JP2007290366A - Liquid droplet transporting device, valve, memory apparatus, and display apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a liquid channel structure which can surely prevent staying of bubbles in a channel, and to provide a liquid droplet jet apparatus. <P>SOLUTION: An ink channel in a channel unit includes a pressure chamber 16 and a throttle channel 20 in which an ink flows along mutually different planes, and a communication hole 18 which makes the pressure chamber 16 and the throttle channel 20 communicate with each other. A center line C3 of the communication hole 18 deviates from a center line C1 of the pressure chamber 16 in a width direction of the pressure chamber 16. Moreover, the center line C3 of the communication hole 18 deviates also from a center line C2 of the throttle channel 20 in a width direction of the throttle channel 20. Consequently, a swirling current is generated at connection parts 16a and 20a to the pressure chamber 16 and the communication hole 18 of the throttle channel 20, so that staying of the bubbles is prevented. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a droplet transfer device, a valve, a storage device, and a display device that transfer droplets using an electrowetting phenomenon.

Conventionally, a technique for transferring droplets using a phenomenon (electrowetting phenomenon) in which liquid repellency (wetting angle) on the surface of an insulating layer changes when a potential difference occurs on both sides of the insulating layer is known. ing. For example, a microdroplet transport device described in Patent Document 1 (Japanese Patent Application Laid-Open No. 2005-25769) includes two electrodes (a first electrode and a second electrode) provided on the surface of a substrate, A dielectric film covering the first electrode, and a hydrophobic film (insulating layer) covering the dielectric film and the second electrode over the entire surface are provided. In this droplet transport device, when a voltage is applied between the two electrodes in a state where the droplet is disposed between both electrodes in contact with both of the arrangement regions of the two electrodes, a dielectric film is provided. The wetting angle of the hydrophobic film surface in the first electrode arrangement region is lower than the wetting angle of the hydrophobic film surface in the second electrode arrangement region where the dielectric film is not provided. Therefore, the difference in the wetting angle becomes a driving force, and the droplet is transferred in one direction from the second electrode toward the first electrode.
JP 2005-25769 A

  The microdroplet transport device described in Patent Document 1 moves a droplet from one electrode to the other electrode in one direction. On the other hand, in addition to such an apparatus, an apparatus for transferring a minute droplet between two electrode arrangement regions is also desired in various fields. In that case, if it is possible to detect in which of the two electrode arrangement regions the droplets are present, the utility value of the device becomes even higher.

  An object of the present invention is to transfer a droplet between two regions using an electrowetting phenomenon, and to detect in which of the two regions a droplet is present. It is to provide a droplet transfer device.

Means for Solving the Problems and Effects of the Invention

  In addition, the code | symbol with the parenthesis attached | subjected to each element shown below is only the illustration of the element, and does not limit each element.

  According to the first aspect of the present invention, the first electrode (22) disposed on the surface (10b) of the substrate (10a) and the first electrode on the surface of the substrate in the vicinity of the first electrode. The second electrode (23) arranged at a predetermined distance, the first electrode, and the second electrode are arranged so as to cover the first electrode and the second electrode, respectively, and the conductive droplet (21) present on the surface of the second electrode (23) and the electrode (22) Or a second layer that detects the presence of droplets on the second electrode in cooperation with the second electrode and the insulating layer (24) whose liquid repellency changes on the surface in accordance with the potential difference with the second electrode 23a). A droplet transfer device (20) comprising three electrodes (23b) is provided.

  According to the droplet transfer device of the present invention, the liquid repellency (wetting angle) on the surface of the insulating layer covering these electrodes can be changed by changing the potentials of the first electrode and the second electrode. Accordingly, it is possible to transfer the liquid droplet from the high liquid repellency region to the low region between the first electrode arrangement region and the second electrode arrangement region. That is, a simple configuration including two electrodes and an insulating layer enables droplet transfer between the two regions. In the present invention, the “arrangement region of the first electrode” means a region overlapping the first electrode in the insulating layer, and the “arrangement region of the second electrode” overlaps the second electrode in the insulating layer. Means an area.

  Furthermore, since the third electrode that detects the presence of the droplet on the second electrode in cooperation with the second electrode is provided, when there is a conductive droplet on the second electrode, A predetermined capacitance between the two electrodes and the third electrode can be detected. On the other hand, when there is no liquid droplet on the second electrode, only a detection value in which the capacitance between the second electrode and the third electrode is less than a predetermined value can be obtained. Therefore, it is possible to determine whether or not a droplet exists on the second electrode by detecting the capacitance between the second electrode and the third electrode. As a result, it is possible to determine in which arrangement region of the first electrode and the second electrode the droplet is present.

  In the droplet transfer device (20) according to the present invention, at least one of the first electrode (22) and the second electrode (23) is arranged apart from each other on the surface (10b) of the substrate (10a). Alternatively, it may be divided as at least two divided electrodes (23a, 23b). In this case, when there are conductive droplets on the two divided electrodes, a predetermined capacitance between the two divided electrodes can be detected. On the other hand, when there are no droplets on the two divided electrodes, the capacitance between the two divided electrodes decreases. Therefore, whether or not a droplet exists on the two divided electrodes can be determined based on whether or not the capacitance between the two divided electrodes can be detected. In this case, one of the divided electrodes may be the third electrode (23b).

  The droplet transfer device (20) of the present invention may further include a potential applying mechanism (25) that applies a potential to the first electrode (22) and the second electrode (23), respectively. By applying different potentials to the first electrode and the second electrode, the liquid repellency on the surface of the insulating layer (24) of the part covering one electrode is lowered as compared with the part covering the other electrode, The droplets may be transferred between the insulating layers covering the first electrode and the second electrode, respectively. In this case, by applying different potentials to the first electrode and the second electrode, the liquid repellency at the surface of the insulating layer covering one electrode is made lower than that covering the other electrode. The liquid droplets can be transferred between the arrangement area of the first electrode and the arrangement area of the second electrode.

  In the droplet transfer device (20) of the present invention, the divided electrodes (23a, 23b) may be configured such that when the droplet (21) is transferred to a region where the divided electrode is disposed, the droplet is divided. The liquid droplets may be disposed between the electrodes while being in contact with each other, and based on the capacitance between the divided electrodes, the liquid droplets are formed in the second region and the second region. You may further provide the droplet position detector (26) which detects in which area | region where the electrode is arrange | positioned. In this case, when a conductive droplet is in contact with both of the two divided electrodes and exists between them, an insulating layer is sandwiched between the two divided electrodes and the droplet, respectively. However, this capacitance is reduced in the absence of droplets. Therefore, by detecting the capacitance between the two divided electrodes, it is possible to detect in which arrangement region of the first electrode and the second electrode a droplet is present.

  In the droplet transfer device (20) of the present invention, the ground electrode (27) can be disposed on the surface (24c) of the insulating layer (24) covering the first electrode (22) and the second electrode (23), respectively. . In this case, the liquid droplet is kept in contact with the ground electrode and held at a predetermined potential, so that the potential difference between the electrode and the liquid droplet is stabilized. Therefore, the droplet transfer operation can be performed reliably.

  In the droplet transfer device (20) of the present invention, the third electrode (124) may extend away from the surface (10b) of the substrate (10a) and face the second electrode (123). By disposing the third electrode in this way, the electrostatic capacitance between the second electrode and the third electrode can be detected when a droplet is present on the second electrode. On the other hand, when no droplet is present on the second electrode, the detected capacitance decreases. Therefore, by measuring the capacitance, it is possible to determine in which arrangement region of the first electrode and the second electrode the droplet is present.

  In the droplet transfer device (20) of the present invention, the third electrode (224) extends so as to face a part of the first electrode (22) and the second electrode (123) and is installed as a ground electrode. obtain. In this case, regardless of whether the droplet is present on the first electrode or the second electrode, the droplet contacts the third electrode and is always held at a predetermined potential. Therefore, since the potential difference between the electrode and the droplet is stabilized, the droplet transfer operation can be performed reliably. Further, when a droplet is present on the second electrode, the capacitance between the second electrode and the third electrode can be detected. On the other hand, when there is no liquid droplet on the second electrode, a predetermined capacitance cannot be detected. Therefore, by measuring the capacitance, it is possible to determine in which arrangement region of the first electrode and the second electrode the droplet is present.

  In the droplet transfer device (20) of the present invention, the insulating layer (24) is always provided in a region outside the first electrode (22) and the second electrode (23) on the surface (10b) of the substrate (10a). The first liquid repellent film (40) having a liquid repellency higher than the liquid repellency of) may be formed. In this case, it is possible to prevent the droplet from moving unexpectedly outside the range of the electrode due to the vibration of the droplet. Note that the liquid repellency of the region outside the first electrode and the second electrode may be equal to or higher than the liquid repellency of the insulating layer. In this case, the insulating layer itself covering the first electrode and the second electrode may further extend to the outside of the first electrode and the second electrode to form the first liquid repellent film, or the first electrode and the second electrode A first liquid repellent film different from the insulating layer may be formed outside the electrode.

  In the droplet transfer device (20) of the present invention, the width of the region where the first liquid repellent film (40) is not formed between the first electrode (22) and the second electrode (23) is locally narrowed. It may be. In this case, it is possible to prevent the droplet from unexpectedly moving to the opposite electrode due to the vibration of the droplet.

  In the droplet transfer device (20) of the present invention, the insulating layer (24) is always provided in a region between the first electrode (22) and the second electrode (23) on the surface (10b) of the substrate (10a). The second liquid repellent film (41) having a liquid repellency higher than the liquid repellency of) may be formed. In this case, it is possible to prevent the droplet from unexpectedly moving to the opposite electrode due to the vibration of the droplet. Note that the liquid repellency of the region between the first electrode and the second electrode may be higher than that of the insulating layer, and the insulating layer covering the first electrode and the second electrode is the first electrode and the second electrode. The second liquid repellent film may be formed between the first electrode and the second electrode, or a second liquid repellent film different from the insulating layer may be formed between the first electrode and the second electrode.

  In the droplet transfer device (20) of the present invention, a part of the second liquid repellent film (41) protrudes into a region where the first electrode (22) and the second electrode (23) are respectively disposed. Also good. In this case, it is possible to smoothly transfer the droplet between the two electrode arrangement regions while preventing the droplet from unexpectedly moving to the opposite electrode due to the vibration of the droplet.

