JP2015059027A - Conveyance device, image recording apparatus, and detection method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a conveyance device, an image recording apparatus and a detection method, capable of detecting a slippage amount when a slippage in the width direction is generated between a guide roller and a long belt-like body.SOLUTION: A conveyance device includes: a correction mechanism 14 for correcting a position of a long belt-like body 9 in the width direction, a first detection section 15, and a control section 40 for controlling them. The correction mechanism 14 comprises: a guide roller 52 rotating while contacting the long belt-like body 9; and a moving mechanism for moving the guide roller 52 in the width direction. The guide roller 52 has a pattern 60 for measurement on an outer peripheral surface of the same. The first detection section 15 detects change with time of the relative positional relation in the width direction between the pattern 60 for measurement and an edge 91 of the long belt-like body 9. Thereby, the slippage amount of the long belt-like body 9 against the guide roller 52 in the width direction is detected.

Description

  The present invention relates to a transport device that transports a long belt-like body in the longitudinal direction thereof, an image recording apparatus including the transport device, and a detection method used in these devices.

  2. Description of the Related Art Conventionally, there has been known an ink jet type image recording apparatus that records an image on a printing paper by ejecting ink from a plurality of heads while conveying a long belt-like printing paper. This type of image recording apparatus has a correction mechanism that corrects a positional deviation in the width direction of the printing paper accompanying conveyance in order to suppress meandering of the printing paper. As this correction mechanism, for example, it is conceivable to use a meandering control device described in Patent Document 1.

JP 2005-8410 A

  The conventional correction mechanism detects the edge of the printing paper, and controls the position in the width direction of the printing paper by operating the guide roller so that the detected edge position approaches the target position. However, as the printing paper conveyance speed increases, the difference between the operation amount of the guide roller and the actual movement amount of the printing paper increases. This is considered to be caused mainly by slippage between the guide roller and the printing paper. For this reason, if the slip amount of the printing paper with respect to the guide roller is detected and the slip amount can be used as a control parameter, it is considered that the position in the width direction of the printing paper can be controlled more accurately.

  The present invention has been made in view of such circumstances, and when a slip in the width direction occurs between the guide roller and the elongated belt-like body, a conveyance device, an image recording device, and the like that can detect the slip amount, And to provide a detection method.

  In order to solve the above-mentioned problem, the first invention of the present application is a transport device that transports a long strip in the longitudinal direction, and corrects the position of the long strip in the width direction orthogonal to the longitudinal direction. A correction mechanism; and a control unit that controls the correction mechanism, wherein the correction mechanism is a guide roller that rotates while being in contact with the elongated belt-like body, and a moving mechanism that moves the guide roller in the width direction. The guide roller has a measurement pattern on an outer peripheral surface thereof, and detects a time-dependent change in the positional relationship in the width direction between the measurement pattern and the edge of the elongated strip. 1 detection part is further provided.

  According to a second invention of the present application, in the transfer device according to the first invention, the control unit controls the front movement mechanism based on a detection result of the first detection unit.

  According to a third aspect of the present invention, in the conveyance device according to the first or second aspect, the encoder further includes an encoder that detects a rotational position of the guide roller, and the first detection unit includes the measurement pattern and the elongated strip. A light irradiating unit that irradiates light to an imaging region including an edge of the imaging unit, and an imaging unit that acquires an image of the imaging region, and the control unit has a detection signal from the encoder having a predetermined rotational position. When illuminating, the light irradiating unit is irradiated with light, and the photographing unit is caused to acquire an image of the photographing region.

  According to a fourth invention of the present application, in the transport device according to any one of the first invention to the third invention, the measurement pattern includes a plurality of different positions in the width direction and in the rotation direction of the guide roller. Includes a mark.

  According to a fifth invention of the present application, in the transport device according to any one of the first to fourth inventions, the measurement pattern includes a plurality of first marks arranged at first intervals in the width direction, and the width direction. And a plurality of second marks arranged at a second interval different from the first interval.

