Inkjet serial printer

Abstract

An inkjet serial printer according to the present invention is provided with: a conveyance means for conveying a medium in which labels are attached to a release sheet in a row at regular intervals; a nozzle row for discharging ink droplets to the labels conveyed by the conveyance means; a movement means for reciprocating the nozzle row in a width direction of the labels; an antenna for carrying out wireless communication for writing information to RFID tags included in the labels conveyed by the conveyance means; and a control means for controlling the conveyance means, the nozzle row, and the movement means, the control means performing control so that the labels are conveyed by a prescribed distance by the conveyance means each time the nozzle row discharges ink droplets while being moved in order to form images on the labels by serial inkjetting, and the control means controlling the conveyance means so that the conveyance of the labels is suspended when the RFID tags are present within a communication range of the antenna in a section in which the RFID tags pass through the communication range.

Description

Inkjet serial printer Field of application of the invention

[0001] The present invention relates to an inkjet serial printer. Description of related art

[0002] There is a serial inkjet printer that prints on a label using a roll sheet in which a release sheet with labels attached in a peelable manner at regular intervals is wound in a roll as a printing medium (Japanese Patent Application Laid-Open No. 2019-181893).

[0003] A serial inkjet printer includes a mechanism for conveying a label, a head for ejecting ink droplets, and a mechanism for reciprocally moving the head along a width direction intersecting the conveying direction of the label.

[0004] The head is provided with a large number of nozzles for ejecting ink droplets along the direction of conveying the label, and a nozzle row is formed by the large number of nozzles. By moving the head in the width direction over the label, ink droplets can be ejected in a strip shape for the length of the nozzle row. Next, the mechanism for conveying the label conveys the label to the position where the next ink droplet is to be ejected so that there is no gap in the image. The head is moved again in the opposite direction to the previous one, and ink droplets are ejected in a strip shape for the length of the nozzle row. A serial inkjet printer repeats this operation to complete one image.

[0005] In recent years' serial inkjet printers, in order to improve productivity, the number of nozzles of the head has been increased and the nozzle row has been lengthened in the conveying direction of the label. When the nozzle row is lengthened, the length of the ink that can be ejected in a strip shape in one head movement becomes longer, so the number of head movements required to complete an image can be reduced. In recent years, there are also inkjet printers that use a head having a nozzle row of 1 inch (25 mm).

[0006] A serial inkjet printer is needed that can print images onto labels that are peelably attached to a release sheet at regular intervals, and write information to a memory (for example, an RFID tag) attached to each label. An RFID tag is a small tag that exchanges information wirelessly and has an internal IC chip that can write information to its memory.

[0007] Such printers are used to print unique serial numbers onto labels and also write the same serial number information to RFID tags attached to those labels, thereby issuing labels.

[0008] To write to RFID tags attached to labels, serial inkjet printers are equipped with antennas that communicate with RFID tags along the transport path where the labels are transported. The inkjet printer communicates wirelessly with the RFID tags using the antennas and writes information to them. Numerous labels are attached to the release sheet in a line along the transport direction, but in order to write to each RFID tag attached to each label individually, it is necessary to be able to communicate with only one RFID tag at a time.

[0009] To achieve this, the communication range of the antenna in the transport direction is set so that only one RFID tag is within its range. For example, if the distance between RFID tags in the transport direction of a label is 16 mm, meaning the length of the portion without an RFID tag is 16 mm, then setting the communication range of the antenna in the transport direction of the label to less than 16 mm (e.g., 14 mm) will ensure that even if the labels are lined up and attached to the release sheet, only one RFID tag will be within the communication range of the antenna.

[0010] By setting the antenna's communication range in the transport direction in this way, it is possible to individually write information to RFID tags that are transported together with labels when printing serially. The antenna's communication range is set to match the shortest spacing between RFID tags in the transport direction among the labels that the inkjet printer supports.

[0011] When an inkjet printer prints on labels that are longer in the transport direction using a serial method, if the length of the transported label exceeds the length of the antenna's communication range, the RFID tag may pass through the antenna's communication range without stopping due to the transport of the label after the ink droplets have been ejected while the print head moves.

[0012] For example, consider printing an image with a length of 125 mm in the transport direction. When printing with a head with a nozzle row length of 25 mm, the inkjet printer transports the label five times to complete the image. Each time the inkjet printer ejects an ink droplet while moving the head, it transports the label 25 mm.

[0013] When the label is transported 25 mm after the ink droplet is ejected, the RFID tag is also transported 25 mm. If the antenna's communication range in the direction of label transport is 14 mm, and there is a communication range within the 25 mm transport of the RFID tag, the RFID tag will pass through the communication range with the antenna without stopping.

[0014] Even in this case, in order to write information to the RFID tag, the label transport speed is set so that the time it takes for the RFID tag to pass through the antenna's communication range is equal to the time it takes to write to the RFID tag, ensuring that the information can be written to the RFID tag in time. However, there is a problem in that applying the transport speed that allows writing to the RFID tag to all transports when printing using a serial method reduces productivity.

[0015] This invention solves the above problems, and its purpose is to improve productivity, even slightly, in serial inkjet printers.

[0016] A typical configuration of the first invention for achieving the above objective is characterized by comprising: a transport means for transporting a media in which labels are attached in a line at regular intervals to a release sheet; a nozzle row for ejecting ink droplets onto the labels transported by the transport means; a moving means for reciprocating the nozzle row in the width direction of the label; an antenna for wireless communication for writing information to RFID tags included in the labels transported by the transport means; and a control means for controlling the transport means, the nozzle row, and the moving means, wherein the transport means controls the transport means to transport the label a predetermined distance each time ink droplets are ejected while moving the nozzle row to form an image on the label in a serial inkjet manner, and controls the transport means to temporarily suspend the transport of the label when the RFID tag is within the communication range of the antenna in a section in which the RFID tag passes through the communication range of the antenna.

[0017] A typical configuration relating to the second invention for achieving the above objective is characterized by comprising: a transport means for transporting a media in which labels are attached in a row at regular intervals to a release sheet; a nozzle row for ejecting ink droplets onto the labels transported by the transport means; a moving means for reciprocating the nozzle row in the width direction of the label; an antenna for performing wireless communication to write information to an RFID tag included in the label transported by the transport means; and a control means for controlling the transport means, the nozzle row, and the moving means, wherein the transport means is controlled to transport the label a predetermined distance each time ink droplets are ejected while moving the nozzle row to form an image on the label in a serial inkjet manner, and the transport means is controlled such that the time required to transport the label a predetermined distance in at least one other section is shorter than the time required to transport the label a predetermined distance in the section in which the label is transported a predetermined distance and the RFID tag passes through the communication range of the antenna.

[0018] A representative configuration of the third invention for achieving the above objective is an inkjet serial printer having a dispensing means for dispensing labels from a roll-shaped media in which labels are attached to a release sheet at regular intervals, a nozzle row for ejecting ink droplets onto the labels dispensed from the dispensing means, and a moving means for moving the nozzle row back and forth in the width direction of the label, characterized in that it has an antenna for performing wireless communication for writing information to a memory embedded in the label, and a control means for controlling the dispensing means such that the time required for the label to travel a predetermined distance in at least one other section is shorter than the time required for the label to travel a predetermined distance in the section in which the memory embedded in the label passes through the communication range of the antenna.

[0019] Further features of the present invention will become apparent from the following description of exemplary embodiments, which will be explained in conjunction with the accompanying drawings.

[0020] This figure shows the external appearance of an image forming apparatus.

[0021] This is a cross-sectional view showing the schematic configuration of an image forming apparatus.

