JP4406619B2 - Printer and recording medium conveyance position deviation detection method in printer - Google Patents

Description

  The present invention relates to a printer and a recording medium conveyance position deviation detection method in the printer, and more particularly to a printer that conveys a recording medium by conveyance means provided corresponding to a plurality of recording units and a recording medium conveyance position deviation in the printer. It relates to a detection method.

  2. Description of the Related Art Conventionally, in a printer that performs recording using a plurality of ink ribbons to which inks of different colors are applied, each ink ribbon is provided by a plurality of recording units each having a recording head provided corresponding to each ink ribbon. A printer is known that records a desired image on a recording medium by transferring each of the inks onto the recording medium.

  In such a printer, a plurality of recording units are provided so as to be arranged in parallel at a predetermined interval along the conveyance path of the recording medium. Each recording unit includes an ink ribbon, a recording head, and an ink ribbon. And a platen roller provided so as to face the recording head. Each ink ribbon is coated with yellow (Y), magenta (M), cyan (C), and black (BK) ink from the most upstream recording unit in the recording medium conveyance direction.

  Further, in the printer, a transport unit corresponding to each recording unit is provided along a transport path in the vicinity of each recording unit, and each transport unit is provided to face each other with a recording medium interposed therebetween. It has a pair of conveyance rollers.

  In such a printer, the recording medium is sandwiched between the conveyance rollers, and the recording medium is conveyed by rotating the conveyance rollers, and the recording head and the platen roller are sequentially recorded on the upstream side in the conveyance direction of the recording medium. A desired color image is recorded by transferring the ink to the recording medium while being pressed against the medium (for example, Patent Document 1).

  However, in the conventional printer as described above, since the recording medium is transported by a plurality of transport units, the position where each transport roller is arranged is different in each transport unit, When the recording medium is transported at different angles in the transport direction in each transport unit, the recording medium is meandered and transported, which may cause a shift in the transport position. If the recording of the image is continued in a state where the transport position of the recording medium is deviated, the position of the image recording in each recording unit may be deviated, and good image recording may not be performed. Had a problem.

JP 2003-231318 A

  The present invention has been made in view of these points. A printer and a recording medium in the printer that can prevent the recording position of the image from being shifted by detecting a shift in the transport position of the recording medium. It is an object of the present invention to provide a method for detecting a transfer position deviation.

  In order to achieve the above object, the printer according to the present invention is characterized in that a plurality of recording units are provided in parallel along a recording medium conveyance path, and record images on the recording medium. A first recording unit that is disposed on the most upstream side in the conveyance direction of the recording medium and records a marker having a predetermined width dimension on the recording medium, and is provided corresponding to each recording unit, and the recording medium A plurality of conveying means for conveying the recording medium, a detecting means corresponding to each recording unit, provided opposite to the recording medium, for detecting a leading edge and a trailing edge of the marker, and detected by each detecting means. The front edge and the rear edge calculate a width dimension when the marker is transported to a position facing each of the detection means, and the calculation is performed before calculating the width dimension and the width dimension. The average width dimension of the marker is calculated according to the width dimension of the marker, the difference between the width dimension and the average width dimension is calculated, and the standard deviation of the marker width dimension is calculated based on the difference. And a control unit that compares the difference with a predetermined multiple of the standard deviation and determines that a conveyance deviation has occurred when the difference exceeds a predetermined multiple of the standard deviation.

  According to the printer of the present invention, after calculating the width dimension of the marker when the portion of the recording medium where the marker is recorded is conveyed at a position facing each sensor, the average value of the width dimension and the calculated width dimension are calculated. By calculating the standard deviation based on the difference between the two and the difference between the difference and a predetermined multiple of the standard deviation, it is possible to easily detect that a deviation has occurred in the recording medium conveyance position in the printer.

  In addition, another feature of the printer according to the present invention is that each of the conveyance units is a conveyance roller, and each of the conveyance rollers is driven by a stepping motor, and the control unit includes the detection unit. Thus, the width dimension of the marker is calculated based on the number of driving steps when the leading edge is detected and the number of driving steps when the trailing edge is detected.

