JP2019018411A - Liquid discharge device and detection method for interference object - Google Patents

Abstract

To highly accurately detect whether or not an interference object exists on a support part even when a medium is swollen.SOLUTION: A liquid discharge device 1 comprises: a discharge part 7 capable of discharging liquid; a support part 4 supporting a medium onto which the liquid is discharged and being movable in a movement direction A; and a detection part 10 detecting whether or not an interference object being an object which interferes with the discharge part 7 exists on the support part 4. The detection part 10 is constituted so as to be movable in a facing direction C being a direction in which the support part 4 and the discharge part 7 face each other. By configuring the liquid discharge device 1 as described above, whether or not the interference object exists on the support part 4 can be highly accurately detected even when the medium is swollen.SELECTED DRAWING: Figure 5

Description

  The present invention relates to a liquid ejection apparatus and an interference detection method.

Conventionally, liquid ejecting apparatuses having various configurations have been used. Among such liquid ejecting apparatuses, for example, a liquid ejecting apparatus that forms an image by ejecting a liquid such as ink from the ejecting section to a medium supported by a support section is used.
For example, Patent Document 1 discloses an ink jet printer (liquid ejection device) capable of forming an image by ejecting ink from a print head (ejection unit) to a printing medium (medium) supported by a platen (support unit). ) Is disclosed.

JP 2003-311938 A

In a liquid ejection apparatus configured to eject an image from a ejection unit to a medium supported by a support unit, foreign matter adhered to the medium or interference such as wrinkles generated on the medium interferes with the ejection unit. There is a case. Therefore, the ink jet printer disclosed in Patent Document 1 includes a sensor (detection unit) capable of detecting an interference object in order to suppress the interference object from interfering with the print head.
In recent years, various types of media have been used, and in some cases, the liquid is discharged onto a medium that easily swells when the liquid is applied thereto. However, when a medium that easily swells is used, in the inkjet printer disclosed in Patent Document 1, the range in which the interference is to be detected deviates from the detection range of the sensor due to the swelling of the medium, and the interference is present on the support. In some cases, it could not be detected.
As described above, in the conventional liquid ejecting apparatus disclosed in Patent Document 1, it is possible to detect whether or not the interference exists on the support portion with high accuracy when the medium swells. It wasn't.

  Therefore, an object of the present invention is to detect whether or not an interference exists on a support portion with high accuracy even when the medium swells.

  The liquid ejection apparatus according to the first aspect of the present invention for solving the above-described problem includes a ejection unit capable of ejecting a liquid, and a support unit that supports the medium from which the liquid is ejected and is movable along a movement direction. And a detection unit that detects whether or not an interfering object that is an object that interferes with the discharge unit exists on the support unit, wherein the support unit and the discharge unit are opposed to each other. It is configured to be movable in the opposite direction, which is the direction in which it moves.

  According to this aspect, since the detection unit is configured to be movable in the opposite direction, even when the medium swells, the interference unit exists on the support unit with high accuracy by moving the detection unit in the opposite direction. Whether or not to do so can be detected.

  The liquid ejection apparatus according to a second aspect of the present invention is the liquid ejection device according to the first aspect, based on setting information which is information set on an image formed on the medium by ejecting the liquid from the ejection unit. A control unit that controls movement of the detection unit is provided.

  According to this aspect, since the movement of the detection unit is controlled based on the setting information, the degree of swelling of the medium can be predicted from the setting information, and whether or not the interference exists on the support unit easily and with high accuracy. Can be detected.

  The liquid ejection apparatus according to a third aspect of the present invention is characterized in that, in the second aspect, the setting information includes information on the type of the medium.

  According to this aspect, since the setting information includes information on the type of medium, it is determined whether the medium is easily swelled or difficult to swell, and the degree of swelling of the swelled medium is predicted and the detection unit is moved. It is possible to detect whether or not the interference exists on the support portion with particularly high accuracy.

  The liquid ejection apparatus according to a fourth aspect of the present invention is characterized in that, in the second or third aspect, the setting information includes information on the application amount of the liquid per unit area to the medium.

  According to this aspect, since the setting information includes information on the amount of liquid applied to the medium per unit area, the detection unit can be moved after predicting how much the swelling medium swells, and the interfering object can be obtained with particularly high accuracy. It can be detected whether or not exists on the support portion.