  The droplet transfer device (20) of the present invention may be provided in the valve (11). In the valve including the droplet transfer device of the present invention, the base material (10a) may be formed with a fluid passageway (19) that opens in a region where the first electrode (22) is disposed. When the droplet (21) is present in a region where one electrode is disposed, the fluid passage opening (19a) may be closed by the droplet, and the second electrode (23) is disposed in the region where the second electrode (23) is disposed. The opening of the fluid passage may be opened when a droplet is present. In this case, the opening of the fluid passage can be closed by transferring the droplet to the arrangement region of the first electrode, and the opening of the fluid passage can be opened by transferring the droplet to the arrangement region of the second electrode. That is, since the valve includes a droplet transfer device having a simple configuration including two electrodes and an insulating layer, the fluid passage can be opened and closed.

  The valve (11) provided with the droplet transfer device (20) of the present invention includes an ink containing space (12) for containing ink (I) and an air communication path (19) for communicating the ink containing space with the atmosphere. And opening and closing the atmosphere communication path by transferring the droplet (21) between the first electrode (22) and the second electrode (23). May be. In this case, when the ink is not supplied from the ink cartridge to the supply destination, the droplet is transferred to the first electrode to close the atmosphere communication path, and only when the ink is supplied, the droplet is transferred to the second electrode to be connected to the atmosphere connection. Open the passage. That is to say, the ink droplet drying device (thickening) can be effectively prevented without causing a shortage of ink supply by the droplet transfer device having a simple configuration.

  A valve (11) having a droplet transfer device (20) of the present invention is a cap (1a) for covering an ink ejection surface (1a) of an inkjet head (1) that ejects ink (I) to a recording medium (P). 60), and a space (64) formed by the ink ejection surface and the cap, and a communication path (65) that communicates with the outside of the cap, may be provided in the cap. 21) may be opened and closed by transferring between the first electrode (22) and the second electrode (23). In a state where the cap is mounted on the ink ejection surface of the inkjet head, the droplets are positioned on the first electrode, whereby the communication path of the cap can be closed to prevent the ink from drying. On the other hand, when the cap is attached to or detached from the ink ejection surface, the droplets are transferred to the second electrode to open the communication path, thereby preventing the meniscus destruction of the nozzle due to the pressure variation in the space in the cap during mounting . In this manner, ink drying and meniscus destruction can be prevented by a droplet transfer device having a simple configuration.

  The droplet transfer device (20) of the present invention may be provided in the storage device (70). In the storage device provided with the droplet transfer device of the present invention, the droplet transfer device transfers the droplet (21) to the first electrode (22) and the second electrode (23) according to data stored in the storage device. ). In this case, the droplet can be transferred to either the first electrode arrangement region or the second electrode arrangement region in accordance with the data stored in the storage device. That is, since the storage device includes a droplet transfer device having a simple configuration, 1-bit data can be stored. In addition, since it is possible to detect in which arrangement region of the first electrode and the second electrode a droplet is present, it is possible to determine and read out stored data. Further, since the memory device of the present invention does not necessarily require a silicon substrate used in a normal semiconductor memory device, it can be manufactured at a lower cost by using a substrate made of a synthetic resin, for example.

  A droplet transfer device (20) according to the present invention and a transmission hole (83a) which is disposed to face the surface (81a) of the substrate (81) and which is formed at a position corresponding to the first electrode (22). In the display device (80) including the cover plate (83) having the liquid crystal, the droplet (21) may be colored, and the droplet transfer device is configured to perform the display according to the data to be displayed on the display device. The droplet may be transferred between the first electrode and the second electrode (23). In this case, when the colored droplet is transferred to the position of the first electrode, the color of the droplet is displayed through the cover plate. On the other hand, when the droplet is transferred to the position of the second electrode, it is blocked by the cover plate and the color of the droplet is not displayed. Therefore, desired characters, images, and the like can be displayed by a droplet transfer device having a simple configuration. In addition, in the display device using the droplet transfer device of the present invention, the droplets are positioned on the first electrode or the second electrode as long as the potential applied to the first electrode is not different from the potential applied to the second electrode. Does not move from position. That is, it is not necessary to always supply power in order to maintain the same display state. Therefore, the same display state can be maintained without consuming power.

  In the display device (80) provided with the droplet transfer device (20) of the present invention, the droplet (21) may be colored, and the first electrode (22) and the substrate corresponding to the first electrode The portion of (81) and the portion of the insulating layer (24) corresponding to the first electrode may be all transparent, the second electrode (23), the portion of the base material corresponding to the second electrode, In addition, at least one of the portions of the insulating layer corresponding to the second electrode may be impermeable. In this case, since the first electrode and the corresponding base material and insulating layer are all transparent, the color of the droplet is displayed when the colored droplet is transferred to the arrangement area of the first electrode. . On the other hand, since at least one of the second electrode, the base material and the insulating layer corresponding to the second electrode has non-transmissibility (property of transmitting light), the colored droplets were transferred to the arrangement area of the second electrode. Sometimes, the color of the droplet is not displayed when viewed from the surface of the substrate opposite to the electrode. Therefore, a desired character, an image, or the like can be displayed by transferring the colored droplet between the position of the first electrode and the position of the second electrode.

  According to the second aspect of the present invention, the base material (10a) is a valve (11) having a fluid passageway (19) opened on the surface (10b) thereof, and the fluid on the surface of the base material. A first electrode (22) disposed in a region including the opening (19a) of the passage, and a second electrode (23 disposed at a predetermined distance from the first electrode in the vicinity of the first electrode on the surface of the base material. ) And the first electrode and the second electrode, respectively, and the liquid repellency on the surface depends on the potential difference between the conductive droplet (21) present on the surface and the electrode. An insulating layer (24) that changes, and the droplet is transferred to the region where the first electrode is disposed to close the opening of the fluid passage, and the droplet is disposed in the region where the second electrode is disposed. By opening the fluid passage opening That the valve is provided.

  According to the valve of the present invention, the first electrode and the second electrode are changed in potential to change the liquid repellency (wetting angle) on the surface of the insulating layer covering these electrodes. The droplet is transferred between the region and the region where the second electrode is disposed. Then, the opening of the fluid passage is closed by transferring the droplet to the arrangement region of the first electrode, while the opening of the fluid passage is opened by transferring the droplet to the arrangement region of the second electrode. That is, the fluid passage can be opened and closed with a simple configuration including two electrodes and an insulating layer.

  According to the present invention, an ink cartridge (5) provided with the valve (11) of the present invention is provided. In this case, the air communication hole of the ink cartridge can be opened and closed by the valve of the present invention. Therefore, it is possible to effectively prevent the ink from being dried by closing the air communication hole when the ink is not supplied from the ink cartridge to the supply destination and opening the ink communication when the ink is supplied.

  A first embodiment of the present invention will be described. The first embodiment is an example in which the present invention is applied to an air communication hole opening / closing valve of an ink cartridge.

  First, the ink jet printer 100 to which the ink cartridge 5 is mounted will be briefly described. As shown in FIG. 1, an inkjet printer 100 includes a carriage 2 that can move in the left-right direction in FIG. 1, a serial type inkjet head 1 that is provided on the carriage 2 and that ejects ink onto recording paper P, A conveyance roller 3 that conveys the recording paper P forward in FIG. 1 and a control device 4 (see FIG. 4) that controls each part of the printer 100 are provided.

  The inkjet head 1 is connected to an ink cartridge 5 that stores ink via a tube 6. The ink-jet head 1 moves in the left-right direction integrally with the carriage 2 and ejects ink onto the recording paper P from nozzles (not shown) arranged on the lower surface thereof to obtain desired characters, images, etc. Record. Further, the recording paper P on which an image or the like is recorded by the inkjet head 1 is discharged forward by the transport roller 3.

  Next, the ink cartridge 5 will be described. As shown in FIG. 2, the ink cartridge 5 includes a cartridge body 10 having an ink storage space 12 and a valve 11 that opens and closes an air communication hole 19 that communicates the ink storage space 12 with the atmosphere.

  The cartridge body 10 is formed in a rectangular parallelepiped shape with a synthetic resin material (for example, polypropylene) having excellent ink wettability. In addition, an ink storage space 12 for storing the ink I and an air introduction path 13 communicating with the upper portion of the ink storage space 12 are formed inside the cartridge body 10. More specifically, the ink containing space 12 and the air introduction path 13 are separated by a partition wall 14 extending from the bottom surface of the cartridge body 10 to the vicinity of the ceiling surface, and between the upper end of the partition wall 14 and the ceiling surface of the cartridge body 10. The gap 15 is communicated.

  The ink storage space 12 communicates with an ink supply hole 16 formed in the bottom wall 10a of the cartridge body 10 so as to penetrate therethrough. The ink supply hole 16 is connected to an ink supply pipe 18 of the ink jet printer 100 through a seal member 17. That is, the ink I in the ink storage space 12 is supplied to the inkjet head 1 through the ink supply hole 16 and the ink supply pipe 18.

  The atmosphere introduction path 13 communicates with an atmosphere communication hole 19 (fluid path, atmosphere communication path) that penetrates the bottom wall 10 a of the cartridge body 10. Therefore, when the ink I in the ink storage space 12 is discharged (supplied to the inkjet head 1), the air is introduced into the upper portion of the ink storage space 12 through the air communication hole 19 and the air introduction path 13. . The air communication hole 19 is provided by the valve 11 only when the ink jet printer 100 is used (when the ink jet head 1 is ejected) in order to prevent the ink I in the ink containing space 12 from being dried and thickened as much as possible. Opened, otherwise closed. This will be described in detail later together with the description of the next valve 11.

  Next, the valve 11 will be described. The valve 11 has a position 2 on the inner surface (upper surface) of the bottom wall 10a of the cartridge body 10 that overlaps the upper end opening 19a of the atmosphere communication hole 19 (closes the opening 19a) and a position shifted from the upper end opening 19a. A droplet transfer unit 20 (droplet transfer device) that transfers the conductive droplet 21 between two positions is provided. And the droplet transfer part 20 is comprised so that the opening-and-closing state of the atmospheric | air communication hole 19 may be switched by transferring the droplet 21 between two positions. Further, a protection unit 28 is provided above the droplet transfer unit 20 to prevent ink mist from directly falling on the conductive droplet 21.

