JP2960604B2 - Non-discharge detection method and ink jet recording apparatus using the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus and a method for detecting non-ejection in a recording head of the apparatus.

[0002]

2. Description of the Related Art In a recording head of an ink jet recording apparatus, for example, when the recording head is left for a long period of time without discharging.
In particular, the ink may thicken in the ink liquid passage near the ejection port, and normal ejection may not be performed. Also, when ejection is performed continuously, for example, when printing is performed with a relatively high print duty, fine bubbles generated in the ink in the liquid path with the discharge grow, and the grown bubbles are And may affect the ejection, and similarly, the normal ejection may not be performed. In addition to the air bubbles generated as described above, some of the air bubbles may be mixed into the ink in the ink supply system, such as a connection portion of the ink supply path.

[0003] In order to cope with the discharge failure due to these various causes, the ink jet recording apparatus, for example, performs a capping process for covering the discharge port surface of the recording head to prevent the ink from thickening when the discharge is not performed. Ink suction that discharges thickened ink by sucking ink from the discharge port in the capping state, or discharges ink to a predetermined ink receiver composed of an ink absorber and the like, and discharges ink in the same way as during normal recording. An ejection recovery process such as idle ejection for discharging the ink is performed.

Among the above-mentioned processes, the ejection recovery process is conventionally performed automatically at a predetermined time interval, for example, when the apparatus is turned on or during a printing operation, or a recovery button or the like is operated by an operator as necessary. It was done by pressing.

[0005]

Among the above-mentioned conventional ink jet recording apparatuses, those which always perform an ejection recovery process when the apparatus is turned on have improved reliability regarding the ejection of the recording head. In the case of using a device that repeatedly turns the power on and off frequently, the leaving time becomes relatively short, so that it is often not necessary to perform the ejection recovery process every time the power is turned on. In such a case, there is a problem that the ink is unnecessarily consumed in the ejection recovery processing.

At the same time, frequent discharge recovery processing is performed every time the power is turned on, so that the ink consumption increases and the running cost increases. In particular, in the case of a disposable head in which the recording head and the ink tank are integrated and the integral recording head and the ink tank are exchanged together when the ink is exhausted, the ink consumption increases due to the conventional ejection recovery processing. As a result, the number of times of head replacement increases and the running cost increases. The same can be said for a full-color ink jet recording apparatus using a plurality of recording heads.

On the other hand, in a configuration in which an operator operates a recovery button or the like in accordance with the determination to perform a recovery process, the recovery process is not performed automatically, so that the above-described recovery process is performed. Although the useless ink consumption is relatively small,
Conversely, recovery processing may not be performed when necessary, and there is a problem that reliability is lacking. In particular, in an ink jet recording apparatus used for a device such as a facsimile which may cause a time during which its operation is not monitored by an operator or the like, there is a possibility that a recovery process is not performed when necessary and good recording cannot be performed. It will be great.

The present invention has been made in view of the above-mentioned problems of the conventional technology, and detects a change in the temperature of the print head due to the above-mentioned idle discharge operation, and based on the detected change in the temperature of the print head, determines whether or not the print head is defective. An object of the present invention is to provide an ink jet recording apparatus and a non-ejection detection method capable of performing a recovery operation in accordance with a use condition of the apparatus by determining ejection and performing a recovery operation.

[0009]

A non-discharge detection method according to the present invention is a non-discharge detection method performed by an ink jet recording apparatus that performs recording by discharging ink. Causing the head to perform idle discharge not used for recording; a first temperature before the recording head performs the idle discharge; a second temperature at the end of the idle discharge; Detecting a third third temperature,
The printhead is calculated based on the temperature rise value of the printhead due to the idle discharge indicated by the second temperature and the second temperature, and the temperature decrease value of the printhead after the idle discharge indicated by the second temperature and the third temperature. Is determined to be non-discharge.

Further, according to the present invention, there is provided an ink jet recording apparatus for performing recording by discharging ink, wherein a temperature detecting means for detecting a temperature of a recording head for discharging the ink; An idle ejection drive control unit that causes the head to perform idle ejection that is not used for recording; and an idle ejection operation performed by the idle ejection drive control unit, and a temperature change that occurs in the print head due to the idle ejection operation is detected from the temperature detection unit. A control device is provided for determining whether or not the recording head is in non-discharge according to a value of a temperature rise of the recording head due to idle discharge and a temperature decrease of the print head after completion of idle discharge.

