JP2009126086A - Fluid discharge device and recording head - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fluid evacuation device capable of well discharging unnecessary foams and gas even when miniaturizing the same. <P>SOLUTION: The fluid discharge device having a fluid discharge channel for discharging fluid upward, a seal section arranged in the mid of the fluid discharge channel, a float member with a specific gravity smaller than a liquid blocking the fluid discharge channel by contacting with the seal section, and a float chamber where the float can move is characterized in that the uppermost end of the inlet through which the fluid discharged from the fluid discharge device enters the float chamber is located above the site where the cross section area in the face perpendicular to the gravitational direction of the float member located in the lowermost point of the inside of the float chamber is largest. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a fluid discharge device, and more particularly to a fluid discharge device in an ink supply device for supplying ink used in an ink jet recording apparatus from a main tank to a recording head. Alternatively, the present invention relates to a recording head provided with a fluid discharge device.

  Among recording methods such as printers, inkjet recording methods that form characters and images on recording media by ejecting ink from nozzles (nozzles) are low-noise, non-impact recording methods with high density and high-speed recording. In recent years, it has been widely adopted.

  A general ink jet recording apparatus includes an ink jet recording head, means for driving a carriage on which the ink jet recording head is mounted, means for transporting a recording medium, and control means for controlling these. A device that performs a recording operation while moving the carriage is called a serial scan type. On the other hand, one that performs a recording operation only by transporting a recording medium without moving the inkjet recording head is called a line type. In a line-type ink jet recording apparatus, an ink jet recording head has a large number of nozzles arranged over the entire width of the recording medium.

  The ink jet recording head has energy generating means for generating energy for discharging given to the ink in the nozzle in order to discharge ink droplets from the nozzle. As an energy generation means, one using an electromechanical transducer element such as a piezo element, one using an electrothermal transducer element such as a heating resistor, or converting electromagnetic waves such as radio waves or lasers into mechanical vibration or heat. There are those using electromagnetic wave mechanical transducer elements, electromagnetic wave heat transducer elements, and the like.

  Among them, the method of ejecting ink droplets using thermal energy enables high-resolution recording because the energy generating means can be arranged with high density. In particular, an ink jet recording head using an electrothermal transducer element as an energy generating means can be more easily downsized than one using an electromechanical transducer element. Furthermore, by making full use of the advantages of IC technology and microfabrication technology that have made remarkable progress and improved reliability in the recent semiconductor manufacturing field, high-density mounting is easy and manufacturing cost can be reduced. There is an advantage.

  Recently, inkjet recording apparatuses have been used for plotters that record photographic images on large sheets such as A1 and A0 plates.

  As a method of supplying ink to the ink jet recording head, there is a so-called head tank integrated method in which an ink tank for storing ink is integrated with the ink jet recording head. As a so-called head tank separation method in which the ink tank is separated from the ink jet recording head, there is a so-called tube supply method in which the ink tank and the ink jet recording head are connected by a tube. Further, as a head tank separation method, there is a so-called pit-in method in which the ink jet recording head is moved to the position of the ink tank as necessary to connect them, and ink is supplied from the ink tank to the ink jet recording head during that time.

  Increasing the capacity of the ink tank to reduce the replacement frequency of the ink tank increases the weight of the ink tank. This indicates that the weight applied to the carriage increases in the serial scan type ink jet recording apparatus. In consideration of this, a serial scan type ink jet recording apparatus that needs to use a large-capacity ink tank, such as outputting a large-sized recording image, often employs a tube supply method capable of continuous recording for a long time. .

  In printers and plotters that use a large amount of ink as described above, if an ink tank is mounted on the carriage, the ink tank is limited to a small one, and it is inconvenient to frequently replace the ink tank. In addition, running costs are expensive.

  Therefore, an ink supply system as shown in FIG. 11 is generally used in such an ink jet recording apparatus that consumes a large amount of ink.

  In FIG. 11, the recording head 201 is mounted on a carriage 202 that is movable with respect to the apparatus main body. On the other hand, a main tank 204 is fixed to the apparatus main body.

