Recording device, determination method, and program

Abstract

This allows for the determination of whether the connection status of multiple connections related to the logic ground is normal or not. [Solution] A recording device in which a recording head can be detachably mounted, wherein a diode and an electronic circuit are mounted on the recording head, the anode of the diode is connected to a constant current source that supplies a constant current to the diode and a voltage detection circuit that detects the voltage of the anode with reference to the ground of the main body of the recording device, the cathode of the diode and the ground terminal of the electronic circuit can be connected to ground via each of the number of mounted ground connection parts, and the recording device includes determination means for determining the electrical connection state of the number of mounted ground connection parts based on the voltage of the anode detected by the voltage detection circuit when a constant current is supplied from the constant current source to ground through the diode and a test current is supplied from the ground terminal of the electronic circuit to ground.

Description

Technical Field

[0001] The present disclosure relates to a recording apparatus capable of detachably mounting a recording head that discharges liquid, a method for determining an electrical connection state of a ground connection portion, and a program related thereto.

Background Art

[0002] There are known recording apparatuses configured such that a user can attach and detach a recording head from the main body of the recording apparatus during replacement or maintenance of the recording head or the like. In such a recording apparatus, when the recording head is attached to the main body of the recording apparatus, it is necessary that each terminal provided in the recording apparatus main body and each terminal connected to an electric circuit in the recording head be properly connected. Therefore, Patent Document 1 discloses a technique for determining whether or not the terminals on the recording apparatus side and the terminals on the recording head side are electrically properly connected.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] When a recording head is mounted on a recording device, the ground of the recording device body and the ground of the recording head are interconnected. In particular, there are configurations in which the ground of the recording device body and the ground for the logic circuit of the recording head (also called the "logic ground") Vss are connected not by a single connection point (a pair of terminals on the recording device side and terminals on the recording head side) but by multiple connection points. In such a configuration, if there is a connection failure in some of the connection points, the potential of the logic ground Vss of the recording head will fluctuate by several mV. In other words, in a configuration in which the ground of the recording device body and the logic ground Vss of the recording head are connected by n connection points, this occurs if there is a connection failure in 1 to (n-1) connection points. Patent Document 1 detects connection failures of the logic ground Vss based on the voltage of the anode of a temperature-sensing diode sensor provided inside the recording head in order to determine the connection state. Here, the forward voltage Vf of the diode sensor may have a variation of several tens of mV, which causes the anode voltage of the diode sensor to fluctuate. Therefore, even if there is no change in the state of the connection part related to the logic ground Vss, there is a possibility that the forward voltage Vf of the diode sensor may vary by several tens of millivolts. On the other hand, in a configuration with multiple connection parts related to the logic ground Vss, the forward voltage Vf of the diode sensor does not vary much even if the connection state of some of the connection parts changes. Therefore, even if the method disclosed in Patent Document 1 is used for a configuration with multiple connection parts related to the logic ground Vss, it is difficult to check the connection state of the multiple connection parts related to the logic ground Vss. Furthermore, if there is a defect in the connection state of the multiple connection parts related to the logic ground Vss, it becomes difficult to accurately measure the temperature of the recording head with the diode sensor, which may lead to a decrease in image quality.

[0005] This disclosure has been made in view of the above points, and aims to enable determination of whether or not the connection status of multiple connections related to the logic ground is normal. [Means for solving the problem]

[0006] One embodiment of the present disclosure is a recording device on which a recording head for discharging liquid can be detachably mounted, wherein the recording head is equipped with a diode and an electronic circuit, the anode of the diode is connected to a constant current source for supplying a constant current to the diode and a voltage detection circuit for detecting the voltage of the anode with reference to the ground of the main body of the recording device, the cathode of the diode and the ground terminal of the electronic circuit can be connected to the ground via each of the number of mounted ground connection parts, and the recording device is equipped with determination means for determining the electrical connection state of the number of mounted ground connection parts based on the voltage of the anode detected by the voltage detection circuit when a constant current is supplied from the constant current source to the ground via the diode and a test current is supplied from the ground terminal of the electronic circuit to the ground. [Effects of the Invention]

[0007] According to this disclosure, it is possible to determine whether the connection status of multiple connections related to the logic ground is normal or not. [Brief explanation of the drawing]

[0008] [Figure 1] Perspective view showing the configuration of the recording device in an embodiment of the present disclosure. [Figure 2] Block diagram showing the system configuration of the recording device in the embodiment of this disclosure. [Figure 3] Perspective view showing the carriage configuration in an embodiment of the present disclosure. [Figure 4] Figure showing the connection part of the recording head in an embodiment of this disclosure. [Figure 5] This figure shows the configuration of a circuit for determining the connection state in an embodiment of the present disclosure. [Figure 6] This figure shows the difference in detection voltage depending on the connection state in the embodiment of this disclosure. [Figure 7] This diagram shows the basic flow of the method for determining the connection status in the embodiments of this disclosure. [Figure 8]Other figures showing the difference in detection voltage depending on the connection state in the embodiments of this disclosure [Figure 9] Figure showing the detected voltage based on the connection state in the embodiment of this disclosure. [Figure 10] Other figures showing the detected voltage based on the connection state in the embodiments of this disclosure [Figure 11] Further figures showing the detected voltage based on the connection state in the embodiments of this disclosure. [Figure 12] Further figures showing the detected voltage based on the connection state in the embodiments of this disclosure. [Figure 13] This figure shows the configuration of other circuits for determining the connection state in the embodiments of this disclosure. [Figure 14] This figure shows the configuration of yet another circuit for determining the connection state in an embodiment of the present disclosure. [Modes for carrying out the invention]

[0009] The embodiments will be described in detail below with reference to the attached drawings. Note that the following embodiments do not limit the disclosures relating to the claims. While the embodiments describe multiple features, not all of these features are essential to the disclosure, and the features may be combined in any way. Furthermore, in the attached drawings, the same or similar configurations are given the same reference numeral, and redundant descriptions may be omitted.

[0010] <First Embodiment> <Overall Structure> Figure 1 is a perspective view showing the configuration of the recording device 100. Figure 1(a) shows the overall appearance, and Figure 1(b) shows the state with the top cover 101 of Figure 1(a) opened, revealing the internal structure.

[0011] The recording device 100 in this embodiment performs recording by applying ink droplets as a recording material from the recording head 102 onto the recording medium 103 by an inkjet recording method. The recording medium 103 is conveyed with the Y direction as the conveyance direction, and a carriage 104 equipped with the recording head 102 reciprocates in the X direction intersecting the Y direction to perform recording. An inkjet recording device including a so-called serial type recording head will be described. However, an inkjet recording device including a so-called line type recording head in which a nozzle row is configured across the recording width of the recording medium 103 may also be used. Further, it may be a multifunctional peripheral device (MFP) in which not only a recording function but also a scanning function, a FAX function, a transmission function, etc. are integrated.

[0012] Subsequently, an input / output unit 105 is provided above the recording device 100. The input / output unit 105 is an operation panel, which displays the remaining ink amount and candidates for the type of the recording medium 103 on the display, and the user can select the type of the recording medium 103 or perform recording settings by operating keys.

[0013] The carriage 104 has an optical sensor 302 described later and a recording head 102 that discharges ink supplied from an ink tank 106. The carriage 104 is configured to be reciprocally movable in the X direction (the moving direction of the carriage 104) along a shaft 108 via a carriage belt 107 by driving a carriage motor (not shown).

[0014] Further, the optical sensor 302 can measure the distance between the recording medium 103 and the carriage 104 by acquiring the diffuse reflection characteristic value and the specular reflection characteristic value on the surface of the recording medium 103.

[0015] The recording medium 103, such as a roll of paper, is transported in the Y direction on a platen 109 by transport rollers (not shown). The platen 109 is provided in a manner corresponding to the scanning area of ​​the carriage 104 and supports the transported recording medium 103 from the back surface. Here, the carriage 104 scans the recording medium 103, which has been transported in the Y direction, in the X direction, and the recording operation is performed by ejecting ink droplets from the recording head 102. When the carriage 104 moves to the edge of the recording area of ​​the recording medium 103, the transport rollers transport a certain amount of the recording medium 103, moving the area for the next recording scan to a position where the recording head 102 can record. By repeating the above operation, an image is recorded.