In this case, the apparatus may include recovery means for performing a print head discharge recovery process, and the control device may operate the recovery means when it is determined that the print head is not discharging.

In the idle discharge operation for detecting non-discharge, the recording head is accommodated in a cap that communicates with the pump so that the ink discharge surface of the recording head does not contact the cap, and the idle discharge of ink by the recording head is performed. And the suction operation by the pump may be performed almost simultaneously.

Further, a blade for wiping the discharge port surface of the recording head may be provided, and the wiping operation by the blade may be performed after the idle discharge operation at the time of non-discharge detection.

[0014]

According to the above arrangement, it is determined whether or not this recording head is non-discharged in accordance with the temperature rise which occurs in the recording head due to the idle discharge performed in advance and the temperature decrease which occurs in the print head after the idle discharge. You.

That is, when there is a non-ejection in the recording head, the value of the temperature rise and the value of the temperature decrease greatly increase as compared with the case where the ejection is performed well. Therefore, for example, when the temperature change exceeds a predetermined value (for example, the sum thereof), it can be determined that a non-ejection state has occurred in the print head.

By using both the temperature rise and the temperature decrease, it is possible to judge the non-ejection state even if the temperature of the recording head has changed, and to print immediately before performing the non-ejection detection. Even if the temperature of the recording head rises and the temperature of the recording head subsequently decreases, it is possible to make an accurate determination.

[0017]

Next, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a diagram showing a configuration example of an embodiment of an ink jet recording apparatus according to the present invention.

In the drawing, reference numeral 9 denotes a head cartridge having an ink jet recording head, which will be described in detail with reference to FIGS. 2 and 3, and reference numeral 11 denotes a carriage for mounting the same and scanning in the S direction in the drawing. 13 is a hook for attaching the head cartridge 9 to the carriage 11, and 15 is a hook 13
It is an operation lever for operating. This operation lever 1
5 is provided with a marker 17 for indicating a scale provided on a device cover (not shown) so that the print position and set position of the head cartridge 9 by the recording head can be read. Reference numeral 19 denotes a support plate that supports an electrical connection to the head cartridge 9. Reference numeral 21 denotes a flexible cable for connecting the electric connection unit and the main body control unit.

Reference numeral 23 denotes a guide shaft for guiding the carriage 11 in the S direction, and is inserted through a bearing 25 of the carriage 11. Reference numeral 27 denotes a timing belt to which the carriage 11 is fixed and which transmits power for moving the carriage 11 in the S direction, and pulleys 29 arranged on both sides of the apparatus.
A, 29B. A driving force is transmitted to one pulley 29B from a carriage motor 31 via a transmission mechanism such as a gear.

Reference numeral 33 denotes a conveying roller for regulating the recording surface of a recording medium such as paper (hereinafter also referred to as recording paper) and conveying the recording medium during recording or the like. 37 is a paper pan for guiding the recording medium to the recording position from the paper feed tray side, and 39 is disposed in the middle of the recording medium feeding path to press the recording medium toward the conveying roller 33 and convey it. Feed roller. Reference numeral 34 denotes a platen that faces the ejection port forming surface of the head cartridge 9 and regulates the recording surface of the recording medium. Reference numeral 41 denotes a discharge roller that is disposed downstream of the recording position in the recording medium transport direction and discharges the recording medium toward a discharge port (not shown). Reference numeral 42 denotes a spur provided corresponding to the paper discharge roller 41.
1 is pressed to generate a conveyance force of the recording medium by the discharge roller 41. Reference numeral 43 denotes a release lever for releasing the urging of each of the feed roller 39, the holding plate 45, and the spur 42 when setting a recording medium or the like.

