JP3992030B2 - Liquid supply device - Google Patents

Description

The present invention relates to an ink supply KyuSo location for supplying ink to a recording head for ejecting ink droplets in response to print signals in a proper negative pressure state.

  An ink jet recording apparatus usually includes an ink jet recording head that ejects ink droplets in response to a print signal on a carriage that reciprocates in the paper width direction of the recording paper, and supplies ink from an external ink tank to the recording head. It is configured. An ink storage container such as an ink tank is configured to be detachably mounted on a carriage in consideration of handling convenience in a small recording apparatus.

Such an ink storage container is usually configured to contain a porous material in order to prevent leakage of ink from the recording head, and to impregnate the porous material with ink and hold the ink by capillary force. Has been.
On the other hand, improvement in printing quality and printing speed is required, and along with this, the number of nozzle openings in the recording head increases, and ink consumption per unit time tends to increase.

In order to cope with such a tendency, it is desirable to increase the amount of ink stored in the ink storage container, and the volume of the porous material increases. However, to hold the ink with the capillary force of the porous material, there is a limit to the height, that is, the water head, so the bottom area must be increased to increase the volume, and the carriage size increases. As a result, there is a problem that the recording apparatus is enlarged.
In order to solve such a problem, as seen in Patent Document 1, a membrane valve seat is formed by providing a through hole in the center of a membrane body that can be deformed by the pressure of ink, while the valve is located at a position opposite to this. An ink cartridge having a body has been proposed.
In order to solve such problems, Patent Document 2 discloses that a valve body is formed by injection molding of a polymer material having elasticity, a through hole is formed in the center, and the back surface is pressed against the sealing body by a spring. There has been proposed an ink cartridge in which the valve body is moved by a negative pressure acting on the back surface of the valve body to cause ink to flow out to the ink supply port via a through hole.
In recent years, an ink cartridge having a high ink supply capability capable of supplying a large amount of ink to a recording head has been required to meet the demand for high-speed printing and the like. The greatest factor that affects the ink supply capacity to the recording head is the flow path resistance in the cartridge.
In the ink cartridge disclosed in Japanese Patent Application Laid-Open No. 2004-228561, a through hole that causes ink circulation in the film body becomes a cause of fluid resistance, and a large fluid resistance is also generated in the gap between the through hole and the valve body that cooperates.
As a measure to reduce the fluid resistance due to the through-holes of the membrane body, it is conceivable to enlarge the diameter of the through-holes. However, there is a problem that the load is reduced, the sealing pressure is lowered, and the sealing performance is deteriorated.
For this reason, a convex portion is formed in a region facing the sealing body of the valve body to improve the sealing performance, and a through hole is formed in the convex portion, but the convex portion is formed by the biasing force of the spring. The valve closed state is maintained in a state of being elastically deformed and crushed.
Therefore, even if the negative pressure is applied to the valve body and the convex portion that is elastically deformed returns to the original state even if the negative pressure acts to retreat from the sealing body, the flow resistance at the time of valve opening is reduced. When the amount of ink consumption increases per unit time, such as when printing an image or the like, sufficient ink may not be supplied.
Further, in order to stabilize the closed state of the valve body, the convex part is sufficiently crushed by the urging force of the spring, and in order to closely contact the sealing body of the valve body, the convex part of the valve body is made of an elastic material made of an elastomer. Has been. In addition, since the convex part of the valve body is thicker than the film surface that receives the differential pressure, resin turbulence occurs during injection molding, and welds are likely to occur during molding. It was difficult to form a large protrusion.
In addition, since the deviation of the concentricity between the convex part of the valve body and the sealing body arises from component accuracy and assembly variation, it is necessary to configure the contact surface of the sealing body larger than the diameter of the convex part of the valve body. there were.
Under these circumstances, there is a problem that the sealing body exists in a wide area around the convex portion of the valve body, and the flow path resistance increases.
In addition, since it is necessary to form convex portions and through-holes in the valve body, there is a problem that wrinkles and grooves due to welds are likely to occur in the sealing region, resulting in a low manufacturing yield.
Furthermore, with regard to the shape of the through hole of the valve body for reducing the flow resistance, for example, when a tapered through hole is formed in the film body, the thickness below the convex part becomes thin, and the convex part is deformed into the through hole. There is also a problem that the shape of the through hole is restricted.
[Patent Document 1] Japanese Patent Application Laid-Open No. 8-174860 International Publication No. 00/103877 Pamphlet US Pat. No. 5,653,251

The present invention has been made in view of such a problem, and an object of the present invention is to reduce the flow resistance of the through hole in the negative pressure generating mechanism and cope with the consumption of a large amount of ink in the recording head. to provide a liquid test KyuSo location.

