Printer

Abstract

To provide a printer capable of securely detecting a state of a light irradiation device with less optical sensors.SOLUTION: A printer 10 includes: an ink head 41 discharging photocuring ink; a light irradiation device 50 irradiating light for curing ink; a measuring box 160 having an opening 164 and an interior space S1; and an optical sensor 170 having a light receiving part 171 disposed so as to face the interior space S1 of the measuring box 160. The optical sensor 170 measures the strength of light received by the light receiving part 171. The measuring box 160 further includes a reflection part 165 disposed in the interior space S1 and reflecting light incident from the opening 164. The light receiving part 171 receives light incident from the opening 164 and reflected in the reflection part 165.SELECTED DRAWING: Figure 3

Description

[Technical field]

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

[0002] Inkjet printers equipped with an inkjet head that ejects photocurable ink that hardens when exposed to light of a specific wavelength range onto a recording medium, and a light irradiation device that irradiates light to harden the photocurable ink, have been known for some time. In an inkjet printer that uses photocurable ink, it is preferable to check the intensity of light irradiated from the light irradiation device periodically or as needed in order to stably harden the ink. For example, Patent Document 1 discloses an inkjet printer equipped with a plurality of light sources arranged in an array, an illuminance sensor that measures the illuminance of each of the plurality of light sources, and a light shielding wall that prevents the illuminance sensor from being irradiated with light from light sources that are not the object of measurement. According to Patent Document 1, such a configuration makes it possible to accurately identify light sources with reduced illuminance.

[0003] Even when multiple light sources are not used, for example, the intensity of light emitted by the light irradiation device may be partially reduced due to dirt on the light irradiation device. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] JP 2015-89633 A Summary of the Invention [Problem to be solved by the invention]

[0005] As described in Patent Document 1, it is considered possible to detect a partial decrease in the intensity of light irradiated by a light irradiation device by measuring the intensity of light irradiated by multiple parts of the light irradiation device. However, in reality, the number of optical sensors that can be provided to detect the intensity of light is limited due to space, cost, and the like. If the number of optical sensors is small, it is difficult to reliably detect the state of the light irradiation device. Typically, if the number of optical sensors is small and there is no optical sensor that measures the amount of light in the part of the light irradiation device where the amount of light has decreased, a situation may occur in which a partial decrease in the amount of light cannot be found.

[0006] The present invention has been made in view of the above-mentioned problems, and an object of the present invention is to provide a printer that can more reliably detect the state of the light irradiation device using fewer optical sensors. [Means for solving the problem]

[0007] The printer disclosed herein includes an ink head that ejects photocurable ink, a light irradiation device that irradiates light to cure the ink, a measurement box having an opening and an internal space, and an optical sensor having a light receiving unit arranged to face the internal space of the measurement box. The optical sensor measures the intensity of the light received by the light receiving unit. The measurement box further includes a reflecting unit arranged in the internal space to reflect light incident from the opening. The light receiving unit is arranged to receive light incident from the opening and reflected by the reflecting unit.

[0008] According to the printer, the light emitted from the light irradiation device enters the measurement box through an opening provided in the measurement box, is reflected by a reflecting portion in the measurement box, and then reaches the light receiving portion of the light sensor. According to the knowledge of the inventor of the present application, the light reflected in the partitioned measurement box reaches the light receiving portion of the light sensor with the intensity of the light reflected from different locations being averaged during the reflection process. Therefore, for example, it is possible to discover that the light amount of the light irradiation device is at least partially reduced due to a reduction in the averaged light intensity measured by the light sensor. Therefore, according to the printer, the state of the light irradiation device can be detected more reliably with fewer light sensors. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a front view showing a printer according to a first embodiment. [Diagram 2] FIG. 2 is a plan view of the platen and the carriage. [Diagram 3] FIG. 2 is a partially cutaway front view of the platen and the carriage. [Figure 4] FIG. 2 is a block diagram of a printer. [Diagram 5] 10 is a flowchart showing an example of a process for diagnosing the state of a light irradiation device and measuring the amount of stray light. [Figure 6] 1 is a schematic diagram showing the distribution of irradiance on a wall portion of the measurement box on which a light receiving unit is installed. FIG. [Figure 7] FIG. 11 is a block diagram of a printer according to a modified example. [Figure 8] FIG. 11 is a partially cutaway front view of a printer according to a second embodiment. [Figure 9] FIG. 11 is a cross-sectional view showing a modified example of the internal configuration of the measurement box. [Figure 10] FIG. 11 is a cross-sectional view showing another modified example of the internal configuration of the measurement box. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] An inkjet printer according to an embodiment will be described below with reference to the drawings. It should be noted that the embodiment described here is not intended to limit the present invention. In the following description, when the inkjet printer is viewed from the front, the side away from the inkjet printer is the front, and the side approaching the inkjet printer is the rear. The symbols F, Rr, L, R, U, and D in the drawings represent the front, rear, left, right, top, and bottom, respectively. In the following description, the left-right direction of the inkjet printer is also called the main scanning direction, and the front-back direction is also called the sub-scanning direction. The symbols X, Y, and Z in the drawings represent the sub-scanning direction, main scanning direction, and up-down direction, respectively. The main scanning direction Y, the sub-scanning direction X, and the up-down direction Z are perpendicular to each other. However, these are merely directions for convenience of description, and do not limit the installation mode of the inkjet printer.

[0011] [First embodiment] 1 is a front view of a large-format inkjet printer (hereinafter, simply referred to as "printer") 10 according to one embodiment. The printer 10 prints an image on the recording medium 5 by moving a roll-shaped recording medium 5 in a sub-scanning direction X (see FIG. 2) and ejecting ink from a recording head 40 mounted on a carriage 30 that moves in a main scanning direction Y.

[0012] The recording medium 5 is an object on which an image is printed. The recording medium 5 is not particularly limited. For example, the recording medium 5 may be paper such as plain paper or inkjet printing paper, or may be a transparent sheet made of resin or glass. It may be a sheet made of metal or rubber. It may also be a fabric.

[0013] 1, the printer 10 includes a platen 20, a carriage 30, a recording head 40, a light irradiation device 50, a carriage moving device 60, a transport device 70, a capping device 80, a wiping device 90, and a control device 100. The printer 10 according to this embodiment also includes a light quantity measuring device 150 that measures the intensity of reflected light of light irradiated from the light irradiation device 50.