  The liquid ejection apparatus according to a fifth aspect of the present invention is the liquid ejection device according to any one of the second to fourth aspects, wherein the image is formed by superimposing a plurality of image forming layers including at least a layer formed using the liquid. The setting information is configured to be formed on the medium, and the setting information includes information on the number of layers constituting the image forming layer.

  In a configuration in which an image can be formed on a medium by superimposing a plurality of image forming layers, the degree of swelling of the medium may change every time each layer is formed. According to this aspect, since the setting information includes information on the number of layers constituting the image forming layer, the detection unit can be moved after predicting how much the swelling medium swells at the time of forming each layer, In particular, it is possible to detect whether or not an interfering object exists on the support portion with high accuracy.

  The liquid ejection device according to a sixth aspect of the present invention is the liquid ejection device according to any one of the second to fifth aspects, wherein the support portion has a set position where the medium is set along the moving direction; The discharge portion is movable between a discharge start position at which the discharge of the liquid by the discharge portion is started, and the discharge portion is an end portion on the set position side of the support portion at the set position in the movement direction. And the end of the support portion at the discharge start position on the discharge start position side can discharge the liquid to the medium, and the control unit supports the medium. It is possible to perform a discharge operation for discharging the liquid from the discharge unit to the medium by moving the portion from the discharge start position toward the set position along the moving direction, and the discharge operation is performed a plurality of times. 1st discharge The detection is performed such that the distance in the facing direction between the detection unit and the support unit during the second ejection operation is longer than the distance in the facing direction between the detection unit and the support unit during operation. The part is moved.

  If the discharge operation of discharging the liquid from the discharge unit to the medium is performed a plurality of times by moving the support unit supporting the medium along the moving direction, the second discharge operation is more than the first discharge operation. More often the medium is swollen. According to this aspect, the detection unit is moved so that the distance in the facing direction between the detection unit and the support unit becomes longer during the second discharge operation than during the first discharge operation. Even when the medium is swollen more during the second ejection operation than when the interference is present, it is possible to detect whether or not the interference exists on the support portion with particularly high accuracy.

  The liquid ejection device according to a seventh aspect of the present invention is the liquid ejection device according to any one of the first to sixth aspects, wherein the movement range of the detection unit in the facing direction is the support unit and the ejection unit in the facing direction. It is characterized by including the opposing range.

  According to this aspect, since the moving range in the facing direction of the detection unit includes the facing range of the support unit and the ejection unit in the facing direction, the medium supported by the support unit swells to which range of the facing range. In addition, the detection unit can move according to the degree of swelling of the medium, and can detect whether or not the interference exists on the support unit with high accuracy.

  According to an eighth aspect of the present invention, there is provided a method for detecting an interfering substance, a discharge unit capable of discharging a liquid, a support unit that supports a medium from which the liquid is discharged and is movable along a moving direction, and the discharge unit. A detecting unit that detects whether or not an interfering object that is an object that interferes with the detecting unit is present on the support unit. Based on setting information which is information set about an image formed on the medium by discharging the liquid, the detection unit is moved in a facing direction in which the support unit and the discharging unit are opposed to each other. Features.

  According to this aspect, since the detection unit is moved based on the setting information, the degree of swelling of the medium can be predicted from the setting information, and it is detected whether or not the interference exists on the support unit with high accuracy. be able to.

1 is a schematic perspective view illustrating a printing apparatus according to an embodiment of the present invention. 1 is a schematic front view illustrating a printing apparatus according to an embodiment of the present invention. 1 is a schematic plan view illustrating a printing apparatus according to an embodiment of the present invention. 1 is a block diagram of a printing apparatus according to an embodiment of the present invention. 1 is a schematic side view showing a main part of a printing apparatus according to an embodiment of the present invention. 1 is a schematic side view showing a main part of a printing apparatus according to an embodiment of the present invention. 1 is a schematic side view showing a main part of a printing apparatus according to an embodiment of the present invention. 1 is a schematic side view showing a main part of a printing apparatus according to an embodiment of the present invention.

Hereinafter, a printing apparatus 1 as a liquid ejection apparatus according to an embodiment of the present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a schematic perspective view of a printing apparatus 1 according to the present embodiment, showing a state in which a medium support unit 2 is at a printing start position. FIG. 2 is a schematic front view of the printing apparatus 1 of the present embodiment. FIG. 3 is a schematic plan view of the printing apparatus 1 of the present embodiment, showing a state in which the medium support unit 2 is at the medium setting position. In addition, in all of FIGS. 1 to 3, some components are simplified.

