JPH03101971A - Ink container, ink jet head integral with ink container, ink jet recorder with the head - Google Patents

Abstract

PURPOSE:To reduce an ink flow resistance to supply an ink stably by a method wherein a porous body inside an ink tank is out of contact with an inner wall by more than a specific ratio of the total inner area of the ink tank, and an ink is supplied with a space of a noncontact part communicating with the atmosphere. CONSTITUTION:A porous body 2 in an ink tanks is out of contact with an inner wall by the ratio of 15% or more of the total inner area of the ink tank. A space of a noncontact part formed in this manner is in a state of communicating with the atmosphere. In this construction, ribs 2600 and 270 can be molded as an integral part of the ink tank. Therefore, an ink flow resistance can be reduced, and a stable ink supply and a stable recording by a head can be accomplished without being affected by a response frequency in delivery. If, for the reasons of molding, the ribs are formed so as to block an air flow to an air communication port 5 as shown by a cross section BB, grooves are formed in the ribs to prevent the respective spaces from being sealed by an absorber independently from each other. The width and depth of the groove depend on the mechanical properties of the absorber in use, thus being determined in accordance with them.

Description

[Detailed description of the invention]

[Industrial Field of Application J] The present invention relates to an ink tank, an inkjet head, and an inkjet printer having a structure in which a porous body such as an ink absorber is housed in an ink storage container. In particular, the present invention relates to an invention that is effective for a print head that integrates a print head that ejects a print liquid and a print liquid storage section that stores the print liquid to be supplied to the print head.

[Conventional technology]

2. Description of the Related Art Conventionally, an inkjet head has been put into practical use in which an energy generating section for forming recording droplets and an ink tank for supplying ink to the energy generating section are integrated. The ink tank of this type of inkjet head generally has a structure in which a compressed porous body is impregnated with ink. The ink held in this porous body is led out from the ink tank from the ink supply port to the discharge section 4 via the common liquid chamber by the capillary force of the nozzle according to the consumption of ink in the discharge section. Conventionally, in order for the porous body to prevent negative pressure inside the ink tank, an atmosphere communication port is provided to open a small portion of the ink tank (approximately 3% of the internal area of the tank) to the atmosphere. [Problems to be Solved by the Invention] However, in conventional examples, the aim is to increase the amount of ink held in the porous body to reduce the frequency of replacement.
The proportion of porous material in the ink tank is 100%
It is being implemented in the direction of increasing towards
Despite the increase in the amount of ink being filled, the current situation is that a large amount of ink remains in the tank because it cannot be supplied for recording. In view of the current situation, the inventors of the present invention analyzed the ink retention state of the porous body, and proposed the first aspect of the present invention to provide an ink storage container that can supply ink well without adversely affecting the ejection characteristics. The second purpose is to supply an inkjet head that can perform good recording, and the third purpose is to achieve miniaturization of the recording apparatus. In addition, as a result of studies from a different perspective than the above-mentioned purpose, the present invention can significantly reduce the amount of remaining ink, and as a result, the stored ink can be efficiently supplied, downsized, and the frequency of replacement can be significantly reduced. The fourth objective is to be able to reduce the Further objects of the invention will be understood from the following description. [Means for Solving the Problems] In the present invention, as a result of studying the flow resistance of ink in the region where the porous body is in close contact with the inner wall of the ink tank, we have developed a configuration that is contrary to the conventional technical trend. Considering the distribution of resistance, the porous body in the ink tank has a structure in which the proportion of space that communicates with the atmosphere is determined between the inner wall of the ink tank and the porous body. 15% or more of the total internal area of the tank is in non-contact with the inner wall, and the non-contact space formed by this is connected to the atmosphere to supply ink, thereby reducing ink flow resistance and improving ejection speed. Stable ink supply and stable recording were achieved in the head without affecting the response frequency. Further, in the invention described in claims 4 to 8 of the present invention, each structure can provide an excellent structure that is effective in reducing the size of the structure or stabilizing the ink supply state. . [Example] Figs. 2 to 6 show a preferred inkjet unit IJU, inkjet head IJH, ink tank IT, inkjet cartridge IJC, and inkjet recording apparatus main body IJRA to which the present invention is implemented or applied.
