Recording device, method and program

Abstract

To enable relatively simple determination of the ink discharge mode in an ink jet recording apparatus.SOLUTION: A recording apparatus according to the present invention is the recording apparatus that includes a recording head in which a plurality of nozzles that can discharge ink are arranged, and includes: a first detection unit that detects a predetermined parameter for each nozzle; a determination unit that determines the ink discharge state at the corresponding nozzle by comparing a signal based on a detection result of the first detection unit with a threshold; and a threshold generation unit that generates the threshold. The apparatus has, as operation modes, a first mode in which the threshold is a variable value, and a second mode in which the threshold is a fixed value. In the first mode, the determination unit performs a predetermined number of determinations for each nozzle, the threshold generation unit changes the threshold in each of the predetermined number of determinations, and the threshold for the second mode is determined on the basis of the results of the predetermined number of determinations.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates mainly to an inkjet printing apparatus. [Background technology]

[0002] Some recording devices, such as inkjet printers, perform recording by ejecting ink from the nozzles of a recording head. In a recording head using heater elements, ink is ejected from the nozzles upon receiving thermal energy, and it is therefore possible to determine whether the ink has been ejected properly based on the temperature of the ink inside the nozzles (see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2012-250511 Summary of the Invention [Problem to be solved by the invention]

[0004] Generally, a print head has an array of nozzles. The above determination is performed for each of the nozzles by comparing a signal value based on the ink temperature with a threshold value, thereby making it possible to identify non-ejecting nozzles. Here, since the ink ejection pattern may differ between nozzles, it is conceivable to set the threshold value for each nozzle.

[0005] An exemplary object of the present invention is to make it possible to relatively easily determine the ink ejection mode in an inkjet recording apparatus. [Means for solving the problem]

[0006] One aspect of the present invention relates to a recording device, the recording device comprising: A recording apparatus having a recording head in which a plurality of nozzles capable of ejecting ink are arranged, a first detector for detecting a predetermined parameter for each nozzle; a determination unit that compares a signal based on the detection result of the first detection unit with a threshold value to determine the ink ejection state of the corresponding nozzle; a threshold value generating unit that generates a threshold value, As an operation mode, a first mode in which the threshold is variable; A second mode in which the threshold is a fixed value; It has In the first mode, the determination unit performs the determination for each nozzle a predetermined number of times, and the threshold value generation unit changes the threshold value for each of the predetermined number of determinations, and the threshold value for the second mode is determined based on the results of the predetermined number of determinations. 、 the recording apparatus further comprises a non-ejection detection unit that detects a non-ejection nozzle from the plurality of nozzles, In the second mode, the determination unit performs the determination for each nozzle a predetermined number of times, the threshold value generation unit generates the determined threshold value for each of the predetermined number of determinations, and the non-discharge detection unit detects non-discharge nozzles from the plurality of nozzles based on the results of the predetermined number of determinations, The determination unit determines whether the corresponding nozzle has failed to eject based on the result of the comparison, and the failure detection unit includes a measurement unit that measures the number of failures obtained by the determination of the determination unit, and detects the non-ejecting nozzle based on the result of the measurement. R It is characterized by: [Effects of the Invention]

[0007] According to the present invention, the above determination can be realized relatively easily. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 2 is a block diagram showing an example of the configuration of a head control unit and a recording head. [Figure 2] FIG. 1 is a block diagram showing an example of the configuration of a recording apparatus. [Figure 3] FIG. [Figure 4] FIG. 2 is a schematic diagram showing an example of an arrangement of nozzles in a recording head. [Figure 5] FIG. 4 is a diagram showing changes in ink temperature. [Figure 6] 10 is a flowchart for determining whether ejection is normal or not. [Figure 7] 10A and 10B are diagrams showing examples of determination results of the ejection mode of each nozzle. [Figure 8] FIG. 10 is a schematic diagram of a memory area of ​​a non-ejection count storage unit. DETAILED DESCRIPTION OF THE INVENTION

[0009] Hereinafter, embodiments will be described in detail with reference to the accompanying drawings. Note that the following embodiments do not limit the scope of the claimed invention. Although multiple features are described in the embodiments, not all of these multiple features are necessarily essential to the invention, and multiple features may be combined arbitrarily. Furthermore, in the accompanying drawings, the same reference numerals are used to designate the same or similar components, and redundant explanations will be omitted.

