JPH0994980A - Ink jet recorder and ink detecting method for the recorder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve the reliability of the decision result of the color of ink to be detected and to accurately detect the ink residues of ink jet heads by altering the moving speed of the jet in response to the color of the ink to be discharged, and checking the ink detection signal discharged in synchronization of the ink discharge. SOLUTION: A recording head is so moved at a predetermined speed that the discharged ink crosses the optical axis (slit) of a photointerrupter while discharging the ink from the recording head of the color corresponding to the head. At this time, the moving speed of the head is altered at each ink color to be detected for detecting the ink residue. When the ink is discharged between a light emitting element 101 and a light receiving element 102 and the light quantity arriving at the element 102 upon the emission of the light from the element 101 is reduced, the current flowing the element 102 is reduced. Thus, the level of a signal 103 is raised, the raised level is detected to detect the ink quantity discharged from the head.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus for performing recording by moving a carriage equipped with an ink jet head relative to a recording medium, and an ink detecting method in the apparatus.

[0002]

2. Description of the Related Art As a method for detecting the presence or absence of ink in an ink tank (ink cartridge) provided in an inkjet head in an inkjet printer,
Various methods have been proposed. For example, there is a method of ejecting an ink droplet between photo interrupters, amplifying the output of the photo interrupter, and detecting the presence or absence of ink based on the amplified signal level. In addition, in order to detect the presence or absence of ink, a mark for detecting the presence or absence of ink is printed on the recording medium, and the presence or absence of ink remaining is determined by whether or not the detection mark is properly printed by the reflective photosensor. There was also a way to judge.

[0003]

However, in the former method among the conventional methods, when the ink is ejected between the photosensors, the ink jet head is once moved between the photosensors and stopped there. When ink is ejected, as the resolution of the inkjet recording device improves,
Since the ejected ink droplets are small, it may not be possible to eject the ink droplets on the optical axis of the photo interrupter accurately. Therefore, the recording head is moved while ejecting ink near the optical axis of the photo interrupter,
At that time, it is considered that the ink is detected by the ink droplet crossing the optical axis.

However, in the case of color inks, the light-shielding characteristics for the photo interrupter are different for each color. Therefore, if ink detection is performed in the same sequence regardless of the difference in color, the reliability of the determination result will deteriorate. was there.

Further, in the latter mark method, although the detection accuracy is high, in order to detect the presence or absence of ink, it is necessary to record an unnecessary mark on the recording medium.
Therefore, the recording medium is wastefully used, and a sensor for reading the mark with high accuracy is required.

The present invention has been made in view of the above conventional example, and when ejecting ink to detect the ink amount, the determination result is obtained by changing the moving speed of the carriage in correspondence with the color of the ink to be detected. It is an object of the present invention to provide an ink jet recording apparatus with improved reliability and a method for detecting ink in the apparatus.

Another object of the present invention is to provide an ink jet recording apparatus which can detect the ink remaining amount of each head with high accuracy regardless of each ink color, and an ink detecting method in the apparatus.

[0008]

In order to achieve the above object, the ink jet recording apparatus of the present invention has the following constitution. That is, an inkjet recording apparatus that performs recording by moving a carriage equipped with an inkjet head relative to a recording medium, is provided at a predetermined position within a moving region of the inkjet head, and is ejected from the inkjet head. Detecting means for detecting the ink and outputting a detection signal, moving means for moving the inkjet head, and ejecting ink near the predetermined position including the predetermined position while moving the inkjet head by the moving means. Ink ejecting means, control means for changing the moving speed of the inkjet head by the moving means according to the ink color ejected by the ink ejecting means, and the detection signal in synchronization with the ink ejecting by the ink ejecting means. And a determination means for determining whether or not ink is ejected .

In order to achieve the above object, the ink detecting method in the ink jet recording apparatus of the present invention comprises the following steps. That is, a method of detecting ink in an inkjet recording apparatus that performs recording by moving a carriage equipped with an inkjet head relative to a recording medium, the method comprising: moving the inkjet head toward an ink ejection detection position; An ink ejection step of ejecting ink continuously in the vicinity of the ink ejection detection position including the ink ejection detection position while moving the ink jet head, and the movement of the ink jet head according to the ink color ejected in the ink ejection step The method includes a step of changing the speed and a step of determining the presence / absence of ink ejection of the corresponding color based on the detection signal detected at the ink ejection detection position.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to one embodiment of the present invention,
While moving, the inkjet head is driven at a predetermined cycle to eject ink.

