JPH05338206A - Ink-jet recording device - Google Patents

Abstract

PURPOSE:To enable the discharge recovery operation of all discharge openings even in a recording region, obviate the need for the traveling time of a recording head up to the position of a recovery means and the time for discharge recovery operation and shorten a recording time. CONSTITUTION:A first electrode 17 for charging ink 14 in a discharge opening 52 and a second electrode 20 for attracting the discharged droplets 15 of ink 14 charged are mounted, a third electrode 23 for repulsing the satellites of the discharged droplets 15 is installed as required, and the timing of applied voltage to each electrode is controlled.

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 recording by ejecting ink from a recording means onto a recording material.

[0002]

2. Description of the Related Art A recording device having a function such as a printer, a copying machine, a facsimile, or a recording device used as an output device such as a composite electronic device including a computer, a word processor, etc., a workstation, etc. Image (including characters etc.) on the recording material (recording medium) such as paper or plastic thin plate based on
Is configured to record. The recording device can be classified into an ink jet type, a wire dot type, a thermal type, a laser beam type and the like depending on the recording type.

In a serial type recording apparatus which employs a serial scan system in which main scanning is performed in a direction intersecting a conveying direction (sub-scanning direction) of a recording material, the recording material is set at a predetermined recording position and then the recording material is recorded. An image is recorded (main scanning) by a recording unit (recording head) mounted on a carriage that moves along the material, and a predetermined amount of paper is fed (conveyed material to be recorded) after one row of recording is completed, After that, the operation of recording (main scanning) the image of the next row is repeated on the recording material that has stopped again, thereby recording the entire recording material. On the other hand, in a line type recording apparatus that records only by sub-scanning in the conveyance direction of the recording material,
The recording material is set at a predetermined recording position, and one sheet of recording is collectively performed, and the paper is continuously fed (pitch feeding) to record the entire recording material.

Of the above recording apparatuses, an inkjet recording apparatus (inkjet recording apparatus) is configured to eject ink from a recording unit (recording head) in accordance with an image signal and perform recording on a recording material. In addition, it is easy to make the recording means compact, it is possible to record high-definition images at high speed, it is possible to record on plain paper without requiring special processing, the running cost is low, and the non-impact method is used. Therefore, there is an advantage that there is little noise and that it is easy to record a color image using multicolor ink. Among them, the line type using a full multi type recording means in which a large number of ejection openings are arranged in the paper width direction can further speed up recording.

In particular, an ink jet type recording means (recording head) for ejecting ink by utilizing heat energy,
Through the semiconductor manufacturing process such as etching, vapor deposition, and sputtering, the electrothermal converter formed on the substrate, the electrode,
By forming a liquid path wall, a top plate, etc., it is possible to easily manufacture a product having a high-density liquid path arrangement (ejection opening arrangement), a simple and compact structure, and a high-resolution image at high speed. Can be recorded. On the other hand, there are various requirements for the material of the recording material. In recent years, in addition to plain paper and resin thin plate (OHP, etc.) which are ordinary recording materials, thin paper and processed paper (punch holes for filing). It has become necessary to use attached paper, perforated paper, paper of arbitrary shape, etc.

However, in the ink jet recording apparatus, since ink is ejected directly from the fine ejection openings provided on the ejection opening forming surface facing the recording material, special consideration is required for good recording. is there. For example, since a large number of ejection ports are formed in the recording head, ink is not necessarily ejected from all ejection ports, and there are ejection ports that are not used. If this unused state continues for a certain period of time, the amount of water evaporation of the ink near the ejection port increases and the ink viscosity increases, so reliable ink ejection and ink droplet flight cannot be obtained during recording, and eventually ejection It may be impossible. Therefore, an operation (recovery operation) that secures reliable ejection and flight is performed by ejecting a constant amount of ink from all the ejection ports at regular time intervals or at constant volume recording.

[0007]

However, in the conventional ink jet recording apparatus, the recording head has to be moved to the position of the recovering means for the recovery operation every recording for a fixed time or for a fixed amount of recording. There is a problem that the head moving time and the recovery operation time are required, and the recording time becomes long.

