JPH06183020A - Ink storage tank, ink jet head cartridge equipped with the tank, and ink jet recorder equipped with the cartridge - Google Patents

Abstract

PURPOSE:To allow positive ink supply from an ink storage tank to a recording head, as required. CONSTITUTION:An ink bag 4 for holding ink therein is coupled with a part 5 for supplying ink, as required, from the ink bag 4 to a recording head part 2. The supply part 5 is equipped with a slit bladder made of elastic member having a slit 7a which is normally closed but opened upon occurrence of predetermined pressure difference between the ink bag 4 and the recording head part 2, and a fixing base 6 to be fit with the peripheral part of the slit bladder 7. The slit bladder 7 abuts on a protrusion 8b formed on a bladder cover 8 to be imparted with initial deformation. Since the split bladder 7 is depressed easily by negative pressure at the recording head part 2, negative pressure at the recording head part 2 is sustained within a predetermined range and thereby the ink is fed more stably to the recording head part 2.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink having an ink storage section for holding the ink therein and a supply section for supplying the ink held in the ink storage section to the outside as needed. The present invention relates to a storage tank, an inkjet head cartridge including the ink storage tank, and an inkjet recording apparatus including the inkjet head cartridge.

[0002]

2. Description of the Related Art In general, an ink jet head cartridge in which a recording head portion having an ejection port for ejecting ink and an ink storage tank for holding ink supplied to the recording head portion are integrally provided ( Less than,
In the "cartridge"), the ink held in the ink storage unit is transferred from the ink storage tank to the recording head due to the capillary phenomenon in the ink flow path in the recording head unit and the negative pressure in the recording head unit generated by the ink ejection. A predetermined amount is supplied into the unit.

Therefore, the ink storage tank can sufficiently supply the ink to the recording head portion, and the ink held in the ink storage tank is carelessly supplied to the recording head portion so as not to leak to the outside from the ejection port or the like. It is necessary to have an appropriate ink holding power (negative pressure), and the following cartridges are known as conventional cartridges.

(1) A method in which an absorber made of a porous material impregnated with ink is compressed and stored in an ink storage tank, and a negative pressure is generated in the ink storage tank by the ink absorbing power of the absorber (for example, , JP-A-63-87242).

(2) The ink storage tank is provided with a bladder in which the ink is held, and when the bladder is crushed due to the consumption of the ink in the bladder, the restoring force of the bladder is used to make the ink storage tank inside. A device for generating a negative pressure (for example, JP-A-59-207263).

(3) The ink storage tank is integrally provided with a valve body which is a supply portion, the valve body is formed with a through hole communicating with the ink storage tank, and further, the valve head is moved by a negative pressure of the recording head portion. A valve provided with an elastic member for opening and closing the through hole is provided (for example, Japanese Patent Laid-Open No. 62-231759).

(4) An equivalent of an ink storage tank has an ink bag for storing ink and a bladder for generating negative pressure, and further connects the ink bag and the bladder. Or (filling mode), communicating the bag with the recording head (printing mode), ink bag,
Neither the sac nor the recording head section are in communication (closed mode)
It has a three-way valve that can be switched to. Then, during non-recording, the three-way valve is set to the closed mode, and at the time of recording, the three-way valve is switched to the print mode to use the ink in the capsule. At this time, a negative pressure is generated by the restoring force of the capsule. When the ink in the bladder is exhausted, the three-way valve is switched to the filling mode, and the bladder is filled with the ink from the ink bag (for example, JP-A-63-172654).

[0008]

However, in each of the above-described embodiments (1) and (2), although the structure of the ink storage tank is simple, there is a negative pressure in the ink storage tank. When the value is less than the value, ink leaks from the ejection port, and when the ink in the ink storage tank decreases due to the ejection of ink, the negative pressure in the ink storage tank increases, which exceeds a certain range. In this case, the ink is not supplied to the recording head unit, and the ink remains in the ink storage tank. Furthermore, especially (1)
In the case of (1), the ratio of the ink amount to the volume of the ink storage tank becomes low, and in the case of (2), in the case of the cartridge mounted in the serial type recording device, the movement of the carriage mounting the cartridge Since the ink in the ink storage tank vibrates and the inside of the bladder is momentarily pressurized, it is easy to cause ink leakage from the ejection port.

