JP2006272900A - Ink cartridge and inkjet recording system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an ink cartridge with no leakage of ink even when an impact or a vibration is applied. <P>SOLUTION: The ink cartridge 21 comprises an ink storing room 24 for storing the ink 23, an ink feeding part 26 for feeding the ink 23 to a recording head, and an open air introducing part 31 for introducing an open air into the ink storing room 24 in accordance with the change in pressure of the ink storing room 24 accompanied with consumption of the ink. The open air introducing part 31 is provided with two valves which are a primary valve 33 for opening and closing a primary introducing opening 32 and a secondary valve 52 for opening and closing a secondary introducing opening 51. As the primary valve 33 and the secondary valve 52 are stored in a main body 22, there exists no possibility of opening the valves carelessly. In addition, even when the secondary valve 52 is opened by applying the impact or the vibration and the ink 23 flows out to the open air introducing part 31, leakage to the outside can be prevented by the primary valve 33. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an ink cartridge that stores ink to be supplied to an ejection type recording head, and an ink jet recording system that uses the ink cartridge.

  2. Description of the Related Art A so-called ink jet recording apparatus is known that includes an ink ejection type recording head provided with an ejection port for ejecting ink, ejects ink as droplets from the recording head, and deposits the ink on a sheet to record an image. Yes. The ink jet recording apparatus is provided with an ink tank for storing ink, and ink is supplied from the ink tank to the recording head. The recording head includes, for example, a nozzle having a discharge port and a diaphragm driven by a piezo element, and sucks ink from an ink tank to the nozzle by using a pressure change caused by vibration of the diaphragm. Spray from the outlet.

  Since ink is a consumable item, in consideration of the convenience of replenishment, the ink tank is often of a cartridge type that is replaceably attached to the ink jet recording apparatus. This cartridge type ink tank (hereinafter referred to as an ink cartridge) is replaced with a new ink cartridge filled with ink when the ink is used up and becomes empty. An ink supply needle for supplying ink to the recording head is arranged in the cartridge mounting portion to which the ink cartridge is mounted. When the ink cartridge is mounted in the cartridge mounting portion, the ink supply needle is formed in the ink cartridge. Inserted into the ink supply port. Thereby, an ink supply path including an ink supply needle is established between the ink cartridge and the nozzle.

  In addition to the ink supply port, the ink cartridge is provided with an air introduction port for introducing air into the ink storage chamber. When the ink in the ink storage chamber is consumed by the recording head, the pressure in the ink storage chamber decreases. If this pressure decreases too much, the meniscus of the ink in the nozzle is destroyed, and the atmosphere flows from the nozzle outlet, causing a discharge failure. The air introduction port is for taking in air corresponding to the amount of ink consumed by the recording head into the ink storage chamber, and the pressure of the nozzle is maintained within a predetermined range by taking in the air.

In order to prevent the ink from being leaked outside from the ink supply port or the air introduction port when the ink cartridge in use that is not empty is removed from the ink jet recording apparatus, the ink supply port There is known an ink cartridge provided with two valves for sealing each of the air inlets (for example, see Patent Document 1 below). Each of these valves is biased to a closed position by a spring when the ink cartridge is removed from the ink jet recording apparatus, thereby preventing ink leakage.
JP 2004-243778 A

  However, in the ink cartridge described in Patent Document 1, since the movable part for opening the valve is exposed to the outside when the ink cartridge is mounted on the ink jet recording apparatus, during handling of the ink cartridge, If the movable part comes into contact with something, the valve may open carelessly. Further, the air inlet of the ink cartridge is not completely sealed, and the ink storage chamber is opened to the atmosphere through a filter made of a porous material and the air inlet. Therefore, there is a concern that ink leakage may occur through the air inlet when the filter itself is broken or when the ink meniscus contained in the filter gap is destroyed by impact.

  An object of the present invention is to provide an ink cartridge that does not leak ink even when an impact or vibration is applied, and an ink jet recording system that uses the ink cartridge.