  In order to achieve such a problem, in the present invention, an elastic member that can be moved by a differential pressure between one surface and the other surface, and an ink storage portion that stores ink on one surface of the elastic member A communicating portion that communicates with the ink discharge port and an opening portion of the communication passage that communicates with the ink discharge port, and a space that communicates with the ink discharge port is formed on the other surface of the elastic member. ing.

In order to achieve such a problem, in the present invention, a connection member, an upstream region connected to an external ink container via the connection member, an ink discharge port communicating with the upstream region, and ink consumption A negative pressure generating mechanism that opens along with the negative pressure generating mechanism, the negative pressure generating mechanism being disposed between a flow path connecting the upstream region and the ink discharge port, and The generating mechanism is provided on the first surface side of the elastic member, the elastic member having a first surface and a second surface, and not having a hole penetrating the first and second surfaces. , The first communication path for communicating the upstream region and the first space on the first surface side of the elastic member, the ink discharge port, and the first surface side of the elastic member on the first surface side. A flow path communicating with an opening provided so that the elastic member is in contact with and away from, and the elastic portion And a second space that communicates with the ink discharge port through a second communication path and communicates only with the second communication path, and is provided with the elastic member. When the opening is opened under the action of the reduced pressure on the ink discharge port side , ink is supplied from the upstream region to the ink discharge port through the first communication path and the opening, and the elastic member The first surface of the elastic member is influenced by the pressure change on the downstream side, that is, on the ink discharge port side as the ink is consumed, and the elastic member is surely opened.

Therefore, details of the present invention will be described below based on the illustrated embodiment.
FIGS. 1 and 2 (a) are assembled perspective views showing an embodiment of the ink cartridge of the present invention with front and back structures, respectively, and FIG. 3 is a cross-sectional view showing both side surfaces. The main body is composed of a frame body 2 having an opening 1 and lid bodies 3 and 4 for sealing the opening 1. An ink supply port 5 is formed on the distal end side in the insertion direction, in this embodiment, on the bottom surface. The ink supply port in the present invention means a connection member that removably connects the recording head provided on the carriage and the ink cartridge, for example, a hollow needle or a member or an opening through which a pipe can be inserted or connected. .

  In the vicinity of the frame body 2 facing the ink supply port 5, an ink supply flow path forming member 6 constituting a negative pressure generating means (negative pressure generating mechanism) 30 is disposed on one opening surface side of the frame body 2 with the opening 7. Are integrally formed.

The ink supply flow path forming member 6 is roughly divided into a valve body accommodating portion 8 that accommodates a substantially circular valve body (also referred to as an elastic member) 20 and a flow path portion 9 that communicates the ink supply port 5. A convex portion 11 having a first through hole 10 that forms an ink outlet is formed in the center of the accommodating portion 8, and a second through hole 12 that forms an ink inlet is formed at a position shifted from the convex portion 11. ing. Further, the flow path portion 9 is formed with a third through-hole 13 that forms an ink inlet that communicates with the front surface region of the valve body 20.
As shown in FIG. 4 (a), the first through-hole 10 expands to the substantially cylindrical straight portion S on the elastic member side and to the downstream side in the ink supply direction, that is, on the ink outlet side. The funnel-shaped portion R is continuous with the straight portion S. As a result, a reliable sealing performance can be ensured by the straight portion S, and the entire flow path resistance of the first through hole 10 can be lowered by the funnel-shaped portion R.

  On the other hand, a concave portion 15 that connects the first through hole 10 of the convex portion 11 and the third through hole 13 of the flow passage portion 9 is formed on the surface 14 of the wall surface 6 a that partitions the ink supply flow path forming member 6. The recess 15 is sealed with a film 16 to form a communication path (hereinafter referred to as 15 ').

As shown in FIG. 4, the ink supply flow path forming member 6 configured as described above is provided with an elastically deformable valve body 20 having a thick portion 20a around the convex portion 11 and a flat surface on the convex portion 11 side. It is loaded via the adjustment frame 21, and a differential pressure adjusting spring 22 is positioned and brought into contact with the convex portion 20 b formed at the center on the back surface (back surface) of the adjustment frame 21, and the outside is flowed by the pressing member 23. The portion 9 and the back surface of the valve body 20 are communicated with each other and sealed in a liquid-tight manner so as to be separated from the ink containing area.
For this reason, recesses 9 a and 23 a are formed in a region facing the flow path portion 9 of the ink supply flow path forming member 6, or one or both of the pressing members 23.

The valve body 20 is preferably formed of an elastic polymer material such as an elastomer that can be injection-molded, and is provided with a spring receiving convex portion 20b in a region facing the convex portion 11, that is, in the central portion. .
In addition, the film 24 is bonded to the partition wall 6b constituting the ink supply flow path forming member 6 so as to seal the valve body housing portion 8 and the flow path portion 9 so as to cover the surface of the pressing member 23, and is surely secured. The sealing and the ink containing area are divided.