Further, in the cases of (3) and (4), almost all the ink in the ink storage tank can be used for recording, but the number of constituent parts increases and the structure becomes complicated. Especially in the case of (3), it is difficult to move the valve stably only by the negative pressure of the recording head section.
In the case of (4), a means for controlling the switching of the three-way valve is required separately, so that the overall system becomes more complicated.

An object of the present invention is to provide an ink storage tank which can reliably supply the ink in the ink storage portion to the recording head portion when necessary and has a simple structure, an ink jet head cartridge equipped with the ink storage tank, and the ink jet ink jet head cartridge. An object is to provide an inkjet recording device including a head cartridge.

[0011]

In order to achieve the above object, an ink storage tank of the present invention is provided with an ink storage section for storing ink therein, and an ink stored in the ink storage section, if necessary. In an ink storage tank having a supply unit for supplying to the outside, the supply unit is closed in a steady state, and a slit that opens when a predetermined differential pressure is generated between the ink storage unit and the outside. A partition member formed of an elastic member, a base member to which a peripheral portion of the partition wall is attached, in which an ink flow path is formed, and a part of the partition wall are brought into contact with each other to apply initial deformation to the one part of the partition wall. And a protruding portion.

Further, the supply section is provided with a cover member for covering the partition wall, and the projection section is provided on the cover member, or the partition wall is a hollow dome shape in which at least the top is hemispherical. A slit may be formed on the top portion, and the protrusion may be in contact with a part of the partition wall in the range of 0 to 35 ° with respect to the longitudinal direction of the slit.

An ink jet head cartridge of the present invention is characterized by having the ink storage tank of the present invention and a recording head portion connected to the ink storage tank for ejecting ink from an ejection port.

The recording head unit is of a full line type in which ejection openings are formed over the entire width of the recording area of the recording medium, or ejects ink by utilizing thermal energy. It may have an electrothermal converter as an energy generating element for generating.

The ink jet recording apparatus of the present invention has the ink jet head cartridge of the present invention and means for mounting the ink jet head cartridge, and ejects ink from the ejection port of the recording head section based on a recording signal. The recording is performed by ejecting toward the recording medium.

[0016]

In the ink jet head cartridge of the present invention constructed as described above, the ink storage section, the supply section and the recording head section are filled with ink in the initial state. Further, at this time, the protrusion is in contact with one part of the partition wall, and the contact portion of the partition wall with the protrusion is initially deformed, but the slit of the partition wall is closed.

When recording is performed and ink in the recording head portion is consumed, the pressure on the recording head portion side of the partition wall becomes small, and the partition wall is dented toward the recording head portion side at the contact portion with the protrusion. Along with the dent of the partition wall, the slit of the partition wall is gradually opened, and the ink in the ink storage section is supplied to the recording head section side through the slit. When the ink of the ink storage unit side is supplied to the recording head unit side, the difference between the pressure of the recording head unit side and the pressure of the ink storage unit side gradually decreases,
The shape of the partition is restored and the slit is closed. Since the partition wall requires the largest force to generate the initial deformation, the partition wall may not be deformed due to the pressure change depending on the elasticity of the partition wall, and it may be difficult to supply the ink to the recording head unit side. Therefore, by preliminarily applying the initial deformation to the partition wall by the protrusion, the above operation is stably repeated along with the consumption of ink, and ink is supplied to the recording head unit as much as necessary.

[0018]

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

First, an embodiment of the ink jet head cartridge (hereinafter referred to as "cartridge") of the present invention will be described. FIG. 1 is a partially cutaway side view of an embodiment of a cartridge of the present invention. As shown in FIG. 1, the cartridge has a recording head section 2 for ejecting ink.
And an ink tank 3 as an ink storage tank for holding the ink to be supplied to the recording head unit 2 are integrated.

As shown in FIG. 2, the recording head unit 2 has a plurality of ejection openings 2b formed at a predetermined pitch on an ejection opening formation surface 2a facing a recording medium (not shown) at a predetermined interval. An electrothermal converter (e.g., a heating resistor) 2e for generating energy for ejecting ink along the wall surface of each liquid passage 2d that connects the common liquid chamber 2c and each ejection port 2b.
Is provided. The common liquid chamber 2c is provided in the supply unit 5 described later.
(See FIG. 1). Supply unit 5 to common liquid chamber 2
The ink supplied to c and temporarily stored invades into the liquid passage 2d due to a capillary phenomenon, forms a meniscus at the ejection port 2b, and keeps the state where the liquid passage 2d is filled. At this time, when the electrothermal converter 2e is energized via an electrode (not shown) to generate heat, the ink on the electrothermal converter 2e is rapidly heated to generate bubbles in the liquid passage 2d. The expansion causes the ink to be ejected from the ejection port 2b.

