Thermal printer and paper recognition method

1. A thermal printer comprising:

a feeding mechanism which feeds one of thermal papers which include a double-sided thermal paper having thermosensitive layers formed on both sides thereof and a single-sided thermal paper having a thermosensitive layer formed on one side thereof;

a first thermal head which is so provided as to be brought into contact with a first side of the thermal paper fed by the feeding mechanism and is configured to print an image on the first side of the paper;

a second thermal head which is so provided as to be brought into contact with a second side of the thermal paper fed by the feeding mechanism and is configured to print an image on the second side of the paper;

a mark determination section which is configured to determine whether a mark has been printed on at least one of the first and second sides of the thermal paper; and

a controller which is configured to control print operation based on a determination result from the mark determination section, wherein

the controller is configured to control double-sided printing by the first and second thermal heads in the case where the mark determination section has determined that a mark has been printed on both the first and second sides of the thermal paper,

the controller is configured to control single-sided printing by the first thermal head in the case where the mark determination section has determined that a mark has been printed on the first side of the thermal paper and control single-sided printing by the second thermal head in the case where the mark determination section has determined that a mark has been printed on one of the second side of the thermal paper.

2. A thermal printer comprising:

a feeding mechanism which feeds one of thermal papers which include a double-sided thermal paper having thermosensitive layers formed on both sides thereof and a single-sided thermal paper having a thermosensitive layer formed on one side thereof;

a first thermal head which is so provided as to be brought into contact with a first side of the thermal paper fed by the feeding mechanism and is configured to print an image on the first side of the paper;

a second thermal head which is so provided as to be brought into contact with a second side of the thermal paper fed by the feeding mechanism and is configured to print an image on the second side of the paper;

a mark determination section which is configured to determine whether a mark has been printed on at least one of the first and second sides of the thermal paper;

a controller which is configured to control print operation based on a determination result from the mark determination section;

a first mark sensor which detects a mark printed on the first side of the thermal paper; and

a second mark sensor which detects a mark printed on the second side of the thermal paper, wherein

the mark determination section is configured to make determination based on detection signals from the first and second mark sensors.

3. The thermal printer according to claim 2 , comprising:

a mark print section which is configured to print the mark on both the first and second sides of the thermal paper using the first and second thermal heads, wherein

the first and second mark sensors are disposed on the downstream side in the paper feeding direction relative to the first and second thermal heads.

4. A thermal printer comprising:

a feeding mechanism which feeds one of thermal papers which include a double-sided thermal paper having thermosensitive layers formed on both sides thereof and a single-sided thermal paper having a thermosensitive layer formed on one side thereof;

a first thermal head which is so provided as to be brought into contact with a first side of the thermal paper fed by the feeding mechanism and is configured to print an image on the first side of the paper;

a second thermal head which is so provided as to be brought into contact with a second side of the thermal paper fed by the feeding mechanism and is configured to print an image on the second side of the paper;

a mark determination section which is configured to determine whether a mark has been printed on at least one of the first and second sides of the thermal paper;

a controller which is configured to control print operation based on a determination result from the mark determination section;

a first image buffer in which print data to be printed on the first side of the thermal paper by the first thermal head is rendered as raster image data and stored; and

a second image buffer in which print data to be printed on the second side of the thermal paper by the second thermal head is rendered as raster image data and stored wherein

the controller is configured to control double-sided print, in the case where the mark determination section has determined that a mark has been printed on both the first and second sides of the thermal paper, by rendering received print data as raster image data so as to store the rendered raster image data respectively in the first and second image buffers and outputting the raster image data stored in the image buffers to the corresponding first and second thermal heads.

5. The thermal printer according to claim 4 , wherein

the controller is configured to control single-sided print, in the case where the mark determination section has determined that a mark has been printed on one of the first and second sides of the thermal paper, by rendering received print data as raster image data so as to store the rendered raster image data in one of the first and second image buffers corresponding to the thermal head which is so provided as to be brought into contact with a side on which the mark has been determined to be printed and outputting the raster image data stored in one of the image buffers to the corresponding first or second thermal head.

6. A thermal printer comprising:

a feeding mechanism which feeds one of thermal papers which include a double-sided thermal paper having thermosensitive layers formed on both sides thereof and a single-sided thermal paper having a thermosensitive layer formed on one side thereof;

a first thermal head which is so provided as to be brought into contact with a first side of the thermal paper fed by the feeding mechanism and is configured to print an image on the first side of the paper;

a second thermal head which is so provided as to be brought into contact with a second side of the thermal paper fed by the feeding mechanism and is configured to print an image on the second side of the paper;

a mark determination section which is configured to determine whether a mark has been printed on at least one of the first and second sides of the thermal paper;

a controller which is configured to control print operation based on a determination result from the mark determination section; and

a mark print section which is configured to print the mark on the thermal paper using one of the first and second thermal heads, wherein

the mark determination section is configured to determine whether the mark print section has printed the mark on the thermal printer, and

the controller is configured to control double-sided printing by the first and second thermal heads in the case where the mark determination section determines that the mark has been printed

the controller is configured to control single-sided printing by one of the first and second printer heads in the case where the mark determination section has determined that the mark has not been printed.

