JP2012125958A - Printer and printing material cartridge - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a technique capable of performing installation detection on printing material cartridges by a means different from a conventional one.SOLUTION: The printer includes a holder and an installation detecting circuit for detecting installation states of cartridges. Each of the cartridges includes a storage device for storing information on a printing material, an electric device for installation detection, a terminal for the storage device, and a terminal for the electric device. The electric device includes a variable resistance circuit which attains a respectively different resistance value in each of N printing material cartridges by selectively taking one of a plurality of resistance values according to selection information preliminarily stored in the storage device. The variable resistance circuits of the N printing material cartridges are connected in parallel between a power source for installation detection and an installation current value detection unit, and are constituted so that a detecting current has a current value capable of uniquely discriminating 2types of installation states on the printing material cartridges when all the N printing material cartridges are installed.

Description

  The present invention relates to a printing apparatus in which a printing material cartridge can be mounted, and a printing material cartridge.

  In recent years, as a printing material cartridge, a cartridge equipped with a storage device that stores information about the printing material (for example, remaining ink amount) is used. In addition, a technique for detecting mounting of a printing material cartridge is also used. For example, in Patent Document 1, a CPU of a printing apparatus detects whether or not an ink cartridge is mounted by communicating with a storage device of the ink cartridge.

  However, in the technique of Patent Document 1, if the user tries to detect the mounting while the ink cartridge is being replaced, the ink cartridge needs to be detached while the cartridge storage device is energized. In this case, since hot insertion / removal of the storage device is performed, there is a possibility that stress is applied to the semiconductor elements in the storage device and induces bit errors. On the other hand, to prevent such bit errors, if the CPU does not access the cartridge storage device during the ink cartridge replacement operation, which cartridge is not mounted on the display panel of the printing device during the replacement operation. It is impossible to notify the user by displaying whether it is, and there is a problem that the convenience of the user is greatly impaired.

  An ink cartridge mounting detection technique described in Patent Document 2 is also known. In the technique of Patent Document 2, the mounting detection circuit of the printing apparatus determines whether or not the ink cartridge is mounted by detecting a voltage that changes according to the ink resistance value in the ink cartridge. However, in this technique, in order to detect whether or not each of the plurality of ink cartridges is mounted, wiring for mounting detection is individually installed between each cartridge and the mounting detection circuit of the printing apparatus. There was a problem that it was necessary.

  Note that the above-described problem is not limited to the ink cartridge, but also applies to a printing material cartridge containing another type of printing material (for example, toner).

JP 2005-119228 A Japanese Patent Laid-Open No. 3-284953

  An object of the present invention is to provide a technique capable of detecting mounting of a printing material cartridge by means different from the conventional one.

  SUMMARY An advantage of some aspects of the invention is to solve at least a part of the problems described above, and the invention can be implemented as the following forms or application examples.

[Application Example 1]
A printing device,
A holder on which different N (N is an integer of 2 or more) printing material cartridges that can be mounted independently from each other;
A power supply for mounting detection; and a mounting current value detection unit that detects a detection current that flows when one or more printing material cartridges are mounted in the holder, and the N printing materials according to the detected current A mounting detection circuit for detecting the mounting state of the cartridge;
With
Each of the N printing material cartridges includes a storage device for storing information about the stored printing material, an electrical device for mounting detection, a terminal for the storage device, and a terminal for the electrical device. And
The electrical device of the N printing material cartridges selectively takes one of a plurality of resistance values in accordance with selection information stored in advance in the storage device, whereby the N printing materials. It has a variable resistance circuit that realizes different resistance values in the cartridge,
The variable resistance circuits of the N printing material cartridges are:
(I) Connected in parallel between the mounting detection power source and the mounting current value detection unit,
(Ii) When all the N printing material cartridges are mounted in the holder, the detected current detected by the mounting current value detection unit indicates 2 ^N types of mounting states related to the ^N printing material cartridges. A printing device configured to take a uniquely identifiable current value.
According to this printing apparatus, the detection current is determined according to the mounting state of the electrical device for mounting detection provided separately from the storage device, and all the N printing material cartridges are mounted in the holder. Sometimes this detected current takes a uniquely identifiable current value determined according to 2 ^N types of mounting states, and from this detected current, the mounting state of the printing material cartridge in the holder is any of the 2 ^N types of mounting states. It is possible to determine whether there is. In addition, when detecting the mounting of the printing material cartridge, there is no need to worry about bit errors due to hot-swapping of the storage device.

[Application Example 2]
A printing apparatus according to Application Example 1,
The variable resistance circuit of the nth (n = 1 to N) printing material cartridge among the N printing material cartridges is connected in parallel between the mounting detection power source and the mounting current value detection unit. A resistance for mounting detection is formed alone or in series connection with other resistance elements provided in the mounting detection circuit,
The mounting detection resistance for the nth printing material cartridge is 2 ⁿ R (1 when R is a constant value and the tolerance ε is 1 / {4 (2 ^N−1 −1)}. A printing device configured to have a resistance value within a range of ± ε).
According to this configuration, even when there is an allowable range error in each resistance value, 2 ^N types of mounting states can be identified from the detected current.

[Application Example 3]
A printing apparatus according to Application Example 2,
The mounting current value detection unit
A current-voltage converter that generates a detection voltage by converting the detection current into a voltage;
An AD converter for sequentially comparing the mounting detection voltage with a plurality of threshold voltages and converting the detected voltage into a digital detection signal;
A voltage correction unit that corrects the plurality of threshold voltages by following a change in voltage of the power supply for mounting detection;
With
The mounting detection circuit determines a mounting state of a printing material cartridge in the holder based on the digital detection signal.
According to this configuration, the threshold voltage used when converting the detection current into the digital detection signal is adjusted so as to follow the voltage of the mounting detection power supply, so the voltage of the mounting detection power supply fluctuates. Even so, it is possible to accurately detect the wearing state.

[Application Example 4]
The printing apparatus according to any one of Application Examples 1 to 3,
A voltage higher than the voltage applied to the storage device terminal is supplied from the mounting detection power source to the electrical device terminals of the N printing material cartridges,
Each of the N printing material cartridges further has an overvoltage detection terminal provided in the vicinity of the terminal for the electric device,
The mounting detection circuit stops a supply of voltage from the mounting detection power source to the electric device when an overvoltage is detected via the overvoltage detection terminal.
According to this configuration, when an unintentional short circuit occurs due to foreign matter such as ink or dust between the electrical device terminal and the overvoltage detection terminal, it can be immediately detected as an overvoltage. Thus, it is possible to reduce the possibility that the high voltage for mounting detection is applied to other circuits to cause damage.

[Application Example 5]
A power supply for mounting detection; and a mounting current value detection unit that detects a detection current that flows when one or more printing material cartridges are mounted in a holder of a printing apparatus, and the printing material in the holder is in accordance with the detected current A printing material cartridge mounted in the holder of the printing apparatus including a mounting detection circuit for detecting a mounting state of the cartridge,
The printing material cartridge includes a storage device for storing information relating to the stored printing material, an electrical device for mounting detection, a terminal for the storage device, and a terminal for the electrical device. And
The electrical device includes a variable resistance circuit that selectively takes one of a plurality of resistance values according to selection information stored in advance in the storage device,
The variable resistance circuit is:
(I) Connected in parallel between the mounting detection power source and the mounting current value detection unit,
(Ii) When all N printing material cartridges (N is an integer of 2 or more) that can be mounted in the holder are mounted, the detected current detected by the mounting current value detection unit is the N printings. A printing material cartridge configured to take a current value capable of uniquely identifying 2 ^N types of mounting states related to the material cartridge.
According to this printing material cartridge, the detection current is determined according to the mounting state of the electrical device for mounting detection provided separately from the storage device, and all the N printing material cartridges are mounted in the holder. When this occurs, the detected current takes a uniquely identifiable current value determined according to the 2 ^N types of mounting states. Therefore, from this detected current, the mounting state of the printing material cartridge in the holder is any of the 2 ^N types of mounting states. It is possible to determine whether or not. In addition, when detecting the mounting of the printing material cartridge, there is no need to worry about bit errors due to hot-swapping of the storage device.