  An ink cartridge according to the present invention includes a discharge-type recording head, and is detachably set in an ink jet recording apparatus that records an image by the recording head. The main body includes an ink storage chamber that stores ink supplied to the recording head. An ink cartridge comprising: an ink supply unit for supplying ink in the ink storage chamber to the recording head; and an air introduction unit that introduces air into the ink storage chamber according to the pressure in the ink storage chamber The atmosphere introduction unit sends a primary valve that opens and closes a primary introduction port that introduces the atmosphere into the atmosphere introduction unit from outside the main body, and sends the atmosphere introduced into the atmosphere introduction unit from the primary introduction port into the ink storage chamber. A secondary inlet and a secondary valve that opens and closes the secondary inlet are provided.

  It is preferable that the primary valve and the secondary valve are biased by a biasing member toward a closed position that closes each of the primary and secondary inlets, for example. The secondary valve is a magnet valve that can be opened and closed by an electromagnet.

  In the air introduction part, a part of the peripheral wall is formed of a flexible member in the introduction path from the primary introduction port to the secondary introduction port, and air flowing from the primary introduction port and the secondary introduction port A buffer chamber is preferably provided for receiving.

  The secondary valve opens when the pressure in the ink storage chamber rises above the pressure in the atmosphere introduction portion, and opens the secondary introduction port against the urging force of the urging member due to the pressure difference. It is preferable that the position can be moved.

  An ink jet recording system of the present invention includes an ink jet recording apparatus that includes a discharge type recording head and records an image by the recording head, and stores ink supplied to the ink jet recording apparatus. A main body having an ink storage chamber, an ink supply unit for supplying ink in the ink storage chamber to the recording head, and an air introduction unit for introducing air into the ink storage chamber according to the pressure in the ink storage chamber The ink cartridge includes: a primary valve that opens and closes a primary inlet formed in the atmosphere introduction unit; and the atmosphere introduced from the primary inlet is the ink storage chamber. A secondary inlet for feeding into the secondary inlet and a secondary valve for opening and closing the secondary inlet Ri, the inkjet recording apparatus is characterized by having two driving units for opening and closing the primary valve and the secondary valve independently.

  An ink jet recording apparatus 10 shown in FIG. 1 includes a recording head 12 that records an image by ejecting and adhering ink to a paper 11. The recording head 12 includes a plurality of nozzles in which ejection openings for ejecting ink are formed, and the ejection surface on which the ejection openings of the plurality of nozzles are arranged faces the recording surface of the paper 11. . The recording head 12 is attached to a carriage 13 that is movable in the width direction (main scanning direction X) of the paper 11, and the ejection surface is exposed from an opening formed on the bottom surface of the carriage 13. The recording head 12 performs line recording of an image while reciprocating along the width direction of the paper 11 as the carriage 13 moves. Each time the recording head 12 reciprocates once, the paper 11 is fed in the sub-scanning direction Y by a conveyance roller (not shown) by the recording width of the reciprocating movement of the recording head 12. These operations are repeated to record an image for one screen.

  The carriage 13 is slidably attached to the guide rods 14 a and 14 b and is driven by a belt mechanism 18 including a belt 16 and a pair of pulleys 17. For example, four ink cartridges 21 each containing four colors of Y, M, C, and K are removably attached to the carriage 13 above the recording head 12. Reference numeral 20 denotes a cover that is detachably attached to the carriage 13 and covers the mounted ink cartridge 21.

  A plurality of slots into which the ink cartridges 21 are inserted are formed in the carriage 13. Each of these slots is provided with a hollow ink supply needle 36 (see FIG. 2) in which a flow path for feeding ink to the recording head 12 is formed. When the ink cartridge 21 is inserted into the slot, the ink cartridge 21 is inserted. An ink supply needle 36 is inserted into an ink supply section 26 (see FIG. 2) provided at the bottom of the ink supply section. The ink stored in the ink cartridge 21 is supplied to the recording head 12 through the ink supply needle 36. The recording head 12 is provided with a vibration plate driven by a piezo element corresponding to each nozzle, and the ink in the ink cartridge 21 is sucked into the nozzle by the pressure change caused by the vibration of the vibration plate, and the ejection port Is injected from.

  As shown in FIG. 2, the ink cartridge 21 has an ink storage chamber 24 for storing ink 23 in a main body 22 formed of, for example, a plastic material. An ink supply unit 26 that supplies the ink 23 to the recording head 12 is provided at a position corresponding to the ink storage chamber 24 at the bottom of the main body 22.

