Printing device

Abstract

To provide a printing device that can determine whether an attached ink ribbon is a regular product or not.SOLUTION: A printing device according to an embodiment comprises an attachment part, a reading part and a determining part. An ink ribbon, which is provided with a wireless tag storing a digital certificate generated based on a secret key and a unique ID of the wireless tag using an encryption algorithm, is attached to the attachment part. The reading part makes communication with the wireless tag to read out the unique ID of the wireless tag and also read out the digital certificate stored in the wireless tag. The determining part determines whether the ink ribbon is a regular product or not, by verifying the digital certificate on the basis of a public key and the unique ID read out from the wireless tag.SELECTED DRAWING: Figure 11

Description

[Technical field]

[0001] An embodiment of the present invention relates to a printing device that uses an ink ribbon. [Background technology]

[0002] For example, a label printer transports a long piece of label paper with an ink ribbon overlapping it, transfers the ink from the ink ribbon to the label paper using a thermal head, and prints various types of information, such as barcodes, on each label on the label paper.

[0003] Label printers change their print speed depending on the type of ink ribbon used. Conventionally, there is a technology that attaches a wireless tag to the ribbon roll around which the ink ribbon is wound, and communicates data between the printer body and the wireless tag. Using this technology, the print speed of the printer body can be automatically set to a speed that matches the ink ribbon of the ribbon roll newly installed in the printer body.

[0004] On the other hand, in printers that use ribbon cartridges containing an ink ribbon, as a measure against inferior or pirated cartridges, a wireless tag is attached to the ribbon cartridge and the information stored in this wireless tag is used to identify whether it is a genuine product, such as a genuine or recommended product. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2008-030436 A Summary of the Invention [Problem to be solved by the invention]

[0006] The problem that the present invention aims to solve is to provide a printing device that uses a ribbon roll on which an ink ribbon is wound, and that is capable of determining whether the installed ink ribbon is genuine or not. [Means for solving the problem]

[0007] A printing device according to an embodiment includes an attachment unit, a reading unit, and a determination unit. An ink ribbon having a wireless tag storing a digital certificate generated using an encryption algorithm based on a private key and the wireless tag's unique ID is attached to the attachment unit. The reading unit communicates with the wireless tag to read the wireless tag's unique ID and the digital certificate stored in the wireless tag. The determination unit verifies the digital certificate based on the public key and the unique ID read from the wireless tag to determine whether the ink ribbon is genuine. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic diagram showing a label printer according to a first embodiment. [Diagram 2] FIG. 2 is a partially enlarged perspective view showing a main portion of the delivery shaft of the label printer of FIG. [Diagram 3] FIG. 3 is an exploded perspective view of the delivery shaft of FIG. [Figure 4] FIG. 4 is a cross-sectional view of a main part of the delivery shaft of FIG. [Diagram 5] FIG. 5 is a perspective view showing a paper core of a ribbon roll to be attached to the delivery shaft of FIG. [Figure 6] FIG. 6 is a block diagram of a control system of the label printer of FIG. [Figure 7] FIG. 7 is a flowchart for explaining an example of a ribbon roll manufacturing process at an ink ribbon manufacturer in the first embodiment. [Figure 8] FIG. 8 is a schematic diagram showing an overview of the genuine product determination operation in the first embodiment. [Figure 9] FIG. 9 is a flowchart showing an example of a genuine product determination process performed by the control unit in FIG. [Figure 10] FIG. 10 is a flowchart showing an example of the ribbon end process by the control unit of FIG. [Figure 11] FIG. 11 is a schematic diagram showing an overview of the genuine product determination operation in the second embodiment. [Figure 12] FIG. 12 is a flowchart for explaining an example of a ribbon roll manufacturing process at an ink ribbon manufacturer in the second embodiment. [Figure 13] FIG. 13 is a flowchart showing an example of genuine product determination processing by the control unit in the label printer according to the second embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, an embodiment will be described with reference to the drawings. Note that the scale of each part of the drawings used in the following description may be changed as appropriate. Also, the drawings may be simplified or omitted to make the description easier to understand.

[0010] [First embodiment] A label printer 100 according to a first embodiment will be described below with reference to Figures 1 to 10. The label printer 100 is an example of a printing device as defined in the claims of the present application.

[0011] FIG. 1 is a schematic diagram showing a label printer 100 according to a first embodiment. As shown in FIG. 1, the label printer 100 has a housing 2 and a cover 4. The cover 4 is rotatably connected to the housing 2 via two hinges 3. The cover 4 is rotatable between an open position shown in FIG. 1, which opens the inside of the housing 2, and a closed position, which covers the inside of the housing 2. Between the cover 4 and the housing 2, there is a damper 1 for easing the opening and closing operation of the cover 4. With the cover 4 closed, the label printer 100 has an outer shape of a substantially rectangular block.

[0012] The front surface of the housing 2 is provided with an operation unit 202, a display unit 204, and a power switch 206. The operation unit 202 is used to input information related to label paper, the number of copies to be printed, etc. The display unit 204 displays operation information, operation menus, and the like.

[0013] The label printer 100 has a supply shaft 6 to which a label paper roll is attached, a feed shaft 10 to which a ribbon roll consisting of an unused ink ribbon wound around a paper tube 30 (FIG. 5) is detachably attached, a winding shaft 12 to which a ribbon roll for winding up the used ink ribbon is detachably attached, and a printing unit 20. The feed shaft 10 is an example of a mounting section described in the claims of the present application.

