Recording device, control method thereof, and program

Abstract

To suppress a deterioration rate of a component related to temperature control of ink and shorten the time to the start of re-printing.SOLUTION: A recording device according to one embodiment of the present invention comprises: a recording head which performs recording by discharging ink; an ink passage which includes the recording head and in which the ink flows; heat exchange means which cools or heats the ink in the ink passage; adjustment means which adjusts the temperature of the ink by using the heat exchange means; a pump which supplies the ink to the recording head through the ink passage; and control means which controls the adjustment means and the pump. The control means controls the adjustment means and the pump so as to obtain the target value of the temperature of the ink set in the printing state, and controls the adjustment means and the pump so as to hold the temperature of the ink within a first temperature range set in the non-printing state in the adjustment means. The target value is included in the first temperature range.SELECTED DRAWING: Figure 5

Description

[Technical field]

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

[0002] Conventionally, some inkjet printers, which eject ink from nozzles in a recording head to print on a recording medium such as printing paper, are of an ink circulation type that circulates the ink to cool the ink and remove dirt from the ink flow path. If the temperature of the ink circulating inside the ink circulation supply mechanism of such inkjet printers is not within a predetermined temperature range, the ink viscosity may change more than the designer had anticipated, resulting in non-ejection or an increase or decrease in the ejection amount, which may degrade the image quality.

[0003] Patent document 1 discloses that in order to prevent degradation of image quality caused by changes in ink viscosity due to changes in ink temperature, a temperature change means is provided that heats or cools the ink so that the ink temperature falls within a predetermined temperature range. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2009-196208 A Summary of the Invention [Problem to be solved by the invention]

[0005] In a large inkjet recording device, since it takes time to start up the device, the power may not be turned off even when the device goes from a printing state to a non-printing state. In such a case, in order to keep the ink temperature within a predetermined temperature range so that reprinting can be started immediately, it is necessary to continue circulating the ink and adjusting the ink temperature for a long period of time until the next print command is received. Alternatively, it is necessary to stop the ink circulation and adjust the ink temperature so that the ink temperature falls within the predetermined temperature range before starting printing when the next print command is received.

[0006] However, in the former case, since ink temperature adjustment is constantly performed, deterioration of components such as the ink circulation pump and ink temperature adjustment device is likely to progress, and in the latter case, ink temperature adjustment must be restarted after receiving a print command, so it takes time before reprinting can begin.

[0007] In view of the above problems, an object of the present invention is to simultaneously suppress the rate of deterioration of parts related to ink temperature control and shorten the time until reprinting can be started. [Means for solving the problem]

[0008] One embodiment of the present invention is a recording device having a recording head that ejects ink to record, an ink path including the recording head and through which the ink flows, a heat exchanger that cools or heats the ink in the ink path, an adjustment means that adjusts the temperature of the ink using the heat exchanger, a pump that supplies the ink to the recording head through the ink path, and a control means that controls the adjustment means and the pump, wherein the control means controls the adjustment means and the pump so that the temperature of the ink reaches a target value set in a printing state, and further controls the adjustment means and the pump so that the temperature of the ink is maintained within a first temperature range set in the adjustment means in a non-printing state, the target value being included in the first temperature range, and the first temperature range is In the printing state The temperature range, In the non-printing statethe target value is included in a second temperature range having a predetermined temperature width with a predetermined temperature as a center temperature, the second temperature range is narrower than the first temperature range, and when the temperature of the ink reaches an upper or lower limit of the first temperature range in the non-printing state and the pump is stopped, the pump is continued to be driven after resumption until the temperature of the ink exceeds the boundary value of the second temperature range and reaches at least one value in the second temperature range. Effect of the Invention

[0009] According to the present invention, it is possible to simultaneously suppress the rate of deterioration of parts related to ink temperature control and shorten the time until reprinting can be started. [Brief description of the drawings]

[0010] [Figure 1] FIG. 1 is an external perspective view of a recording apparatus according to an embodiment of the present invention. [Diagram 2] FIG. 1 is a schematic perspective view showing a recording apparatus according to an embodiment of the present invention during recording. [Diagram 3] FIG. 1 is a conceptual diagram showing ink paths in a recording apparatus according to an embodiment of the present invention; [Figure 4] A conceptual diagram of ink temperature control during printing according to the first embodiment. [Diagram 5] A conceptual diagram of ink temperature control during non-printing according to the first embodiment. [Figure 6] 1 is a flowchart of an ink temperature control process in a recording apparatus according to a first embodiment. [Figure 7] A conceptual diagram of ink temperature control during printing according to the second embodiment. [Figure 8] A conceptual diagram of ink temperature control during non-printing according to the second embodiment. [Figure 9] 11 is a flowchart of an ink temperature control process in a recording apparatus according to a second embodiment. [Figure 10] A conceptual diagram of ink temperature control during non-printing according to the third embodiment. [Figure 11] 13 is a flowchart of an ink temperature control process in a recording apparatus according to a fourth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] Hereinafter, as an example of an inkjet recording device, a high-speed line printer that uses a continuous sheet wound in a roll and supports both single-sided and double-sided printing will be described. Such a high-speed line printer is suitable for mass printing in print laboratories and the like.

