JP2840513B2 - Ink tank and inkjet recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus for supplying ink to a recording head and performing recording on a recording medium, an ink tank used in the apparatus, a recording head with an ink tank, and a method for detecting the remaining ink amount.

[0002]

2. Description of the Related Art An ink tank used in an ink jet recording apparatus includes:
It is required that ink suitable for the amount of ink ejected from the recording head can be satisfactorily supplied at the time of recording, and that there is no leakage of ink from the ejection ports during non-recording.

If the ink tank is of a replaceable type, it is required that the ink tank be smoothly attached and detached without any ink leakage at that time, and that the ink be reliably supplied to the recording head.

[0004] As a conventional ink tank for an ink jet recording apparatus, first, an ink bag filled with ink is mounted below a recording head position, and ink is supplied to the recording head by drawing an ink supply tube. There is a method. In this method, a negative head pressure is generated due to a difference in height between the tank and the recording head, and a stable ink meniscus is maintained at the ink discharge port.
However, not only is the supply system itself very large and it is difficult to reduce the size of the device, but also as the ink evaporates through the plastic tube, the thickened ink is discharged from the discharge port using a recovery pump. There has been a problem of waste ink treatment and an increase in running cost, such as necessity and an increase in ink consumption.

Another example of an ink tank used in a conventional ink jet recording apparatus is disclosed in JP-A-63-632.
No. 42 discloses this. This is an ink jet recording cartridge having a plurality of ink ejection orifices in which a foaming agent (absorber) is arranged in an ink tank. In order to maintain a stable ink meniscus in the ink ejection section of the recording head, the ink is used. The tank is filled with an absorbent such as polyurethane foam as a foam material, and the ink is held by the capillary force of the absorbent. In this case, an absorber is required for almost the entire inside of the ink tank, and an internal negative pressure is generated by holding ink slightly smaller than the maximum amount of ink that can be held by the absorber. Even when a mechanical shock such as vibration or a thermal shock such as a temperature change is applied to the tank, there is no leakage of ink from the discharge section of the recording head or the air communication section of the ink tank.

However, in the conventional system in which the absorber is completely filled in the tank, the amount of ink that can be held (ink holding ratio) with respect to the volume of the ink tank is small, and the amount of ink that is not used increases, and the usage efficiency increases. There was a problem of bad. In addition, considering that the ink tank scans the recording paper facing the recording paper together with the recording head, there has been a problem in reducing the size of the main body of the recording apparatus and reducing the running cost.

[0007] Therefore, it is desired to use ink having a high use efficiency, and a method using no absorber in the ink tank has been proposed.

For example, a system using an ink bag urged by a spring in an ink tank has been devised. Although this spring bag method is excellent in that the internal negative pressure in the ink supply unit is stably generated by using a spring force, there are restrictions on a spring shape for obtaining a predetermined internal negative pressure and an ink tank. However, there is a problem that the process of fixing the bag is slightly complicated, the manufacturing cost is high, and the ink holding ratio is small in a thin ink tank.

Although not known at the time of filing the present application, the present inventors have devised a type in which the absorber is not completely filled in the ink tank but is partially filled. This improves the ink use efficiency by improving the ink holding ratio by providing a portion not filled with the porous member. That is, a supply unit ink chamber that includes an ink supply unit to the recording head and an air communication unit and contains an ink absorber with adjusted capillary force, and one or more ink chambers that communicate with it and store ink. An ink tank cartridge comprising:

However, in this ink tank cartridge, if the ink in the supply unit ink chamber containing the ink absorber is used up, the ink is supplied to the recording head properly even if the ink is refilled (refilled). May not be.

FIG. 17 shows a state in which ink is refilled from a state in which the ink in the supply section ink chamber is completely used.

Even if the ink in the ink chamber of the supply section (ink chamber a described later) is used up, a small amount of ink actually remains inside the absorber and forms a meniscus everywhere in the absorber. I have. In this state, even if ink is refilled in the ink chamber b that does not contain the absorber, a meniscus has already been formed everywhere in the absorber in the ink chamber a. It cannot be filled densely without gaps, and large bubbles are interposed in some places. Even if the recording head is joined to the recording head in this state, since a considerable amount of air bubbles are present in the absorber in the ink chamber a, the ink flow is poor and the ink is easily interrupted, and the ink is not supplied to the recording head properly. .

SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and provides an ink tank, a recording head with an ink tank, and a method for detecting the remaining amount of ink, which can refill ink and can be reused. With the goal.

According to another aspect of the present invention, there is provided an ink supply chamber containing an ink absorber, an ink supply chamber containing an ink absorber, and an ink supply chamber for communicating with the ink supply chamber. And an ink detecting means for detecting a decrease in the remaining amount of ink when a predetermined amount of ink remains in the ink chamber.

Further, according to the present invention, there is provided a recording head with an ink tank, wherein a recording head is connected to an ink supply section of the ink tank.

Further, according to the present invention, there is provided an ink jet recording apparatus for performing recording using the recording head provided with the ink tank, wherein the ink functions together with an ink detecting means provided in the ink tank, and ink is contained in the ink chamber. It is characterized by comprising: an ink remaining amount detecting unit that detects a decrease in the remaining amount of ink when a predetermined amount remains, and an informing unit that notifies the remaining amount of ink based on a detection result of the ink remaining amount detecting unit. An inkjet recording device is provided.

Further, according to the present invention, there is provided a method for detecting the remaining amount of ink in the ink tank, the method comprising: detecting a decrease in the remaining amount of ink when a predetermined amount of ink remains in the ink chamber; A method for detecting the remaining amount of ink in an ink tank is provided.

Further, according to the present invention, there is provided the ink refilling method of the ink tank, wherein a decrease in the remaining amount of the ink is detected when a predetermined amount of the ink remains in the ink chamber. A method for refilling ink in an ink tank, comprising refilling ink.

[0019]

An ink supply chamber having an ink supply section to the recording head and an atmosphere communication section and containing an ink absorber, and at least one ink chamber communicating with the ink supply chamber and containing ink are formed. When a predetermined amount of ink remains in the ink chamber of the provided ink tank, a decrease in the remaining amount of ink is detected, and the detection result is reported.

Thus, the recording operation is stopped, and the ink can be refilled (refilled) into the ink chamber.

According to the present invention, there is provided an ink tank having a high ink holding ratio, capable of refilling, maintaining stable ink ejection, and reliably preventing ink from leaking due to a change in use environment conditions. . Further, since the ink tank can be refilled, the ink tank can be reused, which is excellent in economy and can reduce the amount of waste.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Embodiments of the present invention will be described in detail with reference to the drawings.

<First Embodiment> FIG. 1 is a schematic perspective view showing a part of an ink tank according to a first embodiment of the present invention.
FIG. 2 is a schematic sectional view of the first embodiment.

As shown in FIGS. 1 and 2, the ink tank 1 of this embodiment partitions the interior into two ink chambers (a, b) and communicates at the bottom, and adjusts the capillary force to one of the ink chambers a. An ink supply unit 2 for filling the ink absorber 7 and connecting to the ink jet recording head, an air communication unit 3, a residual detection pin (electrode) 4, and an ink inlet 5 are provided. . The ink inlet 5 is closed with a stopper 51 made of rubber or the like.

The positional relationship among the atmosphere communication unit 3, the ink supply unit 2, the residual detection pin (electrode) 4, and the ink injection port 5 is not particularly limited to this.

As the ink absorber 7 used in the present invention, a conventionally known member can be used as long as it has the ability to hold the ink against its own weight and slight vibration of the liquid (ink). In an ink jet recording apparatus, a heater may be damaged by a substance eluted from a member, and there are some restrictions on material selection. In consideration of these, a sponge such as a polyurethane foam which can easily adjust the ink holding power and the negative pressure generation is preferable. In particular, a foam is preferable because it can be adjusted to a desired porosity during foam production.

FIG. 2 is a cross-sectional view showing a state in which the recording head, ink tank, and carriage of the ink jet recording apparatus of the present invention are connected. The recording head 10 in this embodiment is of an ink jet type that performs recording using an electrothermal transducer that generates thermal energy for causing film boiling to occur in ink in response to an electric signal. In FIG. 2, all of the main components of the recording head 10 are stacked or laminated on the head base plate 11 by using the positioning projections 100 provided on the head base plate 11 as a positioning reference. Here, the in-plane vertical direction in FIG. 2 is positioned by the head positioning portion 104 and the protrusion 100 of the carriage HC.