  A sixth invention of the present application is the conveying device according to any one of the first to fifth inventions, wherein the position of the edge of the elongated strip in the width direction is located upstream or downstream in the conveying direction from the guide roller. The second detection unit further includes a second detection unit that detects lower detection accuracy than the first detection unit, and the detection range in the width direction of the second detection unit is the first detection unit. It is wider than the detection range in the width direction of the detection unit.

  A seventh invention of the present application is an image recording apparatus, comprising any one of the conveying apparatuses from the first invention to the sixth invention, and a recording head that discharges ink to the long belt-like body.

  An eighth invention of the present application is a detection method, comprising: a measuring pattern provided on an outer peripheral surface of a guide roller that is in contact with the long band-shaped body while conveying the long band-shaped body in the longitudinal direction; A change with time in the positional relationship in the width direction relative to the edge of the strip is detected.

  According to the first to eighth inventions of the present application, when a slip in the width direction occurs between the guide roller and the long belt-like body, the slip amount can be detected.

  In particular, according to the second invention of the present application, the position in the width direction of the long strip can be corrected more precisely by using the slip amount between the guide roller and the long strip as a control parameter.

  In particular, according to the third invention of the present application, the photographing unit can acquire an image of the photographing region at a specific rotational position. For this reason, it is possible to detect the relative position of the edge of the long band with respect to the measurement pattern at a specific rotational position.

  In particular, according to the fourth invention of the present application, the position in the width direction of each mark can be specified based on the positional relationship in the rotation direction of the plurality of marks. Therefore, the position of the edge of the long belt-like body can be detected with each mark as a reference.

  In particular, according to the fifth aspect of the present invention, the position in the width direction of each mark can be specified based on the positional relationship between the first mark and the second mark. Therefore, the position of the edge of the long belt-like body can be detected with each mark as a reference.

  In particular, according to the sixth invention of the present application, when the edge of the elongated strip or the measurement pattern is out of the detection range of the first detector, the second detector is used to detect the edge of the elongated strip. The position can be detected.

It is the figure which showed the structure of the image recording device. It is a top view of the conveying device in the vicinity of the guider. It is a horizontal sectional view of the 2nd detection part and printing paper. It is the flowchart which showed the flow of the process of meander correction. It is the figure which showed the relationship between the detection signal output from an encoder, and the timing of lighting / extinguishing of a light irradiation part. It is the figure which showed the example of image data. It is the figure which showed the example of image data. It is the figure which showed the example of image data. It is the figure which showed the example of image data.

  Embodiments of the present invention will be described below with reference to the drawings.

<1. Configuration of Image Recording Device>
FIG. 1 is a diagram showing a configuration of an image recording apparatus 1 according to an embodiment of the present invention. The image recording apparatus 1 ejects ink from a plurality of recording heads 21 to 24 to the printing paper 9 while transporting the printing paper 9 that is a long belt-like body, and thereby an inkjet that records a color image on the printing paper 9. This is a printing apparatus of the type. As shown in FIG. 1, the image recording apparatus 1 includes a conveyance device 10, an image recording unit 20, a fixing processing unit 30, and a control unit 40.

  The transport device 10 is a mechanism for transporting the printing paper 9 in the longitudinal direction. The conveyance device 10 of the present embodiment includes an unwinding unit 11, a plurality of conveyance rollers 12, a winding unit 13, a guider 14, a first detection unit 15, and a second detection unit 16. The printing paper 9 is fed out from the unwinding unit 11 and conveyed along a conveyance path constituted by a plurality of conveyance rollers 12. Each transport roller 12 guides the printing paper 9 to the downstream side of the transport path by rotating about the horizontal axis. Further, the printed printing paper 9 is collected to the winding unit 13.

  As shown in FIG. 1, the printing paper 9 moves below the image recording unit 20 in parallel with the arrangement direction of the plurality of recording heads 21 to 24. At this time, the recording surface of the printing paper 9 is directed upward (the recording heads 21 to 24 side). Further, when the printing paper 9 comes into contact with the plurality of conveying rollers 12, tension is applied to the printing paper 9. Thereby, slack and wrinkles of the printing paper 9 during conveyance are suppressed.

