JP2818026B2 - Ink jet recording device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus that performs recording on a recording material by discharging ink from ink discharge ports.

[Related Art] Conventionally, this type of ink jet recording apparatus includes an ink droplet attached to a discharge surface of a recording head for discharging ink,
In order to remove dust and obtain stable printing and image recording, a wiper member made of rubber or the like is provided, and for example, it is configured to wipe the ink ejection surface of the recording head as necessary before and after the recovery operation. Are often used.

In particular, in a serial printer in which recording is performed by scanning a recording head in a direction perpendicular to the sheet feeding direction, a wiper member disposed near an end of a platen holding a recording material moves during wiping. A system in which the head is ejected toward the head and the ink ejection surface of the head is wiped using the moving speed of the carriage has been widely used because of its low cost and high reliability. For example, JP
Japanese Unexamined Patent Application Publication No. 9-94472 has a wiping (wiper) member that moves forward and backward with respect to the recording head, and reduces the carriage speed when the recording head is guided to the wiping position. An apparatus in which the contact speed is reduced is disclosed. By appropriately reducing the carriage moving speed in this manner, it is possible to ensure the contact state between the wiper member and the recording head.

[Problems to be Solved by the Invention] However, in the above-described conventional example, when the recording head is wiped by the wiper member, both contact states do not change, and only the relative speed changes. When the wiper member comes off the ink ejection surface of the head in the final stage, the ink wiped from the tip of the wiper member may be splashed and splashed to the surroundings, and the splash may stain the recording sheet or the apparatus. Was.

SUMMARY OF THE INVENTION An object of the present invention is to provide an ink jet recording apparatus that can suppress the splash of ink when a head is wiped by a wiper member in order to solve the conventional problems described above. Is to do.

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a method for recording on a recording material arranged in a recording area by discharging ink from an ink discharge port of an ink jet recording head. In the ink jet recording apparatus, the wiper member having elasticity for slidably touching the ink discharge surface provided with the ink discharge ports and wiping the ink discharge surface, and the ink jet recording head and the wiper member are relatively positioned. Moving means for moving to, the control means to vary during the wiping the amount of the wiper member slidable contact with the ink ejection surface during the wiping, the control means,
When the relative movement direction of the ink jet recording head with respect to the wiper member is toward the recording area, the amount of engagement between the wiper member and the ink ejection surface is reduced at least immediately before the wiper member separates from the ink ejection surface. Control as described above.

[Operation] According to the present invention, during the wiping operation of the ink ejection surface by the wiper member, the amount by which the tip end of the wiper member engages with the ink ejection surface (hereinafter referred to as the amount of entry) for the sliding contact is controlled by the control means. The wiper member reduces the amount of entry at least immediately before the wiper member separates from the ink ejection surface, whereby the recoil due to the elasticity of the wiper member when the wiper member separates from the ink discharge surface The ink can be scattered to the surroundings to prevent the recording material and peripheral devices from being stained.

[Example] Hereinafter, an example of the present invention will be described in detail and specifically with reference to the drawings.

FIG. 1 shows an example of a facsimile apparatus to which the present invention is applied as one embodiment. The facsimile apparatus according to the present embodiment is roughly classified on this drawing, as shown by a two-dot chain line, as shown by a document conveying system A, an optical system B, a power supply section C, an electric circuit board D, a recording paper conveying system E, It is composed of a system F, a supply system G and a recovery system H. Here, the document transport system A and the optical system B constitute a document reading unit for reading a document image from the document 1. As a basic operation of the facsimile apparatus, the document feeder of the document transport system A is used for transmission or copying. Manuscript 1 to 2
Is set, the original 1 is conveyed in the direction of the arrow by a roller row (rollers R1, R2, R3, R4) driven by a driving unit (not shown). Then, at a predetermined original reading line (main scanning line) position in the middle of the conveyance, the original information is transmitted from the original 1 to the line CCD3 by the condenser lens Le via the reflection optical path of the optical system B (lamp L1, mirrors M1, M2). And converted into an electric signal by the line CCD3 and read.

When receiving or copying, the sheet transport system E
, The recording sheet 4 wound in a roll shape is sequentially conveyed by a row of rollers driven by driving means (not shown) along a path indicated by a thick line, and the document information is recorded on a recording line determined in the middle of the conveying path. The ink is ejected from the ejection openings of the head unit 5 based on the information, and recording is performed. The ejection of the ink from the head unit 5 is as follows.
This is performed by a so-called bubble jet method in which bubbles are generated in ink using heat generated by an electrothermal converter (not shown), and the ink is ejected by a change in pressure of the bubbles.

