JPH05169674A - Ink jet recording apparatus and ink recording method - Google Patents

Abstract

PURPOSE:To maintain stable ink ejection performance for a long time for a recording head in separate type for which a plurality of ink tanks can be used alternately by a method wherein driving conditions for the recording head are changed in accordance with the frequency of use of the ink tanks for one recording chip. CONSTITUTION:In the case where an ink tank 1 is used, reference temperature for controlling the temperature is set at a first set temperature T1. As the ink in the first ink tank 1 is consumed and the tank 1 is replaced by a tank 2 and as the tank 2 is mounted to the same recording chip, driving condition for the recording head is changed downward by setting the reference temperature for controlling the temperature at a second set temperature T2. Thereby, high quality recording images can be formed for duration of the recording by the tank 2 with less variation in recording density and with efficiency relatively better than the previous recording. When a tank 3 is mounted likewise, the driving condition is changed downward further with setting made at a third set temperature T3. By employing methods as mentioned above, a large amount of ink, larger than in the case of mounting a single ink tank, can be used without allowing changes to occur in its characteristic, and formation of quality recording images can be made stably for a long time with the recording chip.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink recording apparatus using a recording head in which an ink tank for supplying ink to a recording head section is integrated, and more specifically, it is suitable for the number of ink tanks used. It relates to an invention for achieving ink recording. The present invention relates to an ink recording apparatus applicable to a printer alone, a copying machine, a word processor, a personal computer, a facsimile, or a composite machine of these.

[0002]

2. Description of the Related Art Conventionally, an ink supply mechanism of an ink recording apparatus uses a recording head for a long period of time and uses a so-called permanent recording head in which a large ink cartridge is replaceable with respect to an ink supply path to the recording head. In this case, when a recording head with an ink tank integrated in the recording head is detachable from the device and when the recording head is replaced as it is, ink is stored in the ink tank of this integrated recording head. It is roughly classified into the case of re-filling in which it is refilled only at a predetermined position or manually by the user.

An outline of the former configuration will be described using the apparatus of FIG. 4 provided by the applicant of the present application.

FIG. 4 is a schematic view of an ink jet recording apparatus IJRA to which the present invention can be applied. The lead skew 5005 is a helix line that rotates via driving force transmission gears 5011 and 5009 in association with forward and reverse rotations of a drive motor 5013. Groove 50
Carriage HC that engages with 04 is a pin (not shown)
And is reciprocated in the directions of arrows a and b. A paper pressing plate 5002 presses the paper against the platen 5000 in the carriage moving direction. 5007,5008
Is a home position detecting means for confirming the presence of the carriage lever 5006 in this area by a photo coupler and switching the rotation direction of the motor 5013. 5016
Is a cap member 502 for capping the front of the recording head.
Reference numeral 5015 is a member for supporting the inside of the cap, and 5015 is a suction means for sucking the inside of the cap to perform suction recovery of the recording head through the inside-cap opening 5023. Reference numeral 5017 is a cleaning blade, and 5019 is a member that allows this blade to move in the front-rear direction, and these are supported by a main body support plate 5018. Reference numeral 5012 denotes a lever for starting suction for suction recovery, which moves in accordance with the movement of the cam 5020 that engages with the carriage, and the driving force from the drive motor is controlled by known transmission means such as clutch switching. To be done. These capping, cleaning, and suction recovery operations are performed by the lead screen 5 when the carriage comes to the home position side area.
By the action of 005, desired processing can be performed at those corresponding positions.

In addition, as a driving means of the ink jet recording head, an electrothermal converter or a photothermal converter is used to generate thermal energy to cause film boiling in the ink that exceeds nucleate boiling. A method of discharging ink droplets by stable volume expansion has been put into practical use. In other methods, a method of ejecting ink using an electromechanical converter has been partially put into practical use.

[0006]

However, although there are many applications for inventions for replenishing ink arbitrarily or periodically replenishing it by tank exchange, the relationship between the replenishing ink and the recording state was examined. The only thing is that it is against the contamination of garbage.

The present invention is applied to a recording chip of a recording head (for example, a plurality of or a single ejection port, a liquid passage, a liquid chamber, an ejection element such as an electrothermal conversion element, an electric drive signal supply wiring, etc.). The research was conducted by clarifying the phenomenon that the fluctuation of the ink ejection state occurs in a relatively short period when the ink supply is performed arbitrarily or periodically. Also, after the ink in the ink tank is consumed,
In a configuration in which a plurality of ink tanks are replaced and recording is restarted, the stable stable recording period tends to be shortened as compared with the case where a large ink tank having a recordable amount of ink in the recording chip is used. It was confirmed that it showed. In view of this, the inventors conducted research, and it was confirmed that some trouble occurred in the ink supply state before the replacement of the ink tank and the ejection element itself, which was the cause.

Specifically, this is due to a change in the ink ejection amount and a change in the minimum drive voltage due to a change in the characteristics of the ejection element itself, which is the ejection means. In particular, it has an electrothermal converter. In the ink recording head, this factor greatly changes the recording state. Therefore, in the case where the ink is supplied arbitrarily or periodically (especially when the electrothermal converter is used), it is important to maintain stable ejection performance for a long period of time and achieve a long life of the recording head. It becomes an issue.

The object of the present invention is to solve the above-mentioned problems when the ink supply is performed arbitrarily or periodically, and is not affected by the degree of re-ink supply.
An object of the present invention is to provide an ink jet recording apparatus and an ink recording method capable of maintaining stable ejection performance for a long period of time and effectively putting the advantages of re-ink supply into practical use.

Another object of the present invention is to provide an ink jet recording apparatus and an ink recording method capable of suppressing a change in the ejection characteristics of the head caused by the degree of re-ink supply and substantially extending the life of the recording head. ..

