Image forming device

Abstract

To provide a technique that can reduce the possibility that defect may occur in an element substrate.SOLUTION: An image forming device comprises: an attachment part which a printing cartridge provided with a recording element and an element substrate having a plurality of terminals can be detachably attached to; a first device substrate that supplies a signal to the element substrate; a second device substrate that relays the signal supplied from the first device substrate to supply the signal to the element substrate; and a connection terminal part having a plurality of connection terminals that are connected to the plurality of terminals respectively. The second device substrate comprises a switch circuit that switches a state into either of an ON state where the signal supplied from the first device substrate is supplied to the element substrate and an OFF state where the signal is not supplied.SELECTED DRAWING: Figure 10

Description

Technical Field

[0001] The present disclosure relates to the technology of an image forming apparatus.

Background Art

[0002] Conventionally, a recording apparatus in which an ink cartridge having an element substrate is detachably mounted is known (for example, Patent Documents 1, 2, and 3). The element substrate has a plurality of terminals. The recording apparatus also has a plurality of connection terminals corresponding to the plurality of terminals.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the conventional technology, when the ink cartridge is mounted on the recording apparatus, the plurality of terminals of the element substrate and the plurality of connection terminals of the recording apparatus come into contact with each other and conduct electricity, so that the element substrate and the control device of the recording apparatus are electrically connected, and signals are exchanged between the element substrate and the control device. Further, in the conventional technology, when conduction between the terminals is not achieved due to poor contact between the plurality of terminals and the plurality of connection terminals, a problem may occur in the element substrate. For example, when a signal such as a power supply voltage is supplied from the recording apparatus to the element substrate in a state where conduction cannot be achieved due to poor contact between the ground terminal of the element substrate and the device-side ground terminal of the recording apparatus, problems such as destruction of the element substrate may occur. Such problems are common not only to recording apparatuses on which ink cartridges are mounted, but also to the technology of image forming apparatuses on which cartridges are detachably mounted.

Means for Solving the Problem

[0005] According to one embodiment of the present disclosure, an image forming apparatus is provided. The image forming apparatus includes a mounting portion detachably mounting a printing cartridge having a memory element and an element substrate having a plurality of terminals, a first apparatus substrate supplying a signal to the element substrate, a second apparatus substrate relaying the signal supplied from the first apparatus substrate and supplying it to the element substrate, and a connection terminal portion having a plurality of connection terminals connected to each of the plurality of terminals. The second apparatus substrate includes a switching circuit that switches between a state of supplying the signal supplied from the first apparatus substrate to the element substrate (ON state) and a state of not supplying it (OFF state).

Brief Description of the Drawings

[0006]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Embodiments for Carrying Out the Invention

[0007] A. First Embodiment: FIG. 1 is an explanatory diagram showing a schematic configuration of an image forming system 1000 as an embodiment of the present disclosure. The image forming system 1000 includes an image forming apparatus 20, a plurality of print cartridges 100 detachably attached to the image forming apparatus 20, and a computer 90. The image forming apparatus 20 is an inkjet printer that discharges ink as a printing material onto a printing medium PA to perform printing. The image forming apparatus 20 is connected to the computer 90 via a connector 80 so as to be capable of data communication. The print cartridge 100 is an ink cartridge that stores ink as a printing material for performing image formation.

[0008] The image forming apparatus 20 includes a sub-scanning feed mechanism, a main-scanning feed mechanism, a head drive mechanism, and a first device substrate 40 as a main control device. The sub-scanning feed mechanism includes a paper feed motor 22 and a platen 26, and conveys the printing medium PA in the sub-scanning direction by transmitting the rotation of the paper feed motor 22 to the platen 26. The main-scanning feed mechanism includes a carriage motor 32, a pulley 38, a drive belt 36 stretched between the carriage motor 32 and the pulley 38, and a sliding shaft 34 provided in parallel with the axis of the platen 26. The sliding shaft 34 slidably holds a carriage 30 fixed to the drive belt 36. The rotation of the carriage motor 32 is transmitted to the carriage 30 via the drive belt 36, and the carriage 30 reciprocates in the main-scanning direction, which is the axial direction of the platen 26, along the sliding shaft 34. The head drive mechanism includes the carriage 30. The carriage 30 includes a mounting portion 4 to which the print cartridge 100 can be mounted, a head 5 that discharges ink, a liquid introduction portion 6 described later, a connection terminal portion 400 described later, and a second device substrate 50 described later. The head drive mechanism drives the head 5 of the carriage 30 to discharge ink onto the printing medium PA. By discharging ink onto the printing medium PA, an image is formed on the printing medium PA.

[0009] The first device substrate 40 controls the above-described respective mechanisms to realize printing processing. The first device substrate 40 is electrically connected to a second device substrate 50, which will be described later, of the mounting portion 4 via a bus 49. The first device substrate 40 receives, for example, a user's print job via a computer 90, and based on the content of the received print job, controls the above-described respective mechanisms to execute a printing operation. Further, in a state where the print cartridge 100 is mounted on the mounting portion 4, the first device substrate 40 exchanges various signals with an element substrate, which will be described later, that the print cartridge 100 has.

