JP2002127454A - Method of detecting amount of residual ink and recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method of accurately detecting a desired amount of residual ink and an ink jet type recorder using the above method. SOLUTION: The recorder has a function of detecting a residual amount using both of a sensor method and a dot-counting method. When it is judged that the amount of residual ink in a space where raw ink in an ink tank is out by using an optical means having a light emitting element and a light receiving element, an amount of ink per one time of ejection is calculated at that time and then the number of times of available ejections after that is estimated based on the calculated value and the amount of ink included in an ink absorption body. After that, the number of times of ejections of ink at a time when the recording operation is performed by supplying ink from the ink absorption body is counted and then the presence or absence of the residual ink in the ink tank is judged based on the counted value, the number of times of available ejections and a predetermined threshold.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and apparatus for detecting the remaining amount of ink, and more particularly, to a method for detecting the remaining amount of ink in an ink tank for supplying ink to a recording head which performs recording in accordance with an ink jet system and recording using the method. Related to the device.

[0002]

2. Description of the Related Art The function of detecting the remaining amount of ink in an ink jet recording apparatus has the effect of preventing a defective ink ejection caused by performing a recording operation without ink. According to this function, the remaining amount of ink in the ink tank is detected and the remaining amount is displayed, or
When the remaining amount decreases, a warning can be issued to the apparatus user or the recording operation can be stopped.

Various methods have been proposed and implemented for specifically detecting the remaining amount of ink in an ink tank.

As one of the methods, there is a method in which a sensor is provided in an ink tank to directly measure the remaining amount of ink. When two electrodes in contact with the ink are used for the ink tank as the sensor, the remaining amount of the ink is estimated by measuring the resistance value between the electrodes that changes according to the remaining amount of the ink. When an optical sensor is provided in the vicinity of the ink tank, light is incident on the ink in the ink tank, and the reflected light or transmitted light that changes according to the remaining amount of ink and the presence or absence of ink is used by the optical sensor. It detects the remaining amount of ink and the presence or absence. Such an ink remaining amount detection method is called a “sensor method”.

Another method is to indirectly estimate the amount of ink consumption by counting the number of ink droplet ejections and multiplying the number of ink droplets per ejection, which is estimated in advance. This method is called "dot counting method".
is called.

[0006]

However, the above conventional example has the following problems.

First, the problem of the sensor method will be described.

Usually, an ink tank has a negative pressure generating mechanism such as an ink absorber or an ink bag in order to stabilize ink ejection, and there is a mechanical restriction.

For example, when an electrode is installed in an ink tank, the absorber may be pressed to affect the negative pressure generating mechanism itself, or a contact is provided outside the ink tank to avoid the pressure. In this case, there is a problem that it is difficult to secure the sealing performance of the ink bag.

When an optical sensor is provided, a transparent portion is required in the ink tank because light from a light source enters the ink tank and transmitted light or reflected light comes out of the ink tank. However, since the ink absorber has a problem that light does not pass therethrough, the position where the optical sensor is installed is limited, so that it is possible to avoid leaving too much ink in the ink tank and to obtain a desired ink remaining amount. It is difficult to install a sensor so that detection can be performed by using the sensor.

Next, a dot counting method will be described.

The amount of ink per discharge from the nozzles of the recording head varies from device to device, and the amount of ink discharged varies depending on the environmental temperature and humidity of the device. Considering all factors such as variations among devices and the environment, the variation reaches about 40% of the total ink amount. Therefore, it is necessary to use the ink to perform a warning or stop the recording operation before the ink runs out. Nearly half must be left in the ink tank. Leaving too much ink in this way loses the meaning of the ink remaining amount detection itself.

Further, according to the dot counting method, it is necessary to reset the number of ejections counted up to now when an ink tank is newly installed. If the user forgets this, the remaining amount detection function is activated. There is also the problem of disappearing.

SUMMARY OF THE INVENTION The present invention has been made in view of the above conventional example, and provides an ink remaining amount detecting method capable of detecting an accurate and desired remaining ink amount, and a recording apparatus according to an ink jet system using the method. It is an object.

[0015]

To achieve the above object, a method for detecting the remaining amount of ink according to the present invention comprises the following steps.

That is, an ink having a first space for accommodating ink and a second space for accommodating an ink absorber having absorbed the ink to be supplied to a recording head which performs recording in accordance with an ink jet system. An ink remaining amount detecting method for detecting an ink remaining amount in a tank, wherein a counting step of counting the number of times of ink ejection from the recording head, a light incident on the first space, and a reflected light of the light Alternatively, the transmitted light is detected, and the first light is detected based on the detected light.
A discriminating step of discriminating the presence or absence of remaining ink in the space, an accumulating step of accumulating the number of ink ejections counted in the counting step until it is judged that there is no remaining ink in the discriminating step, A calculating step of calculating an ink discharge amount per one discharge based on a predetermined amount of ink accommodated in the space and the number of times of ink discharge integrated in the integrating step; An estimating step of estimating the number of ink discharges that can be performed based on the ink amount and the amount of ink per one discharge calculated in the calculating step; an estimable number of ink discharges and the number of ink discharges estimated in the estimating step A determination step of determining whether there is remaining ink in the ink tank based on the number of ink ejections in a printing operation after the acquisition of Comprising an ink remaining amount detection method.

