JP2007290251A - Humidifying mechanism of liquid tank and liquid droplet ejector - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To obtain a humidifying mechanism of a liquid tank in which a permanent moisturizing effect is obtained and a viscosity increase of liquid is prevented, and to obtain a liquid droplet ejector. <P>SOLUTION: A housing 32 having a pressure releasing opening 42 which communicates with the outside air is attached to an atmosphere communication opening 48 which releases the pressure inside of a sub ink tank 28. When a voltage is applied to a humidifying unit 36 by a control circuit 44 and a power source 58, the interior of the housing 32 is humidified because hydrogen ions taken in from the outside of the housing 32 are turned into water molecules at the inside of the housing 32. The water vapor inside of the housing 32 reaches the interior of the sub ink tank 28 through the atmosphere communication opening 48 and humidifies the interior of the sub ink tank 28. A moisturized state of ink inside the sub ink tank 28 is maintained in this way. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a humidification mechanism for a liquid tank that stores liquid and a droplet discharge device.

  In an apparatus using a liquid such as an ink jet printer, an ink tank for storing the liquid is used. The liquid in the ink tank is discharged onto the recording medium by the droplet discharge means. There are ink tanks that are supplied with liquid from the outside, and ink tanks that are detachably replaced according to the decrease in the liquid in the ink tank, and in devices that use liquids of multiple colors Depending on the number of colors to be used, a plurality of ink tanks are provided.

  An air communication port is provided on the side wall of the liquid tank in order to release the pressure inside the liquid tank that has changed due to a temperature change or the like. Since the pressure in the liquid tank is appropriately released by the atmosphere communication port and stabilized within a predetermined range, abnormal discharge or scattering of the liquid in the droplet discharge portion can be prevented, and a high-quality image can be obtained.

  Here, one of the problems that the liquid tank has is that water in the liquid tank evaporates from the air communication port and causes the liquid to thicken. When the liquid inside the liquid tank thickens, the liquid stays in the flow path and eventually closes the flow path, which causes problems such as abnormal discharge or non-discharge of the liquid. Therefore, various proposals have been made for the purpose of reducing the evaporation amount of water from the atmosphere communication port.

  For example, Patent Document 1 discloses an ink jet recording apparatus provided with a vent hole sealing means for sealing a vent hole in a case. According to the ink jet recording apparatus of Patent Document 1, since the air hole of the ink cartridge is sealed by the air hole sealing means, it is difficult for the ink to thicken even when left for a long time.

  However, if the vent hole is completely sealed, it is not possible to cope with a change in the internal pressure inside the ink cartridge due to a temperature change or the like, and a problem such as ink overflowing from the nozzle occurs.

  Patent Document 2 discloses an ink tank in which a communication portion that communicates the upper space of the ink chamber and the upper space of the waste ink chamber is provided, and a ventilation portion that communicates with the atmosphere is provided on the waste ink chamber side. According to the ink tank of Patent Document 2, since saturated air enters from the waste ink chamber into the ink chamber, it is difficult for water to evaporate from the ink in the ink chamber, and the ink viscosity change is reduced.

  However, when the usage frequency is low, the amount of waste ink in the waste ink chamber is small, so that the ink cannot be sufficiently humidified, and the humidification effect cannot be exhibited over a long period of time. In addition, since the ink in the ink chamber comes into contact with the atmosphere, the moisture in the ink eventually evaporates.

  Patent Document 3 discloses an ink jet cartridge provided with a shutter for capping a discharge nozzle and a communication hole of the ink jet cartridge. According to the ink jet cartridge of Patent Document 3, since the discharge nozzle and the communication hole are capped by the shutter, ink evaporation and drying are reduced.

  However, since the discharge nozzle and the communication hole are only capped by the shutter, similarly to the ink cartridge of Patent Document 1, it cannot cope with the change in the internal pressure of the ink cartridge due to a temperature change or the like, and the ink overflows from the nozzle. Will occur.

  Patent Document 4 discloses an ink cartridge in which a partition is provided in a communication portion that opens an ink containing portion to the atmosphere, and an air flow restriction member is provided in one air flow restriction chamber defined by the partition. According to the ink cartridge of Patent Document 4, since the air flow restriction member is separated from the ink storage portion and the air flow is restricted without causing the air flow restriction member to absorb ink, the air flow rate is reduced, and the ink flow is reduced. Evaporation is reduced.

  However, if the air flow rate is reduced, it becomes impossible to cope with a change in the internal pressure of the ink cartridge due to a temperature change or the like, and problems such as ink overflowing from the nozzles occur. Further, when the air flow rate is increased, the ink is evaporated.

  In Patent Document 5, there is provided an ink tank in which an air hole and an air passage communicating with the air hole are provided in an ink tank main body or a lid, and the air passage is formed in a labyrinth structure having a portion substantially perpendicular to the tank bottom. It is disclosed. According to the ink tank of Patent Document 5, since the air passage is narrow with a labyrinth structure and becomes a long passage, ink evaporation is reduced.

However, since the air passage is only lengthened, if air enters and exits due to a temperature change or the like, evaporation is promoted as a result, and ink thickening occurs.
JP 2000-108380 A JP 2003-305866 A JP-A-6-064181 JP-A-9-099564 JP-A-11-105305

  The present invention has been made in view of the above-described facts, and an object of the present invention is to obtain a humidification mechanism and a droplet discharge device for a liquid tank that can provide a permanent moisturizing effect and hardly increase the viscosity of the liquid.

A humidification mechanism for a liquid tank according to claim 1 of the present invention includes a housing having a vent hole communicating with the inside of the liquid tank, a pressure release port for releasing the pressure inside the liquid tank, and a wall surface of the housing. In the above-described configuration, comprising a solid electrolyte membrane that forms part of the hydrogen ions taken from the outside as water molecules in the housing, and power supply means for applying a voltage to the solid electrolyte membrane Accordingly, when the power supply means applies a voltage to the solid electrolyte membrane, hydrogen ions taken from the outside by the solid electrolyte membrane are converted into water molecules in the housing, so that the inside of the housing is humidified. Further, since the inside of the liquid tank is also humidified through the air communication port and the vent hole, a permanent moisturizing effect can be obtained with a simple configuration, and it is difficult for the liquid to thicken. Furthermore, since the pressure inside the liquid tank can be released from the pressure release port,
Problems such as abnormal liquid discharge are eliminated.

  According to a second aspect of the present invention, there is provided a humidifying mechanism for a liquid tank comprising: a housing; a connecting portion formed in the housing and connected to an air communication port that opens the liquid tank to the atmosphere; and the connecting portion and the air communication port. A moving means for attaching and detaching; a solid electrolyte membrane that constitutes a part of the wall surface of the housing; hydrogen ions taken from the outside are used as water molecules in the housing; and a power supply means for applying a voltage to the solid electrolyte membrane; It is provided with.

  According to the above configuration, since the connecting portion is attached to and detached from the atmosphere communication port by the moving means, when the liquid tank is excessively humidified, the connection port is detached from the atmosphere communication port and the liquid tank is humidified. Can be stopped. Also, when releasing the pressure inside the liquid tank, remove the connecting part from the atmosphere communication port and directly release the internal pressure from the atmosphere communication port. Can be released.

  A liquid tank humidification mechanism according to a third aspect of the present invention is the liquid tank humidification mechanism according to the second aspect, wherein the power supply means is configured such that when the connection portion is connected to the atmosphere communication port, A voltage is applied to the solid electrolyte membrane.

  According to the above configuration, since the voltage is applied to the solid electrolyte membrane when the housing is connected to the atmosphere communication port, energy saving can be achieved.

