JP6627476B2 - Liquid ejection device, liquid ejection method, and program - Google Patents

Description

  The present invention relates to a liquid ejection device, a liquid ejection method, and a program.

  2. Description of the Related Art There is known a printer device that forms an image by discharging ink or the like at the timing when the sheet is conveyed and reaches the image forming position. On the other hand, printers (hereinafter, referred to as HHPs: handheld printers) that have been downsized by removing the paper transport system from the printers are being put to practical use.

  FIG. 1 is an example of a diagram schematically illustrating image formation by the HHP 20. Image data is transmitted to the HHP 20 from an image data output device such as a smartphone or a PC (Personal Computer). The user grips the HHP 20 placed on the recording medium 12 (for example, a fixed form paper or a notebook) and scans the surface of the recording medium 12 freehand. Since the HHP 20 has a position detecting mechanism, when the HHP 20 moves to the target ejection position, the HHP 20 ejects ink of the color to be ejected at the target ejection position. In FIG. 1, when the user moves the HHP 20 substantially along the dotted line 101, an image 102 is formed as shown. Since the place where ink has already been ejected is masked (since it is not a target of ink ejection), the user can form an image by scanning the HHP 20 on the recording medium 12 in an arbitrary direction.

  In the HHP 20, correspondence between each nozzle 61 of the recording head provided in the main body and an image to be printed first (specifically, pixels in the image 102) is set in advance. The direction of the HHP 20 and the direction of the image are also set in advance. In FIG. 1, the relative position of the image data with respect to the HHP 20 is set by associating the top nozzle of the recording head with the upper left corner of the image.

  Therefore, it is necessary for the user to arrange the HHP 20 so that the nozzles 61 are arranged vertically at the upper left of the recording medium 12 and start image formation. In the conventional HHP 20, the user can freely change the orientation of the HHP 20 with respect to the recording medium 12. There is a restriction that you can not.

  FIG. 2 is an example of a diagram for explaining the restriction on the orientation of the main body with respect to the recording medium 12. The arrow A shown on the HHP 20 indicates the head direction of the nozzle 61. When the relative position between the HHP 20 and the image data is set by associating the arrangement direction of the nozzles 61 with the vertical direction of the image, the user places the HHP 20 on the recording medium 12 as shown in FIG. By doing so, the HHP 20 can form the image 102 on the recording medium 12.

  However, as shown in FIG. 2B, when the user arranges the HHP 20 so that the arrangement direction of the nozzles of the HHP 20 is parallel to the horizontal direction of the recording medium 12, the image 102 protrudes from the recording medium 12.

  There is a possibility that such restrictions can be dealt with by using the absolute position of the HHP 20 with respect to the recording medium 12. Conventionally, a technology for detecting the absolute position of the HHP 20 with respect to the recording medium 12 has been devised (for example, see Patent Document 1). Patent Document 1 discloses a method of calibrating the position of the HHP 20 in which a tagging pattern in which absolute position information is embedded is formed on a print medium, and the pattern is read by a sensor to detect the absolute position of the HHP 20.

  However, detecting the absolute position of the HHP 20 by the method disclosed in Patent Literature 1 requires a function for a tagging pattern and an image sensor, so that there is a problem that the size and cost of the main body are increased. .

  The present invention has been made in view of the above circumstances, and has as its object to provide a liquid ejection apparatus in which restrictions on the orientation with respect to a recording medium are reduced.

In view of the above problems, the present invention is a liquid ejecting apparatus that forms an image while moving on a recording medium, and a position detecting unit that detects a position on the recording medium, and detects a moving direction of the liquid ejecting apparatus. Moving direction detecting means, direction estimating means for estimating the direction of the liquid ejecting apparatus with respect to the recording medium in accordance with the moving direction detected by the moving direction detecting means, and the position of the liquid ejecting apparatus. Determining means for determining whether or not the moving distance in the moving direction is greater than a certain distance; and the direction estimating means when the determining means determines that the moving distance in the moving direction is larger than a certain distance. and position setting means for setting the discharge position on the recording medium depending on the orientation of the liquid ejection device for estimated the recording medium, the discharge position set by said position setting means Having an image forming means for forming on said recording medium an image corresponding to.

  It is possible to provide a liquid ejection apparatus in which the restriction on the orientation with respect to the recording medium is reduced.

FIG. 2 is an example of a diagram schematically showing image formation by HHP. FIG. 4 is an example of a diagram for explaining a restriction on an orientation of a main body with respect to a recording medium. FIG. 3 is an example of a diagram for explaining an outline of a method for detecting an orientation of a handheld printer with respect to a recording medium. FIG. 2 is an example of a hardware configuration diagram of the HHP. FIG. 3 is a diagram illustrating an example of a functional block diagram of a control unit. It is an example of a figure explaining the position etc. of the nozzle of HHP. It is an example of a figure explaining calculation of the position of HHP. It is an example of a figure explaining the moving direction of HHP. FIG. 4 is an example of a diagram for explaining association between nozzles and image data. FIG. 7 is an example of a flowchart illustrating a procedure for detecting the orientation of the HHP with respect to a recording medium and setting a relative position of image data with respect to a nozzle. FIG. 8 is a diagram illustrating an example of a functional block diagram of a control unit (second embodiment). FIG. 14 is an example of a flowchart illustrating a procedure for detecting the orientation of the HHP with respect to the recording medium and setting the relative position of the image data with respect to the nozzles (second embodiment). FIG. 13 is a diagram illustrating an example of a functional block diagram of a control unit (third embodiment). FIG. 14 is an example of a flowchart illustrating a procedure for detecting the orientation of the HHP with respect to the recording medium and setting the relative position of the image data with respect to the nozzles (third embodiment). It is an example of a figure for explaining a human sensor arranged in HHP. FIG. 14 is an example of a hardware configuration diagram of an HHP (fourth embodiment). FIG. 14 is a diagram illustrating an example of a functional block diagram of a control unit (Example 4). FIG. 14 is an example of a flowchart illustrating a procedure for detecting the orientation of the HHP with respect to the recording medium and setting the relative position of the image data with respect to the nozzles (Embodiment 4). FIG. 4 is an example of a diagram for explaining association between nozzles and image data. FIG. 14 is a diagram illustrating an example of a functional block diagram of a control unit (Embodiment 5). FIG. 4 is a diagram illustrating an example of an arrangement when HHP is arranged on a recording medium. FIG. 13 is an example of a flowchart illustrating a procedure for detecting the orientation of the HHP with respect to the recording medium and setting the relative position of the image data with respect to the nozzles (Embodiment 5).

  Hereinafter, embodiments for carrying out the present invention will be described with reference to the drawings.

