Image forming apparatus, control method, and program

Abstract

This invention provides an image forming apparatus, control method, and program that enable more accurate detection of anomalies in the image forming unit and correction of the image forming process by reading test charts. [Solution] The image forming apparatus 20 includes a transport unit 21 for transporting a recording medium, an image forming unit 23 for forming an image on the recording medium transported by the transport unit 21, a predetermined influencing factor that affects the deformation of the test chart formed on the recording medium, and a control unit 29 that suppresses deformation with respect to the predetermined influencing factor when the image forming unit 23 forms the test chart.

Description

Technical Field

[0001] The present disclosure relates to an image forming apparatus, a control method, and a program.

Background Art

[0002] Conventionally, image forming apparatuses that form an image on a recording medium have been known. In such an image forming apparatus, in order to detect whether image forming processing is performed correctly, it is common practice to form a test chart on a recording medium and correct the image forming processing in accordance with the reading result of the test chart.

[0003] However, in such correction processing, if the recording medium on which the test chart is formed is deformed, errors occur in the reading result of the test chart and the correction content based on the reading result. Therefore, for example, Patent Document 1 describes that an abnormal noise detection unit detects the presence or absence of abnormal noise caused by deformation of the recording medium on which the test chart is formed, and corrects the correction content based on the detection result.

Prior Art Literature

Patent Literature

[0004]

Patent Document 1

Summary of Invention

Problem to be Solved by the Invention

[0005] However, with the technology described in Patent Document 1, when the deformation amount of the recording medium is very small, there is a possibility that abnormal noise caused by the deformation cannot be detected. Therefore, errors may occur in the reading result of the test chart and the correction content based on the reading result. Furthermore, even if abnormal noise caused by minute deformation can be detected, there is a limit to the correction of correction content based on the detected abnormal noise.

[0006] This disclosure is made in view of the aforementioned circumstances. Its purpose is to provide an image forming apparatus, control method, and program that can more accurately detect anomalies in the image forming unit by reading a test chart and correct the image forming process. [Means for solving the problem]

[0007] To solve the above problems, this disclosure provides an image forming apparatus, A transport unit that transports the recording medium, An image forming unit that forms an image on a recording medium transported by the transport unit, A predetermined influencing factor that affects the deformation of the test chart formed on the recording medium, When the image forming unit forms a test chart, it includes a control unit that suppresses the deformation with respect to the predetermined influencing factors. [Effects of the Invention]

[0008] According to this disclosure, it is possible to detect anomalies in the image forming unit by reading test charts and correct the image forming process with higher accuracy. [Brief explanation of the drawing]

[0009] [Figure 1] This is a side cross-sectional view of each device that makes up the image forming system. [Figure 2] This is a block diagram of an image forming system. [Figure 3] This is a schematic perspective view of the transport drum. [Figure 4] This is a flowchart of the image formation process. [Modes for carrying out the invention]

[0010] Hereinafter, an image forming apparatus according to an embodiment of the present disclosure will be described in detail with reference to the drawings. However, the scope of the invention is not limited to the illustrated examples. In the following description, components having the same function and configuration will be denoted by the same reference numerals, and their descriptions will be omitted.

[0011] [Overall configuration of the image forming system] Figure 1 is a side cross-sectional view showing the schematic configuration of an image forming system 1 comprising an image forming apparatus 20 according to one embodiment of the present disclosure. Figure 2 is a block diagram showing the functional configuration of the image forming system 1. The image forming system 1 comprises a paper feeder 10, an image forming apparatus 20, and a paper discharger 30.

[0012] The image forming system 1, under the control of the control unit 29, forms an image on a recording medium transported in the transport direction from the paper feed device 10 using the image forming apparatus 20, and then discharges the image to the paper discharge device 30.

[0013] Furthermore, the recording medium is not limited to paper; for example, it may be fabric or a plastic film such as polypropylene (PP) or polyethylene terephthalate (PET). In particular, when the recording medium is a plastic film, it is prone to thermal deformation, so the configuration of the present invention works especially well.

