recording device

Abstract

The recording device is provided with: a liquid ejection section that is capable of rotating around a prescribed rotation axis, circulates a liquid inside, and ejects the liquid; and a control section that controls the operation of the liquid ejection section so as to reciprocate along a printing direction and eject liquid droplets. The control section controls the position and posture of the liquid ejection section so as to start printing from the positive pressure side of the liquid circulating inside the liquid ejection section.

Description

Technical Field

[0001] The disclosed implementation relates to a recording device. Background Technology

[0002] As a recording device, inkjet printers and inkjet plotters are known to utilize inkjet recording methods that record images, etc., by ejecting liquid or droplets from the nozzle. Regarding the aforementioned inkjet recording devices, techniques have been proposed aimed at ensuring stable ejection performance.

[0003] Prior art literature

[0004] Patent documents

[0005] Patent Document 1: JP Japanese Patent Application Publication No. 2016-159514 Summary of the Invention

[0006] -Methods for solving the problem-

[0007] One embodiment of the recording apparatus includes: a liquid ejection section capable of rotating about a predetermined rotation axis to circulate liquid internally and eject liquid; and a control section controlling the operation of the liquid ejection section to reciprocate along the printing direction and eject droplets. The control section controls the position and orientation of the liquid ejection section to initiate printing from the positive pressure side of the liquid circulating internally within the liquid ejection section. Attached Figure Description

[0008] Figure 1 This is a schematic diagram showing an outline of the liquid ejection system involved in the embodiment.

[0009] Figure 2 This is a schematic diagram showing an outline of the liquid ejection system involved in the embodiment.

[0010] Figure 3 This is a perspective view schematically showing the external structure of the liquid ejector head according to the embodiment.

[0011] Figure 4 This is a top view of the liquid ejector head involved in the embodiment.

[0012] Figure 5 This is a diagram schematically illustrating the internal flow path of the liquid nozzle according to the embodiment.

[0013] Figure 6 This is a diagram illustrating a schematic hardware structure example of the liquid ejection system according to the embodiment.

[0014] Figure 7 This is a block diagram illustrating an example of the functional structure of the various components of the liquid ejection system according to the embodiment.

[0015] Figure 8 This is a diagram showing a summary of the head control data involved in the implementation method.

[0016] Figure 9 This is a diagram showing an outline (one) of the motion control of the liquid nozzle involved in the embodiment.

[0017] Figure 10 This is a diagram illustrating one of the methods for reversing the liquid nozzle according to the embodiment.

[0018] Figure 11 This is a diagram illustrating a method for reversing the liquid nozzle according to the embodiment (second one).

[0019] Figure 12 This is a diagram showing an outline (second part) of the motion control of the liquid nozzle involved in the embodiment.

[0020] Figure 13 This is a flowchart illustrating an example of the processing sequence performed by the control unit involved in the implementation.

[0021] Figure 14 This is a schematic diagram showing the general structure of the liquid ejection system involved in the modified example.

[0022] Figure 15 This is a flowchart illustrating an example of the processing sequence performed by the control unit involved in the variation.

[0023] Figure 16 This is a diagram showing the outline of the liquid ejection system involved in the modified example. Detailed Implementation

[0024] Hereinafter, embodiments of the recording apparatus disclosed in this application will be described in detail with reference to the accompanying drawings. However, the invention described below is not intended to limit the scope of this application.

[0025] In the following embodiments, as an example of the recording device disclosed in this application, a liquid ejection system in which a liquid ejection head that ejects liquid (or droplets) in an inkjet manner is mounted on a robotic arm will be described. The recording device disclosed in this application can be applied not only to inkjet printers and inkjet plotters that utilize inkjet recording, but also to various devices that eject liquid (or droplets) in an inkjet manner.

[0026] <<Overview of Liquid Ejection Systems>>

[0027] use Figure 1 as well as Figure 2 The outline of the liquid ejection system involved in the implementation method will be described. Figure 1 as well as Figure 2This is a schematic diagram showing an outline of the liquid ejection system involved in the embodiment.

[0028] like Figure 1 or Figure 2 As shown, the liquid ejection system 1 includes a control unit 100, a robotic arm 200, a liquid ejection head 300, and a circulation device 400.

[0029] The control unit 100 is, for example, built into the robot arm 200. Alternatively, the control unit 100 can be mounted on an external device independent of the robot arm 200, and communicatively connected to the robot arm 200. The control unit 100 outputs commands to the robot arm 200 to control its movements. Thus, the control unit 100 controls the position and orientation of the liquid nozzle 300 (and the circulation device 400) mounted at the foremost end of the robot arm 200 via the robot arm 200.

[0030] The control unit 100 can move the liquid nozzle 300 (and the circulation device 400) via the robotic arm 200. This allows the control unit 100 to change the position of the liquid nozzle 300 (and the circulation device 400). Furthermore, the control unit 100 can rotate the liquid nozzle 300 (and the circulation device 400) around a predetermined axis of rotation (e.g., the Y-axis, Z-axis) via the robotic arm 200. This allows the control unit 100 to change the orientation, angle, and other posture of the liquid nozzle 300 (and the circulation device 400).

[0031] The robotic arm 200 operates according to instructions from the control unit 100, causing changes in the position and orientation of the liquid nozzle 300. The robotic arm 200 is, for example, mounted on a base 5 placed on a horizontal surface, indoors or outdoors. Alternatively, the robotic arm 200 can be a movable structure on the base 5. The robotic arm 200 is composed of multiple components assembled to freely extend, flex, and rotate. The robotic arm 200 is not particularly limited to any particular type, provided it possesses degrees of freedom to perform changes in movement, orientation, etc., required for the liquid nozzle 300. Figure 1 , Figure 2 The structure shown.