<Outline of operation of handheld printer>
FIG. 3 is an example of a diagram illustrating an outline of a method for detecting the orientation of the handheld printer with respect to the recording medium. As shown in FIG. 3A, a handheld printer (hereinafter, referred to as HHP) has a function of detecting a moving direction. Hereinafter, the function of detecting the moving direction is referred to as moving direction detecting means 103. Arrow A indicates the head direction of nozzle 61. This moving direction detecting means 103
Moving to the left side (assuming the direction of the first nozzle to be vertically upward and the left side of the direction perpendicular to the arrangement direction of the nozzles 61)
Moving to the right (assuming the direction of the first nozzle to be vertically upward, and the right side of the direction perpendicular to the arrangement direction of the nozzles 61)
Is detected.

  In FIG. 3B, the HHPs 20 are arranged such that the arrangement direction of the nozzles 61 is parallel to the longitudinal direction of the recording medium 12. In this case, at the start of image formation, the user moves the HHP 20 to the right to start image formation. Since the moving direction detecting means 103 detects the rightward movement, it can be estimated that the HHP 20 is arranged parallel to the longitudinal direction of the recording medium 12.

  In FIG. 3C, the HHPs 20 are arranged such that the arrangement direction of the nozzles 61 of the HHPs 20 is parallel to the horizontal direction of the recording medium 12. In this case, at the start of image formation, the user moves the HHP 20 to the left to start image formation. Since the movement direction detecting means 103 detects the movement to the left, it can be estimated that the HHP 20 is arranged parallel to the recording medium 12 in the horizontal direction.

  Then, the HHP 20 associates an image to be formed first with the nozzle 61 in accordance with the detected orientation of the HHP 20 with respect to the recording medium 12. For example, it is assumed that the arrangement of the HHP 20 in FIG. Therefore, in the case of FIG. 3B, the HHP 20 keeps the correspondence between the nozzle and the image as the standard. On the other hand, when it is estimated that the HHP 20 is arranged parallel to the horizontal direction of the recording medium 12, the HHP 20 changes the relative position of the image data with respect to the HHP 20, which is its own device, from the standard state. Specifically, the ejection position on the recording medium is set by associating the head of the nozzle 61 with the upper left corner of the image data, and associating the nozzles after the head nozzle with the image on the upper side of the image data.

  With the above-described processing, the restriction on the orientation of the HHP 20 with respect to the recording medium 12 can be reduced.

  The arrangement shown in FIG. 3A is referred to as “the HHP 20 is vertically oriented with respect to the recording medium 12”, and the arrangement shown in FIG. There is ". Setting an ejection position on the recording medium 12 means associating each nozzle 61 with image data.

<Configuration example>
FIG. 4 shows an example of a hardware configuration diagram of the HHP 20. The HHP 20 is an example of a liquid ejection apparatus or an image forming apparatus that forms an image on the recording medium 12. A liquid discharge device is a device that discharges droplets of ink or the like at the timing when the liquid reaches a droplet discharge position. When the ink forms an image, it is called an image forming device.

  The entire operation of the HHP 20 is controlled by a control unit 25, and a communication I / F 27, an IJ recording head drive circuit 23, an OPU 26, a ROM 28, a DRAM 29, and a navigation sensor 30 are electrically connected to the control unit 25. . Further, since the HHP 20 is driven by electric power, it has a power supply 22 and a power supply circuit 21. The power generated by the power supply circuit 21 is transmitted to the communication I / F 27, the IJ recording head drive circuit 23, the OPU 26, the ROM 28, the DRAM 29, the IJ recording head 24, the control unit 25, and the navigation sensor 30 by wiring indicated by a dotted line 22a. Supplied.

  As the power supply 22, a battery (battery) is mainly used. A solar cell, a commercial power supply (AC power supply), a fuel cell, or the like may be used. The power supply circuit 21 distributes the power supplied by the power supply 22 to each unit of the HHP 20. In addition, the voltage of the power supply 22 is stepped down or stepped up to a voltage suitable for each unit. When the power supply 22 can be charged by a battery, the power supply circuit 21 detects the connection of the AC power supply and connects the AC power supply to a battery charging circuit to enable the power supply 22 to be charged.

  The communication I / F 27 receives image data from an image data output device such as a smartphone or a PC (Personal Computer). The communication I / F 27 is a communication device that supports communication standards such as wireless LAN, Bluetooth (registered trademark), NFC (Near Field Communication), infrared, 3G (mobile phone), and LTE (Long Term Evolution). In addition, other than such wireless communication, a communication device that supports wired communication using a wired LAN, a USB cable, or the like may be used.

  The ROM 28 stores firmware for controlling hardware of the HHP 20, driving waveform data of the IJ recording head 24 (data defining a voltage change for ejecting liquid droplets), initial setting data of the HHP 20, and the like.

  The DRAM 29 is used for storing image data received by the communication I / F 27 and for storing firmware developed from the ROM 28. Therefore, it is used as a work memory when the CPU of the control unit 25 executes the firmware.

The navigation sensor 30 is a sensor that detects the position of the HHP 20. The navigation sensor 30 includes, for example, a light source such as a light emitting diode (LED) or a laser, and an image sensor that images the recording medium 12. When the HHP 20 is scanned over the recording medium 12, minute edges of the recording medium 12 are successively detected (imaged), and the movement amount is obtained by analyzing the distance between the edges. The navigation sensors 30 are mounted at at least two places on the HHP 20. When distinguishing them, they are called navigation sensors S ₀ and S ₁ . Note that a multi-axis acceleration sensor, a gyro sensor, or the like may be further used as the navigation sensor 30, and the position of the HHP 20 may be detected only by the acceleration sensor or the gyro sensor.

  The OPU (Operation panel Unit) 26 has LEDs for displaying the state of the HHP 20, switches for the user to instruct the HHP 20 to perform image formation, and the like. However, the invention is not limited to this, and may have a liquid crystal display and may further have a touch panel. Further, it may have a voice input function.

  The IJ print head drive circuit 23 generates a drive waveform (voltage) for driving the IJ print head 24 using the above-described drive waveform data. A drive waveform according to the size of the ink droplet can be generated.

  The IJ recording head 24 is a head for discharging ink. In the figure, four colors of CMYK can be ejected, but a single color or five or more colors may be ejected. A plurality of ink discharge nozzles 61 are arranged in one line (or two or more lines) for each color. The ink ejection method may be a piezo method, a thermal method, or another method.

  The control unit 25 determines the position of each nozzle of the IJ recording head 24, determines an image to be formed according to the position, controls ink ejection, and the like, based on the movement amount detected by the navigation sensor 30. The control unit 25 includes a CPU that controls the entire control unit 25, an image RAM for buffering image data, a DMAC (Direct Memory Access Controller), an interrupt controller, and an interface with each peripheral circuit shown in FIG. It is an information processing device having. Details of the control unit 25 will be described below.