The vertical direction of the cross-sectional view of FIG.
A portion of the protrusion 100 projects so as to cover the head positioning portion 104, and is positioned by the notch portion (not shown) of the projection 100 and the head positioning portion 104. The heater board 13 includes a plurality of electrothermal transducers (discharge heaters) arranged in a plurality of rows on an Si substrate, and electrical wiring made of Al or the like for supplying power thereto, formed by a film forming technique. Each of the wirings is connected by wire bonding to a head flexible substrate (hereinafter, referred to as a “head PCB”) having a wiring in which a pad for receiving an electric signal from the device is disposed at an end. Forming a common liquid chamber and a plurality of discharge ports for introducing ink from the replacement ink tank 1 and supplying the ink to the ink flow path through partition walls and flow paths for partitioning the plurality of ink flow paths corresponding to the discharge heaters; Top plate 1 in which the orifice to be molded is integrally molded with polysulfone etc.
2 is pressed against the heater board 13 by a spring (not shown), and is press-fixed and sealed using a sealant to form an ink discharge portion.

The flow path forming portion 1 joined and sealed to the groove top plate 12
In this embodiment, 5 is penetrated to the opposite side of the head base plate 11 through a hole provided in the head PCB and the head base plate 11 so that the head base plate 11 can be connected to the replacement ink tank 1. Adhesively fixed. In addition, the flow path forming section 15
A filter 8 for preventing inflow of dust and air bubbles into the ejection section is provided at an end on the side connected to the ink tank 1.

The replacement ink tank 1 is connected to the recording head 10 by the engagement guide 6 and the pressurizing means 103, and the ink absorber 7 is provided with a filter 8 provided at the tip of the flow path forming portion 15.
, Ink communication becomes possible. At this time, the pad 14 is also provided on the pressurizing means 103 to electrically connect the residual detection electrode 4 of the tank to the main body of the recording apparatus.

After the connection, the ink is supplied by forcibly supplying and filling the recording head 10 with the ink from the replacement ink tank 1 using the recording head suction recovery pump 5015 of the recording apparatus main body.

In this embodiment, the recording head 10 and the replacement ink tank 1 are connected when the pressing means 103 is engaged, and the recording head 10 and the carriage H are moved in the same direction.
Since C and C are mechanically and electrically connected, the positioning between the pad 14 on the head PCB and the head drive electrode 102 is also ensured.

In the present embodiment, the ring seal 9 is formed of a somewhat thick elastic ring so as to allow the so-called play in the ink supply section 2 and to make the joint portion with the outer wall of the replacement ink tank wider.

As described above, in this embodiment, the carriage H is urged by sufficiently coupling the replacement ink tank 1 and the recording head 10 and then urging the replacement ink tank 1.
C and the recording head 10 are reliably positioned with a simple configuration, and the recording head 10 and the replacement ink tank 1 are easily connected outside the main body and then mounted on the carriage. We were able to. Also,
In this embodiment, since the electrical connection between the carriage HC (printing apparatus main body) and the printhead 10 is also made in the same manner, the operability at the time of replacement of the printhead and the replacement ink tank is good. Alternatively, a configuration may be adopted in which the connection of the recording head and the connection with the replacement ink tank are made more reliable by using a separate connector connection method or the like.

Here, in order to explain the arrangement and operation of the recording head in the ink jet recording apparatus according to the present embodiment, the operation of the recording apparatus will be briefly described with reference to FIG. 3 which is a perspective view. In FIG. 3, the recording medium P is guided upward from the bottom of the sheet using a platen roller 5000, and the platen
000.

The carriage HC has a lead screw 5005 which operates as a driving source by inserting a carriage driving pin into its spiral groove 5004 and rotating itself.
And a slider 5003 arranged in parallel with the lead screw 5005 and supported by a platen roller 5000.
It reciprocates left and right along the recording surface of the recording medium P guided upward. The lead screw 5005 is connected to the drive transmission gear 50.
11 and 5009, the rotational drive is controlled in conjunction with the forward / reverse rotation of the drive motor 5013. Reference numerals 5007 and 5008 denote home position detection means for confirming the presence of the lever 5006 of the carriage HC in this area by photocouplers and switching the rotation direction of the motor 5013.