[0032] The liquid ejector head 300 is a circulating inkjet head that circulates liquid internally and ejects the liquid. The liquid ejector head 300 functions as a liquid ejection section that ejects liquid onto the approximately horizontal working surface SF1_B1 of the object B1 to be printed (recorded) and the approximately vertical working surface SF2_B1 of the object B1. The liquid ejector head 300, together with the circulation device 400, is mounted at the foremost end of the robotic arm 200.

[0033] The circulation device 400 supplies liquid to the liquid nozzle 300 by controlling the circulation pressure of the liquid circulating between the nozzle and the liquid nozzle 300. The circulation device 400 and the liquid nozzle 300 are mounted together at the foremost end of the robotic arm 200. The circulation device 400 and the liquid nozzle 300 are integrated and their positions and orientations can be changed.

[0034] However, the circulating pressure of the liquid supplied to the liquid ejector head 300 is affected by changes in the position and orientation of the liquid ejector head 300 based on the robotic arm 200. In particular, when the liquid ejection volume is large, the impact on the circulating pressure is significant, and ejection leakage may occur. In view of this problem, this application proposes a liquid ejection system 1 that can suppress the occurrence of ejection leakage and ensure the quality of the recorded image.

[0035] <<Example of Liquid Jet Head Structure>>

[0036] use Figures 3-5 The liquid ejector head 300 involved in the embodiment will be described. Figure 3 This is a perspective view schematically showing the external structure of the liquid ejector head according to the embodiment. Figure 4 This is a top view of the liquid ejector head involved in the embodiment. Figure 5 This is a diagram schematically illustrating the internal flow path of the liquid nozzle according to the embodiment.

[0037] like Figure 3 As shown, the liquid nozzle 300 includes a housing comprising a box-shaped component 310 and a flat plate-shaped component 320. Within the housing of the liquid nozzle 300, a first flow path RT1 for supplying liquid from the circulation device 400 to the interior of the nozzle, and a second flow path RT2 for returning liquid recovered from the interior of the nozzle to the circulation device 400. Figure 4 or Figure 5 As shown, the component 320 of the liquid ejector head 300 has a supply port P for supplying liquid into the head through the first flow path RT1. in And the outlet P through which liquid is discharged from inside the head via the second flow path RT2. out .

[0038] like Figure 3 As shown, the liquid nozzle 300 includes a supply reservoir 301, a supply manifold 302, a recovery manifold 303, a recovery reservoir 304, and an element 305.

[0039] The supply reservoir 301 has an elongated shape extending along the long side (Y-axis direction) of the liquid nozzle 300 and is connected to the supply manifold 302. The supply reservoir 301 has internal flow paths. For example... Figure 4 or Figure 5As shown, through the first flow path RT1 and the supply port P in The liquid is supplied to the supply reservoir 301, and the liquid stored in the flow path of the supply reservoir 301 is sent out to the supply manifold 302.

[0040] The supply manifold 302 has an elongated shape extending near the front of the recovery reservoir 304 in the short-side direction (X-axis direction) of the liquid outlet head 300. Internally, the supply manifold 302 has the flow path of the supply reservoir 301 and the flow path connected to the element 305. For example... Figure 4 or Figure 5 As shown, the liquid supplied from the supply reservoir 301 to the supply manifold 302 is then supplied from the supply manifold 302 to the element 305.

[0041] The recovery manifold 303 has an elongated shape extending near the front of the supply reservoir 301 in the short side direction (X-axis direction) of the liquid outlet head 300. Internally, the recovery manifold 303 has the flow path of the recovery reservoir 304 and the flow path connected to the element 305. For example... Figure 4 or Figure 5 As shown, liquid that is not ejected from element 305 (ejection hole 305h) to the outside is sent to recovery manifold 303.

[0042] The recovery reservoir 304 has an elongated shape extending along the long side (Y-axis direction) of the liquid outlet head 300 and is connected to the recovery manifold 303. The recovery reservoir 304 has internal flow paths. For example... Figure 4 or Figure 5 As shown, the liquid sent from the recovery manifold 303 to the recovery reservoir 304 and stored in the flow path of the recovery reservoir 304 passes through the outlet P. out And the second flow path RT2 is fed back to the circulation device 400.

[0043] Component 305 has a spray hole 305h. Component 305 draws liquid from supply manifold 302 by negative pressure generated by a pressure chamber (not shown), and sprays the drawn liquid out of spray hole 305h toward object B1 by positive pressure generated by a pressure chamber (not shown).

[0044] <<Example of Hardware Structure for a Liquid Ejection System>>

[0045] Next, the general structure of the liquid ejection system involved in the embodiment will be described. Figure 6 This is a diagram illustrating a schematic hardware structure example of the liquid ejection system according to the embodiment. Additionally, Figure 6 This is a diagram that roughly illustrates an example of the hardware structure of a droplet ejection system; it is not necessarily limited to... Figure 6 The example shown. Additionally, in Figure 6In the example shown, arrows represent the flow of data or signals, and solid lines represent physical connections.

[0046] like Figure 6 As shown, the liquid ejection system 1 is equipped with various sensors. Specifically, the liquid ejection system 1 includes a camera 21, a distance sensor 22, an attitude sensor 23, an acceleration sensor 24, and an orientation sensor 25.