Reference numeral 45 denotes a pressing plate for suppressing the floating of the recording medium in the vicinity of the recording position and ensuring the state of close contact with the transport roller 33. In the present embodiment, an ink jet recording head that performs recording by discharging ink is employed as a recording head. Therefore, the distance between the ink discharge port forming surface of the recording head and the recording surface of the recording medium is relatively small, and the distance must be strictly controlled to avoid contact between the recording medium and the discharge port forming surface. The arrangement of the holding plate 45 is effective. Reference numeral 47 denotes a scale provided on the presser plate 45, and reference numeral 49 denotes a marker provided on the carriage 11 corresponding to the scale, and the print position and the set position of the recording head can also be read by these.

Reference numeral 51 denotes a cap formed of an elastic material such as rubber which faces the ink discharge port forming surface of the recording head at the home position, and is supported so as to be capable of coming into contact with and detaching from the recording head. The cap 51 is used for protection of the recording head during non-recording or the like, prevention of ink drying, and the above-described ejection recovery processing of the recording head. The ejection recovery process is a process in which ink is ejected from all ejection ports by driving an energy generating element provided inside the ink ejection ports and used for ink ejection, thereby recording air bubbles, dust, and thickening. A process for removing the cause of ejection failure such as ink that is no longer suitable for printing (the above-described idle ejection), and a process for removing the cause of the ejection failure by forcibly discharging the ink from the ejection port by suction separately from the process (as described above) Ink suction).

Reference numeral 53 denotes a pump used to apply a suction force for forcibly discharging the ink and to suck the ink received by the cap 51 during the discharge recovery process by the forced discharge and the discharge recovery process by the idle discharge. . Reference numeral 55 denotes a waste ink tank for storing the waste ink sucked by the pump 53, and reference numeral 57 denotes a tube that connects the pump 53 and the waste ink tank 55.

Reference numeral 59 denotes a blade for wiping the ejection port forming surface of the recording head, which protrudes toward the recording head to perform wiping in the process of moving the head, and a retreating blade that does not engage with the ejection port forming surface. It is movably supported in the position. 61 is a motor, 63 is a drive of the pump 53 and a cap 5
1 and a cam device for moving the blade 59, respectively.

Next, the details of the head cartridge 9 will be described.

FIG. 2 is a perspective view showing the appearance of a head cartridge 9 in which an ejection unit 9a and an ink tank 9b forming an ink jet recording head main body are integrated. In FIG. 2, reference numeral 906e denotes a carriage 11 when the head cartridge 9 is mounted. The hook is hooked by a hook 13 provided on the hook. As is clear from the figure, the pawl 906e is disposed inside the full extension of the recording head. In addition, a positioning abutting portion (not shown) is provided near the front ejection unit 9a of the head cartridge 9. Reference numeral 906f denotes a head opening in which a support plate for supporting a flexible substrate (electric connection portion) and a rubber pad is inserted upright on the carriage 11.

FIG. 3A is a sectional view of the head cartridge 9 as viewed from above, FIG. 3B is a front view of the head cartridge 9 as viewed from the front of the discharge port, and FIG. FIG.

The recording head used in this embodiment is a substrate made of silicon or the like on which an electrothermal transducer (discharge heater) for generating the above-mentioned thermal energy, electrode wiring for applying an electric pulse thereto, and a drive element are formed. [Hereinafter referred to as HB (heater board)], an Al substrate formed of, for example, Al and an HB which supports the HB and serves as a radiator plate.
And a top plate for forming an ink liquid passage and the like which communicates with each of the discharge ports and forms an action portion of the thermal energy.

The head cartridge 9 includes the ejection unit 9a and the ink tank 9b as described above. The ink in the ink tank 9b is
The liquid is guided to the common liquid chamber 902 of the discharge unit 9a via the liquid crystal unit 04. On the Al substrate 906 and the HB substrate 907 constituting the discharge unit 9a, a common liquid chamber 902 and, for example, 64 liquid paths communicating with the common liquid chamber 902 and partition walls for discharge ports provided in the respective liquid paths are provided. Thus, a discharge port array 901 is formed. Further, a discharge heater 908 is formed on the HB substrate 907 corresponding to each of the liquid paths, and a head temperature sensor 903 is formed on the same HB substrate 907. When viewed from the discharge port side, an HB substrate 907 on which a discharge heater 908, a head temperature sensor 903, wiring, etc. are formed is adhered on an Al substrate 906, and a top plate 909 is further stacked thereon. An ejection port is formed.

