Recording device

Abstract

To provide a recording device for simply adjusting ink attachment positions by a plurality of recording heads.SOLUTION: A recording device 1 includes a plurality of recording heads H for discharging ink onto a recording medium P and performing recording on the recording medium P, a carriage 11 mounted with the plurality of recording heads H, a reference part R1 provided at a position capable of facing the plurality of recording heads H, a distance sensor S which is provided on any one of the plurality of recording heads H and the reference part R1 and measures a distance between the plurality of recording heads H and the reference part R1, and a control part 118 for controlling execution of predetermined processing on the basis of the measurement result of the distance sensor S, and adjusting ink attachment positions of ink discharged from the individual recording heads H.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a recording apparatus. [Background technology]

[0002] Conventionally, there has been known a recording device equipped with a sensor that measures the distance between a recording head and a recording medium. For example, Patent Document 1 discloses a recording device that measures the distance between a recording medium and a recording unit by an acoustic distance sensor. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2016-88022 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, the recording device described in Patent Document 1 has a problem that when multiple recording heads are mounted on a carriage, the height of each recording head with respect to the platen is likely to vary. More specifically, when the recording device is transported or installed, the height may be shifted, causing variation. When the height varies, it becomes difficult for ink ejected from each recording head to adhere to the desired adhesion position, and the quality of the printed image may deteriorate. In addition, there is also a problem that it takes effort to adjust the height after transporting the recording device or replacing the recording head. In other words, there has been a demand for a recording device that can easily adjust the adhesion position of liquid by multiple recording heads. [Means for solving the problem]

[0005] The recording device is characterized by comprising a plurality of recording heads that perform recording by ejecting liquid onto a recording medium, a carriage carrying the plurality of recording heads, a reference unit that is provided in a position capable of facing the plurality of recording heads, a measurement unit that is provided on either the plurality of recording heads or the reference unit and that measures the distance between the plurality of recording heads and the reference unit, and a control unit that controls the execution of a predetermined process based on the measurement results of the measurement unit and adjusts the deposition position of the liquid ejected by each of the recording heads. [Brief description of the drawings]

[0006] [Figure 1] FIG. 1 is a schematic side view showing the configuration of a recording apparatus according to a first embodiment. [Diagram 2] FIG. 2 is a plan view showing the configuration of a recording head. [Diagram 3] FIG. 2 is a side view showing the configuration of a recording head. [Figure 4] FIG. 4 is a schematic plan view showing the arrangement of a recording head and a reference portion. [Diagram 5] FIG. [Figure 6] FIG. 11 is a schematic plan view showing the arrangement of a recording head and a reference portion according to a second embodiment. [Figure 7] FIG. 11 is a schematic plan view showing the arrangement of a recording head and a reference portion according to a third embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0007] In the embodiment described below, a large format recording apparatus used for printing signs and the like will be illustrated and described with reference to the drawings.

[0008] In each of the following figures, XYZ axes are added as mutually orthogonal coordinate axes as necessary, the direction indicated by each arrow is the + direction, and the direction opposite the + direction is the - direction. The Y axis runs along the front-to-back direction of the recording device, with the +Y direction of the recording device being the front. The X axis runs along the left-to-right direction of the recording device, with the +X direction of the recording device being the right. The +X and -X directions along the X axis are sometimes collectively referred to simply as the X direction. The Z axis is a virtual axis that runs vertically, with the +Z direction of the recording device being the upward direction. Note that for ease of illustration, the sizes of each component are different from the actual size.

[0009] 1. First embodiment As shown in FIG. 1, the recording device 1 according to this embodiment includes multiple recording heads H, a carriage 11, and a platen 3. The multiple recording heads H perform recording by ejecting ink, which is a liquid, onto a recording medium P supported by the platen 3. Although not shown, the recording device 1 also includes a measurement unit and a control unit. Note that the description of FIG. 1 will be given from a side view from the +X direction unless otherwise specified. Also, for convenience of illustration, FIG. 1 shows only one of the multiple recording heads H.

[0010] A plurality of recording heads H are mounted on the lower surface of the carriage 11 facing in the -Z direction. Each recording head H has a nozzle surface F in the -Z direction. Nozzles, which will be described later, are provided on the nozzle surface F. Ink droplets are ejected from the nozzles.