[0012] Hereinafter, an embodiment of the present invention will be described in detail with reference to the drawings. In the drawings, the same reference numerals will be assigned to the same or corresponding elements (portions).

[0013] <Structure of the recording device> 1 is a perspective view of the appearance of a recording apparatus 1 according to an embodiment. The recording apparatus 1 has a sheet setting unit 101 for setting a continuous sheet wound in a roll, a paper discharge unit 102 for discharging a recorded sheet, and an operation unit 103.

[0014] FIG. 2 is a perspective view showing the inside of the recording device 1. The recording device 1 is a line printer that performs recording while continuously transporting the sheet 4 in a predetermined direction (this direction is called the sheet transport direction, the first direction, etc.) using a long line head. The recording device 1 further has a holder that holds the sheet 4 such as continuous paper wound in a roll, a transport mechanism 7 that transports the sheet 4 in the first direction at a predetermined speed, and a recording unit 3 that performs recording on the sheet 4 using the line head. Note that the sheet is not limited to a continuous roll sheet, and may be a cut sheet. The recording device 1 further has a cleaning unit 6 that cleans the nozzle surface of the recording head by wiping, a cutter unit that cuts the sheet 4 provided downstream of the recording unit 3 along the sheet transport path, a drying unit that force-dries the sheet, and a discharge tray.

[0015] The recording unit 3 has a plurality of recording heads 2 each corresponding to a different ink color. In this example, as shown in FIG. 2, the plurality of recording heads 2 are four recording heads corresponding to four colors, cyan (C), magenta (M), yellow (Y), and black (K), but the number of colors is not limited to this. Ink of each color is supplied to one of the plurality of recording heads 2 from an ink tank via an ink tube. The plurality of recording heads 2 are held together by a head holder 5, and the head holder 5 can move up and down so that the distance between the plurality of recording heads 2 and the surface of the sheet 4 can be changed.

[0016] <Mechanism that circulates ink and supplies it to the print head> 3 is a conceptual diagram showing ink paths in the recording device 1. The recording device 1 has a buffer tank 10 that functions as a first ink storage tank, and a recording head 2 that performs recording by discharging ink supplied from the buffer tank 10 from a discharge nozzle 8. The recording device 1 also has a first ink path 20 that connects the recording head 2 and the buffer tank 10 on the upstream side of the recording head 2, and a second ink path 30 that connects the recording head 2 and the buffer tank 10 on the downstream side of the recording head 20. In this way, an ink circulation path is formed in a ring shape inside the recording device 1, and during recording (in a printing state), ink circulates from the buffer tank 10 to the first ink path 20 to the recording head 2 to the second ink path 30 to the buffer tank 10, and so on.

[0017] The first ink path 20 is provided with a sub-tank 11 that functions as a second ink storage tank, a first circulation pump 21, a heat exchange means 50, and a filter 60 that removes foreign matter in the ink path, while the second ink path 30 is provided with a second circulation pump 31. As shown in the figure, the portion of the first ink path 20 between the buffer tank 10 and the heat exchange means 50 is referred to as the first ink path 20a. Also, the portion between the heat exchange means 50 and the first circulation pump 21 is referred to as the first ink path 20b, and the portion between the sub-tank 11 and the recording head 2 is referred to as the first ink path 20c.

[0018] The first circulation pump 21 and the second circulation pump 31 employ a tube pump system capable of generating positive and negative pressures by rotating a pump tube in forward and reverse directions while squeezing the pump tube with pump rollers.

[0019] The ink tank 40 is for supplying ink to the inside of the recording device 1 and refilling the ink, and is configured to be detachable from the recording device 1. The ink tank 40 and the recording device 1 are connected by an ink supply tube. An ink supply pump 41 that employs a tube pump system similar to the circulation pumps 21 and 31 is provided in the middle of the ink supply tube extending from the ink tank 40, and the connection destination of the ink supply tube is configured to be the buffer tank 10.

[0020] The buffer tank 10 and the sub-tank 11 each have an air vent at the top of the tank, allowing air bubbles accumulated in each tank to be constantly discharged to the outside of the machine. The buffer tank 10 is located at the highest position in the ink circulation supply path in the recording device 1.

[0021] A first temperature detection means 22 is provided immediately before the print head 2 in the first ink path 20, for detecting the temperature of the ink flowing into the print head 2. Note that, although the print head 2 and the first temperature detection means 22 are configured separately here, the first temperature detection means 22 may be provided integrally inside the print head 2. In the following embodiments, various controls are performed assuming that the temperature of the first temperature detection means 22 is the temperature of the ink in the print head 2.

[0022] A constant temperature medium is stored inside the heat exchange means 50 for adjusting the ink temperature. A metal tube 51 is disposed inside the heat exchange means 50 so as to be immersed in the constant temperature medium. One end (upstream side) of the metal tube 51 is connected to the first ink path 20a, and the other end (downstream side) of the metal tube 51 is connected to the first ink path 20b, so that the metal tube 51 serves as a part of the first ink path 20. The ink passing through the first ink path 20 due to the ink circulation exchanges heat with the constant temperature medium while passing through the metal tube 51, and is heated or cooled to the temperature inside the heat exchange means 50.

