Replacement part authentication apparatus, image forming apparatus, and program

Abstract

To provide a replacement component authentication device capable of shortening the processing time of authentication processing for authenticating a replacement component, and to provide an image forming apparatus and a program.SOLUTION: The controller 30 of the printer 10 can execute, for the cartridge 100 installed in the installation case 27, the main authorization process (S11) for authorizing the cartridge 100, and the simple authorization process (S9) requiring a shorter processing time for the authorization process than the main authorization process. When the controller 30 determines that the cartridge 100 is attached to the attachment case 27 for the first time (S5: NO), the controller 30 executes the main verification process and stores the cartridge identification information 131 for the cartridge 100 (S16). Then, the controller 30 switches between the main verification process and the simple verification process at a certain probability or the like when executing the next and subsequent verification for the cartridge 100 that has succeeded in the main verification (S7).SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present specification relates to a replacement part authentication device, an image forming apparatus, and a program for authenticating an installed replacement part. [Background technology]

[0002] Various technologies for authenticating replacement parts have been proposed in the past. Patent Document 1 below describes a consumables management server that determines whether an ink cartridge installed in an inkjet printing device is a compatible product. The inkjet printing device in Patent Document 1 acquires identification information from the tag of the ink cartridge installed in the device and transmits it to the consumables management server. The consumables management server determines whether the identification information acquired by the inkjet printing device is the same as identification information previously acquired by the same inkjet printing device. If the identification information is the same, the consumables management server causes the inkjet printing device to output a signal to the ink cartridge tag to acquire response characteristics. If the response characteristics of the tag's reply signal in response to the signal satisfy preset response characteristic conditions, the consumables management server determines that the ink cartridge is a compatible product. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Patent Publication No. 2021-135835 Summary of the Invention [Problem to be solved by the invention]

[0004] In devices that perform authentication processing for replacement parts, such as the inkjet printing device described above, it is preferable to use stronger encryption techniques, such as longer encryption keys or asymmetric encryption, in order to increase the reliability of authentication. However, the more reliable the authentication, the more complex the encryption and decryption calculations become, which can increase the processing time required for authentication. As a result, there is a problem of delays in starting processing after successful authentication.

[0005] This specification has been proposed in consideration of the above-mentioned problems, and aims to provide a replacement part authentication device, an image forming device, and a program that can shorten the processing time of the authentication process for authenticating replacement parts. [Means for solving the problem]

[0006] In order to achieve the above-mentioned object, the replacement part authentication device of this specification comprises a replacement part, a mounting unit to which the replacement part can be attached and detached, and a controller, and the controller is capable of executing a main authentication process to authenticate the replacement part, and a simplified authentication process to authenticate the replacement part and to execute authentication requiring a shorter processing time than the main authentication process, and the controller executes the main authentication process for the replacement part that is being attached to the mounting unit for the first time, and when performing subsequent authentication for the replacement part that has been successfully authenticated by the main authentication process, the controller switches between the main authentication process and the simplified authentication process using at least one of a fixed probability, a predetermined timing, randomly, and a variable probability that changes the probability depending on the success of the authentication. Furthermore, the contents of this specification are not limited to implementation as a replacement part authentication device, but are also extremely useful when implemented as an image forming device equipped with a replacement part authentication device, a program executed by a computer in the replacement part authentication device, or a program stored on a computer-readable medium. [Effects of the Invention]

[0007] According to the replacement part authentication device, image forming device, and program according to the present specification, the processing time for authentication processing for authenticating a replacement part can be reduced. [Brief explanation of the drawings]

[0008] [Figure 1] 1A and 1B are external perspective views of a printer 10 according to a first embodiment, in which (A) shows a closed state with a cover 11 closed, and (B) shows an open state with the cover 11 open. [Figure 2] FIG. 1 is a schematic diagram showing the internal structure of a printer 10 according to a first embodiment. [Figure 3] FIG. 1 is a block diagram of a printer 10 according to a first embodiment. [Figure 4] FIG. 2 is a block diagram of an IC substrate 105 according to the first embodiment. [Figure 5] 10 is a flowchart of a cartridge authentication process according to the first embodiment. [Figure 6] FIG. 10 is a diagram showing a variable probability determination method 2 according to another embodiment. [Figure 7] FIG. 10 is a diagram showing a variable probability determination method 3 according to another embodiment. [Figure 8] FIG. 10 is a block diagram of a printer 10 according to a second embodiment. [Figure 9] 10 is a flowchart of a cartridge authentication process according to the second embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] (First embodiment) The following describes embodiments that embody the replacement part authentication device and image forming apparatus of this specification. Note that the embodiment described below is merely an example of the invention according to this specification, and it goes without saying that the embodiment can be modified as appropriate without departing from the spirit of this specification. FIG. 1 shows a perspective view of a printer 10 according to a first embodiment, with FIG. 1(A) showing a closed state with the cover 11 closed and FIG. 1(B) showing an open state with the cover 11 open. In the following description, the up-down direction 1, left-right direction 2, and front-rear direction 3 are defined based on the direction in which the printer 10 is viewed from the front, as shown in FIG. 1.

[0010] (Printer 10 Overview) FIG. 2 is a schematic diagram of the internal structure of printer 10. As shown in FIGS. 1 and 2, printer 10 is a device that prints images on sheets using an inkjet method, and includes a roughly rectangular parallelepiped housing 13. Inside housing 13, there are provided a paper feed tray 15, a paper feed roller 16, a transport roller 17, a head 21 having a plurality of nozzles 19, a platen 22 facing head 21, a discharge roller 23, a discharge tray 25, an attachment case 27 to / from which cartridge 100 is attached / detached, a tube 29, a controller 30 (see FIG. 3), and a drive source 31 (see FIG. 3). Tube 29 connects a connection portion 28 of head 21 to a subtank 37 of attachment case 27, which will be described later.

[0011] The drive source 31 includes, for example, a motor and a reduction gear connected to the motor's output shaft, and rotates the feed roller 16, the transport roller 17, the discharge roller 23, etc. The printer 10 drives the drive source 31 to rotate the feed roller 16 and the transport roller 17, thereby transporting the sheet S stored in the paper feed tray 15 to the position of the platen 22. The printer 10 ejects ink 101 supplied from a cartridge 100 attached to an attachment case 27 through a tube 29, through the nozzles 19 of the head 21. For example, the printer 10 includes a carriage that moves back and forth in a main scanning direction that intersects with the direction in which the sheet S is transported by the transport roller 17. The head 21 is mounted on this carriage. The printer 10 ejects ink 101 through the nozzles 19 of the head 21 while moving the carriage from one side to the other in the main scanning direction. As a result, the ink 101 lands on the sheet S supported by the platen 22, printing an image on the sheet S. An image is printed on a partial area (one pass's worth) of the sheet S facing the head 21. Next, the printer 10 causes the transport rollers 17 to transport the sheet S so that the area where the next image is to be printed faces the head 21. The printer 10 alternately repeats these processes to print an image on one sheet S. The printer 10 rotates the discharge rollers 23 to discharge the sheet S on which the image has been printed onto the discharge tray 25. The sheet S discharged onto the discharge tray 25 can be removed from an opening 26 formed in the front surface 13A of the printer 10.

[0012] As shown in FIG. 1(B), an opening 13B is formed on the front surface 13A of the housing 13 at the right end in the left-right direction 2. The housing 13 is provided with a cover 11 that switches between an open state (FIG. 1(B)) in which the opening 13B is open and a closed state (FIG. 1(A)) in which the opening 13B is closed. An attachment case 27 (accommodation section 41) is provided in the space inside the housing 13 that extends beyond the opening 13B. The printer 10 also has a cover sensor 33 (see FIG. 3) for detecting whether the cover 11 is open or closed.

[0013] As shown in FIGS. 2 and 3, the mounting case 27 includes a contact 35, an attachment sensor 36 (see FIG. 3), a subtank 37 (see FIG. 2), an ink amount sensor 38, and a joint 39 (see FIG. 2). The mounting case 27 can accommodate four cartridges 100, one for each of the four colors: black (K), cyan (C), magenta (M), and yellow (Y). The mounting case 27 has slots into which each of the four cartridges 100 can be attached. That is, the mounting case 27 includes four contacts 35, attachment sensors 36, subtanks 37, ink amount sensors 38, and joints 39, one for each of the four cartridges 100. These four sets are provided in the four slots and have the same configuration except that the colors of the ink 101 are different. Therefore, the following description will focus on the configuration of one set. The number of cartridges 100 that can be accommodated in the mounting case 27 is not limited to four, and may be one, five, or more.

[0014] The mounting case 27 is box-shaped and has a storage section 41 that stores the mounted cartridge 100. An opening 41A that communicates with the opening 13B of the housing 13 is formed on the front side of the mounting case 27. The cartridge 100 is attached to and detached from the storage section 41 of the mounting case 27 through the openings 13B and 41A. The cartridge 100 includes a housing 103 and a lid 104. A liquid chamber 103A that stores ink 101 is formed inside the housing 103. The top of the liquid chamber 103A is closed by the lid 104. An IC board 105 on which a memory 110 is mounted is provided on the lid 104. The memory 110 is, for example, a rewritable nonvolatile memory such as an EEPROM. Note that the memory 110 is not limited to an EEPROM, and may be another nonvolatile memory such as a flash memory.

[0015] The contact 35 is attached to, for example, the upper wall 41B of the accommodating section 41. The contact 35 is provided at a position where it comes into contact with an electrode 111 (see FIG. 3) provided on the IC board 105 of the cartridge 100 when the cartridge 100 is attached to the attachment case 27. The contact 35 is electrically connected to the controller 30 (see FIG. 3) of the printer 10. The controller 30 acquires information from the memory 110 of the IC board 105 through the contact 35 and the electrode 111. The controller 30 also writes information to the memory 110 of the IC board 105 through the contact 35 and the electrode 111.

[0016] In this specification, the term "acquire" is used as a concept that does not necessarily require a request. In other words, the concept of "controller 30 acquires information" also includes information being output from memory 110 to controller 30 without a request from controller 30. Therefore, "acquire" is a concept that includes both the case where controller 30 actively reads information from memory 110 and the case where cartridge 100 actively outputs information from memory 110 without a request.

[0017] The mounting case 27 also includes four sub-tanks 37 corresponding to the four cartridges 100, respectively. The sub-tanks 37 are located further rearward than the rear wall of the storage section 41, and are capable of storing ink 101. In the following description, when distinguishing between the ink 101 stored in the liquid chamber 103A of the cartridge 100 and the ink 101 stored in the sub-tank 37, the ink 101 stored in the liquid chamber 103A will be referred to as the first ink 101A, and the ink 101 stored in the sub-tank 37 will be referred to as the second ink 101B. When referring to the ink 101 in the two locations collectively, they will be referred to as ink 101.

[0018] The installation sensor 36 is provided, for example, on the upper wall 41B of the storage section 41 and is a sensor for detecting whether the cartridge 100 is installed in the installation case 27. The ink amount sensor 38 is provided on the bottom wall of the subtank 37 and outputs a different signal to the controller 30 depending on whether the amount of the second ink 101B has decreased below a predetermined amount. This predetermined amount is, for example, an amount that allows printing on several hundred sheets S. When the amount of the second ink 101B falls below the predetermined amount, the cartridge 100 becomes empty. Therefore, in the printer 10, the height of the ink 101 liquid level becomes the height of the detection position of the ink amount sensor 38, and even after the cartridge 100 becomes empty, it is possible to print several hundred sheets.