[0016] In this embodiment, the ink used for image recording is latex ink. When heat is applied to the ink, the water evaporates, the latex resin melts and mixes with the pigment, forming a film on the surface of the recording medium 103 and hardening. Therefore, while a typical water-based inkjet printer requires an ink-receiving layer to catch the ink and prevent bleeding, a latex printer can record even on a recording medium 103 that does not have an ink-receiving layer. In this embodiment, the printed recording medium 103 is transported to the fuser 110, where heat is applied to the recording medium 103, the ink hardens and is fixed on the recording medium 103 (finished state), and then it is discharged from the fuser 110.

[0017] Figure 2 is a block diagram showing the system configuration of the recording device 100 shown in Figure 1.

[0018] The processor 201, such as the CPU, is a control unit that connects to each control block within the recording device 100 and oversees the entire system.

[0019] The communication interface (hereinafter referred to as I / F) 202 is a module that connects the recording device 100 to an external device (not shown) and controls the transmission and reception of signals. The host external device is an information processing device such as a PC (personal computer) or a portable device. Recorded data created by the external device based on image data such as documents and photographs is input to the recording device 100 via the communication I / F 202. The method of communication between the recording device 100 and the external device is not particularly limited, but could be, for example, LAN (Local Area Network), USB (Universal Serial Bus), or the wireless communication standard Wi-Fi (registered trademark).

[0020] Memory 203 is a memory unit composed of storage devices such as ROM (Read Only Memory), RAM (Random Access Memory), and NVRAM (Non-Volatile RAM). Memory 203 may be either volatile or non-volatile memory. For example, it stores programs for controlling the recording device 100 executed by the processor 201, or programs for realizing the operation of this embodiment. Alternatively, it may be used as a buffer section for temporarily storing recording data received by the communication I / F 202. Memory 203 is also used to record information necessary for various controls of the recording device 100, and information that should be retained when the power of the recording device 100 is turned off. Such information may include parameters for adjusting the amount of energy driven by the temperature of the recording head 102, or the results of measuring the amount of ink ejected and consumed from the recording head 102.

[0021] The head control unit 204 is a driver for driving the recording head 102. Synchronized with the position of the recording head 102 detected by the encoder sensor (not shown), it reads recording data from the memory 203 via the processor 201 and outputs it to the recording head 102.

[0022] The motor control unit 205 is a driver for driving various motors 206. These various motors 206 include, for example, a transport motor for transporting the recording medium 103 and a carriage motor for scanning the recording head 102. Other motors 206 include, for example, a supply motor for supplying ink from the ink tank 106 to the recording head 102, and a motor for moving the cap up and down. These motors 206 are composed of stepping motors, DC motors, and the like.

[0023] The sensor control unit 207 is a circuit for controlling various sensors 208. These various sensors 208 include, for example, mechanical sensors for detecting the opening and closing of the upper cover 101, and encoder sensors for detecting the movement of the recording head 102 and the rotation of the transport rollers. Other sensors 208 include, for example, optical sensors for detecting the leading and trailing ends of the transported recording medium 103. It also includes an AD converter 503 that reads an analog signal for detecting the temperature of the recording head 102 from a diode sensor 507 mounted on the recording head 102, which will be described in detail later. The AD converter 503 functions as a voltage detection circuit for detecting the voltage of the anode of the diode sensor 507 on the main body of the recording device 100, with reference to the logic ground Vss.

[0024] <Carriage configuration> Figure 3 shows the configuration of the carriage 104 in this embodiment.

[0025] The carriage 104 is configured with a head holder 301 and is a unit capable of scanning in the width direction of the recording medium 103.

[0026] The head holder 301 is a component that holds the recording head 102, which has an ink ejection port formed on its bottom surface, and the optical sensor 302, which is a reflective sensor directed towards the recording medium 103. A carriage substrate 303 is also contained within the head holder 301 and is configured to be electrically connected to a connection part provided on the back of the recording head 102. The recording head 102 is detachably mounted on the recording device 100.

[0027] Figure 4 shows the connection portion of the recording head 102 in this embodiment.

[0028] The recording head 102 is equipped with multiple terminals for connecting to the head control unit 204 on the main body of the recording device 100, as well as to the power supply, ground, etc. Each of the multiple terminals is composed of a connection pad, and when the recording head 102 is properly mounted on the carriage 104, the connection pads come into contact with pin-shaped connection terminals on the carriage substrate 303, thereby connecting to the main body of the recording device 100. In other words, the connection part is composed of the connection pads and connection terminals.

[0029] As shown in Figure 4, the terminals formed by each connection pad of the recording head 102 are assigned signals as follows: Connection terminal 401a is assigned the heater voltage (VH). There are multiple connection terminals 401a. Connection terminal 402a is assigned the logic voltage (Vdd). Connection terminal 403a is assigned the logic signal. There are multiple connection terminals 403a. Connection terminal 404a is assigned the diode sensor. Connection terminal 409a is assigned the heater voltage ground (HGND). There are multiple connection terminals 409a.

[0030] The logic ground Vss is assigned to connection terminals 405a, 406a, 407a, and 408a. Therefore, the logic ground Vss is assigned to four connection terminals.

[0031] For example, if the contact resistance of each connection terminal (i.e., the contact resistance between the connection pad and the connection pin) is approximately 400 mΩ, then when there are four connections, the combined resistance becomes 1 / 4. In other words, the combined resistance becomes small, approximately 100 mΩ. Therefore, the influence of contact resistance on the circuit can be reduced.

[0032] Similarly, multiple connection pads are used for the heater voltage and the heater voltage ground. Furthermore, since the data bus and logic signals consisting of multiple control signals are each individual signals, multiple connection pads are also required. However, whether these signals are connected at multiple locations or at a single location is not relevant to determining the connection status of the logic ground connection in this embodiment, and therefore no distinction is made.

[0033] <Connection configuration in this embodiment> Figure 5 shows the connection relationships of the control units provided in the recording device 100 and the recording head 102, and also illustrates the configuration of the circuit for determining the connection status of the logic ground connection in this embodiment.

[0034] Each of the connection terminals (connection pads) 401a to 409a of the recording head 102 and each of the connection terminals (connection pins) 401b to 409b provided on the carriage board 303 located on the main body of the recording device 100 are configured to be in a one-to-one pair. Hereafter, paired connection terminals will be described collectively as connection parts.

[0035] First, two power supplies are supplied to the recording head 102 from the head power control unit 501 located in the recording device 100. The head power control unit 501 generates a heater voltage VH used to drive a heater (not shown) for ejecting ink located inside the recording head 102, and a logic voltage Vdd which powers the logic processing unit 504. The heater voltage VH is supplied to the recording head 102 via heater voltage connection units 401a and 401b, and the logic voltage Vdd is supplied via logic voltage connection units 402a and 402b.

[0036] The heater voltage VH is applied to the heater by the heater control unit 505 in the recording head 102 and used as ejection energy to eject ink from the head ejection unit 506.

[0037] A signal containing print information is input to the recording device 100 from an external PC or the like via a communication interface 202. The processor 201 performs calculations based on this signal, and the head control unit 204 adjusts the timing, etc. This generates a logic signal for controlling and driving the recording head 102, which is transmitted to the logic processing unit 504 within the recording head 102. The head control unit 204 is connected to the recording head 102 via logic signal connection units 403a and 403b. Within the recording head 102, the logic processing unit 504 interprets the received logic signal and sends ejection information to the heater control unit 505.

[0038] Here, as mentioned above, the ground of the logic processing unit 504 is configured to be connected to the logic ground Vss of the recording device 100 at multiple points. In other words, the ground terminal of the logic processing unit 504 is connected to the logic ground Vss via four logic ground connection points. The four logic ground connection points are as follows: One is a logic ground connection point composed of terminals 405a and 405b. One is a logic ground connection point composed of terminals 406a and 406b. One is a logic ground connection point composed of terminals 407a and 407b. One is a logic ground connection point composed of terminals 408a and 408b. Therefore, the number of implemented logic ground connection points is four.