[0047] Camera 21 has the function of photographing the object B1 (work surface SF1_B1, work surface SF2_B1) being printed (recorded). Camera 21 is mounted at any position on the robot arm 200. The liquid ejection system 1 can have multiple cameras 21 with different settings. Camera 21 outputs the captured images to control unit 100. Alternatively, camera 21 can be a wide-angle camera. In this case, control unit 100 extracts extraction points from the image above the liquid ejection system 1 captured by the wide-angle camera. Furthermore, control unit 100 can use the extracted feature points as a hypothetical viewpoint to generate an overhead image of the recording (printing) status of object B1 (work surface SF1_B1, work surface SF2_B1). Thus, control unit 100 can determine the recording (printing) status.

[0048] Distance sensor 22 detects the distance between the object B1 (working surface SF1_B1, working surface SF2_B1) being recorded (printed) and the liquid nozzle 300. Distance sensor 22 can be implemented using a ToF (Time of Flight) sensor, a depth sensor (also called a depth camera) that acquires depth maps or depth images, etc. Distance sensor 22 is positioned at any position within the circulation device 400 capable of detecting the distance between the object B1 (working surface SF1_B1, working surface SF2_B1) being recorded (printed) and the liquid nozzle 300. Distance sensor 22 outputs the detection result to control unit 100. Based on the distance detected by distance sensor 22, control unit 100 can perform actions corresponding to the relative positional relationship between the object B1 (working surface SF1_B1, working surface SF2_B1) and the liquid nozzle 300.

[0049] The attitude sensor 23 detects the attitude of the liquid nozzle 300. The attitude sensor 23 can be implemented, for example, by a 3-axis or 9-axis gyroscope sensor. The attitude sensor 23 detects the attitude of the liquid nozzle 300, such as roll, pitch, and yaw. The attitude sensor 23 is positioned at any location within the circulation device 400. That is, in the liquid ejection system 1, the attitude of the circulation device 400 is detected as the attitude of the liquid nozzle 300. The attitude sensor 23 outputs the detection result to the control unit 100. Based on the attitude detected by the attitude sensor 23, the control unit 100 can determine the attitude of the liquid nozzle 300.

[0050] Accelerometer 24 detects the acceleration applied to the liquid nozzle 300. Accelerometer 24 is installed at any position within the circulation device 400. That is, in the liquid ejection system 1, the acceleration applied to the circulation device 400 is detected as the acceleration applied to the liquid nozzle 300. Accelerometer 24 outputs the detection result to control unit 100. Based on the detection result of accelerometer 24 and the detection result of orientation sensor 25 (described later), control unit 100 can, for example, calculate the current position of the liquid nozzle 300 relative to its position at the start of printing.

[0051] Orientation sensor 25 detects the orientation (direction) of the liquid nozzle 300. Orientation sensor 25 can be implemented, for example, by a geomagnetic sensor. Orientation sensor 25 is installed at any position within the circulation device 400. That is, in the liquid ejection system 1, the orientation of the circulation device 400 is detected as the orientation of the liquid nozzle 300. Orientation sensor 25 outputs the detection result to control unit 100. Based on the detection result of orientation sensor 25, control unit 100 can calculate the current orientation of the liquid nozzle 300 relative to its orientation at the start of printing.

[0052] Additionally, the aforementioned attitude sensor 23, acceleration sensor 24, and orientation sensor 25 can also be installed via an IMU (Inertial Measurement Unit). Furthermore, the liquid ejection system 1 can also be equipped with... Figure 6 Other sensors besides those shown in the examples include ultrasonic sensors, temperature sensors, and human sensors.

[0053] Furthermore, the liquid ejection system 1 includes a drive mechanism for driving the robotic arm 200. This drive mechanism includes, for example, a movable part 31 comprising links (bones) constituting the robotic arm 200, joints (joints), an end effector, an actuator 32 for driving the movable part 31, and an encoder 33 for detecting the rotation angle (position) of the motor. Furthermore, the drive mechanism appropriately controls the position and posture of the liquid ejection head 300 by cooperating with the aforementioned sensors. The end effector of the movable part 31 is connected to the liquid ejection head 300 and the circulation device 400. The encoder 33 can be an encoder using any detection method, such as optical or magnetic. Additionally, the links constituting the robotic arm 200 can be either series links or parallel links.

[0054] In addition, the liquid ejection system 1 includes an ejection pump 34, a suction pump 35, and a liquid ejection head 300.

[0055] The ejection pump 34 passes through the first flow path RT1 and the supply port P. in The liquid stored in the tank (not shown) is supplied to the liquid nozzle 300. The ejection pump 34 generates positive pressure to deliver the liquid stored in the tank to the liquid nozzle 300. For example, the ejection pump 34 can deliver the liquid stored in the tank to the liquid nozzle 300 at a pre-set supply pressure.

[0056] Suction pump 35 through discharge port P out The second flow path RT2 delivers liquid that was not ejected from the liquid nozzle 300 and was recovered inside the nozzle to the tank. The suction pump 35 generates a negative pressure to suction the recovered liquid inside the nozzle and return it to the tank. The suction pump 35 can, for example, deliver the liquid sucked from the liquid nozzle 300 to the tank 201 at a pre-set recovery pressure.

[0057] The ejection pump 34 and the suction pump 35 can be assembled by positive displacement pumps such as rotary pumps or diaphragm pumps, such as gear pumps.

[0058] Furthermore, the liquid ejection system 1 includes a controller 10 that provides unified control over the system's operation. The controller 10 comprises a signal processing circuit 11, a CPU (Central Processing Unit) 12, a DRAM (Dynamic Random Access Memory) 13, a flash ROM (Read Only Memory) 14, a USB (Universal Serial Bus) connector 15, and a wireless communication unit 16, all interconnected via an internal bus 17. Additionally, although... Figure 2Although not shown in the diagram, the liquid ejection system 1 has various interfaces for inputting and outputting data with the camera 21, actuator 42, ejection pump 34, and suction pump 35. Furthermore, the liquid ejection system 1 may also include batteries or similar devices that supply power to the various components of the liquid ejection system 1.