  When the ink is low, the main tank 204 is replaced. The recording head 201 and the main tank 204 are connected by an ink supply tube 200 formed of a tube, a joint, and the like. Since the carriage 202 reciprocates during printing, a flexible tube (for example, a silicon tube, a polyethylene tube, or the like) is used as at least a part of the ink supply tube 200 so as not to hinder the movement of the carriage 202. . The main tank 204 is provided with an atmosphere communication hole (not shown), and the inside of the main tank 204 communicates with the atmosphere. Therefore, when ink is ejected from the recording head 201, the ink is supplied from the main tank 204 through the ink supply tube 200.

  When this method is used, ink supply can be realized with a very simple configuration. However, since the flexible tube used for the ink supply tube 200 is made of rubber or resin, it has a slight gas permeability. Have. Since the inside of the tube has a negative pressure as in the recording head, air gradually enters the tube from the atmosphere through the tube wall to generate bubbles. When the bubbles flow into the recording head 201, normal ink droplets cannot be ejected, and printing failure occurs. Further, even if air can be prevented from gradually entering the tube through the tube wall from the atmosphere, the air dissolved in the ink may grow into bubbles in the tube and the sub tank.

  Therefore, even if bubbles are generated, an ink supply system that accumulates the bubbles in a sub tank provided on the recording head and discharges the air in the sub tank so that the air does not enter the recording head is disclosed in Patent Literature. 1 is proposed.

  The conventional sub-tank exhaust means will be described with reference to FIGS. 12 and 13 are sectional views of an ink jet recording head and a tank for storing ink to be supplied to the ink jet recording head.

  The sub tank 2 is divided into two spaces, a float part 102 and an air buffer part 103. A spherical float 9 is enclosed in the float portion 102. As the material of the float 9, a material having a specific gravity smaller than that of the ink and hardly reacting with the ink is selected. For example, polypropylene is used. Of course, a material having a specific gravity greater than that of the ink may be hollow and the specific gravity of the component itself may be smaller than that of the ink. The upper part of the partition plate 101 completely blocks the float part 102 and the air buffer part 103. The lower part of the partition plate 101 is provided with a slit 104 that is continuous in the vertical direction, and the float 9 does not move to the air buffer unit 103, but ink and air can freely pass therethrough. A conical portion 105 having a conical shape is provided on the upper portion of the float portion 102, and an exhaust port 108 and a connection portion 106 of the exhaust tube 10 are formed at a position corresponding to the apex of the conical portion 105. On the other hand, a connection portion 107 of the supply tube 5 is formed at the upper portion of the air buffer portion 103, and a pipe portion 109 extends downward from the connection portion 107 in the sub tank 2. For this reason, the ink in the supply tube 5 and the ink in the sub tank are always kept in contact with each other.

  FIG. 13 shows a state immediately after exhausting the sub tank. When printing and leaving (standby state and power-off state) are repeated from this state, bubbles generated in the supply tube 5 gradually enter the sub tank. At this time, since a valve (not shown) provided in the middle of the exhaust tube 10 is closed, the ink exits from the nozzle 6 by printing and head recovery operation, but the increased air is confined in the sub tank. As shown in FIG. 12, the ink surface is lowered.

  When the air in the sub-tank 2 is discharged, the head recovery unit 40 rises and covers the nozzle 6 of the recording head 1 and shields it from the outside air. Then, a pump (not shown) connected to the exhaust tube 10 operates to suck air in the sub tank 2 little by little, and the pressure in the sub tank 2 begins to gradually decrease. When the pressure drops to a certain extent, ink is supplied from a main tank (not shown) through the supply tube 5. Instead of the supplied ink, the air that was in the sub tank 2 exits through the exhaust tube 10. At this time, in the state shown in FIG. 12, the ink surface rises uniformly. When the ink surface reaches the uppermost part of the slit 104, the air in the float unit 102 and the air buffer unit 103 is completely blocked, and thereafter, only the air in the float unit is discharged. If air is discharged and the ink surface rises, naturally the float 9 also rises accordingly.