Further, according to the present embodiment, the detecting means includes a light emitting element and a light receiving element, and the ink ejected from the ink jet head between the light emitting element and the light receiving element is used to detect the light reaching the light receiving element. A detection signal based on the amount of change is output.

Further, according to the present embodiment, the moving speed of the carriage (ink jet head) is reduced in the case of ink having a low light-shielding property or in the case of ink having a high viscosity. When the number of nozzles of the head that ejects that color is large, the moving speed of the carriage is increased.

Further, the detection position of ink ejection is determined based on the home position of the carriage.

Further, according to the present embodiment, the ink jet head is provided with the electrothermal converter, the heat applied to the ink by the electrothermal converter causes the ink to change the state, and the ink drop is caused by the state change. Discharge.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

First, the structure of the ink jet recording apparatus according to the embodiment of the present invention will be described in detail with reference to FIGS.

FIG. 2 is a side sectional view showing the construction of an ink jet recording apparatus for recording with a recording head (ink jet head) according to the ink jet system which is an embodiment of the present invention.

In FIG. 2, A is a recording unit for performing recording according to the ink jet system, and B is a paper feeding unit that separates recording media such as recording paper P stacked in a paper feeding cassette 1 sheet by sheet and supplies them to the recording unit A. It is a department.

First, the flow of the recording paper P will be described.
The recording paper P stacked in the paper feed cassette 1 of the paper feed unit B is picked up by the paper feed roller 2 and the retard roller 3, and fed to the recording unit A by the rotation of the paper feed roller 2. In the recording unit A, the recording head 5 ejects ink onto the recording paper P to perform recording, and the recording paper P is conveyed in accordance with the recording. When the recording for one page is completed, the recording paper P is discharged by the rotation of the paper discharge roller 6 and is stacked on the paper discharge stacker 7.

Next, the specific construction of the paper feed section B will be described.

In FIG. 2, a paper feed cassette 1 for accommodating and accommodating a plurality of recording papers P is an intermediate plate 4 for accommodating the recording papers P.
It has. The middle plate 4 is urged upward from the back surface by a middle plate spring 10 arranged to face the feeding roller 2. Further, the middle plate 4 is pressed downward by a cam or the like in the standby state for feeding, so that the recording paper P can be easily replenished when the recording paper P becomes small or runs out.

On the other hand, when the recording signal is detected and the paper feeding operation is started, the downward pressing of the intermediate plate 4 by the cam or the like is released,
The recording paper P is picked up by the paper feed roller 2.
The retard roller 3 is at a position facing the paper feed roller 2 and changes the position of the recording paper P in conjunction with the intermediate plate 4. When the paper feeding operation is performed, the uppermost one sheet of the recording paper P, which is urged upward by the middle plate 4 and picked up by the paper feeding roller 2, serves as the paper feeding roller 2 and the retard roller 3 in the J section. They are separated and fed by cooperating action. The recording paper P separated and fed in this manner is nipped so as to be sufficiently wrapped around the feeding roller 2 and conveyed to the recording unit A.

Next, the discharge mechanism of the recording paper P recorded in the recording section A will be described.

The recording paper P ejected by the paper ejection roller 6 is ejected and stacked on the paper ejection stacker 7. The paper discharge stacker 7 is provided with a paper discharge auxiliary tray 9 whose center of rotation is the hinge K, and when the recording paper P to be used is long, the paper discharge auxiliary tray 9 is rotated and discharged. The total length of the paper stacker 7 can be increased in the paper discharge direction of the recording paper P. Further, the paper discharge stacker 7 has a structure that also serves as a cover of the paper feed cassette 1. The paper discharge stacker 7 and the paper discharge auxiliary tray 9 are provided with a plurality of ribs (not shown), and the recording paper P on which recording is performed slides on the plurality of ribs and is sequentially stacked. .

Next, the structure of the recording section A will be described in detail with reference to FIG.