[0014] (Paper feeder) The paper feed device 10 comprises a paper feed tray 11 and a paper feed unit 12. The paper feed tray 11 stores the recording medium. The paper feed unit 12 transports the recording medium to the image forming apparatus 20 under the control of the control unit 29.

[0015] Furthermore, the recording medium is not limited to paper such as plain paper or coated paper. Various media can be used as recording media, such as cloth, polyester, and synthetic fibers, as long as the ink deposited on the surface can be fixed.In addition, although Figure 1 illustrates a paper feeder 10 equipped with one paper feed tray 11, it is not limited to this, and a paper feeder 10 equipped with multiple paper feed trays 11, each storing multiple types of recording media, may also be used.

[0016] (Image forming apparatus) The image forming apparatus 20 includes a conveying section 21, a heating section 22, an image forming section 23, a fixing section 24, a reading section 25, a delivery section 26, a communication section 27, an operation display section 28, and a control section 29. The image forming apparatus 20 according to the present embodiment is an inkjet recording apparatus that forms an image by ejecting ink onto a recording medium.

[0017] {Conveying Section} The conveying section 21 conveys a recording medium in the conveying direction. The conveying section 21 includes an A cylinder 211, an A cylinder pressing roller 212, a recording medium pressing roller 213, and a conveying drum 214.

[0018] {Conveying Drum} The conveying drum 214 has a cylindrical shape, and uses its outer peripheral curved surface as a conveying surface, and conveys the recording medium in the conveying direction by rotating around its axis in a state where the recording medium is placed thereon. A perspective view of the conveying drum 214 is shown in FIG. 3. As shown in FIG. 3, the conveying drum 214 includes a claw section 2141 and an air suction section 2142.

[0019] <Claw Section> The claw section 2141 has a plurality of claws arranged in the width direction at predetermined positions on the conveying surface of the conveying drum 214. The claw section 2141 sandwiches and holds the vicinity of one side of the recording medium between itself and the conveying surface of the conveying drum 214. Thereby, the recording medium is placed at a predetermined placement position whose leading end is defined by the claw section 2141.

[0020] <Air Suction Section> The air suction section 2142 includes a plurality of air suction holes provided on the conveying surface of the conveying drum 214, and a suction force generating unit (not shown) (for example, an air pump, a fan, etc.) that generates a suction force for sucking gas into the conveying drum 214 through the air suction holes. That is, the air suction section 2142 sucks the recording medium to align it along the conveying surface of the conveying drum 214 by the suction force generated by air suction through the air suction holes.

[0021] Furthermore, the transport unit 21 is equipped with a drum motor (not shown) that rotates the transport drum 214, and rotates by an angle proportional to the amount of rotation of the drum motor. Note that in Figure 3, a portion of the recording medium is curled up from the transport surface of the transport drum 214, but this is for the purpose of illustrating the air intake hole. Therefore, when the recording medium is transported by the transport drum 214, the entire recording medium is held so as to lie along the transport surface of the transport drum 214.

[0022] {Heating part} The heating unit 22 is an infrared heater or the like, and based on a control signal supplied from the control unit 29, it energizes the infrared heater to generate heat and heat the desired object, thereby homogenizing the image formation conditions related to temperature and suppressing the occurrence of image quality distortions. The heating unit 22 includes a recording medium heating unit 221 and a transport unit heating unit 222.

[0023] <Recording medium heating section, transport section heating section> The recording medium heating unit 221 is provided, for example, in a position opposite the A-body retaining roller 212, with the A-body 211 in between. The recording medium heating unit 221 heats the recording medium being transported by the transport unit 21 to a predetermined temperature. The transport unit heating unit 222 is provided, for example, downstream of the reading unit 25 in the transport direction. The transport unit heating unit 222 heats the transport drum 214 to a predetermined temperature.