[Application Example 6]
A printing material cartridge according to Application Example 5,
The electrical device is a resistive element;
The resistance element includes a mounting detection resistor connected in parallel between the mounting detection power source and the mounting current value detection unit, either alone or in series with another resistance element provided in the mounting detection circuit. Formed with connections,
Of the N printing material cartridges mounted in the holder, the mounting detection resistance for the nth (n = 1 to N) printing material cartridge has a constant value R and an allowable error ε of 1 /. A printing material cartridge configured to have a resistance value in a range of 2 ⁿ R (1 ± ε) when {4 (2 ^N-1 -1)}.
According to this configuration, even when there is an allowable range error in each resistance value, 2 ^N types of mounting states can be identified from the detected current.

  The present invention can be realized in various forms, for example, a printing material cartridge, a printing material cartridge set including a plurality of types of printing material cartridges, a cartridge adapter, and a plurality of types of cartridge adapters. It can be realized in the form of a cartridge adapter set, a printing device, a printing material cartridge mounting detection method, and the like.

1 is a perspective view illustrating a configuration of a printing apparatus according to an embodiment of the present invention. FIG. 3 is a perspective view illustrating a configuration of an ink cartridge according to the embodiment. The figure which shows the structure of the board | substrate which concerns on embodiment. FIG. 3 is a block diagram illustrating an electrical configuration of the ink cartridge and the printing apparatus according to the first embodiment. The figure which shows the internal structure of the memory | storage device and variable resistance circuit in 1st Embodiment. Explanatory drawing which shows the content of the mounting | wearing detection process of a cartridge. FIG. 9 is a block diagram illustrating an electrical configuration of an ink cartridge and a printing apparatus according to a second embodiment. The figure which shows the internal structure of the cartridge detection circuit in 2nd Embodiment. The flowchart which shows the whole procedure of a mounting | wearing detection process. The flowchart which shows the detailed procedure of a mounting | wearing detection process. The circuit diagram which shows the other structural example of a mounting | wearing detection circuit. The circuit diagram which shows the other structural example of a mounting | wearing detection circuit. The figure which shows the internal structure of the cartridge detection circuit in 3rd Embodiment. The figure which shows the internal structure of the separate mounting current value detection part in 3rd Embodiment. The figure which shows the structure of the separate mounting | wearing electric current value detection part in 4th Embodiment. The figure which shows the structure of the board | substrate which concerns on other embodiment. The perspective view which shows the structure of the ink cartridge in other embodiment. The perspective view which shows the structure of the ink cartridge in other embodiment.

A. First embodiment:
FIG. 1 is a perspective view illustrating a configuration of a printing apparatus according to an embodiment of the present invention. The printing apparatus 1000 has a sub-scan feed mechanism, a main scan feed mechanism, and a head drive mechanism. The sub-scan feed mechanism transports the printing paper P in the sub-scan direction using a paper feed roller 10 powered by a paper feed motor (not shown). The main scanning feed mechanism uses the power of the carriage motor 2 to reciprocate the carriage 3 connected to the drive belt in the main scanning direction. The head drive mechanism drives the print head 5 provided in the carriage 3 to execute ink ejection and dot formation. The printing apparatus 1000 further includes a main control circuit 40 that controls each mechanism described above. The main control circuit 40 is connected to the carriage 3 via the flexible cable 37.

  The carriage 3 includes a holder 4, a print head 5, and a carriage circuit (described later). The holder 4 is configured to be capable of mounting a plurality of ink cartridges, and is disposed on the upper surface of the print head 5. In the example shown in FIG. 1, four ink cartridges can be mounted independently on the holder 4. For example, four types of ink cartridges of black, yellow, magenta, and cyan are mounted one by one. Note that the holder 4 may be configured to be capable of mounting a plurality of arbitrary types of ink cartridges. A cover 11 is attached to the holder 4 so that it can be opened and closed. An ink supply needle 6 for supplying ink from the ink cartridge to the print head 5 is disposed above the print head 5.

  FIG. 2 is a perspective view illustrating the configuration of the ink cartridge according to the embodiment. The ink cartridge 100 includes a casing 101 that stores ink, and a substrate 200 (also referred to as a “circuit board”). An ink chamber 120 that stores ink is formed inside the housing 101. An ink supply port 110 into which the ink supply needle 6 of the printing apparatus is inserted when the holder 4 is mounted is formed on the bottom surface of the housing 101. In a state before use, the opening of the ink supply port 110 is sealed with a film. The ink cartridge 100 and the carriage 3 are provided with a sensor mechanism for optically detecting the remaining amount of ink in the ink cartridge 100, but the illustration is omitted here. Hereinafter, the ink cartridge is also simply referred to as “cartridge”.

  FIG. 3A shows the configuration of the surface of the substrate 200. The surface of the substrate 200 is a surface exposed to the outside when mounted on the cartridge 100. FIG. 3B shows the substrate 200 viewed from the side. A boss groove 201 for fixing the substrate is formed at the upper end portion of the substrate 200, and a boss hole 202 is formed at the lower end portion of the substrate 200.

  An arrow Z in FIG. 3A indicates the insertion direction of the cartridge 100 into the holder 4. The substrate 200 includes a storage device 203 on the back surface and a terminal group including nine terminals 210 to 290 on the front surface. The storage device 203 stores information regarding the remaining amount of ink in the cartridge 100. The terminals 210 to 290 are formed in a substantially rectangular shape and are arranged so as to form two rows substantially perpendicular to the insertion direction Z. Of the two rows, the row located on the insertion direction Z side, that is, the lower side in FIG. 3A is referred to as the lower row, and is located on the opposite side of the insertion direction Z, that is, the upper side in FIG. The column to be called is called the upper column.

The terminals 210 to 240 forming the upper row and the terminals 250 to 290 forming the lower row are arranged in the following order, respectively.
<Upper row>
(1) First overvoltage detection terminal 210
(2) Reset terminal 220
(3) Clock terminal 230
(4) Second overvoltage detection terminal 240
<Lower row>
(5) First mounting detection terminal 250
(6) Power supply terminal 260
(7) Ground terminal 270
(8) Data terminal 280
(9) Second mounting detection terminal 290

  Each terminal 210 to 290 includes a contact portion cp that comes into contact with a corresponding terminal among the plurality of device-side terminals at the center thereof. The contact portions cp of the terminals 210 to 240 forming the upper row and the contact portions cp of the terminals 250 to 290 forming the lower row are alternately arranged to form a so-called staggered arrangement. In addition, the terminals 210 to 240 forming the upper row and the terminals 250 to 290 forming the lower row are also arranged in a staggered manner so that the terminal centers are not aligned in the insertion direction Z. is doing.

  The first attachment detection terminal 250 is adjacent to two terminals (the power supply terminal 260 and the first overvoltage detection terminal 210), and the first overvoltage detection terminal 210 is the first attachment detection terminal. It is located in the vicinity of 250, and is particularly disposed at a position closest to the first mounting detection terminal 250. Similarly, the second attachment detection terminal 290 is adjacent to the two terminals (the second overvoltage detection terminal 240 and the data terminal 280), and the second overvoltage detection terminal 240 is the second one. Is located in the vicinity of the second mounting detection terminal 290, particularly at the position closest to the second mounting detection terminal 290.

  Looking at the relationship between the contact portions cp, the contact portion cp of the first mounting detection terminal 250 is adjacent to the contact portions cp of the two terminals (the power supply terminal 260 and the first overvoltage detection terminal 210). . Similarly, the contact portion cp of the second mounting detection terminal 290 is adjacent to each contact portion cp of the two terminals (the second overvoltage detection terminal 240 and the data terminal 280).

  As can be seen from FIG. 3A, the first and second attachment detection terminals 250 and 290 are respectively disposed at both ends of the lower row, that is, at the outermost side of the lower row. The lower row has more terminals than the upper row, and the length of the lower row in the direction substantially perpendicular to the insertion direction Z is longer than the length of the upper row. Accordingly, the first and second attachment detection terminals 250 and 290 are located on the outermost side in the direction substantially perpendicular to the insertion direction Z among all the terminals 210 to 290 including the upper row and the lower row.