Another object of the present invention is to change the driving conditions of the recording head in response to the replacement of the ink tank for re-ink supply, and preferably to perform cumulative recording in which the ink tanks using the driving conditions are used for recording. It is an object of the present invention to provide an ink jet recording apparatus and an ink recording method that are changed according to the above conditions to realize long-term use of a recording head and stable recording characteristics.

Still another object of the present invention is to change the driving condition of the recording head in accordance with the conditions of both the replacement of the ink tank for re-ink supply and the replacement of the recording chip, preferably the cumulative recording. It is an object of the present invention to provide an ink jet recording apparatus and an ink recording method that realize stable recording characteristics over a long period of time by changing the driving conditions.

[0013]

SUMMARY OF THE INVENTION The present invention achieves the above objects.
What is claimed is: 1. An inkjet recording apparatus that performs recording using a recording head that performs recording in a state where a recording chip having an ink ejecting section and an ink tank that contains ink are integrated, wherein the recording head is an ink tank for the recording chip. Is a separable recording head in which a plurality of the recording heads can be exchanged and used, and an ink jet recording apparatus comprising means for changing drive conditions of the recording head according to the number of times the ink tank is used for one recording chip. ..

According to the present invention, relatively stable recording can be performed without being affected by the replacement of the ink tank for re-ink supply. For example, even if the ink tank is replaced during recording, it is possible to prevent image changes that would occur in one page,
If the ink tank is replaced while recording a plurality of the same images, it is possible to achieve unified recording of the same images.

Among the present inventions, the inventions of particular note are as follows.

Since the changing means has a mechanism for correcting the driving condition of the mounted recording head in response to the replacement of the recording chip with the apparatus, it is unnecessary for the replaced recording head. It is possible to stabilize the recording by using the integrated ink tank without applying a load and to bring the recording into an appropriate state.

Further, the recording head is provided with a plurality of ejection ports as the ink ejection section and an electrothermal converter which generates thermal energy corresponding to each ejection port to form bubbles in the ink. In the configuration in which the ink jet recording apparatus is provided with the means for supplying the drive signal for driving the electrothermal converter according to the recording signal, each of the above inventions can not only optimize the ink consumption efficiency in the ink tank, Since an appropriate driving condition is given to the heat conversion element for a long period of time to prevent the overload state from occurring and the recording characteristics can be stabilized at a high level, it is possible to achieve a long life of the recording head as a whole.

The method of the present invention including ink refilling for replacing the ink tank is a higher invention of the present invention.
It can be defined as "the number of times the ink is supplied to the recording chip by the ink tank". Also in the present invention, the above-described effects can be obtained similarly.

In the case where the target of changing the drive signal is a drive signal in which the preheating signal to be supplied to the electrothermal converter and the bubble forming main signal are separated by an interval, in particular, the preheating signal of the preheating signal is changed. A typical example is to reduce the supply energy according to the number of times of ink supply.
When this drive signal is used, the amount of ejected ink can be changed in a minute range while preventing excessive temperature rise of the ink ejecting section, so that the characteristics can be further ensured. Further, when the driving conditions for ink ejection are set as the setting reference for adjusting the temperature of the recording chip or the ink, the setting reference may be lowered according to the number of times of ink supply as the above change. In this temperature adjustment, the temperature of the ink and its surroundings is relatively changed, so that the ink ejection amount can be optimized with respect to the ejection amount change, and the life of the recording head can be extended. Note that specific examples of these more preferable changes can be understood from the description of the following embodiments.

In addition, the invention of the present invention, which is more accurate, is an ink recording method in which ink is supplied to a recording chip having an ink ejecting portion by using an ink tank to perform recording. An ink recording method is characterized in that recording is performed by changing an ink ejection drive condition of the recording chip in accordance with the number of times of ink supply from the ink tank and the ink consumption rate in the mounted ink tank. This can make the effect of the present invention more precise, and can be understood from the description in the following examples.

The recording head according to the present invention is roughly divided into an ink recording section and an ink tank section for supplying ink to the ink recording section. The effect of the present invention is more remarkable when the size is reduced, but the present invention is not limited to this. Further, the attachment / detachment mechanism between the ink recording portion and the ink tank portion and the discrimination mechanism between them include all the ones capable of carrying out the above inventive idea, and are not limited to the following embodiments.

[0022]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 5 is a sectional view of a main part including a carriage carrying a recording head used for carrying out the present invention. A feature of this configuration is that the ink tank T and the recording chip have an electrical connection structure for discriminating the new mounting of the ink tank T when the recording chip is mounted on the carriage. Has a connection configuration that enables supply to the control unit of the device. Other components are a design-changeable positioning mechanism, attachment / detachment mechanism, atmosphere communication unit, and the like.

In the embodiment shown in FIG. 5, the ink tank T has a urethane sponge 9 which is an ink-absorbing continuous fine porous body, and an ink supply port which serves as an ink supply unit and is elastically pressed against the recording chip. The elastic engagement member 12 located outside of the air supply unit 1 and the air communication unit 1 having a bent shape for communicating the inside with the outside air at the end opposite to the ink supply unit.
It has 0. This basic structure is disclosed in JP-A-3-175.
It is disclosed in Japanese Patent No. 051.

In this structure, compared with the above-mentioned known structure, the tank capacity is obtained by dividing the usable ink amount with respect to the life of the recording chip, thereby reducing the possibility of the carriage and downsizing the apparatus. is doing. Furthermore, the ink tank T
A new mounting electrical contact TC for making an electrical connection in a coupled state with the recording chip is provided at the end.

The basic structure of the recording chip to which the ink tank T is mounted is likewise disclosed in Japanese Patent Laid-Open No. 3-175051. Specifically, the orifice plate and the top plate member 1, which is an integral member of the ink path forming member, the ink supply path forming member 7 including the filter 8, and the electrothermal converter 3.
And a base plate BP on which the plate 4 is mounted. The top plate member 1 includes a plurality of ejection openings 5, an ink path communicating with each of the ejection openings 5, and a common liquid compartment 2 formed by molding a common liquid compartment 2 communicating with the ink path. The discharge port 5 is post-processed by the excimer laser. Also, the base plate BP
Is the head positioning portions 17 and 18 of the carriage APP,
Predetermined engagement is performed to maintain the positioning of the ejection portion of the recording head with respect to the recording paper with high accuracy. Ink supply path forming member 7
Is provided with a filter 8 and an O-ring 14 at the connecting portion with the ink tank T to prevent ink leakage when the ink tank is attached or detached, and stabilize the ink supply state.