[0010] (Example of recording device configuration) 2 is a block diagram showing an example of the configuration for realizing the functions of a recording device 201 according to an embodiment. The recording device 201 includes, for example, a CPU 211, a ROM 212, a RAM 214, a host interface (I / F) unit 213, an image processing unit 215, a head control unit 101, and a recording head 102. These are directly or indirectly connected via a system bus, and perform information processing or signal processing, which will be described in detail later, to enable desired recording using the recording head 102. In this embodiment, the print head 102 is configured to be capable of performing printing by an inkjet method. Typically, the print head 102 has an array of nozzles, and printing is performed by energizing corresponding heater elements (electrothermal conversion elements) to drive them and eject ink from each nozzle. Here, printing refers to forming images, including characters, symbols, figures, patterns, photographs, etc., on a sheet-like recording medium, and the concept of an image also includes any blank spaces that may be formed between them.

[0011] A CPU (Central Processing Unit) 211 reads and executes a control program stored in a ROM (Read Only Memory) 212 to drive and control each element of the recording device 201. For example, information (e.g., information indicating an image or image data, information for realizing the recording thereof, etc.) input from a host PC 202, which is an external device, is stored in a RAM (Random Access Memory) 214 via a host I / F unit 213. The CPU 211 converts the image data into recording data using an image processing unit 215 based on the information stored in the RAM 214, and then realizes the desired recording using a head control unit 101 and a recording head 102 based on the recording data.

[0012] (Regarding recording with a recording head) 3(a) and 3(b) are partial schematic diagrams of a recording device 201 showing how recording is performed by the recording head 102, with FIG. 3(a) showing a side view and FIG. 3(b) showing a top view. The recording device 201 further includes a transport path 301, a paper feed unit 302, and a paper discharge unit 303. The recording device 201 is configured to be capable of color printing, and the recording head 102 includes multiple heads 102a, 102b, 102c, and 102d capable of ejecting ink of different colors. A recording medium supplied from the paper feed unit 302 is transported along the transport path 301, during which ink of the corresponding color is ejected from the head 102a, etc. onto the recording medium (recording is performed), and the recording medium is then discharged from the paper discharge unit 303. It should be noted that ink ejection from a nozzle is achieved by energizing and driving the corresponding heater element, but in the following description, for convenience, this may be referred to as driving the nozzle.

[0013] 4 is a schematic diagram showing an example of the arrangement of nozzles in the print head 102. In this embodiment, a plurality of nozzles are arranged to form a plurality of (eight in this example) nozzle rows in the direction of transport of the print medium, and each nozzle row has a number of nozzles arranged in the nozzle row direction that corresponds to the print width. Note that the X direction in the figure corresponds to the direction of transport of the print medium, and the Y direction in the figure corresponds to the nozzle row direction.

[0014] (Regarding printing operation and determining whether ejection is normal or not) 1 is a block diagram showing an example of the configuration for realizing the functions of a head control unit 101 and a print head 102. The head control unit 101 includes an ejection data generation unit 103 and a non-discharge detection unit 104. The ejection data generation unit 103 includes an ejection data storage unit 121, a threshold value storage unit 122, a threshold value generation unit 123, and an ejection data transfer unit 124. The non-discharge detection unit 104 includes a non-discharge determination result receiving unit 131, a non-discharge count measurement unit 132, and a non-discharge count storage unit 133. The print head 102 includes an ejection data receiving unit 111, a nozzle driving unit 112, a temperature detection unit 113, a non-discharge determination unit 114, and a non-discharge determination result transfer unit 115.

[0015] After the print data is transferred to the head control unit 101, the ejection data generation unit 103 reads out the ejection data generated based on the print data from the ejection data storage unit 121. The ejection data is used to cause each nozzle to eject ink, and includes a group of signals for driving each of the multiple nozzles. Furthermore, as will be described in detail later, threshold data is generated by a threshold generation unit 123 based on information read from the threshold storage unit 122. The threshold data is used to determine whether or not the ink ejection from each nozzle has been properly realized, and includes a plurality of thresholds corresponding to the plurality of nozzles, respectively. The ejection data and threshold data are transferred to the print head 102 by an ejection data transfer unit 124 .

