Patent ID: 6871663

Claim:
A pneumatic, reciprocating rotary driving mechanism unit for operating a shut-off member in a shut-off valve, comprising a substantially closed housing, in which a drive shaft is journalled which can be connected to said shut-off member, a pneumatic control valve for controlling said drive shaft and first signal transmitting means for delivering control signals to said pneumatic control valve, characterized in that the housing includes a base part, in which the drive shaft and the pneumatic control valve are present, and a first function part, in which the first signal transmitting means are present, which first function part is detachably and exchangeably connected to said base part so as to make it possible to exchange said first function part for a second function part containing second signal transmitting means of a type different from the first signal transmitting means, which first function part is exchanged for the second function part for the purpose of changing the manner in which the drive shaft can be controlled.