<< Control unit functions >>
Next, the functions of the control unit 25 will be described with reference to FIG. FIG. 5 is a diagram illustrating an example of a functional block diagram of the control unit 25. The control unit 25 includes a position calculation unit 31, an orientation detection unit 32, an image processing unit 33, an image position correspondence unit 34, and a recording head control unit 35. Each of these functional units is a function or means realized by executing a program stored in the ROM 28 by the CPU of the control unit 25 and controlling any of the components included in the control unit 25. Note that part or all of these functional units may be realized by hardware (such as an IC circuit).

  The position calculator 31 calculates the position of the HHP 20 on the recording medium based on the amount of movement for each sampling period detected by the navigation sensor 30. Although the position of the HHP 20 is strictly the position of the nozzle 61, if the position of the navigation sensor 30 is known, the position of the nozzle 61 can be calculated.

  The position of the navigation sensor 30 is calculated based on a predetermined origin (for example, the initial position of the HHP 20 when image formation is started) as described later.

  Further, the position calculation unit 31 includes a movement direction detection unit 31a. The moving direction detecting unit 31a estimates the moving speed and the moving direction based on the difference between the past position and the newest position, and predicts the position at the next calculation timing, for example. By doing so, it is possible to discharge ink while suppressing a delay with respect to scanning by the user.

  Therefore, in the present embodiment, the moving direction detecting section 31a corresponds to the moving direction detecting means 103. The position calculation unit 31 acquires from the OPU 26 that the user has input an image forming start operation to the OPU 26. Immediately after this, the movement direction detection unit 31a detects the direction in which the user has moved the HHP 20.

  The direction detection unit 32 detects the direction of the HHP 20 with respect to the recording medium 12 based on the movement direction detected by the movement direction detection unit 31a. Details will be described later.

  The image position corresponding unit 34 sets the relative position of the image data with respect to the nozzle 61 (HHP 20) of the IJ recording head 24 when the orientation detection unit 32 detects that the HHP 20 is in the horizontal direction with respect to the recording medium 12. Details will be described later.

  The image processing unit 33 rotates the image data stored in the DRAM 29 in accordance with the IJ recording head 24 for ejecting ink, the nozzle position in the head, and the inclination of the IJ recording head 24 due to a mounting error or the like. Further, the image processing unit 33 acquires the rotation angle θ of the HHP 20 in the horizontal direction on the recording medium 12 calculated when the position calculation unit 31 calculates the position, and rotates the peripheral image using the rotation angle θ. be able to.

  The recording head control unit 35 performs dither processing or the like on the image data (bitmap data) and converts the image data into a set of points representing the image in size and density. As a result, the image data becomes data of the ejection position and the dot size. The printhead control unit 35 outputs a control signal corresponding to the dot size to the IJ printhead drive circuit 23. The IJ recording head drive circuit 23 generates a drive waveform (voltage) using the drive waveform data corresponding to the control signal as described above.

<About the position of the HHP on the recording medium>
Next, nozzle positions and the like in the IJ recording head 24 will be described with reference to FIG. FIG. 6A is an example of a plan view of the HHP 20. FIG. 6B is an example of a diagram illustrating only the IJ recording head 24. The illustrated surface is the surface facing the recording medium 12.

The HHP 20 according to the present embodiment has two or more navigation sensors 30. Since there are two or more navigation sensors 30, even if the navigation sensor 30 rotates with respect to the recording medium 12 during image formation, the rotation angle θ can be detected. In FIG. 6A, two navigation sensors S ₀ and S ₁ are arranged apart from each other in the arrangement direction of the nozzles 61. The length between the two navigation sensors S ₀ and S ₁ is a distance L. The longer the distance L, the better. This is because the longer the distance L is, the smaller the minimum detectable rotation angle θ is, and the error in the position of the HHP 20 is reduced.

  The distances from the navigation sensor 30 to the IJ recording head 24 are distances a and b, respectively. The distance a and the distance b may be equal. As shown in FIG. 6B, the distance from the end of the IJ recording head 24 to the first nozzle 61 is a distance d, and the distance between adjacent nozzles is a distance e. The values of a to e are stored in advance in the ROM 28 or the like.

  Therefore, if the position calculation unit 31 or the like calculates the position of the navigation sensor 30, the position calculation unit 31 can calculate the position of the nozzle 61 using the distance a, the distance b, the distance d, and the distance e.

In the present embodiment, the direction parallel to the recording medium 12 is set to the X axis, and the direction perpendicular to the recording medium 12 is set to the Y axis. These coordinates will be referred to as recording medium coordinates. On the other hand, the navigation sensor 30 outputs a position on the following coordinate axes (X ′ axis, Y ′ axis). That is, the arrangement direction of the nozzles 61 (the direction connecting the two navigation sensors S ₀ and S ₁ ) is defined as the Y ′ axis, and the direction orthogonal to the Y ′ axis is defined as the X ′ axis.

Next, the position of the HHP 20 will be described with reference to FIG. In FIG. 7A, the HHP 20 rotates clockwise θ with respect to the recording medium 12. If there is no rotation, X = X 'and Y = Y'. However, when the HHP 20 rotates by the rotation angle θ with respect to the recording medium 12, the outputs of the navigation sensors S ₀ and S ₁ do not match the actual position of the HHP 20 on the recording medium 12.

Therefore, as shown in FIG. 7A, ΔX ′ and ΔY ′ output from the navigation sensors S ₀ and S ₁ correspond to X and Y of the recording medium coordinates as follows. In FIG. 7A, the movement amounts ΔX ′, ΔY detected by the navigation sensors S ₀ , S ₁ (the outputs are equal because they are parallel movements) when the HHP 20 having the rotation angle θ moves at the same rotation angle θ only in the X direction. 'And the correspondence between X and Y. ΔX ′ output from the navigation sensors S ₀ and S ₁ is reflected on X1, and ΔY ′ is reflected on X2.

In FIG. 7B, the movement amounts ΔX ′ and ΔY detected by the navigation sensors S ₀ and S ₁ (the outputs are equal because they are parallel movements) when the HHP 20 having the rotation angle θ moves in the Y direction with the same rotation angle θ. 'And the correspondence between X and Y. ΔY ′ output from the navigation sensors S ₀ and S ₁ is reflected on Y1, and −ΔX ′ is reflected on Y2.