Here, the electrothermal converter 2e is shown as the energy generating element for generating energy, but the present invention is not limited to this, and a piezoelectric element for generating mechanical energy that momentarily applies the discharge pressure may be used. .

On the other hand, as shown in FIG. 1, the ink tank 3 supplies an ink bag 4 for holding the ink therein and the ink held in the ink bag 4 to the recording head portion 2 as necessary. And a supply unit 5 for. Ink bag 4
Is made of a flexible material in which polyethylene terephthalate is laminated on a polyethylene film, and the outside of the ink bag 4 has the same pressure as the atmospheric pressure due to an atmosphere communication port (not shown) formed on the outer wall of the ink tank 3. Therefore, as the ink in the ink bag 4 runs out, the ink bag 4 is crushed by the atmospheric pressure.

Next, the supply section 5 will be described in detail.
3 is an exploded perspective view of the supply unit 5 shown in FIG. 1, and FIG. 4 is a cross-sectional view of the supply unit shown in FIG. As shown in FIGS. 3 and 4, the cylindrical mounting base 6 is integrally provided with a cylindrical mounting base 6b having a smaller diameter than the mounting base 6 on one end surface thereof, and An ink flow path 6c is formed that connects the one end face side and the other end face side.

An open end of a hollow dome-shaped slit bladder 7 made of an elastic material is fitted and fixed to the outer peripheral surface of the mounting base 6b. A slit 7a is formed on the top of the slit bladder 7.
Is closed when the slit blade 7 is still fitted into the mounting base 6 (steady state), but is opened by the deformation of the slit blade 7. Ribs 7 extending from the brim portions 7b to the top of the slit blader 7 are provided on the outer walls of the slit blader 7 that face each other.
c and 7d are formed. The ribs 7c and 7d are preferably provided in a range of 35 ° to 90 ° with respect to the extension line of the slit 7a.

As the slit blader 7, silicone rubber, SBR, BR, IR, EPM, EPDM, butyl rubber, chloroprene rubber, urethane rubber, fluororubber,
Nitrile rubber, acrylic rubber, polysulfide rubber, ethylene rubber, fluorosilicone rubber, SEP rubber (silicone modified ethylene propylene rubber) and the like are preferably used, and the hardness thereof is preferably in the range of 15 to 70 °, and further 2
The range of 5 to 50 ° is more preferable. In addition, since these materials come into contact with the ink in the ink tank 3 (see FIG. 1), they do not have the property of changing the physical properties of the ink (surface tension, viscosity, etc.) or eluting into the ink. I won't. At the same time, it is necessary that the ink does not cause the physical properties of these materials to change.

A bladder cover 8 for covering the slit bladder 7 is fixed to the mounting base 6 by ultrasonic welding or heat welding. A protrusion 8b is formed on the inner wall of the bladder cover 8 so as to abut against the slit bladder 7, and the slit bladder 7 is initially deformed by the protrusion 8b. The formation position of the protrusion 8b is preferably in the range of 0 to 35 ° with respect to the longitudinal direction of the slit 7a. The reason is that when the slit blader 7 dents due to a differential pressure described later, the slit blader 7 dents at the contact portion with the protrusion 8b, so that the formation position of the protrusion 8b is outside the above range, This is because it is difficult for the slit 7a to open even if the slit bladder 7 is dented. In addition, the ink bag 4 is attached to the bladder cover 8.
An ink supply path 8a connected to the opening (see FIG. 1) is provided, and the ink in the ink bag 4 is supplied to the ink supply path 8a.
It is supplied to the slit blader 7 from a through the slit 7a, and is supplied to the recording head unit 2 (see FIG. 1).

Here, the ink used in the present invention will be described.