The printing apparatus 1 according to this embodiment includes a medium support unit 2. The medium support unit 2 includes a tray 4 as a support portion, and the tray 4 has a support surface 8 that supports the medium. The medium support unit 2 moves in the movement direction A while the medium is supported by the support surface 8 of the tray 4.
The printing apparatus 1 also includes a medium transport unit 3 that transports the medium supported by the tray 4 in the movement direction A. The moving direction A is a direction including a direction A1 and a direction A2 opposite to the direction A1.

  The medium support unit 2 is detachably mounted on the stage 5. Here, the attachment / detachment direction of the medium support unit 2 with respect to the stage 5 is the vertical direction in the printing apparatus 1 of the present embodiment. By rotating the lever 9, the medium support unit 2 moves together with the stage 5 in a direction (vertical direction) along a facing direction C described later. As shown in FIG. 2, the lever 9 is provided on the arm portion 11. As the medium, various materials such as textiles (woven fabric, cloth, etc.), paper, vinyl chloride resin can be used.

Further, inside the main body of the printing apparatus 1, a print head 7 serving as a discharge unit that can print ink (form an image) on a medium by discharging ink as an example of a liquid from a nozzle (not shown). Is provided. The printing apparatus 1 according to the present embodiment performs printing while reciprocating the print head 7 in the scanning direction B by reciprocating the carriage 6 holding the print head 7 in the scanning direction B intersecting the movement direction A. Ink is ejected from the head 7 onto the medium supported by the tray 4 to form a desired image.
In the printing apparatus 1 of the present embodiment, the front side (lower left direction) in FIG. 1 is the medium setting position 14 on the tray 4 (see FIG. 3). Then, after moving the tray 4 in which the medium is set in the direction A1 of the movement direction A to the print start position on the back side (upper right direction) in FIG. 1, the tray 4 is moved in the direction A2 of the movement direction A. While printing.
In addition to the print head 7, a pretreatment agent application unit that can apply the pretreatment agent to the medium prior to the ejection operation performed using the print head 7 may be provided.

Further, in the inside of the main body of the printing apparatus 1, the distance between the print head 7 and the tray 4 when the print head 7 and the tray 4 are opposed to each other, and a medium is set on the tray 4. Includes a sensor 10 as a detection unit capable of detecting PG (see FIG. 5) which is a distance between the print head 7 and the medium. Specifically, the sensor 10 can detect whether PG is below a predetermined range (or below a predetermined range).
The sensor 10 is configured to detect whether or not an object (interfering substance) that interferes (can interfere with) the print head 7 exists on the tray 4 by measuring PG. . Here, the “interfering substance” means a foreign matter attached to the medium as well as wrinkles generated on the medium.
The sensor 10 is provided on an arch portion 12 that is movable along a rail 13 that extends along a facing direction C in which the print head 7 and the tray 4 face each other. Specifically, the sensor 10 includes a light emitting unit 10a and a light receiving unit 10b, and detects PG based on whether or not the light irradiated from the light emitting unit 10a toward the light receiving unit 10b can be detected by the light receiving unit 10b. It is a configuration. 2 and 3, the rail 13 on the light emitting unit 10a side is the rail 13a, and the rail 13 on the light receiving unit 10b side is the rail 13b.

As described above, the sensor 10 of the present embodiment is provided in the arch portion 12 that is movable along the facing direction C along the rail 13, and the arch portion 12 is moved along the facing direction C along the rail 13. It is the structure which can be made to do. However, the sensor 10 is not limited to such a configuration, and is not particularly limited as long as it is configured to be movable along the facing direction C. However, when using a detection unit composed of a plurality of components (such as the light emitting unit 10a and the light receiving unit 10b) like the sensor 10 of the present embodiment, the plurality of components are integrated as in the present embodiment. It is preferable that the configuration moves in a moving manner because it is possible to suppress a decrease in detection accuracy due to a shift in movement.
Details of the sensor 10 which is a main part of the printing apparatus 1 of the present embodiment will be described later.

Next, an electrical configuration of the printing apparatus 1 according to the present embodiment will be described.
FIG. 4 is a block diagram of the printing apparatus 1 according to the present embodiment.
The control unit 25 is provided with a CPU 26 that controls the entire printing apparatus 1. The CPU 26 is connected via a system bus 27 to a ROM 28 that stores various control programs executed by the CPU 26 and a RAM 29 that can temporarily store data.