[0010] The mounting portion 4 of the carriage 30 can detachably mount a plurality of print cartridges 100. In the present embodiment, the number of print cartridges 100 that can be mounted on the mounting portion 4 is four. Different colors or types of ink are stored in the four print cartridges 100. When the plurality of print cartridges 100 are used separately, reference numerals 100A, 100B, 100C, and 100D are used. The four print cartridges 100A to 100D are respectively mounted at predetermined mounting positions of the mounting portion 4. Note that in other embodiments, the number of print cartridges 100 that can be mounted on the mounting portion 4 is not limited to four, and may be less than or more than four. The image forming apparatus 20 further includes an operation unit 70 for a user to perform various settings of the image forming apparatus 20 and check the status of the image forming apparatus 20. The operation unit 70 has a display unit 72 for displaying various information such as the status of the image forming apparatus 20.

[0011] Note that in the present embodiment, the image forming system 1000 is of a type called an on-carriage in which the print cartridge 100 is mounted on the mounting portion 4 of the carriage 30, but is not limited thereto. For example, the image forming system 1000 may be of a type called an off-carriage in which the print cartridge 100 is mounted on a mounting portion located at a position different from the carriage 30.

[0012] With reference to FIGS. 2 and 3, the configuration of the printing cartridge 100 will be described. FIG. 2 is a first perspective view showing the configuration of the printing cartridge 100. FIG. 3 is a second perspective view showing the configuration of the printing cartridge 100. In FIGS. 2 and later, X-axis, Y-axis, and Z-axis that are orthogonal to each other are added as necessary. In FIG. 2, the directions in which the arrows of the X-axis, Y-axis, and Z-axis point indicate the positive directions along the X-axis, Y-axis, and Z-axis, respectively. The positive directions along the X-axis, Y-axis, and Z-axis are defined as the +X direction, +Y direction, and +Z direction, respectively. The directions opposite to the directions in which the arrows of the X-axis, Y-axis, and Z-axis point are the negative directions along the X-axis, Y-axis, and Z-axis, respectively. The negative directions along the X-axis, Y-axis, and Z-axis are defined as the -X direction, -Y direction, and -Z direction, respectively. Those that are positive or negative in the directions along the X-axis, Y-axis, and Z-axis are collectively referred to as the X direction, Y direction, and Z direction, respectively. The same applies to the figures and descriptions shown hereinafter. The directions of the XYZ axes drawn in other figures correspond to the directions of the XYZ axes in FIG. 2. The orientations of the X-axis, Y-axis, and Z-axis with respect to the printing cartridge 100 are based on the state in which the image forming apparatus 20 is arranged on a horizontal plane parallel to the X direction and the Y direction, and the printing cartridge 100 is mounted on the image forming apparatus 20.

[0013] As shown in FIGS. 2 and 3, the external shape of the printing cartridge 100 is substantially a rectangular parallelepiped shape. As shown in FIG. 2, the printing cartridge 100 includes a main body 101 that forms an outer shell, and an element substrate 120 attached to the front wall 101wf of the main body 101. The main body 101 includes a front wall 101wf that is a wall on the -Y direction side and a bottom wall 101wb that is a wall on the +Z direction side. The main body 101 also has a liquid storage portion 150 for storing ink as a liquid. The front wall 101wf intersects, and in this embodiment, is substantially orthogonal to the bottom wall 101wb. The bottom wall 101wb of the main body 101 includes a liquid supply portion 104 that supplies the liquid in the liquid storage portion 150 to the carriage 30 when the printing cartridge 100 is mounted on the mounting portion 4 of the carriage 30. The liquid supply portion 104 communicates with the liquid storage portion 150. The opening 104op of the liquid supply portion 104 is sealed by a film 104f. By mounting the printing cartridge 100 on the carriage 30, the film 104f is broken, and a liquid introduction portion 6 (described later) provided in the carriage 30 is inserted into the liquid supply portion 104. The ink stored in the liquid storage portion 150 is supplied to the head 5 of the image forming apparatus 20 through the liquid introduction portion 6. As the ink in the liquid storage portion 150 is consumed, air is introduced into the liquid storage portion 150 from an air release hole (not shown).

[0014] FIG. 4 is a first diagram showing the configuration of the element substrate 120 according to the present embodiment. FIG. 5 is a second diagram showing the configuration of the element substrate 120. As shown in FIG. 4, the element substrate 120 has a terminal group 290 on the front surface 120fa, and a non-volatile memory element 130 on the back surface 120fb as shown in FIG. 5. As shown in FIG. 4, the terminal group 290 has a plurality of terminals 211, 212, 213, 214, 215, 231.