The present invention has been made in view of such technical problems, and an object of the present invention is to eliminate the time required for moving the recording means to the position of the recovery means and the time for the recovery operation. An object of the present invention is to provide an ink jet recording apparatus capable of performing recovery processing of the recording means and shortening recording time.

[0009]

According to the present invention, an electrode for adsorbing a charged ink droplet is provided in the vicinity of a discharge port of a recording head, and a voltage is applied to the electrode for charging the ink and the electrode for adsorbing the ink. By performing control, the recovery operation is performed at the timing when ink can be ejected from all ejection ports (for example, when the recording head is moving to the recording start position of the next shuttle after the recording of one shuttle is completed). By doing so, it is possible to shorten the recording time by eliminating the need for the moving time of the recording head to the position of the recovery means and the time for the recovery operation.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic perspective view showing a schematic configuration of an embodiment of an inkjet recording apparatus to which the present invention is applied. Figure 1
1a is a recording head (recording means) using yellow ink, 1b is a recording head using magenta ink, 1c is a recording head using cyan ink, and 1d.
Is a recording head using black ink. These recording heads 1a, 1b, 1c, 1d are composed of replaceable head cartridges (disposable heads) in which ink tanks of respective colors are integrated. In the following, when referring to all or any one of the recording heads 1a, 1b, 1c, 1d, the recording head 1 is simply referred to.
Alternatively, the recording means 1 will be used.

The recording head 1 is mounted on a carriage 2 which reciprocates along a guide rail 3 fixed to the main body of the apparatus. The carriage 2 is coupled to the timing belt 5, and reciprocates along the recording material 12 by converting forward / reverse rotation of the stepping motor (carriage motor) 4 into reciprocating linear movement of the timing belt 5. A predetermined tension is applied to the timing belt 5 by a pulley unit 6 arranged on the opposite side of the motor 4.

In each recording head 1, a large number of ejection openings are formed in an array in parallel to the conveying direction (sub-scanning direction) A of the recording material 12 such as paper or a thin plastic plate.
An electrothermal converter is built in each ejection port, and the electrothermal converter is selectively driven (energized) to eject and eject ink droplets from a predetermined ejection port. There is.

That is, the recording head (recording means) 1
Is an ink jet recording means for ejecting ink by utilizing heat energy, which is provided with an electrothermal converter for generating heat energy. Further, the recording head 1 performs recording by ejecting ink from an ejection port by utilizing a pressure change caused by growth and contraction of bubbles due to film boiling caused by thermal energy applied by the electrothermal converter. Is.

FIG. 2 is a partial perspective view schematically showing the structure of the ink ejection portion of the recording head 1. In FIG. 2, a plurality of ejection openings 52 are formed at a predetermined pitch on the ejection opening formation surface 51 that faces the recording material 12 with a predetermined gap (for example, about 0.5 to 2.0 mm). Common liquid chamber 53
An electrothermal converter (heat generating resistor, etc.) 55 for generating energy for ejecting ink is disposed along the wall surface of each liquid path 54 that communicates with each ejection port 52. The recording head 1 is mounted on the carriage 2 in such a positional relationship that the ejection ports 52 are arranged in a direction intersecting the moving direction (main scanning direction) of the carriage 2. In this way, the corresponding electrothermal converter 55 is driven (energized) based on the image signal or the ejection signal to cause the ink in the liquid path 54 to film-boil, and the pressure generated at that time causes the ink to be ejected from the ejection port 52. A recording unit (recording head) 1 is configured.

In FIG. 1, the recording material 12 is conveyed in the direction of arrow A by a conveying roller (not shown), passes between the upper guide 8a and the lower guide 8b, is registered by the registration roller pair 7a, and reaches the recording position. Be transported. The recorded recording material 12 is ejected by the ejection roller pair 7b.
At that time, the recording material 12 is guided to the sheet discharge port of the apparatus main body by the sheet discharge guide 9 on the bottom plate 11 of the main body. A recovery means (recovery unit) 10 is provided at a position outside the recording area on the bottom plate 11 of the main body. This recovery means 10 is provided immediately after the power is turned on, after being left for a certain period of time, or after recording a certain amount of data,
This is for sucking ink in the vicinity of the ejection port 52 of the recording head 1 and always maintaining the ejection port 52 in a good recordable state.