  In the above-described embodiment, the second through hole 12 is formed in the same size as the first through hole 10, but the valve body 20 is urged as shown in FIG. Even if the remaining portion is formed so as not to be deformed by the pressing force of the spring 22 and the recess 15 serving as the communication path can be formed, and the other portion is formed as the window 12 ', the same effect can be obtained.

  In this embodiment, when the ink cartridge is mounted on the recording apparatus and the pressure on the ink supply port 5 side, that is, the most downstream area from which the ink is discharged from the ink cartridge due to the consumption of ink by the recording head or the like, The closed space opened only by the flow path formed by the recessed part 23a on the back surface of the flow path part 9 and the flow path part 15 'formed by the recessed part 15 and the film 16 and the valve body 20 communicating therewith. The pressure of 27 (hereinafter also referred to as a pressure action chamber) decreases, and a negative pressure acts on the surface pressed by the spring 22. However, when the negative pressure of the ink supply port 5 does not reach a predetermined value, the valve body 20 maintains the state where the first through hole 10 is sealed by the biasing force of the spring 22. Although the negative pressure acts on the first through hole 10 via the communication passage 15 ′, the front side of the valve body 20 acts on the front side of the valve body because the area of the through hole 10 is extremely small. The force to do is negligible compared to the back.

FIG. 4C is a cross-sectional view passing through the flow path portion 9 of the negative pressure generating means (negative pressure generating mechanism) 30.
When the negative pressure drops below the pressure set by the rigidity of the valve body 20 and the spring 22, the negative pressure of the ink supply port 5 acts on the pressure action chamber 27 of the valve body 20 communicated by the recess 23a or 9a. (Fig. 4 (c)). As a result, the valve body 20 moves away from the convex portion 11 against the urging force of the spring 22 (FIG. 4 (b)), and the ink in the ink containing region 17 passes through the second through hole 12 (FIG. 5 (b) arrow A). Then, it flows into the communication path 15 ′ via the first through hole 10 of the convex portion 11. The ink that has flowed into the communication path 15 ′ flows into the ink supply port 5 from the third through hole 13 through the flow path portion 9 (FIG. 5 (A) arrow B) (FIG. 5 (B) arrow C).

In this way, when a predetermined amount of ink flows into the ink supply port 5 and the pressure on the back surface of the valve body 20 rises, the valve body 20 is elastically pressed against the convex portion 11 by the urging force of the spring 22 and seals the through hole 10. Stop (FIG. 4 (a)).
Thereafter, such an operation is repeated to supply ink to the recording head while maintaining the pressure on the ink supply port side at a predetermined negative pressure.

  By the way, the sealing body of the valve body of the present invention is formed into a flat surface as shown in FIG. 6 (a), so that the valve body is in contact with the valve seat as in the conventional valve body 40 shown in FIG. Therefore, there is no weld that is likely to occur during injection molding, that is, a groove (a crack in FIG. 7), and the manufacturing yield can be improved.

Moreover, since the area | region which contact | abuts to the convex part 11 of the valve body 20 can be formed as wide as possible plane, it closely_contact | adheres to the convex part 11 used as a valve seat reliably, and obtains high sealing force. Can do.
On the other hand, the conventional valve body 40 is elastically deformed so that the convex portion 42 is pressed against the sealing body 44 by the elastic force of the spring 43 as shown in FIGS. 8 (a) and 8 (c). It will be in the state.

On the other hand, since the negative pressure acting when the valve is opened is constant, the elastically deformed region 42a returns to the original state even if it is separated from the sealing body 44, and the flow path gap L ′ is extremely small. There is a disadvantage that the resistance is large.
Further, since the through hole 41 is formed in the valve body 40 made of an elastically deformable material, the area of the sealing body 40 is increased in order to cope with the positional deviation of the through hole 41 due to the deflection of the valve body 40 or the like. There is a problem that it is necessary to form, and the narrow gap region in the vicinity of the through hole 41 is wide, leading to an increase in flow path resistance.

  On the other hand, in the present invention, since the sealing side of the valve body 20 is formed as a flat surface, there is no restoration even when the valve body 20 is restored by the action of negative pressure, and the gap L is maintained large. At the same time, since the first through hole 10 that forms the ink flow path when the valve is opened can be formed in the valve body housing portion having a rigidity higher than that of the valve body, the convex portion 11 can be made as small as possible and the valve body. 20 can be configured to ensure a sufficient flow path between the end surface of the through hole 10 and the flow path resistance in the vicinity of the through hole 10 can be reduced.

  In the above-described embodiment, the surface abutting on the valve seat is configured to be a flat surface. However, as shown in FIG. The same effect is exhibited. In this case, it can also be formed as a taper entering the through hole 10 of the convex portion 11.