[0015] Of the plurality of terminals 211, 212, 213, 214, 215, 231, the terminals 211, 212, 213, 214, 215 excluding the terminal 231 are terminals for the memory element 130. The terminal 211 is a data terminal. The terminal 211 is used to transmit and receive various data such as ink color data and consumption data regarding the consumption amount of the liquid stored in each print cartridge 100 between the memory element 130 and the image forming apparatus 20. That is, the terminal 211 is a data terminal that receives a data signal supplied from the first device substrate 40. The terminal 212 is a power supply terminal that receives the supply of a power supply voltage as a signal supplied from the first device substrate 40. The terminal 213 is a reset terminal that receives a reset signal supplied from the first device substrate 40. The terminal 214 is a ground terminal. The terminal 215 is a clock terminal that receives a clock signal supplied from the first device substrate 40.

[0016] The terminal 231 is a switching terminal. The terminal 231 is used to control the operation of a switching circuit 58 that switches whether to supply a signal supplied from the first device substrate 40 to the element substrate 120 according to the connection state with the substrate terminal 531 and the connection state between the terminal 214 electrically connected to the terminal 231 and the substrate terminal 514. The switching circuit 58 is provided on a second device substrate 50 of the image forming apparatus 20 described later. Details of the switching circuit 58 will be described later. The ground terminal 214 and the switching terminal 231 are electrically connected. In the present embodiment, the ground terminal 214 and the switching terminal 231 are electrically connected by an electrical wiring LC1 formed on the surface 120fa. Since the terminals 214, 231 electrically connected by the electrical wiring LC1 are adjacent to each other, the electrical wiring LC1 can be shortened.

[0017] Each of the terminals 211, 212, 213, 214, 215, 231 is formed in a substantially rectangular shape. At the center of each of the terminals 211, 212, 213, 214, 215, 231, there is a contact point cp that contacts a connection terminal described later.

[0018] Each of the terminals 211, 212, 213, 214, 215 of the terminal group 290 is connected to the memory element 130 via wiring pattern layers on the front and back surfaces of an element substrate 120 (not shown) and via through-holes disposed in the element substrate 120.

[0019] The memory element 130 shown in FIG. 5 is a NAND-type flash memory. In other embodiments, the memory element 130 may be a memory such as a NOR-type flash memory or an EEPROM. The memory element 130 includes an element control unit 136 and a memory unit 138 composed of a plurality of memory cells. Each memory cell constituting the memory unit 138 can store 1-bit data. Further, the memory element 130 can perform data communication with the first device substrate 40 of the image forming apparatus 20.

[0020] FIG. 6 is a diagram showing a state in which the print cartridge 100 is mounted on the mounting portion 4 of the carriage 30. FIG. 7 is a first diagram showing the connection terminal portion 400. FIG. 8 is a second diagram showing the connection terminal portion 400.

[0021] As shown in FIG. 6, the carriage 30 includes a mounting portion 4, a head 5, a liquid introduction portion 6, a connection terminal portion 400, and a second device substrate 50. The mounting portion 4 forms a mounting chamber 65 for mounting the print cartridge 100. The head 5 includes a plurality of nozzles and a plurality of piezoelectric elements, and ejects ink droplets from each nozzle according to the voltage applied to each piezoelectric element to form dots on the print medium PA. The liquid introduction portion 6 is disposed on the head 5 and supplies ink from the print cartridge 100 to the head 5. In the present embodiment, four liquid introduction portions 6 are provided corresponding to the number of the print cartridges 100A to 100D. The connection terminal portion 400 electrically connects the second device substrate 50 and the element substrate 120 of the print cartridge 100. Four connection terminal portions 400 are provided corresponding to the number of the print cartridges 100A to 100D. As shown in FIG. 8, the second device substrate 50 has a second control portion 54. The second control portion 54 cooperates with the first device substrate 40 to perform control related to the print cartridge 100. The second device substrate 50 relays various signals such as data signals, clock signals, reset signals, and power supply voltages supplied from the first device substrate 40 and supplies them to the element substrate 120.

[0022] As shown in FIG. 6, the print cartridge 100 is mounted on the mounting portion 4 of the image forming apparatus 20 by being inserted in the +Z direction. In this way, the print cartridge 100 is detachably mounted on the image forming apparatus 20. Further, when the print cartridge 100 is correctly mounted on the image forming apparatus 20, the element substrate 120 is electrically connected to the first device substrate 40 of the image forming apparatus 20 via the connection terminal portion 400, the second device substrate 50, and the bus 49.

[0023] As shown in FIG. 7, the connection terminal portion 400 includes a terminal holding portion 405 and a plurality of terminal forming members 403 having conductivity and elasticity and held by the terminal holding portion 405. The terminal holding portion 405 has a plurality of slits 301. The terminal forming member 403 is fitted into the slit 301. In the present embodiment, for each connection terminal portion 400, six terminal forming members 403 are provided, which is the same as the number of terminals in the terminal group 290.