As the dye used in the ink, water-soluble acid dyes, neutral dyes, basic dyes and reactive dyes described in the color index can be used, and dyes not described in the color index can be used. However, any water-soluble dye can be used. The amount of the above dye used is not particularly limited, but is generally 0.1 to 20% by weight of the total weight of the ink.
Amounts which make up by weight, preferably 0.3 to 10% by weight, more preferably 0.5 to 6% by weight are suitable. And
The solvent used in the ink is water, or a mixed solvent of water and a water-soluble organic solvent, and particularly preferable is the mixed solvent, which is a polyhydric alcohol having an effect of preventing the ink from drying as the water-soluble organic solvent. It contains a class. The content of the water-soluble organic solvent is generally 2% of the total weight of the ink.
The range is -80 wt%, preferably 3-70 wt%, more preferably 4-40 wt%. As the water, deionized water is preferably used instead of general water containing various ions, and the content thereof is 35% by weight or more, preferably 45% by weight or more of the whole ink. In addition, the ink may contain an antifungal agent, a preservative, a pH adjusting agent, a viscosity adjusting agent, a surface tension adjusting agent, etc., if necessary.

Further, the viscosity of the ink at 25 ° C. is in the range of 1 to 20 cP, preferably 1 to 15 cP,
The surface tension is 30 dyne / cm or more, preferably 40
more than dyne / cm, and hydrogen ion concentration index (p
It is preferable that H) has physical properties of about 4 to 10.

Next, the operation of this embodiment will be described.

In the initial state (steady state) of the cartridge, as shown in FIG. 1, the slit 7a of the slit blader 7 is closed, and at this time, the discharge port 2b of the recording head unit 2 (see FIG. 2) is opened. The ink pressure is 30 mm or less. For this reason, in this state, the balance between the meniscus holding force at the ejection port 2b and the internal pressure of the ink tank 3 is maintained, so that ink may not easily leak from the ejection port 2b due to temperature change, atmospheric pressure change, vibration, or the like. Absent.
In this state, ink is ejected from the recording head unit 2 to perform recording, so that the ink inside the slit blader 7 is consumed. Along with this, the ink pressure inside the slit bladder 7 gradually decreases, the differential pressure from the ink pressure inside the ink bag 4 gradually increases, and the slit bladder 7
The part that is in contact with the protrusion 8b and is subjected to the initial deformation is crushed.

When the pressure difference between the inside of the slit bladder 7 and the ink bag 4 exceeds a certain value, the slit 7a of the slit bladder 7 is accompanied by the collapse of the slit bladder 7, as shown in FIG. The ink in the ink supply path 8a is supplied into the slit blader 7 through the slit 7a. When ink is supplied to the inside of the slit blader 7 in this way, the differential pressure between the inside of the slit blader 7 and the inside of the ink bag 4 gradually decreases.
The deformation of the slit blader 7 is gradually restored as the pressure difference between the inside of the slit blader 7 and the inside of the ink bag 4 decreases. When the deformation of the slit bladder 7 is restored to some extent,
The opened slit 7a is closed and kept in the initial state. As the recording progresses and the ink is consumed, the above operation is repeated and good ink supply is achieved.

Further, for the purpose of maintaining or improving the ink ejection state, the ejection port 2 is temporarily operated by a suction pump or the like.
Even when the ink is sucked from b, the inside of the slit bladder 7 and the ink bag 4 are the same as in the case of ink consumption during recording.
Since the pressure difference with the inside becomes large, the slit bladder 7 is dented and the slit 7a is opened, and ink is supplied from the ink bag 4 into the inside of the slit bladder 7. After the ink is supplied to the inside of the slit blade 7, the slit 7a is closed as the slit blade 7 is restored. Therefore, the pressure inside the slit bladder 7 is always in a range that does not affect the ejection.

On the other hand, the negative pressure generated in the recording head portion is 3
It is preferably in the range of 0 to 200 mm head. This is because when the negative pressure is 30 mm water head or more, ink leakage from the ejection port is likely to occur, and when the negative pressure is −200 mm water head or less, problems such as reduction of ink ejection volume and ink non-ejection are likely to occur. And more preferably 0
It is better to be in the range of ~ -150 mm head.

The factors that determine the negative pressure generated in the recording head portion are the thickness, the elastic modulus (rubber hardness) and the radius of the slit bladder 7. Therefore, the material and shape of the slit bladder are different from those of the recording head portion. It is necessary to select a suitable one so that the negative pressure is in the above range.

Further, when the above-described cartridge having the slit blader is mounted on the carriage of the serial type ink jet recording apparatus, since the internal volume of the slit blader is small, vibration of the slit blader due to movement of the carriage or the like may occur. The impact is not so great, but in order to further reduce the impact, it is desirable to minimize the ink volume in the bladder cover that also has an effect as a vibration preventing wall of the slit bladder. In addition, the ink around the slit bladder freezes in a low temperature environment, causing volume expansion, and as a result, the slit bladder is pressed against the frozen ink and prevents the ink inside the slit bladder from leaking from the ejection port. In order to do so, it is necessary that the ink volume in the bladder cover is small.

