1. Field of the Invention
The present invention relates to a printer for sequentially performing printing on a printing medium by a plurality of printer heads.
2. Description of Related Art
A printer is conventionally known which has a plurality of printer heads capable of printing different colors and sequentially prints a printing sheet by the printer heads.
Moreover, some of the above printers are respectively constituted so that disorder of a printed image due to meandering of a printing sheet is prevented. For example, JP10-35021A discloses that a resist mark is printed on the both margins of a printing sheet when the first color is printed, the meandering state of the printed resist mark is detected when each color is printed from the second color downward and thereby the meandering state of the printing sheet is detected to properly move the position of each printer head so that each color is printed at a proper position in accordance with the meandering state of the printing sheet.
However, in the case of the above prior art, when printing is performed on a printing sheet, detection of the position of a resist mark and operation of a moving distance of the position of each printer head are performed for each printing sheet. Therefore, the time required for printing of each printing sheet increases. When the number of sheets to be printed is large, there is a problem that the printing speed is extremely decreased.
The present invention is made to solve unsolved problems of the above conventional printer and its object is to provide a printer capable of improving the printing speed.