Printing system

Abstract

To provide a printing system that can read printed information. [Solution] The printing system of the embodiment comprises a printing unit, a detection unit, a reading unit, a transport unit, and a control unit. The printing unit prints information onto the media using low-color ink. The detection unit detects the media. The reading unit reads the printed information printed on the media detected by the detection unit. The transport unit transports the media, the printing unit, the detection unit, and the reading unit relative to each other. If the reading unit cannot read the printed information on the media, the control unit reprints the printed information on the media by overlaying it with the printing unit.

Description

Technical Field

[0001] Embodiments of the present invention relate to a printing system.

Background Art

[0002] There has been proposed a system that uses thermochromic ink to print a two-dimensional code such as a QR code (registered trademark) or a barcode as print information, enabling information to be read only when necessary and repeatedly using a printing medium.

[0003] However, generally, thermochromic ink tends to have lower color development compared to inks using ordinary pigments or dyes, and there are cases where the printed information cannot be read. In particular, when directly printing on a medium such as a corrugated box without using label paper, the readability varies depending on the color of the medium, resulting in variations in the recognition rate with a uniform ink ejection amount. Also, not only thermochromic ink but also inks with low color development cause similar problems.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] An object of the present invention is to provide a printing system capable of reading printed information.

Means for Solving the Problems

[0006] The printing system of this embodiment comprises a printing unit, a detection unit, a reading unit, a transport unit, and a control unit. The printing unit prints information onto a medium using low-color ink. The detection unit detects the medium. The reading unit reads the printed information printed on the medium detected by the detection unit. The transport unit transports the medium, the printing unit, the detection unit, and the reading unit relative to each other. If the reading unit cannot read the printed information on the medium, the control unit reprints the printed information on the medium by overlaying it using the printing unit. [Brief explanation of the drawing]

[0007] [Figure 1] Figure 1 is a block diagram showing an example configuration of a printing system according to an embodiment. [Figure 2] Figure 2 is an explanatory diagram showing an example configuration of a printing system according to an embodiment. [Figure 3] Figure 3 is a flowchart showing an example of the control operation of the printing system according to the embodiment. [Modes for carrying out the invention]

[0008] Figure 1 is a block diagram showing an example configuration of the printing system 10 according to the embodiment, and Figure 2 is an explanatory diagram showing an example configuration of the printing system 10. The printing system 10 is a system that prints print information onto a medium using low-color development ink (low-color development ink), such as thermochromic ink. Here, low-color development ink (low-color development ink) is an ink whose color development may cause reading errors in a reading device that reads print information, such as a barcode reader 16 used in the printing system 10. Thermochromic ink changes color with temperature, for example. Thermochromic ink changes from colored to colorless when heated, for example. Also, thermochromic ink has a reversible color change reaction. The medium is, for example, an article that can be printed with ink, and may include, for example, box-shaped containers such as returnable boxes and cardboard boxes, and paper media such as labels attached to these containers. In the following description, the medium may also be described as the print target object OB.

[0009] As shown in Figure 1, the printing system 10 connects a CPU 111 that controls the entire system, a ROM 112 that stores the control program, a RAM 113 that stores temporary data, and an interface 115 that inputs operation signals from an external source to the RAM 113 via a bus 119. The printing system 10 is also equipped with a barcode reader 16 as a reading unit that reads the code (print information) printed on the object to be printed OB. If the code cannot be read by the reading unit, it performs reprinting by overlaying the same code on top of the printed code. Furthermore, the printing system 10 may move the head of the printer 15 for printing in a multipath manner during reprinting, or in the case of an inline site, it may move the object to be printed OB by returning the transport mechanism that transports the object to be printed OB. A specific example of the printing system will be described below.