FIG. 4 shows a configuration example of a control system of the ink jet recording apparatus according to this embodiment.

In FIG. 1, reference numeral 100 denotes a microprocessor-type CPU which forms a main control unit of the apparatus, and executes necessary processing based on data and control signals input from the keyboard 1. Reference numeral 102 denotes a crystal oscillator that generates a basic clock for defining the operation timing and the like of each unit. 104 corresponds to a recording control procedure or the like executed by the CPU 100, and a ROM for storing the above-mentioned programs and other fixed data; 106, a storage area for work (work) data used as a register or the like, a document (text), etc. And a ROM 108 used as a character generator. Reference numeral 110 denotes a display controller for displaying data on, for example, a liquid crystal display (LCD).

Reference numeral 114 denotes a head controller, which is a head driver 1 for driving an ejection energy generating element group (ejection heater group) of the ejection unit (recording head) 9a.
16 control signals (COM1-8, SEG1-8) are generated. Reference numeral 118 denotes a motor driver for driving the carriage motor 31 and the transport motor 35. The drive control signals CM1 to CM4 for the carriage motor 31 are supplied from the head controller 114, and the drive control signals PM1 to PM4 for the transport motor 35 are supplied from the CPU 100.

Reference numeral 120 denotes an RA used as a buffer for storing, for example, one line of data received for recording and data used for recording obtained by processing the data.
M. 122 is the ROM 104 and RAM 10 described above.
6, an address / data bus for connecting the ROM 108, the display controller 110, and the head controller 114, and R / W is a control signal for switching the read / write state of each section 104 to 108 and 114. CP
U100 is connected to the head temperature sensor 9 shown in FIG.
03, the detected temperature is confirmed, and the control based on the detected temperature is performed.

FIG. 5 is a diagram for explaining a non-discharge detection method performed in the present embodiment configured as described above.

The non-discharge detection method performed in this embodiment is as follows.
The predetermined time (t ₁ -t ₀₎ idle discharge temperature rise of the recording head after the (T ₁ -T _0), then the predetermined time (t ₂ -
t ₁ ), the temperature of the print head during non-ejection (T ₁ −
T ₂ ) and the sum of these temperatures (T ₁ −T ₀ ) + (T ₁ )
If (−T ₂ ) = (2T ₁ −T ₀ −T ₂ ) is equal to or greater than the predetermined value T _Th , it is determined that there is a discharge port in a non-discharge state.

As described above, according to the sum of the temperature rise of the head temperature during the idle discharge and the temperature decrease after the idle discharge, the non-discharge state is determined.
The grounds on which the determination can be made can be explained as follows.

That is, recording using a method in which a film boiling is generated in the ink using thermal energy as used in the present embodiment, and the ink is discharged along with the growth of bubbles due to the film boiling. Taking the case of a head as an example, this recording head is formed by bonding the above-described HB substrate, and an Al substrate and an HB substrate formed of, for example, Al, which support the HB substrate and serve as a heat sink. It comprises a discharge port and a top plate which communicates with each of the discharge ports to form an ink liquid path or the like which functions as the action section of the thermal energy.

When discharging is performed in the recording head having this structure, the discharge heater generates heat by applying an electric pulse. As described above, this thermal energy is transmitted to the ink and used for ink ejection by the growth of bubbles, and a part of the thermal energy is transmitted to the HB substrate. However,
Most of the heat generated by the discharge heater is used for ink discharge, and this heat energy is stored in the discharged ink and converted into kinetic energy through the generation and growth of bubbles accompanying the ink discharge. Is discharged to the outside of the recording head.

However, in the case where ink does not discharge due to thickening and sticking of ink near the discharge port of the ink liquid path, or when normal discharge is not performed due to bubbles remaining in the ink liquid path, The heat generated by the discharge heater raises the temperature of the HB substrate without being discharged out of the print head. Therefore, the higher the non-ejection frequency, the higher the detected substrate temperature, or the higher the rate of change in temperature rise. Here, the above-described non-ejection frequency is defined for one ejection port and a plurality of ejection ports,
The non-ejection frequency is defined to be higher as the amount of ejected ink is smaller when the number of ejection ports is defined by one ejection port, and as the number of ejection ports with ejection failures is larger when the number of ejection ports is defined by a plurality of ejection ports.