[0014] A label paper roll is a long strip of label paper wound into a roll. Label paper is an example of a print medium, and is formed by affixing a number of labels in a line to one side of a long backing paper. The labels have an adhesive layer on the backing paper side, and are detachable from the backing paper. After being peeled off from the backing paper, the labels can be affixed to other items. A label paper roll is formed by wrapping label paper around a core material with the side of the backing paper to which the label is affixed facing inward. The print medium is not limited to label paper, and may be, for example, strip-shaped thermal paper.

[0015] The ribbon roll is a long ink ribbon wound into a roll. The ink ribbon holds the ink to be transferred to label paper by heat. The ribbon roll before use is the ink ribbon before the ink is transferred, wound around a paper tube 30, which is an example of a cylindrical body, and its diameter becomes smaller with use. The ribbon roll after use is the ink ribbon wound up after the ink has been transferred, and its diameter gradually becomes larger. In other words, the ink ribbon pulled out from the ribbon roll before use is wound up downstream of the printing unit 20 to become the ribbon roll after use.

[0016] The side wall 201 of the housing 2 fixes one end of the supply shaft 6, the delivery shaft 10, and the take-up shaft 12. In other words, the side wall 201 holds the three shafts 6, 10, and 12 in a cantilevered state. The take-up shaft 12 has substantially the same structure as the delivery shaft 10, except that it does not include an antenna 40 (FIGS. 2 and 3), which will be described later. Therefore, in the following description, a detailed description of the take-up shaft 12 will be omitted.

[0017] The supply shaft 6 is provided with two hold plates 701, 702 near both ends in the longitudinal direction, which respectively abut against both end surfaces in the axial direction of the label paper roll. The hold plate 701 on the far side, closer to the side wall 201, is movable along the longitudinal direction of the supply shaft 6. The hold plate 701 determines the axial attachment position of the label paper roll so that the axial center of the label paper roll is aligned with the center of the label printer 100. The hold plate 702 on the near side, which is attached near the end of the supply shaft 6 away from the side wall 201 of the housing 2, is fixed to the supply shaft 6 by a fixture 703.

[0018] When attaching the label paper roll to the supply shaft 6, the front hold plate 702 is removed from the supply shaft 6, and the label paper roll is then attached to the supply shaft 6. The front hold plate 702 is then attached to the front end of the supply shaft 6. The label paper of the label paper roll is pulled out of the label paper roll by the transport rollers 68 (FIG. 6), passes through the printing unit 20, and exits the label printer 100.

[0019] The ribbon roll delivery shaft 10 and take-up shaft 12 each include stopper plates 13, 14 near the side wall 201 of the housing 2. The stopper plates 13, 14 are movable along the longitudinal direction of the respective shafts 10, 12. The stopper plate 13 abuts against one axial end of an unused ribbon roll attached to the delivery shaft 10, and aligns the axial center of the ribbon roll with the center of the label printer 100. The stopper plate 14 abuts against one axial end of a used ribbon roll attached to the take-up shaft 12, and aligns the axial center of the ribbon roll with the center of the label printer 100.

[0020] A ribbon shaft fixing plate 15 is located at a position facing the front ends of the feed shaft 10 and the take-up shaft 12, which are away from the side wall 201. The ribbon shaft fixing plate 15 is rotatably connected via a hinge 16 to a support plate 203 that stands upward from the bottom wall 205 of the housing 2. The ribbon shaft fixing plate 15 has a receiving hole 151 that receives a tip 411 of a fixed shaft 41 (described later) of the feed shaft 10 (hereinafter, may be simply referred to as the tip 411 of the feed shaft 10), and a receiving hole 152 that receives the tip 121 of the take-up shaft 12. The ribbon shaft fixing plate 15 has an insertion hole 153 through which the head lever 21 of the printing unit 20 is inserted.

[0021] When attaching a ribbon roll to the let-off shaft 10, the ribbon shaft fixing plate 15 is opened to a position not shown, and the ribbon roll is attached to the let-off shaft 10. After that, the ribbon shaft fixing plate 15 is rotated to the position shown, and the tip 411 of the let-off shaft 10 is inserted into the receiving hole 151, and the tip 121 of the take-up shaft 12 is inserted into the receiving hole 152. In this state, the ribbon shaft fixing plate 15 fixes the tip 411 of the let-off shaft 10 and the tip 121 of the take-up shaft 12.

[0022] The ink ribbon is pulled out from a ribbon roll attached to a delivery shaft 10, passes through a printing unit 20, and is taken up by a take-up shaft 12. The printing unit 20 transports the ink ribbon, superimposed on the label paper, and passes through the printing unit 20 at the same speed as the label paper.

[0023] The printing unit 20 has a thermal head arranged on the opposite side of the ink ribbon to the label paper. The printing unit 20 has a platen roller located opposite the thermal head, sandwiching the ink ribbon and label paper between them. The printing unit 20 presses the ink ribbon against the label paper using the thermal head, thermally transferring the ink from the ink ribbon to the label paper. The printing unit 20 prints two-dimensional barcodes and the like on the labels of the label paper.

[0024] Fig. 2 is a partially enlarged perspective view showing a main part of the feed shaft 10 of the label printer 100. Fig. 3 is an exploded perspective view of the feed shaft 10. As shown in Figs. 2 and 3, the feed shaft 10 has a fixed shaft 41 fixed in a cantilever state to the side wall 201 of the housing 2, an intermediate sleeve 42 arranged coaxially on the outside of the fixed shaft 41, and a bearing 43 arranged coaxially on the outside of the fixed shaft 41.

