Air connections The connections for air inlet and outlet of the screwdriver and head stroke modules can be attached on either the right or the left. Robust housing The housing is a mono-block structure, and is made of high- stability aluminium. A special coating creates wear-free surfac- es both inside and out. Drive connectionand transducer The connections between the spin- dle modules are made with solid teeth. This ensures quick assembly together with sure, play-free power transmission, even in applications with both left and right rotation. End-position sensors Monitoring of the spindle stroke and the screwing depth allow reliable recognition of errors even before the assembly process is completed. The initiators are easily accessible and simple to adjust. In the case of the spindle, the head and screwdriver stroke modules workparallel to each other. This allows a very short, compact form. Drive, transducer and screwdriver stroke are fixed, and do not have to be moved when the spindle moves. This reduces the moving mass, which is the prerequisite for fast cycle times and low wear on the spindle and the positioning system. The precise, automatic screw feed works on the proven Weber principle.