[0024] As shown in FIG. 8, the terminal forming member 403 is a member that electrically connects the terminal group 290 and the board terminal 590 of the second device board 50. The board terminals 590 are provided for each mounting chamber 65. Also, six board terminals 590 are provided corresponding to the number of terminals in the terminal group 290. When the six board terminals 590 are used separately, the symbols "511", "512", "513", "514", "515", "531" are used. Among the terminal forming members 403, the portion protruding toward the mounting chamber 65 forms a plurality of connection terminals 490 that come into contact with the respective ones of the plurality of terminals 211 to 215 and 231 of the terminal group 290. Also, among the terminal forming members 403, the portion protruding toward the second device board 50 forms relay terminals 439 that come into contact with the board terminals 590. When the six terminal forming members 403 are used separately, "A" to "F" are appended to the end. Also, when the six connection terminals 490 are used separately, the symbols "411", "412", "413", "414", "415", "431" are used. Also, when the six relay terminals 439 are used separately, the symbols "411a", "412a", "413a", "414a", "415a", "431a" are used. Also, when the six board terminals 590 are used separately, the symbols "511", "512", "513", "514", "515", "531" are used.

[0025] The terminal forming member 403A having the connection terminal 411 and the relay terminal 411a electrically connects the terminal 211 of the data terminal and the board terminal 511. The terminal forming member 403B having the connection terminal 412 and the relay terminal 412a electrically connects the terminal 212 of the power supply terminal and the board terminal 512. The terminal forming member 403C having the connection terminal 413 and the relay terminal 413a electrically connects the terminal 213 of the reset terminal and the board terminal 513. The terminal forming member 403D having the terminal 414 of the connection terminal and the relay terminal 414a electrically connects the terminal 214 of the ground terminal and the board terminal 514. The terminal forming member 403E having the connection terminal 415 and the relay terminal 415a electrically connects the terminal 215 of the clock terminal and the board terminal 515. The terminal forming member 403F having the connection terminal 431 and the relay terminal 431a electrically connects the terminal 231 of the switching terminal and the board terminal 531.

[0026] FIG. 9 is a diagram showing the configuration of the image forming apparatus 20 together with one print cartridge 100. The memory element 130 of the element substrate 120 includes an element control unit 136 and a storage unit 138. The element control unit 136 controls the operation of the memory element 130. For example, the element control unit 136 performs a data writing operation and a reading operation to / from the storage unit 138 in response to a command transmitted from the image forming apparatus 20.

[0027] As described above, the image forming apparatus 20 includes a display unit 72, a first apparatus substrate 40 that supplies a signal to the element substrate 120, and a second apparatus substrate 50 that relays the signal supplied from the first apparatus substrate 40 and supplies it to the element substrate 120.

[0028] The first apparatus substrate 40 includes a power supply 42, a first control unit 44 as a processor, and a first apparatus storage unit 46. The power supply 42 generates a power supply voltage VDD. The power supply voltage VDD is a normal power supply voltage used for a logic circuit, and is, for example, a rated 3.3V. The first control unit 44 controls the operation of the image forming apparatus 20 and generates various signals for supplying to the element substrate 120. The first apparatus storage unit 46 stores various programs executed by the first control unit 44 and stores various information about the print cartridge 100, such as the remaining amount of the printing material of the print cartridge 100.

[0029] The second apparatus substrate 50 includes a second control unit 54 as a processor and a second apparatus storage unit 56. The second control unit 54 controls the operation of the second apparatus substrate 50. The second apparatus storage unit 56 stores various programs for controlling the operation of the second apparatus substrate 50.

[0030] FIG. 10 is a diagram for further explaining the image forming apparatus 20. The second apparatus substrate 50 of the image forming apparatus 20 further includes a communication start circuit 55, a switching circuit 58, and a plurality of lines LN for electrically connecting the image forming apparatus 20 and the element substrate 120. The plurality of lines LN include a data line LSDA, a clock line LSCK, a power supply line LVDD, a reset line LRST, a ground line LVSS, and a first connection line LM.

[0031] The data line LSDA is a line through which data signals such as the remaining amount of the printing material flow. The end of the data line LSDA is connected to the substrate terminal 511. The reset line LRST is a line through which a reset signal flows. The end of the reset line LRST is connected to the substrate terminal 513. The clock line LSCK is a line through which a clock signal flows. The end of the clock line LSCK is connected to the substrate terminal 515. The power supply line LVDD is a line to which a power supply voltage is applied. The end of the power supply line LVDD is connected to the substrate terminal 512. The ground line LVSS is a grounded line. The end of the ground line LVSS is connected to the substrate terminal 514. The first connection line LM is a line used for the operation of the switching circuit 58. The end of the first connection line LM is connected to the substrate terminal 531.

[0032] The communication start circuit 55 includes a first transistor 55a and a second transistor 55b. The first transistor 55a is a switch disposed on the power supply line LVDD. In the present embodiment, the first transistor 55a is a P-channel transistor, specifically, a P-channel MOSFET. The second transistor 55b is a switch disposed on the ground line LVSS. In the present embodiment, the second transistor 55b is an N-channel transistor, specifically, an N-channel MOSFET.

[0033] When the communication start circuit 55 is in an ON state when the first device substrate 40 starts communication with the element substrate 120, it is turned on under the control of the second control unit 54, and the power supply line LVDD and the ground line LVSS are both in a conductive state. Specifically, when the second control unit 54 receives a signal for starting communication from the first device substrate 40 via the bus 49, the second control unit 54 applies a low-level voltage to the gate of the first transistor 55a and a high-level voltage to the gate of the second transistor 55b, thereby switching the first transistor 55a and the second transistor 55b from the OFF state to the ON state. Since the communication start circuit 55 can suppress the power supply voltage from being always applied to the element substrate 120 in the mounted state, the service life of the element substrate 120 can be extended. Note that the communication start circuit 55 may be omitted.