[0023] An ink temperature adjustment means 52 that adjusts the temperature of a constant temperature medium for the purpose of adjusting the ink temperature is connected to the heat exchange means 50, and the temperature-adjusted constant temperature medium circulates through a path formed to include the ink temperature adjustment means 52 and the heat exchange means 50. The constant temperature medium may be a liquid including water, or a gas including air.

[0024] The ink temperature adjustment means 52 is composed of components that contribute to adjusting the temperature of the constant temperature medium, specifically, a cooler, a heater, a constant temperature medium circulating pump, a temperature sensor, and the like, all of which are not shown.

[0025] The recording device 1 has an ink temperature control unit 53 that controls the ink temperature adjustment means 52, and the ink temperature control unit 53 controls the operation and stop of the ink temperature adjustment means 52 and the temperature setting. It also controls the operation and stop of the circulation pumps 21, 31. The ink temperature control unit 53 can constantly obtain status information of the recording device 1, including information on the ink temperature detected by the first temperature detection means 22 and information on the internal air temperature detected by the second temperature detection means 32. The ink temperature control unit 53 may be configured to include a CPU, a ROM, a RAM, etc., or may be realized using an electric circuit, etc. The circulation pumps 21, 31 may be configured to be controlled by a control unit different from the ink temperature control unit 53.

[0026] The air temperature inside the recording device 1, for example at start-up, follows the ambient temperature of the recording device 1 (the temperature of the installation location) and is expected to range from low (specifically, about 15°C) to high (specifically, about 40°C). When printing begins, the air temperature inside the recording device 1 rises over time due to factors such as heat generated by driving the motor inside the recording device 1. In this way, the air temperature inside the recording device 1 changes due to various factors. The above is the basic structure of the mechanism that circulates ink and supplies it to the recording head 2 in the embodiment described below.

[0027] [First embodiment] In the following, the ink temperature control during printing and non-printing in the first embodiment will be described with reference to Figs. 4 and 5. Here, in the recording device 1 in this embodiment, the target temperature of the ink temperature of the recording head 2 during printing is set to 37.5°C, and the ink is controlled to be approximately 37.5°C by driving the pump to cause the ink to flow through the metal tube 51. 37.5°C is the temperature at which the ink can maintain a viscosity appropriate for printing in this embodiment. The set target temperature is stored in the ROM of the ink temperature control unit 53.

[0028] <Ink temperature control during printing> The ink temperature control during printing will be described with reference to FIG. 4. Since ink is consumed during printing, it is necessary to supply ink to the recording head 2. Therefore, as shown in FIG. 4, the pump during printing is always driven. During printing, the ink temperature tends to rise due to factors such as ejection from the recording head and the temperature inside the machine. However, the ink temperature may vary depending on the operating conditions of the recording device 1. Therefore, in this embodiment, the first temperature detection means 22 detects the ink temperature just before entering the recording head 2, and the ink temperature control unit 53 controls the temperature adjustment by the ink temperature adjustment means 52 based on the detected ink temperature. In detail, as shown in FIG. 4, cooling is performed in the upper convex part of the 37.5°C line, and heating is performed in the lower convex part. In other words, when the temperature detected by the first temperature detection means 22 is 37.5°C or higher, cooling is performed, and when the detected temperature is less than 37.5°C, heating is performed. As a result, the ink temperature is maintained at around 37.5°C.

[0029] <Temperature control when not printing (when internal temperature is 30.0°C)> Ink temperature control when not printing will be explained with reference to Fig. 5(a) using an example where the internal temperature is 30.0°C. In the graph of Fig. 5(a), the horizontal axis represents time and the vertical axis represents ink temperature, and with respect to the thick line in the figure, the portion up to point A (to the left of point A) represents the change in ink temperature when printing, and the portion after point A (to the right of point A and including point A) represents the change in ink temperature when not printing.

[0030] When printing is completed and the state transitions to a non-printing state, and the driving of the pump is stopped, the temperature inside the machine is lower than the ink temperature, so the ink temperature drops to 34.0°C (point B), which is the lower limit of the predetermined temperature range shown in the figure. Here, the predetermined temperature range is the range of ink temperatures maintained by the ink temperature control of the ink temperature control unit 53, and is referred to as the "ink temperature control range" in this specification. After the ink temperature drops to 34.0°C (point B), the pump driving is resumed. The pump driving after the restart continues until the ink temperature rises to 37.5°C (point C). After that, the pump driving is stopped again and the ink temperature drops to 34.0°C (point D), and thereafter the rise and fall are repeated. In this way, heating is performed when the temperature detected by the first temperature detection means 22 becomes 34.0°C or lower.

[0031] When printing, the target ink temperature is set to 37.5°C and the pump is constantly driven to circulate the ink, maintaining the ink temperature at around 37.5°C. In contrast, when not printing, the pump is driven intermittently to circulate the ink, controlling the ink temperature to fall within the range of 37.5±3.5°C.

[0032] In this manner, in this embodiment, the ink temperature control range is widened when not printing compared to when printing, ensuring time for the pump to be off. This makes it possible to reduce the amount of pump driving, which contributes to extending the life of the pump.