, carriage HC and their relationships. The configuration of each part will be explained below using these drawings. As can be seen from the perspective view in Fig. 3, the inkjet cartridge IJC in this example has a large ink storage ratio, and the tip of the inkjet unit IJU protrudes slightly from the front surface of the ink tank IT. It has a shape. This inkjet cartridge IJC is fixedly supported by a positioning means and electrical contacts (described later) of a carriage HC (FIG. 5) placed on the inkjet recording apparatus main body IJRA, and is detachable from the carriage HC. It is a disposable type. The configurations shown in FIGS. 2 to 6 of this example are those to which a number of novel techniques developed at the stage of the establishment of the present invention are applied, so while briefly explaining these configurations,
I will explain the whole thing. (i) Inkjet unit IJU configuration description The inkjet unit rJU is a bubble jet unit that performs recording using an electrothermal transducer that generates thermal energy to cause film boiling in ink in response to electrical signals. be. In FIG. 2, reference numeral 100 is composed of electrothermal converters (discharge heaters) arranged in a plurality of rows on a Si substrate, and electrical wiring such as A42 for supplying electric power to the converters, which are formed by film-forming technology. It's a heater board. 200 is a wiring board for the heater board 100;
Wiring corresponding to the wiring of the heater board 100 (for example, connected by wire bonding) and a pad 201 located at the end of this wiring and receiving electrical signals from the main device.
It has 1300 is a grooved top plate provided with partition walls for dividing a plurality of ink channels and a common liquid chamber for storing ink to supply ink to each ink channel, and is supplied from an ink tank IT. An ink receiving port 1500 that receives ink and introduces it into the above-mentioned common liquid chamber, and an orifice plate 400 having a plurality of ejection ports corresponding to each ink flow path are integrally molded. Although polysulfone is preferable as the integrally molded material, other resin materials for molding may also be used. Reference numeral 300 denotes a support made of metal, for example, which supports the back surface of the wiring board 200 on a flat surface, and serves as a bottom plate of the inkjet unit. Reference numeral 500 denotes a pressing spring, which is M-shaped and presses the common liquid chamber with light pressure at the center of the M-shape, and concentrates linear pressure on a part of the liquid path at the front part 501, preferably in the area near the discharge port. Press. The foot of the spring that presses the heater board 100 and the top plate 1300 passes through the hole 3121 of the support body 300 and engages with the back side of the support body 300, thereby engaging the two in a state where they are sandwiched between them. The heater board 100 and the top plate 1300 are crimped and fixed by the concentrated biasing force of the spring 500 and its front sagging portion 501. The support body 300 also has positioning holes 312, 1900, 2000 that engage with the two positioning protrusions 1012 and the positioning and heat-sealing holding protrusions 1800, 1801 of the ink tank IT.
Protrusions 2500 and 2600 for positioning the apparatus main body IJRA with respect to the carriage HC are provided on the back side. In addition, the support 300 also has a hole 320 that allows an ink supply pipe 2200 (described later) to pass therethrough, which allows ink to be supplied from an ink tank. The wiring board 200 is attached to the support body 300 by adhering it with an adhesive or the like. Note that the recesses 2400 and 2400 of the support body 300 are provided near the positioning protrusions 2500 and 2600, respectively, so that the assembled inkjet cartridge IJ
C (Fig. 3), the three sides around it are parallel grooves 300.
At the extension point of the head tip region formed by a plurality of projections 2500.2, dust and ink are
It is located so that it does not reach 600. This parallel groove 3000 is featured. As seen in FIG. 5, the lid member 800 forms the outer wall of the inkjet cartridge IJC, and together with the ink tank forms a space in which the inkjet unit IJU is accommodated. In addition, the ink supply member 600 in which the parallel grooves 3001 are formed has the ink conduit 1600 continuous to the ink supply pipe 2200 described above formed as a cantilever with the supply pipe 2200 side fixed, and the fixed side of the ink conduit and Sealed bottle 602 to ensure capillary action with ink supply tube 2200
is inserted. Note that 601 is a packing that seals the connection between the ink tank IT and the supply pipe 220σ, and 700 is a filter provided at the tank side end of the supply pipe. Since the ink supply member 600 is molded, it is not only inexpensive and has high positional accuracy and eliminates deterioration in manufacturing precision, but also cantilevered conduit 1600 allows the conduit 1600 to be easily adjusted during mass production. The state of pressure contact with the ink socket 1 500 described above can be stabilized. In this example, a more complete communication state can be reliably obtained by simply pouring the sealing adhesive from the ink supply member side under this pressure-contact state. Note that the ink supply member 600 is fixed to the support body 300 through the hole 1901 of the support body 300.
．． This can be easily done by projecting the backside bottle (not shown) of the ink supply member 600 to 1902 through the holes 1901 and 1902 of the support 300, and heat-sealing the protruding portion to the backside of the support 300. be exposed. Note that this slightly protruding area of the heat-sealed back surface is the ink tank I.