  The contact portions cp of the first and second mounting detection terminals 250 and 290 are located at both ends of the lower row formed by the contact portions cp of the respective terminals, that is, at the outermost sides of the lower row. Yes. Further, the contact portions cp of the first and second mounting detection terminals 250 and 290 are viewed in a direction substantially perpendicular to the insertion direction Z among the contact portions cp of all the terminals 210 to 290 including the upper row and the lower row. Is located on the outermost side.

  The first and second overvoltage detection terminals 210 and 240 are respectively disposed at both ends of the upper row, that is, at the outermost side of the upper row. As a result, the contact portions cp of the first and second overvoltage detection terminals 210 and 240 are similarly located at both ends of the upper row formed by the contact portions cp of the respective terminals, that is, the outermost portions. Therefore, the terminals 220, 230, 260, 270, and 280 for the storage device 203 include the pair of the first overvoltage detection terminal 210 and the first mounting detection terminal 250, the second overvoltage detection terminal 240 and the second mounting. It arrange | positions so that it may be pinched | interposed into the detection terminal 290 pair from both sides.

  FIG. 4 is a block diagram illustrating an electrical configuration of the ink cartridge 100 and the printing apparatus 1000 according to the first embodiment. The printing apparatus 1000 includes a display panel 30, a main control circuit 40, a power supply circuit 440, and a carriage circuit 500. The display panel 30 is a display unit for performing various notifications such as an operation state of the printing apparatus 1000 and a cartridge mounting state to the user. The main control circuit 40 has a CPU 410 and a memory 420. The power supply circuit 440 includes a first power supply 441 that generates a first power supply voltage VDD, and a second power supply 442 that generates a second power supply voltage VHV. The first power supply voltage VDD is a normal power supply voltage (rated 3.3 V) used in the logic circuit. The second power supply voltage VHV is a high voltage (for example, rated 42 V) used for driving the print head to eject ink. These voltages VDD and VHV are supplied to the sub-control circuit 500, and are also supplied to other circuits as necessary. The carriage circuit 500 includes a memory control circuit 501 and a mounting detection circuit 600.

  Of the nine terminals provided on the substrate 200 (FIG. 3A) of the cartridge 100, the reset terminal 220, the clock terminal 230, the power terminal 260, the ground terminal 270, and the data terminal 280 are included in the storage device 203. Is electrically connected. The storage device 203 includes, for example, a serially accessed memory cell array (not shown), and is a non-volatile memory that reads and writes data in synchronization with the clock signal SCK. The clock terminal 230 is electrically connected to the terminal 530 of the carriage circuit 500 and is used to supply the clock signal SCK from the carriage circuit 500 to the storage device 203. A power supply voltage (for example, a rating of 3.3 V) and a ground voltage (0 V) are respectively supplied to the power supply terminal 260 and the ground terminal 270 via the terminals 560 and 570 on the printing apparatus 1000 side. The data terminal 280 is electrically connected to the terminal 580 of the carriage circuit 500 and is used for exchanging the data signal SDA between the carriage circuit 500 and the storage device 203. The reset terminal 220 is electrically connected to the terminal 520 of the carriage circuit 500 and is used to supply a reset signal RST from the carriage circuit 500 to the storage device 203.

  The first and second overvoltage detection terminals 210 and 240 are connected by wiring in the substrate 200 of the cartridge 100 (FIG. 3A), and are electrically connected to the terminals 510 and 540 of the carriage circuit 500, respectively. Connected. The state in which the two terminals are connected by wiring is also referred to as “short-circuit connection” or “conductor connection”. A short-circuit connection by wiring is different from an unintended short circuit. The overvoltage detection terminals 210, 240, 510 and 540 can be omitted. The first and second mounting detection terminals 250 and 290 are provided with a variable resistance circuit 300 for mounting detection therebetween, and are electrically connected to terminals 550 and 590 of the carriage circuit 500, respectively.

  Wiring names SCK, VDD, SDA, RST, OV1, OV2, DT1, and DT2 are attached to wirings that connect the device side terminals 510 to 590 and the terminals 210 to 290 of the substrate 200, respectively. Of these wiring names, the same names as the signal names are used for wiring for the storage device.

  The memory control circuit 501 is a circuit that controls the storage device 203 of the cartridge 100 to read and write data. The memory control circuit 501 and the cartridge storage device 203 are low voltage circuits that operate at a relatively low voltage (in this embodiment, a rating of 3.3 V).

  The mounting detection circuit 600 is a circuit for performing mounting detection of the cartridge in the holder 4. The mounting detection circuit 600 and the variable resistance circuit 300 of the cartridge are high-voltage circuits that operate at a higher voltage (in this embodiment, a rating of 42 V) than the storage device 203.

  FIG. 5 is a diagram illustrating an internal configuration of the storage device 203 and the variable resistance circuit 300 in the cartridge 100. The storage device 203 includes a control unit 330 and a memory block 340. The memory block 340 includes a memory cell array that stores various data (information) including a cartridge ID indicating the type of cartridge. As will be described later, the cartridge ID is used to select the resistance value of the variable resistance circuit 300. The controller 330 controls writing and reading of data in the memory block 340 in accordance with various signals RST, SCK, VDD, SDA, and VSS supplied from the carriage circuit 500 (FIG. 4).

  The variable resistance circuit 300 includes a level shifter 310, a plurality of analog switches 321 to 324, and a plurality of resistance elements 331 to 334. Here, the resistance values of the four resistance elements 331 to 334 are set to different values (specifically, 2R, 4R, 8R, and 16R). The analog switch 321 and the resistance element 331 are connected in series between the two terminals 250 and 290. The same applies to the other analog switches 322 to 324 and the resistance elements 332 to 334. That is, between the two terminals 250 and 290, four series connections of analog switches and resistance elements are connected in parallel to each other. A high voltage VHV (= 42 V) is supplied to the level shifter 310 and the four analog switches 321 to 324 via a terminal 250. The level shifter 310 raises the voltage level of the selection signal SEL supplied from the control unit 330 of the storage device 203 from the logic level (= VDD = 3.3V) to the high voltage level (= VHV) to increase the voltage selection signal HSEL. Is supplied to the control terminals of the analog switches 321 to 324. The reason why the voltage level of the selection signal SEL is raised is that the input / output of the analog switches 321 to 324 is high voltage VHV, so that it is raised to a voltage level suitable for the control signal.

  The selection signals SEL and HSEL are signals generated by the control unit 330 based on the cartridge ID read from the memory block 340, and selectively turn on one of the plurality of analog switches 321 to 324. This is a signal for turning off another analog switch. As a result, only one of the plurality of resistance elements 331 to 334 is connected to the terminals 250 and 290 according to the selection signals SEL and HSEL. As described above, the variable resistance circuit 300 is a circuit that selectively realizes one of a plurality of resistance values in accordance with an ID stored in advance in the storage device 203. The resistance values realized by the variable resistance circuit 300 are set to different values depending on the type of cartridge. If such a variable resistance circuit 300 is provided, it is not necessary to provide a different resistance element depending on the type of cartridge, so that the design and manufacture of a plurality of cartridge circuits can be made common.

  The information stored in the storage device 203 for selecting the resistance value is not limited to the cartridge ID, but other types of selection information can be used. Further, as the internal configuration of the variable resistance circuit 300, various configurations other than those shown in FIG. 5 can be employed. The variable resistance circuit 300 shown in FIG. 5 does not use a so-called variable resistor (that can change the resistance value of one resistor), but may be configured as a circuit using a variable resistor. Good. A circuit that selects one of a plurality of resistance values without using a variable resistor as shown in FIG. 5 can also be referred to as a “resistance selection circuit”.

  In the example of FIG. 5, the variable resistance circuit 300 is provided separately from the storage device 203, but the variable resistance circuit 300 may be provided in the same semiconductor integrated circuit as the storage device 203. In this case, the power supply voltage VDD for the logic circuit and the power supply voltage VHV higher than that are supplied to the semiconductor integrated circuit, but the high voltage VHV is applied to the storage device 203 in the semiconductor integrated circuit. Instead, the high voltage VHV is applied to the variable resistance circuit 300 as a high voltage circuit.

