JP2016007773A - Image formation device, control method of the same, and program - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image formation device which controls a heater and a drier of a medium on the basis of a detected ink temperature and thereby provides uniform image quality in any situation.SOLUTION: An image formation device includes at least one of heating means which heats a recording medium on which images are formed by droplets and drying means which dries the recording medium. The image formation device includes: detection means which detects a temperature of the droplets; and control means which controls at least one of the heating means and the drying means on the basis of the temperature of the droplets which is detected by the detection means.

Description

  The present invention relates to an image forming apparatus, a control method for the image forming apparatus, and a program.

  In general, a printer, a facsimile, a copy, a plotter, or an image forming apparatus that combines a plurality of these functions includes, for example, a recording head composed of a liquid discharge head that discharges liquid droplets of a recording liquid (liquid). A medium (hereinafter also referred to as “paper”. However, the material is not limited, and a recording medium, a recording medium, a transfer material, recording paper, and the like are also used synonymously) is transported using a liquid ejection device. However, there is a type in which a recording liquid (hereinafter also referred to as ink) as a liquid is attached to a sheet to form an image (also referred to as recording, printing, printing, or printing).

  The image forming apparatus means an apparatus that forms an image by discharging liquid onto a medium such as paper, thread, fiber, fabric, leather, metal, plastic, glass, wood, ceramics, and the like. In addition to giving an image having a meaning such as a character or a figure to the medium, it also means giving an image having no meaning such as a pattern to the medium. The liquid is not limited to recording liquid and ink, and is not particularly limited as long as it becomes a fluid when ejected. Further, the liquid discharge apparatus means an apparatus that discharges liquid from a liquid discharge head, and is not limited to an apparatus that performs image formation.

  Further, as an image forming apparatus including a liquid discharge head, a serial type image recording apparatus that performs recording by mounting the head on a carriage and moving the head in a main scanning direction orthogonal to the paper feeding direction, and substantially the entire width of the recording area. There is a line-type image recording apparatus using a line-type head in which a plurality of discharge ports (nozzles) for discharging droplets are arranged. Furthermore, liquid discharge heads are roughly classified into several types depending on the type of actuator means for discharging ink droplets (recording liquid).

  For example, a part of the wall of the liquid chamber is made into a thin diaphragm, and a piezoelectric element as an electromechanical conversion element is arranged correspondingly, and the diaphragm is deformed by deformation of the piezoelectric element that occurs when voltage is applied. In general, a piezo-type device that changes the pressure in the pressurized liquid chamber and ejects ink droplets is well known. A bubble jet (registered trademark) type in which a heating element is disposed in the liquid chamber, bubbles are generated by heating the heating element by energization, and ink droplets are ejected by the pressure of the bubbles is generally well known. . Furthermore, an electrostatic force generated by applying an electric field between the diaphragm and the electrode, comprising a diaphragm that forms a wall surface of the liquid chamber and an individual electrode outside the liquid chamber that is disposed to face the diaphragm. There has also been proposed an electrostatic type in which an ink droplet is ejected from a nozzle by changing the pressure / volume in the liquid chamber by deforming the diaphragm.

  In recent years, ink jet printers capable of printing on non-penetrating media used in the sign graphics market have been developed. As the image forming technique, a heating and drying method is adopted. In such a system, the conventional heating and drying set temperatures are often provided as standard temperature profiles corresponding to various media and image forming modes.

  Patent Document 1 aims to provide a paper heating device that is less prone to wrinkling when warming paper, and detects the temperature or humidity near the paper and controls the temperature by comparing with data stored in advance. A paper heating apparatus is disclosed. That is, it describes that the temperature near the paper is fed back to control the set temperature for heating and drying.

  However, in the past, much consideration has not been given to places that depend on user usage, such as continuous printing. In particular, if the printing state is continued for a long time, the temperature of the ejected ink becomes high, and there is a possibility that a defect may occur in the image with a standard temperature profile, and there is a problem that a desired image cannot be obtained. .

  In the invention described in Patent Document 1, the temperature near the paper is fed back to control the set temperature for heating and drying. However, as described above, the ink temperature becomes high, and an image is displayed with a standard temperature profile. The problem that a desired image cannot be obtained has not been solved.