Since it is housed in a recess (not shown) in the side wall surface of the inkjet unit IJU mounting surface of the T, the positioning surface of the unit IJU can be accurately obtained. (if) Ink tank IT configuration description The ink tank is constructed by inserting the cartridge body 1000, ink absorber 900, and ink absorber 900 from the side of the cartridge body 1000 opposite to the unit IJU mounting surface. and a lid member 1100 for sealing. Reference numeral 900 denotes an absorber for impregnating ink, and is disposed within the cartridge body 1000. 1 200 is a supply port for supplying ink to the unit IJU consisting of the above-mentioned parts 100 to 600, and ink is supplied from the supply port 1200 in a step before placing the unit in the portion 1010 of the cartridge body 1000. It is also an injection port for impregnating the absorber 900 with ink. In this example, the parts that can supply ink are the atmosphere communication port and the supply port, but the rib 2300 in the main body 1000 is used to ensure good ink supply from the ink absorber.
and the partial ribs 2500 and 2400 of the lid member 1100.
Since the ink is continuously formed from the 40l side and extends over the farthest corner area from the ink supply port 1200, a relatively good and uniform ink supply to the absorber is achieved.
It is important that this is done from the supply port 1 200 side. This method is extremely effective in practice. This rib 100
0 has four ribs parallel to the carriage movement direction on the rear surface of the ink tank main body 1000 to prevent the absorber from coming into close contact with the rear surface. Further, the partial ribs 2400 and 2500 are similarly provided on the inner surface of the lid member 1100 on corresponding extensions to the rib 1000, but unlike the rib 1000, they are in a divided state and prevent air from entering. The existence space is increased compared to the former. Note that the partial ribs 2500 and 2400 are distributed over a surface that is less than half of the total area of the lid member 1000. These ribs allow the tank supply port 1200 of the ink absorber to
The ink in the corner region farthest from the ink could be more stably guided to the supply port 1200 side by capillary force. Reference numeral 1401 denotes an air passage port provided in the lid member to communicate the inside of the cartridge with the atmosphere. Reference numeral 1400 denotes a liquid-repellent material disposed inside the atmosphere communication port 1401, which prevents ink from leaking from the atmosphere communication port 1400. The ink storage space of the ink tank IT mentioned above has a rectangular shape, and the long sides are on the sides, so the arrangement of the ribs described above is particularly effective. In the case of a case or a cube, cover member 1
By providing ribs throughout the ink absorber 900, the ink supply from the ink absorber 900 can be stabilized. A rectangular parallelepiped shape is suitable for storing as much ink as possible within a limited space, but in order to use the stored ink for recording without wasting it, as mentioned above, it is necessary to It is important to provide ribs that can perform the above-mentioned action on two adjacent surface areas. Furthermore, the inner surface ribs of the ink tank IT in this embodiment are arranged in a substantially uniform distribution in the thickness direction of the rectangular parallelepiped-shaped ink absorber. This configuration is important because it can equalize the atmospheric pressure distribution and almost eliminate the remaining amount of ink with respect to the ink consumption of the entire absorber. Furthermore, to explain in detail the technical idea behind the arrangement of the ribs, when an arc is drawn with the long side as the radius and centered on the position where the ink supply port 1200 of the ink tank is projected on the quadrangular top surface of the rectangular parallelepiped, ,
It is important to arrange the ribs on the surface outside the arc so that the atmospheric pressure can be quickly applied to the absorbent body located outside the arc. In this case, the atmosphere communication port of the tank is not limited to this example, as long as it is at a position where the atmosphere can be introduced into the rib arrangement area. In addition, in this embodiment, the inkjet cartridge I
The rear surface of the JC head is flattened to minimize the space required when incorporated into the device, and the structure maximizes the ink storage capacity, resulting in a more compact device. Not only that, but it also has an excellent structure that reduces the frequency of cartridge replacement. Then, by utilizing the rear part of the space for integrating the inkjet unit IJU, a protruding part for the atmosphere communication port l401 is formed there, and the inside of this protruding part is hollowed out, and the above-mentioned absorption An atmospheric pressure supply space 1402 is formed over the entire thickness of the body 900. With this configuration, we were able to provide an excellent cartridge that has never been seen before. Note that this atmospheric pressure supply space 1402 is much larger than the conventional one, and the atmospheric communication port 1401 is located above, so even if the ink leaves the absorber due to some abnormality, this large space will not be affected. The air pressure supply space 1402 can temporarily hold the ink and ensure that the ink is collected by the absorber, so that an excellent cartridge with no waste can be provided. Further, the structure of the mounting surface of the unit IJU of the ink tank IT is shown in FIG. Let L be a straight line that passes approximately through the center of the protrusion of the orifice plate 400 and is parallel to the mounting reference plane on the bottom of the tank IT or the surface of the carriage.
The two positioning protrusions 1012 are on this straight line L. The height of this protrusion 1012 is slightly lower than the thickness of the support 300, and positions the support 300. In this drawing, on the extension of the straight line L, there is a hook 4 for positioning the carriage.
001's 90@corner engagement surface 4002 engages with the claw 2l0
0 is located, and the positioning force for the carriage is configured to act on a plane region parallel to the reference plane that includes this straight line L1. As will be described later with reference to FIG. 5, these relationships are effective because the positioning accuracy of only the ink tank is equivalent to the positioning accuracy of the ejection ports of the head. Further, a hole 19 for fixing the support body 300 to the side surface of the ink tank is provided.