The float 9 initially rises without being fixed in the horizontal direction within the float portion 102, but after reaching the conical portion 105, it rises so as to approach the virtual vertex of the conical portion 105. Finally, as shown in FIG. 13, the operation stops at a position where the entire circumference contacts the conical portion 105 and closes the exhaust port 108 to complete the exhaust operation.
JP 2000-301737 A

  Incidentally, in recent years, further improvement in performance has been demanded for ink jet recording apparatuses.

  For example, it is required to reduce the nozzle pitch in order to output a higher-definition image, or to increase the number of inks used for expanding the color expression area. In order to further increase the speed, it is also required to increase the number of nozzles and increase the moving speed of the carriage.

  Increasing the number of inks used requires the number of recording heads and the corresponding ink supply system, which increases the size and weight of the apparatus.

  Increasing the size and weight of the recording head increases the load when the carriage moves, which is disadvantageous for high-speed recording.

  Therefore, the ink jet recording apparatus is required to be further reduced in size and weight while incorporating the above-described functions for improving performance, and the ink supply structure needs to be further downsized. is there.

  However, in the configuration as described above, there has been the following problem when the size is reduced.

  When bubbles flow into the float chamber, the float member is pushed up by the bubbles. Alternatively, when not only bubbles but also a small amount of liquid flows into the float chamber, the gap between the float member and the float chamber is sealed with bubbles or a small amount of liquid.

  In this state, when suction is performed from the discharge channel side by the suction means, a pressure difference is generated between the upstream side and the downstream side of the float member, so that the float member moves, contacts the seal member, and the exhaust channel is closed. . In such a case, there is a problem that the gas in the ink tank cannot be sufficiently discharged.

  In view of the problems as described above, it is an object of the present invention to provide a fluid exhaust device that can efficiently discharge unnecessary bubbles and gas even when downsized.

In order to achieve the above object, the fluid discharge device of the present invention comprises:
A fluid discharge channel for discharging the fluid upward;
A seal provided in the middle of the fluid discharge channel;
A float member having a specific gravity smaller than that of the liquid blocking the fluid discharge flow path by contacting the seal portion;
In the fluid discharge device having a float chamber in which the float is movable,
The upper end of the inlet through which the fluid discharged from the fluid discharge device flows into the float chamber has the largest cross-sectional area on the surface perpendicular to the direction of gravity of the float member located at the lowest point in the float chamber It is a fluid discharge device characterized by being above a part.

  As described above, according to the present invention, it is possible to provide a fluid exhaust device that can exhaust unnecessary bubbles and gas even when downsized.

  Embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic diagram for explaining an ink supply system of an ink jet recording apparatus using the fluid discharge apparatus according to the first embodiment of the present invention.

  In FIG. 1, the recording head 1 has a recording element chip 51 which is an ink discharge section in which a plurality of recording elements and a plurality of orifices 52 for discharging ink are arranged. Further, the recording head 1 includes a first ink chamber 50 connected in common to the plurality of orifices 52. Further, the recording head 1 has a sub tank 53 (second ink chamber) that receives and stores ink supplied from an external main tank 56 via a first filter, and supplies the first ink chamber 50 ink. is doing.

  A buffer tank 54 is provided between the inkjet recording head 1 and the main tank 56 for primary storage of ink. Above the buffer tank 54, a fluid discharge device 57 for discharging the gas taken in the buffer tank 54 and the supply tube 55 constituting the liquid flow path is provided.

  Ink is supplied from the main tank 56 to the recording head 1 by performing a suction operation by a cap 69 provided so as to seal the orifice 52 and a pump 61 as suction means connected to the cap. The

  The buffer tank 54 is provided with a fluid discharge device 57 so that the gas mixed in the supply tube 55 or the gas taken in when the main tank 56 is replaced does not enter the recording head, and is connected to the pump 61 by the exhaust tube 58. The

  Switching of the ink supply to the recording head 1 and the exhaust from the buffer tank 54 is performed by a switching valve 60 provided between the cap 59 and the pump 61.

  2 and 3 are diagrams for explaining the fluid discharge device 57 in FIG. 1 in more detail.