Next, the operation of the ink jet recording apparatus will be described. In FIG. 1, the recording material 12 is conveyed in the direction of arrow A by a conveying roller (not shown), passes between the upper guide 8a and the lower guide 8b, is registered by the registration roller pair 7a, and is then conveyed to the recording position. It Next, the timing belt 5 by the rotation of the stepping motor 4
The recording head 1 recovered by the recovery unit 10 along with the movement of 1 moves with the carriage 2 in the arrow B direction, and performs recording from the recording start position. When the carriage 2 moves to the recording end position (recording end position of each line), the stepping motor 4 is driven in reverse to move the recording head 1 in the direction of arrow C.

While the carriage 2 is moving in the direction of arrow C, the registration roller pair 7 is driven by a driving means (not shown).
a and the discharge roller pair 7b are rotated to convey the recording material 12 in the direction of arrow A by a predetermined amount, and wait for the next recording command.
That is, predetermined recording is performed on the recording material 12 by alternately repeating the movement of the carriage 2 (main scanning of the recording head 1) and the paper feeding of the recording material 12 (sub scanning).

Recording is completed by repeating a series of operations as described above, but in the prior art, in order to perform good recording, the carriage 2 is moved to the position of the recovery unit 10 for every fixed amount of recording. It is necessary to perform the recovery operation of the recording head 1, and the movement and the recovery operation for that purpose require a considerable amount of time. The present invention is intended to omit the movement time and the recovery operation time.

FIG. 3 is a sectional view schematically showing the structure near the ejection port of the recording head in the first embodiment of the ink jet recording apparatus to which the present invention is applied. In FIG. 3, the surface of the recording head 1 facing the recording material 12 (ejection port forming surface)
As described above, the 51 is provided with a large number of ejection ports 52. A first electrode 17 is provided inside each liquid path (nozzle) 54 communicating with each ejection port 52 so as to come into contact with the conductive ink 14. Each first electrode 17 is connected to the positive electrode of the power supply 19 via the control circuit 18.
The negative electrode of the power supply 19 is grounded. Each of the first electrodes 1
Reference numeral 7 is for charging the ink 14 ejected from each ejection port 52.

A second electrode 20 is provided near each discharge port 52. Each second electrode 20 is connected to the negative electrode of the power supply 22 via the control circuit 18. The positive electrode of the power supply 22 is grounded. Each of the second electrodes 20 is for adsorbing the ejected ink (ink droplet) 15. The second electrode 20 is attached to a position around each ejection port 52 by using, for example, the ejection port formation surface 51. In addition, the second electrode 20 is provided with an ink absorber 21 that is in contact with the second electrode 20.

In FIG. 3, during normal recording, the liquid path 54
When the electrothermal converter 55 (Fig. 2) inside is driven (energized),
A part of the ink 14 is heated and foams, and due to this foaming, ink droplets are ejected from the ejection port 52, and the ink droplets fly and land on the recording material 12. At this time, the control circuit 18 is in the off state, so that between the first electrode 17 and the power source 19 and between the second electrode 20 and the power source 22,
None of them are connected and electrically neutral, and the ink 14 is not charged.

Next, when the recording amount or the elapsed time reaches a level requiring a recovery operation, the positive electrode of the power source 19 is connected to the first electrode 17 and the negative electrode of the power source 22 is connected to the second electrode 20. After being connected, the ink 14 in the liquid path 54 becomes positively charged. The electrical connection at this time is performed in synchronization with the control for moving the carriage 2 to the position of the recovery means 10. That is, the reverse rotation signal input from the microcomputer to the stepping motor 4 in order to reverse the moving direction of the carriage 2 from the arrow B to the arrow C in FIG. 1 is also input to the control circuit 18. Be done. The recording amount required for the recovery operation can be set, for example, such that the recovery operation is performed once every eight shuttle recordings.