[0025] The fixed shaft 41 is, for example, a solid metal shaft, and is fixed in a cantilever state to the side wall 201 of the housing 2 using a bolt. A tip 411 of the fixed shaft 41 protrudes from the front end of the intermediate sleeve .

[0026] The intermediate sleeve 42 is substantially cylindrical and includes a bearing 43 therein near the end on the side wall 201 side. The bearing 43 is fitted into the inside of the end of the intermediate sleeve 42 and fixed to the intermediate sleeve 42. The bearing 43 is cylindrical and can be made of resin or metal. The inner diameter of the intermediate sleeve 42 is substantially the same as the outer diameter of the bearing 43.

[0027] The intermediate sleeve 42 is rotatable relative to the fixed shaft 41 by means of a bearing 43. The intermediate sleeve 42 is provided with the above-mentioned stopper plate 13 on the outside near the end on the side wall 201 side. The stopper plate 13 is movable in the longitudinal direction of the intermediate sleeve 42, and can be fixed at a desired position in the longitudinal direction.

[0028] The outer peripheral surface of the intermediate sleeve 42 has two bosses 421 for positioning the leaf spring 44 and screw holes 422 for fastening and fixing the leaf spring 44 to the outer peripheral surface of the intermediate sleeve 42. The leaf spring 44 has a slit 441 at one end on the side wall 201 side through which the bosses 421 are inserted, and a screw hole at the other end through which a screw 442 is inserted. The leaf spring 44 is fixed to the outer peripheral surface of the intermediate sleeve 42 by inserting the bosses 421 of the intermediate sleeve 42 into the slits 441 and screwing the screws 442 into the screw holes 422.

[0029] The leaf spring 44 is made of metal, and with the cardboard tube 30 of the ribbon roll attached to the outside of the intermediate sleeve 42, it presses the inner surface of the cardboard tube 30 outward to fix the cardboard tube 30 to the intermediate sleeve 42. The leaf spring 44 protrudes from the outer circumferential surface of the intermediate sleeve 42 to an extent that the intermediate sleeve 42 can be inserted into the cardboard tube 30. The leaf spring 44 has a circumferential width narrower than the width of the antenna 40 along the circumferential direction of the fixed shaft 41.

[0030] A sheet-like antenna 40 is provided on the outer peripheral surface of the fixed shaft 41. A wiring 401 is provided on the outer peripheral surface of the fixed shaft 41, electrically connected to the antenna 40 and extending in the longitudinal direction of the fixed shaft 41. The antenna 40 and the wiring 401 are, for example, continuous metal foil, and may be a metal foil patterned on the surface of a flexible substrate. For example, the pattern of the antenna 40 is in the shape of a loop antenna to generate a magnetic field.

[0031] There is a magnetic sheet 45 between the outer circumferential surface of the fixed shaft 41 and the antenna 40. The magnetic sheet 45 is provided so that the magnetic field generated by the antenna 40 does not cause eddy currents to be generated in the metallic fixed shaft 41, thereby preventing the magnetic field generated by the antenna 40 from being cancelled out. For this reason, the magnetic sheet 45 has a size slightly larger than the antenna 40 so that it is present between the antenna 40 and the fixed shaft 41.

[0032] Since antenna 40 is separated from the outer circumferential surface of fixed shaft 41 by the thickness of magnetic sheet 45, the end of wiring 401 on the antenna 40 side is slightly inclined in a direction away from the outer circumferential surface of fixed shaft 41 towards antenna 40. Since bearing 43 is provided between intermediate sleeve 42 and fixed shaft 41, the inner diameter of intermediate sleeve 42 is sufficiently larger than the outer diameter of fixed shaft 41. For this reason, when fixed shaft 41 is inserted into intermediate sleeve 42 or when intermediate sleeve 42 rotates relative to fixed shaft 41, the inner surface of intermediate sleeve 42 does not come into sliding contact with antenna 40 and wiring 401.

[0033] 4 is a cross-sectional view of a main part of the delivery shaft 10. As shown in FIGS. 2 and 4, the fixed shaft 41 has a groove-shaped recess 412 provided on its outer circumferential surface along the longitudinal direction. The width of the recess 412 along the circumferential direction of the fixed shaft 41 is slightly wider than the width of the wiring 401. The depth of the recess 412 is slightly deeper than the thickness of the wiring 401. The antenna 40 is attached by bonding the magnetic sheet 45 to the outer circumferential surface of the fixed shaft 41, and then overlapping and attaching the magnetic sheet 45.

[0034] A protective sleeve 50 is located near the end of the fixed shaft 41 on the side wall 201 side. The inner diameter of the protective sleeve 50 is approximately the same as the outer diameter of the fixed shaft 41, and the outer diameter is slightly smaller than the inner diameter of the bearing 43. In other words, there is a gap between the intermediate sleeve 42 and the fixed shaft 41 that is the thickness of the protective sleeve 50. The protective sleeve 50 is interposed between the wiring 401 and the bearing 43, and is fitted and fixed to the end of the fixed shaft 41.

[0035] When the fixed shaft 41 with the protective sleeve 50 fixed thereto is inserted into the intermediate sleeve 42 with the bearing 43 fitted at one end thereof, and the intermediate sleeve 42 is attached to the fixed shaft 41, the inner peripheral surface of the bearing 43 comes into contact with the outer peripheral surface of the protective sleeve 50. Since the inner diameter of the bearing 43 is slightly larger than the outer diameter of the protective sleeve 50 and there is a small gap between the two, the intermediate sleeve 42 with the bearing 43 is rotatable relative to the fixed shaft 41 with the protective sleeve 50. The protective sleeve 50 prevents the intermediate sleeve 42 from sliding against the wiring 401 housed and arranged in the recess 412 of the fixed shaft 41 when the intermediate sleeve 42 rotates relative to the fixed shaft 41.