Further, the power supply section C supplies an input of an AC power supply from the outside to supply power to a necessary portion. The electric circuit board D includes a circuit, which will be described later, for controlling the function and operation of each part of the apparatus, mainly a microcomputer system. I / O circuit. Supply system G is head unit 5
The recovery system H includes a cleaning unit and a capping unit necessary for causing the head unit 5 to perform stable ejection.

Next, the recovery system H and the decal system F according to this embodiment are used.
1 and 2 will be described with reference to FIG. 1 and FIG. Here, the head unit 5 is a so-called full line head in which ink ejection ports are arranged over the entire recording width of the recording sheet 4, and is formed to be elongated in the vertical direction with respect to the paper surface, and the whole is rotated around the head axis 5B. It is movably supported. In FIG. 1, 7 is a head shaft 5B.
Is a stepping motor for rotating the head unit 5 around, and 8 is a belt for driving the stepping motor.

Also, 10 is a recovery system H for the head unit 5 described above.
And a cap unit that performs capping and wiping operations on the head unit 5. The cap unit 10 is provided with a cap member 11 and a wiper member 12 that are long enough to cover the ink ejection surface 5A of the head unit 5 at positions as shown in FIG. It is swingably supported by a frame shaft 13 attached to one end.

The swing operation of the cap unit 10 is performed by the frame shaft 13.
The stepping motor 7 for rotating the head unit 5 and the stepping motor for driving the cap unit 10 are both driven by control means described later. The speed is controlled together with the timing.

FIG. 3 shows a control system of the ink jet recording apparatus according to the present invention. Reference numeral 21 denotes a central processing unit (CPU), which includes a timer and the like. The CPU 21 performs document reading and recording by the head unit 5 and controls various operations by the above-described recovery system H. That is, 22 is a ROM in which control procedures and the like in each mode of the apparatus are stored, and 23 is an RA used for reading from the original 1 and storing recording data.
M. Therefore, the CPU 21 drives the document transport system A and the sheet transport system E in accordance with an instruction input from an operation panel (not shown) or the like, and also controls the document reading unit (optical system) B to copy the original 1.
Further, the head driver 24 is driven based on the read information, and ink is ejected from the head unit 5 to perform recording.

When capping is performed on the head unit 5 after recording, or when the head unit 5 performs an operation for recovery, the head shaft driving motor (stepping motor) 7 is driven via the driver 25 in a procedure described later. Then, the drive of the frame axis drive motor 27 is controlled via the driver 26.

Hereinafter, the control operation at that time will be described with reference to FIG. 4 together with the procedure with reference to FIG. 2 and FIG.

First, the capping state of the unused head unit 5 at the time of non-recording is not shown in these figures, but the head unit 5 is at the position shown in FIG. The ink ejection surface 5A of the head unit 5 is kept covered. Thus, for example, when an operation of forcibly discharging ink along with bubbles from the ink discharge port provided on the ink discharge surface 5A is performed as a recovery operation, the ink remaining on the ink discharge surface 5A is then wiped off Since it is necessary, the wiping operation by the wiper member 12 is performed as follows.

First, in FIG. 2, (A) shows the retracting operation of the cap unit 10. The rotation in the direction of the arrow is performed by a motor (stepping motor) 27 for driving the frame axis.
In step S1, the CPU 21 drives the cap unit 10 to separate the cap member 11 from the ink ejection surface 5A of the head unit 5 in accordance with the procedure shown in FIG.

Next, in step S2, the stepping motor 7 is driven, and as shown in FIG. 2B, the head unit 5 is guided to the wiping position by the wiper member 12, and in step S3, the cap unit 10 is moved in the direction of the arrow, ie, (A). The wiper member 12 is moved from the position shown in FIG.
Drive in the direction to approach the wiper member in step S4
It waits for 12 to come into contact with the ink ejection surface 5A of the head unit 5. Then, in step S5, wiping is performed.
The state of (B) is confirmed by the timer of 1
Further, when it is confirmed that the ink discharge port array (not shown) has been wiped as shown in FIGS. 5A and 2C, the process proceeds to step S6. Here, the cap unit 10 is moved relative to the head unit 5 at a semi-retreat position (FIG. 5B) where the amount (entry amount) 30 relating to the ink ejection surface 5A at the tip of the wiper member 12 is reduced. Move.