  A humidifying mechanism for a liquid tank according to a fourth aspect of the present invention includes a housing, a pressure release port provided in the housing, an air communication port for opening the inside of the liquid tank to the atmosphere, and a relay member for connecting the inside of the housing; A solid electrolyte membrane that constitutes a part of the wall surface of the housing and uses hydrogen ions taken from outside as water molecules in the housing, and a power supply means for applying a voltage to the solid electrolyte membrane are provided. And

  According to the above configuration, by changing the length and shape of the relay member, the installation position of the housing with respect to the liquid tank can be changed, so that various layouts of components are possible.

  A humidifying mechanism for a liquid tank according to a fifth aspect of the present invention is the humidifying mechanism for a liquid tank according to the fourth aspect, wherein the relay member is a flexible bendable tube.

  According to the above configuration, the relay member is a flexible bendable tube, and even if the housing is fixed at a specific location, the relay member can be bent appropriately to supply humidity to the liquid tank. The position can be freely moved, and various parts can be laid out.

  A humidifying mechanism for a liquid tank according to a sixth aspect of the present invention is the humidifying mechanism for a liquid tank according to the fourth or fifth aspect, comprising a waste liquid tank for storing the liquid waste liquid and covering the solid electrolyte membrane. It is characterized by that.

  According to the above configuration, since the inside of the liquid tank is humidified by the solid electrolyte membrane using the liquid water vapor stored in the waste liquid tank, the water in the waste liquid can be effectively used.

  A humidification mechanism for a liquid tank according to a seventh aspect of the present invention is the humidification mechanism for a liquid tank according to any one of the first to sixth aspects, wherein the inside of the frame portion protruding from the side wall of the housing. The solid electrolyte membrane is attached to the substrate.

  According to the said structure, since a frame part protects a solid electrolyte membrane, it becomes difficult to damage a solid electrolyte membrane.

  The liquid tank humidification mechanism according to claim 8 of the present invention is the liquid tank humidification mechanism according to any one of claims 1 to 7, wherein the solid electrolyte membrane includes a polymer electrolyte membrane, A porous negative electrode provided on one side of the polymer electrolyte membrane facing the inside of the housing, and a porous positive electrode provided on the other side of the polymer electrolyte membrane facing the outside of the housing. And an electrode.

  According to the above configuration, when a voltage is applied to the porous positive electrode and the porous negative electrode by the power supply means, a water decomposition reaction occurs at the porous positive electrode to generate hydrogen ions. Hydrogen ions permeate the polymer electrolyte membrane and reach the porous negative electrode. In the porous negative electrode, water molecules are generated by hydrogen ions and surrounding oxygen. Thereby, since the inside of a liquid tank can be humidified, it becomes difficult to generate | occur | produce the viscosity of a liquid.

  A humidifying mechanism for a liquid tank according to a ninth aspect of the present invention is the humidifying mechanism for a liquid tank according to the eighth aspect, wherein the polarity of the voltage applied by the power supply means is changed and the porous negative electrode is made porous positive. The electrode is characterized in that the porous positive electrode is changed to a porous negative electrode.

  According to the above configuration, when the interior of the liquid tank is humidified and saturated, the polarity of the voltage applied by the power supply means is reversed, and the decomposition reaction of water molecules proceeds in the porous negative electrode, so that the porous positive electrode Since the formation reaction of water molecules proceeds at the electrode, condensation inside the cap can be prevented.

  A droplet discharge device according to a tenth aspect of the present invention includes the humidifying mechanism for a liquid tank according to any one of the first to ninth aspects.

  According to the above configuration, when the power supply means applies a voltage to the solid electrolyte membrane, hydrogen ions taken from the outside by the solid electrolyte membrane are converted into water molecules in the housing, and the liquid tank is humidified through the atmosphere communication port. The internal moisturizing state is maintained. Accordingly, a permanent moisturizing effect can be obtained with a simple configuration, and it is difficult for the liquid to thicken. Further, nozzle clogging due to the thickening of the liquid can be prevented, and the image quality does not deteriorate.

  In a droplet discharge device according to an eleventh aspect of the present invention, the power supply unit includes a first power supply unit that supplies power from a commercial AC power supply, and a first power supply unit that supplies power from a power supply provided inside the droplet discharge device. 2 power supply means, and a power supply selection means for switching between the first power supply means and the second power supply means according to the connection state to the commercial AC power supply.

  According to the above configuration, even if the droplet discharge device is disconnected from the commercial AC power source and may not be used for a long time, the inside of the cap can be humidified for a long time by supplying power from the internal power source, It is possible to prevent nozzle clogging due to liquid thickening.

  In a droplet discharge device according to a twelfth aspect of the present invention, the second power supply means is a fuel cell, and includes a storage tank that covers the solid electrolyte membrane and stores water generated by the fuel cell. Features.

  According to the above configuration, the water inside the cap is humidified by the solid electrolyte membrane using the water vapor stored in the storage tank, so that the water generated by the fuel cell can be used effectively.

  In the humidifying mechanism and the droplet discharge device of the liquid tank of the present invention, a permanent moisturizing effect can be obtained with a simple configuration, and it is difficult for the liquid to thicken, and there are problems such as abnormal discharge and non-discharge of droplets. Disappear.

  A liquid tank humidification mechanism and a droplet discharge device according to a first embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 shows a mechanism unit and a control circuit of an ink jet printer 10 as a droplet discharge device of the present invention.

  The mechanism unit 12 of the ink jet printer 10 includes a recording medium conveying member 16 that conveys the recording medium P (for example, paper) in a certain direction, a conveying path of the recording medium P, and a conveying path of the recording medium P. And a set of guide members 18 provided along a direction perpendicular to the direction. The carriage 14 is slidably supported by a set of guide members 18. A maintenance station 20 is disposed below the guide member 18 and adjacent to the conveyance path of the recording medium P.

  A home position of the carriage 14 is set at a position facing the maintenance station 20, and this position is detected by the position sensor 22. The carriage 14, the recording medium conveying member 16, the guide member 18, the maintenance station 20, and the position sensor 22 are held by the main body housing 24.

  Image information is sent to the carriage 14 through a signal line formed on a flexible substrate (not shown). The carriage 14 includes a carriage frame 26 and a sub ink tank 28. In FIG. 1, the movement direction (main scanning direction) of the carriage 14 is indicated by an arrow M, and the movement direction (sub-scanning direction) of the recording medium P is indicated by an arrow S.

  The carriage frame 26 is movably provided along the guide member 18, and the sub ink tank 28 is detachably provided on the carriage frame 26.

  As shown in FIG. 5, the droplet discharge head 30 is provided so as to protrude below the lower surface of the carriage frame 26 (the surface facing the conveyance path of the recording medium P). The droplet discharge head 30 includes a nozzle (not shown) that discharges droplets on the lower surface.

The sub ink tank 28 can supply ink to the droplet discharge head 30.
Since the ink jet printer of this embodiment uses four colors of ink, four sub ink tanks 28 are provided corresponding to the number of each color. The four ink colors are black (Bk), yellow (Y), magenta (M), and cyan (C).

  Four droplet discharge heads 30 and nozzles (not shown) are also provided corresponding to each color ink. Here, by ejecting droplets of each color such as black, yellow, magenta, and cyan from the four nozzles (not shown) onto the recording medium P, a full-color image can be recorded.

  As shown in FIG. 1, the ink jet printer 10 transports the recording medium P by the recording medium transporting member 16 and ejects droplets according to the image information while reciprocating the carriage 14 to perform recording. An image is recorded on the medium P.

  As shown in FIG. 2, a housing 32 and an atmosphere communication head 34 are provided on the upper portion of the sub ink tank 28, and the housing 32 and the atmosphere communication head 34 are in close contact with each other.