[0014] The platen 20 is a support platform that supports the recording medium 5. FIG. 2 is a plan view of the platen 20 and the carriage 30. As shown in FIGS. 1 and 2, the platen 20 extends in the main scanning direction Y and the sub-scanning direction X. The upper surface of the platen 20 constitutes a support surface 20a that supports the recording medium 5. The support surface 20a of the platen 20 faces upward. As shown in FIG. 2, the support surface 20a extends in the main scanning direction Y, and a printing area R1y with respect to the main scanning direction Y is set on the support surface 20a. As shown in FIG. 2, the support surface 20a also extends in the sub-scanning direction X, and a printing area R1x with respect to the sub-scanning direction X is set on the support surface 20a. Hereinafter, the printing area of ​​the printer 10 defined by the printing area R1y with respect to the main scanning direction Y and the printing area R1x with respect to the sub-scanning direction X is also referred to as the printing area R1. The printing area R1 is the maximum area in which the printer 10 can form an image. 2, the platen 20 exists not only inside the printing region R1 but also outside it. Hereinafter, the outside of the printing region R1 in a plan view will also be referred to as an outer region R2. In addition, within the outer region R2, the region on the platen 20 in a plan view will also be referred to as region R2a, and the region outside the platen 20 will also be referred to as region R2b.

[0015] 2, a light collecting hole 21 is provided in region R2a of platen 20. Light collecting hole 21 is a through-hole that passes through platen 20 in the vertical direction. Details of light collecting hole 21 will be described later.

[0016] As shown in FIG. 1, the carriage 30 is provided above the support surface 20a of the platen 20. The carriage 30 holds a recording head 40 and a light irradiation device 50. Thus, the recording head 40 and the light irradiation device 50 are also located above the support surface 20a of the platen 20. The recording head 40 and the light irradiation device 50 are provided to face the platen 20. As shown in FIG. 1, the recording head 40 is provided on the lower surface of the carriage 30. The recording head 40 includes a plurality of ink heads 41. As shown in FIG. 2, the plurality of ink heads 41 each extend in the sub-scanning direction X and are arranged side by side in the main scanning direction Y.

[0017] Each ink head 41 has a nozzle surface 41b in which a plurality of nozzles 41a for ejecting ink are formed. In each nozzle surface 41b, the plurality of nozzles 41a are aligned in the sub-scanning direction X to form a nozzle row. Although the number of nozzles in each ink head 41 shown in FIG. 2 is small, a larger number of nozzles 41a (for example, 300) are actually formed. The number of nozzles provided in the ink head 41 is not particularly limited. The number of inkjet heads provided in the recording head 40 is four here, but is not particularly limited. The arrangement of the plurality of ink heads 41 is also not limited, and for example, some of the plurality of ink heads 41 may be shifted in the sub-scanning direction X from the others.

[0018] In this embodiment, all of the inks ejected from the multiple nozzles 41a are photocurable inks. The photocurable inks are ultraviolet-curable inks that are cured when irradiated with ultraviolet rays. The components, characteristics, and the like of the photocurable inks are not particularly limited.

[0019] The light irradiation device 50 is provided on the carriage 30. Here, the light irradiation device 50 is provided to the left of the recording head 40. FIG. 3 is a partially cutaway front view of the platen 20 and the carriage 30. As shown in FIGS. 2 and 3, the light irradiation device 50 includes a light source 51, a case 52 in which the light source 51 is housed and in which an irradiation port 52a is formed, and an irradiation port cover 53 provided on the irradiation port 52a. The light source 51 generates light that cures the ink. The light source 51 is composed of, for example, a plurality of ultraviolet ray irradiating LEDs. The case 52 is configured in a box shape and houses the light source 51.

[0020] As shown in FIG. 3, the irradiation port 52a is provided on the lower surface of the case 52. The irradiation port 52a opens downward. The light emitted from the irradiation port 52a includes light directed downward and light directed diagonally downward. The main irradiation direction of the light emitted from the irradiation port 52a is downward. As shown in FIG. 2, the length of the irradiation port 52a in the main scanning direction is Ly. The length of the irradiation port 52a in the sub-scanning direction is Lx. The length Lx of the irradiation port 52a in the sub-scanning direction is longer than the length of the recording head 40 in the sub-scanning direction X.

[0021] The irradiation port cover 53 is provided so as to cover the irradiation port 52a. The irradiation port cover 53 is configured to be capable of transmitting the light generated by the light source 51. Here, the irradiation port cover 53 is a transparent plate-like cover that transmits light of a wavelength that hardens the ink. The irradiation port cover 53 is formed of, for example, a transparent glass plate.

[0022] The carriage moving device 60 is configured to move the carriage 30 in the main scanning direction Y. As shown in FIG. 1, the carriage moving device 60 includes a guide rail 61, a belt 62, left and right pulleys 63a and 63b, and a carriage motor 64. The carriage 30 is slidably engaged with the guide rail 61. The guide rail 61 extends in the left-right direction. The guide rail 61 guides the movement of the carriage 30 in the left-right direction. The belt 62 is fixed to the carriage 30. The belt 62 is an endless belt. The belt 62 is wound around a pulley 63a provided on the left side of the guide rail 61 and a pulley 63b provided on the right side. A carriage motor 64 is attached to the left pulley 63a. The carriage motor 64 is electrically connected to the control device 100. The carriage motor 64 is controlled by the control device 100. When the carriage motor 64 is driven, the pulley 63a rotates and the belt 62 runs. This causes the carriage 30 to move left and right along the guide rail 61.

[0023] The carriage moving device 60 is configured to be able to position the carriage 30 at a position facing the print area R1 and at a position facing an outer area R2 of the print area R1 by moving the carriage 30 in the main scanning direction Y. The carriage 30 passes above the print area R1, above an area R2a on the platen 20 that is an outer area of ​​the print area R1, and above an area R2b outside the platen 20 (more specifically, to the left and right of the platen 20) by being driven by the carriage moving device 60. In the present embodiment, a home position HP where the carriage 30 waits outside of printing time is set to the right of the platen 20 in the area R2b outside the platen 20. A maintenance space MS for performing maintenance on the carriage 30 is provided to the left of the platen 20 in the area R2b outside the platen 20.

[0024] The conveying device 70 moves the recording medium 5 on the platen 20 in the sub-scanning direction X. As shown in FIG. 1, the conveying device 70 includes a pinch roller 71, a grit roller 72, and a feed motor 73. The pinch roller 71 is provided above the platen 20 and presses down the recording medium 5 from above. The platen 20 is provided with the grit roller 72. The grit roller 72 is provided at a position facing the pinch roller 71. The grit roller 72 is connected to the feed motor 73 and rotates in the front-rear direction by receiving the driving force of the feed motor 73. The feed motor 73 is electrically connected to the control device 100 and is controlled by the control device 100. When the grit roller 72 rotates with the recording medium 5 sandwiched between the pinch roller 71 and the grit roller 72, the recording medium 5 is conveyed in the sub-scanning direction X.

[0025] As shown in FIG. 1, the capping device 80 is provided below the carriage 30 when it is located at the home position HP. The capping device 80 includes a cap 81, a cap moving device 82, and a suction pump 83. The cap 81 is configured in the shape of a container with a bottom and an open top. The cap 81 is made of, for example, rubber. The cap 81 is a member that protects the recording head 40 when not in use and prevents the ink in the recording head 40 from thickening and hardening due to irradiation of light. The cap moving device 82 moves the cap 81 in the vertical direction to bring it into contact with the recording head 40 or separate it from the recording head 40. The configuration of the cap moving device 82 is not particularly limited, but includes, for example, a drive motor and a ball screw (not shown).