[0022] This is a control block diagram of an image forming apparatus.

[0023] This is a diagram illustrating roll sheets.

[0024] This diagram shows the communication range of an RFID antenna.

[0025] This diagram shows the communication range based on the spacing of RFID antennas.

[0026] This diagram illustrates the behavior when the first embodiment is not implemented.

[0027] This is a diagram illustrating the behavior when the first embodiment is implemented.

[0028] This is a flow chart of the image forming operation in the first embodiment.

[0029] This diagram illustrates the behavior when the number of labels exceeding the data writable range after being transported a predetermined distance is one.

[0030] This diagram illustrates the behavior when the number of labels exceeding the data writable range after being transported a predetermined distance is two.

[0031] It is an explanatory diagram of the behavior when the second embodiment is not implemented.

[0032] It is an explanatory diagram of the behavior when the second embodiment is implemented.

[0033] It is a flowchart of the image forming operation in the second embodiment.

[0034] It is an explanatory diagram of the behavior when the tag is not within the communication range before conveyance.

[0035] It is an explanatory diagram of the behavior when the tag is within the communication range before conveyance.

[0036] It is an explanatory diagram of printing by the serial method.

[0037] It is an explanatory diagram of the behavior when the third embodiment is implemented.

[0038] It is a graph explaining the conveyance speed of the label in the third embodiment.

[0039] It is a graph showing an example of changing the conveyance speed according to the section where the tag passes through the communication range.

[0040] It is a graph showing an example of changing the conveyance speed according to the section where the tag passes through the communication range.

[0041] It is an explanatory diagram of the area of the RFID tag to which information is to be written.

[0042] It is an explanatory diagram of the communication range by the writing unit.

[0043] It is an explanatory diagram of the behavior when the fourth embodiment is implemented.

[0044] It is a flowchart showing the conveyance procedure of the label.

[0045] It is a flowchart showing the conveyance procedure of the label. Description of the Embodiment

[0046] Next, an embodiment of the image forming apparatus according to the present invention will be specifically described with reference to the drawings.

[0047] [First Embodiment] <Overall Configuration of Image Forming Apparatus> Figure 1 is a perspective view showing the image forming apparatus of this embodiment. The image forming apparatus 100 is an inkjet serial printer installed on a tabletop. The image forming apparatus 100 comprises an image forming apparatus body 101 equipped with an operation unit 102 consisting of a liquid crystal touch panel, and a roll sheet holder 103 for loading a roll sheet in which the medium is wound into a roll shape. The image forming apparatus 100 transports the roll sheet by a transport unit and forms an image based on data received from a host computer 104, according to labels, which are recording media, that are continuously attached to the roll sheet at regular intervals.

[0048] Figure 2 is a schematic cross-sectional view of the image forming apparatus 100 of this embodiment. The image forming apparatus 100 grasps the roll sheet 200 loaded in the roll sheet holder 103 with a transport roller 202 and a pinch roller 203 (hereinafter referred to as the transport mechanism), which are transport and unloading means, and transports it in the unloading and downstream direction. The transport mechanism for transporting the roll sheet 200 is not limited to one using a pair of rollers as in this embodiment, and may also transport the roll sheet 200 by suctioning it to a suction belt. However, a configuration using transport rollers as the transport mechanism is preferred from the viewpoint of the external dimensions of an inkjet serial printer installed on a tabletop.

[0049] Downstream of the conveyor roller 202, a tip detection sensor 204 is positioned which is capable of detecting the tip of a label attached to a sheet S that has been unwound from the roll sheet 200 and conveyed.

[0050] The tip detection sensor 204 detects the tip of the label, and the image forming unit is operated in synchronization with the transport of the sheet S with the label attached to the release sheet to form an image on the label. The image forming unit in this embodiment is a serial inkjet type. A motor pulley is attached to the shaft of the motor, which is used as a means of transport. The carriage 201 is fixed to a belt that is stretched between the motor pulley and another pulley. The carriage 201 is held so as to be slidable in the width direction intersecting the transport direction, with the shaft passing through it. By driving the motor, the carriage 201 is moved along the shaft in the width direction of the sheet S. The head 210 (see Figure 3) mounted on the carriage 201 moves in one direction along the width direction, ejecting ink droplets onto the label in accordance with the image signal to form an image.

[0051] The print head 210 is equipped with a nozzle row for each ink color to be ejected. In this embodiment, the nozzle row for one ink color has 1200 nozzles arranged in the transport direction at a pitch of 1200 DPI, and the length of the nozzle row is 25 mm. The nozzle row for each color is arranged in the width direction.

[0052] An RFID antenna 404 is positioned downstream of the image forming unit. When an RFID tag 403 (see Figure 4) embedded in the label is transported within the communication range of the RFID antenna 404, data is written to the RFID tag 403 via communication from the RFID antenna 404. In this embodiment, an RFID antenna 404 is used that has a pattern formed on a printed circuit board using metal foil. The communication range of the RFID antenna 404 is the range in which the metal foil pattern is arranged. While an RFID antenna 404 using a coil can also be used, an antenna with a pattern arranged on a printed circuit board is preferred from the viewpoint of miniaturization and thinning.

[0053] As described above, the sheet S, on which an image has been formed on the label and data has been written to the RFID tag 403, is discharged from the sheet discharge port of the image forming apparatus 100. Position management for image formation and antenna communication is achieved by counting the amount of movement from the tip detection sensor 204 to an encoder when not in view. This encoder is mounted to rotate in conjunction with the rotation of the transport roller 202 that transports the roll sheet 200, and detects the rotation speed of the transport roller 202.

[0054] <Control Unit> Figure 3 is a block diagram showing the configuration of the control unit that controls the operation of the image forming apparatus 100 in this embodiment. The image forming apparatus 100 performs image forming operations and writing operations to RFID tags based on control signals from the control unit.

[0055] In Figure 3, the main controller 301 is a control means for controlling the image forming apparatus 100. The main controller 301 has functions as a storage unit for storing data, a data control unit, and a setting unit for changing the operation of the main unit based on setting data. The main controller 301 is connected to the host computer 104 and they exchange signals with each other.

[0056] 302 is connected to the main controller 301 and is a ROM that stores control programs, etc. The main controller 301 uses the RAM 303 as working memory according to these programs. 304 is an image buffer that stores data transmitted from the host computer 104. 305 is a head drive circuit that drives a heating element built into the head 210, and a driver controller 306 connected to the main controller 301 controls the head drive circuit 305 according to the bitmap data stored in the image buffer to form an image. 307 is a drive circuit that drives a transport motor (not shown) provided in the transport unit, etc., and is controlled by the main controller 301. The screen displayed on the LCD of the operation unit 102 and the behavior when the user operates the touch panel are also controlled by the main controller 301.

[0057] Furthermore, detection is performed by the tip detection sensor 204 connected to the sensor board 308. The RFID controller 310 is also controlled by the main controller 301 and can write RFID write data received from the host computer 104 to the RFID tag via the RFID antenna 404, and read information from the RFID tag via the RFID antenna 404.

[0058] <Reading and Writing RFID Tags> Figure 4 shows a roll sheet (roll-shaped media) 200. The roll sheet 200 is made by winding a sheet S, on which labels 402 are attached in a row at regular intervals to a release sheet 401, into a roll shape. An RFID tag 403 is embedded (contained) inside the label 402. As an example of embedding, in the case where the RFID tag 403 is attached to the release sheet 401 side of the label 402, there is an adhesive layer on the release sheet 401 side of the label 402 and the release sheet 401 side of the RFID tag 403. Alternatively, the label 402 may have a three-layer structure with the RFID tag 403 placed in the middle layer, so that the label 402 is inside the RFID tag 403. When referring to a label containing an RFID tag, this includes both the form where the RFID tag 403 is attached to the label 402 and the form where the RFID tag 403 is inside the label 402. Here, we have described a printing medium in which a sheet S is wound into a roll, but a medium in which a sheet S is repeatedly folded in a mountain fold and valley fold to form an accordion shape can also be used for printing.