This recording chip further has a different structure as compared with the above-mentioned known structure. That is, the filter 8 is
Since the sponge 9 in the ink tank T is pressed into contact with the sponge 9, the spout 9 slightly protrudes from the supply path forming member 7 to stably supply the ink from the sponge 9. Therefore, when the ink tank is detached, the filter contact portion of the sponge 9 expands and the ink remaining on the surface of the filter 8 can be absorbed in the tank, and at the same time, the residual ink in the ink tank does not leak to the outside. .. Further, the electrical contact AP, which is an electric signal supply unit from the device side to the silicon plate 4, is a flexible electrical contact H which is turned on the surface of the base plate BP opposite to the silicon plate 4.
This is a configuration in which the electrothermal converter 3 can be driven through elastic connection with C3 and electrical connection of the wire bonding 21. Therefore, the base plate BP itself can be made smaller than the conventional one. Since the recording chip is small and the wiring portion is concentrated, a portion that the operator touches with is provided as a frame body, and the electrical contact T of the ink tank is provided on the frame body.
A convex coupling portion 15 of the tank and the recording chip (corresponding to the concave portion 16 on the tank side) is formed in the vicinity of the electric contact HC1 connected to C and secures a stable electric connection state between them. The other of the frames has a pin HC2 connected to the microswitch ACP of the carriage APP, and is configured to supply a signal for determining the presence or new mounting of the recording chip to the apparatus.

Reference numeral 11 denotes a pressurizing means which pressurizes the ink tank T in the direction of the arrow to make the connection of the ink supply portion constant. As the pressurizing means, any of well-known two-member detachable structure may be adopted.

(Explanation of Change in Ejection Characteristics) Here, a change in the recording state of the ink jet recording head, which is a technical problem of the present invention, will be described with reference to FIG. FIG. 6 shows changes in the ink discharge amount and the drive minimum voltage when printing of one recording head using an electrothermal converter is durable. In this figure, the solid line 50 shows the change in the ink ejection amount when printing is performed under constant drive conditions until the recording limit is reached by continuously supplying ink, and in this figure, at each recording time point for obtaining the ejection amount of the solid line. The voltage that is the minimum drive energy required for ejecting ink (hereinafter referred to as the minimum drive voltage V _sh ) is indicated by a broken line 60.

As can be seen from the solid line 50, the ink discharge amount at the start of recording is the minimum discharge amount, the ink discharge amount greatly increases in the first half of the half life, and then gradually increases and then slightly. Will decrease. Normal commercial products are
Since it is necessary to satisfy this initial discharge amount, FIG.
Although the pre-processing for obtaining the minimum ejection amount is performed, no treatment is taken against the change in the ink ejection amount.

In response to this change, if the initial minimum ejection amount is increased in order to stabilize the ink ejection amount under a constant driving condition, the life of the recording head becomes extremely short. Then, considering the ink ejection amount at each time point, when the minimum drive voltage V _sh is seen by changing the voltage of the pulse voltage for a constant drive time,
As can be seen from the broken line 60, it gradually decreases from the beginning of recording,
It was found that the electric potential suddenly became high as the ink discharge amount started to decrease. In this figure, the reason why the solid line 50 is cut off halfway with respect to the durable print number is that the time point at which the ink can be ejected at a constant voltage has exceeded the minimum drive voltage V _sh .

It can be expected that the ink jet recording head behaves as shown in FIG. 6 as follows. The heat generating portion and the ink passage used in the ink jet recording chip have a low affinity with the ink in the initial stage, and therefore the heat conduction efficiency and the conformability to the ink are poor. Due to heat due to printing durability and changes with time, this affinity gradually improves, heat conduction efficiency improves, and bubble formation stabilizes, so that the ink ejection amount increases. When the printing durability number is further increased, impurities and the like in the ink are gradually deposited on the surface of the heat generating portion, and so-called kogation occurs and progresses, so that the heat transfer efficiency to the ink is reduced and the ink ejection amount is reduced. Further, at the same time, the minimum voltage V _sh for driving the heater necessary for ejecting ink rises, so in the case of constant voltage driving,
In the life of the recording head, stable ejection characteristics may not be obtained, or even ejection may not be performed at all. Therefore, in order to maintain stable ejection performance in the inkjet recording head for a long period of time and to extend the life of the recording head, the drive conditions of the head are changed according to the progress of printing durability in order to suppress changes in the ejection characteristics of the head. It can be understood that doing is effective.

In the present invention, when the recording chip / ink tank separation type head structure is adopted, the above-mentioned fluctuation of the ink discharge amount is
By distributing the amount of ink supply that can be used during printing durability to the replacement ink tank, we focused on the fact that the variation range of the recording characteristics became relatively small with respect to this number of replacements, and the ink discharge amount Since the proportions are substantially proportional to each other, it is possible to achieve efficient printing by changing the driving conditions of the head according to the number of times the ink tank is replaced with respect to one printing chip.

(Outline of temperature control) In a specific example of temperature control applied to the following embodiment, an environment temperature sensor for measuring the environment temperature is provided on the main body side, and fluctuations in the temperature of the ink at the ejection portion are controlled by the ink. By estimating and predicting past, present, and future ink temperatures by calculating the discharge energy and the supply energy of the sub-heater for keeping the print head warm,
An example is one that stabilizes ejection according to the ink temperature. This is based on a temperature change table that pre-calculates the input energy in the past to future range, which is substantially related to the thermal time constant of the ink ejection unit including the print head and ink and the ink temperature change of the ejection unit. It is estimated and predicted by doing.

