Image forming apparatus
By controlling the relative speed and pressing force of the cleaning unit, the image forming apparatus stabilizes the cleaning process to prevent head vibrations and ensure effective nozzle maintenance.
Patent Information
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- KONICA MINOLTA INC
- Filing Date
- 2024-11-27
- Publication Date
- 2026-06-08
Smart Images
Figure 2026093163000001_ABST
Abstract
Description
Technical Field
[0001] The present disclosure relates to an image forming apparatus, and more particularly, to a cleaning technique for a print head.
Background Art
[0002] An inkjet type image forming apparatus includes a configuration (hereinafter referred to as a "cleaning unit") for cleaning a print head (hereinafter simply referred to as a "head") that is soiled by ink. At the cleaning start timing and the cleaning end timing of the print head, the head is likely to vibrate. When the head vibrates, the pressing force applied to the head from the cleaning unit changes, and the contact state between the cleaning unit and the head becomes unstable. As a result, the head may not be sufficiently cleaned. Further, when the contact state between the cleaning unit and the head becomes unstable, the cleaning unit behaves differently from normal, and thus scratches may occur around the nozzles of the head. The vibration of the head can be suppressed by setting the pressing force of the cleaning unit low. However, if the pressing force of the cleaning unit is set low, there is a possibility that the head may not be sufficiently cleaned. Therefore, a new cleaning technique for the head is required.
[0003] Regarding head cleaning technology, for example, Japanese Patent Application Publication No. 2009-51030 (Patent Document 1) discloses an inkjet recording apparatus that can suppress ink from scattering inside the apparatus when the wiper blade is restored. The inkjet recording apparatus has a nozzle forming surface on which a plurality of nozzles for ejecting ink are formed, and includes a recording head that ejects ink from the nozzles to record an image on a recording medium that is transported to a position opposite the nozzle forming surface, and an elastic wiper blade that is pressed against the nozzle forming surface of the recording head and wipes the nozzle forming surface, and includes a moving means that moves the recording head and / or wiper blade at a first speed to wipe the nozzle forming surface with the wiper blade, and then moves the wiper blade away from the nozzle forming surface at a second speed which is slower than the first speed (see paragraph
[0006] ). [Prior art documents] [Patent Documents]
[0004] [Patent Document 1] Japanese Patent Publication No. 2009-51030 [Overview of the Initiative] [Problems that the invention aims to solve]
[0005] According to the technology disclosed in Patent Document 1, head vibration is not taken into consideration in the control of the wiper blade. Therefore, the technology disclosed in Patent Document 1 cannot effectively suppress head vibration that may occur during head cleaning. Accordingly, there is a need for technology to suppress head vibration that is likely to occur at the start and end of head cleaning.
[0006] This disclosure is made in view of the above-mentioned background, and in one aspect, its purpose is to provide a technology for suppressing head vibrations that tend to occur at the start and end timings of head cleaning. [Means for solving the problem]
[0007] According to one embodiment, an image forming apparatus is provided. The image forming apparatus comprises a head having nozzles for ejecting ink, a cleaning unit for cleaning the head, and a control unit for controlling the cleaning unit. The cleaning unit is movable relative to the head and is configured to clean the head by moving relative to the head while in contact with the head. The control unit is configured to adjust at least one of the relative speed or pressing force of the cleaning unit with respect to the head based on predetermined operating settings of the cleaning unit. The predetermined operating settings include at least one of information regarding acceleration and information regarding the amount of change in pressing force that can suppress vibrations generated in the head due to cleaning to a predetermined reference value or less.
[0008] In a given scenario, a predetermined operation setting includes at least one of the following: (i) information relating the cleaning performance of the cleaning unit to the head for each relative speed of the cleaning unit, and a value indicating the magnitude of vibrations generated in the head; and (ii) information relating the cleaning performance of the cleaning unit to the head for each pressing force of the cleaning unit, and a value indicating the magnitude of vibrations generated in the head.
[0009] In a given phase, the cleaning unit is configured to move from the cleaning start position to a first point in a first section that includes the cleaning start position of the head to a first point. Adjusting the relative speed of the cleaning unit with respect to the head includes accelerating the relative speed in the first section.
[0010] In a given phase, accelerating the relative velocity in the first section includes gradually increasing the relative velocity.
[0011] In a given phase, the cleaning unit is configured to move from the second point toward the cleaning end position in a second section that includes the section from the head's cleaning end position to the second point. Adjusting the relative speed of the cleaning unit with respect to the head includes reducing the relative speed in the second section.
[0012] In a given phase, reducing the relative speed in the second section includes gradually decreasing the relative speed.
[0013] In a given phase, the cleaning unit is configured to move from the first point to the second point in a third section, which includes the section from the first point to the second point. Adjusting the relative speed of the cleaning unit with respect to the head includes making the acceleration of the relative speed approximately zero in the third section.
[0014] In a given phase, adjusting the pressing force of the cleaning unit against the head includes, in a first section, gradually increasing the pressing force of the cleaning unit against the head.
[0015] In a certain phase, adjusting the pressing force of the cleaning unit against the head includes gradually reducing the pressing force of the cleaning unit against the head in a second section.
[0016] In a certain phase, the control unit controls the cleaning unit so that it moves away from the head once it has passed the area of the head to be cleaned.
[0017] In a certain scenario, the cleaning unit comprises a cleaning member for wiping away dirt from the head and a support member for pressing the cleaning member against the head.
[0018] In a certain phase, the cleaning unit further includes a first roller for feeding out the cleaning material and a second roller for winding up the cleaning material. The cleaning unit uses the first and second rollers to transport the cleaning material in the opposite direction to the direction of movement of the head as viewed from the cleaning unit.
[0019] In certain situations, the cleaning unit is equipped with a roller-shaped elastic body for wiping away dirt from the head.
[0020] In certain situations, the cleaning unit includes a pad-shaped elastic body for wiping away dirt from the head.
[0021] In a given scenario, the print head comprises multiple head modules for ejecting ink. The control unit moves the cleaning unit to clean each of the multiple head modules.
[0022] In a given scenario, the control unit is configured to control the cleaning unit to perform a cleaning process on each of the multiple head modules. Adjusting the relative speed of the cleaning unit with respect to the heads includes adjusting the relative speed of the cleaning unit with respect to each of the multiple head modules.
[0023] According to another embodiment, an image forming apparatus is provided. The image forming apparatus includes a head having nozzles for ejecting ink, a cleaning unit for cleaning the head, and a control unit for controlling the cleaning unit. The cleaning unit is movable relative to the head and is configured to clean the head by moving relative to the head while in contact with the head. The control unit is configured to adjust the relative speed of the cleaning unit with respect to the head based on a predetermined operation setting of the cleaning unit. The predetermined operation setting includes information regarding an acceleration capable of suppressing vibrations generated in the head due to cleaning to be below a predetermined reference value. The control unit is further configured to gradually accelerate the relative speed from the cleaning start timing of the head to the first timing, make the acceleration of the relative speed substantially zero from the first timing to the second timing, and gradually decelerate the relative speed from the second timing to the cleaning end timing of the head.