Further, it is preferable that the method further comprises a display step of displaying a warning message on a display screen when it is determined in the determining step that there is no remaining ink in the ink tank.

Further, after the warning message is displayed in the display step, the determination step is executed again, and according to the determination result obtained by the execution again,
It is preferable to include an ink tank replacement determining step of determining whether the ink tank has been replaced with a new ink tank filled with ink.

Further, in the ink tank replacement determining step, when it is determined that the ink tank has been replaced, a reset step of resetting the accumulated number of times of ink tank discharge to zero may be provided.

According to another aspect of the present invention, there is provided a recording head for performing recording in accordance with an ink jet method, a first space for accommodating ink to be supplied to the recording head, and an ink absorber for accommodating the ink. An ink tank having two spaces, a counting means for counting the number of times of ink ejection from the recording head, a light emitting element for irradiating the first space with light, and a reflected light or transmitted light of the light. Optical means having a light receiving element for receiving light; determining means for determining the presence or absence of remaining ink in the first space based on the amount of light received by the light receiving element; An integrating means for integrating the number of ink ejections counted by the counting means until it is determined that there is no ink; a predetermined amount of ink stored in the first space; Therefore, based on the accumulated number of times of ink ejection, a calculating means for calculating the amount of ink discharged per one time, and the amount of ink absorbed by the ink absorber and the amount of ink per one time calculated by the calculating means are calculated. Estimating means for estimating the number of ink discharges possible based on the amount of ink discharge; and estimating the number of ink discharges estimated by the estimating means and the number of ink discharges in the printing operation after the number of ink discharges is obtained. A determination unit for determining whether there is remaining ink in the ink tank.

If the determination means determines that there is no remaining ink in the ink tank, a warning message or a remaining ink amount is displayed on a display screen.
For example, it is preferable to provide display means including an LCD or the like.

Further, after the warning message is displayed by the display means, the determination means is executed again, and according to the determination result obtained by the execution again,
It is preferable to include an ink tank replacement determining unit that determines whether the ink tank has been replaced with a new ink tank filled with ink.

Further, it is preferable to provide a reset means for resetting the accumulated number of times of ink tank discharge to zero when the ink tank replacement determining means determines that the ink tank has been replaced.

The determining means includes a subtracting means for subtracting the number of ink ejections obtained at each printing operation after the number of ink ejections is obtained from the number of ink ejections possible, or a subtracting means for obtaining the number of inks. It is desirable to include a comparing means for comparing the obtained value with a predetermined threshold.

Further, it is preferable that the apparatus further comprises a recording control means for controlling to stop the recording operation by the recording head when the determination means determines that there is no remaining ink in the ink tank.

The recording head desirably includes an electrothermal converter for generating thermal energy to be applied to the ink in order to discharge the ink using thermal energy.

As described above, in the present invention, the remaining amount detection function of both the sensor system and the dot counting system is introduced, and the remaining space in the first space of the ink tank is formed by using optical means having a light emitting element and a light receiving element. When it is determined that the amount of ink has run out, the operation is performed so as to determine the presence or absence of remaining ink in the ink tank by counting the number of times of ink ejection.

Then, in counting the number of times of ink ejection, 1 is obtained by the recording apparatus or the ink tank.
Based on the amount of ink per discharge, the count is performed to determine whether or not there is ink remaining in the final ink tank.

[0029]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of the present invention will be described below in detail with reference to the accompanying drawings.

<Principle of Remaining Ink Detection (FIGS. 1 and 2)>
FIG. 1 is a diagram illustrating the principle of detecting the remaining amount of ink in an ink tank using a sensor, particularly an optical sensor. In practice, a basic configuration for detecting the remaining amount of ink as shown in FIG. 1 is provided in the ink jet recording apparatus.

First, in FIG. 1, reference numeral 101 denotes an ink tank made of a light-transmitting material such as transparent plastic for accommodating ink to be supplied to the recording head, and 102 supplies the recording head from the ink tank 1 with the ink. 103 is an air communication port for performing gas-liquid exchange accompanying ink consumption, and 104 is an ink of black, cyan, magenta, yellow, or other color commonly used in a color printer.
Reference numeral 05 denotes an ink absorber made of polyurethane or the like having an appropriate capillary force so as to generate an appropriate negative pressure in the ink tank in order to stably supply ink for printing by the print head. Is held at an appropriate position in the ink tank (the left half space in FIG. 1), and 107 is ink not absorbed by the ink absorber 105 (hereinafter referred to as “raw ink”).

The lower part of the partition plate 106 communicates with the space in the right half and the space in the left half of the ink tank 101. In this manner, the raw ink 10
By supplying 7 to the ink absorber 105, the negative pressure is kept constant while the raw ink 107 remains.