  Therefore, the present invention has been made in view of the above-described problems of the prior art, and is uniform in any situation by controlling the heating device or the drying device of the medium based on the detected ink temperature. An object of the present invention is to provide an image forming apparatus capable of providing image quality.

  In order to solve the above problems, an image forming apparatus according to the present invention includes at least one of a heating unit that heats a recording medium on which an image is formed by droplets and a drying unit that dries the recording medium. An apparatus for detecting the temperature of the droplet, and a control unit for controlling at least one of the heating unit and the drying unit based on the temperature of the droplet detected by the detection unit It is characterized by including these.

  According to the present invention, an image forming apparatus capable of providing uniform image quality in any situation can be obtained by controlling the heating device or the drying device of the medium based on the detected ink temperature. .

FIG. 2 is a cross-sectional view along the longitudinal direction of a liquid chamber of an ink jet head of an ink jet printer that is an example of an image forming apparatus according to the present embodiment. FIG. 2 is a cross-sectional view taken along the lateral direction of the liquid chamber of an ink jet head of an ink jet printer that is an example of the image forming apparatus according to the present embodiment. FIG. 2 is a schematic block diagram illustrating a main part of a control unit of the image forming apparatus according to the present embodiment. FIG. 3 is a diagram illustrating an example of a print control unit and a head driver among the main parts of a control unit of the image forming apparatus according to the present embodiment. FIG. 3 is a main view of the liquid ejection head of the image forming apparatus according to the present embodiment viewed from the short side direction. FIG. 3 is a main view of the liquid ejection head of the image forming apparatus according to the present embodiment viewed from the longitudinal direction. FIG. 6 is a diagram illustrating a case where an ink temperature detection unit is present in the liquid ejection head of the image forming apparatus according to the present embodiment. FIG. 6 is a diagram illustrating a case where an ink temperature detection unit exists outside the liquid ejection head of the image forming apparatus according to the present embodiment. FIG. 5 is a diagram illustrating an arrangement example of a common liquid chamber and an ink temperature detection unit of the image forming apparatus according to the present embodiment. In the image forming apparatus according to the present embodiment, it is a diagram illustrating a flow until the ink temperature is detected and the heating or drying temperature is controlled. FIG. 6 is a diagram illustrating a heater setting temperature table with respect to ink temperature in the image forming apparatus according to the present embodiment. In the image forming apparatus according to the present embodiment, it is a diagram for explaining the relationship between the heater temperature and the image quality when the ink temperature is different. FIG. 4 is a diagram illustrating a relationship among ink temperature, media temperature, and image density in the image forming apparatus. In the image forming apparatus, it is a diagram for explaining the relationship between the presence or absence of heating of the head, the heater temperature, and the dot diameter.

  The present invention relates to an image forming apparatus including a heating unit or a drying unit, a control method for the image forming apparatus, and a program, and is characterized by controlling the heating unit or the drying unit based on a detected ink temperature. .

  Hereinafter, embodiments for carrying out the present invention will be described in detail with reference to the drawings. In addition, in each figure, the same code | symbol is attached | subjected to the part which is the same or it corresponds, The duplication description is simplified thru | or abbreviate | omitted suitably.

  First, the basic configuration of the inkjet head according to the present embodiment will be described with reference to FIGS. 1 and 2. FIG. 1 is a cross-sectional view along the longitudinal direction of a liquid chamber of an ink jet head of an ink jet printer which is an example of an image forming apparatus according to the present embodiment. FIG. 2 is a cross-sectional view of the ink jet head of the ink jet printer that is an example of the image forming apparatus according to the present embodiment along the short direction of the liquid chamber.

  This ink jet head includes a frame 1 in which an engraving that forms an ink supply port (not shown) and a common liquid chamber 1-2 is formed. Further, the flow path plate 2 is provided with a engraving to be a fluid resistance part 2-1 and a pressurized liquid chamber 2-2 and a communication port (liquid introduction part) 2-3 communicating with the nozzle 3-1.

  Furthermore, the nozzle plate which forms the nozzle 3-1, and the diaphragm 6 which has the island-shaped convex part 6-1, the diaphragm part 6-2, and the ink inflow port 6-3 are provided. A laminated piezoelectric element 5 joined to the vibration plate 6 via an adhesive layer and a base 4 to which the laminated piezoelectric element 5 is fixed are provided.