  A humidifying unit 36 for humidifying the inside of the housing 32 is placed on a part of the surface of the housing 32. The humidifying unit 36 is attached and fixed to the inside of a fixing member 38 protruding from the side wall of the housing 32 by adhesion.

  The humidification unit 36 is connected to power lines 40 (40A, 40B). The power line 40 is a covered lead wire, and is fixed along the outer wall of the sub ink tank 28, and the terminal end is connected to a terminal (not shown). Further, the housing 32 is provided with a pressure release port 42 on the side wall opposite to the side wall facing the atmospheric communication head 34.

  A control circuit 44 is provided behind the mechanical unit 12. The control circuit 44 controls the humidity inside the housing 32 by the humidifying unit 36, the movement control of the carriage 14, the transport control of the recording medium P, the droplet discharge from the droplet discharge head 30, and the ink to the sub ink tank 28. An electronic circuit having an electronic element in which firmware prepared in advance is stored is provided. The control circuit 44 is connected to an operation panel (not shown) or a personal computer, and is provided to control the inkjet printer 10 based on an operation signal from the operation panel or an operation signal from the personal computer.

  As shown in FIG. 3, the sub ink tank 28 is provided with an atmosphere communication path 46 and an atmosphere communication port 48. The atmosphere communication path 46 is provided to release the pressure inside the sub ink tank 28 to the outside, and allows air (air) to flow into and out of the sub ink tank 28. At the end of the atmosphere communication passage 46, an atmosphere communication port 48 facing the housing 32 is provided. A ventilation hole 50 is provided at a position on the side wall of the housing 32 that faces the air communication port 48.

  In the sub ink tank 28, the pressure generated by the temperature change or the like passes through the atmosphere communication path 46, and is released from the atmosphere communication port 48 to the inside of the housing 32 through the vent hole 50. Further, the pressure released into the housing 32 is released into the atmosphere through the pressure release port 42. Thereby, the pressure inside the sub ink tank 28 is relieved.

  As shown in FIG. 3, the humidification unit 36 includes a polymer electrolyte membrane 52, a porous positive electrode 54, and a porous negative electrode 56. The polymer electrolyte membrane 52, the porous positive electrode 54, and the porous negative electrode 56 are fixed to the housing 32 by a fixing member 38 by bonding or screwing.

  The polymer electrolyte membrane 52 is a solid polymer electrolyte membrane having hydrogen ion permeability (for example, product name Nafion, manufactured by DuPont).

  The porous positive electrode 54 and the porous negative electrode 56 are porous electrodes containing platinum, a platinum group metal or the like having catalytic action, and sandwich the polymer electrolyte membrane 52 therebetween. The porous positive electrode 54 faces the outside of the housing 32, and the porous negative electrode 56 faces the inside of the housing 32. Further, the power supply line 40A is connected to the anode 54, and the power supply line 40B is connected to the cathode 56, respectively.

  Here, the principle of moisture retention will be described with reference to FIG.

  As shown in FIG. 4, a power source 58 is provided. The power source 58 includes a first electrode 59A and a second electrode 59B, and is provided so that the polarity of the voltage applied to the first electrode 59A and the second electrode 59B can be changed. FIG. 4 shows a state where the first electrode 59A side is set to a high potential (+) and the second electrode 59B side is set to a low potential (−) as an example.

  The power supply 58 and the control circuit 44 are connected by a transmission line 60 capable of transmitting an electrical signal, and a voltage is applied to the first electrode 59A and the second electrode 59B based on the signal from the control circuit 44. It has become so.

  One of the power lines 40A is connected to the porous positive electrode 54, and the other is connected to the first electrode 59A of the power source 58. One of the power lines 40B is connected to the porous negative electrode 56, and the other is connected to the second electrode 59B of the power source 58.

  Here, when a voltage is applied with the first electrode 59A of the power supply 58 set to a high potential (+) and the second electrode 59B of the power supply 58 set to a low potential (−), the porous positive electrode 54 side becomes a positive electrode, The negative electrode 56 side is the negative electrode. Conversely, when a voltage is applied with the first electrode 59A of the power source 58 set at a low potential (−) and the second electrode 59B of the power source 58 set at a high potential (+), the porous positive electrode 54 side becomes a negative electrode, The negative electrode 56 side becomes the positive electrode.

Now, based on the signal from the control circuit 44, when a voltage is applied such that the first electrode 59A of the power source 58 is at a high potential (+) and the second electrode 59B is at a low potential (−), the porous positive electrode In the electrode 54, decomposition reaction of water (H ₂ O) in the atmosphere proceeds.

H ₂ O → 2H ⁺ + 1 / 2O ₂ + 2e ⁻ (A)
Hydrogen ions (H ⁺ ) generated by the reaction A are porous from the porous positive electrode 54 through the polymer electrolyte membrane 52 having hydrogen ion permeability due to a potential difference between the porous positive electrode 54 and the porous negative electrode 56. It moves to the negative electrode 56 and reaches the porous negative electrode 56. The electrons (e ⁻ ) generated by the reaction A move to the porous negative electrode 56 via the lead wire 40A, the power source 58, and the lead wire 40B.

In the porous negative electrode 56, hydrogen ions (H +) that have reached the porous negative electrode 56, electrons (e ⁻ ) that have moved to the porous negative electrode 56, and air in the vicinity of the porous negative electrode 56. The generation reaction of water (H ₂ O) proceeds with oxygen (O ₂ ).

2H ⁺ + 1 / 2O ₂ + 2e ⁻ → H ₂ O (B)
By the reaction A and the reaction B, water is generated on the porous negative electrode 56 side.

  Therefore, the water generated on the porous negative electrode 56 side increases the humidity in the atmosphere on the porous negative electrode 56 side.

The amount of water produced by reaction A and reaction B varies depending on the hydrogen ion partial pressure [H ⁺ ], applied voltage, etc., but as reaction A and reaction B progress, water decreases near the porous positive electrode 54. However, since oxygen decreases in the vicinity of the porous negative electrode 56, the supply of water and oxygen eventually cannot catch up.

  Therefore, as long as an appropriate voltage is applied, the porous negative electrode 56 side is not excessively humidified. In the present embodiment, the applied voltage and power necessary for humidification inside the housing 32 are about 3V and 2W.

  When the polarity of the voltage applied to the porous positive electrode 54 and the porous negative electrode 56 is reversed by the control circuit 44 and the power source 58, the porous negative electrode 56 side becomes a porous positive electrode, and the reaction A proceeds. Further, the porous positive electrode 54 side becomes a porous negative electrode, and the reaction B proceeds, so that dehumidification is performed.

  Thus, moisture retention is performed according to the value of the applied voltage or the polarity of the applied voltage.

  The voltage application is performed while the inkjet printer 10 is connected to a power supply source (not shown). That is, voltage application is performed as long as power is supplied to the inkjet printer 10 by the power supply source regardless of ON / OFF of the main power switch (not shown) of the inkjet printer 10.

  A humidity sensor (not shown) is provided inside the housing 32, and the humidity sensor is connected to the control circuit 44. When a predetermined humidity value is exceeded due to an excessive applied voltage, a signal is transmitted from the humidity sensor to the control circuit 44, and the control circuit 44 applies a voltage applied from the power source 58 to the porous positive electrode 54 and the porous negative electrode 56. The inside of the housing 32 is dehumidified by changing the polarity of.

  As shown in FIG. 2, an ink supply head 62 is provided on a part of the side wall of the sub ink tank 28. The ink supply head 62 is provided with a positioning port 72.