[0010] As shown in Figure 2, the printing system 10 includes a transport mechanism, such as a transport belt BE, on which the object to be printed OB is placed. A drive source (not shown) moves this transport belt BE, transporting the placed object to be printed OB to multiple process locations for rewriting the printed information, as indicated by the white arrows in Figure 2. This allows for either printing the printed information on the object OB, rewriting the printed information on the object OB, or reprinting the already printed information on the object OB. The multiple processes include an erasing process that erases the printed information by applying heat, a printing process that prints the necessary information again using thermochromic ink, a reading process that reads the printed information, and a reprinting process that overlays the printed information on previously printed information if the printed information cannot be read. Thus, the transport belt BE and the drive source (not shown) constitute a transport machine that transports the object to be printed OB. Although Figure 2 shows four conveyor belts BE, it is also possible to configure it as a single conveyor belt that covers all process positions, or to cover all process positions with multiple conveyor belts other than four.

[0011] The object to be printed on, OB, has a rectangular shape, such as a cardboard box or a reusable container, and a label LA of a different color from the object to be printed on, for example, white, is affixed to one side. The information to be printed is printed on this label LA. In other words, the label LA is the printing position, and the side to which the label LA is affixed is the printing surface. Furthermore, the label LA acts as a guide to the printing position, either through the difference in color from the object to be printed on OB, or through marks provided on the label LA. The printed information that guides the printing position includes a string of characters representing the destination of the object to be printed on OB, that is, the destination of the items stored in the object to be printed on OB, and at least a two-dimensional barcode such as a QR code (registered trademark) that encodes this string of characters. Note that the printed information is not limited to these and may include other information or other codes. The printing target object OB containing the items is picked up by a worker or an appropriate picking mechanism, and placed on the conveyor belt BE with the printing surface facing the side of the conveyor belt BE, that is, perpendicular to the direction of transport of the printing target object OB. Here, the label LA has printing information about the previously stored items and not the printing information about the currently stored items, so it needs to be rewritten.

[0012] The printing system 10 further comprises a control unit 11, a timing sensor 12, a label sensor 13, a heater 14, a printer 15, a barcode reader 16, a user interface 17, and one or more motors 18. The timing sensor 12, the label sensor 13, the heater 14 located at the erase process position, the printer 15 located at the printing process position, the barcode reader 16 located at the reading process position, and the user interface 17 are arranged along the conveyor belt BE.

[0013] The control unit 11 is a computer that controls the operation of each component of the printing system 10.

[0014] The timing sensor 12 is composed of, for example, a photoelectric sensor and detects when the object to be printed OB reaches the position of this timing sensor 12. Based on the time when the timing sensor 12 detects the arrival of the object to be printed OB, the control unit 11 can control the operation timing of the label sensor 13, heater 14, printer 15, and barcode reader 16 based on the movement speed of the object to be printed OB by the conveyor belt BE.

[0015] The label sensor 13 is composed of an image sensor such as a camera and captures a photograph of the object to be printed OB. The control unit 11 can detect the label LA, i.e., the printing position, on the object to be printed OB from the captured image of the object to be printed OB by known image processing. Specifically, the control unit 11 detects the distance from the front end in the transport direction on the printing surface of the object to be printed OB, the distance from the upper end of the printing surface, and the length and width dimensions. The label sensor 13 may also utilize a simple color area sensor that can detect the label LA on its own. In this way, the label sensor 13 and the control unit 11 constitute a printing position detection unit that detects the label LA on the transported object to be printed OB, acting as a position determination unit that determines the printing position of the printed information printed on the transported object to be printed OB using thermochromic ink. The label LA then constitutes a guide portion to prevent misalignment of the printing position.