Therefore, when the HHP 20 moves with the rotation angle θ in the X direction and the Y direction, ΔX ′ and ΔY ′ output by the navigation sensors S ₀ and S ₁ can be converted into X and Y of the recording medium coordinates as follows.
X = ΔX′cosθ + ΔY′sinθ (1)
Y = −ΔX′sinθ + ΔY′cosθ (2)
In this way, if the rotation angle θ is known from the start position of the image formation, the positions of the coordinates of the recording medium of the navigation sensors S ₀ and S ₁ can be obtained from the equations (1) and (2). The image formation start position is a position where the user presses a button or the like of the HHP 20 to start image formation or a position where ink ejection is started. Generally, the start position of image formation is slightly inside the upper left corner of the recording medium 12.

The rotation angle dθ during the sampling times ΔX ′ and ΔY ′ can be obtained as follows from the difference between the outputs (ΔX ′ ₀ and ΔX ′ ₁ ) of the two navigation sensors S ₀ and S ₁ .
dθ = arcsin ｛(ΔX ′ ₀ −ΔX ′ ₁ ) / L｝ (3)
The position calculation unit 31 calculates the position in the X direction by Expression (1). In the coordinate system of FIG. 7A, if X is positive, it has moved to the right, and if X is negative, it has moved to the left. Can be detected by the moving direction detection unit 31a. Therefore, the moving direction of the HHP 20 can be detected based on whether the value of X immediately after the user inputs the image forming start operation to the OPU 26 is positive or negative.

<Moving direction of HHP>
FIG. 8A is an example of a diagram for explaining a moving direction of the HHP 20. As described above, the left side is defined as the left side of the HHP 20 in the top view of the HHP 20 (the direction of the leading nozzle 61s is vertically upward), and the right side is defined as the right side of the HHP 20 in the top view of the HHP 20. Marks 104 for specifying right and left may be attached or formed so that the user can grasp the direction. Alternatively, a shape such that the right or left can be recognized by touch may be formed on at least one of the left side surface and the right side surface of the HHP 20.

  When the HHP 20 is disposed vertically with respect to the recording medium 12 as shown in FIG. 8B, immediately after the image forming start operation, the user causes the HHP 20 to scan rightward, and then performs reciprocation in the left-right direction. The image is repeatedly formed on the recording medium 12. Therefore, in the present embodiment, when the HHP 20 moves rightward immediately after the start operation of the image formation, the direction detection unit 32 estimates that the HHP 20 is vertically oriented with respect to the recording medium 12.

  Similarly, when the HHP 20 is disposed vertically with respect to the recording medium 12 as shown in FIG. 8C, immediately after the image forming start operation, the user scans the HHP 20 to the left, and then moves in the left and right direction. (The vertical direction in the figure) is repeated to form an image on the recording medium 12. Therefore, in this embodiment, when the HHP 20 moves to the left immediately after the image forming start operation, the direction detection unit 32 estimates that the HHP 20 is in the horizontal direction with respect to the recording medium 12.

  Note that the estimation of the moving direction of the HHP 20 and the direction of the HHP 20 with respect to the recording medium 12 may be reversed. At the start of image formation, if the HHP 20 is vertically arranged, for example, at the upper right corner of the recording medium 12, the user scans to the left. Therefore, in this case, the direction of the HHP 20 with respect to the recording medium 12 is the vertical direction. In addition, at the start of image formation, if the HHP 20 is arranged horizontally, for example, at the lower left corner of the recording medium 12, the user scans to the right. Therefore, in this case, the direction of the HHP 20 with respect to the recording medium 12 is horizontal.

  Further, since the moving direction and the direction of the HHP 20 correspond one-to-one, the direction of the HHP 20 with respect to the recording medium 12 does not need to be determined. In the present embodiment, the direction detection unit 32 is specified for the sake of explanation, but the relative position of the image data with respect to the HHP 20 may be set based on the moving direction.

<Setting of relative position of image data with respect to HHP 20>
The correspondence between the nozzle 61 and the image data will be described with reference to FIG. FIG. 9A illustrates the correspondence between the nozzles 61 and the image data 105 when the HHP 20 is oriented vertically with respect to the recording medium 12. The HHP 20 sets the relative position of the image data 105 with respect to the HHP 20 before starting the image formation. In the present embodiment, the relative position of the image data 105 with respect to the HHP 20 is set in advance assuming that the state in which the HHP 20 is vertically oriented with respect to the recording medium 12 is the standard state. Since FIG. 9A is in the standard state, the image position corresponding unit 34 does not change the relative position of the image data with respect to the HHP 20. Therefore, the leading nozzle 61s is kept associated with the origin at the upper left of the image data, and the leading nozzles 61 are kept associated with the image on the left side of the image data corresponding to the position of the nozzle.

  FIG. 9B is a diagram for explaining the correspondence between the nozzles 61 and the image data 105 when the HHP 20 is oriented sideways with respect to the recording medium 12. The first nozzle 61s is associated with the origin at the upper left of the image data 105, and the nozzles 61 after the first are associated with the image on the left side of the image data 105. On the other hand, the HHP 20 is lateral to the recording medium 12. Therefore, the image data 105 protrudes from the recording medium 12 at the relative position of the image data 105 with respect to the HHP 20 in the standard state.

  Therefore, as shown in FIG. 9C, the image position corresponding unit 34 changes the relative position of the image data with respect to the HHP 20. Specifically, the head nozzle 61s is associated with the origin at the upper left of the image data 105, and the nozzles 61 after the head are associated with the upper image of the image data 105 corresponding to the position of the nozzle 61. By doing so, the ejection position of the HHP 20 on the recording medium 12 can be set. More specifically, the relative position between the HHP 20 and the image data is obtained so that the image data 105 is arranged in the range scanned by the HHP 20. The HHP 20 forms (discharges) an image (pixel) corresponding to the position of the nozzle 61 in the image data 105 for which the relative position is set, on the recording medium 12. Therefore, the HHP 20 can form image data on the recording medium 12.

(Change of coordinates on recording medium 12)
Although the HHP 20 calculates X and Y based on the arrangement direction of the nozzles 61 as shown in FIG. 7, the coordinates of the image data 105 remain unchanged (the horizontal direction of the recording medium is the X axis, The direction is Y axis). For this reason, when the HHP 20 is in the horizontal direction, the position calculator 31 changes the method of calculating X and Y.
Movement amount of HHP 20 with respect to recording medium 12 in the right direction = −Y
Movement amount of HHP 20 to recording medium 12 in the left direction = Y
The amount of downward movement of the HHP 20 with respect to the recording medium 12 = -X
The amount of upward movement of the HHP 20 with respect to the recording medium 12 = X
Thus, even after the association between the nozzle 61 and the image data is changed, consistency with the coordinates of the image data 105 can be obtained.

<Operation procedure>
FIG. 10A is an example of a flowchart illustrating a procedure for detecting the orientation of the HHP 20 with respect to the recording medium 12 and setting the relative position of the image data with respect to the nozzle 61. The procedure in FIG. 10A starts when information such as image data is received and preparation for image formation is completed.