FIG. 3 is a three-dimensional perspective view showing the detailed structure of the recording section A. As shown in FIG. 3, the recording head 5 is capable of printing in a plurality of colors, for example, an ink tank containing Y (yellow) M (magenta) C (cyan) and black ink, and each ink tank. Built-in multiple inkjet heads that print based on more ink,
It is a cartridge type recording head that can be replaced with a new recording head when the ink is used up.

Here, the principle of ink ejection from the recording head 5 will be described. The recording head 5 generally has a fine liquid discharge port (orifice), a liquid passage and an energy acting portion provided in a part of this liquid passage, and energy for generating droplet forming energy for acting on the liquid in the acting portion. And a generator.

The energy generating section uses an electromechanical converter such as a piezo element, irradiates an electromagnetic wave such as a laser, absorbs it in a liquid there, and generates heat. There are those that are made to eject and fly, or those that are made to heat the liquid by an electrothermal converter and eject the liquid. Among them, in a recording head using a method of ejecting a liquid by thermal energy, liquid ejection ports (orifices) for ejecting recording liquid droplets to form flying liquid droplets can be arranged at high density. Therefore, it is possible to record at high resolution.

Further, the recording head using the electrothermal converter as the energy generating portion can be easily miniaturized as a whole, and IC technology and micro-technology, in which the technological progress and the reliability are remarkably improved in the recent semiconductor field. Since the advantages of processing technology can be fully utilized and it is easy to make it long and flat (two-dimensional), it is easy to make multiple nozzles and high-density mounting, and mass production is possible. It is also possible to reduce the manufacturing cost.

A recording head manufactured through a semiconductor manufacturing process using an electrothermal converter in the energy generating portion as described above generally has a liquid passage corresponding to each ink ejection port, and the liquid passage is provided for each liquid passage. An electrothermal converter is provided as a means for applying thermal energy to the liquid that fills the liquid and ejecting the liquid from the corresponding ink ejection port to form droplets for flight. The liquid is supplied from a common liquid chamber that is in communication with each other.

The configuration of the recording unit A will be described with reference to FIG.

In FIG. 3, the carriage 15 holds the recording head 5 with high precision, and the direction (main scanning direction, main scanning direction) of the recording paper P is orthogonal to the conveying direction (sub scanning direction, arrow G direction).
It is reciprocated in the direction of arrow H). In addition, the carriage 15
Is slidably held by a guide rod 16, an abutting portion 15a for fixing the belt 18 and the carriage 15. The reciprocating movement of the carriage 15 is performed by a pulley 17 and a timing belt 18 driven by a carriage motor 30 (FIG. 4). Supplied from the circuit. The recording head 5 and the flexible cable 19 are connected by press-contacting each other. A cap 20 is provided at the home position of the carriage 15 of the recording unit A and functions as an ink receiving unit. The cap 20 moves up and down as needed, and when it rises, it comes into close contact with the recording head 5 to cover its nozzle portion and prevent evaporation of ink and adhesion of dust.

In this apparatus, the recording head 5 and the cap 2 are
A carriage home sensor 21 provided on the apparatus main body and a light shielding plate 15b provided on the carriage 15 are used for positioning so that 0 and 0 are relatively opposed to each other. A transmission type photo interrupter is used for the carriage home sensor 21, and when the carriage 15 moves to the standby position, the light emitted from a part of the carriage home sensor 21 is blocked by the light shielding plate 15b. By utilizing this, it is detected that the recording head 5 and the cap 20 are relatively opposed to each other.

The recording paper P is fed upward from the lower side in the drawing,
The sheet is bent in the horizontal direction by the feeding roller 2 and the paper guide 22 and is conveyed in the arrow G direction (sub-scanning direction). The feeding roller 2 and the paper discharging roller 6 are respectively provided with a conveyance motor 31.
The recording paper P is driven by the rotation of (FIG. 5) and, if necessary, interlocks with the reciprocating movement of the carriage 15 to convey the recording paper P with high accuracy in the sub-scanning direction. Further, in the sub-scanning direction, there is provided a spur 23 which is made of a material having high water repellency and which comes into contact with the recording paper P only at its blade-shaped circumferential portion. The spur 23 is the discharge roller 6
The bearing member 23a is provided at a plurality of positions at predetermined positions in the main scanning direction at a position facing each other, and even if the unfixed image on the recording paper immediately after recording is contacted, the image is not affected and recording is performed. The paper P is guided and conveyed.