[0016] In the print head 102, the ejection data receiving unit 111 receives the transferred ejection data and threshold data, and outputs them to the nozzle driving unit 112 and the non-ejection determination unit 114, respectively. The nozzle driving unit 112 drives each nozzle based on the ejection data to eject ink. The temperature detection unit 113 detects the temperature of the ink in the driven nozzle (or the temperature of the nozzle) as a detected temperature, and transfers a signal indicating the result to the non-ejection determination unit 114. The non-ejection determination unit 114 compares a signal value based on the signal received from the temperature detection unit 113 (a signal indicating the detected temperature) with the corresponding threshold indicated by the threshold data, and determines whether or not the nozzle has properly ejected ink.

[0017] In the head control unit 101, the non-discharge determination result receiving unit 131 receives the determination result from the non-discharge determination unit 114. In response to this, the non-discharge count measuring unit 132 measures the number of non-discharges (the number of times a non-discharge was determined, i.e., the number of times the above-mentioned discharge was not properly realized. The number of non-discharges may also be expressed as the number of non-discharge determinations), and stores the result in the non-discharge count storage unit 133.

[0018] Figure 5(a) shows how the temperature of the ink inside a nozzle changes when the nozzle is driven. Figure 5(b) shows the signal waveform of the detection result Vdif from the temperature detection unit 113. In the figure, the waveform when ink is ejected properly (in the case of normal ejection) is shown by a solid line, and the waveform when this is not the case (in the case of non-ejection) is shown by a dashed line. As can be seen from Figures 5(a) and 5(b), after the nozzle is driven, the temperature of the ink drops relatively sharply in the case of normal ejection, but drops relatively slowly in the case of non-ejection. Based on such changes in the signal waveform, the discharge failure determination unit 114 calculates the amount of change over time in the detected temperature acquired by the temperature detection unit 113, and determines whether discharge is normal or not by comparing it with threshold data. The result of the determination by the discharge failure determination unit 114 is transferred to the head control unit 101 by the discharge failure determination result transfer unit 115.

[0019] Fig. 5(c) shows the signal waveform of the amount of change over time Vinv in the temperature detected by the temperature detection unit 113 calculated by the discharge failure determination unit 114, i.e., the waveform obtained by performing a differential process on the signal of Fig. 5(b). In order to determine whether discharge is normal or not, it is necessary to set a threshold value between the maximum value Dth1 of the amount of change Vinv in the case of normal discharge and the maximum value Dth2 of the amount of change Vinv in the case of a discharge failure. The manner in which the ink temperature changes may differ depending on the nozzle (variation in change may occur between nozzles). For this reason, it is advisable to set a threshold value for each nozzle. Details will be described later, but in this embodiment, the value obtained by subtracting a predetermined value Dthm from Dth1, which is specified for each nozzle, is used as the threshold value Dth0 for determining whether ejection is normal or not. In other words, if the amount of change in the detected temperature over time, Vinv, reaches the threshold value Dth0, it is determined that ejection is normal, and if not, it is determined that ejection is not normal. The threshold value Dth0 may also be expressed as a threshold voltage, a reference value, a reference voltage, etc.

[0020] Although details will be described later, the threshold storage unit 122 stores reference values ​​of threshold data for making the above determination for each nozzle, and the threshold generation unit 123 generates threshold data based on these reference values ​​and outputs it to the ejection data transfer unit 124. In this embodiment, the threshold generation unit 123 generates threshold data by adding an offset value Dthofs to the reference value.

[0021] 8 is a schematic diagram of the memory area of ​​the non-discharge count storage unit 133. As described above, the non-discharge count storage unit 133 stores the number of non-discharges measured by the non-discharge count measurement unit 132. In this example, it is possible to measure up to 15 non-discharge counts for each nozzle in eight nozzle rows (8,192 nozzles per row). In this way, by storing the number of non-discharges in the non-discharge count storage unit 133 rather than the results of the above determinations themselves, it is possible to reduce the memory size.

