Liquid ejection apparatus and method for controlling liquid ejection apparatus

Abstract

To provide a liquid ejection apparatus capable of suppressing an increase in the size of the liquid ejection apparatus while suppressing a decrease in the detection accuracy of an optical sensor, and to provide a method for controlling the liquid ejection apparatus.SOLUTION: A liquid ejection apparatus includes a medium supporting portion that supports a medium, a liquid ejection head that ejects liquid onto the medium supported by the medium supporting portion, a carriage on which the liquid ejection head is mounted and which moves in a width direction of the medium, an optical sensor that is provided on the carriage to face the medium supported by the medium supporting portion, and a reflection portion that reflects light emitted from the optical sensor. The reflection portion is switchable between an exposed state in which the reflection portion is exposed to face the optical sensor and a shielded state in which the reflection portion is not exposed to face the optical sensor. The liquid ejection head can perform recording on the medium by ejecting the liquid when the carriage is positioned in a recording region in a width direction. The reflection portion is disposed in the recording region.SELECTED DRAWING: Figure 5

Description

[Technical Field]

[0001] The present invention relates to a liquid ejection apparatus and a method for controlling the liquid ejection apparatus. [Background technology]

[0002] For example, Patent Document 1 discloses a liquid ejection device that includes a liquid ejection head that ejects liquid onto a medium and a carriage that is movable in the width direction of the medium with the liquid ejection head mounted on it. In the liquid ejection device, the liquid ejection head moves to a recording area in the width direction, and liquid is ejected from the liquid ejection head, thereby recording an image on the medium.

[0003] In such a liquid ejection device, an optical sensor is mounted on the carriage, and a reflecting section is provided facing the optical sensor. The reflecting section has a reference reflecting surface used to adjust the sensitivity of the optical sensor. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2013-169707 Summary of the Invention [Problem to be solved by the invention]

[0005] However, in such a liquid ejection device, in consideration of the influence of the liquid ejected from the liquid ejection head, the cover part is moved outside the movement area of ​​the carriage to expose the reflecting part. This requires space in the width direction to move the cover part. This could lead to an increase in the size of the liquid ejection device. [Means for solving the problem]

[0006] A liquid ejection device that solves the above problem comprises a medium support unit that supports a medium, a liquid ejection head that ejects liquid onto the medium supported by the medium support unit, a carriage that carries the liquid ejection head and moves in the width direction of the medium, an optical sensor that is provided on the carriage so as to face the medium supported by the medium support unit, and a reflecting unit that reflects light emitted from the optical sensor, wherein the reflecting unit is switchable between an exposed state in which it is exposed so as to face the optical sensor, and a shielded state in which the reflecting unit is not exposed so as to face the optical sensor, and the liquid ejection head is capable of recording on the medium by ejecting liquid when the carriage is positioned in a recording area in the width direction, and the reflecting unit is provided in the recording area.

[0007] A control method for a liquid ejection device that solves the above problem includes a carriage that is equipped with a liquid ejection head that ejects liquid onto a medium supported by a medium support section and that moves in the width direction of the medium, an optical sensor that is provided on the carriage so as to face the medium supported by the medium support section, and a reflecting section that reflects light emitted from the optical sensor, and includes switching between an exposed state in which the reflecting section is exposed so as to face the optical sensor and a shielded state in which the reflecting section is not exposed so as to face the optical sensor in a recording area in which recording can be made on the medium by the liquid ejection head ejecting liquid when the carriage is positioned in the width direction. [Brief explanation of the drawings]

[0008] [Figure 1] FIG. 1 is a perspective view showing a liquid ejection device according to a first embodiment. [Figure 2] FIG. 2 is a perspective view showing the liquid ejection device of the first embodiment. [Figure 3] FIG. 3 is a perspective view showing the liquid ejection device of the first embodiment. [Figure 4] FIG. 4 is a perspective view showing the liquid ejection device of the first embodiment. [Figure 5] FIG. 5 is a top view showing the liquid ejection device of the first embodiment. [Figure 6] FIG. 6 is a top view showing the liquid ejection device of the first embodiment. [Figure 7] FIG. 7 is a side view showing the liquid ejection device of the first embodiment. [Figure 8] FIG. 8 is a side view showing the liquid ejection device of the first embodiment. [Figure 9] FIG. 9 is a block diagram showing the liquid ejection device of the first embodiment. [Figure 10] FIG. 10 is a flowchart showing the detection sensitivity adjustment process according to the first embodiment. [Figure 11] FIG. 11 is a side view showing the liquid ejection device of the second embodiment. [Figure 12] FIG. 12 is a side view showing the liquid ejection device of the second embodiment. [Figure 13] FIG. 13 is a perspective view showing a liquid ejection device according to the third embodiment. [Figure 14] FIG. 14 is a perspective view showing a liquid ejection device according to the third embodiment. [Figure 15] FIG. 15 is a perspective view showing a liquid ejection device according to the fourth embodiment. [Figure 16] FIG. 16 is a perspective view showing a liquid ejection device according to the fourth embodiment. [Figure 17] FIG. 17 is a perspective view showing a liquid ejection device according to the fourth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0009] [First embodiment] An embodiment of a liquid ejection device and a method for controlling a liquid ejection device will be described below. In the following description, the direction intersecting the vertical direction Z is referred to as the width direction X, and the direction intersecting the vertical direction Z and the width direction X is referred to as the front-to-rear direction Y. One of the width directions X is referred to as the first width direction X1, and the other of the width directions X is referred to as the second width direction X2. One of the front-to-rear directions Y is referred to as the front Y1, and the other of the front-to-rear directions Y is referred to as the rear Y2. The upper side of the vertical direction Z is referred to as the upper side Z1, and the lower side of the vertical direction Z is referred to as the lower side Z2. The second width direction X2 corresponds to one example of the width direction X. The first width direction X1 corresponds to the other example of the width direction X.

[0010] <Configuration of liquid ejection device 10> As shown in Figures 1 and 2, a liquid ejection device 10 is a device that records an image on a medium by ejecting a liquid onto the medium. The liquid may be, for example, ink. The liquid may be, for example, a plurality of colors or a single color. The medium may be, for example, paper.

[0011] The liquid ejection device 10 includes a housing 11. The housing 11 is the exterior of the liquid ejection device 10. The housing 11 includes a front surface 11A. The front surface 11A faces forward Y1. The liquid ejection device 10 includes an operation panel 12. The operation panel 12 is provided on a front surface 11A. The operation panel 12 includes an operation unit 12A and a display unit 12B. The operation unit 12A is configured to be operable by a user. The display unit 12B may be configured to emit light in a predetermined color.

[0012] The liquid ejection device 10 includes an opening / closing cover 13. The opening / closing cover 13 is provided on the front surface 11A. The opening / closing cover 13 can be opened and closed relative to the front surface 11A. The opening / closing cover 13 can be moved between a closed position shown in FIG. 1 and an open position shown in FIG. 2.

[0013] As shown in FIG. 2, the liquid ejection device 10 includes a mounting section 14. Media are placed on the mounting section 14 after recording. The mounting section 14 is a paper ejection stacker. The mounting section 14 can be housed within the housing 11. The mounting section 14 is movable in the front-rear direction Y. When the opening / closing cover 13 is in the open position, the mounting section 14 protrudes forward Y1 from the front surface 11A.

[0014] 3 to 6, the liquid ejection device 10 includes a transport unit 15, a medium support unit 16, and a liquid ejection unit 20. The liquid ejection device 10 may also include a maintenance unit 17 and a power transmission unit 18.

[0015] The transport unit 15 is configured to transport the medium in the transport direction. The transport unit 15 is configured to transport the medium fed one sheet at a time from a storage cassette (not shown). In FIG. 3, the transport unit 15 is configured to transport the medium along the forward direction Y1.

[0016] The transport unit 15 includes a plurality of rollers. The plurality of rollers in the transport unit 15 include a drive transport roller 15A and a driven transport roller 15B. The drive transport roller 15A and the driven transport roller 15B are located upstream of the medium support unit 16 in the transport direction. The transport unit 15 includes a drive unit 26 shown in FIG. 9. The drive unit 26 is a drive source that drives the drive transport roller 15A. The drive unit 26 may be a motor.

[0017] The drive transport roller 15A is configured to rotate by power from the drive unit 26. The drive transport roller 15A and the driven transport roller 15B rotate in a nip state that sandwiches the medium, thereby transporting the medium in the transport direction. In this way, the drive transport roller 15A and the driven transport roller 15B are configured to transport the pre-recorded medium to the medium support unit 16 along the transport direction.

[0018] 5 and 6, the transport unit 15 includes a plurality of rollers, namely, a drive discharge roller 15C and a driven discharge roller 15D. The drive discharge roller 15C and the driven discharge roller 15D are located downstream in the transport direction from the medium support unit 16. The drive discharge roller 15C and the driven discharge roller 15D correspond to an example of a discharge unit.