[0024] According to another embodiment, an image forming apparatus is provided. The image forming apparatus includes a head having nozzles for ejecting ink, a cleaning unit for cleaning the head, and a control unit for controlling the cleaning unit. The cleaning unit is movable relative to the head and is configured to clean the head by moving relative to the head while in contact with the head. The control unit is configured to adjust the pressing force of the cleaning unit with respect to the head based on a predetermined operation setting of the cleaning unit. The predetermined operation setting includes information regarding the amount of change in the pressing force capable of suppressing vibrations generated in the head due to cleaning to be below a predetermined reference value. The control unit is further configured to gradually increase the pressing force from the cleaning start timing of the head to the first timing, make the amount of change in the pressing force substantially zero from the first timing to the second timing, and gradually decrease the pressing force from the second timing to the cleaning end timing of the head.
Advantages of the Invention
[0025] According to an embodiment, it is possible to suppress the vibration of the head that is likely to occur at the head cleaning start and end timings.
[0026] The above and other objects, features, aspects and advantages of this disclosure will become apparent from the following detailed description of the disclosure understood in connection with the accompanying drawings.
Brief Description of the Drawings
[0027] [Figure 1] It is a figure which shows an example of a structure related to the cleaning of the head 110 of the image forming apparatus 10 according to this embodiment. [Figure 2] It is a figure which shows an example of the influence which the acceleration of the cleaning part 120 has on the cleaning performance of the cleaning part 120. [Figure 3] It is a figure which shows an example of the acceleration control of the cleaning part 120. [Figure 4] It is a figure which shows an example of the pressing force control of the cleaning part 120. [Figure 5] It is a figure which shows an example of a series of operations of the cleaning part 120. [Figure 6] It is a figure which shows an example of the variation of the cleaning part 120. [Figure 7] It is a figure which shows an example of the comparison result of the change of the relative speed of the head 110 and the cleaning part 120 in each control method 300, 310, 320. [Figure 8] It is a figure which shows an example of the comparison result of the cleaning time and the cleaning performance in each control method 300, 310, 320. [Figure 9] It is a figure which shows an example of the comparison result of the pressing force change in the control methods 400, 420. [Figure 10] It is a figure which shows an example of the comparison result of the pressing force change in the control methods 400, 430, and the comparison result of the cleaning performance in each control method 400, 420, 430.
Embodiments for Carrying Out the Invention
[0028] The embodiments of the technical concept relating to this disclosure will be described below with reference to the drawings. In the following description, the same parts are denoted by the same reference numerals. Their names and functions are also the same. Therefore, detailed descriptions of them will not be repeated. Furthermore, each embodiment, each modification, each software or program configuration, each hardware configuration, each function, and each process may be selectively combined as appropriate.
[0029] <Configuration and operation of the image forming apparatus> (Configuration of an image forming apparatus) Figure 1 shows an example of a configuration related to cleaning the head 110 of an image forming apparatus 10 according to this embodiment. The image forming apparatus 10 is, for example, an inkjet printer and comprises a control unit 100, a head 110, and a cleaning unit 120.
[0030] The control unit 100 controls the operation of the head 110 and the cleaning unit 120. The control unit 100 may also be configured to control the entire image forming apparatus 10. The control unit 100 can drive the head 110 and the cleaning unit 120 via a motor and a motor control circuit, etc.
[0031] The print head 110 applies ink to the medium and forms an image on the medium. Multiple head modules may be provided at the bottom of the print head 110 (also called the nozzle surface). In this case, each of the multiple head modules is equipped with multiple nozzles for ejecting ink. Multiple head modules may be arranged in a staggered pattern at the bottom of the print head 110. Alternatively, the print head 110 may be equipped with multiple nozzles directly. Furthermore, the print head 110 is connected to a motor (not shown) for driving the print head via drive components and the like.
[0032] The cleaning unit 120 cleans the nozzle surface of the head 110. If the head 110 is provided with multiple head modules, the cleaning unit 120 cleans the nozzle surface of each of the multiple head modules. If multiple nozzles are directly provided on the head 110, the cleaning unit 120 cleans the nozzle surfaces directly provided on the head 110.
[0033] The cleaning unit 120 includes, for example, a cleaning member 122, a support member 128, a first roller 124, and a second roller 126. The cleaning member 122 is a member for wiping away dirt from the head 110. For example, the cleaning member 122 may be a wiping cloth.
[0034] The support member 128 presses the cleaning member 122 against the head 110 when the cleaning unit 120 is in contact with the head 110. The cleaning unit 120 is configured to be able to press against or separate from the head by being driven by a motor (not shown). The state in which the cleaning unit 120 is in contact with the head 110 is when the support member 128 is pressing the cleaning member 122 against the nozzle surface of the head 110.
[0035] The first roller 124 is a roller on which the cleaning member 122 is wound, and it feeds out the cleaning member 122. The second roller 126 is a roller that winds up the cleaning member 122. The cleaning member 122 is fed out from the first roller 124, pressed against the nozzle surface of the head 110 by the support member 128, and then wound up onto the second roller 126.
[0036] When cleaning the head 110, the cleaning unit 120 moves relative to the head 110 in a direction 140 opposite to the scanning direction 130. That is, when cleaning the head 110, the cleaning unit 120 may not move, and the head 110 may move in the scanning direction 130. Alternatively, when cleaning the head 110, the cleaning unit 120 may move in direction 140, and the head 110 may not move. Furthermore, when cleaning the head 110, the cleaning unit 120 may move in direction 140, and the head 110 may move in the scanning direction 130. Hereafter, when the cleaning unit 120 moves relative to the head 110, it will be described as "the cleaning unit 120 moves relative to the head 110".
[0037] (Vibrations that may occur during head cleaning) The image forming apparatus 10 can remove dirt from the nozzle surface of the head 110 by including a cleaning unit 120. However, the head 110 may vibrate at the start and end timings of cleaning, as well as around these timings. At the start of cleaning, the friction between the head 110 and the cleaning unit 120 changes from static friction to dynamic friction. At this time, a large shock may occur to the head 110. Therefore, the head 110 is likely to vibrate at the start of cleaning. Similarly, at the end of cleaning, the friction between the head 110 and the cleaning unit 120 changes from dynamic friction to static friction. At this time, a large shock may occur to the head 110. Therefore, the head 110 is likely to vibrate at the end of cleaning. If the head 110 is cleaned while vibrating, the nozzle surface of the head 110 may not be cleaned sufficiently. In addition, the cleaning unit 120 may behave unintended due to the effects of vibration, which may cause scratches on the nozzle surface of the head 110. Therefore, it is desirable to suppress vibration of the head 110 at the start and end timings of the cleaning of the head 110.
[0038] In this specification, "cleaning start timing" includes the timing when the cleaning member 122 begins relative movement while the cleaning member 122 is in contact with the head 110. In this specification, "cleaning end timing" includes the timing when the cleaning member 122 ends relative movement while the cleaning member 122 is in contact with the head 110. Furthermore, "cleaning start timing" may include the time range from the timing when the cleaning member 122 begins relative movement while the cleaning member 122 is in contact with the head 110 until the cleaning member 122 has traveled a predetermined distance. In other words, "cleaning start timing" may include a certain period from the start of cleaning. Similarly, "cleaning end timing" may include the time range when the cleaning member 122 has traveled a predetermined distance while the cleaning member 122 is in contact with the head 110 until the cleaning member 122 ends relative movement. In other words, "cleaning end timing" may include a certain period from the middle of cleaning until the end of cleaning.