The CPU 26 is connected to a head drive unit 30 for driving the print head 7 via a system bus 27.
In addition, the CPU 26 is connected to the motor drive unit 31 via the system bus 27. The motor drive unit 31 includes a carriage motor 32 for moving the carriage 6 provided with the print head 7 in the scanning direction B, and a conveyance motor for conveying the medium (for moving the tray 4 in the movement direction A). 33, connected to a sensor motor 34 for moving the arch portion 12 provided with the sensor 10.
Further, the CPU 26 is connected to the input / output unit 35 via the system bus 27. The input / output unit 35 is connected to the PC 36.

Next, the sensor 10 that is a main part of the printing apparatus 1 of the present embodiment will be described.
Here, FIGS. 5 to 8 are schematic side views showing the periphery of the formation region of the sensor 10 of the printing apparatus 1 of the present embodiment. Among these, FIG. 5 shows that the tray 4 is disposed at a desired position in the facing direction C and the sensor 10 is disposed at a desired position (PG detection position Pd) in the facing direction C, and the PG measurement is finished at the PG measurement end position. Represents the state of measuring. 6 assumes the use of a thick medium, and arranges the tray 4 at the lowest position in the facing direction C (position where PG is the widest), and places the sensor 10 in the desired position P1 in the facing direction C. This is a state in which the PG is measured at the PG measurement end position by being arranged at (PG detection position Pd). 7 assumes that a thin medium is used, and the tray 4 is disposed at the uppermost position in the facing direction C (the position where PG becomes the narrowest), and the sensor 10 is moved to a desired position P2 in the facing direction C ( A state is shown in which the PG is measured at the PG measurement end position by being arranged at the PG detection position Pd). Further, FIG. 8 shows that the tray 4 moves in the direction A2 from the state shown in FIG. 5, and the position of the tray 4 deviates from the PG detectable position in the movement direction A by the sensor 10 (PG measurement is completed). ) Represents a state in which the sensor 10 is retracted to the uppermost position in the facing direction C.
5 to 8, in order to make it easy to understand the position of the sensor 10, the medium set on the tray 4, the arch portion 12, and the like are omitted in addition to the casing portion of the printing apparatus 1. .
5 to 7, the position of the tray 4 and the position of the sensor 10 in the facing direction C correspond to each other in FIGS. 5 to 7, but the tray 4 and the sensor 10 move in the facing direction C in conjunction with each other. Instead of moving, each moves independently. For this reason, for example, when the medium swells, only the sensor 10 can be moved in the facing direction C without moving the tray 4 in the facing direction C.

As described above, the sensor 10 of the present embodiment is movable along the facing direction C along the rail 13. The printing apparatus 1 according to the present embodiment moves the tray 4 from the set position (see FIG. 3) in the direction A1, and reaches the PG measurement end position, which is the position of the tray 4 shown in FIGS. Move. Then, the tray 4 is moved in the direction A2 from the PG measurement end position, the tray is positioned in the ejection start position, and the printing operation (ink ejection process) is performed while moving the tray 4 in the direction A2. Here, while the tray 4 is moved from the set position to the PG measurement end position, the sensor 10 is located at the detection position Pd in the facing direction C, but the PG in the movement direction A by the sensor 10 during that time. While the tray 4 is positioned at the detectable position, the sensor 10 detects PG (PG detection step). As shown in FIGS. 5 to 7, when the tray 4 is removed from the PG detectable position in the movement direction A by the sensor 10 at the detection position Pd (moved to the PG measurement end position), the sensor 10 It moves to the retracted position Pe shown in FIG.
Further, as shown in FIGS. 5 to 7, in the PG detection process, the sensor 10 detects the PG from the position P1 to the position P2 in accordance with the thickness of the medium to be used and the expected degree of swelling of the medium. The detection position Pd can be changed.

  The PG detection position Pd is preferably closer to the print head 7 (specifically, the ink ejection area of the print head 7). This is because the configuration in which the PG detection position Pd is far from the print head 7 tends to increase the size of the apparatus, and the PG detection accuracy is likely to be lowered. For this reason, as shown in FIGS. 5 to 7, in the printing apparatus 1 of the present embodiment, the position where the sensor 10 is provided is in the vicinity of the print head 7. On the other hand, if the sensor 10 is in the vicinity of the print head 7 after the printing operation is started, ink mist tends to adhere to the sensor 10, and the PG detection accuracy by the sensor 10 may decrease. Therefore, in the printing apparatus 1 of the present embodiment, the sensor 10 is retracted from the vicinity of the print head 7 (moved to the retracted position Pe) before the start of the printing operation (after the end of PG measurement).