[0016] The heater 14 is a heat source for erasing thermochromic ink, which irradiates the label LA with heat capable of erasing the printed information printed on the label LA using thermochromic ink. The heater 14 is supported by a support column PO so as to be movable in the height direction by a motor 18, as shown by the solid arrow in Figure 2. In this embodiment, the mechanism for converting the rotational force of the motor 18 into linear movement force of the heater 14 is not particularly limited. The support mechanism on the support column PO should be compatible with this drive force conversion mechanism. Any support mechanism is acceptable as long as the support direction of the heater 14 is perpendicular to the transport direction of the object to be printed OB, that is, from the side in the transport direction, so that heat is applied to the label LA. The control unit 11 can control the motor 18 based on the printing position determined using the label sensor 13, that is, at what height the label LA is attached to the object to be printed OB, to adjust the height position of the heater 14 to match the printing position. Furthermore, the control unit 11 can erase the printed information printed using thermochromic ink by operating the heater 14 at the timing when the printing position passes, calculated based on the detection time by the timing sensor 12. In this way, the heater 14 and the control unit 11 constitute an erasing unit that erases the printed information printed using thermochromic ink at the printing position by applying heat from a direction perpendicular to the transport direction of the object to be printed OB, using the heater 14 whose height position is adjusted according to the printing position, according to the timing when the printing position passes, which is determined based on the printing position.

[0017] The printer 15 is composed of an inkjet printer having an inkjet head that uses, for example, thermochromic ink. The printer 15 is supported by a support column PO so that it can move in the height direction by a motor 18, as shown by the solid arrow in Figure 1. The mechanism for converting the driving force of the motor 18 and the support mechanism for the printer 15 are not specified in this embodiment, similar to those for the heater 14. The printer 15 is supported by the support column PO so that it can print information on the label LA from a direction perpendicular to the transport direction of the object to be printed OB, that is, from the transport direction side. The control unit 11 can control the motor 18 based on the printing position determined using the label sensor 13, that is, at what height the label LA is attached to the object to be printed OB, to adjust the height position of the printer 15 to match the printing position. Furthermore, the control unit 11 can print information using thermochromic ink by operating the printer 15 at the timing when the printing position passes, calculated based on the detection time by the timing sensor 12. Thus, the printer 15 and control unit 11 include a printer 15 that uses thermochromic ink and is positioned downstream of the heater 14 along the transport direction. The printer 15 adjusts its height according to the timing at which the print position determined based on the print position passes, and prints information onto the object OB from a direction perpendicular to the transport direction.

[0018] The barcode reader 16 is supported by a support column PO and is movable in the height direction by a motor 18, as shown by the solid arrow in Figure 2. The motor 18's drive force conversion mechanism and the barcode reader 16's support mechanism are not defined in this embodiment. The barcode reader 16 is supported by the support column PO so that it can read the barcode in the printed information printed on the label LA from a direction perpendicular to the transport direction of the object to be printed OB, i.e., from the transport direction side. The control unit 11 can control the motor 18 based on the printing position determined using the label sensor 13, i.e., at what height the label LA is attached to the object to be printed OB, to adjust the height position of the barcode reader 16 to match the printing position. Furthermore, the control unit 11 can read the printed barcode and decode the printed information by operating the barcode reader 16 at the timing when the printing position passes, calculated based on the detection time by the timing sensor 12.

[0019] The user interface 17 is a system monitor for displaying various information from the control unit 11. The user interface 17 may also be equipped with keys and buttons for inputting various instructions to the control unit 11. The user interface 17 may also include a touch panel with touch keys on a monitor screen such as an LCD.

[0020] Furthermore, the printing system 10 of this embodiment includes a forward alignment mechanism that aligns the printing surface of the object to be printed OB, which has the printing position, with the printer head 151 of the printer 15. This mechanism is provided with a stopper plate BP and a pressing plate PP on either side of the transport belt BE in the transport direction. The stopper plate BP extends along the transport belt BE. The pressing plate PP is attached to a pressing mechanism and moves toward the stopper plate BP by the pressing mechanism. During this movement, it comes into contact with the object to be printed OB being transported by the transport belt BE, pressing the object to be printed OB toward the stopper plate BP and causing the printing surface of the object to be printed OB to abut against the stopper plate BP. As a result, the printing surface of the object to be printed OB is aligned parallel to the transport direction and transported in this state.