[0022] (How to determine whether discharge is normal or not) For ease of explanation, a nozzle that is determined to be non-ejectable will be referred to as a non-ejectable nozzle in the following explanation. A non-ejectable nozzle can be excluded from the targets to be driven in the subsequent printing operation. The recording apparatus 201 according to this embodiment has two operating modes: a threshold value identification mode (first mode) and a non-discharge nozzle detection mode (second mode). In the threshold value identification mode, a threshold value Dth0 for detecting non-discharge nozzles can be searched for and calculated or identified for each nozzle. In the non-discharge nozzle detection mode, the threshold value Dth0 identified in the threshold value identification mode can be used to detect or identify non-discharge nozzles from among multiple nozzles.

[0023] Fig. 6(a) is a flowchart showing the calculations performed by the CPU 211 in the threshold value identification mode, Fig. 6(b) is a flowchart showing the calculations performed in the non-discharge nozzle detection mode, and Fig. 6(c) is a flowchart showing the calculations performed by the head control unit 101 during execution of the flowcharts for the threshold value identification mode and non-discharge nozzle detection mode.

[0024] - Threshold specific mode Referring to FIG. 6(a), in the threshold specification mode, In step S01 (hereinafter simply referred to as "S01," and the same applies to other steps described below), the CPU 211 determines whether the results of the previous threshold determination mode (i.e., the threshold Dth0 determined for the previous detection of non-discharge nozzles) are stored in the RAM 214. If the results of the previous threshold determination mode are stored in the RAM 214, the process proceeds to S02; if not, the process proceeds to S04.

[0025] In S02, the CPU 211 determines whether to use the results of the previous threshold value identification mode stored in the RAM 214. This determination may be made based on, for example, a previous user setting. If the results of the previous threshold value identification mode are to be used, the process proceeds to S03; if not, the process proceeds to S04.

[0026] In S03, the CPU 211 stores the result of the previous threshold value specification mode in the threshold value storage unit 122.

[0027] In S04, the CPU 211 stores the initial value of the threshold in the threshold storage unit 122. This initial value is a fixed value that is set in advance and is common to all the nozzles.

[0028] In S05, the CPU 211 sets a reference value of the threshold data in the threshold storage unit 122, and sets the offset value Dthofs to be added by the threshold generation unit 123 to 0. Details will be described later, but in the threshold identification mode, a threshold that satisfies the conditions is searched for while adding the offset value Dthofs to this reference value.

[0029] In S20, the CPU 211 sets various parameters for the head control unit 101 to drive the print head 102 and performs processing to determine the ejection state (normal ejection / non-ejection). S20 includes S21 to S23, as shown in FIG. 6(c).

[0030] In S21, the head control unit 101 outputs ejection data to the print head 102 to drive the nozzles in a predetermined order, and obtains the determination results regarding the ejection state of each nozzle.

[0031] In S22, the head control unit 101 determines the ejection mode a predetermined number of times. The number of determinations can be determined, for example, by a user setting in advance, but may also be a fixed value (for example, 15 times).

[0032] In S22b, the head control unit 101 determines whether or not the determination of the ejection mode has been completed, and if the determination has been completed, ends this flowchart, otherwise proceeds to S23.

[0033] In S23, the head control unit 101 adds the additional value Dthadd to the offset value Dthofs. Note that, although a positive value is typically used for the additional value Dthadd, a negative value may also be used (a subtraction value may also be used). In this way, the ejection mode for each nozzle is determined using threshold data that is updated for each determination.

[0034] In S09, the CPU 211 reads out the number of non-discharges for each nozzle stored in the non-discharge count storage unit 133, and determines whether the read-out number of non-discharges is within the valid range. If the read-out number of non-discharges is within the valid range, the process proceeds to S10; if not (outside the valid range), the process proceeds to S11. The valid range may be set in advance together with upper and lower limit values ​​that allow proper determination of normal discharge / non-discharge. The valid range may also be expressed as an acceptable range, a reference range, or the like.

[0035] In S11 (when the number of non-discharges is outside the valid range), the CPU 211 updates the reference value of the threshold data, and if the number of non-discharges is greater than the upper limit of the valid range, updates the reference value to a smaller value, and if the number of non-discharges is less than the lower limit of the valid range, updates the reference value to a larger value. The updated reference value is stored in the threshold storage unit 122, and then the process returns to S05 and the above determination is made again.