[0026] The suction pump 83 is connected to the bottom of the cap 81. The suction pump 83 is configured to reduce the pressure in the internal space of the cap 81 when the cap 81 is in close contact with the recording head 40. The suction pump 83 is, for example, a tube pump. When the suction pump 83 is driven with the cap 81 in close contact with the recording head 40, ink is sucked out from the nozzles 41a of the recording head 40. The ink sucked by the suction pump 83 is discarded into a waste liquid tank (not shown) via a tube (not shown) or the like.

[0027] As shown in FIG. 1, the wiping device 90 is provided between the capping device 80 and the platen 20 in the main scanning direction Y. The wiping device 90 includes a wiper 91 and a wiper moving device 92. The wiper 91 is configured to be able to wipe the nozzle surface 41b (see FIG. 2) of the recording head 40. The wiper 91 is a flat plate-shaped member extending in the main scanning direction Y and the vertical direction Z. The upper edge of the wiper 91 is located slightly above the nozzle surface 41b of the recording head 40. The wiper 91 is made of, for example, rubber. Here, the wiper moving device 92 is configured to move the wiper 91 in the sub-scanning direction X. The wiping device 90 is configured to drive the wiper moving device 92 to bring the wiper 91 into contact with the nozzle surface 41b and wipe the nozzle surface 41b with the wiper 91 (hereinafter, also referred to as wiping). The suction of ink by the suction pump 83 and wiping is an example of cleaning the print head 40 .

[0028] As shown in Fig. 1, in this embodiment, the light quantity measuring device 150 is provided to the left of the printing area R1 in the outer area R2a of the printing area R1. As shown in Fig. 3, the light quantity measuring device 150 includes a hollow measurement box 160 partially embedded in the platen 20, an optical sensor 170 having a light receiving portion 171 provided inside the measurement box 160, and a shutter mechanism 180. The light quantity measuring device 150 is a device that measures the intensity of light irradiated by the light irradiation device 50 and reflected inside the measurement box 160 using the optical sensor 170.

[0029] As shown in FIG. 3, the measurement box 160 includes a wall portion 161 constituting an outer shape, an upper surface opening portion 162, and a reflecting plate 163. The wall portion 161 includes a bottom plate 161D, a left side plate 161L, a right side plate 161R, a front side plate 161F, and a rear side plate 161Rr. The bottom plate 161D is provided below the platen 20 and approximately parallel to the platen 20. The left side plate 161L, the right side plate 161R, the front side plate 161F, and the rear side plate 161Rr are connected to the left end, the right end, the front end, and the right end of the bottom plate 161D, respectively. The left side plate 161L, the right side plate 161R, the front side plate 161F, and the rear side plate 161Rr each extend upward and reach the lower surface of the platen 20. Here, a part of the platen 20 surrounded by the left side plate 161L, the right side plate 161R, the front side plate 161F, and the rear side plate 161Rr functions as a top surface that covers the upper surface of the measurement box 160. However, the measurement box 160 may have a top plate. Also, here, the entire measurement box 160 is embedded in the platen 20, but only a part of the measurement box 160 may be embedded in the platen 20. In that case, a top plate may be provided on a part of the upper surface of the measurement box 160 that is not covered by the platen 20. Furthermore, a part or all of the wall portion 161 of the measurement box 160 may be configured to be removable. The measurement box 160 only needs to be box-shaped at least when the light quantity measurement is performed. For example, a light sensor 170 is attached to the removable wall portion 161, and the light sensor 170 may be attached and detached to another wall portion 161 of the measurement box 160 together with the wall portion 161.

[0030] The upper surface of the measurement box 160 is an upper surface opening 162 through which light from the light irradiation device 50 enters. However, in this embodiment, the size of the opening through which the light from the light irradiation device 50 enters is substantially determined by the light collecting hole 21 provided in the platen 20. As shown in FIG. 2, the light collecting hole 21 is provided inside the measurement box 160 in a plan view. Hereinafter, the substantial opening of the measurement box 160 constituted by the upper surface opening 162 of the measurement box 160 and the light collecting hole 21 of the platen 20 is referred to as an opening 164. The opening 164 is provided in an area R2a on the support surface 20a of the platen 20 in the outer area R2 of the printing area R1. The opening 164 opens from near the right end of the measurement box 160 to the center in the left-right direction. The opening 164 opens upward.

[0031] As shown in FIG. 2, the opening 164 is provided on the movement path of the light irradiation device 50 by the carriage moving device 60 in a plan view. As a result, when the light irradiation device 50 is positioned above the opening 164 and irradiates light, the light from the light irradiation device 50 enters the opening 164. The opening 164 is configured to be larger than the irradiation port 52a of the light irradiation device 50 in a plan view. In detail, the length Ly1 of the opening 164 in the main scanning direction Y is configured to be longer than the length Ly of the irradiation port 52a in the main scanning direction Y, and the length Lx1 of the opening 164 in the sub-scanning direction X is configured to be longer than the length Lx of the irradiation port 52a in the sub-scanning direction X. However, the opening 164 may be the same size as the irradiation port 52a of the light irradiation device 50.

[0032] As shown in FIG. 3, the measurement box 160 has a reflector 163 on the inside of the wall 161. The reflector 163 is a part of a reflecting section that reflects light incident from the opening 164. The reflector 163 is disposed below the opening 164. As shown in FIG. 3, the reflector 163 is configured in a flat plate shape and is provided at an incline so as to connect the upper edge of the right side plate 161R and the bottom plate 161D. The reflector 163 is inclined so as to approach the left as it approaches the bottom. As shown in FIG. 2, the length of the reflector 163 in the sub-scanning direction X corresponds to the length of the bottom plate 161D in the sub-scanning direction X (i.e., the inside dimension of the measurement box 160 in the sub-scanning direction X). As shown in FIG. 3, the reflecting plate 163, together with the bottom plate 161D, the front plate 161F, parts of the rear plate 161Rr, the left plate 161L, and part of the platen 20 serving as the top surface of the measurement box 160, forms an internal space S1 of the measurement box 160.