[0059] The RFID tag 403 consists of an IC chip containing memory and an antenna connected to it. In this embodiment, the RFID tag is also simply referred to as the tag. The entire RFID tag is also referred to as the memory. RFID stands for Radio Frequency Identification, and it is a technology that performs contactless wireless communication between an antenna on a reader / writer and an RFID tag using radio waves with frequencies from 130 kHz to 2.45 GHz. Examples of RFID include those that communicate with RFID tags using the LF band (130 kHz to 135 kHz), HF band (13.56 MHz), and UHF band (860 to 920 MHz). In addition, there are those that communicate with tags using the Type-A, Type-B, and Type-F standards of near-field communication (NFC) using 13.56 MHz. Furthermore, writing to the memory may be done using wireless communication at other frequencies.

[0060] The RFID tag 403 is read from and written to by the RFID antenna 404. As shown in Figure 5, reading and writing are only possible when the RFID tag 403 is located within the communication range 405 of the RFID antenna 404.

[0061] For the writing to the RFID tag 403 to be completed while it is passing through the communication range, the transport speed must be such that the time it takes to pass through the communication range is longer than the time required to write the data to the RFID tag 403. However, printing at this transport speed would reduce productivity.

[0062] Figures 5(a) and 5(c) show a state where more than half of either the left or right side of the RFID tag is within the communication range 405. Figure 5(b) shows a state where the center of the RFID antenna 404 and the RFID tag overlap, and the entire RFID tag is within the communication range 405.

[0063] Figure 6 shows the communication range 405 based on the positional distance between the RFID antenna 404 and the RFID tag 403 embedded in the transported label 402. Figure 6(a) is a schematic diagram showing the communication range 405 of the RFID antenna 404 when the distance between adjacent RFID tags 403 is wide. Figure 6(b) is a schematic diagram showing the communication range 405 of the RFID antenna 404 when the distance between adjacent RFID tags 403 is narrow.

[0064] The communication range of the RFID antenna 404 must be set so that only one RFID tag 403 contained within a single label is included in the communication range, in order to prevent accidental writing to other tags. This is because individual information, such as a serial number, is written to individual RFID tags. Therefore, the closer the RFID tags 403 contained in adjacent labels are, the narrower the communication range must be for reading and writing to the RFID tags.

[0065] The communication range of the RFID antenna 404 is set to match the shortest spacing in the transport direction of the RFID tags 403 among the labels that the image forming apparatus 100 corresponds to. For example, when the spacing in the transport direction of the label is 16 mm from one RFID tag to the next, that is, when the length of the part without an RFID tag is 16 mm, if the communication range of the antenna in the transport direction of the label is set to less than 16 mm (for example, 14 mm), then even if the RFID tags are attached side by side on the release sheet, only one RFID tag will be within the communication range of the antenna.

[0066] <Writable Label Transport to RFID Tags> In this embodiment, when writing to an RFID tag while printing with an inkjet serial printer, the control means controls the transport means so that when the RFID tag is within the communication range of the antenna, the transport of the label is temporarily suspended.

[0067] Specifically, the carriage 201, which is equipped with the head 210, transports a predetermined distance (one section) of sheet for each scan. The transport is performed at a speed such that the time it takes for the RFID tag 403 to pass through the communication range is shorter than the time required to write to the RFID tag 403. If the transport exceeds the communication range with the RFID tag 403 after one section, the transport is performed for a distance shorter than the predetermined distance, but just enough to reach the writing position, before writing to the RFID tag 403. Then, the remaining distance that was not enough to reach the ink droplet ejection position is transported, and image formation is resumed. A specific example of roll sheet transport for this purpose is shown below.

[0068] First, we will describe an example of transporting a roll sheet 200 to move the data writing position when the RFID tag 403 to be data written to exceeds the communication range of the RFID antenna 404 during transport.

[0069] Figure 7 shows the behavior of the label 402 when the data writing position transfer transport according to this embodiment is not performed, and Figure 8 shows the behavior of the label 402 when the data writing position transfer transport according to this embodiment is performed. Both will be explained starting from the initial state shown in Figures 7(a) and 8(a). Figures 7(a) and 8(a) show a state where there are two image-formed labels 402 directly below the carriage 201 (section X), and the label 402 is being transported to directly below the RFID antenna 404 in the next sheet transport of section X length.

[0070] If the data writing position transfer transport according to this embodiment is not performed, sheet transport starts from the state in Figure 7(a) at a predetermined transport speed over a predetermined distance, resulting in the state in Figure 7(b). In this case, the RFID tag to be written to (tag 1 in the figure) is transported beyond the communication range 405. Similarly, in the next transport, Figure 7(c), the second and third RFID tags 403 are also transported beyond the communication range 405. At this time, the time it takes for the RFID tag to pass through the communication range 405 due to the predetermined distance of sheet transport is shorter than the time required to complete the writing process. Therefore, the writing process to the RFID tag cannot be completed while the RFID tag is passing through the communication range 405, and the tag is ejected without data being written. However, if printing is performed at a transport speed where the time it takes for the RFID tag to pass through the communication range 405 is longer than the time required to complete the writing process, productivity will decrease.

[0071] In contrast, when transport for moving the data writing position according to this embodiment is performed, if it is determined that the RFID tag to be written to (tag 1 in the figure) exceeds the communication range 405 in the next sheet transport from the state in Figure 8(a), the label 402 is transported to a position where the RFID tag to be written to 403 and the communication range 405 overlap, at a distance shorter than a predetermined distance, as shown in Figure 8(b-1).

[0072] In the example shown in Figure 8, the RFID tag 403 to be written to is transported so that its center and the center of the communication range 405 overlap. At this time, no image is formed on the label 402; only transport and data writing to the RFID tag 403 are performed. By aligning the center of the RFID tag 403 with the center of the communication range 405, the area where the RFID tag 403 and the communication range overlap becomes larger, making it less likely for communication errors to occur when the communication sensitivity is increased.

[0073] Subsequently, it is determined whether the RFID tag to be written to (tag 2 in the figure) exceeds the communication range 405. If it does not, the tag is transported as shown in Figure 8(b-1), and the distance that was insufficient for transporting to the next ink droplet ejection position is transported to form an image on the label 402 (see Figure 8(b-2)).

[0074] Figures 8(c-1) to (c-3) show examples of cases where multiple RFID tags 403 exceed the communication range during a single transport. In Figure 8(c-1), similar to Figure 8(b-1), if it is determined that the RFID tag to be written to (tag 2 in the figure) exceeds the communication range 405, the sheet is transported to a position where the RFID tag to be written to (tag 2 in the figure) and the communication range 405 overlap, and data is written to the RFID tag 403.

[0075] Subsequently, it is determined whether the RFID tag to be written to (tag 3 in the figure) exceeds the communication range 405. If it does, the sheet is transported again to a position where the RFID tag to be written to (tag 3 in the figure) and the communication range 405 overlap, and data is written to the RFID tag. This operation is repeated for each RFID tag 403 that exceeds the communication range in a single transport. In Figure 8(c-3), similar to Figure 8(b-2), the sheet is transported the remaining distance that was insufficient to reach the position where the next ink droplet will be ejected after being transported up to Figure 8(c-2), and an image is formed on the label 402.