[0039] (Control of the cleaning unit to suppress head vibration) As mentioned above, vibrations of the head 110 are likely to occur at the start and end of cleaning. Or, vibrations of the head 110 are likely to occur around the start and end of cleaning. Therefore, the control unit 100 adjusts at least one of the relative speed or pressing force of the cleaning unit 120 based on predetermined operation settings of the cleaning unit 120. More specifically, the control unit 100 adjusts at least one of the relative speed or pressing force of the cleaning unit 120 within a range that can suppress vibrations generated in the head 110 due to cleaning to below a predetermined reference value. Furthermore, the control unit 100 may adjust at least one of the relative speed or pressing force of the cleaning unit 120 in steps. In addition, the control unit 100 may combine adjustments of relative speed and pressing force. Specific examples of relative speed control will be described later with reference to Figure 3. Specific examples of pressing force control will be described later with reference to Figure 4.
[0040] The control unit 100 can read a predetermined operation setting and adjust at least one of the relative speed or pressing force of the cleaning unit 120 based on that operation setting. The predetermined operation setting includes at least one of the following: information on acceleration that can suppress vibrations generated in the head 110 due to cleaning to a predetermined reference value or less, and information on the amount of change in pressing force. In this specification, "acceleration of the cleaning unit 120" refers to "the degree of change in relative speed between the head 110 and the cleaning unit 120." Also, in this specification, "pressing force of the cleaning unit 120" is the force with which the cleaning unit 120 presses the cleaning member 122 against the head 110. The operation setting can be prepared in advance by experiment based on findings such as those shown in Figure 2. The control unit 100 may include a processor, storage, and memory. In this case, the processor may read the operation setting stored in storage into memory and refer to it. The processor can adjust at least one of the relative speed or pressing force of the cleaning unit 120 by referring to the operation setting and executing a program for cleaning the head 110. As a result, the image forming apparatus 10 can suppress vibrations of the head 110 during cleaning. In particular, the image forming apparatus 10 can effectively suppress vibrations of the head 110 at the start and end timings of cleaning, as well as at timings near these times.
[0041] As described with reference to Figure 1, the image forming apparatus 10 includes a head 110 having nozzles for ejecting ink, a cleaning unit 120 for cleaning the head 110, and a control unit 100 for controlling the cleaning unit 120. The cleaning unit 120 is movable relative to the head 110 and is configured to clean the head 110 by moving relative to the head 110 while in contact with the head 110. The control unit 100 is configured to adjust at least one of the relative speed or pressing force of the cleaning unit 120 relative to the head 110 based on predetermined operation settings of the cleaning unit 120. The predetermined operation settings include at least one of information regarding acceleration and information regarding the amount of change in pressing force that can suppress vibrations generated in the head 110 due to cleaning to a predetermined reference value or less.
[0042] Furthermore, the predetermined operation settings may include (i) information relating to the cleaning performance of the cleaning unit 120 for each relative speed of the cleaning unit 120 with respect to the head 110, and a value indicating the magnitude of vibration generated in the head 110. Furthermore, the predetermined operation settings may include (ii) information relating to the cleaning performance of the cleaning unit 120 for each pressing force applied to the head 110, and a value indicating the magnitude of vibration generated in the head 110. Alternatively, the predetermined operation settings may include both (i) and (ii). As an example, the acceleration of the cleaning unit 120 may be determined based on the information in (i) such that the vibration is below a predetermined reference value and the cleaning performance is above a predetermined reference value. Similarly, the amount of change in the pressing force of the cleaning unit 120 may be determined based on the information in (ii) such that the vibration is below a predetermined reference value and the cleaning performance is above a predetermined reference value.
[0043] The print head 110 may also include multiple head modules for ejecting ink. The control unit 100 may move the cleaning unit 120 to clean each of the multiple head modules.
[0044] Furthermore, the control unit 100 may be configured to control the cleaning unit 120 to perform a cleaning process for each of the multiple head modules. Also, adjusting the relative speed of the cleaning unit 120 with respect to the head 110 may include adjusting the relative speed of the cleaning unit 120 with respect to each of the multiple head modules.
[0045] (Cleaning unit operation settings) Figure 2 shows an example of the effect of the acceleration of the cleaning unit 120 on the cleaning performance of the cleaning unit 120.
[0046] Graph 200 shows the correlation between the acceleration of the cleaning unit 120 during cleaning and the magnitude of the vibration of the head 110 during cleaning. The horizontal axis of Graph 200 represents the acceleration of the cleaning unit 120. The vertical axis of Graph 200 represents the magnitude of the vibration of the head 110 during cleaning. Referring to Graph 200, it can be seen that the greater the acceleration of the cleaning unit 120, the greater the vibration of the head 110.
[0047] Graph 210 shows the correlation between the magnitude of vibration of the head 110 during cleaning and the cleaning performance of the cleaning unit 120. The horizontal axis of Graph 210 represents the magnitude of vibration of the head 110 during cleaning. The vertical axis of Graph 210 represents the cleaning performance of the cleaning unit 120. Referring to Graph 210, it can be seen that the greater the vibration of the head 110 during cleaning, the lower the cleaning performance of the cleaning unit 120.
[0048] As can be seen from graphs 200 and 210, in order for the cleaning unit 120 to maintain sufficient cleaning performance, the vibration of the head 110 must be kept below a certain level. Furthermore, the vibration of the head 110 is proportional to the acceleration of the cleaning unit 120. This information can be obtained through experiments, etc. Furthermore, from this information, the operational settings related to the acceleration of the cleaning unit 120 can be determined, for example, by the following procedure: Let "X" be the cleaning performance that the cleaning unit 120 must satisfy. Assume that in order for the cleaning unit 120 to exhibit cleaning performance "X", the magnitude of the vibration of the head 110 must be "Y" or less. Also, assume that in order for the magnitude of the vibration of the head 110 to be "Y" or less, the acceleration of the cleaning unit 120 must be "Z" or less. In this case, the predetermined reference value for the vibration generated in the head 110 due to cleaning is "Y". The range of acceleration that can suppress the vibration generated in the head 110 to "Y" or less is "Z" or less. Therefore, the operation setting for the acceleration of the cleaning unit 120 may include an acceleration of "Z" or less for the cleaning unit 120.
[0049] Furthermore, it is assumed that information showing the correlation between the pressing force of the cleaning unit 120 during cleaning and the magnitude of vibration of the head 110 during cleaning has been obtained through experiments, etc. In this case, the operation settings related to the pressing force of the cleaning unit 120 can be determined using the same procedure as the operation settings related to the acceleration of the cleaning unit 120.
[0050] Furthermore, let's assume that information showing the correlation between the acceleration and pressing force of the cleaning unit 120 during cleaning and the magnitude of vibration of the head 110 during cleaning has been obtained through experiments or other means. In this case, the operation settings for the combination of acceleration and pressing force of the cleaning unit 120 can be determined using the same procedure as the operation settings for the acceleration of the cleaning unit 120.