[0036] FIG. 5 is a perspective view showing the cardboard tube 30 of the ribbon roll to be attached to the delivery shaft 10. As shown in FIG. 5, the cardboard tube 30 of the ribbon roll to be attached to the delivery shaft 10 has an IC tag 32 that communicates wirelessly. The IC tag 32 is a rectangular sheet, and is attached to the outer circumferential surface 301 of the cardboard tube 30 by adhesive at approximately the center in the axial direction of the cardboard tube 30. The ink ribbon is wrapped around the outer circumferential surface of the cardboard tube 30, overlapping the outside of the IC tag 32. The IC tag 32 may be provided on the cardboard tube 30, and may be provided on the inner surface of the cardboard tube 30 or on an intermediate portion between the outer circumferential surfaces and the inner surface of the cardboard tube 30. The IC tag is an example of a wireless tag described in the claims of this application.

[0037] Fig. 6 is a block diagram showing an example of a control system of the label printer 100. As shown in Fig. 6, the label printer 100 has a control unit 60 that sets the print speed depending on the type of ink ribbon. The control unit 60 is configured with a processor such as a CPU (Central Processing Unit). The processor may be, for example, an MPU (Micro Processing Unit), an SoC (System on a Chip), a DSP (Digital Signal Processor), a GPU (Graphics Processing Unit), an ASIC (Application Specific Integrated Circuit), a PLD (Programmable Logic Device), or an FPGA (Field-Programmable Gate Array). Alternatively, the processor may be a combination of two or more of these.

[0038] The control unit 60 is connected to a power switch 206 , an operation unit 202 , a display unit 204 , a memory 62 , a reader / writer 63 , motors 64 and 65 , and a communication unit 67 .

[0039] The memory 62 stores a control program, and also stores data related to the print speed suitable for the type of ink ribbon. Furthermore, the memory 62 includes a public key memory 621 that stores a public key. The public key is provided by the ribbon manufacturer that produces the ribbon roll, and can be stored in the public key memory 621 when the label printer 100 is manufactured. In other words, the label printer 100 can store the public key in advance.

[0040] The reader / writer 63 wirelessly communicates with the IC tag 32 via the antenna 40, writing data to the IC tag 32 and reading data from the IC tag 32. A motor 64 rotates a transport roller 68 that pulls out the label paper from the label paper roll. A motor 65 rotates a transport roller 69 that transports the ink ribbon.

[0041] The communication unit 67 transmits and receives various data to and from an external device 70 such as a host computer via a network or directly. The communication unit 67 may be a wireless communication unit or a wired communication unit. The data received from the external device 70 includes print data. The external device 70 may include a server provided in a cloud. The data received from the server includes a public key. That is, when the ribbon manufacturer updates the public key or releases a new public key with the release of a new product, the label printer 100 can receive the public key from the server and update the public key stored in the public key memory 621. The label printer 100 may be provided with an interface with a removable storage medium such as a USB memory, and may read the public key from the storage medium and store it in the public key memory 621.

[0042] When the power switch 206 is turned ON, the control unit 60 controls the reader / writer 63 to read data from the IC tag 32 via the antenna 40. In particular, the label printer 100 is designed such that when replacing the ribbon roll on the feed shaft 10, the cover 4 of the housing 2 cannot be opened to replace the ribbon roll, or it is recommended to turn the power switch 206 OFF before replacing the ribbon roll. Therefore, in many cases, when using the label printer 100 after replacing the ribbon roll on the feed shaft 10, the power switch 206 is turned ON, and data is read from the IC tag 32 at that time. Alternatively, the number of times the cover 4 is opened and closed may be stored in a non-volatile manner in the memory 62, and an open / close counter that mechanically counts the number of times the cover 4 is opened and closed and the count value can be read by the control unit 60. In this way, the control unit 60 does not read data from the IC tag 32 every time the power switch 206 is turned ON, but only reads data from the IC tag 32 when the count value of the open / close counter is different from the number of times the cover 4 is opened and closed stored in the memory 62.

[0043] The IC tag 32 stores a unique identifier (UID) for uniquely identifying each IC tag in a non-rewritable manner. The UID is an example of a unique ID described in the claims of the present application. The IC tag 32 also stores data related to the ink ribbon wound around the paper tube 30. The data related to the ink ribbon includes, for example, the product name, grade, dimensions, color, date of manufacture, serial number, etc. The grade indicates the type of ink ribbon, for example, for plain paper or for thick paper. The dimensions are the width and length of the ink ribbon, and the length may be said to be the amount of ink ribbon. The serial number may be a manufacturing number. The data related to the ink ribbon is an example of the ribbon data described in the claims of the present application. Furthermore, the IC tag 32 stores a digital certificate that is generated based on a private key, a UID, and the ribbon data using an encryption algorithm. The digital certificate is an example of the digital certificate described in the claims of the present application.

[0044] Therefore, the control unit 60 reads the UID, ribbon data, and digital certificate as data from the IC tag 32. The reader / writer 63 and the antenna 40 are an example of a reading unit as described in the claims of the present application. After that, the control unit 60 verifies the digital certificate based on the public key and UID stored in the public key memory 621, thereby determining whether the ink ribbon having the IC tag 32 is genuine or not. Therefore, the control unit 60 is an example of a determination unit as described in the claims of the present application.

