Liquid dispensing device

Abstract

The challenge is to appropriately detect the displacement of the recording medium. [Solution] A liquid dispensing device 1 comprises a carriage 3 that is movable in the main scanning direction and holds a liquid dispensing head 31, a second platen 72 that supports a conveyed recording medium M, and a camera 32 provided on the carriage 3, wherein the second platen 72 has a grid pattern E on the side that supports the recording medium M, which is imaged by the camera 32, and the displacement of the recording medium M is detected by the image of the recording medium M and the grid pattern E captured by the camera 32.

Description

Technical Field

[0001] The present invention relates to a liquid ejection device.

Background Art

[0002] In a liquid ejection device that ejects liquid onto a conveyed recording medium, there is a problem that floating (displacement) from a platen (support member) occurs on the conveyed recording medium, which causes jamming of the recording medium.

[0003] On the other hand, in the printing device of Patent Document 1 (Japanese Patent Application Laid-Open No. 2016-159528), a projection pattern is projected onto a recording medium by a projection device and imaged by a plurality of cameras. Then, the distortion of the recording medium is detected based on whether moire fringes are present in the superimposed image of the imaged projection pattern and the reference pattern.

Summary of the Invention

Problems to be Solved by the Invention

[0004] In the device of Patent Document 1, although the distortion of the recording medium can be detected, there is a problem that a projection device and a plurality of imaging means are required, which increases the cost of the device. For this reason, different methods for detecting displacement such as floating of the recording medium on the support portion have been demanded.

[0005] An object of the present invention is to appropriately detect the displacement of a recording medium.

Means for Solving the Problems

[0006] To solve the above problems, the present invention provides a liquid ejection device including a carriage that is movably provided in a main scanning direction and holds a liquid ejection head, a support member that supports a conveyed recording medium, and imaging means provided on the carriage. The support member has a detection portion on a surface on the side that supports the recording medium, and the displacement of the recording medium is detected based on images of the recording medium and the detection portion imaged by the imaging means. [Effects of the Invention]

[0007] According to the present invention, the displacement of the recording medium can be appropriately detected. [Brief explanation of the drawing]

[0008] [Figure 1] This is a perspective view showing an example of the configuration of a liquid dispensing device. [Figure 2] This is a side cross-sectional view of the liquid dispensing device described above. [Figure 3] This is a perspective view showing how a camera mounted on the carriage captures images of the recording medium and the platen. [Figure 4] This figure shows an example of an image captured by a camera. [Figure 5] This is a schematic diagram illustrating an example of a method for calculating the amount of floating on a recording medium. [Figure 6] This is a flowchart illustrating the procedure for float detection and correction operations using a liquid dispensing device according to one embodiment. [Figure 7] This is a diagram showing an example of a lenticular display. [Figure 8] This figure shows a modified example of a detection unit formed on a mounting surface. [Figure 9] This is a hardware configuration diagram of a liquid dispensing device according to one embodiment. [Figure 10] This is a functional block diagram illustrating the functional configuration related to float detection and correction operations of a liquid dispensing device according to one embodiment. [Modes for carrying out the invention]

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings. In each figure, the same or corresponding parts are denoted by the same reference numerals, and redundant explanations will be simplified or omitted as appropriate. In the following description, a liquid dispensing device that dispenses ink as a liquid will be given as an example of a liquid dispensing device according to one embodiment of the present invention.

[0010] Figure 1 shows an example of the configuration of a liquid dispensing device 1, which is an image forming apparatus. As shown in Figure 1, the liquid dispensing device 1 comprises a carriage 3, a main scanning motor 4, a sub-scanning motor 5, a support section 7, and a guide rod 8.

[0011] The carriage 3 is equipped with multiple inkjet-type liquid ejection heads 31 (see Figure 2). The liquid ejection heads are the liquid ejection means in this embodiment. Each liquid ejection head ejects ink of a predetermined color. The liquid ejection heads are mounted on the carriage 3 with their ejection surfaces facing downwards.

[0012] The carriage 3 is supported by a guide rod 8 that extends along the main scanning direction X. The carriage 3 reciprocates along the guide rod 8 in the main scanning direction X when driven by the main scanning motor 4.

[0013] The recording medium M is a long, printable object of varying sizes, materials, and thicknesses, such as paper or vinyl chloride.

[0014] A feed roll 41, which serves as a feed member, is provided behind the liquid discharge device 1 in the sub-scanning direction Y, and a winding roll 61, which serves as a winding member, is provided in front of the liquid discharge device 1 in the sub-scanning direction Y.