An LED 108 serves as a light source for detecting the presence or absence of the raw ink 7. As the LED, an LED that emits light having a wavelength of 555 nm that hardly transmits any of the four color inks of black, cyan, magenta, and yellow, for example, HBG5066X manufactured by Stanley Electric Co., Ltd. can be used. Reference numeral 109 denotes a photodetector such as a silicon photodetector having sufficient sensitivity to the wavelength of the light from the LED 108. As shown in FIG. 1 and the raw ink 7.

The light emission control of the LED 108 and the processing based on the light detected by the light detector 109 are performed by a CPU or the like provided in the ink jet recording apparatus.

Basically, when the above configuration is provided in the ink jet recording apparatus, the detection of the remaining amount of ink in the ink tank is executed according to the sequence shown in the flowchart of FIG.

First, in step S100, when the recording head to which ink is supplied from the ink tank 101 discharges ink, in the next step S110, the LED 10
Light is irradiated from step 8 and the light is received by the photodetector 109. In step S120, it is checked whether the amount of received light is zero.

Here, in the first stage, the ink tank 10
1 is filled with the raw ink 107, LED1
08 is absorbed by the ink and the photodetector 1
The output of the switch 09 is “zero” except for the offset and the background that causes noise, and the process returns to step S100. On the other hand, as the printing operation progresses, the ink is consumed and the raw ink 107 gradually decreases.
08 arrives and a non-zero output is obtained at the photodetector 109. Thus, upon receiving the output change of the photodetector 109, the CPU determines that the raw ink 107 has run out, and the process proceeds to step S130.

In step S130, the CPU first initializes the count value (DCNT) to "0" in order to start counting the number of ink ejections.
If ink ejection occurs at 140, step S1
At 50, the number of times of ink ejection is counted and added. Then, in step S160, the count value (D
CNT) has reached a predetermined value (TH),
If DCNT <TH, it is determined that there is ink remaining to continue the printing operation, and the process returns to step S140. However, if DCNT ≧ TH, it is determined that the remaining amount of ink is small, and the process returns to step S170. move on.

Finally, in step S170, the CPU displays a warning message indicating that the remaining amount of ink is low on an operation panel or the like provided in the recording apparatus. The user sees the warning message and replaces the ink tank with a new one or prepares a new one.

In this case, the number of ink ejections corresponding to the amount of ink supplied from the ink absorbed by the ink absorber 105 is counted. Than quantity
Since it depends on the porosity, the compression ratio, and the like of the ink absorber 105, the variation in the amount of ink can be suppressed to some extent after a certain manufacturing process.

Since the amount of ink absorbed by the ink absorber 105 is 1/5 to 1/2 of the amount of ink contained in the entire ink tank 101, it is necessary to detect the remaining amount of ink according to the dot counting method. Can be reduced in proportion to the ratio. As a result, the total error can be suppressed to 1/10 to 1/4 of the error in the conventional example, that is, 4 to 10% of the total ink amount.

In the example shown in FIG.
The optical path from to the photodetector 109 is a straight line, and a transmissive sensor that uses the photodetector 109 to detect light transmitted through the ink in the ink tank is used. It is sufficient if there is a sufficient difference in the light amount level detected by the photodetector 109 between when there is ink in the ink tank and when there is no ink in the ink tank.
09 on the same side of the ink tank, irradiates light to the bottom of the ink tank made of a light transmissive material, and receives light reflected by the bottom and returning to the photodetector 109 again. A reflection type sensor configured to detect the remaining amount may be used.

FIG. 3 is a partial cutaway view showing a configuration around an ink tank in a recording apparatus for detecting the remaining amount of ink using a reflection type sensor.

In FIG. 3, reference numeral 110 denotes a bottom surface of the ink tank 101 serving as a light reflecting surface, and 111 denotes an infrared LED 108 '.
An optical conduit through which the light emitted from the reflective photointerrupter and the light reflected from the bottom surface 110 are paired.
Reference numeral 13 denotes a carriage of the recording apparatus on which the ink tank 101 is mounted, 114 denotes a carriage arm that holds the carriage 113, and 115a and 115b denote guide rails that assist the carriage 113 to reciprocate in a direction perpendicular to the plane of the drawing.

As can be seen from the configuration of FIG.
Is located below the position where the ink absorber 105 is provided. Accordingly, the reflection type photo interrupter detects the density of the ink absorber 105.

In such a configuration, the ink absorber 1
In the case where ink is contained in the liquid crystal 05 and the density of the ink absorber 105 is high, the light emitted from the infrared LED 108 'is absorbed by the ink, and the photodetector 109' hardly emits light other than the background light. Cannot be detected and its output is low. On the other hand, when the ink is consumed and there is no ink in the ink absorber 105, the light is not absorbed by the ink but is reflected by the bottom of the ink tank, and the reflected light is detected by the photodetector 109 '. The output will be higher. Thus, when there is ink and when there is no ink, the photodetector 10
9 ', there is a difference between the outputs.
U determines the presence or absence of ink.

As described above, by using the reflection type sensor, it is possible to determine whether or not ink is present in the ink absorber, so that it is possible to detect the remaining amount of ink in a place where the remaining amount of ink in the ink tank becomes smaller. Become. Therefore, if the variation in detection at this position is small, more accurate remaining amount detection becomes possible.