  The guider 14 is a correction mechanism that corrects the position of the printing paper 9 in the width direction (horizontal direction orthogonal to the longitudinal direction). The guider 14 is disposed upstream of the image recording unit 20 in the conveyance path. The first detection unit 15 and the second detection unit 16 are sensors that detect the position of the printing paper 9 in the width direction. When transporting the printing paper 9, the control unit 40 controls the guider 14 based on detection signals from the first detection unit 15 and the second detection unit 16. Thereby, the position of the printing paper 9 in the width direction is corrected, and the meandering of the printing paper 9 is suppressed.

  Detailed configurations of the guider 14, the first detection unit 15, and the second detection unit 16 will be described later.

  The image recording unit 20 is a mechanism that ejects ink droplets onto the printing paper 9 conveyed by the conveying device 10. The image recording unit 20 of this embodiment includes a Y color head 21, an M color head 22, a C color head 23, and a K color head 24. These recording heads 21 to 24 have a plurality of nozzles arranged in the width direction. Each of the recording heads 21 to 24 has a color component of Y (Yellow), M (Magenta), C (Cyan), and K (Black) as color components of the color image from a plurality of nozzles toward the upper surface of the printing paper 9. Each ink droplet is ejected. Thereby, a color image is recorded on the upper surface of the printing paper 9.

  The fixing processing unit 30 is a mechanism for fixing the ink ejected onto the printing paper 9. The fixing processing unit 30 is disposed downstream of the four recording heads 21 to 24 in the transport direction. For example, the fixing processing unit 30 blows a heated gas onto the printing paper 9 to vaporize the solvent in the ink attached to the printing paper 9, thereby fixing the ink on the printing paper 9. However, the fixing processing unit 30 may fix the ink on the printing paper 9 by solidifying the ink by heating or light irradiation.

  The control unit 40 is means for controlling the operation of each unit in the image recording apparatus 1. The control unit 40 of the present embodiment is configured by a computer having an arithmetic processing unit 41 such as a CPU, a memory 42 such as a RAM, and a storage unit 43 such as a hard disk drive. As indicated by broken lines in FIG. 1, the control unit 40 includes the unwinding unit 11, the winding unit 13, the guider 14, the first detection unit 15, the second detection unit 16, and the four recording heads 21 to 24. And the fixing processing unit 30 are electrically connected to each other. The control unit 40 temporarily reads the computer program 44 stored in the storage unit 43 into the memory 42, and the arithmetic processing unit 41 performs arithmetic processing based on the computer program 44, thereby controlling the operation of each unit described above. To do. Thereby, the printing process in the image recording apparatus 1 proceeds.

  The control unit 40 is electrically connected to the server 2 installed outside the image recording apparatus 1. The server 2 stores print data D to be printed. During the printing process, the printing paper 9 is transported by the transport device 10, and the control unit 40 reads the designated print data D from the server 2, and based on the print data D, the recording heads 21 to 24 print each color. Of ink. As a result, an image corresponding to the print data D is recorded on the upper surface of the print paper 9.

<2. About Guider, First Detection Unit, and Second Detection Unit>
Next, a more detailed configuration of the above-described guider 14, the first detection unit 15, and the second detection unit 16 will be described. FIG. 2 is a top view of the transport device 10 in the vicinity of the guider 14. FIG. 3 is a horizontal sectional view of the second detection unit 16 and the printing paper 9.

  As shown in FIGS. 1 and 2, the guider 14 includes a first guide roller 51, a second guide roller 52, an encoder 53, and a moving mechanism 54.

  The first guide roller 51 and the second guide roller 52 are disposed at a position higher than the front and rear transport rollers 12 and at the same height. The second guide roller 52 is located downstream of the first guide roller 51 in the conveyance path. The relative positions of the first guide roller 51 and the second guide roller 52 are fixed by a pair of side plates 55. The first guide roller 51 and the second guide roller 52 rotate around the horizontal axis while bringing their outer peripheral surfaces into contact with the surface of the printing paper 9. As a result, the printing paper 9 is guided downstream (in the direction of the white arrow in FIG. 2) of the conveyance path.