FIG. 6 is a diagram showing the relationship between the number of non-ejection ejection ports, ie, the frequency of non-ejections, and the head temperature when idle ejection is performed by a recording head having 64 ejection ports arranged therein. Three print duties are shown for each. Here, the same number of ejections were performed for each ejection port in the idle ejection. As can be seen from the figure, the higher the frequency of non-discharge, the higher the temperature of the print head tends to be. In addition, the higher the print duty, the higher the rate of change in temperature. Therefore, it can be seen that the accuracy of temperature detection can be increased by increasing the print duty of idle discharge.

Next, the heat transmitted to the HB substrate during the idle discharge is radiated to the outside air from the HB substrate through the Al substrate functioning as a heat radiating plate at the same time as the completion of the idle discharge. Is rapidly cooled.

Since the temperature of the HB substrate is higher in a head in a non-discharge state, the temperature drop rate is higher than in a normal head in which no discharge is performed.

As described above, the idle discharge operation is performed before printing, and the non-discharge state of the print head is determined by detecting the temperature or temperature change at that time and the temperature or temperature change of the print head thereafter. Becomes possible.

FIG. 7 shows the CP in this embodiment shown in FIG.
9 is a flowchart illustrating a procedure of a non-discharge detection process performed by U100.

Although the non-discharge detection process in this embodiment can be performed irrespective of the printing type such as monochrome or color, a case where full-color printing is performed using a plurality of recording heads will be described.

When this processing procedure is started, first, in step S701, the temperature T _{0 of the} recording head detected by the head temperature sensor 903 is detected, and this is indicated by R in FIG.
The print head temperature before idle discharge is stored in a predetermined area of the AM 106. Instead of this processing, the recording head may be controlled to a predetermined temperature of, for example, about 25 ° C. by a sub-heater or the like provided in the recording head. When such control is performed, the head temperature before idle discharge is always constant, and it is possible to prevent the viscosity of the ink from increasing in a low-temperature environment and to prevent unstable discharge during idle discharge. it can. Here, when a cap member that is also used for suction or the like is used as a member for receiving ink at the time of idle discharge, the idle suction of the pump may be performed almost simultaneously with the start of idle discharge at step S702. Performing such idle suction of the pump does not cause ink to overflow from the cap.
This is effective when the amount of idle discharge is larger than the amount of ink that can be held in the cap.

Next, in step S703, idle discharge is performed from all the discharge ports in a predetermined discharge pattern such that each discharge port has a uniform discharge number. The driving conditions at this time are preferably set to a maximum driving frequency and a driving voltage and a pulse width larger than usual, in order to improve detection accuracy.
In this process, it goes without saying that an operation of making an ink receiving member such as a cap member face the ejection opening surface of the recording head is included.

This idle discharge takes a predetermined time (t _1-
t ₀ ) is performed. Next step S704
Detects the print head temperature T ₁ immediately before the end of the idle discharge, and calculates the temperature rise T ₁ -T ₀ from this temperature and the print head temperature detected before the idle discharge. Next, after the idle ejection, a standby state is set until a predetermined time (t ₂ −t ₁ ) elapses (step S705), and the temperature (T ₂ ) of the print head when the above time elapses is detected (step S705). Step S
706), and calculates the temperature lowering from the spit immediately after the temperature (T ₁₎ to (T ₂ -T _1).

Next, the sum of the two calculated temperature differences (T
₁₋ T ₀ ) + (T ₂ −T ₁ ) = (2T ₁ −T ₀ −T ₂ ) is calculated (step S707). At this time, step S70
If the pump has been idled in step 2, step S708
To terminate the idle suction of the pump.