  In FIG. 2, the fluid discharge device 57 includes a fluid discharge channel 62 for discharging gas from the buffer tank 54, and a float chamber 64 provided in the middle of the fluid discharge channel 62. The float chamber 64 is connected to the exhaust tube 58 at the upper portion, and a seal portion 65 is formed at an exhaust port 58 a communicating with the exhaust tube 58.

  A float member 63 having a specific gravity smaller than that of the liquid supplied to the recording head 1 is movably accommodated in the float chamber. When the float member 63 comes into contact with the seal portion 65, the discharge port 58a communicating with the exhaust tube 58 is blocked. The

  As shown in FIG. 3, the fluid discharge channel 62 has a first channel 67 that guides the fluid to the float chamber 64. The fluid flowing through the first flow path 67 flows into the float chamber 64 from the entrance 67 a to the float chamber 64. The upper end 74 of the inlet 67a is at a position higher than the portion 75 having the largest cross-sectional area in the plane orthogonal to the direction of gravity of the float member 63 located at the lowest point of the float chamber 64. Therefore, the fluid flowing through the first flow path flows into the float chamber 64 from above the portion where the horizontal cross-sectional area of the float member 63 is the largest. In other words, the gap between the float member and the wall surface of the float chamber 64 is configured to flow into the float chamber from above the portion where the horizontal cross-sectional area is the smallest. In other words, the horizontal plane in which the difference between the cross-sectional area obtained by cutting the float member 63 positioned at the lowest point of the float chamber 64 along a horizontal plane and the cross-sectional area obtained when the float chamber 64 is cut along the same horizontal plane as the horizontal plane is minimized. The upper end of the inlet 67a is above the height of.

  The state in which the float member 63 is at the lowest point in the float chamber refers to a state in which the float member 63 is in contact with the bottom surface 64a of the float chamber 64 by gravity as shown in FIG.

  By doing so, even if the bubbles 66 flow into the float chamber 64, most of the bubbles 66 pass through the upper part of the float member 63. Therefore, the movement of the float member due to bubbles is eliminated, and the exhaust path 58 is not blocked by the float member 63 before the gas is discharged.

  By making the exhaust passage 58 have a negative pressure by the pump 61, the buffer tank 54 is filled with ink supplied from the main tank 56, and the ink level in the buffer tank 54 rises. Bubbles 66 that have accumulated in the upper part of the ink surface before the ink flow into the float chamber 64. The bubbles are discharged from the exhaust tube 58 without causing the float member 63 to rise.

  When the ink level further rises, ink flows into the float chamber 64. When the float member 63 comes into contact with the floating seal portion 65 by the ink flowing into the float chamber 64, the discharge port 58a is closed, and the discharge operation is completed.

  The seal portion may be formed integrally with the float chamber, or a separate member may be provided.

  Thereby, it is possible to reliably discharge the gas in the buffer tank 54 without discharging useless ink.

  FIG. 4 is a view for explaining a second embodiment of the fluid discharge device of the present invention.

  In the fluid discharge device 57 of FIG. 4, the fluid discharge channel 62 is branched into a first channel 67 and a second channel 68, and each is connected to the float chamber.

  The first flow path 67 allows the fluid from the fluid discharge flow path 62 to flow into the float chamber 64 from above the portion having the largest horizontal cross-sectional area of the float member 63 located at the lowest point of the float chamber 64.

  The second flow path 68 allows the fluid from the fluid discharge flow path 62 to flow into the float chamber 64 from below the portion having the largest horizontal cross-sectional area of the float member 63 located at the lowest point of the float chamber 64.

  FIG. 5 is a view for explaining a third embodiment of the fluid discharge device of the present invention.

  FIG. 5 shows that the flow resistance of the first flow path 67 in FIG. 4 is smaller than the flow resistance of the second flow path. Specifically, the “cross-sectional area / length” of the first flow path 67 is configured to be larger than the “cross-sectional area / length” of the second flow path 68.

  FIG. 6 is a view for explaining a fourth embodiment of the fluid discharge device of the present invention.