[0011] Each of the multiple recording heads H has an adjustment unit (not shown). Each recording head H is mounted on the carriage 11 via the adjustment unit. The adjustment unit adjusts the distance between a reference unit provided on the platen 3 and the recording head H. The reference unit will be described later. The adjustment unit employs a mechanism that converts rotational motion into linear motion, such as a ball screw or a stepless eccentric cam. Specifically, with a ball screw, the height can be adjusted by rotating the screw shaft.

[0012] Each recording head H is connected to a pipe extending from an ink tank (not shown). The ink tanks store color inks of various colors and white ink separately. The ink tanks may also store treatment liquids such as a pretreatment agent and a coating liquid. In this specification, the above-mentioned inks, treatment liquids, and other liquids are collectively referred to as ink.

[0013] When the recording device 1 performs recording, the nozzle surfaces F of the multiple recording heads H are disposed opposite the platen 3 via the recording medium P. The recording heads H are inkjet heads that are driven to eject ink by piezoelectric elements. The means for driving the recording heads H to eject ink is not limited to piezoelectric elements.

[0014] The carriage 11 is disposed facing the platen 3. The carriage 11 moves back and forth in the X direction relative to the recording medium P by a carriage drive unit (not shown). In other words, the carriage 11 is scanned in the X direction that intersects with the +Y direction, which is the transport direction in which the recording medium P is transported on the platen 3. The carriage drive unit applies a driving force for reciprocating movement to the carriage by a carriage motor (described later). The position of the carriage 11 in the X direction is detected by an encoder provided in the carriage drive unit.

[0015] The recording device 1 includes a sending section 14, support sections 2 and 4, a conveying section 9, a platen 3, and a winding section 15 as a conveying and supporting mechanism for the recording medium P. In the sending section 14, the roll-shaped recording medium P before recording is unwound and conveyed to the platen 3. In the winding section 15, the recording medium P after recording is wound into a roll. In other words, the recording device 1 is configured to be capable of recording on a roll-shaped recording medium P. The form of the recording medium P is not limited to being in a roll shape, and may be in a single sheet shape. The recording device 1 may also be a flatbed type in which recording is performed without conveying the recording medium P.

[0016] The recording medium P is transported from the delivery unit 14 by the transport unit 9. At this time, the roll-shaped recording medium P is rotated, for example, in a rotation direction C on the platen 3 so that the recording surface 16 faces upward and is unwound.

[0017] The recording medium P, which has been unwound and transported upward from the delivery section 14, reaches the support section 2. The support section 2 has an area in contact with the recording medium P formed in an arc shape. The recording medium P is transported in the transport direction A while in contact with the area of ​​the support section 2. As a result, the recording medium P reaches the transport section 9.

[0018] The transport unit 9 includes a drive roller 5 and a driven roller 6. The drive roller 5 and the driven roller 6 are disposed between the support unit 2 and the platen 3. The driven roller 6 is located above the drive roller 5. The drive roller 5 and the driven roller 6 are cylindrical, and each of their rotation axes is aligned with the X-axis.

[0019] The driving roller 5 and the driven roller 6 rotate with the recording medium P sandwiched therebetween, thereby transporting the recording medium P in the +Y direction. More specifically, the driving roller 5 and the driven roller 6 unwind and pull out the rolled recording medium P from the delivery unit 14, and transport it to the platen 3 via the support unit 2. The driving roller 5 rotates in a counterclockwise rotation direction C by the drive of a transport motor, which will be described later. The driven roller 6 rotates clockwise in response to the rotation of the driving roller 5. As a result, the recording medium P reaches the platen 3.

[0020] The platen 3 has an upper surface formed in a flat plate shape. The recording medium P is transported in the +Y direction while being supported on the upper surface of the platen 3. As described above, ink droplets are deposited on the recording medium P from the multiple recording heads H on the platen 3. At this time, the multiple recording heads H are scanned in the direction along the X axis, and the recording medium P is transported in the +Y direction. Therefore, the multiple recording heads H can scan in the direction along the X axis relatively to the recording medium P, and can move in the direction along the Y axis relatively to the recording medium P. As a result, an image, text, pattern, etc. is formed and recorded on the recording medium P. The recording medium P reaches the support unit 4 from the platen 3.

[0021] The support part 4 is disposed in the +Y direction of the platen 3. The +Y direction of the support part 4 is inclined downward. Due to the inclination of the support part 4, the support part 4 guides the transport direction of the recording medium P from the +Y direction to the transport direction B. A winding part 15 is provided at the end of the inclination of the support part 4.