  Here, as the conductive droplet 21, for example, a droplet 21 such as water or an aqueous solution obtained by dissolving glycerin or the like in water can be used. Or the ionic liquid (room temperature molten salt) which consists only of ions can also be used. Since this ionic liquid is generally non-volatile, there is an advantage that it is difficult to evaporate even if it is exposed to the atmosphere for a long time.

  As shown in FIGS. 3A and 3B, the droplet transfer unit 20 has an upper end opening 19a of the air communication hole 19 on the upper surface of the bottom wall 10a (base material) of the cartridge body 10 made of a synthetic resin material. The first electrode 22 disposed in the region including the first electrode 22, the second electrode 23 disposed on the upper surface of the bottom wall 10a as well as the first electrode 22 at a predetermined interval in the vicinity of the first electrode 22, and the bottom wall 10a The insulating layer 24 is formed so as to completely cover both the first electrode 22 and the second electrode 23 on the upper surface.

  The first electrode 22 has a substantially square planar shape. Further, the upper end opening 19 a of the air communication hole 19 is located substantially at the center of the first electrode 22 in plan view. Therefore, when the droplet 21 exists in the arrangement region of the first electrode 22, the atmosphere communication hole 19 is surely closed by the droplet 21 (see FIGS. 6A and 6B). . In the present invention, the “arrangement region of the first electrode” means a region overlapping the first electrode in the insulating layer. In the present embodiment, the length of one side of the first electrode 22 is about 1 to 2 mm, and the diameter of the upper end opening 19a is about 0.3 mm. In addition, it is preferable that the wetting angle of the inner surface of the atmospheric communication hole 19 is 90 degrees or more so that the droplet 21 does not flow into the atmospheric communication hole 19.

  Similarly to the first electrode 22, the second electrode 23 has a substantially square planar shape, and is arranged at a predetermined interval on the right side of the first electrode 22 in FIG. Further, the second electrode 23 is divided into two divided electrodes 23a (second electrode) and 23b (third electrode) having the same shape and spaced apart from each other. These two divided electrodes 23 a and 23 b are arranged symmetrically with respect to a straight line L passing through the center of gravity of the first electrode 22 and the center of gravity of the second electrode 23. The two divided electrodes 23a and 23b may be disposed in the same direction as the first electrode 22 and the second electrode 23 as shown in FIGS. 26 (a) and 26 (b). . That is, the second electrode 23 may be divided in a direction orthogonal to the direction in which the first electrode 22 and the second electrode 23 are arranged. In the present embodiment, the length of one side of the second electrode 23 is about 1 to 2 mm.

  When the ink cartridge 5 is attached to the ink jet printer 100, the two divided electrodes 23a and 23b of the first electrode 22 and the second electrode 23 are connected to the potential applying unit 25 (potential applying portion) provided in the ink jet printer 100. A predetermined potential is applied to the electrodes 22 and 23 (23a and 23b) from the potential applying unit 25, respectively. However, the potential applying unit 25 simultaneously applies the same potential to the two divided electrodes 23 a and 23 b constituting the second electrode 23.

  The insulating layer 24 is a thin film having a relatively high liquid repellency made of fluorine resin, polyimide resin, epoxy resin, or the like. The insulating layer 24 is formed on the entire surface of a predetermined area including the arrangement area of the first electrode 22 and the arrangement area of the second electrode 23 on the inner surface of the bottom wall 10 a of the cartridge body 10. That is, as shown in FIGS. 3A and 3B, the insulating layer 24 includes the first electrode 22 and the second electrode in addition to the arrangement region of the first electrode 22 and the arrangement region of the second electrode 23. 23 is also formed in a region 24a outside the first electrode (first liquid repellent film), and is also formed in a region 24b between the first electrode 22 and the second electrode 23 (second liquid repellent film). In the present invention, the “second electrode arrangement region” means a region of the insulating layer overlapping the second electrode.

  When a potential difference occurs between the droplet 21 and the electrode (the first electrode 22 or the second electrode 23) in a state where the conductive droplet 21 exists on the surface of the insulating layer 24, the potential difference is large. The liquid repellency (wetting angle) on the surface of the insulating layer 24 is lowered (electrowetting phenomenon).

  Therefore, the potential applying unit 25 is configured to apply different potentials to the first electrode 22 and the second electrode 23 based on a command from the control device 4 (valve control unit 31) of the printer 100. In addition, by making the liquid repellency of the insulating layer 24 different between the arrangement region of the first electrode 22 and the arrangement region of the second electrode 23, the droplet 21 is transferred between the two regions.

  More specifically, the potential applying unit 25 applies a predetermined potential that is not a ground potential to one of the first electrode 22 and the second electrode 23 and applies a ground potential to the other. Then, the liquid repellency at the surface of the portion of the insulating layer 24 covering one electrode to which the predetermined potential is applied is lower than the portion covering the other electrode to which the ground potential is applied, and from the arrangement region of the other electrode The droplet 21 moves to the arrangement area of one electrode.

  As shown in FIGS. 3A and 3B, two ground electrodes 27 are disposed on the insulating layer 24 covering the first electrode 22 and the second electrode 23, respectively. The ground electrode 27 is always held at the ground potential. Since the droplet 21 existing in the arrangement region of the first electrode 22 or the arrangement region of the second electrode 23 contacts the ground electrode 27, the potential of the droplet 21 is held at the ground potential and fluctuates. There is nothing.

  Incidentally, the two divided electrodes 23a and 23b of the second electrode 23 are connected to a droplet position detector 26 (droplet position detector) shown in FIG. The droplet position detection unit 26 detects the capacitance between the two divided electrodes 23a and 23b. As shown in FIG. 3A, the two divided electrodes 23 a and 23 b are arranged symmetrically with respect to a straight line L passing through the center of gravity of the first electrode 22 and the center of gravity of the second electrode 23. In this case, when the droplet 21 is transferred from the arrangement region of the first electrode 22 to the arrangement region of the second electrode 23, the droplet 21 is positioned so as to straddle the two divided electrodes 23a and 23b. The two divided electrodes 23a and 23b are in contact with each other while being in contact (see FIGS. 9A and 9B). At this time, one capacitor is constituted by the divided electrode, the conductive droplet 21 and the insulating layer 24 (dielectric) sandwiched between them. That is, a system composed of the two divided electrodes 23a and 23b, the insulating layer 24, and the droplet 21 can be represented by a circuit composed of two capacitors C1 and C2 connected in series as shown in FIG.

  That is, when the droplet 21 exists in the arrangement region of the second electrode 23, the droplet position detector 26 causes the capacitances of the capacitors C1 and C2 between the two divided electrodes 23a and 23b (for example, fluorine-based). When the thickness of the insulating layer 24 made of resin is 0.5 μm, about 40 nF) is detected. On the other hand, when the droplet 21 is not in the arrangement region of the second electrode 23 (when it is located in the arrangement region of the first electrode 22), compared to the case where the droplet 21 is located in the arrangement region of the second electrode 23. The electrostatic capacitance detected by the droplet position detection unit 26 decreases or becomes zero depending on the distance between the two divided electrodes 23a and 23b.

  Therefore, in the present embodiment, the droplet position detection unit 26 applies the droplet to any region of the first electrode 22 and the second electrode 23 based on the detected capacitance between the two divided electrodes 23a and 23b. 21 is configured to be detected. More specifically, the droplet position detection unit 26 indicates that the droplet 21 is present in the arrangement region of the second electrode 23 when the detected capacitance value is greater than or equal to a predetermined value, and the atmosphere It is determined that the communication hole 19 is open. On the other hand, when the detected capacitance value is less than a predetermined value (for example, a value close to 0), the droplet 21 is not present in the arrangement region of the second electrode 23 (the first electrode 22 has It is determined that the atmospheric communication hole 19 is closed. That is, the two divided electrodes function as a sensor that cooperates to detect the presence of a droplet.

  Next, the droplet transfer operation of the droplet transfer unit 20 will be described with reference to FIGS. 6 (a) to 10 (b). In FIGS. 6A to 10B, “+” indicates that a predetermined potential is applied to the electrode, and “GND” indicates that a ground potential is applied.

  As shown in FIGS. 6A and 6B, in the state where the droplet 21 exists in the arrangement region of the first electrode 22, the atmosphere communication hole 19 is closed and closed by the droplet 21. Yes. The first electrode 22 and the second electrode 23 (the two divided electrodes 23a and 23b) are each provided with a ground potential, and the droplet 21 has a high wetting angle. It is within the placement area. The droplet 21 is in contact with the ground electrode 27 and is held at the ground potential. In addition, the diameter of the droplet 21 should just be a magnitude | size which does not protrude from the 1st electrode 22 and the 2nd electrode 23, and is about 1-2 mm in this embodiment.

  When the droplet 21 is transferred from the state shown in FIGS. 6A and 6B to the region where the second electrode 23 is disposed, first, as shown in FIGS. A predetermined potential is applied to the first electrode 22 by the applying unit 25. Then, since a potential difference is generated between the first electrode 22 to which a predetermined potential is applied and the droplet 21 held at the ground potential, the liquid repellency (droplet 21) of the insulating layer 24 in the region where the first electrode 22 is disposed. The wetting angle of the first electrode 22 and the second electrode 23, and the liquid droplet 21 spreads between the first electrode 22 and the second electrode 23.

  Next, as shown in FIGS. 8A and 8B, the potential applying unit 25 switches the potential of the first electrode 22 from the predetermined potential to the ground potential, and at the same time, the potential of the second electrode 23 is changed to the ground. The potential is switched to a predetermined potential. Then, the liquid repellency of the insulating layer 24 in the arrangement region of the first electrode 22 is increased, and at the same time, the liquid repellency of the insulating layer 24 in the arrangement region of the second electrode 23 is lowered. Therefore, the droplet 21 that has spread from the region where the first electrode 22 is disposed to the region where the second electrode 23 is disposed moves toward the second electrode 23 having a low liquid repellency. ), 9 (b), the air communication hole 19 is opened.

  When the droplet 21 completely moves to the arrangement area of the second electrode 23, as shown in FIGS. 10 (a) and 10 (b), the potential applying unit 25 changes the potential of the second electrode 23 from a predetermined potential. Switched to ground potential. Then, the liquid repellency of the arrangement region of the second electrode 23 is increased, the wetting angle of the droplet 21 is increased, and the droplet 21 is within the arrangement region of the second electrode 23.