Then, before the carriage 2 reaches the recording start position, the electrothermal converters 55 of all the ejection ports 52 are driven to eject the ink droplets 15 from all the ejection ports 52. Since the ink droplet 15 has a positive charge as described above, the ink droplet 15 flies toward the second electrode 20, which is a negative electrode, and lands on the second electrode 20. The landed ink droplet 15 is absorbed by the ink absorber 21 provided on the second electrode 20 and spontaneously evaporates.

As a result, even within the recording area, the recovery operation can be performed at the timing when ink can be ejected from all the ejection ports 52, and the recovery operation is performed by the carriage 2.
Can be completed before reaching the recording start position. Therefore, it becomes possible to omit the moving time of the carriage 2 to the recovery means 10 and the time for the recovery operation, which are required in the prior art. In this embodiment, the same effect can be obtained if there is a potential difference between the first electrode 17 and the second electrode 20, so that the power supply 22 is omitted and the negative electrode of the power supply 19 is used as the second electrode. 20 (via control circuit 18). Further, the polarity (positive or negative) of the power source connected to the first electrode 17 and the second electrode 20 may be either, or may be the opposite polarity.

FIG. 4 is a sectional view schematically showing the structure near the ejection port of the recording head in the second embodiment of the ink jet recording apparatus to which the present invention is applied. In FIG. 4, the surface of the recording head 1 facing the recording material 12 (ejection port forming surface)
As described above, the 51 is provided with a large number of ejection ports 52. A first electrode 17 is provided inside each liquid path (nozzle) 54 communicating with each ejection port 52 so as to come into contact with the conductive ink 14. Each first electrode 17 is connected to the positive electrode of the power supply 19 via the control circuit 18.
The negative electrode of the power supply 19 is grounded. Each of the first electrodes 1
Reference numeral 7 is for charging the ink 14 ejected from each ejection port 52.

A second electrode 20 is provided near each discharge port 52. The second electrode 20 is connected to the negative electrode of the power supply 22 via the control circuit 18. The positive electrode of the power supply 22 is grounded. The second electrode 20 is for adsorbing the ejected ink (ink droplet) 15. The second electrode 20 is attached to a position around each ejection port 52 by using, for example, the ejection port formation surface 51. In addition, the second electrode 20 is provided with an ink absorber 21 that is in contact with the second electrode 20.

Therefore, in the embodiment of FIG. 4, the recording head 1 is provided with the third electrode 23 surrounding each ejection port 52 in a semi-annular shape. FIG. 5 is a partial front view showing an arrangement state of the second electrode 20 and the third electrode 23 around the ejection port 52 viewed from the recording material 12 side. The third electrode 23 is connected to the first electrode 17 as shown in FIG.

In FIG. 4, during normal recording, the liquid path 54
When the electrothermal converter 55 (Fig. 2) inside is driven (energized),
A part of the ink 14 is heated and foams, and due to this foaming, ink droplets are ejected from the ejection port 52, and the ink droplets fly and land on the recording material 12. At this time, the control circuit 18 is in the OFF state, so that between the first electrode 17 and the power source 19, between the third electrode 23 and the power source 19, and between the second electrode 20 and the power source 22. , None of them are connected and all electrodes are electrically neutral.
Is not charged.

Next, when the recording amount or the elapsed time reaches a level requiring a recovery operation, the positive electrode of the power source 19 is connected to the first electrode 17 and the third electrode 23, and the second electrode 20 is connected. The negative electrode of the power source 22 is connected to, and the ink 14 in the liquid path 54 becomes positively charged. The electrical connection at this time is performed in synchronization with the control for moving the carriage 2 to the position of the recovery means 10. That is, the reverse rotation signal input from the microcomputer to the stepping motor 4 in order to reverse the moving direction of the carriage 2 from the arrow B to the arrow C in FIG. 1 is also input to the control circuit 18. Be done. The recording amount required for the recovery operation can be set, for example, such that the recovery operation is performed once every eight shuttle recordings.