  The encoder 53 is connected to the rotation shaft of the second guide roller 52. The encoder 53 detects the rotational position of the second guide roller 52 and outputs a detection signal corresponding to the rotational position. The output detection signal is transmitted to the control unit 40. As the encoder 53, for example, an optical rotary encoder that detects transmission / cutoff of light through a disc having a plurality of holes may be used. However, for the encoder of the present invention, various known encoders such as a magnetic encoder that detects the rotational position using magnetic force can be used.

  The moving mechanism 54 is a mechanism that swings the first guide roller 51, the second guide roller 52, the encoder 53, and the pair of side plates 55 around a predetermined vertical axis as a unit. When the moving mechanism 54 is operated, the second guide roller 52 moves in the width direction as indicated by a solid arrow in FIG. Further, when the second guide roller 52 moves in the width direction, the printing paper 9 that contacts the second guide roller 52 is also displaced in the width direction. Thereby, the position of the printing paper 9 in the width direction is corrected.

  The moving mechanism of the present invention is not limited to the above structure. For example, the printing paper 9 may be displaced in the width direction by sliding the second guide roller in the width direction.

  As shown in FIG. 2, the second guide roller 52 has a measurement pattern 60 including a plurality of marks 61 on the outer peripheral surface thereof. The measurement pattern 60 is formed, for example, by providing fine irregularities on the surface of the second guide roller 52 by etching or the like. As shown in FIG. 2, the measurement pattern 60 is disposed in the vicinity of one of the left and right ends of the outer peripheral surface of the second guide roller 52. At least a part of the measurement pattern 60 is exposed on the surface of the second guide roller 52 without being covered with the printing paper 9.

  The first detection unit 15 is a mechanism for detecting the positional relationship between the measurement pattern 60 and the edge 91 of the printing paper 9 on the surface of the second guide roller 52. The first detection unit 15 includes a light irradiation unit 71, a photographing unit 72, and an image processing unit 73. Both the light irradiation unit 71 and the imaging unit 72 are fixedly disposed in the vicinity of the second guide roller 52. The light irradiation unit 71 irradiates light such as white light toward the imaging region 70 including both the measurement pattern 60 and the edge 91 of the printing paper 9. The imaging unit 72 is configured by a camera having an imaging element such as a CCD and a lens, for example. The imaging unit 72 images the imaging area 70 irradiated with light and acquires image data of the imaging area 70.

  In addition, as conceptually shown in FIG. 2, the encoder 53, the light irradiation unit 71, and the imaging unit 72 are each electrically connected to the control unit 40. The control unit 40 controls the operations of the light irradiation unit 71 and the imaging unit 72 based on the detection signal received from the encoder 53. Thereby, the timing for acquiring the image data can be synchronized with the rotation of the second guide roller 52.

  The image data acquired by the imaging unit 72 is transmitted from the imaging unit 72 to the image processing unit 73. The image processing unit 73 is configured by, for example, an electronic circuit board. The image processing unit 73 performs image processing such as edge extraction on the image data, thereby detecting the relative positional relationship between the measurement pattern 60 and the edge 91 in the width direction and the temporal change of the positional relationship. . Then, a signal indicating the detection result is transmitted to the control unit 40. Note that the image processing unit 73 and the control unit 40 may be realized by a single computer.

  The second detection unit 16 is a mechanism for detecting the position in the width direction of the edge 91 of the printing paper 9 on the downstream side in the transport direction from the second guide roller 52. As shown in the enlarged view in FIG. 3, the second detection unit 16 includes a projector 81 and a line sensor 82. The projector 81 and the line sensor 82 are fixedly arranged on opposite sides of the edge 91 of the printing paper 9. The projector 81 irradiates parallel light toward the line sensor 82 side. The line sensor 82 includes a plurality of light receiving elements 821 arranged in the width direction.