<Configuration of Inkjet Recording Apparatus (FIGS.
FIG. 6)> FIG. 4 is a perspective view showing a schematic configuration of a recording apparatus provided with a recording head which performs recording according to an ink jet system, which is a typical embodiment of the present invention. In this embodiment, as shown in FIG. 4, the recording head 1 is connected to an ink tank 7 for supplying ink to the recording head 1 and integrally forms an ink cartridge 20. In this embodiment, the ink cartridge 20 has a configuration in which the recording head 1 and the ink tank 7 can be separated as described later, but an ink cartridge in which the recording head and the ink tank are integrated may be used. .

The bottom surface of the ink tank 7 is provided with a light reflecting surface for detecting the remaining amount of ink, and the internal structure of the ink tank 7 has a structure as shown in FIG. 1 or FIG. ing. Accordingly, hereinafter, when referring to the internal structure of the ink tank 7, the reference numerals used in FIG. 1 or FIG. 3 will be used.

Further, the recording head is provided with a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as energy used for discharging ink, particularly in an ink jet recording system. By using a method in which a change in the state of the ink is caused by the thermal energy, higher density and higher definition of recording are achieved.

In FIG. 4, a recording head 1 is mounted on a carriage 2 in a posture for ejecting ink downward in the drawing, and ejects ink droplets while moving the carriage 2 along a guide shaft 3 to form recording paper. An image is formed on a recording medium (not shown) as described above. The carriage 2 is moved left and right (reciprocated) via the timing belt 5 by the rotation of the carriage motor 4. An engagement claw 6 is provided on the carriage 2 and engages with an engagement hole 7a of the ink tank to fix the ink tank 7 to the carriage 2.
When printing for one scan of the print head is completed, the printing operation is interrupted, the printing medium located on the platen 8 is conveyed by a predetermined amount by driving the feed motor 9, and then the carriage 2 is moved along the guide shaft 3 again. To form an image for the next one scan.

On the right side of the apparatus main body, a recovery device 1 for performing a recovery operation for keeping the ink discharge state of the recording head 1 good.
The apparatus 10 includes a cap 11 for capping the recording head 1, a wiper 12 for wiping the ink ejection surface of the recording head 1, and a device for sucking ink from the ink ejection nozzles of the recording head 1. A suction pump (not shown) and the like are provided.

The driving force of the feed motor 9 for conveying the recording medium is transmitted to the original recording medium conveying mechanism and also to the automatic paper feeder (ASF) 13.

Further, on the side of the recovery device 10, an infrared LE
An optical unit 14 that constitutes a reflective sensor for detecting the remaining amount of ink, which includes a D (light emitting element) 15 and a phototransistor (light receiving element) 16, is provided. The light-emitting element 15 and the light-receiving element 16 are mounted so as to be arranged along the recording paper conveyance direction (the direction of arrow F). The optical unit 14 is attached to a chassis 17 of the apparatus main body. When the ink cartridge 20 is mounted on the carriage 2 and moves rightward from the position shown in FIG.
4 above. Then, the state of the ink can be detected from the bottom surface of the ink tank 7 by the optical unit 14 (details will be described later).

In this embodiment, a reflection type sensor is used for detecting the remaining amount of ink. However, it is assumed that light from the sensor irradiates a space of the ink tank containing the raw ink.

Next, a control configuration for executing the recording control of the above-described apparatus will be described.

FIG. 5 is a block diagram showing the configuration of the control circuit of the printing apparatus. In FIG. 5 showing the control circuit, 170
0 is an interface for inputting a recording signal, 1701 is M
A PU 1702 is a ROM for storing a control program executed by the MPU 1701, and a 1703 is a DRAM for storing various data (such as the print signal and print data supplied to the print head 1). A gate array (G.1704) controls supply of print data to the print head 1.
A. ), The interface 1700, the MPU 170
1. Data transfer control between the RAMs 1703 is also performed. 170
5 is a head dryer for driving the recording head 1, 170
Reference numerals 6 and 1707 denote motor drivers for driving the feed motor 9 and the carriage motor 4, respectively.

The operation of the above control structure will be described. When a recording signal is input to the interface 1700, the gate array 17
04 and the MPU 1701 converts the recording signal into recording data for printing. Then, the motor driver 17
06 and 1707 are driven, and the head driver 1
The recording head 1 is driven according to the recording data sent to 705, and recording is performed.

Reference numeral 1710 denotes an LCD 1711 for displaying various messages relating to the printing operation and the wiping state of the printing apparatus, and LEDs of various colors for notifying the printing operation and the state of the printing apparatus.
The display unit includes a lamp 1712 and a buzzer (not shown) that emits a warning sound.

Further, an ink remaining amount detecting section 25 for detecting the presence or absence of ink in the ink tank 7 integrated with the recording head 1.
Is controlled by the MPU 1701.

FIG. 6 is a block diagram showing a detailed configuration of the ink remaining amount detecting section 25.

In the configuration shown in FIG.
Based on the control signal from the PU 1701, the controller 32 outputs a pulse signal having a predetermined duty (DUTY) ratio (%) to the LED drive circuit 30, and the light emitting element 15 configuring the optical unit 14 according to the duty ratio.
To irradiate the bottom of the ink tank 7 with infrared light.