  The position calculation unit 31 determines whether a trigger for starting image formation has been detected (S10). The trigger for starting the image formation is input from the OPU 26 (user operation), but is not limited to this. For example, when the movement direction detection unit 31a detects the movement of the HHP 20, or when a certain time has elapsed after receiving the image data 105 from an image data output device such as a smartphone or a PC (Personal Computer), the trigger of the start of image formation is triggered. You may judge that it was detected.

  If Yes is determined in step S10, it is determined whether the position calculation unit 31 has detected that the HHP 20 has moved (S20). This movement includes a direction other than the right side or the left side.

  If the determination is Yes in step S20, the direction detection unit 32 determines whether the movement is to the right or to the left (S30). Even when the movement direction detecting unit 31a detects the movement of the HHP 20, the movement in a direction other than the right side or the left side is ignored. For example, when the recording medium 12 is moved only in the vertical direction (the arrangement direction of the nozzles 61), it is determined that the recording medium 12 has not been moved. When the recording medium 12 is moved obliquely with respect to the recording medium 12, since there is either the left component or the right component, the determination in step S30 is Yes. If the movement to either the left or right is not detected (directly below, directly above, when lifting has occurred, etc.), the process returns to step S20, and the presence or absence of the movement is determined again.

  If it is determined in step S30 that the movement is to the left, the orientation detection unit 32 estimates that the orientation is horizontal, and the image position correspondence unit 34 changes the correspondence between the nozzle 61 and the image data (S40).

  If it is determined in step S30 that the movement is to the right, the direction detection unit 32 estimates that the direction is vertical (S50). Since the association does not need to be changed when moving to the right side, the process ends.

  After step S40 and step S50, the HHP 20 starts image formation for actually ejecting ink. The estimated orientation of the HHP 20 may be displayed on the OPU 26 or the like, and image formation may be started after input from the user.

  As described above, according to the HHP 20 of the present embodiment, the direction of the HHP 20 is detected based on the moving direction, and the relative position of the image data with respect to the HHP 20 is changed. The restriction on the orientation of the HHP 20 can be reduced. The direction of the HHP 20 with respect to the recording medium 12 can be detected by the information processing time from the moment when the user moves to the time when the HHP 20 detects the movement. This information processing time is determined depending on the performance of the navigation sensor 30 and the control unit 25, but since it is a very short time, the discharge can be started to the extent that the user does not feel uncomfortable.

<Modification>
In the process of FIG. 10A, the position where the trigger of the image formation is detected in step S10 of FIG. 10A is different from the position where the ejection is actually started (after the detection of the trigger of the image formation is started). There is a time lag until the orientation is detected), and the position calculation of the HHP 20 may be started at the time when the trigger of the image formation start is detected in step S20. A flowchart in this case is as shown in FIG.

  That is, when it is determined as Yes in step S10, the position calculation unit 31 starts the position calculation (S12). Therefore, the position where the trigger for starting the image formation is detected can be set as the origin of the image data 105 (for example, the upper left corner). Accordingly, it is possible to suppress a shift in the start position of the image formation intended by the user.

  In the first embodiment, when the user intentionally moves the HHP 20, the orientation of the HHP 20 with respect to the recording medium 12 can be detected. However, if the HHP 20 moves in a direction opposite to the intended direction due to slight vibration or shaking or a malfunction of the user, an image may be formed in a direction not intended by the user. Therefore, in the present embodiment, a description will be given of the HHP 20 that estimates the direction when a movement of a certain distance is detected so that the direction of the HHP 20 is not estimated by a slight movement not intended by the user.

  FIG. 11 is a diagram illustrating an example of a functional block diagram of the control unit 25. In FIG. 11, components denoted by the same reference numerals in FIG. 5 perform the same function, and thus only the main components of the present embodiment will be described in some cases. The control unit 25 in FIG. 11 includes a determination unit 36. The determination unit 36 determines whether or not the amount of movement in the X direction detected by the movement direction detection unit 31a has exceeded a certain distance. The fixed distance is stored in the ROM 28. Alternatively, it may be set by the user from the OPU 26 and stored in the DRAM 29.

  FIG. 12 is an example of a flowchart illustrating a procedure for detecting the orientation of the HHP 20 with respect to the recording medium 12 and setting the relative position of the image data with respect to the nozzle 61. In the description of FIG. 12, differences from FIG. 10A will be mainly described.

  If it is determined in step S30 that the user has moved to the left, the determination unit 36 determines whether the user has moved to the left more than a certain distance (S32). Assuming that the right side of X obtained by Expression (1) is positive, it is determined whether or not the absolute value of X, which is a negative value, has become larger than a certain distance.

  Note that whether or not the user has moved beyond a certain distance is determined based on the total moving distance. That is, the determination unit 36 measures the movement distance by setting the time point at which the movement is detected in step S20 to zero. Therefore, the operation may be stopped halfway. For example, if the fixed distance is 20 cm, the user moves 10 cm to the left and 15 cm to the right, and the total moving distance is 5 cm to the right.

  Until the determination in step S32 becomes Yes, the process returns to step S20, and is performed again from the detection of the movement.

  If the determination in step S32 is Yes, the direction detection unit 32 estimates that the HHP 20 is in the vertical direction, as in the first embodiment, and changes the association between the nozzle 61 and the image data (S40).

  If it is determined in step S30 that it has moved to the right, the determination unit 36 determines whether it has moved to the right more than a certain distance (S34). Assuming that the value of X obtained by Expression (1) is positive on the right side, it is determined whether or not the positive value X has become larger than a certain distance. The fixed distances in steps S32 and S34 may be the same or different. Since the constant distance appropriate for the user is considered to be different depending on the shape and the moving direction of the recording medium 12, the optimal constant distance can be set by the difference between the constant distances in steps S32 and S34.

  The process returns to step S20 until the determination in step S34 becomes Yes, and the processing is performed again from the detection of the movement.

  If the determination in step S34 is Yes, the orientation detection unit 32 estimates that the HHP 20 is in the portrait orientation (S50). Since the association does not need to be changed when moving to the right side, the process ends.

  Also in the present embodiment, the position calculation unit 31 may start the position calculation after step S32 or S34, or may perform the position calculation immediately after step S10. When the position calculation is started after step S32 or S34, a certain distance required for estimating the direction is treated as a margin.

  As described above, the HHP 20 of the present embodiment can prevent the direction of the HHP 20 from being estimated by a slight movement not intended by the user.

  In the present embodiment, a description will be given of an HHP 20 that estimates the direction of the HHP 20 based on time instead of distance, and thereby suppresses estimation of the direction of the HHP 20 by a slight movement that the user does not intend.