[0015] The recording medium M is pulled out from its wound state on the feed roll 41 and set on the platen of the support unit 7. After a predetermined image is printed on the platen, it is wound onto the take-up roll 61. In other words, the recording medium M is pulled out from the feed roll 41 by the driving force of the sub-scanning motor 5, transported intermittently, and wound onto the take-up roll 61.

[0016] When the sub-scanning motor 5 is driven and the recording medium M is conveyed to a predetermined position, the conveyance of the recording medium M is temporarily stopped. During that time, the main-scanning motor 4 is driven, and the carriage 3 reciprocates in the main-scanning direction X along the guide rod 8 while discharging ink onto the recording medium M. As a result, an image such as characters, figures, pictures, photos, etc. is formed on the recording medium M.

[0017] In this way, the liquid ejection device 1 is configured as, for example, an inkjet printer having an inkjet-type liquid ejection head. Also, the liquid ejection device 1 is, for example, a serial printer that moves the carriage 3 to perform printing. The liquid ejection device 1 may be configured as a wide-format machine in which the moving distance of the carriage 3 in the main-scanning direction X is long.

[0018] As shown in FIG. 2, the conveyance mechanism of the liquid ejection device 1 includes a feeding unit 40, a conveyance unit 50, and a winding unit 60. The feeding unit 40 is disposed behind the liquid ejection device 1. The winding unit 60 is disposed in front of the liquid ejection device 1. The conveyance unit 50 is disposed at a position upstream of the liquid ejection position C, which is a position facing the carriage 3 in the conveyance direction B of the recording medium M.

[0019] The conveyance direction B of the recording medium M is the direction along the surface of the recording medium M from the position where the recording medium M is pulled out from the feeding roll 41 to the position where it is wound around the winding roll 61. Hereinafter, the conveyance direction B of the recording medium M is simply referred to as the conveyance direction, and the upstream side or the downstream side in the conveyance direction is simply referred to as the upstream side or the downstream side. Also, the surface of the recording medium M on which liquid is ejected (the upper surface in FIG. 2) is referred to as the ejection surface, and the opposite surface is referred to as the back surface.

[0020] The support unit 7 includes a first platen 71, a second platen 72 as a support member, and a third platen 73. These platens extend in the sub-scanning direction which is perpendicular to the plane of FIG. 2, and support the recording medium M from its back side over the sub-scanning direction. The first platen 71 is provided upstream of the liquid discharge position C in the recording medium conveyance direction B. The second platen 72 is provided facing the liquid discharge position C and supports the recording medium M when liquid is discharged. The third platen 73 is provided downstream of the liquid discharge position C at a position facing the curing heater 23. These platens are made of, for example, plate-like members and are configured by connecting them in the conveyance direction.

[0021] One end of the first platen 71 is formed in a cross-sectional arc shape that extends so as to drop toward the feeding unit 40. The second platen 72 extends along the sub-scanning direction. One end of the third platen 73 is formed in a cross-sectional arc shape that extends so as to drop toward the take-up unit 60.

[0022] Also, small suction grooves 72a are provided in the second platen 72 at least in the printing area directly under the carriage 3, and the recording medium M is configured to be adsorbed onto the platen 7 by a fan. Thereby, the lifting of the recording medium M from the platen 7 is suppressed, and the recording medium M can be conveyed along the platen 7.

[0023] The liquid discharge device​​​​​​​The recording medium M is wound around the delivery roll 41. The delivery motor 43 is the drive source that generates tension on the delivery unit 40 side. The tension applied to the recording medium M is adjusted by the torque limiter 46.

[0026] The encoder sheet 44r is mounted on the rotation axis of the feed roll 41 and detects the amount of rotation of the feed roll 41. The encoder sensor 45r detects the remaining amount of recording medium M based on the amount of rotation of the feed roll 41 detected by the encoder sheet 44r.

[0027] The encoder sheet 44m is mounted on the rotation axis of the delivery motor 43 and detects the amount of rotation of the delivery motor 43. The encoder sensor 45m detects the rotation speed of the delivery motor 43 based on the amount of rotation of the delivery motor 43 detected by the encoder sheet 44m.

[0028] When the delivery motor 43 is rotated and force is applied in the opposite direction to the sub-scanning direction Y, which is the transport direction of the recording medium M, tension is applied to the recording medium M held by the transport rollers 51 and pressure rollers 52 of the transport unit 50, causing the torque limiter 46 of the delivery unit 40 to slip.