[0033] In this embodiment, the reflecting portion that reflects the light incident from the opening 164 is made up of almost the entire surface of the wall portion that forms the internal space S1 (here, the bottom plate 161D, the front plate 161F, a part of each of the rear plate 161Rr, the left plate 161L, the reflecting plate 163, and a part of the platen 20). The wall portion that forms the internal space S1 is configured to reflect light well. Although the configuration for making the wall portion easily reflect light is not limited, the wall portion that forms the internal space S1 may be made of a material that easily reflects light, such as a mirror or polished metal. Such a material may be attached to the wall portion 161, the reflecting plate 163, and the platen 20 by means of adhesion or the like. The wall portion that forms the internal space S1 may be subjected to a surface treatment that easily reflects light, such as painting. Here, the part of the wall portion that forms the internal space S1 other than the part hidden by the light receiving portion 171 of the optical sensor 170 constitutes the reflecting portion. Hereinafter, the reflecting portion is represented by the reference symbol 165. The light reflectance of the reflecting portion 165 is preferably 50% or more. The light reflection by the reflecting portion 165 here includes specular reflection and diffuse reflection.

[0034] The reflecting portion 165 may constitute at least a part of the wall portion forming the internal space S1, and may not constitute all or almost all of the wall portion forming the internal space S1. A part of the wall portion forming the internal space S1 may not be configured to easily reflect light. Preferably, the surface area of ​​the reflecting portion 165 is 80% or more of the surface area of ​​the entire wall portion forming the internal space S1.

[0035] The optical sensor 170 has a light receiving unit 171 provided to face the internal space S1 of the measurement box 160, and a main body 172 connected to the light receiving unit 171. The optical sensor 170 measures the intensity of light received by the light receiving unit 171. Here, the intensity of light means the amount of light irradiated per predetermined time (instantaneous amount of light). The intensity of light may be defined, for example, by the irradiance of light (the energy of light irradiated per unit time to a unit area). Alternatively, the intensity of light may be defined by the radiance or radiant intensity of light. The definition of the intensity of light is not particularly limited as long as the same measurement method is used each time the measurement is performed. The integrated amount of light is obtained by integrating the intensity of light along the time axis. Here, the optical sensor 170 measures the intensity of light received by the light receiving unit 171 when the illuminance is 1 mW / cm 2 The device is configured to be able to measure the following light:

[0036] The light receiving unit 171 is provided to receive light incident from the opening 164 and reflected by the reflecting unit 165. Here, as shown in FIG. 3, the light receiving unit 171 is provided on a wall portion constituting the internal space S1, more specifically, on the lower surface of the platen 20 as the top surface of the measurement box 160. The light receiving unit 171 has a light receiving surface 171a that detects light, and the light receiving surface 171a faces downward. As shown in FIG. 2, the light receiving unit 171 is provided outside the opening 164 in a plan view so as not to directly receive the light incident on the opening 164. The light receiving unit 171 is also attached with the light receiving surface 171a facing downward so that the light incident on the opening 164 is not directly irradiated on the light receiving surface 171a, as shown in FIG. 3. In order not to directly receive light incident on the opening 164, it is preferable that the light receiving surface 171a is oriented in a direction perpendicular or at an acute angle to the downward direction (the opening direction of the irradiation port 52a of the light irradiation device 50), in other words, facing horizontally or downwardly from the horizontal.

[0037] However, the light receiving unit 171 only needs to be provided so as to face the internal space S1 of the measurement box 160, and the installation location, installation direction, etc. are not limited. For example, the light receiving unit 171 may be provided away from the wall portion that configures the internal space S1. Also, the light receiving unit 171 may be inserted from the outside of the measurement box 160 into a through hole provided in the wall portion 161, for example, and may not protrude into the internal space S1.

[0038] Here, the main body 172 of the optical sensor 170 is provided outside the measurement box 160. The optical sensor 170 including the main body 172 and the light receiving unit 171 and the measurement box 160 are provided below the support surface 20a of the platen 20. This allows the carriage 30 to pass above the measurement box 160 and the optical sensor 170. However, the main body 172 of the optical sensor 170 does not have to be provided on the movement path of the carriage 30, and in that case, may have a portion located above the support surface 20a. Here, the main body 172 includes a transmitter that transmits a signal corresponding to the intensity of the light received by the light receiving unit 171, and the like.

[0039] The shutter mechanism 180 is a mechanism for opening and closing the opening 164. The shutter mechanism 180 includes a shutter 181 capable of opening and closing the opening 164, and a shutter driver 182 for driving the shutter 181. As shown in FIG. 2 and FIG. 3, the shutter 181 is a flat plate-shaped member extending in the main scanning direction Y and the sub-scanning direction X. Here, the shutter 181 is provided substantially horizontally between the upper edge of the measurement box 160 and the lower surface of the platen 20. However, the location of the shutter 181 is not limited, and for example, the shutter 181 may be provided along the support surface 20a of the platen 20. The shutter driver 182 is configured to move the shutter 181 in the horizontal direction. The configuration of the shutter driver 182 is not limited, and the shutter driver 182 may include, for example, an air cylinder. The shutter mechanism 180 blocks the internal space S1 from the outside when the light quantity measurement device 150 is not measuring the quantity of light, thereby preventing ink, foreign matter, etc. from entering the internal space S1.

[0040] FIG. 4 is a block diagram of the printer 10. As shown in FIG. 4, the control device 100 is connected to a plurality of ink heads 41 (only one is shown in FIG. 4), a light source 51 of the light irradiation device 50, a carriage motor 64 of the carriage movement device 60, a feed motor 73 of the transport device 70, a cap movement device 82 and a suction pump 83 of the capping device 80, a wiper movement device 92 of the wiping device 90, and a shutter drive unit 182 of the shutter mechanism 180, and controls their operations. The control device 100 is also connected to an optical sensor 170 and receives a signal from the optical sensor 170. The control device 100 is, for example, a computer, and may include a central processing unit (hereinafter referred to as a CPU), a ROM in which a program executed by the CPU is stored, a RAM, and the like. Each unit of the control device 100 may be configured by software or hardware. The configuration of the control device 100 is not particularly limited.

[0041] 4, the control device 100 includes a scan control unit 101, a discharge control unit 102, an irradiation control unit 103, a transport control unit 104, a light amount acquisition unit 105, a threshold registration unit 106, a comparison unit 107, a light amount control unit 108, a stray light amount acquisition unit 109, a cleaning control unit 110, and a shutter control unit 111. The control device 100 may include other control units, but the description and illustration thereof will be omitted here.

[0042] The scanning control unit 101 controls the carriage moving device 60 to move the carriage 30 between a position facing the printing area R1 and a position facing the outer area R2 of the printing area R1. The scanning control unit 101 basically positions the carriage 30 at the home position HP except when printing. When printing, the scanning control unit 101 moves the carriage 30 within a range of the main scanning direction Y that includes at least the printing area R1. In this embodiment, the scanning control unit 101 moves the carriage 30 before printing starts, and positions the irradiation port 52a of the light irradiation device 50 above the opening 164. At this time, a status diagnosis of the light irradiation device 50 is performed.

[0043] The ejection control unit 102 controls the multiple ink heads 41 to eject ink toward the recording medium 5 supported by the platen 20. The ejection control unit 102 ejects ink toward a printing region R1 on the platen 20. The ejection control unit 102 thereby causes the ink to land on the recording medium 5 supported on the support surface 20a of the platen 20. An image is formed on the recording medium 5 in the printing region R1 by causing the ink to land on the recording medium 5 in the printing region R1 while moving the carriage 30 in the main scanning direction Y.