  Moreover, in the above-mentioned Example, although the valve body and the frame body were comprised as a different body, the material suitable for each can also be comprised as a monolith by a two-color molding technique.

  Further, in the above-described embodiment, the wall that partitions the region for accommodating the negative pressure generating mechanism is integrally formed with the member that partitions the ink storing region. However, as shown in FIG. Even if the member that divides the region for storing the ink is configured as the separate member 31 and is inserted into the opening 5a on the upstream side of the ink supply port 5, the same effect can be obtained.

Next, another embodiment of the present invention will be described.
10 to 13 show the front and back structures of the ink cartridge with the opening sealing member removed, and FIGS. 14 to 16 show the cross-sectional structure of the negative pressure generating mechanism. Inside the container main body 50 constituting the storage area, the container body 50 is divided vertically by a wall 52 extending in a substantially horizontal direction, more specifically, the ink supply port 51 side slightly below. The ink supply port 51 accommodates a valve body (a member equivalent to the above-described elastic member) 54, a fixing member 55, and a spring 53. When the ink cartridge is not attached to the recording apparatus main body, the valve is The body 54 elastically contacts the fixing member 55 with a spring 53 to seal the ink supply port 51.

  A first ink containing area 56 is formed in the lower area of the wall 52, and an air communication path 58 is formed in the upper area with a certain gap from the wall 57 of the container body 50 so that the wall 52 is the bottom surface. In this way, it is partitioned by a frame portion 59. The inner region of the frame 59 is further divided by a vertical wall 60 having a communication port 60a formed at the bottom, and one region (the right region in the figure) serves as the second ink containing region 61 and the other. This region is formed as a third ink containing region 62.

  A suction channel 63 that connects the second ink storage region 61 and the bottom surface 50 a of the container main body 50 is formed in a region facing the first ink storage region 56. The suction channel 63 is formed by forming a recess 64 (FIG. 11) on the surface of the container body 50 and sealing the recess 64 with an airtight film 104 described later.

In the third ink containing region 62, an annular frame wall 65 and a flat surface 66 that divides the front and back surfaces are formed so as to be flush with the frame portion 59, thereby forming an ink supply flow path forming member 67. A vertical wall 68 is formed between the lower portion of the frame wall 65 and the wall 52, and a fourth ink containing region 69 is formed. A communication recess 68 a is formed in the lower portion of the wall 68.
In the fourth ink containing region 69, an ink flow path 71 is formed by providing a partition wall 70 between the frame portion 59. The upper part of the ink flow path 71 is communicated with the surface side of the container main body 50 through a through hole 72 serving as a filter chamber as necessary.

  The through hole 72 is separated by a wall 73 formed so as to be continuous with the wall 70, communicates with the upper end of the ink flow path 71 through the recess 73 a, and communicates with the water droplet-shaped recess 74 on the surface side of the container body 50. It finally communicates with the inside of the frame wall 65 through the opening 73b.

  The lower part of the ink supply flow path forming member 67 and the ink supply port 51 are connected to each other by a flow path composed of a recess 86 formed on the surface of the container body 50 and an airtight film covering the recess 86. In the ink supply flow path forming member 67, a valve body accommodating portion 81 is formed on the surface side of the container body 50 by a flat surface 66 opposite to the ink accommodating region and an annular wall 80 as shown in FIG. 13. A convex portion 83 having a through hole 82 is formed at substantially the center of the flat surface 66, and a communication passage 85 communicating with the front surface of the valve body 84 is formed at a position away from the convex portion 83. In the same way as shown in FIG. 4 (a), the through hole 82 expands to the substantially cylindrical straight portion S on the elastic member side, and to the downstream side on the downstream side in the ink supply direction. It is configured as a funnel-shaped portion R that expands and continues to the straight portion S. As a result, the straight portion S can ensure a reliable sealing property, and the funnel-shaped portion R can reduce the overall flow resistance of the through hole 82.

  Further, a notch 87 connected to a recess 86 extending in the direction of the ink supply port 51 is formed near the lower end of the wall 80. The notch 87 is set to a depth that opens only on the back side of the valve body 84 when the valve body 84 is loaded. On the other hand, a wall 88 that is separated from the periphery so as to avoid the communication passage 85 and extends in the upper end direction of the concave portion 86 is formed on the back surface facing the through hole 82, that is, the upper ink containing region side. 89 is connected to the upper end region of the recess 86.

On the surface of the container main body 50, a narrow groove 90 meandering so as to make the flow resistance as high as possible, a wide groove 91 around it, and a rectangular area in a region facing the second ink containing region 61 are rectangular. A concave portion 92 having a shape is formed. In the rectangular recess 92, a frame portion 93 is formed at a position further lowered, and ribs 94 are discretely formed inside thereof.
An air vent chamber is formed on the frame portion 93 by stretching a breathable film 95 having ink repellency and breathability.