Next, another embodiment of the cartridge of the present invention will be described.

FIG. 6 is a partially cutaway side view of another embodiment of the cartridge of the present invention. As shown in FIG.
In the cartridge of this embodiment, the ink tank 13 is attachable to and detachable from the cartridge body 11 in which the recording head unit 12 and the supply unit 15 are integrated.
The ink tank 13 can be replaced when the ink of the above is exhausted.

The inside of the supply unit 15 of the cartridge body 11 is a sub-tank 20, and the sub-tank 20 is fitted into the mounting base of the mounting base 16 in the same manner as the embodiment of the cartridge shown in FIG. Slit blader 1
A dome-shaped portion lid cover 18 having an outer periphery of the slit blader 17 is fixed to the mount 16. A through hole is formed at the top of the bladder cover 18, and when the slit 17a of the slit bladder 17 is open, the ink in the sub tank 20 is supplied to the recording head unit 12 via the inside of the slit bladder 17. To be done. Since the recording head unit 12 may be the same as that shown in FIG. 1, the description thereof will be omitted. Sub tank 20
A cylindrical cartridge body side connecting portion 21 is integrally projectingly provided on the side wall of the cartridge body side connecting portion 21.
A stopper 21a extending in the radial direction toward the axial center portion of the cartridge body side connection portion 21 is formed at the tip of the cartridge main body side connection portion 21 over the entire circumference thereof.

An elastic member 22 having the same shape as the cross section of the hollow portion is provided in the hollow portion of the cartridge body side connecting portion 21 slidably in the axial direction of the hollow portion, and the elastic member 22 is also provided. A compression spring 23 is provided for urging the spring toward the stopper 21a, and the elastic member 22 seals the hollow portion. Further, the hollow portion of the cartridge main body side connection portion 21 communicates with the sub tank 20 through a communication hole 24 formed in the side wall of the sub tank 20. Therefore, the hollow portion of the cartridge main body side connection portion 21 is filled with the ink in the sub tank 20,
As described above, since the hollow portion of the cartridge main body side connection portion 21 is sealed by the elastic member 22, the ink in the sub tank 20 is not transferred to the cartridge main body side connection portion 21.
It never leaks. Further, in the hollow portion of the cartridge body side connection portion 21, the cartridge body side connection portion 21
A hollow needle-shaped connecting pipe 25 extending in the axial direction of the sub-tank 20 and having a tip end facing the elastic member 22 is provided so as to penetrate the side wall of the sub-tank 20.

On the other hand, the ink tank 13 has a cartridge body side guide portion 26 provided in the cartridge body 11.
Has an ink tank side guide portion 27 that is fitted to the cartridge body side guide portion 27.
6 and the ink tank 1 in the cartridge body 11
When the ink cartridge 3 is mounted, an ink tank side connecting portion 28, which is a recess into which the cartridge main body side connecting portion 21 can be inserted, is provided at a portion of the ink tank 13 that faces the cartridge main body side connecting portion 21. Ink tank side connection 2
An opening communicating with the inside of the ink tank 13 is formed in the bottom portion of the ink container 8, and the opening is closed by a lid member 29 made of the same material as the elastic member 22. This lid member 2
The cross section of 9 has the same shape as the cross section of the opening of the cartridge body side connection portion 21 surrounded by the stopper 21a.
When the ink tank 13 is attached to the cartridge body 11, the lid member 29 slides the elastic member 22 leftward in the drawing against the spring force of the compression spring 23. At this time, the connecting tube 25 sequentially penetrates the elastic member 22 and the lid member 29, and the tip of the connecting tube 25 reaches the inside of the ink tank 13.

Further, an ink tank inner bag 30 made of a flexible material is provided inside the ink tank 13, and one end of the ink tank inner bag 30 has an atmosphere communication port 31.
It communicates with the outside through. Ink tank inner bag 30
Is compressed and stored in the ink tank 13 in the initial state (a state in which the ink tank 13 is filled with ink), and the ink in the ink tank 13 is consumed by the ejection of ink from the recording head unit 12. , Atmosphere communication port 3
Air is introduced into the ink tank inner bag 30 via 1 and gradually inflates, and the pressure in the ink tank 13 is maintained substantially constant.

Next, the operation of this embodiment will be described.