[0034] The switching circuit 58 switches between an ON state in which the power supply voltage as a signal supplied from the first device substrate 40 is supplied to the element substrate 120 and an OFF state in which it is not supplied when the communication start circuit 55 is in the ON state. The switching circuit 58 includes a transistor 581 and a pull-up resistor 583. The transistor 581 is a P-channel type transistor, specifically, a P-channel type MOSFET. The transistor 581 is disposed between an end portion of the power supply line LVDD connected to the first transistor 55a and the substrate terminal 513. The gate G of the transistor 581 is electrically connected to the first connection terminal 431 by the relay line LCN and the first connection line LM. One end 584 of the pull-up resistor 583 is connected to a portion between the transistor 581 and the power supply 42 in the power supply line LVDD, specifically, a portion between the first transistor 55a and the transistor 581. The other end of the pull-up resistor 583 is connected to the first connection line LM. As described above, the pull-up resistor 583 is disposed between the gate G of the transistor 581 and the source S connected to the power supply 42.

[0035] Here, among the plurality of terminals 211 to 215 and 231 provided on the element substrate 120, the switching terminal 231 is also referred to as the first terminal 231, the ground terminal 214 is also referred to as the second terminal 214, and the power supply terminal 212 is also referred to as the third terminal 212. Also, as shown in FIGS. 7 and 8, the connection terminal 431 corresponding to the first terminal 231 is also referred to as the first connection terminal 431. Also, the connection terminal 414 corresponding to the second terminal 214 is also referred to as the second connection terminal 414. Also, the connection terminal 412 corresponding to the third terminal 212 is also referred to as the third connection terminal 412.

[0036] As described above, the second device substrate 50 has the first connection line LM connected to the first connection terminal 431. Also, as described above, the gate G of the transistor 581 is electrically connected to the first connection line LM.

[0037] In the mounted state where the printing cartridge 100 is mounted on the mounting portion 4 and when the communication start circuit 55 is in the ON state, in the following ON setting state, the transistor 581 is in the ON state. When the transistor 581 is in the ON state, the power supply voltage as a signal supplied from the first device substrate 40 is supplied to the element substrate 120 via the power supply line LVDD. The ON setting state means that the second terminal 214 and the second connection terminal 414 are in a conductive state by contacting each other, and the first terminal 231 and the first connection terminal 431 are in a conductive state by contacting each other. In the ON setting state, since the first terminal 231 is conductive with the second terminal 214 which is a ground terminal via the electrical wiring LC1, it becomes a low-level voltage. As a result, the first connection line LM which is conductive with the first terminal 231 via the connection terminal 431 also becomes low-level, so a low-level voltage is applied to the gate G of the transistor 581. In the ON setting state, since a low-level voltage is applied to the gate G of the transistor 581, the transistor 581 is in the ON state, and the supply of the power supply voltage as a signal via the third connection terminal 412 to the third terminal 212 is started.

[0038] On the other hand, in the following OFF setting state, the transistor 581 is in the OFF state. When the transistor 581 is in the OFF state, the supply of the power supply voltage as a signal supplied from the first device substrate 40 to the element substrate 120 via the power supply line LVDD is cut off. The OFF setting state is at least one of a state where the second terminal 214 and the second connection terminal 414 are not conducting due to poor contact between the second terminal 214 and the second connection terminal 414, and a state where the first terminal 231 and the first connection terminal 431 are not conducting due to poor contact between the first terminal 231 and the first connection terminal 431. In the OFF setting state, the first terminal 231 is not conducting with the second terminal 214 which is a ground terminal. As a result, a high-level voltage is applied to the gate G of the transistor 581 by the pull-up resistor 583 disposed between the gate G and the source S of the transistor 581, so that the transistor 581 is in the OFF state. Therefore, the supply of the power supply voltage as a signal via the third connection terminal 412 to the third terminal 212 is cut off.

[0039] As described above, in the mounted state, the switching circuit 58 is in the OFF state in at least one of the cases where the second terminal 214 and the second connection terminal 414 are not conducting and the case where the first terminal 231 and the first connection terminal 431 are not conducting, thereby cutting off the supply of the power supply voltage which is a signal via the third connection terminal 412 to the third terminal 212.

[0040] According to the first embodiment described above, since the switching circuit 58 can switch the signal to either an ON state in which the signal is supplied to the element substrate 120 or an OFF state in which the signal is not supplied, when the terminal group 290 of the element substrate 120 and the connection terminal 490 of the image forming apparatus 20 are not electrically connected, the OFF state can be set to block the supply of the signal to the element substrate 120. Thereby, the possibility of problems such as the element substrate 120 being damaged can be reduced. In particular, according to the first embodiment described above, the second terminal 214 is the terminal 214 of the ground terminal, and the third terminal 212 is the terminal 212 of the power supply terminal. Thereby, in a state where the conduction between the terminal 214 and the corresponding connection terminal 414 is not established, the OFF state is entered and the supply of the power supply voltage to the element substrate 120 is blocked. Thereby, the insertion and removal of live wires can be prevented, and the possibility of the element substrate 120 being damaged can be reduced. Further, in addition to the terminals 211, 212, 213, 214, 215 for the memory element 130, by adding the terminal 231 of one switching terminal, a configuration can be achieved in which a control signal for switching the switching circuit 58 between the ON state and the OFF state can be supplied to the switching circuit 58.