Further, the structure for controlling the temperature using the drive pulse as shown in FIG. 12 is also applicable to the present invention.
FIG. 12 is a diagram for explaining a divided pulse relating to an embodiment described later. In the figure, VOP is a drive voltage, P1
Is the pulse width of the first pulse (hereinafter referred to as the prepulse) of the plurality of divided heat pulses, P2 is the interval time, and P3 is the pulse width of the second pulse (hereinafter referred to as the main pulse). T1, T2, T3 are P1,
The time for determining P2 and P3 is shown. The driving voltage VOP is one of the electric energy necessary for the electrothermal converter to which this voltage is applied to generate heat energy in the ink in the ink liquid path formed by the heater board and the top plate. is there. The value depends on the area of the electrothermal converter, the resistance value, the film structure and the liquid path structure of the recording head.

This PWM ejection amount control can be said to be a pre-pulse width modulation driving method, and when ejecting one ink droplet, P
Pulses are sequentially applied in the widths of 1, P2, and P3, and the width of the pre-pulse is modulated according to the ink temperature. The pre-pulse is a pulse mainly for controlling the ink temperature in the liquid path, and plays an important role in the ejection amount control of this embodiment. The preheat pulse width is preferably set to a value that does not cause a bubbling phenomenon in the ink due to the thermal energy generated by the electrothermal converter when it is applied. The interval time secures a time for energy transfer of the pre-pulse to the ink in the ink liquid path and prevents excessive temperature rise. The main pulse is for causing bubbling in the ink in the liquid passage to eject the ink from the ejection port, and its width P3 is the area of the electrothermal converter, the resistance value,
It is preferably determined by the film structure and the structure of the ink liquid path of the recording head.

For example, the action of the pre-pulse in the ink jet recording head as shown in FIG. 5 will be described. When the main pulse width P3 is 4.114 [μsec] and the prepulse width P1 is changed in the range of 0 to 3.000 [μsec] under a constant voltage with the drive voltage VOP set to 18.0 (V), The discharge amount Vd [pl / d as shown in FIG.
Rop] and the prepulse width P1 [μsec] can be obtained. This figure is a diagram showing the pre-pulse width dependence of the ejection amount. In the figure, V0 represents the ejection amount when P1 = 0 [μsec], and this value is determined by the head structure shown in FIG. Incidentally, V0 in this embodiment is the ambient temperature TR = 2.
At the temperature of 5 ° C., V0 = 18.0 [pl / drop].

As shown by the curve a in FIG. 13, the ejection amount Vd linearly increases from the pulse width P1 of 0 to P1LMT in accordance with the increase of the pulse width P1 of the pre-pulse, and the pulse width P1 of P1LMT. In the larger range, the change loses linearity and saturates at the pulse width P1MAX and becomes maximum. In this way, the range up to the pulse width P1LMT where the change in the ejection amount Vd with respect to the change in the pulse width P1 shows linearity is the pulse width P1.
Is effective as a range in which the discharge amount can be easily controlled by changing Incidentally, in the present embodiment shown by the curve a, P1LMT = 1.87 (μs), and the discharge amount at this time was VLMT = 24.0 [pl / drop]. Also,
The pulse width P1MAX when the discharge amount Vd becomes saturated is
P1MAX = 2.1 [μs], and the discharge amount VMA at this time
x = 25.5 [pl / drop]. When the pulse width is larger than P1MAX, the ejection amount Vd becomes smaller than VMAX. When a pre-pulse having a pulse width in the above range is applied, this phenomenon causes minute foaming (state immediately before film boiling) on the electrothermal converter, and the next main pulse is applied before the bubbles disappear. The discharge amount becomes small because the minute bubbles disturb the bubbling due to the main pulse. This area is called a pre-foaming area, and it is difficult to control the ejection amount through the pre-pulse in this area. If the slope of the straight line showing the relationship between the ejection amount and the pulse width in the range of P1 = 0 to P1 LMT [μs] shown in FIG.・ Dro
p]. This coefficient KP is determined by the head structure, driving conditions, ink physical properties, etc., regardless of temperature. That is, in FIG. 13, the curves b and c show the case of other recording heads, and it can be seen that the ejection characteristics change when the recording heads are different. As described above, since the upper limit value P1LMT of the pre-pulse P1 is different when the recording heads are different, the upper limit value P1LMT for each recording head is set and the ejection amount control is performed. By the way, in the recording head and ink shown by the curve a in this embodiment, KP = 3.209 [pl / μsec · drop].
Met.

On the other hand, another factor that determines the ejection amount of the ink jet recording head is the ink temperature of the ejection portion (the temperature of the recording head may be a substitute). Figure 10
FIG. 4 is a diagram showing the temperature dependence of the discharge amount. Curve a in the figure
As shown in, the ejection amount Vd increases linearly with the increase of the temperature TH of the recording head (in this case, it is equal to the ink temperature of the ejection portion due to the static temperature characteristic). If the slope of this straight line is defined as the temperature dependence coefficient, the temperature dependence coefficient: KT = ΔVdT / ΔTH [pl / ° C. drop]. This coefficient KT is determined by the structure of the head, the physical properties of the ink, etc., not by the driving conditions. Also in FIG. 11, curves b and c show cases of other recording heads. In the recording head of this embodiment, KT = 0.3 [pl / ° C.
drop].

In FIG. 11, the minimum discharge amount of V ₀ is shown, and the reference temperature T ₀ for temperature adjustment at this time is the minimum heat retention temperature of the recording head. Above this temperature, the discharge amount is considerably proportional to the temperature. It exhibits increasing properties. This temperature change includes a normal temperature adjustment method for keeping the print head warm when the ink temperature of the ejection portion is low, PWM control, and the like. Usually, the heat retention temperature is set to a temperature higher than the normal environment temperature (for example, 35 to 40 degrees C). Basically, since this temperature condition only needs to be satisfied when ink is ejected, it is preferable to control the ejection amount with a pre-pulse smaller than the pre-foaming region as described above, and the temperature range in which PWM control is possible is limited to some extent. Therefore, considering the self-heating of the recording head, it is easier to stabilize the ejection amount by setting the heat retention temperature higher.