First, when the ink tank side guide portion 27 is fitted into the cartridge body side guide portion 26 and the ink tank 13 is inserted along the cartridge body side guide portion 26, the cartridge body is connected to the ink tank side connecting portion 28. The side connecting portion 21 is fitted to the elastic member 22 and the lid member 29.
And abut. When the ink tank 13 is further inserted, the lid member 29 pushes the elastic member 22 against the spring force of the compression spring 23, and the connecting tube 25 sequentially penetrates the elastic member 22 and the lid member 29. When the ink tank 13 is completely attached to the cartridge body 11, the tip of the connecting pipe 25 reaches the inside of the ink tank 13, and
The inside of the ink tank 13 and the inside of the sub-tank 20 communicate with each other via 5. The inside of the cartridge main body side connection portion 21 is filled with ink, and the connecting pipe 25 penetrates the elastic member 22 and the lid member 29, and the sub tank 20.
And the ink tank 13 are communicated with each other, so that the connecting tube 25
Does not come into contact with air both when the ink tank 13 is not attached and when it is attached, and clogging due to drying of the ink in the connecting tube 25 does not occur.

The ink tank 13 is attached to the cartridge body 11.
Recording is possible when is completely attached. The operation at the time of recording is similar to that of the cartridge shown in FIG.

In the cartridge of this embodiment, an example in which the supply section 15 and the ink tank 13 are separated is shown, but the separated section is not limited to this, and the recording head section 12 is not limited to this.
The supply unit 15 and the supply unit 15 may be separable.

Next, an embodiment of the ink jet recording apparatus will be described.

In FIG. 7, the cartridge 101 integrally provided with a recording head section for ejecting ink based on a predetermined recording signal to record a desired image is the same as that shown in the embodiment of the cartridge. It has a similar configuration.

The carriage 102, on which the cartridge 101 is mounted, is slidably fitted in the two guide shafts 103 and 104 in the direction of the arrow B, and is rotatable with the pulley 107 fixed to the output shaft of the carriage motor 105. Timing belt 108 wound around the supported pulley 106
Is bound to one site. The cartridge 101 has a structure in which the pulley 107 rotates in the forward direction and the reverse direction by the driving force of the carriage motor 105, so that the timing belt 108 rotates in the forward direction and the reverse direction, and reciprocates in the arrow B direction.

The recording paper 109, which is a recording medium, is guided by a paper pan 110 and is conveyed by a paper feed roller (not shown) which is pressed against by a pinch roller. This conveyance is performed using the paper feed motor 116 as a drive source. The conveyed recording paper 109 is ejected by the paper ejection roller 11
Tension is added by 3 and spur 114,
The paper holding plate 112 formed of an elastic member causes the heater 1 to
Since it is pressed against 11, it is conveyed while being in close contact with the heater 111. Recording paper 109 to which ink ejected from the recording head portion of the cartridge 101 adheres
Is heated by the heater 111, and the water content of the attached ink evaporates and is fixed on the recording paper 109.

The recovery unit 115 is for maintaining the ejection characteristics in a normal state by removing foreign matters and ink of high viscosity adhering to the ejection ports (not shown) of the recording head section.

The recovery unit 115 has a cap 11
8a is provided to prevent the occurrence of clogging by capping the ejection port of the recording head unit. An ink absorber 118 is arranged inside the cap 118a.

In addition, the recovery unit 115 has a recording area side in contact with the surface of the recording head portion on which the ejection openings are formed to clean foreign matters and ink droplets attached to the surface on which the ejection openings are formed. Cleaning blade 11
7 is provided.

In each of the embodiments described above, the cartridge and the ink jet recording apparatus are of the serial type, but the present invention can be applied to the full line type.

The present invention is particularly equipped with means for generating thermal energy as energy used for ejecting ink in the ink jet recording system (for example, an electrothermal converter or laser light), and the ink is generated by the thermal energy. In the recording head and the inkjet recording apparatus of the type that causes the change of the state (1), the effect is excellent.

Regarding its typical structure and principle, see, for example, US Pat. Nos. 4,723,129 and 4740.
No. 796, the present invention is preferably carried out using these basic principles. This recording method is applicable to both the so-called on-demand type and the continuous type.