Here, once summarized, the printing apparatus 1 of the present embodiment includes a print head 7 that can eject ink, a tray 4 that supports a medium on which ink is ejected, and that can move along the moving direction A, and printing. And a sensor 10 that detects whether or not an interference object that is an object that interferes with the head 7 exists on the tray 4. The sensor 10 is configured to be movable in the facing direction C, which is the direction in which the tray 4 and the print head 7 face each other.
As shown in FIGS. 5 to 7, the printing apparatus 1 of this embodiment is configured so that the sensor 10 can move in the facing direction C. Therefore, even when the medium swells, the sensor 10 is moved in the facing direction C. By moving to, it is possible to detect whether or not an interference exists on the tray 4 with high accuracy.
The moving direction of the sensor 10 may be a direction inclined with respect to the facing direction C in addition to the direction along the facing direction C as in the printing apparatus 1 of the present embodiment. That is, the sensor 10 only needs to be configured so that the position in the facing direction C can be changed. “The sensor 10 can move in the facing direction C” means that the sensor 10 changes its position in the facing direction C. It is possible to move.

Further, the movement of the sensor 10 is performed by the control unit 25 controlling a sensor motor 34 that is a movement mechanism of the sensor 10, a ball screw (not shown), or the like.
Specifically, the control unit 25 inputs setting information, which is information set for an image formed on the medium by ejecting ink from the print head 7, and moves the sensor 10 based on the setting information (of the sensor 10. Control the moving mechanism.
For this reason, the printing apparatus 1 according to the present embodiment is configured to be able to predict the degree of swelling of the medium from the setting information, and to detect whether or not the interference exists on the support portion with high accuracy. ing.
In addition, the user can input setting information (information such as medium type) to the control unit 25 via the PC 36 or the like, and the control unit 25 can set setting information (from the image data to be used) (input from the PC 36). The amount of ink applied and the printing mode can also be determined.
Further, there is no limitation on the configuration of the “movement mechanism of the sensor 10”.

In other words, the print head 7 that can eject ink, the tray 4 that supports the medium from which ink is ejected, and that can move along the moving direction A, and the object that interferes with the print head 7 are shown. This is set for an image formed on a medium by ejecting ink from the print head 7 using the printing apparatus 1 of the present embodiment, which includes a sensor 10 that detects whether or not an interference exists on the tray 4. On the basis of the setting information that is the information to be detected, it is possible to execute an interference detection method that moves the sensor 10 in the facing direction C, which is the direction in which the tray 4 and the print head 7 face each other.
For this reason, by executing the detection method of the interference object, the degree of swelling of the medium can be predicted from the setting information, and it is possible to detect whether or not the interference object exists on the tray 4 with high accuracy. .

Here, the setting information includes medium type information.
For this reason, the printing apparatus 1 of the present embodiment predicts how much the swelling medium swells by determining whether the medium used is easily swelled or difficult to swell in the control unit 25. The sensor 10 can be moved, and it can be detected whether or not an interference exists on the tray 4 with particularly high accuracy.
The “medium type” is specifically a difference in, for example, the material of the medium, the basis weight (thickness) of the medium, the product name, and the like.

The setting information includes information on the amount of ink applied per unit area to the medium.
For this reason, the printing apparatus 1 of the present embodiment can move the sensor 10 after predicting how much the swelling medium swells in the control unit 25, and the interference is present on the tray 4 with particularly high accuracy. It is possible to detect whether or not.
Note that “the amount of liquid applied per unit area” means the amount of ink applied in each part of the medium when the amount of applied ink is not uniform when viewed in the unit area of the medium. It means the value of the maximum part.