[0029] As a result, the torque limiter 46 creates a feed tension that feeds out the recording medium M, and this tension is applied to the recording medium M. Therefore, as the feed roll 41 rotates, the recording medium M is fed onto the platen 7. This also ensures that the tension between the feed unit 40 and the transport unit 50 remains constant.

[0030] The transport unit 50 includes a transport roller 51, a pressure roller 52, a sub-scanning motor 5, an encoder sheet 54r, and an encoder sensor 55r.

[0031] The sub-scanning motor 5, acting as a transport motor, is the drive source for rotating the transport roller 51. The pressure roller 52 applies pressure to the transport roller 51 in order to transmit the power of the transport roller 51 to the recording medium M.

[0032] The encoder sheet 54r is mounted on the rotation axis of the transport roller 51 and detects the amount of rotation of the transport roller 51. The encoder sensor 55r detects the rotation speed of the transport roller 51 based on the amount of rotation of the transport roller 51 detected by the encoder sheet 54r.

[0033] The transport roller 51 rotates as the sub-scanning motor 5 is rotated while the recording medium M is sandwiched between the transport roller 51 and the pressure roller 52. As a result, the recording medium M is transported in the sub-scanning direction Y. The sub-scanning motor 5 can rotate the transport roller 51 in both forward and reverse directions, allowing the recording medium M to be transported in the transport direction and the opposite direction.

[0034] The delivery unit 40 and the transport unit 50 are driven intermittently. As a result, while the carriage 3 reciprocates in the main scanning direction X by the main scanning motor 4 described above, the recording medium M moves intermittently on the platen 7.

[0035] The winding unit 60 includes a winding roll 61, a winding motor 63, encoder sheets 64r and 64m, encoder sensors 65r and 65m, and a torque limiter 66.

[0036] The recording medium M, which has been printed and collected, is wound onto the winding roll 61. The winding motor 63 is the drive source that generates tension on the winding unit 60 side. The tension applied to the recording medium M is adjusted by the torque limiter 66.

[0037] The encoder sheet 64r is mounted on the rotation axis of the winding roll 61 and detects the amount of rotation of the winding roll 61. The encoder sensor 65r detects the amount of winding of the recording medium M based on the amount of rotation of the winding roll 61 detected by the encoder sheet 64r.

[0038] The encoder sheet 64m is mounted on the rotation axis of the winding motor 63 and detects the amount of rotation of the winding motor 63. The encoder sensor 65m detects the rotation speed of the winding motor 63 based on the amount of rotation of the winding motor 63 detected by the encoder sheet 64m.

[0039] When the winding motor 63 is rotated, the torque limiter 66 slips, creating winding tension that winds the recording medium M, and this tension is applied to the recording medium M. As a result, the winding roll 61 rotates, and the recording medium M is wound up by the winding roll 61.

[0040] As described above, the liquid dispensing device 1 is also configured as a transport device for transporting the recording medium M by a transport mechanism comprising a dispensing unit 40, a transport unit 50, and a winding unit 60.

[0041] In the liquid dispensing device 1 of this embodiment, the floating (displacement) of the recording medium M from the second platen 72 is detected before the liquid is dispensed onto the recording medium M by the liquid dispensing head 31. The floating detection of the recording medium M will be explained below using the perspective view in Figure 3. For convenience, the recording medium M is shown as a dotted line in Figure 3, but in reality it is placed on the second platen 72 and its surface is covered.

[0042] As shown in Figure 3, a camera 32 is mounted on the carriage 3 as an imaging means. The camera 32 is positioned to be able to move up and down as indicated by the double arrow C while held by the carriage 3, and to change its orientation in the sub-scanning direction Y as indicated by the double arrow D, thereby allowing its imaging range to be varied. The imaging means of this embodiment generates a two-dimensional image by irradiating the object to be imaged with light from a light source provided inside it and receiving the reflected light reflected from the object to be imaged.

[0043] The second platen 72 has a grid pattern E formed on its mounting surface 72b on which the recording medium M is placed, which serves as a detection unit. The grid pattern E is a repeating shape in which a grid shape that is convex towards the recording medium M side or concave relative to the recording medium M is repeated along the entire mounting surface 72b, that is, along the main scanning direction X and sub-scanning direction Y of the mounting surface 72b, compared to the rest of the mounting surface 72b. The mounting surface 72b is the side of the second platen 72 that supports the recording medium M.