[0019] An outlet 37A formed in the lower part of the rear wall of the subtank 37 is connected to the connection part 28 of the head 21 via a tube 29. This allows the subtank 37 to supply the second ink 101B from the outlet 37A to the head 21 via the tube 29. The subtank 37 is also connected to the outside of the printer 10 through an air communication passage 37B formed in the upper wall and is open to the atmosphere. The liquid chamber 103A of the cartridge 100 is also connected to the outside of the cartridge 100 through an air communication passage 104A formed in the lid part 104 and is open to the atmosphere. Therefore, the first ink 101A in the liquid chamber 103A and the second ink 101B in the subtank 37 move through the joint 39 due to the difference in head. When the liquid levels of the ink 101 in the liquid chamber 103A and the subtank 37 are the same, an equilibrium state is reached, and in this equilibrium state, the movement of the ink 101 between the liquid chamber 103A and the subtank 37 stops.

[0020] An inlet 37C is formed at the lower end of the front wall of the subtank 37. The inlet 37C is connected to the liquid chamber 103A of the cartridge 100 via a joint 39. The joint 39 has, for example, a mechanism for opening and closing the flow path depending on the installation of the cartridge 100, and closes the flow path when the cartridge 100 is not installed in the installation case 27, and opens the flow path when the cartridge 100 is installed in the installation case 27, thereby connecting the subtank 37 to the liquid chamber 103A.

[0021] (Controller 30) As shown in Figure 3, the controller 30 includes a CPU 43, a ROM 44, a RAM 45, an EEPROM 46, and an ASIC 47. The ROM 44 stores a control program PG that the CPU 43 uses to control the operation of each device. The RAM 45 is used as a storage area for temporarily recording data, signals, and the like used when the CPU 43 executes the control program PG, or as a work area for data processing. The EEPROM 46 stores setting information that should be retained even after the power is turned off. For example, the EEPROM 46 stores the remaining amount Vs, which is the amount of ink in the subtank 37.

[0022] The EEPROM 46 also stores an authentication mandatory flag FG. The authentication mandatory flag FG is information indicating whether or not the authentication process described below needs to be executed. For example, the memory 110 stores four authentication mandatory flags FG corresponding to the four slots of the attachment case 27. The authentication mandatory flag FG is set to a value (e.g., 1) indicating that the authentication process needs to be executed, or a value (e.g., zero) indicating that the authentication process does not need to be executed. The EEPROM 46 is an example of a storage device in this specification. The above-described memory and storage device configurations are also examples. For example, the controller 30 may include a flash memory instead of an EEPROM as a non-volatile memory. The storage device in this specification may be an HDD or SSD, or may be a combination of multiple storage devices. The storage device may also be an external storage device such as an external storage medium such as a USB memory, a network storage, a server, or the memory 110 of the cartridge 100. Therefore, the remaining capacity Vs and the authentication mandatory flag FG may be stored in a device separate from the image forming apparatus.

[0023] In the following description, the controller 30 that executes the control program PG and the like may be referred to simply by its device name. For example, the phrase "the controller 30 drives the motor of the drive source 31 through the ASIC 47" means "the controller 30 executes the control program PG in the CPU 43 and controls the drive source 31 through the ASIC 47, thereby driving the motor." Furthermore, the medium that stores the control program PG and other programs is not limited to the ROM 44 or the like built into the printer 10, but may also be a computer-readable storage medium (such as a USB memory). A computer-readable storage medium is a non-transitory medium. In addition to the above examples, non-transitory media also include storage media such as CD-ROMs and DVD-ROMs. Non-transitory media are also tangible media. On the other hand, an electrical signal carrying a program downloaded from a server on the Internet is a computer-readable signal medium, which is a type of computer-readable medium, but is not included in the category of non-transitory computer-readable storage media.

[0024] The ASIC 47 is an Application Specific Integrated Circuit, and operates the drive source 31, head 21, etc. The controller 30 drives the motor of the drive source 31 via the ASIC 47, thereby rotating the feed roller 16, the transport roller 17, and the discharge roller 23. The controller 30 also outputs a drive signal to the drive element of the head 21 via the ASIC 47, thereby ejecting ink 101 through the nozzles 19 of the head 21. The ASIC 47 can output multiple types of drive signals depending on the amount of ink to be ejected through the nozzles 19.

[0025] 1 and 3, the printer 10 is equipped with, for example, a touch panel 48 and operation buttons 49 as a user interface. Note that the configuration of the user interface equipped in the printer 10 described above is one example. The ASIC 47 is electrically connected to the cover sensor 33, contacts 35, installation sensor 36, and ink amount sensor 38. The controller 30 accesses the memory 110 of the IC board 105 of the cartridge 100 installed in the installation case 27 via the contacts 35.

[0026] The printer 10 also includes a network IF (abbreviation of interface) 51. The network IF 51 is, for example, a LAN interface. The controller 30 can be connected to a PC, the Internet, a server, etc. via the network IF 51. The network IF 51 is not limited to a wired network IF, and may also be a wireless network IF.

[0027] Fig. 4 shows a block diagram of IC substrate 105. As shown in Fig. 4, IC substrate 105 includes, in addition to memory 110, control unit 112 and signal processing circuit 113. Control unit 112 is connected to memory 110 and includes a memory controller that controls writing of information to memory 110 and acquisition of information from memory 110. Signal processing circuit 113 is connected between control unit 112 and electrodes 111 and executes transmission and reception of signals (information) between control unit 112 and electrodes 111.

[0028] The memory 110 of the IC board 105 stores a remaining amount initial value 121, a remaining amount 123, cartridge type information 125, signature information 126, a reset count 127, ID information 128, and equilibrium calculation parameters 129. After being sold by a manufacturer of the cartridge 100 (hereinafter sometimes simply referred to as the manufacturer) and used by a user, the cartridge 100 can be collected, disassembled, cleaned, reassembled, inspected, and the information in the memory 110 can be reset (hereinafter sometimes referred to as the remanufacturer) and sold as a refurbished product. Therefore, in this specification, "refurbishment" refers to the act of returning a used replacement part to its initial state so that it can be reused. In the following description, the cartridge 100 initially sold by the manufacturer will be referred to as a new cartridge 100. Furthermore, the cartridge 100 refurbished by the remanufacturer will be referred to as a refurbished cartridge 100. The manufacturer may also carry out the regeneration.

[0029] The initial remaining amount value 121 is used, for example, as the initial value of the remaining amount of the first ink 101A in a new product or a recycled product. The initial remaining amount values ​​for a new product and a recycled product may be different values. For example, a remanufacturer uses this initial remaining amount value 121 to set the remaining amount 123 at the time of recycling. The remaining amount 123 is a value indicating the remaining amount of the first ink 101A, and is subtracted as the first ink 101A is used.

[0030] The cartridge type information 125 is information indicating the type of cartridge 100. Specifically, the cartridge type information 125 is information indicating whether the cartridge 100 is a commercially available cartridge 100 or a cartridge 100 packaged with the printer 10. The cartridge type information 125 is also information indicating the color of the ink 101 in the cartridge 100. Specifically, the information indicating the color of the ink 101 is information (such as a bit value) indicating one of black (K), cyan (C), magenta (M), and yellow (Y), for example. The cartridge type information 125 also includes information on the destination of the cartridge 100. Specifically, the destination information is information that can identify the country, region, state, etc. where the cartridge 100 is to be sold or used. The destination information may be information on a country-by-country basis, or may be information indicating a country, region, etc.

[0031] The signature information 126 is information used to authenticate the cartridge 100, and is a hash value used in the authentication process described below. The signature information 126 is encrypted, for example, by a predetermined encryption program. The signature information 126 may also be unencrypted information. The reset count 127 indicates the number of times the cartridge 100 has been played, and is, for example, set to zero as an initial value and incremented by +1 each time the cartridge 100 is played. The ID information 128 is information for individually identifying the cartridge 100 (IC substrate 105), and is, for example, set to a unique value (such as a number or letter) for each cartridge 100.

[0032] The equilibrium calculation parameter 129 is a parameter of an equilibrium calculation formula for calculating the ink amount of the first ink 101A from the total amount of ink 101, which is the sum of the amount of the first ink 101A in the cartridge 100 (liquid chamber 103A) and the amount of the second ink 101B in the subtank 37. A method for calculating the ink amounts of the first ink 101A and the second ink 101B from the total amount of ink 101 using the equilibrium calculation formula can be performed using a known technique, for example, as described in Japanese Patent Application Laid-Open No. 2019-69568. Therefore, a detailed description of the equilibrium calculation will be omitted. However, as described above, the ink 101 moves between the liquid chamber 103A and the subtank 37 until an equilibrium state is reached due to the head difference. Therefore, the relationship between the total amount of ink 101 (first and second inks 101A and 101B) in the equilibrium state and the ink amounts in the subtank 37 and the liquid chamber 103A can be approximated using a function based on actual measurement values. Parameters related to this function (such as the slope and intercept) are set in the equilibrium calculation parameters 129. The controller 30 can calculate the remaining amount Vs of the subtank 37 and the remaining amount Vc of the cartridge 100 by using the equilibrium calculation parameters 129.

[0033] Furthermore, the remaining amount initial value 121, cartridge type information 125, signature information 126, ID information 128, and balance calculation parameters 129 are fixed values ​​set by the manufacturer at the time of manufacture, and are values ​​that are not changed before and after access by the controller 30 or regeneration of the cartridge 100. This information is stored, for example, in a storage area where information is not overwritten (modified) by the controller 30.

[0034] The memory 110 is also capable of storing identification information 131. This identification information 131 is information used for simplified authentication, which will be described later. For example, when a new product or a recycled product is sold, the identification information 131 is not stored in the memory 110. If the identification information 131 is stored in the cartridge 100 before recycling, it is deleted in the recycling process. The identification information 131 is information that is written to the memory 110 when authentication in the main authentication process, which will be described later, is successful. For this reason, the identification information 131 is shown by a dashed line in FIG. 4.

[0035] The information stored in the memory 110 and the storage destination configuration described above are merely examples. For example, the initial remaining amount value 121 and the balance calculation parameter 129 for a recycled product may be stored in the memory 110 separately from the initial remaining amount value 121 and the balance calculation parameter 129 for a new product. Fixed values ​​such as the initial remaining amount value 121 may also be stored in a ROM separate from the memory 110. When an encryption key (such as a private key) is used for authentication instead of a hash value, the encryption key may be stored in the memory 110 or the ROM. When the cartridge 100 is a non-recycled cartridge, information related to the recycled product, such as the reset count 127, may not be stored in the memory 110. The identification information 131 may also be stored in a storage device other than the memory 110.

[0036] The control unit 112 also includes a first logic circuit 132 and a second logic circuit 133. The first logic circuit 132 is a processing circuit that executes calculations related to authentication in the authentication process. The second logic circuit 133 is a processing circuit used for processing (such as calculations) other than the authentication process. Examples of processing other than the authentication process include calculating a checksum of predetermined data and verifying whether the calculation results match. Alternatively, examples of processing other than the authentication process include generating random numbers. Therefore, examples of processing other than the authentication process may include various processes that must be executed by the cartridge 100 or the printer 10, or processes for implementing functions provided by the IC board 105. The first and second logic circuits 132 and 133 may be implemented by hardware processing, such as logic circuits in an ASIC or FPGA (Field Programmable Gate Array). Alternatively, the first and second logic circuits 132 and 133 may be implemented by software processing, such as by executing a program on a CPU.

[0037] (Cartridge authentication process) Next, the cartridge authentication process executed by the controller 30 will be described with reference to Fig. 5. The controller 30 executes this cartridge authentication process to authenticate the cartridge 100. For example, when the cartridge 100 is attached to the attachment case 27 (accommodating section 41), the controller 30 executes the control program PG stored in the ROM 44 and executes the process of Fig. 5. Therefore, the controller 30 executes the process of Fig. 5 when the cartridge 100 is attached to the attachment case 27 for the first time or when the attached cartridge 100 is replaced.