Ink tank protrusion tg corresponding to 00.2000 respectively
oo and isoi are longer than the above-mentioned protrusions 1012, and the parts that penetrate through the support 300 are heat-sealed to form the support 3.
This is for fixing 00 to its side. The above line L. Let Ls be a straight line that is perpendicular to the line and passes through this protrusion 1800, and L2 is a straight line that passes through the protrusion 180l. Since the approximate center of the supply port 1 200 is located above the straight line L, the supply port 1200 and the supply This is a preferable configuration because it acts to stabilize the state of connection with the pipe 2200 and reduces the load on these connections even if dropped or impacted. or,
straight line L. ,L. Since the protrusions 1800 and 1801 are present around the convex protrusion 1012 on the ejection port side of the head IJH, this further produces a reinforcing effect in positioning the head IJH with respect to the tank. Note that the curve indicated by L4 is the outer wall position when the ink supply member 600 is attached. Since the protrusions 1800 and 1801 are along the curve L4, they provide sufficient strength and positional accuracy even for the weight of the distal end side configuration of the head IJH. Reference numeral 2700 denotes a tip collar of the ink tank T, which is inserted into a hole in the front plate 4000 of the carriage and is provided in case of an abnormal situation where the displacement of the ink tank becomes extremely poor. Reference numeral 2101 is a retainer for the carriage, which is provided to a bar (not shown) of the carriage HC, and is provided to a bar (not shown) of the carriage HC.
This is a protective member for maintaining the mounted state even if a force is applied in the upward direction that causes the JC to enter the lower part of the bar at the pivoted mounted position and unnecessarily disengage from the positioned position as will be described later. The ink tank IT has a shape that surrounds the unit IJU except for the lower opening by covering it with a lid 800 after the unit E JU is installed. Since the lower opening is close to the carriage HC, it forms a substantial four-sided surrounding space. Therefore, although the heat generated from the head IJH in this enclosed space is effective as a heat-retaining space, the temperature rises only slightly during long-term continuous use. For this reason, in this example, a slit 1700 with a width smaller than this space is provided on the upper surface of the cartridge IJC in order to aid the natural heat dissipation of the support, thereby preventing a rise in temperature and ensuring a uniform temperature distribution throughout the unit IJU. We were able to make the process unaffected by the environment. When assembled as an inkjet cartridge IJC, ink is supplied from inside the cartridge through the supply port 1 200,
Hole 320 in support 300 and supply tank 600
The ink is supplied into the supply tank 600 through an inlet provided on the inside back side, and after passing through the interior, it enters the common liquid chamber from an outlet through an appropriate supply pipe and an ink inlet 1500 of the top plate 400. and inflow. A packing made of, for example, silicone rubber or butyl rubber is disposed at the above-mentioned connection portion for ink communication, and this seals the ink supply path to ensure an ink supply path. In this embodiment, the top plate 1300 is made of a resin such as polysulfon, polyethersulfon, polyphenylene oxide, or polypropylene, which has excellent ink resistance, and is molded together with the orifice plate part 400 in a mold. It has been done. As mentioned above, the integrally molded parts include the ink supply member 600,
Top plate and orifice plate integrated, ink tank body 1
000, which not only achieves a high level of assembly accuracy but also is extremely effective in improving quality in mass production. Furthermore, since the number of parts can be reduced compared to the prior art, excellent desired characteristics can be reliably exhibited. In addition, in the embodiment of the present invention, in the above-mentioned shape after assembly,
As shown in FIGS. 2 to 4, the ink supply member 6
00, the upper surface part 603 is the third one between the end part 4008 of the roof part provided with the slit 1700 of the ink tank IT.
As shown in the figure, a slit S (not shown) similar to the slit S is formed between the lower surface portion 604 and the head side end portion 4011 of the thin plate member to which the lower lid 800 of the ink tank IT is bonded. ) is formed. These slits between the ink tank IT and the ink supply member 600 substantially act to further promote heat dissipation from the slit 1700, and even if there is unnecessary pressure applied to the tank IT, it is directly supplied. This prevents any damage to the members, or even the inkjet unit IJT. In any case, the above-mentioned configuration of this embodiment is a configuration that has not existed in the past, and while each of them individually provides an effective effect, each configuration or requirement can be combined to create an organic configuration. is bringing. (iiL) Description of attachment of inkjet cartridge rJc to carriage HC In FIG. 5, 5000 is a platen roller that guides the recording medium P from the bottom to the top of the page. The carriage HC moves along the platen roller 3000, and has a front plate 40 located on the front side of the inkjet cartridge IJC on the front platen side of the carriage.