[0036] In S10 (when the number of non-ejection occurrences is within the valid range), the CPU 211 calculates the aforementioned values ​​Dth1 and Dth0 (see FIG. 5(c)). In this embodiment, the value Dth1 is obtained by adding the value obtained by multiplying the addition value Dthadd by the number corresponding to the number of times that ejection has been determined to be normal to the reference value of the set threshold data. That is, Dth1=Dx+Dthadd×(N-1) Dx: Reference value of the set threshold data N: Number of normal discharges (value obtained by subtracting the number of non-discharges from the number of judged discharges) This can be expressed as (Equation 1). The threshold value Dth0 is Dth0=Dth1-Dthm Dthm: predetermined value This can be expressed as (Equation 2). The threshold Dth0 thus determined is stored in the RAM 214 as a result of the threshold determination mode.

[0037] As described above, the threshold value Dth0 is set to a value between the maximum value Dth1 of the change amount Vinv in the case of normal ejection and the maximum value Dth2 of the change amount Vinv in the case of ejection failure. Therefore, the value Dthm may be any value that is smaller than the difference between the values ​​Dth1 and Dth2, and for example, a calculated value based on the values ​​Dth1 and Dth2 (e.g., an average value, a median value, etc.) may be specified in advance as a typical value of the value Dthm. Similarly, the sum Dthadd is required to be smaller than the difference between the values ​​Dth1 and Dth2, and in particular, since the value Dth1 is changed sequentially in S20, a value smaller than the value Dthm can be set as the typical value of the sum Dthadd.

[0038] 7(a) and 7(b) show an example of the judgment results of the ejection mode in the threshold specific mode for four nozzles, seg0 to seg3, with the number of judgments set to 15, the reference value Dx of the threshold data set to 80, and the additional value Dthadd set to 2. Fig. 7(a) shows an example of the judgment results when not affected by noise, while Fig. 7(b) shows an example of the judgment results when affected by noise.

[0039] In the example of FIG. 7(a), the number of non-discharges for each nozzle is 10 times for the nozzle of seg0, 14 times for the nozzle of seg1, 0 times for seg2 nozzle, 15 times for the seg3 nozzle, Let's say. In this case, if the effective range of the number of ejection failures is set to 1 or more and 14 or less, and the above (Equation 1) is referred to, the calculated threshold value Dth1 for each nozzle is 88 for nozzle in seg0, 80 for seg1 nozzle, Invalid for nozzle seg2 (threshold Dth1 cannot be calculated or identified), Disabled for seg3 nozzle, In this way, for the nozzles of seg0 and seg1, the threshold value Dth0 is determined based on the above (Equation 2).

[0040] In the example of FIG. 7(b), the number of non-discharges for each nozzle is 10 times for the nozzle of seg0, 13 times for the nozzle of seg1, Once for the seg2 nozzle, 14 times for the seg3 nozzle, Let's say. In this case, if the effective range of the number of ejection failures is set to 2 or more and 13 or less, and the above (Equation 1) is referred to, the calculated threshold value Dth1 for each nozzle is 88 for nozzle in seg0, 82 for the nozzle of seg1, Disabled for seg2 nozzle, Disabled for seg3 nozzle, In this way, for the nozzles of seg0 and seg1, the threshold value Dth0 is determined based on the above (Equation 2).

[0041] For the nozzles in seg2 and seg3 that are determined to be invalid, the reference value Dx is updated in S11, and an appropriate threshold value Dth1 is searched for again in S05, S20, and S09. The valid range may be set based on the degree of noise.

[0042] - Non-discharge nozzle detection mode Referring to FIG. 6(b), in the non-ejection nozzle detection mode, the result of the threshold specification mode described above is used. In S03′, the CPU 211 stores the result of the threshold value identification mode stored in the RAM 214 in the threshold value storage unit 122.

[0043] In S05', the CPU 211 sets the offset value Dthofs, which is added by the threshold generation unit 123, to 0. Here, in the non-discharge nozzle detection mode, the above-mentioned specified threshold is used fixedly (a threshold search is not performed), so the offset value Dthofs remains 0, that is, the added value Dthadd is also set to 0.

[0044] 6(a) (similar to S20 in the threshold specification mode), the CPU 211 performs processing to determine the ejection mode by driving the head control unit 101. In this step, the number of determinations in S22 and S22b may be the same as or different from that in the threshold specification mode.