[0045] If the ink ribbon is genuine, the control unit 60 reads from the memory 62 the print speed that matches the type of ink ribbon in the ribbon data read from the IC tag 32, and controls the motors 64, 65 to print at this print speed. The control unit 60 controls the motors 64, 65 to print at this print speed until the ink ribbon is used up. When the ink ribbon is used up, the control unit 60 controls the reader / writer 63 to erase the digital certificate stored in the IC tag 32. Thus, the control unit 60 is an example of the erasing unit described in the claims of this application. Note that "erasing" does not mean simple erasing such as deleting part of data, but complete erasing that cannot be restored. This "erasing" also includes rewriting the data to different information, such as changing all data to "0" or all data to "1", that is, destroying the original information.

[0046] As described above, in the label printer 100 according to this embodiment, the antenna 40 is provided on the delivery shaft 10 to which the ribbon roll in which the ink ribbon is wound around the cardboard tube 30 is attached. This allows the antenna 40 to be positioned close to the IC tag 32 affixed to the cardboard tube 30, enabling good data communication between the antenna 40 and the IC tag 32.

[0047] The genuine product determination operation in the first embodiment will be described below with reference to Figs. 7 to 9. Fig. 7 is a flow chart for explaining an example of a ribbon roll manufacturing process at the ink ribbon manufacturer MC. Fig. 8 is a schematic diagram showing an overview of the genuine product determination operation. Fig. 9 is a flow chart showing an example of genuine product determination processing by the control unit 60 of the label printer 100. Note that the manufacturing process at the ink ribbon manufacturer MC may be performed by one machine or multiple machines, or may even involve manual intervention. In other words, it does not matter who performs each process.

[0048] In the ink ribbon manufacturer MC, as shown in FIGS. 7 and 8, first, in a step PRO11, the UID 81 is read from the IC tag 32.

[0049] Also, in step PRO12, ribbon data 82 to be written to the IC tag 32 is obtained. Here, the ribbon data may be obtained by any method, such as input from an operating member such as a keyboard, reading from a storage medium, or communication from an external device.

[0050] In step PRO13, the UID 81 and ribbon data 82 are hashed. Hashing is a process that uses an algorithm called a hash function to convert data into an irregular character string to obtain a hash value. Since the hash value converted from the same data always results in the same result, the data cannot be restored after conversion.

[0051] In step PRO14, a digital certificate 84 is created based on the private key 83 and the hash value using an encryption algorithm. This can also be said to create the digital certificate 84 based on the private key 83, UID 81, and ribbon data 82 using an encryption algorithm. The private key 83 is strictly managed so as not to be leaked to the outside, and is only usable when creating this digital certificate 84. There are no particular limitations on the encryption algorithm, but for example, well-known RSA encryption or elliptic curve encryption can be used. Elliptic curve encryption produces smaller data than RSA encryption, and is therefore suitable for IC tags 32 with only limited storage capacity.

[0052] In step PRO15, the created digital certificate 84 and ribbon data 82 are written to the IC tag 32. In this way, a genuine IC tag 32 to be affixed to the paper core 30 of the ribbon roll is completed (hereinafter, such a genuine IC tag 32 may be referred to as a genuine IC tag 321).

[0053] Then, in step PRO16, the genuine product IC tag 321 with the digital certificate 84 and ribbon data 82 written therein is affixed to the paper tube 30.

[0054] In the next process, an ink ribbon is wound around the paper tube 30 with the IC tag 32 thus produced, completing a genuine ribbon roll before use.

[0055] In the label printer 100, when the genuine ribbon roll completed by the ink ribbon manufacturer MC in this manner is loaded and the power switch 206 is turned ON, the control unit 60 starts the processing shown in Fig. 9 based on the control program stored in the memory 62. Unless otherwise specified, the processing operation of the control unit 60 transitions from ACTx (x is a natural number) to ACT(x+1).

[0056] As shown in Figures 8 and 9, in ACT11, the control unit 60 controls the reader / writer 63 to read the UID, which is non-rewritably stored, and the ribbon data 82, which is rewritable or non-rewritable stored, from the IC tag 32 affixed to the paper core 30 of the installed ribbon roll.

[0057] In ACT12, the control unit 60 hashes the read UID 81 and ribbon data 82. The hash value obtained in this way is the same as the hash value obtained in step PRO13 at the ink ribbon manufacturer MC.

[0058] In ACT 13 , the control unit 60 controls the reader / writer 63 to read the digital certificate 84 from the IC tag 32 .

[0059] In ACT14, the control unit 60 decrypts the digital certificate 84 by a decryption algorithm corresponding to the encryption algorithm used in the process PRO14 at the ink ribbon manufacturer MC, using the public key 85 stored in the public key memory 621. This provides the hash values ​​of the UID 81 and ribbon data 82 hashed in the process PRO13 at the ink ribbon manufacturer MC.

[0060] In ACT15, the control unit 60 verifies the digital certificate 84 based on the UID 81 and the ribbon data 82. Specifically, the control unit 60 compares the hash values ​​of the UID 81 and the ribbon data 82 derived from the digital certificate 84 decrypted in ACT14 with the hash values ​​of the UID 81 and the ribbon data 82 derived from the IC tag 32 acquired in ACT12.