[0044] The irradiation control unit 103 controls the light irradiation device 50 to irradiate the platen 20 with light that hardens the ink. The irradiation control unit 103 thereby irradiates the ink that has landed on the recording medium 5 with light that hardens the ink. An image is fixed on the recording medium 5 in the printing area R1 by irradiating the ink on the printing area R1 with light while moving the carriage 30 in the main scanning direction Y. In this embodiment, the irradiation control unit 103 also causes the light irradiation device 50 to irradiate light when the irradiation port 52a of the light irradiation device 50 is positioned above the opening 164 before printing starts.

[0045] The transport control unit 104 controls the transport device 70 to transport the recording medium 5 on the platen 20 in the sub-scanning direction X. During printing, the transport control unit 104 intermittently moves the recording medium 5 in the sub-scanning direction X to update the portion of the recording medium 5 located on the print region R1x in the sub-scanning direction X, i.e., the portion where an image is to be formed. In this way, the entire image to be printed on the recording medium 5 is formed.

[0046] The light amount acquiring unit 105 is configured to acquire the intensity of light measured by the light sensor 170. Here, the light amount acquiring unit 105 acquires the intensity of light measured by the light sensor 170 when the light irradiation device 50 irradiates light with the irradiation port 52a of the light irradiation device 50 positioned directly above the opening 164. The printer 10 thereby diagnoses the state of the light irradiation device 50. The threshold value registering unit 106 registers a threshold value related to the intensity of light acquired by the light amount acquiring unit 105. The comparing unit 107 compares the intensity of light acquired by the light amount acquiring unit 105 with the threshold value registered in the threshold value registering unit 106. The printer 10 according to this embodiment is configured to intensify the light generated by the light source 51 when the intensity of light acquired by the light amount acquiring unit 105 is smaller than the threshold value. The light amount control unit 108 controls the light source 51 to intensify the light generated when the intensity of light acquired by the light amount acquiring unit 105 is smaller than the threshold value. The light amount control unit 108 increases the intensity of the light generated by the light source 51, for example, by increasing the current flowing through the light source 51.

[0047] The stray light amount acquiring unit 109 acquires the light intensity measured by the light sensor 170 when ink is ejected under the control of the ejection control unit 102 and light is irradiated under the control of the irradiation control unit 103, that is, during printing. During printing, the carriage 30 is located at a position facing the printing region R1, and the light irradiation device 50 irradiates light. The stray light amount acquiring unit 109 acquires the light intensity measured by the light sensor 170 in this state. The stray light amount acquiring unit 109 also calculates the integrated light amount from the acquired light intensity (instantaneous light amount). The printer 10 according to this embodiment is configured to clean the ink head 41 after printing is completed when the integrated light amount acquired by the stray light amount acquiring unit 109 exceeds a predetermined threshold value. This cleaning is intended to prevent the ink in the ink head 41 from thickening and hardening due to the light (stray light) reflected by each part of the printer 10 of the light irradiated from the light irradiation device 50 being irradiated to the ink head 41. The light amount acquired by the stray light amount acquisition unit 109 represents the amount of stray light, since it is not the amount of light when light is directly irradiated onto the opening 164. Therefore, when the integrated light amount acquired by the stray light amount acquisition unit 109 exceeds a predetermined threshold, the printer 10 according to this embodiment presumes that the amount of stray light has reached a certain level, and performs cleaning of the ink head 41.

[0048] When the integrated light amount acquired by the stray light amount acquisition unit 109 exceeds a predetermined threshold, the cleaning control unit 110 controls the cap moving device 82 after printing to attach the cap 81 to the recording head 40. With the cap 81 attached to the recording head 40, the cleaning control unit 110 drives the suction pump 83 to suck ink from the multiple nozzles 41a. The cleaning control unit 110 further controls the wiper moving device 92 to cause the wiper 91 to wipe the nozzle surface 41b. This cleans the ink head 41.

[0049] The shutter control unit 111 controls the shutter drive unit 182 to close the opening 164 by the shutter 181 when the light quantity measurement device 150 is not measuring the quantity of light. In addition, the shutter control unit 111 controls the shutter drive unit 182 to move the shutter 181 and open the opening 164 when the light quantity measurement device 150 is measuring the quantity of light.

[0050] The following describes an example of a process for diagnosing the state of the light irradiation device 50 and measuring the amount of stray light. However, the process described below is merely an example, and does not limit the process for diagnosing the state of the light irradiation device 50 and measuring the amount of stray light.

[0051] FIG. 5 is a flow chart showing an example of a process of diagnosing the state of the light irradiation device 50 and measuring the amount of stray light. As shown in FIG. 5, in the example shown here, the state diagnosis of the light irradiation device 50 is performed before printing an image. As shown in FIG. 5, in step S01, the shutter 181 is opened. In the following step S02, the carriage 30 is moved so that the irradiation port 52a of the light irradiation device 50 is located directly above the opening 164. In step S03, the light irradiation device 50 is caused to irradiate light in this state. As a result, the light from the light irradiation device 50 is directly incident on the opening 164. This light is reflected by the reflecting portion 165 in the measurement box 160 (some of the light is reflected once, some of the light is reflected multiple times), and then reaches the light receiving portion 171 of the light sensor 170.

[0052] FIG. 6 is a schematic diagram showing the distribution of irradiance on the wall part on which the light receiving unit 171 is installed among the walls of the measurement box 160. Here, the wall part on which the light receiving unit 171 is installed is the top surface (the lower surface of the platen 20) of the measurement box 160. In FIG. 6, the wall part on which the light receiving unit 171 is installed is divided into a plurality of grids, and the light intensity is illustrated for each grid. The light intensity is represented by the density of hatching, and fine hatching indicates a high light intensity. Hatching with a wide line spacing indicates a low light intensity. However, grids with a low light intensity below a certain level are not hatched. As shown in FIG. 6, in the example shown here, the light intensity is high at the center of the wall part on which the light receiving unit 171 is installed, and the light intensity becomes weaker as it moves away from the center. The light receiving unit 171 of the optical sensor 170 is provided in this central part where the light is strong.