[0022] The winding unit 15 is driven by a motor (not shown) to rotate, for example, in a rotation direction C, and winds up the recording medium P in a roll.

[0023] As shown in Figs. 2 and 3, a distance sensor S is disposed on the recording head H as a measurement unit. That is, the distance sensor S is provided on each recording head H. The distance sensor S measures the distance between each of the multiple recording heads H and a reference unit on the platen 3, which will be described later. Note that the distance sensor S is not limited to being provided on the recording head H. The distance sensor S may be provided on either the multiple recording heads H or the reference unit provided on the platen 3. The arrangement of the distance sensor S in the recording device 1 will be described later.

[0024] In plan view from the -Z direction, the recording head H is substantially rectangular, and a substantially rectangular nozzle surface F is provided in the center of the recording head H. In side view from the +X direction, the nozzle surface F protrudes in the -Z direction.

[0025] On the nozzle surface F, four nozzle rows 211a, 211b, 211c, and 211d are arranged in this order toward the +X direction. Each of the nozzle rows 211a, 211b, 211c, and 211d extends along the Y axis. Each of the nozzle rows 211a, 211b, 211c, and 211d is made up of a plurality of nozzles 201. Droplets of the corresponding type of ink are ejected from each of the nozzles 201 in the nozzle rows 211a, 211b, 211c, and 211d. The nozzle rows arranged on the nozzle surface F are not limited to the above configuration.

[0026] The distance sensor S is provided in the recording head H at the center in the direction along the Y axis, which is the transport direction of the recording medium P on the platen 3, and between the nozzle rows 211b and 211c. In other words, in a plan view from the -Z direction, the distance sensor S is located near the intersection of two diagonals of the approximately rectangular nozzle surface F.

[0027] This makes it possible to suppress the effect of the alignment of the carriage 11 with respect to the platen 3 in measuring the distance between the recording head H and the reference portion by the distance sensor S. More specifically, depending on the support form of the carriage 11, the nozzle surface F of the recording head H may be tilted with respect to the upper surface of the platen 3. Even in this case, by arranging the distance sensor S at the center in the transport direction of the recording medium P, it is possible to measure the distance between the recording head H and the reference portion while suppressing the effect of the tilt. Also, since the distance sensor S is provided facing downward like the nozzle surface F of the recording head H, foreign matter such as dust is less likely to adhere to the distance sensor S, and the performance of the distance sensor S can be maintained.

[0028] The distance sensor S is a non-contact distance measuring device. Examples of the distance sensor S include an optical type, a sonic type, and an ultrasonic type. In this embodiment, an ultrasonic sensor including a thin film piezoelectric element described below is used as the distance sensor S.

[0029] The ultrasonic sensor includes a substrate having an opening penetrating through the substrate in the thickness direction, a diaphragm that covers the opening, a thin-film piezoelectric element provided on the rear surface of the diaphragm at a position corresponding to the opening, and an elastic layer that is located inside the opening and faces the thin-film piezoelectric element via the diaphragm. The vibration area of ​​the diaphragm and the thin-film piezoelectric element form one ultrasonic transducer.

[0030] In the ultrasonic sensor, a pulse voltage of a predetermined frequency is applied between two electrodes of the thin-film piezoelectric element, causing the thin-film piezoelectric element to bend and vibrate the vibration area, transmitting ultrasonic waves from the opening. When ultrasonic waves propagating toward the ultrasonic sensor vibrate the vibration area of ​​the diaphragm, a potential difference is generated between the two electrodes of the thin-film piezoelectric element. By detecting this potential difference, it is possible to detect the timing of ultrasonic oscillation and reception. Furthermore, the distance sensor S includes a temperature and humidity sensor, and calculates the speed of sound from the measured temperature and humidity. The temperature and humidity sensor does not need to be located in the same position as the distance sensor S.

[0031] With the above configuration, it is possible to measure the distance between the ultrasonic sensor and the measurement object by transmitting ultrasonic waves to the measurement object and receiving the ultrasonic waves reflected by the measurement object. Note that the ultrasonic sensor of this embodiment is a small ultrasonic sensor specialized for use when the object is located at a short distance.