[0021] Note that the operation timing of the pressing plate PP is, for example, when an operator places the printing object OB on the conveying belt BE, the timing corresponding to the operation instruction by the operator. Also, when the printing object OB is placed by the pickup mechanism, it is also possible for the control unit 11 to perform timing control based on the placement operation of the pickup mechanism.

[0022] As shown in FIG. 1, the control unit 11 includes a CPU 111, a ROM 112, a RAM 113, a storage 114, an interface 115, a sensor circuit 116, a head drive circuit 117, and a motor drive circuit 118, which are connected to the CPU 111 via a bus 119. In FIG. 1, "interface" is abbreviated as "I / F".

[0023] The CPU 111 is a processor having a function of controlling the operation of the entire printing system 10. The CPU 111 realizes various functions by executing a program stored in advance in the ROM 112. The CPU 111 can execute a plurality of information processes simultaneously by using a multi-core and multi-thread one. Note that some of the various functions realized by the CPU 111 executing a program may be realized by hardware circuits such as an ASIC (Application Specific Integrated Circuit), an FPGA (field-programmable gate array), and a GPU (Graphics Processing Unit). In this case, the CPU 111 controls the functions executed by the hardware circuit.

[0024] The ROM 112 is a non-volatile memory in which a control program, control data, and the like are stored in advance.

[0025] RAM113 is volatile memory. RAM113 temporarily stores data being processed by CPU111. RAM113 may also store data necessary for program execution and program execution results. For example, RAM113 may include a temporary storage unit 1131 that stores write information to be written as print information. In Figure 1, "temporary storage unit" is abbreviated as "TMP".

[0026] Storage 114 is an auxiliary storage device such as EEPROM (Registered Trademark) (Electric Erasable Programmable Read-Only Memory), HDD (Hard Disk Drive), or SSD (Solid State Drive). Storage 114 non-volatilely stores data used by the CPU 111 in various processing operations and data generated by the processing performed by the CPU 111. Storage 114 includes, for example, a database 1141 that stores printed information read by the barcode reader 16. In Figure 1, "database" is abbreviated as "DB".

[0027] Interface 115 is an interface for sending and receiving data with external devices via a network such as a LAN. Interface 115 may also be an interface for reading and writing data to and from removable memory media such as USB memory or memory cards.

[0028] The sensor circuit 116 is connected to the timing sensor 12, the label sensor 13, and the barcode reader 16, and receives signals or data from them and transmits them to the CPU 111.

[0029] The head drive circuit 117 drives the printer head 151 of the printer 15 based on print data that is input from the CPU 111 and stored in the temporary storage unit 1131 of the RAM 113.

[0030] The motor drive circuit 118 controls the driving of the motor 18, belt motor 19, and press motor 20 according to signals from the CPU 111. The motor drive circuit 118 can independently control the motor 18 for the heater 14, the motor 18 for the printer 15, and the motor 18 for the barcode reader 16. The belt motor 19 is a motor for driving the conveyor belt BE. Only one belt motor 19 is shown as a representative example, and there may be multiple belt motors. The press motor 20 is a motor for the pressing mechanism that moves the pressing plate PP. However, in a configuration where the operation of the pressing mechanism is performed according to operation instructions from the operator, this press motor 20 does not need to be connected to the motor drive circuit 118.

[0031] Furthermore, the user interface 17 and heater 14 can also be connected to the bus 119 directly or via an interface not shown, and controlled by the CPU 111. In Figure 1, "user interface" is abbreviated as "UI".

[0032] Figure 3 is a flowchart illustrating an example of the control operation of the control unit 11. When the CPU 111 is powered on, it displays an operation menu on the user interface 17 according to the program stored in the ROM 112, and executes the operations shown in this flowchart in response to the print start operation on the user interface 17. In parallel with the operations shown in this flowchart, the CPU 111 can also execute the operation of storing the write information input, received, or read via the user interface 17 or interface 115 in the temporary storage unit 1131 of the RAM 113.

