Print precision improvement over long print jobs

• US 9,946,962 B2
• Filed: 09/13/2016
• Issued: 04/17/2018
• Est. Priority Date: 09/13/2016
• Status: Active Grant

• Current Assignee: Hand Held Products Incorporated (Honeywell International Inc.)
• Original Assignee: Datamax-O'Neil Corporation (Honeywell International Inc.)
• Inventors: Wong, Chin Young, Yap, Yaw Horng, Chua, Ching Hong
• Primary Examiner(s): Nguyen, Allen H
• Application Number:
  US15/263,840
• Publication Number:
  US 20180075328A1
• Time in Patent Office: 581 Days
• Field of Search: 358 112
• CPC Class Codes: G06K 15/024 for printing on segmented surfaces, e.g. sticker sheets, label rolls
• CPC Class Codes: G06K 15/16 Means for paper feeding or form feeding
• CPC Class Codes: G06K 15/4065 Managing print media, e.g. determining available sheet sizes feeding means G06K15/16
• CPC Class Codes: H04N 1/00037 Detecting, i.e. determining the occurrence of a predetermined state H04N1/00031 takes precedence
• CPC Class Codes: H04N 1/00058 using a separate apparatus
• CPC Class Codes: H04N 1/00068 Calculating or estimating
• CPC Class Codes: H04N 1/00705 at a plurality of spaced apart locations, e.g. as a sheet is fed through the apparatus
• CPC Class Codes: H04N 1/00734 Optical detectors
• CPC Class Codes: H04N 1/00779 Adjusting settings, e.g. mode, feeding rate or type of paper

Abstract

A method and apparatus for printer compensation is disclosed. A label stop sensor (LSS) detects a time T(1) associated with an initial label position near the beginning of a print job. The label stop sensor detects a time T(L) associated with a label position that is L labels later in the print job. From at least the times T(1) and T(L) and a printer media feed rate a processor calculates a difference between the initial label position and the later label position. A start adjustment factor is compensated by the difference between the initial label position and the later label position to account for changes in print position between the first label and the later label.

Claims

1. A method of printer compensation, comprising:

using a sensor, detecting a time T(1) associated with a first label position;

using the sensor, detecting a time T(L) associated with a second label position that is L labels later in a print job;

from at least the times T(1) and T(L) and a media feed rate, calculating a difference between the first label position and the second label position; and

compensating an adjustment factor by the difference between the first label position and the second label position to account for changes in print position along a label travel path.

2. The method according to claim 1, where the calculating comprises converting times T(1) and T(L) to a distance.

3. The method according to claim 1, where the calculating comprises converting times T(1) and T(L) to a distance represented in printed dots in a feed direction.

4. The method according to claim 1, where detecting the value T(1) further comprises detecting a sequence of M values T(1) through T(M);

and

where detecting the value of T(L) further comprises detecting a sequence of M adjacent values about label L.

5. The method according to claim 4, further comprising averaging the values of T(1) through T(M) to produce TA(1);

and

averaging the values of the M adjacent values about label L to produce TA(L).

6. The method according to claim 5, where the calculating comprises from at least the times TA(1) and TA(L), and a feed rate, calculating a difference between the first label position and the second label position.

7. The method according to claim 4, further comprising:

converting the M values T(1) through T(M) to distances D(1) through D(M); and

converting the M adjacent values about label L to M distances D(L−

M) through D(L).

8. The method according to claim 4, further comprising averaging the values of D(1) through D(L) to produce DA(1);

and

averaging the values of the M adjacent values about label L to produce DA(L).

9. The method according to claim 5, where the calculating comprises using the distances DA(1) and DA(L) to calculate a difference between the first label position and the second label position.

10. A method of printer compensation, comprising:

using a sensor detecting a sequence of time values T(1) through T(M) associated with a first label position;

converting the M values T(1) through T(M) to distances D(1) through D(M);

using the sensor, detecting times T(L−

M) through T(L) associated with a M label positions that are approximately L labels later in the print job;

converting the M adjacent values about second label L to L distances D(L−

M) through D(L);

averaging the values of D(1) through D(M) to produce DA(1);

averaging the values of D(L−

M) through D(L) to produce DA(L);

from at least the distances DA(1) and DA(L), calculating a difference between the first label position and the second label position; and

compensating an adjustment factor by the difference between the first label position and the second label position to account for changes in print position along a label travel path.

11. The method according to claim 10, where the distances are represented in printed dots in a feed direction.

12. A label printer device, comprising:

a sensor that detects a transition between labels;

a processor that receives and interprets signals from the sensor;

a motor that advances a label medium through the printer;

the processor being programmed to;

use the sensor to detect a time T(1) associated with a first label position;

use the sensor to detect a time T(L) associated with a second label position that is L labels later in the print job;

from at least the times T(1) and T(L), and a printer feed rate, calculate a difference between the first label position and the second label position; and

compensate an adjustment factor by the difference between the first label position and the second label position to account for changes in print position along a label travel path.

13. A label printer device according to claim 12 where the transition comprises at least one of a space, black mark, hole, or optical element.

14. The apparatus according to claim 12, where the processor is programmed to convert times T(1) and T(L) to distances.

15. The apparatus according to claim 12, where the processor:

in detecting the value T(1) is further programmed to detect a sequence of M values T(1) through T(M); and

in detecting the value of T(L) is further programmed to detect a sequence of M adjacent values about label L.

16. The apparatus according to claim 15, where the processor is further programmed to:

average the values of T(1) through T(M) to produce TA(1);

average the values of the M adjacent values about label L to produce TA(L); and

calculate from at least the times TA(1) and TA(L), and a printer media feed rate a difference between the first label position and the second label position.

17. The apparatus according to claim 15, where the processor is programmed to:

convert the M values T(1) through T(M) to distances D(1) through D(M);

convert the M adjacent values about label L to M distances D(L−

M) through D(L);

average the values of D(1) through D(M) to produce DA(1); and

average the values of the M adjacent values about label L to produce DA(L).

18. The apparatus according to claim 12, where the processor is programmed to calculate a difference between the distances DA(1) and DA(L) to calculate a difference between the first label position and the second label position.

19. The apparatus according to claim 18, where the distances DA(1) and DA(L) are represented as a number of printed dots in a feed direction.

20. The apparatus according to claim 12, where the processor is programmed to carry out the compensating by adjusting a value of an adjustment factor.