[0024] {Image forming unit} The image forming unit 23 forms an image on the recording medium transported by the transport drum 214. The image forming unit 23 is equipped with a plurality of inkjet heads 231, which are arranged so that their nozzle openings are separated from the transport surface of the transport drum 214 by a predetermined distance. The image forming unit 23 supplies drive signals to the inkjet heads 231 at an appropriate timing corresponding to the rotation of the transport drum 214 holding the recording medium. Upon receiving the drive signals, the inkjet heads 231 eject ink onto the recording medium to record an image.

[0025] In this embodiment, four head units, each consisting of multiple inkjet heads 231 corresponding to yellow (Y), magenta (M), cyan (C), and black (K), are mounted on the carriage. The head units are arranged at predetermined intervals in the order of Y, M, C, and K from the upstream side in the transport direction.

[0026] The ink used for recording images by the image forming unit 23 undergoes a phase change between a gel state and a sol state depending on the temperature. A gel state is a solid form, and a sol state is a liquid form. Examples of such ink compositions include those mainly composed of polymerizable compounds and photopolymerization initiators with several percent of a gelling agent added. When a gel-like ink is heated and its temperature is increased, its viscosity begins to decrease significantly once it exceeds the ink's specific solification temperature (for example, around 70°C), and it undergoes a phase change to a sol state. On the other hand, when a sol-like ink is cooled, its viscosity begins to increase significantly once it falls below the ink's specific gelification temperature (for example, around 50°C), and it undergoes a phase change to a gel state.

[0027] The image forming unit 23 includes an ink heating unit (not shown) that heats the ink before it is supplied to the inkjet head 231 and the ink supplied to the inkjet head 231. The inkjet head 231 ejects the ink, which has been heated by the ink heating unit and turned into a sol, from the nozzle N. The ink ejected from the nozzle N and deposited on the recording medium is cooled and rapidly undergoes a phase change to a gel.

[0028] Furthermore, the ink used in this embodiment is a UV (Ultraviolet) ink that has the property of hardening when exposed to ultraviolet light. That is, the ink used in this embodiment is cooled on the recording medium to become gel-like, and then hardened by irradiation with ultraviolet light in the fixing unit 24, thereby fixing it to the recording medium.

[0029] {Fixing part} The fixing unit 24 is located downstream of the image forming unit 23 in the transport direction. The fixing unit 24 fixes the image formed by the image forming unit 23 onto the recording medium. The fixing unit 24 includes, for example, a curing unit 241 which is an energy ray irradiation unit. Specifically, the fixing unit 24 includes a light-emitting unit arranged across the width of the transport surface of the transport drum 214. Under the control of the control unit 29, the light-emitting unit irradiates the transported paper P with energy rays such as ultraviolet light. This hardens and fixes the ink on the recording medium.

[0030] In the above description, the image forming unit 23 is configured to eject UV ink, and therefore the fixing unit 24 is assumed to include a curing unit 241, but this is not limited to this configuration. For example, the fixing unit 24 may include a heating unit 242, such as a heater, which heats the image fixed by the curing unit 241 to perform final fixing. Alternatively, the fixing unit 24 may include a pressurizing unit 243 that pressurizes and smooths the image before fixing by the curing unit 241 or the heating unit 242.

[0031] {Reading section} The reading unit 25 is located downstream of the fixing unit 24 in the transport direction and upstream of the delivery unit 26 in the transport direction. The reading unit 25 is positioned to read, for example, the surface (image forming surface) of the recording medium. The reading unit 25 is, for example, a line sensor. The reading unit 25 acquires reading data of the image formed on the surface of the recording medium by the image forming unit 23. The reading unit 25 transmits the acquired reading data to the control unit 29.

[0032] {Delivery Department} The delivery unit 26 is, for example, a roller and is located downstream of the fixing unit 24 in the transport direction. The delivery unit 26 transports the recording medium, which has passed through the image forming unit 23 and the fixing unit 24 and received from the transport drum 214, to the paper discharge device 30.