Then, before the carriage 2 reaches the recording start position, the electrothermal converters 55 of all the ejection ports 52 are driven to eject the ink droplets 15 from all the ejection ports 52. Since the ink droplet 15 has a positive charge as described above, the ink droplet 15 flies toward the second electrode 20, which is a negative electrode, and lands on the second electrode 20. The landed ink droplet 15 is absorbed by the ink absorber 21 provided on the second electrode 20 and spontaneously evaporates.

Further, satellites (positively charged) formed by being divided from the ejected ink droplets 15 tend to adhere to the vicinity of the ejection ports 52, but in the present embodiment, the satellites are surrounded so as to surround each ejection port 52. Since the polar third electrode 23 is provided, the satellite repels the third electrode 23. As a result, this satellite also has a second electrode 2
It is adsorbed by 0 and absorbed by the ink absorber 21. As a result, it is possible to prevent ink droplets from adhering to the vicinity of the ejection port 52, to make the recovery operation more reliable, and to further improve recording performance.

According to the embodiment shown in FIGS. 4 and 5, the recovery operation can be performed at the timing when ink can be ejected from all the ejection ports 52 even in the recording area. It will be possible to complete it before reaching. Therefore, it becomes possible to omit the moving time of the carriage 2 to the recovery means 10 and the time for the recovery operation, which are required in the prior art. Further, in the present embodiment, the third electrode 23 is provided at a position close to the ejection port 52 on the ejection port forming surface 51, and a voltage having the same polarity as that of the first electrode 17 is applied to the third electrode 23. With this configuration, satellites from the flying ink droplets 15 are prevented from adhering to the vicinity of the ejection port 52, and it is possible to improve the reliability of the recovery operation and further improve the performance of the recording operation.

In the embodiments of FIGS. 4 and 5, the same action and effect can be obtained if there is a potential difference between the first electrode 17 and the second electrode 20, so that the power source 22 is omitted. The negative electrode of the power supply 19 may be connected to the second electrode 20 (via the control circuit 18). Further, each electrode may be connected to a power source so that the first electrode 17 and the third electrode 23 have the same polarity and the second electrode 20 has the different polarity of the first and third electrodes. In that case, the positive and negative polarities may be either.

In the above-described embodiment, the serial type ink jet recording apparatus in which the recording head 1 is mounted on the carriage 2 has been described as an example, but the present invention is the whole area or a part of the recording material in the width direction. The present invention can be similarly applied to a line type ink jet recording apparatus that uses a line type recording head having a length to cover the above and performs recording only by sub-scanning, and similar effects can be obtained. The present invention also relates to a recording head and an ink tank (ink chamber).
In addition to the cartridge type that is integrated with, the recording head and the ink tank are separated and connected by an ink supply tube or the like, regardless of the arrangement of the recording head and the ink tank, The same can be applied and the same effect can be achieved.

Further, in the above-described embodiment, the color recording apparatus using a plurality of recording heads 1 for recording with different color inks has been described as an example, but the present invention is ink jet recording using one recording head. The same applies to any number of recording heads and inks used, such as an apparatus or a recording apparatus for gradation recording using a plurality of recording heads that record with inks of the same color and different densities, The same effect can be achieved.

The present invention can be applied to an ink jet recording apparatus that uses a recording means (recording head) using an electromechanical transducer such as a piezo element, but among them, thermal energy is used. In this way, an excellent effect can be obtained in an ink jet recording apparatus of the type that ejects ink. This is because such a system can achieve high density recording and high definition recording.

Regarding the typical structure and principle thereof, see, for example, US Pat. Nos. 4,723,129 and 4740.
This is preferably done using the basic principles disclosed in US Pat. No. 7,967. This method can be applied to both the so-called on-demand type and the continuous type, but particularly in the case of the on-demand type, a liquid (ink) is used.
By applying at least one drive signal to the electrothermal converter arranged corresponding to the sheet or liquid path holding the , The heat energy is generated in the electrothermal converter to cause film boiling on the heat acting surface of the recording means (recording head), and as a result, bubbles can be formed in the liquid (ink) in a one-to-one correspondence with this drive signal. So effective.