The image recording signal is sent to the recording head 10 by timing the movement of the carriage HC on which the recording head is mounted.
The recording head 10 ejects ink droplets at predetermined positions to perform recording. Reference numeral 5016 denotes a member that supports a cap member 5022 that caps the front surface of the recording head 10,
Reference numeral 5015 denotes suction means for suctioning the inside of the cap, and performs suction recovery of the recording head via the opening 5023 in the cap. Reference numeral 5017 denotes a cleaning blade. Reference numeral 5019 denotes a member that allows the blade to move in the front-rear direction. These members are supported by a main body support plate 5018. The suction unit 5015, the blade 5017, and the like need not be in this form, and well-known ones can be applied. Also, 5012
Is a lever for determining the timing of the suction recovery operation, moves with the movement of the cam 5020 engaging with the carriage, and the driving force from the driving motor 5013 is controlled to move by known transmission means such as clutch switching. . These recovery means are configured such that when the carriage HC comes to the home position side area, desired processing can be performed at predetermined positions at the corresponding positions by the action of the lead screw 5005.

Hereinafter, the present invention will be described in more detail.

The state of the ink in FIG. 4 shows an initial state in which the ink chambers a and b are sufficiently filled. FIG. 5 shows the ink that can be supplied to the ink chamber a and １ ／ of the ink chamber b from the initial state.
This is a state in which about ink has been consumed.

In order to maintain the negative pressure immediately after opening the ink cartridge, the ink chamber b may be filled up to the volume limit, but the ink filling amount in the ink chamber a is not more than the ink holding force limit of the absorber. It is preferable that the setting be made, and within this range, most of the ink chamber a can be filled with ink as shown in FIG. Here, the ink holding power refers to the ability of the absorbing member to hold the ink alone when the ink is impregnated into the absorbing member.

In FIG. 5, the ink of the compressed ink absorber is maintained at a height where the water head pressure from the ejection portion of the recording head, the pressure reduction in the ink chamber b, and the capillary force in the compressed ink absorber are balanced. . When the ink is supplied from the ink supply unit 2, the amount of ink in the ink chamber a does not decrease and the ink chamber b
Of ink is consumed. That is, while the ink distribution in the ink chamber a does not change and the balance of the internal pressure is maintained, the ink corresponding to the ink supply is consumed in the ink chamber b and the corresponding air is communicated with the atmosphere through the ink chamber a. Introduced from part 3.

At this time, the ink and the atmosphere are exchanged in the communicating portion between the ink chamber a and the ink chamber b, and the meniscus formed on the compressed ink absorber of the ink chamber a is partially broken from the portion adjacent to the ink chamber b. Then, the air is introduced into the ink chamber b so that the pressure in the ink chamber b is balanced with the meniscus holding force of the compressed ink absorber. That is, the internal pressure of the ink supply unit 2 is maintained at a predetermined value by the capillary force of the compressed ink absorber in the ink chamber a. At this time, as shown in FIG. 6, by providing a slit 7 or the like between the ink chamber wall and the compressed ink absorber in the ink chamber a, the air from the air communication portion can easily pass and the ink in the ink chamber a can be retained. It is effective in terms of.

Next, detection of the remaining amount of ink will be described.

FIG. 7 shows an example of the configuration of a control system according to this embodiment. Reference numeral 200 denotes a microcomputer-type control unit having a built-in A / D converter, 10 denotes a recording head unit, 300 denotes a voltage conversion circuit, and 400 denotes an alarm device. Can be combined. Reference numeral 500 denotes a main scanning mechanism for scanning the carriage HC during printing or the like, and includes a motor and the like. 600 is a sub-scanning mechanism,
It includes a motor for transporting the recording medium and the like. Also, V
Is a remaining amount detection signal from the tank.

In this embodiment, basically, a constant current is passed between two electrodes provided in the ink chamber b to detect the remaining amount of ink in the ink chamber b based on the resistance value between the two electrodes. In this case, the relationship between the remaining amount of ink and the resistance between the electrodes has a relationship as shown in FIG.