[0045] In S09', the CPU 211 determines whether the number of non-discharge events is smaller than a predetermined value for each nozzle. If the number of non-discharge events is smaller than the predetermined value, the process proceeds to S12, and if not, the process proceeds to S13.

[0046] In S12, the CPU 211 identifies the target nozzle as one capable of normal ejection.

[0047] In S13, the CPU 211 identifies the target nozzle as a non-ejecting nozzle.

[0048] Although "'" has been added above for the purpose of distinction, S03', S05', S20', and S09' of the non-discharge nozzle detection mode can be realized by the same program as S03, S05, S20, and S09 of the threshold value identification mode, respectively. For example, S05' is realized by the same processing as S05, except that the setting value of the additional value Dthadd is different.

[0049] As described above, according to this embodiment, in the threshold specification mode, a normal discharge / non-discharge determination is performed multiple times while changing the threshold Dth1 in order to identify the threshold Dth0 that should be set. When a threshold Dth1 that satisfies the conditions is calculated, the threshold Dth0 is specified based on the above (Equation 2) and set as the threshold for the non-discharge nozzle detection mode. In the threshold specification mode, the threshold Dth1 is sequentially changed in order to identify the threshold Dth0, and the changed threshold Dth1 is set provisionally. Therefore, the threshold specification mode can be said to be an operating mode in which the threshold is a variable value. On the other hand, in the non-discharge nozzle detection mode, the threshold value Dth0 specified in the threshold value specification mode is used to determine whether discharge is normal or not. This makes it possible to properly detect non-discharge nozzles from multiple nozzles. In the non-discharge nozzle detection mode, the threshold value Dth0 specified in the threshold value specification mode is used as a fixed value. Therefore, the non-discharge nozzle detection mode can be said to be an operating mode in which the threshold value is a fixed value.

[0050] This operation makes it relatively easy to determine the ink ejection mode in the inkjet recording apparatus 201. From the above perspective, the threshold value Dth1 may be distinguished by being expressed as a variable threshold value, a provisional threshold value, or the like, and the threshold value Dth0 may be distinguished by being expressed as a fixed threshold value, a determined threshold value, or the like.

[0051] Furthermore, according to this embodiment, the non-discharge count measurement unit 132 measures the number of non-discharges, and the non-discharge count storage unit 133 stores the measured number of non-discharges, so it is also possible to reduce the memory size of the non-discharge count storage unit 133. Therefore, according to this embodiment, it can be said that the determination can be realized even more simply.

[0052] In this embodiment, the determination of normal ejection / non-ejection is made based on the temperature detected by the temperature detection unit 113, but as another example, it may be made based on the amount of current through the heater element when driving the nozzle. Also, in this embodiment, the nozzle is driven by driving the heater element, but in another embodiment, if the nozzle is driven by driving a piezoelectric element, the above determination may be made based on residual vibration.

[0053] (program) The present invention may be realized by supplying a program that realizes one or more functions of the above-described embodiments to a system or device via a network or a storage medium, and having one or more processors in a computer of the system or device read and execute the program. For example, the present invention may be realized by a circuit (e.g., an ASIC) that realizes one or more functions.

[0054] (others) In the above description, a recording apparatus using an inkjet recording method has been used as an example, but the recording method is not limited to the above. Furthermore, the recording apparatus may be a single-function printer having only a recording function, or a multi-function printer having multiple functions such as a recording function, a fax function, and a scanner function. Furthermore, the recording apparatus may be, for example, a manufacturing apparatus for manufacturing color filters, electronic devices, optical devices, microstructures, etc. using a predetermined recording method.

[0055] Furthermore, the term "recording" as used in this specification should be interpreted broadly. Therefore, the form of "recording" does not matter whether the object formed on the recording medium is significant information such as characters or figures, or whether it is visible to humans or not.

[0056] Furthermore, the term "recording medium" should be interpreted broadly, just like the above-mentioned "recording." Therefore, the concept of "recording medium" can include not only commonly used paper, but also any material that can accept ink, such as cloth, plastic film, metal plate, glass, ceramics, resin, wood, leather, etc.

[0057] Furthermore, "ink" should be interpreted broadly, just like the above-mentioned "recording." Therefore, the concept of "ink" includes not only a liquid that is applied to a recording medium to form an image, design, pattern, etc., but also ancillary liquids that can be used for processing the recording medium, treating the ink (for example, solidifying or insolubilizing coloring materials in ink applied to the recording medium), etc. From this perspective, a recording device may be referred to as a liquid ejection device, and for the same purpose, a recording head may be referred to as a liquid ejection head.