  According to another printer of the present invention, the width dimension of the marker when it is transported to a position facing each sensor can be represented by the number of driving steps of the transport roller. It can be easily calculated.

  Further, the marker is a positioning marker which is recorded in the vicinity of the recording start position of the image on the recording medium and serves as a reference when recording the image on each recording head.

  According to the other printer of the present invention, it is possible to detect a shift in the transport position of the recording medium by using the positioning marker that functions as a reference when starting the image recording in each recording head. Further, there is no need to record other markers, and a shift in the transport position of the recording medium can be detected more easily.

  The recording medium conveyance position deviation detection method in the printer according to the present invention is characterized in that an image is recorded on the recording medium by a plurality of recording units provided in parallel along the recording medium conveyance path, and A marker having a predetermined width dimension is recorded on the recording medium by a first recording unit arranged on the most upstream side in the conveyance direction of the recording medium among the recording units, and provided corresponding to the recording units. A method of detecting a conveyance position deviation of the recording medium in a printer that conveys the recording medium by a plurality of conveying means, the detection means corresponding to each recording unit and provided facing the recording medium, The leading edge and the trailing edge are detected, and the leading edge and the trailing edge convey the position where the marker faces each detection means. And calculating the average width dimension of the marker based on the width dimension and the width dimension of the marker calculated before calculating the width dimension, and calculating the width dimension and the average width dimension. And calculating a standard deviation of the width dimension of the marker based on the difference, comparing the difference with a predetermined multiple of the standard deviation, and the difference exceeds a predetermined multiple of the standard deviation. In this case, it is determined that a conveyance deviation has occurred.

  According to the recording medium conveyance position deviation detection method in the printer according to the present invention, after calculating the width dimension of the marker when the portion of the recording medium on which the marker is recorded is conveyed at a position facing each sensor, The standard deviation is calculated from the difference between the average value of the width dimension and the calculated width dimension, and by comparing the difference with a predetermined multiple of the standard deviation, a deviation occurs in the transport position of the recording medium in the printer. This can be easily detected.

  As described above, according to the printer and the recording medium conveyance position deviation detection method in the printer according to the present invention, it is possible to easily detect the conveyance position deviation of the recording medium, and thereby to the image recording position. Can be reliably prevented from occurring.

  Hereinafter, an embodiment of a printer according to the present invention will be described with reference to FIGS.

  As shown in FIGS. 1 and 2, the printer 1 according to this embodiment includes a paper feed roll 4 around which a long recording medium 2 is wound.

  The recording medium 2 is conveyed along a predetermined conveyance path 4 while being guided by a plurality of guide rollers 3, and an image having a predetermined size is recorded on the recording medium 2.

  The printer 1 has a plurality (four in the present embodiment) of recording units 5 (5a, 5b, 5c, 5d) provided so as to be spaced apart at a predetermined interval along the transport path 4. Each recording unit 5 is a first recording unit 5a, a second recording unit 5b, a third recording unit 5c, and a fourth recording unit 5d from the most upstream side in the conveyance direction of the recording medium 2.

  Each recording unit 5 has an ink ribbon 6 to which inks of colors Y, M, C, and BK are applied in order from the most upstream side in the conveyance direction of the recording medium 2. Each of them is wound around a pair of ink ribbon rolls 7 and guided by a ribbon guide roller 8 so that the ink application surface is conveyed opposite to the recording medium 2.

  Each recording unit 5 is provided with a recording head 10 composed of a thermal head formed with a length corresponding to the width dimension of the recording medium 2 at a position facing the recording medium 2 via the ink ribbon 6. At a position facing the ink ribbon 6 in the recording head 10, a plurality of heating elements facing the width dimension of the recording medium 2 are arranged in parallel in a line.

  Each recording head 10 heats a desired heating element based on the recording data input to the printer 1 to transfer the ink on the ink ribbon 6 to the recording medium 2, and the recording of the first recording unit 5a. As shown in FIGS. 3A and 3B, the head 10 transfers the Y ink to a predetermined portion in the vicinity of the image recording start position on the recording medium 2, and a positioning marker 11 having a predetermined width dimension. Is to be recorded. The positioning marker 11 functions as a reference when starting image recording in each recording head 10.