As shown in FIG. 9, when the ink level in the ink chamber b drops below the upper one of the two electrodes 4, the resistance between the two electrodes sharply increases and the gap between the electrodes at that time increases. Voltage is generated. This voltage is A / D converted by the A / D converter of the control unit directly or via the voltage conversion circuit 300. The detection value thus obtained is set to a predetermined value Rt.
When it becomes larger than h, the alarm device 400 for informing the operator that the ink injection time has come is activated. At this time, the operation of the main body may be stopped at the same time,
It may be stopped after the printing operation is completed.

Accordingly, if it is awaiting that the ink is refilled with a small amount of ink remaining in the ink chamber b, the ink in the ink chamber a containing the absorber is refilled without interruption, so that the tank is refilled. Reuse becomes possible.

FIG. 10 shows how the internal pressure in the ink supply section of the replacement ink tank of this embodiment changes according to the ink supply amount (consumption amount). In the initial state, the internal pressure (negative pressure) is generated due to the capillary force of the compressed ink absorber in the ink chamber a. However, as the amount of ink in the ink chamber a decreases with the supply of ink, the compression ratio distribution of the compressed ink absorber is reduced. The internal pressure generated by the capillary force gradually increases according to the (pore distribution). When the ink is further consumed, the ink distribution in the ink chamber a is stabilized, the ink in the ink chamber b is consumed, and the atmosphere is introduced into the ink chamber b as described above, and thereafter, the ink is substantially constant. To maintain the internal pressure. When the ink is further consumed and a predetermined amount of the ink in the ink chamber b is consumed, the remaining ink amount detection is activated, and an operation for prompting an ink refill and stopping the printing are performed. As a result, the ink in the ink chamber a can be refilled before the predetermined amount or more of the ink is consumed, and the ink can be maintained in a reusable state.

As an example of the refilling method, as shown in FIG. 11, the stopper 51 of the ink inlet 5 of the ink chamber b is opened, and the ink is injected into the ink chamber b using a syringe 52 or the like. The inlet 5 may be closed with the stopper 51. The refill method is not particularly limited to this, and the position of the ink injection port 5 is not limited to this. As a result, the ink tank cartridge can be used many times without being disposable.

In the present embodiment, the method for detecting the remaining amount of ink has been described as a method for detecting from the resistance value between the electrodes provided in the tank, but the method for detecting the remaining amount is not particularly limited. Any method such as a method of optically measuring or a method of optically measuring may be used.

FIG. 12 illustrates the function of the compression absorber as a buffer absorber. In the state shown in FIG. 5, the ink chamber b is expanded due to the expansion of the air in the ink chamber b due to a decrease in atmospheric pressure or an increase in temperature. Of the ink has flowed out toward the ink chamber a. In this embodiment, the ink flowing out into the ink chamber a is held by the compression absorber.
Regarding the relationship between the ink absorption amount of the compression absorber and the ink chamber, from the viewpoint of preventing the ink leakage at the time of the above-described pressure reduction or temperature change, the amount of the ink flowing out from the ink chamber b under the worst condition, Considering the amount of ink held in the ink chamber a when the ink is supplied from the chamber b, the ink chamber a
The maximum amount of ink absorption may be determined, and the ink chamber a may have at least a volume for accommodating the corresponding compression absorber. FIG. 13 shows the initial space volume of the ink chamber b before decompression and the value of 0.1.
The relationship with the ink outflow amount when the pressure was reduced to 7 atm is shown in the solid line graph. In addition, the case where the maximum decompression condition of the atmospheric pressure is set to 0.5 atm is shown by a dashed line in FIG. Ink chamber b
In the worst condition of the amount of ink flowing out of the ink chamber b, for example, when the maximum pressure reducing condition of the atmospheric pressure is set to 0.7 atm, the amount of ink flowing out from the ink chamber b becomes the maximum due to the volume VB of the ink chamber b. In this case, 30% of the ink remains in the ink chamber b. If the ink below the lower end of the ink chamber wall is also absorbed by the compression absorber of the ink chamber a, the remaining ink remains in the ink chamber b. It can be considered that all the ink (30% of VB) leaks. When the worst condition of the atmospheric pressure is 0.5 atm, 50% of the ink in the ink chamber b flows out. In other words, the air in the ink chamber b that expands under reduced pressure becomes larger as the remaining ink amount is smaller, and a larger amount of ink is pushed out, but does not flow out more than the ink amount in the ink chamber b. Therefore, assuming a pressure of 0.7 atm, if the remaining ink becomes 30% or less, the amount of the remaining ink becomes smaller than the amount of expansion of the air, so that the amount of ink flowing out into the ink chamber a decreases, and 30% of the volume (50% at 0.5 atm) is the maximum leaked ink amount. The above phenomenon is the same even when the temperature of the ink tank changes, but even when the temperature rises by about 50 deg, the outflow amount is smaller than that at the time of the above-described pressure reduction.