[0051] <Control of the cleaning unit> Next, referring to Figures 3 and 5, a process for suppressing vibration of the head 110 by controlling the acceleration of the cleaning unit 120 will be described. Similarly, referring to Figures 4 and 5, a process for suppressing vibration of the head 110 by controlling the pressing force of the cleaning unit 120 will be described. These processes may be used in combination.
[0052] (Acceleration control of the cleaning unit) Figure 3 shows an example of acceleration control of the cleaning unit 120. Three control methods 300, 310, and 320 are shown in Figure 3. Graphs 305, 315, and 325 show the change in relative velocity from the start timing to the end timing of cleaning in each control method. The slope of each graph represents the acceleration of the cleaning unit 120. A slope of "0" in each graph indicates that the acceleration of the cleaning unit 120 is 0 or approximately zero.
[0053] (Acceleration control of the cleaning unit that does not take head vibration into account) Control method 300 is a method of controlling the acceleration of the cleaning unit 120 without considering the vibration of the head 110. Graph 305 shows the change in relative velocity from the start timing to the end timing of cleaning in the cleaning unit 120 controlled by control method 300.
[0054] In control method 300, the cleaning start timing is period 301. Period 301 corresponds to the period during which the first section 510 in Figure 5 is being cleaned. The first section 510 is the section that includes the cleaning start position 502 to the first point 504. In control method 300, the cleaning end timing is period 302. Period 302 corresponds to the period during which the second section 520 in Figure 5 is being cleaned. The second section 520 is the section that includes the cleaning end position 508 to the second point 506. Another timing in control method 300 is period 303. Period 303 corresponds to the period during which the third section 530 in Figure 5 is being cleaned. The third section 530 is the section that includes the cleaning start position 504 to the second point 506.
[0055] The positions of the first point 504 and the second point 506 may be predetermined. In this case, the operation setting may include information on the positions of the first point 504 and the second point 506. The first section 510, the second section 520, and the third section 530 may be predetermined. In this case, the operation setting may include information on the first section 510, the second section 520, and the third section 530. The control unit 100 can determine the sections in which the cleaning unit 120 will be moved at acceleration, constant speed, and deceleration by referring to the information on each point or section included in the operation setting.
[0056] Referring to Graph 305, it can be seen that the change in the relative speed of the cleaning unit 120 follows a trapezoidal curve. This type of control is sometimes called trapezoidal drive. In trapezoidal drive, the cleaning unit 120 initially accelerates gradually, then moves at a constant speed, and finally decelerates gradually. However, if the vibration of the head 110 is not taken into consideration, the acceleration or deceleration of the cleaning unit 120 at the start and end of cleaning may be too abrupt, causing the head 110 to vibrate. Therefore, it is desirable that the acceleration value of the cleaning unit 120 be set to a value that can suppress the vibration of the head 110 to an acceptable range.
[0057] (Acceleration control of the cleaning unit that takes head vibration into consideration) The control method 310 is a method of controlling the acceleration of the cleaning unit 120 so that vibrations can be suppressed to a predetermined reference value or less. Graph 315 shows the change in relative velocity from the start timing to the end timing of cleaning in the cleaning unit 120 controlled by the control method 310.
[0058] In control method 310, the cleaning start timing is period 311. Period 311 corresponds to the period during which the first section 510 in Figure 5 is being cleaned. In control method 310, the cleaning end timing is period 312. Period 312 corresponds to the period during which the second section 520 in Figure 5 is being cleaned. In control method 310, all other timings are in period 313. Period 313 corresponds to the period during which the third section 530 in Figure 5 is being cleaned.
[0059] Referring to Graph 315, it can be seen that the change in the relative velocity of the cleaning unit 120 follows a trapezoidal curve, similar to Graph 305. However, the acceleration B of the cleaning unit 120 during period 311 in control method 310 is gentler than the acceleration A of the cleaning unit 120 during period 301 in control method 300. The value of acceleration B is within the range of acceleration that can suppress vibrations generated in the head 110 due to cleaning to a predetermined reference value or less. By using control method 310, the image forming apparatus 10 can clean the head 110 while suppressing vibrations of the head 110, although the cleaning time is longer than when using control method 300.
[0060] (Acceleration control of the cleaning unit, taking into account head vibration and cleaning time) The control method 320 is a method of controlling the cleaning unit 120 by gradually changing its acceleration so that the vibration of the head 110 can be suppressed to a predetermined reference value or less. Graph 325 shows the change in relative speed from the start timing to the end timing of cleaning in the cleaning unit 120 controlled by the control method 320.
[0061] In control method 320, the cleaning start timing is period 321. Period 321 corresponds to the period during which the first section 510 in Figure 5 is being cleaned. In control method 320, the cleaning end timing is period 322. Period 322 corresponds to the period during which the second section 520 of the head 110 in Figure 5 is being cleaned. In control method 320, all other timings are in period 323. Period 323 corresponds to the period during which the third section 530 in Figure 5 is being cleaned.
[0062] Referring to Graph 325, it can be seen that, unlike Graphs 305 and 315, the relative velocity of the cleaning unit 120 changes in steps at the start and end of cleaning. For example, at the start of cleaning, the cleaning unit 120 accelerates in steps in the order of accelerations C1, C2, and C3. That is, the acceleration of the cleaning unit 120 changes in steps. Similarly, at the end of leaning, the cleaning unit 120 decelerates in steps. The acceleration of the cleaning unit 120 may change nonlinearly in a curved manner at the start and end of cleaning. Stepwise acceleration and deceleration as described herein also include nonlinear changes in the acceleration of the cleaning unit 120.
[0063] Once cleaning begins, dynamic friction is constantly generated between the head 110 and the cleaning unit 120, making the head 110 less prone to vibration. Therefore, even if the acceleration of the cleaning unit 120 increases in stages, the vibration of the head 110 can be suppressed to below a predetermined standard value. Gradually increasing the acceleration of the cleaning unit 120 has the effect of suppressing the vibration of the head 110 while shortening the cleaning time.
[0064] The acceleration values of the cleaning unit 120 at the start and end timings of cleaning, the number of acceleration changes, and the acceleration values at each stage of change can be determined experimentally. These experimentally obtained values are included in the operation settings. The control unit 100 can perform either of the control methods 310 or 320 by referring to the operation settings. As a result, the image forming apparatus 10 can gradually change the acceleration of the cleaning unit 120 while suppressing the vibration of the head 110 to below a predetermined reference value.
[0065] (Summary of acceleration control in the cleaning unit) As described with reference to Figures 3 and 5, the cleaning unit 120 is configured to move from the cleaning start position 502 to the first point 504 in a first section 510, which includes the cleaning start position 502 of the head 110 to the first point 504. Adjusting the relative speed of the cleaning unit 120 with respect to the head 110 includes accelerating the relative speed in the first section 510. The process of accelerating the relative speed in the first section 510 corresponds to control methods 310 and 320.