[0044] Camera 32 images the recording medium M on the mounting surface 72b and the mounting surface 72b, including the boundary between them. In other words, camera 32 images the side edge portion of the recording medium M and its surrounding portion. As a result, the grid pattern E in the region outside the recording medium M is also imaged simultaneously. During this imaging operation, the carriage 3 is positioned on one side (the right side in Figure 3) outside the region through which the recording medium M passes in the main scanning direction X. This prevents the recording medium M from coming into contact with the carriage 3 due to lifting during the imaging operation. Therefore, damage to the carriage 3 and contamination of the recording medium M can be prevented.

[0045] Figure 4 shows an example of an image captured by camera 32, and Figure 5 is a schematic diagram showing how the amount of floating on the recording medium M is calculated.

[0046] As shown in Figure 4, the camera 32 images the side edge Ma, which is at least one side (right side in Figure 3) of the recording medium M in the main scanning direction, and the peripheral area of ​​the side edge Ma of the mounting surface 72b of the second platen. As can be seen from the image in Figure 4, a grid pattern E is formed on the mounting surface 72b, allowing the region of the mounting surface 72b and the region of the recording medium M to be distinguished in the image by the presence or absence of the grid pattern E. In other words, the position where the grid pattern E is interrupted can be recognized as the side edge Ma of the recording medium M. In Figure 4, due to the lifting of the recording medium M from the mounting surface 72b, the side edge Ma changes from a state where the recording medium M is in close contact with the mounting surface 72b and the side edge Ma is straight (see dotted line in Figure 4) to a wavy state.

[0047] Figure 5 is a schematic diagram illustrating an example of a method for calculating the amount of floating of the recording medium M, and is a cross-sectional view perpendicular to the transport direction of the recording medium M. As shown in Figure 5, suppose a camera captures an image of the plane G-G' from point O. In this case, we calculate the amount of floating J of the recording medium M. The amount of floating J is the distance from the side edge position H1 of the recording medium M to point H2 on the mounting surface 72b of the platen directly below it. On the image captured by the camera, points H1 and H2 are projected onto points H1' and H2', respectively. The angle α, which is the imaging angle from point O to the mounting surface 72b, is a known value. Using these points H1', ​​H2', and angle α, the positions of points H1 and H2 can be calculated, and the amount of floating J can be calculated.

[0048] As described above, according to this embodiment, by providing a grid pattern (detection unit) on the surface of the second platen (support member), it becomes possible to detect the floating (displacement relative to the support member) of the recording medium from the support member or to calculate the amount of floating (calculation of displacement). Therefore, the floating of the recording medium can be appropriately corrected by subsequent correction operations and brought into close contact with the second platen. Furthermore, since the imaging means is provided only on the carriage and no other members are required, floating of the recording medium can be detected with a simple configuration. The amount of floating of the recording medium is the amount of floating from the state in which the recording medium is in close contact with the support member, or the distance from the support surface of the recording medium to the floating part of the recording medium (distance in the direction perpendicular to the main scanning direction and sub-scanning direction).

[0049] Figure 6 is a flowchart showing the procedure for float detection and correction operations in the liquid dispensing device of this embodiment. As shown in Figure 6, when a print job is started in the liquid ejection device, the aforementioned imaging operation is performed by the camera 32 (step S1). Based on the captured image, the image processing unit performs image processing on the captured image (S2). This image processing includes multiplexing of the continuously captured images, and, if buoyancy detection is performed using images for each wavelength, decomposition into RGB monochrome images.

[0050] Next, the floating amount calculation unit of the liquid dispensing device calculates the floating amount of the recording medium M from the image and determines whether the floating amount is within a reference value (S3, S4). If it is within the reference value, the floating detection operation ends, the recording medium is transported, and the liquid dispensing operation begins.

[0051] On the other hand, if the amount of floating exceeds a reference value, a floating correction operation is performed (S5). The floating correction operation is performed by feeding and returning the recording medium M. Specifically, the sub-scanning motor 5 (see Figure 2) rotates the transport roller 51 in the forward and reverse directions to transport the recording medium M in the direction of arrow B, which is the winding direction by the winding roll 61 (feed operation), and then transports it in the opposite direction (return operation). This applies tension to the recording medium M and corrects the floating of the recording medium M. The amount of transport of the recording medium M in the floating correction operation is increased as the amount of floating increases. This allows the floating of the recording medium M to be corrected with an appropriate amount of movement, and the correction time can be minimized. Note that if it is not a problem for the position in the transport direction in which the image is formed on the recording medium M to change, the floating correction operation may be performed with only the feed operation.

