10). This head part is connected to each ratchet arm end via a pivot axis (15) located in a central position in this end of the arm. The two arms can be fixed in different angular positions relative to each other via a spring-loaded catch. Moving the catch into an end position causes it to become released from its locking position.