Patent attributes
A printer has a main body and a printer unit that is fixed to the main body. The printer unit has an upper cover and a lower cover. The lower cover is attached to the main body and the upper cover is fixed to the lower cover. A hollow space is formed between the upper and lower covers and a printing paper is set in this space. A sensor is provided in the upper cover and it detects a mark on the non-printable surface of the printing paper. One protrusion is provided in each of the upper and lower covers such that the protrusions make an electrical contact when the upper and lower covers are closed. A control unit is provided in the main body and it is electrically connected to the mark detection unit through the protrusions on the upper and lower covers and it controls various operations of the printer.