In the present embodiment, a single-color recording apparatus having one recording head has been described. However, a plurality of recording heads capable of ejecting inks of different colors, for example, Bk (black) · C
The present invention is applicable to a color ink jet recording apparatus having four heads of (cyan), M (magenta), and Y (yellow), and also applicable to a recording head capable of discharging a plurality of colors of ink with one recording head. In this case, means for regulating the coupling position and direction of the exchange tank may be added.

In this embodiment, an example in which the ink tank is replaced has been described. However, a print head with an ink tank integrally formed with a print head and an ink tank filled with a predetermined amount of ink is provided. It is also possible to apply to the tank integral exchange system.

<Second Embodiment> FIGS. 14 to 16 show modified examples of the present embodiment, in which two ink chambers c and d are provided in communication with an ink chamber b. In this modification, ink is consumed in the order of the ink chamber b, the ink chamber c, and the ink chamber d. The reason why the ink chamber is divided into four in this modified example is to prevent the ink from leaking under the reduced pressure environment and the temperature change described in the above embodiment.
When the atmosphere in the ink chamber b and the ink chamber c expands in the state described above, the amount of the air expansion in the ink chamber b is released from the atmosphere communication portion via the ink chamber a, and as shown in FIG.
Is released by the ink flowing out into the ink chamber b and the ink chamber a. That is, the ink chamber a has a function as a buffer chamber, and the ink holding capacity of the compressed ink absorber in the ink chamber a may be set in consideration of leakage from one ink chamber.

In this case, the ink in the ink chamber b and the ink chamber c is sequentially consumed, and the ink in the rearmost ink chamber d is consumed. Is consumed, and the ink is interrupted. Therefore, it is necessary to detect the remaining amount of ink in the ink chamber d. As shown in FIG. 16, a residual detection electrode is provided in the ink chamber d. The ink inlet was provided in the ink chamber b. In this embodiment, since the remaining amount of ink in only the ink chamber d is detected, almost all of the ink chamber b and the ink chamber c can be consumed except for the communicating part. Therefore, when the arrangement height of the residual detection electrodes is the same as that in the first embodiment, the remaining ink chambers not including the absorber remain when the remaining amount detection is activated as compared with the first embodiment. The amount of ink used can be reduced, and space can be used effectively.

In this embodiment, as in the first embodiment, ink can be refilled before the ink in the ink chamber a containing the absorber is cut off, and the ink can be reused.

<Third Embodiment> FIG. 18 is a view showing a third embodiment, in which a transparent or translucent material is used for the material of the tank wall, so that the remaining ink amount can be optically detected. It is. In this case, a reflection plate 42 such as a mirror for reflecting light is provided on an ink chamber wall in the ink chamber b, and a photosensor provided with a light emitting element 43 and a light receiving element 44 is provided outside the tank. The light emitting element 43 and the light receiving element 44 may be provided on a carriage, or may be provided at a home position having a recovery system.

In FIG. 18, light is emitted from the light emitting element 43 at a certain angle, and the light reflected by the reflector is received by the light receiving element 44. For example, an LED is used as the light emitting element 43, and a phototransistor or the like is used as the light receiving element 44. FIG. 18A shows a state in which the ink is almost full. In such a case, the light emitted from the light emitting element 43 is blocked by the ink in the ink chamber b, and almost no light reaches the light receiving element 44. And the detection output is small. However, when the ink is consumed and becomes as shown in FIG. 18B, the light output from the light emitting element 43 is hardly blocked, and the detection output from the light receiving element becomes high. Therefore, the light receiving element 4
When the light energy (detection output) received in step 4 becomes higher than a predetermined threshold value, an alarm device for prompting re-injection of the ink is activated.