[0066] Furthermore, in the first section 510, accelerating the relative speed includes gradually increasing the relative speed. The process of gradually increasing the relative speed corresponds to control method 320.
[0067] Furthermore, the cleaning unit 120 is configured to move from the second point 506 toward the cleaning end position 508 in a second section 520 that includes the section from the cleaning end position 508 of the head 110 toward the second point 506. Adjusting the relative speed of the cleaning unit 120 with respect to the head 110 includes reducing the relative speed in the second section 520. The process of reducing the relative speed in the second section 520 corresponds to control methods 310 and 320.
[0068] Furthermore, in the second section 520, reducing the relative speed includes gradually decreasing the relative speed. The process of gradually decreasing the relative speed corresponds to control method 320.
[0069] Furthermore, the cleaning unit 120 is configured to move from the first point 504 to the second point 506 in a third section 530 which includes the section from the first point 504 to the second point 506. Adjusting the relative speed of the cleaning unit 120 with respect to the head 110 includes making the acceleration of the relative speed approximately zero in the third section 530. The process of making the acceleration of the relative speed approximately zero in the third section 530 corresponds to control methods 310 and 320.
[0070] The image forming apparatus 10 can clean the head 110 by suppressing vibrations generated in the head 110 to below a predetermined reference value by using either control method 310 or 320. Although control methods 310 and 320 have been explained using trapezoidal drive as an example with reference to Figure 3, control methods 310 and 320 are also applicable to drive methods other than trapezoidal drive. For example, control methods 310 and 320 are also applicable to triangular drive and curve drive. Regardless of which drive method control method 310 or 320 is applied to, the image forming apparatus 10 adjusts the acceleration of the cleaning unit 120 so that the vibrations of the head 110 can be suppressed to below a predetermined reference value.
[0071] (Pressure control of the cleaning unit) Figure 4 shows an example of pressing force control for the cleaning unit 120. Figure 4 shows four control methods 400, 410, 420, and 430. Graphs 405, 415, 425, and 435 show the change in pressing force of the cleaning unit 120 from the start timing to the end timing of cleaning in each control method. The slope of each graph indicates the change in pressing force of the cleaning unit 120. A slope of "0" in each graph indicates that the change in pressing force of the cleaning unit 120 is 0 or approximately zero.
[0072] (Pressure control of the cleaning unit without considering head vibration) Control method 400 is a method of controlling the pressing force of the cleaning unit 120 without considering the vibration of the head 110. Graph 405 shows the change in pressing force in the cleaning unit 120 controlled by control method 400 from the start timing to the end timing of cleaning. Referring to graph 405, it can be seen that the pressing force of the cleaning unit 120 is constant throughout the entire period 401. Period 401 in control method 400 corresponds to the period during which the first section 510, second section 520, and third section 530 in Figure 5 are being cleaned.
[0073] In control method 400, the pressing force of the cleaning unit 120 is determined without considering the vibration of the head 110. Therefore, when the cleaning unit 120 is controlled based on control method 400, the pressing force of the cleaning unit 120 at the start and end of cleaning may be too high, potentially causing the head 110 to vibrate. For this reason, it is desirable that the value of the pressing force of the cleaning unit 120 be set to a value that can suppress the vibration of the head 110 to an acceptable range.
[0074] (Pressure control of the cleaning unit that takes head vibration into consideration) Control method 410 is a method of controlling the pressing force of the cleaning unit 120 while taking into account the vibration of the head 110. Graph 415 shows the change in pressing force in the cleaning unit 120 controlled by control method 410 from the start timing to the end timing of cleaning. Referring to graph 415, it can be seen that the pressing force of the cleaning unit 120 is constant throughout the entire period 411. The period 411 in control method 410 corresponds to the period during which the first section 510, the second section 520, and the third section 530 in Figure 5 are being cleaned.
[0075] In control method 410, the pressing force of the cleaning unit 120 is determined considering the vibration of the head 110. More specifically, the pressing force of the cleaning unit 120 is set to a value such that the head 110 does not vibrate at the start and end timings of cleaning. Therefore, if the cleaning unit 120 is controlled based on control method 410, vibration of the head 110 may not occur, but the pressing force of the cleaning unit 120 may be too low, and the head 110 may not be sufficiently cleaned. For this reason, preferably, the value of the pressing force of the cleaning unit 120 should be set considering not only the vibration of the head 110 but also the cleaning performance of the cleaning unit 120.
[0076] (Pressure control of the cleaning unit, taking into account head vibration and cleaning performance of the cleaning unit) Control method 420 is a method of controlling the pressing force of the cleaning unit 120, taking into consideration the vibration of the head 110 and the cleaning performance of the cleaning unit 120. Graph 425 shows the change in pressing force from the start timing to the end timing of cleaning in the cleaning unit 120 controlled by control method 420.
[0077] Referring to Graph 425, it can be seen that the change in the pressing force of the cleaning unit 120 follows a trapezoidal curve. More specifically, in control method 420, the pressing force of the cleaning unit 120 increases gradually at the start of cleaning. Also, the pressing force of the cleaning unit 120 decreases gradually at the end of cleaning. Furthermore, at timings other than the start and end of cleaning, the pressing force of the cleaning unit 120 is kept constant, or the change in the pressing force of the cleaning unit 120 is kept approximately zero.
[0078] In control method 420, the cleaning start timing is period 421. Period 421 corresponds to the period during which the first section 510 in Figure 5 is being cleaned. In control method 420, the cleaning end timing is period 422. Period 422 corresponds to the period during which the second section 520 in Figure 5 is being cleaned. In control method 420, any other timing is period 423. Period 423 corresponds to the period during which the third section 530 in Figure 5 is being cleaned.
[0079] Vibration of the head 110 is likely to occur at the start and end of cleaning. Therefore, when the control method 420 is adopted, the control unit 100 gradually increases the pressing force of the cleaning unit 120 at the start of cleaning, within a range that can suppress the vibration of the head 110 to below a predetermined reference value. Also, at the end of cleaning, the control unit 100 gradually decreases the pressing force of the cleaning unit 120 within a range that can suppress the vibration of the head 110 to below a predetermined reference value. During other periods, the control unit 100 maintains the pressing force of the cleaning unit 120 at a value sufficient to adequately clean the head 110. In this way, the image forming apparatus 10 can adequately clean the head 110 while suppressing vibration of the head 110.
[0080] (Variations in the pressing force control of the cleaning unit, taking into account head vibration and cleaning performance of the cleaning unit) Control method 430 is a method of controlling the pressing force of the cleaning unit 120, taking into consideration the vibration of the head 110 and the cleaning performance of the cleaning unit 120. Control method 430 differs from control method 420 in that the cleaning unit 120 separates from the head 110 at the cleaning completion timing. Graph 435 shows the change in pressing force from the start timing to the end timing of cleaning in the cleaning unit 120 controlled by control method 430.
[0081] In control method 430, the cleaning start timing is period 431. Period 431 corresponds to the period during which the first section 510 in Figure 5 is being cleaned. In control method 430, the cleaning end timing is period 432. Period 432 corresponds to the period during which the second section 520 in Figure 5 is being cleaned. In control method 430, all other timings are in period 433. Period 433 corresponds to the period during which the third section 530 in Figure 5 is being cleaned.