  Further, each recording unit 5 is provided with a platen roller 12 formed with a length corresponding to the width dimension of the recording medium 2 at a position facing the recording head 10 via the ink ribbon 6 and the recording medium 2. ing.

  In the vicinity of each recording unit 5, sensors 14 (14 a, 14 b, 14 c, 14 d) as detection means for detecting the positioning marker 11 recorded on the recording medium 2 with Y ink are respectively provided in each recording unit 5. The first sensor 14a, the second sensor 14b, the third sensor 14c, and the fourth sensor 14d are arranged from the most upstream side in the conveyance direction of the recording medium 2. Each sensor 14 detects the leading edge 11a and the trailing edge 11b of the positioning marker 11.

  The printer 1 has a plurality of transport units 16 (16a, 16b, 16c, 16d) corresponding to the respective recording units 5 as transport means, and each transport unit 16 is the most upstream in the transport direction of the recording medium 2. From the side, the first transfer unit 16a, the second transfer unit 16b, the third transfer unit 16c, and the fourth transfer unit 16d are provided.

  Each transport unit 16 is disposed in the vicinity of the transport path 4 and on the downstream side of each recording unit 5 in the transport direction. The transport units 16 face each other via the recording medium 2 and perform recording. A pair of conveying rollers 17A and 17B are provided so as to sandwich the medium 2 from both sides. One of the transport rollers 17 </ b> A and 17 </ b> B is rotated by a stepping motor 19. Each transport unit 16 sandwiches the recording medium 2 from both surfaces by both transport rollers 17A and 17B, and transports the recording medium 2 in a predetermined transport direction by rotational driving of one transport roller 17A.

  A cutting blade 21 is provided in the vicinity of the conveyance path 4 of the recording medium 2 and downstream of the recording heads 10 in the conveyance direction. The cutting blade 21 is a long recording medium on which recording has been completed. 2 is cut into a predetermined length.

  The printer 1 includes a control unit 23 that controls the operation of each unit of the printer 1, and the control unit 23 includes a drive unit 24 that drives each recording unit 5, each conveyance unit 16, each sensor 14, and the like. ing.

  The control unit 23 includes a width calculation unit 25 that calculates the width dimension of the positioning marker 11 when the positioning marker 11 is conveyed to a position facing each sensor 14. In this embodiment, when the front end edge 11a and the rear end edge 11b of the positioning marker 11 are detected by each sensor 14, the width calculating unit 25 drives the transport roller 17A when the front end edge 11a is transported. The number of drive steps when the rear edge 11b is being conveyed is acquired from the stepping motor, and the width dimension of the positioning marker 11 is calculated based on the difference between the two drive steps.

  The controller 23 has an average width calculator 26 that calculates the average of the width dimensions of the plurality of positioning markers 11 that have already been calculated. In the present embodiment, the average width calculation unit 26 uses the width dimension of the positioning marker 11 when detected by the first sensor 14a as a reference width dimension, and the average width calculation unit 26 detects when the second sensor 14b detects the average width. When the width dimension (second width dimension) of the positioning marker 11 is calculated, an average width dimension that is an average of the width dimensions is calculated based on the second width dimension and the reference width dimension. The average value calculator 26 calculates the reference width dimension and the second width when the width calculator 25 calculates the width dimension (third width dimension) of the positioning marker 11 as detected by the third sensor 14c. The average width dimension of the dimension and the third width dimension is calculated. Further, when the width calculation unit 26 calculates the width dimension of the positioning marker 11 detected by the fourth sensor 14d by the width calculation unit 25, the average width calculation unit 26 calculates the reference width dimension, the second width dimension, and the third width dimension. The average width dimension of the fourth width dimension is calculated.

  The control unit 23 includes a difference calculation unit 27 that calculates the difference between the width dimension of the positioning marker 11 calculated by the width calculation unit 25 and the average width dimension, and the difference calculated by the difference calculation unit 27. And a standard deviation calculation unit 28 for calculating the standard deviation of the width dimension.