Here, the printing apparatus 1 of the present embodiment forms an image forming layer with white ink for base printing, and then forms an image forming layer with color ink (black ink, cyan ink, magenta ink, yellow ink, etc.). It can be configured. Specifically, the tray 4 is moved in the direction A1 from the set position to the PG measurement end position (with a PG detection step), the tray 4 is moved in the direction A2 to the print start position, and the tray 4 is moved in the direction A2. Then, the image forming layer is formed with white ink, and then the tray 4 is moved in the direction A1 to the PG measurement end position (with a PG detection step), the tray 4 is moved in the direction A2 to the print start position, and the direction A2 The image forming layer is formed with color ink while moving the tray 4. That is, the printing apparatus 1 according to the present embodiment is configured to be able to form an image on a medium by superimposing a plurality of image forming layers including at least a layer formed using ink.
The setting information includes information on the number of layers constituting the image forming layer.
In a configuration in which an image can be formed on a medium by superimposing a plurality of image forming layers, the degree of swelling of the medium may change every time each layer is formed. However, in the printing apparatus 1 of the present embodiment, the setting information includes information on the number of layers constituting the image forming layer. Therefore, how much the swelling medium swells each time the layers are formed in the control unit 25. It is possible to detect whether or not an interference object exists on the tray 4 with a particularly high accuracy.
In the above, the first image formation layer formation (first discharge operation) is the discharge operation with white ink for base printing, and the second image formation layer formation (second discharge operation) is color. Although described as an ejection operation with ink, the image forming layer can be formed only by an ejection operation with color ink without using white ink. When the image forming layer is formed only by the color ink ejection operation, it can be completed by forming the image forming layer only once or can be formed a plurality of times. .

Further, to explain the above from another point of view, in the printing apparatus 1 of the present embodiment, the tray 4 is set along the moving direction A in the set position where the medium is set, and the ejection of ink by the print head 7 is started. It is possible to move between the discharge start position. Further, in the moving direction A, the print head 7 has an end on the set position side (not on the discharge start position side) of the tray 4 at the set position and the discharge start position side (set on the tray 4 at the discharge start position). Ink can be ejected onto the medium at a position between the end of the side that is not on the position side. Then, the control unit 25 can cause the tray 4 supporting the medium to move along the moving direction A and cause the ejection operation to eject ink from the print head 7 to the medium a plurality of times.
When the controller 25 performs the ejection operation a plurality of times, the position of the sensor 10 in the facing direction C during the second ejection operation is higher than the position in the facing direction C during the first ejection operation. Can be moved. In other words, the control unit 25 has a facing direction C between the sensor 10 and the tray 4 in the second ejection operation rather than a distance in the facing direction C between the sensor 10 and the tray 4 in the first ejection operation. The sensor 10 can be moved so that the distance becomes longer.
When the discharge operation is performed a plurality of times, the medium is more often swollen during the second discharge operation than during the first discharge operation, but the second discharge is performed compared to the first discharge operation. By moving the sensor 10 so that the distance in the facing direction C between the sensor 10 and the tray 4 is longer during operation, the medium is swollen more during the second discharge operation than during the first discharge operation. Even in such a case, it is possible to detect whether or not an interference exists on the tray 4 with particularly high accuracy.
In addition, as an example of “performing the ejection operation a plurality of times”, the ejection operation with the white ink for base printing and the ejection operation with the color ink are performed once, or the white ink for base printing. For example, the discharge operation with color ink may be performed a plurality of times without performing the discharge operation in the above, but there is no particular limitation.

  As described above, the printing apparatus 1 according to the present embodiment can perform the ejection operation a plurality of times (form an image on a medium by superimposing a plurality of image forming layers), but the PG changes with each ejection operation. In this case, the ink ejection timing from the print head 7 can be changed corresponding to PG under the control of the control unit 25. For this reason, the printing apparatus 1 of the present embodiment is configured to be able to reduce the deviation of the ink landing position on the medium due to the change of PG.

As shown in FIGS. 6 and 7, the printing apparatus 1 according to the present embodiment has the maximum tray 4 in the facing direction C even when the tray 4 is lowered to the maximum in the facing direction C (FIG. 6). Even in the case of the limit (FIG. 7), the sensor 10 can move to a position where PG can be detected. Further, as shown in FIG. 8, the sensor 10 can move to an upper position in the facing direction C from the position shown in FIG. 7. That is, in the printing apparatus 1 of the present embodiment, the movement range of the sensor 10 in the facing direction C includes PG that is the facing range of the tray 4 and the print head 7 in the facing direction C.
For this reason, the printing apparatus 1 according to the present embodiment has a high accuracy because the sensor 10 can move in accordance with the degree of swelling of the medium regardless of the range of the opposed range where the medium supported by the tray 4 swells. Thus, it is possible to detect whether or not an interference exists on the tray 4.
Note that “the facing range of the tray 4 and the print head 7 in the facing direction C” refers to a case where the tray 4 is movable in the facing direction C as in the printing apparatus 1 of this embodiment, or the print head 7. Is configured to be movable in the facing direction C, the entire range when the facing range (PG) is the largest is assumed.