Due to the growth and contraction of the bubbles, the liquid (ink) is ejected through the ejection openings to form at least one droplet. It is more preferable to make this drive signal into a pulse shape, because the bubble growth and contraction are immediately and appropriately performed, so that the ejection of the liquid (ink) with excellent responsiveness can be achieved. As this pulse-shaped drive signal, US Pat.
Those described in US Pat. Nos. 4,633,359 and 4,345,262 are suitable. Incidentally, US Pat. No. 43131 of the invention relating to the rate of temperature rise of the heat acting surface
If the conditions described in No. 24 are adopted, even more excellent recording can be performed.

As the constitution of the recording head, in addition to the combination constitution of the discharge port, the liquid passage, and the electrothermal converter (the linear liquid passage or the right-angled liquid passage) as disclosed in the above-mentioned respective specifications. US Pat. No. 4,558,333 and US Pat. No. 4, which disclose a configuration in which a heat acting portion is arranged in a bending region.
The structure using the specification of 459600 is also included in the present invention. In addition, Japanese Laid-Open Patent Publication No. 123670/1984 discloses a configuration in which a common slit is used as a discharge portion of a plurality of electrothermal converters, and an opening for absorbing a pressure wave of thermal energy. The present invention is also effective as a configuration based on Japanese Patent Application Laid-Open No. 138461/1984, which discloses a configuration in which the above is associated with the discharge portion. That is, according to the present invention, recording can be reliably and efficiently performed regardless of the form of the recording head.

Further, as described above, 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 material (recording medium) which can be recorded by the recording apparatus. .. As such a recording head,
Either a configuration that satisfies the length by combining a plurality of recording heads or a configuration as one recording head integrally formed may be used. In addition, even with the serial type as in the above example, the recording head fixed to the device body,
Alternatively, a replaceable chip-type recording head that can be electrically connected to the device body and supply ink from the device body when mounted on the device body, or an ink tank is integrally provided on the recording head itself. The present invention is also effective when the above cartridge type recording head is used.

Further, it is preferable to add recovery means for the recording head, preliminary auxiliary means, etc. to the recording head provided in the present invention because the effects of the present invention can be further stabilized. Specifically, these are capping means, cleaning means, pressurizing or suctioning means, electrothermal converters or heating elements other than these, or preheating means for the recording head. It is also effective to perform stable recording by performing a preliminary discharge mode in which discharge different from recording is performed.

As described above, regarding the type and number of recording heads to be mounted, for example, only one is provided corresponding to a single color ink, or a plurality of recording heads having different recording colors and densities are provided. A plurality of inks may be provided corresponding to the ink. That is, for example, 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 either the recording head is integrally configured or a plurality of combinations may be used. The present invention is also extremely effective for a device provided with at least one of color colors or full colors by color mixing.

In addition, in the above-described embodiments of the present invention, the ink is described as a liquid, but it is an ink that solidifies at room temperature or lower and that softens or liquefies at room temperature, or an ink jet. In the method, the temperature of the ink itself is generally adjusted within a range of 30 ° C. or higher and 70 ° C. or lower to control the temperature of the ink so that the viscosity of the ink is within a stable ejection range. Any liquid may be used. in addition,
Whether the temperature rise due to thermal energy is positively used as the energy for changing the state of the ink from the solid state to the liquid state, or the ink that solidifies when left standing for the purpose of preventing ink evaporation is used. In any case, the ink is liquefied by applying the thermal energy according to the recording signal and the liquid ink is ejected,
The present invention is also applicable to the case of using an ink which has a property of being liquefied only by thermal energy, such as one which has already started to solidify when it reaches the recording medium.

The ink in such a case is described in JP-A-54-
As described in JP-A-56847 or JP-A-60-71260, a mode in which it is held as a liquid or a solid in a concave portion or a through hole of a porous sheet and faces the electrothermal converter. May be 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, as a form of the ink jet recording apparatus according to the present invention, in addition to the one used as an image output terminal of information processing equipment such as a computer, a copying apparatus combined with a reader or the like, and a facsimile apparatus having a transmitting / receiving function. It may be in the form of the above.