The ink detecting portion 8 has a light emitting element (LED) 101 and a light receiving element (phototransistor) 102, which will be described later with reference to FIG. 1, and as shown in FIG.
0 and the paper edge of the recording paper P are arranged at positions facing the nozzle row 5c of the recording head 5, and the ink droplet rows ejected from the plurality of nozzles of the recording head 5 are arranged in the longitudinal direction of the nozzles. The recording head 5 is provided with a transmissive phototransistor (102) that directly optically detects when viewed from the direction.
The ink-free state of can be determined from the output. The ink detection unit 8 used here uses an infrared LED for the light emitting element 101, and a lens is integrally formed on the light emitting surface of the infrared LED, so that light can be projected substantially parallel to the light receiving element 102. Further, on the light receiving surface of the light receiving element 102, a 0.7 mm × 0.7 mm hole is formed on the optical axis by a molding member, and the detection range is set in the height direction in the entire area between the light receiving element 101 and the light emitting element 102. Is 0.7 mm and the width direction is 0.7 mm.

The optical axis connecting the light emitting element 101 and the light receiving element 102 is arranged parallel to the nozzle row 5c of the recording head 5, and the distance between the light receiving element 101 and the light receiving element 102 is
When the length of the nozzle row 5c of the recording head 5 is longer and the optical axis thereof coincides with the position of the nozzle row 5c of the recording head 5, all ink droplets ejected from each nozzle of the recording head 5 are emitted from the light emitting element 101. It is configured such that it can pass through the detection range between the light receiving elements 102. Then, when the ink droplet passes through the detection range, the amount of light that the ink droplet blocks the light from the light emitting element 101 and reaches the light receiving element 102 is reduced, and thus the output of the phototransistor, which is the light receiving element 102, changes. Is obtained and the ink ejection amount is detected.

Incidentally, in order to position the nozzle row of the recording head 5 and the ink detecting portion 8 so as to be relatively opposed to each other, similarly to the positioning with the cap 20, a carriage home sensor provided in the main body of the apparatus. 21 is used.

In this embodiment, as shown in FIG. 4, the distance (L) from the position of the nozzle row 5c of the recording head 5 at the home position (HP) to the optical axis of the photo sensor 8 is set to the carriage 15. It is set as a constant in a control program for converting the number of steps of the driven carriage motor 30 and executing the recording operation in advance. In this way, when the carriage 15 is moved by a certain amount after the home position is detected, the position of the ink ejection row of the recording head 5 and the optical axes of the light emitting element 101 and the light receiving element 102 of the ink detection unit 8 are set. Is positioned. The ink ejection detection position may be the home position. However, as described above, in the present embodiment, since the diameter of the ink droplet ejected from the head is minute, the recording head 5 is moved at a predetermined speed (depending on the color) near the optical axis including this optical axis. By ejecting the ink droplets while moving with, the ink droplets are surely crossed on the optical axis.

FIG. 5 is a block diagram showing the control arrangement of the ink jet recording apparatus of this embodiment.

In FIG. 5, reference numeral 24 is a control unit for controlling the entire apparatus, and the control unit 24 is a CPU 25 and a CP.
A ROM 26 storing a control program (flowchart in FIG. 7) executed by U25 and various data, and a CPU
RAM used by 25 as a work area for executing various processes and temporarily storing various data
It has 27 etc.

As shown in FIG. 5, the recording head 5 is connected to the control unit 24 via a flexible cable 19, and the flexible cable 19 includes a control signal line from the control unit 24 to the recording head 5, an image signal line and the like. Has been.
The output of the ink detection unit 8 is input to the control unit 24 via the A / D conversion circuit 28, and the CPU 25 can analyze the ink ejection amount according to the A / D converted digital value. ing. The carriage motor 30 rotates according to the phase excitation signal output from the motor drive circuit 32 based on the signal from the control unit 24. Further, the control unit 24
Is a carriage motor 30 via a motor drive circuit 33.
The rotation of the carry motor 31 is controlled via the motor drive circuit 32.