[0032] Ultrasonic sensors including thin-film piezoelectric elements can improve spatial resolution in distance measurement compared to ultrasonic sensors that do not use thin-film piezoelectric elements. In addition, they are easier to miniaturize compared to optical and sonic sensors. This makes the distance sensor S small and lightweight, making it easy to mount on the recording head H. Furthermore, ultrasonic sensors have the advantage of being less affected by the color and surface reflectance of the measurement target compared to optical sensors.

[0033] As shown in Fig. 4, the platen 3 includes platens 3A and 3B adjacent to each other. In Fig. 4, the carriage 11 and other components are indicated by dashed lines, and the vicinity of the boundary between the platens 3A and 3B in the +X direction within the range scanned by the carriage 11 is illustrated in an enlarged manner. In the following explanation of Fig. 4, unless otherwise specified, a plan view from above will be described.

[0034] Platen 3A is a transport path along which a recording medium P (not shown) is transported. In other words, the range of platen 3A in the direction along the X axis is also the range scanned by carriage 11 during recording by recording device 1. Platen 3B is disposed outside platen 3A in the +X direction, which is the transport path along which recording medium P is transported. The boundary between platens 3A and 3B extends along the Y axis. Platen 3B is not limited to being disposed in the +X direction relative to platen 3A, and may be disposed in the -X direction.

[0035] The carriage 11 is mounted with recording heads H1, ..., H8 as a plurality of recording heads H. Distance sensors S1, ..., S8 as distance sensors S are provided corresponding to the recording heads H1, ..., H8, respectively. The plurality of recording heads H and the plurality of distance sensors S are each disposed on imaginary straight lines L1 to L6 along the X-axis.

[0036] In detail, recording head H1 and distance sensor S1 are disposed on imaginary line L1. Recording head H2 and distance sensor S2 are disposed on imaginary line L2. Recording heads H3, H4 and distance sensors S3, S4 are disposed on imaginary line L3. Recording heads H5, H6 and distance sensors S5, S6 are disposed on imaginary line L4. Recording head H7 and distance sensor S7 are disposed on imaginary line L5. Recording head H8 and distance sensor S8 are disposed on imaginary line L6.

[0037] Of the multiple recording heads H, the recording heads H1, H4, and H7, and the recording heads H2, H3, and H8 are aligned in the direction along the Y axis. The number and arrangement of the multiple recording heads H and the multiple distance sensors S are not limited to the above-mentioned form.

[0038] The reference part R1 is a generally rectangular shape that is elongated in the direction along the Y axis. The reference part R1 is on the platen 3B, and is provided, for example, between the platen 3A and a maintenance position of the carriage 11 in the recording device 1. The reference part R1 is provided outside the transport path of the recording medium P, and is therefore unlikely to come into contact with the recording medium P. This makes it possible to prevent adhesion of dust and the like originating from the recording medium P, and to keep the reference part R1 clean. The reference part R1 is not limited to a generally rectangular shape that is elongated in the direction along the Y axis, and may be divided in the Y axis direction and disposed in a generally rectangular region that is elongated in the direction along the Y axis.

[0039] The carriage 11 can move up to an area including the reference portion R1. When the carriage 11 passes over the platen 3A and is scanned in the +X direction, each distance sensor S faces the reference portion R1. The distance between each recording head H and the reference portion R1 is measured by facing the two in a direction along the Z axis. As the carriage 11 is scanned in the X direction, the reference portion R1 faces each recording head H in sequence. At this time, the distance between each recording head H and the reference portion R1 is measured in sequence.

[0040] The distance sensor S is not limited to being provided on each recording head H. The distance sensor S may be provided on the reference part R1 corresponding to the recording head H. That is, instead of the distance sensors S1 to S8, a plurality of distance sensors S11 to S16 may be provided on the reference part R1 as the distance sensor S. In detail, in the reference part R1, the distance sensor S11 may be disposed on the imaginary straight line L1, the distance sensor S12 on the imaginary straight line L2, the distance sensor S13 on the imaginary straight line L3, the distance sensor S14 on the imaginary straight line L4, the distance sensor S15 on the imaginary straight line L5, and the distance sensor S16 on the imaginary straight line L6 may be disposed.

[0041] The carriage 11 can move to a position facing the reference part R1. By scanning the carriage 11 in the X direction, it becomes possible for the recording heads H3 and H4 to share the distance sensor S13, and for the recording heads H5 and H6 to share the distance sensor S14. In this way, in the carriage 11, the multiple recording heads H arranged on a straight line along the scanning direction can share the distance sensor S provided at the reference part R1. This makes it possible to reduce the number of distance sensors S.