[0061] In ACT16, the control unit 60 determines whether or not the two hash values ​​match. In the genuine IC tag 321, the UID 81 on which the digital certificate 84 is based matches the UID stored in the IC tag 32 in a non-rewritable manner. Also, the ribbon data 82 on which the digital certificate 84 is based matches the ribbon data 82 stored in the IC tag 32. Therefore, their hash values ​​also match.

[0062] If it is determined that the two hash values ​​match (True) (ACT16, YES), the control unit 60 determines in ACT17 that the installed ribbon roll is genuine and permits printing. Then, the operation of this genuine product determination process ends.

[0063] Thereafter, the control unit 60 reads from the memory 62 a print speed that matches the type of ink ribbon in the ribbon data 82 read from the IC tag 32, and controls the motors 64, 65 to print at this print speed. The control unit 60 controls the motors 64, 65 to print at this print speed until the ink ribbon is used up.

[0064] There are also label printers that perform processes such as rewriting the remaining amount of ink ribbon in the ribbon data stored in the IC tag 32 when each print task ends. In this embodiment, the ribbon data 82 is used to verify the digital certificate 84, so the control unit 60 does not perform such processes.

[0065] Also, as shown in FIG. 8, a third party may copy data stored in the genuine IC tag 321 of a ribbon roll completed by the ink ribbon manufacturer MC to create a counterfeit IC tag 32 (hereinafter, such a counterfeit IC tag 32 may be referred to as a counterfeit IC tag 322). In this case, the counterfeit IC tag 322 stores a digital certificate 84 and ribbon data 82. A third party can use this counterfeit IC tag 322 to manufacture counterfeit ribbon rolls. However, since the UID cannot be rewritten in the counterfeit IC tag 322, a UID different from that of the genuine IC tag 321 is stored. In the example of FIG. 8, the UID of the genuine IC tag 321 is "E007000030928675", whereas the UID of the counterfeit IC tag 322 is "E007000030920000".

[0066] Even when such a counterfeit ribbon roll is installed, the control unit 60 of the label printer 100 executes the above-mentioned ACT11 to ACT16 in the same manner as when a genuine ribbon roll is installed. The UID of the counterfeit IC tag 322 is different from the UID of the genuine IC tag 321. Therefore, although the ribbon data 82 on which the digital certificate 84 is based matches the ribbon data 82 stored in the IC tag 32, the UID 81 on which the digital certificate 84 is based does not match the UID stored in the IC tag 32 in a non-rewritable manner. Therefore, the hash value of the UID 81 and ribbon data 82 derived from the digital certificate 84 decrypted in the above ACT14 does not match the hash value of the UID 81 and ribbon data 82 derived from the counterfeit IC tag 322 acquired in the above ACT12.

[0067] If it is determined that the two hash values ​​do not match (False) (ACT16, NO), the control unit 60 determines in ACT18 that the attached ribbon roll is not a genuine product and prohibits printing.

[0068] In ACT19, the control unit 60 displays on the display unit 204 that a counterfeit product, i.e., a non-genuine product, has been attached, and then ends the operation of this genuine product determination process.

[0069] Next, the operation at the time of ribbon end in the first embodiment will be described with reference to Fig. 10. Fig. 10 is a flow chart showing an example of ribbon end processing by the control unit 60. When a print task is started, the control unit 60 starts the processing shown in Fig. 10 based on the control program stored in the memory 62.

[0070] In ACT101, the control unit 60 judges whether the ribbon end has been detected, that is, whether the ink ribbon of the attached ribbon roll has been used up. The method of detecting the ribbon end is not limited. For example, a plurality of reflective photosensors are arranged in a row at regular intervals on the side wall 201 of the label printer 100 so as to face the ribbon roll attached to the delivery shaft 10, and the remaining amount of ink ribbon is detected, and the ribbon end is detected by one of the plurality of reflective photosensors. Alternatively, a rotating body such as a roller that contacts the ink ribbon is provided on the transport path of the ink ribbon, and the ribbon end can be detected when the ink ribbon is not transported even when the transport roller 69 is rotated by the motor 65.

[0071] In response to the determination that the ribbon end has not been detected (ACT101, NO), the control unit 60 determines in ACT102 whether or not the print task has ended. In response to the determination that the print task has ended (ACT102, YES), the control unit 60 ends the ribbon end processing operation. In addition, in response to the determination that the print task has not yet ended (ACT102, NO), the control unit 60 proceeds to the processing of ACT101.

[0072] In response to the determination that the ribbon end has been detected (ACT101, YES), the control unit 60 erases at least the digital certificate 84 stored in the IC tag 32 in ACT103. After that, the control unit 60 proceeds to the process of ACT102.

[0073] In the first embodiment, the UID 81 and the ribbon data 82 are hashed, but they do not necessarily have to be hashed. That is, the ink ribbon manufacturer MC creates a digital certificate 84 using the raw data of the UID 81 and the ribbon data 82, and the control unit 60 of the label printer 100 also verifies the digital certificate 84 by comparing the raw data of the UID 81 and the ribbon data 82 read from the IC tag 32 with the UID 81 and the ribbon data 82 decrypted from the digital certificate 84.

[0074] As described above, in the label printer 100 according to the first embodiment, an ink ribbon having an IC tag 32 in which the ribbon data 82 and the digital certificate 84 generated using an encryption algorithm based on a private key and the UID 81 and ribbon data 82 of the IC tag 32 are stored is attached. Then, the control unit 60 of the label printer 100 controls the reader / writer 63 to communicate with the IC tag 32, reads the UID 81 and ribbon data 82 of the IC tag 32, and reads the digital certificate 84 stored in the IC tag 32. Then, the control unit 60 verifies the digital certificate 84 based on the public key stored in the public key memory 621 and the UID 81 and ribbon data 82 read from the IC tag 32, thereby determining whether the attached ink ribbon is genuine or not. Thus, in the label printer 100 according to the first embodiment, it is possible to determine whether the attached ink ribbon is genuine or not.

