Data transfer switch

A data transfer switch, comprising:

• a casing including a front casing part, a rear casing part and a side wall interconnecting the front and rear casing parts;
• a linking unit rotatably provided inside said casing and including a plurality of interconnected linking pieces, each of said linking pieces being a relatively thin cylindrical insulator and having one side provided with an axial tubular projection which extends toward an adjacent one of said linking pieces so as to form an annular groove between each of said linking pieces and the adjacent one of said linking pieces;
• a plurality of connector pin sets mounted on said side wall of said casing, each of said connector pin sets having a plurality of connector pins which respectively extend into a corresponding said annular groove of said linking unit;
• and
• a conductive pattern provided on each of said linking pieces at each said annular groove, rotation of said linking unit from a first angular position to a second angular position causing said conductive pattern to break electrical connection between a first one of said connector pins sets and a second one of said connector pin sets and make electrical connection between the first one of said connector pin sets and a third one of said connector pin sets.