  The base 4 is made of a barium titanate ceramic, and the laminated piezoelectric elements 5 are arranged in two rows and joined. The laminated piezoelectric element 5 is composed of a lead zirconate titanate (PZT) piezoelectric layer 5-1 having a thickness of 10 to 50 μm / layer and an internal electrode made of silver / palladium (AgPd) having a thickness of several μm / layer. Layers 5-2 are alternately stacked.

  The internal electrode layer 5-2 is connected to the individual electrode 5-3 at both ends. The laminated piezoelectric element 5 is divided into comb teeth by half-cut dicing, and every other one is used as a drive unit 5-5 and a support unit 5-6 (non-drive unit). The laminated piezoelectric element 5 is composed of a lead zirconate titanate (PZT) piezoelectric layer 5-1 having a thickness of 10 to 50 μm / layer and an internal electrode made of silver / palladium (AgPd) having a thickness of several μm / layer. Layers 5-2 are alternately stacked. The internal electrode layers 5-2 are alternately electrically connected to the individual electrodes 5-3 and the common electrode 5-4 on the end face electrode (external electrode) on the end face.

  In addition, the inkjet head of the present embodiment is configured to use the laminated piezoelectric element 5 of the d33 method that is displacement in the thickness direction, and the pressurized liquid chamber 2-2 is contracted and expanded by expansion and contraction of the laminated piezoelectric element 5. It is like that. When the drive signal is applied to the multilayer piezoelectric element 5 and charging is performed, the multilayer piezoelectric element 5 expands, and when the charge charged in the multilayer piezoelectric element 5 is discharged, the multilayer piezoelectric element 5 contracts in the opposite direction.

  An FPC (Flexible Printed Circuits) 7 is soldered to the individual electrodes 5-3 of the drive unit. In addition, the common electrode 5-4 is provided with an electrode layer at the end of the multilayer piezoelectric element 5, and is joined to the ground electrode of the FPC 7. A driver IC (Integrated Circuit) (not shown) is mounted on the FPC 7 to control application of a drive voltage to the drive unit 5-5.

  The diaphragm 6 includes a thin-film diaphragm portion 6-2 and an island-shaped convex portion (island portion) 6 that joins the laminated piezoelectric element 5 serving as the driving portion 5-5 formed at the center portion of the diaphragm portion 6-2. −1. In addition, the diaphragm 6 is formed by stacking two layers of Ni plating films formed by electroforming with a thick film portion including a beam joined to the support portion and an opening serving as an ink inflow port 6-3.

  The flow path plate 2 uses a silicon single crystal substrate and is engraved as a fluid resistance portion 2-1, a pressurized liquid chamber 2-2, a liquid introduction portion 2-3, and a communication port 2- The through hole to be 4 was patterned by an etching method. The portion left by etching becomes a partition wall of the pressurized liquid chamber 2-2.

  The nozzle plate 3 is formed of a metal material, for example, an Ni plating film by an electroforming method, and has a large number of nozzles 3-1 that are fine discharge ports for flying ink droplets. The internal shape (inner shape) of the nozzle 3-1 is formed in a horn shape (may be a substantially cylindrical shape or a substantially frustum shape).

  The ink ejection surface (nozzle surface side) of the nozzle plate 3 is provided with a water repellent treatment layer that has been subjected to a water repellent surface treatment (not shown). The water-repellent treatment layer is provided with a water-repellent treatment film selected according to the physical properties of the ink so as to stabilize the ink droplet shape and flight characteristics and to obtain high-quality image quality. For example, PTFE-Ni eutectoid plating, electrodeposition coating of fluororesin, evaporation coating of evaporative fluororesin (eg fluorinated pitch, etc.), baking after solvent application of silicon resin / fluororesin is there.

  The frame 1 that forms the engraving that becomes the ink supply port and the common liquid chamber 1-2 is made by resin molding. In the ink jet head configured as described above, a drive waveform (pulse voltage of 10 to 50 V) is applied to the drive unit 5-5 according to the recording signal, thereby causing a displacement in the stacking direction in the drive unit 5-5. . Then, the pressurized liquid chamber 2-2 is pressurized through the vibration plate 6 to increase the pressure, and ink droplets are ejected from the nozzle 3-1.