  FIG. 6 shows a flow path 69 in which the first flow path 67 and the second flow path 68 in FIG. 4 are connected together, and FIG. 6 (a) is a DD sectional view of FIG. 6 (b). It is.

  In FIG. 6, the fluid discharge channel 62 is configured to guide the fluid to the float chamber from the lower side with respect to the gravitational direction than the bottom surface 64 a of the float chamber 64.

  4 to 6, the upper end of the inlet 67 a to the float chamber 64 is higher than the portion where the cross-sectional area of the float member 63 is the largest. Therefore, the fluid from the fluid discharge channel 63 flows into the float chamber 64 from above the portion where the cross-sectional area of the float member 63 located at the lowest point of the float chamber 64 is the largest. Therefore, the float member 63 is not lifted by air bubbles, and the function of not discharging wasteful ink while discharging gas reliably can be maximized.

  FIG. 7 is a view for explaining a fifth embodiment of the fluid discharge apparatus of the present invention.

  FIG. 7 shows the flow channel 69 in FIG. 6 that flows from two places into the float chamber. Fig.7 (a) is EE sectional drawing of FIG.7 (b). If there is no problem in terms of space, it is possible to provide two or more flow paths.

  In FIG. 7, the fluid discharge channel 62 is configured to guide the fluid from the lower side with respect to the gravitational direction from the bottom surface 64 a of the float chamber 64 to the float chamber.

  FIGS. 8A to 8D are views for explaining the state of the fluid discharge device of the present invention when the fluid is discharged. In this description, the case of the fluid discharge device of the third embodiment shown in FIG. 5 is shown.

  FIG. 8A is a diagram showing an initial state, in which there is no liquid in the fluid discharge device, and the float member 63 is located at the lowest end of the float chamber 64.

  FIG. 8B shows a state in which suction in the arrow direction in the drawing is started by setting the exhaust passage 58 to a negative pressure by the pump 61. The ink level in the buffer tank 54 rises, and the gas or bubbles 66 in the buffer tank 54 are discharged through the first flow path 67 and the second flow path 68, but most of them are the first. It is discharged through one flow path 67. The bubbles are discharged from the exhaust tube 58 without causing the float member 63 to rise.

  When the suction is further continued, the liquid level rises as shown in FIG. 8C and the ink flows into the float chamber 64. As the liquid level rises, the float member 63 also rises.

  When the suction is further continued, the float member 63 comes into contact with the seal portion 65 as shown in FIG. 8D, shuts the exhaust passage 58, and ends the fluid discharge.

  In this way, by configuring the fluid to flow into the float chamber 64 from above the maximum horizontal cross section of the float member 63 located at the lowermost end of the float chamber 64, the phenomenon of the float member being pushed up by bubbles is eliminated. And it becomes possible to discharge | emit the gas and bubble in a tank efficiently.

  FIG. 9 is an explanatory view showing a sixth embodiment in which the fluid discharge device according to the present invention is applied to an ink jet recording head.

  In FIG. 9, 51 is a recording element chip in which a plurality of recording elements (not shown) and a plurality of orifices 52 for ejecting ink are arranged, and 70 is a first ink commonly connected to the plurality of orifices 52. It is a room.

  Above the first ink chamber 70, a second ink chamber 71 for storing ink supplied from the external main tank 56 via the supply tube 55 is disposed. The ink stored in the second ink chamber 71 is supplied to the first ink chamber 70 via the filter 72.

  An exhaust port 73 is provided in the second ink chamber 71, and the fluid discharge device 57 of the present invention is provided above the exhaust port 73.

  In the fluid discharge device 57, the fluid discharge channel 62 is branched into a first channel 67 and a second channel 68, and each is connected to the float chamber 64.

  The upper end of the inlet 67a to the float chamber 64 is at a position higher than the portion where the cross-sectional area of the float member 63 is the largest. The first flow path 67 allows the fluid from the fluid discharge flow path 62 to flow into the float chamber 64 from above the portion having the largest horizontal cross-sectional area of the float member 63 located at the lowest point of the float chamber 64.

  The second flow path 68 allows the fluid from the fluid discharge flow path 62 to flow into the float chamber 64 from below the portion having the largest horizontal cross-sectional area of the float member 63 located at the lowest point of the float chamber 64.