  The ink supply unit 26 protrudes downward in a substantially cylindrical shape, and the protruding portion is fitted in the slot of the carriage 13. An ink supply port 27 into which the ink supply needle 36 enters is formed on the bottom surface of the ink supply unit 26. A supply valve 28 for opening and closing the ink supply port 27 is provided inside the ink supply unit 26. The supply valve 28 is provided movably between a closed position (indicated by a two-dot chain line in the figure) for closing the ink supply port 27 and an open position (indicated by a solid line in the figure) for opening the ink supply port 27. It is biased towards the closed position.

  For example, the outer peripheral surface of the supply valve 28 is formed of an elastic material such as rubber. When the supply valve 28 is in the closed position, the supply valve 28 is in close contact with the inner wall of the ink supply unit 26 to hermetically seal the ink supply port 27. To do. Since the supply valve 28 is stored in the ink supply unit 26, even if the vicinity of the ink supply port 27 of the ink supply unit 26 comes into contact with something while the ink cartridge 21 is being handled, the supply valve 28 is inadvertently opened. There is no.

  When the ink cartridge 21 is mounted on the carriage 13, the tip of the supply needle 36 comes into contact with the supply valve 28 and pushes the supply valve 28 to the open position against the bias of the spring 29. As a result, the ink in the ink storage chamber 24 flows into the ink supply unit 26 from the internal opening 30 and can be supplied to the recording head 12 through the ink supply needle 36. When the ink cartridge 21 is removed from the carriage 13, the supply valve 28 is moved to the closed position by the bias of the spring 29 and the ink supply port 27 is closed. Thereby, ink leakage from the ink supply port 27 is prevented.

  At the side end portion of the main body 22, an air introduction portion 31 is provided for introducing into the main body 22 the air that is sent to the ink storage chamber 24 in accordance with the decompression of the ink storage chamber 24 as ink is consumed. The ink storage chamber 24 and the air introduction part 31 are partitioned by a partition wall 38. When the ink storage chamber 24 is not attached (when the ink cartridge 21 is removed from the carriage 13), the ink storage chamber 24 is almost at atmospheric pressure, but immediately after the ink cartridge 21 is attached to the carriage 13, the ink jet recording apparatus 10 is used. Ink is sucked through the nozzles to a negative pressure (relative to the atmospheric pressure) by a suction device (not shown) provided in. In this way, the internal pressure of the discharge port of the nozzle connected to the ink storage chamber 24 through the ink supply needle 36 is set to a negative pressure, thereby preventing ink leakage from the discharge port.

  However, if the pressure in the ink storage chamber 24 becomes too low due to ink consumption, the meniscus of the ink in the nozzle is destroyed, and the atmosphere flows into the nozzle from its discharge port. The air that has flowed into the nozzle becomes a damper that absorbs pressure changes due to deformation of the piezoelectric element, causing non-ejection. In the case of a thermal recording head, the heat generating portion becomes empty and causes non-ejection. Furthermore, there is a possibility that the heat generating part may burn and cause kogation. Thus, since the pressure in the ink storage chamber 24 is problematic even if it is too low, it is necessary to maintain it within a specified range. For this reason, the atmosphere introduction unit 31 introduces the atmosphere into the ink storage chamber 24 to compensate for the pressure drop in the ink storage chamber 24 due to ink consumption. Thereby, the pressure in the ink storage chamber 24 is maintained within a specified range.

  As with the ink supply unit 26, the air introduction unit 31 has a bottom portion that protrudes downward in a substantially cylindrical shape, and the protruding portion fits into a slot of the carriage 13. On the bottom surface of the air introduction part 31, a primary introduction port 32 that introduces air into the atmosphere introduction part 31 from the outside of the main body 22 is formed. A primary valve 33 that opens and closes the primary inlet 32 is provided inside the air introduction part 31. The primary valve 33 is provided movably between a closed position (indicated by a solid line in the figure) for closing the primary introduction port 32 and an open position (indicated by a two-dot chain line in the figure) for opening the primary valve 32. It is biased towards the closed position.

  For example, when the outer peripheral surface of the primary valve 33 is formed of an elastic material such as rubber and is in the closed position, the primary valve 33 is in close contact with the inner wall of the air introduction portion 31 and hermetically seals the primary introduction port 32. . Since the primary valve 33 is stored in the atmosphere introduction unit 31, even if the vicinity of the primary introduction port 32 of the atmosphere introduction unit 31 comes into contact with something during the handling of the ink cartridge 21, the primary valve 33 opens carelessly. There is no.