[0039] The diode sensor 507 on the recording head 102 is an element for detecting the temperature inside the recording head 102. The temperature inside the recording head 102 is detected using the forward voltage (Vf) characteristics of the diode sensor 507, which is generated based on a predetermined current supplied from the constant current source 502. The current from the constant current source 502 flows into the anode of the diode sensor 507 via the diode sensor signal connection parts 404a and 404b. This current then flows out from the cathode of the diode sensor 507. The current flowing out from the cathode of the diode sensor 507 merges with the current flowing out from the ground terminal of the logic processing unit 504. The merged current then reaches the logic ground Vss of the recording device 100 main body via four logic ground connection parts. However, if some of the four logic ground connection parts are not connected, the number of logic ground connection parts through which the merged current passes will be less than four.

[0040] The current flowing through the heater control unit 505 and the head ejection unit 506 is configured to reach the heater ground HGND of the recording device 100 main body via the heater voltage ground connection units 409a and 409b.

[0041] <Discharge volume control based on recording head temperature> As described above, the recording head 102 converts the heater voltage applied to the heater into energy for ejecting ink. Since the amount of ink ejected by the recording head 102 fluctuates depending on the temperature of the recording head 102, a diode sensor 507 installed inside the recording head 102 measures the temperature as needed and controls the energy required for ink ejection to achieve a stable ejection amount.

[0042] Specifically, the AD converter 503 in the sensor control unit 207 acquires the voltage of the anode of the diode sensor 507 based on temperature. The processor 201 located in the recording device 100 determines the temperature of the recording head 102 based on the anode voltage and controls the head control unit 204 based on that temperature.

[0043] In this embodiment, a 1°C temperature change in the recording head 102 corresponds to a change of approximately 2mV in the anode voltage of the diode sensor 507.

[0044] As mentioned above, the contact resistance per connection point of the recording head 102 (contact resistance between the connection pad and the connection terminal) is approximately 400 mΩ.

[0045] Therefore, if all four logic ground connections are functioning correctly, their combined resistance is 100 mΩ. If three logic ground connections are functioning correctly, their combined resistance is 133 mΩ. If two logic ground connections are functioning correctly, their combined resistance is 200 mΩ. If one logic ground connection is functioning correctly, their combined resistance is 400 mΩ.

[0046] Therefore, using the combined resistance of 100mΩ when all four logic ground connections are functioning correctly as a baseline, the combined resistance increases by 33mΩ when there are three functioning logic ground connections. Using the combined resistance of 100mΩ when all four logic ground connections are functioning correctly as a baseline, the combined resistance increases by 100mΩ when there are two functioning logic ground connections. Using the combined resistance of 100mΩ when all four logic ground connections are functioning correctly as a baseline, the combined resistance increases by 300mΩ when there is one functioning logic ground connection.

[0047] Furthermore, the logic current is typically around 150mA. Therefore, if all four logic ground connections are functioning correctly, a voltage of 15mV will be generated across the logic ground connections. If three logic ground connections are functioning correctly, a voltage of 20mV will be generated across the logic ground connections. If two logic ground connections are functioning correctly, a voltage of 30mV will be generated across the logic ground connections. If one logic ground connection is functioning correctly, a voltage of 60mV will be generated across the logic ground connections.

[0048] Therefore, using the 15mV voltage when all four logic ground connections are functioning correctly as a baseline, the voltage increases by 5mV when there are three functioning logic ground connections. Using the 15mV voltage when all four logic ground connections are functioning correctly as a baseline, the voltage increases by 15mV when there are two functioning logic ground connections. Using the 15mV voltage when all four logic ground connections are functioning correctly as a baseline, the voltage increases by 45mV when there is one functioning logic ground connection.

[0049] As mentioned above, a 1°C temperature change in the recording head 102 corresponds to an approximately 2mV change in the anode voltage of the diode sensor 507. Therefore, when the voltage increases of 5mV, 15mV, and 45mV are converted to temperature changes of 2.5°C, 7.5°C, and 22.5°C, respectively. In other words, if one of the four logic ground connections becomes faulty, the detected temperature will increase by 2.5°C. If two of the four logic ground connections become faulty, the detected temperature will increase by 7.5°C. If three of the four logic ground connections become faulty, the detected temperature will increase by 22.5°C.

[0050] In order to achieve high-precision printing, it is necessary to change the energy required for ink ejection for every approximately 2°C temperature change. Therefore, a 2.5°C temperature change leads to fluctuations in the amount of ink ejected, which can cause a decrease in image quality. In other words, even a single faulty logic ground connection can result in a decrease in image quality.

[0051] Furthermore, the forward voltage Vf of the diode sensor 507 itself exhibits variations of up to several tens of millivolts for the same temperature. Therefore, simply reading the anode voltage of the diode sensor 507 makes it difficult to determine whether the problem is due to a faulty connection in the logic ground connection or variations in the characteristics of the diode sensor 507.

[0052] <Configuration for determining the connection status of the logic ground connection in this embodiment> This embodiment aims to improve the accuracy of temperature detection, which is a factor in image quality degradation, by determining the connection status of logic ground connections, particularly in a configuration having multiple logic ground connections.

[0053] To detect the temperature of the recording head 102, a predetermined constant current (denoted as Ix) is supplied from the constant current source 502 to the diode sensor 507, creating a forward voltage Vf between the anode and cathode of the diode sensor 507.

[0054] Furthermore, the head control unit 204 controls the logic processing unit 504 so that the test current flowing through the logic processing unit 504 is a predetermined value (let's call it A1). Here, the current flowing through the logic processing unit 504 is the current that flows from the logic processing unit 504 to the logic ground Vss via the ground terminal and logic ground connection part of the logic processing unit 504. In addition to this, the logic processing unit 504 also has an input terminal, an output terminal, and power supply terminals connected to the logic voltage connection parts 402a and 402b. If the current flowing through the input terminal and output terminal can be ignored, then the current flowing through the logic processing unit 504 is equal to the current flowing into the power supply terminals via the logic voltage connection parts 402a and 402b.

[0055] For example, the current flowing through the logic processing unit 504 can be adjusted by providing a circuit within the logic processing unit 504 that can change the current consumption. Such a circuit may be related to heater control, or it may be unrelated to heater control. In other words, such a circuit may or may not be provided solely for the purpose of current adjustment.

[0056] Then, the voltage at the anode of the diode sensor 507 in this state is acquired by the AD converter 503. This voltage is denoted as Vadc1.

[0057] This voltage Vadc1 has the value obtained by adding the forward voltage Vf and the voltage Vg between both terminals of the logic ground connection.

[0058] Vadc1 = Vf + Vg ... (1) Here, a constant current Ix and a test current A1 flow through the logic ground connection, so the voltage Vg between the two terminals of the logic ground connection can be divided into the voltage due to the constant current Ix and the voltage due to the test current A1. Here, the voltage between the two terminals of the logic ground connection due to the constant current Ix is represented by Vx, and the voltage between the two terminals of the logic ground connection due to the test current A1 is represented by V1. Also, the contact resistance between the two terminals of one logic ground connection is represented by Rs. Furthermore, let n be the number of logic ground connections that are in a normal connection state. Then, the voltage Vg can be expressed as follows.

[0059] Vg = Vx + V1 =Ix×Rs / n+A1×Rs / n ···(2) From equations (1) and (2) above, Vadc1 =Vf+Vx+V1 =Vf+Ix×Rs / n+A1×Rs / n (3) You can obtain this.

[0060] Next, the head control unit 204 controls the logic processing unit 504 so that the test current flowing through the logic processing unit 504 becomes a predetermined value (let's call it A2). The constant current flowing through the diode sensor 507 is not changed, and there is no temperature change. Therefore, the general formula for diode current is... I x =I0×(exp(qVf / kT)-1) ···(4) As is clear from this, Vf does not change. Here, V2 represents the voltage between the two terminals of the logic ground connection due to the test current A2. Then, the anode voltage in this case, Vadc2, can be expressed as follows.