  On the contrary, as shown in FIGS. 10A and 10B, from the state where the droplet 21 exists in the arrangement region of the second electrode 23 and the air communication hole 19 is opened, the potential applying unit 25, when a predetermined potential is applied to the first electrode 22 and at the same time a ground potential is applied to the second electrode 23, the droplet 21 moves from the region where the second electrode 23 is disposed to the region where the first electrode 22 is disposed. As shown in FIGS. 6A and 6B, the atmospheric communication hole 19 is closed by the droplet 21.

  Next, the electrical configuration of the ink jet printer 100 centering on the control device 4 will be described with reference to the block diagram of FIG. The control device 4 is processed by a CPU (Central Processing Unit) which is a central processing unit, a ROM (Read Only Memory) storing a program and data for controlling each part of the inkjet printer 100, and the CPU. A RAM (Random Access Memory) or the like for temporarily storing data is provided. As shown in FIG. 4, the control device 4 includes a head control unit 30 that controls the ink ejection operation of the inkjet head 1 and a valve control unit 31 that controls the opening / closing operation of the valve 11.

  The head control unit 30 controls the inkjet head 1 based on the print data input from the PC 33 to eject ink onto the recording paper P, thereby recording predetermined characters, images, and the like on the recording paper P.

  The valve control unit 31 controls the opening / closing operation of the valve 11 so that the air communication hole 19 is opened only when the ink jetting operation of the inkjet head 1 is performed and the air communication hole 19 is closed otherwise. .

  More specifically, as shown in FIG. 11, when the air communication hole 19 is closed and the valve control unit 31 receives a print command from the PC 33, the ink jet operation of the inkjet head 1 is performed. Before being performed, a signal for opening the air communication hole 19 is output to the potential applying unit 25. At this time, the potential applying unit 25 applies a ground potential to the first electrode 22 and applies a predetermined potential to the second electrode 23. Then, as shown in FIG. 12, the droplet 21 is transferred from the first electrode 22 to the second electrode 23, and the atmosphere communication hole 19 is opened.

  Further, when the recording on the recording paper P is completed, the valve control unit 31 outputs a signal for closing the atmospheric communication hole 19 to the potential applying unit 25. At this time, the potential applying unit 25 applies a predetermined potential to the first electrode 22 and applies a ground potential to the second electrode 23. Then, as shown in FIG. 11, the droplet 21 is transferred from the second electrode 23 to the first electrode 22, and the atmosphere communication hole 19 is closed by the droplet 21. Thus, the valve 11 opens the air communication hole 19 only when ink is ejected from the inkjet head 1. Accordingly, it is possible to effectively prevent ink drying (thickening) without causing insufficient supply of the ink I to the inkjet head 1.

  Further, as described above, the electrostatic capacity between the two divided electrodes 23a and 23b is detected by the liquid droplet position detection unit 26, and the position of the liquid droplet 21 (that is, the atmosphere) is detected based on the detected electrostatic capacity. The open / close state of the communication hole 19 is detected. The detection result is output to the valve control unit 31.

  Therefore, the valve control unit 31 can monitor the open / closed state of the air communication hole 19 based on the detection result by the droplet position detection unit 26. Based on the monitoring result, the valve control unit 31 can control the valve 11 not only during the recording operation described above but also during the purge operation. For example, when the ink cartridge 5 is detached from the ink jet printer 100 and reattached, an ink cartridge attachment / detachment detector (not shown) detects the length of time that the ink cartridge 5 has been detached from the ink jet printer 100. Further, when the time when the ink cartridge 5 has been removed exceeds a predetermined value, it is determined that the ink in the ink cartridge 5 has been dried, and a purge operation is performed. At this time, if the detection result that the atmospheric communication hole 19 is closed is output by the droplet position detection unit 26, it is necessary to open the atmospheric communication hole 19 in order to perform purging. Therefore, the valve control unit 31 outputs a signal for opening the atmosphere communication hole 19 to the potential applying unit 25. On the other hand, if a detection result indicating that the air communication hole 19 is open is output, the purging may be performed while the air communication hole 19 remains open. Therefore, the valve control unit 31 does not output a signal to the potential applying unit 25, and the atmosphere communication hole 19 is maintained in an open state until purge is performed. Further, when the time when the ink cartridge 5 has been removed does not exceed a predetermined value, it is not necessary to perform the purge operation. Accordingly, when the droplet position detection unit 26 outputs a detection result indicating that the atmospheric communication hole 19 is open, the valve control unit 31 outputs a signal for closing the atmospheric communication hole 19 to the potential applying unit 25. . On the other hand, when a detection result indicating that the atmospheric communication hole 19 is closed is output, the valve control unit 31 does not output a signal to the potential applying unit 25, and the atmospheric communication hole 19 is in the next recording operation or purging. Until it is closed.

  According to the first embodiment described above, the following effects can be obtained. By applying different potentials to the first electrode 22 and the second electrode 23, the liquid repellency (wetting angle) on the surface of the insulating layer 24 covering the electrodes 22 and 23 is made different, thereby disposing the first electrode 22. Between the region and the region where the second electrode 23 is disposed, the droplet 21 can be transferred from a region having high liquid repellency to a region having a low liquid repellency. That is, the air communication hole 19 can be opened and closed by the droplet transfer unit 20 having a simple configuration including the two electrodes 22 and 23 and the insulating layer 24. In addition, since the ground electrode 27 held at the ground potential is disposed in the region where the first electrode 22 and the second electrode 23 are disposed in the insulating layer 24, the potential of the droplet 21 is always the ground potential. Retained. Therefore, since the potential difference between the electrodes 22 and 23 and the droplet 21 is stabilized, the transfer operation of the droplet 21 can be performed reliably.

  Furthermore, since the second electrode 23 is divided into two divided electrodes 23a and 23b that are spaced apart from each other, the droplet position detection unit 26 causes a capacitance between the two divided electrodes 23a and 23b. Based on the above, it is possible to detect in which arrangement region of the first electrode 22 and the second electrode 23 the droplet 21 is present.

  Further, by applying the present invention to the valve 11 for opening and closing the atmosphere communication hole 19 of the ink cartridge 5, the liquid droplet 21 is transferred to the first electrode 22 when the ink is not supplied from the ink cartridge 5 to the inkjet head 1. Thus, the atmosphere communication path 19 can be closed. On the other hand, when supplying ink, the droplet 21 can be transferred to the second electrode 23 to open the atmosphere communication path 19. That is, the ink droplet drying unit (thickening) can be effectively prevented without causing ink shortage by the droplet transfer unit 20 or the valve 11 having a simple configuration.

  Next, modified embodiments in which various modifications are made to the above-described first embodiment will be described. However, components having basically the same configuration as those of the first embodiment are denoted by the same reference numerals and description thereof is omitted as appropriate.

Modified embodiment 1
In the first embodiment, the second electrode 23 is divided into two divided electrodes 23 a and 23 b and is disposed on the upper surface 10 b of the bottom wall 10 a of the cartridge body 10 together with the first electrode 22. However, as shown in FIGS. 27A and 27B, a single second electrode 123 is disposed on the upper surface 10 b of the bottom wall 10 a of the cartridge body 10 together with the first electrode 22. Different third electrodes 124 may be arranged parallel to the upper surface 10 b of the bottom wall 10 a and spaced apart from the second electrode 123. In this case, one side 23a and the other side 23b of the divided electrodes in the first embodiment correspond to the second electrode 123 and the third electrode 124 in the present modified embodiment, respectively. FIGS. 27A and 27B are diagrams for illustrating the positional relationship between the second electrode 123 and the third electrode 124. 27A is a top view of the droplet transfer device 20, and FIG. 27B is a cross-sectional view taken along the line XXVIIB-XXVIIB in FIG.

  In the droplet transfer unit 20 of this form, the air communication hole 19 is formed in the bottom wall 10a of the cartridge body 10 as in the first embodiment. A first electrode 22 is disposed on the upper surface 10b of the bottom wall 10a. In addition, a single rectangular second electrode 123 is disposed in the vicinity of the first electrode 22 on the upper surface 10b of the bottom wall 10a at a predetermined distance from the first electrode 22. An insulating layer 24 is formed so as to completely cover both the first electrode 22 and the second electrode 123. Two ground electrodes 27 are disposed on the insulating layer 24 covering the first electrode 22 and the second electrode 123, respectively. Furthermore, the third electrode 124 is disposed so as to be parallel to the upper surface 10 b of the bottom wall 10 a and to face the second electrode 123. That is, the third electrode 124 is disposed so as to cover the second electrode 123 when the droplet transfer unit 20 is viewed from above (above the paper surface of FIG. 27A). (In FIG. 27A, the second electrode 123 completely overlaps the third electrode 124.) The planar shape of the third electrode 124 is the same rectangle as the planar shape of the second electrode 123. The third electrode 124 is connected to the droplet position detector 26 shown in FIG. 4 together with the second electrode 123. The droplet position detection unit 26 detects the capacitance between the second electrode 123 and the third electrode 124.

  According to the principle described in the first embodiment, when the droplet 21 is transferred from the first electrode 22 to the second electrode 123, the droplet 21 exists between the second electrode 123 and the third electrode 124 facing the second electrode 123. Then, both electrodes 123 and 124 are in contact with each other. At this time, the second electrode 123, the third electrode 124, the conductive liquid 21, and the insulating layer 24 constitute a capacitor. Therefore, when the droplet 21 exists on the second electrode 123, a predetermined capacitance is detected between the second electrode 123 and the third electrode 124 by the droplet detection unit 26. On the other hand, when the droplet 21 is not on the second electrode 123, the electrostatic capacitance is not detected by the droplet position detection unit 26, or the detected value is a value considerably lower than a predetermined value. That is, according to the modified embodiment 1, it is possible to detect whether or not the droplet 21 exists on the second electrode 123 by measuring the capacitance. In addition, when the droplet transfer unit 20 is viewed from above, the third electrode 124 is disposed so as to cover the second electrode 123, so that as long as the droplet 21 exists on the second electrode 123, The third electrode 124 can contact the droplet 21 even if it exists at a position off the center of the two electrodes 123. Therefore, even if the droplet 21 is present at a position off the center of the second electrode, the presence of the droplet 21 can be reliably detected. Note that an insulating layer 24 is formed on the first electrode 22 and the second electrode 123 as in the first embodiment. Therefore, even if the insulating layer 24 is not formed on the surface of the third electrode 124 facing the second electrode 123, by applying different potentials to the first electrode 22 and the second electrode 123, the first electrode 22 is provided. The droplet 21 can be moved between the region where the is disposed and the region where the second electrode 123 is disposed.