[0038] The condition for starting the process shown in Fig. 5 is not limited to the condition that the cartridge 100 is installed or replaced. For example, the controller 30 may execute the process of Fig. 5 each time the cover sensor 33 detects the opening or closing of the cover 11. Furthermore, even if the cartridge 100 is replaced, the controller 30 may not execute the process of Fig. 5 if the ID information 128 of the cartridge 100 before and after replacement matches. Furthermore, the controller 30 may execute the process of Fig. 5 each time a predetermined number of sheets (for example, one sheet) are printed. Furthermore, the controller 30 may execute the process of Fig. 5 for the installed cartridge 100 each time the printer 10 is powered on.

[0039] To avoid complicating the explanation, the following description will be directed to a case where one of the four cartridges 100 that can be attached to the attachment case 27 is processed. For example, the case where one cartridge 100 is replaced will be described. However, when processing multiple cartridges 100, the processing can be performed by executing the processing described below for each cartridge 100, just as in the case of one cartridge. Therefore, the controller 30 may start the processing of FIG. 5 when at least one of the four cartridges 100 is replaced, etc.

[0040] When the controller 30 starts the process of FIG. 5, first, in step (hereinafter simply referred to as S) 1, it determines whether the color, destination, and remaining amount of the replaced cartridge 100 are appropriate. If all three conditions, color, destination, and remaining amount, are appropriate (S1: YES), the controller 30 executes S2. If at least one of the three conditions is not appropriate (S1: NO), the controller 30 displays an error screen on the touch panel 48 (S3). After displaying the error screen, the controller 30 ends the process shown in FIG. 5. If the controller 30 executes S3, it prohibits the use of the replaced cartridge 100. Specifically, for example, the controller 30 does not accept printing using the replaced cartridge 100 and maintains the error screen displayed until another cartridge 100 is installed.

[0041] The controller 30 determines whether the color is appropriate based on the cartridge type information 125 stored in the memory 110 of the replaced cartridge 100. As described above, the mounting case 27 has four slots each equipped with a contact 35, a mounting sensor 36, etc., corresponding to each of the colors black, cyan, magenta, and yellow. The controller 30 determines whether the color of the slot into which the replaced cartridge 100 is mounted matches the color of the mounted cartridge 100. The color of the cartridge 100 here refers to the color indicated by the cartridge type information 125 stored in the memory 110 of the cartridge 100. In other words, the controller 30 determines whether a cartridge 100 containing ink 101 of the same color as the ink 101 of the removed cartridge 100 has been mounted. The controller 30 determines that the color is appropriate when the color of the slot into which the cartridge 100 is mounted matches the color of the mounted cartridge 100. Furthermore, if the colors do not match (S1: NO), the controller 30 displays, for example, a message indicating that the colors of the replaced cartridge 100 do not match on the error screen of the touch panel 48 (S3).

[0042] In addition, in S1, the controller 30 determines the destination based on the cartridge type information 125 stored in the memory 110 of the replaced cartridge 100. For example, information on the destination of the printer 10 (Japan, America, etc.) is stored in the ROM 44 of the controller 30. If the destination information in the ROM 44 matches the destination information in the cartridge type information 125, the controller 30 determines that the destination is appropriate. If the two destinations do not match (S1: NO), the controller 30 displays, for example, a message indicating that the destination of the replaced cartridge 100 does not match on an error screen of the touch panel 48 (S3).

[0043] The controller 30 also determines whether the remaining amount is appropriate by determining whether the remaining amount 123 stored in the memory 110 of the replaced cartridge 100 is equal to or less than a predetermined threshold. For example, if the remaining amount 123 is greater than zero (threshold), that is, if even a small amount of ink 101 remains, the controller 30 determines that the remaining amount is appropriate. If the remaining amount 123 is zero, the controller 30 determines that the remaining amount is inappropriate (S1: NO), and displays, for example, a message indicating that the remaining amount of the replaced cartridge 100 is zero on an error screen of the touch panel 48 (S3). Note that the controller 30 can calculate the total amount of ink 101 by adding the remaining amount 123 (remaining amount Vc) in the memory 110 and the remaining amount Vs in the EEPROM 46 at the time the cartridge 100 is installed. The controller 30 executes the balance calculation described above in response to the use of the ink 101, such as printing or nozzle check, calculates the remaining amount Vc of the first ink 101A, and stores the calculated remaining amount Vc in the memory 110 as the remaining amount 123. Therefore, the latest remaining amount 123 is stored in the memory 110. The controller 30 also calculates the remaining amount of the second ink 101B by subtracting the remaining amount Vc from the total amount, and updates the remaining amount Vs in the EEPROM 46.

[0044] Next, in S2, the controller 30 executes acquisition of the identification information 131. As described above, the identification information 131 is not stored in the memory 110 of a cartridge 100 that has been sold as a new product or a refurbished product, i.e., a brand new cartridge 100. In the next S5, the controller 30 determines whether or not the identification information 131 was acquired in S2. If the identification information 131 was acquired in S2 (S5: YES), the controller 30 executes S6, and if the identification information 131 was not acquired (S5: NO), the controller 30 executes the main authentication process of S11. Therefore, when a brand new cartridge 100 that has never been installed in the installation case 27 is installed, the controller 30 executes the main authentication process for the cartridge 100.

[0045] In S6, the controller 30 determines whether the authentication mandatory flag FG is set to a value indicating that it is not necessary to execute this authentication process (hereinafter referred to as the authentication mandatory flag FG being off). The controller 30 determines whether the authentication mandatory flag FG corresponding to the slot into which the replaced cartridge 100 is attached is set to off. If the authentication mandatory flag FG is off (S6: YES), the controller 30 executes S7. Furthermore, if the authentication mandatory flag FG is set to a value indicating that it is necessary to execute this authentication process (hereinafter referred to as the authentication mandatory flag FG being on) (S6: NO), the controller 30 executes the authentication process of S11.

[0046] In S7, the controller 30 determines whether or not it is necessary to execute the main authentication process. If the controller 30 determines that it is necessary to execute the main authentication process (S7: YES), it executes S8 and then executes the main authentication process (S11). If the controller 30 determines that it is not necessary to execute the main authentication process in S7 (S7: NO), it executes simplified authentication process (S9). The simplified authentication process of S9 is a process for authenticating the cartridge 100, and is a process for executing authentication that requires a shorter processing time than the main authentication process. Therefore, in S7, the controller 30 determines whether to execute the main authentication process or the simplified authentication process that requires a shorter processing time.

[0047] When the controller 30 performs subsequent authentication for a cartridge 100 that has successfully passed authentication through the main authentication process of S11 (hereinafter sometimes simply referred to as main authentication), it switches between the main authentication process of S11 and the simplified authentication process of S9 with a preset probability. For example, the controller 30 performs the simplified authentication process with a probability of 1 / 10. For example, after the cartridge 100 is replaced, the controller 30 performs the process of FIG. 5 on the installed cartridge 100 every time a predetermined number of pages are printed. In other words, while the cartridge 100 is installed in the printer 10, the authentication process of FIG. 5 is repeatedly performed every time a predetermined number of pages are printed. For example, the controller 30 performs a calculation to randomly generate an integer from among integers 1 to 10, and if the calculation result is not a specific integer (e.g., 1), it makes a positive determination in S7 (S7: YES) and performs the main authentication process of S11. If the calculation result is a specific integer, the controller 30 makes a negative determination (S7: NO) and performs the simplified authentication process of S9. This allows simple authentication processing to be performed with a fixed probability of 1 / 10.

[0048] In S8, the controller 30 turns on the authentication mandatory flag FG. Because the authentication mandatory flag FG is stored in the EEPROM 46, the stored state and the set value (on or off) are maintained even when the printer 10 is powered on or off. The authentication mandatory flag FG also maintains its set value even when the printer 10 settings are initialized. As a result, for a slot for which it has been determined that the authentication process is to be executed, the authentication process is executed, as described below, and until the authentication is successful and the authentication mandatory flag FG is turned off (S12: YES, S13), a negative determination is made in S6 (S6: NO), and the authentication process of S11 is always executed. Even when the printer 10 is powered on or off or the printer 10 settings are initialized, a negative determination is made in S6 (S6: NO), and the authentication process of S11 is executed.

[0049] After executing S8, the controller 30 executes a main authentication process (S11) and determines whether the main authentication is successful (S12). The controller 30 executes authentication using, for example, a hash value of the signature information 126. In S11, the controller 30 instructs the replaced cartridge 100 to calculate a hash value. The control unit 112 of the IC board 105 calculates the hash value using the first logic circuit 132 and transmits the calculated hash value to the controller 30. The first logic circuit 132 calculates the hash value using the remaining amount initial value 121, cartridge type information 125, and ID information 128 stored in the memory 110 and a predetermined calculation formula. The calculation of the hash value may be executed by the controller 30.

[0050] When the controller 30 acquires the hash value from the first logic circuit 132, it determines whether the acquired hash value matches the hash value indicated by the signature information 126 stored in the memory 110 (S12). For example, an authentication program capable of decrypting the encrypted signature information 126 is stored in the ROM 44 of the printer 10. This authentication program corresponds to the encryption of the signature information 126 and is created by the manufacturer of the printer 10 or the manufacturer of the cartridge 100. In other words, the signature information 126 is encrypted by an encryption program corresponding to this authentication program when the cartridge 100 is manufactured. The controller 30 executes this authentication program and decrypts the encrypted signature information 126. The controller 30 determines whether the authentication is successful or not based on whether the hash value calculated by the first logic circuit 132 matches the hash value obtained by decrypting the signature information 126 (S12). For example, when the cartridge 100 is manufactured, values ​​such as the initial remaining amount value 121 and a hash value calculated using a predetermined calculation formula are encrypted and stored in the memory 110 as the signature information 126. As a result, if information such as the initial remaining amount value 121 is tampered with in a manner not permitted by the manufacturer, the unauthorized tampering can be detected by comparing the hash values.

[0051] If the two hash values ​​match, the controller 30 determines that the authentication has been successful (S12: YES) and executes S13. If the two hash values ​​do not match, the controller 30 determines that the authentication has failed (S12: NO) and displays a message indicating that the authentication has failed on an error screen (S3). The controller 30 does not permit use of a cartridge 100 that has failed the authentication, just as it would if the determination in S1 was negative. The controller 30 also determines that the authentication has failed (S12: NO) and executes S3 if the decryption of the signature information 126 fails. This makes it possible to prevent the use of a cartridge 100 with forged signature information 126.

[0052] In S13, the controller 30 sets the authentication required flag FG to OFF. That is, if the authentication is successful (S12: YES), the controller 30 sets the authentication required flag FG to OFF. After executing S13, the controller 30 sets the identification information 131 (S15). The controller 30 sets, as the identification information 131, information indicating a unique value associated with the printer 10, a value different from the identification information 131 used by other printers 10 (S15). Specifically, the identification information 131 is, for example, the serial number of the printer 10. Alternatively, the identification information 131 may be a value calculated using the serial number and a predetermined calculation formula. In this way, device-specific information of the printer 10 can be set as the identification information 131.

[0053] After executing S15, the controller 30 writes the identification information 131 set in S15 to the memory 110 of the replaced cartridge 100, i.e., the cartridge 100 that has been successfully authenticated (S16). After executing S16, the controller 30 ends the processing shown in FIG. 5. The controller 30 permits the use of the cartridge 100 that has been successfully authenticated. For example, the controller 30 permits printing using the ink 101 in the replaced cartridge 100.

[0054] Furthermore, when writing the identification information 131 to the memory 110 in S16, if another piece of identification information 131 is already stored in the memory 110, the controller 30 overwrites the other stored identification information 131 with the new identification information 131. Suppose that a cartridge 100 in which identification information 131 has been written in an arbitrary printer 10 (for example, printer A) is installed in another printer 10 (for example, printer B). In this case, the controller 30 of printer B overwrites the identification information 131 written by printer A with the serial number (identification information 131) of printer B in S16. This makes it possible to store only one piece of identification information 131 in the memory 110.

