An open/close mechanism of a media feed path for feeding a sheet medium from a media insertion unit allowing for a reduced parts count and minimal installation space is disclosed. In an embodiment, an open/close lever and paper pressure member of a check feeding device pivot horizontally on first and second vertical support shafts. When the pressure member pivots and presses against the delivery roller, the back end of the lever is pushed by the pressure member, pivoting the lever thereby retracting the front end of the lever from the check feed path. Because the lever is urged in a pivot direction causing the front end to enter the check feed path, when the paper pressure member returns to the position not pressed against the delivery roller, the open/close lever pivots in this urging direction returning to the position where the front end closes the check feed path.