[0052] After the float correction operation, the float detection operation is performed again (S1-S4), and this is repeated until the amount of float is within the reference position. However, the number of detection operations may be set to be performed only twice. Through the above float detection and correction operations, the liquid discharge operation can be started with the float of the recording medium M corrected, and collision between the carriage 3 and the recording medium M during the liquid discharge operation can be prevented. Therefore, damage to the carriage 3 and contamination of the recording medium M can be prevented.

[0053] The series of float detection operations may be performed at the start of the print job, or when the liquid ejector is started.

[0054] Alternatively, the camera 32's orientation can be changed to calculate the amount of buoyancy from images taken from multiple directions. This enables three-dimensional measurement and allows for the calculation of buoyancy from multiple directions, thereby improving the accuracy of buoyancy detection.

[0055] Furthermore, the detection unit formed on the mounting surface 72b can be a lenticular display body including a lenticular lens and a lenticular image. For example, as shown in Figure 7, the lenticular image 76 of the lenticular display body 79 is provided between the mounting surface 72b and the lenticular lens 74. The lenticular lens 74 has a plurality of convex lenses 75 on the mounting surface 72b side. The lenticular image 76 has a plurality of different images 77A, 77B arranged in parallel in the parallel direction of the lenses 74. The visible image changes as the viewing angle of the lenticular display body 79 changes. In the example in Figure 7, image 77B is visible in the field of view G1, and image 77A is visible in the field of view G2. Therefore, by changing the orientation of the camera 32, it becomes possible to display different images, and since the floating of the recording medium M can be detected by multiple different images, the detection accuracy can be improved.

[0056] The grid pattern E may form suction grooves for adsorbing the recording medium M. That is, the grid pattern E may be concave, with those parts serving as suction grooves, or conversely, the grid pattern E may be convex, with the parts in between serving as suction grooves. This eliminates the need to provide separate suction grooves on the mounting surface 72b, thereby reducing constraints on the arrangement of the grid pattern E and simplifying the configuration of the second platen 72 (support member).

[0057] In the embodiments described above, the case in which the amount of floating is calculated by comparing the edge Ma of the recording medium M with the grid pattern E, as shown in Figure 4, was explained, but the present invention is not limited to this. That is, the recording medium M may be semi-transparent, for example, so that the recording medium M is transmitted and the mounting surface 72b of the second platen 72 below it is imaged. In this case, in the imaged image, in areas where the recording medium M is distorted, such as when it is floating, the grid pattern E formed on the mounting surface 72b below is also refracted and imaged due to the refraction of light. The amount of floating of the recording medium M may be calculated by analyzing the distortion of this grid pattern E. This embodiment has the advantage that, unlike the embodiments described above, the amount of floating can be calculated even in areas other than the edge on one side of the main scanning direction of the recording medium M. Therefore, it is possible to detect with higher accuracy whether or not the recording medium M is floating.

[0058] Furthermore, in this embodiment, the grid pattern E (detection unit) formed on the support member may be configured to have multiple parts with different reflectivity for each wavelength of light, for example, by being formed from multiple colors or multiple materials. This makes it possible to obtain multiple images that look different for each observation wavelength. By detecting the floating of the recording medium M using these images, the detection accuracy can be improved. For example, as shown in Figure 8, the grid pattern E has a first part E1 and a second part E2 with different light reflectivity. Specifically in Figure 8, the first part E1 and the second part E2 are arranged alternately in each line segment forming the grid pattern E. When the image captured by the camera 32 is decomposed into image data of a specific first wavelength, only the first part E1 is displayed, and when it is decomposed into image data of a second wavelength different from the first wavelength, only the second part E2 is displayed. Note that even in the case of a non-transparent recording medium M, a detection unit having multiple parts with different light reflectivity, as shown in Figure 8, may be provided. Also, the detection unit may have three or more parts with different light reflectivity.

[0059] Thus, the detection portion provided on the support member may be formed as a convex or concave shape relative to the rest of the mounting surface 72b, or it may be formed as a portion with a different light reflectivity from the surface of the recording medium M, such as by being colored differently or made of a different material from the recording medium M or the rest of the mounting surface 72b. In other words, the detection portion only needs to be a portion that can be distinguished from the surface of the recording medium M in the image captured by the imaging means.