00 (thickness: 2 mm) and a flexible sheet 4005 equipped with pads 2011 corresponding to the pads 201 of the wiring board 200 of the cartridge IJC, and for generating elastic force to press this against each pad 2011 from the back side. A support plate 4003 for the electrical connection part that holds the rubber pad sheet 4007 of the inkjet cartridge IJ.
Positioning hook 400 for fixing C to the recording position
1 is provided. The front plate 4000 has two positioning projecting surfaces 4010 corresponding to the aforementioned positioning projections 2500 and 2600 of the cartridge support 300, respectively, and receives a vertical force toward these projecting surfaces 4010 after the cartridge is mounted. For this reason, the front plate has a plurality of reinforcing ribs (not shown) on the platen roller side facing in the direction of the perpendicular force. This rib is located at the front position L when the cartridge IJC is installed.
A head protection protrusion that protrudes slightly (approximately 0.1 mm) toward the platen roller is also formed. The electrical connection support plate 4003 has a plurality of reinforcing ribs 4004 not in the direction of the ribs but in the vertical direction, and the proportion of lateral protrusion is reduced from the platen side toward the hook 4001 side. This also serves the function of tilting the position when the cartridge is installed as shown in the figure. In addition, in order to stabilize the electrical contact state, the support plate 4003 is used to position the hook side to apply force to the cartridge in the opposite direction to the direction in which the two positioning protruding surfaces 4010 act on the cartridge. It has two surfaces 4006 corresponding to the protruding surfaces 4010, forming a pad contact area between these surfaces and uniquely defining the deformation amount of the bulge of the rubber seat 4007 corresponding to the pad 2011. These positioning surfaces come into contact with the surface of the wiring board 300 when the cartridge IJC is fixed at a recordable position. In this example, the wiring board 300
Since the pads 201 are distributed symmetrically with respect to the above-mentioned line L, the amount of deformation of each hole of the rubber sheet 4007 is made uniform, and the contact pressure of the pads 2011 and 201 is made more stable. The distribution of pads 201 in this example is two rows above, two rows below, and two columns vertically. The hook 4001 has an elongated hole that engages with the fixed shaft 4009, and uses this elongated movement space to rotate counterclockwise from the position shown in the figure, and then moves to the left along the platen roller 5000. By doing so, the inkjet cartridge IJC is positioned with respect to the carriage HC. The hook 4001 may be moved by any method, but it is preferable to use a lever or the like. In any case, when the hook 4001 rotates, the cartridge IJC moves toward the platen roller and moves to a position where the positioning projections 2500 and 2600 can come into contact with the positioning surface 4010 of the front plate,
By moving the hook 400 1 to the left, the 90" hook surface 4002 is attached to the 90@ of the claw 2100 of the cartridge rJc.
Position the cartridge IJC while keeping it in close contact with the surface 250.
The pads rotate in a horizontal plane around the contact area of the pads 201 and 2010, and finally contact between the pads 201 and 2011 begins. When the hook 400 1 is held in a predetermined position, that is, a fixed position, the pads 201 and 2011 are in complete contact with each other, the positioning surfaces 2500 and 4010 are in complete surface contact, and the 90-degree surface 4002 and the 90-degree surface of the claw are brought into contact with each other. The two-surface contact between the two surfaces and the surface contact between the wiring board 300 and the positioning surface 4006 are simultaneously formed, and the holding of the cartridge IJC in the carriage is completed. (iv) General description of the main body of the apparatus FIG. 6 shows an inkjet recording apparatus I to which the present invention is applied.
In the general view of JRA, the carriage HC that engages with the spiral groove 5004 of the lead screw 5005, which rotates via the drive force transmission gears 5011 and 5009 in conjunction with the forward and reverse rotation of the drive motor 5013, is a pin (not shown). ) and is moved back and forth in the directions of arrows a and b. Reference numeral 5002 denotes a paper holding plate that holds the paper on the platen 5 in the direction of carriage movement.
0 0 0 Press against 2. 5007.5008
is home position detection means for confirming the presence of the lever 5006 of the carriage in this area using a photocoupler and switching the rotational direction of the motor 5013. 5016
is a cap member 502 that caps the front surface of the recording head.
2, and 5015 is a suction means for suctioning the inside of this cap, and performs suction recovery of the recording head through an opening 5023 in the cap. 5017 is a cleaning blade, 5019 is a member that allows this blade to move in the front and rear directions, and these are supported by a main body support plate 5018. Needless to say, the blade is not of this type, but a well-known cleaning blade can be applied to this example. Further, 5o12 is a lever for starting the suction for recovery of the bow, and it moves with the movement of the cam 502o that engages with the carriage, and the driving force from the drive motor is transferred by known transmission means such as clutch switching. controlled. These capping, cleaning, and suction recovery operations are configured so that when the carriage reaches the home position side area, the desired processes can be performed at the corresponding positions by the action of the lead screw 5005. Any of the above operations can be applied to this example. Each of the configurations described above is an excellent invention whether viewed singly or in combination, and represents a preferable configuration example for the present invention. In order to explain in detail the present invention technically related to the above-mentioned FIGS. 2 to 6, the following description will be made using FIGS. 1 and 7 and subsequent figures. FIG. 1 shows ribs 260 and 27 on the inner wall of the ink tank 1 so as to have a space communicating with the atmosphere communication port 5, as in the previous embodiment.