[0033] {Communications Department} The communication unit 27 is a communication interface that controls communication operations with external devices. The communication interface may include one or more devices that support various communication protocols, such as LAN boards or LAN cards. Under the control of the control unit 29, the communication unit 27 acquires image data and other data to be recorded from external devices. The communication unit 27 also transmits status information and other data to external devices.

[0034] (Operation display section} The operation display unit 28 displays the status of the image forming apparatus 20, operation menus, etc., in response to control signals from the control unit 29. The operation display unit 28 also receives user input and outputs it to the control unit 29. The operation display unit 28 includes, for example, a liquid crystal display unit in which a touch sensor, which serves as an operation reception means, is superimposed on a display screen, which serves as a display means.

[0035] {control unit} The control unit 29 is a processor that provides overall control over the operation of the image forming system 1. The control unit 29 includes a CPU (Central Processing Unit) 291, RAM (Random Access Memory) 292, ROM (Read Only Memory) 293, and a storage unit 294, etc.

[0036] <CPU> The CPU 291 reads various control programs and setting data stored in the ROM 293, stores them in the RAM 292, and executes the programs to perform various calculations.

[0037] <RAM> RAM292 provides CPU291 with a working memory space and stores temporary data. RAM292 may also include non-volatile memory.

[0038] <ROM> ROM293 stores various control programs and configuration data executed by the CPU291. Alternatively, rewritable non-volatile memory such as flash memory may be used instead of ROM293.

[0039] In particular, the CPU 291 detects abnormalities in the image forming unit 23 by comparing the test chart reading data read by the reading unit 25 with the original image data of the test chart stored in the storage unit 294. If an abnormality is detected, the CPU 291 creates correction information to correct the image forming process based on the detected information and stores it in the RAM 292.

[0040] <Storage part> The storage unit 294 stores print jobs input from an external device via the communication unit 27, as well as image data of the images to be recorded related to those print jobs. For example, an HDD (Hard Disk Drive) can be used as the storage unit 294. Alternatively, DRAM (Dynamic Random Access Memory) or the like may also be used as the storage unit 294.

[0041] (Paper output device) The paper output device 30 holds the recording medium ejected from the image forming apparatus 20 until the user retrieves it. The paper output device 30 is equipped with a plate-shaped paper output tray 31. The paper output device 30 may be equipped with multiple paper output trays 31, similar to the paper feed device 10. In this configuration, the paper output device 30 appropriately controls the storage location of the recording medium in accordance with instructions from the control unit 29 corresponding to the image forming conditions of the image forming apparatus 20.

[0042] [Image Forming Processing] The image formation process performed by the image formation system 1 described above will be explained based on the flowchart in Figure 4. The image formation system 1 executes the image formation process when the control unit 29 receives an image formation instruction from an external device or the like.

[0043] First, the control unit 29 determines whether the image to be formed is a test chart based on the received image formation instruction (step S101). The test chart may be one for detecting defects or bends in the nozzles of the inkjet head 231 (e.g., a nozzle check chart), or one for determining the ejection timing of the inkjet head 231 (e.g., a timing chart). Alternatively, the test chart may be one for detecting the amount of ink ejected by the inkjet head 231 (e.g., a density chart).

[0044] If the object to be formed is not a test chart (step S101; No), in other words, if the object to be formed is a normal image, the control unit 29 forms an image on the recording medium fed from the paper feeder 10 using the image forming apparatus 20 and ejects it to the paper ejector 30 (step S102).

[0045] On the other hand, if the object to be formed is a test chart (step S101; Yes), the control unit 29 performs control for the test chart (step S103; control step).