  Outside the edge 91 of the printing paper 9, the light emitted from the projector 81 enters the light receiving element 821, and the light receiving element 821 detects the light. On the other hand, inside the edge 91, the light emitted from the projector 81 is blocked by the printing paper 9, so that the light receiving element 821 does not detect the light. The line sensor 82 detects the position of the edge 91 of the printing paper 9 based on the presence / absence of detection in each of the light receiving elements 821.

  The second detection unit 16 of the present embodiment can detect the edge 91 of the printing paper 9 in a wider range in the width direction than the imaging region 70 of the first detection unit 15. That is, the detection range in the width direction of the second detection unit 16 is wider than the detection range in the width direction of the first detection unit 15. However, the arrangement interval of the light receiving elements 821 in the second detection unit 16 is larger than the pixel width of the image data acquired by the first detection unit 15. Therefore, the detection accuracy of the second detection unit 16 is lower than the detection accuracy of the first detection unit 15.

  Note that the second detection unit 16 may be disposed upstream of the second guide roller 52 in the transport direction. Moreover, the 2nd detection part 16 of this invention is not limited to the structure of FIG. For example, instead of the configuration of FIG. 3, a reflective optical sensor, a contact sensor, or an ultrasonic sensor may be used.

<3. About meandering correction during conveyance>
Next, meandering correction performed when the printing paper 9 is conveyed will be described. FIG. 4 is a flowchart showing the flow of the meandering correction process.

  When performing meandering correction, first, imaging is performed by the first detection unit 15 while transporting the printing paper 9 (step S1). Here, the control unit 40 controls the operation of the light irradiation unit 71 and the imaging unit 72 based on the detection signal from the encoder 53. As a result, the photographing region 70 is photographed and image data is acquired.

  FIG. 5 is a diagram illustrating the relationship between the detection signal output from the encoder 53 and the timing of turning on / off the light irradiation unit 71. As shown in FIG. 5, the encoder 53 outputs a pulse P corresponding to the rotational position of the second guide roller 52 at a constant time interval. When the control unit 40 receives a pulse Pa corresponding to a specific rotation position from the encoder 53 (that is, when the second guide roller 52 is in a specific rotation position), the control unit 40 turns on the light irradiation unit 71 to perform imaging. The region 70 is irradiated with light. In addition, at the same time as the light irradiation unit 71 is turned on, the photographing unit 72 performs photographing. As a result, a plurality of image data is acquired every predetermined time. The plurality of acquired image data are all data when the second guide roller 52 is at a specific rotational position.

  Next, the image processing unit 73 determines whether or not the relative positional relationship in the width direction between the measurement pattern 60 and the edge 91 of the printing paper 9 can be detected based on the acquired image data (step). S2). Here, an attempt is made to extract the edge 91 of the printing paper 9 and the measurement pattern 60 from the acquired image data. When the edge 91 and at least a part of the measurement pattern 60 can be extracted, it is determined that the relative positional relationship in the width direction can be detected. On the other hand, when at least one of the two cannot be extracted (for example, when the edge 91 of the printing paper 9 is out of the field of view of the photographing unit 72), the relative positional relationship in the width direction cannot be detected. Judge.

  When it is determined that detection is possible in step S <b> 2 (Yes in step S <b> 2), the image processing unit 73 determines the relative width between the measurement pattern 60 extracted from the image data and the edge 91 of the printing paper 9. The positional relationship of directions is detected (step S3).

  FIG. 6 is a diagram illustrating an example of image data acquired by the imaging unit 72. As shown in FIG. 6, the measurement pattern 60 of the present embodiment includes a plurality of marks 61 arranged regularly. Further, as described above, since shooting is performed based on the detection signal of the encoder 53, a specific mark 61 (hereinafter, “reference mark 61a”) is located at the central position C in the rotation direction in any acquired image data. Is called). Therefore, in any image data, the relative position W in the width direction of the edge 91 of the printing paper 9 with respect to the reference mark 61a can be detected.