  Here, as shown in FIG. 5, the ink supply head 62 includes an exhaust port 66 having an exhaust port 64 through which the air in the sub ink tank 28 can be discharged, and a sub port below the exhaust port 66. An ink replenishing port 70 having an ink replenishing port 68 capable of replenishing ink into the ink tank 28 is provided.

  As shown in FIG. 3, an exhaust valve 74 is provided inside the exhaust port 64 of the ink supply head 62, and a supply valve 76 is provided inside the ink supply port 68. Further, on the side wall of the sub ink tank 28, an exhaust hole 78 is provided in a portion facing the exhaust port 64 of the ink supply head 62, and an ink supply hole 80 is provided in a portion facing the ink supply port 68.

  The exhaust valve 74 is normally closed so that air inside the sub ink tank 28 does not flow out. However, when a connector (not shown) enters the exhaust port 64 and is connected to the exhaust valve 74 when ink is supplied, the exhaust valve 74 is exhausted. The valve 74 is opened, and the air inside the sub ink tank 28 can be exhausted through the exhaust hole 78.

  Similarly, the replenishing valve 76 is normally closed so that the air inside the sub ink tank 28 does not flow out, but a connector (not shown) enters the ink replenishing port 68 and is connected to the replenishing valve 76 when ink is replenished. Then, the supply valve 76 is opened, and ink can be supplied into the sub ink tank 28 through the ink supply hole 80.

  Here, as shown in FIG. 1, an ink replenishing device 82 having four ink replenishing units 84 for replenishing ink corresponding to each of the sub ink tanks 28 is attached to the main body housing 24. A position where ink can be supplied to the sub ink tank 28 by the ink supply unit 84 is referred to as an ink supply position of the sub ink tank 28. The ink supply position is also detected by the position sensor 22 in the same manner as the home position. The ink replenishment position may be the same position as the home position, but is a different position in this embodiment.

  Further, as shown in FIG. 5, a main ink tank 86 is disposed below the ink supply device 82. Ink used in the inkjet printer 10 is stored in the main ink tank 86 in advance, and this ink is supplied to the sub ink tank 28 by the ink supply device 82 and used for image recording. The main ink tank 86 is disposed so as to partially overlap the ink replenishing device 82 (substantially entirely in the present embodiment) when viewed in a plan view, and the ink jet printer 10 as a whole is miniaturized.

  The ink supply device 82 includes a fixed frame 88 that is integrally fixed to the main body housing 24 of the ink jet printer 10, and a guide frame 90 is disposed in the fixed frame 88. A predetermined gap is formed in the width direction between the fixed frame 88 and the guide frame body 90, and the guide frame body 90 is in the same direction as the movement direction (main scanning direction) of the carriage 14 in the fixed frame 88. It can move within a certain range. In the following description, the term “width direction” simply refers to the same direction as the width direction of the guide frame 90. This “width direction” coincides with the main scanning direction (arrow M direction) of the carriage 14.

  A pair of positioning arms 92 is provided in the vicinity of both ends in the width direction of the guide frame 90 so as to be slidable toward the carriage 14. The positioning arm 92 is in a position where it does not come into contact with the carriage 14 in a normal state, and performs ink replenishment positioning in the width direction by guiding the carriage 14 when refilling ink. As a result, the four ink supply units 84 are also integrally positioned with respect to the corresponding sub ink tank 28.

  In the guide frame 90, ink supply units 84 are disposed corresponding to the four sub ink tanks 28. Here, as shown in FIG. 6, the ink replenishment unit 84 slides independently inside the accommodating portion 94 provided in the guide frame 90 so as to approach and separate from the corresponding sub ink tank 28. It has become.

  As shown in FIG. 5, an exhaust connector 96 is provided on the surface of each ink supply unit 84 facing the sub ink tank 28 at a position corresponding to the exhaust port 64 of the sub ink tank 28. An ink supply connector 98 is provided at a position corresponding to the ink supply port 68 of the sub ink tank 28. Then, when the ink supply unit 84 moves toward the sub ink tank 28, the exhaust connector 96 is connected to the exhaust port 64, and the ink supply connector 98 is connected to the ink supply port 68.

  Each ink supply unit 84 has a cap 100 attached at a position corresponding to the pressure release port 42 of the housing 32 located above the sub ink tank 28.

  After the ink supply unit 84 approaches the sub ink tank 28, the exhaust connector 96 is connected to the exhaust port 64, and the ink supply connector 98 is connected to the ink supply port 68, the ink supply unit 84 is further connected to the sub ink tank 28. The cap 100 seals the pressure release port 42 by approaching. Here, the shape, mounting position, and the like of the cap 100 are set so as to prevent the air flow between the inside and the outside of the sub ink tank 28.

  As shown in FIG. 6, a positioning pin 102 protrudes from the ink supply unit 84 toward the sub ink tank 28. On the other hand, in the sub ink tank 28, the aforementioned positioning port 72 is arranged at a position corresponding to the positioning pin 102. The positioning pin 102 includes a columnar positioning portion 104 having a constant outer diameter, and a guide portion 106 formed in a tapered cone shape on the tip side of the positioning portion 104. The outer diameter is substantially equal to the inner diameter of the positioning port 72.

  When the ink supply unit 84 approaches the sub ink tank 28, first, the guide portion 106 on the distal end side of the positioning pin 102 enters the positioning port 72. Since the guide portion 106 is tapered, the positioning pin 102 enters the positioning port 72 even if the center of the positioning pin 102 and the center of the positioning port 72 are shifted.

  Then, as the ink supply unit 84 further approaches the sub ink tank 28, the guide portion 106 gradually moves in the direction in which the center of the positioning pin 102 and the center of the positioning port 72 coincide. When the positioning portion 104 reaches the positioning port 72, the center of the positioning pin 102 and the center of the positioning port 72 coincide with each other, and the ink supply unit 84 and the sub ink tank 28 are individually positioned. .

  An ink amount sensor 108 for detecting the ink amount inside is attached to the sub ink tank 28. The ink amount sensor 108 sends information on the detected ink amount in the sub ink tank 28 to the control circuit 44 (see FIG. 4).

  A guide pin 110 projects from each surface of the ink supply unit 84 and is accommodated in a guide groove 112 provided on the inner wall of the guide frame 90.

  As shown in FIG. 5, one end of an ink supply tube 114 is connected to the rear end of the ink supply connector 98. The other end of the ink supply tube 114 is connected to a main ink tank 86 in which ink used for image recording is stored in advance. When the ink supply connector 98 is connected to the ink supply port 68 of the sub ink tank 28, an ink flow path from the main ink tank 86 to the sub ink tank 28 is formed.

  The exhaust connector 96 and the exhaust port 64 shown in FIG. 5 are for discharging the air inside the sub ink tank 28, and ink does not flow through the inside.

  A cam unit 116 that rotates with a rotational force transmitted by a driving device (not shown) is arranged on the fixed frame 88 so as to correspond to the ink supply unit 84 and the positioning arm 92 and rotate coaxially and integrally. Has been. Each cam unit 116 includes a forward cam 118 for advancing the corresponding ink supply unit 84 or positioning arm 92 and a backward cam 120 for retreating.

  A cam follower unit 122 is disposed on the fixed frame 88. The cam follower unit 122 is integrally provided with a forward cam follower 124 and a backward cam follower 126 corresponding to the forward cam 118 and the backward cam 120, respectively, and can slide in the same direction as the sliding direction of the ink supply unit 84. It is said that.

  Further, the fixed frame 88 includes a link mechanism portion that includes a support shaft 128, a link 130 that can swing around the support shaft 128, and a displacement arm 132 that is pivotally supported at one end at the tip of the link 130. 134 is provided. The other end of the displacement arm 132 is pivotally supported by the positioning arm 92 or the ink supply unit 84.