The infrared light is reflected on the reflection surface at the bottom of the ink tank 7 and returns to the light receiving element 16 constituting the optical unit 14. The light receiving element 16 as a phototransistor converts the received infrared light into an electric signal, and outputs the electric signal to a low-pass filter (LPF) 31. The low-pass filter (LPF) 31 cuts high-frequency noise out of the electric signal input from the light receiving element 16 and sends only a signal with a low frequency to the controller 32. Controller 3
A / D conversion 2 converts the signal of the low-pass filter (LPF) 31 into a digital signal. Then, the converted value is transferred to MPU 1701.

As shown in FIG. 6B, the light emitting element 15 is an infrared LED that emits infrared light 28,
The light receiving element 16 is a phototransistor that receives the infrared light 29 and outputs an electric signal according to the intensity of the received light.
These infrared LEDs and phototransistors are arranged so as to be arranged along the recording paper transport direction as shown in FIG.

<Remaining Ink Detecting Process (FIG. 7)> The remaining ink detecting process according to this embodiment will be described with reference to the flowchart shown in FIG. Note that, in the processing steps shown in FIG. 7, the same processing steps as those shown in FIG. 2 are denoted by the same reference numerals, and description thereof will be omitted.

In this embodiment, the MPU 1701 starts counting the number of ink ejections immediately after the ink tank 7 is newly mounted on the recording apparatus. Therefore, in step S95, the count value (DCNT) is set to "0" and initialized. At this point, the output of the light receiving element 16 is zero as described above.

Next, according to the recording operation, step S10
The process of 0 to S120 is executed. At this time, in step S105, after the ink ejection operation in step S100, the number of ink ejections is counted, and the counted number is added to the count value (DCNT).

When the ink is consumed and the raw ink 107 runs out in the ink tank 7 as the printing operation proceeds, the output of the light receiving element 16 changes, and if the MPU 1701 determines that the raw ink 107 has run out, the processing is terminated. Proceed to step S125.

Raw ink 10 filled in ink tank 7
7 can be known from the volume of the ink storage unit 112, and in step S125, the amount of the raw ink 107 is divided by the number of ink ejections (DCNT) obtained by counting and adding up to that point, and Is calculated (p = raw ink amount / DCNT).

Next, since the amount of ink that can be held by the ink absorber can be known from the volume of the ink absorber 105 and the porosity thereof, in step S135, the ink absorption is calculated using the calculated value of (p). Estimate how many more discharges can be made using the ink absorbed in the body 105 (the number of possible discharges in the future (PDIS) = absorber ink amount / p)
).

Thereafter, every time ink ejection occurs due to the recording operation in step S140, the process proceeds to step S15.
In 5, the number of ejections generated in step S140 is subtracted from the possible number of ejections (PDIS). Then, in step S165, the value of the PDIS obtained in step S155 is compared with a predetermined threshold (PTH). Here, if PDIS> PTH, the process proceeds to step S14.
However, if PDIS ≦ PTH, the process proceeds to step S170.

Therefore, according to the above-described embodiment, when the raw ink is exhausted, the number of discharges that can be performed in the future is estimated based on the number of discharges up to that time. Therefore, the estimation includes the characteristics of the apparatus itself and the installation environment. Therefore, it is possible to eliminate an error caused by an individual difference between the recording apparatuses and an environment, which cannot be eliminated by the conventional method. In this case, the remaining error factors are substantially only the ink capacity in the ink tank and the ink absorber, so that the total error can be suppressed to a smaller value.

Although the above description has not described the processing after ink tank replacement, the processing after replacement with a new ink tank is replaced by the processing shown in FIG. 7 and the steps S180 to S200 shown in the flowchart of FIG. What is necessary is just to add processing of.

That is, after the warning process in step S170, in step S180, light is emitted from the light emitting element 15 and the light is received by the light receiving element 16. Further, in step S190, whether or not the amount of received light is “zero” is determined. Find out. Here, when a new ink tank filled with ink is mounted, the light receiving element 16 should have returned to “zero”. Therefore, the amount of received light is “zero”
If so, the process proceeds to step S200, assuming that a new ink tank has been installed, and further returns to step S95, where the count value (DCNT) of the number of times of ink ejection that has been counted and added so far is calculated. “0”
Reset to. On the other hand, if the amount of received light is not “zero”, it is considered that a new ink tank has not been replaced, and the process returns to step S180.

By doing so, the count value (DCNT) of the number of times of ink ejection can be automatically reset, and the detection of the remaining amount of ink can be continued.

In the warning display processing in step S170, control may be performed so as to stop the printing operation in order to ensure that no printing failure is generated, or to respond to the estimated value of the remaining ink amount. The displayed remaining amount may be displayed on the LCD. By doing so, more detailed ink remaining amount information can be given to the user.

The calculated value of the average ink amount (p) per discharge varies depending on the following factors.