  A through-hole 96 is formed in the bottom surface of the recess 92 and communicates with an elongated region 98 defined by a wall 97 formed inside the second ink containing region 61. Further, one end 90 a of the narrow groove 90 communicates with a region of the recess 92 on the surface side of the air permeable film 95. The other end of the region 98 is opened through the through-hole 99 formed here, the groove 108 formed in the surface of the container body 50, and the through-hole 99a while being attached to the recording apparatus. Is communicated with the valve accommodating region 101 that accommodates.

The valve body accommodating portion 81 of the container body 50 configured as described above is loaded with the valve body 84 and the spring 102 shown in FIG. 11 as in the above-described embodiment, and the holding member 103 is loaded. A film 104 covering the surface is attached. The presser member 103 is formed with a groove 105 communicating with the notch 87 and channels 106 and 107 communicating with the back surface of the valve body 84.
Accordingly, the recesses 74, 86, 105 cooperate with the film 104 to form an ink flow path, and the narrow grooves 90, 91, the recesses 92, 108 cooperate with the film to form a capillary or air communication channel. Configure.

Further, the opening side of the container body 50 is sealed with the film 110 at the opening of the upper ink containing regions 61, 67, 69 and the ink supply flow path forming member 67 surrounded by the frame 59 and the wall 52, A lower ink storage area 56 and an atmosphere communication path 58 are defined. Then, the container body 50 is sealed with the lid 111, whereby the lower ink containing area 56 is formed.
In the figure, reference numeral 120 denotes an identification piece for preventing the ink cartridge from being attached to the word, and reference numeral 121 denotes storage means for storing ink information and the like and attached to the recess 122 of the container body.

  When the thus configured ink cartridge is attached to the ink supply needle that communicates with the recording head, the valve element 54 is retracted by the ink supply needle against the spring 53 and the ink supply port 51 is opened. In this state, when the ink is consumed by the recording head due to a recording operation or the like and the pressure of the ink supply port 51 decreases, the back surface of the valve body 84 passes through the flow path formed by the recess 86 and the film 104 and the notch 87. That is, the pressure acts on the surface which is pressed by the spring 102. In a state in which the pressure of the ink supply port 51 has not dropped to a specified value, the valve body 84 maintains the state of being pressed by the urging force of the spring 102 to close the through hole 82. No ink flows from the ink containing area to the ink supply port 51.

  A connecting member for detachably connecting the ink supply port 51, that is, the recording head provided in the carriage and the ink cartridge as the ink consumption of the recording head proceeds, for example, a hollow needle or a member into which a pipe can be inserted or connected When the pressure of the flow path in the opening portion falls below the specified value, the pressure acting on the back surface of the valve body 84 via the flow path overcomes the spring 102, and the valve body 84 moves away from the convex portion 83. As a result, the ink flows into the region between the valve body 84 and the flat surface 66 from the communication passage 85, and the flow path formed by the wall 88 and the film 110 from the through hole 82, the through hole 89, the recess 86 and the film 104. The ink flows from the ink supply port 51 to the recording head via the formed flow path.

  When a predetermined amount of ink flows into the back surface of the valve body 84 and the pressure on the back surface of the valve body 84 rises, the valve body 84 is pressed against the convex portion 83 by the urging force of the spring 102 to close the through hole 82, Block. Accordingly, it is possible to supply ink to the recording head while maintaining the pressure on the ink supply port 51 side in a negative pressure state that can prevent leakage of ink from the recording head.

  In the process of consuming ink, the ink in the fourth ink containing region 69 flows from the flow path 71 and the through hole 72 to the front surface of the valve body 84 of the ink supply flow path forming member 67. On the other hand, since only the first ink storage area 56 is open to the atmosphere, when the ink in the fourth ink storage area 69 is consumed, the third ink storage area 62 communicated with the recesses 60a and 68a. When the third ink storage area is consumed, the ink in the second ink storage area 59 flows into the third ink storage area 62. When the ink in the second ink storage area 61 is consumed, the ink in the first ink storage area 56 flows through the suction channel 63. As a result, the ink in the first ink storage area 56 is consumed first, then the ink in the second ink storage area 61 is exhausted earlier in the upstream ink storage area.

FIG. 17 shows an embodiment in which the ink capacity of the above-described ink cartridge is increased, and the container body 50 ′ of this embodiment is the same as that of the above-described embodiment except that the width W is large. The container body 52 has the same structure.
Accordingly, the height of the partition wall 65 of the ink supply flow path forming member 67 and the frame body 59 ′ are different from each other, so that the opening of the partition wall 65 of the ink supply flow path forming member 67 is sealed with the third film 130. It is configured.