  In the modified embodiment 1, the distance between the third electrode 124 and the insulating layer 24 may be an interval at which the third electrode 124 can reliably contact the droplet 21 when the droplet 21 exists on the second electrode 123. That's fine. Further, the planar shape of the third electrode 124 is rectangular in this example like the second electrode 123, but when the droplet 21 exists on the second electrode 123, the third electrode 124 becomes the droplet 21. The shape of the second electrode 123 may be different from the planar shape as long as it can be reliably contacted.

Modified embodiment 2
A modified embodiment 2 obtained by modifying the modified embodiment 1 will be described with reference to FIGS. 28 (a) and 28 (b). FIGS. 28A and 28B are diagrams for illustrating the positional relationship between the second electrode 123 and the third electrode 224 in the first modified embodiment. 28A is a top view of the droplet transfer device 20, and FIG. 28B is a cross-sectional view taken along line XXVIIIB-XXVIIIB in FIG. The modified embodiment 2 differs from the modified embodiment 1 in that the two ground electrodes 27 are not present in the droplet transfer device. Further, when the droplet transfer device 20 is viewed from above (above the paper surface in FIG. 28A), the third electrode 224 reaches the vicinity of the upper end opening 19a of the air communication hole 19, that is, a part of the first electrode 123. The point which is extended so that it may cover is different from the modified embodiment 1. Further, the third electrode 224 is always held at the ground potential. The third electrode 224 is connected to the droplet position detector 26 shown in FIG. 4 together with the second electrode 123. The droplet position detection unit 26 detects the capacitance between the second electrode 123 and the third electrode 224. Since other structures are the same as those of the modified embodiment 1, the description thereof is omitted.

  In the modified embodiment 2, the third electrode 224 extends so as to be parallel to the upper surface 10 b of the bottom wall 10 a and to face a part of the first electrode 22 and the second electrode 123. Therefore, the third electrode 224 contacts the droplet 21 regardless of whether the droplet 21 exists in the region where the first electrode 22 is disposed or in the region where the second electrode 23a is disposed. . The third electrode 224 is always held at the ground potential. Therefore, it is not necessary to separately provide the ground electrode 27 as in the above-described embodiment. According to the principle explained in the first embodiment, when the droplet 21 is transferred from the first electrode 22 to the second electrode 123, the droplet 21 exists between the second electrode 123 and the third electrode 224 opposite to the second electrode 123. Then, both electrodes 123 and 224 are in contact with each other. As a result, a capacitor including the second electrode 123, the third electrode 224, the droplet 21, and the insulating layer 24 is formed. Therefore, when the droplet 21 is present on the second electrode 123, a predetermined capacitance is detected by the droplet detection unit 26. On the other hand, when the droplet 21 is not on the second electrode 123, the droplet position detection unit 26 does not detect the capacitance or detects only a very small capacitance. Based on the principle described above, also in the modified embodiment 2, it is possible to detect whether or not the droplet 21 exists on the second electrode 23a with a simple configuration. Furthermore, since it is not necessary to separately provide a ground electrode, the number of parts can be reduced, and the valve 11 and the droplet transfer device 20 having a simpler structure can be configured. Therefore, the manufacturing cost can be reduced.

Modified embodiment 3
In the first embodiment, the second electrode 23 is divided into two divided electrodes 23a and 23b. However, the first electrode 22 may be divided. Moreover, both the 1st electrode 22 and the 2nd electrode 23 may be divided | segmented. Furthermore, the number of divisions of the first electrode 22 and the second electrode 23 is not particularly limited to two, and may be divided into a plurality of three or more divided electrodes. On the other hand, when it is not necessary to detect the position of the droplet 21, both the first electrode 22 and the second electrode 23 do not need to be divided. Further, when the fluctuation of the potential of the droplet 21 is sufficiently small with respect to the predetermined potential applied to the electrodes 22 and 23 and hardly affects the transfer of the droplet 21, the droplet 21 is held at the ground potential. For this purpose, the ground electrode 27 may be omitted.

Modified embodiment 4
The droplet transfer unit causes the droplet 21 to move to a region outside the region where the first electrode 22 and the second electrode 23 are disposed, or to a region where the opposite electrode is disposed, due to vibration of the droplet 21 or the like. It is preferable that it can prevent moving. For example, as shown in FIGS. 13 (a) and 13 (b), the liquid repellency always having higher liquid repellency than the insulating layer 24 outside the arrangement area of the first electrode 22 and the arrangement area of the second electrode 23. The film 40 (first liquid repellent film) may be formed so as to surround both of the two electrode arrangement regions. According to this configuration, the liquid repellent film 40 prevents the droplet 21 from moving outside the electrode arrangement region. As shown in FIG. 13B, the liquid repellent film 40 may be formed so as to overlap the insulating layer 24, or the arrangement area of the first electrode 22 and the arrangement area of the second electrode 23. The insulating layer 24 may not be formed on the outer side, and the liquid repellent film 40 may be directly formed on the surface of the bottom wall 10a (base material).

  Further, as shown in FIGS. 14A and 14B, the widths of the end portions of the first electrode 22 and the second electrode 23 on the adjacent sides are narrowed, and the first electrode 22 and the second electrode 23 are narrowed. In the meantime, the width of the region where the liquid repellent film 40 is not formed may be locally narrowed. In this configuration, since the width of the region in which the droplet 21 moves between the arrangement region of the first electrode 22 and the arrangement region of the second electrode 23 is narrowed, the droplet 21 is unexpectedly moved to the opposite electrode due to vibration or the like. It becomes difficult to move to.

  Alternatively, as shown in FIGS. 15A and 15B, the region between the arrangement region of the first electrode 22 and the arrangement region of the second electrode 23 always has higher liquid repellency than the insulating layer 24. A liquid repellent film 41 (second liquid repellent film) may be formed. In this configuration, the liquid repellent film 41 prevents the droplet from unexpectedly moving to the opposite electrode due to vibration or the like. Further, the liquid repellent film 41 may be formed so as to overlap the insulating layer 24 as in the case of the liquid repellent film 40 (see FIGS. 13 and 14) described above, or the surface of the bottom wall 10a. It may be formed directly on.

  Further, as shown in FIGS. 16A and 16B, a liquid repellent film 40 is formed outside the arrangement region of the first electrode 22 and the second electrode 23 on the upper surface of the insulating layer 24. The liquid repellent film 41 may be formed between these two electrode arrangement regions. In this configuration, both the movement of the droplet 21 to the outside of the electrode arrangement region and the movement of the electrode on the opposite side to the arrangement region are prevented.

  If the insulating layer 24 is made of, for example, polyimide resin or epoxy resin, and the liquid repellent films 40, 41 are made of, for example, fluorine resin, the liquid repellency of the liquid repellent films 40, 41 is used. Can be higher than that of the insulating layer 24.

  If the wetting angle of the droplet 21 on the surface of the insulating layer 24 is greater than 90 degrees, the droplet 21 is unlikely to move unexpectedly even if vibration or the like occurs. The thickness may be larger than the surface roughness of the insulating layer 24. On the other hand, when the wetting angle of the droplet 21 on the surface of the insulating layer 24 is smaller than 90 degrees, the droplet 21 is likely to move unexpectedly due to vibration or the like, so the surface roughness of the liquid repellent films 40 and 41 is insulated. The surface roughness of the layer 24 is preferably smaller.

  Further, when the liquid repellent film 41 is formed between the arrangement region of the first electrode 22 and the arrangement region of the second electrode 23, the liquid repellent film 41 is interposed between the first electrode 22 and the second electrode 23. It also becomes the resistance of the original droplet transfer. For this reason, the potential of the transfer destination electrode is set to be relatively high, and the liquid repellency in the arrangement region of the electrode is sufficiently lowered, so that the droplet 21 can reliably get over the liquid repellent film 41. It is preferable to generate a force.

  Alternatively, as shown in FIGS. 17A and 17B, a liquid repellent film 41 (second liquid repellent film) provided between the arrangement area of the first electrode 22 and the arrangement area of the second electrode 23 A part may protrude into the arrangement area of the first electrode 22 and the arrangement area of the second electrode 23, respectively. According to this configuration, the liquid repellent film 41 prevents the liquid droplet 21 from unexpectedly moving to the opposite electrode due to vibrations or the like, while liquid droplets are transferred between the two electrode arrangement regions. The droplet 21 can easily get over the liquid-repellent film 41 from the portion protruding into the electrode arrangement region, and can move smoothly between the arrangement regions of the electrodes 22 and 23.

  Note that FIGS. 13A to 17B described above show a form in which the second electrode 23 is not divided, but the above-described case is also possible when the second electrode 23 is divided. It goes without saying that the configuration is applicable.

Modified embodiment 5
The valve 11 may be configured to periodically open the atmosphere communication hole 19. When printing is not performed for a long time, the atmosphere communication hole 19 is not opened for a long time by the valve 11, so that the ink containing space 12 in the cartridge body 10 is caused by a change in atmospheric temperature or a change in atmospheric pressure. There is a risk that the pressure of the air will become excessively high or a negative pressure. Therefore, for example, when the head control unit 30 of the control device 4 determines that a predetermined time has elapsed since the time when the previous printing was completed, the valve control unit 31 controls the potential applying unit 25 with the atmosphere. When configured to output a signal for opening the communication hole 19, the air communication hole 19 is periodically opened, and the pressure difference between the inside and the outside of the cartridge main body 10 can be suppressed to be small.

Modified embodiment 6
In the first embodiment, the position of the droplet 21 is detected from the potential applying unit 25 that applies a potential to the first electrode 22 and the second electrode 23 and the capacitance between the two divided electrodes 23a and 23b. Although the droplet position detection unit 26 is provided on the printer 100 side, these may be provided on the ink cartridge 5 side and connected to the control device 4 (valve control unit 31) on the printer 100 side. Good. That is, the valve 11 of the ink cartridge 5 may include the droplet transfer unit 20 including the potential applying unit 25 and the droplet position detection unit 26.