  A cam follower unit 122 is pivotally supported at the approximate center of the link 130. As a result, when the cam follower unit 122 slides, the slide amount is amplified by the link mechanism unit 134 and transmitted to the positioning arm 92 or the ink supply unit 84.

  The positions and shapes of the forward cam 118 and the backward cam 120 are determined so that each cam unit 116 can advance or retract the corresponding positioning arm 92 or ink supply unit 84 at a predetermined timing. . In addition, a sensor (not shown) for detecting the rotational position of the cam unit 116 is attached to the fixed frame 88. Based on the rotational angle of the cam unit 116 detected by the sensor, the control circuit 44 (see FIG. 4). Is driven by a driving device (not shown) to set the initial position of the cam unit 116 and to control the rotation angle.

  As shown in FIG. 5, a pump unit 138 is provided corresponding to the exhaust tube 136 extending from each ink supply unit 84. The pump unit 138 is configured to include four roller pumps 140. Each roller pump 140 includes a pump shaft 142, a rotating plate 144 that rotates integrally with the pump shaft 142, and one or a plurality (two diagonally in this embodiment) arranged near the outer periphery of the rotating plate 144. ) Roller 146. On the other hand, the exhaust tube 136 is arranged so as to partially surround the periphery of the rotating plate 144, and the roller 146 locally crushes the exhaust tube 136.

  Therefore, when the rotating plate 144 rotates in the clockwise direction in FIG. 5, the roller 146 moves so as to squeeze the exhaust tube 136, and fluid (air in this embodiment) in the exhaust tube 136 is exhausted. To the atmosphere from the other end.

  In addition, each roller pump 140 has an attachment angle of each rotary plate 144 so that the rollers 146 are arranged at equal intervals as a whole when viewed along the axial direction of the pump shaft 142. As a result, resistance acting on the pump unit 138 (particularly, rotational resistance caused by the roller 146 being pushed by the reaction force of the exhaust tube 136) is dispersed, and the pump unit 138 rotates smoothly.

  The forward and backward movement of the ink supply unit 84 and the driving of the pump unit 138 are controlled by the control circuit 44 (see FIG. 4) so that the timing does not overlap with the maintenance operation in the maintenance station 20.

  Next, the operation of the first embodiment of the present invention will be described.

  When an operation signal (not shown) such as an operation panel or a personal computer is transmitted to the control circuit 44 in the inkjet printer 10, the control circuit 44 controls each part in the inkjet printer 10 based on the operation signal.

  Image recording by the inkjet printer 10 is performed in the following order.

  First, the recording medium P is conveyed to the lower part of the droplet discharge head 30, and then the carriage 14 is in the main scanning direction while the droplet discharge head 30 discharges droplets according to image information. Moving in the sub-scanning direction, the image is recorded on the recording medium P.

  Ink supply to the sub ink tank 28 of the inkjet printer 10 is performed in the following order.

  When ink is supplied from the sub ink tank 28 to the droplet discharge head 30 along with image recording, the ink in the sub ink tank 28 decreases. When the ink amount sensor 108 detects that the ink in the specific sub ink tank 28 has decreased to a predetermined amount and sends the information to the control circuit 44, the control circuit 44 moves the carriage 14 to the ink supply position. At this time, the control circuit controls so that the maintenance station 20 side does not operate.

  Next, the control circuit 44 drives a drive device (not shown) to rotate the cam unit 116 by an angle corresponding to the specific sub ink tank 28. Accordingly, the four ink supply units 84 are integrally positioned with respect to the corresponding sub ink tank 28.

  Since the guide portion 106 at the tip of the positioning pin 102 is tapered, when the positioning pin 102 is inserted into the positioning port 72, the center of the positioning pin 102 and the center of the positioning port 72 are shifted. In addition, the positioning pin 102 enters the positioning port 72. At this time, since the guide pin 110 has reached the wide portion of the guide groove 112 and a gap is formed between the guide pin 110 and the wide portion of the guide groove 112, the ink supply unit 84 is moved in the vertical direction and the width direction. It can move within a certain range.

  When the ink supply unit 84 further approaches the sub ink tank 28, the guide unit 106 gradually moves in a direction in which the center of the positioning pin 102 and the center of the positioning port 72 coincide. When the positioning unit 104 reaches the positioning port 72, the center of the positioning pin 102 and the center of the positioning port 72 coincide with each other, and the specific ink supply unit 84 and the corresponding sub ink tank 28 are accurately located. Positioned.

  The position of the ink supply unit 84 is the ink supply position, and the connection between the ink supply connector 98 and the ink supply port 68 of the sub ink tank 28 is completed and connected, and the main ink tank 86 is connected to the sub ink tank 28 (Bk). The ink flow path is configured. At the same time, the connection between the exhaust port 66 and the exhaust port 64 is also completed. Thereafter, as shown in FIG. 6, the cap 100 seals the pressure release port 42, thereby preventing air from flowing between the inside and the outside of the sub ink tank 28.

  Here, since the roller pump 140 constituting the pump unit 138 is driven by the control circuit 44 while the position of the ink supply unit 84 (Bk) is held at the ink supply position, the ink supply unit 84 (Bk) The internal air is discharged from the exhaust port 64 of the sub ink tank 28 (Bk).

  At this time, the pressure release port 42 of the housing 32 on the sub ink tank 28 (Bk) is sealed by the cap 100, so that air is inadvertently passed through the pressure release port 42 and the atmosphere communication port 48. It does not enter (Bk), and it can be surely exhausted from the sub ink tank 28 (Bk).

  In addition, the corresponding roller pump 140 is driven for the ink replenishing unit 84 of the other color that has not advanced at the ink replenishing position 82, but the exhaust connector 96 is open, so that the roller pump 140 is opened. There is no resistance in driving.

  The control circuit 44 drives a driving device (not shown) for a predetermined time, so that a predetermined amount of ink is supplied to the sub ink tank 28. The same operation is performed for colors other than Bk.

  Thus, when the replenishment of ink to the desired sub ink tank 28 is completed, the positioning arm 92 is retracted and returned to the initial position. Thus, all the operations for supplying ink to the sub ink tank 28 are completed.

  The humidification operation of the inkjet printer 10 is performed in the following order.

After the image recording, the control circuit 44 moves the carriage 14 to the home position. At the same time as reaching the home position, the control circuit 44 applies a voltage of about 3 V between the first electrode 59A and the second electrode 59B of the power source 58. By applying voltage, the porous positive electrode 54 proceeds with a decomposition reaction of water (H ₂ O) in the atmosphere (the above-mentioned reaction formula A). In the porous negative electrode 56, water (H ₂ O) generation reaction (the above-described reaction formula B) proceeds.

  The inside of the housing 32 is humidified by water (water vapor) generated by the porous negative electrode 56, and a part of the water vapor in the housing 32 flows into the sub ink tank 28 through the air communication port 48. The water vapor flowing into the sub ink tank 28 humidifies the ink inside the sub ink tank 28.

  The electric power supplied to the humidifying unit 36 can always be supplied by using a commercial AC power supply and the internal battery 203 (see FIG. 1) provided inside the inkjet printer 10.

  FIG. 14 is a block diagram showing the supply of electric power from the power source to the humidifying unit 36.

  Usually, power for driving the inkjet printer 10 is supplied from a commercial AC power supply 205. When connected to the commercial AC power source 205 and being capped, the humidifying unit 36 is supplied with rectified and stepped down power from the commercial AC power source 205. As long as the commercial AC power supply 205 is connected even when the ink jet printer 10 is turned off, the humidifying unit 36 is supplied with electric power.