[0059] The aforementioned sensors, actuators 32, encoders 33, ejector pumps 34, suction pumps 35, and signal processing circuits 11 are connected. The signal processing circuits 11 sequentially receive sensor data, pump data, and control signals received from external terminals 40, and store these data in designated locations within the DRAM 13 via the internal bus 17.

[0060] The sensor data, pump data, etc., stored in DRAM13 are used by CPU12 when controlling the operation of the liquid ejection system 1. Furthermore, this data is transmitted to external devices such as servers via wireless communication unit 16 as needed. Additionally, wireless communication unit 16 has communication functions for communicating with external devices, external terminals 40, etc., via networks such as Bluetooth (registered trademark), WiFi (registered trademark), wireless LAN (Local Area Network), and mobile communication networks.

[0061] For example, when the power to the liquid ejection system 1 is turned on, the CPU 12 reads the control program stored in the external memory 50 connected to the USB connector 15 and stores the read control program in the DRAM 13. In addition, the CPU 12 reads the control data (printing control data, posture control data) stored in the flash ROM 14 and stores the read control data in the DRAM 13.

[0062] Furthermore, the CPU 12 executes the operation control of the liquid ejection system 1 based on the sensor data, pump data, control data, etc., sequentially stored in the DRAM 13 by the signal processing circuit 11 as described above. For example, the CPU 12 determines the position and orientation of the liquid ejection head 300 based on the sensor data and control data sequentially stored in the DRAM 13. Based on the determined position and orientation of the liquid ejection head 300, a control command is generated and provided to the actuator 42. The CPU 12 outputs the generated control command to the actuator 42 via the signal processing circuit 11. Additionally, the CPU 12 generates control commands for the ejection pump 34 and the suction pump 35 based on the control data sequentially stored in the DRAM 13. The CPU 12 outputs the generated control commands to the ejection pump 34 and the suction pump 35 via the signal processing circuit 11.

[0063] In this way, the liquid ejection system 1 can uniformly control the operation of the system through the cooperation of hardware such as CPU 12 and the prescribed program such as the control program.

[0064] <<Examples of the functional structure of each component in Liquid Ejection System 1>>

[0065] Hereinafter, examples of the functional structure of each part of the liquid ejection system 1 according to the embodiment will be described. Figure 7 This is a block diagram illustrating an example of the functional structure of the various components of the liquid ejection system according to the embodiment. Additionally, Figure 7 This is an example of a functional structure representing the various parts of the liquid ejection system 1 using functional blocks. As long as the structure can realize the various functions of the liquid ejection system 1 according to the embodiment, it does not need to be particularly limited to... Figure 7 The example shown. Furthermore, Figure 7 This description illustrates the functions of each component in the liquid ejection system 1 according to the embodiment, omitting descriptions of other general structural elements. Furthermore, Figure 7 The structural elements of the various parts of the liquid ejection system 1 shown are functional conceptual elements and are not limited to specific components. Figure 7 The examples shown do not necessarily need to be physically structured as illustrated. For instance, the specific methods of distributing and merging functional blocks are not limited to those shown in the diagram; they can be distributed or merged functionally or physically in any unit, depending on various loads and usage conditions. Furthermore, in Figure 7 In the example shown, the thin solid line represents the flow of data or signals, while the thick solid line represents physical connections.

[0066] like Figure 7 As shown, the control unit 100 of the liquid ejection system 1 includes an input / output (IF) unit 110, a storage unit 120, and a control unit 130.

[0067] The input / output IF section 110 is a variety of interfaces used for inputting and outputting various data between the robot arm 200 and the circulation device 400.

[0068] Storage unit 120, for example, is composed of Figure 6 The storage unit 120 is composed of semiconductor memory elements such as DRAM 13 and flash ROM 14, as well as storage devices such as hard disks and optical disks. The storage unit 120 can store, for example, programs and data for implementing various processes executed by the control unit 130. The programs stored in the storage unit 120 include control programs for implementing processing functions corresponding to each part of the control unit 130. The programs stored in the storage unit 120 include an operating system (OS) and various application programs.

[0069] like Figure 7 As shown, the storage unit 120 includes a data storage unit 121 for printing control and a data storage unit 122 for head control.

[0070] The printing control data storage unit 121 stores printing control data for controlling the printing (recording) of the object B1. The printing control data includes information related to the size and shape of the object B1, printing attribute setting information, printing start position, printing end position information, and target values ​​of the pressure of the ejector pump 34 and the suction pump 35.

[0071] The head control data storage unit 122 stores head control data for controlling the position and posture of the liquid ejector head 300. The head control data includes setting information related to the posture of the liquid ejector head 300 towards the object B1 (working surface SF1_B1, working surface SF2_B1). Figure 8 This is a diagram showing a summary of the head control data involved in the implementation method.

[0072] like Figure 8 As shown, the head control data includes a "head movement posture" item and a "head orientation" item that are mutually corresponding. The "head movement posture" item sets the movement posture of the liquid ejector head 300 when printing (recording) on ​​object B1 (working surface SF1_B1, working surface SF2_B1). The "head orientation" item sets the supply port P, which determines the orientation of the liquid ejector head 300 for the path and return of the liquid ejector head 300 that reciprocates along the printing direction. in and discharge outlet P out Positional relationship.