That is, variations in the discharge amount due to physical factors such as the nozzles of the print head, variations in the discharge amount due to control factors such as ink discharge control / recovery operation, variations in the ink consumption other than during printing, and the surroundings of the installed printing apparatus. Are the ink ejection amount variation and the ink evaporation amount variation due to environmental factors such as temperature and humidity, and the amounts and ratios of the ink amounts contained in the ink storage unit 112 and the ink absorber 105 for storing the raw ink in the ink tank.

Among them, the term “unique” is specific to the apparatus, and the term is constant unless the place where the apparatus is installed changes.
Therefore, although the installation location of the device has not been moved,
If the value of “p” has changed, it is considered that is the main cause of the error here. Therefore, it is considered that the conventional value is closer to the correct value than the new value as the value of “p”.

Next, the value of “p” changes due to the factor when the installation location is moved, but there is still a factor. It is desirable to gradually change the value of p by using an intermediate value between the values of.

An embodiment for realizing these will be described below.

First, several ranks are set as the value of p so that they can be classified into any of them. In addition, the value of p can be stored in the memory. When p is classified into a newly calculated rank, the stored p
Compare with rank. Here, when the new rank value is m, and the stored rank value is n, if m <n, a value larger than m and smaller than n. If m = n, mm if m> n, a value smaller than m and larger than n. Newly memorized.

In this way, the influence of the above-described error can be minimized. Further, by performing the rank value processing, the calculation is omitted, and high-speed processing becomes possible.
Although the above-described embodiment has been described using an example using an optical sensor, the presence / absence of raw ink in the ink storage unit may be detected by another conventionally known method such as detection using an electrode. Which type of detection system should be adopted should be determined from the overall viewpoint such as performance and cost of the system of the inkjet recording apparatus. By adopting the optimal method, the effect of the present invention can be maximized, or the cost can be reduced even with the same effect.

For example, if the ink tank is already provided with a conductor that communicates with the ink, the use of an electrode type detection system can reduce the cost more than providing a new optical detection system. .

In the above embodiment, the description has been made assuming that the droplets ejected from the recording head are ink, and that the liquid contained in the ink tank is ink. It is not limited. For example, an ink tank may contain a processing liquid discharged to a recording medium in order to improve the fixability and water resistance of the recorded image or to improve the image quality.

The above-described embodiment is particularly provided with a means (for example, an electrothermal converter or a laser beam) for generating thermal energy as energy used for performing ink ejection even in an ink jet recording system. By using a method in which a change in the state of the ink is caused by energy, it is possible to achieve higher density and higher definition of recording.

The typical configuration and principle are described, for example, in US Pat. Nos. 4,723,129 and 4,740.
It is preferable to use the basic principle disclosed in the specification of Japanese Patent No. 796. This method can be applied to both the so-called on-demand type and continuous type. In particular, in the case of the on-demand type, liquid (ink)
By applying at least one drive signal corresponding to the recorded information and providing a rapid temperature rise exceeding the nucleate boiling to the electrothermal transducer arranged corresponding to the sheet or the liquid path in which Since thermal energy is generated in the electrothermal transducer and film boiling occurs on the heat-acting surface of the recording head, bubbles in the liquid (ink) corresponding to this drive signal on a one-to-one basis can be formed. It is valid. By discharging the liquid (ink) through the discharge opening by the growth and contraction of the bubble, at least one droplet is formed. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of the liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable.

As the pulse-shaped driving signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. Further, if the conditions described in US Pat. No. 4,313,124 relating to the temperature rise rate of the heat acting surface are adopted, more excellent recording can be performed.

As the configuration of the recording head, in addition to the combination of a discharge port, a liquid path, and an electrothermal converter (a linear liquid flow path or a right-angled liquid flow path) as disclosed in the above-mentioned specifications, A configuration using U.S. Pat. No. 4,558,333 or U.S. Pat. No. 4,459,600, which discloses a configuration in which a heat acting surface is arranged in a bent region, is also included in the present invention. In addition, for multiple electrothermal transducers,
JP-A-59-123670 which discloses a configuration in which a common slot is used as a discharge part of an electrothermal transducer, and JP-A-59-123670 which discloses a configuration in which an opening for absorbing a pressure wave of thermal energy corresponds to a discharge part. A configuration based on 138461 may be adopted.

Further, as a full-line type recording head having a length corresponding to the width of the maximum recording medium that can be recorded by the recording apparatus, the length is determined by combining a plurality of recording heads as disclosed in the above-mentioned specification. This may be either a configuration satisfying the above requirements or a configuration as a single recording head formed integrally.

In addition to the cartridge type recording head in which an ink tank is provided integrally with the recording head itself described in the above embodiment, the recording head is electrically connected to the apparatus main body by being mounted on the apparatus main body. A replaceable chip-type recording head, which enables a simple connection and supply of ink from the apparatus main body, may be used.

It is preferable to add recovery means for the print head, preliminary auxiliary means, and the like to the configuration of the printing apparatus described above, since the printing operation can be further stabilized. Specific examples thereof include capping means for the recording head, cleaning means, pressurizing or suction means, preheating means using an electrothermal transducer or another heating element or a combination thereof. It is also effective to provide a preliminary ejection mode for performing ejection that is different from printing, in order to perform stable printing.