Furthermore, the control unit 24 is a printer that receives a recording command and recording data from the external computer 56.
The interface 54 and the like are connected. Control unit 2
4 is connected to an operation panel 58 for the user of the apparatus to perform various operations and instructions. The operation panel 58 has a display unit (L) for displaying various messages to the operator.
CD) 59 is provided.

FIG. 1 is a diagram showing the positional relationship between the ink detection unit 8 and the recording head 5 of this embodiment.

As shown in FIG. 1, the recording head 5 of the present embodiment is a head 5 for ejecting inks of Y (yellow), M (magenta), C (cyan), and Bk (black).
Y, 5M, 5C and 5Bk are provided, and the number of nozzles of each head is 128 for each of the heads 5Y to 5C and 256 for the head 5Bk. The nozzles of these heads 5Y, 5M, 5C, 5Bk are arranged in one row in the direction orthogonal to the scanning direction H of the recording head 5.

When detecting the remaining ink amount (ejection amount) of the recording head 5, the control unit 24 moves the recording head 5 between the photo interrupters of the ink detection unit 8 to detect the corresponding color of the recording head 5. While ejecting ink from the head, the recording head 5 is moved at a predetermined speed so that the ejected ink crosses the optical axis (slit) of the photo interrupter. At this time, the moving speed of the recording head 5 is changed for each ink color for which the remaining ink amount is to be detected. This is, for example, speed A when inspecting the ink amount by ejecting yellow ink, speed B when inspecting magenta ink, speed C when cyan ink, and speed C when black ink. Like the speed D, the moving speed of the recording head 5 is changed according to the color of the ink to be inspected for ink ejection, and the ink is ejected. Then, the amount of change in output from the photo interrupter is input for each color, and if the amount of change is greater than a predetermined amount, it is determined that ink is present, and if it is less, it is determined that ink is absent.

Incidentally, here, for example, the higher the density of the color of the ink to be inspected, the higher the moving speed of the recording head 5, and conversely, the lower the density of the ink, the more the recording head 5 moves.
The moving speed may be decreased, or the moving speed may be determined according to the characteristics (viscosity, etc.) of the ink.

FIG. 6 is a block diagram showing the configuration of the ink detecting section 8 of this embodiment.

Reference numeral 101 is a light emitting element, for example, an infrared ray L
ED and 102 are phototransistors which are light receiving elements. In this example, the signal 103 is normally at a low level because the phototransistor 102 is turned on, and when ink is ejected between the light emitting element 101 and the light receiving element 102, the light emitting element 101 emits light to receive the light receiving element. When the amount of light reaching 102 decreases, the current flowing through the phototransistor 102 decreases. This gives signal 10
By increasing the signal level of No. 3 and detecting the increased level, the amount of ink ejected from the recording head 5 can be detected.

FIG. 7 is a flowchart showing the remaining ink amount detecting operation in the ink jet recording apparatus according to the embodiment of the present invention. The control program for executing this processing is R
It is stored in the OM 26.

In the figure, when the ink amount detection processing is instructed, it is determined in step S1 whether or not the printing operation is completed. If it is completed, the carriage 15 is moved toward the home position. At this time, the carriage 1
If 5 is at the home position, the processes of S1 and S2 are unnecessary. When the carriage 15 reaches the home position, the process proceeds from step S2 to step S3, the carriage 15 is moved at the speed A, and the yellow head 5Y is driven to eject ink in step S4. Then, in step S5, the digital value from the A / D conversion circuit 28 is input, and the remaining amount of yellow ink is detected based on the value. In step S5, if the amount of change in the output value (output value of the A / D conversion circuit 28) from the ink detector 8 is smaller than the predetermined amount, it is determined that there is no ink, and step S1 is performed.
In step 6, an alarm is generated and the fact that there is no ink is displayed on the display unit 59.

On the other hand, if it is determined that there is ink in step S5, the process proceeds to step S6, the carriage 15 is returned to the home position, and then the movement toward the ink detecting portion 8 is started at the speed B. Then, in step S7, the magenta head 5M is driven to eject ink, and in step S8, the digital value from the A / D conversion circuit 28 is input, and the remaining amount of magenta ink is detected based on the value. Also here, as in step S5, when the amount of change in the output value of the A / D conversion circuit 28 is smaller than the predetermined amount, it is determined that there is no ink, the process proceeds to step S16, an alarm is generated, and there is no ink. Is displayed on the display unit 59.