[0073] exist Figure 8 In the example shown, when the movement posture is "roughly horizontal" and the movement is "going in the direction of travel", the information used to determine the orientation of the liquid ejector head 300 is set relative to the printing direction (head movement direction) and the supply port P. in "Right", outlet P out The relative positional relationship is "left". On the other hand, when the movement posture is "approximately horizontal" and the movement is "loop", the information used to determine the orientation of the liquid ejector head 300 is set relative to the printing direction (head movement direction) and the supply port P. in "Right", outlet P outThe relative positional relationship is "left". Therefore, when the liquid nozzle 300 is moving in a roughly horizontal position, printing always begins from the positive pressure side (the side with higher pressure) of the liquid circulating inside the liquid nozzle 300. Here, the positive pressure side refers to the supply side that supplies liquid to the liquid nozzle 300, or the upstream side of the liquid circulating inside the liquid nozzle 300. Furthermore, Figure 8 The printing direction and supply port Pi are shown. n Outlet P out The relative positional relationship between them is determined by the internal structure of the liquid nozzle 300 and the direction of liquid circulation. If the internal structure of the liquid nozzle 300 and the direction of liquid circulation are different, then of course... Figure 8 The printing direction and supply port P are shown. in Outlet P out The relative positional relationship between them has also been changed.

[0074] In addition, Figure 8 In the example shown, when the movement posture is "approximately vertical" and the movement is "going direction", the supply port P is set relative to the printing direction (head movement direction) as information used to determine the orientation of the liquid ejection head 300. in "Down", outlet P out The relative positional relationship is "up". On the other hand, when the moving posture is "approximately vertical" and the movement is "loop", the direction relative to the printing direction (head moving direction) and the supply port P are set as information used to determine the orientation of the liquid ejector head 300. in "Up", outlet P out The relative positional relationship is "down". Therefore, even when the movement direction of the liquid nozzle 300 is approximately perpendicular, printing always begins from the positive pressure side (supply side) of the liquid circulating inside the liquid nozzle 300. Furthermore, in Figure 7 In the example shown, information for determining the head's orientation is set for both the outgoing path and the return path. However, it is also possible to set only the head's orientation corresponding to the outgoing path and reverse it by 180 degrees in the return path.

[0075] Control unit 130 via Figure 5The controller 10 shown (including signal processing circuit 11, CPU 12, DRAM 13, etc.) is implemented. For example, commands described in the control program read from internal memory such as DRAM 13 by the processor such as CPU 12 are executed, making the internal memory a working area, thereby realizing various processes performed by the control unit 130. The program read from internal memory by the processor such as CPU 12 includes the OS and application programs. In addition, the control unit 130 can be implemented, for example, by an integrated circuit such as ASIC (Application Specific Integrated Circuit) or FPGA (Field-Programmable Gate Array).

[0076] <<Specific Examples of Motion Control Based on the Control Unit>>

[0077] The following is a specific example of motion control based on the control unit 130. Figure 9 This is a diagram showing an outline (one) of the motion control of the liquid nozzle involved in the embodiment. Figure 10 This is a diagram illustrating one of the methods for reversing the liquid nozzle according to the embodiment. Figure 11 This is a diagram illustrating a method for reversing the liquid nozzle according to the embodiment (second one). Figure 9 The diagram shows the operation of the liquid ejector head 300 during printing. Figure 9-1 300mm top view magnification of the liquid nozzle Figure 9-2 . Figure 9 In the example shown, it appears as if the liquid nozzle 300 leaves gaps during printing, but this is to illustrate the movement of the liquid nozzle 300 in a way that is easy to understand. That is, depending on the printing method, the position and orientation of the liquid nozzle 300 can be controlled to print on the printing area without gaps, or the position and orientation of the liquid nozzle 300 can be controlled to overlap the printing area to print on the printing area.

[0078] The control unit 130 controls the movement of the liquid ejector head 300 via the robot arm 200, causing it to reciprocate along the printing direction PD and eject liquid. The control unit 130 controls the movement of the robot arm 200 and the position and orientation of the liquid ejector head 300 so that printing begins from the positive pressure side of the liquid circulating inside the liquid ejector head 300. That is, the control unit 130 adjusts the orientation of the liquid ejector head 300 so that printing on the object B1 (working surface SF1_B1, working surface SF2_B1) always begins from the side where the element 305 on the supply reservoir 301 side with higher pressure is located.

[0079] Specifically, such as Figure 9 The illustration Figure 9-1 As shown, the control unit 130 refers to the head control data to control the orientation of the liquid ejector head 300, so that: when the movement posture of the liquid ejector head 300 is approximately horizontal (approximately horizontal relative to the XY plane), from the start of printing on the outgoing path OW to the end of printing, relative to the printing direction (+X direction), the supply port P in "Right", outlet P out "Left". In addition, such as Figure 9 Top view magnification Figure 9-2 As shown, when controlling the orientation of the liquid ejector head 300, the control unit 130 adjusts the orientation so that the arrangement direction of the element 305 is parallel to the direction orthogonal to the printing direction PD (Y-axis direction).