[0033] First, the CPU 111 controls the belt motor 19 using the motor drive circuit 118 to start the operation of the conveyor belt BE.

[0034] Subsequently, when the timing sensor 12 detects the arrival of the object to be printed OB based on a signal from the sensor circuit 116 (ACT1), the CPU 111 calculates the timing at which the object to be printed OB passes through each process position: erase, print, and read. This is done, for example, as follows: First, the CPU 111 calculates the transport speed of the object to be printed OB by the transport belt BE based on the rotation speed of the belt motor 19, and stores the calculated transport speed in the RAM 113. The CPU 111 also stores the time when the timing sensor 12 detected the arrival of the object to be printed OB in the RAM 113 to use that time as the reference time. Then, the CPU 111 reads the distance from the timing sensor 12 to the heater 14, printer 15, and barcode reader 16 of each process, which are non-volatilely stored in the ROM 112 or storage 114, and calculates the time from the moment the object to be printed OB reached the timing sensor 12 to each process position by dividing each distance by the transport speed. The CPU 111 stores the calculated timing for passing through each process position in the RAM 113.

[0035] Subsequently, the CPU 111 determines whether or not the label LA, i.e., the printing position, on the object OB is confirmed by using known image processing from the image signal of the label sensor 13 input via the sensor circuit 116, or by using the label detection signal of the label sensor 13. Confirmation of the label LA here does not simply mean the presence or absence of the label LA, but rather the detection of the distance of the label LA from the front end in the transport direction on the printing surface of the object OB, the distance from the upper end of the printing surface (for example, the distance from the surface facing the mounting surface), and the length and width dimensions. If it is determined that the label LA cannot be confirmed, the CPU 111 repeats this process.

[0036] The CPU 111 reads the print position of the next object to be printed OB from the RAM 113 and drives the motor 18 for the printer 15 using the motor drive circuit 118 to adjust the height of the printer 15. The CPU 111 reads the timing of the object to be printed OB's passage stored in the RAM 113 and prints the print information on the printer 15 using thermochromic ink at the print position in sync with the timing when the print position passes the printer 15 (ACT2). Specifically, the CPU 111 reads the first written information stored in the temporary storage unit 1131 of the RAM 113, creates print data to print that written information as characters, and also creates print data for a two-dimensional code representing the current date and time, measured by a clock (not shown), and the written information. Then, the CPU 111 supplies the created print data to the head drive circuit 117 and further supplies a print execution command in sync with the timing when the print position passes the printer 15. Subsequently, the CPU 111 deletes the read write information from the temporary storage unit 1131. The head drive circuit 117 drives the printer head 151 of the printer 15 based on the supplied print data in response to the print execution command and prints the print information on the label LA, which is the print position. If the print position of the print target object OB has print information from the previous use of the print target object OB, the CPU 111 controls the motor 18 and heater 14 for the heater 14 to apply heat to the print position before printing the print information in ACT2, and erases the print information by changing the color of the printed information, which is printed using thermochromic ink, from colored to colorless.

[0037] Next, the CPU 111 reads the printing position of the object OB on which the printing information is printed from the RAM 113, and drives the motor 18 for the barcode reader 16 with the motor drive circuit 118 to adjust the height of the barcode reader 16. Then, the CPU 111 reads the timing of the object OB passing over the printing position stored in the RAM 113, and reads the two-dimensional code in the printing information via the barcode reader 16 through the sensor circuit 116 in accordance with the timing of the printing position passing over the barcode reader 16 (ACT3). Finally, the CPU 111 determines whether or not the barcode reader 16 was able to read the two-dimensional code at the timing of the printing position passing over the printing position of the object OB (ACT4).