This recording method will be briefly described. A sheet (liquid) holding a liquid (ink) or an electrothermal converter arranged corresponding to a liquid path is changed to a liquid (ink) corresponding to recording information. Thermal energy is generated by applying at least one drive signal for giving a rapid temperature rise that causes the film boiling phenomenon beyond the nucleate boiling phenomenon, and causes the film boiling on the heat acting surface of the recording head. . In this way, bubbles can be formed in one-to-one correspondence with the drive signal applied from the liquid (ink) to the electrothermal converter, which is particularly effective for the on-demand recording method. By the growth and contraction of the bubbles, liquid (ink) is ejected through the ejection holes,
Form at least one drop. It is more preferable to make the driving signal into a pulse shape because bubbles can be grown and contracted immediately and appropriately, and thus a liquid (ink) with excellent responsiveness can be ejected. As the pulse-shaped drive signal, U.S. Pat. Nos. 4,463,359 and 4,345 are used.
Those as described in the '262 patent are suitable. If the conditions described in US Pat. No. 4,313,124, which is an invention relating to the rate of temperature rise on the heat acting surface, are adopted, more excellent recording can be performed.

The structure of the recording head is a combination of a discharge hole, a liquid flow path, and an electrothermal converter as disclosed in the above-mentioned specifications (straight liquid flow path or right-angled liquid flow path).
In addition, as disclosed in U.S. Pat. No. 4,558,333 and U.S. Pat. No. 4,459,600, the present invention includes those having a configuration in which a heat acting portion is arranged in a bending region.

In addition, Japanese Laid-Open Patent Publication No. 123670/1984, which discloses a structure in which a common slit is used as a discharge hole for a plurality of electrothermal converters, absorbs a pressure wave of thermal energy. The present invention is also effective in a structure based on Japanese Patent Laid-Open No. 138461/1984, which discloses a structure in which the corresponding opening corresponds to the discharge portion.

Further, as a full line type recording head having a length corresponding to the maximum width of the recording medium which can be recorded by the recording apparatus, a full line type recording head is disclosed by combining a plurality of recording heads as disclosed in the above specification. It may be one having a line structure or one full line recording head integrally formed.

In addition, by being attached to the apparatus main body, it can be electrically connected to the apparatus main body and can be supplied with ink from the apparatus main body by a replaceable chip type recording head or the recording head itself. The present invention is also effective when a cartridge-type recording head that is specially provided is used.

Further, it is preferable to add recovery means for the recording head, preliminary auxiliary means, etc. to the recording apparatus of the present invention because the recording apparatus of the present invention can be made more stable. Specifically, the recording head is preheated by a capping means, a cleaning means, a pressure or suction means, an electrothermal converter or a heating element other than this, or a combination thereof. It is also effective to perform stable recording by adding a means for performing a preliminary ejection mode for performing ejection different from the means and recording.

Further, the recording mode of the recording apparatus is not limited to the mode in which only the mainstream color such as black is recorded, and either the recording head may be integrally formed or a plurality of recording heads may be combined. However, the present invention is extremely effective for an apparatus provided with at least one of a multicolor of different colors or a full color by color mixing.

In the embodiments of the present invention described above, the liquid ink is used for explanation. However, in the present invention, either an ink which is solid at room temperature or an ink which is in a softened state at room temperature is used. Can be used. In the above-mentioned inkjet device, the temperature of the ink itself is generally adjusted within the range of 30 ° C. or higher and 70 ° C. or lower to control the temperature of the ink so that the viscosity of the ink is within the stable ejection range. Any liquid may be used as long as the ink is liquid.

In addition, the excessive temperature rise of the head or ink due to thermal energy is positively prevented by using it as the energy for the state change of the ink from the solid state to the liquid state, or the evaporation of the ink is prevented. It is also possible to use an ink that solidifies when left as it is. In any case, liquefaction occurs only when heat energy is applied, such as when the ink is liquefied by applying heat energy according to the recording signal and ejected as an ink liquid, or when it begins to solidify when it reaches the recording medium. The use of an ink having such a property is also applicable to the present invention.

Such an ink is disclosed in JP-A-54-568.
No. 47 or Japanese Patent Laid-Open No. 60-71260, facing the electrothermal converter in the state of being held as a liquid or solid in the recesses or through holes of the porous sheet. It may be in the form.

In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

[0068]

Since the present invention is configured as described above, it has the following effects.