  The ink jet recording apparatus 10 is provided with a pin 39 for opening and closing the primary valve 33. The pin 39 enters the air introduction part 31 from the primary introduction port 32 and comes into contact with the primary valve 33 to push it up to the open position against the bias of the spring 34. The pin 39 is driven by a pin drive mechanism 41 configured by, for example, a solenoid. The pin drive mechanism 41 is connected to the controller 42 of the inkjet recording apparatus 10 and drives the pin 39 in accordance with a command from the controller 42.

  The controller 42 opens and closes the primary valve 33 according to the pressure change in order to maintain the pressure in the ink storage chamber 24 within a specified range while the ink cartridge 21 is set on the carriage 13. The pressure in the ink storage chamber 24 is measured by, for example, a pressure sensor 44 provided near the nozzles of the recording head 12. The controller 42 determines the opening time of the primary inlet 32 based on the measurement value of the pressure sensor 44. The pin drive mechanism 41 drives the pin 39 so that the primary introduction port 32 is opened for the opening time. When the primary valve 33 is opened, the atmosphere enters the atmosphere introduction part 31 through the primary introduction port 32 and the internal opening 46.

  In this example, the pressure sensor is provided in the vicinity of the nozzle, but may be provided in the vicinity of the ink supply port, for example, within the ink supply path. Further, the pressure of the ink storage chamber may be estimated by counting the number of ejections of the nozzles without using the pressure sensor, and the opening time of the primary inlet may be determined accordingly.

  In addition, a secondary introduction port 51 through which the air introduced into the atmosphere introduction unit 31 from the primary introduction port 32 is sent to the ink storage chamber 24 is formed in the upper part of the partition wall 38. A filter 47 is provided on the ink storage chamber 24 side of the secondary introduction port 51. The filter 47 is made of, for example, a porous material, and allows the air flowing into the ink storage chamber 24 from the air introduction portion 31 to pass therethrough, and adsorbs dust and dirt contained in the air, so that the ink storage chamber Block entry to 24. The filter 47 prevents the ink from flowing out from the ink storage chamber 24 toward the air introduction part 31.

  The air introduction part 31 is provided with a secondary valve 52 for opening and closing the secondary introduction port 51. The secondary valve 52 is provided movably between a closed position (indicated by a solid line in the figure) for closing the secondary inlet 51 and an open position (indicated by a two-dot chain line in the figure) for opening it. 53 is biased toward the closed position. The secondary valve 52 is a magnet valve in which a magnet is embedded and an outer peripheral surface is covered with an elastic material such as rubber. When the secondary valve 52 is in the closed position, the secondary introduction port 51 is sealed in close contact with the wall surface of the partition wall 38 and the ink storage chamber 24 is sealed.

  Similar to the primary valve 33, the secondary valve 52 opens and closes according to a change in pressure in the ink storage chamber 24 due to ink consumption while the ink cartridge 21 is set on the carriage 13, and the secondary valve 52 opens to the atmosphere from the primary inlet 32. The air taken into the introduction part 31 is sent to the ink storage chamber 24 to adjust its internal pressure. The secondary valve 52 is driven by a valve drive unit 54.

  The valve drive unit 54 includes an electromagnet that generates a magnetic force having a polarity opposite to that of the magnet in the secondary valve 52 by power supply, and a circuit that supplies power to the electromagnet. When the valve drive unit 54 passes a current through the electromagnet, the electromagnet generates a magnetic force only during that time, and the secondary valve 52 moves to the open position against the bias of the spring 53. When the valve drive unit 54 turns off the power supply to the electromagnet, the secondary valve 52 returns to the closed position by the bias of the spring 53. The valve drive unit 54 is connected to the controller 42, and the controller 42 controls the opening timing and the opening time of the secondary valve 52 through the valve drive unit 54.

  Further, the secondary valve 52 also plays a role of releasing the air in the ink storage chamber 24 toward the atmosphere introduction unit 31 when the pressure of the ink storage chamber 24 is excessively increased due to, for example, a temperature rise. When the temperature of the air in the ink storage chamber 24 rises and the pressure increases, the air easily dissolves in the ink 23 and the amount of dissolved gas in the ink 23 increases. The dissolved gas is likely to be bubbled due to vibration accompanying the reciprocation of the carriage 13 and pressure change during ink suction by the recording head 12. If such ink 23 is supplied to the nozzles, it causes ejection failure.