[0080] If the printing of loop OW (printing of 1 line) ends, the control unit 130 refers to the head control data to reverse the orientation of the liquid ejector head 300, so that from the start of printing of loop HW, which is the next predetermined line for printing, to the end of printing, the supply port P relative to the printing direction (-X direction)... in "Right", outlet P out "Left". The control unit 130 reverses the orientation of the liquid ejector head 300 by moving it 180 degrees in an arc around a predetermined rotation axis, so that no gap is generated in the printed line between the outgoing path OW and the return path HW. For example, as Figure 10 As shown, the control unit 130 is capable of controlling the discharge port P out As the axis of rotation AX r This causes the liquid ejector head 300 to move counterclockwise in a 180-degree arc. At this time, the orientation of the liquid ejector head 300 is reversed to prevent gaps from forming between the outgoing path OW and the returning path HW in the printed lines. Furthermore, as... Figure 11 As shown, the control unit 180 can also reverse the orientation of the liquid nozzle 300 by rotating it 180 degrees from its original position without changing the position of the liquid nozzle 300. In this case, after reversing the orientation of the liquid nozzle 300, the control unit 130 moves the liquid nozzle 300 to the printing start position of the next predetermined printing line. Alternatively, after the printing of the outgoing path OW is completed, the control unit 130 reverses the orientation of the liquid nozzle 300 at the maintenance area MA where the printing of the loop begins.

[0081] Furthermore, similar to the case of the outgoing path OW, the control unit 130 adjusts the orientation of the liquid ejector head 300 so that the arrangement direction of the components 305 is parallel to the direction orthogonal to the printing direction PD (Y-axis direction). Additionally, if the printing of loop HW (printing one line) ends, the control unit 130 refers to the head control data to reverse the orientation of the liquid ejector head 300, so that from the start of printing the next predetermined line of the outgoing path OW to the end of printing, relative to the printing direction (+X direction), the supply port P... in "Right", outlet P out "Left". In this case, the control unit 130 can control the supply port P. in As the axis of rotation AX r The liquid nozzle 300 is moved 180 degrees clockwise in an arc shape, thereby reversing the orientation of the liquid nozzle 300. Alternatively, the control unit 130 can also reverse the position of the liquid nozzle 300 by 180 degrees without changing its position, thereby reversing the orientation of the liquid nozzle 300.

[0082] exist Figure 9 In the example shown, the control unit 130 repeatedly reverses the orientation of the liquid ejector head 300 after each line (outbound or inbound) of printing is completed until all lines of printing on the working surface SF1_B1 of the object B1 are finished. Thus, while the control unit 130 reciprocates the liquid ejector head 300 in a roughly horizontal moving posture towards the working surface SF1_B1 of the object B1 and performs printing, the orientation of the liquid ejector head 300 is controlled so that printing always begins from the positive pressure side (the side with higher pressure) of the liquid circulating inside the control liquid ejector head 300. Therefore, the control unit 130 can suppress the occurrence of ejection omissions during printing in a roughly horizontal moving posture, ensuring the quality of the recorded image.

[0083] Figure 12 This is a diagram showing an outline (second part) of the motion control of the liquid nozzle involved in the embodiment. Figure 12 The diagram shows the operation of the liquid ejector head 300 during printing. Figure 12-1 300mm top view magnification of the liquid nozzle Figure 12-2 .like Figure 12 As shown, when the liquid ejector head 300 is moving in a roughly vertical position (roughly horizontal relative to the YZ plane), the control unit 130 also... Figure 9 The example shown similarly controls the position and orientation of the liquid ejector head 300 so that printing begins from the positive pressure side of the liquid circulating inside the liquid ejector head 300.

[0084] That is, the control unit 130 refers to the head control data to control the orientation of the liquid ejector head 300, so that when the movement posture of the liquid ejector head 300 is approximately vertical (approximately horizontal relative to the YZ plane), from the start of printing on the path OW of the liquid ejector head 300 to the end of printing, relative to the direction orthogonal to the printing direction PD (Z-axis direction), the supply port P in "Up", outlet P out "Down". In addition, when controlling the orientation of the liquid ejector head 300, the control unit 130 adjusts the orientation so that the arrangement direction of the element 305 is parallel to the direction orthogonal to the printing direction PD (Z-axis direction).

[0085] If the printing of path OW (printing of 1 line) ends, the control unit 130 refers to the head control data to reverse the orientation of the liquid ejector head 300, so that: from the start of printing of the reversing loop HW to the end of printing, relative to the direction orthogonal to the printing direction PD (Z-axis direction), the supply port P in "Down", outlet P out "Up". The method of reversal is the same as described above. Figure 10 , Figure 11 The example shown is similar. In addition, after the printing of the outgoing path OW is completed, the control unit 130 reverses the orientation of the liquid nozzle 300 at the maintenance area MA where the printing of the loop begins.

[0086] In addition, similar to the case of the outgoing path OW, the control unit 130 adjusts the orientation of the liquid ejector head 300 so that the arrangement direction of the element 305 is parallel to the direction orthogonal to the printing direction PD (X-axis direction).

[0087] exist Figure 12 In the illustrated case, the control unit 130 repeatedly reverses the orientation of the liquid ejector head 300 after each line (outbound or inbound) of printing is completed, until all lines of printing on the working surface SF2_B1 of the object B1 are finished. Thus, when the liquid ejector head 300 reciprocates in a roughly horizontal position on the working surface SF2_B1 of the object B1 and performs printing, the control unit 130 controls the orientation of the liquid ejector head 300 so that printing always begins from the positive pressure side (the side with higher pressure) of the liquid circulating inside the liquid ejector head 300. Therefore, the control unit 130 can suppress the occurrence of ejection omissions during printing in a roughly vertical movement position, ensuring the quality of the recorded image.

[0088] Return to Figure 7 The liquid ejection system 1 includes a circulation device 400 with a sensor unit 410. The sensor unit 410 can be connected via... Figure 6The distance sensor 22, posture sensor 23, acceleration sensor 24, and orientation sensor 25 shown are implemented. The sensor unit 410 outputs the detection results to the control unit 100. The detection results of the sensor unit 410 include: the distance between the object B1 (working surface SF1_B1, working surface SF2_B1) being recorded (printed) and the liquid nozzle 300, the posture of the liquid nozzle 300, the acceleration applied to the liquid nozzle 300, and the orientation (direction) of the liquid nozzle 300.