[0055] The controller 30 does not have to overwrite the identification information 131. For example, when writing the identification information 131 to the memory 110 in S16, if another identification information 131 is already stored in the memory 110, the controller 30 may store the new identification information 131 in the memory 110 while leaving the other stored identification information 131. This allows the identification information 131 of each printer 10 that has previously successfully passed full authentication to be accumulated in the memory 110. In this case, the controller 30 may make a positive determination (S5: YES) in S5, for example, if the identification information 131 (serial number) of the printer itself is included among the multiple pieces of identification information 131 stored in the memory 110. Furthermore, in S9 and S17, described below, the controller 30 may determine that simplified authentication has been successful if the identification information 131 (serial number) of the printer itself is included among the multiple pieces of identification information 131 stored in the memory 110 (S17: YES). Furthermore, in S15 and S16, if the identification information 131 (serial number) of the controller 30 itself has already been stored in the memory 110, the controller 30 does not need to add the identification information 131 to the memory 110.

[0056] Furthermore, after completing the process of FIG. 5, the controller 30 restarts the process of FIG. 5 after printing a predetermined number of sheets, etc. As a result of the previous process of S16 of FIG. 5, the identification information 131 is stored in the memory 110. Therefore, the controller 30 makes a positive determination in S5 (S5: YES). Furthermore, because the authentication required flag FG was turned off in the previous S13 of FIG. 5, the controller 30 makes a positive determination in S6 (S6: YES). The controller 30 makes a positive determination in S7 with a probability of 9 / 10 (S7: YES) and executes the same processes as described above (S8 to S16). Then, the controller 30 makes a negative determination in S7 with a probability of 1 / 10 (S7: NO) and executes the simplified authentication process of S9. The controller 30 executes the simplified authentication process in S9, and determines whether the authentication in the simplified authentication process (hereinafter, sometimes simply referred to as simplified authentication) was successful in S17 (S17). In S9, the controller 30 checks whether the identification information 131 is stored in the memory 110 of the cartridge 100, and if the appropriate identification information 131 is stored, the controller 30 determines that the simplified authentication was successful (S17: YES). The appropriate identification information 131 here refers to the serial number of the printer 10. For example, in S9, the controller 30 executes a process in the second logic circuit 133 of the control unit 112 to determine whether the serial number stored in the ROM 44 of the printer 10 matches the number indicated by the identification information 131 obtained from the memory 110. For example, the controller 30 may input the bit values ​​of the serial number and the number of the identification information 131 into an exclusive OR (XOR) circuit of the second logic circuit 133, and determine that the simplified authentication was successful if the output bit values ​​are all zero. If the simplified authentication was successful (S17: YES), the controller 30 ends the process shown in FIG. 5. The controller 30 permits use of the cartridge 100 for which the simplified authentication was successful. As a result, unless the cartridge 100 is replaced, the controller 30 executes simplified authentication for the same cartridge 100 with a probability of 1 / 10, thereby reducing the processing time for authentication processing.

[0057] Furthermore, if the controller 30 is unable to acquire the identification information 131 in S9 due to a failure in reading from the memory 110, or if the acquired identification information 131 does not match the serial number of the controller 30's own device, the controller 30 determines that the simplified authentication has failed (S17: NO) and executes S3. The controller 30 displays a message indicating that the authentication has failed on an error screen (S3). The controller 30 prohibits the use of a cartridge 100 for which simplified authentication has failed. The controller 30 may also delete the identification information 131 from the memory 110 based on certain conditions. For example, if simplified authentication has failed (S17: NO), the controller 30 may delete all of the identification information 131 stored in the memory 110. The controller 30 may also delete the identification information 131 used in simplified authentication, for example, every time simplified authentication has been successfully performed a predetermined number of times. As a result, in the next processing of FIG. 5, a negative determination is made in S5 (S5: NO), and full authentication is forcibly performed.

[0058] Note that the processing content and processing order of each step in the flowchart shown in FIG. 5 are merely examples. For example, in S1, the controller 30 determines the color, destination, and remaining amount 123 of the ink 101. However, the controller 30 may determine only one of the three conditions. The color of the ink 101 in S1 is an example of the type of consumable material in this specification. The type of consumable material in this specification is not limited to color, and may also be, for example, the type of ink 101 (pigment ink, dye ink, etc.). Therefore, in S1, the controller 30 may make a negative determination (S1: NO) if the type of ink 101 in the replaced cartridge 100 does not match the appropriate type for use in the printer 10. In addition, if toner is used as a consumable material, i.e., if the printer 10 is an electrophotographic image forming apparatus, the controller 30 may determine the color of the toner in S1.

[0059] Furthermore, the method of determining the destination information in S1 is one example. For example, the controller 30 may determine the destination based on the ID information 128 acquired from the cartridge 100, or may send the ID information 128 to the manufacturer's server and inquire whether the destination is correct. Furthermore, although the controller 30 determined in S1 whether the remaining amount 123 is zero, it may instead set a predetermined amount greater than zero as a threshold and determine whether the remaining amount 123 is equal to or less than that threshold. This threshold may be, for example, the minimum amount at which the first ink 101A stored in the cartridge 100 can be used.

[0060] Furthermore, in S2 and S5, the controller 30 determines whether or not the identification information 131 is stored in the memory 110, but this is not limiting. For example, the controller 30 may determine whether or not a valid value is stored as the identification information 131. An invalid value (for example, zero) may be stored in the memory 110 as the identification information 131 until the main authentication is successful, and if the main authentication is successful, the controller 30 may store a valid value (for example, 1) as the identification information 131 in the memory 110. In this case, an invalid value of the identification information 131 may be stored in the memory 110 of a new cartridge 100.

[0061] (Regarding S7's decision) Furthermore, the controller 30 executes the simplified authentication process at a certain probability (for example, a probability of 1 / 10) in S7, but the present invention is not limited to this. (Determination method based on a predetermined timing) For example, the controller 30 may switch between the main authentication process and the simplified authentication process at a preset timing when performing subsequent authentication on a cartridge 100 that has successfully passed main authentication. The controller 30 may, for example, count the number of consecutive successful main authentication processes, and if main authentication has been successful a preset X number of times, make a negative determination in S7 in the next processing shown in Fig. 5 (S7: NO) and perform the simplified authentication process of S9. This allows the process of performing the simplified authentication process only once after main authentication has been successful X number of times in a row to be repeatedly performed.

[0062] Alternatively, the controller 30 may execute the simplified authentication process consecutively a preset number of Y times. In this case, the main authentication process is executed consecutively X times, and then the simplified authentication process is executed consecutively Y times. The controller 30 may also switch the values ​​of X and Y as appropriate.

[0063] (Random number determination method) Furthermore, for example, when performing subsequent authentication of a cartridge 100 that has successfully passed full authentication, the controller 30 may use a random number to randomly switch between full authentication processing and simplified authentication processing. The controller 30 may obtain a random number from the random number generation circuit in S7, and if the obtained random number is divided by a predetermined integer and the remainder is zero, i.e., the random number is divisible, a negative determination is made (S7: NO), and the simplified authentication processing of S9 is performed. Alternatively, the controller 30 may calculate a random number using the results of a calculation that uses the execution time of S7, the cumulative number of printed sheets when S7 was executed, and the like. The controller 30 may also determine the number of consecutive executions of full authentication processing before the next execution of simplified authentication processing, based on the value of the calculated random number.

[0064] Furthermore, the controller 30 may change the probability of S7 in accordance with changes in the usage state of the printer 10 or the cartridge 100. Therefore, the controller 30 may change the probability used in the determination of S7 (the probability of executing this authentication process) under certain conditions. (Method 1 for determining variable probability) For example, the controller 30 may gradually decrease the probability of executing the main authentication process as the number of consecutive successful authentication attempts increases. The controller 30 stores the number of consecutive successful main authentication attempts and simplified authentication attempts, i.e., the number of consecutive positive determinations in S12 and S17, in the EEPROM 46. When the controller 30 performs authentication on a cartridge 100 that has successfully passed main authentication (S12: YES) from the next time onward, the controller 30 checks the number of successes stored in the EEPROM 46 in S7. As the number of successes stored increases, the controller 30 decreases the probability of making a positive determination in S7, i.e., the probability of executing the main authentication process. This allows the probability to be changed depending on the success of the authentication.

[0065] Specifically, for example, when executing S7 for the first time, the controller 30 executes the determination in S7 so that the simplified authentication process will be executed with a probability of 1 / 10. When the main authentication is successful in S12 (S12: YES) or the simplified authentication is successful in S17 (S17: YES), the controller 30 increments the number of successes in the EEPROM 46 by 1 each time the authentication is successful. For example, when the controller 30 repeatedly executes the process of FIG. 5 and the number of successes reaches 10, and then executes S7 in the next process of FIG. 5, the number of successes in the EEPROM 46 is 10, so the probability of executing the simplified authentication process is set to 1 / 9. As a result, the controller 30 makes a negative determination in S7 with a probability of 1 / 9 (S7: NO) and executes the simplified authentication process (S9).

[0066] As in the above process, the controller 30 increments the number of successes in the EEPROM 46 by +1 each time authentication is successful. Then, when the controller 30 executes S7 and the number of successes reaches 20, the controller 30 reduces the probability to 1 / 8. Similarly, the controller 30 reduces the probability to 1 / 9, 1 / 8, 1 / 7, 1 / 6, 1 / 5, 1 / 4, 1 / 3, and 1 / 2 as the number of successes increases to 10, 20, 30, 40, 50, 60, 70, and 80. This reduces the probability of executing the full authentication process as the number of consecutive successful attempts at full authentication and simplified authentication increases. Users who use cartridges 100 that are consistently successful in authentication are likely to be using genuine cartridges and unlikely to be using counterfeit cartridges. Therefore, by reducing the probability of executing the full authentication process when authentication is consistently successful, the time required for authentication is shortened for high-quality users, improving usability.

[0067] In the above description, the number of successes of both the main authentication process and the simplified authentication process is counted, but this is not limiting. The controller 30 may decrease the probability of executing the main authentication process depending on the number of consecutive successes in either the main authentication process or the simplified authentication process. The controller 30 may count only the number of successes of the main authentication or only the number of successes of the simplified authentication. The controller 30 may then decrease the probability of executing the main authentication process depending on the increase in the number of successes.

[0068] (Method 2 for determining variable probability) Furthermore, the controller 30 may lower the probability of executing the main authentication process as the number of cartridges 100 that have been successfully authenticated in the past increases as multiple cartridges 100 are replaced. For example, the controller 30 stores in the EEPROM 46 the number of times the main authentication process executed for the first time after the cartridge 100 is replaced, i.e., the number of times the main authentication executed for the first time on a brand new cartridge 100 is successful. Then, the probability of S7 may be lowered as the number of times the first main authentication is successful increases.

[0069] Specifically, FIG. 6 is a diagram illustrating variable probability determination method 2. As shown in FIG. 6, when cartridge A is installed and the first actual authentication is successful, the controller 30 stores 1 as the number of successes. The controller 30 executes the simplified authentication process for cartridge A with a probability of 1 / 10. Next, when cartridge A is replaced with cartridge B and the first actual authentication is successful, the controller 30 sets the number of successes to 2. The controller 30 executes the simplified authentication process for cartridge B with a probability of 1 / 9. In this way, as the printer 10 is used for a longer period of time, and the cartridges 100 are replaced with A, B, C, D, E, F, G, and H, and the first actual authentication is successful, the controller 30 decreases the probability to 1 / 9, 1 / 8, 1 / 7, 1 / 6, 1 / 5, 1 / 4, 1 / 3, and 1 / 2. This reduces the probability that the main authentication process will be executed for a user who continues to use a cartridge 100 that has passed main authentication, i.e., a user who continues to use a genuine product. Note that if main authentication or simplified authentication fails, the controller 30 may reset the number of successes to zero.