  Further, the exhaust tube 58 on the exhaust side of the fluid exhaust device 57 is connected to suction means (not shown) such as a pump. When the exhaust tube 58 is decompressed by the pump, the bubbles can be discharged without causing the float member 63 to be lifted by the bubbles, as in the above-described embodiment. When the bubbles are discharged and the liquid level rises, the float member 63 comes into contact with the seal portion 65, blocks the exhaust path 58, and ends the fluid discharge.

  Thus, by providing the fluid discharge device of the present invention in the ink jet recording head, the problem of ink ejection due to air bubbles can be more effectively prevented. That is, it is possible to remove bubbles while minimizing wasteful ink discharge, and a small and highly reliable ink jet recording apparatus can be provided.

  FIG. 10 is an explanatory view showing a seventh embodiment in which a fluid discharge device according to the present invention is provided in an ink jet recording head.

  10 is different from FIG. 9 in that a flow path that allows the fluid to be discharged from the first ink chamber 70 on the downstream side of the filter 72 is provided, and a fluid discharge device is provided in the flow path. is there. That is, a first fluid discharge device 571 is provided in the first ink chamber, and a second fluid discharge device 572 is provided in the second ink chamber. Each fluid discharge device includes a float chamber 64, a float member 63, a seal portion 65, a first flow path 67, and a second flow path 68, as in FIG. 9.

  The ink supply and gas discharge process will be described with reference to FIG.

  The ink supply port 77 is connected to an ink tank (not shown) by a tube or the like.

  During the gas discharging operation, first, the cap 59 is moved so as to be in close contact with the periphery of the orifice 52 to seal the orifice 52. Subsequently, the switching valve 60 brings the pump 61 and the fluid discharge channel 78 into communication.

  Subsequently, the pump 61 is started and the fluid discharge channel 78 is depressurized. The discharge of the fluid from the second ink chamber 71 is started first because of the flow path resistance. Ink is supplied from the ink supply tube 77 as the gas is discharged. The fluid in the second ink chamber 71 is discharged via the second fluid discharge device 572. In the second fluid discharge device 572, as in the embodiment of FIG. 9, bubbles are discharged first, and when the float chamber 64 is filled with ink, the flow path to the fluid discharge path 78 is closed by the float member 63 and the seal portion 65. Is done.

  Subsequently, gas discharge from the first liquid chamber 70 is performed. The gas discharge from the first liquid chamber 70 is performed in the same manner as described above, and unnecessary gas in the recording head is efficiently discharged. The end of the gas discharge process is ended by time setting or when a prescribed pressure is reached by providing a pressure detector (not shown) in the fluid discharge flow path 78.

  Thus, by providing the fluid discharge device of the present invention in both the first ink chamber 70 and the second ink chamber of the ink jet recording head, the problem of ink ejection due to air bubbles can be more effectively prevented. That is, it is possible to remove air bubbles satisfactorily, it is possible to minimize wasteful ink discharge, and it is possible to provide a small and more reliable ink jet recording apparatus.

  As the material of the float member 63, a material having a specific gravity smaller than that of the ink and hardly reacting with the ink is selected. For example, polypropylene or the like is used. Smaller than ink.