0 is provided, and the shape is different from that shown in the figure. In this example, the ink tank internal porous body 2 is not in contact with the inner wall of 15% or more of the total inner area of the ink tank, and
The non-contact space thus formed is in communication with the atmosphere, and the ribs 2600, 270 are similar to the above.
has a structure that can be integrally molded with the ink tank. Therefore, the ink flow resistance is reduced and the ink supply is stable without affecting the ejection response frequency.
A stable record was achieved. By providing the ribs as shown in the cross sections AA and BB in FIG. 1(b), the ink tank does not come into close contact with the inner wall of the ink tank, and a space communicating with the atmosphere communication port 5 can be secured. For convenience of molding, as shown in cross section BB,
If a rib is provided for the air communication port to block the flow of air, grooves are provided in the rib as shown in the figure so that each space is sealed by the absorber so that they are not independent. The inside and depth of this groove varies depending on the mechanical properties of the absorbent body used, and is determined accordingly. Furthermore, Figure 1 (
As shown in e), in this embodiment, although the space area behind the head 4 (approximately 3%) has the conventional structure in which the absorber 2 is intruded, the total internal area of the ink tank as a whole is The above-mentioned effect is obtained because the inner wall of 15% or more of the inner wall is not in contact with the inner wall. FIG. 11 shows the ejection characteristics in this case. As shown in the figure, conventionally, when the open area is 3% of the total ink tank, the response frequency decreases. Due to the decrease in the response frequency, the discharge amount becomes extremely small (as shown in the upper diagram of Fig. 11).
Decrease print quality. Furthermore, in the case of high duty, the ejection may not be able to follow up and the ejection may fail. However, by increasing the open area of the absorber to the atmosphere, the flow of ink within the absorber becomes easier, and as long as 15% or more is ensured as shown in the figure, it will not affect ejection. Forming such an atmosphere communication area of 15% or more does not depend on the position of the surface inside the ink tank, so the above-mentioned area is formed on the side, top, and bottom of the ink tank that communicates with the atmosphere communication port. A structure may be provided to ensure a bonding area with the atmosphere. Of course, it is a more preferable configuration to form an air permeability area of 15% or more in the configurations described in FIGS. 2 to 6 above. Other embodiments are shown in FIGS. 7 to 10. FIG. 8 shows an ink tank in which ribs 30 are provided radially on the top surface of the ink tank for communication with the atmosphere. With this configuration, it is possible to adjust the proportion of air present in the central area and side areas of the enlarged absorber, which is a preferable configuration. one of. Fig. 9 shows a cylindrical protrusion, and Fig. 10 shows a part with a U-shaped cross section, which is attached to the inner wall of the tank as shown in the figure, so that a contact area can be obtained through a communicating path. In FIG. 7, in (a), in the case of an absorber with very little atmospheric transport, the atmospheric transport area is formed after the start of use by the route that forms the shortest distance toward the ink supply pipe 2200 to the head. , you can understand the situation where the ink held by the absorber is not supplied and remains. (b) and (c) are explanatory diagrams when the formation surface of the air transport region of the present invention is developed. As in the above embodiment, first, the rear part of the space for integrating the ink jet into the ink storage container is shown. In the case where a protruding part for an atmosphere communication port is formed there using the above-mentioned porous body, and the inside of this protruding part is hollowed out to form an atmospheric pressure supply space 1402 for the entire thickness of the porous body, (a) Compared to the above, the atmospheric pressure supply space 1402 over the entire thickness of the porous body can uniformize the ink supply in the thickness direction, and therefore exhibits an overall superior partial effect. In addition to this, the atmospheric pressure supply space 20 formed on the rear surface with respect to the head 4 decentralizes the above route,
Since it extends to the opposite corner of the supply area, it can be seen that the path to the supply ready state is wide open for the area that is least likely to be consumed. In addition, when the area 21 on the opposing surface of the air communication port, which is outside the area whose radius is the shortest distance r between the supply area and the area where the air is not communicated, is placed in the air communication state, the route 22 is further shaped. It will be understood that since this state is enabled, the ink absorbed in the porous body 2 can be stably and reliably supplied to the head 4. In particular, in (c), the supply area and the area in the atmospheric transport state are placed opposite each other, so the area outside the shortest distance r is lateral 2