[0041] Also according to the first embodiment described above, as shown in FIG. 10, the switching circuit 58 can be configured with a simple circuit configuration including a P-channel transistor 581 and a pull-up resistor 583. Also according to the first embodiment described above, as shown in FIG. 10, by electrically connecting the gate G of the P-channel transistor 581 to the first connection line LM, the switching circuit 58 for easily switching between the ON state and the OFF state can be configured.

[0042] B. Second Embodiment: FIG. 11 is a diagram for explaining the image forming apparatus 20a in the second embodiment. The difference from the image forming apparatus 20 in the first embodiment shown in FIG. 10 above is the configuration of the switching circuit 58a. The switching circuit 58a of the second embodiment includes a pull-up resistor 585 and a comparator 587. Since the other configurations are the same in the first embodiment and the second embodiment, the same reference numerals are given to the same configurations and the description is appropriately omitted.

[0043] The first input terminal 588 of the comparator 587 is connected to the second control unit 54. The second control unit 54 sets a reference potential at the input terminal 588. The second input terminal 589 of the comparator 587 is connected to the first connection terminal 431 via the first connection line LM. The output terminal 591 of the comparator 587 is connected to the gate G of the transistor 581. The reference potential is set, for example, between 0V and the voltage 3.3V of the power supply 42, and may be a potential about half of the power supply voltage, or may be set to a potential smaller than half. For example, in the present embodiment, the reference potential is set to any value in the range of 0.1V or more and 0.2V or less.

[0044] When the voltage of the second input terminal 589 of the comparator 587 is lower than the reference potential of the first input terminal 588, the comparator 587 outputs a low-level voltage to the output terminal 591. Thereby, the transistor 581 is turned on. On the other hand, when the potential of the second input terminal 589 of the comparator 587 is higher than the reference potential of the first input terminal 588, the comparator 587 outputs a high-level voltage to the output terminal 591. Thereby, the transistor 581 is turned off.

[0045] In the pull-up resistor 585, one end is connected to the power supply line LVDD, and the other end is connected to the second input terminal 589 of the transistor 581. That is, the pull-up resistor 585 is disposed between the second input terminal 589 of the transistor 581 and the power supply line LVDD.

[0046] In the mounted state where the printing cartridge 100 is mounted on the mounting portion 4 and when the communication start circuit 55 is in the ON state, in the case of the ON setting state similar to the first embodiment, the transistor 581 is in the ON state. In the ON setting state, since the first terminal 231 is electrically connected to the second terminal 214, which is the ground terminal, via the electrical wiring LC1, it becomes a low-level voltage. As a result, the first connection line LM that is electrically connected to the first terminal 231 via the connection terminal 431 also becomes low-level, specifically lower than the reference potential. Thereby, since the potential of the second input terminal 589 becomes lower than the reference potential of the first input terminal 588, a low-level voltage is output to the output terminal 591. When a low-level voltage is output to the output terminal 591, the transistor 581 becomes in the ON state, and the supply of the power supply voltage as a signal via the third connection terminal 412 to the third terminal 212 is started.

[0047] On the other hand, in the case of the above-described OFF setting state, the power supply voltage is supplied to the second input terminal 589 by the pull-up resistor 585. Thereby, since the second input terminal 589 becomes a high-level potential higher than the reference potential, a high-level voltage is output to the output terminal 591. When a high-level voltage is output to the output terminal 591, the transistor 581 becomes in the OFF state, and the supply of the power supply voltage as a signal via the third connection terminal 412 to the third terminal 212 is cut off.

[0048] According to the second embodiment, in that it has the same configuration as the first embodiment, the same effects are achieved. For example, since the switching circuit 58a shown in FIG. 11 can switch to either an ON state in which a signal is supplied to the element substrate 120 or an OFF state in which the signal is not supplied, when the terminal group 290 of the element substrate 120 and the connection terminal 490 of the image forming apparatus 20 are not electrically connected, the signal supply to the element substrate 120 can be blocked by setting it to the OFF state. Thereby, the possibility of problems such as the element substrate 120 being damaged can be reduced. Further, according to the second embodiment, the switching circuit 58a can be formed with a simple circuit configuration including a P-channel type transistor 581, a comparator 587, and a pull-up resistor 585.