[0046]

As is apparent from the above description, according to the present invention, in the ink jet recording apparatus for recording by ejecting ink from the recording means to the recording material, the recording means is charged in order to charge the ejected ink. A first electrode provided at a position in contact with the ink inside, a second electrode provided at a position close to the ejection port of the recording unit for adsorbing the ejected ink, and the first electrode And a power source for applying a voltage to each of the electrodes so that a potential difference is generated between the second electrode and the second electrode. There is provided an ink jet recording apparatus capable of performing the recovery process of the recording means without requiring the time, and shortening the recording time.

According to another aspect of the present invention, in addition to the above configuration,
The third portion is provided at a position close to the ejection port on the ejection port formation surface of the recording unit.
The electrodes are provided, and the power is supplied to the first electrode and the third electrode.
In addition to the above effect, since the connection is made so that the voltage of the same polarity is applied to the electrode of and the voltage of the polarity different from that of the first and third electrodes is applied to the second electrode, (EN) An ink jet recording apparatus capable of more reliably performing a recovery operation by eliminating the adhesion of ejected ink to the vicinity of a satellite ejection port.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing a main configuration of an embodiment of an inkjet recording apparatus to which the present invention is applied.

FIG. 2 is a partial perspective view schematically showing the structure of an ink ejection portion of the recording means in FIG.

FIG. 3 is a schematic cross-sectional view showing a first embodiment of an electrode arrangement in the vicinity of a discharge port of a recording unit of an inkjet recording apparatus to which the present invention is applied.

FIG. 4 is a schematic cross-sectional view showing a second embodiment of the electrode arrangement in the vicinity of the ejection port of the recording means of the inkjet recording apparatus to which the present invention is applied.

FIG. 5 is a partial front view of the vicinity of the ejection port from the recording material side in FIG.

[Explanation of symbols]

 1 Recording Means (Recording Head) 2 Carriage 3 Guide Rail 4 Stepping Motor (Carriage Motor) 5 Timing Belt 7a Registration Roller 7b Paper Ejection Roller 10 Recovery Means (Recovery Unit) 11 Main Body Bottom Plate 12 Recording Material 14 Ink (in Liquid Channel) 15 Ink Droplet 17 First Electrode 18 Control Circuit 19 Power Supply 20 Second Electrode 21 Ink Absorber 22 Power Supply 23 Third Electrode 51 Discharge Port Forming Surface 52 Discharge Port 54 Liquid Path 55 Electrothermal Converter A Sub-scanning Direction (Paper feed direction) B Main scanning direction C Direction toward recovery means

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location B41J 2/05 9012-2C B41J 3/04 103 B

Claims (6)

[Claims] 1. An ink jet recording apparatus for recording by ejecting ink from a recording means to a recording material, wherein the first means is provided at a position in contact with the ink in the recording means in order to charge the ejected ink. An electric potential difference is generated between the electrode, the second electrode provided in the position close to the ejection port of the recording unit for adsorbing the ejected ink, and the first electrode and the second electrode. And an electric power source for applying a voltage to each electrode. 2. Between the first electrode and the power source and between the second electrode and the power source for applying the voltage of the power source to the first electrode and the second electrode. The ink jet recording apparatus according to claim 1, further comprising a control circuit. 3. A third electrode is provided at a position close to the ejection port on the ejection port formation surface of the recording means, and the power source is connected to the first electrode.
Are connected so that a voltage of the same polarity is applied to the second electrode and the third electrode, and a voltage of a different polarity from the first and third electrodes is applied to the second electrode. The inkjet recording apparatus according to claim 1. 4. The ink jet recording apparatus according to claim 3, wherein a control circuit is provided between the third electrode and the power source in order to apply the voltage of the power source to the third electrode. 5. The inkjet recording apparatus according to claim 1, wherein the recording means is an inkjet recording means including an electrothermal converter that generates thermal energy used for ejecting ink. 6. The ink jet recording apparatus according to claim 5, wherein the recording means ejects the ink from the ejection port by utilizing film boiling generated in the ink by the thermal energy generated by the electrothermal converter. ..