[0053] According to an experiment by the inventor of the present application, the light intensity distribution as shown in FIG. 6 is generally maintained even if a part of the light source 51 of the light irradiation device 50 is turned off. This is because the light intensity is averaged in the process of reflection until it reaches the light receiving unit 171, and the difference in light intensity depending on the location of the irradiation port 52a is buried. When a part of the light source 51 of the light irradiation device 50 is turned off, the light intensity distribution as shown in FIG. 6 is generally maintained, but the intensity of the light received by the light receiving unit 171 becomes weaker. Therefore, when the averaged light intensity measured by the light sensor 170 decreases, it can be determined that at least a partial decrease in the light amount of the light irradiation device 50 has occurred. This is a diagnosis that is possible by reflecting light inside the partitioned measurement box 160, and is a diagnosis result that cannot be obtained by mainly measuring the light amount directly. In this embodiment, the light sensor 170 detects an illuminance of 1 mW / cm 2 In other words, the optical sensor 170 is configured to be able to measure light with an illuminance of 1 mW / cm 2 It has a measurement resolution of 1mW / cm 2 By being able to detect the following slight changes in illuminance, the printer 10 can also detect slight changes in the state of the light irradiation device 50.

[0054] In this embodiment, in the state diagnosis of the light irradiation device 50, the opening 164 of the measurement box 160 is irradiated with direct light from the light irradiation device 50. This stabilizes the manner in which light is incident into the internal space S1 of the measurement box 160, and as a result, the measurement conditions of the reflected light are also stabilized. For this reason, in this embodiment, the opening 164 is provided on the movement path of the light irradiation device 50 in a plan view and opens upward. This allows the opening 164 to be irradiated with direct light from the light irradiation device 50.

[0055] Further, here, the opening 164 is configured to be larger than the irradiation port 52a of the light irradiation device 50 in a plan view. Therefore, when the light amount decreases in a part of the irradiation port 52a of the light irradiation device 50, the light of the part where the light amount has decreased is surely incident on the opening 164. Therefore, it is possible to discover that the light amount has decreased in a part of the irradiation port 52a of the light irradiation device 50. Note that, as described above, the opening 164 may be configured to be the same size as the irradiation port 52a of the light irradiation device 50 in a plan view.

[0056] On the other hand, in this embodiment, the arrangement of the light receiving unit 171 is taken into consideration so that the light receiving surface 171a of the light receiving unit 171 is not irradiated with direct light. Here, the light receiving unit 171 is provided outside the opening 164 in a plan view. Furthermore, the light receiving surface 171a of the light receiving unit 171 faces in a direction that forms a right angle or an acute angle with respect to the downward direction, which is the main irradiation direction of direct light, and faces downward in this case. This prevents the light receiving surface 171a from being irradiated with direct light.

[0057] Furthermore, in this embodiment, the light receiving unit 171 is provided on the wall portion constituting the internal space S1 of the measurement box 160, and the light receiving unit 171 faces the entire internal space S1. This reduces bias in the received light. Also, by increasing the proportion of the reflecting unit 165 in the wall portion constituting the internal space S1 of the measurement box 160 (preferably 80% or more), the number of times the light is reflected by the reflecting unit 165 before reaching the light receiving unit 171 is increased, and the light intensity is averaged.

[0058] As shown in Fig. 5, in the next step S04, the measurement value M1 of the light intensity by the optical sensor 170 is compared with a predetermined threshold value V1. If the measurement value M1 by the optical sensor 170 is equal to or greater than the threshold value V1 (if the result of step S04 is YES), the condition of the light irradiation device 50 is diagnosed as being OK. In this case, the process proceeds to step S05, and printing is started. If the measurement value M1 by the optical sensor 170 is smaller than the threshold value V1 (if the result of step S04 is NO), it is diagnosed that the amount of light of the light irradiation device 50 is reduced. In this case, in step S10, the light generated by the light source 51 is intensified.

[0059] In step S10, for example, the output of the light source 51 is increased so as to add the proportion or amount of the measurement value M1 that is insufficient with respect to a reference value set to be greater than the threshold value V1. By such control, the light amount of the light irradiation device 50 that has decreased due to deterioration or the like can be returned to an appropriate light amount. After the light amount of the light irradiation device 50 is increased in step S10, step S04 is repeated again. Note that, if the difference between the measurement value M1 and the threshold value V1 is greater than a predetermined value, the printer 10 may issue an error message without adjusting the output of the light source 51. Also, if the number of times the output adjustment of the light source 51 has been performed reaches a predetermined number, the printer 10 may determine that the output adjustment of the light source 51 is impossible and issue an error message.

[0060] In the printing of step S05, the light irradiation device 50 irradiates light for curing the ink, which is omitted in FIG. 5. In step S06, it is determined whether the integrated light amount Q1 of the stray light, which continues to be integrated during printing, exceeds a predetermined threshold value Vq. If the integrated light amount Q1 of the stray light during printing does not exceed the threshold value Vq (if the result of step S06 is YES), it is selected in step S07 not to clean the ink head 41 after printing. If the integrated light amount Q1 of the stray light during printing exceeds the threshold value Vq (if the result of step S06 is NO), it is selected in step S08 to clean the ink head 41 after printing. In either case of step S07 or S08, the shutter 181 is closed in the following step S09. This prevents ink or foreign matter from entering the inside of the measurement box 160 and affecting the light amount measurement.

[0061] In this embodiment, the measurement box 160 (or a part of it) is embedded in the platen 20, and the opening 164 is provided in an area R2a on the platen 20 outside the printing area R1, thereby reducing the space required to install the measurement box 160 and the movable range required for the carriage 30. In this case, the measurement box 160 and the light receiving unit 171 are disposed below the support surface 20a of the platen 20 so as not to interfere with the movement of the carriage 30.

[0062] [Modification of the first embodiment] In one preferred variant of the first embodiment, the printer operates differently when the measurement value from the optical sensor is less than the threshold value (in FIG. 5, the result of step S04 is NO) and it is diagnosed that the amount of light from the light irradiation device is low. Except for this operation, the configuration of the printer in the following variants is the same as that of the first embodiment. Therefore, in the following explanation of the variants, components that perform functions common to the first embodiment will be given the same reference numerals as in the first embodiment, and duplicate explanations will be omitted or simplified. The same applies to the other embodiments described hereinafter.

[0063] FIG. 7 is a block diagram of the printer 10 according to a modification of the first embodiment. As shown in FIG. 7, the control device 100 of the printer 10 according to this modification includes another threshold registration unit 106A (hereinafter, simply referred to as the threshold registration unit 106A) instead of the threshold registration unit 106, another comparison unit 107A (hereinafter, simply referred to as the comparison unit 107A) instead of the comparison unit 107, and a warning unit 108A instead of the light quantity control unit 108. The threshold registration unit 106A has a threshold V2 related to the intensity of light acquired by the light quantity acquisition unit 105 registered therein. This threshold V2 may be the same as the threshold V1 registered in the printer 10 according to the first embodiment, or may be different. The comparison unit 107A compares the intensity of light acquired by the light quantity acquisition unit 105 with the threshold V2. The warning unit 108A is configured to issue a warning to prompt cleaning of the irradiation port cover 53 when the intensity of light acquired by the light quantity acquisition unit 105 is smaller than the threshold V2.