Second Embodiment Next, a second embodiment of the present invention will be described. This 2nd Embodiment is an example which applied this invention to the nozzle cap with which the ink ejection surface of an inkjet head is mounted | worn. In addition, about the thing which has the structure similar to the said 1st Embodiment, the same code | symbol is attached | subjected and the description is abbreviate | omitted suitably.

  As in the first embodiment (see FIG. 1), the inkjet head 1 is conveyed with respect to the recording paper P (recording medium) based on a command from the control device 4 (see FIG. 20) of the inkjet printer 100. Ink is ejected while moving in a direction perpendicular to the direction. In addition, the carriage 2 is configured to be movable to a retreat position that is located on the outer side in the width direction (left-right direction in FIG. 1) than the area where the recording paper P is conveyed. A nozzle cap 60 is disposed at the retracted position, and the nozzle cap 60 is driven up and down by a cap driving unit 55 (see FIG. 20). When ink is not ejected from the nozzle 52 (see FIG. 18), the inkjet head 1 moves to the retracted position together with the carriage 2, and the nozzle cap 60 is connected to the outlets 52a of the plurality of nozzles 52 at the retracted position. The ink jet head 1 is mounted so as to cover the lower surface (ink ejecting surface 1a) of the arranged ink jet head 1 from below.

  As shown in FIG. 18, inside the inkjet head 1, a manifold 50, a plurality of individual channels 51 branched from the manifold 50, and ends of the plurality of individual channels 51 are provided. And a plurality of nozzles 52 opened on the lower surface (ink ejection surface 1a). Ink is supplied to the manifold 50 from an external ink tank (not shown) through an ink supply hole 53 provided in the upper portion of the manifold 50. Ink is supplied from the manifold 50 to the plurality of nozzles 52 via the plurality of individual flow paths 51, and the ink is ejected from the plurality of nozzles 52.

  The nozzle cap 60 includes a cap portion 61 that covers the plurality of nozzles 52 from below, an annular lip portion 62 that extends upward from the peripheral portion of the cap portion 61 and contacts the ink ejection surface 1a, and the cap portion 61 from below. A supporting base 63 is provided.

  The cap part 61 has an area larger than the area | region where the several ejection port 52a of the ink ejection surface 1a is arrange | positioned so that the ejection port 52a of the several nozzle 52 can be covered at once from the downward direction. Further, the lip portion 62 is in contact with the entire circumference of the area where the plurality of emission ports 52a of the ink ejection surface 1a are arranged, and can seal the plurality of emission ports 52a. The cap portion 61 and the lip portion 62 are formed of a material having elasticity such as a synthetic resin material.

  The bottom wall 63a (base material) of the base portion 63 is provided with a communication hole 65 (communication passage) that allows communication between the internal space 64 (space on the ink ejection surface 1a side) of the cap portion 61 and the outside (atmosphere). It has been. The communication hole 65 is used to alleviate the pressure increase in the space 64 when the nozzle cap 60 is attached and prevent the meniscus in the nozzle 52 from being destroyed. However, even when the nozzle cap 60 is attached, if the space 64 communicates with the outside, the ink in the nozzle 52 will dry over time. Therefore, the base 63 is provided with a valve 66 for opening and closing the communication hole 65.

  The valve 66 has substantially the same configuration as the valve 11 (see FIGS. 2 and 3) of the first embodiment. That is, the valve 66 includes a droplet transfer unit 20 that transfers the conductive droplet 21 on the inner surface (upper surface) of the bottom wall 63a. As shown in FIG. 19, the droplet transfer section 20 includes a first electrode 22 arranged so as to surround the upper end opening 65a of the communication hole 65 on the inner surface (upper surface) of the bottom wall 63a, and the bottom wall 63a. On the upper surface of the first electrode 22 and the second electrode 23 disposed close to the first electrode 22 at a predetermined distance, and on the upper surface of the bottom wall 63a, both the first electrode 22 and the second electrode 23 are completely covered. And an insulating layer 24. The second electrode 23 is divided into two divided electrodes 23a and 23b that are arranged apart from each other. A protective unit 67 is provided above the droplet transfer unit 20 to prevent ink mist from directly falling on the conductive droplet 21.

  When different potentials (predetermined potential or ground potential) are applied to the first electrode 22 and the second electrode 23 by the potential applying unit 25 based on a command from the control device 4 (valve control unit 69) of the printer 100. Since the liquid repellency in one electrode arrangement region is lowered, the droplet 21 is transferred between the two electrode arrangement regions. When the droplet 21 is transferred to the arrangement region of the first electrode 22, the communication hole 65 is closed by the droplet 21, and when the droplet 21 is transferred to the arrangement region of the second electrode 23, the communication hole 65 is formed. Opened.

  Further, the two divided electrodes 23 a and 23 b of the second electrode 23 are connected to the droplet position detection unit 26. Then, the droplet position detection unit 26 determines in which region of the first electrode 22 and the second electrode 23 the droplet 21 exists based on the capacitance between the two divided electrodes 23a and 23b (that is, The open / close state of the communication hole 65) can be detected.

  As shown in FIG. 20, the control device 4 of the printer 100 includes a CPU, a RAM, a ROM, and the like. Further, the control device 4 controls the inkjet head 1 based on print data input from the PC 33 and ejects ink, and a cap that controls the cap driving unit 55 to move the nozzle cap 60 up and down. A control unit 68 and a valve control unit 69 that opens and closes the valve 66 by controlling the nozzle cap 60 are provided.

  When the nozzle cap 60 is mounted on the inkjet head 1, the valve control unit 69 outputs a signal for opening the communication hole 65 to the potential applying unit 25 immediately before the nozzle cap 60 is mounted. At this time, the potential applying unit 25 applies a ground potential to the first electrode 22 and applies a predetermined potential to the second electrode 23. Then, as shown in FIG. 18, the droplet 21 is transferred from the first electrode 22 to the second electrode 23, and the communication hole 65 is opened. Therefore, the pressure increase in the space 64 in the cap portion 61 is alleviated, and the meniscus formed in the nozzle 52 is prevented from being destroyed.

  On the other hand, after the nozzle cap 60 is attached to the inkjet head 1, the valve control unit 69 outputs a signal for closing the communication hole 65 to the potential applying unit 25. At this time, the potential applying unit 25 applies a predetermined potential to the first electrode 22 and applies a ground potential to the second electrode 23. Then, as shown in FIG. 21, the droplet 21 is transferred from the second electrode 23 to the first electrode 22, and the communication hole 65 is closed by the droplet 21. Therefore, drying of the ink in the nozzle 52 is prevented.

  Further, the valve control unit 69 outputs a signal for opening the communication hole 65 to the potential applying unit 25 immediately before the nozzle cap 60 is detached from the inkjet head 1 (separated from the ink ejection surface 1a). May be. In this case, the pressure fluctuation in the space 64 in the cap portion 61 when the nozzle cap 60 is separated from the ink ejection surface 1a can be reduced, so that the meniscus is further prevented from being destroyed.

  According to the configuration of the second embodiment described above, ink drying and meniscus destruction can be prevented by the droplet transfer unit 20 having a simple configuration including the two electrodes 22 and 23 and the insulating layer 24. In addition, since the second electrode 23 is divided into two divided electrodes 23a and 23b that are spaced apart from each other, the droplet position detection unit 26 increases the capacitance between the two divided electrodes 23a and 23b. Based on this, it is possible to detect in which arrangement region of the first electrode 22 and the second electrode 23 the droplet 21 is present.

  In the second embodiment, the same change as that of the first embodiment relating to the droplet transfer unit 20 (electrode division and liquid-repellent films 40 and 41 (see FIGS. 13A to 17B). ) And the like can be added.

Third Embodiment Next, a third embodiment of the present invention will be described. The third embodiment is an example in which the present invention is applied to a storage device that is a rewritable nonvolatile memory.

  As shown in FIGS. 22A and 22B, the storage device 70 has conductivity over a substrate 71 (base material) made of a synthetic resin material and two regions on the surface of the substrate 71. The storage unit 72 includes a plurality of droplet transfer units 20 that transfer the droplets 21 and can store a plurality of bit data, and a control unit 73 (see FIG. 23) that controls each of the plurality of droplet transfer units 20. ing. In FIG. 22A, three of the plurality of droplet transfer units 20 are shown.

  Each droplet transfer unit 20 of the storage unit 72 has substantially the same configuration as that of the first embodiment. That is, as shown in FIGS. 22 (a) and 22 (b), the droplet transfer unit 20 is disposed on the surface of the substrate 71 and the first electrode 22 disposed on the surface of the substrate 71 made of a synthetic resin material. A second electrode 23 disposed close to the first electrode 22 at a predetermined distance, and an insulating layer 24 formed on the surface of the substrate 71 so as to completely cover both the first electrode 22 and the second electrode 23. Have. The second electrode 23 is divided into two divided electrodes 23a and 23b that are arranged apart from each other. Further, ground electrodes 27 are disposed on the surface of the insulating layer 24 in the region where the first electrode 22 and the second electrode 23 are disposed. The grounds 27 of the plurality of droplet transfer units 20 are electrically connected to each other via the wiring 74, and all the grounds 27 are always held at the ground potential.

  Further, as shown in FIG. 23, each droplet transfer unit 20 includes a potential applying unit 25 that applies a potential to the first electrode 22 and the second electrode 23, and a droplet position detection unit 26. The potential applying unit 25 applies different potentials (predetermined potential or ground potential) to the first electrode 22 and the second electrode 23 according to the stored data, respectively, and drops liquid droplets between the two electrode arrangement regions. 21 is transferred. Specifically, the state in which the droplet 21 is present in the arrangement region of the first electrode 22 (the state of the two lower droplet transfer units 20 in FIG. 22A) is “0” in the bit data. Correspondingly, the state in which the droplet 21 exists in the arrangement area of the second electrode 23 (the state of the uppermost droplet transfer unit 20 in FIG. 22A) corresponds to “1” of the bit data. ing. One bit data (“0” or “1”) can be stored by transferring the droplet 21 to one of the two electrode arrangement regions by one droplet transfer unit 20. Yes.