[0042] As shown in FIG. 5, the control unit 118 includes a central processing unit (CPU) 119, a system bus 120, a read only memory (ROM) 121, a random access memory (RAM) 122, a head driving unit 123, a motor driving unit 124, and an input / output unit 130.

[0043] The CPU 119 is responsible for the overall control of the recording device 1. The CPU 119 is electrically connected to a ROM 121, a RAM 122, and a head driving unit 123 via a system bus 120. The ROM 121 stores various control programs and maintenance sequences executed by the CPU 119. The RAM 122 temporarily stores data. The head driving unit 123 drives the multiple recording heads H, namely, recording heads H1, H2, ..., H8.

[0044] The CPU 119 is electrically connected to a motor driving unit 124 via a system bus 120. The motor driving unit 124 is electrically connected to the carriage motor 65, the transport motor 88, and the lift drive motor 99.

[0045] The carriage motor 65 is included in the carriage drive unit described above. The carriage motor 65 moves the carriage 11 back and forth in the X direction. The transport motor 88 drives the drive roller 5 described above to transport the recording medium P. The lift drive motor 99 moves the carriage 11 in the direction along the Z axis. This causes the distances between the multiple recording heads H and the platen 3 and recording medium P to be changed uniformly.

[0046] The CPU 119 is electrically connected to an input / output unit 130 via a system bus 120. The input / output unit 130 is electrically connected to distance sensors S1, S2, ..., S8, which are measurement units, and a PC (Personal Computer) 129. The PC 129 is an information device that inputs recording data and the like to the recording device 1. Note that the above-mentioned distance sensors S11 to S16 may be used instead of the distance sensors S1 to S8.

[0047] The distance sensor S includes distance sensors S1, S2, ..., S8 corresponding to each of the recording heads H1, H2, ..., H8 which are the multiple recording heads H. Each of the distance sensors S1, S2, ..., S8 measures the distance between the corresponding recording head H1, H2, ..., H8 and the reference portion R1 described above, i.e., the height of each recording head H with respect to the platen 3.

[0048] The height of each recording head H is measured before the recording device 1 is shipped. The height is also measured at any time after shipment, such as after the recording device 1 is transported, installed, used for a certain period of time, and after the recording head H is replaced. Information including the measured height of each recording head H is sent to the control unit 118 and stored in the RAM 122. In particular, the information before the recording device 1 is shipped is for an initial state in which the height of each recording head H is adjusted in advance. The information is stored in the RAM 122 of the control unit 118 as initial information on the distance between each recording head H and the reference part R1.

[0049] The control unit 118 executes a predetermined process based on the height information of each recording head H, which is a measurement result of the distance sensor S. The predetermined process of the control unit 118 adjusts the deposition position of the ink ejected from each recording head H1, H2, ..., H8. Note that the height information of each recording head H from the distance sensor S does not include the thickness of the recording medium P. The adjustment for the thickness of the recording medium P may be performed by raising and lowering the carriage 11 by the lifting drive motor 99.

[0050] The predetermined process in the control unit 118 may be executed based on the initial information of the distance and the measurement result of the height of each recording head H at any time after shipment. In this way, the measurement result at any time is compared with the initial information by referring to the stored initial information. If there is a difference between the two, the ink deposition position can be easily adjusted by performing a correction to reduce the difference as the predetermined process.

[0051] The predetermined processing by the control unit 118 includes, as a software adjustment, correcting at least one of the ejection timing and the ejection speed of ink droplets in each recording head H. The predetermined processing also includes adjustment by the adjustment unit, which is a mechanical adjustment, and support when the adjustment is performed manually.

[0052] First, the software adjustment of the above-mentioned predetermined processing will be described. For example, the ROM 121 stores in advance a plurality of ejection conditions such as the ejection timing and ejection speed of ink droplets corresponding to the distance between the reference portion R1 and each recording head H. The control unit 118 reads out the above-mentioned ejection conditions corresponding to the measured height of each recording head H from the ROM 121. Next, the control unit 118 corrects the ejection timing and ejection speed of ink droplets based on the above-mentioned ejection conditions, and controls the head driving unit 123 via the system bus 120.