The flowcharts of FIGS. 1 to 3 and FIGS.
A specific embodiment will be described by using the principle description of FIG.

(First Embodiment) An embodiment in which the present invention is used for controlling the discharge amount of a monochrome printer will be described below.
In monochrome printers, it is especially important to prevent print quality deterioration due to bleeding, feathering, etc. while satisfying the allowable print density. Therefore, it is possible to suppress fluctuations in discharge amount while keeping the minimum discharge amount of ink. is necessary.

FIG. 7 is a principle diagram of correction in the case of suppressing fluctuations in the ejection amount while guaranteeing the minimum ejection amount. A broken line 70 in FIG. 7 shows a change in the ink ejection amount under a constant drive condition in which the present embodiment is not carried out. In this embodiment, as one means for controlling the ejection amount, a method of changing the temperature control temperature setting of the recording head is adopted. As can be seen from the description of FIG. 11, the relationship between the print head temperature and the ink ejection amount is almost proportional, so in this embodiment, the reference set temperatures for temperature adjustment are second, third, and so on in order from the initial ink tank 1. As described above, the setting temperature is changed to a lower set temperature each time the number of replacements is increased. In FIG. 7, it is assumed that five ink tanks can be used for one recording chip. The ejection amount control as shown in can be realized by changing the temperature adjustment set temperature of the recording head when the ink tank is replaced.

Specifically, since the ink tank 1 is first applied to the recording chip, it ejects ink almost in the same manner as the conventional ink ejection amount curve. Since the ink tank 1 is applied to the recording chip, the driving condition of the recording head is
The reference temperature for temperature control is set to the first set temperature T1 (for example, 40 degrees C). Next, the ink tank 1 is consumed, and the same recording chip is replaced with the ink tank 1,
When the ink tank 2 is installed, the drive condition of the recording head is that the reference temperature for temperature control is set to the second set temperature T2 (for example,
The lower limit is changed to 38 degrees C). As a result, the recording period of the ink tank 2 is relatively more efficient than before and the change in recording density can be reduced, and a high-quality recorded image can be formed. Similarly, when the ink tank 3 is attached, the lower limit is changed to the third set temperature T3 (for example, 36 degrees C), and when the ink tank 4 is attached, the fourth set temperature T4 (for example,
When the lower limit is changed to 33 degrees C) and the ink tank 5 is mounted, the lower limit is changed to the fifth set temperature T5 (for example, 30 degrees C). As a result, it is possible to use a larger amount of ink than the total amount of ink in one ink tank attached to the recording chip without causing a change in the ink characteristics, and to use the recording chip for a long period of time to obtain a high-quality recorded image. It can be stably formed. Moreover, as can be seen from the recording discharge amount change curves 80 to 84 of the respective ink tanks of FIG. 7, in this embodiment, the minimum discharge amount (represented by the straight line 86) is satisfied regardless of which ink tank is used. Therefore, the difference from the integrated value of the broken line 70 becomes clear. The number of ink tanks applicable to the recording chip is 3 or more.
It is preferable that the number is 0, and the frequency of replacement is preferably within an appropriate range. A curve 85 in the figure shows the discharge amount of the sixth ink tank, and the sixth set temperature T6 at this time is set to 28 degrees C.
It may be the same as the fifth set temperature T5. The change of the driving condition of the present invention is included in the present invention because the efficiency of ink consumption can be achieved by changing the initial condition in this way for one recording chip. Is.

FIG. 1 shows an example of a flow chart in the case of changing the set temperature for temperature control described above. The flowchart shown here is applied to a recording apparatus (see FIG. 5) having a mechanism in which a user can independently take out an ink tank from a carriage when ink is no longer ejected and a new ink tank can be mounted. If the ink ejection is not recovered even after the recovery operation is performed, the operator starts an ink tank replacement operation. At this time, when the attached ink tank is detached from the recording chip, the presence / absence of the ink tank in the carriage is determined. When the absence of the tank is detected in step S1, the ink tank counter adds +1 to Before installing a new ink tank, check whether the number N of ink tanks that can be installed in the recording chip has exceeded the process S
It is determined by 2. If the number N of ink tanks is exceeded in step S2, the replacement of the recording chip itself is warned in step S4, and the recording chip is replaced. As a result, when the recording chip is removed from the device for replacement, step S
5, the temperature setting value for temperature control is initialized before the new recording chip is mounted, that is, the recording condition of the new ink tank of the new recording chip is set to the first setting temperature T1 in step S6.
In the ink tank counter reset step S7, the ink tank counter is set to 1. In this state, the apparatus waits for mounting a new recording chip in step S5. In step S5, if there is no replacement warning or a new recording chip is installed (the warning is reset at this point), it is determined in step S8 whether a new ink tank is installed. here,
When it is confirmed that a new ink tank has been installed (the warning is reset at this point), in step S9, the temperature setting value for temperature adjustment is set according to the ink tank counter, for example,
Change as described in FIG. As a result, the preparation for the ink tank and the recording chip of the apparatus is completed, and the apparatus ends the change of the recording condition. After that, preliminary ejection and recovery of the recording head are performed according to desired conditions as necessary, and the printer apparatus becomes a recordable state (step S10).

In this embodiment, before mounting a new recording chip or a new ink tank, the members to be mounted are predicted and the preparation is performed in advance, so that there is no waiting time for the operator, which is preferable. is there.

(Second Embodiment) Next, an embodiment which is particularly effective when the present invention is used for controlling the discharge amount of a color printer will be described below. In a color printer, color balance is particularly important, and therefore, it is particularly important to suppress fluctuations in ink discharge amount.