[0033] <Temperature control when not printing (when internal temperature is 45°C)> Ink temperature control when not printing will be explained with reference to Fig. 5(b) using an example where the internal temperature is 45°C. In the graph of Fig. 5(b), the horizontal axis represents time and the vertical axis represents ink temperature, and with respect to the thick line in the figure, the portion up to point A (to the left of point A) represents the change in ink temperature when printing, and the portion after point A (to the right of point A, including point A) represents the change in ink temperature when not printing.

[0034] When printing ends and the machine transitions to a non-printing state and the pump is stopped, the temperature inside the machine is higher than the ink temperature, so the ink temperature rises to 41.0°C (point B), which is the upper limit of the ink temperature control range shown in the figure.

[0035] The ink temperature rises to 41.0°C (point B), then drops to 37.5°C (point C) again when the pump is restarted, and then rises to 41.0°C (point D) when the pump is stopped again, and thereafter repeats rising and falling. In this manner, cooling is performed when the temperature detected by the first temperature detection means 22 is 41.0°C or higher.

[0036] When printing (when the recording device is in a printing state), the target ink temperature is set to 37.5°C and the pump is constantly driven to circulate the ink, so that the ink temperature is maintained at approximately 37.5°C. In contrast, when not printing (when the recording device is in a non-printing state (also called a low-power state)), the pump is driven intermittently to circulate the ink, so that the ink temperature is controlled to fall within the range of 37.5±3.5°C. In this way, when not printing, the ink temperature control range is wider than when printing, ensuring time for the pump to be non-driven. This makes it possible to reduce the amount of pump drive, which contributes to extending the pump's lifespan.

[0037] <Processing flow> The ink temperature control process in this embodiment, specifically, the process of setting a target value for the ink temperature used during printing instead of the ink temperature control range used during non-printing, will be described below with reference to Fig. 6. Note that each process shown in Fig. 6 is executed by the CPU of the ink temperature control unit 53.

[0038] After printing has been completed, in step S601, the ink temperature control range during non-printing is set to 37.5±3.5°C for the ink temperature adjustment means 52. The ink temperature control range during non-printing is set in advance and stored in the ROM of the ink temperature control unit 53. After printing has been completed, the temperature control range stored in the ROM is read out to set the controlled temperature range. As a result, in the subsequent non-printing state, the ink temperature is controlled to always be within the range of 37.5±3.5°C. Note that hereinafter, for simplicity, "Step S~" will be abbreviated as "S~".

[0039] In S602, it is determined whether a print job has been received. If the determination result in this step is true, the process proceeds to S603. On the other hand, if the determination result in this step is false, the process returns to S601. After that, loop processing is performed until a print job is received.

[0040] In S603, 37.5° C. is set as the target value of the ink temperature during printing in the ink temperature adjustment means 52. As a result, in the subsequent printing state, the ink temperature is controlled so as to always be approximately 37.5° C.

[0041] In this embodiment, the ink temperature during printing is set to 37.5°C in S603, but the ink temperature during printing is not limited to this and other values ​​may be used. Also, instead of setting a single value such as 37.5°C for the ink temperature adjustment means 52, a temperature range (ink temperature control range) having a predetermined temperature width with this single value as the center temperature may be set. Furthermore, the temperature or temperature range set in S603 may be variable so that it can be changed midway.

[0042] Similarly, the ink temperature control range during non-printing set in S601 is not limited to 37.5±3.5° C., and other temperature ranges or temperatures (one value) may be used.

[0043] <Effects of this embodiment> As described above, according to this embodiment, by making the non-operation time of the pump longer when not printing than when printing, the amount of pump operation can be reduced compared to when the pump is controlled in the same way when not printing, and the pump life can be extended. Also, in a non-printing state, if the ink temperature is equal to or higher than a predetermined temperature threshold or equal to or lower than a predetermined temperature threshold, the pump operation is resumed, thereby preventing the ink temperature from deviating significantly from the printable temperature range and preventing the time until reprinting can be started from becoming too long.

[0044] Therefore, it is possible to both suppress the rate at which parts deteriorate and shorten the time until reprinting can begin.

[0045] [Second embodiment] In the following, the ink temperature control during printing and non-printing in the second embodiment will be described with reference to Figs. 7 and 8. Here, in the recording device 1 in this embodiment, the ink temperature during printing is controlled to be within the range of 37.5±2.0°C by driving the pump to cause the ink to flow through the metal tube 51 (the ink temperature control range is set to 37.5±2.0°C). 37.5±2.0°C is the temperature range in this embodiment where the ink can maintain a viscosity appropriate for printing. In the following description, the same contents as those in the previous embodiment will be omitted as appropriate.

[0046] <Ink temperature control during printing> The ink temperature control during printing will be described with reference to FIG. 7. Since ink is consumed during printing, it is necessary to supply ink to the recording head 2. Therefore, as shown in FIG. 7, the pump during printing is always driven. During printing, the ink temperature tends to rise due to factors such as ejection from the recording head and the temperature inside the machine. However, the ink temperature may vary depending on the operating conditions of the recording device 1. Therefore, in this embodiment, the first temperature detection means 22 detects the ink temperature just before entering the recording head 2, and the ink temperature control unit 53 controls the temperature adjustment by the ink temperature adjustment means 52 based on the detected ink temperature. In detail, as shown in FIG. 7, cooling is performed in the upper convex part of the 37.5°C line, and heating is performed in the lower convex part. By such ink temperature control, the ink temperature is maintained within the range of 37.5±2.0°C, which is the printable ink temperature range.