[0053] The adjustment of the ejection timing includes correction of the ejection timing of ink droplets from each print head H that is scanned together with the carriage 11 during printing. This corrects the microscopic positions at which ink droplets adhere to the printing medium P. The adjustment of the ejection speed includes correction of the ejection speed of ink droplets from each print head H that is scanned during printing. This corrects the microscopic positions at which ink droplets adhere to the printing medium P.

[0054] As described above, the ejection timing and ejection speed of ink droplets are corrected as software adjustments, and the deposition positions of ink droplets can be easily adjusted.

[0055] Next, the mechanical adjustment of the above-mentioned predetermined processing will be described. For example, the difference between the initial information stored in the RAM 122 and the measurement result of the distance between the reference part R1 and each recording head H is mechanically eliminated by the adjustment unit. That is, as the above-mentioned predetermined processing, the adjustment unit is controlled to automatically adjust the distance between the reference part R1 and each recording head H to return to the initial state. When a ball screw or an eccentric cam is used as the adjustment unit, it is rotated by a motor (not shown) controlled by the control unit 118. This makes it possible to easily adjust the ink deposition position on the recording medium P. In addition, when performing automatic adjustment, both software adjustment and mechanical adjustment may be performed. For example, adjustment up to a predetermined range may be corrected by software adjustment, and adjustment beyond the predetermined range may be performed by mechanical adjustment.

[0056] The above mechanical adjustment may be performed manually. Specifically, the control unit 118 may notify adjustment information for adjusting the distance between the reference portion R1 and each recording head H by the adjustment unit in the manual adjustment via the adjustment unit.

[0057] The adjustment information may include information on the difference between the initial information stored in the RAM 122 and the measurement results of the distance between the reference portion R1 and each recording head H, guidance information on the appropriate adjustment amount in the adjustment portion, and information indicating that the appropriate adjustment has been completed. Examples of the notification means include a display on a display panel (not shown) provided in the recording device 1 or a display on the PC 129, a notification sound, a voice, and an indicator light.

[0058] This eliminates the need to measure the distance between the reference portion R1 and each recording head H using a gap gauge or the like each time, and makes it easier to adjust the ink deposition position on the recording medium P.

[0059] It is preferable that the adjustment information is updated sequentially at a predetermined time interval. That is, when performing manual adjustment, it is possible to proceed with the adjustment while checking the updated adjustment information. Therefore, the adjustment work can be performed more easily.

[0060] According to this embodiment, the following effects can be obtained. The deposition position of the ink ejected by each recording head H on the recording medium P can be easily adjusted. More specifically, the distance between the reference portion R1 and the multiple recording heads H, i.e., the height of the recording head H, is measured by the distance sensor S. This eliminates the need to measure the height using a gap gauge or the like. In addition, the deposition position of the ink on the recording medium P is adjusted by a predetermined process performed by the control unit 118. Therefore, even if there is variation in the height of the multiple recording heads H, the deposition position can be easily adjusted. Therefore, it is possible to provide a recording device 1 that easily adjusts the deposition position of the ink.

[0061] 2. Second embodiment In the recording device according to this embodiment, the arrangement of the reference portion R1 is changed from that of the recording device 1 of the first embodiment. In the following description, the same components as those in the first embodiment are denoted by the same reference symbols, and duplicated descriptions will be omitted.

[0062] 6, in the recording device of this embodiment, the reference portion R2 is provided on the platen 3A. As described above, the platen 3A is located inside the scanning range scanned by the carriage 11 during recording. In other words, the reference portion R2 is provided at a position facing each of the recording heads H1, ..., H8, which are the recording heads H, when the carriage 11 scans within the scanning range during recording. The reference portion R2 is a generally rectangular shape that is elongated in the direction along the Y axis when viewed in a plan view from above.

[0063] In this embodiment, similarly to the first embodiment, the measurement sensor S is provided either on each recording head H or on the reference portion R2.

[0064] According to this embodiment, it is possible to obtain the same effects as those of the first embodiment.

[0065] 3. Third embodiment In the recording device according to this embodiment, the arrangement and form of the reference portion R2 are changed from the recording device according to the second embodiment. In the following description, the same components as those in the first embodiment are denoted by the same reference symbols, and duplicated descriptions are omitted.

[0066] 7, in the recording device of this embodiment, reference portions R31 to R38 are provided on a platen 3A. The reference portions R31 to R38 are not integral as in the above embodiment, but are divided and provided in accordance with the arrangement of each recording head H. Each of the reference portions R31 to R38 is substantially rectangular in a plan view from above, and has an area sufficient to overlap with each recording head H.