[0049] C. Other Embodiments: C-1. Other Embodiment 1: In each of the above embodiments, the third terminal was the terminal 212 of the power supply terminal. However, the third terminal may be at least one of the terminal 212 of the power supply terminal, the terminal 211 of the data terminal, the terminal 213 of the reset terminal, and the terminal 215 of the clock terminal. That is, the signal to be switched between the ON state supplied to the element substrate 120 and the OFF state not supplied by the switching circuits 58 and 58a may be at least one of the power supply voltage, the data signal, the reset signal, and the clock signal. In this case, the second terminal is the terminal 214 of the ground terminal as in each of the above embodiments. For example, as shown in FIG. 10, at least one of the data line LSDA, the clock line LSCK, the power supply line LVDD, and the reset line LRST may have a transistor 581 disposed thereon, and a pull-up resistor 583 may be disposed between the source S of the transistor 581 and the first connection line LM. By doing so, in at least one of the cases where the first terminal and the first connection terminal are not conducting and the second terminal and the second connection terminal are not conducting, the OFF state can be achieved, and the supply of the signal to the third terminal via the third connection terminal can be interrupted. Specifically, in a state where the conduction between the terminal 214 of the ground terminal and the corresponding connection terminal 414 is not established, the OFF state is achieved and the supply of the signal to the third terminal via the third connection terminal is interrupted. Thereby, it is possible to prevent a signal from being supplied to the data terminal, the reset terminal, or the clock terminal in a non-grounded state, and thus the possibility of the element substrate 120 being damaged can be reduced.

[0050] C-2. Other Embodiment 2: In each of the above embodiments, as shown in FIG. 4, the first terminal 231 and the second terminal 214 connected by the electrical wiring LC1 were arranged adjacent to each other. However, they may not be arranged adjacent to each other.

[0051] C-3. Other Embodiment 3: In each of the above embodiments, as shown in FIG. 1, the image forming apparatus 20 is an inkjet printer, and the printing material accommodated in the printing cartridge 100 is ink. However, the present invention is not limited to this, and any apparatus for image formation and printing cartridge may be used. For example, the image forming apparatus 20 may be an apparatus that forms an image using a printing cartridge having toner as a printing material. Further, for example, the image forming apparatus 20 may be an apparatus that forms an image using a printing cartridge having a tape as a printing material.

[0052] D. Other forms: The present disclosure is not limited to the above-described embodiments, and can be realized in various forms without departing from the gist thereof. For example, the present disclosure can also be realized by the following aspects. The technical features in the above embodiments corresponding to the technical features in each of the following aspects can be appropriately replaced or combined in order to solve part or all of the problems of the present disclosure, or to achieve part or all of the effects of the present disclosure. Further, if the technical feature is not described as essential in this specification, it can be appropriately deleted.

[0053] (1) According to one embodiment of the present disclosure, an image forming apparatus is provided. This image forming apparatus includes a mounting portion for removably mounting a printing cartridge having a memory element and an element substrate with a plurality of terminals, a first device substrate for supplying a signal to the element substrate, a second device substrate for relaying the signal supplied from the first device substrate and supplying it to the element substrate, and a connection terminal portion having a plurality of connection terminals each connected to one of the plurality of terminals. The second device substrate includes a switching circuit for switching between an ON state in which the signal supplied from the first device substrate is supplied to the element substrate and an OFF state in which it is not supplied. According to this embodiment, according to this embodiment, since the switching circuit can switch between an ON state in which a signal is supplied to the element substrate and an OFF state in which it is not supplied, when the terminals of the element substrate and the connection terminals of the image forming apparatus are not electrically connected, the signal supply to the element substrate can be blocked by setting it to the OFF state. Thereby, the possibility of problems such as the element substrate being damaged can be reduced.

[0054] (2) In the above embodiment, the plurality of terminals include a first terminal, a second terminal, and a third terminal. The plurality of connection terminals include a first connection terminal corresponding to the first terminal, a second connection terminal corresponding to the second terminal, and a third connection terminal corresponding to the third terminal. The switching circuit is in an OFF state when at least one of the cases where the first terminal and the first connection terminal are not electrically connected and the second terminal and the second connection terminal are not electrically connected in the mounted state where the printing cartridge is mounted on the mounting portion. The supply of the signal to the third terminal via the third connection terminal may be blocked. In this embodiment, when at least one of the cases where the first terminal and the first connection terminal are not electrically connected and the second terminal and the second connection terminal are not electrically connected, the supply of the signal to the third terminal via the third connection terminal can be blocked by setting it to the OFF state.

[0055] (3) In the above-described embodiment, the switching circuit may include a P-channel transistor and a pull-up resistor. According to this embodiment, a switching circuit can be formed with a simple circuit configuration including a P-channel transistor and a pull-up resistor.

[0056] (4) In the above-described embodiment, the switching circuit may include a P-channel transistor and a comparator. According to this embodiment, a switching circuit can be formed with a simple circuit configuration including a P-channel transistor and a comparator.

[0057] (5) In the above-described embodiment, the second terminal may be a ground terminal, and the third terminal may be a power supply terminal that receives power supply. According to this embodiment, in a state where conduction between the ground terminal and the corresponding connection terminal is not established, it is in the OFF state and the supply of the power supply voltage is interrupted. Thereby, it is possible to prevent the insertion and removal of the live wire, and thus the possibility of the element substrate being damaged can be reduced.

