Electronic charging shelf system

A method of operating a cassette shelf mechanism, the method comprising:

• mounting a trolley equipped with rollers on a mounting plate to allow movement in an up- down direction;
• attaching a rotary hinge to the trolley, the rotary hinge including a lower part;
• connecting a pivot hinge to the rotary hinge, the pivot hinge including an upper part connected to a shelf plate;
• mounting an extension tensioning module on the mounting plate, the extension tensioning module including a cable connected to the trolley to facilitate movement in the up-down direction;
• operating a direction selection mechanism to bias a rotation of the shelf plate in a user-selected direction;
• and
• unfolding the shelf plate from a closed position to an open position by rotating the upper part of the rotary hinge relative to the lower part.