[0067] The reference portions R31 to R38 simultaneously face the multiple recording heads H1, ..., H8 when the carriage 11 is scanned during recording. Specifically, the recording head H1 and the reference portion R31, the recording head H2 and the reference portion R32, the recording head H3 and the reference portion R33, the recording head H4 and the reference portion R34, the recording head H5 and the reference portion R35, the recording head H6 and the reference portion R36, the recording head H7 and the reference portion R37, and the recording head H8 and the reference portion R38 each simultaneously face each other.

[0068] This makes it possible to simultaneously measure the distances between the multiple recording heads H and the corresponding reference portions R31 to R38, that is, the heights of the recording heads H. Therefore, the height measurements can be performed in a short time.

[0069] Furthermore, the arrangement of the reference portions R31-R38 is not limited to all of them facing multiple recording heads H at the same time. For example, if there is a slight swell or tilt in the X direction of the platen 3A, the reference portions R31-R38 may be provided in any area where the influence of the swell or tilt is reduced. This can improve the quality of images recorded by the recording device. [Explanation of symbols]

[0070] 1...recording device, 11...carriage, 118...control unit, H, H1, H2, H3, H4, H5, H6, H7, H8...recording head, P...recording medium, R1, R2, R31, R32, R33, R34, R35, R36, R37, R38...reference unit, S, S1, S2, S3, S4, S5, S6, S7, S8, S11, S12, S13, S14, S15, S16...distance sensors as measurement units.

Claims

1. A plurality of recording heads for ejecting liquid onto a recording medium to perform recording; a carriage carrying a plurality of the recording heads; a reference portion provided at a position capable of facing the plurality of recording heads; a measuring unit provided on either one of the plurality of recording heads or the reference unit, the measuring unit measuring a distance between the plurality of recording heads and the reference unit; a control unit that controls execution of a predetermined process based on the measurement results of the measurement unit, and adjusts the deposition positions of the liquid ejected by each of the recording heads.

2. The recording apparatus according to claim 1 , wherein the control unit stores information on the distance that has been adjusted in advance, and executes the predetermined process based on the measurement result and the information on the distance.

3. 3. The recording apparatus according to claim 1, wherein the predetermined process corrects at least one of a discharge timing and a discharge speed of the liquid.

4. each of the recording heads has an adjustment portion that adjusts the distance with respect to the reference portion; The recording apparatus according to claim 1 , wherein the predetermined process controls the adjustment unit to automatically adjust the distance.

5. each of the recording heads has an adjustment portion that adjusts the distance with respect to the reference portion; The recording apparatus according to claim 3 , wherein the predetermined process includes a process of correcting at least one of a discharge timing and a discharge speed of the liquid, and a process of controlling the adjustment unit to automatically adjust the distance.

6. each of the recording heads has an adjustment portion that adjusts the distance with respect to the reference portion; The recording apparatus according to claim 1 , wherein the predetermined process notifies adjustment information for adjusting the distance by the adjustment unit.

7. The recording apparatus according to claim 6 , wherein the adjustment information is updated successively at predetermined time intervals.

8. the carriage is scanned in a direction intersecting a transport direction in which the recording medium is transported, 8. The recording apparatus according to claim 1, wherein the reference portion is provided inside a scanning range in which the carriage is scanned and at a position facing each of the recording heads when the carriage is scanned.

9. 9. The recording apparatus according to claim 8, wherein the reference portion is provided outside a transport path along which the recording medium is transported, and faces each of the recording heads in sequence as the carriage is scanned.

10. 9. The recording apparatus according to claim 8, wherein the reference portion simultaneously faces the plurality of recording heads when the carriage is scanned.

11. The recording apparatus according to claim 1 , wherein the measurement unit is provided in each of the recording heads.

12. The recording apparatus according to claim 8 , wherein the measurement unit is disposed at a center of the recording head in the transport direction.

13. The recording device described in Claim 12, wherein the measurement unit is provided in each of the recording heads.

14. The recording apparatus according to claim 1 , wherein a plurality of the measurement sections are provided on the reference section corresponding to a plurality of the recording heads.

15. The recording apparatus according to claim 1 , wherein the measurement section has an ultrasonic sensor including a thin-film piezoelectric element.

Images