FIG. 19 shows a modification in which the light-emitting element and the light-receiving element face each other with the ink tank interposed therebetween. FIG. 19A is a top view, and FIG.
(B) is a cross-sectional view. Also in this case, the material of the tank of the ink chamber b is transparent or translucent. In this example, there is no need to provide a reflector, and light is directly received, so that the detection sensitivity is good.

In this embodiment, one ink tank has been described. However, a plurality of recording heads capable of ejecting inks of different colors, for example, Bk (black), C (cyan), M (magenta), and Y (yellow) The present invention can also be applied to a color ink jet printing apparatus having a plurality of ink tanks for each color corresponding to the four heads, and to a printing head capable of discharging a plurality of colors of ink with one printing head.

At this time, the threshold value may be set differently for each color, or a specific absorption wavelength using a color filter or the like may be selected according to the color of the ink, and the light transmitted through the ink may be selected. The remaining amount of ink may be detected from the transmittance.

In this embodiment, an example in which the ink tank is replaced has been described. However, the present invention is applied to a printhead / ink tank integrated replacement system in which a printhead and an ink tank filled with a predetermined amount of ink are integrally formed. It is also possible.

<Fourth Embodiment> FIG. 20 shows a fourth embodiment of the present invention. This is a configuration in which the ink chamber b in the first embodiment is divided into two, and one of the ink chambers (ink chamber c) is replaceable. FIG. 20A shows a state where ink is consumed and detected by the remaining ink amount detection. here,
A new ink chamber c for replacement is prepared and replaced with the used ink chamber c. FIG. 20B shows a state in which the used ink chamber c has been removed and a new ink chamber c full of ink is about to be installed, and FIG. 20C shows a state in which the replacement has been completed. . At this time, the stopper 52 provided at the bottom of the ink chamber c is pierced at the injection port 5 above the ink chamber b, and the ink is supplied. This allows
No ink is injected using a syringe or dropper, so there is no need to worry about dirty hands.
The recording head can be kept connected to the recording head, and the replacement is minimal, so that the economy is good.

Also, in the fourth embodiment, the method for detecting the remaining amount of ink is not particularly limited to the method for measuring the resistance between the electrodes, but is an optical remaining amount detecting method as in the third embodiment. Or other detection means.

In this embodiment, an example in which the recording head and the ink tank are separable and exchanged is described. However, the recording head and the ink tank including the ink chambers a and b are integrally formed to be exchangeable. It is also possible.

[0066]

As described in detail above, according to the present invention,
An ink supply unit to the recording head and an air communication unit are provided,
In a state where a predetermined amount of ink remains in the ink chamber of an ink tank including an ink supply chamber containing an ink absorber and at least one ink chamber for communicating with the ink supply chamber and containing ink, the ink remaining in the ink tank is A decrease in the amount is detected, and the detection result is reported.

As a result, the recording operation can be stopped, the ink can be refilled into the ink chamber, and the ink tank can be reused.

[Brief description of the drawings]

FIG. 1 is a perspective view and a cross-sectional view of a part of an ink tank according to a first embodiment of the present invention, which is cut away.

FIG. 2 is a cross-sectional view illustrating a state in which a recording head and a replacement ink tank are mounted on a carriage according to the first embodiment of the present invention.

FIG. 3 is a perspective view of an example of an inkjet recording apparatus to which the present invention can be applied.

FIG. 4 is a diagram illustrating an initial state of the ink tank according to the first embodiment.

FIG. 5 is an explanatory diagram of ink consumption according to the first embodiment.

FIG. 6 is a modified example of the first embodiment.

FIG. 7 is a block diagram illustrating a configuration example of a control system of the apparatus.

FIG. 8 is a diagram illustrating a relationship between the remaining amount of ink and a resistance value between detection electrodes thereof.

FIG. 9 is a diagram illustrating a state at the time of detection of residual ink detection according to the first embodiment.

FIG. 10 is a diagram illustrating the internal pressure of an ink supply unit according to the first embodiment.

FIG. 11 is a diagram illustrating an example of an ink refilling method.

FIG. 12 is a diagram illustrating an ink buffer effect when the pressure is reduced according to the first embodiment.