[0019] The drive discharge roller 15C is configured to rotate by power transmitted from the drive unit 26 via the power transmission unit 18. The drive discharge roller 15C and the driven discharge roller 15D rotate in a nip state that sandwiches the medium, thereby transporting the medium in the transport direction. In this way, the drive discharge roller 15C and the driven discharge roller 15D are configured to transport the recorded medium from the medium support unit 16 to the loading unit 14 along the transport direction. In other words, the loading unit 14 is configured to load the recorded medium that has been discharged by the transport unit 15.

[0020] 3 to 6, the medium support section 16 is configured to support a medium. The medium support section 16 is configured to face a liquid ejection head 21 (described later) below Z2 of the liquid ejection section 20. In other words, the medium support section 16 is configured to support a medium onto which liquid is ejected.

[0021] The liquid ejection unit 20 is configured to record an image on a medium by ejecting liquid onto the medium. The liquid ejection unit 20 includes a liquid ejection head 21, a carriage 22, and a carriage support unit 23. In other words, the liquid ejection device 10 includes the liquid ejection head 21, the carriage 22, the carriage support unit 23, and a carriage drive unit 27.

[0022] The liquid ejection head 21 is configured to eject a liquid. The liquid ejection head 21 is configured to eject a liquid onto a medium supported by the medium support section 16. The liquid ejection head 21 is mounted on a carriage 22.

[0023] The carriage 22 is configured to carry the liquid ejection head 21. The carriage 22 is supported by a carriage support portion 23. The carriage support portion 23 extends along the width direction X. The carriage support portion 23 is a guide rail that supports the carriage 22.

[0024] The carriage drive unit 27 is a drive source for moving the carriage 22. The carriage drive unit 27 may be a motor. The carriage 22 is capable of moving along the carriage support unit 23 by power from the carriage drive unit 27. In other words, the carriage 22 is configured to move in the width direction X.

[0025] The carriage 22 is movable between a standby position P21 shown in FIG. 3 and a movement position P22 shown in FIG. 4. The standby position P21 is located closer to the second width direction X2 than a recording area R2 (described later). The movement position P22 is located closer to the first width direction X1 than the recording area R2. In other words, the standby position P21 is located closer to the second width direction X2 than a recording area R2 (described later). The movement position P22 is located closer to the first width direction X1 than the recording area R2. Note that the area of ​​the carriage 22 located at the end of the recording area R2 on the second width direction X2 side and the area of ​​the carriage 22 located at the standby position P21 may partially overlap. The area of ​​the carriage 22 located at the end of the recording area R2 on the first width direction X1 side and the area of ​​the carriage 22 located at the movement position P22 may partially overlap.

[0026] 5, the carriage 22 is movable across a movement region R1. The movement region R1 is an area in the width direction X. The movement region R1 is provided in the width direction X so as to include a recording region R2.

[0027] The recording area R2 is an area in the width direction X. The recording area R2 is an area where recording can be performed on the medium by ejecting liquid onto the medium. The recording area R2 may be an area that is shorter than the width of the medium in the width direction X, an area that is the same as the width of the medium in the width direction X, or an area that is wider than the width of the medium in the width direction X. In this way, the liquid ejection head 21 can record on the medium by ejecting liquid when the carriage 22 is positioned in the recording area R2 in the width direction X.

[0028] The liquid ejection head 21 has a nozzle surface 24. The nozzle surface 24 is provided on the bottom surface of the liquid ejection head 21. The nozzle surface 24 is provided so as to face downward in the direction Z2. The nozzle surface 24 is a surface on which a plurality of nozzles that eject liquid are opened. The nozzle surface 24 is provided on the liquid ejection head 21 so as to face the medium supported by the medium support unit 16.

[0029] The liquid ejection head 21 is provided with an optical sensor 25. That is, the liquid ejection device 10 is provided with the optical sensor 25. The optical sensor 25 is provided on the bottom surface of the liquid ejection head 21. The optical sensor 25 is provided so as to face downward Z2. That is, the optical sensor 25 is provided on the liquid ejection head 21 so as to face the medium supported by the medium support unit 16.

[0030] The optical sensor 25 is located behind the nozzle surface 24 in the Y2 direction. In other words, the optical sensor 25 is located upstream in the transport direction from the nozzle surface 24. The optical sensor 25 may be a sensor that detects the width of the medium. In other words, the optical sensor 25 detects the edge of the medium in the width direction X supported by the medium support unit 16.

[0031] 4, the maintenance unit 17 is configured to perform maintenance on the liquid ejection head 21. The maintenance unit 17 may include a cap that receives liquid from the liquid ejection head 21 as waste liquid. The maintenance unit 17 is provided outside the recording region R2 in the width direction X. The maintenance unit 17 is provided in an area of ​​the movement region R1 on the second width direction X2 side.

[0032] The power transmission unit 18 is configured to transmit power from the drive unit 26 to the drive discharge roller 15C. The power transmission unit 18 includes a power switching unit (not shown). The power switching unit switches whether or not to transmit power from the drive unit 26 to the mounting unit 14. The mounting unit 14 may include a rack (not shown) to which the power from the drive unit 26 is transmitted. In this way, the drive unit 26 can move the mounting unit 14 via the power transmission unit 18 in accordance with the switching of the power switching unit.

[0033] As shown in Figures 5 and 6, the mounting section 14 is movable in the front-rear direction Y. The mounting section 14 is movable between a first position P11 shown in Figure 5 and a second position P12 shown in Figure 6. The first position P11 is a position Y2 rearward of the second position P12. In other words, the second position P12 is a position downstream of the first position P11 in the transport direction. The downstream side in the transport direction corresponds to the ejection direction in which the medium is ejected after recording. The first position P11 is a position where the mounting section 14 is housed in the housing 11. The second position P12 may be a position where the mounting section 14 protrudes from the front surface 11A.

[0034] 5 to 8, the mounting portion 14 includes a reflecting portion 31 and an exposed portion 32. That is, the liquid ejection device 10 includes the reflecting portion 31 and the exposed portion 32. The reflecting portion 31 and the exposed portion 32 are provided on the upper surface of the mounting portion 14. The reflecting portion 31 is provided in the recording region R2. The reflecting portion 31 is provided on the first width direction X1 side relative to the center of the recording region R2 in the width direction X.

[0035] The reflecting portion 31 is configured to reflect light emitted from the optical sensor 25. The reflecting portion 31 is a reference surface for adjusting the sensitivity of the optical sensor 25. The reflecting portion 31 may have any color that has high reflectivity. The reflecting portion 31 is white, but is not limited to this and may be gray, for example.

[0036] The exposed portion 32 is provided in the recording region R2. The exposed portion 32 is provided on the first width direction X1 side relative to the center of the recording region R2 in the width direction X. The exposed portion 32 is located rearward Y2 from the reflecting portion 31. In other words, the exposed portion 32 is located upstream of the reflecting portion 31 in the transport direction.

[0037] The exposed portion 32 has a lower reflectivity than the reflective portion 31. The exposed portion 32 is not a reference surface for adjusting the sensitivity of the optical sensor 25. The exposed portion 32 may have a color that is not erroneously detected as the color of the medium. The exposed portion 32 has a color similar to that of the medium support portion 16, but is not limited to this.

[0038] The medium support part 16 has an opening 16A. The opening 16A is provided in the recording area R2. The opening 16A is provided closer to the first width direction X1 side than the center of the recording area R2 in the width direction X. The opening 16A can expose the top surface of the mounting part 14 through a frame opening 29A of the frame 29. The frame 29 is a member located between the medium support part 16 and the mounting part 14 in the vertical direction Z.

[0039] 7, when the mounting portion 14 is located at the first position P11, the reflecting portion 31 is located at the exposed position P13. The exposed position P13 is a position in the recording region R2 where the reflecting portion 31 is exposed so as to face the optical sensor 25 through the opening 16A and the frame opening 29A. In this way, when the reflecting portion 31 is located at the exposed position P13, it is exposed through the opening 16A.

[0040] 8, when the mounting unit 14 is disposed at the second position P12, the reflecting unit 31 is located at the shielding position P14. The shielding position P14 is a position where the reflecting unit 31 is shielded by the medium support unit 16. In other words, the medium support unit 16 corresponds to an example of a shielding unit that shields the reflecting unit 31.

[0041] The shielding position P14 is a position in the recording region R2 where the exposed portion 32 is exposed through the opening 16A so as to face the optical sensor 25. In this way, the exposed portion 32 is an area that is exposed through the opening 16A when the reflecting portion 31 is disposed at the shielding position P14.

