Connecting structure

A connecting structure received in a main device for connecting an auxiliary apparatus, the main device comprising a bottom board and a sidewall substantially perpendicularly connected to the bottom board, the main device defining an opening on the sidewall, the connecting structure comprising:

• a retracting part formed on the bottom board and close to the sidewall;
• and
• a clamping part pivotablly mounted on the bottom board and pivotally connected to the retracting part;
• wherein the retracting part drives the clamping part to extend out of the main device via the opening defined on the sidewall for connecting the auxiliary apparatus when the auxiliary apparatus is mounted on the main device;
• the retracting part retracts the clamping part into the main device when the auxiliary apparatus is unmounted from the main device, the auxiliary apparatus comprises a pair of hooks formed on an outer sidewall of the auxiliary apparatus, and the clamping part engages with an engaging structure for connecting the auxiliary apparatus.