[0075] Since the UID 81 and ribbon data 82 used to generate the digital certificate 84 are hashed, in the label printer 100 according to the first embodiment, the control unit 60 hashes the UID 81 and ribbon data 82 read from the IC tag 32, and verifies the digital certificate 84 based on the hashed UID 81 and ribbon data 82 and the public key. Therefore, even if the confidentiality of the data is increased by hashing, the label printer 100 according to the first embodiment can determine whether the attached ink ribbon is genuine or not.

[0076] Furthermore, in the label printer 100 according to the first embodiment, the control unit 60 erases the digital certificate 84 stored in the IC tag 32 in response to detection of the end of the ink ribbon. This makes it possible to prevent the IC tag 32 of an ink ribbon that has run out of ink from being reused.

[0077] Although the public key stored in the public key memory 621 is previously stored, it can be updated with a public key received from the external device 70 via the communication unit 67. This makes it possible to deal with public key replacement in the event of a private key leak at the ink ribbon manufacturer MC.

[0078] The label printer 100 according to the first embodiment also includes a feed-out shaft 10 that is inserted into the paper tube 30 of a ribbon roll formed by winding an ink ribbon around the paper tube 30 equipped with an IC tag 32 and rotatably supports the ribbon roll, and an antenna 40 that is provided on the feed-out shaft 10 and that communicates data with the IC tag 32. By providing the antenna 40 on the feed-out shaft 10 that is equipped with a ribbon roll formed by winding an ink ribbon around the paper tube 30, the antenna 40 can be positioned close to the IC tag 32 affixed to the paper tube 30, enabling good data communication between the antenna 40 and the IC tag 32.

[0079] [Second embodiment] The configuration of the label printer 100 in the second embodiment is similar to that in the first embodiment, and therefore a description thereof will be omitted. Hereinafter, the operation of the label printer 100 according to the second embodiment will be described with reference to Figs. 11 to 13. Fig. 11 is a schematic diagram showing an overview of the genuine product determination operation in the second embodiment. Fig. 12 is a flowchart for explaining an example of a ribbon roll manufacturing process at the ink ribbon manufacturer MC in the second embodiment. Fig. 13 is a flowchart showing an example of genuine product determination processing by the control unit 60 in the label printer 100 according to the second embodiment.

[0080] As shown in FIGS. 11 and 12, the ink ribbon manufacturer MC reads the UID 81 and acquires ribbon data 82 in steps PRO11 and PRO12, similarly to the first embodiment.

[0081] In this embodiment, only the UID 81 is hashed in step PRO21. That is, in this embodiment, the ribbon data 82 is not hashed. Therefore, in this step PRO21, a hash value of the UID 81 is obtained.

[0082] Next, in the same manner as in the first embodiment, in step PRO14, a digital certificate 84 is created based on the private key 83 and the hash value using an encryption algorithm. However, in this embodiment, the hash value is obtained by hashing only the UID 81.

[0083] Thereafter, in steps PRO15 and PRO16, the digital certificate 84 and the ribbon data 82 are written into the IC tag 32 to complete the genuine IC tag 321, which is then attached to the cardboard tube 30, in the same manner as in the first embodiment.

[0084] In the label printer 100 according to this embodiment, the control unit 60 reads the UID and ribbon data 82 from the IC tag 32 in ACT11, as in the first embodiment, as shown in FIGS.

[0085] In this embodiment, in ACT 21, the control unit 60 hashes only the read UID 81. That is, in this embodiment, the ribbon data 82 is not hashed. Therefore, in this ACT 21, a hash value of the UID 81 is obtained.

[0086] Thereafter, in ACT13 and ACT14, the control unit 60 reads the digital certificate 84 from the IC tag 32, and decrypts the digital certificate 84 by a decryption algorithm using the public key 85 stored in the public key memory 621, as in the first embodiment. In this case, unlike the first embodiment, the obtained hash value is a hash value of only the UID 81 hashed in process PRO21 at the ink ribbon manufacturer MC.

[0087] Therefore, in this embodiment, in ACT22, the control unit 60 verifies the digital certificate 84 based on the UID 81. Specifically, the control unit 60 compares the hash value of the UID 81 derived from the digital certificate 84 decrypted in ACT14 with the hash value of the UID 81 derived from the IC tag 32 acquired in ACT21.

[0088] Then, similarly to the first embodiment, the control unit 60 determines whether or not the two hash values ​​match in ACT 16. In the genuine IC tag 321, the UID 81 on which the digital certificate 84 is based matches the UID stored in the IC tag 32 in a non-rewritable manner, and therefore the two hash values ​​match.

[0089] If it is determined that the two hash values ​​match (True) (ACT16, YES), the control unit 60 determines that the attached ribbon roll is genuine and permits printing in ACT17, as in the first embodiment. Then, the operation of this genuine product determination process ends.

[0090] After this, the control unit 60 can execute the print task.