[0042] In this way, the liquid ejection device 10 switches between an exposed state and a blocked state. In the exposed state, the reflecting section 31 is exposed so as to face the optical sensor 25. In the blocked state, the reflecting section 31 is not exposed so as to face the optical sensor 25.

[0043] <Electrical configuration of the liquid ejection device 10> As shown in FIG. 9, the liquid ejection device 10 includes a control unit 30. The control unit 30 is configured to control the liquid ejection device 10. The control unit 30 may be configured with one or more processors. The processor executes various processes according to a computer program. The control unit 30 may be configured with one or more dedicated hardware circuits. The control unit 30 may include an application specific integrated circuit that executes at least some of the various processes. The control unit 30 may be configured with a circuit including a combination of a processor and a hardware circuit. The processor includes a CPU and memory such as RAM and ROM. The memory stores program code or instructions configured to cause the CPU to execute processes. The memory, i.e., computer-readable medium, includes any readable medium accessible by a general-purpose or special-purpose computer.

[0044] The control unit 30 is connected to the operation unit 12A and the display unit 12B. The control unit 30 receives signals from the operation unit 12A. The control unit 30 displays information on the display unit 12B. The control unit 30 is connected to the transport unit 15 and the liquid ejection unit 20. The control unit 30 is configured to control the drive unit 26. The control unit 30 is configured to control the liquid ejection head 21. The control unit 30 is configured to control the optical sensor 25. The control unit 30 is configured to control the carriage drive unit 27.

[0045] <Detection sensitivity adjustment process> The detection sensitivity adjustment process will now be described with reference to Fig. 10. The detection sensitivity adjustment process is executed by the control unit 30 at predetermined intervals.

[0046] As shown in FIG. 10, in step S10, the control unit 30 determines whether or not the startup conditions are met. The startup conditions are conditions that are met when the liquid ejection device 10 is started up. The startup conditions may be conditions that are met when the liquid ejection device 10 is powered on. The startup conditions may be conditions that are met when an initialization instruction is given to the liquid ejection device 10. If the control unit 30 determines that the startup conditions are not met, it ends the detection sensitivity adjustment process. If the startup conditions are met, the control unit 30 proceeds to step S11.

[0047] In step S11, the control unit 30 executes a carriage movement process. In this process, the control unit 30 controls the carriage drive unit 27 to move the carriage 22 from the standby position P21 to the movement position P22.

[0048] In step S12, the control unit 30 executes a reference detection process. In this process, the control unit 30 moves the carriage 22 from the standby position P21 to the movement position P22, and then causes the optical sensor 25 to emit light. With the carriage 22 positioned at the movement position P22, the optical sensor 25 receives reflected light from the reflector 31. The control unit 30 receives from the optical sensor 25 the amount of light received by the optical sensor 25.

[0049] In this case, the mounting portion 14 is disposed at the first position P11. That is, the reflecting portion 31 is disposed at the exposed position P13. As a result, the reflecting portion 31 is exposed through the opening 16A and the frame opening 29A. When the mounting portion 14 is disposed at the second position P12, it is moved to the first position P11 under the control of the control portion 30.

[0050] The control unit 30 moves the carriage 22 from the standby position P21 to the movement position P22, thereby causing the optical sensor 25 to face the reflecting unit 31. As a result, the control unit 30 acquires the amount of light received from the optical sensor 25 as a reference for adjusting the sensitivity of the optical sensor 25.

[0051] In step S13, the control unit 30 executes a detection sensitivity setting process. In this process, the control unit 30 sets the sensitivity of the optical sensor 25 based on the amount of light received from the optical sensor 25. In this way, the control unit 30 adjusts the sensitivity of the optical sensor 25.

[0052] In step S14, the control unit 30 executes a switching process. In this process, the control unit 30 controls the drive unit 26 to drive the drive unit 26 in the forward direction while power is being transmitted from the drive unit 26 to the mounting unit 14. As a result, the control unit 30 moves the mounting unit 14 from the first position P11 to the second position P12. Thereafter, the power switching unit changes from a state in which power from the drive unit 26 is transmitted to the mounting unit 14 to a state in which power from the drive unit 26 is not transmitted to the mounting unit 14.

[0053] As a result, the mounting section 14 moves to the second position P12. That is, the reflecting section 31 moves to the shielding position P14. As a result, the reflecting section 31 is not exposed through the opening 16A and the frame opening 29A, but is shielded by the medium support section 16. Also, the exposed section 32 is exposed through the opening 16A and the frame opening 29A.

[0054] After the detection sensitivity adjustment process is completed, the control unit 30 moves the carriage 22 from the movement position P22 to the standby position P21. Thereafter, the control unit 30 controls the transport unit 15 to transport the medium in the transport direction based on a recording instruction from the user. The control unit 30 controls the liquid discharge unit 20 to record an image on the medium by discharging liquid onto the transported medium. In other words, the detection sensitivity adjustment process is executed before discharging liquid onto the medium.

[0055] In this way, the control unit 30 positions the mounting unit 14 at the first position P11 before ejecting liquid from the liquid ejection head 21 onto the medium, and positions the mounting unit 14 at the second position P12 when ejecting liquid from the liquid ejection head 21 onto the medium.

[0056] Furthermore, when the accommodation condition is met, the control unit 30 controls the drive unit 26 to drive in the reverse direction while power from the drive unit 26 is being transmitted to the placement unit 14. As a result, the control unit 30 moves the placement unit 14 from the second position P12 to the first position P11. The accommodation condition may be met when the power is turned off. The accommodation condition may also be met in response to an instruction from the user.

[0057] In this way, the control unit 30 switches between the exposed state and the blocked state. In particular, the control unit 30 switches to the exposed state by moving the mounting unit 14 to the first position P11 and the reflecting unit 31 to the exposed position P13. The control unit 30 switches to the blocked state by moving the mounting unit 14 to the second position P12 and the reflecting unit 31 to the blocked position P14.

[0058] <Actions and Effects of the First Embodiment> The operation and effects of the first embodiment will be described. (1-1) A reflecting section 31 is provided in the recording region R2. The control section 30 can switch between an exposed state in which the reflecting section 31 is exposed so as to face the optical sensor 25, and a shielded state in which the reflecting section 31 is not exposed so as to face the optical sensor 25. This eliminates the need to provide an area for shielding the reflecting section 31 in the width direction X in order to adjust the detection sensitivity of the optical sensor 25. In addition, it is possible to reduce the impact of the mist of liquid ejected from the liquid ejection head 21 on the reflecting section 31. This makes it possible to prevent the liquid ejection device 10 from becoming larger while suppressing a decrease in the detection accuracy of the optical sensor 25.

[0059] (1-2) By positioning the reflecting unit 31 at the shielding position P14, the reflecting unit 31 is not exposed so as to face the optical sensor 25 through the opening 16A of the medium support unit 16. Therefore, by using the medium support unit 16, the reflecting unit 31 is not exposed. This eliminates the need to provide a separate member to prevent the reflecting unit 31 from being exposed. Therefore, it is possible to prevent the liquid ejection device 10 from becoming larger while suppressing a decrease in the detection accuracy of the optical sensor 25.

[0060] (1-3) When the reflecting portion 31 is disposed at the shielding position P14, the exposed portion 32, which has a lower reflectivity than the reflecting portion 31, is exposed through the opening 16A. Therefore, when a medium with high reflectivity is used, it is possible to improve the accuracy of detecting whether or not the medium is a medium.

[0061] (1-4) The control unit 30 can switch between the exposed state and the covered state by moving the mounting unit 14 between the first position P11 and the second position P12 in the front-rear direction Y. This can prevent the liquid ejection device 10 from becoming larger while also preventing a decrease in the detection accuracy of the optical sensor 25.

[0062] (1-5) The control unit 30 can adjust the detection sensitivity of the optical sensor 25 before discharging liquid from the liquid discharge head 21 onto a medium. In addition, when discharging liquid from the liquid discharge head 21 onto a medium, the influence of the mist of liquid discharged from the liquid discharge head 21 on the reflecting unit 31 can be reduced. Therefore, it is possible to prevent the liquid discharge device 10 from becoming larger while suppressing a decrease in the detection accuracy of the optical sensor 25.

[0063] (1-6) The optical sensor 25 is located upstream in the transport direction from the nozzle surface 24. This configuration reduces the effect on the optical sensor 25 of the mist of liquid ejected from the liquid ejection head 21. Therefore, it is possible to prevent the liquid ejection device 10 from becoming larger while suppressing a decrease in the detection accuracy of the optical sensor 25.