[0070] (Method 3 for determining variable probability) Furthermore, the controller 30 may lower the probability of executing the authentication process as the reset count 127 increases, i.e., as the number of times the cartridge has been recycled increases. FIG. 7 is a diagram for explaining variable probability determination method 3. As described above, the memory 110 stores the reset count 127, which is the number of times the cartridge 100 containing the memory 110 has been recycled. When a remanufacturer performs a recycling operation on a cartridge 100, the remanufacturer increments the reset count 127 of the cartridge 100 by 1. In the determination of S7, the controller 30 may lower the probability of executing the authentication process as the reset count 127 increases. For example, the controller 30 decreases the probability by 1 / 9, 1 / 8, 1 / 7, 1 / 6, 1 / 5, 1 / 4, 1 / 3, and 1 / 2 as the reset count 127 increases (10, 20, 30, 40, 50, 60, 70, and 80). 7, even when a recycled cartridge 100 is used in a different printer 10 (printer A, B, C, etc.), the probability can be reduced with each increase in the reset count 127. The probability of executing this authentication process can be reduced with each increase in the number of times the cartridge 100 has been recycled, i.e., for a cartridge 100 that has been reused more times.

[0071] If a genuine cartridge 100 is not properly remanufactured by a remanufacturer, the reset count 127 will not increase. In other words, a cartridge 100 with a higher reset count 127 is more likely to have been properly remanufactured repeatedly. In an environment where cartridges 100 that have been repeatedly remanufactured are used, there is a high possibility that the cartridges 100 are being properly managed. That is, there is a high possibility that the user is a good user who reuses cartridges 100 in an authorized manner. Therefore, the probability of executing this authentication process can be reduced for users who use cartridges 100 with a higher reset count 127, i.e., users who use cartridges in an authorized manner. The above-described method of determining the variable probability is merely an example. For example, the controller 30 may reduce the probability of executing this authentication process depending on the length of use of the printer 10 or cartridge 100, the cumulative number of printed pages, or the number of cartridges 100 used. Furthermore, the probability of executing this authentication process may also be reduced for cartridges 100 remanufactured by the manufacturer, as in the case of the remanufacturer described above.

[0072] (Regarding the authentication process in S11 and S12) Furthermore, the details of the main authentication process in S11 and S12 described above are merely examples, and the details of the main authentication process may be changed as appropriate. For example, the controller 30 may perform main authentication using multiple hash values. The controller 30 may calculate a hash value for each of the remaining amount initial value 121, cartridge type information 125, signature information 126, etc., and determine whether each hash value matches the hash value (signature information 126) stored in the memory 110.

[0073] Alternatively, electronic signature information (such as an encrypted electronic document) may be used as the signature information 126. For example, the signature information 126 of an electronic document encrypted using a private key known only to the manufacturer is stored in the memory 110. A public key is also stored in the ROM 44 of each printer 10. The controller 30 may then determine that the main authentication has been successful (S12: YES) if the signature information 126 can be decrypted using the public key in S11 and S12, or if the content of the decrypted electronic document is appropriate. In S12, the controller 30 may also transmit the signature information 126 and ID information 128 acquired from the memory 110 in S11 to an authentication server to authenticate the cartridge 100. Therefore, the main authentication in S11 and S12 may employ a known authentication method used for electronic signatures, etc.

[0074] (Regarding specific information 131 of S15) Furthermore, in S15, the controller 30 uses the serial number of the printer 10, that is, information unique to the printer 10, as the identification information 131, but this is not limiting. (Another pattern 1 of specific information 131) For example, information shared among a plurality of different printers 10 may be used as the identification information 131. Specifically, for example, a value determined by the manufacturer of the printer 10 and information that can be used as the identification information 131 in different printers 10 manufactured by the same manufacturer may be set as the identification information 131. In this case, a first printer 10 (e.g., printer A) can successfully perform simplified authentication of the cartridge 100 installed in the first printer 10 using the identification information 131 stored in the memory 110. Furthermore, a second printer 10 (e.g., printer B) different from printer A can also successfully perform simplified authentication of the cartridge 100 installed in printer B using the identification information 131 stored in the memory 110 by printer A.

[0075] In this case, before executing S15, the controller 30 may determine whether or not the identification information 131 is stored in the memory 110. If the identification information 131 is already stored in the memory 110, the controller 30 may not execute S15 and S16 and may not write the identification information 131 to the memory 110. As a result, for cartridges 100 for which printer A has successfully completed main authentication (S12: YES) and written the identification information 131, printer B will not need to write the identification information 131 if printer A also successfully completes main authentication. Printer B can then perform simplified authentication using the identification information 131 written by printer A.

[0076] A common value determined by the manufacturer can be used as the identification information 131. Alternatively, a common value may be set depending on the model number of the printer 10 and the type of cartridge 100 or IC board 105. In this case, the controller 30 of each printer 10 may determine whether the identification information 131 stored in the memory 110 is a common value that can be used by the printer 10 before executing S15. In other words, the controller 30 may determine whether the identification information 131 set by another printer 10 is information that can be used for simplified authentication of the printer 10, and if it cannot be used, the controller 30 may overwrite the identification information 131.

[0077] Alternatively, encrypted information may be used as the identification information 131. For example, the manufacturer of the printers 10 stores a common key of a common key encryption system in the ROM 44 of each printer 10. If the main authentication is successful, the controller 30 of printer A encrypts the ID information 128 using the common key in S15, for example, and writes the encrypted information to the memory 110 as the identification information 131 (S16). Then, the controller 30 of the other printer B can decrypt the identification information 131 using the common key in S9, and if the decrypted information matches the ID information 128 of the replaced cartridge 100, it may determine that the simplified authentication is successful (S17: YES).

[0078] (Another pattern 2 of specific information 131) The identification information 131 may also be managed by a device separate from the printer 10, for example, a server on a network. The server has a database that associates the identification information 131 with the identification information (such as the ID information 128) of the cartridge 100. If the main authentication is successful in S12 (S12: YES), the controller 30 transmits the ID information 128 of the replaced cartridge 100 to the server via the network IF 51 and inquires about the identification information 131. The server searches the database for the identification information 131 associated with the acquired ID information 128 and transmits the detected identification information 131 to the printer 10 that issued the inquiry. The controller 30 writes the identification information 131 acquired from the server to the memory 110. This allows the identification information 131 to be collectively managed by the server. Furthermore, the server can determine and set which cartridge 100 should have which identification information 131 written to it. For example, different specific information 131 can be set and managed depending on the color, type, model number, version, etc. of the cartridge 100.

[0079] Furthermore, if some kind of problem occurs, such as if the identification information 131 is leaked, the identification information 131 can be changed all at once by the server. In this case, for example, if the simplified authentication in S17 fails, the controller 30 may transmit the ID information 128 to the server to inquire about the identification information 131. Then, if the identification information 131 acquired from the server matches the identification information 131 stored in the memory 110, the controller 30 may determine that the simplified authentication has been successful (S17: YES).

[0080] (Regarding the simple authentication process for S9 and S17) Furthermore, in the simplified authentication process of S9 and S17, the controller 30 determines whether specific information 131 that matches the serial number of the printer 10 is stored in the memory 110, but the method of simplified authentication is not limited to this. For example, the controller 30 may determine that the simplified authentication was successful when the specific information 131 shared by multiple different printers 10 is stored in the memory 110, as described above (different pattern 1 of the specific information 131) (S17: YES). Alternatively, the controller 30 may determine that the simplified authentication has been successful if the specific information 131 obtained from the server is stored in the memory 110, as described above (another pattern 2 of the specific information 131) (S17: YES).

[0081] (Another simple authentication process 1) Furthermore, in the simplified authentication process, the controller 30 may perform a calculation based on the identification information 131 and perform authentication based on the calculation result, rather than simply determining whether the identification information 131 is stored. For example, the controller 30 may store, as authentication information, the value of a calculation result obtained by using the serial number of the printer 10 and a predetermined calculation formula in the EEPROM 46 of the printer 10. If the authentication is successful, the controller 30 writes the serial number of the printer 10 to the memory 110 as the identification information 131 in S16. In the simplified authentication process in S17, the controller 30 may determine whether the identification information 131 stored in the memory 110 is correct based on the authentication information held by the printer 10. If the result of the calculation using the identification information 131 stored in the memory 110 and the predetermined calculation formula matches the authentication information in the EEPROM 46, the controller 30 may determine that correct information has been stored as the identification information 131, i.e., that the simplified authentication was successful (S17: YES). Furthermore, if the calculation result does not match the authentication information, the controller 30 may determine that incorrect identification information 131 has been stored, that is, that the simplified authentication has failed (S17: NO).

[0082] This (another simplified authentication process 1) can also be applied to the above-mentioned (another pattern 1 of the specific information 131) and (another pattern 2 of the specific information 131). Specifically, the controller 30 may store, as authentication information, in the EEPROM 46, for example, a calculation result obtained by using the specific information 131 shared by a plurality of different printers 10 and a predetermined calculation formula. The controller 30 may also store, as authentication information, a calculation result obtained by using the specific information 131 acquired from the server and a predetermined calculation formula.

[0083] (Another simple authentication process 2) Furthermore, in S15, the controller 30 may perform a calculation based on the authentication information held by the printer 10 and information relating to the cartridge 100, and write the calculation result to the memory 110 as the identification information 131. Specifically, for example, the remaining amount 123 may be used as the information relating to the cartridge 100. In S15 and S16, the controller 30 multiplies the authentication information by the value of the remaining amount 123, and writes the result to the memory 110 as the identification information 131. For example, the EEPROM 46 stores a value of "2" as the authentication information. Also, for example, the remaining amount 123 is assumed to be "10." In this case, the identification information 131 becomes 20 (=2*10). In the simplified authentication process of S9 and S17, if the value obtained by dividing the specific information 131 read from the memory 110 by the authentication information value "2" matches the remaining amount 123, the controller 30 determines that the simplified authentication was successful (S17: YES), and if it does not match, it determines that the simplified authentication was unsuccessful (S17: NO).

[0084] The remaining amount 123 decreases due to printing, etc. Therefore, there is a risk that the authentication information and the identifying information 131 will become mismatched between when the main authentication is successful and the identifying information 131 is set and when the next main authentication is successful and the identifying information 131 is updated. In the above explanation, for ease of understanding, the value of the remaining amount 123 was used as "10." However, in reality, the value of the remaining amount 123 is managed as a decimal or binary value with several digits or several tens of digits. Therefore, only the most significant digits of the remaining amount 123 may be used as the value of the remaining amount 123 to be multiplied by the above-mentioned authentication information. This prevents the most significant digits from changing even if the remaining amount 123 decreases between when the main authentication is successful and the identifying information 131 is set and when the next main authentication is successful and the identifying information 131 is updated, thereby preventing the authentication information and the identifying information 131 from becoming mismatched.

[0085] Furthermore, the information related to the replacement part in this specification is not limited to the remaining amount 123, but may be other information such as the reset count 127, the ID information 128, or the identification information (UID) of the IC board 105. The above-described calculation formula is an example. For example, the controller 30 may store the value obtained by dividing the remaining amount 123 by the authentication information as the identification information 131. Furthermore, the controller 30 does not need to determine whether the calculation result based on the identification information 131 and the authentication information matches the information related to the replacement part (such as the remaining amount 123). For example, the controller 30 may execute a calculation based on the identification information 131 and the information related to the replacement part, and determine whether the calculation result matches the authentication information.

[0086] This (another simplified authentication process 2) can also be applied to the above-mentioned (another pattern 1 of identification information 131) and (another pattern 2 of identification information 131). Specifically, the controller 30 may perform a calculation using authentication information shared by a plurality of different printers 10 and information about the replacement part, and store the result of the calculation in the memory 110 as the identification information 131. Furthermore, the server may perform a calculation based on information about the replacement part acquired from the printer 10 and authentication information stored in the server, and transmit the result of the calculation to the printer 10 as the identification information 131.