  Thereafter, the ink pressure in the pressurizing liquid chamber 2-2 decreases with the end of ink droplet ejection, and negative pressure is generated in the pressurizing liquid chamber 2-2 due to the inertia of the ink flow and the discharge process of the drive pulse. Then, the process proceeds to the ink filling process. At this time, the ink supplied from the ink tank flows into the common liquid chamber 1-2, passes through the ink inlet 6-3 from the common liquid chamber 1-2, and passes through the liquid introducing portion 2-3 and the fluid resistance portion 2-1. As described above, the pressurized liquid chamber 2-2 is filled.

  The fluid resistance unit 2-1 is effective in damping the residual pressure vibration after ejection, but becomes resistant to the maximum filling (refill) due to surface tension. By appropriately selecting the fluid resistance unit 2-1, the balance between the attenuation of the residual pressure and the refill time can be achieved, and the time (drive period) until the transition to the next ink droplet ejection operation can be shortened.

  Next, the main part of the control unit of the image forming apparatus according to the present embodiment will be described. FIG. 3 is a schematic block diagram illustrating the main part of the control unit of the image forming apparatus according to the present embodiment.

  The control unit 500 controls the entire apparatus. The control unit 500 includes a CPU (Central Processing Unit) 501 that also serves as means for controlling the idle ejection operation according to the present embodiment. Further, a ROM (Read Only Memory) 502 that stores a program executed by the CPU 501 and other fixed data, and a RAM (Random Access Memory) 503 that temporarily stores image data and the like are provided. In addition, a rewritable nonvolatile memory (NVRAM: Non Volatile RAM) 504 is provided to hold data even while the apparatus is powered off. An ASIC (Application Specific Integrated Circuit) 505 that processes input / output signals for controlling various types of signal processing, rearrangement, and the like for image data and other devices is provided.

  In addition, a print control unit 508 including a data transfer unit for driving and controlling the recording head 34 and a drive signal generating unit is provided. Further, a head driver (driver IC) 509 for driving the recording head 34 provided on the carriage 33 side and a main scanning motor 554 for moving and scanning the carriage 33 are provided. In addition, a sub-scanning motor 555 that moves the conveyor belt 51 in a circle and a motor driving unit 510 that drives the maintenance / recovery motor 556 of the maintenance / recovery mechanism are provided. The charging roller 56 includes an AC bias supply unit 511 that supplies an AC (Alternating Current) bias.

  The control unit 500 is connected to an operation panel 514 for inputting and displaying information necessary for the apparatus.

  The control unit 500 includes a host I / F (Interface) 506 for transmitting and receiving data and signals to and from the host side. The data is received by the host I / F 506 from the host 600 side such as an information processing device such as a personal computer, an image reading device such as an image scanner, and an imaging device such as a digital camera via a cable or a network.

Then, the CPU 501 of the control unit 500 reads the print data in the reception buffer included in the host I / F 506 and analyzes it. The ASIC 505 performs necessary image processing, data rearrangement processing, and the like, and transfers the image data from the print control unit 508 to the head driver 509.
Note that the generation of dot pattern data for image output is performed by the printer driver 601 on the host 600 side.

  The print control unit 508 transfers the above-described image data as serial data, and outputs a transfer clock, a latch signal, a control signal, and the like necessary for transferring the image data and confirming the transfer to the head driver 509. In addition to this, it includes a D / A converter that performs D / A (Digital / Analog) conversion on the drive pulse pattern data stored in the ROM 502, and a drive signal generation unit including a voltage amplifier, a current amplifier, and the like. It is out. Then, a drive signal composed of one drive pulse or a plurality of drive pulses is output to the head driver 509.

  The head driver 509 applies a drive pulse that constitutes a drive signal provided from the print control unit 508 to a drive element (for example, a piezoelectric element) based on image data corresponding to one row of the recording head 34 input serially. The recording head 34 is driven by applying to the recording head. The driving element generates energy that selectively ejects droplets of the recording head 34. At this time, by selecting a driving pulse constituting the driving signal, for example, dots having different sizes such as large droplets, medium droplets, small droplets, and the like can be distinguished.

  An I / O (Input / Output) unit 513 acquires information from various sensor groups 515 mounted on the apparatus, extracts information necessary for printer control, a print control unit 508, and a motor drive unit 510. And for controlling the AC bias supply unit 511.