Further, the recording mode of the recording apparatus is not limited to the recording mode of only the mainstream color such as black, but may be a single recording head or a combination of a plurality of recording heads. Alternatively, the apparatus may be provided with at least one of full colors by color mixture.

In the above-described embodiment, the description has been made on the assumption that the ink is a liquid. However, even if the ink solidifies at room temperature or lower, the ink that softens or liquefies at room temperature is used. Or, in the ink jet method, generally, the temperature of the ink itself is controlled within a range of 30 ° C. or more and 70 ° C. or less to control the temperature so that the viscosity of the ink is in a stable ejection range.
It is sufficient that the ink is in a liquid state when the use recording signal is applied.

In addition, in order to positively prevent the temperature rise due to thermal energy as energy for changing the state of the ink from a solid state to a liquid state, the temperature can be positively prevented.
Alternatively, in order to prevent evaporation of the ink, an ink which solidifies in a standing state and liquefies by heating may be used. In any case, the application of heat energy causes the ink to be liquefied by application of the heat energy according to the recording signal and the liquid ink to be ejected, or to start to solidify when reaching the recording medium. The present invention is also applicable to a case where an ink having a property of liquefying for the first time is used. In such a case, as described in JP-A-54-56847 or JP-A-60-71260, the ink is held in a liquid state or a solid state in the concave portion or through hole of the porous sheet. It is good also as a form which opposes an electrothermal transducer. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

[0096] In addition to the above, the recording apparatus according to the present invention may be provided not only as an image output terminal of an information processing apparatus such as a computer but also integrally or separately, a copying apparatus combined with a reader or the like, and a transmission / reception apparatus. It may take the form of a facsimile machine having functions.

The present invention can be applied to a system composed of a plurality of devices (for example, a host computer, an interface device, a reader, a printer, etc.), and can be applied to a single device (for example, a copying machine, a facsimile machine). Etc.).

Further, an object of the present invention is to provide a storage medium storing a program code of software for realizing the functions of the above-described embodiments to a system or an apparatus, and a computer (or CPU) of the system or the apparatus.
And MPU) read and execute the program code stored in the storage medium.

In this case, the program code itself read from the storage medium implements the functions of the above-described embodiment, and the storage medium storing the program code constitutes the present invention.

As a storage medium for supplying the program code, for example, a floppy disk, hard disk, optical disk, magneto-optical disk, CD-ROM, CD
-R, a magnetic tape, a nonvolatile memory card, a ROM, or the like can be used.

When the computer executes the readout program codes, not only the functions of the above-described embodiment are realized, but also the OS (Operating System) running on the computer based on the instructions of the program codes. ) May perform some or all of the actual processing, and the processing may realize the functions of the above-described embodiments.

Further, after the program code read from the storage medium is written into a memory provided in a function expansion board inserted into the computer or a function expansion unit connected to the computer, based on the instruction of the program code, It goes without saying that the CPU included in the function expansion board or the function expansion unit performs part or all of the actual processing, and the processing realizes the functions of the above-described embodiments.

[0103]

As described above, according to the present invention, the detection of the remaining amount of ink having both features of the sensor method and the dot counting method is introduced, and first, the light emitting element and the light receiving element are provided. When it is determined that the remaining amount of ink in the first space of the ink tank is exhausted by using the optical unit, the presence or absence of the remaining amount of ink in the ink tank is determined by counting the number of times of ink ejection. There is an effect that it is possible to more accurately detect the remaining ink amount by compensating for the disadvantages of the above.

Further, in counting the number of times of ink ejection, 1 is obtained by the recording apparatus or the ink tank.
Based on the amount of ink per discharge, the count is performed to determine whether or not there is ink remaining in the final ink tank. Therefore, the remaining ink amount is detected in consideration of the characteristics of the recording apparatus or each individual ink tank. be able to. This allows
This reduces detection errors caused by variations in products of each individual, and contributes to more accurate detection of the remaining amount of ink.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating the principle of detecting the remaining amount of ink in an ink tank using an optical sensor.

FIG. 2 is a flowchart illustrating an outline of a remaining ink amount detection process.

FIG. 3 is a partial cutaway view illustrating a configuration around an ink tank in a recording apparatus that detects the remaining amount of ink using a reflection type sensor.

FIG. 4 is a perspective view illustrating a schematic configuration of a printing apparatus including a print head that performs printing according to an inkjet method, which is a typical embodiment of the present invention.

FIG. 5 is a block diagram illustrating a configuration of a control circuit of the printing apparatus.

FIG. 6 is a block diagram illustrating a detailed configuration of an ink remaining amount detection unit 25.

FIG. 7 is a flowchart illustrating a sequence of a process in which the accuracy of detecting the remaining amount of ink is improved.