  Further, the control unit 23 compares the difference calculated by the difference calculation unit 27 with a predetermined multiple of the standard deviation calculated by the standard deviation calculation unit 28, and when the difference exceeds a predetermined multiple of the standard deviation. The comparison / determination unit 29 determines that a conveyance deviation has occurred. In the present embodiment, the comparison / determination unit 29 determines that a conveyance deviation has occurred when the difference exceeds three times the standard deviation. When the comparison / determination unit 29 determines that a conveyance deviation has occurred, the comparison / determination unit 29 outputs conveyance deviation data to the driving unit 24. When the driving unit 24 inputs the conveyance deviation data, each stepping step is output. The drive of the motor 19 is stopped.

  Next, a method for detecting a conveyance position deviation of the recording medium 2 in the printer 1 according to the present embodiment will be described.

  First, when recording data of one image such as a desired character or figure is input to the printer 1, the drive unit 24 of the printer 1 drives the conveyance roller 17 </ b> A of each conveyance unit 16 by the stepping motor 19 to record. The medium 2 is transported in a predetermined transport direction.

  Subsequently, in the first recording unit 5a, the driving unit 24 press-contacts the recording head 10 and the platen roller 12 via the recording medium 2 and the Y ink ribbon 6 to heat a predetermined heating element of the recording head 10. Then, the positioning marker 11 is recorded by transferring Y ink in the vicinity of the recording start position of one image on the recording medium 2 (ST1).

  Further, when the leading edge 11a of the positioning marker 11 is detected by the first sensor 14a, the driving unit 24 transfers Y ink to the recording medium 2 by the recording head 10 of the first recording unit 5a based on the recording data. At the same time, the width calculator 25 starts monitoring the number of drive steps of the transport roller 17A. When the rear end edge 11b of the positioning marker 11 is detected by the first sensor 14a, as shown in FIG. 3A, the width calculation unit 25 detects the positioning marker 11 detected by the first sensor 14a. The reference width dimension x is calculated based on the number of driving steps of the conveying roller 17A from the leading edge 11a to the trailing edge 11b (ST2). In this embodiment, the marker width dimension including the reference width dimension is represented by the number of drive steps.

  Next, when the leading edge 11a of the positioning marker 11 is detected by the second sensor 14b, the driving unit 24 transfers M ink to the recording medium 2 by the recording head 10 of the second recording unit 5b. Subsequently, when the rear end edge 11b of the positioning marker 11 is detected by the second sensor 14b, the width calculator 25 detects the rear end edge 11b from the front end edge 11a of the positioning marker 11 detected by the second sensor 14b. The second width dimension Y is calculated based on the number of driving steps of the conveying roller 17A up to (ST3).

  The width calculation unit 25 outputs the data of the reference width dimension X and the second width dimension Y to the average calculation unit 26, and the average calculation unit 26 calculates the average width dimension based on the reference width dimension X and the second width dimension Y. (ST4).

  The average calculator 26 outputs the data of the average width dimension and the second width dimension to the difference calculator 27, and the difference calculator 27 calculates the difference between the average width dimension and the second width dimension (ST5).

  The difference calculator 27 outputs the difference data to the standard deviation calculator 28, and the standard deviation calculator 28 calculates the standard deviation based on the difference (ST6).

  The standard deviation calculation unit 28 outputs the standard deviation and difference data to the comparison / determination unit 29, and the comparison / determination unit 29 determines whether or not the difference value exceeds three times the standard deviation (ST7).

  If the difference value exceeds three times the standard deviation (Yes in ST7), the comparison / determination unit 29 determines that the conveyance position is deviated and sends the conveyance position deviation data to the drive unit 24. The drive unit 24 stops driving the stepping motor 19 (ST8). Thereby, the conveyance of the recording medium 2 is stopped. On the other hand, if the difference value does not exceed three times the standard deviation (No in ST7), it is determined whether the image recording in each recording head 10 is completed (ST9).

  If it is determined that the image recording in each recording head 10 has not been completed (No in ST9), then the width calculation unit 25 is arranged on the downstream side of the recording medium 2 in the transport direction. Wait until the positioning marker 11 is detected by the (third sensor 14c, the fourth sensor 14d).