  When the second guide roller 52 is moved in the width direction by the moving mechanism 54 of the guider 14, the positions of the edge 91 of the printing paper 9 and the measurement pattern 60 in the image data are also displaced in the width direction. However, if both the reference mark 61a and the edge 91 of the printing paper 9 are included in the range of the image data, the relative position W in the width direction of the edge 91 of the printing paper 9 with respect to the reference mark 61a is set as follows. Can be detected.

  In addition, the plurality of marks 61 included in the measurement pattern 60 of the present embodiment are different from each other in the position in the width direction and the position in the rotation direction. For this reason, the position in the width direction of each mark 61 can be specified based on the positional relationship of the plurality of marks 61 in the rotation direction. Therefore, in the acquired image data, even if the position of the reference mark 61a is shifted upward or downward from the central position C in the rotation direction, the reference mark 61a is based on the positional relationship with the other marks 61. Can be specified. Therefore, the relative position W in the width direction of the edge 91 of the printing paper 9 with respect to the reference mark 61a can be detected.

  Further, even if the reference mark 61a is hidden behind the printing paper 9 as shown in FIG. 7 due to the sliding of the printing paper 9 with respect to the second guide roller 52, the position of the reference mark 61a is estimated from the positions of the other marks 61. be able to. Therefore, the relative position W in the width direction of the edge 91 of the printing paper 9 with respect to the reference mark 61a can be detected.

  In addition, the image processing unit 73 detects the above-described change in the relative position W with time based on the plurality of acquired image data. Then, a slip amount in the width direction of the printing paper 9 with respect to the second guide roller 52 (a change amount per unit time of the relative position W) is calculated from the detected temporal change of the relative position W. As described above, the image recording apparatus 1 according to the present embodiment prints the absolute position of the edge 91 of the printing paper 9 within the fixed visual field, the relative position W of the edge 91 with respect to the reference mark 61a, and the printing with respect to the second guide roller 52. The slip amount in the width direction of the sheet 9 can be acquired as a control parameter used for meandering correction.

  The acquired information on the absolute position, the relative position W, and the slip amount of the edge 91 is transmitted from the image processing unit 73 to the control unit 40. The control unit 40 determines the operation amount of the moving mechanism 54 based on the absolute position, the relative position W, the slip amount, and the preset target position in the width direction of the printing paper 9 (step S4). . For example, first, the operation amount of the moving mechanism 54 is calculated so that the difference between the absolute position of the edge 91 and the preset target position becomes small. Then, the calculated operation amount is corrected based on information on the relative position W and the slip amount. Thereby, the operation amount of the moving mechanism 54 reflecting the information on the relative position W and the slip amount is determined.

  Here, various methods are conceivable as to how the slip amount is reflected in the operation amount of the moving mechanism 54. For example, the operation amount of the moving mechanism 54 may be increased by the detected slip amount. Further, when the slippage amount exceeds a preset threshold value, the operation amount of the moving mechanism 54 may be limited to suppress further slipping of the printing paper 9.

  On the other hand, when the amount of movement of the second guide roller 52 in the width direction by the moving mechanism 54 is large, or when the amount of slippage of the printing paper 9 is large, in step S2, the edge 91 of the printing paper 9 and the measurement pattern 60 are measured. Or at least one of them cannot be extracted. In that case, in step S2, it is determined that detection by the first detection unit 15 is not possible (No in step S2). In that case, the image recording apparatus 1 detects the position of the edge 91 of the printing paper 9 using the second detection unit 16 (step S5). That is, the position of the edge 91 of the printing paper 9 is detected based on the presence / absence of detection in the plurality of light receiving elements 821 of the line sensor 82.

  The detection result of the second detection unit 16 is transmitted to the control unit 40. The control unit 40 determines the operation amount of the moving mechanism 54 based on the detection result and a preset target position in the width direction of the printing paper 9 (step S6). Specifically, the operation amount of the moving mechanism 54 is determined so that the detected position of the edge 91 approaches the target position of the edge 91.