[0082] Comparing the period 422 in graph 425 with the period 432 in graph 435, it can be seen that at the end of cleaning, only the pressing force in graph 435 is zero. This is because at the end of cleaning, the cleaning unit 120 has moved away from the head 110. Thus, even if the cleaning unit 120 moves away from the head 110 at the end of cleaning, the image forming apparatus 10 can sufficiently clean the head 110 while suppressing vibrations of the head 110.
[0083] The number of changes in pressing force at the start and end timings of cleaning, and the value of the change in pressing force at each change stage, can be determined by experiment. These values obtained by experiment are included in the operation settings. The control unit 100 can perform either of the control methods 420 or 430 by referring to the operation settings. As a result, the image forming apparatus 10 can suppress the vibration of the head 110 to a predetermined reference value or less, while maintaining the pressing force of the cleaning unit 120 at a value sufficient to adequately clean the head 110.
[0084] (Summary of pressure control for the cleaning unit) As explained with reference to Figures 4 and 5, adjusting the pressing force of the cleaning unit 120 against the head 110 includes gradually increasing the pressing force of the cleaning unit 120 against the head 110 in the first section 510.
[0085] Furthermore, adjusting the pressing force of the cleaning unit 120 against the head 110 includes gradually reducing the pressing force of the cleaning unit 120 against the head 110 in the second section 520.
[0086] Furthermore, the control unit 100 may control the cleaning unit 120 so that it moves away from the head 110 once it has passed the area to be cleaned on the head 110. The area to be cleaned is the combined area of the first section 510, the second section 520, and the third section 530. Control methods 420 and 430 adjust the pressing force of the cleaning unit 120 against the head 110 in a trapezoidal drive manner, but this is only one example. Control methods 420 and 430 may also adjust the pressing force of the cleaning unit 120 against the head 110 in a triangular drive or curved drive manner. In any case, the image forming apparatus 10 adjusts the pressing force of the cleaning unit 120 so that the vibration of the head 110 can be suppressed to a predetermined reference value or less.
[0087] (Operation of the cleaning unit) Figure 5 shows an example of a series of operations of the cleaning unit 120. The control unit 100 transmits control signals to the cleaning unit 120, causing the cleaning unit 120 to perform the series of operations shown in Figure 5. In the example in Figure 5, the cleaning unit 120 is configured to be movable so as to press against and move away from the head 110. Furthermore, while in contact with the head 110, the cleaning unit 120 is configured to be movable in a direction 140 opposite to the scanning direction 130 of the head 110.
[0088] As another example, the head 110 may be configured to move in and out of contact with the cleaning unit 120. Alternatively, the head 110 may be configured to move in the scanning direction 130 while in contact with the cleaning unit 120. Yet another example is that both the head 110 and the cleaning unit 120 may be configured to move in and out of contact with each other. Alternatively, the head 110 and the cleaning unit 120 may be configured to move in opposite directions while in contact with each other. For example, the head 110 may move in the scanning direction 130 and the cleaning unit 120 may move in the direction 140.
[0089] First, the cleaning unit 120 presses against the cleaning start position 502 of the head 110. Next, while still pressed against the head 110, the cleaning unit 120 moves toward the cleaning end position 508.
[0090] The cleaning unit 120 adjusts at least one of the relative speed or pressing force in the first section 510, which includes the cleaning start position 502 and the first point 504. More specifically, the cleaning unit 120 may accelerate by one or more steps in the first section 510. The cleaning unit 120 may also increase the pressing force by one or more steps in the first section 510. The cleaning unit 120 may also accelerate and increase the pressing force by one or more steps in the first section 510. The acceleration of the cleaning unit 120, the amount of increase in the pressing force of the cleaning unit 120, the number of changes in the acceleration of the cleaning unit 120, and the number of increases in the pressing force of the cleaning unit 120 are set to values within a range that can suppress the vibration of the head 110 to a predetermined reference value or less, based on the operation settings.
[0091] The cleaning unit 120 can maintain a constant relative speed in the third section 530, which includes the first point 504 and the second point 506. Alternatively, the cleaning unit 120 can maintain a change in relative speed of approximately zero in the third section 530. Similarly, the cleaning unit 120 can maintain a constant pressing force in the third section 530. Alternatively, the cleaning unit 120 can maintain a change in pressing force of the cleaning unit 120 of approximately zero in the third section 530.
[0092] The cleaning unit 120 adjusts at least one of the relative speed or pressing force in the second section 520, which includes the second point 506 and the cleaning end position 508. More specifically, the cleaning unit 120 may decelerate by one or more steps in the second section 520. The cleaning unit 120 may also reduce the pressing force by one or more steps in the second section 520. The cleaning unit 120 may decelerate by one or more steps and reduce the pressing force in the second section 520. The acceleration (i.e., deceleration) of the cleaning unit 120, the amount of reduction in the pressing force of the cleaning unit 120, the number of changes in the acceleration of the cleaning unit 120, and the number of reductions in the pressing force of the cleaning unit 120 are set to values within a range that can suppress the vibration of the head 110 to a predetermined reference value or less, based on the operation settings.
[0093] The cleaning unit 120 may move away from the head 110 at the same time it reaches the cleaning completion position 508. The cleaning unit 120 may stop briefly after reaching the cleaning completion position 508 and then move away from the head 110. The cleaning unit 120 may move away from the head 110 after passing the cleaning completion position 508.
[0094] <Variations in the cleaning department> Figure 6 shows an example of a variation of the cleaning unit 120. The cleaning unit 120 may have any configuration for cleaning the nozzle surface of the head 110.
[0095] As an example, the cleaning unit 120 includes a cleaning member 122 for wiping dirt off the head 110 and a support member 128 for pressing the cleaning member 122 against the head 110. Furthermore, the cleaning unit 120 includes a first roller 124 for feeding out the cleaning member 122 and a second roller 126 for winding up the cleaning member 122. The cleaning unit 120 is configured to transport the cleaning member 122 in the opposite direction to the direction of movement of the head 110 as viewed from the cleaning unit 120, using the first roller 124 and the second roller 126. The direction of movement of the head 110 is the scanning direction 130.
[0096] As another example, the cleaning unit 120 may include a roller-shaped elastic body 620 for wiping dirt off the head 110. In this case, the roller-shaped elastic body 620 rotates and moves relative to the cleaning start position 502 from the cleaning end position 508. Dirt on the nozzle surface of the head 110 is cleaned by the roller-shaped elastic body 620.
[0097] As another example, the cleaning unit 120 may include a pad-shaped elastic body 630 for wiping dirt off the head 110. In this case, the pad-shaped elastic body 630 moves relative to the head from the cleaning start position 502 to the cleaning end position 508. Dirt on the nozzle surface of the head 110 is cleaned by the pad-shaped elastic body 630. As yet another example, the cleaning unit 120 may include a wiper or the like for wiping dirt off the nozzle surface of the head 110. Regardless of the shape of the cleaning unit 120, the control unit 100 can adjust at least one of the relative speed or pressing force of the cleaning unit 120 relative to the head 110 based on predetermined operation settings.
