Roll paper printer and method of opening and closing a roll paper printer cover

A roll paper printer comprising:

• a printhead that prints on paper supplied from a paper roll;
• a roll paper storage unit that is a compartment for accommodating roll paper, and can pivot from a first position to a second position on an axis of rotation that is parallel to the axis of rotation of the paper roll;
• a tension roller that can contact the roll paper;
• and
• a linkage mechanism that can move the tension roller from a third position to a fourth position, and after moving the tension roller on a straight first path from the third position, moves the tension roller on a curved second path to the fourth position;
• wherein the roll paper storage unit pivots from the first position to the second position while the tension roller moves along the second path, and
• the tension roller is positioned upstream from the printhead in the roll paper transportation direction and applies tension to the paper which is pulled from the paper roll when in the third position, and
• when in the fourth position, is positioned with at least part of the tension roller vertically above a horizontal plane that is tangential to the bottom of the paper roll, is positioned in front of the direction in which the paper roll moves as a result of the roll paper storage unit pivoting from the first position to the second position, and contacts the paper roll and pushes the paper roll in the direction opposite the direction in which the paper roll moves.