Connection unit

A connection unit comprising:

• a body having a substantially flat plate shape and peripheral edges;
• a plurality of magnets, at least one of which being disposed on each side of the peripheral edges of the body;
• and
• a plurality of electrode terminals, at least four of which being disposed on the each side of the peripheral edges of the body, wherein
• an outer surface of the each side of the body has a curved surface which curves in a thickness direction or a surface having a polygonal cross section,
• the electrode terminals are disposed along the curved surface or the surface having the polygonal cross section of the outer surface,
• the at least four electrode terminals disposed on the each side of the peripheral edges of the body comprise even number of positive electrode terminals which include same signal and even number of negative electrode terminals which include same signal,
• the positive electrode terminals are disposed line-symmetrical about a perpendicular line perpendicular to and crossing a center of the respective side of the peripheral edges of the body, and
• the negative electrode terminals are disposed line-symmetrical about the perpendicular line.

A connection unit comprising:

• a body having a substantially flat plate shape and peripheral edges;
• a plurality of magnets, at least one of which being disposed on each side of the peripheral edges of the body;
• and
• a plurality of electrode terminals, at least five of which being disposed on the each side of the peripheral edges of the body, wherein
• an outer surface of the each side of the body has a curved surface which curves in a thickness direction or a surface having a polygonal cross section,
• the electrode terminals are disposed along the curved surface or the surface having the polygonal cross section of the outer surface,
• the at least five electrode terminals disposed on the each side of the peripheral edges of the body comprise either:
• odd number of positive electrode terminals which include same signal and even number of negative electrode terminals which include same signal, one of the positive electrode terminals being disposed at a center of the respective side of the peripheral edges of the body, the rest of the positive electrode terminals being disposed line-symmetrical about a perpendicular line perpendicular to and crossing the center of the respective side of the body, and the negative electrode terminals being disposed line-symmetrical about the perpendicular line perpendicular to and crossing the center of the respective side of the body, or
• odd number of negative electrode terminals which include same signal and even number of positive electrode terminals which include same signal, one of the negative electrode terminals being disposed at a center of the respective side of the peripheral edges of the body, the rest of the negative electrode terminals being disposed line-symmetrical about the perpendicular line perpendicular to and crossing the center of the respective side of the body, and the positive electrode terminals being disposed line-symmetrical about the perpendicular line perpendicular to and crossing the center of the respective side of the body.