[0089] In addition, the circulation device 400 has Figure 3 The ejector pump 34 and suction pump 35 are shown. The circulation device 400 supplies liquid to the liquid ejector head 300 by controlling the circulation pressure of the liquid circulating between the liquid ejector head 300 and the liquid ejector head 300. Liquid is supplied to the liquid ejector head 300.

[0090] <<Example of processing sequence of control unit>>

[0091] The following uses Figure 13 An example of the processing sequence executed by the control unit 100 in the liquid ejection system 1 will be described. Figure 13 This is a flowchart illustrating an example of the processing sequence performed by the control unit involved in the implementation. Figure 13 The processing sequence shown is implemented by the control unit 130 of the control unit 100.

[0092] like Figure 13 As shown, the control unit 130 reads printing control data and head control data from the storage unit 120 (step S101).

[0093] Furthermore, the control unit 130 determines the positional relationship with the object B1, which is the object to be printed, based on the detection results (distance information) of the sensor unit 410 obtained from the circulation device 400 (step S102).

[0094] Furthermore, based on the printing control data and the positional relationship determined in step S102, the control unit 130 positions the liquid ejector head 300 at the predetermined printing start position (step S103).

[0095] Furthermore, the control unit 130 determines the position and orientation of the liquid nozzle 300 based on the detection results (posture, orientation) of the sensor unit 410 obtained by the circulation device 400 (step S104).

[0096] In addition, the control unit 130 adjusts the orientation of the liquid ejector head 300 so that the positive pressure side (the side with high pressure) of the liquid circulating in the head becomes the printing start side (step S105).

[0097] After adjusting the orientation of the liquid nozzle 300, the control unit 130 performs the printing action and controls it (step S106).

[0098] The control unit 130 determines whether the printing of one line (outbound or inbound) has ended (step S107).

[0099] If the control unit 130 determines that the printing of one line (outbound or inbound) has not been completed (step S107: No), it returns to the processing sequence of step S106 above and continues to control the printing operation.

[0100] On the other hand, if the control unit 130 determines that the printing of one line (going path or loop) has ended (step S107: Yes), it determines whether the printing of all lines has ended (step S108).

[0101] If the control unit 130 determines that printing of all lines has ended (step S108: Yes), it retracts the liquid nozzle 300 to the predetermined retraction position (step S109), and the process ends. Figure 13 The processing order is shown.

[0102] On the other hand, if the control unit 130 determines that the printing of all lines has not been completed (step S108: No), it reverses the orientation of the liquid ejector head 300 (step S110) and returns to the processing sequence of step S106 above to perform the printing action and control.

[0103] <<Variation Examples>>

[0104] (Regarding refresh handling)

[0105] In the above embodiments, a refresh process can also be performed to clean the ejection surface (the surface with the ejection hole 305h) of the liquid ejection head 300 after each line of printing is completed. Figure 14 This is a schematic diagram showing the general structure of the liquid ejection system involved in the modified example.

[0106] like Figure 14 As shown, the liquid spraying system 1 includes a scraper 500. When the orientation of the liquid spray head 300 is reversed, the control unit 100 controls the operation of the scraper 500 to wipe the sprayed surface of the liquid.

[0107] Furthermore, the liquid ejection system 1 can also perform refresh processing by methods other than wiping. For example, the control unit 100 can also perform discard printing (rinsing) while reversing the orientation of the liquid ejection head 300. Alternatively, the control unit 100 can reverse the orientation of the liquid ejection head 300 while performing meniscus oscillation. In addition, the refresh processes described above can also be performed in the aforementioned maintenance area MA.

[0108] The following describes an example of the processing sequence executed by the control unit 100 involved in the modified example. Figure 15 This is a flowchart illustrating an example of the processing sequence performed by the control unit involved in the variation. Figure 15 The processing sequence shown is implemented by the control unit 130 of the control unit 100. Furthermore, the processing sequence executed by the control unit 100 in the modified example has… Figure 15 The processing sequence of step S208 shown is similar to the processing sequence performed by the control unit 100 in the above-described embodiment (see reference). Figure 13 The differences are as follows. The following explains the differences from the embodiments described above.

[0109] like Figure 15 As shown, if the control unit 130 determines that printing of one line (outbound or inbound) has ended (step S207: Yes), the refresh process of the ejection surface of the liquid ejector head 300 is performed (step S208).

[0110] After the refresh process, the control unit 130 determines whether the printing of all lines is finished (step S209) and performs subsequent processing.

[0111] In addition, if the control unit 130 causes the liquid nozzle 300 to oscillate in a meniscus as a refresh process, the refresh process can also be performed after the processing sequence of step S209.

[0112] (Regarding posture during printing)

[0113] In addition to maintaining a generally horizontal posture for printing on a generally horizontal working surface SF1_B1 or a generally vertical working surface SF2_B1 as described in the above embodiments, the liquid ejection system 1 disclosed in this application can also maintain various postures and perform printing depending on the object to be printed. Figure 16 This is a diagram showing the outline of the liquid ejection system involved in the modified example.

[0114] like Figure 16 As shown, in the liquid ejection system 1 of the modified example, the control unit 130 of the control unit 100 can flexibly change the position and posture of the liquid ejection head 300 and eject liquid DP to perform printing, not only for the approximately horizontal working surface SF1_B2 and the approximately vertical working surface SF2_B2, which are the objects to be printed, but also for the curved working surface SF3_B2. In this case, the control unit 130 also controls the position and posture of the liquid ejection head 300 so that printing starts from the positive pressure side (the side with high pressure) of the liquid circulating inside the liquid ejection head 300.