  In addition, this invention is not limited to the said Example, A various deformation | transformation is possible within the range of the invention described in the claim, and it cannot be overemphasized that they are also contained in the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 ... Printing apparatus (liquid discharge apparatus), 2 ... Medium support unit, 3 ... Medium conveyance part,
4 ... tray (supporting part), 5 ... stage, 6 ... carriage, 7 ... print head (ejection part),
8 ... support surface, 9 ... lever, 10 ... sensor (detection unit), 10a ... light emitting unit,
10b ... light receiving part, 11 ... arm part, 12 ... arch part, 13 ... rail,
13a ... rail, 13b ... rail, 25 ... control unit, 26 ... CPU,
27 ... System bus, 28 ... ROM, 29 ... RAM, 30 ... Head drive unit,
31 ... Motor drive unit, 32 ... Carriage motor, 33 ... Conveyance motor,
34 ... sensor motor, 35 ... input / output unit, 36 ... PC,
P1: a desired position in the facing direction C, P2: a desired position in the facing direction C,
Pd: detection position of PG, Pe: retraction position,
PG: The distance between the print head 7 and the tray 4 when the print head 7 and the tray 4 are in a facing position.

Claims (8)

A discharge part capable of discharging liquid;
A support unit that supports the medium from which the liquid is discharged and is movable along the movement direction;
A detection unit that detects whether or not an interference object that is an object that interferes with the discharge unit exists on the support unit,
The liquid ejecting apparatus according to claim 1, wherein the detection unit is configured to be movable in an opposing direction, which is a direction in which the support unit and the ejection unit are opposed to each other. The liquid ejection apparatus according to claim 1,
A liquid ejection apparatus comprising: a control unit that controls movement of the detection unit based on setting information that is set with respect to an image formed on the medium by ejecting the liquid from the ejection unit. The liquid ejection apparatus according to claim 2, wherein
The liquid ejection apparatus, wherein the setting information includes information on a type of the medium. The liquid ejection device according to claim 2 or 3,
The liquid ejecting apparatus according to claim 1, wherein the setting information includes information on an application amount of the liquid per unit area with respect to the medium. The liquid discharge apparatus according to any one of claims 2 to 4,
A plurality of image forming layers including at least a layer formed using the liquid are stacked to form the image on the medium;
The liquid ejection apparatus, wherein the setting information includes information on the number of layers constituting the image forming layer. In the liquid ejection device according to any one of claims 2 to 5,
The support unit is movable along the moving direction between a set position where the medium is set and a discharge start position where the discharge of the liquid by the discharge unit is started,
In the movement direction, the discharge unit is located between an end portion on the set position side of the support portion at the set position and an end portion on the discharge start position side of the support portion at the discharge start position. The liquid can be discharged to the medium at a position of
The controller is
It is possible to perform a discharge operation of discharging the liquid from the discharge unit to the medium by moving the support unit supporting the medium from the discharge start position toward the set position side along the movement direction.
When the discharge operation is performed a plurality of times, the distance between the detection unit and the support unit in the second discharge operation is larger than the distance in the facing direction between the detection unit and the support unit in the first discharge operation. The liquid ejecting apparatus, wherein the detection unit is moved so that a distance in the facing direction is longer. The liquid ejection apparatus according to any one of claims 1 to 6,
The liquid ejecting apparatus according to claim 1, wherein the moving range of the detecting unit in the facing direction includes a facing range of the supporting unit and the ejecting unit in the facing direction. A discharge part capable of discharging liquid;
A support unit that supports the medium from which the liquid is discharged and is movable along the movement direction;
A detecting unit that detects whether or not an interfering object that is an object that interferes with the discharging unit exists on the support unit, and a method for detecting an interfering substance with respect to the discharging unit in a liquid discharging apparatus comprising:
Based on setting information, which is information set on an image formed on the medium by discharging the liquid from the discharge unit, the detection unit is set in a facing direction, which is a direction in which the support unit and the discharge unit face each other. A method for detecting an interfering object, characterized by being moved.

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