  FIGS. 6A and 6B are explanatory views showing the contents of cartridge mounting detection processing performed by the mounting detection circuit. The mounting detection circuit 600 includes a high voltage power supply VHV for mounting detection, an individual mounting current value detection unit 630, and a determination unit 660. The individual mounting current value detection unit 630 is also simply referred to as a “mounting current value detection unit”.

１つ以上のカートリッジが未装着であれば、これに応じて合成抵抗値Ｒｃが上昇し、検出電流Ｉ_DETは低下する。 FIG. 6A shows a state where all of the cartridges IC1 to IC4 that can be mounted on the holder 4 of the printing apparatus are mounted. The resistance values of the variable resistance circuits 300 of the four cartridges IC1 to IC4 are set to different values. Specifically, among these variable resistance circuits 300, the resistance value of the variable resistance circuit 300 associated with the nth (n = 1 to 4) cartridge ICn is 2 ⁿ R (R is a constant value). Is set. The 2 ⁿ R resistors for the nth (n = 1 to N) cartridge are connected in parallel to the individual mounting current value detection unit 630. Hereinafter, the resistance realized by the variable resistance circuit 300 is also referred to as “mounting detection resistance” or simply “resistance”. The detection current _IDET detected by the individual mounting current value detection unit 630 is a value VHV / Rc obtained by dividing the voltage VHV by the combined resistance value Rc of these four mounting detection resistors. Here, when the number of cartridges is N, when all N cartridges are mounted, the detection current I _DET is given by the following equation.

If one or more cartridges are not mounted, the combined resistance value Rc increases accordingly, and the detection current _IDET decreases.

FIG. 6 (B) shows a mounting state of the cartridge IC1～IC4, the relationship between the detected current I _DET. The horizontal axis in the figure shows 16 types of mounting states, and the vertical axis shows the value of the detection current _IDET in these mounting states. The 16 types of mounting states correspond to 16 combinations obtained by arbitrarily selecting 1 to 4 cartridges from the four cartridges IC1 to IC4. These individual combinations are also referred to as “subsets”. The detection current _IDET has a current value that can uniquely identify these 16 types of mounting states. In other words, the individual resistance values of the four variable resistance circuits 300 in the four cartridges IC1 to IC4 are set so that the 16 types of mounting states that the four cartridges can take give different combined resistance values Rc. Yes.

If the four cartridges IC1~IC4 all mounted state, the detection current I _DET is at its maximum value Imax. On the other hand, when only the cartridge IC4 having the variable resistance circuit 300 having the largest resistance value 16R is not attached, the detection current I _DET is 0.93 times the maximum value Imax. Therefore, if it is checked whether or not the detection current I _DET is equal to or greater than the threshold current Ithmax set in advance as a value between these two current values, whether all four cartridges IC1 to IC4 are mounted. It is possible to detect whether or not. Incidentally, for individual mounting detection, reason for using the high voltage VHV than the power supply voltage of the normal logic circuit (approximately 3.3V), by a wider dynamic range of the detected current I _DET, improve the detection accuracy Because.

Individual mounting current value detection unit 630 converts the detected current I _DET into a digital detection signal S _IDET, transmits the digital detection signal S _IDET to the determination unit 660. The determination unit 660 can determine which of the 16 types of mounting states from the value of the digital detection signal S _IDET . When it is determined that one or more cartridges are not mounted, the determination unit 660 displays information (characters or images) indicating the unmounted state on the display panel 30 to notify the user.

  In the first embodiment, since the unmounted state of each cartridge is displayed on the display panel 30 during cartridge replacement, the user can perform cartridge replacement while viewing this display. In particular, when the cartridge is replaced, the display panel 30 displays that the cartridge has been changed from being not mounted to being mounted. Therefore, even a user unfamiliar with the cartridge replacement work can proceed to the next operation with peace of mind. . In the first embodiment, since the cartridge can be attached and detached and the attachment can be detected while the cartridge storage device 203 is de-energized, it is possible to prevent the occurrence of bit errors caused by so-called hot-swapping of the storage device. Is possible.

B. Tolerance of resistance element for cartridge attachment detection:
As described with reference to FIGS. 6A and 6B, in the cartridge mounting detection process, the combined resistance value Rc is uniquely determined according to 2 ^N types of mounting states related to the ^N cartridges, and is detected accordingly. The fact that the current _IDET is uniquely determined is used. Hereinafter, an allowable error of the resistance value realized by the variable resistance circuit 300 will be considered.

First, consider the case where the number N of cartridges is four. When the tolerance of the resistance value is ε, the resistance values of the variable resistance circuits 300 (FIG. 6A) are (1 ± ε) 2R, (1 ± ε) 4R, (1 ± ε) 8R, It is allowed to take a value in the range of (1 ± ε) 16R. By the way, of the 16 types of mounting states in FIG. 6B, the two states with the smallest difference in the combined resistance value Rc and the largest detection current I _det are the states in which all the cartridges IC1 to IC4 are mounted. Only the fourth cartridge IC4 is not attached. Here, let R _c1 be the first combined resistance value when all the cartridges IC1 to IC4 are mounted, and let R _c2 be the second combined resistance value when only the fourth cartridge IC4 is not mounted. R _c1 <R _c2 holds. This relationship is preferably established also when the resistance value realized by each variable resistance circuit 300 fluctuates within the allowable error ε. At this time, the worst condition is a case where the first combined resistance value R _c1 takes the maximum value R _c1max and the second combined resistance value R _c2 takes the minimum value R _c2min . At this time, it is preferable that R _c1max <R _c2min is satisfied, and when this is rewritten, the following equation is obtained.

R _c1max and R _{c2min in the} equation (3) are given by the following equations, respectively.

Substituting Equations (4) and (5) into Equation (3) establishes the following Equation (6), and transforming this to Equation (7).

In the equation (7), the error ε is sufficiently smaller than 1, so if (1−ε) = 1, the following equation is established, and the allowable error ε of the resistance value is 3.6%.

To generalize the above consideration, when the number of cartridges is N, the allowable error ε is given by the following equation.

That is, if the allowable error ε satisfies the expression (9), it is guaranteed that the combined resistance value Rc is always uniquely determined according to the mounted state of the N cartridges, and the detection current _IDET is uniquely determined according to this. can do. However, it is preferable to set the tolerance of the actual resistance value in design to a value smaller than the value on the right side of the equation (9). Further, the tolerance of the resistance value realized by each variable resistance circuit 300 may be set to a sufficiently small value (for example, a value of 1% or less) without performing the above-described examination.

C. Second embodiment:
FIG. 7 is a block diagram illustrating an electrical configuration of the ink cartridge 100 and the printing apparatus 1000 according to the second embodiment. The main control circuit 40 includes a CPU 410, a memory 420, and a non-wearing state detection unit 430. The memory 420 stores a threshold value table TT that stores threshold values used when determining whether or not a cartridge is mounted. The CPU 410 determines the type of cartridge mounted in the holder 4 using the threshold value read from the threshold value table TT (described later). The threshold value table TT is preferably stored in a nonvolatile memory such as an EEPROM. The carriage circuit 500 includes a memory control circuit 501 and a cartridge detection circuit 502.

  The cartridge detection circuit 502 is a circuit for detecting mounting of a cartridge in the holder 4 in cooperation with the main control circuit 40. In the second embodiment, the cartridge detection circuit 502 and the main control circuit 40 cooperate to execute a mounting detection process similar to that of the mounting detection circuit 600 (FIG. 6A) of the first embodiment. Therefore, these circuits 502 and 40 can also be called “mounting detection circuits”. The cartridge detection circuit 502 and the variable resistance circuit 300 of the cartridge are high voltage circuits that operate at a higher voltage (in this embodiment, a rating of 42 V) than the storage device 203.