In the following step S709, the temperature calculated in step S707 is set to a predetermined value T.
_It is determined whether it is smaller than _Th . Here, as shown in FIG. 5, when the calculated temperature of the recording head is higher than T _Th, it is determined that there is an ejection port in a non-ejection or ejection failure state, and in the subsequent step S710, an ejection recovery process by ink suction is performed. Is performed, and a wiping process is performed in step S711,
After performing idle discharge for preventing color mixing in step S712, the non-discharge detection processing is terminated and recording processing is performed. In step S709, when the value of the temperature rise is equal to or less than T _Th , it is determined that there is no non-discharge or the like, and the process immediately proceeds to step S711.
After performing the idle discharge for preventing color mixing, the non-discharge detection processing is terminated and the recording processing is performed.

The wiping process after the end of the idle discharge performed in step S711 may be omitted. However, since the ejection opening surface of the head after the end of the idle discharge is often wet with ink, it is not used. Thereafter, it is preferable to perform wiping because the printing surface may be stained or the ejection may be hindered by the wet ink. In the case where full-color printing is performed using a plurality of heads as in the present embodiment, and when one wiper blade is used, color mixing can be prevented by performing idle discharge performed in step S712.

According to the above arrangement, it is possible to perform the ejection recovery process by suctioning ink only when the recording head is not discharging, thereby preventing the ink from being consumed by the suctioning. Can be.

The above-described non-discharge detection and recovery processing is particularly effective in detecting non-discharge due to air bubbles entering the discharge port after being left for a long time, and is effective when the power is turned on.

In each of the above embodiments, the idle discharge operation is driven by a single pulse with a predetermined drive voltage and a predetermined pulse width. However, it may be driven by a plurality of divided pulses, and in the case where non-ejection occurs due to high efficiency of heat acting on ink by performing idle ejection by using divided pulses in this way, Recovery can be performed effectively.

Further, when ordinary recording is performed by the divided pulse driving, a pulse that does not cause ejection may be performed by a pre-pulse of the divided pulse.

In addition, in each of the above embodiments, idle discharge is performed for a predetermined time, and non-discharge is determined accordingly.
Non-discharge may be determined based on a predetermined number of idle discharges instead of time.

FIG. 8 is a diagram showing a non-discharge detection method performed in the second embodiment of the present invention. In this embodiment, the (head) temperature detection before performing the idle discharge is performed a predetermined number of times (here, four times) at a relatively short predetermined time interval, and the total is defined as the temperature T ₀ before the idle discharge. Similarly, the head temperature T ₁ immediately before the end of the idle discharge and the head temperature T ₂ after a predetermined time after the end of the idle discharge are measured, and (T ₁ −T ₀ ) + (T ₁ −T ₂ ) = 2T ₁
When the value of -T ₀ -T ₂ is larger than a predetermined T _Th , the ejection state is set.

By doing so, it is possible to detect the head temperature accurately by increasing the S / N ratio of the signal at the time of measuring the head temperature.

The present invention brings about an excellent effect particularly in a recording head and a recording apparatus of a bubble jet type proposed by Canon Inc. among ink jet recording types. This is because according to such a method, it is possible to achieve higher density and higher definition of recording.

The typical configuration and principle are described in, for example, 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 is a so-called on-demand type,
Although it can be applied to any type of continuous type, in particular, in the case of the on-demand type, it can be applied to a sheet holding liquid (ink) or an electrothermal converter arranged corresponding to the liquid path. By applying at least one drive signal corresponding to the recording information and providing a rapid temperature rise exceeding the nucleate boiling, heat energy is generated in the electrothermal transducer, and film boiling occurs on the heat-acting surface of the recording head. Cause
As a result, bubbles in the liquid (ink) corresponding to this drive signal one-to-one can be formed, which is effective. The liquid (ink) is ejected through the ejection opening by the growth and contraction of the bubble to form at least one droplet. 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 a liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. As the pulse-shaped drive 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 configuration (a linear liquid flow path or a right-angled liquid flow path) of a discharge port, a liquid path, and an electrothermal converter as disclosed in the above-mentioned respective specifications. U.S. Pat. No. 4,558,333 and U.S. Pat. No. 44,558 which disclose a configuration in which a heat acting portion is arranged in a bending region.
A configuration using the specification of Japanese Patent No. 59600 is also included in the present invention. In addition, Japanese Unexamined Patent Publication No. Sho 59-123670 discloses a configuration in which a common slit is used as a discharge portion of an electrothermal converter for a plurality of electrothermal converters, and an opening for absorbing a pressure wave of thermal energy is provided. The effect of the present invention is effective even if the configuration is based on JP-A-59-138461, which discloses a configuration corresponding to a discharge unit. That is, according to the present invention, recording can be reliably and efficiently performed regardless of the form of the recording head.