  FIG. 13 is a diagram illustrating an example of a functional block diagram of the control unit 25. In FIG. 13, components denoted by the same reference numerals in FIG. 11 perform similar functions, and thus only the main components of the present embodiment will be described in some cases. The control unit 25 in FIG. 13 includes a time measuring unit 37. The time measuring unit 37 starts measuring the elapsed time when the moving direction detecting unit 31a detects the rightward or leftward movement. When the moving direction changes, the measurement of the elapsed time is restarted from zero. Further, when a certain time has elapsed since the start of the movement, the image position corresponding unit 34 is notified of the fact.

  The fixed time is stored in the ROM 28. Alternatively, it may be set by the user from the OPU 26 and stored in the DRAM 29.

  FIG. 14 is an example of a flowchart illustrating a procedure for detecting the orientation of the HHP 20 with respect to the recording medium 12 and setting the relative position of the image data with respect to the nozzle 61. In the description of FIG. 14, differences from FIG. 12 will be mainly described.

  If it is determined in step S30 that the movement to the left has been made, the time measuring unit 37 starts measuring the elapsed time, and determines whether the movement to the left has been continued for longer than a predetermined time (S36). If the movement to the left and right for less than the predetermined time is detected, the process returns to step S20, and the start position (initial position) of image formation is set. This is because there is a possibility that the start position of image formation is outside the area of the recording medium 12. Also, if the HHP 20 has moved a predetermined distance or more before the predetermined time has elapsed, the process returns to step S20 for the same reason.

  If the HHP 20 stops before the fixed time has elapsed, the time measured by the time measuring unit 37 becomes zero. This is because there is a high possibility that the user has performed an unintended movement.

  Until the determination in step S36 becomes Yes, the process returns to step S20, and is performed again from the detection of the movement.

  If the determination in step S36 is Yes, as in the first embodiment, the direction detection unit 32 estimates that the HHP 20 is in the horizontal direction, and the image position corresponding unit 34 changes the association between the nozzle 61 and the image data (S40).

  If it is determined in step S30 that the movement has been made to the right, the time measurement unit 37 starts measuring time, and determines whether or not the movement to the right has been continued for longer than a predetermined time (S38). The determination method is the same as in step S36. The fixed time in steps S36 and S38 may be the same or different. Since the fixed time appropriate for the user is considered to be different depending on the shape and the moving direction of the recording medium 12, the optimum fixed time can be set by the different fixed times in steps S36 and S38.

  Until the determination in step S38 becomes Yes, the process returns to step S20, and is performed again from the detection of the movement.

  If the determination in step S38 is Yes, the orientation detection unit 32 estimates that the HHP 20 is in the portrait orientation (S50). Since the association does not need to be changed when moving to the right side, the process ends.

  Also in the present embodiment, the position calculation unit 31 may start the position calculation after step S36 or S38, or may perform the position calculation immediately after step S10. In this case, a certain distance required for estimating the direction is treated as a margin.

  As described above, the HHP 20 of the present embodiment can prevent the direction of the HHP 20 from being estimated by a slight movement not intended by the user. If the user moves slowly, the margin can be made smaller than in the second embodiment.

  Further, the combination of the second and third embodiments may be used to estimate the direction of the HHP 20 when either one of a movement longer than a certain distance or a movement longer than a certain time is satisfied.

  In the first to third embodiments, the direction detecting unit 32 estimates the direction of the HHP 20 by detecting the moving direction by the moving direction detecting unit 31a. In the present embodiment, an HHP 20 that detects the direction of the HHP 20 using a human sensor will be described.

  FIG. 15 is an example of a diagram for explaining the motion sensors 41a to 41d arranged on the HHP 20. FIG. 15A shows a perspective view, and FIG. 15B shows a top view. In FIG. 15, the HHP 20 is regarded as a cube, and human sensors 41 a to 41 d are arranged on four sides of the HHP 20.

  The human sensors 41a to 41d are sensors that detect a person within a predetermined distance from the HHP 20. As the human sensors 41a to 41d, for example, pyroelectric sensors that detect changes in infrared rays are used. That is, when a change in the surrounding temperature is sensed, the presence of a person is detected. In addition to infrared light, ultrasonic waves or visible light (camera) may be used.

  Therefore, the human sensors 41a to 41d detect that a person exists within a predetermined distance from the four side surfaces of the HHP 20. As shown in FIG. 15C, when the HHP 20 is oriented vertically with respect to the recording medium 12, the lower human sensor 41d detects a person. As shown in FIG. 15D, when the HHP 20 is oriented sideways with respect to the recording medium 12, the human sensor 41a on the left side detects the user. As is clear from FIGS. 15C and 15D, the predetermined distance needs to be at least longer than the length of the recording medium 12. On the other hand, the sensitivities of the human sensors 41a to 41d on each side need not be the same.

  FIG. 16 shows an example of a hardware configuration diagram of the HHP 20. In FIG. 16, components denoted by the same reference numerals in FIG. 4 perform similar functions, and thus only the main components of the present embodiment will be described in some cases. The HHP 20 of this embodiment has four motion sensors 41 a to 41 d, each of which is connected to the control unit 25.

  FIG. 17 is a diagram illustrating an example of a functional block diagram of the control unit 25 in the present embodiment. In FIG. 17, components denoted by the same reference numerals in FIG. 5 perform the same function, and thus only the main components of the present embodiment will be described in some cases. The control unit 25 in FIG. 17 includes a person detection unit 38. The human detection unit 38 analyzes signals from the human presence sensors 41a to 41d and determines whether each of the human presence sensors 41a to 41d has detected a human.

The direction detection unit 32 estimates the direction of the HHP 20 according to the detection result of the person detection unit 38 as follows.
・ The lower human sensor detects a person ... Vertical (top nozzle upward)
・ The human sensor on the left side detects a person ... Landscape (Lead nozzle at left)
・ The human sensor on the right side detects a person ... Landscape (first nozzle to the right)
・ The upper human sensor detects a person ... Vertical (first nozzle downward)
Therefore, since the direction of the nozzle 61 can be detected as well as whether the HHP 20 is portrait or landscape, the orientation of the HHP 20 can be estimated more finely than in the first to third embodiments.

  FIG. 18 is an example of a flowchart illustrating a procedure for detecting the orientation of the HHP 20 with respect to the recording medium 12 and setting the relative position of the image data with respect to the nozzle 61. The process of FIG. 18 is repeatedly executed while the power of the HHP 20 is ON.

  First, the person detection unit 38 determines whether or not the human sensor 41a on the left side has detected a person (S110).

  If the determination in step S110 is No, the human detection unit 38 determines whether the right human sensor 41b has detected a human (S120).

  If the determination in step S120 is No, the human detection unit 38 determines whether or not the upper human sensor 41c has detected a human (S130).

