of the internal rotor 23 in addition in the first side wall 24 there are two connecting passages 45 in the form of grooves running in the peripheral direction these are indicated in fig2 c in the form of broken lines each of the locking pins 44 is loaded with a force in the direction of the first side cover 24 by a spring element 46 if the internal rotor 23 assumes a position relative to the external rotor 22 in which a locking pin 44 is opposite the associated connecting passage 45 in the axial direction then this pin is forced into the connecting passage 45 and the respective rotational angle limiting device 42 43 changes from an unlocked state into a locked state in this way the connecting passage 45 of the first rotational angle limiting device 42 is constructed such that the phase position of the internal rotor 23 relative to the external rotor 22 is limited when the first rotational angle limiting device 42 is locked to a region between a maximum retarded position and the locking position if the internal rotor 23 is located relative to the external rotor 22 in the locking position then the locking pin 44 of the first rotational angle limiting device 42 contacts a stop formed in the peripheral direction by the connecting passage 45 whereby further adjustment in the direction of more advanced control times is prevented analogously the connecting passage 45 of the second rotational angle limiting device 43 is designed such that for a locked section rotational angle limiting device 43 the phase.