[0046] During normal image formation, each part of the image forming apparatus 20 is controlled to suppress image quality degradation caused by insufficient ink adhesion. On the other hand, the heat and pressure applied to the recording medium by this control may cause slight deformation of the recording medium. While this deformation does not affect image quality during normal image formation, it can deform the test chart during test chart formation, potentially causing errors in the reading results of the reading unit 25 and the correction content of the image formation process. Therefore, during test chart formation, the control unit 29 controls predetermined influencing factors that affect the deformation of the test chart to suppress such deformation.

[0047] One example of a predetermined influencing factor is the claw portion 2141. When forming a test chart, the control unit 29 controls the number of claw portions 2141 used to hold the recording medium when the recording medium is transported by the transport drum 214 to be different from that used when forming a normal image. The control unit 29 also controls the pressing force of the claw portions 2141 to be different from that used when forming a normal image. Another example of an influencing factor is the intake portion 2142. The control unit 29 controls the suction force of the intake portion 2142 to be different from that used when forming a normal image.

[0048] At this time, the control unit 29 may perform control in a direction that strengthens the degree of contact of the recording medium with the transport surface of the transport drum 214 compared to when an image is formed under normal circumstances (i.e., increasing the number of claws 2141 used, increasing the pressing force of the claws 2141, or increasing the suction force of the suction unit 2142). Alternatively, the control unit 29 may perform control in a direction that weakens the degree of contact of the recording medium with the transport surface of the transport drum 214 compared to when an image is formed under normal circumstances (decreasing the number of claws 2141 used, decreasing the pressing force of the claws 2141, or decreasing the suction force of the suction unit 2142).

[0049] When the control is performed in a direction that strengthens the contact of the recording medium with the transport surface of the transport drum 214, the external force attempting to deform the recording medium will be pressed against the transport surface, thereby suppressing deformation of the recording medium itself and the resulting deformation of the test chart. On the other hand, when the control is performed in a direction that weakens the contact of the recording medium with the transport surface of the transport drum 214, the external force attempting to deform the recording medium can be dispersed, and similarly, deformation of the recording medium itself and the resulting deformation of the test chart can be suppressed.

[0050] Furthermore, a predetermined influencing factor is, for example, the heating unit 22. When forming a test chart, the control unit 29 controls the output of the recording medium heating unit 221 to be different from that when forming a normal image. The control unit 29 also controls the output of the transport unit heating unit 222 to be different from that when forming a normal image.

[0051] At this time, the control unit 29 may control the output of the recording medium heating unit 221 and the transport unit heating unit 222 to either increase or decrease it compared to normal image formation. When the output of the recording medium heating unit 221 and the transport unit heating unit 222 is increased, the heat applied by the recording medium heating unit 221 and the transport unit heating unit 222 can completely deform the recording medium before image formation by the image forming unit 23. Therefore, deformation of the test chart caused by deformation of the recording medium after the formation of the test chart can be suppressed. Also, when the output of the recording medium heating unit 221 and the transport unit heating unit 222 is decreased, deformation of the recording medium due to the heat applied by the recording medium heating unit 221 and the transport unit heating unit 222 is suppressed, and thus deformation of the test chart can be suppressed.

[0052] Furthermore, a predetermined influencing factor is, for example, the fixing unit 24. When forming a test chart, the control unit 29 controls the output of the hardening unit 241, heating unit 242, and pressurizing unit 243 of the fixing unit 24 to be weaker than when forming a normal image. This control suppresses deformation of the test chart caused by deformation of the recording medium after the test chart is formed.

[0053] The control unit 29 controls the influencing factors that affect the deformation of the test chart formed on the recording medium in such a manner, thereby suppressing deformation of the test chart caused by deformation of the recording medium after the test chart is formed. As a result, the test chart can be accurately read by the reading unit 25, and the control unit 29 can detect abnormalities in the image forming unit 23 with higher accuracy and perform corrections with higher accuracy.

[0054] Furthermore, the control of the predetermined influencing factors when forming the test chart as described above may be performed by controlling only one of them, or by combining multiple factors.