[0061] Vadc2 =Vf+Vx+V2 =Vf+Ix×Rs / n+A2×Rs / n (5) Subtracting equation (3) from equation (5) above, ΔVadc =Vadc2-Vadc1 =V2-V1 =(A2-A1)×Rs / n ···(6) We can obtain the following. Since ΔVadc is a function of n, we can obtain the following equation from equation (6) above.

[0062] ΔVadc(n) =(A2-A1)×Rs / n ···(7) If the number of logic ground connections n is 1, ΔVadc(1) =(A2-A1)×Rs ···(8) Therefore, if the number of logic ground connections n is 2, ΔVadc(2) =(A2-A1)×Rs / 2 ···(9) Therefore, if the number of logic ground connections n is 3, ΔVadc(3) =(A2-A1)×Rs / 3 ···(10) Therefore, if the number of logic ground connections n is 4, ΔVadc(4) =(A2-A1)×Rs / 4 ···(11) Furthermore, using the case where the number of logic ground connections n is 4 as a baseline, ΔVadc(n) =ΔVadc(4)×(4 / n) ···(12) Therefore, ΔVadc increases as the number of logic ground connections with a normal connection state n decreases. In other words, the difference ΔVadc(n) between the voltage when the current flowing through the logic processing unit 504 is A1 and the voltage when the current flowing through the logic processing unit 504 is A2 increases as the number of logic ground connections with a normal connection state n decreases.

[0063] More specifically, the difference ΔVadc(n) is 4 / 3 times greater when the number of logic ground connections n that are in a normal state is 3 compared to when the number n is 4.

[0064] ΔVadc(3) =ΔVadc(4)×(4 / 3) ···(13) In other words, the difference ΔVadc(n) is 4 / 3 times greater when the number of logic ground connections with abnormal connection status (Nn) is 1 compared to when that number (Nn) is 0. Here, N is the total number of logic ground connections.

[0065] The difference ΔVadc(n) is 4 / 2 times = 2 times greater when the number of logic ground connections n that are in a normal state is 2, compared to when the number n is 4.

[0066] ΔVadc(2) =ΔVadc(4)×(4 / 2)=ΔVadc(4)×2 ···(14) In other words, the difference ΔVadc(n) is twice as large when the number of logic ground connections (Nn) that are not functioning correctly is 2 compared to when that number (Nn) is 0.

[0067] The difference ΔVadc(n) is four times greater when the number of logic ground connections with a normal connection state n is 1 compared to when the number n is 4.

[0068] ΔVadc(3) =ΔVadc(4)×(4 / 1)=ΔVadc(4)×4 ···(15) In other words, the difference ΔVadc(n) is four times greater when the number of logic ground connections (Nn) that are not functioning correctly is 3 compared to when that number (Nn) is 0.

[0069] Figure 6(a) shows a graph illustrating the above relationship.

[0070] As shown in Figure 6(b), the threshold is set between ΔVadc(4) and ΔVadc(3). In this way, if the measured ΔVadc is below this threshold, it can be confirmed that the connection status of all four logic ground connections is normal. Conversely, if the measured ΔVadc is above this threshold, it can be confirmed that the connection status of at least one of the four logic ground connections is abnormal.

[0071] Although not shown in the diagram, a first threshold may be set between ΔVadc(4) and ΔVadc(3), a second threshold between ΔVadc(3) and ΔVadc(2), and a third threshold between ΔVadc(2) and ΔVadc(1). By doing so, the number of logic ground connections with normal connection status can be confirmed by comparing the measured ΔVadc with these three thresholds.

[0072] These thresholds can be set, for example, during the manufacturing of the recording device 100 and stored in a storage unit such as the memory 203.

[0073] The threshold value may be changed to a different value within a range where the temperature error of the recording head 102 detected by the diode sensor 507 does not lead to a decrease in image quality.

[0074] <Method for determining the connection status of the logic ground connection in this embodiment> Figure 7 is a flowchart illustrating the method for determining the connection status of the logic ground connection in this embodiment.

[0075] The recording head 102 is replaced by operating the input / output unit 105 to switch the recording device 100 into head replacement mode. The user follows the head replacement procedure displayed on the control panel's display, opens the top cover 101, removes the old recording head 102 from the head holder 301 if it is installed, and then installs the new recording head 102. After that, when the top cover 101 is closed, the main body of the recording device 100 detects this and starts the identification process.

[0076] First, in step S701, the processor 201 uses the constant current source 502 to supply a predetermined current to the diode sensor 507. Then, the processor 201 reads the anode voltage of the diode sensor 507 using the AD converter 503. The predetermined current supplied to the diode sensor 507 in step S701 may be test current A1 or test current A2, but it may also be a current with other values.

[0077] Next, in S702, the processor 201 performs an initial determination of the voltage read in S701. If the anode voltage obtained using the AD converter 503 is close to the forward voltage Vf (usually about 0.8V) of the diode sensor 507, the process proceeds to the next step, S703. However, if the read anode voltage is Vdd (usually about 3.3V), it is presumed that the connection state of the diode sensor signal connection parts 404a and 404b is poor. Alternatively, in that case, it is presumed that the connection state of all four logic ground connection parts is poor. In either case, it is presumed that the diode sensor 507 is in a non-conductive state. Therefore, in that case, the processor 201 determines that there is a connection problem and proceeds to S709. Here, the four logic ground connection parts are the logic ground connection parts (405a, 405b), (406a, 406b), (407a, 407b), and (408a, 408b). The same applies below.

[0078] In S703, the processor 201 sends a control signal to the logic processing unit 504 in the recording head 102 via the head control unit 204 in the recording device 100. This control signal causes a predetermined test current A1 to flow out from the ground terminal of the logic processing unit 504.

[0079] Next, in S704, the processor 201 acquires the anode voltage Vadc1 of the diode sensor 507 using the AD converter 503, while the constant current source 502 is supplying a predetermined constant current Ix to the diode sensor 507.

[0080] In S705, the processor 201 sends a control signal to the logic processing unit 504 in the recording head 102 via the head control unit 204 in the recording device 100. This control signal causes a predetermined test current A2, which is greater than the test current A1, to flow out from the ground terminal of the logic processing unit 504.

[0081] Next, in S706, the processor 201 acquires the anode voltage Vadc2 of the diode sensor 507 using the AD converter 503, while the constant current source 502 is supplying a predetermined constant current Ix to the diode sensor 507.

[0082] Next, in S707, the processor 201 obtains the differential voltage ΔVadc by subtracting the anode voltage Vadc1 obtained in S704 from the anode voltage Vadc2 obtained in S706. Then, the processor 201 evaluates the differential voltage ΔVadc. In other words, the processor 201 compares the differential voltage ΔVadc measured with the four logic ground connections in a normal state with the differential voltage ΔVadc obtained in S707.

[0083] Next, in S708, if the two differential voltages ΔVadc are approximately equal when compared in S707, the processor 201 determines that the connection status of the four logic ground connections is normal and terminates the determination method.

[0084] On the other hand, if the differential voltage ΔVadc obtained in S707 is larger than the differential voltage ΔVadc obtained in advance, the processor 201 determines that the connection state of at least one of the four logic ground connections is abnormal and proceeds to processing in S709. An abnormal connection state means, for example, that there is a poor contact.

[0085] In S709, the processor 201 outputs a warning message from the input / output unit 105 indicating that there is a suspected poor contact in one of the four logic ground connections. The processor 201 also outputs a warning message from the input / output unit 105 prompting the removal and reinsertion of the recording head 102. Then, the processor 201 terminates the detection process. The output of the warning message may be a display of characters, symbols, or codes, an audio output of the warning message, or a combination of these.

[0086] As described above, in the above embodiment, in addition to the forward current flowing through the diode sensor 507, two different currents are flowed through the four logic ground connections twice, and the difference is detected. This allows for the detection of a differential voltage proportional to the contact resistance of the logic ground connections, without being affected by the diode sensor 507, which includes variations in its characteristics. By comparing this with the differential voltage when the connection state of the logic ground connections is normal, it is possible to determine whether the connection state of the logic ground connections is normal or not.