[0098] <Performance comparison of each control method> Figure 7 shows an example of the comparison results of the relative speed changes of the head 110 and the cleaning unit 120 in each control method 300, 310, and 320. Graph 700 shows the comparison results of the relative speed changes for each control method from the start to the end of cleaning of the head 110. Graph 720 is an excerpt from Graph 700 showing the comparison results of the relative speed changes for each control method from the start of cleaning up to 0.5 seconds later.
[0099] When using control method 310 or control method 320, the control unit 100 refers to an operation setting to suppress vibrations generated in the head 110 to a predetermined reference value or less. Therefore, the relative speed of the cleaning unit 120 in control method 310 or control method 320 changes more gradually compared to control method 300. Referring to graph 720, it can be seen that the amount of change in relative speed in control method 310 is smaller than the amount of change in relative speed in control method 300. Also, the change in relative speed in control method 320 is stepwise. Therefore, especially in the initial stages of cleaning, it can be seen that the amount of change in relative speed in control method 320 is smaller than the amount of change in relative speed in control method 300. From these points, it can be seen that control methods 310 and 320 are advantageous in suppressing vibrations of the head 110 compared to control method 300.
[0100] Figure 8 shows an example of a comparison of cleaning time and cleaning performance for each control method 300, 310, and 320. Graph 800 shows the comparison of cleaning times for each control method. Control method 310 has a longer cleaning time than the other control methods because the change in the relative speed of the cleaning unit 120 is small. Control method 320 suppresses vibration of the head 110 while keeping the cleaning time equivalent to that of control method 300 by gradually changing the relative speed of the cleaning unit 120.
[0101] Table 820 shows the results of a comparison of the cleaning performance of the cleaning unit 120 under each control method. Control method 300 does not take into account the vibration of the head 110. Therefore, if the image forming apparatus 10 adopts control method 300, vibration will occur in the head 110, and this vibration may reduce the cleaning performance of the cleaning unit 120. On the other hand, both control methods 310 and 320 suppress the vibration of the head 110 based on the operation settings. Therefore, if the image forming apparatus 10 adopts control method 310 or control method 320, the vibration of the head 110 is small, and the cleaning performance of the cleaning unit 120 is less likely to decrease. As a result, the cleaning performance of the cleaning unit 120 under control methods 310 and 320 is higher than that of the cleaning unit 120 under control method 300.
[0102] In other words, the image forming apparatus 10 can suppress vibrations of the head 110 and maintain the cleaning performance of the cleaning unit 120 by having a configuration that realizes the control method 310 or the control method 320. The image forming apparatus 10 has a configuration that realizes the control method 310 or the control method 320, and includes a head 110 having nozzles for ejecting ink, a cleaning unit 120 for cleaning the head 110, and a control unit 100 for controlling the cleaning unit 120. The cleaning unit 120 is movable relative to the head 110 and is configured to clean the head 110 by moving relative to the head 110 while in contact with the head 110. The control unit 100 is configured to adjust the relative speed of the cleaning unit 120 with respect to the head 110 based on predetermined operation settings of the cleaning unit 120. The predetermined operation settings include information on acceleration that can suppress vibrations generated in the head 110 due to cleaning to a predetermined reference value or less. The control unit 100 may be further configured to gradually accelerate the relative speed from the cleaning start timing of the head 110 to the first timing, to reduce the acceleration of the relative speed to approximately zero from the first timing to the second timing, and to gradually decelerate the relative speed from the second timing to the cleaning end timing of the head 110. Here, the period from the cleaning start timing to the first timing corresponds to periods 311 and 321. Here, the period from the first timing to the second timing corresponds to periods 313 and 323. Here, the period from the second timing to the cleaning end timing of the head 110 corresponds to periods 312 and 322.
[0103] Figure 9 shows an example of a comparison of the pressing force changes in control methods 400 and 420. Graph 900 shows a comparison of the pressing force changes for control methods 400 and 420 from the start to the end of cleaning the head 110. Graph 920 is an excerpt from Graph 900 showing the comparison of the pressing force changes for control methods 400 and 420 from the start of cleaning up to 0.2 seconds later. Referring to Graph 920, the pressing force is constant in control method 400, whereas in control method 420, the pressing force increases gradually at the start of cleaning. Control method 420 can suppress vibration of the head 110 compared to control method 400 by gradually changing the pressing force of the cleaning unit 120 at the start and end of cleaning.
[0104] Figure 10 shows an example of the comparison results of the pressing force change in control methods 400 and 430, and the comparison results of the cleaning performance in each control method 400, 420, and 430. Graph 1000 shows the comparison results of the pressing force change for each control method 400 and 430 from the start to the end of cleaning the head 110. Referring to Graph 1000, control method 430, like control method 420, changes the pressing force of the cleaning unit 120 in stages at the start and end timings of cleaning. In control method 430, cleaning is completed and the unit moves away from the head 110 simultaneously. Therefore, the pressing force in control method 430 becomes 0 at the cleaning completion timing. Control method 430 can also suppress vibration of the head 110 compared to control method 400 by changing the pressing force of the cleaning unit 120 in stages at the start and end timings of cleaning.
[0105] Table 1020 shows the results of a comparison of the cleaning performance of the cleaning unit 120 under each control method. Control method 400 does not take into account the vibration of the head 110. Therefore, if the image forming apparatus 10 adopts control method 400, vibration will occur in the head 110, and this vibration may reduce the cleaning performance of the cleaning unit 120. On the other hand, both control methods 420 and 430 suppress the vibration of the head 110 based on the operation settings. Therefore, if the image forming apparatus 10 adopts control method 420 or control method 430, the vibration of the head 110 is small, and the cleaning performance of the cleaning unit 120 is less likely to decrease. As a result, the cleaning performance of the cleaning unit 120 under control methods 420 and 430 is higher than that of the cleaning unit 120 under control method 400.
[0106] In other words, the image forming apparatus 10 can suppress vibration of the head 110 and maintain the cleaning performance of the cleaning unit 120 by having a configuration that realizes the control method 420 or control method 430. The image forming apparatus 10, as a configuration that realizes the control method 420 or control method 430, includes a head 110 having nozzles for ejecting ink, a cleaning unit 120 for cleaning the head 110, and a control unit 100 for controlling the cleaning unit 120. The cleaning unit 120 is movable relative to the head 110 and is configured to clean the head 110 by moving relative to the head 110 while in contact with the head 110. The control unit 100 is configured to adjust the pressing force of the cleaning unit 120 against the head 110 based on predetermined operation settings of the cleaning unit 120. The predetermined operation settings include information on the amount of change in pressing force that can suppress vibrations generated in the head 110 due to cleaning to a predetermined reference value or less. The control unit 100 may be configured to gradually increase the pressing force from the cleaning start timing of the head 110 to the first timing, to make the change in pressing force approximately zero from the first timing to the second timing, and to gradually decrease the pressing force from the second timing to the cleaning end timing of the head 110. Here, the cleaning start timing to the first timing corresponds to periods 411 and 421. Here, the first timing to the second timing corresponds to periods 413 and 423. Here, the cleaning end timing of the head 110 corresponds to periods 412 and 422.