  Next, when the leading edge 11a of the positioning marker 11 is detected by the third sensor 14c, the driving unit 24 transfers the C ink to the recording medium 2 by the recording head 10 of the third recording unit 5c. Subsequently, when the rear end edge 11b of the positioning marker 11 is detected by the third sensor 14c, the width calculation unit 25 detects the rear end edge 11b from the front end edge 11a of the positioning marker 11 detected by the third sensor 14c. The third width dimension is calculated based on the number of driving steps of the conveying roller 17A up to (ST3). The average calculation unit 26 calculates the average width dimension based on the reference width dimension X, the second width dimension Y, and the third width dimension (ST4), and the difference calculation unit 27 calculates the difference between the average width dimension and the third width dimension. Is calculated (ST5). Further, the standard deviation calculation unit 28 calculates the standard deviation based on the difference (ST6), and the comparison / determination unit 29 determines that the difference is greater than three times the standard deviation (Yes in ST7). 24, the transfer position deviation data is output. On the other hand, if the value of the difference exceeds three times the standard deviation (No in ST7) and if it is determined that the image recording in each recording head 10 has not been completed (No in ST9), then The width calculation unit 25 waits until the positioning marker 11 is detected by the fourth sensor 14d.

  Subsequently, when the leading edge 11a of the positioning marker 11 is detected by the fourth sensor 14d, the drive unit 24 transfers the BK ink to the recording medium 2 by the recording head 10 of the fourth recording unit 5d. Subsequently, when the rear end edge 11b of the positioning marker 11 is detected by the fourth sensor 14d, the width calculation unit 25 detects the rear end edge 11b from the front end edge 11a of the positioning marker 11 detected by the fourth sensor 14d. The fourth width dimension is calculated based on the number of driving steps of the conveying roller 17A up to (ST3). The average calculation unit 26 calculates the average width dimension based on the reference width dimension X, the second width dimension Y, the third width dimension, and the fourth width dimension (ST4), and the difference calculation unit 27 calculates the average width dimension and the fourth width dimension. The difference from the width dimension is calculated (ST5). Further, the standard deviation calculation unit 28 calculates the standard deviation based on the difference (ST6), and the comparison / determination unit 29 determines that the difference is greater than three times the standard deviation (Yes in ST7). 24, the transfer position deviation data is output. On the other hand, if the value of the difference exceeds three times the standard deviation (No in ST7), all the images in each recording head 10 including the recording of the next image to be recorded next is recorded. When it is determined that the recording of the recording medium 2 has been completed (Yes in ST9), the detection of the conveyance position deviation of the recording medium 2 is terminated.

  According to the present embodiment, after calculating the width dimension of the positioning marker 11 when the portion of the recording medium 2 on which the positioning marker 11 is recorded is transported to the position facing each sensor 14, the average of the width dimension is calculated. By calculating the standard deviation based on the difference between the value and the calculated width dimension, and comparing the difference with a predetermined multiple of the standard deviation, it is confirmed that the transport position of the recording medium 2 in the printer 1 has shifted. It can be easily detected.

  Therefore, by detecting the conveyance position deviation of the recording medium 2, it is possible to reliably prevent the deviation of the image recording position.

  Further, the width dimension of the positioning marker 11 can be calculated more easily by representing the width dimension of the positioning marker 11 when transported to a position facing each sensor 14 by the number of driving steps of the transport roller 17A. Can do.

  Further, since the positioning marker 11 that functions as a reference when starting recording of an image in each recording head 10 can be used to detect a shift in the transport position of the recording medium 2, other markers 11 are recorded. Therefore, it is possible to more easily detect the deviation of the transport position of the recording medium 2.

  In addition, this invention is not limited to the said embodiment, A various change is possible as needed.

  For example, in this embodiment, when the deviation of the conveyance position is detected, the conveyance of the recording medium 2 is stopped by stopping the driving of the stepping motor 19 for driving the conveyance roller 17A. However, it is not limited to this. For example, when the printer 1 is provided with a display unit that can be visually recognized by the user of the printer 1 and a shift in the transport position is detected, the display on the display unit indicates to the user that the shift in the transport position has occurred. You may make it guide.