[0064] (1-7) The reflecting portion 31 is exposed on the first width direction X1 side, not on the second width direction X2 side where the maintenance portion 17 is provided. This reduces the impact on the reflecting portion 31 of the mist of liquid ejected from the liquid ejection head 21 when maintenance of the liquid ejection head 21 is performed by the maintenance portion 17. Therefore, it is possible to prevent the liquid ejection device 10 from becoming larger while suppressing a decrease in the detection accuracy of the optical sensor 25.

[0065] [Second embodiment] Next, a second embodiment will be described. In the following description, the same configuration as in the already described embodiment will be omitted or simplified, and only the configuration different from the already described embodiment will be described.

[0066] 11 and 12, in the second embodiment, the liquid ejection device 10 may include a shutter 33. The shutter 33 is separate from the mounting portion 14. The shutter 33 is located between the frame 29 and the mounting portion 14 in the vertical direction Z.

[0067] The shutter 33 has the same function as the exposed portion 32 in the first embodiment. The shutter 33 has a lower reflectance than the reflective portion 31. The shutter 33 may have a color that does not cause erroneous detection as the color of the medium. The shutter 33 has a color similar to that of the medium support portion 16, but is not limited to this.

[0068] The shutter 33 includes a first locking portion 33A. The first locking portion 33A is configured to protrude downward Z2 from the bottom surface of the shutter 33. The first locking portion 33A is provided on the rear Y2 side of the shutter 33.

[0069] The frame 29 includes a first protrusion 29B and a second protrusion 29C. The first protrusion 29B and the second protrusion 29C are configured to protrude downward Z2. The first protrusion 29B and the second protrusion 29C are positioned so as to straddle the frame opening 29A in the front-to-rear direction Y. The first protrusion 29B is positioned rearward Y2 from the frame opening 29A. In other words, the first protrusion 29B is positioned upstream of the frame opening 29A in the conveying direction. The second protrusion 29C is positioned forward Y1 from the frame opening 29A. In other words, the second protrusion 29C is positioned downstream of the frame opening 29A in the conveying direction.

[0070] The placing section 14 includes a second locking section 14A. The second locking section 14A is configured to protrude upward Z1 from the upper surface of the placing section 14. The second locking section 14A is located rearward Y2 from the reflecting section 31. In other words, the second locking section 14A is located upstream of the reflecting section 31 in the conveying direction.

[0071] 11, when the mounting portion 14 is disposed at the first position P11, the shutter 33 is disposed at a position where the rear Y2 end portion thereof abuts against the first protrusion 29B. In this case, the shutter 33 is not exposed from the opening 16A and the frame opening 29A, and is disposed rearward Y2 from the opening 16A and the frame opening 29A.

[0072] As a result, the shutter 33 is positioned so as not to shield the reflecting portion 31. The reflecting portion 31 is positioned so as to face the optical sensor 25 across the opening 16A and the frame opening 29A at the exposed position P13.

[0073] 12, when the mounting portion 14 moves from the first position P11 to the second position P12, the second locking portion 14A comes into contact with the first locking portion 33A from the rear Y2, whereby the shutter 33 moves forward Y1 in conjunction with the movement of the mounting portion 14 forward Y1.

[0074] The shutter 33 is disposed at a position where its end on the front Y1 side abuts against the second protrusion 29C. In this case, the shutter 33 is disposed so as to be exposed from the opening 16A and the frame opening 29A. As a result, the reflecting unit 31 is disposed so as not to face the optical sensor 25 via the opening 16A and the frame opening 29A at the shielding position P14.

[0075] As a result, the shutter 33 is disposed so as to face the optical sensor 25 through the opening 16A and the frame opening 29A. That is, the shutter 33 is exposed through the opening 16A and the frame opening 29A when the mounting unit 14 moves to the second position P12. The reflecting unit 31 is disposed so as not to face the optical sensor 25 through the opening 16A and the frame opening 29A at the shielding position P14.

[0076] Furthermore, when the mounting unit 14 moves to the second position P12, the front Y1 end of the shutter 33 abuts against the second protrusion 29C, causing the second locking portion 14A to climb over the first locking portion 33A. Therefore, as shown in Fig. 12, the first locking portion 33A is positioned at a position Y2 rearward of the second locking portion 14A. As a result, when the mounting unit 14 is positioned at the second position P12, the second locking portion 14A abuts against the first locking portion 33A from the front Y1.

[0077] Furthermore, in conjunction with the movement of the mounting portion 14 from the second position P12 to the first position P11, the shutter 33 moves rearward Y2 from the opening 16A and the frame opening 29A. At this time, the rearward Y2 end of the shutter 33 abuts against the first protrusion 29B, causing the second locking portion 14A to climb over the first locking portion 33A. Therefore, as shown in FIG. 11 , the first locking portion 33A is disposed at a position forward Y1 from the second locking portion 14A.

[0078] [Third embodiment] Next, a third embodiment will be described. 13 and 14, in the third embodiment, the liquid ejection device 10 includes a power switching unit 40. The power switching unit 40 can switch whether or not power is transmitted from the drive unit 26 to the mounting unit 14.

[0079] The power switching unit 40 includes a rotating unit 41. That is, the liquid ejection device 10 includes the rotating unit 41. The rotating unit 41 is provided in the movement region R1. The rotating unit 41 is provided on the first width direction X1 side of the center of the movement region R1. The rotating unit 41 is provided outside the recording region R2 in the movement region R1.

[0080] The rotating unit 41 is attached to a drive roller shaft 15E that extends along the width direction X. The rotating unit 41 is rotatable around the drive roller shaft 15E that extends along the width direction X. A drive conveying roller 15A is axially attached to the drive roller shaft 15E. The driving unit 26 rotates the drive roller shaft 15E. This allows the driving unit 26 to rotate the rotating unit 41.

[0081] The rotating part 41 includes a lever part 42. The lever part 42 protrudes radially from the drive roller shaft 15E. The lever part 42 can switch between transmitting and not transmitting power from the drive part 26 to the mounting part 14.

[0082] The rotating portion 41 includes a protruding portion 43. The protruding portion 43 protrudes in the second width direction X2. The protruding portion 43 includes a reflecting portion 44. The reflecting portion 44 is provided on a first surface of the protruding portion 43. The first surface is located at the tip of the protruding portion 43. In other words, the reflecting portion 44 is located at the tip of the protruding portion 43.

[0083] The rotating part 41 can rotate between a facing position P31 shown in Fig. 13 and a retracted position P32 shown in Fig. 14. The facing position P31 is a position where the reflecting part 44 faces upward Z1. The facing position P31 is a position where the reflecting part 44 faces the optical sensor 25.

[0084] The opposing position P31 is a position where it is possible to switch whether or not power is transmitted from the drive unit 26 to the mounting unit 14. The opposing position P31 is a position where the lever unit 42 protrudes upward Z1. In particular, the opposing position P31 is a position where the carriage 22 abuts against the lever unit 42. In this way, when the rotating unit 41 is disposed at the opposing position P31, the carriage 22 can abut against the lever unit 42.

[0085] The retracted position P32 is a position where the reflecting portion 44 faces the forward Y1. The retracted position P32 is a position where the reflecting portion 44 does not face the optical sensor 25. The retracted position P32 is a position where power is not transmitted from the drive portion 26 to the mounting portion 14. The retracted position P32 is a position where the lever portion 42 protrudes forward Y1. In particular, the retracted position P32 is a position where the carriage 22 does not abut against the lever portion 42. In this way, when the rotating portion 41 is disposed in the retracted position P32, the lever portion 42 does not abut against the carriage 22.

[0086] When the drive roller shaft 15E rotates forward, the rotation of the rotating part 41 is restricted at the retracted position P32. As a result, even if the drive roller shaft 15E rotates forward, the rotating part 41 rotates freely at the retracted position P32 and stops rotating.

[0087] When the drive roller shaft 15E rotates in the reverse direction, the rotation of the rotating part 41 is restricted at the opposing position P31. As a result, even if the drive roller shaft 15E rotates in the reverse direction, the rotating part 41 rotates idly at the opposing position P31 and stops rotating.

[0088] When the rotating unit 41 is in the retracted position P32, the power switching unit 40 does not transmit power from the driving unit 26 to the mounting unit 14. When the rotating unit 41 is in the facing position P31, the power switching unit 40 can switch whether or not to transmit power from the driving unit 26 to the mounting unit 14.

[0089] In particular, when the driving roller shaft 15E rotates in response to the power from the driving unit 26 with the rotating unit 41 positioned at the opposing position P31, the rotating unit 41 rotates idly at the opposing position P31. With the rotating unit 41 positioned at the opposing position P31, the carriage 22 moves in the first width direction X1 while abutting against the lever unit 42, whereby the power from the driving unit 26 is continuously transmitted to the mounting unit 14.

