A roll paper printer having a cover movable between an open and closed position with the printer having hooks on locking levers disposed to the cover to hold the cover in the locked position upon engaging pins located on the printer body side and having an opening lever to unlock the cover. The printer also includes a paper cutter device having a stationary knife which is attached to the cover and contact plate parts which extend from the stationary knife for contacting the front panel part on the printer body and having extension springs disposed in tension for pulling the stationary knife towards the back of the printer such that upon closing the cover the contact plate parts push the cover to the front of the printer. This causes the hooks of the locking levers to press from the back against the engagement pins to eliminate any play in the cover when in cover is in the locked position and to assist in opening the cover when the cover opening lever is operated.