  FIG. 8 is a diagram illustrating an internal configuration of the cartridge detection circuit 502 according to the second embodiment. Here, a state in which four cartridges 100 are mounted on the holder is shown, and reference numerals IC1 to IC4 are used to distinguish the cartridges. The cartridge detection circuit 502 includes a detection voltage control unit 610, an overvoltage detection unit 620, and an individual mounting current value detection unit 630.

In the cartridge detection circuit 502, a high voltage power supply VHV for detecting attachment is provided. This high voltage power supply VHV is connected in parallel to four device-side terminals 550 provided at the mounting positions of the cartridges IC1 to IC4 via the transistor 612. The voltage value of the high voltage power supply VHV is referred to as “high voltage VHV”. The transistor 612 is on / off controlled by the detection voltage control unit 610. Each device-side terminal 550 is connected to the first mounting detection terminal 250 of the corresponding cartridge. In each cartridge, a variable resistance circuit 300 is provided between the first and second mounting detection terminals 250 and 290, respectively. The resistance values of the variable resistance circuits 300 of the four cartridges IC1 to IC4 are set to different values. Specifically, the resistance value of the variable resistance circuit 300 associated with the nth (n = 1 to 4) cartridge ICn is set to 2 ⁿ R (R is a constant value). Note that the resistance values of these variable resistance circuits 300 are the same as those shown in FIG. The 2 ⁿ R resistors for the nth (n = 1 to N) cartridge are connected in parallel between the power supply VHV and the individual mounting current value detection unit 630. The individual mounting current value detection unit 620 detects a detection current _IDET determined according to the mounting state of these cartridges. The detection current I _DET is also referred to as “mounting detection current”. This detection current _IDET is given by the equations (1) and (2) described in the first embodiment.

  Within each cartridge, the first and second overvoltage detection terminals 210 and 240 are connected by wiring. The first overvoltage detection terminal 210 of the first cartridge IC1 is connected to a wiring 651 in the cartridge detection circuit 502 via a corresponding device-side terminal 510, and this wiring 651 is connected to a low voltage via a resistor 652. Connected to the power supply VDD. The wiring 651 is connected to the non-wearing state detection unit 430 (FIG. 7) in the main control circuit 40. The voltage value of the low voltage power supply VDD is referred to as “low voltage VDD”. The second overvoltage detection terminal 240 of the nth (n = 1 to 3) cartridge and the first overvoltage detection terminal 210 of the (n + 1) th cartridge are connected to each other via corresponding device side terminals 540 and 510. The The second overvoltage detection terminal 240 of the fourth cartridge IC 4 is connected to the ground potential via the resistor 654. If all the cartridges IC1 to IC4 are mounted in the holder, the voltage of the wiring 651 connected to the non-mounted state detection unit 430 is a predetermined voltage obtained by dividing the power supply voltage VDD by the two resistors 652 and 654. Value. On the other hand, if there is at least one unmounted cartridge, the voltage of the wiring 651 becomes the power supply voltage VDD. Therefore, the non-mounted state detection unit 430 can determine whether or not there is an unmounted cartridge by monitoring the voltage of the wiring 651. As described above, in the second embodiment, when all the cartridges IC1 to IC4 are mounted in the holder, the overvoltage detection terminals 240 and 210 of each cartridge are sequentially connected in series. It is possible to immediately determine whether or not one or more cartridges are not mounted.

  Further, the first overvoltage detection terminals 210 of the four cartridges IC1 to IC4 are connected to the anode terminals of the diodes 641 to 644 via the corresponding device side terminals 510. The second overvoltage detection terminals 240 of the four cartridges IC1 to IC4 are connected to the anode terminals of the diodes 642 to 645 via the corresponding device side terminals 540. The anode terminal of the second diode 642 is commonly connected to the second overvoltage detection terminal 240 of the first cartridge IC1 and the first overvoltage terminal 210 of the second cartridge IC2. Similarly, the diodes 643 and 644 are connected in common to the second overvoltage detection terminal 240 of one cartridge and the first overvoltage detection terminal 210 of the adjacent cartridge. The cathode terminals of these diodes 641 to 645 are connected in parallel to the overvoltage detection unit 620. These diodes 641 to 645 are used to monitor whether or not an abnormal high voltage (specifically, a voltage exceeding the voltage value of the low voltage power supply VDD) is not applied to the overvoltage detection terminals 210 and 240. Is done. Such an abnormal voltage value (referred to as “overvoltage”) is generated when an unintended short circuit occurs between one of the overvoltage detection terminals 210 and 240 of each cartridge and one of the attachment detection terminals 250 and 290. appear. For example, when ink droplets or dust adhere to the surface of the substrate 200 (FIG. 3A), the first overvoltage detection terminal 210 and the first mounting detection terminal 250 or the second overvoltage detection terminal 240 and There is a possibility that an unintended short circuit may occur between the second attachment detection terminals 290. When such an unintentional short circuit occurs, a current flows to the overvoltage detection unit 620 via any of the diodes 641 to 645. Therefore, the overvoltage detection unit 620 determines whether or not an overvoltage has occurred and whether an unintended short circuit has occurred. The presence or absence can be determined. When an overvoltage is detected, a signal indicating the occurrence of an overvoltage is supplied from the overvoltage detection unit 620 to the detection voltage control unit 610, and the detection voltage control unit 610 turns off the transistor 612 in response to this. This is to prevent damage to the printing apparatus and cartridge that may occur due to overvoltage. The overvoltage detection unit 620 can also be called a short circuit detection unit.

  As described above, in the second embodiment, the overvoltage detection terminals 210 and 240 are configured to detect whether all the cartridges are mounted in the holder 4 (all cartridge mounting detection), and the overvoltage detection terminals 210 and 240. It is used for both the detection processing for the presence or absence of an unintended short circuit between the mounting detection terminals 250 and 290. However, one or both of these two detection processes can be omitted. When neither of these two detection processes using the overvoltage detection terminals 210 and 240 is performed, circuit elements such as the overvoltage detection terminals 210, 240, 510, and 540, the diodes 641 to 645, the overvoltage detection unit 620, and the like. Can be omitted.

  FIG. 9 is a flowchart showing the entire procedure of the mounting detection process performed by the main control circuit 40 and the cartridge detection circuit 502. This mounting detection process is started when the carriage 3 stops at a position for cartridge replacement (referred to as “cartridge replacement position”) and the cover 11 (FIG. 1) of the holder 4 is opened. The cartridge replacement position is preset in the vicinity of one end of the carriage 3 in the main scanning direction (for example, near the right end in FIG. 1). At the cartridge replacement position, the cartridge storage device 203 is in a non-energized state (a state where the power supply voltage VDD is not supplied).

  When the carriage 3 stops at the cartridge replacement position, the non-mounting state detection unit 430 (FIG. 7) detects whether or not all the cartridges are mounted in the holder 4 in steps S110 and S120. If all the cartridges are mounted, the process proceeds from step S120 to step S140 described later. On the other hand, if one or more cartridges are not mounted, the main control circuit 40 executes non-mounting error processing in step S130. The non-mounting error process is a process for displaying, for example, a notification such as “The cartridge is not correctly mounted” (notification that there is an unmounted cartridge) on the display panel 30. In step S140, the detection voltage control unit 610 (FIG. 8) of the cartridge detection circuit 502 switches the transistor 612 from off to on, and the high voltage VHV for mounting detection is used as a cartridge mounting detection device (a variable resistance in this embodiment). Circuit 300). In steps S150 and S160, the overvoltage detection unit 620 detects whether or not an overvoltage (a voltage higher than the power supply voltage VDD) is generated. If an overvoltage has occurred, in step S200, the overvoltage detection unit 620 notifies the detection voltage control unit 610 that the overvoltage has occurred, and turns off the transistor 612. In this case, an indication may be displayed on the display panel 30 that an overvoltage has occurred, or that an operation for removing and inserting the cartridge once and inserting it again is performed. On the other hand, if no overvoltage has occurred, the process proceeds from step S160 to step S170, and the individual mounting detection process of the cartridge is executed.