[0087] This allows us to confirm that the connection status of the logic ground connection is normal, thereby ensuring the accuracy of temperature detection of the recording head 102 by the diode sensor 507.

[0088] <Second Embodiment> In the above embodiment, a method was described in which the logic processing unit 504 is controlled to generate predetermined test currents A1 and A2, and a voltage proportional to the magnitude of the contact resistance is detected. Alternatively, the logic processing unit 504 may be configured to interrupt the current, thereby setting the test current A1 to zero and performing the above-described discrimination method.

[0089] In equation (5) above, if we set A1=0, ΔVadc =V2 =A2 × Rs / n ···(16) In this case, as shown in the above equation, V1 (=A2×Rs / n), which is generated depending on the test current A1 and the contact resistance value, becomes zero, so ΔVadc is expressed only by V2. The voltage Vx (=Ix×Rs / n) generated at the logic ground connection point due to the forward voltage Vf of the diode sensor 507, which includes variations, and the constant current Ix flowing through the diode sensor 507 is removed from ΔVadc. Therefore, the connection state of the logic ground connection point can be determined based on the value of voltage V2.

[0090] Here, the discrimination method described using Figure 7 can be applied to the second embodiment.

[0091] In the second embodiment, in S703, the test current A1 is set to zero. Even in this case, a predetermined constant current Ix is supplied to the diode sensor 507. Therefore, the anode voltage Vadc1 of the diode sensor 507 read in S704 is, Vadc1 = Vf + Ix × Rs / n ... (17) It can be expressed as follows.

[0092] S705 and S706 are carried out in the same manner as in the first embodiment. The anode voltage Vadc2 of the diode sensor 507 read in S706 can be expressed by equation (5) above.

[0093] Therefore, the voltage difference ΔVadc obtained in S707 can be expressed by equation (16) above.

[0094] Figure 8 shows Vadc1(n), Vadc2(n), and ΔVadc(n) for n=1 to 4 when A1=0.

[0095] <Third Embodiment> In the above embodiment, the currents of predetermined values ​​generated by controlling the logic processing unit 504 were described as A1 and A2. However, for example, the logic processing unit 504 may be configured and controlled so that A1 is 200mA and A2 is 300mA. In this case, if the potential difference ΔVadc can be detected, the value of the contact resistance (let's call it R) can be determined by the following formula.

[0096] ΔVadc =V2-V1 =(A2×R)-(A1-R)=(A2-A1)×R ···(18) Therefore, R = ΔVadc / (A2 - A1) ... (19) In this case, for example, if the value of ΔVadc is detected as 10mV, the contact resistance can be calculated as 100mΩ. In this embodiment, the contact resistance of each connection terminal is assumed to be approximately 400mΩ, so this result indicates that all four connections of the logic ground connection are properly connected. If the contact resistance value were 133mΩ, it would be estimated that one of the connections of the logic ground connection is faulty, and the user can be notified of the faulty connection and prompted to reattach the recording head 102.

[0097] Furthermore, the value of the contact resistance R can be calculated. By using the calculated value of the contact resistance R to correct the temperature information obtained from the diode sensor 507, it is possible to print on the recording device 100 without degrading image quality, without notifying the user of a connection problem or prompting them to reattach the recording head 102.

[0098] In other words, if there is no current flowing from the ground terminal of the logic processing unit 504 to the logic ground Vss, the anode voltage Vadc of the diode sensor 507 will be: Vadc = Vf + Ix × R ... (20) However, if we transform this, Vf = Vadc - Ix × R ... (21) This can be obtained. Here, since Vadc can be measured directly by the AD converter 503, if the contact resistance R is known, the forward voltage Vf can be determined using equation (21) above. Then, based on equation (4) above, the forward voltage Vf and the constant current Ix, the temperature T of the recording head 102 can be obtained, and correction can be made based on this.

[0099] <Fourth Embodiment> In the above embodiment, the following method may be used as a control method for generating test currents A1 and A2 in the logic processing unit 504. That is, the processor 201 may process predetermined image data stored in the memory 203 and transmit it to the logic processing unit 504 via the head control unit 204 as print information. At this time, based on the print information, ejection information is sent from the logic processing unit 504 to the heater control unit 505 within the recording head 201 and ink is ejected from the head ejection unit 506. The ink may be ejected onto the recording medium 103, or it may be ejected onto an absorber that absorbs the ejected ink during maintenance. Here, the memory 203 is prepared with two types of image data: data that places a light processing load on the logic processing unit 504 and consumes little current, and data that places a relatively heavy processing load on the logic processing unit 504 and consumes a large amount of current. By doing this, a difference between test currents A1 and A2 can be generated. Furthermore, by measuring the values ​​of the test currents A1 and A2 that flow when this image data is processed, such as at the time of factory shipment, it becomes possible to calculate the contact resistance value of the logic ground connection.

[0100] <Fifth Embodiment> The fifth embodiment determines the current-voltage characteristics corresponding to the number of logic ground connections that are in a normal connection state.

[0101] As shown in Figure 9(a), after confirming that the connection status of all (four in the example shown) logic ground connections is normal, measure the voltage Vp1 when test current A1 is applied and the voltage Vp2 when test current A2 is applied.

[0102] As shown in Figure 9(b), the relationship between Vadc and Iy is based on the pairs (A1, Vp1) and (A2, Vp2). Vadc =Vf+Ix×Rs / 4+Iy×Rs / 4 The coefficient in Vf+Ix×Rs / 4 Rs / 4 We calculate the following: Here, Vadc is the voltage at the anode of the diode sensor 507, and Iy is the current flowing from the ground terminal of the logic processing unit 504 to the logic ground Vss.

[0103] As shown in Figure 9(c), the method described with reference to Figures 9(a) and 9(b) is repeated for the cases where the number of logic ground connections n in a normal connection state is 3, 2, and 1.

[0104] This allows us to determine the characteristics of current Iy versus voltage Vadc based on the number of logic grounds with a normal connection status.

[0105] Furthermore, based on the current-voltage characteristics when four logic ground connections are functioning correctly, the current-voltage characteristics when all n logic ground connections are functioning correctly can be determined. In other words, generally, this characteristic can be expressed as follows: Vadc(n)=Vf+Ix (Rs / n)+Iy(Rs / n) (22) It can be expressed as follows. If the coefficients are expressed in terms of αn and βn, Vadc(n)=αn+βn·Iy···(23) Here, αn = Vf + Ix·(Rs / n) βn = Rs / n This is the result. If all four logic ground connections are functioning correctly, Vadc(n) = α₄ + β₄·Iy This is the result. Then, the values ​​of α4 and β4 can be determined from the measurements taken when the four logic ground connections are functioning correctly. Expressing αn and βn using α4 and β4, αn = α⁴ + (4 / n-1)·Ix·β⁴ βn = (4 / n)·β4 This is because the value of Ix is measurable, so if we can determine α4 and β4, we can calculate the values ​​of αn and βn. In other words, as described above, based on the current-voltage characteristics when all four logic ground connections are functioning correctly, we can determine the current-voltage characteristics when n logic ground connections are functioning correctly.

[0106] <Sixth Embodiment> The sixth embodiment determines the number of logic ground connections that are in a normal connection state by using the four characteristics obtained in the fifth embodiment and one measurement.

[0107] A constant current Ix is applied to the diode sensor 507, and a test current A2 is applied from the ground terminal of the logic processing unit 504 to the logic ground Vss. The anode voltage Vadc of the diode sensor 507 at this time is then measured. It is then determined which of the four characteristic lines (A2, Vadc) is closest to, and based on the closest characteristic, the number of logic ground connections that are in a normal state is determined. Figure 10(a) shows an example where (A2, Vadc) is closest to the characteristic line when the number of logic ground connections that are in a normal state is 2.

[0108] As shown in Figure 10(b), multiple measurements may be taken and the average values ​​of these measurements compared with the characteristic line.