  By the way, when the inkjet printer 10 is not used for a long time, the power cord is often disconnected from the commercial AC power source 205. At that time, the power source selection circuit 207 selects the internal battery 203, the humidification unit 36 and the minimum necessary control circuit can be operated by the power of the internal battery 203, and the inside of the housing 32 can always be humidified. .

  As the internal battery 203, a storage battery, a solar battery, a fuel cell, or the like is used.

  The storage battery is charged when it is connected to the commercial AC power source 205, and discharged when the power cord is disconnected, and supplies power to the humidifying unit 36. By repeating this, it is possible to constantly humidify the housing 32 as long as the power consumed in the long unused period does not exceed the power capacity of the storage battery.

  The solar cell can supply electric power as long as light strikes a panel provided on the outer wall of the inkjet printer 10. Furthermore, by using it together with a storage battery, it is possible to supply electric power even during periods of no light, such as at night. There is an effect that the capacity of the storage battery can be reduced as compared with the case where power is supplied only by the storage battery.

  A fuel cell is a small battery that can supply power for a long time. Furthermore, water is generated as a by-product that generates electric power.

  Note that batteries other than those listed above can be used as the internal battery 203 as long as they can supply necessary power over a long period of time.

  Here, the humidification operation works excessively, a signal is transmitted from the humidity sensor (not shown) to the control circuit 44, and the control circuit 44 changes the polarity of the applied voltage to the porous positive electrode 54 and the porous negative electrode 56. Then, the inside of the housing 32 is dehumidified.

  Thereby, since the ink in the sub ink tank 28 can be permanently moisturized, it is difficult for the ink to thicken.

  As described above, in the first embodiment of the present invention, since the inside of the sub ink tank 28 is constantly moisturized while being energized, it is possible to maintain an optimum state for droplet discharge, and a droplet discharge abnormality occurs. At the same time, a high-quality image can be recorded on the recording medium P.

  2nd Embodiment of the humidification mechanism of the liquid tank of this invention is described based on drawing.

  Note that components that are basically the same as those in the first embodiment described above are given the same reference numerals as those in the first embodiment, and descriptions thereof are omitted.

  FIG. 7 shows moving means 148 according to claim 2 of the present invention.

  The moving means 148 includes a first slide part 150, a second slide part 152, a support base 154, and a driving device (not shown).

  The first slide portion 150 is provided with a first slide plate 156, a first rack 158, a first gear 160, and a holding roller 162.

  The material and surface roughness of the first slide plate 156 are selected so that the surface has a low frictional force, and supports the housing 33. Further, the first slide plate 156 moves along a first guide 168 provided on the support base 154 so that the housing 33 can come into contact with and separate from the atmosphere communication head 34.

  Further, a pair of first racks 158 are formed on the first slide plate 156 in parallel with the first guide 168. A first gear 160 is engaged with the first rack 158.

  The atmosphere communication head 34 is provided with an atmosphere communication port 49.

  The first gear 160 is fixed to both ends of the first shaft 164, and both end portions of the first shaft 164 passing through the first gear 160 are supported by a support plate (not shown). The first gear 160 is applied with a rotational force by a driving device (not shown), and moves the first slide plate 156 and the housing 33 toward the atmosphere communication head 34. The first gear 160 also serves as a presser for the first slide plate 156 against the support base 154 fixed to the main body housing 24 (see FIG. 1).

  Here, the control circuit 44 can control the humidification in the housing 33 by the humidification unit 36 and the drive control of the drive unit in conjunction with each other.

  Further, the holding roller 162 presses the first slide plate 156 from above so that the first slide plate 156 does not float from the support base 154.

  The support base 154 is fixed to the main body housing 24 (see FIG. 1).

  The second slide part 152 is provided with a second slide plate 170, a second rack 172, and a second gear 174.

  The second slide plate 170 is movably mounted on the first slide plate 156, and movement in the width direction (short direction) is restricted by the second guide 178.

  Further, the material and surface roughness of the second slide plate 170 are selected so that the surface has a low frictional force, and a second rack 172 is provided at the center in the width direction. A second gear 174 is engaged with the second rack 172.

  Further, a support plate 176 is erected at the end of the second slide plate 170 at a position facing the pressure release port 43 of the housing 33.

  The second gear 174 is fixed to the second shaft 180, and both end portions of the second shaft 180 penetrating the second gear 174 are supported by a support plate. The second gear 174 is applied with a rotational force by the drive unit, and moves the second slide plate 170 toward the atmosphere communication head 34, and the second gear 174 is second with respect to the pressure release port 43 of the housing 33. A support plate 176 of the slide plate 170 can be contacted and separated. The second gear 174 also serves as a presser for the second slide plate 170 against the support base 154 fixed to the main body housing 24 (see FIG. 1).

  Here, as shown in FIG. 8, a connecting portion 182 is provided on the side surface of the housing 33 at a position facing the atmosphere communication port 49 (see FIG. 7) of the atmosphere communication head 34. The connecting portion 182 is fixed by fitting and bonding a hole formed in the central portion of a disk-shaped rubber plate into a hole (not shown) provided in the side wall of the housing 33.

  As shown in FIG. 9, a sealing plate 184 is provided on the surface of the support plate 176 facing the pressure release port 43 of the housing 33. The sealing plate 184 is made of a silicon rubber plate, and is bonded and fixed to the support plate 176.

  Next, the operation of the second embodiment of the present invention will be described.

  When the atmosphere communication port 49 of the sub ink tank 28 is humidified, the control circuit 44 rotates the first gear 160, the first slide plate 156 moves to the sub ink tank 28 side, and the connecting portion 182 of the housing 33 is moved. The sub-ink tank 28 is connected to the atmosphere communication port 49.

  At the same time that the connecting portion 182 is connected to the atmosphere communication port 49, a voltage is applied to the humidifying unit 36 by the control circuit 44 and the power source 58, and the inside of the housing 33 is humidified. The water supplied into the housing 33 passes through the atmosphere communication port 49 as water vapor and reaches the sub ink tank 28 to increase the humidity inside the sub ink tank 28.

  On the other hand, when the humidification of the air communication port 49 of the sub ink tank 28 is finished, the voltage application to the humidification unit 36 by the control circuit 44 and the power source 58 is stopped, and at the same time, the first gear 160 is rotated clockwise in FIG. And the first slide plate 156 is separated from the sub ink tank 28.

  When ink is supplied from the main ink tank 86 to the sub ink tank 28, first, the first gear 160 is rotated counterclockwise by the control circuit 44, and the first slide plate 156 is moved to the sub ink tank 28 side. By moving, the connecting portion 182 of the housing 33 is connected to the atmosphere communication port 49 of the sub ink tank 28.

  Subsequently, the second gear 174 is driven to rotate counterclockwise by the control circuit 44, the second slide plate 170 moves to the housing 33 side, and the sealing plate 184 provided on the second slide plate 170 is moved to the housing 33. The pressure release port 43 is sealed.

  Further, the ink supply unit 84 is connected to the ink supply head 62 of the sub ink tank 28, and the pump unit 138 operates to supply ink from the main ink tank 86 to the sub ink tank 28 together with the exhaust inside the sub ink tank 28. Is done. At this time, since the pressure release port 43 of the housing 33 is sealed, the negative pressure in the sub ink tank 28 does not decrease due to air leakage, and ink can be supplied stably.

  As described above, in the second embodiment of the present invention, the connecting portion 182 can be attached to and detached from the atmosphere communication port 49 depending on whether or not humidification is necessary. The internal pressure can be released directly from the atmosphere communication port 49 by detaching the part 182 from the atmosphere communication port 49.