[0058] Furthermore, in the embodiments, individual elements are named based on their main functions, but the functions described in the embodiments may be sub-functions and are not strictly limited to these expressions. Furthermore, these expressions can be replaced with similar expressions. For the same purpose, the expression "unit" can be replaced with "tool," "component," "member," "structure," "assembly," etc. Alternatively, these terms may be omitted or added.

[0059] Furthermore, two or more selectable elements exemplified in the embodiments are not strictly limited to the examples and may be arbitrarily combined, for example, each of the two or more selectable elements may be additionally or alternatively selected. For example, when two elements A and B are arbitrarily combined, they may be expressed as "A and / or B" or "at least one of A and B" to indicate either A only, B only, or both A and B.

[0060] (Summary of the embodiment) Some of the features exemplified in the embodiments are as follows: [1] A recording apparatus having a recording head in which a plurality of nozzles capable of ejecting ink are arranged, a first detector for detecting a predetermined parameter for each nozzle; a determination unit that compares a signal based on the detection result of the first detection unit with a threshold value to determine the ink ejection state of the corresponding nozzle; a threshold value generating unit that generates a threshold value, As an operation mode, a first mode in which the threshold is variable; A second mode in which the threshold is a fixed value; It has In the first mode, the determination unit performs the determination for each nozzle a predetermined number of times, the threshold value generation unit changes the threshold value for each of the predetermined number of determinations, and the threshold value for the second mode is determined based on the results of the predetermined number of determinations. A recording device characterized by: [2] a non-ejection detection unit for detecting a non-ejection nozzle from the plurality of nozzles, In the second mode, the determination unit performs the determination for each nozzle a predetermined number of times, the threshold value generation unit generates the determined threshold value for each of the predetermined number of determinations, and the non-discharge detection unit detects non-discharge nozzles from the plurality of nozzles based on the results of the predetermined number of determinations. The recording device according to [1]. [3] the determining unit determines whether the corresponding nozzle is non-ejecting based on the result of the comparison, The non-discharge detection unit includes a measurement unit that measures the number of non-discharges obtained by the determination by the determination unit, and detects non-discharge nozzles based on the results of the measurement. The recording device according to [2]. [4] the print head includes heater elements for driving individual nozzles; The first detection unit is a temperature detection unit that detects the temperature of the ink in each nozzle. The recording device according to any one of [1] to [3], characterized in that: [5] The signal based on the detection result of the temperature detection unit is obtained by performing a differential process on the signal corresponding to the temperature of the ink detected by the temperature detection unit. The recording device according to [4], [6] In the first mode, the threshold value generating unit changes the threshold value by adding or subtracting from a reference value in each of the predetermined number of determinations. The recording device according to any one of [1] to [5], characterized in that: [7] In the first mode, if the number of ejection failures obtained by the predetermined number of determinations for a certain nozzle is outside the valid range, the threshold value generation unit updates the reference value and changes the threshold value for that nozzle, and the determination unit performs the predetermined number of determinations again. The recording device according to [6]. [8] The threshold generation unit If the number of non-discharge occurrences obtained by the predetermined number of determinations is greater than the upper limit of the effective range, the reference value is updated to a smaller value; If the number of non-discharge occurrences obtained by the predetermined number of determinations is greater than the lower limit of the effective range, the reference value is updated to a larger value. The recording device according to [7]. [9] A method for controlling a printing apparatus having a print head in which a plurality of nozzles capable of ejecting ink are arranged, comprising: detecting a predetermined parameter for each nozzle; a step of comparing a signal based on the detected parameters with a threshold value to determine the ink ejection state of the corresponding nozzle; generating a threshold value; The recording device has the following operation modes: a first mode in which the threshold is variable; A second mode in which the threshold is a fixed value; It has In the first mode, the determination is performed a predetermined number of times for each nozzle, the threshold value is changed for each of the predetermined number of determinations, and the threshold value for the second mode is determined based on the results of the predetermined number of determinations. A method characterized by:

[10] A program for causing a computer to execute each step of the method described in [9]. The program can be stored in a computer-readable non-volatile storage medium.