FIG. 10 is a flowchart showing a detailed procedure of the individual mounting detection process. In step S210 (1), the CPU 410 _compares the value of the digital detection signal S _IDET supplied from the individual mounting detection unit 630 with the first threshold value. The first threshold is when the cartridge IC4 associated with the detected resistance value I _DET when all the cartridges are not mounted and the variable resistance circuit 300 functioning as the resistor with the largest resistance value is mounted. This is a preset value corresponding to the current value between the detected current value I _DET and the detected current value I _DET . If the detected current value I _DET is equal to or smaller than the first threshold value, all the cartridges are not mounted. Therefore, in step S220, that effect is displayed on the display panel 30 and the process is terminated. In the same manner, until the step S210 (2 ^N −1), 2 ^N pieces shown in the lower part of FIG. 6B are compared by comparing the preset threshold value with the detected current value I _DET . It is possible to determine the state (mounting pattern) and display the determination result (type of unmounted cartridge) on the display panel 30. In this embodiment, since N = 4, 15 threshold values are used. However, any integer greater than or equal to 2 can be adopted as N, and typically 3, 4, or 6 is adopted as N.

  When the individual mounting detection process is thus completed, the process returns to step S180 in FIG. 9 to determine whether or not the cover 11 of the holder 4 is closed. If the cover 11 is not closed, the process returns from step S180 to step S110, and the processes after step S110 are executed again. On the other hand, when the cover 11 is closed, in step S190, the detection voltage control unit 610 turns off the transistor 612 for mounting detection, and the process is completed.

  As described above, in the second embodiment, the unmounted state of each cartridge is displayed on the display panel 30 during the cartridge replacement. Therefore, the user can execute the cartridge replacement while viewing this display. is there. In particular, when a new cartridge is mounted in the holder 4 when replacing the cartridge, the fact that the cartridge is mounted is displayed on the display panel 30, so even a user who is unfamiliar with the cartridge replacement operation can proceed to the next operation with peace of mind. Is possible. Further, in the second embodiment, since cartridge insertion / removal and attachment detection can be performed in a state where the cartridge storage device 203 is not energized, it is possible to prevent the occurrence of bit errors caused by so-called hot-swapping of the storage device. Is possible.

  In the second embodiment, when an overvoltage is generated at the overvoltage detection terminals 250 and 290, the application of the high voltage VHV for detection of mounting is immediately canceled, so that the electrical circuit of the printing apparatus or cartridge is caused by the overvoltage. It is possible to prevent damage from occurring.

D. Modified example of the wearing detection circuit:
FIG. 11 is a circuit diagram illustrating another configuration example of the mounting detection circuit. This circuit is different from the circuit in FIG. 6A in the resistance values of the resistance elements 633 and 634. In the circuit of FIG. 11, the resistance values of the variable resistance circuit 300 in the four cartridges IC1 to IC4 are 2R, 4R, 10R, and 30R. Here, the ratio values of the resistance values associated with the two cartridges are 2, 2.5, and 3, which are different values. In general, if a value of 2 or more is adopted as the ratio of the resistance values of the resistors associated with the two cartridges, the combined resistance value Rc is uniquely determined according to the 2 ^N types of mounting states of the ^N cartridges. A circuit configuration that is determined can be obtained. As can be understood from this example, the resistance value of the variable resistance circuit 300 in each cartridge does not have to be 2 ⁿ R, and the combined resistance value Rc is uniquely determined according to 2 ^N types of mounting states of ^N cartridges. Various resistance values that can be determined can be adopted.

FIG. 12 is a circuit diagram showing still another configuration example of the mounting detection circuit. In this circuit, resistance elements 631 to 634 directly connected to the variable resistance circuit 300 of the cartridge in FIG. These resistance elements 631 to 634 can be provided, for example, in the cartridge detection circuit 502 (FIG. 8). The resistance values of the variable resistance circuit 300 of each cartridge are set to R, 2R, 4R, and 8R, and the resistance values of the resistance elements 631 to 634 are also set to R, 2R, 4R, and 8R. As a result, resistors 701 to 704 (resistance values 701 to 704 (n = 1 to N)) having resistance values of 2 ⁿ R (n = 1 to N) are connected in series with the variable resistance circuit 300 in the nth cartridge and the resistance element 63n in the cartridge detection circuit 502. (Referred to as “series connection resistance”). Even in this configuration, the determination unit 660 (FIG. 6) or the CPU 410 (FIG. 7) can determine that the cartridge is mounted.

As the electrical device connected to the cartridge mounting detection terminals 250 and 290 (FIG. 3A), any type of electrical device other than the variable resistance circuit 300 can be employed. However, such an electrical device, when the N cartridge is mounted, all in the holder 4, so that the detected current I _DET for individual mounting detection, the preset threshold current Ithmax more It is preferable to be configured.

  The various modifications and changes related to the first and second embodiments described above can also be applied to other embodiments described below.

E. Third embodiment:
In the third embodiment, the overall configuration of the circuit is the same as that of the second embodiment shown in FIG. 8, and the internal configuration of the cartridge detection circuit is different from that of the second embodiment.

  FIG. 13 is a circuit diagram showing a configuration of a cartridge detection circuit in the third embodiment. 8 differs from the circuit shown in FIG. 8 in that the resistors 652 and 654 depicted in the cartridge detection circuit shown in FIG. 8 are omitted, the detection pulse generator 650 is provided, and the voltage at the output terminal of the transistor 612. The value VHO is supplied to the individual mounting current value detection unit 630a, and other configurations are the same as those in FIG. The detection pulse generator 650 generates a rectangular detection pulse DP in step S110 of FIG. The detection pulse DP is received by the non-attached state detection unit 430 (FIG. 8) after sequentially passing through the overvoltage detection terminals 240 and 210 of all the ink cartridges. The non-attached state detection unit 430 analyzes the waveform of the detection pulse DP to determine whether the contact state of the ink cartridge terminal is an insufficient contact state (contact failure) with high resistance. It is possible. That is, the non-mounting state detection unit 430 can detect not only whether all the cartridges are mounted but also whether the cartridge is in an insufficient contact state. If the contact state is insufficient, for example, a notification that prompts the user to remount the cartridge may be displayed on the display panel 30.

  FIG. 14 is a diagram illustrating an internal configuration of the individual mounting current value detection unit 630a according to the third embodiment. The individual mounting current value detection unit 630a includes a current-voltage conversion unit 710, a voltage comparison unit 720, a comparison result storage unit 730, and a voltage correction unit 740.

ここで、ＶＨＯはトランジスタ５１２（図１３）の出力電圧、Ｒｃは４つの可変抵抗回路３００（図６（Ａ））の合成抵抗である。この出力電圧Ｖ_DETは、検出電流Ｉ_DETを表す電圧値を有する。 The current-voltage conversion unit 710 is an inverting amplifier circuit including an operational amplifier 712 and a feedback resistor R11. The output voltage V _DET of the operational amplifier 712 is given by the following equation.

Here, VHO is an output voltage of the transistor 512 (FIG. 13), and Rc is a combined resistance of the four variable resistance circuits 300 (FIG. 6A). This output voltage V _DET has a voltage value representing the detection current I _DET .

The voltage V _DET given by the equation (10) indicates a value obtained by inverting the voltage I _DET · R11 based on the detection current I _DET . Therefore, an inverting amplifier may be added to the current-voltage conversion unit 710, and a voltage obtained by inverting the voltage V _DET with this additional inverting amplifier may be output as the output voltage of the current-voltage conversion unit 710. The absolute value of the amplification factor of this additional inverting amplifier is preferably 1.