Further, the present invention can be effectively applied to a full-line type recording head having a length corresponding to the maximum width of a recording medium on which a recording apparatus can record. Such a recording head may have a configuration that satisfies the length by a combination of a plurality of recording heads, or a configuration as one integrally formed recording head.

In addition, even in the case of the serial type as described above, a recording head fixed to the apparatus main body, or an electric connection with the apparatus main body or ink from the apparatus main body by being attached to the apparatus main body. The present invention is also effective when a replaceable chip-type recording head that can be supplied or a cartridge-type recording head in which an ink tank is provided integrally with the recording head itself is used.

It is preferable to add recovery means for the printhead, preliminary auxiliary means, and the like provided as a configuration of the printing apparatus in the present invention, since the effects of the present invention can be further stabilized. . Specific examples include capping means for the recording head, cleaning means, pressurizing or suction means described above, preheating by means of an electrothermal transducer or another heating element or a combination thereof. It is also effective to perform a preliminary ejection mode in which ejection is performed separately from the means and printing in order to perform stable printing.

The type and number of recording heads to be mounted are not limited to those provided only for one color ink, for example, and for a plurality of inks having different recording colors and densities. A plurality may be provided. That is, for example, the printing mode of the printing apparatus is not limited to a printing mode of only a mainstream color such as black, but may be any of integrally forming a printing head or a combination of a plurality of printing heads. The present invention is also extremely effective for an apparatus provided with at least one of full colors by color mixture.

In addition, in the embodiments of the present invention described above, the ink is described as a liquid. However, an ink which solidifies at room temperature or lower and which softens or liquefies at room temperature, or an ink jet system In general, 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. Anything can be used. In addition, positively prevent the temperature rise due to thermal energy by using it as energy for changing the state of the ink from a solid state to a liquid state, or use an ink that solidifies in a standing state to prevent evaporation of the ink. In any case, in any case, the ink is liquefied by the application according to the recording signal of the thermal energy, and the liquid ink is ejected, such as the one that already starts to solidify when it reaches the recording medium,
The present invention is also applicable to a case where ink having a property of being liquefied for the first time by thermal energy is used. In such a case, the ink is held in a state in which the ink is held as a liquid or a solid in the concave portion or through hole of the porous sheet as described in JP-A-54-56847 or JP-A-60-71260. Alternatively, it may be configured to face the electrothermal converter. In the present invention, the most effective one for each of the above-mentioned inks is to execute the above-mentioned film boiling method.

Further, the form of the ink jet recording apparatus of the present invention is not only used as an image output terminal of an information processing apparatus such as a computer, but also a copying apparatus combined with a reader or the like, and further, a facsimile apparatus having a transmission / reception function. And the like.

[0069]

As is apparent from the above description, in the non-discharge detection method for determining whether or not the recording head is non-discharge in accordance with the temperature change due to the idle discharge operation not used for printing, the recording during discharge is performed. It is possible to detect the temperature change of both the temperature rise of the head and the temperature decrease of the print head after ejection, and to accurately judge the non-ejection state of the print head from these values. Immediately before performing this detection method, printing can be performed and the recording head temperature can be increased, and thereafter, even in the process of decreasing the temperature of the recording head, accurate determination can be made.

As a result, by performing the recovery operation in accordance with the determination of non-ejection, it is possible to reliably perform printing without non-ejection without performing unnecessary recovery processing such as suction when the power is turned on. . In particular, since the ink is not unnecessarily consumed by the recovery processing, the running cost of the apparatus can be reduced. Therefore, if the present invention is applied to a detachable and replaceable ink tank integrated type ink jet head cartridge, it is extremely effective.

Further, the amount of waste ink accompanying the recovery can be reduced, and the waste ink container can be kept mounted on the apparatus.

[Brief description of the drawings]

FIG. 1 is a perspective view of an ink jet recording apparatus according to a first embodiment of the present invention.