By providing the supply portion with the partition wall having the slit, the slit is opened only when a predetermined pressure difference is generated between the ink storage portion and the outside. It is possible to reliably supply the ink inside the unit to the outside (recording head unit) when necessary. In addition, the protrusion is brought into contact with one part of the partition wall and the partition wall is initially deformed, so that the partition wall is likely to be dented when a differential pressure is generated between the ink storage portion and the outside (recording head portion), Since the ink pressure of the outside (recording head portion) is kept within a certain range, the ink can be more stably supplied to the outside (recording head portion).

Further, by providing a cover member for covering the partition wall, when mounted on a serial type ink jet recording apparatus, vibration of the partition wall due to movement of the carriage is suppressed, and unnecessary pressure fluctuation of ink is suppressed. ,
A more stable ink supply becomes possible.

In addition, the protrusion can be brought into contact with a part of the partition wall in the range of 0 to 35 ° with respect to the longitudinal direction of the slit, whereby the slit can be surely opened by the recess of the partition wall.

[Brief description of drawings]

FIG. 1 is a partially cutaway side view of an embodiment of an inkjet head cartridge of the present invention.

FIG. 2 is a perspective view of a main part of the recording head unit shown in FIG.

FIG. 3 is an exploded perspective view of the supply unit shown in FIG.

FIG. 4 is a cross-sectional view showing a state in which the slits of the supply unit shown in FIG. 1 are closed.

5 is a cross-sectional view showing a state where the slits of the supply unit shown in FIG. 1 are opened.

FIG. 6 is a partially cutaway side view of another embodiment of the inkjet head cartridge of the present invention.

FIG. 7 is a schematic perspective view of an embodiment of the inkjet recording apparatus of the present invention.

[Explanation of symbols]

 2, 12 recording head part 2a ejection port surface 2b ejection port 2c common liquid chamber 2d liquid path 2e electrothermal converter 3, 13 ink tank 4 ink bag 5, 15 supply part 6, 16 mounting base 6b mounting base 6c ink flow path 7, 17 Slit bladder 7a, 17a Slit 7c, 7d Rib 8, 18 Bladder cover 8a Ink supply path 11 Cartridge body 20 Sub-tank 21 Cartridge body side connection part 21a Stopper 22 Elastic member 23 Compression spring 24 Communication hole 25 Connection tube 26 Cartridge body Side guide part 27 Ink tank side guide part 28 Ink tank side connection part 29 Lid member 30 Ink tank inner bag 31 Atmosphere communication port 101 Cartridge 102 Carriage 103, 104 Guide shaft 105 Carriage motor 106, 107 Pulley 108 Timing belt Lt 109 recording paper 110 paper pan 111 heater 112 paper retainer plate 113 discharge roller 114 spur 115 recovery unit 116 paper feed motor 117 cleaning blade 118 absorber 118a cap

 ─────────────────────────────────────────────────── ─── Continued Front Page (72) Inventor Masami Kojima 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (8)

[Claims] 1. An ink storage tank having an ink storage unit for holding ink inside, and a supply unit for supplying the ink held in the ink storage unit to the outside as necessary. The part is closed in a steady state, and a partition wall made of an elastic member having a slit formed to open when a predetermined differential pressure is generated between the ink storage part and the outside, and a peripheral part of the partition wall are attached. An ink storage tank, comprising: a base member in which an ink flow path is formed; and a protrusion that abuts on one part of the partition wall and gives an initial deformation to the one part of the partition wall. 2. The ink storage tank according to claim 1, wherein the supply unit is provided with a cover member that covers the partition wall, and the protrusion is provided on the cover member. 3. The ink storage tank according to claim 1, wherein the partition has a hollow dome shape in which at least a top portion has a hemispherical shape, and a slit is formed in the top portion. 4. The ink storage tank according to claim 1, 2 or 3, wherein the protrusion is in contact with a part of the partition wall in the range of 0 to 35 ° with respect to the longitudinal direction of the slit. 5. An ink jet head cartridge having the ink storage tank according to claim 1 and a recording head unit connected to the ink storage tank for ejecting ink from an ejection port. 6. The ink jet head cartridge according to claim 5, wherein the recording head portion is a full line type in which ejection openings are formed over the entire width of the recording area of the recording medium. 7. The recording head unit discharges ink by utilizing thermal energy and has an electrothermal converter as an energy generating element for generating the thermal energy. Inkjet head cartridge. 8. An inkjet head cartridge according to any one of claims 5 to 7, and a means for mounting the inkjet head cartridge,
An inkjet recording apparatus that performs recording by ejecting ink toward a recording medium from an ejection port of the recording head unit based on a recording signal.