[0109] <Seventh Embodiment> The seventh embodiment determines the number of logic ground connections that are in a normal connection state based on the four characteristics and two measurements obtained in the fifth embodiment.

[0110] A constant current Ix is applied to the diode sensor 507, and a test current A1 is applied from the ground terminal of the logic processing unit 504 to the logic ground Vss. The anode voltage Vadc1 of the diode sensor 507 at this time is then measured. A constant current Ix is also applied to the diode sensor 507, and a test current A2 is applied from the ground terminal of the logic processing unit 504 to the logic ground Vss. The anode voltage Vadc2 of the diode sensor 507 at this time is then measured.

[0111] Then, it is determined which of the four characteristic lines (A1, Vadc1) and (A2, Vadc2) are closest to, and based on the closest characteristic, the number of logic ground connections with a normal connection state is determined. Figure 11(a) shows an example where (A1, Vadc1) and (A2, Vadc2) are closest to the characteristic line when the number of logic ground connections with a normal connection state is 2.

[0112] As shown in Figure 11(b), multiple measurements may be taken for each test current A1 and A2, and the average values ​​of these measurements may be compared with the characteristic curves.

[0113] <Eighth Embodiment> The eighth embodiment determines the number of logic ground connections that are in a normal connection state based on the four characteristics and three measurements obtained in the fifth embodiment.

[0114] A constant current Ix is applied to the diode sensor 507, and a test current A1 is applied from the ground terminal of the logic processing unit 504 to the logic ground Vss. The anode voltage Vadc1 of the diode sensor 507 at this time is measured. A constant current Ix is applied to the diode sensor 507, and a test current A2 is applied from the ground terminal of the logic processing unit 504 to the logic ground Vss. The anode voltage Vadc2 of the diode sensor 507 at this time is measured. Furthermore, a constant current Ix is applied to the diode sensor 507, and a current A3 is applied from the ground terminal of the logic processing unit 504 to the logic ground Vss. The anode voltage Vadc3 of the diode sensor 507 at this time is measured.

[0115] Then, it is determined which of the four characteristic lines (A1, Vadc1), (A2, Vadc2), and (A3, Vadc3) are closest to, and based on the closest characteristic, the number of logic ground connections with a normal connection state is determined. Figure 12(a) shows an example where (A1, Vadc1), (A2, Vadc2), and (A3, Vadc3) are closest to the characteristic line when the number of logic ground connections with a normal connection state is 2.

[0116] Although not shown in the diagram, multiple measurements may be taken for each test current A1, A2, and A3, and the average values ​​of these measurements may be compared with the characteristic curves.

[0117] <Ninth Embodiment> The ninth embodiment determines the number of logic ground connections that are in a normal connection state by using the four characteristics obtained in the fifth embodiment and by measuring m multiple times.

[0118] A constant current Ix is applied to the diode sensor 507, and a current Ai is applied from the ground terminal of the logic processing unit 504 to the logic ground Vss. The anode voltage Vadci of the diode sensor 507 at this time is then measured. This process is repeated multiple times.

[0119] Then, it is determined which of the four characteristics the line from (A1, Vadc1) to (Am, Vadcm) is closest to, and the number of logic ground connections that are in a normal state is determined based on the closest characteristic. The determination is made, for example, as follows: A line representing the characteristic is found from (A1, Vadc1) to (Am, Vadcm) using the least squares method. Then, the characteristic with the slope closest to the slope of the found line is selected from the fourth characteristic found in the fifth embodiment. Figure 12(b) shows an example that is closest to the characteristic line when the number of logic ground connections that are in a normal state is 2, from (A1, Vadc1) to (Am, Vadcm).

[0120] As shown in Figure 13, an ammeter 1201 for measuring the current flowing into the logic processing unit 504 may be inserted between the head power control unit 501 and the logic processing unit 504. The current measured by the ammeter 1201 may be considered as the current flowing from the ground terminal of the logic processing unit 504 to the logic ground VSS. Multiple pairs of current measured by the ammeter 1201 and the voltage at the anode of the diode sensor 507 may be prepared, and a linear line showing the characteristics may be obtained using the least squares method based on these pairs.

[0121] <Tenth Embodiment> In the above embodiment, the constant current source 502 and the AD converter 503 are located in the main body of the recording device 100. However, this is not limited to this configuration, and as shown in Figure 14, the constant current source 502 and the AD converter 503 may be located on the recording head 102.

[0122] <Other Embodiments> A computer connected to the recording device 100 may perform the determination method.

[0123] In the above embodiment, the case where the logic ground connection is connected at four points was explained as an example, but the above determination of the connection state and calculation of the contact resistance value are also possible when the logic ground connection has one, two, three, five or more connection points.

[0124] The logic processing unit 504 may be replaced with other electronic circuits as long as the current flowing out from the ground terminal can be adjusted.

[0125] The recording device 100 in this embodiment may perform recording by applying droplets of liquid other than ink from the recording head 102 onto the recording medium 103 using an inkjet recording method.

[0126] Embodiments of the present disclosure may also be implemented by a computer in a system or device that includes one or more circuits (e.g., application-specific integrated circuits (ASICs)) for performing one or more functions of the embodiments described above, which are recorded on a storage medium (which may be more entirely referred to as a “non-temporary computer-readable storage medium”), and / or for performing one or more functions of the embodiments described above, and or by being implemented by a computer in a system or device that includes one or more circuits (e.g., application-specific integrated circuits (ASICs)) for performing one or more functions of the embodiments described above, which are recorded on a storage medium. The computer may comprise one or more processors (e.g., a central processing unit (CPU), a microprocessing unit (MPU)), and may include separate computers or a network of separate processors for reading and executing computer-executable instructions. Computer-executable instructions may be provided to the computer from, for example, a network or a storage medium. The storage medium may include, for example, one or more of the following: hard disks, random access memory (RAM), read-only memory (ROM), storage for distributed computing systems, optical discs (Compact Discs (CDs), Digital Multipurpose Discs (DVDs), or Blu-ray Discs (BDs) (registered trademarks)), flash memory devices, and memory cards.

[0127] <Technical Features of This Disclosure> This disclosure includes the following configurations, methods, and programs.

[0128] [Configuration 1] A recording device in which a recording head for dispensing liquid can be detachably mounted, The recording head is equipped with a diode and an electronic circuit, the anode of the diode is connected to a constant current source for supplying a constant current to the diode and a voltage detection circuit for detecting the voltage of the anode relative to the ground of the recording device body, the cathode of the diode and the ground terminal of the electronic circuit can be connected to the ground via each of the number of ground connection points mounted. The recording device is The system includes a determination means for determining the electrical connection state of the ground connection portion of the number of mounted components based on the voltage of the anode detected by the voltage detection circuit when a constant current is passed from the constant current source to the ground via the diode, and a test current is passed from the ground terminal of the electronic circuit to the ground. Recording device.

[0129] [Configuration 2] The determination means is A first means for causing a voltage detection circuit to detect a first voltage at the anode when a constant current is passed from the constant current source to the ground via the diode, and a first test current is passed from the ground terminal of the electronic circuit to the ground, A second means for causing the voltage detection circuit to detect a second voltage at the anode when a constant current is passed from the constant current source to the ground via the diode, and a second test current is passed from the ground terminal of the electronic circuit to the ground, A third means for determining the electrical connection state of the ground connection portion of the number of mounted components based on the first voltage and the second voltage, Equipped with, The recording device described in Configuration 1.

[0130] [Configuration 3] The aforementioned connection state is whether the number of electrically connected ground connection parts among the number of implemented ground connection parts is equal to the number of implemented parts. The third means determines whether the number of connected ground connections is equal to the number of implemented components, based on the difference between the first voltage detected by the first means and the second voltage detected by the second means, and the difference between the first voltage and the second voltage when the number of electrically connected ground connections is equal to the number of implemented components. The recording device described in Configuration 2.

[0131] [Structure 4] The aforementioned connection state refers to the number of electrically connected ground connection parts among the number of implemented ground connection parts, The third means determines the number of electrically connected ground connections based on the difference between the first voltage detected by the first means and the second voltage detected by the second means, and the difference between the first voltage and the second voltage corresponding to the number of electrically connected ground connections. The recording device described in Configuration 2.