[0090] When the activation condition is met, the control unit 30 may control the drive unit 26 so that the rotating unit 41 rotates to the opposing position P31. When the activation condition is met, the control unit 30 causes the optical sensor 25 to emit light as the carriage 22 moves to the movement position P22, with the rotating unit 41 disposed at the opposing position P31. In this case, the reflecting unit 44 faces the optical sensor 25. The control unit 30 executes a reference detection process and a detection sensitivity setting process.

[0091] Thereafter, the control unit 30 rotates the drive roller shaft 15E in the forward direction with the carriage 22 abutting against the lever unit 42 from the second width direction X2 side. Even when the drive roller shaft 15E rotates in the forward direction, the rotating unit 41 rotates idly due to the abutment with the carriage 22.

[0092] With the rotating unit 41 positioned at the opposing position P31, the carriage 22 moves in the first width direction X1 while abutting against the lever unit 42, which enables the power switching unit 40 to transmit the power of the drive unit 26 to the mounting unit 14. As a result, the mounting unit 14 moves forward Y1 by the power of the drive unit 26, and thereby moves from the first position P11 to the second position P12.

[0093] Thereafter, in the switching process, the control unit 30 moves the carriage 22 from the movement position P22 toward the standby position P21. The control unit 30 controls the drive unit 26 so that the rotating unit 41 rotates to the retracted position P32. The rotating unit 41 is not in contact with the carriage 22, and when the drive roller shaft 15E rotates forward, the rotating unit 41 moves from the facing position P31 to the retracted position P32. In other words, the control unit 30 rotates the rotating unit 41 from the facing position P31 to the retracted position P32.

[0094] The detection sensitivity adjustment process is executed before the liquid is ejected onto the medium. In this way, the control unit 30 places the rotating unit 41 at the facing position P31 before the liquid is ejected onto the medium from the liquid ejection head 21, and places the rotating unit 41 at the retracted position P32 when the liquid is ejected onto the medium from the liquid ejection head 21.

[0095] Furthermore, the control unit 30 may control the drive unit 26 to rotate the rotation unit 41 to the facing position P31 when the storage condition is met. When the storage condition is met, the control unit 30 controls the drive unit 26 to rotate the rotation unit 41 to the facing position P31 while the rotation unit 41 is disposed at the facing position P31. Because the rotation unit 41 is disposed at the facing position P31, the power switching unit 40 can switch whether or not to transmit the power of the drive unit 26 to the platform unit 14. As a result, the platform unit 14 moves rearward Y2 due to the power of the drive unit 26, thereby moving from the second position P12 to the first position P11.

[0096] In this way, the control unit 30 switches between the exposed state and the blocked state. In particular, the control unit 30 switches to the exposed state by moving the rotating unit 41 to the facing position P31 and moving the reflecting unit 44 to a position facing the optical sensor 25. In particular, the control unit 30 switches to the blocked state by moving the rotating unit 41 to the retracted position P32 and moving the reflecting unit 44 to a position not facing the optical sensor 25. In particular, the reflecting unit 44 is configured to move from the facing position P31 to the retracted position P32 around an axis along the width direction X as the rotating unit 41 rotates.

[0097] <Actions and Effects of the Third Embodiment> According to the third embodiment described above in detail, the following effects can be obtained. (3-1) Conventionally, in consideration of the influence of the liquid ejected from the liquid ejection head, a shielding portion is provided to shield the reflecting portion so as to switch between an exposed state and a shielded state. In such cases, a space for providing the shielding portion is required in addition to the space for implementing the conventional function. This may result in an increase in the size of the liquid ejection device.

[0098] Therefore, the liquid ejection device 10 includes a power switching unit 40 that switches whether or not power is transmitted to the mounting unit 14. The reflecting unit 44 is provided in the power switching unit 40. The power switching unit 40 is switchable between an exposed state in which the reflecting unit 44 is exposed to face the optical sensor 25 and a shielded state in which the reflecting unit 44 is not exposed to face the optical sensor 25. This configuration allows the control unit 30 to use the conventional power switching unit 40 to switch the reflecting unit 44 between a position corresponding to the optical sensor 25 and a position not corresponding to the optical sensor 25. This eliminates the need to provide additional space for adjusting the detection sensitivity of the optical sensor 25, separate from the space required for conventional functions. Furthermore, the impact of mist of liquid ejected from the liquid ejection head 21 on the reflecting unit 44 can be reduced. This reduces the size of the liquid ejection device 10 while preventing a decrease in the detection accuracy of the optical sensor 25.

[0099] (3-2) The reflecting unit 44 is configured to move from the facing position P31 to the retracted position P32 around an axis along the width direction X as the rotating unit 41 rotates. With this configuration, the control unit 30 can switch the reflecting unit 44 between a position corresponding to the optical sensor 25 and a position not corresponding to the optical sensor 25 without moving the reflecting unit 44 outside the movement region R1 in which the carriage 22 moves. This eliminates the need to provide a region outside the movement region R1 in the width direction X for moving the reflecting unit 44 to adjust the detection sensitivity of the optical sensor 25. In addition, the impact of the mist of liquid ejected from the liquid ejection head 21 on the reflecting unit 44 can be reduced. Therefore, the liquid ejection device 10 can be prevented from becoming larger while preventing a decrease in the detection accuracy of the optical sensor 25.

[0100] (3-3) The control unit 30 can rotate the reflecting unit 44 between the facing position P31 and the retracted position P32 while moving the mounting unit 14 in the front-rear direction Y using power from the drive unit 26 in accordance with the movement of the carriage 22 in the width direction X. This eliminates the need to provide an area in the width direction X to shield the reflecting unit 44 in order to adjust the detection sensitivity of the optical sensor 25. In addition, it is possible to reduce the impact of the mist of liquid ejected from the liquid ejection head 21 on the reflecting unit 44. This makes it possible to prevent the liquid ejection device 10 from becoming larger while suppressing a decrease in the detection accuracy of the optical sensor 25.

[0101] (3-4) The reflecting unit 44 is provided outside the recording area R2 in the movement area R1. This makes it easier to ensure an area for rotating the reflecting unit 44 around the drive roller shaft 15E along the width direction X. Therefore, it is possible to prevent the liquid ejection device 10 from becoming larger while suppressing a decrease in the detection accuracy of the optical sensor 25.

[0102] [Fourth embodiment] Next, a fourth embodiment will be described. 15 to 17, in the fourth embodiment, the liquid ejection device 10 includes a position adjustment unit 50. The position adjustment unit 50 is configured to adjust the distance between the liquid ejection head 21 and the medium support unit 16 in the vertical direction Z. The position adjustment unit 50 may adjust the height of the carriage support unit 23 in the vertical direction Z, thereby adjusting the distance between the liquid ejection head 21 and the medium support unit 16 in the vertical direction Z.

[0103] The position adjustment unit 50 includes a rotation unit 51. That is, the liquid ejection device 10 includes the rotation unit 51. The rotation unit 51 can switch whether or not to adjust the distance between the liquid ejection head 21 and the medium support unit 16 in the vertical direction Z. In this way, the rotation unit 51 corresponds to an example of a position adjustment switching unit that switches whether or not to cause the position adjustment unit 50 to adjust the distance between the liquid ejection head 21 and the medium support unit 16.

[0104] The rotating unit 51 is provided in the movement region R1. The rotating unit 51 is provided on the first width direction X1 side of the center of the movement region R1. The rotating unit 51 is provided outside the recording region R2 in the movement region R1.

[0105] The rotating unit 51 can rotate around a rotation shaft (not shown) along the width direction X. The rotation shaft rotates in conjunction with the drive roller shaft 15E. This allows the drive unit 26 to rotate the rotating unit 51.

[0106] Rotating portion 51 includes lever portion 52. Lever portion 52 protrudes radially relative to the rotation axis. Lever portion 52 includes reflecting portion 53. Reflecting portion 53 is provided on a first surface of lever portion 52. The first surface is located at the tip of lever portion 52. In other words, reflecting portion 53 is located at the tip of lever portion 52.

[0107] The rotating portion 51 is rotatable between a facing position P41 shown in FIG. 15 and a retracted position P43 shown in FIG. 17, and is also rotatable to an adjustment position P42 shown in FIG. 16. The facing position P41 is a position where the lever portion 52 protrudes forward Y1. The facing position P41 is a position where the reflecting portion 53 faces upward Z1. The facing position P41 is a position where the reflecting portion 53 faces the optical sensor 25. The facing position P41 is a position where the distance between the liquid ejection head 21 and the medium support portion 16 cannot be adjusted.

[0108] The adjustment position P42 is a position between the facing position P41 and the retracted position P43. The adjustment position P42 is a position where the lever portion 52 protrudes upward Z1. The adjustment position P42 is a position where the reflecting portion 53 faces backward Y2. The adjustment position P42 is a position where the reflecting portion 53 does not face the optical sensor 25. The adjustment position P42 is a position where the distance between the liquid ejection head 21 and the medium support portion 16 can be adjusted.