11,222, so the effects of the present invention can be obtained by bringing these areas into the atmospheric transport state. The present invention provides excellent effects particularly in bubble jet recording heads and recording apparatuses among ink jet recording systems. As for typical configurations and principles thereof, it is preferable to use the basic principles disclosed in, for example, US Pat. No. 4,723,129 and US Pat. No. 4,740,796. This method can be applied to both the so-called on-demand type and continuous type, but especially in the case of the on-demand type, it is necessary to arrange the liquid (ink) in accordance with the sheet and liquid path that hold it. As an electrothermal converter,
By applying at least one drive signal corresponding to recorded information and providing a rapid temperature rise above nucleate boiling, the electrothermal transducer generates thermal energy to cause film boiling on the thermally active surface of the recording head. As a result, bubbles in the liquid (ink) can be formed in one-to-one correspondence with this drive signal, which is effective. The growth and contraction of the bubble causes liquid (ink) to be ejected through the ejection opening to form at least one drop. It is more preferable to use this drive signal in a pulse form, since the growth and contraction of bubbles can be carried out immediately and appropriately, so that ejection of liquid (ink) with particularly excellent responsiveness can be achieved. As this pulse-shaped drive signal, those described in US Pat. No. 4,463,359 and US Pat. No. 4,345,262 are suitable. Incidentally, U.S. Patent No. 431 for the invention regarding the temperature increase rate of the heat acting surface
If the conditions described in specification No. 3124 are adopted,
Even better recording can be performed. The configuration of the recording head includes, in addition to the combined configuration of ejection ports, liquid paths, and electrothermal converters (straight liquid flow path or right-angled liquid flow path) as disclosed in the above-mentioned specifications, a heat acting section. US Pat. No. 4,558,333 and US Pat. No. 4,459,600 disclose a configuration in which the
The present invention also includes a configuration using the specification of the above specification. In addition, Japanese Patent Application Laid-Open No. 123670 of 1981 discloses a structure in which a common slit is used as a discharge part of a plurality of electrothermal converters, and a method for absorbing pressure waves of thermal energy is disclosed. The present invention is also effective as a configuration based on Japanese Patent Application Laid-Open No. 138461 of 1982, which discloses a configuration in which the openings correspond to the discharge portions. Furthermore, as a full-line type recording head having a length corresponding to the width of the maximum recording medium that can be recorded by the recording device, the length can be increased by combining multiple recording heads as disclosed in the above-mentioned specification. Either a configuration that satisfies the above requirements or a configuration as a single recording head formed integrally may be used, but the present invention can more effectively exhibit the above-mentioned effects. In addition, a replaceable chip-type recording head that is attached to the device body enables electrical connection to the device body and ink supply from the device body, or a chip-type recording head that is installed integrally with the recording head itself. The present invention is also effective when a cartridge type recording head is used. Further, it is preferable to add recovery means, preliminary auxiliary means, etc. for the recording head, which are provided as a configuration of the recording apparatus of the present invention, because the effects of the present invention can be further stabilized. Specifically, these include preheating means for the recording head using a caving means, a cleaning means, a pressurizing or suction means, an electrothermal transducer or another heating element, or a combination thereof. It is also effective to perform a preliminary ejection mode in which ejection is performed separately from printing in order to perform stable printing. Furthermore, the recording mode of the recording device is not limited to a recording mode in which only the mainstream color such as black is used; the recording head may be configured integrally or in combination with a plurality of recording heads; The present invention is also extremely effective for devices equipped with at least one full color image. [Effects of the Invention] As described above, according to the invention in which 15% or more of the inner surface area of the ink tank is exposed to the atmosphere, good ejection characteristics can be obtained without decreasing the response frequency, and good printing is possible. became. Further, the ink supply of the porous body formed by the atmospheric communication port is centered at a position where the ink supply port is projected with respect to the upper surface in the ink flow direction from the atmospheric communication port to the ink supply port. According to the invention, the porous body forms an atmospheric communication space on the inner surface of the side wall of the ink storage container corresponding to an area that is at least the distance from the nearest area to the projected position of the mouth. Since ink can be consumed without waste, miniaturization can be achieved. Other effects of the present invention can be understood from the above description.