  The sensor group 515 includes an optical sensor for detecting the position of the paper, a thermistor for monitoring the temperature in the apparatus, a sensor for monitoring the voltage of the charging belt, an interlock switch for detecting opening and closing of the cover, and the like. is there. The I / O unit 513 can process various sensor information.

  Next, an example of the print control unit and the head driver among the main units of the control unit of the image forming apparatus according to the present embodiment will be described. FIG. 4 is a diagram illustrating an example of the print control unit and the head driver among the main units of the control unit of the image forming apparatus according to the present embodiment.

  As described above, the print control unit 508 includes the drive waveform generation unit 701 and the data transfer unit 702. The drive waveform generation unit 701 generates and outputs a drive waveform (common drive waveform) composed of a plurality of drive pulses (drive signals) within one printing cycle during image formation. Then, a drive waveform (common drive waveform) composed of a plurality of drive pulses (drive signals) is generated and output within one idle discharge period during the idle discharge operation. The data transfer unit 702 outputs 2-bit image data (gradation signals 0 and 1) corresponding to the print image, a clock signal, a latch signal (LAT), and droplet control signals M0 to M3.

  The droplet control signal is a 2-bit signal that instructs each droplet to open and close an analog switch 715 that is a switch unit of the head driver 509 described later. The droplet control signal transitions to the H level (ON) with a waveform to be selected according to the printing cycle of the common drive waveform, and transitions to the L level (OFF) when not selected.

  The head driver 509 includes a shift register 711 that inputs a transfer clock (shift clock) from the data transfer unit 702 and serial image data (gradation data: 2 bits / 1 channel (1 nozzle)). Further, a latch circuit 712 for latching each resist value of the shift register 711 by a latch signal, and a decoder 713 for decoding the gradation data and the droplet control signals M0 to M3 and outputting the result are provided. Furthermore, a level shifter 714 that converts the logic level voltage signal of the decoder 713 to a level at which the analog switch 715 can operate is provided. An analog switch 715 that is turned on / off (opened / closed) by the output of the decoder 713 given through the level shifter 714 is provided.

  The analog switch 715 is connected to the selection electrode (individual electrode) 5-3 of each piezoelectric element 121, and the common drive waveform from the drive waveform generation unit 701 is input thereto. Therefore, the analog switch 715 is turned on in accordance with the result of decoding the serially transferred image data (gradation data) and the droplet control signals M0 to M3 by the decoder 713. As a result, a required drive signal constituting the common drive waveform is passed (selected) and applied to the piezoelectric element 121.

  Next, the configuration of the image forming apparatus including the liquid ejection head according to the present embodiment will be described. FIG. 5 is a main view of the liquid discharge head of the image forming apparatus according to the present embodiment as viewed from the short side direction. FIG. 6 is a main view seen from the longitudinal direction of the liquid discharge head of the image forming apparatus according to the present embodiment.

  First, FIG. 5 will be described. First, the configuration of the recording medium is a roll type in this figure. The recording medium 52 is fed from the roll paper 50 along the conveyance direction indicated by the arrow in FIG. In addition, it is not limited to the roll paper 50, You may use cut paper like a general serial machine.

  Under the recording medium 52, a heater 53 is arranged in three places, a pre-printing portion, a printing region portion, and a post-printing portion. The present embodiment assumes an image forming apparatus to be used in the sign graphics market. Therefore, since a non-penetrable medium is used for the recording medium 52, a heating means such as the heater 53 is necessary.

  Although these heaters 53 are divided into three in FIG. 5, they are not necessarily divided. However, if the temperature is divided into a plurality of parts, the temperature can be controlled in each of them, and there is an advantage that an optimum temperature control profile can be set depending on the printing method.

  Further, in addition to heating from the bottom of the recording medium 52, a drying fan heater 54 is provided in the post-printing portion. By applying warm air from the drying fan heater 54, the printed matter can be reliably dried. In the print area portion, there is a carriage 55 on which an inkjet head 57 is mounted.

  Next, FIG. 6 will be described. The portion that could not be illustrated in FIG. 5 is the maintenance / recovery mechanism 61 located on the right side of the recording medium 52. The maintenance / recovery mechanism 61 is for maintaining and recovering the nozzles of the ink-jet head 57. When printing is not performed, each ink-jet head 57 is capped by the nozzle cap 62.