[0132] [Composition 5] The determination means is A fourth means for causing the voltage detection circuit to detect a third voltage at the anode when a constant current is passed from the constant current source to the ground via the diode, and a third test current is passed from the ground terminal of the electronic circuit to the ground, A fifth means for causing the voltage detection circuit to detect a fourth voltage at the anode when a constant current is supplied from the constant current source to the ground via the diode, and no test current is supplied from the ground terminal of the electronic circuit to the ground; A sixth means for determining the electrical connection state of the ground connection portion of the number of mounted components based on the third voltage and the fourth voltage, Equipped with, The recording device described in Configuration 1.

[0133] [Composition 6] The aforementioned connection state is whether the number of electrically connected ground connection parts among the number of implemented ground connection parts is equal to the number of implemented parts. The sixth means determines whether the number of connected ground connections is equal to the number of implemented units, based on the difference between the third voltage detected by the fourth means and the fourth voltage detected by the fifth means, and the difference between the third voltage and the fourth voltage when the number of electrically connected ground connections is equal to the number of implemented units. The recording device described in Configuration 5.

[0134] [Composition 7] The aforementioned connection state refers to the number of electrically connected ground connection parts among the number of implemented ground connection parts, The sixth means determines the number of electrically connected ground connections based on the difference between the third voltage detected by the fourth means and the fourth voltage detected by the fifth means, and the difference between the third voltage and the fourth voltage corresponding to the number of electrically connected ground connections. The recording device described in Configuration 5.

[0135] [Structure 8] The determination means is A seventh means for causing the voltage detection circuit to detect the fifth voltage at the anode when a constant current is passed from the constant current source to the ground via the diode, and a fourth test current is passed from the ground terminal of the electronic circuit to the ground, An eighth means for determining the electrical connection state of the ground connection portion of the number of mounted components based on the fifth voltage, Equipped with, The recording device described in Configuration 1.

[0136] [Composition 9] The aforementioned connection state is whether the number of electrically connected ground connection parts among the number of implemented ground connection parts is equal to the number of implemented parts. The eighth means determines whether the number of connected ground connections is equal to the number of implemented units, based on the fifth voltage detected by the seventh means and the fifth voltage when the number of electrically connected ground connections is equal to the number of implemented units. The recording device described in configuration 8.

[0137] [Configuration 10] The aforementioned connection state refers to the number of electrically connected ground connection parts among the number of implemented ground connection parts, The eighth means determines the number of electrically connected ground connections based on the fifth voltage detected by the seventh means and the fifth voltage corresponding to the number of electrically connected ground connections. The recording device described in configuration 8.

[0138] [Composition 11] The determination means is A means for repeatedly passing a constant current from the constant current source to the ground via the diode, and detecting the voltage at the anode when a test current is passed from the ground terminal of the electronic circuit to the ground using the voltage detection circuit, for a plurality of test currents, A means for determining the electrical connection state of the ground connection portion of the number of implemented units based on the plurality of test currents and the voltages of the plurality of anodes corresponding to the plurality of test currents, Equipped with, The recording device described in Configuration 1.

[0139] [Composition 12] The aforementioned connection state is whether the number of electrically connected ground connections among the number of implemented ground connections is equal to the number of implemented ground connections. A recording device as described in any one of configurations 1 to 11.

[0140] [Composition 13] The aforementioned connection state refers to the number of electrically connected ground connection parts among the number of implemented ground connection parts. A recording device as described in any one of configurations 1 to 11.

[0141] [Composition 14] The system further includes means for outputting a warning if the connection status of at least some of the ground connections among the aforementioned number of implemented ground connections is not normal. A recording device as described in any one of configurations 1 to 13.

[0142] [Composition 15] The system further includes a temperature detection means for detecting the temperature of the recording head based on the voltage of the anode. A recording device as described in any one of configurations 1 to 14.

[0143] [Composition 16] The temperature detection means includes means for correcting the detected temperature based on the connection state. The recording device described in configuration 15.

[0144] [Composition 17] The determination means is Even if control is performed to supply a constant current from the constant current source to the ground via the diode, if the voltage of the anode detected by the voltage detection circuit is the voltage when the diode is in a non-conducting state, it is determined that there is no electrically connected ground connection among the number of ground connections, or that the anode of the diode is not connected to the constant current source and the voltage detection circuit. A recording device according to any one of configurations 1 to 16.

[0145] [Composition 18] The determination means further comprises means for outputting a warning if it determines that there are no electrically connected ground connections among the number of ground connections, or that the anode of the diode is not connected to the constant current source and the voltage detection circuit. The recording device described in configuration 17.

[0146] [Composition 19] The constant current source and the voltage detection circuit are further comprising: A recording device as described in any one of configurations 1 to 18.

[0147] [Configuration 20] The recording head further comprises the aforementioned recording head, A recording device as described in any one of configurations 1 to 19.

[0148] [Composition 21] The recording head is equipped with the constant current source and the voltage detection circuit. The recording device described in configuration 20.

[0149] [method] A method for determining the connection status between a recording head that ejects liquid and a recording device on which the recording head is detachably mounted, The recording head is equipped with a diode and an electronic circuit, the anode of the diode is connected to a constant current source for supplying a constant current to the diode and a voltage detection circuit for detecting the voltage of the anode relative to the ground of the recording device body, the cathode of the diode and the ground terminal of the electronic circuit can be connected to the ground via each of the number of ground connection points mounted. The aforementioned determination method is, A determination step in which a constant current is passed from the constant current source to the ground via the diode, and a test current is passed from the ground terminal of the electronic circuit to the ground, and the electrical connection state of the ground connection portion of the number of mounted units is determined based on the voltage of the anode detected by the voltage detection circuit. A method for determining the thumbnail.

[0150] [Program 1] A program for causing a computer mounted on a recording device or a computer connected to a recording device to execute a determination method for determining the connection status between a recording head that ejects liquid and a recording device on which the recording head is detachably mounted, The recording head is equipped with a diode and an electronic circuit, the anode of the diode is connected to a constant current source for supplying a constant current to the diode and a voltage detection circuit for detecting the voltage of the anode relative to the ground of the recording device body, the cathode of the diode and the ground terminal of the electronic circuit can be connected to the ground via each of the number of ground connection points mounted. The program is installed on the computer. A determination step in which a constant current is passed from the constant current source to the ground via the diode, and a test current is passed from the ground terminal of the electronic circuit to the ground, and the electrical connection state of the ground connection portion of the number of mounted units is determined based on the voltage of the anode detected by the voltage detection circuit. A program that executes the command.

[0151] [Program 2] A program for causing a recording device to execute a determination method for determining the connection status between a recording head that ejects liquid and a recording device on which the recording head is detachably mounted, The recording head is equipped with a diode and an electronic circuit, the anode of the diode is connected to a constant current source for supplying a constant current to the diode and a voltage detection circuit for detecting the voltage of the anode relative to the ground of the recording device body, the cathode of the diode and the ground terminal of the electronic circuit can be connected to the ground via each of the number of ground connection points mounted. The program is recorded in the recording device. A determination step in which a constant current is passed from the constant current source to the ground via the diode, and a test current is passed from the ground terminal of the electronic circuit to the ground, and the electrical connection state of the ground connection portion of the number of mounted units is determined based on the voltage of the anode detected by the voltage detection circuit. To execute program.

Claims

1. A recording device in which a recording head for dispensing liquid can be detachably mounted, The recording head is equipped with a diode and an electronic circuit, the anode of the diode is connected to a constant current source for supplying a constant current to the diode and a voltage detection circuit for detecting the voltage of the anode relative to the ground of the recording device body, the cathode of the diode and the ground terminal of the electronic circuit can be connected to the ground via each of the number of ground connection points mounted. The recording device is The system includes a determination means for determining the electrical connection state of the ground connection portion of the number of mounted components based on the voltage of the anode detected by the voltage detection circuit when a constant current is passed from the constant current source to the ground via the diode, and a test current is passed from the ground terminal of the electronic circuit to the ground. Recording device.