[0047] <Temperature control when not printing (when internal temperature is 30.0°C)> Ink temperature control when not printing will be explained with reference to Fig. 8(a) using an example where the internal temperature is 30.0°C. In the graph of Fig. 8(a), the horizontal axis represents time and the vertical axis represents ink temperature, and with respect to the thick line in the figure, the portion up to point A (to the left of point A) represents the change in ink temperature when printing, and the portion after point A (to the right of point A and including point A) represents the change in ink temperature when not printing.

[0048] When printing ends and the printer transitions to a non-printing state and the pump is stopped, the ink temperature drops to 34.0°C (point B), which is the lower limit of the ink temperature control range shown in the figure, because the internal temperature is lower than the ink temperature. After dropping to 34.0°C (point B), the ink temperature rises again to 37.5°C (point C) as the pump is restarted, and then drops to 34.0°C (point D) as the pump is stopped again, and the temperature repeats rising and falling thereafter. In this way, heating is performed when the temperature detected by the first temperature detection means 22 falls to 34.0°C or lower.

[0049] During printing, the ink temperature control range is set to 37.5±2.0°C, and the pump is constantly driven to circulate the ink, resulting in the ink temperature being within the range of 35.5°C to 39.5°C. In contrast, during non-printing, the pump is intermittently driven to circulate the ink, controlling the ink temperature to be within the range of 37.5±3.5°C. As a result, the ink temperature during non-printing is maintained within the range of 34.0°C to 37.5°C. This temperature range of 34.0°C to 37.5°C is closer to the internal temperature (30.0°C) than the ink temperature range during printing, 35.5°C to 39.5°C. Therefore, the ink temperature drops slower than during printing.

[0050] In this way, by setting the ink temperature control range during non-printing so as to include the ink temperature range during printing, it is possible to control the temperature using the one of the two temperature thresholds (i.e., the upper threshold and the lower threshold) that define the ink temperature control range during non-printing, whichever is closer to the internal temperature of the machine. This makes it possible to reduce the amount of pump drive, which contributes to extending the pump's lifespan. Furthermore, by resuming pump drive when the ink temperature is below a specified temperature threshold, it is possible to prevent the ink temperature from deviating significantly from the printable temperature range, and to prevent the time until reprinting can be started from becoming too long.

[0051] <Temperature control when not printing (when internal temperature is 45°C)> Ink temperature control when not printing will be explained with reference to Fig. 8(b) using an example where the internal temperature is 45°C. In the graph of Fig. 8(b), the horizontal axis represents time and the vertical axis represents ink temperature, and with respect to the thick line in the figure, the portion up to point A (to the left of point A) represents the change in ink temperature when printing, and the portion after point A (to the right of point A and including point A) represents the change in ink temperature when not printing.

[0052] When printing ends and the printer transitions to a non-printing state and the pump is stopped, the ink temperature rises to 41.0°C (point B), the upper limit of the ink temperature control range shown in the figure, because the internal temperature is higher than the ink temperature. After rising to 41.0°C (point B), the ink temperature drops again to 37.5°C (point C) as the pump is restarted, and then the pump is stopped again and the ink temperature rises to 41.0°C (point D), and thereafter repeats rising and falling. In this way, cooling is performed when the temperature detected by the first temperature detection means 22 is 41.0°C or higher.

[0053] During printing, the ink temperature control range is set to 37.5±2.0°C, and the pump is constantly driven to circulate the ink, resulting in the ink temperature being within the range of 35.5°C to 39.5°C. In contrast, during non-printing, the pump is driven intermittently to circulate the ink, controlling the ink temperature to be within the range of 37.5±3.5°C. As a result, the ink temperature during non-printing is maintained within the range of 37.5°C to 41.0°C. This temperature range of 37.5°C to 41.0°C is closer to the internal temperature (45°C) than the printing temperature range of 35.5°C to 39.5°C. Therefore, the rate at which the temperature rises is slower than during printing.

[0054] In this manner, in this embodiment, by setting an ink temperature control range during non-printing so as to include the ink temperature range during printing, it is possible to perform temperature control using the one of the two temperature thresholds (i.e., the upper threshold and the lower threshold) that define the ink temperature control range that is closer to the internal temperature of the machine. This makes it possible to reduce the amount of pump drive, which contributes to extending the pump's life. Furthermore, by resuming pump drive when the ink temperature is equal to or higher than a predetermined temperature threshold, it is possible to prevent the ink temperature from deviating significantly from the printable temperature range, and to prevent the time until reprinting can be started from becoming too long.

[0055] <Processing flow> The ink temperature control process in this embodiment, specifically, the process of switching the ink temperature control range when transitioning from a non-printing state to a printing state (in other words, the process of using different ink temperature control ranges during printing and non-printing) will be described below with reference to Fig. 9. Note that each process shown in Fig. 9 is executed by the CPU of the ink temperature control unit 53.