FIG. 2 is a perspective view of the head cartridge shown in FIG.

FIGS. 3A, 3B, and 3C are a top view of the head cartridge, a front view of a recording head, and a partially enlarged view of the recording head shown in FIG.

FIG. 4 is a block diagram showing a control configuration of the inkjet recording apparatus shown in FIG.

FIG. 5 is a diagram for explaining a non-discharge detection method according to the first example of the present invention.

FIG. 6 is a diagram illustrating a relationship between a non-ejection frequency and a temperature rise of a print head.

FIG. 7 is a flowchart illustrating a non-ejection detection process according to the first embodiment of the present invention.

FIG. 8 is a diagram for explaining a non-discharge detection method according to a second embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Keyboard 6 Display 9 Head cartridge 9a Discharge unit 9b Ink tank 11 Carriage 13 Hook 15 Operation lever 17, 49 Marker 19 Support plate 23 Guide shaft 25 Bearing 27 Timing belt 29A, 29B Pulley 31 Carriage motor 33 Transport roller 34 Platen 35 Transport Motor 37 Paper pan 39 Feed roller 41 Discharge roller 42 Spur 43 Release lever 45 Press plate 47 Scale 51 Cap 53 Pump 55 Waste ink tank 57 Tube 59 Blade 100 CPU 102 Crystal oscillator 104, 108 ROM 106, 122 RAM 110 Display controller 114 Head controller 116 Head driver 118 Motor driver 122 Address / data bus 131 Interface 90 Outlet row 902 common liquid chamber 903 head temperature sensor 904 ink passage 905 filter 906 Al substrate 907 HB substrate 908 ejection heaters 909 top plate 906e claw 906f head opening S701~S712 step

──────────────────────────────────────────────────続 き Continuation of the front page (72) Inventor Hitoshi Nishikori 3-30-2 Shimomaruko, Ota-ku, Tokyo Inside Canon Inc. (56) References JP-A-61-98542 (JP, A) JP-A-3 -240553 (JP, A) JP-A-3-234657 (JP, A) (58) Fields investigated (Int. Cl. ⁶ , DB name) B41J 2/175 B41J 2/05

Claims (5)

(57) [Claims] 1. A non-discharge detection method performed by an ink jet recording apparatus that performs recording by discharging ink, comprising: causing a recording head for discharging the ink to perform idle discharge not used for recording. Detecting a first temperature before the idle discharge of the recording head, a second temperature at the end of the idle discharge, and a third temperature after a predetermined time after the idle discharge is completed; The printhead is calculated based on the temperature rise value of the printhead due to the idle discharge indicated by the second temperature and the second temperature, and the temperature decrease value of the printhead after the idle discharge indicated by the second temperature and the third temperature. A non-discharge detection method for determining whether or not a non-discharge is detected. 2. An ink jet recording apparatus which performs recording by discharging ink, wherein: a temperature detecting means for detecting a temperature of a recording head for discharging the ink; Idle discharge drive control means for performing discharge; controlling idle discharge operation by the idle discharge drive control means; detecting a temperature change occurring in the print head by the idle discharge operation from the temperature detecting means; An ink jet recording apparatus, comprising: a control device that determines whether or not the recording head is in a non-discharge state in accordance with values of a temperature rise and a temperature decrease of the recording head after completion of idle discharge. 3. The ink jet recording apparatus according to claim 2, further comprising recovery means for performing a print head ejection recovery process, wherein the control device operates the recovery means when it is determined that the print head is not ejected. An ink jet recording apparatus characterized in that: 4. The ink jet recording apparatus according to claim 2, wherein the idle discharge operation at the time of non-discharge detection is performed by setting the ink discharge surface of the print head in a cap that connects the print head to a pump. An ink jet recording apparatus which is housed so as not to come into contact with a cap, performs idle discharge of ink by a recording head, and performs idle suction operation by the pump almost simultaneously. 5. The ink jet recording apparatus according to claim 2, further comprising a blade for wiping an ejection port surface of a recording head, and after a non-ejection operation when non-ejection detection is performed. An inkjet recording apparatus, wherein the blade performs a wiping operation.