[0060] Furthermore, the detection section formed on the mounting surface 72b of the second platen 72 (support member) on which the recording medium M is placed is not limited to a repeating grid shape as in this embodiment, but may have an irregular shape formed across the entire mounting surface 72b. Also, in this embodiment, the detection section only needs to be provided at least at positions corresponding to the positions of the ends in the main scanning direction of recording media of each size or any of the sizes to which the liquid discharge device is connected, and around them, and does not need to be provided across the entire mounting surface 72b. In this way, the range and position of the grid pattern E (detection section) formed on the second platen 72 (support member) can be changed as needed. For example, in the case of a transmissive recording medium M, the detection section may be provided over the entire recording medium passage area in the main scanning direction, or only in a part thereof.

[0061] The displacement of the recording medium detected by the image captured by the imaging means is not limited to the floating of the recording medium from the support member as in this embodiment (i.e., a state in which a part of the recording medium is displaced from the support member in the thickness direction of the recording medium), but may also be, for example, a positional misalignment (displacement) of the entire recording medium on the support member in the main scanning direction. In this case, a reference portion that serves as a reference position in the main scanning direction may be provided on the support member at a position corresponding to the position of the main scanning edge of the recording medium that is not misaligned, and this can be read by the imaging means. For example, the positional misalignment of the recording medium in the main scanning direction can be detected by comparing the reference portion of the captured image with the position of the side edge of the recording medium.

[0062] Furthermore, the camera 32 in this embodiment may be used not only to detect the displacement of the recording medium, but also to detect the feed amount of the carriage 3 in the main scanning direction and the feed amount of the recording medium M in the transport direction, and to detect image leakage (loss of liquid ejection operation by a specific nozzle) when forming an image on the recording medium M.

[0063] The recording medium that the liquid dispensing device transports and forms images on is not limited to a continuous sheet of recording medium that is fed out from a feeding member and wound up by a winding member, as in this embodiment, but may also be individual recording media. Furthermore, appropriate means can be used to correct the floating of the recording medium from the support member. For example, the floating may be corrected by pressing the surface of the recording medium on the support member with a pressing means.

[0064] Next, the hardware configuration of the liquid dispensing device will be described with reference to Figure 9. Figure 9 is a hardware configuration diagram of a liquid dispensing device according to one embodiment. The liquid dispensing device 1 includes a CPU 301 (Central Processing Unit) 301, a ROM (ReadOnly Memory) 302, and a RAM (Random Access Memory) 303. The liquid dispensing device 1 also includes an NVRAM (Non-Volatile Random Access Memory) 304.

[0065] The liquid dispensing device 1 also includes an external device connection interface 308, a network interface 309, and a bus line 310. Furthermore, the liquid dispensing device 1 includes a transport device 311, a transport driver 312, and an operation panel 330. The carriage 3 includes a liquid dispensing head driver 322 and a plurality of liquid dispensing heads 31 for dispensing liquids of various colors.

[0066] The CPU 301 controls the overall operation of the liquid dispensing device 1. The ROM 302 stores programs used to drive the CPU 301, such as IPL. The RAM 303 is used as the work area for the CPU 301. The NVRAM 304 stores various data, such as programs, and preserves this data even when the power to the liquid dispensing device 1 is cut off.

[0067] The external device connection interface 308 is connected to a PC (Personal Computer) via a USB (Universal Serial Bus) cable, etc., and communicates control signals and print data with the PC. The network interface 309 is an interface for data communication using a communication network such as the Internet. Bus line 310 is an address bus and data bus, etc., for electrically connecting each component such as the CPU 301.

[0068] The transport device 311, for example, consists of rollers and a motor that drives the rollers, and transports the recording medium M in the transport direction along the transport path within the liquid discharge device 1. The transport driver 312 controls the movement of the transport device 311 in the transport direction.

[0069] The liquid ejection head 31 forms an image on the recording medium M by ejecting liquid to a predetermined position on the recording medium M, which is intermittently transported in the transport direction. The liquid ejection head driver 322 is a drive circuit that controls the driving of the liquid ejection head 31.

[0070] The control panel 330 consists of a touch panel that displays the current settings or selection screen, accepts input from the operator, and an alarm lamp, etc.

[0071] The liquid discharge head driver 322 may not be mounted on the carriage 3, but rather located outside the carriage 3 and connected to the bus line. Furthermore, the transport driver 312 and the liquid discharge head driver 322 may be configured with functions implemented by instructions from the CPU 301 according to a program.

[0072] Figure 10 is a functional block diagram illustrating the functional configuration related to the float detection and correction operation of the liquid dispensing device in this embodiment. As shown in Figure 10, the liquid dispensing device 1 includes a recording medium detection means 351, an image processing unit 352, a float amount calculation unit 353, and a drive control unit 354. These functional parts are realized, for example, by a program that causes a processor such as a CPU 301 (see Figure 9) to execute various functions.