The voltage comparison unit 720 includes a threshold voltage generation unit 722, a comparator 724 (an operational amplifier), and a switching control unit 726. The threshold voltage generation unit 722 selects and outputs one of a plurality of threshold voltages Vth (j) obtained by dividing the reference voltage Vref by a plurality of resistors R1 to Rm with the changeover switch 723. The plurality of threshold voltages Vth (j) correspond to threshold values for identifying the values of the detection current _IDET in the 16 types of wearing states shown in FIG. The comparator 724 compares the output voltage V _DET of the current-voltage converter 710 with the threshold voltage Vth (j) output from the threshold voltage generator 722 and outputs a binary comparison result. To do. This binary comparison result indicates whether or not the individual cartridges IC1 to IC4 are mounted. That is, the voltage comparison unit 720 checks whether or not the individual cartridges IC1 to IC4 are mounted, and sequentially outputs the comparison results. In a typical example, the voltage comparison unit 720 first checks whether or not the first cartridge IC1 associated with the variable resistance circuit 300 (FIG. 6A) having the largest resistance value is mounted. The bit value indicating the comparison result is output. Thereafter, it is sequentially checked whether or not the second to fourth cartridges IC2 to IC4 are mounted, and a bit value indicating the comparison result is output. The switching control unit 726 performs control to switch the voltage value Vth (j) to be output from the threshold voltage generation unit 722 for detection of the next cartridge mounting based on the comparison result for each cartridge.

The comparison result storage unit 730 switches the binary comparison result output from the voltage comparison unit 720 with the changeover switch 732 and stores it in an appropriate bit position in the bit register 734. The switching timing of the selector switch 732 is designated by the switching control unit 726. The bit register 734 includes N cartridge detection bits (N = 4 in this case) that indicate whether or not individual cartridges that can be mounted on the printing apparatus are mounted, and an abnormal flag bit that indicates that an abnormal current value is detected. have. The abnormality flag bit becomes H level when a current that is significantly larger than the current value Imax (FIG. 6B) in a state where all cartridges are mounted flows. However, the abnormality flag bit can be omitted. The plurality of bit values stored in the bit register 734 are transmitted to the CPU 410 (FIG. 8) of the main control circuit 40 as a digital detection signal S _IDET (detection current signal). The CPU 410 determines whether or not each cartridge is mounted from the bit value of the digital detection signal S _IDET . As described above, in the third embodiment, the four bit values of the digital detection signal S _IDET indicate whether or not each cartridge is mounted. Therefore, the CPU 410 does not need to execute the process of step S210 shown in FIG. 10, and can immediately determine whether or not each cartridge is mounted from each bit value of the digital detection signal S _IDET. It is.

  Both the voltage comparison unit 720 and the comparison result storage unit 730 constitute a so-called AD conversion unit. As the A-D conversion unit, various other known configurations can be employed instead of the voltage comparison unit 720 and the comparison result storage unit 730 illustrated in FIG. 14.

The voltage correction unit 740 corrects the plurality of threshold voltages Vth (j) generated by the threshold voltage generation unit 722 following the fluctuation of the high voltage VHV (FIG. 13) for mounting detection. Circuit. The voltage correction unit 740 is configured as an inverting amplifier circuit including an operational amplifier 742 and two resistors R21 and R22. The output terminal voltage VHO of the transistor 612 in FIG. 13 is input to the inverting input terminal of the operational amplifier 742 via the input resistor R22, and the reference voltage Vref is input to the non-inverting input terminal. At this time, the output voltage AGND of the operational amplifier 742 is given by the following equation.

The voltage AGND is used as a reference voltage AGND on the low voltage side of the threshold voltage generator 722. For example, if Vref = 2.4V, VHO = 42V, R21 = 20 kΩ, and R22 = 400 kΩ, AGND = 0.42V. As can be understood by comparing Equation (10) and Equation (11) described above, the reference voltage AGND on the low voltage side of the threshold voltage generation unit 722 is similar to the detection voltage value V _DET , as in the transistor 612. Of the output voltage VHO (that is, the high voltage power supply VHV for mounting detection). The difference between these two voltages AGND and V _DET is caused by the difference between the resistance ratios R21 / R22 and R11 / Rc. If such a voltage correction unit 740 is used, a plurality of threshold voltages Vth (j) generated by the threshold voltage generation unit 722 can be obtained even if the power supply voltage VHV for mounting detection varies for some reason. , And changes following the fluctuation of the power supply voltage VHV. As a result, since both the detection voltage value V _DET and the plurality of threshold voltages Vth (j) change following the fluctuation of the power supply voltage VHV, the voltage comparison unit 720 shows a comparison result representing an accurate mounting state. Obtainable. In particular, if the resistance ratio R21 / R22 and the resistance ratio R11 / R _c1 (R _c1 is the combined resistance value when all cartridges are mounted) are set equal, the detection voltage value V _DET and the plurality of threshold voltages Vth (j ) Can be accurately followed so as to change with substantially the same change width with respect to the fluctuation of the power supply voltage VHV. However, the voltage correction unit 720 may be omitted.

Thus, the third embodiment can also achieve the same effects as those of the second embodiment described above. That is, since the unmounted state of each cartridge is displayed on the display panel 30 during the replacement of the cartridge, the user can execute the cartridge replacement while viewing this display. In addition, since the cartridge can be removed and mounted while the cartridge storage device 203 is not energized, it is possible to prevent bit errors caused by hot-plugging of the storage device. Further, when an overvoltage is generated at the overvoltage detection terminals 250 and 290, the application of the high voltage VHV for mounting detection is immediately canceled, so that the electrical circuit of the printing apparatus or cartridge is prevented from being damaged by the overvoltage. Is possible. In the third embodiment, each bit value of the digital detection signal S _IDET generated by the individual mounting current value detection unit _630a indicates whether or not each cartridge is mounted. Therefore, whether or not each cartridge is mounted _Can be immediately determined from the bit value of the digital detection signal S _IDET .

F. Fourth embodiment:
FIG. 15 is a diagram illustrating a configuration of the individual mounting detection unit 630b according to the fourth embodiment. This individual mounting detection unit 630b is obtained by adding an input changeover switch 750 to the individual mounting detection unit 630a of the third embodiment shown in FIG. The input changeover switch 750 is for selecting any one of the detection currents I _{DET1 to} I _DET4 input from the plurality of input terminals 751 to 754 and inputting the selected current to the current-voltage conversion unit 710. The detection current I _DET1 flowing through the parallel connection of the same variable resistance circuit 300 as shown in FIG. _6A is input to the first input terminal 751. Similarly, detection currents I _{DET2 to} I _DET4 flowing through parallel connections of resistors corresponding to four or less cartridges are also input to the other input terminals 752 to 754, respectively. The other circuit elements 710 to 740 are the same as those in FIG. 14, and therefore their internal configurations are not shown in FIG. 15.

  If such an input changeover switch 750 is provided, it is possible to detect mounting of individual cartridges in a printing apparatus in which a large number of cartridges are mounted, as described above.

G. Other embodiments:
FIG. 16 is a diagram showing a configuration of a substrate in another embodiment. These substrates 200a to 200c differ only in the surface shapes of the substrate 200 and the terminals 210 to 290 shown in FIG. However, also in these board | substrates 200a-200c, arrangement | positioning of the contact part cp with the apparatus side terminal corresponding to each terminal 210-290 is the same as the board | substrate 200 of FIG. 3 (A). As described above, the surface shape of each terminal can be variously modified as long as the arrangement of the contact portions cp is the same.

  17 and 18 are perspective views showing the configuration of an ink cartridge according to another embodiment. This ink cartridge is separated into an ink container 100B and an adapter 100A.

  The ink storage unit 100B includes a casing 101B that stores ink and an ink supply port 110. An ink chamber 120B for storing ink is formed inside the housing 101B. The ink supply port 110 is formed on the bottom wall of the housing 101B. The ink supply port 110 communicates with the ink chamber 120B.

  The adapter 100A includes a main body 101A and a substrate 200. Inside the main body 101A, a space 101AS for receiving the ink containing portion 100B is formed. An opening leading to the space 101AS is provided in the upper part of the main body 101A. In a state where the ink storage unit 100B is stored in the space 101AS, the ink supply port 110 protrudes outside the adapter 100A through the opening 101AH. A part of the side wall of the adapter 100A can be omitted.

  In this manner, the ink cartridge can be separated into the ink storage portion 100B (also referred to as “printing material storage body”) and the adapter 100A. In this case, the circuit board 200 is preferably provided on the adapter 100A side.

H. Variations:
The present invention is not limited to the above-described embodiments and embodiments, and can be implemented in various modes without departing from the gist thereof. For example, the following modifications are possible.