  10 to 16, the surface of the convex portion 83 of the ink supply flow path forming member 67 is configured to have a diameter several times larger than the diameter of the through hole 82. As shown in FIGS. 18 and 19, when the through-hole 82 ′ and the convex portion 83 ′ are formed in a conical section, the diameter of the through-hole 82 ′ is enlarged to lower the flow resistance, and the valve body 84 is penetrated. A wide channel space with the wall 83a ′ in the vicinity of the hole 82 ′ can be secured, and the channel resistance can be lowered.

  Next, the operation of the above-described negative pressure generating mechanism of the ink cartridge shown in FIGS. 10 to 16 will be further described with reference to FIGS. 20A and 20B, which are schematic diagrams with simplified structures. FIGS. 20A and 20B are schematic diagrams showing the above-described negative pressure generating mechanism in a simplified state and a valve-closed state and a valve-opened state, respectively, in order to correspond to the configuration of the negative pressure generating mechanism. Description will be made with the same reference numerals as those in the embodiment shown in FIGS.

  In the closed state of FIG. 20 (a), the valve body 84 closes the through hole 82 by the biasing force of the spring 102, so that the ink in the ink storage chamber 62 is prevented from flowing out to the ink supply port. When ink is consumed by the recording head in this state, the pressure on the ink supply port side decreases, and the pressure acts on the valve body 84 via the communication path 87 and the flow path 88.

By the way, the back surface of the valve body 84 with which the communication path 87 communicates forms a gap with the valve body 84 and forms a closed space opened to the outside only through the communication path 87. That is, it functions as a pressure working chamber for transmitting the pressure change of the ink supply port to the back surface of the valve body 84.
As a result, the valve body 84 is opened on the back surface and receives pressure on the ink supply port side over a wide area, while the other surface of the valve body 84 is reduced in pressure on the ink supply port side only through the opening 82. Receive. For this reason, force acts on the valve body 84 in the direction in which the spring 102 is compressed due to the difference in pressure receiving area between the front and back surfaces. When the pressure on the ink supply port side is lower than the pressure set by the spring 102, the valve body 84 is separated from the convex portion 83 as shown in FIG. Then, the ink in the ink storage chamber 62 flows into the recording head through the flow path 88.

At this time, since the ink flows only through the surface side of the valve body 84, even if the air bubbles stagnated in the ink storage chamber 62 are drawn, the ink flows on the recording head as it is. That is, since the back surface of the valve body 84 is a closed space (hereinafter, also referred to as a pressure action chamber) 109 as described above, a fast ink flow does not occur in the communication path 87, so that the bubble B is generated. It does not flow into the communication path 87 and hardly enters the back side of the valve body 84.
As a result, the pressure change on the ink supply port side surely acts on the back surface of the valve body 84 via the ink, so that the supply of ink does not stop. Even if air bubbles flow into the recording head, the air bubbles can be easily eliminated by applying a negative pressure to the recording head to forcibly discharge the ink.

On the other hand, as shown in FIG. 7, in the conventional ink cartridge in which the through hole 41 serving as the ink flow path is formed in the valve body 40, the pressure of the back surface of the valve body 40, that is, the ink supply port is set. Bubbles may flow into the receiving area, and the bubbles may reduce the driving force of the valve body.
That is, FIGS. 21A and 21B are schematic diagrams showing the negative pressure generating mechanism of the conventional ink cartridge, respectively, in a valve-closed state and a valve-opened state. When the pressure of the ink supply port 201 decreases and the pressure of the region 203 on the back surface of the valve body 40 decreases when the valve body 40 blocks the supply port 201 (FIG. 21A), the valve body 40 As shown in FIG. 21 (b), the spring 204 moves backward against the urging force of the spring 204, the through hole 41 serving as the ink flow path of the valve body 40 is separated from the convex portion 206, and the ink in the ink containing area 200 passes through the through hole 41. And flows into the ink supply port 201 via the region 203 on the back surface of the valve body 40. Note that reference numeral 208 in the drawing denotes a through hole that allows the ink containing region 200 and the valve body 40 to communicate with each other.

  At this time, if bubbles B are present in the ink flowing from the through holes 40, the bubbles B stagnate in the region 203 on the back surface of the valve body 202. As described above, when the bubble B enters the region 203 on the back surface of the valve body 40, that is, the region receiving the pressure of the ink supply port 201, the bubble B easily expands when the pressure in the region 203 decreases. Since the pressure drop is buffered, it is impossible to move the valve body 40, which causes a problem that ink cannot be supplied to the recording head.