  Further, when the ink cartridge 21 is attached to the carriage 13 in a state where the pressure in the ink storage chamber 24 is high, the pressure in the ink storage chamber 24 is released at the moment when the primary valve 33 is opened by the ink supply needle 36 and the internal opening is opened. Ink is ejected from 30, and in the worst case, ink is spilled to the outside from the ink supply port 27. Therefore, when the pressure in the ink storage chamber 24 increases excessively, the secondary valve 52 is opened against the biasing force of the spring 53 by the pressure. By doing so, the air in the ink storage chamber 24 is released to the atmosphere introduction portion 31 through the secondary introduction port 51, and the pressure in the ink storage chamber 24 is reduced. Thus, the secondary valve 52 is disposed so as to seal the secondary introduction port 51 from the atmosphere introduction unit 31 side so that the secondary valve 52 moves to the open position due to the pressure increase in the ink storage chamber 24. Has been.

  As described above, since the secondary valve 52 is opened by the pressure increase in the ink storage chamber 24, the biasing force of the spring 53 is relatively weak. Therefore, when the filter 47 itself is damaged by an external impact applied to the ink cartridge 21 or the ink meniscus contained in the gap of the filter 47 is destroyed, the secondary valve is caused by the impact. There is also concern that 52 will open. If the secondary valve 52 is opened, ink may leak from the secondary inlet 51. However, since the atmosphere introduction part 31 is provided with two valves, the primary valve 33 and the secondary valve 52, even if ink leakage occurs from the secondary introduction port 51, the primary valve 33 causes the outside of the main body 22 to be outside. Outflow to is prevented.

  In addition, the atmosphere introduction unit 31 is provided with a buffer chamber 56 that receives air flowing from the primary introduction port 32 and the secondary introduction port 51 in the atmosphere introduction path from the primary introduction port 32 to the secondary introduction port 51. Yes. A part of the peripheral wall of the buffer chamber 56 is formed of a flexible sheet 58, and the sheet 58 is bent according to the internal pressure so that the volume of the buffer chamber 56 changes. As a result, when the pressure in the ink storage chamber 24 rises and the secondary valve 52 is opened, the volume of the buffer chamber 56 expands due to the sheet 58 being bent outward, and the ink storage chamber 24. The air inside is taken in through the secondary inlet 51. Thereby, the excessive pressure in the ink storage chamber 24 is absorbed.

  The buffer chamber 56 also plays a role in relieving a sudden inflow of air into the ink storage chamber 24 when the ink cartridge 21 is removed from the carriage 13. As described above, the ink storage chamber 24 is set to a negative pressure by the suction device immediately after the ink cartridge 21 is mounted on the carriage 13, and the state is maintained while the ink storage chamber 24 is mounted on the carriage 13. However, if the ink cartridge 21 is removed from the carriage 13 in this state, the air flows from the ink supply port 27 into the ink storage chamber 24. When the atmosphere flows into the ink storage chamber 24, ink bubbles are generated and the air is easily dissolved into the ink. Furthermore, when an ink absorber that absorbs and holds ink by capillary force, such as a sponge, is stored in the ink storage chamber, the air into which the ink absorber flows in near the ink supply port is sucked. In this case, when the recording head 12 performs suction, ink is not supplied to the nozzle, and the air is sent into the nozzle. The inflow of air into the nozzle causes discharge failure as described above.

  Therefore, before the ink cartridge 21 is removed from the carriage 13, the ink jet recording apparatus 10 sends air to the ink storage chamber 24 through the air introduction unit 31 so that the ink storage chamber 24 is brought close to atmospheric pressure. This prevents the air from flowing from the ink supply port 27 into the ink storage chamber 24 when the ink cartridge 21 is removed.

  However, if the primary valve 33 and the secondary valve 52 are simultaneously opened in a state where the pressure in the ink storage chamber 24 is too low, the air suddenly flows into the ink storage chamber 24. Therefore, the primary valve 33 is opened earlier than the secondary valve 52, the buffer chamber 56 is once brought to atmospheric pressure, the primary valve 33 is then closed, and then the secondary valve 52 is opened, and the air in the buffer chamber 56 is opened. Is fed into the ink storage chamber 24. Thereby, the inflow of the atmosphere from the ink supply port 27 can be gently performed.