  If the determination in step S130 is No, the human detection unit 38 determines whether the lower human sensor 41d has detected a human (S140).

  If the determination in step S140 is No, the process returns to step S110. If the determination in step S140 is Yes, the process ends when an opportunity to start image formation is detected, and image formation starts (step S150). Yes). That is, the ejection of the ink is started. Until a trigger to start the image formation is detected (No in S150), the process returns to step S110 because the user may change the arrangement of the HHPs 20.

  If the determination in steps S110 to S130 is Yes, the human detection unit 38 determines whether or not another human sensor has detected a human (S160). If two or more human sensors have reacted, the direction cannot be specified, so the detection of the human is repeated from step S110.

  If the determination in step S160 is No, the orientation detection unit 32 estimates the orientation of the HHP 20, and the image position correspondence unit 34 changes the association between the nozzle 61 and the image data (S170).

  For example, the correspondence when the human sensor 41a on the left side detects a person may be the same as in FIGS. 9B and 9C. The association when the human sensor 41b on the right side detects a person will be described with reference to FIGS. FIG. 19A is a diagram illustrating the correspondence between the nozzles 61 and the image data when the HHP 20 is oriented sideways with respect to the recording medium 12 (the first nozzle in the right direction). In the standard state, the head nozzle 61s is associated with the origin at the upper left of the image data 105, and the nozzles 61 after the head are associated with the image on the left side of the image data. On the other hand, since the HHP 20 is oriented sideways with respect to the recording medium 12, if the image is formed as it is, the image protrudes from the recording medium 12.

  Therefore, as shown in FIG. 19B, the image position corresponding unit 34 changes the relative position of the image data with respect to the HHP 20. That is, the last nozzle 61e is associated with the origin at the upper left of the image data, and the nozzles 61 other than the last are associated with the upper image of the image data corresponding to the position of the nozzle. By doing so, image data can be formed on the recording medium 12.

  Next, the association when the upper human sensor 41c detects a person will be described with reference to FIGS. FIG. 19C is a diagram illustrating the correspondence between the nozzles 61 and image data when the HHP 20 is oriented vertically (the first nozzle downward) with respect to the recording medium 12. Also in this case, if the image is formed as it is, the image protrudes from the recording medium 12.

  Therefore, as shown in FIG. 19D, the image position corresponding unit 34 changes the relative position of the image data with respect to the HHP 20. That is, the last nozzle 61e is associated with the origin at the upper left of the image data, and the nozzles 61 other than the last are associated with the image on the left side of the image data corresponding to the position of the nozzle 61. By doing so, image data can be formed on the recording medium 12.

  When the association between the nozzle 61 and the image data is changed, as shown in step S150, an image forming start is detected by detecting a trigger to start the image forming.

  As described above, the HHP 20 of the present embodiment uses the human sensor to detect not only whether the HHP 20 is in the vertical direction or the horizontal direction but also the direction of the leading nozzle 61 s, and further restricts the direction of the HHP 20. Can be reduced.

  In this embodiment, the HHP 20 that estimates the initial position with respect to the recording medium 12 instead of the orientation of the HHP 20 will be described. Thus, the user can start image formation from the upper right of the recording medium 12 as well.

  FIG. 20 illustrates an example of a functional block diagram of the control unit 25 in the present embodiment. In FIG. 20, components denoted by the same reference numerals in FIG. 5 perform the same function, and thus, only the main components of the present embodiment will be mainly described in some cases. The control unit 25 in FIG. 20 includes an initial position detection unit 39. The initial position detection unit 39 detects the start position (initial position) of image formation of the HHP 20 on the recording medium 12 according to the movement direction calculated by the movement direction detection unit 31a. Details will be described with reference to FIG.

  FIG. 21 shows an arrangement example when the HHP 20 is arranged on the recording medium 12 in this embodiment. In FIG. 21A, the HHP 20 is oriented vertically with respect to the recording medium 12. On the other hand, in FIG. 21B, the HHP 20 is vertically oriented with respect to the recording medium 12, but the start position of image formation is at the upper right of the recording medium 12. Therefore, in the case of FIG. 21B, the HHP 20 needs to change the relative position of the image data with respect to the HHP 20.

  When arranged as shown in FIG. 21B, the user should move the HHP 20 to the left. Therefore, when the movement of the HHP 20 to the left is detected, the initial position detection unit 39 detects that the position of the HHP 20 with respect to the recording medium 12 (the start position of image formation) is at the upper right of the recording medium 12. That is, in the first to third embodiments, the direction of the HHP 20 with respect to the recording medium 12 is detected based on the moving direction. In the present embodiment, the start position of image formation is detected.

  When the start position of the image formation is detected, the image position corresponding unit 34 sets the relative position of the image data with respect to the HHP 20. As shown in FIG. 22 (c), the leading nozzle 61s is associated with the upper right corner of the image data, and the leading nozzle 61 is associated with the image on the right side of the image data corresponding to the position of the nozzle 61.

  FIG. 22 is an example of a flowchart illustrating a procedure for detecting the orientation of the HHP 20 with respect to the recording medium 12 and setting the relative position of the image data with respect to the nozzle 61. FIG. 22 mainly describes differences from FIG. 10A.

  If it is determined in step S30 that the image has moved to the left, the initial position detection unit 39 detects that the start position of image formation is at the upper right (S39).

  In this case, the image position corresponding unit 34 sets the relative position of the image data with respect to the HHP 20 by changing the association between the nozzle and the image data (S41).

  On the other hand, if it is determined in step S30 that the image has been moved to the right, the start position of image formation can be estimated to be at the upper left, and the process ends.

  Therefore, according to the present embodiment, by detecting the moving direction, the start position of image formation of the HHP 20 can be detected, and the relative position of the image data with respect to the HHP 20 can be set.

  It is unknown whether the HHP 20 should be determined as in the first embodiment or the present embodiment. Therefore, it is preferable that the user designates the HHP 20 from the OPU 26 or the like.

<Other application examples>
As described above, the best mode for carrying out the present invention has been described using the embodiment. However, the present invention is not limited to the embodiment, and various modifications may be made without departing from the gist of the present invention. And substitutions can be made.

  For example, in the above embodiment, the direction of movement to the right or left is detected. However, when the nozzles 61 are arranged in parallel with the horizontal direction of the main body of the HHP 20, the movement in the downward or upward direction may be detected. obtain.

  In addition, the hardware configuration diagram in FIG. 4 and the functional block diagrams in FIG. 5 and the like are divided according to main functions in order to facilitate understanding of processing by the HHP 20. The present invention is not limited by the way of dividing the processing unit or the name. The processing of the HHP 20 can be divided into more processing units according to the processing content. Further, it is also possible to divide the processing unit so that one processing unit includes more processing.