  When the operation amount of the moving mechanism 54 is determined in step S4 or step S6, the control unit 40 operates the moving mechanism 54 by the operation amount (step S7). Accordingly, the second guide roller 52 moves in the width direction according to the operation amount. As a result, the position of the printing paper 9 in the width direction is corrected, and the meandering of the printing paper 9 is suppressed. As described above, the image recording apparatus 1 according to the present embodiment corrects the position in the width direction of the printing paper 9 using the slip amount in the width direction of the printing paper 9 with respect to the second guide roller 52 as one of the control parameters. . Thereby, the meandering of the printing paper 9 can be corrected accurately.

  Thereafter, the control unit 40 determines whether or not to continue meandering correction (step S8). When the meandering correction is continued (in the case of Yes in step S8), the process returns to step S1 and photographing by the first detection unit 15 is performed. On the other hand, when the meandering correction is to be terminated (No in step S8), the series of processes is terminated without returning to step S1.

<4. Modification>
Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment.

  For example, instead of the measurement pattern 60 of FIGS. 6 and 7, a measurement pattern 60 as shown in FIG. 8 may be used. The measurement pattern 60 in FIG. 8 includes a plurality of first marks 611 arranged in the width direction and a plurality of second marks 612 arranged in the width direction. An interval (first interval) d1 between the plurality of first marks 611 and an interval (second interval) d2 between the plurality of second marks 612 are different from each other. In this way, the position in the width direction of each mark 611, 612 can be specified based on the positional relationship between the first mark 611 and the second mark 612. Therefore, the relative position of the edge 91 of the printing paper 9 can be detected using the arbitrary marks 611 and 612 as reference marks.

  It should be noted that the plurality of marks 61 included in the measurement pattern 60 are preferably those that provide high contrast with the printing paper 9. That is, it is preferable that the contrast of the printing paper 9 with respect to the mark 61 is higher than the contrast of the printing paper 9 with respect to a portion other than the mark 61 on the surface of the second guide roller 52. In this way, at least when the edge 91 of the printing paper 9 overlaps the mark 61, the position of the edge 91 can be detected accurately and stably by image processing.

  Further, on the surface of the second guide roller 52, a plurality of marks 61 may be arranged so as to be continuous in the width direction. Then, the edge of the printing paper 9 always overlaps with any mark 61. Therefore, the position of the edge 91 can be detected more stably.

  Further, a measurement pattern 60 as shown in FIG. 9 may be used. In the measurement pattern 60 of FIG. 9, annular marks 61 that are continuous in the rotation direction are arranged at equal intervals in the width direction. In this case, following the movement of the second guide roller 52 in the width direction, the photographing unit 72 is also moved in the width direction so that the relative position of the photographing unit 72 with respect to the second guide roller 52 is always constant. The position of each mark 61 within the field of view of the imaging unit 72 is also fixed. Therefore, the position in the width direction of each mark 61 can be specified in the acquired image data. Therefore, the relative position of the edge 91 of the printing paper 9 can be detected using each mark 61 as a reference mark. Further, if the marks 61 are continuous in the rotation direction for one week, it is not necessary to synchronize the timing for acquiring the image data with the signal of the encoder 53.

  In the above-described embodiment, the measurement pattern including the plurality of marks 61 is illustrated. However, the measurement pattern 60 does not necessarily include the plurality of marks 61. If the fluctuation of the imaging region 70 is small and one mark 61 is always located in the field of view of the imaging unit 72, the measurement pattern 60 may be configured with only that one mark 61.

  Further, in the above embodiment, the operation of the guider 14 is controlled based on the detected slip amount. However, a mechanism for adjusting the tension of the printing paper 9 is provided in the transport device 10, and according to the slip amount. The tension of the printing paper 9 may be adjusted.

  In the above-described embodiment, the first detection unit 15 and the second detection unit 16 detect the edge 91 on the same side of the printing paper 9, but the first detection unit 15 and the second detection unit 16 The opposite edge 91 of the printing paper 9 may be detected.

  Moreover, in said embodiment, although the line sensor was used for the 2nd detection part 16, you may replace this with a simpler sensor. For example, a sensor that detects only whether the position of the edge 91 is out of the left or right when the position of the edge 91 of the printing paper 9 is out of the field of view of the first detection unit 15 is used as the second detection unit. May be. In this way, a system that can cope with a case where the positional deviation of the edge 91 is large can be configured at a lower cost.