  The ink jet recording apparatus 10 is provided with a cover opening / closing detection sensor 61 that detects opening / closing of the cover 20. As the cover open / close detection sensor 61, for example, a sensor that outputs a signal having a level corresponding to the presence or absence of the cover 20 is used. Based on the signal from the cover open / close detection sensor 61, the controller 42 detects that the cover 20 has been removed from the carriage 13 and determines that the ink cartridge 21 removal preparation operation has started. Then, the primary valve 33 is opened for a predetermined time, and the atmosphere is introduced into the buffer chamber 56 from the primary introduction port 32 to bring the buffer chamber 56 to atmospheric pressure. After that, the secondary valve 52 is opened and the air in the buffer chamber 56 is sent into the ink storage chamber 24.

  Hereinafter, the operation of the above configuration will be described with reference to the table showing the valve open / closed state and pressure state shown in FIG. 3 and the flowchart showing the cartridge removal procedure shown in FIG. As shown in FIG. 3, first, before the ink cartridge 21 is mounted on the carriage 13, basically, the ink supply valve 28, the primary valve 33, and the secondary valve 52 are all in the closed position. The ink supply port 27, the primary introduction port 32, and the secondary introduction port 51 are all sealed. However, when the pressure in the ink storage chamber 24 is higher than that in the buffer chamber 56, the secondary valve 52 is automatically opened due to the pressure difference, and the pressure in the ink storage chamber 24 is released to the buffer chamber 56. . With such pressure adjustment, the pressure states of the ink storage chamber 24 and the buffer chamber 56 are both close to atmospheric pressure.

  When the ink cartridge 21 is mounted on the carriage 13, the primary valve 33 is opened by the ink supply needle 36. Immediately after the mounting, the primary valve 33 and the secondary valve 52 remain closed. Then, the ink in the ink storage chamber 24 is sucked through the ink supply needle 36 by the suction device, and the ink storage chamber 24 is set to a negative pressure. At this time, the secondary valve 52 is opened momentarily, and the buffer chamber 56 is also set to a negative pressure. The ink cartridge 21 waits for printing in this state.

  When printing is started, the primary valve 33 and the secondary valve 52 are opened and closed according to the amount of ink used, and air is introduced so that the pressure in the ink storage chamber 24 does not drop too much, and the pressure is maintained within a specified range. Is done. When adjusting the pressure in the ink storage chamber 24 during printing, one valve is used by shifting the opening / closing timings of the two valves, the primary valve 33 and the secondary valve 52, or by changing the opening time. Compared to the case, finer pressure adjustment can be performed.

  Further, when the pressure in the ink storage chamber 24 increases due to the temperature rise, the secondary valve 52 opens and air escapes from the ink storage chamber 24 to the buffer chamber 56, so that the excess pressure in the ink storage chamber 24 is increased. Absorbed. For this reason, dissolution of gas in the ink 23 is suppressed. For this reason, it is possible to suppress the gas dissolved in the ink 23 from being bubbled again due to the vibration accompanying the reciprocating movement of the carriage 13 or the pressure fluctuation at the time of ink suction, and the ejection failure of the nozzle can be suppressed.

  When removing the ink cartridge 21 from the carriage 13, first, the cover 20 is removed from the carriage 13. As shown in FIG. 4, when the controller 42 detects that the cover 20 has been removed, the controller 42 determines that a preparation operation for removing the ink cartridge 21 has started, and first opens the secondary valve 52 for a predetermined time. As a result, the ink storage chamber 24 and the buffer chamber 56 communicate with each other through the secondary introduction port 51, and the air in the buffer chamber 56 is introduced into the ink storage chamber 24, thereby reducing the negative pressure in the ink storage chamber 24. The

  Then, after closing the secondary valve 52, the primary valve 33 is opened for a predetermined time. Since the buffer chamber 56 has a negative pressure, air is introduced from the primary inlet 32 into the buffer chamber 56. As a result, the buffer chamber 56 becomes atmospheric pressure. Thereafter, the primary valve 33 is closed and the secondary valve 52 is opened again for a predetermined time. As a result, the ink storage chamber 24 and the buffer chamber 56 communicate with each other through the secondary introduction port 51, and the air in the buffer chamber 56 is introduced into the ink storage chamber 24, so that the ink storage chamber 24 becomes close to atmospheric pressure. .