  In the present embodiment, an image is formed by discharging ink, but an image may be formed by irradiating visible light, ultraviolet light, infrared light, laser, or the like. In this case, for example, a recording medium 12 that responds to heat or light is used. Further, a transparent liquid may be discharged. In this case, visible light is obtained when light in a specific wavelength range is irradiated. Further, a conductive metal, resin, paste, or the like may be discharged.

  The HHP 20 may be moved by the user, or may move on the surface of the recording medium 12 by self-propelled by a motor or the like.

  Note that the image position corresponding unit 34 is an example of a relative position setting unit, and the recording head control unit 35 is an image forming unit. The direction detecting unit 32 is an example of a direction estimating unit, the determining unit 36 is an example of a determining unit, the time measuring unit 37 is an example of a time measuring unit, and the initial position detecting unit 39 is an example of an initial position detecting unit. is there. The human sensors 41a to 41d are examples of a human detection sensor. The processing method described in the first to fifth embodiments is an example of the liquid discharging method. The image forming method performed by the HHP 20 is an example of the image forming method.

Reference Signs List 30: navigation sensor 31: position calculating unit 31a: moving direction detecting unit 32: direction detecting unit 33: image processing unit 34: image position corresponding unit 35: recording head control unit 36: determining unit 37: time measuring unit 38: human detection Unit 39: Initial position detection unit 41a to 41d: Human sensor 61: Nozzle

Japanese Patent No. 5033247

Claims (10)

A liquid ejecting apparatus that forms an image while moving on a recording medium,
Position detecting means for detecting a position on the recording medium,
Moving direction detecting means for detecting a moving direction of the liquid ejection device,
Direction estimating means for estimating the direction of the liquid ejecting apparatus with respect to the recording medium according to the moving direction detected by the moving direction detecting means;
Determining means for determining whether or not the movement distance in the movement direction using the position of the liquid ejection device is greater than a certain distance;
When the determining unit determines that the moving distance in the moving direction is larger than a certain distance , the discharging position on the recording medium is changed according to the direction of the liquid discharging device with respect to the recording medium estimated by the direction estimating unit. Position setting means to be set;
Image forming means for forming an image corresponding to the ejection position set by the position setting means on the recording medium,
A liquid ejection device having: It has a time measuring means for measuring an elapsed time of continuously moving in the moving direction,
2. The liquid ejection apparatus according to claim 1 , wherein when the elapsed time is longer than a predetermined time, the position setting unit sets an ejection position on the recording medium according to the moving direction. If the moving distance in the moving direction is longer than the certain distance, or if at least one of the case where the elapsed time is longer than the certain time is satisfied, the position setting means sets the position according to the moving direction. 3. The liquid ejection device according to claim 2 , wherein the ejection position on the recording medium is set. 4. The liquid ejecting apparatus according to claim 3 , wherein the fixed distance differs depending on the moving direction, and the fixed time differs depending on the moving direction. A liquid ejection device that has a plurality of human detection sensors that detect the presence of a person arranged on each of a plurality of side surfaces and forms an image while moving on a recording medium,
Position detecting means for detecting a position on the recording medium,
Orientation estimation means for detecting the orientation of the liquid ejection device with respect to the recording medium according to the side surface on which the human detection sensor that has detected the presence of a human is arranged;
Position setting means for setting an ejection position on the recording medium according to the orientation of the liquid ejection device with respect to the recording medium estimated by the orientation estimation means;
Image forming means for forming an image corresponding to the ejection position set by the position setting means on the recording medium,
A liquid ejection device having: Moving direction detecting means for detecting a moving direction of the liquid ejection device,
Anda initial position detecting means for detecting the initial position of the liquid ejection device for said recording medium in accordance with the moving direction,
Said position setting means, in response to the initial position where the initial position detecting unit detects a liquid discharge apparatus according to claim 1 or 5 for setting the discharge position on the recording medium. A liquid ejection method performed by a liquid ejection apparatus that forms an image while moving on a recording medium,
Position detecting means for detecting a position on the recording medium,
Moving direction detecting means for detecting a moving direction of the liquid ejection device;
A direction estimating means for estimating a direction of the liquid ejection device with respect to the recording medium in accordance with the moving direction detected by the moving direction detecting means;
Determining means for determining whether or not the movement distance in the movement direction is greater than a certain distance using the position of the liquid ejection device;
When the determining unit determines that the moving distance in the moving direction is larger than a certain distance, the position setting unit sets the recording medium in accordance with the orientation of the liquid ejection device with respect to the recording medium estimated by the orientation estimating unit. Setting the upper ejection position;
Image forming means for forming an image corresponding to the ejection position set by the position setting means on the recording medium;
A liquid ejection method comprising: A liquid discharge method performed by a liquid discharge device that has a plurality of human detection sensors that detect the presence of a person arranged on each of a plurality of side surfaces and forms an image while moving on a recording medium,
Position detecting means for detecting a position on the recording medium,
A direction estimating means for detecting a direction of the liquid ejection device with respect to the recording medium according to the side surface on which the human detection sensor that has detected the presence of a person is arranged;
Position setting means for setting an ejection position on the recording medium according to the orientation of the liquid ejection device with respect to the recording medium estimated by the orientation estimation means;
Image forming means for forming an image corresponding to the ejection position set by the position setting means on the recording medium;
A liquid ejection method comprising: A liquid ejection device that forms an image while moving on a recording medium,
Position detecting means for detecting a position on the recording medium,
Moving direction detecting means for detecting a moving direction of the liquid ejection device,
Direction estimating means for estimating the direction of the liquid ejecting apparatus with respect to the recording medium according to the moving direction detected by the moving direction detecting means;
Determining means for determining whether or not the movement distance in the movement direction using the position of the liquid ejection device is greater than a certain distance;
When the determining unit determines that the moving distance in the moving direction is larger than a certain distance , the discharging position on the recording medium is changed according to the direction of the liquid discharging device with respect to the recording medium estimated by the direction estimating unit. Position setting means to be set;
A program functioning as image forming means for forming an image corresponding to the ejection position set by the position setting means on the recording medium. A liquid ejection device that has a plurality of human detection sensors that detect the presence of a person arranged on each of a plurality of side surfaces and forms an image while moving on a recording medium,
Position detecting means for detecting a position on the recording medium,
Orientation estimation means for detecting the orientation of the liquid ejection device with respect to the recording medium according to the side surface on which the human detection sensor that has detected the presence of a human is arranged;
Position setting means for setting an ejection position on the recording medium according to the orientation of the liquid ejection device with respect to the recording medium estimated by the orientation estimation means;
A program functioning as image forming means for forming an image corresponding to the ejection position set by the position setting means on the recording medium.

Images