[0056] After printing is completed, in S901, the ink temperature control range during non-printing is set to 37.5±3.5° C. for the ink temperature adjustment means 52. As a result, during subsequent non-printing states, the ink temperature is controlled to always be within the range of 37.5±3.5° C.

[0057] In S902, it is determined whether a print job has been received. If the determination result in this step is true, the process proceeds to S903. On the other hand, if the determination result in this step is false, the process returns to S901. After that, loop processing is performed until a print job is received.

[0058] In S903, 37.5±2.0° C. is set as the ink temperature control range during printing for the ink temperature adjustment means 52. As a result, in the subsequent printing state, the ink temperature is controlled so as to always fall within the range of 37.5±2.0° C.

[0059] Note that, although an embodiment has been described in which the ink temperature control range during printing is set to 37.5°C±2.0°C in S903, the ink temperature control range during printing is not limited to this, and other ranges may be adopted. Also, instead of setting a temperature range such as 37.5°C±2.0°C for the ink temperature adjustment means 52, a predetermined temperature (one value) may be set. Furthermore, the temperature range or temperature set in S903 may be variable so that it can be changed midway.

[0060] Similarly, the ink temperature during non-printing set in S901 is not limited to 37.5±3.5° C., and other temperature ranges or temperatures may be used.

[0061] <Effects of this embodiment> As described above, according to this embodiment, by making the non-operation time of the pump longer when not printing than when printing, the amount of pump operation can be reduced compared to when the pump is controlled in the same way when not printing, and the pump life can be extended. Also, in a non-printing state, if the ink temperature is equal to or higher than a predetermined temperature threshold or equal to or lower than a predetermined temperature threshold, the pump operation is resumed, thereby preventing the ink temperature from deviating significantly from the printable temperature range and preventing the time until reprinting can be started from becoming long.

[0062] Therefore, it is possible to both suppress the rate at which parts deteriorate and shorten the time until reprinting can begin.

[0063] [Third embodiment] Hereinafter, ink temperature control during non-printing in the third embodiment will be described with reference to Fig. 10. In the following description, content that is the same as in the previous embodiment will be omitted as appropriate.

[0064] <Temperature control when not printing (when internal temperature is 30.0°C)> Ink temperature control when not printing will be explained with reference to Fig. 10(a) using an example where the internal temperature is 30.0°C. In the graph in Fig. 10(a), the horizontal axis represents time and the vertical axis represents ink temperature, and with respect to the thick line in the figure, the portion up to point A (to the left of point A) represents the change in ink temperature when printing, and the portion after point A (to the right of point A and including point A) represents the change in ink temperature when not printing.

[0065] When printing is completed and the printer transitions to a non-printing state and the pump is stopped, the ink temperature drops to 34.0°C (point B), which is the lower limit of the ink temperature control range shown in the figure, because the internal temperature is lower than the ink temperature. After dropping to 34.0°C (point B), the ink temperature rises to 39.5°C (point C) as the pump is restarted, and then drops to 34.0°C (point D) as the pump is stopped again, and thereafter repeats rising and falling. Thus, in this embodiment, the target value of the ink temperature control when the ink temperature drops below the lower limit of the printable temperature range is set to 39.5°C, which is the upper limit of the printable temperature range. This allows the ink temperature to drop for a longer period of time than in the second embodiment (see FIG. 8(a)), and therefore the amount of pump driving can be reduced more than in the second embodiment. Also, since the period during which the ink temperature is within the printable temperature range is longer than in the second embodiment, the time until reprinting can be started can be generally shorter than in the second embodiment, which is advantageous for starting reprinting.

[0066] <Temperature control when not printing (when internal temperature is 45.0°C)> Ink temperature control when not printing will be explained using Fig. 10(b) as an example when the internal temperature is 45.0°C. In the graph in Fig. 10(b), the horizontal axis represents time and the vertical axis represents ink temperature, and with respect to the thick line in the figure, the portion up to point A (to the left of point A) represents the change in ink temperature when printing, and the portion after point A (to the right of point A and including point A) represents the change in ink temperature when not printing.

[0067] When printing is completed and the printer is switched to a non-printing state and the driving of the pump is stopped, the ink temperature rises to 41.0°C (point B), which is the upper limit of the ink temperature control range shown in the figure, because the internal temperature is higher than the ink temperature. After the ink temperature rises to 41.0°C (point B), the pump driving is resumed and the ink temperature falls to 35.5°C (point C), and then the pump driving is stopped again and the ink temperature rises to 41.0°C (point D), and thereafter the temperature repeats falling and rising. In this manner, in this embodiment, the target value of the ink temperature control when the ink temperature rises beyond the upper limit of the printable temperature range is set to 35.5°C, which is the lower limit of the printable temperature range. This allows the ink temperature to rise for a longer time than in the second embodiment (see FIG. 8(b)), and the rise time can be lengthened, so that the pump driving amount can be reduced more than in the second embodiment. In addition, the period during which the ink temperature falls within the printable temperature range is longer than in the second embodiment, so that the time until reprinting can be started can be generally shortened compared to the second embodiment, which is advantageous in starting reprinting.