FIG. 8 is a principle diagram of correction in the case of suppressing the fluctuation of the discharge amount to the minimum. As one means for performing such ejection amount control, there is a method of changing the drive pulse width setting of the recording head. Particularly effective one is P of FIG. 12 described above.
The rectangular voltage pulse used for the multi-pulse drive in the WM control enables more accurate discharge amount control as shown in FIG.

FIG. 2 shows an example of a flowchart for performing such control. The flow chart shown here relates to a recording apparatus of a type in which a remaining amount detecting mechanism for detecting the absence of ink in the ink tank in advance and warning the user to replace the ink tank can be used for the ink tank replacement.

In FIG. 2, an ink remaining amount detecting operation step S1 for periodically discriminating the ink remaining amount in the ink tank (or the recording chip) is performed, and when the absence of ink is detected, the ink tank counter is used. In step S2, it is determined whether or not the number of ink tanks N that can be attached to the recording chip in use is reached. In step S2, the number of ink tanks N
If it is, replace the recording chip itself in step S3.
To warn you and let you replace the recording chip. In any case, after step S2, the ink tank should be replaced in step S2.
A warning is given in 4 and a new ink tank is installed. In step S6, when the recording chip is separated from the carriage, the PWM setting value is initialized before the new recording chip is attached to the apparatus, that is, the recording condition by the new ink tank of the new recording chip is first set in step S7. The pulse width P _{11 is set to} 1 in the ink tank counter reset step S5. In this state, the apparatus waits for mounting of a new recording chip in step S6. In step S6, if there is no recording chip replacement warning or a new recording chip is installed (this warning is reset at this point), it is determined in step S8 whether the used ink tank has been removed. This can prevent the re-installation of the used ink tank by utilizing the remaining ink amount detection. Here, when this separation is confirmed, the ink tank counter +
1 is added in step S9, and the apparatus stands by in step S10 until a new ink tank is installed. When it is confirmed that a new ink tank has been installed (the warning is reset at this point), in step 11, the Nth set pulse width P ₁ N (N is the ink tank In the order of use, the pulse width P ₁ N decreases as N increases) is set. This allows multiple recording heads to
Even if the recording chip and / or the ink tank is arbitrarily changed according to the consumption, the density balance of the color recorded image can be suppressed within a stable range.

As a result, the preparation for the ink tank and the recording chip of the apparatus is completed, and the apparatus ends the change of the recording condition. After that, preliminary ejection and recovery of the recording head are performed according to desired conditions as necessary, and the printer apparatus becomes in a recordable state (step S12).

Although this embodiment applies a plurality of conditions, the present invention is particularly suitable for color recording, and PWM control is optimum for highly accurate setting change for the electrothermal converter. ..

(Third Embodiment) An embodiment for carrying out the present invention mainly for the purpose of achieving a long life of the recording head of a monochrome printer will be described. Although this is different from the stabilization of the discharge amount described above, it is effective as a means for solving the problem found in FIG. As described with reference to FIG. 6, in the inkjet recording head, the minimum driving voltage rises due to printing durability, and therefore when the driving voltage is constant, ejection cannot be performed at a certain time, and the life ends. By delaying this time, the life of the recording head can be extended. FIG. 9 is a principle diagram of drive voltage correction for changing the drive voltage and delaying the unstable / incapable period of ejection. This principle can be applied not only to electrothermal converters, but also to electromechanical converters.

In FIG. 9, P ₁ is the upper limit number of prints in the printable range in FIG. 6, and P ₂ is the life of the print head. The solid lines 100, 101, and 102 represent the drive voltage changes of the embodiment of the present invention showing that recording can be performed from the number of sheets P ₁ to the time when the ejection unstable region and the life period P ₂ are exceeded. _{Shows the} minimum drive voltage V _sh in FIG. The solid line 103 shows the outline of the change in the ink ejection amount in this embodiment.

Normally, the drive voltage of the recording head is set to 1.2 times the minimum drive voltage V _sh , and constant drive is performed. However, in this embodiment, it is considered that the initial drive voltage is not effectively used. Then, for the initial recording, the initial minimum drive voltage V _sh
Is applied to prolong the life of the recording head and at the same time stabilize the ink ejection amount. After the ejection unstable region, a voltage (solid lines 101, 10) that exceeds the minimum drive voltage V _sh in that region.
2) is gradually increased and supplied. As a result, as can be seen from the solid line 103, although the ejection amount slightly increases until the ejection instable region where the recording failure has occurred and the life period P ₂ is exceeded, stable recording can be performed, It can be seen that the life of the head has been extended.

FIG. 3 shows an example of a flowchart of this embodiment. The flowchart shown here is the same as that of FIG. 1, and only the execution contents in steps S6 and S9 are different, and therefore only this part will be described. In this embodiment, the number of ink tanks used is increased with respect to one recording chip, and N is increased from 5 to 7, as compared with the above-described embodiments. In the present embodiment, the recording condition is changed so that the voltages of the solid lines 101 and 102 are supplied to N and 6, 7. The present invention also includes a modification of a part of the ink tank that uses the printing condition as described above. Therefore, in step S6 in FIG. 3, the recording condition is changed to the minimum drive voltage V _sh for initial recording.
In FIG. 9, when N is 6 and 7, the voltages of the solid lines 101 and 102 are respectively, and when N is 5 or less, the minimum drive voltage V _sh of initial recording.
Will be selected to record.

As a result, the supply drive voltage can effectively improve the ink consumption efficiency and extend the life of the recording chip.

FIG. 9 can be used to explain the contents of another embodiment. That is, this is an example that is easier to understand in an embodiment in which the driving conditions are changed to increase the ink ejection amount in the latter half of the ink supply in order to achieve the long life of the recording head. Only the parts different from the parts described above will be described below. In the description of this example, the solid line 103 described above is the minimum drive voltage V _sh in FIG. 6, and the broken line 104 is a virtual appropriate drive voltage V _op that is 1.2 times the minimum drive voltage V _sh for performing stable ejection. As shown in.