[0038] When the CPU 111 determines that it has successfully read the two-dimensional code (ACT4 YES), it determines that printing of the print information to the print target object OB is complete (ACT5), and transports the printed print target object OB on the transport belt BE, while simultaneously performing the erase, print, and read processes for the next print target object OB that is transported.

[0039] If the CPU determines that it cannot read the two-dimensional code (NO in ACT4), it controls the belt motor 19 to transport the printed object OB to the printer 15 via the transport belt BE as a reprinting process for the printed object OB that has already been printed. Specifically, the CPU 111 reverses the rotation of the belt motor 19 to reverse the transport direction of the transport belt BE, thereby transporting the printed object OB to the printer 15 in reverse. The CPU 111 then reads the print position of the printed object OB to be reprinted from the RAM 113 and drives the motor 18 for the printer 15 via the motor drive circuit 118 to adjust the height of the printer 15. The CPU 111 reads the timing of the passage of the printed object OB stored in the RAM 113 and, in accordance with the timing when the print position passes the printer 15, reprints the print information on the printer 15 using thermochromic ink at that print position (ACT2). Then, the process from ACT3 onwards is carried out, and in ACT4, the reprinting is repeated until the 2D code becomes readable (YES in ACT4).

[0040] The CPU 111 may, for example, record the type of object OB to be printed and the number of times the print information has been printed for each type of object OB (reprint count) in a database 1141 which acts as a storage unit, and calculate the number of print passes according to the type of object OB. Then, for subsequent printing of the object OB, the CPU may print the print information using the calculated number of print passes corresponding to the type of object OB. Alternatively, the number of print passes corresponding to the type of object OB may be stored in a database on the cloud, and other printing systems 10 may retrieve the number of print passes corresponding to the type of object OB from the database on the cloud. Furthermore, if the number of passes becomes large and exceeds a predetermined number of passes (threshold), the CPU 111 may set conditions such as increasing the ejection amount to reduce the number of passes, thereby enabling more efficient operation. The threshold and the increased ejection amount may, for example, be set in advance and stored in the storage unit.

[0041] Furthermore, for example, the CPU 111 stores a predetermined number of reprinting cycles n as a threshold value in a memory unit such as the RAM 113. Then, in ACT 4, if the print information cannot be read even after repeatedly printing the print information until the number of reprinting cycles reaches the predetermined number n, the CPU 111 may erase the print information by changing its color to make it colorless in the erasure process, and then print at the print position (ACT 2). This process is suitable when the print information cannot be read due to defects in the print information, such as misalignment of the print target object OB due to transport, rather than due to readability issues caused by color changes, because it involves reprinting the print information at the previously unprinted print position.

[0042] As described above, the printing system 10 according to this embodiment can print printed information on top of other information by printing again at the printing position if the printed information printed at the printing position cannot be read by the barcode reader 16, which acts as a reading unit for reading printed information. Therefore, even if the printing system 10 prints printed information using ink with low color development, the color development improves with each reprint, making it possible to read the printed information. By reprinting the printed information, the printing system 10 can read the printed information regardless of the type of media.

[0043] The printing system 10 is not limited to the examples described above. For example, in the examples described above, a transport belt BE was used as the transport unit for transporting the media, but the transport unit is not limited to the transport belt BE. Also, the printing target object OB, which is the media, was described as a box-shaped container, but it may also be packaging such as an envelope or a recording medium such as paper media. For this reason, the printing system 10 may be a recording device having an inkjet head, or it may be a finisher used in a recording device. Furthermore, in the examples described above, the printing target object OB was transported by a transport belt BE as the transport unit, but it is not limited to this, and it is sufficient as long as the printing target object OB and the heater 14, printer 15, barcode reader 16, etc. can move relative to each other by the transport unit. For example, the heating unit may transport the heater 14, printer 15, barcode reader 16, etc. without transporting the printing target object OB, and each of the printing target object OB, heating unit 14, printer 15, and barcode reader 16, etc. may be able to move to a processing position.