[0064] According to the above configuration, if the reason why the light intensity acquired by the light amount acquisition unit 105 is smaller than the threshold value V2 is due to dirt on the irradiation port cover 53, the user will notice this, and the problem of reduced light amount can be easily solved. In addition, it is possible to prevent the life of the light source 51 from being shortened or the light intensity from being too strong by increasing the output of the light source 51 when the irradiation port cover 53 is simply dirty.

[0065] If the same warning is issued even after the irradiation port cover 53 has been cleaned, the printer 10 may issue an error message. In addition, both the warning according to this modified example and the increase in the light amount of the light source 51 according to the first embodiment may be performed. For example, in one preferred example, if the light intensity acquired by the light amount acquisition unit 105 is smaller than a threshold value, a warning may be issued to prompt the user to clean the irradiation port cover 53. After that, the user may input that the cleaning of the irradiation port cover 53 has been completed. Then, the light amount measurement device 150 again measures the light amount (for example, the same steps as S01 to S04 in FIG. 5), and if the light intensity acquired by the light amount acquisition unit 105 is still smaller than the threshold value, the output of the light source 51 may be increased.

[0066] [Second embodiment] In the second embodiment, the measurement box 160 and the light sensor 170 are unitized and configured to be detachably attached to the printer 10. FIG. 8 is a partially cutaway front view of the printer 10 according to the second embodiment. As shown in FIG. 8, the printer 10 according to this embodiment includes a light amount measuring unit 150A including the measurement box 160, the light sensor 170, and the shutter 181. The light amount measuring unit 150A is configured to be detachably attached to the printer 10. Note that the light amount measuring unit 150A only needs to include at least the measurement box 160 and the light sensor 170, and may not include the shutter 181. In this embodiment, the light amount measuring unit 150A is set in the printer 10 by a user or the like when in use, and the shutter 181 is opened and closed manually by the user or the like.

[0067] As shown in FIG. 8, in this embodiment, the measurement box 160 is disposed outside the platen 20, specifically, to the left of the platen 20. However, the measurement box 160 may be disposed to the right of the platen 20. A positioning mechanism (not shown) for setting the measurement box 160 at a predetermined installation position is provided in the maintenance space MS to the left of the platen 20. The measurement box 160 here has a top plate 161U. The top plate 161U is formed with an opening 164 that opens in the up-down direction Z. When the measurement box 160 is set at a predetermined installation position, the opening 164 is located directly below the movement path of the light irradiation device 50 by the carriage movement device 60, as in the first embodiment. The internal configuration of the measurement box 160 may be the same as that of the first embodiment.

[0068] According to this configuration, the light quantity measuring unit 150A including the measurement box 160 and the light sensor 170 can be attached and detached to the printer 10, so that a place that is usually used for other purposes (for example, the maintenance space MS) can be used as the installation location of the light quantity measuring unit 150A only when performing light quantity measurement. Therefore, the space of the printer 10 can be used effectively. Such a detachable light quantity measuring unit 150A can be suitably used for, for example, regular or irregular maintenance, inspection by a serviceman, etc. Also, even if the light quantity measuring unit 150A is not detachable from the printer 10, if the measurement box 160 is provided outside the platen 20, the installation and inspection of the light quantity measuring device 150 can be easily performed.

[0069] Above, several preferred embodiments have been described. However, the printer of the present invention is not limited to the above-mentioned embodiments, and can be implemented by other embodiments. For example, the configuration inside the measurement box 160 can be variously configured. Figures 9 and 10 are cross-sectional views showing a modified internal configuration of the measurement box 160. As shown in Figure 9, in this modified example, the reflecting section 165 does not include a reflecting plate diagonally bridged between the side plate and the bottom plate, and the internal space S1 is configured as a substantially rectangular parallelepiped. In this modified example, the light receiving section 171 of the optical sensor 170 is provided on the left side plate 161L, and the light receiving surface 171a faces the horizontal direction (the direction perpendicular to the vertical direction Z, which is the main irradiation direction of the light). The light receiving section 171 is also provided in a position offset from directly below the opening 164. For example, even with such a configuration, the intensity of the reflected light inside the measurement box 160 of the light from the light irradiation device 50 can be measured.

[0070] In the modified example of FIG. 9, the other light receiving unit 171B is also provided facing the internal space S1 of the measurement box 160. In this way, the number of light sensors is not limited to one. The light sensor related to the other light receiving unit 171B may be used auxiliary to check the reliability of the light sensor 170 (for example, to check whether it is broken). Alternatively, the light sensor related to the other light receiving unit 171B may be used in the same way as the light sensor 170, and when the amount of received light falls below a predetermined threshold, the output of the light source 51 may be adjusted or a warning may be issued.

[0071] In the modification shown in FIG. 10, the reflecting portion 165 has a substantially cylindrical surface 165a that is substantially circular (but is interrupted at the opening 164) when viewed in the front-rear direction. Such a substantially cylindrical surface 165a makes it easy to concentrate the reflected light of the light incident from the opening 164 at a specific location on the substantially cylindrical surface 165a. Therefore, as shown in FIG. 10, by providing the light receiving portion 171 at the specific location P1, the light receiving portion 171 can receive stronger and less biased reflected light. Therefore, the measurement accuracy of the optical sensor 170 can be improved. The curved surface portion 165a of the reflecting portion 165 may be formed, for example, in a substantially elliptical shape, a hyperbola, or another curved shape when viewed in the front-rear direction.

[0072] In addition, unless otherwise specified, the above-mentioned embodiment does not limit the present invention. For example, the opening direction of the opening of the measurement box may not be substantially parallel to the opening direction of the irradiation port of the light irradiation device. In addition, the opening of the measurement box may not be provided on the moving path of the irradiation port when viewed from the opening direction of the irradiation port. For the state diagnosis of the light irradiation device, the opening is only required to be configured so that direct light from the light irradiation device is incident, and is not further limited.

[0073] Furthermore, the opening of the measurement box may not be provided in the light irradiation direction from the irradiation port of the light irradiation device. For example, the opening of the measurement box may be provided above the irradiation port even if the irradiation port of the light irradiation device opens downward. In this case, reflected light from each part of the printer enters the inside of the measurement box, but if the measurement conditions are stable, it is possible to diagnose the state of the light irradiation device. In addition, stray light can be easily measured. In order to measure the amount of stray light, the opening only needs to have a direction and size in which stray light enters, and is not particularly limited beyond that.