Therefore, after the above-mentioned unstable ejection area of the recording chip, stable ejection cannot be performed at a constant voltage as indicated by the solid line 103, but in the present embodiment, the solid line 1 is used.
Since the proper drive voltage V _op exceeding 03 is supplied, the ejection is stable and the stable recording period can be increased. Furthermore,
Even when the life period P ₂ is _exceeded , the appropriate drive voltage V _op that exceeds the minimum drive voltage V _{sh in} the solid line 103 is supplied, so that the recording head can reliably discharge and substantially. In addition, the life is extended and the remaining ink can be effectively used for recording. In this case, the appropriate drive voltage V _op
9 is a curve, the solid lines 102, 102, and 103 are used in FIG. 9 in order to change the recording conditions in a stepwise manner. However, in a curve or as shown in FIG. As described above, the driving condition may be changed according to the curved shape or a combination thereof. The flow chart of this embodiment can be performed in the same manner as the flow chart of FIG.

(Other Embodiments) The present invention can easily be recalled from a number of embodiments in which the driving conditions are changed, and includes all the embodiments based on the above-mentioned idea. For example, in the actual sisters employing a plurality of the above-mentioned embodiments, further stabilization and long life can be achieved, and the following method can be mentioned.

FIG. 10 shows the start and end of use of each ink tank when an ink tank having an ink holding portion for generating a negative pressure is used like the sponge 9 described in FIG. 5 in the ink tank. The magnitude of the negative pressure is different in the vicinity, and the effect of equalizing the average value of the ink ejection amount due to this is utilized. In this case, the configuration of the present invention is more preferable. However, when the ink discharge amount drastically decreases near the end due to the negative pressure fluctuation, the above-mentioned corrections are changed to one ink tank in use to further improve the stability. Since this is achieved, it is a more preferable invention. In any case, it is more practical to further change the recording condition depending on the number of times of ink supply to the recording chip by the ink tank according to the amount of ink in the ink tank of the present invention. Although the above-described embodiment assumes a recording head exchange type, the present invention is also effective for a permanent type apparatus in which the recording head can be used for an extremely long period of time.

(Recording Head Discrimination Method) Here, a configuration for detecting or discriminating the new mounting state of the ink tank and the recording chip of the recording head will be described. Since these are not normally taken out from the printer unless the print head causes a print defect, a method of determining the re-installed one as a new one may be used. However, there is a case where the attachment / detachment is occasionally performed during the operation, so a configuration capable of determining the suitability will be described below.

By configuring the operator to turn on the reset key that enables recording for each of the above-mentioned replacement warnings, it is possible to determine a new ink tank or recording chip, and by using this ON signal, The ink tank counter and the recording chip may be initialized. This configuration is particularly suitable for ink supply in which the ink tank is reused and ink is refilled. In another method, an electric resistance that breaks due to a large number of energizations is provided in a recording chip or an ink tank, and using this, it is confirmed that it is new with a single energization, and after confirmation, multiple energizations are performed. This may be broken to confirm that it is in use. Furthermore, a lock mechanism that cannot be disengaged unless a replacement warning is issued may be used.

Particularly effective ones are shown in FIG.
In FIG. 14, the recording chip IJH and the ink tank I
Each JT is made to carry its own information, and these are properly discriminated using individual electric transmission paths, and the driving conditions are appropriately changed. The tank information TM has a rank to be mounted on the recording chip IJH as data by an electric signal or a different arrangement of electric contacts or a resistance value. The tank information TM is preferably a ROM having the driving condition itself. The tank information TM passes through the signal terminal T1 of the recording chip IJH and the terminal T3 of the carriage IJC, and the control means C.
To C. Then, the control unit CC determines whether or not the ink tank IJT is attached to the recording chip IJH and the ink tank to which the ink tank IJT is applied, based on the determination table stored in the tank determination table TT. If the control unit CC has previously selected the ink tank information to be mounted when the ink tank is replaced, the suitability thereof can be determined only by comparing the transmitted ink tank information with the selected information. If the transmitted ink tank information is proper, the control means CC adopts the information.

The head information HM (information is preferably a writable memory and the number of ink tanks used is included in the recording chip IJH, which includes information on manufacturing driving conditions and whether the recording chip is in use or new. (Writable configuration is good), via the terminal T2 of the carriage IJC,
It reaches the control means CC. Then, the control unit CC discriminates the information provided in the recording chip IJH based on the discrimination table stored in the head discrimination table HT. The control means CC selects the optimum drive condition for the electrothermal converter H of the recording chip being used from the drive condition table DT based on the ink tank information and this head information. Then, the control unit CC controls the head drive unit HD so as to drive the recording chip IJT under the selected optimum drive condition.

As described above, various kinds of determination can be applied to each part of the present invention, and the present invention includes all the above-mentioned configurations.

The present invention is particularly applicable to the ink jet recording methods, such as US Pat. Nos. 4,723,129 and 4th.
What is done using the basic principles disclosed in 740,796 is preferred. This method can be applied to both the so-called on-demand type and the continuous type. In particular, in the case of the on-demand type, it is arranged corresponding to the sheet or liquid path holding the liquid (ink). By applying at least one drive signal to the electrothermal converter, which corresponds to the recorded information and causes a rapid temperature rise exceeding nucleate boiling, thermal energy is generated in the electrothermal converter, This is effective because the film is boiled on the heat-acting surface, and as a result, bubbles in the liquid (ink) can be formed in one-to-one correspondence with the drive signal.

As the constitution of the recording head, in addition to the combination constitution of the ejection port, the liquid passage, and the electrothermal converter (the linear liquid passage or the right-angled liquid passage) as disclosed in the above-mentioned specifications, US Pat. No. 4,558,333 and US Pat. No. 4, which disclose a configuration in which a heat acting portion is arranged in a bending region.
The structure using the specification of 459600 is also included in the present invention.