[0044] Furthermore, in the example described above, a timing sensor 12 and a label sensor 13 were used as the detection unit for detecting the media, but the system is not limited to this. Any sensor capable of detecting the media may be used as the detection unit. Also, in the example described above, the control unit 11 controls each operation timing based on the time when the timing sensor 12 detects the arrival of the object to be printed OB, and based on the movement speed of the object to be printed OB by the conveyor belt BE, but the system is not limited to this.

[0045] Furthermore, in the example described above, a label LA of a different color from the object to be printed OB is affixed to one surface of the object to be printed OB, and the label LA itself or a mark provided on the label LA constitutes a guide section that guides the printing position. However, the guide section may be composed of something other than the label LA. For example, the guide section may be printed on the outer surface of the object to be printed OB without a label. As a specific example, the guide section may be a registration mark (trim mark) or the like printed directly on the outer surface of the object to be printed OB. Such registration marks may be printed with thermochromic ink, or with ink other than thermochromic ink. For example, by printing registration marks with thermochromic ink, they can be erased later. Note that the guide section provided on the object to be printed OB without a label is not limited to registration marks, and its shape, including patterns and printing areas, and the type of ink are not limited, as long as it can perform the function of preventing misalignment of the printing position.

[0046] Furthermore, although the printing system 10 described above is configured to include a printer 15 equipped with color-changing ink and a barcode reader 16, the number of printers 15 and barcode readers 16 may be multiple. In the case of a configuration with multiple printers 15 and barcode readers 16, for example, the height of the multiple printers 15 and multiple barcode readers 16 may be adjustable to match the printing position, and at least one of the multiple printers 15 and multiple barcode readers 16 may be pre-set to a height corresponding to the media so as to cover the size of a typical corrugated cardboard box such as a line head. In addition, the printing system 10 may be configured to include multiple label sensors 13 and heaters 14, with adjustable heights, or at least one of them may be pre-set to a height corresponding to the media.

[0047] According to the printing system described above, if the printed information cannot be read, the transport unit moves the printing unit and media relatively, and the printed information can be read by reprinting.

[0048] While several embodiments of the present invention have been described, these embodiments are presented as examples only and are not intended to limit the scope of the invention. These novel embodiments can be carried out in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their variations are included in the scope and spirit of the invention, as well as in the claims and their equivalents. [Explanation of Symbols]

[0049] 10...Printing system, 11...Control unit, 12...Timing sensor, 13...Label sensor, 14...Heater, 15...Printer, 16...Barcode reader, 17...User interface, 18...Motor, 19...Belt motor, 20...Press motor, 114...Storage, 115...Interface, 116...Sensor circuit, 117...Head drive circuit, 118...Motor drive circuit, 119...Bus, 151...Printer head, 1131...Temporary storage unit, 1141...Database, ACT2...Printing, ACT5...Printing complete, BE...Conveyor belt, BP...Plate, LA...Label, n...Number of times, OB...Print target, PO...Support column, PP...Press plate.

Claims

1. A printing unit that prints information onto media using low-color ink, A detection unit for detecting the aforementioned media, A reading unit reads the printed information printed on the media detected by the detection unit, A transport unit that transports the media, the printing unit, the detection unit, and the reading unit relative to each other, If the reading unit cannot read the printed information on the media, the printing unit overlays and reprints the printed information on the media. A printing system equipped with [a specific feature].

2. The printing system according to claim 1, wherein the media has a guide portion for guiding the printing position.

3. The printing system according to claim 1, wherein the low-color ink is a thermochromic ink that changes color with temperature.

4. The aforementioned thermochromic ink changes color between colored and colorless. The printing system according to claim 3, wherein the control unit makes the printed information colorless when the number of reprints exceeds a predetermined number.

5. The printing system according to claim 1, wherein the control unit stores the number of times the print information is reprinted for each type of media in a storage unit, calculates the number of print passes according to the type of media, and prints on the next media to be printed using the calculated number of print passes.

Images