[0068] <Effects of this embodiment> According to this embodiment, when the ink temperature falls below the lower threshold value of the printable temperature range (35.5°C), the target value for ink temperature control is set to 39.5°C, which is the lower limit of the printable temperature range (see FIG. 8(a)). Also, when the ink temperature rises above the upper threshold value of the printable temperature range (39.5°C), the target value for ink temperature control is set to 35.5°C, which is the lower limit of the printable temperature range (see FIG. 8(b)).

[0069] As a result, the ink temperature rise time or fall time can be made longer than in the second embodiment, and the amount of pump drive can be reduced compared to the second embodiment.

[0070] Also, since the period during which the ink temperature is within the printable temperature range is longer than in the second embodiment, the time until reprinting can be started can be generally shorter than in the second embodiment, which is advantageous for starting reprinting.

[0071] In this embodiment, the ink temperature control range during non-printing is set to 34.0° C. to 41.0° C., but a temperature range other than this may be used, and the set temperature range may be variable.

[0072] [Fourth embodiment] The ink temperature control process in this embodiment will be described below with reference to Fig. 11. In the following description, details that are the same as those in the previous embodiment will be omitted as appropriate.

[0073] The processes shown in FIG. 11 are executed by the CPU of the ink temperature control unit 53.

[0074] In S1101, it is determined whether one hour has passed since the end of the print process without receiving a print job. If the determination result in this step is true, the process proceeds to S1102. On the other hand, if the determination result in this step is false, the process returns to S1101. After that, the loop process is repeated until one hour has passed.

[0075] In S1102, 37.5±3.5° C. is set as the ink temperature control range during non-printing in the ink temperature adjustment means 52. As a result, during subsequent non-printing states, the ink temperature is controlled to always be within the range of 37.5±3.5° C.

[0076] In S1103, it is determined whether a print job has been received. If the determination result in this step is true, the process proceeds to S1104. On the other hand, if the determination result in this step is false, the process returns to S1102. After that, loop processing is performed until a print job is received.

[0077] In S1104, 37.5±2.0° C. is set as the ink temperature control range during printing for the ink temperature adjustment means 52. As a result, in the subsequent printing state, the ink temperature is controlled so as to always fall within the range of 37.5±2.0° C.

[0078] <Effects of this embodiment> As described above, in this embodiment, a one-hour waiting time is provided after printing is completed (S1101). This allows printing to be performed without performing ink temperature adjustment when reprinting within one hour immediately after printing is completed. Although one hour is used as the waiting time in this embodiment, other times may be used. The user can selectively set a time longer or shorter than this.

[0079] [Other embodiments] In the above embodiment, the sub-tank 11 and the ink filter 60 are disposed in the ink circulation path, and the second temperature detection means 32 is disposed near the ink circulation path (see FIG. 3), but these parts are not essential components. The object of the present invention can be achieved even without the sub-tank 11, the ink filter 60, and the second temperature detection means 32.

[0080] In addition, regarding the configuration of the heat exchange means 50, the heat exchange means 50 does not necessarily have to have the metal tube 51, and may be a wide variety of heat exchange means, for example, by using a plate type. The circulation pump is not limited to a tube pump type, and other types of circulation pumps may be used.

[0081] In addition, a "changed mode" in which the temperature or temperature range set for printing and non-printing can be changed later, and a "no change mode" in which it cannot be changed later may be provided, allowing the user to select either mode.

[0082] The present invention can also be realized by a process in which a program for realizing one or more functions of the above-mentioned embodiments is supplied to a system or device via a network or a storage medium, and one or more processors in a computer of the system or device read and execute the program. The present invention can also be realized by a circuit (e.g., ASIC) for realizing one or more functions. [Explanation of symbols]

[0083] 1 Recording device 2 Recording head 50 Heat exchange means 52 Ink temperature adjustment means 53 Ink temperature control unit

Claims

1. A recording head that ejects ink to record; an ink path including the recording head and through which the ink flows; a heat exchange means for cooling or heating the ink in the ink path; an adjusting means for adjusting a temperature of the ink by using the heat exchange means; a pump for supplying the ink to the recording head through the ink path; a control means for controlling the adjusting means and the pump; A recording device having the control means controls the adjustment means and the pump so that the temperature of the ink reaches a target value set in a printing state, and further controls the adjustment means and the pump so that the temperature of the ink is maintained within a first temperature range set in the adjustment means in a non-printing state; the target value is within the first temperature range; the first temperature range includes both a temperature range in the printing state and a temperature range in the non-printing state, the target value is included in a second temperature range having a predetermined temperature width with a predetermined temperature as a center temperature, the second temperature range being narrower than the first temperature range, when the temperature of the ink reaches an upper limit or a lower limit of the first temperature range in the non-printing state and the driving of the pump is stopped, the driving of the pump after restart is continued until the temperature of the ink exceeds a boundary value of the second temperature range and reaches at least one value of the second temperature range. A recording apparatus comprising:

2. A tank in which the ink is stored Further comprising: The ink path is provided so that ink circulates, the tank, the heat exchange means, the pump, and the recording head are disposed in the ink path through which the ink circulates; The ink that is not ejected from the recording head returns to the tank.

2. The recording apparatus according to claim 1,

3. the control means stops driving the pump when the printing state is transitioned to the non-printing state.