  In the above embodiment, the four recording heads 21 to 24 are provided in the image recording apparatus 1, but the number of recording heads in the image recording apparatus 1 may be 1 to 3, There may be five or more. For example, in addition to Y, M, C, and K colors, a head that discharges special color inks may be provided.

  The image recording apparatus 1 records an image on the printing paper 9 as a recording medium. However, the image recording apparatus of the present invention may record an image on a sheet-like recording medium (for example, a resin film) other than general paper. Moreover, the conveying apparatus of this invention may convey the metal or glass long strip | belt-shaped body. Moreover, the conveying apparatus of this invention may convey an elongate strip | belt shaped object for the objectives other than printing.

  Further, the detailed shapes of the transport device and the image recording apparatus may be different from those in the present application. Moreover, you may combine suitably each element which appeared in said embodiment and modification in the range which does not produce inconsistency.

DESCRIPTION OF SYMBOLS 1 Image recording device 9 Printing paper 10 Conveying device 14 Guider 15 1st detection part 16 2nd detection part 20 Image recording part 21-24 Recording head 30 Fixing process part 40 Control part 44 Computer program 51 First guide roller 52 2nd guide Roller 53 Encoder 54 Moving mechanism 60 Measurement pattern 61 Mark 61a Reference mark 70 Imaging area 71 Light irradiation unit 72 Imaging unit 73 Image processing unit 81 Projector 82 Line sensor 91 Edge 821 Light receiving element

Claims (8)

A transport device for transporting a long strip in the longitudinal direction,
A correction mechanism for correcting the position in the width direction perpendicular to the longitudinal direction of the long band-shaped body;
A control unit for controlling the correction mechanism;
With
The correction mechanism is
A guide roller that rotates while in contact with the elongated belt-like body;
A moving mechanism for moving the guide roller in the width direction;
Have
The guide roller has a measurement pattern on its outer peripheral surface,
A transport apparatus further comprising a first detection unit that detects a temporal change in a positional relationship in the width direction between the measurement pattern and the edge of the long band-shaped body. In the conveyance apparatus of Claim 1,
The said control part is a conveying apparatus which controls a front movement mechanism based on the detection result of a said 1st detection part. In the conveyance apparatus of Claim 1 or Claim 2,
An encoder for detecting the rotational position of the guide roller;
The first detection unit includes:
A light irradiating unit for irradiating light to an imaging region including the measurement pattern and the edge of the elongated strip;
A photographing unit for obtaining an image of the photographing region;
Have
When the detection signal from the encoder indicates a predetermined rotational position, the control unit causes the light irradiation unit to emit light and causes the photographing unit to acquire an image of the photographing region. In the conveyance apparatus in any one of Claim 1- Claim 3,
The measurement pattern includes a plurality of marks, each of which has a different position in the width direction and a position in the rotation direction of the guide roller. In the conveyance apparatus in any one of Claim 1- Claim 4,
The measurement pattern is
A plurality of first marks arranged at first intervals in the width direction;
A plurality of second marks arranged in a second interval different from the first interval in the width direction;
Conveying device including. In the conveyance apparatus in any one of Claim 1- Claim 5,
A second detection unit that detects a position of the edge of the elongated strip in the width direction on the upstream side or the downstream side in the transport direction from the guide roller;
The detection accuracy of the second detection unit is lower than the detection accuracy of the first detection unit,
The conveyance device in which a detection range in the width direction of the second detection unit is wider than a detection range in the width direction of the first detection unit. A transport apparatus according to any one of claims 1 to 6,
A recording head for ejecting ink onto the long strip,
An image recording apparatus comprising:   The relative width direction of the measurement pattern provided on the outer peripheral surface of the guide roller that contacts the long band-shaped body and the edge of the long band-shaped body while conveying the long band-shaped body in the longitudinal direction A detection method for detecting a temporal change in the positional relationship of the.

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