[0076] Next, the transport control procedure for moving the data writing position according to this embodiment will be described with reference to the flowchart in Figure 9. In this flowchart, execution starts when the host computer 104 or other instruction unit instructs the data writing to the RFID tag 403 or the image formation operation on the label 402. In the flowchart in Figure 9, S900 acquires RFID tag information. The information acquired here is:

[0077] (1) Distance from the detection of the leading edge of the sheet to the communication range (2) Length of the RFID tag's communication range

[0078] The above information may be information received from the host computer that the user entered into the printer driver, or it may be information obtained from the detection result of a communication range detection operation performed when changing sheets.

[0079] After image formation begins, the system waits in S901 for the media to reach the image formation start position. Once the media reaches the image formation start position, S902 calculates the number of sheets that will exceed the data writeable range in the next transport.

[0080] (Example of calculating the number of excess tags) Here, a specific example of calculating the number of tags exceeding the communication range will be explained with reference to Figures 10 and 11, assuming the following values ​​for predetermined distance, label length, etc. Note that the following values ​​are examples provided to facilitate understanding of the number calculation, and the present invention is not limited to these values.

[0081] L1: Predetermined distance (transport distance per section) = 25 mm L2: Label length = 10 mm L3: Gap length between labels = 2 mm L4: Distance from sheet tip detection to communication range = 2 mm L5: RFID tag communication range length = 6 mm L6: Distance from tip detection sensor to the center of RFID antenna = 40 mm

[0082] (Example 1) As shown in Figure 10(a), an example of calculation when the tip of the first label is located at a distance of 23 mm from the tip detection sensor 204 will be explained.

[0083] First, all labels detected by the tip detection sensor 204 are transported a predetermined distance L1 minute from their current position, and it is determined whether the tag center exceeds the distance L6 from the tip detection sensor 204 to the center position of the RFID antenna 404.

[0084] - Center of the first tag: 23 mm - (L4 + L5 / 2) = 18 mm from the tip detection point. - Center of the first tag after transporting a predetermined distance L1 minute from the current position: 18 mm + L1 = 43 mm

[0085] Therefore, since the distance is greater than L6, as shown in Figure 10(b), when transported a predetermined distance L1 minutes from the current position, the center of the first tag will exceed the center position of the RFID antenna 404. Therefore, the excess number is incremented.

[0086] On the other hand, if the tip of the first label is located at a distance of 23 mm from the tip detection sensor 204 as described above, the tip of the second label is located at a distance of 23 mm - (L2 + L3) = 11 mm from the tip detection sensor 204 (see Figure 10(a)).

[0087] - Center of the second tag: 11 mm - (L4 + L5 / 2) = 6 mm from the tip detection point. - Center of the second tag after transporting a predetermined distance L1 minute from the current position: 6 mm + L1 = 31 mm

[0088] Therefore, because it is less than the distance L6, even if the tag is transported a predetermined distance L1 minutes from the current position, the center of the second tag will not exceed the center position of the RFID antenna 404.

[0089] Therefore, if the leading edge of the first label is located 23 mm from the leading edge detection sensor 204, the number of labels that exceed the data writable range when transported a predetermined distance L1 minute from the current position is 1.

[0090] (Example 2) Next, as shown in Figure 11(a), we will explain an example of calculation when the tip of the first label is located at a distance of 33 mm from the tip detection sensor 204.

[0091] - Center of the first tag: 33 mm - (L4 + L5 / 2) = 28 mm from the tip detection point. - Center of the first tag after transporting a predetermined distance L1 minute from the current position: 28 mm + L1 = 53 mm

[0092] Therefore, since the distance is greater than L6, as shown in Figure 11(b), when transported a predetermined distance L1 minutes from the current position, the center of the first tag will exceed the center position of the RFID antenna 404. Therefore, the excess number is incremented.

[0093] When the tip of the first label is located at a distance of 33 mm from the tip detection sensor 204, the tip of the second label is located at a distance of 33 mm - (L2 + L3) = 21 mm from the tip detection sensor 204 (see Figure 11(a)). At this time,

[0094] - Center of the second tag: 21 mm - (L4 + L5 / 2) = 16 mm from the tip detection point. - Center of the second tag after transporting a predetermined distance L1 minute from the current position: 16 mm + L1 = 41 mm

[0095] Therefore, since the distance is greater than L6, as shown in Figure 11(b), if the tag is transported a predetermined distance L1 minutes from the current position, the center of the second tag will also exceed the center position of the RFID antenna 404. Therefore, the excess number is incremented.

[0096] Even after transporting a predetermined distance L1 minute, the center of the third tag does not exceed the center position of the RFID antenna 404. Therefore, if the tip of the first label is located 33 mm from the tip detection sensor 204, the number of tags that exceed the data writable range when transported a predetermined distance L1 minute from the current position is two.

[0097] Once the number of pages exceeding the data writeable range has been calculated as described above, in the flowchart of Figure 9, S903 determines whether the remaining number of pages to be written, calculated from the "number of pages exceeding the data writeable range in the next transport" calculated in S902, has reached zero. If it is determined in S902 that there is an excess of one or more pages, the remaining number of pages to be written will be the number calculated in S902, and if there are zero pages, it will be 0.

[0098] If it is determined in S903 that the remaining number of tags to write is not zero, the process proceeds to S904. In S904, the RFID tag 403 to be data written is transported so that its center aligns with the center of the RFID antenna 404. When this transport is completed and stops (a 0.2-second pause), the process proceeds to S905, and the data write position transport flag is changed to ON. Then, the data is written to the RFID tag 403 (S906). After the writing to the RFID tag 403 is complete, the remaining number of tags to write is decremented (S907). The process again checks in S903 whether the remaining number of tags to write is not zero, and if it is not zero, the process from S904 is repeated.

[0099] If it is determined in S903 that the remaining number of pages to write is 0, the process proceeds to S908 to determine if the data writing position transport flag is ON. If the data writing position transport flag is not ON, data transport for writing to the RFID tag 403 has not been performed, so the data is transported a predetermined distance and image formation is carried out (S909). If the data writing position transport flag is ON, data transport for writing to the RFID tag 403 has been performed, so the data is transported a distance that was not sufficient to eject the ink droplet and image formation is carried out (S910).

[0100] (Example of calculating label transport distance) Here, a specific example of calculating the distance that was not reached to the position where the ink droplet was ejected in S910 will be explained using the example shown in Figures 10(a) and 11(a) above.

[0101] (Example 1) When the number of excess tags is 1 (as in Figure 10(a)) As shown in Figure 10(a), if the tip of the first label is located at a distance of 23 mm from the tip detection sensor 204, transporting it for a predetermined distance L1 minutes from the current position will cause the center of the first tag to exceed the data writeable range (see Figure 10(b)). Therefore, in the state shown in Figure 10(a), the center of the first tag is located at a distance of 18 mm from the tip detection sensor 204, as described above.

[0102] (1) Transport to the data writing position of the first tag The distance from the center of the first tag to the center of the RFID antenna is L6 - 18 mm = 22 mm (Figure 10(c)), and data writing to the tag is performed.

[0103] (2) Transport to the label image formation position The distance that is not yet reached to the position where the next ink droplet is ejected: L1 - 22 mm = 3 mm (Figure 10(d)), and image formation on the label is performed.

[0104] (Example 2) When the number of excess tags is two (as in Figure 11(a)) As shown in Figure 11(a), if the tip of the first label is located at a distance of 33 mm from the tip detection sensor 204, transporting the tags a predetermined distance L1 minutes from the current position will cause the centers of the first and second tags to exceed the data writeable range (see Figure 11(b)).