[0073] When the recording medium detection means 351 detects that the recording medium has been transported to a predetermined position, the camera 32 performs an imaging operation. The camera 32 sends the captured image to the image processing unit 352, which performs the aforementioned image processing. The processed image is sent to the float amount calculation unit 353, where the float amount of the recording medium M is calculated. Based on this float amount, the drive control unit 354 controls the transport driver 312 to perform the feeding and returning operations of the recording medium M. The drive control unit 354 can also change the position and orientation of the camera 32 relative to the carriage and change the imaging range of the camera 32.

[0074] Although embodiments of the present invention have been described above, the present invention is not limited to the embodiments described above, and various modifications can be made without departing from the spirit of the present invention.

[0075] In this application, the discharged liquid is not particularly limited as long as it has a viscosity and surface tension that can be discharged from the head, but it is preferable that its viscosity becomes 30 mPa·s or less at room temperature and atmospheric pressure, or when heated or cooled. More specifically, it is a solution, suspension, emulsion, etc. containing a solvent such as water or an organic solvent, a colorant such as a dye or pigment, a polymerizable compound, a resin, a functional material such as a surfactant, a biocompatible material such as DNA, amino acids or proteins, calcium, or an edible material such as a natural pigment. These can be used, for example, as inkjet inks, surface treatment liquids, liquids for forming components of electronic elements and light-emitting elements or electronic circuit resist patterns, and three-dimensional molding material liquids.

[0076] The term "liquid" includes not only ink but also paints, pre-treatment solutions, binders, and overcoat solutions.

[0077] In this application, a "liquid dispensing device" is a device that includes a carriage having a liquid dispensing head and drives the liquid dispensing head to dispense liquid. A liquid dispensing device includes not only devices that can dispense liquid onto a recording medium to which liquid can adhere, but also devices that dispense liquid into air or into liquid.

[0078] This "liquid dispensing device" may also include means for feeding, transporting, and dispensing paper onto materials to which liquid can adhere, as well as pre-treatment devices, post-treatment devices, etc.

[0079] For example, "liquid ejection devices" include image forming devices that eject ink to form images on paper, and three-dimensional molding devices that eject molding liquid into a powder layer formed in layers to create three-dimensional objects.

[0080] Furthermore, the term "liquid dispensing device" is not limited to those that visualize meaningful images such as letters or figures through the dispensed liquid. For example, it also includes devices that form patterns that do not have meaning in themselves, or devices that create three-dimensional images.

[0081] The term "material to which liquid can adhere" above refers to a material to which liquid can adhere at least temporarily, such as material to which liquid adheres and solidifies, or material to which liquid adheres and penetrates, and is the recording medium in the above embodiment. Specific examples include recording media such as paper, recording paper, film, and cloth; electronic components such as electronic circuit boards and piezoelectric elements; powder layers; organ models; and inspection cells. Unless otherwise specified, it includes all materials to which liquid can adhere.

[0082] The materials referred to as "materials to which liquid can adhere" above include paper, thread, fibers, fabrics, leather, metal, plastic, glass, wood, ceramics, etc., as long as liquid can adhere to them, even temporarily.

[0083] Other types of "liquid dispensing devices" include processing liquid coating devices that dispense processing liquid onto the surface of paper for purposes such as modifying the paper surface, and injection granulation devices that granulate fine particles of raw materials by spraying a compositional liquid, in which raw materials are dispersed in a solution, through a nozzle.

[0084] In this application, the terms image formation, recording, printing, copying, printing, and shaping are all considered synonymous.