[0087] (Another simple authentication process 3) As described above, the controller 30 causes the first logic circuit 132 of the IC substrate 105 to perform the calculation of the hash value required for the main authentication in S11. Furthermore, in S9, the controller 30 causes the second logic circuit 133 of the IC substrate 105 to perform the calculation required for the simplified authentication (the calculation to determine whether the serial numbers match). However, the use of the first logic circuit 132 and the second logic circuit 133 is not limited to this. For example, when performing a calculation based on the identifying information 131 as in the above-described (another simplified authentication process 1) for simplified authentication, the controller 30 may cause the second logic circuit 133 to perform this calculation. Alternatively, the controller 30 may cause the second logic circuit 133 to perform part of the calculation required for simplified authentication. Furthermore, the calculations for both the main authentication and the simplified authentication may be performed by a single logic circuit. Furthermore, a process requiring a shorter processing time than the main authentication process can be appropriately adopted as the simplified authentication process.

[0088] Incidentally, the relationship between the contents of this specification and the terminology in the first embodiment is as follows: In the above embodiment, the printer 10 is an example of a replacement part authentication device and an image forming apparatus. The mounting case 27 is an example of a mounting unit. The contacts 35 are an example of a connection unit. The EEPROM 46 is an example of a storage device. The network IF 51 is an example of a communication unit. The cartridge 100 is an example of a replacement part. The control program PG is an example of a program. The ink 101 is an example of a consumable material. The control unit 112 is an example of a processing unit.

[0089] As described above, the first embodiment provides the following effects. (1) The controller 30 of the printer 10 of this embodiment is capable of executing a main authentication process (S11) that authenticates the cartridge 100, and a simplified authentication process (S9) that authenticates the cartridge 100 and requires a shorter processing time than the main authentication process. The controller 30 executes the main authentication process of S11 for a cartridge 100 that has been attached to the attachment case 27 for the first time (S5: NO). Then, when executing authentication for a cartridge 100 that has been successfully authenticated by the main authentication process from the next time onwards, the controller 30 switches between the main authentication process and the simplified authentication process using at least one of a fixed probability, predetermined timing, randomly, and a variable probability that changes the probability depending on the success of the authentication (S7).

[0090] According to this, by employing a highly reliable authentication process as the main authentication process, the main authentication process is always performed on a new or refurbished cartridge 100 that is first attached to the attachment case 27, thereby restricting use to genuine cartridges 100 only. For example, by using a stronger encryption technology such as a longer encryption key or asymmetric encryption, it is possible to perform authentication with a high level of reliability and security, and more reliably prohibit the use of non-genuine cartridges 100 such as inferior counterfeits.

[0091] On the other hand, if the encryption and decryption calculations become more complex in order to increase the reliability of authentication, the processing time increases, resulting in delays to the start of printing, etc. Therefore, for cartridges 100 that have successfully passed the full authentication process and secured a certain level of reliability, the full authentication process and simplified authentication process are switched between for the next authentication and thereafter. This reduces the total processing time for the authentication process to authenticate the cartridge 100 compared to a configuration in which the full authentication process is executed every time. Furthermore, by performing main authentication on cartridges 100 that have been successfully authenticated, rather than simply performing simple authentication, a high level of reliability for the cartridges 100 can be maintained, and security for the cartridges 100 can be ensured.

[0092] (2) Furthermore, if the main authentication is successful (S12: YES), the controller 30 writes the identification information 131 to the memory 110 via the contact 35 (S16). In the simplified authentication process of S9, the controller 30 authenticates the cartridge 100 using the identification information 131 stored in the memory 110. According to this, if the main authentication is successful, the specific information 131 can be written to the memory 110 of the cartridge 100. By executing the simple authentication process using the specific information 131 written when the main authentication is successful, the reliability of the simple authentication can be increased.

[0093] (3) Furthermore, when the cartridge 100 is attached to the attachment case 27, the controller 30 determines whether or not the identification information 131 is stored in the memory 110 (S5, an example of the identification information determination process of this specification). If the controller 30 determines as a result of the process of S5 that the identification information 131 is not stored in the memory 110 (S5: NO), it executes the main authentication process of S11. Furthermore, if the identification information 131 is stored in the memory 110 (S5: YES), the controller 30 switches between the main authentication process and the simplified authentication process at a certain probability or the like and executes them (S7). This makes it possible to switch between performing the full authentication process and the simplified authentication process depending on whether the specific information 131 is stored in the memory 110 of the cartridge 100.

[0094] (4) The controller 30 also stores in the EEPROM 46 a main authentication required flag FG, which indicates whether or not the main authentication process needs to be executed. If the controller 30 determines to execute the main authentication process (S7: YES) while the specific information 131 is stored in the memory 110 (S5: YES), the controller 30 sets the main authentication required flag FG in the EEPROM 46 to ON (S8). Even if the specific information 131 is stored in the memory 110 (S5: YES), the controller 30 executes the main authentication process (S11) if the main authentication required flag FG is ON (S6: NO). If the main authentication is successful (S12: YES), the controller 30 sets the main authentication required flag FG to OFF (S13). The main authentication required flag FG remains in the state stored in the EEPROM 46, and the set ON / OFF value is maintained, even when the printer 10 is powered on or off or when the printer 10 settings are initialized.

[0095] With this, even if the specific information 131 is stored in the memory 110, once it is decided to execute the authentication process, the execution of the authentication process cannot be avoided even if the power of the printer 10 is turned on or off or the settings are initialized. This makes it possible to more reliably prevent the use of non-genuine cartridges 100.

[0096] (5) Furthermore, the controller 30 can detect the remaining amounts Vc and Vs based on the remaining amount Vs stored in the EEPROM 46, the remaining amount 123 stored in the memory 110, and the equilibrium calculation parameters 129. If the remaining amount 123 of the ink 101 is equal to or less than a predetermined threshold (S1: NO), the controller 30 does not execute either the full authentication process or the simplified authentication process, and does not permit use of the cartridge 100 (S3).

[0097] If the remaining amount 123 of the cartridge 100 is below a predetermined threshold, for example, if the remaining amount 123 is zero, the cartridge 100 cannot be used effectively even if authentication is successful. Therefore, by determining the remaining amount 123 (remaining amount Vc) of ink 101 in the cartridge 100 before executing the full authentication process or simplified authentication process, it is possible to avoid executing unnecessary authentication processes. The detection unit in this specification, i.e., the method for detecting the remaining amount of consumables, is not limited to the method in which the controller 30 performs calculations using the equilibrium calculation parameters 129, etc. For example, the printer 10 may be provided with a liquid level sensor as a detection unit that detects the height of the liquid surface of the first ink 101A in the cartridge 100, and the remaining amount 123 may be detected by the liquid level sensor.

[0098] (6) The memory 110 also stores cartridge type information 125, which includes information on the type of ink 101 (color in the first embodiment) and information on the destination of the cartridge 100. The controller 30 acquires the cartridge type information 125 from the memory 110 via the contacts 35, and if at least one of the type of ink 101 and the destination of the cartridge 100 is inappropriate (S1: NO), the controller 30 does not execute either the full authentication process or the simplified authentication process, and does not permit use of the cartridge 100 (S3).

[0099] If the type of ink 101 is inappropriate, for example, if the color of the ink 101 or the installation position is incorrect, the cartridge 100 cannot be used even if authentication is successful. Also, if the destination of the cartridge 100 is incorrect, it is not desirable to allow it to be used as is. For this reason, by determining the type and destination of the ink 101 before executing the full authentication process or simplified authentication process, it is possible to avoid unnecessary authentication processes from being executed. It should be noted that the cartridge type information 125 may include at least one of information on the type of ink 101 and information on the destination of the cartridge 100, and the controller 30 may determine only at least one of the pieces of information in S1.

[0100] (7) The specific information 131 is information (such as a serial number) that indicates a unique value associated with the printer 10, and is a value that differs from the specific information 131 used by other printers 10. This increases the reliability of simplified authentication by using different identification information 131 for each printer 10. It also prevents the identification information 131 from being reused in printers 10 other than the printer 10 in which the identification information 131 was written.

[0101] (8) Furthermore, the identification information 131 may be information that is shared among a plurality of different printers 10 (another pattern 1 of the identification information 131 described above). The identification information 131 is information that allows a first printer 10 (printer A) to use the identification information 131 to successfully authenticate the cartridge 100 attached to its own device through a simplified authentication process, and also allows a second printer 10 (printer B) different from the first printer 10 to use the identification information 131 to successfully authenticate the cartridge 100 attached to its own device through a simplified authentication process.

[0102] This allows the same identification information 131 to be used between different printers 10. Therefore, when a cartridge 100 having identification information 131 written in printer A is installed in printer B, simplified authentication processing can be executed using that identification information 131.

[0103] (9) The printer 10 can also be connected to a server via the network IF 51. In this case, as described in Alternative Pattern 2 of the identification information 131 above, the identification information 131 and the identification information of the cartridge 100 may be stored in association with each other in the server. If authentication through this authentication process is successful, the controller 30 may transmit the identification information of the cartridge 100 attached to the mounting case 27 to the server via the network IF 51, and obtain from the server the identification information 131 associated with the transmitted identification information. The controller 30 may then write the identification information 131 obtained from the server to the memory 110.

[0104] This allows the identification information and specification information 131 of the cartridge 100 to be managed collectively by the server. This eliminates the need for processing in the printer 10 to manage the specification information 131. Furthermore, each printer 10 can inquire about the specification information 131 from the server and use it without depending on a specific printer 10.

[0105] (10) Furthermore, in the simplified authentication process of S9, if the specific information 131 is stored in the memory 110, the controller 30 determines that the authentication has been successful (S17: YES), and if the specific information 131 is not stored, the controller 30 determines that the authentication has failed (S17: NO). According to this, the success or failure of simplified authentication can be determined depending on whether or not the specific information 131 is stored in the memory 110 of the cartridge 100, and authentication can be performed at higher speed.

[0106] (11) In addition, in the simplified authentication process, the controller 30 may determine whether the specific information 131 stored in the memory 110 is correct based on the authentication information held by the printer 10 (another simplified authentication process 1 described above). If the correct specific information 131 is stored, the controller 30 may determine that the simplified authentication has been successful, and if incorrect specific information 131 is stored, the controller 30 may determine that the simplified authentication has failed. According to this, by determining whether the specific information 131 stored in the memory 110 of the cartridge 100 is correct using the authentication information, it is possible to determine whether the simplified authentication has been successful.

[0107] (12) Furthermore, in the above (11), if the main authentication is successful, the controller 30 may execute a calculation based on the authentication information held by the printer 10 and information about the cartridge 100 (such as the remaining amount 123), and write the calculation result to the memory 110 as the identification information 131 (the above-mentioned another simplified authentication process 2). Then, in the simplified authentication process, the controller 30 may determine whether the calculation result based on the identification information 131 and authentication information stored in the memory 110 matches the information about the cartridge 100, and if they match, determine that the simplified authentication was successful, and if they do not match, determine that the simplified authentication was unsuccessful.

[0108] According to this, when main authentication is successful, specific information 131 is calculated and written based on the authentication information and information about cartridge 100. Then, when simple authentication processing is executed, authentication can be performed by comparing the result of calculation based on specific information 131 in memory 110 and authentication information with information about the cartridge 100 currently installed.

[0109] (13) Furthermore, the calculations related to the simplified authentication process may be executed by the second logic circuit 133 of the control unit 112 (another simplified authentication process 3 described above). The cartridge 100 has a control unit 112 having first and second logic circuits 132, 133. The first logic circuit 132 executes the calculations related to the main authentication process (for example, calculation of a hash value). The second logic circuit 133 is a logic circuit different from the first logic circuit 132, and may execute the calculations related to the simplified authentication process without executing the calculations related to the main authentication process.

[0110] Logic circuits that perform various calculations are provided in the control unit 112 and IC substrate 105 of the cartridge 100. When performing the main authentication process, the control unit 112 can perform the calculations using a first logic circuit 132, and when performing the simplified authentication process, the control unit 112 can perform the calculations using a second logic circuit 133 that is different from the first logic circuit 132.