[0107] <Summary> As described above, the image forming apparatus 10 according to this embodiment adjusts at least one of the relative speed or pressing force of the cleaning unit 120 with respect to the head 110 based on predetermined operation settings. By adjusting at least one of the relative speed or pressing force of the cleaning unit 120, the image forming apparatus 10 can suppress vibration of the head 110 during cleaning. In particular, the image forming apparatus 10 can effectively suppress vibration of the head 110 at the start and end timings of cleaning, as well as at timings near these. As a result, the cleaning performance of the cleaning unit 120 is improved compared to conventional methods, and the risk of scratching the nozzle surface of the head 110 is also reduced.
[0108] The embodiments disclosed herein should be considered in all respects as illustrative and not restrictive. The scope of this disclosure is indicated by the claims rather than the foregoing description, and all modifications are intended to be equivalent to the claims. Furthermore, the disclosures described in the embodiments and each variation are intended to be implemented, as far as possible, individually or in combination. [Explanation of Symbols]
[0109] 10 Image forming apparatus, 100 Control unit, 110 Head, 120 Cleaning unit, 122 Cleaning member, 124 First roller, 126 Second roller, 128 Support member, 130 Scanning direction, 140 Direction, 200, 210, 305, 315, 325, 405, 415, 425, 435, 700, 720, 800, 900, 920, 1000 Graph, 300, 310, 320, 400, 410, 420, 430 Control method, 301, 302, 303, 311, 312, 313, 321, 322, 323, 401, 411, 421, 422, 423, 431, 432, 433 Period, 502 Cleaning start position, 504 First point, 506 Second point, 508 Cleaning end position, 510 First section, 520 Second section, 530 Third section, 620 Roller-shaped elastic body, 630 Pad-shaped elastic body, 820, 1020 Table.
Claims
1. A head having a nozzle for ejecting ink, A cleaning unit for cleaning the head, The system includes a control unit that controls the cleaning unit, The cleaning unit is It is movable relative to the head, The device is configured to clean the head by moving relative to the head while in contact with the head. The control unit is configured to adjust at least one of the relative speed or pressing force of the cleaning unit with respect to the head, based on predetermined operating settings of the cleaning unit. The aforementioned predetermined operation setting includes at least one of the following: information regarding acceleration and information regarding the amount of change in pressing force, which can suppress vibrations generated in the head due to the cleaning to a predetermined reference value or less.
2. The image forming apparatus according to claim 1, wherein the predetermined operation setting includes at least one of (i) information relating the cleaning performance of the cleaning unit for each relative speed of the cleaning unit to the head and a value indicating the magnitude of vibrations generated in the head, and (ii) information relating the cleaning performance of the cleaning unit for each pressing force of the cleaning unit to the head and a value indicating the magnitude of vibrations generated in the head.
3. The cleaning unit is configured to move from the cleaning start position toward the first point in a first section including from the cleaning start position of the head toward the first point. The image forming apparatus according to claim 1 or 2, wherein adjusting the relative speed of the cleaning unit with respect to the head includes accelerating the relative speed in the first section.
4. The image forming apparatus according to claim 3, wherein accelerating the relative speed in the first section includes gradually increasing the relative speed.
5. The cleaning unit is configured to move from the second point toward the cleaning end position in a second section including from the cleaning end position of the head toward the second point. The image forming apparatus according to claim 3, wherein adjusting the relative speed of the cleaning unit with respect to the head includes reducing the relative speed in the second section.
6. The image forming apparatus according to claim 5, wherein reducing the relative speed in the second section includes gradually decreasing the relative speed.
7. The cleaning unit is configured to move from the first point to the second point in a third section including the section from the first point to the second point. The image forming apparatus according to claim 5, wherein adjusting the relative speed of the cleaning unit with respect to the head includes making the acceleration of the relative speed substantially zero in the third section.
8. The image forming apparatus according to claim 3, wherein adjusting the pressing force of the cleaning unit against the head includes gradually increasing the pressing force of the cleaning unit against the head in the first section.
9. The image forming apparatus according to claim 5, wherein adjusting the pressing force of the cleaning unit against the head includes gradually decreasing the pressing force of the cleaning unit against the head in the second section.
10. The image forming apparatus according to claim 1 or 2, wherein the control unit controls the cleaning unit to move away from the head when the cleaning unit has passed the area to be cleaned on the head.
11. The cleaning unit is A cleaning member for wiping away dirt from the head, The image forming apparatus according to claim 1 or 2, further comprising a support member for pressing the cleaning member against the head.
12. The cleaning unit is A first roller that feeds out the cleaning member, The system further comprises a second roller for winding up the cleaning member, The image forming apparatus according to claim 11, wherein the cleaning member is transported in the opposite direction to the direction of movement of the head as viewed from the cleaning unit, using the first roller and the second roller.
13. The image forming apparatus according to claim 1 or 2, wherein the cleaning unit comprises a roller-shaped elastic body for wiping off dirt from the head.
14. The image forming apparatus according to claim 1 or 2, wherein the cleaning unit comprises a pad-shaped elastic body for wiping off dirt from the head.
15. The head comprises multiple head modules for ejecting ink, The image forming apparatus according to claim 1 or 2, wherein the control unit moves the cleaning unit to clean each of the plurality of head modules.
16. The control unit is configured to control the cleaning unit to perform a cleaning process for each of the plurality of head modules. The image forming apparatus according to claim 15, wherein adjusting the relative speed of the cleaning unit with respect to the head includes adjusting the relative speed of the cleaning unit with respect to each of the plurality of head modules.
17. A head having a nozzle for ejecting ink, A cleaning unit for cleaning the head, The system includes a control unit that controls the cleaning unit, The cleaning unit is It is movable relative to the head, The device is configured to clean the head by moving relative to the head while in contact with the head. The control unit is configured to adjust the relative speed of the cleaning unit with respect to the head based on predetermined operating settings of the cleaning unit. The aforementioned predetermined operation settings include information regarding acceleration that can suppress vibrations generated in the head due to the cleaning to a predetermined reference value or less. The control unit further, From the cleaning start timing of the head to the first timing, the relative speed is gradually accelerated. From the first timing to the second timing, the acceleration of the relative velocity is made approximately zero. An image forming apparatus configured to gradually reduce the relative speed from the second timing until the timing at which the cleaning of the head is completed.
18. A head having a nozzle for ejecting ink, A cleaning unit for cleaning the head, The system includes a control unit that controls the cleaning unit, The cleaning unit is It is movable relative to the head, The device is configured to clean the head by moving relative to the head while in contact with the head. The control unit is configured to adjust the pressing force of the cleaning unit against the head based on a predetermined operation setting of the cleaning unit. The predetermined operation settings include information regarding the amount of change in pressing force that can suppress the vibrations generated in the head due to the cleaning to a predetermined reference value or less. The control unit further, From the timing of the start of cleaning of the head to the first timing, the pressing force is gradually increased. From the first timing to the second timing, the change in the pressing force is made approximately zero. An image forming apparatus configured to gradually reduce the pressing force from the second timing until the timing at which the cleaning of the head is completed.