[Brief explanation of drawings]

1(a) to (f) are explanatory diagrams of an embodiment of the present invention, FIG. 2 is an exploded perspective view of the cartridge of the present invention, FIG. 3 is an assembled perspective view of FIG. 2, and FIG. A perspective view of the attachment part of the inkjet unit IJU, FIG. 5 is an explanatory diagram of the attachment of the cartridge JC to the device, FIG. 6 is an external view of the device of the present invention, FIG. 7 is an explanatory diagram of ink flow, and FIGS. 8 to 10 The figures are perspective views of other embodiments of the present invention, and FIGS. 11(a) and 11(b) are discharge characteristic diagrams. 1... Ink tank 2... Absorber (porous body) 3... Supply port 4... Discharge part 5... Atmospheric communication port 6... Electrical contact part L3 72ft) 1 and'/ l) 1st and fig. / 7401 th 〃 fig. Jσ

Claims (8)

[Claims] (1) An ink storage container having an atmosphere communication port and an ink discharge part for supplying ink to the outside of the container at different positions, and in which a porous body is stored in the container for holding ink. In the storage container, the porous body in the ink tank is in non-contact with an inner wall that accounts for 15% or more of the total internal area of the ink tank, and the non-contact space formed thereby is in communication with the atmosphere to store ink. An ink storage container characterized by supplying ink. (2) An ink storage container that has an atmosphere communication port and an ink supply port for supplying to an inkjet head at different positions, and is integrated with the ink storage container filled with a porous material to store ink. An inkjet head formed in an inkjet head having an ejection portion that ejects ink using an ejection energy generating means provided in a liquid path,
In an inkjet head in which an ejection energy generating means operates in response to a predetermined electric signal, the porous body in the ink tank is formed by not contacting an inner wall of 15% or more of the total inner area of the ink tank. An inkjet head characterized in that ink is supplied while a non-contact space is in communication with the atmosphere. (3) An ink storage container having an atmosphere communication port and an ink supply port for supplying ink to the inkjet head at different positions, and filled with a porous material to store ink; and an ink storage container filled with a porous material to store ink; An inkjet recording apparatus that performs recording by including an inkjet head equipped with an ejection unit that ejects ink using an ejection energy generating means provided in a liquid path, the ink storage container and the inkjet head. a carriage for placing the inkjet head on the side of the ink storage container for reciprocating the inkjet head, and means for supplying an electric signal to the ejection energy generating means, and the porous body in the ink tank comprises: 1 of the total internal area of the ink tank
An inkjet recording apparatus characterized in that the non-contact space formed by the inner wall is in contact with 5% or more of the inner wall and ink is supplied while the non-contact space is in communication with the atmosphere. (4) An ink storage container that has an atmosphere communication port and an ink supply port for supplying to an inkjet head at different positions, and is integrated with the ink storage container filled with a porous material to store ink. An inkjet head formed in an inkjet head having an ejection portion that ejects ink using an ejection energy generating means provided in a liquid path,
In an inkjet head in which an ejection energy generating means is operated in response to a predetermined electric signal, the porous body has a substantially rectangular parallelepiped shape, and the porous body has the above-mentioned shape with respect to the upper surface in the ink flow direction from the atmosphere communication port to the ink supply port. A side wall portion of the ink storage container that corresponds to an area that is centered on a projected position of the ink supply port and that corresponds to an area that is at least a distance from the nearest region of the porous body formed by the atmospheric communication port to the projected position of the ink supply port; An inkjet head characterized in that the porous body has a member on its inner surface that can form an atmosphere communication space with the inner surface. (5) An ink storage container that has an atmosphere communication port and an ink supply port that supplies the ink to the inkjet head at different positions, and is filled with a porous material to store ink; and an ink storage container that is filled with a porous material to store ink; An inkjet recording apparatus that performs recording by including an inkjet head equipped with an ejection unit that ejects ink using an ejection energy generating means provided in a liquid path, the ink storage container and the inkjet head. a carriage for placing the inkjet head on the side of the ink storage container for reciprocating the inkjet head, and means for supplying an electric signal to the ejection energy generating means, the atmosphere communication port and the ink supply port. is located on the lateral side above,
A non-contact space that is not in contact with the inner wall of the ink storage container and is in communication with the atmosphere is a part of the surface facing the atmosphere communication port and a part of the surface facing the atmosphere communication port. An inkjet recording device characterized in that an inkjet recording device exists on three surfaces: and a surface connecting these surfaces. (6) A protruding portion provided at the rear of the space for integrating the inkjet head with the ink storage container and having the atmospheric communication port formed therein; 6. The inkjet recording apparatus according to claim 5, wherein an atmospheric pressure supply space is formed for the entire thickness of the body. (7) The ejection energy generating means is a thermal energy generating means, and the means for supplying the electric signal performs recording by supplying the generating means with a drive signal that causes film boiling in the ink. The inkjet recording device according to item 6. (8) An ink storage container having an atmosphere communication port and an ink supply port for supplying to an inkjet head at different positions, and is integrated with the ink storage container filled with a porous material to store ink. An inkjet head formed in an inkjet head having an ejection portion that ejects ink using an ejection energy generating means provided in a liquid path,
In an inkjet head in which an ejection energy generating means is operated in response to a predetermined electric signal, a protruding part for an atmosphere communication port is formed in the rear part of the space for integrating the inkjet into the ink storage container. An inkjet head characterized in that the inside of the protruding portion is hollowed to form an atmospheric pressure supply space to the entire thickness of the porous body.