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 is obtained by combining a plurality of recording heads as disclosed in the above-mentioned specification. Either of the constitution satisfying the above condition or the constitution as one recording head integrally formed may be used, but the present invention can exert the above-mentioned effects more effectively.

Capping means for the recording head,
It is also stable to perform cleaning means, pressurizing or suctioning means, electrothermal converter or other heating element or preheating means by a combination thereof, and preparatory ejection mode in which ejection other than recording is performed. Useful for recording.

[0070]

According to the present invention, relatively stable recording can be performed and ink consumption efficiency can be improved without being affected by replacement of the ink tank for re-ink supply or re-supply itself, and the recording head as a whole can be obtained. The life of can be extended. For example, even if the ink tank is replaced during recording, it is possible to prevent image change that would occur in one page, and if the ink tank is replaced while recording a large number of identical images, the same images are unified. Achieve multiple records.

[Brief description of drawings]

FIG. 1 is a flow chart in the case of changing a set temperature for temperature control of the present invention.

FIG. 2 is a flow chart for color recording in which the remaining amount detection mechanism of the present invention is used for ink tank replacement and PWM control is performed.

FIG. 3 is a flowchart of a case where a voltage (solid lines 101 and 102) exceeding the minimum drive voltage V _sh of the present invention is increased stepwise and supplied.

FIG. 4 is an ink jet recording apparatus I to which the present invention can be applied.
It is a general view of JRA.

FIG. 5 is a cross-sectional view of a main part including a carriage on which a recording chip used for carrying out the present invention is mounted.

FIG. 6 shows changes in the ink discharge amount and the drive minimum voltage when printing is completed on one recording chip.

FIG. 7 is a principle diagram of correction in the case of guaranteeing the minimum ejection amount and suppressing fluctuations in the ejection amount.

FIG. 8 is a diagram illustrating a principle of correction in the case of suppressing the fluctuation of the ejection amount to a minimum.

FIG. 9 is a principle diagram of a drive voltage correction for changing the drive voltage to delay the unstable / incapable discharge timing.

FIG. 10 is an explanatory diagram when an ink tank having an ink holding portion that generates a negative pressure is used in the ink tank.

FIG. 11 is a diagram showing an example of ejection amount control when a recording chip is driven by divided pulses.

FIG. 12 is a diagram for explaining a divided pulse relating to an example described later.

FIG. 13 is a discharge amount Vd [pl / drop] according to FIG.
FIG. 9 is a diagram for explaining the relationship between the prepulse width P1 [μsec] and the prepulse width.

FIG. 14 is an explanatory diagram of a configuration for detecting or determining a new mounting state of an ink tank of a recording chip and a recording chip.

[Explanation of symbols]

 IJT ink tank IJH recording chip TM tank information T1 signal terminal T2 terminal T3 terminal CC control means TT tank discrimination table TT H electrothermal converter HM chip information IJC carriage HT chip discrimination table HD chip drive means DT drive condition table

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor, Mr. Iwasaki, 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor, Kiichiro Takahashi, 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Incorporated (72) Inventor Shigetasu Nagoshi 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (10)

[Claims] 1. An ink jet recording apparatus for performing recording using a recording head for recording in a state where a recording chip having an ink ejecting section and an ink tank containing ink are integrated, wherein the recording head is provided with respect to the recording chip. Ink jet recording, characterized in that a plurality of ink tanks can be exchanged and used, and a means for changing drive conditions of the recording head according to the number of times the ink tank is used for one recording chip is provided. apparatus. 2. The ink jet recording apparatus according to claim 1, wherein the changing unit has a mechanism that corrects a driving condition of the mounted recording head in response to replacement of the recording chip with respect to the apparatus. Recording device. 3. The recording head comprises a plurality of ejection ports as the ink ejection portion and an electrothermal converter that generates thermal energy corresponding to each ejection port to form bubbles in the ink. The inkjet recording apparatus according to claim 1 or 2, further comprising means for supplying a drive signal for driving the electrothermal converter according to the recording signal. 4. An ink recording method for recording by supplying ink to a recording chip having an ink ejecting section by using an ink tank, wherein the recording is performed according to the number of times of ink supply from the ink tank to the recording chip. An ink recording method characterized in that recording is performed by changing driving conditions for ink ejection of a chip. 5. The recording chip has a service life applicable to N ink tanks, and the ink ejection drive condition is changed so as to decrease the ejection amount according to the increase of N. 5. The ink recording method according to claim 4, wherein the recording chip discharges ink uniformly. 6. The drive condition for ejecting ink is a drive signal through a preheating signal and an air bubble forming main signal supplied to an electrothermal converter of an ink ejecting section in response to a recording signal, The ink recording method according to claim 4, wherein the change lowers the supply energy of the preheating signal according to the number of times of ink supply. 7. The ink ejection drive condition is a setting reference for adjusting the temperature of the recording chip or the ink, and the change is to lower the setting reference according to the number of times of ink supply. Ink recording method described. 8. The recording chip comprises a plurality of ejection ports as the ink ejection section and an electrothermal converter that generates thermal energy corresponding to each ejection port to form bubbles in the ink. 8. The ink recording method according to claim 4, wherein a drive signal for driving the electrothermal converter is supplied in accordance with the signal to eject the ink. 9. An ink recording method for recording by supplying ink to a recording chip having an ink ejecting section using an ink tank, the number of times of ink supply to the recording chip by the ink tank, and the mounted ink. An ink recording method, wherein recording is performed by changing a driving condition for ink ejection of the recording chip according to an ink consumption rate in a tank. 10. The recording chip is provided with a plurality of ejection ports as the ink ejection section and an electrothermal converter that generates thermal energy corresponding to each ejection port to form bubbles in the ink. The ink recording method according to claim 9, wherein a drive signal for driving the electrothermal converter is supplied in accordance with the signal to eject the ink.