  Further, the control circuit 44 and the power source 58 apply a voltage to the humidifying unit 36 when the connecting portion 182 is connected to the atmosphere communication port 49, so that unnecessary power is not wasted and energy saving can be achieved. .

  3rd Embodiment of the humidification mechanism of the liquid tank of this invention is described based on drawing.

  Note that components that are basically the same as those in the first embodiment described above are given the same reference numerals as those in the first embodiment, and descriptions thereof are omitted.

  As shown in FIG. 10, a fixed wall 186 is provided in a part of the main body housing 24 (see FIG. 1). The housing 35 has a surface opposite to the surface on which the humidifying unit 36 is provided fixed to the fixed wall 186. The fixing position of the housing 35 is substantially the center of the main scanning range in which the carriage 14 moves.

  A relay tube 188 is connected to the atmosphere communication port 49 (see FIG. 7) in the atmosphere communication head 34 on the sub ink tank 28. The relay tube 188 is a flexible hollow tube made of rubber or vinyl, and can be bent freely. One end of the relay tube 188 is branched according to the number of sub ink tanks 28 (188A, 188B, 188C, 188D). The other end of the relay tube 188 is connected to the housing 35, and communicates from the inside of the housing 35 to the atmosphere communication port 49 via the relay tube 188.

  Further, the length of the relay tube 188 is set to be more than half of the main scanning range in which the carriage 14 moves, and the carriage 14 remains connected to the atmosphere communication port 49 while the carriage 14 is connected to the main tube. It can move in the scanning direction.

  As shown in FIG. 11, a pressure release port 45 is provided on the lower surface of the housing 35. Here, as shown in FIG. 10, a moving base 190 is provided at a position facing the surface of the housing 35 where the pressure release port 45 is provided, and the moving base 190 is driven by a driving device (not shown). The housing 35 can move in a direction in which the pressure release port 45 of the housing 35 is in contact with or separated from. A sealing plate 185 is fixed to the surface of the moving base 190 that faces the pressure release port 45.

  Next, the operation of the third embodiment of the present invention will be described.

  In FIG. 10, a voltage is applied to the humidifying unit 36 by the control circuit 44 (see FIG. 4), and water is generated and humidified inside the housing 35. A part of the water generated in the housing 35 becomes water vapor and passes through the relay tube 188 and reaches the atmosphere communication port 49 (see FIG. 7). Further, the water vapor passes through the air communication port 49 and enters the sub ink tank 28 to humidify the sub ink tank 28.

  Here, even when the inkjet printer 10 starts image recording or the like and the carriage frame 26 moves over the entire main scanning direction, the relay tube 188 has a sufficient length, and the air communication port 49 or the housing The relay tube 188 is not detached from the 35. Further, since the relay tube 188 is freely bent in accordance with the moving direction of the carriage frame 26, the relay tube 188 is not crushed and can always pass water vapor.

  When the sub ink tank 28 is replenished with ink from the main ink tank 86 (see FIG. 5), the moving base 190 is moved by the control circuit 44 (see FIG. 4), and the sealing plate 185 is moved to the housing 35. The pressure release port 45 is sealed, and the ink supply operation is started. Thereby, the pressure inside the sub ink tank 28 is stabilized, and ink can be replenished stably.

  As described above, in the third embodiment of the present invention, even if the housing 35 is fixed at a specific location, the inside of the sub ink tank 28 is humidified through the relay tube 188, so that the installation position of the housing 35 can be freely set. Therefore, various layouts of the components inside the inkjet printer 10 are possible.

  4th Embodiment of the humidification mechanism of the liquid tank of this invention is described based on drawing.

  Note that components that are basically the same as those in the first embodiment described above are given the same reference numerals as those in the first embodiment, and descriptions thereof are omitted.

  As shown in FIG. 12, a waste droplet tank 192 is provided so as to cover the humidifying unit 36.

  Here, as shown in FIG. 13, an inner pressure release hole 194 is provided in the wall of the waste droplet tank 192, and the housing 37 is disposed in the waste droplet tank so that the internal pressure release hole 194 and the pressure release port 47 communicate with each other. It is fixed to the inner wall of 192. Here, the surface of the humidifying unit 36 is provided so as to face the inside of the waste droplet tank 192.

  Further, a moving base 191 is provided so as to be able to contact and separate from the internal pressure release hole 194, and a sealing plate 187 is provided on the moving base 191.

  As shown in FIG. 12, a droplet absorbing felt 196 for absorbing droplets is provided inside the waste droplet tank 192. The inside of the waste droplet tank 192 is sealed and is shielded from the outside air. Further, a relay member connecting portion 198 is provided on the upper surface of the waste droplet tank 192, and the housing 37 and the relay tube 188 are connected through the relay member connecting portion 198.

  Further, a waste liquid droplet transport pipe 200 is provided for the waste liquid droplet tank 192. The waste liquid droplet transport pipe 200 is connected to the waste liquid droplet tank 192 at a transport pipe connecting portion 202 provided on the upper surface of the waste liquid droplet tank 192. ing.

  Here, the waste droplets sucked by a droplet suction means (not shown) reach the waste droplet tank 192 through the waste droplet transport pipe 200 and are stored.

  Next, the operation of the fourth exemplary embodiment of the present invention will be described.

  The waste droplets sucked by the droplet suction means (not shown) reach the waste droplet tank 192 through the waste droplet transport pipe 200. The waste droplets that have reached the waste droplet tank 192 are absorbed by the droplet absorption felt 196.

  Water vapor generated from the waste droplets in the droplet absorption felt 196 stays inside the sealed waste droplet tank 192.

  Here, when a voltage is applied to the humidifying unit 36 by the control circuit 44 (see FIG. 4), water is generated in the humidifying unit 36 and the inside of the housing 37 is humidified. The humidity per unit volume in the waste droplet tank 192 is higher than the humidity per unit volume in the atmosphere, and the moisture in the waste droplet can be used effectively and humidified. Further, the housing 37 and the waste droplet tank 192 are integrated, and it is not necessary to provide them at different positions.

  When the sub ink tank 28 is supplied with ink from the main ink tank 86 (see FIG. 5), the moving base 191 is moved by the control circuit 44, and the sealing plate 187 seals the internal pressure release hole 194. Then, the ink supply operation is started. Thereby, the pressure inside the sub ink tank 28 is stabilized, and ink can be replenished stably.

  As described above, in the fourth embodiment of the present invention, since the housing 37 and the waste droplet tank 192 are integrated, space saving can be achieved.

  A fifth embodiment of a cap mechanism for a droplet discharge head according to the present invention will be described with reference to the drawings.

  Note that components that are basically the same as those in the first to fourth embodiments described above are given the same reference numerals as in the first to fourth embodiments, and descriptions thereof are omitted.

  As shown in FIG. 15, a fuel cell unit 204 is provided inside the inkjet printer 10 (see FIG. 1). The fuel cell unit 204 applies a voltage to the humidification unit 36 by power generation.

  Further, a water supply path 206 is provided for supplying water generated by power generation in the fuel cell unit 204 to a water storage tank 193 that covers the humidification unit 36. Thereby, the water generated by the power generation of the fuel cell unit 204 reaches the water storage tank 193.

  Next, the operation of the fifth exemplary embodiment of the present invention will be described.

  Waste droplets sucked by a droplet suction means (not shown) reach the water storage tank 193 through the waste droplet transport pipe 200.

  Further, the water generated by the power generation of the fuel cell unit 170 passes through the water supply path 206 and reaches the water storage tank 193. Waste droplets reaching the water storage tank 193 or water generated by the fuel cell unit 204 are absorbed by the droplet absorption felt 196.

  The waste droplets in the droplet absorbing felt 196 or the water vapor generated from the water generated by the fuel cell unit 204 stays inside the sealed water storage tank 193.