  In addition, the droplet position detection unit 26 determines in which region of the first electrode 22 and the second electrode 23 the droplet 21 exists based on the capacitance between the two divided electrodes 23a and 23b (that is, , “0” or “1” is stored), and the detection result is output to the control unit 73.

  As shown in FIG. 23, the control unit 73 is connected to an external data input / output device 75. When a plurality of bit data to be stored is input from the data input / output device 75 to the control unit 73, the control unit 73 sets the plurality of droplet transfer units 20 corresponding to the plurality of bit data, respectively. Information (“0” or “1”) on the stored bit data is output to the potential applying unit 25. When the data to be stored is “0”, the potential applying unit 25 applies a predetermined potential to the first electrode 22 and simultaneously applies a ground potential to the second electrode 23, thereby arranging the first electrode 22. The droplet 21 is transferred to the area (the lower two droplet transfer portions 20 in FIG. 22A). On the other hand, when the data to be stored is “1”, the potential applying unit 25 applies the ground potential to the first electrode 22 and simultaneously applies the predetermined potential to the second electrode 23, The droplet 21 is transferred to the arrangement region (the uppermost droplet transfer portion 20 in FIG. 22A). In this way, the input bit data is stored in the storage unit 72. After the transfer of the droplet 21 is completed, the potentials of the first electrode 22 and the second electrode 23 are both switched to the ground potential, and the state is maintained. The stored data never disappears.

  In addition, the control unit 73 detects whether the droplet 21 exists in the arrangement region of the first electrode 22 or the arrangement region of the second electrode 23 from the droplet position detection unit 26 of the plurality of droplet transfer units 20. Is entered. That is, the control unit 73 can detect which data “0” or “1” is stored by one droplet transfer unit 20 of the storage unit 72. Then, in response to a request from the data input / output device 75, the control unit 73 reads the data stored in the storage unit 72 and outputs it to the data input / output device 75.

  According to the configuration of the third embodiment described above, 1-bit data can be stored by the droplet transfer unit 20 having a simple configuration including the two electrodes 22 and 23 and the insulating layer 24. In addition, since the second electrode 23 is divided into two divided electrodes 23a and 23b that are spaced apart from each other, the droplet position detection unit 26 increases the capacitance between the two divided electrodes 23a and 23b. Based on this, it is possible to detect in which arrangement region of the first electrode 22 and the second electrode 23 the droplet 21 is present. Accordingly, the stored 1-bit data type can be determined, and the data can be read out. Further, the storage device 70 according to the third embodiment can be manufactured at a lower cost because a substrate made of a synthetic resin is used unlike a silicon substrate used in a normal semiconductor storage device.

  In addition, also in this third embodiment, the same change as the change in the first embodiment relating to the droplet transfer unit 20 (addition of the liquid repellent films 40 and 41 (see FIGS. 13A to 17B)). Etc.) can be added. However, in order to read data already stored in the storage unit 72, at least one of the first electrode 22 and the second electrode 23 is divided into a plurality of divided electrodes, and the first electrode 22 and the second electrode are divided. It is at least necessary to be configured so as to be able to detect which of the droplets 21 is present. In the third embodiment, the storage device 70 can store bit data (a binary value of “0” or “1”), but each of the first and second electrodes is arranged in a line. By arranging a plurality of divided electrodes like the second electrode, the storage device 70 can store multi-value information of three or more values.

Fourth Embodiment Next, a fourth embodiment of the present invention will be described. The fourth embodiment is an example in which the present invention is applied to a display device that displays desired characters, images, and the like.

  As shown in FIG. 24, the display device 80 includes a substrate 81 and a plurality of droplets that respectively transfer the colored droplets 21 having conductivity over two regions on the surface of the substrate 81 (base material). A display unit 82 composed of the transfer unit 20, a cover plate 83 disposed opposite to the surface of the substrate 81, and a control unit 84 (see FIG. 25) for controlling the plurality of droplet transfer units 20 of the display unit 82, respectively. It has. In FIG. 24, three of the plurality of droplet transfer units 20 are shown.

  Each droplet transfer unit 20 of the display unit 82 has substantially the same configuration as that of the first embodiment. That is, as shown in FIG. 24, the droplet transfer unit 20 is disposed close to the first electrode 22 disposed on the surface of the substrate 81 and on the surface of the substrate 81 with a predetermined distance from the first electrode 22. And the insulating layer 24 formed on the surface of the substrate 81 so as to completely cover both the first electrode 22 and the second electrode 23. The second electrode 23 is divided into two divided electrodes 23a and 23b that are arranged apart from each other. Furthermore, a ground 27 is disposed on the surface of the insulating layer 24 in the region where the first electrode 22 and the second electrode 23 are disposed. The grounds 27 of the plurality of droplet transfer units 20 are electrically connected to each other via the wiring 85, and all the grounds 27 are always held at the ground potential.

  As shown in FIG. 25, each droplet transfer unit 20 includes a potential applying unit 25 that applies a potential to the first electrode 22 and the second electrode 23, and a droplet position detection unit 26. The potential applying unit 25 applies different potentials (predetermined potentials or ground potentials) to the first electrode 22 and the second electrode 23 based on a command from the control unit 84, and between the two electrode arrangement regions. The droplet 21 is transferred. In addition, the droplet position detection unit 26 detects in which region of the first electrode 22 and the second electrode 23 the droplet 21 is present based on the capacitance between the two divided electrodes 23a and 23b. The detection result is output to the control unit 84.

  As shown in FIG. 24, the cover plate 83 faces the surface of the substrate 81 on which the first electrode 22 and the second electrode 23 are disposed. Further, a penetrating transmission hole 83 a is formed at a position of the cover plate 83 facing the first electrode 22. Therefore, when viewed from the opposite side of the substrate 81 of the cover plate 83, the arrangement region of the first electrode 22 can be seen through the transmission hole 83a, but the arrangement region of the second electrode 23 is blocked by the cover plate 83 and cannot be seen. Therefore, in the state where the colored droplet 21 exists in the arrangement region of the first electrode 22 (the state of the two lower droplet transfer units 20 in FIG. 24A), the color of the droplet 21 is displayed. However, in the state where the droplet 21 does not exist in the arrangement region of the second electrode 23 (the state of the uppermost droplet transfer unit 20 in FIG. 24A), the color of the droplet 21 is not displayed, The color (for example, white) of the insulating layer 24 that is the base is displayed.

  As shown in FIG. 25, the control unit 84 is connected to an external input device 85. Then, when data relating to displayed characters, images, and the like are input from the input device 85 to the control unit 84, the control unit 84 selects characters or characters to be displayed among the plurality of droplet transfer units 20 of the display unit 82. A signal that causes the potential applying unit 25 of the droplet transfer unit 20 corresponding to an image or the like to be displayed is output. Then, the potential applying unit 25 of the droplet transfer unit 20 to which the signal is input applies a predetermined potential to the first electrode 22 and at the same time applies a ground potential to the second electrode 23 so that the first electrode 22 is disposed in the region where the first electrode 22 is disposed. The droplet 21 is transferred. At this time, the color of the droplet 21 transferred to the arrangement area of the first electrode 22 is displayed through the transmission hole 83 a of the cover plate 83.

  Further, the position information of the droplet 21 detected by the droplet position detection unit 26 is input to the control unit 84. Therefore, the control unit 84 can recognize characters and images that are actually displayed from the position information of the droplet 21.

  According to the configuration of the fourth embodiment described above, desired characters, images, and the like can be displayed by the droplet transfer unit 20 having a simple configuration including the two electrodes 22 and 23 and the insulating layer 24. In addition, since the second electrode 23 is divided into two divided electrodes 23 a and 23 b that are arranged apart from each other, the droplet 21 exists in any arrangement region of the first electrode 22 and the second electrode 23. Can be detected, and characters and images that are actually displayed can be recognized. Furthermore, the droplet 21 does not move from the arrangement region of the first electrode 22 or the arrangement region of the second electrode 23 unless different potentials are applied to the first electrode 22 and the second electrode 23. That is, in the state where the droplet 21 exists in the arrangement region of the first electrode 22 and the color of the droplet is displayed, unless the potential applied to the first electrode 22 and the potential applied to the second electrode 23 are different, Since the liquid droplet does not move to the arrangement area of the second electrode 23, the display state is maintained. Further, when the droplet 21 is present in the arrangement region of the second electrode 23 and the color of the droplet is not displayed, unless the potential applied to the first electrode 22 and the potential applied to the second electrode 23 are different from each other, The droplet does not move to the arrangement area of the first electrode 22, and the state where the color of the droplet is not displayed is maintained. That is, it is not necessary to always supply power in order to maintain the same display state. Therefore, the same display state can be maintained without consuming power.

  In addition, also in the fourth embodiment, changes similar to those in the first embodiment relating to the droplet transfer unit (electrode division and liquid repellent films 40 and 41 (see FIGS. 13A to 17B)). Etc.) can be added.

  In addition to these, the following modifications can be further added to the above-described fourth embodiment. For example, when the cover plate is disposed so as to face only the placement region of the second electrode 23 and does not face the placement region of the first electrode 22, a transmission hole 83 a is formed in the cover plate 83. You don't have to.

  Further, the first electrode 22 and the second electrode 23 are formed of a transparent ITO (Indium-Tin Oxide) thin film and the like, and the insulating layer 24 is formed of a substantially transparent fluorine-based resin or the like. If the substrate 81 is formed of a transparent material such as glass, the color of the droplet 21 is displayed even from the surface of the substrate 81 opposite to the electrodes 22 and 23. Therefore, in such a case, the cover plate 83 may be disposed so as to face the surface of the substrate 81 opposite to the electrodes 22 and 23 (below the substrate 81 in FIG. 24B). .

  Further, the first electrode 22, the portion of the substrate 81 in the arrangement region of the first electrode 22, and the insulating layer 24 in the arrangement region of the first electrode 22 are all transparent, while the second electrode 23, At least one of the portion of the substrate 81 in the arrangement region of the second electrode 23 and the portion of the insulating layer 24 in the arrangement region of the second electrode 23 has non-transmissibility (a property that does not transmit light). May be. In this configuration, since the arrangement area of the second electrode 23 is non-permeable, when viewed from the side opposite to the electrodes 22 and 23 of the substrate 81 (below the substrate 81 in FIG. 24B), Since the droplet 21 existing in the arrangement area of the two electrodes 23 is not visible, the cover plate 83 is not necessary.