[0091] Furthermore, in this embodiment, since the ribbon data 82 is not used for the digital certificate 84, there is no problem even if the ribbon data stored in the IC tag 32 is rewritten. Therefore, the control unit 60 can rewrite the remaining amount of ink ribbon in the ribbon data stored in the IC tag 32 at the timing when each print task ends. The control unit 60 can also display the remaining amount of ink ribbon via the display unit 204. Furthermore, when performing a process of erasing at least the digital certificate 84 stored in the IC tag 32 upon ribbon end detection as described in the first embodiment, the remaining amount of ink ribbon stored in the IC tag 32 can also be used to detect the ribbon end.

[0092] 11, if a third party copies data stored in the genuine IC tag 321 of a ribbon roll completed by the ink ribbon manufacturer MC to create a counterfeit IC tag 322, the counterfeit IC tag 322 stores the digital certificate 84 and ribbon data 82, as in the first embodiment. When a counterfeit ribbon roll using this counterfeit IC tag 322 is attached, the control unit 60 in the label printer 100 executes the above-mentioned ACT11, ACT21, ACT13, ACT14, ACT22, and ACT16 processes, as in the case where a genuine ribbon roll is attached. Since the UID of the counterfeit IC tag 322 is different from the UID of the genuine IC tag 321, the UID 81 on which the digital certificate 84 was based does not match the UID stored in the IC tag 32 in a non-rewritable manner. Therefore, the hash value of the UID 81 derived from the digital certificate 84 decrypted in ACT14 does not match the hash value of the UID 81 derived from the counterfeit IC tag 322 obtained in ACT21.

[0093] If it is determined that the two hash values ​​do not match (False) (ACT16, NO), the control unit 60, like the first embodiment, determines in ACT18 and ACT19 that the installed ribbon roll is not genuine, prohibits printing, and displays on the display unit 204 that a non-genuine product has been installed. Then, the operation of this genuine product determination process ends.

[0094] In addition, even in the second embodiment, it is not essential to hash the UID 81. That is, the ink ribbon manufacturer MC may create a digital certificate 84 using the raw data of the UID 81, and the control unit 60 of the label printer 100 may also verify the digital certificate 84 by comparing the raw data of the UID 81 read from the IC tag 32 with the UID 81 decrypted from the digital certificate 84.

[0095] As described above, in the label printer 100 according to the second embodiment, an ink ribbon having an IC tag 32 storing a digital certificate 84 generated based on a private key and the UID 81 of the IC tag 32 using an encryption algorithm is attached. Then, the control unit 60 of the label printer 100 controls the reader / writer 63 to communicate with the IC tag 32, reads the UID 81 of the IC tag 32, and reads the digital certificate 84 stored in the IC tag 32. Then, the control unit 60 verifies the digital certificate 84 based on the public key stored in the public key memory 621 and the UID 81 read from the IC tag 32, thereby determining whether the attached ink ribbon is genuine or not. Thus, in the label printer 100 according to the second embodiment, it is possible to determine whether the attached ink ribbon is genuine or not, as in the first embodiment. Furthermore, in the second embodiment, the ribbon data 82 is not used for the digital certificate 84, so that the ribbon data 82 can be rewritten.

[0096] Since the UID 81 used to generate the digital certificate 84 is hashed, in the label printer 100 according to the second embodiment, the control unit 60 hashes the UID 81 read from the IC tag 32 and verifies the digital certificate 84 based on this hashed UID 81 and the public key. Therefore, even if the confidentiality of the data is increased by hashing, it is possible to determine whether the attached ink ribbon is genuine or not.

[0097] Although the embodiment of the present invention has been described above, the above-mentioned embodiment is presented as an example and is not intended to limit the scope of the invention. The above-mentioned embodiment can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the gist of the invention. The above-mentioned embodiment and its modifications are included in the scope and gist of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0098] 10...feed shaft, 30...paper tube, 32...IC tag, 321...genuine IC tag, 322...counterfeit IC tag, 40...antenna, 60...control unit, 62...memory, 621...public key memory, 63...reader / writer, 64,65...motor, 67...communication unit, 68,69...conveyor roller, 70...external device, 81...UID, 82...ribbon data, 83...private key, 84...digital certificate, 85...public key, 100...label printer, 202...operation unit, 204...display unit, 206...power switch, MC...ink ribbon manufacturer.

Claims

1. a mounting section for mounting an ink ribbon having a wireless tag storing a digital certificate generated based on a secret key and a unique ID of the wireless tag using an encryption algorithm; a reader that communicates with the wireless tag to read the unique ID of the wireless tag and read the digital certificate stored in the wireless tag; a determination unit that determines whether the ink ribbon is genuine by verifying the digital certificate based on a public key and the unique ID read from the wireless tag; A printing device comprising:

2. the unique ID used to generate the digital certificate is hashed; The printing device according to claim 1 , wherein the determination unit hashes the unique ID read from the wireless tag, and verifies the digital certificate based on the hashed unique ID and the public key.

3. the digital certificate is generated based on the private key, the unique ID, and ribbon data related to the ink ribbon, and the wireless tag stores the digital certificate and the ribbon data; The reader further reads the ribbon data from the wireless tag, The printing device according to claim 1 , wherein the determination unit verifies the digital certificate based on the public key, the unique ID, and the ribbon data.

4. the unique ID and the ribbon data used to generate the digital certificate are hashed; The printing device according to claim 3 , wherein the determination unit hashes the unique ID and the ribbon data read from the wireless tag, and verifies the digital certificate based on the hashed unique ID and the ribbon data and the public key.

5. 5. The printing device according to claim 1, further comprising an erasing unit that erases the digital certificate stored in the wireless tag in response to detection of an end of the ink ribbon.

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