[0085] Examples of the present invention are as follows: <1> A carriage is provided to be movable in the main scanning direction and holds the liquid discharge head, A support member that supports the recording medium being transported, A liquid dispensing device comprising an imaging means provided on the carriage, The support member has a detection unit on the side that supports the recording medium, which is imaged by the imaging means. This liquid dispensing device is characterized by detecting the displacement of the recording medium using images of the recording medium and the detection unit captured by the imaging means. <2> The detection unit includes a convex or concave portion relative to the surface of the support member. <1> This is the liquid dispensing device described. <3> The detection unit forms an adsorption groove for adsorbing the recording medium. <2> This is the liquid dispensing device described. <4> The detection unit includes a portion of the recording medium whose surface has a different reflectance for each wavelength of light. <1> This is the liquid dispensing device described. <5> The imaging means changes its imaging range by changing its orientation relative to the carriage. <1> from <4> It is a liquid dispensing device as described in one of the following terms. <6> The detection unit includes a lenticular lens with convex lenses arranged in parallel, and a lenticular image with multiple images arranged in parallel, provided between the lenticular lens and the support member, and is a lenticular display body in which the image visible differs depending on the observation angle. <1> from <5> It is a liquid dispensing device as described in one of the following terms. <7> The imaging means detects the floating of the recording medium from the support member based on the images of the recording medium and the detection unit captured by the imaging means. The recording medium is a continuous record medium that is fed out from a feeding member and wound up by a winding member. By transporting the recording medium in the winding direction or the reverse direction, the lifting of the recording medium from the support member is corrected. The imaging means calculates the amount of lift of the recording medium relative to the support member based on the image it captures, and changes the amount of transport of the recording medium in the winding direction or the reverse direction based on the calculated amount of lift. <1> from <6> It is a liquid dispensing device as described in one of the following terms. <8> The imaging means captures the detection unit by passing through the recording medium. <1> from <7> It is a liquid dispensing device as described in one of the following terms. <9> The detection unit has at least a first part and a second part having different light reflectances, and the first part of the second part is displayed by image data of a first wavelength of the image captured by the imaging means, and the second part of the second part is displayed by image data of a second wavelength having a different wavelength from the first wavelength. <1> from <8> It is a liquid dispensing device as described in one of the following terms. <10> With the carriage positioned outside the area in which the recording medium is transported in the main scanning direction, the imaging means images the recording medium and the support member. <1> from <9> It is a liquid dispensing device as described in one of the following terms. [Explanation of symbols]

[0086] 1 Liquid discharge device 3 carriages 31 Liquid dispensing head 32. Camera (imaging means) 41. Feed Roll (Feeding Member) 61. Winding roll (winding component) 72. Second platen (support member) 72b Mounting surface (the side that supports the recording medium) 74 Lenticular lenses 76 Lenticular Images 79 Lenticular display B. Direction of transport of recording medium E Grid pattern (detection unit) M recording medium X Main scanning direction Y sub-scanning direction [Prior art documents] [Patent Documents]

[0087] [Patent Document 1] Japanese Patent Publication No. 2016-159528

Claims

1. A carriage is provided to be movable in the main scanning direction and holds the liquid discharge head, A support member that supports the recording medium being transported, A liquid dispensing device comprising an imaging means provided on the carriage, The support member has a detection unit on the side that supports the recording medium, which is imaged by the imaging means. A liquid dispensing device characterized by detecting the displacement of the recording medium based on images of the recording medium and the detection unit captured by the imaging means.

2. The liquid dispensing device according to claim 1, wherein the detection unit includes a convex or concave portion relative to the surface of the support member.

3. The liquid dispensing device according to claim 2, wherein the detection unit forms an adsorption groove for adsorbing the recording medium.

4. The liquid dispensing apparatus according to claim 1, wherein the detection unit includes a portion of the recording medium that has a different reflectance for each wavelength of light from the surface of the recording medium.

5. The liquid dispensing device according to claim 1, wherein the imaging means changes its orientation relative to the carriage to change its imaging range.

6. The liquid dispensing device according to claim 1, wherein the detection unit includes a lenticular lens in which convex lenses are arranged in parallel, and a lenticular image in which a plurality of images are arranged in parallel, provided between the lenticular lens and the support member, wherein the image visible differs depending on the observation angle.

7. The imaging means detects the floating of the recording medium from the support member based on the images of the recording medium and the detection unit captured by the imaging means. The recording medium is a continuous record medium that is fed out from a feeding member and wound up by a winding member. By transporting the recording medium in the winding direction or the reverse direction, the lifting of the recording medium from the support member is corrected. The liquid dispensing device according to claim 1, which calculates the amount of floating of the recording medium relative to the support member based on the image captured by the imaging means, and changes the amount of transport of the recording medium in the winding direction or the reverse direction based on the calculated amount of floating.

8. The liquid dispensing apparatus according to claim 1, wherein the imaging means images the detection unit by passing through the recording medium.

9. The liquid dispensing apparatus according to claim 8, wherein the detection unit has at least a first part and a second part having different light reflectances, the first part of the first part and the second part is displayed by image data of a first wavelength of the image captured by the imaging means, and the second part of the first part and the second part is displayed by image data of a second wavelength having a different wavelength from the first wavelength.

10. The liquid dispensing apparatus according to claim 1, wherein the imaging means images the recording medium and the support member while the carriage is positioned outside the area in which the recording medium is transported in the main scanning direction.

Images