  In this state, the ink cartridge 21 is removed from the carriage 13. Since the ink storage chamber 24 is near atmospheric pressure, even if the ink supply needle 36 is pulled out from the ink supply port 27, the inflow of air from the ink supply port 27 to the ink storage chamber 24 is suppressed.

  Even when the pressure in the ink storage chamber 24 rises due to a rise in the temperature of the environment in which the removed ink cartridge 21 is stored, the secondary valve 52 opens and the buffer chamber 56 causes the excess pressure in the ink storage chamber 24 to be increased. Since it is absorbed, even when vibration is applied to the ink cartridge 21, the gas dissolution into the ink 23 is suppressed.

  Further, since the ink supply valve 26, the primary valve 33, and the secondary valve 52 are respectively stored in the main body 22, they are not opened carelessly due to an impact or the like. Further, even if the filter 47 is damaged by an impact or the like, the ink meniscus in the filter 47 is destroyed, and the ink 23 flows into the air introduction part 31, the primary valve 33 prevents leakage to the outside. Is done.

  In the above embodiment, an example of an ink cartridge in which only ink is stored in the ink storage chamber has been described. However, a sponge that absorbs and holds ink in the ink storage chamber and generates negative pressure by the action of its capillary force, etc. The negative pressure generating member may be accommodated.

It is explanatory drawing which shows schematic structure of an inkjet recording device. It is a block diagram of an ink cartridge. It is a table | surface which shows the valve open / close state and pressure state of an ink cartridge. 6 is a flowchart illustrating a procedure for removing an ink cartridge.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Inkjet recording device 11 Paper 12 Recording head 13 Carriage 21 Ink cartridge 22 Main body 24 Ink storage chamber 26 Ink supply part 27 Ink supply port 28 Supply valve 31 Atmospheric introduction part 32 Primary introduction port 33 Primary valve 51 Secondary introduction port 52 Secondary Valve 56 Buffer chamber

Claims (6)

A main body including an ink storage chamber that includes a discharge-type recording head and is detachably set in an ink jet recording apparatus that records an image by the recording head, and stores ink supplied to the recording head; An ink cartridge comprising: an ink supply unit for supplying ink to the recording head; and an air introduction unit that introduces air into the ink storage chamber according to a pressure in the ink storage chamber.
The air introduction part is a primary valve that opens and closes a primary inlet for introducing air from outside the main body into the air introduction part,
A secondary introduction port for sending the air introduced into the atmosphere introduction unit from the primary introduction port into the ink storage chamber;
An ink cartridge comprising a secondary valve for opening and closing the secondary inlet.   2. The ink cartridge according to claim 1, wherein the primary valve and the secondary valve are urged by an urging member toward a closed position for closing each of the primary and secondary inlets.   The ink cartridge according to claim 1, wherein the secondary valve is a magnet valve that can be opened and closed by an electromagnet.   In the air introduction part, a part of the peripheral wall is formed of a flexible member in the introduction path from the primary introduction port to the secondary introduction port, and air flowing from the primary introduction port and the secondary introduction port The ink cartridge according to claim 1, further comprising a buffer chamber for receiving the ink cartridge.   The secondary valve opens when the pressure in the ink storage chamber rises above the pressure in the atmosphere introduction portion, and opens the secondary introduction port against the urging force of the urging member due to the pressure difference. The ink cartridge according to claim 2, wherein the ink cartridge is movable to a position. An inkjet recording apparatus that includes an ejection type recording head and records an image using the recording head;
A main body including an ink storage chamber that is detachably set in the ink jet recording apparatus and stores ink to be supplied to the recording head, and an ink supply unit for supplying ink in the ink storage chamber to the recording head An ink jet recording system comprising an ink cartridge including an air introduction unit that introduces air into the ink storage chamber according to the pressure of the ink storage chamber;
The ink cartridge includes a primary valve that opens and closes a primary introduction port formed in the atmosphere introduction unit, a secondary introduction port for sending the atmosphere introduced from the primary introduction port to the ink storage chamber, and the secondary introduction A secondary valve for opening and closing the mouth,
The ink jet recording apparatus includes an ink jet recording system having two driving units that independently open and close the primary valve and the secondary valve.

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