[0105] (1) Transport to the data writing position of the first RFID tag When the state is as shown in Figure 11(a), the center of the first RFID tag is located 28 mm from the tip detection sensor 204 as described above, so the center of the first RFID tag is transported a distance of L6 - 28 mm = 12 mm to the center of the RFID antenna (Figure 11(c)), and data is written to the first RFID tag.

[0106] (2) Transport to the data writing position of the second RFID tag When the state is as shown in Figure 11(a), the center of the second RFID tag is 16 mm from the tip detection sensor 204 as described above, and as described above, it has been transported 12 mm to write data to the first RFID tag, so the distance from the center of the second RFID tag to the center position of the RFID antenna is L6 - (16 mm + 12 mm) = 12 mm (Figure 11(d)), and data writing to the second RFID tag is performed.

[0107] (3) Transport to the label image formation position As described above, the first and second RFID tags are transported 12 mm + 12 mm = 24 mm for data writing, so the remaining distance, L1 - 24 mm = 1 mm, is transported to perform image formation on the label (Figure 11(e)).

[0108] As described above, the sheet is transported, writing is performed to the RFID tag 403, and an image is formed on the label 402. Then, in the flowchart of Figure 9, at S911, it is determined whether there are any remaining labels 402 to be image formed. If there are, the process returns to S901 and waits for the labels 402 to reach the image formation position again. If there are no more labels to be image formed, the process proceeds to S912, and the image formation completion process is performed to end the flow.

[0109] The image formation completion process here includes all completion processes related to the image formation operation, such as ejecting the image-formed label from the image forming apparatus and cleaning the print head. Even when performing image formation and data writing on RFID tags 403 of a length less than a predetermined distance by transporting the image forming medium, as in this embodiment, it is possible to perform image formation and data writing on small-sized RFID tags 403 by inserting a transport operation that writes to the RFID tags 403 while performing the image formation operation.

[0110] In this embodiment, for the sake of clarity, as mentioned above, movement into the communication range is defined as the point where the centers of the RFID tag 403 and the RFID antenna 404 overlap. That is, the writing position is defined as the position where the center of the RFID tag 403 and the center of the RFID antenna 404 overlap, and the RFID tag 403 of the label is moved to the writing position before data is written. In actual control, the communication range changes depending on the state of the tag and antenna, so the setting of the writing position is not limited to this. The communication range and writing position are set by the strength of the radio waves emitted from the RFID antenna 404, as well as by a calibration operation called calibration (acquisition of label information) performed by the image forming apparatus 100.

[0111] Furthermore, if the center of the RFID tag 403 and the center of the RID antenna 404 coincide during transport over a predetermined distance L1 minute, transport over the predetermined distance L1 minute is performed to carry out both the image formation operation on the label and the writing operation on the RFID tag.

[0112] <Acquiring Label Information> This section describes how to acquire information about the location of the RFID tag 403 attached to the label 402 and how to detect the communication range in which the RFID antenna 404 can communicate with the RFID tag 403. The main controller 301 starts detecting the communication range upon instruction from the user.

[0113] First, the main controller 301 obtains the label length, the spacing between labels, and the presence or absence of an RFID tag from the information of the label 402 input by the user to the image forming apparatus 100. If an RFID tag is present in the information input to the image forming apparatus 100, it detects the communication range. The main controller 301 drives the transport motor to move the transport section and transports the leading edge of the label 402 to the position of the RFID antenna 404. At this time, the main controller 301 controls the position of the label 402 using the detection result of the leading edge detection sensor 204 and signals from the encoder that detects the rotation speed of the transport roller 202 that transports the roll sheet 200.

[0114] Once the tip of label 404 is transported to the position of RFID antenna 404, transport is stopped and a communication test is performed. This communication test detects whether or not the RFID antenna 404 can communicate with the RFID tag. Next, label 404 is transported 1 mm and stopped, and a communication test is performed. This is repeated until communication with the RFID tag is no longer possible with one label, thereby detecting the position of the RFID tag 403 within one label 402 and detecting the communication range, which is the range of positions on label 402 where communication with the RFID tag is possible. The main controller 301 detects the communication range for three labels and sets the communication range with the RFID tag by averaging the results. From the length and spacing of label 402, the position of the RFID tag, and the communication range, it is possible to determine which label and which section the RFID tag 403 passes through the communication range. In the sequence described above, this information is used to align the center of the RFID tag 403 with the center of the communication range.

[0115] As explained above, in this embodiment, the transport mechanism is controlled to temporarily suspend label transport when the RFID tag is within the communication range of the antenna, so there is no need to reduce the transport speed in other sections. Therefore, writing to the RFID tag can be performed without reducing productivity.

[0116] Furthermore, the information on label 402 may be obtained not only from information input by the user to the image forming apparatus 100, but also from media information registered in the printer driver. If the media information includes the location of the RFID tag, the communication range detection operation can be omitted by setting the communication range based on that information.

[0117] In this embodiment, we have described a system that writes to an RFID tag, but it is not limited to this; it may also perform reading, or both writing and reading. In that case, the time for which the RFID antenna is stopped at the center position is changed depending on the processing performed on the RFID tag. For example, 0.1 seconds for reading, 0.3 seconds for writing and reading, etc. By stopping the antenna only for the time required for each process, the processing can be completed while the RFID tag is within the communication range.

[0118] Although the printing method in this embodiment is a serial inkjet method, it can be applied not only to unidirectional printing, in which the carriage 201 moves in one direction while ejecting ink droplets, but also to bidirectional printing, in which the carriage 201 moves in both directions while ejecting ink droplets.

[0119] [Second Embodiment] In the first embodiment described above, even if the RFID tag 403 is already within the communication range of the RFID antenna 404 before sheet transport, the sheet was transported in such a uniform manner that data was written at a predetermined writing position where the center of the RFID antenna 404 and the center of the RFID tag 403 overlap.

[0120] However, even if the centers of the RFID tag 403 and the RFID antenna 404 do not coincide before sheet transport, if they are able to communicate with each other, writing can be performed without transporting the sheet to the data writing location as described above. This can further improve productivity by reducing unnecessary sheet transport.

[0121] Therefore, in the second embodiment, even if the number of sheets exceeds the data-writable range in the next transport as described above, if the RFID tag 403 and the RFID antenna 404 are within the communication range, data is written to the RFID tag 403 without performing sheet transport.

[0122] The following provides a specific example of how to transport the sheets for this purpose. Figure 12 shows the behavior of the label 402 when transport for moving the data writing position according to this embodiment is not performed, and Figure 13 shows the behavior of the label 402 when transport for moving the data writing position according to this embodiment is performed. Both will be explained starting from the initial state shown in Figures 12(a) and 13(a).

[0123] In this embodiment as well, the basic sheet transport method is the same as in the first embodiment. A predetermined distance (one section) of sheet transport is performed with each scan of the carriage 201. The transport speed at this time is such that data writing to the RFID tag 403 cannot be completed when the RFID tag 403 passes through the communication range 405.

[0124] If the data writing position transfer transport according to this embodiment is not performed, sheet transport starts from the state in Figure 12(a) over a predetermined distance, and after transporting the predetermined distance, it reaches the position in Figure 12(b-3). As a result, tags 4 and 5 exceed the communication range 405. Therefore, in the embodiment described above, transport of less than the predetermined distance was performed so that the center of the RFID antenna 404 and the center of the RFID tag 403 overlapped, as shown in Figures 12(b-1) and 12(b-2).