[0109] The retracted position P43 is a position where the reflecting portion 53 faces backward Y2. The retracted position P43 is a position where the lever portion 52 protrudes backward Y2 further than the upper side Z1. The retracted position P43 is a position where the reflecting portion 53 does not face the optical sensor 25. The retracted position P43 corresponds to the shielding position P14. The retracted position P43 is a position where the distance between the liquid ejection head 21 and the medium support portion 16 cannot be adjusted.

[0110] The rotating unit 51 is configured to rotate in reverse as the drive roller shaft 15E rotates in the forward direction. When the drive roller shaft 15E rotates in the forward direction, the rotation of the rotating unit 51 is restricted at the retracted position P43. As a result, even if the drive roller shaft 15E rotates in the forward direction, the rotating unit 51 rotates idly at the retracted position P43 and stops rotating.

[0111] The rotating unit 51 is configured to rotate forward when the drive roller shaft 15E rotates reversely. When the drive roller shaft 15E rotates reversely, the rotation of the rotating unit 51 is restricted at the opposing position P41. As a result, even if the drive roller shaft 15E rotates reversely, the rotating unit 51 idles at the opposing position P41 and stops rotating.

[0112] When the rotating unit 51 is at the facing position P41 or the retracted position P43, the position adjustment unit 50 does not adjust the distance between the liquid ejection head 21 and the medium support unit 16. When the rotating unit 51 is at the adjustment position P42, the position adjustment unit 50 adjusts the distance between the liquid ejection head 21 and the medium support unit 16 in accordance with the movement of the carriage 22 to the movement position P22. The distance between the liquid ejection head 21 and the medium support unit 16 may be adjusted in accordance with the movement distance of the carriage 22.

[0113] When the rotating unit 51 is at the adjustment position P42, the carriage 22 may come into contact with the rotating unit 51 as the carriage 22 moves to the movement position P22, causing the position adjustment unit 50 to adjust the distance between the liquid ejection head 21 and the medium support unit 16. When the rotating unit 51 is at the adjustment position P42, the carriage 22 may come into contact with an abutment portion of the position adjustment unit 50 as the carriage 22 moves to the movement position P22, causing the position adjustment unit 50 to adjust the distance between the liquid ejection head 21 and the medium support unit 16.

[0114] When the activation condition is met, the control unit 30 may control the drive unit 26 so that the rotating unit 51 rotates to the opposing position P41. When the activation condition is met, the control unit 30 causes the optical sensor 25 to emit light as the carriage 22 moves to the movement position P22, with the rotating unit 51 disposed at the opposing position P41. In this case, the reflecting unit 53 faces the optical sensor 25. The control unit 30 executes a reference detection process and a detection sensitivity setting process.

[0115] Thereafter, in the switching process, the control unit 30 controls the drive unit 26 so that the rotating unit 51 rotates to the retracted position P43. As a result, the control unit 30 rotates the rotating unit 51 from the facing position P41 to the retracted position P43.

[0116] In this way, the control unit 30 switches between the exposed state and the blocked state. In particular, the control unit 30 switches to the exposed state by moving the rotating unit 51 to the facing position P41 and moving the reflecting unit 53 to a position facing the optical sensor 25. The control unit 30 switches to the blocked state by moving the rotating unit 51 to the retracted position P43 and moving the reflecting unit 53 to a position not facing the optical sensor 25.

[0117] When the position adjustment condition is met, the control unit 30 controls the drive unit 26 to rotate the rotation unit 51 to the adjustment position P42. The control unit 30 moves the carriage 22 to the movement position P22, thereby causing the position adjustment unit 50 to adjust the distance between the liquid ejection head 21 and the medium support unit 16. The position adjustment condition is met in response to a recording instruction from the user. In other words, the position adjustment condition is met before the liquid ejection head 21 ejects liquid onto the medium. Thereafter, the control unit 30 controls the drive unit 26 to rotate the rotation unit 51 to the retracted position P43.

[0118] In this way, the control unit 30 positions the rotating unit 51 at the facing position P41 or the adjustment position P42 before discharging liquid from the liquid discharge head 21 onto a medium, and positions the rotating unit 51 at the retracted position P43 when discharging liquid from the liquid discharge head 21 onto a medium. In particular, the reflecting unit 53 is configured to move from the facing position P41 to the retracted position P43 around an axis along the width direction X as the rotating unit 51 rotates.

[0119] <Actions and Effects of the Fourth Embodiment> According to the fourth embodiment described above in detail, the following effects can be obtained. (4-1) The liquid ejection device 10 includes a position adjustment unit 50 that adjusts the distance between the liquid ejection head 21 and the medium support unit 16, and a rotation unit 51 that controls whether the position adjustment unit 50 adjusts the distance between the liquid ejection head 21 and the medium support unit 16. The reflecting unit 53 is provided on the rotation unit 51. The rotation unit 51 is switchable between an exposed state in which the reflecting unit 53 is exposed to face the optical sensor 25 and a shielded state in which the reflecting unit 53 is not exposed to face the optical sensor 25. This configuration allows the control unit 30 to use the conventionally installed rotation unit 51 to switch the reflecting unit 53 between a position corresponding to the optical sensor 25 and a position not corresponding to the optical sensor 25. This eliminates the need to provide space for adjusting the detection sensitivity of the optical sensor 25, separate from the space required for conventional functions. Additionally, the impact of mist of liquid ejected from the liquid ejection head 21 on the reflecting unit 53 can be reduced. Therefore, the liquid ejection device 10 can be prevented from becoming larger while preventing a decrease in the detection accuracy of the optical sensor 25.

[0120] (4-2) The reflecting unit 53 is configured to move from the facing position P41 to the retracted position P43 around an axis along the width direction X as the rotating unit 51 rotates. With this configuration, the control unit 30 can switch the reflecting unit 53 between a position corresponding to the optical sensor 25 and a position not corresponding to the optical sensor 25 without moving the reflecting unit 53 outside the movement region R1 in which the carriage 22 moves. This eliminates the need to provide a region outside the movement region R1 in the width direction X for moving the reflecting unit 53 in order to adjust the detection sensitivity of the optical sensor 25. In addition, the impact of the mist of liquid ejected from the liquid ejection head 21 on the reflecting unit 53 can be reduced. Therefore, the liquid ejection device 10 can be prevented from becoming larger while preventing a decrease in the detection accuracy of the optical sensor 25.

[0121] (4-3) The control unit 30 rotates the rotating unit 51 using power from the drive unit 26. This allows the control unit 30 to cause the position adjustment unit 50 to adjust the distance between the liquid ejection head 21 and the medium support unit 16, and to rotate the reflecting unit 53 between the facing position P41 and the retracted position P43. In this way, there is no need to provide an area to shield the reflecting unit 53 in the width direction X in order to adjust the detection sensitivity of the optical sensor 25. In addition, the effect of the mist of liquid ejected from the liquid ejection head 21 on the reflecting unit 53 can be reduced. Therefore, it is possible to prevent the liquid ejection device 10 from becoming larger while suppressing a decrease in the detection accuracy of the optical sensor 25.

[0122] (4-4) The reflecting unit 53 is provided outside the recording unit R2 in the movement region R1. This makes it easier to ensure an area for rotating the reflecting unit 53 around a rotation axis along the width direction X. Therefore, it is possible to prevent the liquid ejection device 10 from becoming larger while suppressing a decrease in the detection accuracy of the optical sensor 25.

[0123] [Example of change] This embodiment can be modified as follows: This embodiment and the following modifications can be combined and implemented within the scope of technical compatibility.

[0124] In the first embodiment, the reflecting portion 31 may be provided on a member different from the mounting portion 14. Unlike the second embodiment, the reflecting portion 31 may be located below the mounting portion 14 in the area Z2. In this case, when the mounting portion 14 is located at the first position P11, the reflecting portion 31 may be exposed so as to face the optical sensor 25 through the opening 16A and the frame opening 29A. When the mounting portion 14 moves from the first position P11 to the second position P12, the reflecting portion 31 does not have to be exposed so as to face the optical sensor 25 through the opening 16A and the frame opening 29A.

[0125] In the first and second embodiments, the opening 16A may include a notch. In the first and second embodiments, the frame 29 may not be provided between the mounting portion 14 and the medium support portion 16. In this case, the frame opening 29A may not be provided.

[0126] In the first and second embodiments, the mounting portion 14 may be located at the second position P12 so as not to protrude from the front surface 11A. In other words, the second position P12 may be located forward Y1 from the first position P11.