[0058] (6) In the above-described embodiment, the second terminal may be a ground terminal, and the third terminal may be at least one of a data terminal, a reset terminal, and a clock terminal. According to this embodiment, in a state where conduction between the ground terminal and the corresponding connection terminal is not established, it is in the OFF state, and the supply of a signal to the third terminal via the third connection terminal can be interrupted. Thereby, it is possible to prevent a signal from being supplied to the data terminal, the reset terminal, or the clock terminal in a non-grounded state, and thus the possibility of the element substrate being damaged can be reduced.

[0059] (7) In the above-described embodiment, the second device substrate may have a first connection line connected to the first connection terminal, and the gate of the P-channel transistor may be electrically connected to the first connection line. According to this embodiment, by electrically connecting the gate of the P-channel transistor to the first connection line, a switching circuit for easily switching between the ON state and the OFF state can be formed.

[0060] The present disclosure can also be implemented in various forms other than those described above. For example, it can be implemented in the form of an image forming system including an image forming apparatus and a printing cartridge, a control method of the image forming apparatus, and a non-transitory storage medium storing a computer program for realizing the control method.

Explanation of Reference Numerals

[0061] 4... Mounting portion, 5... Head, 6... Liquid introduction portion, 20, 20a... Image forming apparatus, 22... Motor, 26... Platen, 30... Carriage, 32... Carriage motor, 34... Sliding shaft, 36... Driving belt, 38... Pulley, 40... First device substrate, 42... Power supply, 44... First control unit, 46... Bus, 49... First device storage unit, 50... Second device substrate, 54... Second control unit, 55... Communication start circuit, 55a... First transistor, 55b... Second transistor, 56... Second device storage unit, 58, 58a... Switching circuit, 65... Mounting chamber, 70... Operation unit, 72... Display unit, 80... Connector, 90... Computer, 100, 100A to 100D... Printing cartridge, 101... Main body, 101wb... Bottom wall, 101wf... Front wall, 104... Liquid supply unit, 104f... Film, 104op... Opening, 120... Element substrate, 120fa... Front surface, 120fb... Back surface, 130... Memory element, 136... Element control unit, 138... Storage unit, 150... Liquid storage portion, 211 to 215, 231... Terminals, 290... Terminal group, 301... Slit, 400... Connection terminal portion, 403, 403A to 403F... Terminal forming members, 411 to 415, 431... Connection terminals, 411a to 415a, 431a... Relay terminals, 439... Relay terminal, 490... Connection terminal, 511 to 515, 531... Substrate terminals, 581... Transistor, 583, 585... Pull-up resistors, 584... One end, 587... Comparator, 588... First input terminal, 589... Second input terminal, 590... Substrate terminal, 591... Output terminal, 1000... Image forming system, G... Gate, LC1... Electrical wiring, LCN... Relay line, LM... First connection line, LN... Line, LRST... Reset line, LSCK... Clock line, LSDA... Data line, LVDD... Power supply line, PA... Printing medium, S... Source, VDD... Power supply voltage, cp... Contact

Claims

1. An image forming apparatus, comprising: a mounting portion detachably mounting a printing cartridge having a memory element and an element substrate having a plurality of terminals; a first device substrate for supplying a signal to the element substrate; a second device substrate for relaying the signal supplied from the first device substrate and supplying it to the element substrate; a connection terminal portion having a plurality of connection terminals connected to each of the plurality of terminals, wherein the second device substrate includes a switching circuit for switching the signal supplied from the first device substrate to either an ON state of supplying the signal to the element substrate or an OFF state of not supplying the signal, the image forming apparatus.

2. The image forming apparatus according to claim 1, wherein the plurality of terminals include a first terminal, a second terminal, and a third terminal, the plurality of connection terminals include a first connection terminal corresponding to the first terminal, a second connection terminal corresponding to the second terminal, and a third connection terminal corresponding to the third terminal, wherein the switching circuit, in a mounted state where the printing cartridge is mounted on the mounting portion, when at least one of a case where the first terminal and the first connection terminal are not electrically connected and a case where the second terminal and the second connection terminal are not electrically connected occurs, enters the OFF state to cut off the supply of the signal to the third terminal via the third connection terminal, the image forming apparatus.

3. The image forming apparatus according to claim 2, wherein the switching circuit includes a P-channel type transistor and a pull-up resistor, the image forming apparatus.

4. The image forming apparatus according to claim 1 or claim 2, wherein the switching circuit includes a P-channel type transistor and a comparator, the image forming apparatus.

5. The image forming apparatus according to claim 2, wherein the second terminal is a ground terminal, and the third terminal is a power supply terminal for receiving power supply, the image forming apparatus.

6. The image forming apparatus according to claim 2, wherein the second terminal is a ground terminal, and the third terminal is at least one of a data terminal, a reset terminal, and a clock terminal, the image forming apparatus.

7. The image forming apparatus according to claim 3, wherein the second device substrate has a first connection line connected to the first connection terminal, and the gate of the P-channel type transistor is electrically connected to the first connection line, the image forming apparatus.

Images