Connection apparatus of circuit board

Claim 1

A connection apparatus of a circuit board comprising a first circuit board, and a second circuit board prepared for said first circuit board which is detachably mounted via a connector only to said first circuit board, wherein: said second circuit board can be mounted with respect to said first circuit board in a normal direction, or in a reverse direction opposite to said normal direction, and when the second circuit board is mounted with regard to the first circuit board along either said normal direction, or said reverse direction, said first and second circuit boards can be operated under normal conditions; provided that when said second circuit board is mounted with respect to said first circuit board along either the normal direction, or the reverse direction, substantially the same electric circuits are formed between said first circuit board and said second circuit board, wherein at least two connectors are positioned in parallel to each other on said first circuit board, and terminal pins having the same pin arrangement order are provided in a point symmetry with respect to a center point between said connectors as a base point, and wherein at least two connectors fitted to said two connectors provided on said first circuit board are provided on said second circuit board, and terminal pins having the same pin arrangement order are provided on the second circuit board in a point symmetry with respect to a center point between said two connectors as a base point.