7. A thermal printer comprising:

a feeding mechanism which feeds one of thermal papers which include a double-sided thermal paper having thermosensitive layers formed on both sides thereof and a single-sided thermal paper having a thermosensitive layer formed on one side thereof;

a first thermal head which is so provided as to be brought into contact with a first side of the thermal paper fed by the feeding mechanism and is configured to print an image on the first side of the paper;

a second thermal head which is so provided as to be brought into contact with a second side of the thermal paper fed by the feeding mechanism and is configured to print an image on the second side of the paper;

a mark determination section which is configured to determine whether a mark has been printed on at least one of the first and second sides of the thermal paper;

a controller which is configured to control print operation based on a determination result from the mark determination section;

a paper determination section which is configured to determine, when the first thermal head is used to print an image on the single-sided thermal paper, that the paper has been loaded properly based on the determination by the mark determination section that a mark has been printed on the first side while determine that the paper has not been loaded properly based on the determination by the mark determination section that a mark has not been printed on the first side.

8. A thermal printer comprising:

a feeding mechanism which feeds one of thermal papers which include a double-sided thermal paper having thermosensitive layers formed on both sides thereof and a single-sided thermal paper having a thermosensitive layer formed on one side thereof;

a first thermal head which is so provided as to be brought into contact with a first side of the thermal paper fed by the feeding mechanism and is configured to print an image on the first side of the paper;

a second thermal head which is so provided as to be brought into contact with a second side of the thermal paper fed by the feeding mechanism and is configured to print an image on the second side of the paper;

a mark determination section which is configured to determine whether a mark has been printed on at least one of the first and second sides of the thermal paper;

a controller which is configured to control print operation based on a determination result from the mark determination section; and

a paper determination section which is configured to determine, when the first and second thermal heads are used to print an image on the double-sided thermal paper, that the paper has been loaded properly based on the determination by the mark determination section that a mark has not been printed on the paper while determine that the paper has not been loaded properly based on the determination by the mark determination section that any mark has been printed on the paper.

9. A paper recognition method of a printer which includes: a feeding mechanism which feeds one of thermal papers which include a double-sided thermal paper having thermosensitive layers formed on both sides thereof and a single-sided thermal paper having a thermosensitive layer formed on one side thereof; a first thermal head which is so provided as to be brought into contact with a first side of the thermal paper fed by the feeding mechanism and is configured to print an image on the first side of the paper; and a second thermal head which is so provided as to be brought into contact with a second side of the thermal paper fed by the feeding mechanism and is configured to print an image on the second side of the paper,

the method comprising:

determining whether a mark has been printed at least one of the first and second sides of the thermal paper;

recognizing a paper type based on a result of the determination; and

driving the first and second thermal heads to print the mark on both the first and second sides of the thermal paper.

10. A paper recognition method of a printer which includes: a feeding mechanism which feeds one of thermal papers which include a double-sided thermal paper having thermosensitive layers formed on both sides thereof and a single-sided thermal paper having a thermosensitive layer formed on one side thereof; a first thermal head which is so provided as to be brought into contact with a first side of the thermal paper fed by the feeding mechanism and is configured to print an image on the first side of the paper; and a second thermal head which is so provided as to be brought into contact with a second side of the thermal paper fed by the feeding mechanism and is configured to print an image on the second side of the paper,

the method comprising:

determining whether a mark has been printed at least one of the first and second sides of the thermal paper; and

recognizing a paper type based on a result of the determination, wherein

in the case where the mark is determined to have been printed on both the first and second sides of the thermal paper, it is recognized that the double-sided thermal paper has been loaded, while in the case where the mark is determined to have been printed only on one of the first and second sides of the thermal paper, it is recognized that the single-sided thermal paper has been loaded.

11. A paper recognition method of a printer which includes: a feeding mechanism which feeds one of thermal papers which include a double-sided thermal paper having thermosensitive layers formed on both sides thereof and a single-sided thermal paper having a thermosensitive layer formed on one side thereof; a first thermal head which is so provided as to be brought into contact with a first side of the thermal paper fed by the feeding mechanism and is configured to print an image on the first side of the paper; and a second thermal head which is so provided as to be brought into contact with a second side of the thermal paper fed by the feeding mechanism and is configured to print an image on the second side of the paper,

the method comprising:

determining whether a mark has been printed at least one of the first and second sides of the thermal paper; and

recognizing a paper type based on a result of the determination, wherein

when the first thermal head is used to print an image on the single-sided thermal paper, it is recognized that the paper has been loaded properly if a mark has been printed on the first side, while it is recognized that the paper has not been loaded properly if a mark has not been printed on the first side.

12. A paper recognition method of a printer which includes: a feeding mechanism which feeds one of thermal papers which include a double-sided thermal paper having thermosensitive layers formed on both sides thereof and a single-sided thermal paper having a thermosensitive layer formed on one side thereof; a first thermal head which is so provided as to be brought into contact with a first side of the thermal paper fed by the feeding mechanism and is configured to print an image on the first side of the paper; and a second thermal head which is so provided as to be brought into contact with a second side of the thermal paper fed by the feeding mechanism and is configured to print an image on the second side of the paper,

the method comprising:

determining whether a mark has been printed at least one of the first and second sides of the thermal paper; and

recognizing a paper type based on a result of the determination, wherein

when the first and second thermal heads are used to print an image on the double-sided thermal paper, it is recognized that the paper has been loaded properly if a mark has not been printed on the paper, while it is recognized that the paper has not been loaded properly if any mark has been printed on the paper.