  In the above-described embodiments and modifications, the shape, structure, and material of the electrode and base material have been described by taking specific examples as examples. However, the present invention is not limited to these, and any shape may be used as long as it produces the action of the present invention. Things can be used. The above-described embodiments and modifications thereof are examples in which the present invention is applied to valves and the like used in ink cartridges, but the forms to which the present invention can be applied are not limited to these. For example, the droplet transfer device or valve of the present invention can be applied to a fluid supply device such as a gas or a liquid used for a micro robot or a medical device.

1 is a schematic configuration diagram of an inkjet printer according to a first embodiment of the present invention. It is a longitudinal cross-sectional view of an ink cartridge. (A) is a top view of the droplet transfer part of 1st Embodiment, (b) is the IIIB-IIIB sectional view taken on the line of (a). 1 is a block diagram illustrating an electrical configuration of an inkjet printer according to a first embodiment. It is a figure which shows schematically the circuit comprised with a 2nd electrode, an insulating layer, and a droplet in the state in which the droplet exists in the arrangement | positioning area | region of a 2nd electrode. (A) is a top view which shows the droplet transfer part in the state in which the droplet exists in the arrangement | positioning area | region of a 1st electrode, (b) is the VIB-VIB sectional view taken on the line of (a). (A) is a top view which shows the droplet transfer part just before performing the droplet transfer to a 2nd electrode, (b) is the VIIB-VIIB sectional view taken on the line of (a). (A) is a top view which shows the droplet transfer part during the droplet transfer to a 2nd electrode, (b) is the VIIIB-VIIIB sectional view taken on the line of (a). (A) is a top view which shows the droplet transfer part immediately after the droplet transfer to a 2nd electrode, (b) is the IXB-IXB sectional view taken on the line of (a). (A) is a top view which shows the droplet transfer part in the state in which the droplet exists in the arrangement | positioning area | region of a 2nd electrode, (b) is the XB-XB sectional view taken on the line of (a). It is a longitudinal cross-sectional view of the ink cartridge in a state where the air communication hole is closed. FIG. 3 is a longitudinal sectional view of the ink cartridge in a state where an air communication hole is opened. (A) is a top view which shows the droplet transfer part by which the liquid repellent film was formed in the outer side of two electrodes in the modification 4 of 1st Embodiment, (b) is the XIIIB-XIIIB line | wire of (a). It is sectional drawing. (A) is a top view which shows the droplet transfer part which deform | transformed the planar shape of two electrodes in the change Embodiment 4 of 1st Embodiment, (b) is the XIVB-XIVB sectional view taken on the line of (a). . (A) is a top view which shows the droplet transfer part by which the liquid repellent film was formed between two electrodes in the modification 4 of 1st Embodiment, (b) is the XVB-XVB line | wire of (a). It is sectional drawing. (A) is a top view which shows the droplet transfer part in which the liquid repellent film was formed in the outer side of two electrodes and between them in the modification 4 of 1st Embodiment, (b) is XVI- of (a). It is a XVIB line sectional view. (A) is a top view which shows the droplet transfer part which a part of liquid-repellent film formed between two electrodes protrudes in each electrode in the modification 4 of 1st Embodiment, (b) ) Is a sectional view taken along line XVIIB-XVIIB in (a). It is sectional drawing of the inkjet head which concerns on 2nd Embodiment, and a nozzle cap (state immediately before nozzle cap mounting | wearing). (A) is a top view which shows the droplet transfer part of 2nd Embodiment, (b) is the XIXB-XIXB sectional view taken on the line of (a). It is a block diagram which shows the electric constitution of the inkjet printer of 2nd Embodiment. It is sectional drawing of an inkjet head and a nozzle cap (nozzle cap mounting state). (A) is a top view which shows a part of memory | storage device concerning 3rd Embodiment, (b) is the XXIB-XXIIB sectional view taken on the line of (a). It is a block diagram which shows the electric constitution of the memory | storage device of 3rd Embodiment. (A) is a top view which shows a part of display apparatus concerning 4th Embodiment, (b) is the XXIVB-XXIVB sectional view taken on the line of (a). It is a block diagram which shows the electric constitution of the display apparatus of 4th Embodiment. (A) is a top view which shows the modification of the arrangement | positioning direction of the division | segmentation electrode in Fig.3 (a), FIG.5 (b) is the XXVIB-XXVIB sectional view taken on the line of (a). (A) is a top view equivalent to Drawing 3 (a) of a droplet transfer part concerning change Embodiment 1 of a 1st embodiment, and (b) is a XXVIIB-XXVIIB line sectional view of (a). (A) is a top view equivalent to Drawing 3 (a) of a droplet transfer part concerning change Embodiment 2 of a 1st embodiment, (b) is a XXVIIIB-XXVIIIB line sectional view of (a).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Inkjet head 5 Flow path unit 6 Piezoelectric actuator 10 Cavity plate (first plate)
11 Base plate (third plate)
12 Aperture plate (second plate)
16 Pressure chamber (first flow path)
16a Connection part 18 Communication hole (communication flow path)
20 Restriction channel (second channel)
20a Connection part 23 Manifold (Common liquid chamber)
25 Nozzle 26 Ink channel 40, 41, 42 Base plate (communication channel plate)
50, 51, 52 Communication holes 50a, 51a, 52a Center hole (mainstream region)
50b, 51b, 52b Notch (branch area)

Claims (20)

A droplet transfer device,
A first electrode disposed on the surface of the substrate;
A second electrode disposed on the surface of the substrate at a predetermined distance from the first electrode in the vicinity of the first electrode;
An insulating layer disposed so as to cover each of the first electrode and the second electrode, wherein the liquid repellency on the surface changes according to the potential difference between the conductive droplet present on the surface and the electrode; ,
A droplet transfer device comprising a third electrode that cooperates with the second electrode to detect the presence of a droplet on the second electrode.   2. The droplet transfer device according to claim 1, wherein at least one of the first electrode and the second electrode is divided as at least two divided electrodes that are spaced apart from each other on the surface of the base material.   The droplet transfer device according to claim 2, wherein one of the divided electrodes is a third electrode.   A portion that further includes a potential applying mechanism that applies a potential to each of the first electrode and the second electrode, and that applies different potentials to the first electrode and the second electrode by the potential applying mechanism, and covers one of the electrodes. The liquid droplets are transferred between the insulating layers covering the first electrode and the second electrode, respectively, by lowering the liquid repellency on the surface of the insulating layer than the portion covering the other electrode. Droplet transfer device. The divided electrodes are arranged such that when the droplets are transferred to a region where the divided electrodes are arranged, the droplets are in contact with both of the divided electrodes and positioned between them. ,
A droplet position detector that detects whether the droplet is present in a region where the first electrode is disposed or a region where the second electrode is disposed based on the capacitance between the divided electrodes The droplet transfer device according to claim 2, further comprising:   The droplet transfer device according to claim 1, wherein a ground electrode is disposed on a surface of the insulating layer covering the first electrode and the second electrode.   The droplet transfer device according to claim 1, wherein the third electrode extends away from the surface of the base material and faces the second electrode.   The droplet transfer device according to claim 7, wherein the third electrode extends as opposed to a part of the first electrode and the second electrode and is installed as a ground electrode.   The first liquid repellent film having a liquid repellency higher than the liquid repellency of the insulating layer is always formed in a region outside the first electrode and the second electrode on the surface of the base material. The droplet transfer device as described.   The droplet transfer device according to claim 9, wherein a width of a region where the first liquid repellent film is not formed is locally narrowed between the first electrode and the second electrode.   2. The second liquid repellent film having a liquid repellency higher than the liquid repellency of the insulating layer is always formed in a region between the first electrode and the second electrode on the surface of the base material. The droplet transfer device as described.   The droplet transfer device according to claim 11, wherein a part of the second liquid repellent film protrudes into a region where the first electrode and the second electrode are respectively disposed.   2. A valve including the droplet transfer device according to claim 1, wherein a fluid passage opening in a region where the first electrode is disposed is formed in the base material, and the region where the first electrode is disposed A valve in which the opening of the fluid passage is closed by the droplet when the droplet is present, and the opening of the fluid passage is opened when the droplet is present in a region where the second electrode is disposed. Provided in an ink cartridge having an ink containing space for containing ink, and an air communication path for communicating the ink containing space with the atmosphere;
The valve according to claim 13, wherein the atmospheric communication path is opened and closed by transferring the droplet between the first electrode and the second electrode.   A cap that covers an ink ejection surface of an ink jet head that ejects ink onto a recording medium, the cap having a communication path that communicates the space formed by the ink ejection surface and the cap with the outside of the cap. The valve according to claim 13, which is provided and opens and closes the communication path by transferring the droplet between the first electrode and the second electrode.   A storage device comprising the droplet transfer device according to claim 1, wherein the droplet transfer device transfers the droplet between the first electrode and the second electrode according to data stored in the storage device. Storage device to be transferred.   A display device comprising: the droplet transfer device according to claim 1; and a cover plate that is disposed to face the surface of the substrate and has a transmission hole formed at a position corresponding to the first electrode. The liquid droplets are colored, and the liquid droplet transfer device transfers the liquid droplets between the first electrode and the second electrode in accordance with data to be displayed on the display device.   2. A display device comprising the droplet transfer device according to claim 1, wherein the first electrode, the portion of the base material corresponding to the first electrode, and the portion of the insulating layer corresponding to the first electrode are all present. A display device that is transparent, and at least one of the second electrode, the portion of the base material corresponding to the second electrode, and the portion of the insulating layer corresponding to the second electrode is non-transmissive. A valve,
A substrate having a fluid passage opening at its surface;
A first electrode disposed on a surface of the base material in a region including an opening of the fluid passage;
A second electrode disposed on the surface of the substrate at a predetermined distance from the first electrode in the vicinity of the first electrode;
An insulating layer that is disposed so as to cover the first electrode and the second electrode, respectively, and whose liquid repellency changes on the surface according to a potential difference between the conductive droplet present on the surface and the electrode. Prepared,
The opening of the fluid passage is closed by transferring the droplet to the region where the first electrode is arranged, and the opening of the fluid passage is made by transferring the droplet to the region where the second electrode is arranged. Valve to open.   An ink cartridge comprising the valve according to claim 17.

Images