A motor operated butterfly valve arrangement, at least one valve element of which is to be brought into a proper extreme position such that water leakage or the like does not occur within the pipe controlled by the valve element, without the necessity to improve dimensional or mounting accuracy of the components and without the need to lock the motor actuating the valve element. An elastically deformable elastic coupling member is provided in a coupling mechanism interconnecting the motor and the valve element. As soon as the valve element reaches the desired extreme position in contact with a stopper, the motor is rotated to deform the elastic coupling member and to improve the contact between the valve element and the stopper. The motor is stopped in the deformed state of the elastic coupling member.