[0127] In the first and second embodiments, the drive unit 26 may be provided with a separate drive unit for driving the drive conveyance rollers 15A, a drive unit for driving the drive discharge rollers 15C, and a drive unit for driving the mounting unit 14. In this case, the drive force for driving the drive conveyance rollers 15A or the drive discharge rollers 15C does not need to be transmitted to the mounting unit 14.

[0128] In the first and second embodiments, the placement unit 14 may be movable from the first position P11 to the second position P12 in response to a user operation. The placement unit 14 does not have to move from the first position P11 to the second position P12 in response to control by the control unit 30. In this case, when a start-up condition is met, the control unit 30 may cause the display unit 12B to issue a notification urging the user to move the placement unit 14 from the first position P11 to the second position P12.

[0129] In the first and second embodiments, the placement unit 14 may be movable from the second position P12 to the first position P11 in response to a user operation. The placement unit 14 does not have to move from the second position P12 to the first position P11 in response to control by the control unit 30. In this case, when the storage condition is met, the control unit 30 may cause the display unit 12B to issue a notification urging the user to move the placement unit 14 from the second position P12 to the first position P11.

[0130] In the third and fourth embodiments, the rotating part 41 may be attached to a shaft separate from the drive roller shaft 15E. The rotating part 51 may be attached to the drive roller shaft 15E.

[0131] In the third and fourth embodiments, the driving source for the rotating units 41 and 51 may be separate from the driving source for the drive conveying roller 15A. In other words, the driving unit 26 may be the driving source for the rotating units 41 and 51, but may not be the driving source for the drive conveying roller 15A.

[0132] In the third and fourth embodiments, the reflecting units 44, 53 may be provided separately from the rotating units 41, 51. The reflecting units 44, 53 may be disposed in positions facing the optical sensor 25. In such cases, the rotating units 41, 51 may include a shielding unit that shields the reflecting units 44, 53 so that they do not face the optical sensor 25. This makes it possible for the reflecting units 44, 53 to be switched between an exposed state and a shielded state.

[0133] The control unit 30 may move the reflecting units 31, 44, 53 to positions facing the optical sensor 25 when a start-up condition is met. The control unit 30 may move the reflecting units 31, 44, 53 to positions facing the optical sensor 25 when turning off the power. The control unit 30 may move the reflecting units 31, 44, 53 to positions facing the optical sensor 25 in response to a recording instruction from the user. The control unit 30 may move the reflecting units 31, 44, 53 to positions facing the optical sensor 25 in response to a user instruction different from the recording instruction.

[0134] In response to a recording instruction from the user, the control unit 30 may execute the reference detection process and the detection sensitivity setting process with the reflecting units 31, 44, 53 positioned opposite the optical sensor 25. After executing the reference detection process and the detection sensitivity setting process, the control unit 30 may move the reflecting units 31, 44, 53 to positions not facing the optical sensor 25.

[0135] In response to a user instruction different from the recording instruction, the control unit 30 may execute the reference detection process and the detection sensitivity setting process with the reflecting units 31, 44, 53 positioned opposite the optical sensor 25. After executing the reference detection process and the detection sensitivity setting process, the control unit 30 may move the reflecting units 31, 44, 53 to positions not facing the optical sensor 25.

[0136] The medium may be paper, resin film or sheet, resin-metal composite film, laminate film, textile, nonwoven fabric, metal foil, metal film, ceramic sheet, clothing, etc.

[0137] Any liquid can be selected as long as it can be applied to a medium and record on that medium. For example, ink includes particles of functional materials made of solids such as pigments or metal particles dissolved, dispersed, or mixed in a solvent, and includes various compositions such as water-based ink, oil-based ink, gel ink, and hot-melt ink.

[0138] The liquid ejection device 10 is not limited to an inkjet printer, but may be a dot impact printer. The phrase "at least any" used herein means one or more of the desired options. As an example, when the number of options is two, the phrase "at least any" used herein means only one option or both options. As another example, when the number of options is three or more, the phrase "at least any" used herein means only one option or any combination of two or more options.

[0139] [Note] The technical concepts and their effects that can be understood from the above-described embodiments and modifications will be described below. The technical concepts and their effects can be combined with each other to the extent that they are not technically inconsistent.

[0140] (A) A liquid ejection device includes a medium support unit that supports a medium, a liquid ejection head that ejects liquid onto the medium supported by the medium support unit, a carriage that carries the liquid ejection head and moves in the width direction of the medium, an optical sensor that is provided on the carriage so as to face the medium supported by the medium support unit, and a reflecting unit that reflects light emitted from the optical sensor, wherein the reflecting unit is switchable between an exposed state in which it is exposed so as to face the optical sensor and a shielded state in which the reflecting unit is not exposed so as to face the optical sensor, and the liquid ejection head is capable of recording on the medium by ejecting liquid when the carriage is positioned in a recording area in the width direction, and the reflecting unit is provided in the recording area.

[0141] According to this configuration, a reflecting portion is provided in a recording area of ​​the carriage that can record on a medium by ejecting liquid. The reflecting portion can be switched between an exposed state in which it faces the optical sensor and a shielded state in which it is not exposed and faces the optical sensor. This eliminates the need to provide an area in the width direction to shield the reflecting portion in order to adjust the detection sensitivity of the optical sensor. In addition, it is possible to reduce the impact of mist of liquid ejected from the liquid ejection head on the reflecting portion. Therefore, it is possible to prevent a decrease in the detection accuracy of the optical sensor while also preventing the liquid ejection device from becoming larger.

[0142] (B) The liquid ejection device may further include a control unit that switches the reflecting section between the exposed state and the blocked state. With this configuration, the reflecting section can be controlled to switch between the exposed state and the blocked state.

[0143] (C) In the above liquid ejection device, the medium support unit has an opening, and the opening is provided in the recording area, and the control unit switches to the exposed state by moving the reflecting unit to an exposed position, and switches to the shielded state by moving the reflecting unit to a shielded position, the exposed position being a position in the recording area where the reflecting unit is exposed so as to face the optical sensor through the opening, and the shielded position being a position where the reflecting unit is shielded by the medium support unit.

[0144] According to this configuration, by positioning the reflecting portion in the shielding position, the reflecting portion is not exposed so as to face the optical sensor through the opening of the medium support portion. Therefore, by using the medium support portion, the reflecting portion is not exposed. This eliminates the need to provide a separate member to prevent the reflecting portion from being exposed. Therefore, it is possible to prevent a decrease in the detection accuracy of the optical sensor while also preventing the liquid ejection device from becoming larger.

[0145] (D) In ​​the liquid ejection device, when the reflecting section is disposed at the shielding position, an area having a lower reflectance than the reflecting section may be exposed through the opening. With this configuration, when the reflector is positioned at the shielding position, the area with a lower reflectivity than the reflector is exposed through the opening, thereby improving the accuracy of detecting whether or not a medium with a high reflectivity is used.

[0146] (E) The liquid ejection device includes a transport unit that transports a medium, and a mounting unit that mounts the medium onto which liquid has been ejected from the liquid ejection head and that has been discharged by the transport unit, and the mounting unit is movable between a first position in a discharge direction in which the medium onto which liquid has been ejected from the liquid ejection head is discharged by the transport unit, and a second position that is further in the discharge direction than the first position, and the reflecting unit is provided on the mounting unit, and the control unit may move the reflecting unit to the exposed position by moving the mounting unit to the first position, and move the reflecting unit to the hidden position by moving the mounting unit to the second position.

[0147] With this configuration, the control unit can switch between the exposed state and the covered state by moving the mounting unit between the first position and the second position in the discharge direction, thereby preventing a decrease in the detection accuracy of the optical sensor and preventing an increase in the size of the liquid ejection device.

[0148] (F) The liquid discharge device may include a shutter that is exposed through the opening in response to movement of the placement unit to the second position. This configuration can achieve the same effect as (D).

[0149] (G) In the liquid ejection device, the shutter may have a lower reflectance than the reflecting portion. This configuration can achieve the same effect as (D). (H) In the above liquid ejection device, the control unit may place the placement unit at the first position before ejecting liquid from the liquid ejection head onto a medium, and may place the placement unit at the second position when ejecting liquid from the liquid ejection head onto a medium.

[0150] This configuration allows the detection sensitivity of the optical sensor to be adjusted before the liquid is ejected from the liquid ejection head onto the medium. Additionally, when the liquid is ejected from the liquid ejection head onto the medium, the effect of the mist of the liquid ejected from the liquid ejection head on the reflecting portion can be reduced. Therefore, it is possible to prevent a decrease in the detection accuracy of the optical sensor while also preventing an increase in the size of the liquid ejection device.

[0151] (I) The liquid ejection device may include a transport unit that transports a medium, the liquid ejection head having a nozzle surface on which a plurality of nozzles that eject liquid are opened, and the optical sensor may be located upstream of the nozzle surface in a transport direction in which the medium is transported by the transport unit.