  In addition, when a problem such as nozzle clogging occurs, the nozzle is recovered by empty discharge to recover the nozzle, or the nozzle surface overflowing with ink is wiped by the wiper 64 for nozzle maintenance. Although not described in FIG. 5, the carriage 55 is configured to reciprocate in a direction orthogonal to the paper transport direction.

  Next, a method for detecting the ink temperature of the image forming apparatus according to the present embodiment will be described with reference to FIGS. FIG. 7 is a diagram illustrating a case where the ink temperature detection unit is present in the liquid ejection head of the image forming apparatus according to the present embodiment. FIG. 8 is a diagram illustrating a case where the ink temperature detection unit exists outside the liquid ejection head of the image forming apparatus according to the present embodiment.

  FIG. 7 shows a part of the liquid discharge head. The ink temperature detecting means 7-1 is arranged inside (inside the housing) the housing 7-2 of the liquid ejection head. The ink temperature detection means 7-1 is desirably a highly accurate temperature sensor that can follow the temperature change during ejection, but may be a general-purpose one if cost is taken into consideration. Further, any method may be used for detecting the temperature.

  The ink temperature detection position 7-3 is assumed to be at a position where the temperature of the common liquid chamber 1-2 (FIG. 1) connected to the individual liquid chamber of each nozzle can be detected. In FIG. 7, both the longitudinal direction and the lateral direction of the housing 7-2 of the liquid ejection head are arranged in the center. Here, how the ink temperature detecting means 7-1 detects the temperature of the common liquid chamber 1-2 will be described. FIG. 9 is a diagram illustrating an arrangement example of the common liquid chamber and the ink temperature detection unit of the image forming apparatus according to the present embodiment.

  As shown in FIG. 9, when there are two common liquid chambers 1-2, the ink temperature detecting means 7-1 is arranged at the center position between them. As described above, the ink temperature can be indirectly detected by disposing it in the vicinity of the common liquid chamber 1-2. In addition, by detecting the ink temperature in the vicinity of the common liquid chamber 1-2 serving as a supply source for supplying ink to the individual liquid chambers or individual nozzles, a stable image is output even when the ink temperature changes during printing. It can be done.

  FIG. 8 shows the positional relationship between the housing 8-1 of the liquid ejection head and the ink temperature detection means (infrared radiation thermometer) 8-3. The difference from the embodiment shown in FIG. 7 is that the ink temperature detecting means (infrared radiation thermometer) 8-3 is arranged outside the housing 8-1 of the liquid discharge head (outside the housing). By arranging in this way, the ink temperature is not measured directly, but the ink temperature is grasped by measuring the temperature of the surface of the nozzle plate 8-2.

  Actually, since the ink droplets are ejected at the final arrival point of the liquid ejection head, the ink temperature at the time of ejection can be measured by measuring the temperature of the surface of the nozzle plate 8-2. Is possible. The temperature measuring means on the surface of the nozzle plate 8-2 is a non-contact type. Non-contact temperature measurement is generally performed with an infrared radiation thermometer 8-3, as shown in FIG.

  Infrared radiation energy emitted from the surface of the nozzle plate 8-2 is measured using an infrared sensor 8-4. The infrared radiation thermometer 8-3 is desirably disposed near the maintenance and recovery mechanism 61 described with reference to FIG. By measuring the temperature at the time of empty discharge operation or maintenance operation at the time of printing, the temperature can be measured periodically without causing any trouble during printing, so heating means or drying based on ink temperature It becomes easy to control the means.

  Next, a mechanism for detecting the ink temperature of the image forming apparatus according to the present embodiment and controlling the temperature of the heating unit or the drying unit will be described. FIG. 10 is a diagram illustrating a flow until the ink temperature is detected and the heating or drying temperature is controlled in the image forming apparatus according to the present embodiment.

  In the flow from print job start to print completion shown in FIG. 10, first, (1) after receiving and starting a print job, (2) ink temperature before printing using the method described in FIGS. Is detected. Thereafter, (3) the temperature setting data (table) of the heating means or drying means is referred to, and (4) the temperature of the heating means or drying means is determined. The temperature setting data of the heating means or drying means may be prepared in advance as a table and built in the image forming apparatus.