  In addition, the through hole 41 of the valve body 40 is preferably formed in the convex portion 42 in order to seal the through hole 41 of the valve body 40 with the convex portion 206, but it corresponds to a positional shift due to deformation of the valve body 40. Therefore, it is necessary to increase the size S of the convex portion 206 that seals the through-hole 41 of the valve body 40 as much as possible, the area around the convex portion 206 is enlarged, and the convex portion 206 and the valve body 40 There is a problem that the area of the narrow gap increases and the resistance of the ink flow path also increases.

  On the other hand, in the present invention, in order to seal the opening 82 formed in the convex portion 83, the surface of the valve body 84 may be in close contact with the opening 82. The size of the convex portion 83 can be reduced as much as possible, and the area in the vicinity thereof, that is, the narrow gap region formed by the valve body 84 and the convex portion 83 can be reduced. Road resistance can be lowered.

  In the above-described embodiment, the back surface of the valve body 84 is configured as the closed space 109 opened to the outside only through the communication passage 87. However, as shown in FIGS. 22 (a) and 22 (b), the opening 82 is provided. The valve body 84 is connected to one end of the closed space 109 on the back surface of the valve body 84 and the flow path 88 connecting the ink supply port to the ink supply port, and the flow channel communicating with the ink supply port is formed in the pressure acting chamber. The area on the back surface of the ink can act as an ink flow path.

  Then, as in the embodiment shown in FIG. 22 (b), an ink discharge channel 86 ′ perpendicular to the surface of the valve body 84 is formed in the pressure acting chamber 109 on the back surface of the valve body 84, whereby the valve body 84 is formed. Can be used in a horizontal posture.

  In addition, a valve body made of an elastically deformable membrane, a convex portion that can be contacted by the valve body, and a flow path that can be closed by the valve body are formed in the convex portion, and is formed on one surface of the valve body. A valve structure that controls supply or stop of supply of a liquid by separating a valve body from a flow path by applying a negative pressure on the demand side is disclosed in Patent Document 3, but in a valve open state, the liquid of the valve body The pressure receiving area (receiving pressure area) becomes extremely small, and the difference between the front and back areas increases, so the valve cannot be maintained open even if the pressure changes as the ink is consumed by the printhead. Since the pressure receiving area becomes extremely large at the time of the valve state, there is a problem that the operation of opening the valve is repeated and pulsation occurs when ink is supplied.

  For example, when the embodiment shown in FIG. 4 is taken as an example, a spring 22 for adjusting the differential pressure is arranged on the back surface of the valve body 20 and brought into elastic contact with the convex portion 11, but as shown in FIG. If the valve body 20 is made of an elastic material such as rubber by projecting the convex portion 11 relatively to the valve body 20 side relative to the plane P formed by the valve body 20 itself, the elasticity of the valve body 20 The urging member such as the spring 22 can be omitted by making an elastic contact with the convex portion 11 only by force.

  Furthermore, in the present invention, an ink cartridge of a type that can be attached to and detached from the recording head has been described. In the case of adopting such a format, the ink supply port means a boundary region where the ink container and the recording head are connected, that is, an ink introduction port of the recording head.

FIG. 24 shows an embodiment of a liquid supply apparatus that positively utilizes the above-described operating principle of the valve body and supplies ink to the recording head while maintaining a negative pressure. In this embodiment, the valve body An ink tank containing ink, which is configured as a valve body structure 141 that closes the area upstream of 84 (the ink storage area 62 described above) while being connected to the outside by a connecting member, in this embodiment, by a hollow needle 140. The ink container 142 is removable.
The ink container 142 is formed with an ink discharge port 143 that can be liquid-tightly engaged with the hollow needle 140 at the lower portion, and for a seal (not shown) through which the hollow needle 140 can be inserted so as to prevent ink leakage when not in use. It is configured by sealing with a film. In the figure, reference numeral 144 denotes an annular packing that elastically contacts the outer periphery of the hollow needle 140, and reference numeral 145 denotes an air communication hole.
In this way, by configuring only the area necessary for the function of the valve body 84 as the valve body structure 141 independently, the recording head 146 is fixed to the bottom of the valve body structure 141, and the ink introduction port of the recording head 146 is provided. Even when 147 is connected to the ink discharge port (flow path indicated by reference numeral 86 in the figure) of the valve body structure 141, the ink container 142 is inserted and attached in the direction of reference numeral A in the figure, and moved to the opposite side. The ink can be exchanged by being pulled out, and ink can be supplied to the recording head 146.

In this embodiment as well, the effect of the valve body structure 144 is the same as that of the above-described embodiment, and it goes without saying that when the ink container 142 is integrated, it functions as the above-described ink cartridge.
In the above-described embodiment, the ink container 142 is directly connected (attached) to the connecting member (hollow needle 140), but the same may be achieved by connecting the ink cartridge installed in the recording apparatus main body with a tube. It is clear that the effects are combined.