[0152] This configuration reduces the effect of the mist of liquid ejected from the liquid ejection head on the optical sensor, thereby preventing a decrease in the detection accuracy of the optical sensor and preventing the liquid ejection device from becoming larger.

[0153] (J) The liquid ejection device may include a maintenance unit that performs maintenance on the liquid ejection head, the maintenance unit being located outside the recording area in the width direction and in an area on one side of the center in the width direction, and the reflection unit being located on the other side of the center in the width direction of the recording area.

[0154] With this configuration, the reflecting portion is exposed on the other side in the width direction, rather than on one side in the width direction where the maintenance portion is provided. This reduces the impact of mist of liquid ejected from the liquid ejection head on the reflecting portion when maintenance of the liquid ejection head is performed by the maintenance portion. Therefore, it is possible to prevent a decrease in the detection accuracy of the optical sensor while also preventing an increase in the size of the liquid ejection device.

[0155] (K) A control method for a liquid ejection device comprising: a carriage mounted with a liquid ejection head that ejects liquid onto a medium supported by a medium support unit and that moves in the width direction of the medium; an optical sensor provided on the carriage so as to face the medium supported by the medium support unit; and a reflecting unit that reflects light emitted from the optical sensor, the control method including switching, in a recording area where recording can be performed on the medium by the liquid ejection head ejecting liquid when the carriage is positioned in the width direction, between an exposed state where the reflecting unit is exposed so as to face the optical sensor, and a shielded state where the reflecting unit is not exposed so as to face the optical sensor. This configuration can achieve the same effect as (B).

[0156] (L) In the above-described method for controlling a liquid ejection device, the liquid ejection device may include a mounting section for mounting a medium onto which liquid has been ejected from the liquid ejection head, the mounting section having the reflecting section, and the method may include: moving the mounting section to a first position in a discharge direction in which the medium onto which liquid has been ejected from the liquid ejection head is ejected onto the mounting section, thereby moving the reflecting section to an exposed position in which the medium is in the exposed state; and moving the mounting section to a second position in the discharge direction further in the discharge direction than the first position, thereby moving the reflecting section to a shielded position in which the medium is in the shielded state. This configuration can achieve the same effect as (E).

[0157] (M) The method for controlling the liquid ejection device may further include disposing the placement unit at the first position before ejecting liquid from the liquid ejection head onto a medium, and disposing the placement unit at the second position when ejecting liquid from the liquid ejection head onto a medium. This configuration can achieve the same effect as (H). [Explanation of symbols]

[0158] P11...first position, P12...second position, P13...exposed position, P14...shielded position, P21...standby position, P22...moving position, P31...facing position, P32...retracted position, P41...facing position, P42...adjustment position, P43...retracted position, R1...moving area, R2...recording area, X...width direction, X1...first width direction, X2...second width direction, Y...front-rear direction, Y1...front, Y2...rear, Z...vertical direction, Z1...upper, Z2...lower, 10...liquid ejection device, 11...casing, 11A...front, 12...operation panel, 12A...operation unit, 12B...display unit, 13...opening / closing cover, 14...placing unit, 14A...second locking unit, 15...conveying unit, 15A...driving conveying roller, 15B...following conveying roller, 15C...driving discharge roller roller, 15D...driven discharge roller, 15E...drive roller shaft, 16...medium support portion, 16A...opening, 17...maintenance portion, 18...power transmission portion, 20...liquid ejection portion, 21...liquid ejection head, 22...carriage, 23...carriage support portion, 24...nozzle surface, 25...optical sensor, 26...drive portion, 27...carriage drive portion, 29...frame, 29A...frame opening, 29B...first protrusion portion, 29C...second protrusion portion, 30...control portion, 31...reflecting portion, 32...exposing portion, 33...shutter, 33A...first locking portion, 40...power switching portion, 41...rotating portion, 42...lever portion, 43...protrusion portion, 44...reflecting portion, 50...position adjustment portion, 51...rotating portion, 52...lever portion, 53...reflecting portion.

Claims

1. a medium support section that supports the medium; a liquid ejection head that ejects liquid onto the medium supported by the medium support section; a carriage that carries the liquid ejection head and moves in the width direction of the medium; an optical sensor provided on the carriage so as to face the medium supported by the medium support section; a reflecting portion that reflects light emitted from the optical sensor; Equipped with the reflecting portion is switchable between an exposed state in which the reflecting portion is exposed so as to face the optical sensor and a shielded state in which the reflecting portion is not exposed so as to face the optical sensor, the liquid ejection head is capable of recording on a medium by ejecting liquid when the carriage is positioned in a recording area in the width direction, the reflective portion is provided in the recording area, A liquid ejection device characterized by:

2. The liquid ejection device according to claim 1 , a control unit that switches the reflector between the exposed state and the shielded state, A liquid ejection device characterized by:

3. 3. The liquid ejection device according to claim 2, the medium support portion has an opening; the opening is provided in the recording area, the control unit switches to the exposed state by moving the reflector to an exposed position, and switches to the shielded state by moving the reflector to a shielded position; the exposed position is a position in the recording area where the reflecting portion is exposed to face the optical sensor through the opening, the shielding position is a position where the reflecting portion is shielded by the medium support portion; A liquid ejection device characterized by:

4. The liquid ejection device according to claim 3, When the reflecting portion is disposed at the shielding position, a region having a lower reflectance than the reflecting portion is exposed through the opening. A liquid ejection device characterized by:

5. The liquid ejection device according to claim 3, a transport unit that transports the medium; a placement unit for placing the medium onto which liquid has been ejected from the liquid ejection head and which has been discharged by the transport unit; Equipped with the placement unit is movable between a first position in a discharge direction in which the medium onto which the liquid has been discharged from the liquid discharge head is discharged by the transport unit, and a second position which is further in the discharge direction than the first position, the reflecting portion is provided on the placing portion, the control unit moves the reflecting unit to the exposed position by moving the placement unit to the first position, and moves the reflecting unit to the hidden position by moving the placement unit to the second position. A liquid ejection device characterized by:

6. 6. The liquid ejection device according to claim 5, a shutter that is exposed through the opening in response to movement of the placement unit to the second position; A liquid ejection device characterized by:

7. 7. The liquid ejection device according to claim 6, The shutter has a lower reflectance than the reflecting portion. A liquid ejection device characterized by:

8. 6. The liquid ejection device according to claim 5, the control unit places the placement unit at the first position before the liquid is ejected from the liquid ejection head onto the medium, and places the placement unit at the second position when the liquid is ejected from the liquid ejection head onto the medium. A liquid ejection device characterized by:

9. The liquid ejection device according to any one of claims 1 to 8, a conveying unit that conveys the medium; the liquid ejection head has a nozzle surface on which a plurality of nozzles for ejecting liquid are opened; the optical sensor is located upstream of the nozzle surface in a transport direction in which the medium is transported by the transport unit; A liquid ejection device characterized by:

10. The liquid ejection device according to any one of claims 1 to 8, a maintenance unit that performs maintenance on the liquid ejection head, the maintenance section is provided on the outer side of the recording area in the width direction and on one side of the center in the width direction, the reflective portion is provided on the other side in the width direction of the recording area relative to the center in the width direction; A liquid ejection device characterized by:

11. A method for controlling a liquid ejection device comprising: a carriage that is mounted with a liquid ejection head that ejects liquid onto a medium supported by a medium support unit and that moves in a width direction of the medium; an optical sensor that is provided on the carriage so as to face the medium supported by the medium support unit; and a reflecting unit that reflects light emitted from the optical sensor, In a recording area where recording can be performed on a medium by discharging liquid from the liquid discharge head when the carriage is positioned in the width direction, the recording area includes switching between an exposed state in which the reflecting portion is exposed so as to face the optical sensor and a shielded state in which the reflecting portion is not exposed so as to face the optical sensor. A method for controlling a liquid ejection device.

12. The method for controlling a liquid ejection device according to claim 11, the liquid ejection device includes a mounting portion for mounting a medium onto which liquid has been ejected from the liquid ejection head; the mounting portion has the reflecting portion, moving the placement unit to a first position in a discharge direction in which the medium onto which liquid has been discharged from the liquid discharge head is discharged onto the placement unit, thereby moving the reflection unit to an exposed position where the reflection unit is in the exposed state; and moving the placement unit in the ejection direction from the first position to a second position in the ejection direction, thereby moving the reflection unit to a shielding position in which the reflection unit is in the shielded state. A method for controlling a liquid ejection device.

13. 13. The method for controlling a liquid ejection device according to claim 12, placing the placement unit at the first position before discharging liquid from the liquid discharge head onto a medium; disposing the placement section at the second position when discharging liquid from the liquid discharge head onto a medium; A method for controlling a liquid ejection device.

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