FIG. 13 is a diagram illustrating the relationship between the amount of ink flowing out during pressure reduction.

FIG. 14 is an explanatory diagram of ink consumption according to the second embodiment.

FIG. 15 is a diagram illustrating ink consumption according to the second embodiment.

FIG. 16 is a diagram illustrating a state at the time of detection of remaining ink in the second embodiment.

FIG. 17 is an explanatory diagram of a case where ink is refilled after the ink in the ink chamber a has been used up.

FIG. 18 is a diagram illustrating detection of the remaining amount of ink in the third embodiment.

FIG. 19 is an explanatory diagram of a modification of the remaining ink amount detection in the third embodiment.

FIG. 20 is an explanatory diagram of an ink refilling method according to a fourth embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Ink tank 2 Ink supply part 3 Atmospheric communication part 4 Residual detection pin 5 Ink inlet 7 Ink absorber 51 Stopper

Continued on the front page (72) Inventor Norifumi Koitabashi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Shigetasu Nagoshi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon stock Inside the company (72) Inventor Masaya Uetsuki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Miyuki Matsubara 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. ( 72) Inventor Fumihiro Goto 3-30-2 Shimomaruko, Ota-ku, Tokyo Within Canon Inc. (56) References JP-A-61-22952 (JP, A) (58) Fields investigated (Int. Cl. ⁶⁾ , DB name) B41J 2/175

Claims (14)

(57) [Claims] 1. An ink supply chamber including an ink supply section to a recording head and an atmosphere communication section, the ink supply chamber including an ink absorber, and at least one ink chamber communicating with the ink supply chamber and containing ink. And an ink detecting means used to detect a decrease in the remaining amount of ink when a predetermined amount of ink remains in the ink chamber. 2. The ink tank according to claim 1, wherein ink is contained in the ink chamber. 3. The ink tank according to claim 1, wherein the ink tank is detachable from an ink jet recording apparatus. 4. The ink detecting device according to claim 3, wherein said ink detecting means is used to detect a decrease in the amount of remaining ink when an ink tank is mounted on said ink jet recording apparatus main body. Ink tank. 5. The ink tank according to claim 1, wherein the ink chamber includes an ink injection section for injecting ink. 6. The ink tank according to claim 1, wherein the ink supply unit is configured to be detachable from a recording head. 7. The ink tank according to claim 1, wherein a capillary force of the ink absorber is adjusted. 8. A recording head with an ink tank, wherein the recording head is connected to the ink supply section of the ink tank according to claim 1. 9. An ink jet recording apparatus which performs recording by using the recording head with an ink tank according to claim 8, wherein the ink is provided in the ink chamber and functions together with an ink detecting means provided in the ink tank. It is characterized by comprising: a remaining ink amount detecting means for detecting a low remaining ink amount when a predetermined amount remains, and a notifying means for notifying the low remaining ink amount based on a detection result of the remaining ink amount detecting means. Ink jet recording device. 10. The ink jet recording apparatus according to claim 9, further comprising a recording operation stopping means for stopping a recording operation based on a detection result of said ink remaining amount detecting means. 11. An ink jet recording apparatus according to claim 9, comprising the recording head with an ink jet according to claim 8. 12. The recording head according to claim 9, wherein the recording head ejects ink by using thermal energy, and includes a thermal energy generating unit for generating thermal energy to be applied to the ink. 12. The ink jet recording apparatus according to any one of claims 11 to 11. 13. An ink supply chamber including an ink supply section to a recording head and an atmosphere communication section, the ink supply chamber including an ink absorber, and at least one ink chamber communicating with the ink supply chamber and containing ink. A method for detecting a remaining amount of ink in a state where a predetermined amount of ink remains in the ink chamber, and reporting the detection result. Ink remaining amount detection method. 14. An ink supply chamber including an ink supply section to a recording head and an atmosphere communication section, and including an ink absorber, and at least one ink chamber communicating with the ink supply chamber and containing ink. A method for refilling ink in an ink tank, comprising: detecting a decrease in the remaining amount of ink in a state where a predetermined amount of ink remains in the ink chamber; and refilling the ink in the ink chamber based on the detection result. Ink replenishment method for the ink tank.