[0055] When control is performed for the test chart, the control unit 29 transports the recording medium from the paper feeder 10 to the image forming apparatus 20 and causes the image forming unit 23 to form the test chart (step S104). Once the image forming unit 23 has formed the test chart, the control unit 29 returns the control for the test chart to normal image control (step S105) and terminates the image forming process.

[0056] [Effects of the Embodiment] As described above, the image forming apparatus 20 according to this embodiment includes a transport unit 21 for transporting a recording medium and an image forming unit 23 for forming an image on the recording medium. Furthermore, when the image forming unit 23 forms a test chart, the image forming apparatus 20 includes a predetermined influencing factor that affects the deformation of the test chart formed on the recording medium, and a control unit 29 that suppresses deformation with respect to the predetermined influencing factor. With this configuration, since the deformation of the formed test chart itself is suppressed, abnormality detection by the image forming unit 23 by reading the test chart and correction of the image forming process can be performed with higher accuracy.

[0057] Furthermore, in this embodiment, when forming a test chart, control is performed to suppress deformation, while when forming a normal image excluding the test chart, normal control is performed. Therefore, this configuration does not result in a decrease in the image quality of the normal image excluding the test chart.

[0058] Another possible method to suppress deformation of the test chart is to use a special recording medium that is less prone to deformation only when forming the test chart. However, this configuration would introduce another problem: increased wear and tear. On the other hand, in the configuration of this embodiment, deformation is suppressed by applying different control to the same recording medium used when forming a normal image, so this problem does not arise.

[0059] [Other configurations] In the above, an example of an image forming apparatus 20 according to the embodiments of this disclosure was given in the case of an inkjet recording apparatus that uses ink as a colorant to form an image by an inkjet method, but the invention is not limited to this. For example, the configuration of this disclosure is also applicable when the image forming apparatus 20 is a laser printer that uses toner as a colorant to form an image by an electrophotographic method.

[0060] Furthermore, although the above example illustrates a configuration in which the conveying unit 21 is equipped with a conveying drum 214, the system is not limited to this, and a belt conveying system may also be used.

[0061] Furthermore, in the above example, the control unit 29 determines whether the object to be formed is a test chart or not in step S101 and switches the control of each part accordingly, but the system is not limited to this configuration. For example, it may receive an image formation instruction to form both a test chart and a normal image on a single recording medium. In such a case, it is preferable for the control unit 29 to switch between performing control for the test chart in the area of ​​the recording medium where the test chart is formed, and performing control for the normal image in the area where the normal image is formed.

[0062] Furthermore, the image forming apparatus 20 only needs to include at least a transport unit 21 and an image forming unit 23, and the other components may be separate devices from the image forming apparatus 20. In particular, the reading unit 25 that reads the test chart formed on the recording medium and the control unit 29 that corrects the image forming unit 23 based on the test chart reading data acquired from the reading unit 25 may be separate devices from the image forming apparatus 20.

[0063] Furthermore, while examples of using hard disks and semiconductor non-volatile memory as computer-readable media for the program related to this disclosure have been disclosed above, the disclosure is not limited to these examples. Portable recording media such as CD-ROMs can also be used as other computer-readable media. In addition, carrier waves can be used as a medium for providing the data of the program related to this disclosure via a communication line. [Explanation of symbols]

[0064] 20 Image forming apparatus 21 Conveying section 2141 Claw (influence factor) 2142 Intake section (influencing factors) 22 Heating section (influencing factor) 23 Image forming unit 231 Inkjet Head 24. Fixation area (influencing factors) 241 Hardening Unit 242 Heating Unit 243 Pressurization Unit 25 Reading section 29 Control Unit

Claims

1. A transport unit that transports the recording medium, An image forming unit that forms an image on a recording medium transported by the transport unit, A predetermined influencing factor that affects the deformation of the test chart formed on the recording medium, An image forming apparatus comprising: an image forming unit that forms a test chart, and a control unit that suppresses the deformation with respect to a predetermined influencing factor.