[0061] The invention is not limited to the above-described embodiments, and various changes and modifications can be made without departing from the spirit and scope of the invention. Accordingly, the following claims are appended to apprise the public of the scope of the invention. [Explanation of symbols]

[0062] 201: recording device, 102: recording head, 113: Temperature detection unit, 114: Discharge failure determination unit, 123: Threshold value generation unit.

Claims

1. A recording apparatus having a recording head in which a plurality of nozzles capable of ejecting ink are arranged, a first detector for detecting a predetermined parameter for each nozzle; a determination unit that compares a signal based on the detection result of the first detection unit with a threshold value to determine the ink ejection state of the corresponding nozzle; a threshold value generating unit that generates a threshold value, As an operation mode, a first mode in which the threshold value is variable; a second mode in which the threshold is a fixed value; It has In the first mode, the determination unit performs the determination for each nozzle a predetermined number of times, the threshold value generation unit changes the threshold value for each of the predetermined number of determinations, and the threshold value for the second mode is determined based on the results of the predetermined number of determinations; the recording apparatus further comprises a non-ejection detection unit that detects a non-ejection nozzle from the plurality of nozzles, In the second mode, the determination unit performs the determination for each nozzle a predetermined number of times, the threshold value generation unit generates the determined threshold value for each of the predetermined number of determinations, and the non-discharge detection unit detects non-discharge nozzles from the plurality of nozzles based on the results of the predetermined number of determinations, The determination unit determines whether the corresponding nozzle has failed to eject based on the result of the comparison, and the failure detection unit includes a measurement unit that measures the number of failures obtained by the determination by the determination unit, and detects the non-ejecting nozzle based on the result of the measurement. A recording device characterized by:

2. the print head includes heater elements for driving individual nozzles; The first detection unit is a temperature detection unit that detects the temperature of the ink in each nozzle.

2. The recording apparatus according to claim 1.

3. The signal based on the detection result of the temperature detection unit is obtained by performing a differential process on the signal corresponding to the temperature of the ink detected by the temperature detection unit.

3. The recording apparatus according to claim 2.

4. In the first mode, the threshold value generating unit changes the threshold value by adding or subtracting from a reference value in each of the predetermined number of determinations.

2. The recording apparatus according to claim 1.

5. In the first mode, if the number of ejection failures obtained by the predetermined number of determinations for a certain nozzle is outside the valid range, the threshold value generation unit updates the reference value and changes the threshold value for that nozzle, and the determination unit performs the predetermined number of determinations again.

5. The recording apparatus according to claim 4.

6. The threshold generation unit If the number of non-discharge occurrences obtained by the predetermined number of determinations is greater than the upper limit of the effective range, the reference value is updated to a smaller value; If the number of non-discharge occurrences obtained by the predetermined number of determinations is greater than the lower limit of the effective range, the reference value is updated to a larger value.

6. The recording apparatus according to claim 5.

7. A method for controlling a printing apparatus having a print head in which a plurality of nozzles capable of ejecting ink are arranged, comprising: detecting a predetermined parameter for each nozzle; a step of comparing a signal based on the detected parameters with a threshold value to determine the ink ejection state of the corresponding nozzle; generating a threshold value; The recording device has the following operation modes: a first mode in which the threshold value is variable; a second mode in which the threshold is a fixed value; It has In the first mode, the determination is performed a predetermined number of times for each nozzle, the threshold value is changed for each of the predetermined number of determinations, and the threshold value for the second mode is determined based on the results of the predetermined number of determinations; The method further includes a step of detecting a non-ejecting nozzle from the plurality of nozzles, In the second mode, the determination is made a predetermined number of times for each nozzle in the step of determining the ejection state, the threshold value is generated for each of the predetermined number of determinations in the step of generating a threshold value, and a non-ejection nozzle is detected from the plurality of nozzles based on the results of the predetermined number of determinations in the step of detecting a non-ejection nozzle, In the step of determining the ejection state, it is determined whether the corresponding nozzle is non-ejecting based on the result of the comparison, and in the step of detecting the non-ejecting nozzle, it is detected based on the result of measuring the number of non-ejections obtained by the determination in the step of determining the ejection state. A method characterized by:

8. A program for causing a computer to execute each step of the method according to claim 7.

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