  Here, when a voltage is applied to the humidification unit 36 by the fuel cell unit 204, the decomposition reaction of water vapor inside the water storage tank 193 proceeds at the porous positive electrode 54 (see FIG. 3) of the humidification unit 36, and the porous Water generation reaction proceeds at the negative electrode 56 (see FIG. 3), and the inside of the housing 37 is humidified.

  Thus, in the fifth embodiment of the present invention, when the humidifying unit 36 is driven by the fuel cell unit 204, the water vapor in the water storage tank 193 is further selectively supplied into the housing 37, Can be maintained at high humidity.

  In addition, this invention is not limited to said embodiment.

  For example, an ink jet printer that does not have the main ink tank 86 and supplies ink directly from the sub ink tank 28 may be used.

  The housing 32, 33, 35, 37 may be made of a metal material such as stainless steel. Similarly, the ink supply tube 114 and the exhaust tube 136 are made of stainless steel except for a part of the pump unit 138. You may use metal pipes, such as.

  The polymer electrolyte membrane 52 may be a ceramic solid electrolyte that can be used at room temperature, and the porous positive electrode 54 and the porous negative electrode 56 contain a metal having a catalytic effect other than the platinum group. May be.

  Installation of the humidifying unit 36 on the housing 32, 33, 35, 37 is not only performed by bonding or screwing on the outside of the housing 32, 33, 35, 37 but also on the side wall of the housing 32, 33, 35, 37. It may be fitted and fixed.

  Further, the moving means for bringing the housing 33 into and out of contact with the atmosphere communication port 49 may be a means other than driving by a gear, for example, a moving means by an actuator, an electromagnetic switch or the like.

  The housing 35 may be fixed to the carriage frame 26, and the relay member may be a metal pipe.

  Further, when the humidity inside the housing 33 becomes excessive, not only the polarity of the applied voltage is reversed to dehumidify, but also the applied voltage is set to 0 V and the housing 33 is left apart from the atmosphere communication port 49, and the housing 33 The humidity inside 33 may be lowered.

1 is a perspective view of an ink jet printer including an ink tank humidification mechanism according to a first embodiment of the present invention. It is a perspective view of the ink tank provided with the humidification mechanism which concerns on 1st Embodiment of this invention. It is sectional drawing of the ink tank provided with the humidification mechanism which concerns on 1st Embodiment of this invention. It is a principle diagram of the humidification mechanism of the ink tank according to the first embodiment of the present invention. 1 is a perspective view of an ink supply device in an ink jet printer according to a first embodiment of the present invention. 1 is a partial view of an ink supply device in an ink jet printer according to a first embodiment of the present invention. It is a perspective view of the moving means concerning a 2nd embodiment of the present invention. It is a perspective view of the housing which concerns on 2nd Embodiment of this invention. It is a partially broken perspective view of the housing which concerns on 2nd Embodiment of this invention. It is the figure which showed the relay member which connects the sub ink tank and housing which concern on 3rd Embodiment of this invention. It is an external view of the housing which concerns on 3rd Embodiment of this invention. It is a block diagram of the carriage frame and waste droplet tank which concern on 4th Embodiment of this invention. It is sectional drawing of the housing and waste liquid drop tank which concern on 4th Embodiment of this invention. 1 is a block diagram of a power supply system of an inkjet printer according to a first embodiment of the present invention. It is the perspective view which showed the fuel cell unit and water | moisture-content supply system of the inkjet printer which concerns on 5th Embodiment of this invention.

Explanation of symbols

10 Inkjet printer (droplet discharge device)
28 Sub-ink tank (liquid tank)
32 Housing (Housing)
33 Housing (Housing)
35 Housing (Housing)
36 Humidification unit (solid electrolyte membrane)
37 Housing (Housing)
38 Fixing member (frame part)
42 Pressure release port (pressure release port)
43 Pressure release port (pressure release port)
44 Control circuit (power supply means)
45 Pressure release port (pressure release port)
47 Pressure release port (pressure release port)
48 Air communication port (Atmospheric communication port)
49 Air communication port (Atmospheric communication port)
50 Vent (Vent)
52 Polymer electrolyte membrane (Polymer electrolyte membrane)
54 Porous anode (porous anode)
56 Porous negative electrode (Porous negative electrode)
58 Power supply (Power supply means)
148 Moving means (moving means)
182 connecting part (connecting part)
188 Relay tube (relay member)
192 Waste droplet tank (waste liquid tank)
193 Water storage tank (storage tank)
203 Internal battery (power supply means)
204 Fuel cell unit (second power supply means)
205 Commercial AC power supply (first power supply means)
206 Water supply path 207 Power supply selection circuit (power supply selection means)

Claims (12)

A housing having a vent hole communicating with the inside of the liquid tank, and a pressure release port for releasing the pressure inside the liquid tank;
A solid electrolyte membrane that constitutes part of the wall surface of the housing and uses hydrogen ions taken from outside as water molecules in the housing;
Power supply means for applying a voltage to the solid electrolyte membrane;
A humidifying mechanism for a liquid tank. A housing;
A connecting portion formed in the housing and connected to an air communication opening that opens the liquid tank to the atmosphere;
Moving means for attaching and detaching the connecting portion and the atmosphere communication port;
A solid electrolyte membrane that constitutes part of the wall surface of the housing and uses hydrogen ions taken from outside as water molecules in the housing;
Power supply means for applying a voltage to the solid electrolyte membrane;
A humidifying mechanism for a liquid tank.   The humidification mechanism for a liquid tank according to claim 2, wherein the power supply means applies a voltage to the solid electrolyte membrane when the connecting portion is connected to the atmosphere communication port. A housing;
A pressure release port provided in the housing;
A relay member for communicating between the atmosphere communication port for opening the inside of the liquid tank to the atmosphere and the inside of the housing;
A solid electrolyte membrane that constitutes part of the wall surface of the housing and uses hydrogen ions taken from outside as water molecules in the housing;
Power supply means for applying a voltage to the solid electrolyte membrane;
A humidifying mechanism for a liquid tank.   5. The liquid tank humidification mechanism according to claim 4, wherein the relay member is a flexible bendable tube.   6. The humidifying mechanism for a liquid tank according to claim 4, further comprising a waste liquid tank for storing the liquid waste liquid and covering the solid electrolyte membrane.   The humidification mechanism for a liquid tank according to any one of claims 1 to 6, wherein the solid electrolyte membrane is attached to an inner side of a frame portion protruding from a side wall of the housing.   The solid electrolyte membrane includes a polymer electrolyte membrane, a porous negative electrode provided on one side of the polymer electrolyte membrane facing the inside of the housing, and the other side of the polymer electrolyte membrane. The humidifying mechanism for a liquid tank according to any one of claims 1 to 7, wherein the humidifying mechanism comprises a porous positive electrode facing the outside of the housing.   9. The liquid according to claim 8, wherein the polarity of the voltage applied by the power supply means is changed, and the porous negative electrode is changed to a porous positive electrode, and the porous positive electrode is changed to a porous negative electrode. Tank humidification mechanism.   A liquid droplet ejection apparatus comprising the liquid tank humidification mechanism according to any one of claims 1 to 9. A first power supply means for supplying power from a commercial AC power supply;
Second power supply means for supplying electric power from a power supply provided inside the droplet discharge device;
The liquid droplet ejection apparatus according to claim 10, further comprising: a power source selection unit that switches between the first power source unit and the second power source unit according to a connection state to the commercial AC power source.   12. The droplet discharge device according to claim 11, wherein the second power supply means is a fuel cell, and includes a storage tank that covers the solid electrolyte membrane and stores water generated by the fuel cell.

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