If it is determined in step S8 that ink is present, the flow advances to step S9 to return the carriage 15 to the home position in step S9, and then starts moving toward the ink detection portion 8 at speed C. Then, in step S10, the cyan head 5C is driven to eject ink, and in step S11, A
The digital value from the / D conversion circuit 28 is input, and the cyan ink remaining amount detection operation is performed based on the value. Also here, as in step S5 or S8, when the amount of change in the output value of the A / D conversion circuit 28 is smaller than a predetermined amount, it is determined that there is no ink, the process proceeds to step S16, an alarm is generated, and ink is exhausted. Is displayed on the display unit 59.

When cyan ink is detected, the process proceeds to step S12, the carriage 15 is returned to the home position, and then the movement toward the ink detecting portion 8 is started at the speed D. Then, in step S13, the black (Bk) head 5C is driven to eject ink, and in step S14, the digital value from the A / D conversion circuit 28 is input, and the black ink remaining amount detection operation is performed based on that value. To do. Again, step S
Similar to 5, S8 or S11, when the amount of change in the output value of the A / D conversion circuit 28 is smaller than the predetermined amount, it is determined that there is no ink, the process proceeds to step S16, an alarm is generated, and no ink is issued. It is displayed on the display unit 59.

When it is determined that the inks of all the colors are present, the process proceeds to step S15, the fact that the inks are present is displayed on the display unit 59, and the operation of detecting the remaining ink amount is completed.

In the ink ejection process in steps S4, S7, S10 and S13 of the above-mentioned process flow chart, the cycle of ejecting ink from each color head (the drive cycle of the recording head 5) depends on the moving speed of the carriage 15. However, even when the moving speed is the highest, for example, the speed D is equal to or lower than the moving speed at the time of normal recording, the light emitting element 101 is surely provided for any color ink. Ink is ejected onto the optical axis of the light receiving element 102.

As described above, according to the present embodiment, when detecting the remaining amount of ink in the recording head, the carriage 1 that conveys the recording head 5 according to the characteristics of the ink color to be ejected.
By changing the moving speed of 5, it is possible to more reliably determine the presence or absence of ink.

The carriage 15 corresponding to each color ink
The moving speed may be determined according to not only the light-shielding property of the ink but also the viscosity of the ink, the number of nozzles of the head that ejects the ink of that color, and the like.

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.

With regard to its typical structure and principle, for example, US Pat. Nos. 4,723,129 and 4740 are applicable.
What is done using the basic principles disclosed in 796 is preferred. This method can be applied to both the so-called on-demand type and continuous type, but especially 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 film boiling to an 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. The liquid (ink) is ejected through the ejection openings by the growth and contraction of the bubbles 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 the liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable.

As this pulse-shaped drive signal, those described in US Pat. Nos. 4,463,359 and 4,345,262 are suitable. If the conditions described in US Pat. No. 4,313,124 of the invention relating to the rate of temperature rise on 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 converters,
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 the 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.

Further, it is preferable to add recovery means for the recording head, preliminary means, etc. to the structure of the recording apparatus described above because the recording operation can be made more stable. If these are specifically mentioned, capping means for the recording head, cleaning means, pressure or suction means,
There is an electrothermal converter, a heating element other than this, or a preheating means by 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 plural 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 is made on the assumption that the ink is a liquid. However, even if the ink solidifies at room temperature or lower, it is possible to use an ink that softens or liquefies at room temperature. 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 the solid state to the 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, by applying thermal energy such as ink that is liquefied by applying thermal energy according to the recording signal and liquid ink is ejected, or that begins to solidify when it reaches the recording medium. The present invention can be applied to the case where an ink having a property of being liquefied 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.

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.

Further, the present invention may be applied to a system composed of a plurality of devices or an apparatus composed of one device. Further, it goes without saying that the present invention can be applied to the case where it is implemented by supplying a program to a system or an apparatus. In this case, the storage medium storing the program according to the present invention constitutes the present invention. Then, by reading the program from the storage medium to the system or device, the system or device operates in a predetermined manner.

[0070]

As described above, according to the present invention, when the ink is ejected to detect the amount of ink, the movement speed of the carriage is changed in accordance with the color of the ink to be inspected, so that the judgment result can be obtained. This has the effect of improving reliability.