  Further, the calculation method for the width dimension, the average width dimension, the standard deviation, etc. of the marker 11 is not limited to the present embodiment. For example, when calculating the average width dimension and the standard deviation, The calculation may be performed on the width dimension of the marker 11.

  Furthermore, in the present embodiment, the transport unit 16 is used as a plurality of transport means for transporting the recording medium 2, but the present invention is not limited to this. For example, the transport unit 16 faces each recording head 10. The provided platen roller 12 may be used as a conveying unit.

1 is a conceptual diagram showing an embodiment of a printer according to the present invention. Block diagram showing the printer of FIG. The conceptual diagram which shows the marker of the recording medium shape recorded with the printer of FIG. 1 is a flowchart illustrating a method for detecting a conveyance deviation of a recording medium in the printer of FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Printer 2 Recording medium 5a 1st recording unit 5b 2nd recording unit 5c 3rd recording unit 5d 4th recording unit 6 Ink ribbon 10 Recording head 11 Positioning marker 11a Front end edge 11b Rear end edge 12 Platen roller 14a 1st sensor 14b 2nd sensor 14c 3rd sensor 14d 4th sensor 16a 1st conveyance unit 16b 2nd conveyance unit 16c 3rd conveyance unit 16d 4th conveyance unit 17A, 17B Conveyance roller 19 Stepping motor 23 Control part 24 Drive part 25 Width calculation part 26 Average width calculation unit 27 Difference calculation unit 28 Standard deviation calculation unit 29 Comparison / determination unit

Claims (4)

A plurality of recording units which are provided in parallel along the recording medium conveyance path and record images on the recording medium;
Among the recording units, a first recording unit that is disposed on the most upstream side in the conveyance direction of the recording medium and records a marker having a predetermined width dimension on the recording medium;
A plurality of conveying means provided corresponding to the respective recording units and conveying the recording medium;
Detecting means corresponding to each recording unit, provided facing the recording medium, and detecting a leading edge and a trailing edge of the marker;
With the leading edge and the trailing edge detected by each detecting means, the width dimension when the marker is conveyed at a position facing each detecting means,
The average width dimension of the marker is calculated by the width dimension and the marker width dimension calculated before calculating the width dimension,
While calculating the difference between the width dimension and the average width dimension, calculating a standard deviation of the width dimension of the marker based on the difference,
And a control unit that compares the difference with a predetermined multiple of the standard deviation and determines that a conveyance deviation has occurred when the difference exceeds a predetermined multiple of the standard deviation. . Each conveying means is a conveying roller, and each conveying roller is driven by a stepping motor,
The control unit calculates a width dimension of the marker based on the number of driving steps when the leading edge is detected by the detecting means and the number of driving steps when the trailing edge is detected. The printer according to claim 1.   The marker is a positioning marker that is recorded in the vicinity of the recording start position of the image on the recording medium and serves as a reference when recording the image on each recording head. The printer according to claim 2. An image is recorded on the recording medium by a plurality of recording units provided in parallel along the recording medium conveyance path, and the recording unit is arranged on the most upstream side in the conveyance direction of the recording medium. The recording medium transport position shift in a printer that records a marker having a predetermined width dimension on the recording medium by one recording unit and transports the recording medium by a plurality of transporting means provided corresponding to each recording unit. A detection method,
Corresponding to each recording unit, the detection means provided facing the recording medium detects the leading edge and the trailing edge of the marker,
The front edge and the rear edge calculate the width dimension when the marker is conveyed at a position facing each detection means,
According to the width dimension of the marker calculated before calculating the width dimension and the width dimension, the average width dimension of the marker is calculated,
While calculating the difference between the width dimension and the average width dimension, calculating a standard deviation of the width dimension of the marker based on the difference,
A method for detecting a deviation in a conveyance position of a recording medium in a printer, which compares the difference with a predetermined multiple of the standard deviation and determines that a conveyance deviation has occurred when the difference exceeds a predetermined multiple of the standard deviation.

Images