  Here, the heater temperature setting table for the ink temperature in the image forming apparatus according to the present embodiment will be described. FIG. 11 is a diagram illustrating a heater setting temperature table with respect to ink temperature in the image forming apparatus according to the present embodiment.

  As shown in FIG. 11, a table is prepared in which the heater temperature setting values of the heating unit or the drying unit that make the image quality uniform corresponding to each ink temperature are associated in advance. As a result, even if the ink temperature changes, this table may be referred to and control may be performed so that an appropriate heater temperature setting value is obtained. In the table of FIG. 11, the ink temperature is cut at intervals of 5 ° C. However, when more precise heater temperature control is performed, it is preferable to set the ink temperature finely at intervals of 1 ° C.

  Returning to FIG. 10, the printing conditions are determined through these steps, and (5) actual printing is started. (6) The ink temperature is detected at regular intervals during printing, and the setting value (table) of the heater temperature of the heating means or drying means is referred to, and the temperature of at least one of the heating means or drying means is set to the best setting value as needed. Continue to print while changing to. That is, it is an image in which the steps (3) to (6) are repeatedly executed during printing. By executing printing in this way, the temperature of the heating means or drying means is set according to the ink temperature, so that stable image formation can be performed from the start of printing to the end of printing, and a good quality image Can be provided.

  Next, the relationship between the ink temperature, heater temperature, and image quality of the image forming apparatus according to the present embodiment will be described with reference to FIG. FIG. 12 is a diagram illustrating the relationship between the heater temperature and the image quality when the ink temperatures are different in the image forming apparatus according to the present embodiment.

  In the graph of FIG. 12, the ink temperature is shown for three types of 25 ° C., 35 ° C., and 45 ° C., but is not limited to this temperature. From the evaluation results so far, it has been found that the ink has the best value of image quality depending on the temperature, and the heating temperature or drying temperature at that time also differs. If this characteristic is known in advance, the relationship between the heating temperature or the drying temperature with respect to the ink temperature for maintaining the image quality constant can be grasped. Therefore, as described with reference to FIG. It should be built in as a table.

  In this embodiment, the temperature of the ink is detected, and the heating unit or the drying unit is controlled so that the optimum image quality is obtained at the detected temperature. Therefore, the temperature control of the ink itself is not performed. However, when the set temperature of the heating unit or the drying unit is changed for some reason, the temperature of the ink itself may be controlled so as to obtain an optimum image quality.

  In this case, the table showing the relationship between the ink temperature described in FIG. 11 and the setting temperature of the heating means or drying means for obtaining the optimum image quality, or the heater temperature and image quality when the ink temperature described in FIG. 12 is different. It is possible to obtain stable image quality based on the relationship between

  As described above, in the technique described in Patent Document 1, the temperature and humidity near the paper are detected, and the temperature is controlled by comparing with the data stored in advance. A paper heating device was provided. On the other hand, in the present embodiment, attention is paid to the ink temperature. From the evaluation results so far, it is known that when the ink temperature is different, the temperature of the heating device or the drying device that produces the best image density changes. The results are shown in FIGS. FIG. 13 is a diagram illustrating the relationship between the ink temperature, the media temperature, and the image density in the image forming apparatus. FIG. 14 is a diagram illustrating the relationship between the presence or absence of heating of the head, the heater temperature, and the dot diameter in the image forming apparatus.

  Such a relationship is stored in the image forming apparatus in advance, and the detected ink temperature is used as input data based on information (tables, calculation formulas, etc.) stored in the image forming apparatus. It is an image to control. Thereby, high-quality image formation can be performed stably.

  In addition, each operation | movement of each functional block which comprises the inkjet printer based on this embodiment shown in FIG. 9 can also be made to perform the program on a computer. That is, the CPU 501 in the control unit 500 loads a program stored in a storage medium such as the ROM 502. This is realized by sequentially executing each processing step of the program.

  As described above, in the present invention, at least one of the medium heating device and the drying device is controlled based on the detected ink temperature. As a result, an image forming apparatus, a control method for the image forming apparatus, and a program capable of providing uniform image quality in any situation can be obtained.

  The present invention has been described above by the preferred embodiments of the present invention. While the invention has been described with reference to specific embodiments thereof, various modifications and changes can be made to these embodiments without departing from the broader spirit and scope of the invention as defined in the claims. is there.