Further, according to the present invention, there is an effect that the ink remaining amount of each color can be detected with high accuracy regardless of each ink color.

[0072]

[Brief description of drawings]

FIG. 1 is a diagram showing an ink detecting operation according to an embodiment of the present invention.

FIG. 2 is a side sectional view showing a configuration of an inkjet recording apparatus that performs recording by a recording head according to an inkjet system that is a typical embodiment of the present invention.

3 is a three-dimensional perspective view showing a detailed configuration of a recording unit A of the recording apparatus shown in FIG.

4 is a diagram showing a detailed configuration around an ink detection unit of a recording unit A. FIG.

FIG. 5 is a block diagram showing the configuration of the inkjet recording apparatus according to the present embodiment.

FIG. 6 is a circuit diagram of an ink detection unit according to an embodiment of the present invention.

FIG. 7 is a flowchart showing an ink detection operation of the inkjet recording apparatus according to the present embodiment.

[Explanation of symbols]

 5 recording head 8 ink detection unit 21 carriage home sensor 24 control unit 25 CPU 26 ROM 28 A / D conversion circuit 30 carriage motor 58 operation panel 101 light emitting element (LED) 102 light receiving element (phototransistor)

Front page continued (72) Inventor Atsushi Saito 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Shigeyuki Sugiyama 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc. (72) Inventor Ken Kono 3-30-2 Shimomaruko, Ota-ku, Tokyo Canon Inc.

Claims (11)

[Claims] 1. An inkjet recording apparatus for recording by moving a carriage carrying an inkjet head relative to a recording medium, the inkjet head being provided at a predetermined position within a moving region of the inkjet head. Detecting means for detecting the ejected ink and outputting a detection signal; moving means for moving the inkjet head; and ink near the predetermined position including the predetermined position while moving the inkjet head by the moving means. An ink ejecting means for ejecting the ink, a control means for changing a moving speed of the inkjet head by the moving means according to an ink color ejected by the ink ejecting means, and the ink ejecting means in synchronization with the ink ejecting means. Judgment hand that judges the presence or absence of ink ejection by checking the detection signal An ink jet recording apparatus characterized by having, when. 2. The ink jet recording apparatus according to claim 1, wherein the ink ejecting unit ejects ink by driving the ink jet head at a predetermined cycle while moving the ink jet head. 3. The detection means includes a light emitting element and a light receiving element, and a detection signal based on a change amount of light reaching the light receiving element by ink ejected from the ink jet head between the light emitting element and the light receiving element. The inkjet recording apparatus according to claim 1 or 2, wherein 4. The ink jet recording apparatus according to claim 1, wherein the control unit reduces the moving speed when the ink has a low light-shielding property. 5. The inkjet recording apparatus according to claim 1, wherein the predetermined position is determined based on a home position of the carriage. 6. The ink jet head includes an electrothermal converter, wherein heat applied to the ink by the electrothermal converter causes a state change in the ink, and the ink droplet is ejected by the state change. The inkjet recording device according to claim 1, wherein 7. A method of detecting ink in an inkjet recording apparatus for recording by moving a carriage carrying an inkjet head relative to a recording medium, the method comprising: moving the inkjet head in an ink discharge detection position direction. An ink ejection step of ejecting ink continuously in the vicinity of the ink ejection detection position including the ink ejection detection position while moving the ink jet head; and the inkjet according to an ink color ejected in the ink ejection step. An ink detection method comprising: a step of changing a moving speed of a head; and a step of determining whether or not ink of a corresponding color is ejected based on a detection signal detected at the ink ejection detection position. 8. The ink detection method according to claim 7, wherein in the ink ejection step, the ink jet head is driven at a predetermined cycle to eject ink while moving the ink jet head. 9. The ink ejection detection position includes a light emitting element and a light receiving element, and is based on a change amount of light reaching the light receiving element by ink ejected from the inkjet head between the light emitting element and the light receiving element. The ink detection method according to claim 7, wherein a detection signal is output. 10. The ink detection method according to claim 7, wherein the moving speed is lowered in the case of ink having a low light-shielding property. 11. The ink detection method according to claim 7, wherein the ink ejection detection position is determined based on a home position of the carriage.