2. The determination means is A first means for causing the voltage detection circuit to detect a first voltage at the anode when a constant current is passed from the constant current source to the ground via the diode, and a first test current is passed from the ground terminal of the electronic circuit to the ground, A second means for causing the voltage detection circuit to detect a second voltage at the anode when a constant current is passed from the constant current source to the ground via the diode, and a second test current is passed from the ground terminal of the electronic circuit to the ground, A third means for determining the electrical connection state of the ground connection portion of the number of mounted components based on the first voltage and the second voltage, Equipped with, The recording device according to claim 1.

3. The aforementioned connection state is whether the number of electrically connected ground connection parts among the number of implemented ground connection parts is equal to the number of implemented parts. The third means determines whether the number of connected ground connections is equal to the number of implemented units, based on the difference between the first voltage detected by the first means and the second voltage detected by the second means, and the difference between the first voltage and the second voltage when the number of electrically connected ground connections is equal to the number of implemented units. The recording device according to claim 2.

4. The aforementioned connection state refers to the number of electrically connected ground connection parts among the number of implemented ground connection parts, The third means determines the number of electrically connected ground connections based on the difference between the first voltage detected by the first means and the second voltage detected by the second means, and the difference between the first voltage and the second voltage corresponding to the number of electrically connected ground connections. The recording device according to claim 2.

5. The determination means is A fourth means for causing the voltage detection circuit to detect a third voltage at the anode when a constant current is passed from the constant current source to the ground via the diode, and a third test current is passed from the ground terminal of the electronic circuit to the ground, A fifth means for causing the voltage detection circuit to detect the fourth voltage of the anode when a constant current is supplied from the constant current source to the ground via the diode, and no test current is supplied from the ground terminal of the electronic circuit to the ground, A sixth means for determining the electrical connection state of the ground connection portion of the number of mounted components based on the third voltage and the fourth voltage, Equipped with, The recording device according to claim 1.

6. The aforementioned connection state is whether the number of electrically connected ground connection parts among the number of implemented ground connection parts is equal to the number of implemented parts. The sixth means determines whether the number of connected ground connections is equal to the number of implemented units, based on the difference between the third voltage detected by the fourth means and the fourth voltage detected by the fifth means, and the difference between the third voltage and the fourth voltage when the number of electrically connected ground connections is equal to the number of implemented units. The recording device according to claim 5.

7. The aforementioned connection state refers to the number of electrically connected ground connection parts among the number of implemented ground connection parts, The sixth means determines the number of electrically connected ground connections based on the difference between the third voltage detected by the fourth means and the fourth voltage detected by the fifth means, and the difference between the third voltage and the fourth voltage corresponding to the number of electrically connected ground connections. The recording device according to claim 5.

8. The determination means is A seventh means for causing the voltage detection circuit to detect the fifth voltage at the anode when a constant current is passed from the constant current source to the ground via the diode, and a fourth test current is passed from the ground terminal of the electronic circuit to the ground, An eighth means for determining the electrical connection state of the ground connection portion of the number of mounted components based on the fifth voltage, Equipped with, The recording device according to claim 1.

9. The aforementioned connection state is whether the number of electrically connected ground connection parts among the number of implemented ground connection parts is equal to the number of implemented parts. The eighth means determines whether the number of connected ground connections is equal to the number of implemented units, based on the fifth voltage detected by the seventh means and the fifth voltage when the number of electrically connected ground connections is equal to the number of implemented units. The recording device according to claim 8.

10. The aforementioned connection state refers to the number of electrically connected ground connection parts among the number of implemented ground connection parts, The eighth means determines the number of electrically connected ground connections based on the fifth voltage detected by the seventh means and the fifth voltage corresponding to the number of electrically connected ground connections. The recording device according to claim 8.

11. The determination means is A means for repeatedly passing a constant current from the constant current source to the ground via the diode, and detecting the voltage at the anode when a test current is passed from the ground terminal of the electronic circuit to the ground using the voltage detection circuit, for a plurality of test currents, A means for determining the electrical connection state of the ground connection portion of the number of implemented units based on the plurality of test currents and the voltages of the plurality of anodes corresponding to the plurality of test currents, Equipped with, The recording device according to claim 1.

12. The aforementioned connection state is whether the number of electrically connected ground connections among the number of implemented ground connections is equal to the number of implemented ground connections. The recording device according to claim 1.

13. The aforementioned connection state refers to the number of electrically connected ground connection parts among the number of implemented ground connection parts. The recording device according to claim 1.

14. The system further includes means for outputting a warning if the connection status of at least some of the ground connections among the aforementioned number of implemented ground connections is not normal. The recording device according to claim 1.

15. The system further includes a temperature detection means for detecting the temperature of the recording head based on the voltage of the anode. The recording device according to claim 1.

16. The temperature detection means includes means for correcting the detected temperature based on the connection state. The recording device according to claim 15.

17. The determination means is Even if control is performed to supply a constant current from the constant current source to the ground via the diode, if the voltage of the anode detected by the voltage detection circuit is the voltage when the diode is in a non-conducting state, it is determined that there is no electrically connected ground connection among the number of ground connections, or that the anode of the diode is not connected to the constant current source and the voltage detection circuit. The recording device according to claim 1.

18. The determination means further comprises means for outputting a warning if it determines that there are no electrically connected ground connections among the number of ground connections, or that the anode of the diode is not connected to the constant current source and the voltage detection circuit. The recording device according to claim 17.

19. The constant current source and the voltage detection circuit are further comprising: The recording device according to claim 1.

20. The recording head further comprises the aforementioned recording head, The recording device according to claim 1.

21. The recording head is equipped with the constant current source and the voltage detection circuit. The recording device according to claim 20.

22. A method for determining the connection status between a recording head that ejects liquid and a recording device on which the recording head is detachably mounted, The recording head is equipped with a diode and an electronic circuit, the anode of the diode is connected to a constant current source for supplying a constant current to the diode and a voltage detection circuit for detecting the voltage of the anode relative to the ground of the recording device body, the cathode of the diode and the ground terminal of the electronic circuit can be connected to the ground via each of the number of ground connection points mounted. The aforementioned determination method is, A determination step in which a constant current is passed from the constant current source to the ground via the diode, and a test current is passed from the ground terminal of the electronic circuit to the ground, and the electrical connection state of the ground connection portion of the number of mounted units is determined based on the voltage of the anode detected by the voltage detection circuit. A method for determining the thumbnail.

23. A program for causing a computer mounted on a recording device or a computer connected to a recording device to execute a determination method for determining the connection status between a recording head that ejects liquid and a recording device on which the recording head is detachably mounted, The recording head is equipped with a diode and an electronic circuit, the anode of the diode is connected to a constant current source for supplying a constant current to the diode and a voltage detection circuit for detecting the voltage of the anode relative to the ground of the recording device body, the cathode of the diode and the ground terminal of the electronic circuit can be connected to the ground via each of the number of ground connection points mounted. The program is installed on the computer. A determination step in which a constant current is passed from the constant current source to the ground via the diode, and a test current is passed from the ground terminal of the electronic circuit to the ground, and the electrical connection state of the ground connection portion of the number of mounted units is determined based on the voltage of the anode detected by the voltage detection circuit. A program that executes the command.

24. A program for causing a recording device to execute a determination method for determining the connection status between a recording head that ejects liquid and a recording device on which the recording head is detachably mounted, The recording head is equipped with a diode and an electronic circuit, the anode of the diode is connected to a constant current source for supplying a constant current to the diode and a voltage detection circuit for detecting the voltage of the anode relative to the ground of the recording device body, the cathode of the diode and the ground terminal of the electronic circuit can be connected to the ground via each of the number of ground connection points mounted. The program is recorded in the recording device. A determination step in which a constant current is passed from the constant current source to the ground via the diode, and a test current is passed from the ground terminal of the electronic circuit to the ground, and the electrical connection state of the ground connection portion of the number of mounted units is determined based on the voltage of the anode detected by the voltage detection circuit. To execute program.

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