FIG. 2 is a perspective view showing an embodiment of the ink cartridge of the present invention as seen from the ink containing area side. FIGS. 1A and 1B are a perspective view showing the same ink cartridge as seen from the other side, and a perspective view showing another embodiment of the valve body accommodating portion. It is sectional drawing which shows an ink cartridge same as the above by the cross-sectional structure of the vicinity of a negative pressure generation mechanism. FIGS. 1A to 1C are an enlarged cross-sectional view showing the valve closing state and the valve opening state of the negative pressure generating mechanism of the ink cartridge, respectively, as a cross section taken along line AA ′ of FIG. FIG. 3 is an enlarged cross-sectional view showing an ink flow path from a pressure generating mechanism to an ink supply port as a cross section taken along line AB in FIG. 2. FIGS. 1A and 1B are diagrams showing the flow of ink in the ink cartridge, respectively. FIGS. 1A and 1B are perspective views showing examples of valve bodies, respectively. It is a perspective view which shows an example of the valve body used for the conventional ink cartridge. FIGS. 1A to 1C are enlarged views showing the shapes of the convex portions of the conventional ink cartridge in the closed state, the opened state, and the closed state, respectively. It is a figure which shows the other Example which comprised the member which divides the area | region which accommodates a negative pressure generation mechanism as another member. FIG. 6 is an assembled perspective view showing another embodiment of the ink cartridge of the present invention in the structure of the opening side of the container body. It is an assembly perspective view shown with the structure of the surface side of an ink cartridge same as the above. It is a front view of the opening side of a container main body same as the above. It is a front view of the bottom part side of a container main body same as the above. It is sectional drawing of the area | region where the negative pressure generation mechanism of a container same as the above is integrated. It is sectional drawing in the flow path from the area | region where the negative pressure generation mechanism of a container same as the above is integrated to an ink supply port. It is sectional drawing which expands and shows the area | region of a negative pressure generation mechanism same as the above. It is an assembly perspective view which shows the other Example of this invention by the structure by the side of the opening of a container main body. It is sectional drawing of the area | region where the negative pressure generation mechanism of a container same as the above is integrated. It is sectional drawing which expands and shows the area | region of a negative pressure generation mechanism same as the above. FIGS. 1A and 1B are schematic views showing the flow path structure of the negative pressure generating mechanism of the ink cartridge of the present invention in a valve-closed state and a valve-open state, respectively. FIGS. 1A and 1B are schematic diagrams showing a flow path structure of a conventional negative pressure generating mechanism of an ink cartridge in a valve-closed state and a valve-open state, respectively. FIGS. 1A and 1B are diagrams schematically showing another embodiment of the flow path structure of the negative pressure mechanism of the ink cartridge of the present invention in a valve open state, respectively. It is sectional drawing which shows the other Example of a negative pressure generation mechanism. Examples of the liquid supply KyuSo location of the present invention is a cross-sectional view illustrating.

Explanation of symbols

  84 Valve body 86 Ink discharge port 88 Communication path 109 Space 140 Hollow needle 141 Valve body structure 142 Ink container 143 Ink discharge port 144 Annular packing 145 Atmospheric communication hole 146 Recording head 147 Ink introduction port

Claims (5)

A connecting member; an upstream region connected to an external ink container through the connecting member; an ink discharge port communicating with the upstream region; and a negative pressure generating mechanism that opens as ink is consumed. In the liquid supply device
The negative pressure generating mechanism is disposed between a flow path connecting the upstream region and the ink discharge port,
The negative pressure generating mechanism is
An elastic member having a first surface and a second surface, and not having a hole penetrating the first and second surfaces;
A first communication path that is provided on the first surface side of the elastic member and communicates the upstream region with the first space on the first surface side of the elastic member;
A flow path for communicating the ink discharge port with an opening provided on the first surface side of the elastic member so that the elastic member comes in contact with and separates from the first discharge port;
A second space provided on the second surface side of the elastic member, communicated with the ink discharge port via a second communication path, and communicated only with the second communication path;
With
When the elastic member receives the action of the reduced pressure on the ink discharge port side and opens the opening , ink is supplied from the upstream region to the ink discharge port through the first communication path and the opening. Liquid supply device. On the first surface side of the elastic member, a partition wall is disposed so as to form the first space between the elastic member, and a protruding portion that elastically contacts the elastic member is formed on the partition wall. The liquid supply apparatus according to claim 1, wherein the opening is formed in the protruding portion. The liquid supply device according to claim 2, wherein the elastic member is urged toward the protruding portion by an urging member disposed at a position facing the protruding portion. The liquid supply apparatus according to claim 2, wherein the elastic member is urged toward the protruding portion by its own elastic deformation force. Said opening, the liquid supply apparatus according to claim 1 which is arranged so as to face the approximate center of the elastic member.

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