It is the schematic which shows the inkjet recording device supply system carrying the fluid discharge apparatus which is the 1st Embodiment of this invention. It is a figure for demonstrating the fluid discharge apparatus which is 1st Embodiment. It is a figure for demonstrating the fluid discharge apparatus which is 1st Embodiment. It is a figure for demonstrating the fluid discharge apparatus which is 2nd Embodiment. It is a figure for demonstrating the fluid discharge apparatus which is 3rd Embodiment. It is a figure for demonstrating the fluid discharge apparatus which is 4th Embodiment. It is a figure for demonstrating the structure which mounted the fluid discharge apparatus which is 5th Embodiment in the inkjet recording head. It is a figure for demonstrating a mode that the fluid is discharged | emitted in 3rd Embodiment. It is a figure for demonstrating the fluid discharge apparatus which is 6th Embodiment. It is a figure for demonstrating the fluid discharge state by the fluid discharge apparatus which is 7th Embodiment. It is a figure which shows schematic structure of the ink supply system of the conventional inkjet recording device. It is sectional drawing which shows the exhaust means of the conventional ink chamber. It is sectional drawing which shows the exhaust means of the conventional ink chamber.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Recording head 2 Sub tank 5 Supply tube 6 Nozzle 9 Float 10 Exhaust tube 51 Recording element chip 52 Orifice 53 Sub tank 54 Buffer tank 55 Supply tube 56 Main tank 57 Exhaust device 58 Exhaust tube 59 Cap 60 Switching valve 61 Pump 62 Fluid discharge device 63 Float member 64 Float chamber 65 Seal portion 66 Bubble 67 First flow path 68 Second flow path 69 Flow path 70 First ink chamber 71 Second ink chamber 72 Filter 73 Exhaust port 74 Upper end of first flow path 75 Maximum cross-sectional area of float member 76 Ink 77 Ink supply port 78 Fluid discharge flow path 101 Partition plate 102 Float part 103 Air buffer part 104 Slit 105 Conical part 106 Connection part 107 Connection part 108 Exhaust port 109 Pipe part 00 ink supply tube 201 recording head 202 the carriage 203 conveying rollers 204 main tank

Claims (8)

A fluid discharge channel for discharging the fluid upward;
A seal provided in the middle of the fluid discharge channel;
A float member having a specific gravity smaller than that of the liquid blocking the fluid discharge flow path by contacting the seal portion;
In the fluid discharge device having a float chamber in which the float is movable,
The upper end of the inlet through which the fluid discharged from the fluid discharge device flows into the float chamber has the largest cross-sectional area on the plane perpendicular to the direction of gravity of the float member located at the lowest point in the float chamber A fluid discharging apparatus, wherein the fluid discharging apparatus is located above a part. A first flow path for guiding fluid discharged from the fluid discharge device to the inlet;
2. The second flow path according to claim 1, further comprising a second flow path for allowing the fluid discharged from the fluid discharge device to flow into the float chamber from below the portion having the largest cross-sectional area of the float member positioned at the lowest point of the float chamber. Fluid discharge device.   The fluid discharge device according to claim 2, wherein the flow resistance of the first flow path is smaller than the flow resistance of the second flow path.   The fluid discharge device according to claim 2, wherein the inlet also serves as an inlet of the second flow path.   5. The fluid discharge device according to claim 1, wherein the fluid is discharged from a liquid flow path for supplying the liquid to a discharge port that discharges the liquid and performs recording on the recording medium. An ink discharge portion for discharging ink;
A first ink chamber communicating with the ink discharge portion;
A second ink chamber for storing ink supplied from an external ink tank and supplying the stored ink to the first ink chamber via a filter;
An exhaust port provided in the second ink chamber,
A recording head comprising the fluid discharge device according to claim 1, wherein the fluid discharge channel of the fluid discharge device is connected to the exhaust port. An ink discharge portion for discharging ink;
A first ink chamber communicating with the ink discharge portion;
A second ink chamber for storing ink supplied from an external ink tank and supplying the stored ink to the first ink chamber via a filter;
An exhaust port provided in the first ink chamber,
A recording head comprising the fluid discharge device according to claim 1, wherein the fluid discharge channel of the fluid discharge device is connected to the exhaust port. A fluid discharge channel for discharging the fluid upward;
A seal provided in the middle of the fluid discharge channel;
A float member having a specific gravity smaller than that of the liquid blocking the fluid discharge flow path by contacting the seal portion;
In the fluid discharge device having a float chamber in which the float is movable,
The upper end of the inlet through which the fluid discharged from the fluid discharge device flows into the float chamber has a cross-sectional area obtained by cutting the float positioned at the lowest point of the float chamber along a horizontal plane, and the float chamber is cut along the same horizontal plane as the horizontal plane. The fluid discharge device according to claim 1, wherein a difference from the cross-sectional area is higher than a height of the horizontal plane that is minimized.

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