FIG. 8 is a flowchart illustrating an ink remaining amount detection process when the ink tank is replaced with a new ink tank.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Recording head 2 Carriage 3 Guide shaft 4 Carriage motor 5 Timing belt 6 Engagement claw 7 Ink tank 8 Platen 9 Feed motor 10 Recovery device 11 Cap 12 Wiper 13 ASF 14 Optical unit 15 Light emitting element 16 Light receiving element 17 Chassis 20 Ink cartridge 30 LED drive circuit 31 Low-pass filter (LPF) 32 Controller 105 Ink absorber 1701 MPU

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroshi Taka 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (72) Inventor Shigetasu Nagoshi 3-30-2 Shimomaruko, Ota-ku, Tokyo Within Non Co., Ltd. (72) Inventor Hitoshi Sugimoto 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Masaya Uezuki 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Hitoshi Nishikori 3-30-2 Shimomaruko, Ota-ku, Tokyo F-term (reference) 2C056 EA29 EB20 EB44 EB52 EB56 EC26 FA03 FA10 KC10 KC11 KC16 KC22 KD06 2C061 AQ05 HK11 HK18 HV14HV

Claims (13)

[Claims] 1. An ink having a first space for accommodating ink and a second space for accommodating an ink absorber having absorbed the ink, so as to be supplied to a recording head which performs recording according to an ink jet system. An ink remaining amount detecting method for detecting an ink remaining amount in a tank, wherein a counting step of counting the number of times of ink ejection from the recording head; and light incident on the first space, and reflected light of the light Or a step of detecting transmitted light and determining whether there is remaining ink in the first space based on the detected light, and determining whether there is no remaining ink in the determining step. An integrating step of integrating the number of ink ejections counted in the counting step; and a predetermined amount of ink accommodated in the first space, and the number of ink ejections integrated in the integrating step. Calculating the amount of ink discharged per discharge, and calculating the amount of ink absorbed by the ink absorber and the amount of ink discharged per discharge calculated in the calculating step. An estimating step of estimating the number of times, based on the number of ink discharges estimated in the estimating step and the number of ink discharges in the printing operation after the number of ink discharges is obtained, A determination step of determining the presence or absence of the ink. 2. The apparatus according to claim 1, further comprising a display step of displaying a warning message on a display screen when it is determined in the determination step that there is no remaining ink in the ink tank. Ink remaining amount detection method. 3. After the warning message is displayed in the display step, the determination step is performed again, and according to a determination result obtained by performing the determination step again, whether the ink tank has been replaced with a new ink tank filled with ink. 3. The ink remaining amount detecting method according to claim 2, further comprising an ink tank replacement determining step of determining whether or not the ink tank is replaced. 4. The method according to claim 1, further comprising a reset step of resetting the number of times of ink tank ejection integrated in the integration step to zero when it is determined in the ink tank exchange determination step that the ink tank has been replaced. 4. The method according to claim 3, wherein the remaining amount of the ink is detected. 5. A recording head for performing recording according to an ink-jet method, a first space for containing ink to be supplied to the recording head, and a second space for containing an ink absorber absorbing the ink. Ink tank, a counting means for counting the number of times of ink ejection from the recording head, a light emitting element for irradiating the first space with light, and a light receiving element for receiving reflected light or transmitted light of the light Optical means comprising: a determining means for determining whether there is remaining ink in the first space based on the amount of light received by the light receiving element; and determining that there is no remaining ink by the determining means. An integrating means for integrating the number of times of ink ejection counted by the counting means, and a predetermined amount of ink accommodated in the first space, and Calculating means for calculating the amount of ink ejected per ejection based on the number of times of ink ejection; and calculating the amount of ink absorbed by the ink absorber and the amount of ink ejected per ejection calculated by the calculating means. Estimating means for estimating the number of ink discharges that can be performed based on the number of ink discharges estimated by the estimating means and the number of ink discharges in a printing operation after the number of ink discharges is obtained. A determining unit for determining whether there is remaining ink in the tank. 6. The display device according to claim 5, further comprising a display unit that displays a warning message on a display screen when the determination unit determines that there is no remaining ink in the ink tank. Recording device. 7. The recording apparatus according to claim 6, wherein said display means includes an LCD. 8. The ink jet recording apparatus according to claim 6, wherein said display means further displays a remaining ink amount. 9. After the warning message is displayed by the display means, the determination means is re-executed, and a new ink tank filled with ink is replaced according to a determination result by the re-execution of the determination means. The recording apparatus according to claim 6, further comprising an ink tank replacement determination unit that determines whether or not the recording medium has been replaced. 10. The image forming apparatus according to claim 1, further comprising: reset means for resetting the number of ink tank ejections integrated by said integrating means to zero when said ink tank replacement determining means determines that the ink tank has been replaced. The recording device according to claim 9, wherein: 11. The subtraction means for subtracting the number of ink ejections obtained each time a printing operation is performed after the number of ink ejections is obtained from the number of ink ejections possible; The recording apparatus according to claim 5, further comprising: a comparing unit configured to compare the obtained value with a predetermined threshold. 12. The printing apparatus according to claim 1, further comprising a printing control unit configured to stop the printing operation of the printing head when the determining unit determines that there is no remaining ink in the ink tank. The recording device according to claim 5. 13. The recording head according to claim 5, wherein the recording head includes an electrothermal converter for generating thermal energy to be applied to the ink in order to discharge the ink using thermal energy. The recording device as described in the above.