3. The recording apparatus according to claim 2.

4. when the temperature of the ink reaches an upper limit or a lower limit of the first temperature range in the non-printing state, driving of the pump is resumed; 4. The recording apparatus according to claim 3.

5. The pump is continued to be driven until the temperature of the ink reaches the predetermined temperature. When the temperature of the ink reaches the predetermined temperature, the driving of the pump is stopped again.

5. The recording apparatus according to claim 4.

6. when the temperature of the ink reaches a lower limit of the first temperature range in the non-printing state, the driving of the pump after restart is continued until the temperature of the ink reaches an upper limit of the second temperature range; When the temperature of the ink reaches the upper limit of the second temperature range, the driving of the pump is stopped again.

5. The recording apparatus according to claim 4.

7. when the temperature of the ink reaches an upper limit of the first temperature range in the non-printing state, the driving of the pump after restart is continued until the temperature of the ink reaches a lower limit of the second temperature range; When the temperature of the ink reaches the lower limit of the second temperature range, the operation of the pump is stopped again.

5. The recording apparatus according to claim 4.

8. if no print job is received for a predetermined time in the printing state, the printing state transitions to the non-printing state.

8. The recording apparatus according to claim 2, wherein the recording apparatus comprises:

9. The ink supply device further includes a detection unit disposed in the ink path for detecting a temperature of the ink, The control means performs control based on the temperature detected by the detection means.

9. The recording apparatus according to claim 2, wherein the recording apparatus comprises:

10. the heat exchange means and the detection means are disposed upstream of the recording head in a direction in which the ink circulates, The detection means is disposed immediately before the recording head.

10. The recording apparatus according to claim 9.

11. A recording head that ejects ink to record; an ink path including the recording head and through which the ink flows; a heat exchange means for cooling or heating the ink in the ink path; an adjusting means for adjusting a temperature of the ink by using the heat exchange means; a pump for supplying the ink to the recording head through the ink path; a control means for controlling the adjusting means and the pump; A method for controlling a recording device comprising: a step of controlling the adjusting means and the pump so that the temperature of the ink reaches a target value set in a printing state; a step of controlling the adjusting means and the pump so as to maintain the temperature of the ink within a first temperature range set in the adjusting means in a non-printing state; having the target value is within the first temperature range; the first temperature range includes both a temperature range in the printing state and a temperature range in the non-printing state, the target value is included in a second temperature range having a predetermined temperature width with a predetermined temperature as a center temperature, the second temperature range being narrower than the first temperature range, when the temperature of the ink reaches an upper limit or a lower limit of the first temperature range in the non-printing state and the driving of the pump is stopped, the driving of the pump after restart is continued until the temperature of the ink exceeds a boundary value of the second temperature range and reaches at least one value of the second temperature range. A control method comprising:

12. A program for causing a computer to execute the method according to claim 11.

13. A recording head that ejects ink to record; an ink path including the recording head and through which the ink flows; a heat exchange means for cooling or heating the ink in the ink path; an adjusting means for adjusting a temperature of the ink by using the heat exchange means; a pump for supplying the ink to the recording head through the ink path; a control means for controlling the adjusting means and the pump; A recording device having The control means controls the ink temperature to reach a target value set in a printing state. and controlling the adjusting means and the pump in a non-printing state. and controlling the adjusting means and the pump so as to maintain the temperature of the ink within a first temperature range. death, the target value is within the first temperature range; the target value is included in a second temperature range having a predetermined temperature width with a predetermined temperature as a center temperature, the second temperature range being narrower than the first temperature range, when the temperature of the ink reaches a lower limit of the first temperature range in the non-printing state and the driving of the pump is stopped, the driving of the pump after restart is continued until the temperature of the ink reaches an upper limit of the second temperature range. A recording apparatus comprising:

14. the control means stops driving the pump when the printing state is transitioned to the non-printing state.

14. Recording device according to independent claim 13.

15. When the temperature of the ink reaches the upper limit of the second temperature range, the driving of the pump is stopped again.

15. The recording apparatus according to claim 14.

16. A recording head that ejects ink to record; an ink path including the recording head and through which the ink flows; a heat exchange means for cooling or heating the ink in the ink path; an adjusting means for adjusting a temperature of the ink by using the heat exchange means; a pump for supplying the ink to the recording head through the ink path; a control means for controlling the adjusting means and the pump; A recording device having The control means controls the ink temperature to reach a target value set in a printing state. and controlling the adjusting means and the pump in a non-printing state. and controlling the adjusting means and the pump so as to maintain the temperature of the ink within a first temperature range. death, the target value is within the first temperature range; the target value is included in a second temperature range having a predetermined temperature width with a predetermined temperature as a center temperature, the second temperature range being narrower than the first temperature range, when the temperature of the ink reaches an upper limit of the first temperature range in the non-printing state and the driving of the pump is stopped, the driving of the pump after restart is continued until the temperature of the ink reaches a lower limit of the second temperature range. A recording apparatus comprising:

17. the control means stops driving the pump when the printing state is transitioned to the non-printing state.

17. A recording device according to independent claim 16.

18. When the temperature of the ink reaches the lower limit of the second temperature range, the operation of the pump is stopped again.

20. Recording device according to independent claim 17.

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