DESCRIPTION OF SYMBOLS 1 Frame 1-2 Common liquid chamber 2 Flow path plate 2-1 Fluid resistance part 2-2 Pressurized liquid chamber 2-3 Liquid introduction part 2-4 Communication port 3 Nozzle plate 3-1 Nozzle 4 Base 5 Multilayer piezoelectric element 5-1 Piezoelectric layer 5-2 Internal electrode layer 5-3 Individual electrode 5-4 Common electrode 5-5 Drive part 5-6 Support part 6 Diaphragm 6-1 Island-like convex part (island part)
6-2 Diaphragm section 6-3 Ink inlet 7 FPC
7-1 Ink temperature detection means 7-2, 8-1 Liquid discharge head housing 7-3 Ink temperature detection position 8-2 Nozzle plate 8-3 Ink temperature detection means (infrared radiation thermometer)
8-4 Infrared sensor 33, 55 Carriage 34 Recording head 50 Roll paper 51 Conveying belt 52 Recording medium 53 Heating heater 54 Drying fan heater 56 Charging roller 57 Inkjet head 61 Maintenance recovery mechanism 62 Nozzle cap 63 Empty discharge receiver 64 Wiper 121 Piezoelectric element 500 Control unit 501 CPU
502 ROM
503 RAM
504 NVRAM
505 ASIC
506 Host I / F
508 Print control unit 509 Head driver 510 Motor drive unit 511 AC bias supply unit 513 I / O
514 Operation Panel 515 Sensor Group 554 Main Scan Motor 555 Sub Scan Motor 556 Maintenance Recovery Motor 600 Host 601 Printer Driver 701 Drive Waveform Generation Unit 702 Data Transfer Unit 711 Shift Register 712 Latch Circuit 713 Decoder 714 Level Shifter 715 Analog Switch

JP 05-031891 A

Claims (10)

An image forming apparatus including at least one of a heating unit that heats a recording medium on which an image is formed by droplets, and a drying unit that dries the recording medium,
Detecting means for detecting the temperature of the droplet;
Control means for controlling at least one of the heating means or the drying means based on the temperature of the droplet detected by the detection means;
An image forming apparatus comprising:   The detection unit is disposed in a casing of a liquid discharge head that discharges the liquid droplets, and detects a temperature of a liquid droplet in the vicinity of a common liquid chamber that is a supply source of the liquid droplets. The image forming apparatus described in 1.   2. The detection unit is disposed outside a casing of a liquid discharge head that discharges the liquid droplets, and detects a temperature of a liquid droplet on a surface of a nozzle plate that is a final arrival point of the liquid droplets. The image forming apparatus described in 1.   The image forming apparatus according to claim 3, wherein the detection unit detects the temperature of the droplet on the surface of the nozzle plate in a non-contact manner with the surface of the nozzle plate.   The detection means is at least one of an idle ejection operation for recovering the nozzle that ejects the droplets performed while the image is being formed, and a maintenance operation that is performed while the image is not being formed. 5. The image forming apparatus according to claim 1, wherein the temperature of the droplet is detected at a timing of   The temperature of the droplet is associated with a preset value of the heating unit or the drying unit that uniformly forms image quality, and the control unit sets at least one of the heating unit and the drying unit, 6. The image forming apparatus according to claim 1, wherein control is performed so that the set value is associated with the detected temperature of the droplet. The image forming apparatus according to claim 1, wherein the detection unit detects the temperature of the droplet at a predetermined interval while the image is being formed.   The image forming apparatus according to claim 1, wherein the recording medium is a non-penetrable medium. An image forming apparatus control method comprising at least one of a heating unit that heats a recording medium on which an image is formed by droplets, and a drying unit that dries the recording medium,
Detecting the temperature of the droplet;
Controlling at least one of the heating means or the drying means based on the temperature of the droplet detected by the detecting step;
A control method for an image forming apparatus. A computer of an image forming apparatus including at least one of a heating unit that heats a recording medium on which an image is formed by droplets, and a drying unit that dries the recording medium.
A process for detecting the temperature of the droplet;
A process for controlling at least one of the heating means or the drying means based on the temperature of the droplets detected by the detecting process;
A program to realize

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