Thermal printer and method for controlling the same

Patent metadata

Field	Value
Publication number	US-9975365-B2
Application number	US-201615384438-A
Country	US
Kind code	B2
Filing date	Dec 20, 2016
Priority date	Dec 25, 2015
Publication date	May 22, 2018
Grant date	May 22, 2018

Abstract

In accordance with an embodiment, a thermal printer comprises a first thermal head, a first sensor and a control section. The first thermal head prints a first mark on a first surface of an image receiving medium. The first sensor detects a printing density of the first mark. The control section determines whether or not the printing density of the first mark is in a predetermined range, and adjusts the printing density by the first thermal head in the predetermined range in response to determining that the printing density of the first mark is out of the predetermined range.

First claim

What is claimed is:

1. A thermal printer, comprising:
a first thermal head configured to print a first mark on a first surface of an image receiving medium;
a first sensor configured to detect a printing density of the first mark; and
a control section configured to determine whether or not the printing density of the first mark is in a predetermined density range, and adjust the printing density by the first thermal head within the predetermined range in response to determining that the printing density of the first mark is outside of the predetermined range, wherein the print density is adjusted at different times based on a detection that thermal paper is being exchanged.

2. The thermal printer according to claim 1 , wherein the control section adjusts a control signal for the first thermal head in order to thicken the printing density by the first thermal head in a case in which the printing density of the first mark is lower than an lower limit value of the predetermined density range, and adjusts the control signal in order to thin the printing density by the first thermal head in a case in which the printing density of the first mark is higher than an upper limit value of the predetermined density range.

3. The thermal printer according to claim 1 , further comprising:
a second thermal head configured to print a second mark on a second surface of the image receiving medium; and
a second sensor configured to detect a printing density of the second mark, wherein the control section further configured to determine whether or not the printing density of the second mark is within the predetermined density range, and adjust the printing density by the second thermal head within the predetermined density range in response to determining that the printing density of the second mark is outside of the predetermined density range.

4. The thermal printer according to claim 2 , further comprising:
a second thermal head configured to print a second mark on a second surface of the image receiving medium; and
a second sensor configured to detect a printing density of the second mark, wherein the control section further configured to determine whether or not the printing density of the second mark is in the predetermined density range, and adjust the printing density by the second thermal head within the predetermined density range in response to determining that the printing density of the second mark is outside of the predetermined density range.

5. The thermal printer according to claim 3 , wherein a position in a width direction at which the first mark is printed on the first surface of the image receiving medium does not face a position in the width direction at which the second mark is printed on the second surface.

6. The thermal printer according to claim 1 , wherein the first thermal head is configured to print a set of black dots with a predetermined size on the first surface of the image receiving medium.

7. The thermal printer according to claim 1 , wherein the first sensor comprises an optical sensor.

8. The thermal printer according to claim 1 , wherein the first sensor detects the printing density using a strobe signal.

9. The thermal printer according to claim 1 , wherein the control section comprises a central processing unit.

10. A method for thermal printing, comprising:
printing on a first surface of a paper with a thermal head;
detecting a printing density on the first surface of a paper; and
determining whether or not the detected printing density is within a predetermined density range, and adjusting the printing density by the thermal head within the predetermined density range in response to determining that the detected printing density is outside of the predetermined density range, wherein the print density is adjusted at different times based on a detection that thermal paper is being exchanged.

11. The method according to claim 10 , wherein adjusting the printing density comprises adjusting a control signal for the thermal head in order to thicken the printing density in a case in which the printing density of the first mark is lower than an lower limit value of the predetermined density range, or adjusting a control signal in order to thin the printing density by the thermal head in a case in which the printing density of the first mark is higher than an upper limit value of the predetermined density range.

12. The method according to claim 10 , further comprising:
printing a second mark on a second surface of the image receiving medium with a second thermal head;
detect a printing density of the second mark; and
determining whether or not the printing density of the second mark is within the predetermined density range, and adjusting the printing density by the second thermal head within the predetermined density range in response to determining that the printing density of the second mark is outside of the predetermined range.

13. The method according to claim 11 , further comprising:
printing a second mark on a second surface of the image receiving medium with a second thermal head;
detect a printing density of the second mark; and
determining whether or not the printing density of the second mark is within the predetermined density range, and adjusting the printing density by the second thermal head within the predetermined density range in response to determining that the printing density of the second mark is outside of the predetermined density range.

14. The method according to claim 12 , wherein a position in a width direction at which the first mark is printed on the first surface of the image receiving medium does not face a position in the width direction at which the second mark is printed on the second surface.

15. The method according to claim 10 , wherein printing comprises printing a set of black dots with a predetermined size on the first surface of the image receiving medium.

16. The method according to claim 10 , wherein detecting the printing density comprises using an optical sensor.

17. The method according to claim 10 , wherein detecting the printing density comprises using a strobe signal.

18. A thermal printer, comprising:
a first thermal head configured to print a first mark on a first surface of an image receiving medium;
a first sensor configured to detect a printing density of the first mark; and
a control section configured to determine whether or not the printing density of the first mark is in a predetermined density range, adjust the printing density according to characteristics of the image receiving medium, and adjust the printing density by the first thermal head within the predetermined density range in response to determining that the printing density of the first mark is outside of the predetermined density range.

19. The thermal printer according to claim 18 , wherein the control section adjusts a control signal for the first thermal head in order to thicken the printing density by the first thermal head in a case in which the printing density of the first mark is lower than an lower limit value of the predetermined density range, and adjusts the control signal in order to thin the printing density by the first thermal head in a case in which the printing density of the first mark is higher than an upper limit value of the predetermined density range.

20. The thermal printer according to claim 18 , further comprising:
a second thermal head configured to print a second mark on a second surface of the image receiving medium; and
a second se

Assignees

• Toshiba Tec Kk

Inventors

• Hwa Lee Men
• Shiraishi Norihisa

Classifications

• B41J29/393 Primary

  Devices for controlling or analysing the entire machine {; Controlling or analysing mechanical parameters involving printing of test patterns} · CPC title

• B41J2/362

  Correcting density variation · CPC title

• B41J2/32

  using thermal heads · CPC title

• B41J2/36 Primary

  Print density control · CPC title

• B41J3/4075

  Tape printers; Label printers · CPC title