2. It includes a reading unit that reads an image formed on a recording medium, The image forming apparatus according to claim 1, wherein the control unit corrects the image forming conditions of the image forming unit based on the reading result of the reading unit.

3. The predetermined influencing factor includes a heating unit that heats the transport unit and / or the recording medium, The image forming apparatus according to claim 1, wherein the control unit causes the output of the heating unit to differ depending on whether the image forming unit is forming a test chart on the recording medium or whether the image forming unit is forming an image excluding the test chart on the recording medium.

4. The predetermined influencing factor includes a fixing unit that fixes the image formed on the recording medium, The fixing unit includes a curing unit that fixes an image onto a recording medium using energy rays. The image forming apparatus according to claim 1, wherein the control unit suppresses the output of the curing unit when the image forming unit forms a test chart on the recording medium compared to when the image forming unit forms an image excluding the test chart on the recording medium.

5. The predetermined influencing factor includes a fixing unit that fixes the image formed on the recording medium, The fixing unit includes a heating unit that fixes an image onto the recording medium using heat, The image forming apparatus according to claim 1, wherein the control unit suppresses the output of the heating unit when the image forming unit forms a test chart on the recording medium compared to when the image forming unit forms an image excluding the test chart on the recording medium.

6. The predetermined influencing factor includes a fixing unit that fixes the image formed on the recording medium, The fixing unit includes a pressure unit that fixes the image onto the recording medium by pressure, The image forming apparatus according to claim 1, wherein the control unit suppresses the output of the pressurizing unit when the image forming unit forms a test chart on the recording medium more than when the image forming unit forms an image excluding the test chart on the recording medium.

7. The transport unit includes a claw portion for holding the recording medium as the predetermined influencing factor. The image forming apparatus according to claim 1, wherein the control unit makes the pressing force of the claw portion different when the image forming unit forms a test chart on the recording medium and when the image forming unit forms an image excluding the test chart on the recording medium.

8. The transport unit includes a plurality of claws for holding the recording medium, which are predetermined influencing factors. The image forming apparatus according to claim 1, wherein the control unit uses different numbers of the claws when the image forming unit forms a test chart on the recording medium and when the image forming unit forms an image excluding the test chart on the recording medium.

9. The transport unit includes an intake unit that attracts the recording medium to the transport surface as a predetermined influencing factor. The image forming apparatus according to claim 1, wherein the control unit makes the suction force of the intake unit different when the image forming unit forms a test chart on the recording medium and when the image forming unit forms an image excluding the test chart on the recording medium.

10. The image forming apparatus according to any one of claims 1 to 9, wherein the image forming unit comprises an inkjet head that forms an image by ejecting ink.

11. The image forming apparatus according to claim 10, wherein the image forming unit forms a test chart on a recording medium for the control unit to acquire the state of the nozzles of the inkjet head.

12. The image forming apparatus according to claim 10, wherein the image forming unit forms a test chart on a recording medium for the control unit to obtain the ink ejection timing by the inkjet head.

13. The image forming apparatus according to claim 10, wherein the image forming unit forms a test chart on a recording medium for the control unit to obtain the amount of ink ejected by the inkjet head.

14. A transport unit that transports the recording medium, A control method for an image forming apparatus comprising: an image forming unit that forms an image on a recording medium transported by the transport unit; a predetermined influencing factor that affects the deformation of a test chart formed on the recording medium; and a control unit, A control method comprising a control step for suppressing the deformation with respect to a predetermined influencing factor when the image forming unit forms a test chart.

15. A transport unit that transports the recording medium, The computer of the image forming apparatus comprises an image forming unit that forms an image on a recording medium transported by the transport unit, and a predetermined influencing factor that affects the deformation of a test chart formed on the recording medium, A program that causes the image forming unit to function as a control unit that suppresses the deformation with respect to the predetermined influencing factors when forming a test chart.

Images