[0111] (14) Furthermore, when performing authentication on a cartridge 100 that has been successfully authenticated, the controller 30 switches between the main authentication process and the simplified authentication process with a preset probability. According to this, after the main authentication is successful, instead of only executing the simple authentication process, the main authentication process is executed with a certain probability, thereby increasing the reliability of the cartridge 100 and maintaining security.

[0112] (15) Furthermore, when performing subsequent authentication on a cartridge 100 that has been successfully authenticated using the main authentication process, the controller 30 may switch between the main authentication process and the simplified authentication process at a predetermined timing (the above-mentioned method of determining based on a predetermined timing). According to this, after the main authentication is successful, instead of only executing the simple authentication process, the main authentication process is executed at a predetermined timing, thereby increasing the reliability of the cartridge 100 and maintaining security.

[0113] (16) Furthermore, when the controller 30 performs subsequent authentication on a cartridge 100 that has successfully passed full authentication, the controller 30 may use a random number to randomly switch between full authentication processing and simplified authentication processing (the above-mentioned random number-based determination method). According to this, after the main authentication is successful, instead of only executing the simple authentication process, the main authentication process is executed randomly, thereby increasing the reliability of the cartridge 100 and maintaining security.

[0114] (17) Furthermore, the controller 30 may store in the EEPROM 46 the number of consecutive successful authentication attempts in at least one of the main authentication process and the simplified authentication process (method 1 for determining the variable probability described above). When performing subsequent authentication attempts on a cartridge 100 that has successfully passed main authentication, the controller 30 may change the probability depending on the success of the authentication by lowering the probability of executing the main authentication process in accordance with an increase in the number of successes stored in the EEPROM 46.

[0115] A user who has been using the cartridge for a long period of time after successful authentication is unlikely to purchase and use an inferior counterfeit cartridge 100. Therefore, by lowering the probability of executing the main authentication process as the number of consecutive successful authentication attempts in at least one of the main authentication process and the simplified authentication process increases, the total processing time for authentication can be further shortened and usability can be improved for users who continue to use the cartridge in the above-mentioned excellent manner.

[0116] (18) Furthermore, the controller 30 may execute this authentication process in response to replacement of the cartridge 100, and may change the probability in response to the success of the authentication by lowering the probability of executing this authentication process as multiple cartridges 100 are replaced and the number of cartridges 100 that have been successfully authenticated in the past increases (method 2 for determining variable probability above).

[0117] A user who has been able to replace the cartridge 100 and still be able to use the cartridge for a long period of time after successful authentication is unlikely to purchase and use an inferior counterfeit cartridge 100. Therefore, by lowering the probability of executing the authentication process as the number of times the cartridge 100 is replaced and the authentication process is successful increases, the total processing time for authentication can be further shortened and usability can be improved for users who continue to use the cartridge in the above-mentioned good manner.

[0118] (19) Furthermore, the cartridge 100 can be remanufactured after use and reused in the printer 10 as a remanufactured product. A reset count 127, which indicates the number of times the cartridge 100 having the memory 110 has been remanufactured, is stored in the memory 110 of the cartridge 100. When performing subsequent authentication on a cartridge 100 that has successfully passed main authentication, the controller 30 may change the probability of executing the main authentication process in accordance with an increase in the reset count 127 stored in the memory 110, thereby changing the probability depending on whether the authentication is successful (method 3 for determining variable probability above).

[0119] A cartridge 100 that has been repeatedly played is highly likely to be genuine. Therefore, by lowering the probability of executing this authentication process as the reset count 127 (number of times played) stored in the memory 110 of the cartridge 100 increases, the total processing time for authentication can be further reduced for cartridges 100 that are highly likely to be genuine.

[0120] (20) Furthermore, when the controller 30 succeeds in the authentication and writes the specific information 131 to the memory 110 via the contact 35, if another specific information 131 is already stored in the memory 110, the controller 30 overwrites the other specific information 131 stored therein with the new specific information 131 (S16). According to this, by overwriting the specific information 131 in the memory 110, the storage capacity that needs to be secured in the memory 110 to store the specific information 131 can be reduced.

[0121] (21) Furthermore, when the controller 30 writes specific information 131 to the memory 110, if another specific information 131 is already stored in the memory 110, the controller 30 may store the new specific information 131 in the memory 110 while leaving the other specific information 131 stored therein. This allows past identification information 131 to be stored in memory 110. When cartridge 100 is replaced, if it is a cartridge 100 that has been previously installed and has identification information 131 written to it, simple authentication processing can be performed using the written identification information 131 without newly storing identification information 131. Unnecessary writing processing can be omitted.

[0122] (Second embodiment) Next, a second embodiment of the present specification will be described. In the first embodiment described above, the controller 30 determined in S7 whether to execute the main authentication process or the simplified authentication process based on the specific information 131 written in the memory 110 of the cartridge 100 by the controller 30. In contrast, the controller 30A of the second embodiment stores information about cartridges 100 that have successfully passed main authentication as an authentication success history DT in the EEPROM 46 of the printer 10A, and determines S7 based on the stored authentication success history DT, which is different from the first embodiment. In the following description of the second embodiment, the same reference numerals are used to designate the same parts as in the first embodiment, and their description will be omitted where appropriate.

[0123] Fig. 8 shows a block diagram of a printer 10A according to the second embodiment. As shown in Fig. 8, in the printer 10A according to the second embodiment, an authentication success history DT is stored in the EEPROM 46 of the controller 30A. The storage destination of the authentication success history DT is not limited to the EEPROM 46, but may also be the ROM 44, an external storage medium connected to the printer 10A, network storage, or a server. Therefore, the authentication success history DT may be stored in a device separate from the image forming device.

[0124] Fig. 9 shows the cartridge authentication process of the second embodiment. As in the first embodiment, when the cartridge 100 is replaced, the controller 30A starts the process of Fig. 9, and if an affirmative determination is made in S1 (S1: YES), the controller 30A of the second embodiment executes S6. Therefore, unlike the controller 30 of the first embodiment, the controller 30A of the second embodiment does not execute processes such as obtaining the identification information 131 (S2, S5, etc. of Fig. 5).

[0125] If the authentication required flag FG is off (S6: YES), the controller 30A executes S21. In S21, the controller 30A acquires the authentication success history DT from the EEPROM 46. Then, based on the authentication success history DT acquired in S21, the controller 30A determines whether to execute the main authentication process or the simplified authentication process (S7).

[0126] When the controller 30A executes the main authentication process (S7: YES), it turns on the authentication mandatory flag FG (S8), executes the main authentication process (S11), and determines whether the main authentication is successful (S12), as in the first embodiment. When the main authentication is successful (S12: YES), the controller 30A turns off the authentication mandatory flag FG (S13), and then updates the authentication success history DT (S22).

[0127] In S22, the controller 30A stores information about the cartridge 100 that has successfully passed main authentication (such as a replaced cartridge 100) in the authentication success history DT. The information about the cartridge 100 may include, for example, the identification information (substrate ID) of the IC substrate 105, the ID information 128 of the memory 110, the reset count 127, the remaining amount 123, and the cartridge type information 125 (color and destination of the ink 101). The information about the cartridge 100 is not limited to the information described above, and may include, for example, the manufacturing date and time of the cartridge 100 and the number of times the memory 110 has been written. The information about the cartridge 100 may also include the number of times main authentication has succeeded, the date and time when main authentication has succeeded, and the date and time when simplified authentication has succeeded. Therefore, the information about the cartridge 100 may include information that can identify the cartridge 100 and information that serves as a reference when determining whether or not main authentication should be performed.

[0128] After updating the authentication success history DT in S22, the controller 30A ends the processing shown in FIG. 9. Thereafter, the controller 30A starts the processing of FIG. 9 again in response to the execution of printing, etc., and when executing S7, makes a judgment based on the updated authentication success history DT. The controller 30A, for example, judges whether the board ID of the cartridge 100 to be authenticated is stored in the authentication success history DT (S7). If the board ID acquired from the cartridge 100 to be authenticated is stored in the authentication success history DT, the controller 30A judges to execute the simplified authentication process (S7: NO). In this case, the controller 30A executes the simplified authentication process for the cartridge 100 that has successfully passed the full authentication once, in subsequent authentications.

[0129] The above-described method of determination based on the authentication success history DT is one example. For example, instead of or in addition to the board ID, the controller 30A may also determine in S7 whether the ID information 128 or the reset count 127 matches. When determining the reset count 127, even if it is the same cartridge 100, it can be treated as a different cartridge 100 each time it is played, and this authentication process can be performed. Furthermore, the controller 30A may determine to execute the simplified authentication process if the board ID and the remaining amount 123 match (S7: NO). In this case, the main authentication process can be executed every time the amount of ink 101 changes. Furthermore, the controller 30A may store the board ID and the number of times the main authentication process has succeeded in the authentication success history DT, and determine the number of times it has succeeded in S7. For example, when the number of successes stored in the authentication success history DT reaches a predetermined number of times, the controller 30A executes the simplified authentication process (S7: NO) and resets the number of successes. This allows the simplified authentication process to be executed every time the main authentication has succeeded a predetermined number of times in a row. Alternatively, the controller 30A may store the board ID and the date and time when the main authentication was successful in the authentication success history DT, and determine the amount of time that has elapsed since the date and time when the main authentication was successful in S7. For example, the controller 30A determines to perform simple authentication if the amount of time that has elapsed since the date and time when the main authentication was successful is less than a reference time (S7: NO). Alternatively, the controller 30A determines to perform main authentication if the amount of time that has elapsed since the date and time when the main authentication was successful is equal to or greater than the reference time (S7: YES), and updates the date and time in the authentication success history DT according to the success of the main authentication (S22). This allows main authentication to be performed every time simple authentication is performed for the reference time.

[0130] Furthermore, in S22, the controller 30A may add information about the cartridge 100 that has been successfully authenticated to the authentication success history DT each time the main authentication of a new cartridge 100 is successful. Alternatively, the controller 30A may overwrite information about the cartridge 100 in the authentication success history DT each time the main authentication of a new cartridge 100 is successful. In this case, the authentication success history DT may store only information about one or a predetermined number of cartridges 100, and if main authentication of more than that number of cartridges 100 is successful, the oldest information may be overwritten. In this way, only information about a preset number of cartridges 100 is stored in the authentication success history DT, and the simplified authentication process can be performed on that number of cartridges 100 at the next authentication time.

[0131] The relationship between the contents of this specification and the terminology in the second embodiment is as follows: In the above embodiment, the printer 10A is an example of a replacement part authentication device and an image forming apparatus. The mounting case 27 is an example of a mounting unit. The EEPROM 46 is an example of a storage device. The cartridge 100 is an example of a replacement part.

[0132] As described above, the second embodiment provides the same effects as the first embodiment. Furthermore, the second embodiment provides the following effects. (1) The controller 30A of the second embodiment stores an authentication success history DT, which is information about the cartridge 100 that succeeded in the main authentication of S11, in the EEPROM 46 (S22). When performing authentication on the cartridge 100 attached to the attachment case 27, the controller 30A determines whether to perform the main authentication process or the simplified authentication process based on the authentication success history DT stored in the EEPROM 46 (S7).

[0133] According to this, by adopting a highly reliable authentication process as the main authentication process, the main authentication process is always executed for new or refurbished cartridges 100 that are attached to the attachment case 27 for the first time, thereby restricting use to genuine cartridges 100 only. Furthermore, for cartridges 100 that have successfully passed main authentication and secured a certain level of reliability, information about the cartridge 100 is stored in the authentication success history DT, and from the next authentication onwards, the main authentication process and simplified authentication process are switched between and executed based on the authentication success history DT. This makes it possible to reduce the processing time required for the authentication process of the cartridge 100 compared to a configuration in which the main authentication process is executed every time.