[0125] However, since tag 4 is within the communication range of RFID antenna 404 at the time shown in Figure 12(a), it is not necessary to perform the transport shown in Figure 12(b-1).

[0126] Therefore, in this embodiment, since the position shown in Figure 13(a) (the position shown in Figure 12(a)) is a position where writing to tag 4 is possible, after writing data to tag 4, as shown in Figure 13(b-1), the tag is transported to the next target of writing, tag 5, and data is written to tag 5. Next, as shown in Figure 13(b-2), the tag is transported by the remaining distance to the position where the next ink droplet will be ejected, and an image is formed on the label. This eliminates the need for the transport process to write data to tag 4.

[0127] Figure 14 is a flowchart of the image forming operation in this embodiment. Steps S1400 to S1403 are the same as steps S900 to S903 described in the first embodiment. If it is determined in step S1403 that the remaining number of pages to be written, calculated from the "number of pages that will exceed the data writeable range in the next transport," is not zero, the process proceeds to step S1404.

[0128] In S1404, it is determined whether the RFID tag 403 to be written to is within the communication range of the RFID antenna 404. Therefore, it is determined whether the center of the RFID tag 403 and the center of the RFID antenna 404 are within the distance equal to the sum of their respective communication ranges.

[0129] (Example of calculation for determining whether it is within the communication range) Here, an example of calculation for determining whether the RFID tag 403 is within the communication range of the RFID antenna 404 will be explained with reference to Figures 15 and 16. Note that the predetermined distance, which is the transport distance per cycle, and the numerical values ​​of each part length L1 to L6, such as the label length, are the same as in the first embodiment, and further,

[0130] L7: RFID antenna communication range = 5mm in front of and behind the center

[0131] The following explanation, as with the first embodiment, provides examples of numerical values ​​for each part to facilitate understanding of whether they are within the communication range, and the present invention is not limited to these numerical values.

[0132] The communication range L7 is actually set by a communication range detection operation performed by the image forming apparatus 100 using the sheet S. Alternatively, it may be set by the user from the host computer 104.

[0133] As described above, the communication range of L7, i.e., the RFID antenna 404, is 5 mm in front of and behind the center. Therefore, the communication range from the center of the RFID tag 403 is 3 mm, and the communication range from the center of the RFID antenna 404 is 5 mm. Communication is possible if the centers of the RFID tag 403 and the RFID antenna 404 are within the wider 5 mm communication range.

[0134] (Example 1) As shown in Figure 15(a), we will explain an example of calculation when the first label is located 35 mm from the tip detection point.

[0135] - Center of the first RFID tag: 35 mm - (L4 + L5 / 2) = 30 mm from the tip detection point - Center of the first tag after transporting a predetermined distance L1 minute from the current position: 30 mm + L1 = 55 mm - Distance from the center of the first RFID tag to the center of the RFID antenna 404: L6 - 30 mm = 10 mm

[0136] Therefore, if the RFID tags are transported for a predetermined distance L1 minute, as shown in Figure 15(b), the first RFID tag will be outside the communication range of the RFID antenna 404. On the other hand, in the state before transport (position shown in Figure 15(a)), the center of the first RFID tag and the center of the RFID antenna 404 are 10 mm apart and outside the communication range. In this case, as shown in Figure 15(c), the RFID tags are transported 10 mm so that the center of the RFID tag 403 coincides with the center of the RFID antenna 404, and data is written to the first RFID tag.

[0137] (Example 2) Next, we will explain a calculation example when the first label is located 40 mm from the tip detection point, as shown in Figure 16(a). In this case,

[0138] - Center of the first RFID tag: 40 mm - (L4 + L5 / 2) = 35 mm from the tip detection point - Distance from the center of the first RFID tag to the center of the RFID antenna: L6 - 35 mm = 5 mm - Center of the first tag after transporting a predetermined distance L1 minute from the current position: 35 mm + L1 = 60 mm

[0139] In this case as well, if the tags are transported for a predetermined distance L1 minute, the first tag will be outside the communication range of the RFID antenna 404, as shown in Figure 16(b). However, in the state before transport (Figure 16(a)), the distance from the center of the first RFID tag to the center of the RFID antenna 404 is 5 mm, and at this position the first RFID tag is within the communication range.

[0140] Therefore, in this case, data is written to the first RFID tag before the label is transported. This eliminates the need to transport the first RFID tag for data writing.

[0141] As described above, if it is determined in S1404 that the device is within the communication range in the flowchart of Figure 14, the process proceeds to S1407. If it is determined that the device is outside the communication range, the process proceeds to S1405. Steps S1405 to S1413 are the same as steps S904 to S912 described in the first embodiment.

[0142] In this embodiment, as described above, if the RFID tag 403 to be data written to is within the communication range of the RFID antenna 404 before the transport operation, transport for moving to the data writing position is not performed. Therefore, image formation and writing to the RFID tag 403 can be performed without reducing productivity.

[0143] [Third Embodiment]

[0144] Next, a third embodiment will be described. In this embodiment, the time required to transport a label a predetermined distance in a serial printing method is reduced compared to the time required to transport the RFID tag a predetermined distance in the section where the RFID tag passes through the antenna's communication range. This increases productivity as much as possible in a serial inkjet printer that can write information to RFID tags and print images on labels. A specific example of roll sheet transport for this purpose will be shown and explained below.

[0145] Figure 17 illustrates the scanning of the carriage 201 and the transport of the label 402 when performing serial printing. One transport section consists of moving the carriage 201, ejecting ink droplets, and then advancing the label to the position where the next ink droplet will be ejected.

[0146] In this embodiment, the length L of the nozzle row 211 is 25 mm. (a) is a diagram showing that ink droplets are ejected while scanning the carriage 201 in the direction of arrow A, forming an image on the label 402 within the range of the length L of the nozzle row 211, that is, a region with a width of 25 mm in the transport direction.

[0147] After one scan of the carriage 201 is completed, the label 402 is transported for one section (25 mm) in the direction of arrow B, as shown in (b). Next, as shown in (c), the carriage 201 is scanned in the direction of arrow C to form an image of the nozzle row 211 again over a length L (25 mm).

[0148] In this way, the image forming apparatus 100 repeatedly moves the carriage 201 to eject ink droplets over a 25 mm length to form a part of the image, and then transports the label 402 over a predetermined distance L of 25 mm, thereby completing a seamless image.

[0149] Although the serial printing method in Figure 17 was described as bidirectional printing in which ink droplets are ejected while the carriage 201 is moved in both directions of arrows A and C, this embodiment can also be applied to unidirectional printing in which ink droplets are ejected while the carriage 201 is moved in one direction.

[0150] Figure 18 illustrates the behavior in which a label 402 containing an RFID tag 403 is transported by sheet transport over a predetermined distance L with each scan of the carriage 201. When the predetermined distance L is 25 mm and the length of the communication range is 14 mm, when the label transitions from state (b) to state (c) after transporting over the predetermined distance L (25 mm), the tag 1 moves from upstream of the communication range 405 to downstream of the communication range 405 in the sheet transport direction indicated by the arrow. In other words, in the section where the label 402 moves from (b) to (c), the tag 1 passes through the 14 mm communication range 405. ("Section in which the RFID tag passes through the communication range")

[0151] At this time, the transport speed is set so that the time that tag 1 is in the communication range 405 is longer than the time it takes to complete the data writing process. To explain with a specific example, if the length of the communication range 405 in the transport direction is 14 mm and the time required to write data to the RFID tag is 0.2 seconds, then if the average speed at which the tag passes through the communication range 405 is 70 mm / s or less, the data writing process can be completed during the 0.2 seconds that tag 1 passes through the communication range 405.