[0115] In the above embodiments and modifications, an example is described where the liquid ejection system 1 includes a robotic arm, and the control unit 100 controls the position and orientation of the liquid ejection head 300 mounted at the foremost end of the robotic arm 200 via the robotic arm 200. The control of the liquid ejection system 1 described in the above embodiments and modifications can be applied not only to inkjet printers and inkjet plotters using inkjet recording methods, but also to various devices that eject liquids (or droplets) using inkjet methods. In this case, various devices such as inkjet printers using inkjet recording methods can have a mechanism that reverses the orientation of the liquid ejection head 30 after each line of printing. Furthermore, while reversing the orientation of the liquid ejection head 30 after each line of printing is illustrated, it is not necessarily limited to this. For example, the control unit 100 can also reverse the circulation direction of the liquid flowing through the liquid ejection head 30 after each line of printing is completed. Specifically, after the printing of the outgoing path OW is completed, the control unit 100 can control the circulation pressure to change from positive pressure to negative pressure. Therefore, printing begins on the positive pressure side (the side with higher pressure) of the liquid circulating inside the liquid nozzle 300.

[0116] Characteristic embodiments have been described in order to fully and clearly disclose the technology covered by the claims. However, the claims should not be limited to the above-described embodiments, but should be embodied through all modifications and alternative structures that can be created by those skilled in the art within the scope of the basic matters disclosed in this specification.

[0117] Symbol Explanation

[0118] 1. Liquid ejection system

[0119] 5 abutment

[0120] 10 Controllers

[0121] 11 Signal Processing Circuit

[0122] 12 CPU

[0123] 13 DRAM

[0124] 14 Flash ROM

[0125] 15 USB connectors

[0126] 16. Wireless Communications Department

[0127] 17 Internal Bus

[0128] 21 cameras

[0129] 22 Distance Sensor

[0130] 23. Posture sensor

[0131] 24 Accelerometers

[0132] 25 Azimuth Sensor

[0133] 31. Movable parts

[0134] 32 Actuators

[0135] 33 Encoder

[0136] 34. Ejection Pump

[0137] 35 Suction Pump

[0138] 100 Control Unit

[0139] 110 Input / Output IF

[0140] 120 Storage Department

[0141] 121 Data storage unit for printing control

[0142] 122-head control data storage unit

[0143] 130 Control Department

[0144] 200 robotic arms

[0145] 300 Liquid Injector Head

[0146] 301 Supply Reservoir

[0147] 302 Supply Manifold

[0148] 303 Recycling Manifold

[0149] 304 recovery reservoir

[0150] 305 components

[0151] 400 Circulation Device

[0152] 410 Sensors Section.

Claims

1. A recording device comprising: The liquid ejection section is capable of rotating around a predetermined axis, allowing the liquid to circulate internally and be ejected; and The control unit controls the operation of the liquid ejection unit to cause it to reciprocate along the printing direction and eject liquid. The liquid ejection section includes: Multiple elements, each with a jet nozzle for ejecting liquid; The supply manifold delivers liquid to the plurality of components; and The supply reservoir delivers liquid to the supply manifold. The control unit controls the position and orientation of the liquid ejection section so that printing begins from the side where the plurality of elements are arranged on the side of the supply reservoir where the pressure is high.

2. The recording device according to claim 1, wherein, The control unit controls the liquid ejection section to maintain a roughly horizontal posture relative to the working surface of the object being printed.

3. The recording device according to claim 2, wherein, Whenever the reciprocating path or loop ends, the control unit reverses the orientation of the liquid ejection section.

4. The recording device according to claim 3, wherein, The control unit moves the liquid ejection section in an arc shape, thereby reversing the orientation of the liquid ejection section.

5. The recording device according to claim 3, wherein, The control unit rotates the liquid ejection section, thereby reversing the orientation of the liquid ejection section.

6. The recording apparatus according to any one of claims 3 to 5, wherein, The control unit refreshes the liquid ejection surface when it reverses the orientation of the liquid ejection section.

7. The recording device according to claim 6, wherein, The recording device also includes a wiping mechanism for wiping the ejection surface. The control unit wipes the liquid ejection surface when it reverses the orientation of the liquid ejection part.

8. The recording device according to claim 6, wherein, The control unit performs discard printing when it reverses the orientation of the liquid ejection section.

9. The recording device according to claim 6, wherein, The control unit causes the liquid ejection section to oscillate in a meniscus shape and reverses the orientation of the liquid ejection section.

10. The recording device according to claim 1, wherein, The liquid ejection section has: A supply port for supplying liquid to the interior; and the outlet for draining liquid from the inside, The position and orientation of the liquid ejector are controlled so that printing begins on the side of the element that is positioned upstream of the liquid circulating from the supply port to the discharge port.

11. A recording device comprising: The liquid ejection section circulates the liquid internally and ejects the liquid. A robotic arm causes the liquid ejection section to reciprocate along the printing direction; and The control unit controls the movement of the liquid ejection unit via the robotic arm, causing it to reciprocate along the printing direction and eject liquid. The liquid ejection section includes: Multiple elements, each with a jet nozzle for ejecting liquid; A supply manifold is used to deliver liquid to the plurality of components; and The supply reservoir delivers liquid to the supply manifold. The control unit controls the liquid ejection unit or the robotic arm to start printing from the side where the plurality of elements are arranged on the side of the supply reservoir where the pressure is high.

Images