[0074] The configuration of the printer is not particularly limited, and the printer may be, for example, a so-called flatbed printer. [Explanation of symbols]

[0075] 5 Recording media 10 Printers 20 Platen 20a Support surface 21 Lighting hole (opening) 30 Carriage 41 Ink head 50 Light irradiation device 51 Light source 52a Irradiation port 53 Irradiation port cover 60 Carriage moving device 100 Control device 101 Scanning control section 102 Discharge control section 103 Irradiation control unit 105 Light intensity acquisition section 106 Threshold registration unit (first threshold registration unit) 106A Threshold registration unit (second threshold registration unit) 107 Comparison section (first comparison section) 107A Comparison section (2nd comparison section) 108 Light quantity control section 108A Warning part 109 Stray light amount acquisition unit 150 Light quantity measuring device 150A Light quantity measurement unit (measurement unit) 160 Measurement Box 161 Wall 163 Reflector 164 Opening 165 Reflector 170 Optical Sensor 171 Light receiving section 171a Photosensitive surface 181 Shutter R1 print area R2 outer area R2a Outer area (on the platen) R2b Outer area (outside the platen) S1 interior space Y Main scanning direction (orthogonal direction) U upward (first direction) D Downward (second direction)

Claims

1. An ink head that ejects photocurable ink; a light irradiation device that irradiates light to cure the ink; a measurement box having an opening and an internal space; an optical sensor having a light receiving portion provided to face the internal space of the measurement box and measuring the intensity of light received by the light receiving portion; a carriage that holds the light irradiation device in a first direction from the measurement box; a carriage moving device that moves the carriage in a direction perpendicular to the first direction, The measurement box further includes a reflecting portion provided in the internal space and configured to reflect light incident through the opening portion, the light receiving portion is provided to receive light incident through the opening portion and reflected by the reflecting portion, The light irradiation device includes an irradiation port that opens toward a second direction that is an opposite direction to the first direction, the opening is disposed on a path of movement of the light irradiation device by the carriage movement device when viewed in the first direction, and is open toward the first direction. Printer.

2. An ink head that ejects photocurable ink; a light irradiation device that irradiates the ink with light to cure the ink; a measurement box having an opening and an internal space; a light sensor having a light receiving portion provided so as to face the internal space of the measurement box and measuring the intensity of light received by the light receiving portion; The light irradiation device is provided in a first direction from the measurement box, The light irradiation device includes an irradiation port that opens toward a second direction that is an opposite direction to the first direction, The opening portion is open toward the first direction, The measurement box further includes a reflecting portion provided in the internal space and configured to reflect light incident through the opening portion, the light receiving portion is provided to receive light incident through the opening portion and reflected by the reflecting portion, The light receiving unit is provided outside the opening when viewed in the first direction. Printer.

3. The light receiving unit has a light receiving surface for detecting light, The light receiving surface faces in a direction perpendicular or acute to the second direction.

3. The printer according to claim 1 or 2.

4. The opening is the same size as the irradiation port or larger than the irradiation port when viewed in the first direction. The printer according to any one of claims 1 to 3.

5. a support table having a support surface for a recording medium on which a printing area is set and provided in the second direction from the light irradiation device; The opening is provided outside the printing area when viewed in the first direction. The printer according to any one of claims 1 to 4.

6. The measurement box and the light receiving unit are provided in the second direction from the support surface. The printer according to claim 5.

7. At least a portion of the measurement box is embedded in the support base, The opening is provided on the support surface and outside the printing area.

7. The printer according to claim 5 or 6.

8. An ink head that ejects photocurable ink; a light irradiation device that irradiates the ink with light to cure the ink; a measurement box having an opening and an internal space; an optical sensor having a light receiving portion provided to face the internal space of the measurement box and measuring the intensity of light received by the light receiving portion; a control device connected to the optical sensor, The measurement box further includes a reflecting portion provided in the internal space and configured to reflect light incident through the opening portion, the light receiving portion is provided to receive light incident through the opening portion and reflected by the reflecting portion, The light irradiation device is a light source that generates light for curing the ink; An illumination port provided with a cover through which light generated by the light source can pass, The control device includes: a light amount acquiring unit that acquires the light intensity measured by the light sensor; a threshold registration unit in which a threshold value related to the intensity of the light acquired by the light amount acquisition unit is registered; a comparison unit that compares the intensity of the light acquired by the light amount acquisition unit with the threshold value; and a warning unit that issues a warning to prompt cleaning of the cover when the intensity of the light acquired by the light amount acquisition unit is smaller than the threshold value. Printer.

9. An ink head that ejects photocurable ink; a light irradiation device that irradiates the ink with light to cure the ink; a support table for supporting a recording medium, the support table being disposed opposite the ink head and the light irradiation device; a measurement box having an opening and an internal space; an optical sensor having a light receiving portion provided to face the internal space of the measurement box and measuring the intensity of light received by the light receiving portion; a control device connected to the ink head, the light irradiation device, and the light sensor; The measurement box further includes a reflecting portion provided in the internal space and configured to reflect light incident through the opening portion, the light receiving portion is provided to receive light incident through the opening portion and reflected by the reflecting portion, The control device includes: an ejection control unit that controls the ink head to eject the ink onto the recording medium supported by the support table; an irradiation control unit that controls the light irradiation device to irradiate the support table with light for curing the ink; a stray light amount acquisition unit that acquires the intensity of light measured by the optical sensor when the ink is ejected under the control of the ejection control unit and light is irradiated under the control of the irradiation control unit, Printer.

10. An ink head that ejects photocurable ink; a light irradiation device that irradiates the ink with light to cure the ink; a measurement box having an opening and an internal space; an optical sensor having a light receiving portion provided to face the internal space of the measurement box and measuring the intensity of light received by the light receiving portion; a shutter capable of opening and closing the opening, The measurement box further includes a reflecting portion provided in the internal space and configured to reflect light incident through the opening portion, The light receiving portion is provided to receive light incident through the opening portion and reflected by the reflecting portion. Printer.

11. An ink head that ejects photocurable ink; a light irradiation device that irradiates the ink with light to cure the ink; a measurement box having an opening and an internal space; a light sensor having a light receiving portion provided so as to face the internal space of the measurement box and measuring the intensity of light received by the light receiving portion; The measurement box further includes a reflecting portion provided in the internal space and configured to reflect light incident through the opening portion, the light receiving portion is provided to receive light incident through the opening portion and reflected by the reflecting portion, The light irradiation device irradiates the opening with direct light. Printer.

12. The light receiving unit is provided on a wall portion that constitutes the internal space. The printer according to any one of claims 1 to 11.

13. The optical sensor is configured to be capable of measuring light having an illuminance of 1 mW / cm2 or less. The printer according to any one of claims 1 to 12.

14. A control device connected to the light irradiation device and the light sensor is further provided. The control device includes: a light amount acquiring unit that acquires the light intensity measured by the light sensor; a control threshold registering unit in which a control threshold related to the intensity of the light acquired by the light amount acquiring unit is registered; an intensity comparison unit that compares the light intensity acquired by the light amount acquisition unit with the control threshold; and a light amount control unit that controls the light irradiation device to increase the intensity of the light when the intensity of the light acquired by the light amount acquisition unit is smaller than the control threshold value. The printer according to any one of claims 1 to 13.

15. a measurement unit that is detachable from the printer and includes at least the measurement box and the optical sensor; The printer according to any one of claims 1 to 14.

Images