[0152] (14 mm ÷ 0.2 sec = 70 mm / s) Therefore, the transport speed for the section in which the RFID tag 403 passes through the communication range 405 is set to 70 mm / s. Note that this transport speed is the average speed. In serial printing, a predetermined distance of sheet transport is performed with each scan of the carriage 201, but one section of sheet transport, i.e., one sheet transport of a predetermined distance, includes acceleration from a stationary state and deceleration from a state in which the sheet is being transported. Since the sheet transport speed is not constant, the average speed is calculated from the time required to transport a predetermined distance and this is used as the transport speed.

[0153] When transporting from (a) to (b) or from (c) to (d) in Figure 18, there are no RFID tags 403 passing through the communication range 405. Nevertheless, if the sheet S is transported at 70 mm / s, which is the speed at which data writing can be completed in time, productivity, i.e., printing speed, will be unnecessarily reduced. Therefore, in sections where there are no RFID tags 403 passing through the communication range 405 in a single transport, the decrease in productivity can be suppressed by making the transport speed of the sheet S faster than the transport speed for data writing. In this case, the transport speed does not need to be considered in terms of the time required for data writing to the RFID tags, so it should be a speed greater than 70 mm / s. For example, by setting the transport speed to 70 mm / s in the section where an RFID tag passes through the communication range 405 in a single transport of a predetermined distance L (25 mm), and setting the transport speed to 100 mm / s in at least one other section, the decrease in productivity can be suppressed more than when the transport speed in all sections is 70 mm / s.

[0154] When transporting from (d) to (e) in Figure 18, the tag 2 stops within the communication range 405 without passing through it, and transitions to state (f) during the next predetermined distance of transport. In this case, the tag 2 remains within the communication range 405 for the duration of one scan by the carriage 201, allowing the data writing process to be completed during that time. Therefore, the transport speeds for the sections from (d) to (e) and from (e) to (f) can be faster than 70 mm / s.

[0155] Figure 19 is a graph with the vertical axis representing transport speed and the horizontal axis representing elapsed time, showing the case when the transport speed for all sections is set to 70 m / s, which is the transport speed at which writing to the RFID tag 403 can be performed, as the label 402 is transported to each position in Figure 18.

[0156] In Figure 18 (a) through (f), the label is transported five times. When transporting a 25 mm section at 70 mm / s, the time t1 required for one transport is 0.36 sec. The total time required for the five transports in Figure 18 (a) through (f) is 1.8 sec. (0.36 sec × 5 = 1.8 sec)

[0157] Figure 20 is a graph showing the transport speed when the RFID tag 403 passes through the communication range 405 when transporting the label 402 to each position in Figure 18, i.e., when transporting from (b) to (c) in Figure 18, the transport speed is set to 70 mm / s, and of the remaining four transport sections, the transport speed for one section is set to 100 mm / s and the transport speeds for the remaining three sections are set to 70 mm / s.

[0158] When transporting a 25 mm section at 100 mm / s, the required time t2 is 0.25 sec. The total time required for the five transports from (a) to (f) in Figure 18 is 1.69 sec.

[0159] (0.25sec+0.36sec×4=1.58sec)

[0160] Figure 21 is a graph showing the case where the transport speed in the section where the RFID tag 403 passes through the communication range 405 is set to 70 mm / s, the transport speed in half of the remaining four sections (two sections) is set to 100 mm / s, and the transport speed in the remaining two sections is set to 70 mm / s.

[0161] The total time required for the five transports from (a) to (f) in Figure 18 is 1.58 seconds. (0.25 seconds × 2 + 0.36 seconds × 3 = 1.58 seconds)

[0162] Using the above values, we will estimate the time required to print 100 labels, assuming that printing on one label is completed in five transport passes, and compare productivity. The label size used in this estimation is 122 mm in length in the transport direction, with a spacing of 3 mm between labels. The sum of the label length and label spacing is 125 mm, and the length of transporting one label is five sections. If the distance from the tip of the label to the tip of the RFID tag is 61 mm, the shortest distance from the label tip position at the start of printing to the end of the communication range is 90 mm, and the length of the communication range is 14 mm, then a section will occur in each label where the RFID tag passes through the communication range.

[0163] Assuming all transport speeds are 70 m / s, printing 100 sheets takes 180 seconds.

[0164] (1. 8 sec x 100 sheets = 180 sec)

[0165] If we assume that one of the four sections where the RFID tag does not pass through the communication range is 100 mm / s and the remaining three sections are 70 mm / s, then printing 100 tags will take 169 seconds.

[0166] (1.69 sec x 100 sheets = 169 sec)

[0167] If we assume that half of the four sections where the RFID tag does not pass through the communication range are at 100 mm / s and the remaining two sections are at 70 mm / s, then printing 100 tags would take 158 seconds.

[0168] (1.58 sec x 100 sheets = 158 sec)

[0169] Thus, if the transport speed for RFID tags other than when they are passing through the communication range is set to 100 mm / s, the printing time can be reduced by approximately 6% compared to when all transport speeds are set to 70 mm / s. Furthermore, if half of the transport speeds for RFID tags other than when they are passing through the communication range are set to 100 mm / s, the time required for printing can be reduced by approximately 12%.

[0170] To suppress the decline in productivity, it is sufficient to shorten the transport time in at least one section other than when the RFID tag 403 passes through the communication range 405. If the transport time is shortened in more than half of the sections other than when the RFID tag 403 passes through the communication range 405, productivity can be sufficiently improved.

[0171] Here, we will explain the area of ​​the RFID tag 403 on which data is written and the communication range 405 provided by the RFID antenna 404.

[0172] Figure 21 shows a label 402 with one RFID tag 403 embedded, and the arrow indicates the transport direction. In order to write data to the RFID tag 403 and suppress the decrease in printing productivity, the average transport speed when area A of the label 402, which includes the RFID tag 403, passes through the communication range should be set as the transport speed for data writing, and the average transport speed when areas other than A pass through the communication range should be faster than the transport speed for data writing.

[0173] Figure 23 shows an example of an RFID antenna 404 installed inside the image forming apparatus 100. Arrow D is the transport direction of the sheet S, and W is the width direction of the sheet S being transported. The RFID antenna 404 emits radio waves from a pattern 406 made of copper foil or the like. Therefore, the area B in which the pattern 406 is arranged in the direction along the transport direction of the sheet S (arrow D) can be considered as the communication range 405 with the RFID tag.

[0174] Therefore, when the RFID tag 403 passes through the communication range, it means that the tag area A shown in Figure 21 passes through the pattern area B shown in Figure 22. Also, as mentioned above, when the sheet is transported a predetermined distance L and the RFID tag 403 stops within the communication range 405 (see Figure 18(e)), data writing is performed while it is stopped. At this time, it is not necessary for the entire tag area A to be within the pattern area B; data writing is possible if a part of the tag area A is within the pattern area B.

[0175] The transport control procedure of this embodiment will be explained with reference to the flowchart in Figure 25. In this flowchart, the execution of data writing to the RFID tag 403 and image formation operations on the label 402 is initiated when instructed by an instruction unit such as the host computer 104.

[0176] In the flowchart of Figure 25, S2501 retrieves information about label 402. The information retrieved here is the distance from the tip of the label to the communication range and the length of the RFID tag's communication range. The main controller 301 identifies the section (which label and which section) in which RFID tag 403 passes through the communication range 405 from the retrieved label information. Next, in S2502, it determines the section in which the transport speed should be increased, excluding the section in which RFID tag 403 passes through the communication range 405.