[0134] The present invention is not limited to the above-described embodiments, and various modifications are possible without departing from the spirit of the present invention. For example, the configurations of the printers 10 and 10A in the above embodiments are merely examples. The image forming apparatus in this specification is not limited to an inkjet image forming apparatus, but may also be an electrophotographic image forming apparatus. Therefore, the replaceable part in this specification is not limited to the cartridge 100 containing ink 101, but may also be a cartridge containing toner. Furthermore, the consumable material in this specification is not limited to ink 101, but may also be toner. In this case, the specific information 131 of the first embodiment may be stored in a memory provided in the toner cartridge, and it may be determined whether to perform full authentication or simplified authentication. The image forming apparatus in this specification may also be an apparatus that performs printing using other printing methods such as thermal transfer printing or thermal printing, etc. Therefore, the replacement parts and consumables in this specification may include ink ribbons, thermal paper, and components for storing them. Furthermore, the ink 101 may be stored in a container (such as a bottle) other than the cartridge 100. In this case, the container is an example of a replaceable part in this specification.

[0135] In the above embodiment, the printers 10 and 10A are used as the image forming apparatus in this specification, but this is not limiting. The image forming apparatus in this specification may also be a so-called "multifunction machine" that has functions such as a facsimile function, a scanning function, and a copying function. Furthermore, the printers 10 and 10A may not be provided with the subtank 37. Furthermore, the printers 10 and 10A may not have the network IF 51. The controller 30 may also include a SoC (System on a Chip) instead of or in addition to the ASIC 47. The controller 30 may also include a plurality of ASICs 47 and CPUs 43. The controller 30 may also be configured not to include a CPU 43, but to execute programs for controlling various operations in the ASIC 47. Furthermore, the replacement part authentication device of the present application is not limited to an image forming apparatus, and other devices in which replacement parts are replaced can be used. Specifically, a sewing machine, a laser marker, a machine tool, or the like can be used as the replacement part authentication device. Thread or needles from a sewing machine can also be used as replacement parts. A laser oscillation unit of a laser marker or a head that performs laser processing can also be used as replacement parts. Tools for machine tools can also be used as replacement parts.

[0136] Furthermore, the contents of this specification are not limited to the dependent relationships set forth in the claims. [Explanation of symbols]

[0137] 10,10A printer (replacement part authentication device, image forming apparatus), 27 mounting case (mounting part), 30,30A controller (detection part), 35 contact (connection part, detection part), 46 EEPROM (storage device), 51 network IF (communication part), 100 cartridge (replacement part), 101 ink (consumable), 110 memory, 112 control part (processing part), 123 remaining amount, 127 reset count, 131 specific information, 132 first logic circuit, 133 second logic circuit, DT authentication success history, FG authentication required flag, PG control program (program).

Claims

1. Replacement parts and a mounting portion to which the replacement part can be attached and detached; A controller; Equipped with The controller a main authentication process for authenticating the replacement part; a simplified authentication process for authenticating the replacement part, the simplified authentication process requiring a shorter processing time than the main authentication process; is executable, For the replacement part that is being attached to the attachment unit for the first time, the authentication process is performed. When performing subsequent authentication on a replacement part that has been successfully authenticated by the main authentication process, the replacement part authentication device switches between the main authentication process and the simplified authentication process using at least one of a fixed probability, a predetermined timing, randomness, and a variable probability that changes the probability depending on the success of the authentication.

2. The replacement part is having a memory, The mounting portion is a connection portion connected to the memory; The controller If the authentication by the authentication process is successful, write specific information into the memory via the connection unit; 2. The replacement part authentication device according to claim 1, wherein the simplified authentication process uses the specific information stored in the memory to authenticate the replacement part.

3. The controller When the replacement part is mounted in the mounting portion, a specific information determination process is executed to determine whether or not the specific information is stored in the memory; If it is determined that the specific information is not stored in the memory as a result of the specific information determination process, the authentication process is executed.

3. The replacement part authentication device of claim 2, wherein, if it is determined as a result of the specific information determination process that the specific information is stored in the memory, the authentication process and the simplified authentication process are switched between at least one of a fixed probability, a predetermined timing, randomness, and a variable probability that changes the probability depending on the success of the authentication.

4. The controller a main authentication required flag indicating whether or not the main authentication process needs to be executed can be stored in a storage device; When it is determined that the main authentication process is to be performed with the specific information stored in the memory, the main authentication required flag of the storage device is set to ON; Even if it is determined that the specific information is stored in the memory as a result of the specific information determination process, if the main authentication required flag is set to on, the main authentication process is executed, If the authentication in the authentication process is successful, the authentication required flag is set to off, The authentication required flag is 4. The replacement part authentication device according to claim 3, wherein the state stored in the storage device is maintained and the set on / off value is maintained even when the power supply of the replacement part authentication device is turned on / off and when the settings of the replacement part authentication device are initialized.

5. The replacement part is storing consumable materials consumed by the replacement part authentication device; The replacement part authentication device a detector that detects the remaining amount of the consumables contained in the replacement part; The controller 3. The replacement part authentication device according to claim 1, wherein, when the detection unit detects that the remaining amount of the consumable is below a predetermined threshold, neither the main authentication process nor the simplified authentication process is performed, and the use of the replacement part is not permitted.

6. The replacement part is having a memory, storing consumable materials consumed by the replacement part authentication device; The memory includes: At least one of information on the type of the consumables and information on the destination of the replacement part is stored; The mounting portion is a connection portion connected to the memory; The controller 3. The replacement part authentication device according to claim 1, wherein the information of the memory is acquired via the connection unit, and if at least one of the type of consumable material and the destination of the replacement part is inappropriate, the authentication process and the simplified authentication process are not performed, and the use of the replacement part is not permitted.

7. The specific information is 3. The replacement part authentication device according to claim 2, wherein the information indicates a unique value associated with the replacement part authentication device, and the value is different from specific information used by other replacement part authentication devices.

8. The specific information is information shared among a plurality of different replacement part authentication devices, In the first replacement part authentication device, the identification information is used to successfully authenticate the replacement part attached to the device through the simplified authentication process, The replacement part authentication device of claim 2, wherein the specific information is information that can be used by a second replacement part authentication device different from the first replacement part authentication device to successfully authenticate the replacement part attached to the device using the simplified authentication process.

9. Further comprising a communication unit connectable to a server, The server storing the specific information and the identification information of the replacement part in association with each other; The controller 3. The replacement part authentication device according to claim 2, wherein, if authentication by the authentication process is successful, the identification information of the replacement part mounted in the mounting unit is transmitted to the server via the communication unit, the specific information associated with the transmitted identification information is obtained from the server, and the specific information obtained from the server is written to the memory.

10. The controller 3. The replacement part authentication device according to claim 2, wherein, in the simplified authentication process, if the specific information is stored in the memory, it is determined that authentication has been successful, and if the specific information is not stored in the memory, it is determined that authentication has failed.

11. The controller 3. The replacement part authentication device according to claim 2, wherein in the simplified authentication process, it is determined whether the specific information stored in the memory is correct based on authentication information possessed by the replacement part authentication device, and if correct specific information is stored, it is determined that authentication has been successful, and if incorrect specific information is stored, it is determined that authentication has failed.

12. The controller If the authentication by the authentication process is successful, a calculation is performed based on the authentication information held by the replacement part authentication device and information related to the replacement part, and the calculation result is written to the memory as the identification information; 12. The replacement part authentication device according to claim 11, wherein in the simplified authentication process, it is determined whether or not a calculation result based on the specific information and the authentication information stored in the memory matches information about the replacement part, and if they match, it is determined that authentication has been successful, and if they do not match, it is determined that authentication has failed.

13. The replacement part is a processing unit having a plurality of logic circuits; The plurality of logic circuits include a first logic circuit that executes calculations related to the authentication process; a second logic circuit that is different from the first logic circuit and does not perform a calculation related to the main authentication process but performs a calculation related to the simplified authentication process; 3. The replacement part authentication device according to claim 1, further comprising:

14. The controller 3. The replacement part authentication device according to claim 1, wherein when performing authentication on a replacement part that has been successfully authenticated by the main authentication process, the device switches between the main authentication process and the simplified authentication process with a predetermined probability when performing authentication on the replacement part from the next time onward.

15. The controller 3. The replacement part authentication device according to claim 1, wherein when performing subsequent authentication on a replacement part that has been successfully authenticated by the main authentication process, the main authentication process and the simplified authentication process are switched between at a preset timing.

16. The controller 3. The replacement part authentication device according to claim 1, wherein when performing subsequent authentication on a replacement part that has been successfully authenticated by the main authentication process, the device randomly switches between the main authentication process and the simplified authentication process using a random number.

17. The controller storing the number of consecutive successful authentication attempts in at least one of the main authentication process and the simplified authentication process in a storage device; 3. The replacement part authentication device according to claim 1, wherein when performing subsequent authentication on a replacement part that has been successfully authenticated by the main authentication process, the probability of executing the main authentication process is lowered in accordance with an increase in the number of successes stored in the storage device, thereby changing the probability in accordance with the success of the authentication.

18. The controller Execute the authentication process in response to the replacement of the replacement part; 3. The replacement part authentication device according to claim 1, wherein the probability of executing the authentication process is reduced as the number of replacement parts that have been successfully authenticated by the authentication process in the past increases when multiple replacement parts are replaced, thereby changing the probability according to the success of the authentication.

19. The replacement part is The replacement part after use can be regenerated and reused as a regenerated product by the replacement part authentication device, The replacement part is having a memory, The memory includes: a reset count, which is the number of times the replacement part having the memory has been remanufactured, is stored; The controller 3. The replacement part authentication device according to claim 1, wherein when performing authentication on a replacement part that has been successfully authenticated by the main authentication process, the probability of executing the main authentication process is lowered in accordance with an increase in the reset count stored in the memory, thereby changing the probability in accordance with the success of the authentication.

20. The controller 3. The replacement part authentication device of claim 2, wherein when authentication by the authentication process is successful and specific information is written to the memory via the connection unit, if other specific information is already stored in the memory, the stored other specific information is overwritten with the new specific information.

21. The controller 3. The replacement part authentication device of claim 2, wherein when authentication by the authentication process is successful and specific information is written to the memory via the connection unit, if other specific information is already stored in the memory, the new specific information is stored in the memory while leaving the other specific information stored.

22. Replacement parts and a mounting portion to which the replacement part can be attached and detached; A controller; Equipped with The controller a main authentication process for authenticating the replacement part; a simplified authentication process for authenticating the replacement part, the simplified authentication process requiring a shorter processing time than the main authentication process; is executable, storing an authentication success history, which is information about the replacement part that has been successfully authenticated by the authentication process, in a storage device; A replacement part authentication device that, when performing authentication of the replacement part attached to the attachment section, determines whether to perform the full authentication process or the simplified authentication process based on the authentication success history stored in the storage device.

23. The replacement part authentication device according to claim 1 or 2; an image forming unit; Equipped with The replacement part is storing consumables consumed by the image forming unit; The controller 3. The image forming apparatus according to claim 1, wherein the replacement part that has been successfully authenticated in the main authentication process is subjected to subsequent authentication in response to image formation by the image forming unit.

24. Replacement parts and a mounting portion to which the replacement part can be attached and detached; A program executed by a computer of a replacement part authentication device comprising: The computer, a main authentication process for authenticating the replacement part; a simplified authentication process for authenticating the replacement part, the simplified authentication process requiring a shorter processing time than the main authentication process; Execute For the replacement part that is being attached to the attachment unit for the first time, the authentication process is executed; a program that, when performing authentication on the replacement part that has been successfully authenticated by the main authentication process from the next time onward, switches between the main authentication process and the simplified authentication process with at least one of a fixed probability, a predetermined timing, randomly, and a variable probability that changes the probability depending on the success of the authentication.

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