・ Modification 1:
In each of the above embodiments, the storage device 203 and the variable resistance circuit 300 are mounted on the ink cartridge. However, the plurality of electrical devices mounted on the ink cartridge is not limited to these, and one or more arbitrary Different types of electrical devices may be mounted on the ink cartridge. For example, as a sensor for detecting the ink amount, an electric device (for example, a piezoelectric element or a resistance element) may be provided in the ink cartridge instead of the optical sensor. Moreover, in the said embodiment, although both the memory | storage device 203 and the variable resistance circuit 300 are provided in the board | substrate 200, the electrical device of a cartridge can be arrange | positioned on other arbitrary members. For example, the storage device 203 may be disposed on a cartridge housing, an adapter, or another structure separate from the cartridge.

Modification 2
In each of the above embodiments, four mounting detection resistors are formed in the variable resistance circuit 300 in the nth cartridge. The resistance values of these mounting detection resistors are the same as those of the variable resistance circuit 300 and other resistance elements. You may implement | achieve by the parallel connection or serial connection with. When one mounting detection resistor is constituted by a plurality of resistance elements, the distribution of resistance values of these resistance elements can be arbitrarily changed. Further, these single resistance element or a plurality of resistance elements may be provided only in one of the cartridge and the printing apparatus main body. For example, if all the mounting detection resistors are provided on the cartridge, the printing device main body does not require a resistance element constituting the mounting detection resistor.

・ Modification 3:
Of the various constituent elements described in the above embodiments, constituent elements that are not related to a specific purpose / action / effect can be omitted.

・ Modification 4:
In each of the above embodiments, the present invention is applied to the ink cartridge. However, the present invention is not limited to the ink cartridge, and the present invention can be similarly applied to other printing materials, for example, a printing material container containing toner. is there.

DESCRIPTION OF SYMBOLS 2 ... Carriage motor 3 ... Carriage 4 ... Holder 5 ... Print head 6 ... Ink supply needle 10 ... Paper feed roller 11 ... Cover 30 ... Display panel 37 ... Flexible cable 40 ... Main control circuit 100 ... Ink cartridge (printing material cartridge)
DESCRIPTION OF SYMBOLS 100A ... Adapter 100B ... Ink storage part 101 ... Case 101A ... Main body 101AH ... Opening 101AS ... Space 101B ... Case 102 ... Cover body 110 ... Ink supply port 120, 120B ... Ink chamber 200 ... Substrate (circuit board)
201 ... boss groove 202 ... boss hole 203 ... storage device 204 ... resistance element 206 ... constant voltage source 210,240 ... overvoltage detection terminal 220 ... reset terminal 230 ... clock terminal 250,290 ... mounting detection terminal 260 ... power supply terminal 270 ... grounding Terminal 280 ... Data terminal 300 ... Variable resistance circuit 310 ... Level shifter 321-324 ... Analog switch 331-334 ... Resistance element 410 ... CPU
420 ... Memory 430 ... Non-mounting state detection unit 500 ... Carriage circuit 501 ... Memory control circuit 502 ... Cartridge detection circuit 510-590 ... Device side terminal 600 ... Mounting detection circuit 610 ... Detection voltage control unit 612 ... Transistor 620 ... Overvoltage detection unit 630 ... Individual mounting detection unit 631 to 634 ... Resistance element 642 to 645 ... Diode 650 ... Detection pulse generation unit 651 ... Wiring 652, 654 ... Resistance 660 ... Determination unit 701 to 704 ... Series connection resistance 710 ... Current-voltage conversion unit 712 ... Operational amplifier 720 ... Voltage comparison unit 722 ... Threshold voltage generation unit 723 ... Changeover switch 724 ... Comparator (operational amplifier)
726 ... Switching control unit 730 ... Comparison result storage unit 732 ... Changeover switch 734 ... Bit register 740 ... Voltage correction unit 742 ... Operational amplifier 750 ... Input changeover switch 751 to 754 ... Input terminal 1000 ... Printing device

Claims (6)

A printing device,
A holder on which different N (N is an integer of 2 or more) printing material cartridges that can be mounted independently from each other;
A power supply for mounting detection; and a mounting current value detection unit that detects a detection current that flows when one or more printing material cartridges are mounted in the holder, and the N printing materials according to the detected current A mounting detection circuit for detecting the mounting state of the cartridge;
With
Each of the N printing material cartridges includes a storage device for storing information about the stored printing material, an electrical device for mounting detection, a terminal for the storage device, and a terminal for the electrical device. And
The electrical device of the N printing material cartridges selectively takes one of a plurality of resistance values in accordance with selection information stored in advance in the storage device, whereby the N printing materials. It has a variable resistance circuit that realizes different resistance values in the cartridge,
The variable resistance circuits of the N printing material cartridges are:
(I) Connected in parallel between the mounting detection power source and the mounting current value detection unit,
(Ii) When all the N printing material cartridges are mounted in the holder, the detected current detected by the mounting current value detection unit indicates 2 ^N types of mounting states related to the ^N printing material cartridges. A printing device configured to take a uniquely identifiable current value. The printing apparatus according to claim 1,
The variable resistance circuit of the nth (n = 1 to N) printing material cartridge among the N printing material cartridges is connected in parallel between the mounting detection power source and the mounting current value detection unit. A resistance for mounting detection is formed alone or in series connection with other resistance elements provided in the mounting detection circuit,
The mounting detection resistance for the nth printing material cartridge is 2 ⁿ R (1 when R is a constant value and the tolerance ε is 1 / {4 (2 ^N−1 −1)}. A printing device configured to have a resistance value within a range of ± ε). The printing apparatus according to claim 2,
The mounting current value detection unit
A current-voltage converter that generates a detection voltage by converting the detection current into a voltage;
An AD converter for sequentially comparing the mounting detection voltage with a plurality of threshold voltages and converting the detected voltage into a digital detection signal;
A voltage correction unit that corrects the plurality of threshold voltages by following a change in voltage of the power supply for mounting detection;
With
The mounting detection circuit determines a mounting state of a printing material cartridge in the holder based on the digital detection signal. The printing apparatus according to any one of claims 1 to 3,
A voltage higher than the voltage applied to the storage device terminal is supplied from the mounting detection power source to the electrical device terminals of the N printing material cartridges,
Each of the N printing material cartridges further has an overvoltage detection terminal provided in the vicinity of the terminal for the electric device,
The mounting detection circuit stops a supply of voltage from the mounting detection power source to the electric device when an overvoltage is detected via the overvoltage detection terminal. A power supply for mounting detection; and a mounting current value detection unit that detects a detection current that flows when one or more printing material cartridges are mounted in a holder of a printing apparatus, and the printing material in the holder is in accordance with the detected current A printing material cartridge mounted in the holder of the printing apparatus including a mounting detection circuit for detecting a mounting state of the cartridge,
The printing material cartridge includes a storage device for storing information relating to the stored printing material, an electrical device for mounting detection, a terminal for the storage device, and a terminal for the electrical device. And
The electrical device includes a variable resistance circuit that selectively takes one of a plurality of resistance values according to selection information stored in advance in the storage device,
The variable resistance circuit is:
(I) Connected in parallel between the mounting detection power source and the mounting current value detection unit,
(Ii) When all N printing material cartridges (N is an integer of 2 or more) that can be mounted in the holder are mounted, the detected current detected by the mounting current value detection unit is the N printings. A printing material cartridge configured to take a current value capable of uniquely identifying 2 ^N types of mounting states related to the material cartridge. The printing material cartridge according to claim 5,
The variable resistance circuit includes a mounting detection resistor connected in parallel between the mounting detection power source and the mounting current value detection unit, either alone or with another resistance element provided in the mounting detection circuit. Formed in series,
Of the N printing material cartridges mounted in the holder, the mounting detection resistance for the nth (n = 1 to N) printing material cartridge has a constant value R and an allowable error ε of 1 /. A printing material cartridge configured to have a resistance value in a range of 2 ⁿ R (1 ± ε) when {4 (2 ^N-1 -1)}.

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