[0177] Next, in S2503, 402 is transported to the printing start position. Then, in S2504, ink droplets are ejected while moving the nozzle row.

[0178] In S2505, the process branches depending on whether the next section to be transported is a section through which the RFID tag passes within the communication range. If it is a section through which the RFID tag passes, the process proceeds to S2506; otherwise, it proceeds to S2508. If the process proceeds to S2506, the transport of one section is performed at 70 mm / s.

[0179] If the process proceeds to S2506, it branches depending on whether the next section to be transported is a section where the transport speed determined in S2502 should be increased. If it is a section where the transport speed should be increased, the process proceeds to S2509 and transports at 100 mm / s. Otherwise, the process proceeds to S2506 and transports at 70 mm / s. Next, the process proceeds to step S2507, and if printing is complete, it ends; otherwise, it returns to S2504.

[0180] [Fourth Embodiment]

[0181] Next, we will explain a system that temporarily pauses an RFID tag within its communication range when it passes through the range during a single sheet transport of a predetermined distance, which is performed with each scan of the carriage.

[0182] Figure 24 shows the behavior of the sheet when an RFID tag passes through the communication range in a single transport of a predetermined distance L, and the RFID tag is transported in such a way that it stops within the communication range. In this embodiment, the predetermined distance L is 25 mm and the communication range is 14 mm. When the sheet is transported from state (b) by the predetermined distance L (25 mm), it reaches state (c-2), and the tag passes through the communication range (14 mm). If the sheet is transported at 100 mm / s at this time, writing to the RFID tag cannot be completed. Therefore, the sheet is transported in such a way that the RFID tag temporarily stops within the communication range, as shown in (c-1). In other words, the temporary stop at (c-1) is inserted during the transport of the predetermined distance L from (b) to (c-2).

[0183] By including a pause at (c-1), the time from when the RFID tag enters the communication range until it leaves is longer than the time required for the write process (0.2 sec). Even with all transport speeds set to 100 mm / s, writing to the RFID tag becomes possible, and the decrease in productivity when printing to labels and writing to RFID tags can be suppressed.

[0184] The transport control procedure of this embodiment will be explained with reference to the flowchart in Figure 26. In this flowchart, the execution of data writing to the RFID tag 403 and image formation operations on the label 402 is initiated when instructed by an instruction unit such as the host computer 104.

[0185] In the flowchart of Figure 26, S2601 acquires information about label 402. The information acquired here is the distance from the tip of the label to the communication range and the length of the RFID tag's communication range. The main controller 301 identifies the section (which section of which label) in which RFID tag 403 passes through the communication range 405 from the acquired label information. Next, S2602 transports the label to the printing start position. Then, S2603 ejects ink droplets while moving the nozzle row.

[0186] In S2604, the process branches depending on whether the next section to be transported is a section through which the RFID tag passes within the communication range. If it is a section through which the RFID tag passes, the process proceeds to S2605; otherwise, it proceeds to S2606. If the process proceeds to S2606, the normal transport of one section, i.e., transport at 100 mm / s, is performed. If the process proceeds to S2605, the RFID tag 403 is transported within the communication range and decelerated, and in S2607, the RFID tag 403 is temporarily stopped within the communication range 405. If the temporary stop time is 0.2 seconds, the time the RFID tag 403 is within the communication range can be made longer than the time required for writing. Next, in S2608, the transport of the label 402 is resumed and the remaining distance of one section is transported.

[0187] Next, the process proceeds to S2609. If printing is not complete, it returns to S2603. If printing is complete, the process terminates.

[0188] [Modification] In the embodiments described above, the explanation mainly focused on image formation in a single pass, where an image of the width of the nozzle row is formed in one scan of the carriage 201. However, the present invention is not limited to this and may be applied to image formation in multiple passes. In the case of image formation in a single pass, the width of the image formed by the carriage 201 in one scan is equal to the predetermined distance. In the case of multiple passes, the predetermined distance is shorter than the width of the image formed by the carriage 201 in one scan. Even in the case of multiple passes, the present invention can be applied if the RFID tag passes through the communication range in a single transport section where the label is advanced to the position where the next ink droplet is ejected after scanning of the carriage 201.

[0189] Furthermore, depending on the printing method, the distance of the section over which the label advances after scanning the carriage 201 during image formation in a single pass may differ. In this case as well, the present invention can be applied when the RFID tag passes through the communication range of the antenna as the label advances to the position where the next ink droplet is ejected.

[0190] Furthermore, the nozzle rows may be inclined with respect to the conveying direction.

[0191] Although the present invention has been described with reference to exemplary embodiments, the present invention is not limited to the exemplary embodiments disclosed. The scope of the following claims is given in the broadest sense to encompass all variations, equivalent structures and functions.

[0192] This application claims priority based on Japanese Patent Application No. 2024-229304, filed on 25 December 2024, and Japanese Patent Application No. 2025-279842, filed on 24 December 2025, and all of the contents of those applications are incorporated herein by reference.

Claims

1. An inkjet serial printer comprising: a transport means for transporting media in which labels are attached in a line at regular intervals to a release sheet; a nozzle row for ejecting ink droplets onto the labels transported by the transport means; a moving means for reciprocating the nozzle row in the width direction of the label; an antenna for wireless communication for writing information to an RFID tag included in the label transported by the transport means; and a control means for controlling the transport means, the nozzle row, and the moving means, wherein the transport means controls the transport means to transport the label a predetermined distance each time ink droplets are ejected while moving the nozzle row to form an image on the label in a serial inkjet manner, and controls the transport means to temporarily suspend the transport of the label when the RFID tag is within the communication range of the antenna in a section in which the RFID tag passes through the communication range of the antenna.

2. An inkjet serial printer comprising: a transport means for transporting media in which labels are attached in a row at regular intervals to a release sheet; a nozzle row for ejecting ink droplets onto the labels transported by the transport means; a moving means for reciprocating the nozzle row in the width direction of the label; an antenna for performing wireless communication to write information to an RFID tag included in the label transported by the transport means; and a control means for controlling the transport means, the nozzle row, and the moving means, wherein the transport means controls the transport means to transport the label a predetermined distance each time ink droplets are ejected while the nozzle row is moved to form an image on the label in a serial inkjet manner, and the transport means controls the transport means such that the time required to transport the label a predetermined distance in at least one other section is shorter than the time required to transport the label a predetermined distance in the section in which the label is transported a predetermined distance and the RFID tag passes through the communication range of the antenna.

3. The inkjet serial printer according to claim 2, characterized in that the control means controls the transport means such that the time required to transport the label a predetermined distance in at least half of the other sections is shorter than the time required to transport the label a predetermined distance in the section through which the RFID tag passes the communication range.

4. An inkjet serial printer having: a dispensing means for dispensing labels from a roll-shaped media in which labels are attached to a release sheet at regular intervals; a nozzle row for ejecting ink droplets onto the labels dispensed from the dispensing means; and a moving means for moving the nozzle row back and forth in the width direction of the label, wherein the inkjet serial printer is characterized by having: an antenna for performing wireless communication for writing information to a memory embedded in the label; and a control means for controlling the dispensing means such that the time required for the label to travel a predetermined distance in at least one other section is shorter than the time required for the label to travel a predetermined distance in the section in which the memory embedded in the label passes through the communication range of the antenna.

5. The inkjet serial printer according to claim 4, characterized in that the control means controls the feeding means such that the time required for the label to travel the predetermined distance in at least half of the other sections is shorter than the time required for the label to travel the predetermined distance in the section in which the memory embedded in the label passes through the communication range.

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