That is, as shown in FIG. 5 (B), the amount of intrusion 30 protruding for sliding contact with the ink ejection surface 5A of the wiper member 12 is reduced, and the wiper member 12 is separated from the ink ejection surface 5A. Occasionally, it is possible to prevent the splash of ink from splashing around due to the sudden rebound of the wiper member 12. In particular, in this embodiment, the wiper member
12 is located at a position distant from the recording sheet 4, and furthermore, by making the wiping direction coincide with the recording direction by the head unit 5, the rebound direction of the wiper member 12 is different from the side on which the recording sheet 4 is held. Since the head unit 5 is moved from the cap member 11 side to the recording area side, the recording sheet 4 is not contaminated, and the surrounding members can be prevented from being contaminated.

Then, when the wiping is completed, the cap unit 10 is rotated to the retracted position as shown in FIG.
S7) Then, if it is confirmed in step S8 that the head unit 5 has been guided to the recording position by a sensor or the like (not shown), the rotation of the head unit 5 is stopped in step S9, and a series of wiping is performed. The operation ends.

In the above description, the wiping operation that is continuously performed after the rotation operation for forcibly ejecting the ink from the ink ejection surface has been described. However, such a wiping operation is performed immediately before the start of printing or during the printing. This operation is also performed for the purpose of removing the ink ejection surface due to the adhesion or dust that has accidentally adhered. The operation procedure at that time is the same as that described above, and a description thereof will be omitted.

In addition, as in the above-described embodiment, the ink ejection surface 5A
Is performed while the head unit 5 rotates upward from the cap position to reach the recording position, so that the angle at which the wiper member 12 can be separated from the ejection surface 5A is small and the resistance is small. Therefore, even if a small amount of ink droplets remain on the ink ejection surface 5A, the remaining ink droplets will be located downstream of the ejection openings when the head unit 5 moves to the recording position. Even if the droplets flow, they are separated from the ejection port portion, so that there is no adverse effect on recording.

Further, in the embodiment described above, when rotating the cap unit, the rotation position was controlled, but the cap unit is kept at a predetermined wiping position on the way,
It is also possible to cause the head unit to perform a corresponding operation and perform a relative position control operation.
Still further, the application of the present invention is not limited to the case where a full-line type ink jet recording head is used, but may be applied to a case where a wiping operation is performed by rotating a recording head or a wiper. For example, it goes without saying that the present invention can be widely applied to a serial type recording apparatus in which a recording head is mounted on a carriage and recording is performed by traveling.

As described above, the present invention brings about an excellent effect particularly in a recording head and a recording apparatus of a bubble jet system among ink jet recording systems. This is because according to such a method, it is possible to achieve higher density and higher definition of recording.

As for the representative configuration and principle, it is preferable to use the basic principle disclosed in, for example, US Pat. Nos. 4,723,129 and 4,740,796. This method can be applied to both the so-called on-demand type and the continuous type. In particular, in the case of the on-demand type, it is arranged corresponding to a sheet or a liquid path holding a liquid (ink). Applying at least one drive signal corresponding to the recording information and providing a rapid temperature rise exceeding nucleate boiling to the electrothermal transducer, thereby causing the electrothermal transducer to generate thermal energy, thereby causing the recording head to emit heat energy. This is effective because a film in the liquid (ink) corresponding to the driving signal can be formed one by one by causing film boiling on the heat acting surface. 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. U.S. Pat. No. 44
Those described in JP-A-63359 and JP-A-4345262 are suitable. Further, when 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 a configuration of the recording head, in addition to a 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 specifications, A configuration using U.S. Pat. No. 4,558,333 and U.S. Pat. No. 4,459,600, which disclose a configuration in which is disposed in a bending region, is also included in the present invention. In addition, Japanese Unexamined Patent Publication No. 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, as a recording head having a length corresponding to the maximum width of a recording medium on which a recording apparatus can record, a configuration that satisfies the length by a combination of a plurality of recording heads, or a single recording head integrally formed is used. Any of the above configurations may be used.

In addition, even with a serial type, a recording head fixed to the apparatus main body, or an exchangeable print head that can be electrically connected to the apparatus main body or supplied with ink from the apparatus main body when attached to the apparatus main body. The present invention is also effective when a chip type recording head or a cartridge type recording head in which an ink tank is provided integrally with the recording head itself is used.

Further, it is preferable to add recovery means for the print head, 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. Specifically, in addition to the capping means and the cleaning means for the recording head, a pressure or suction means, an electrothermal converter, a separate heating element, or a backup element using a combination thereof. It is also effective to carry out a preliminary ejection mode in which a heating means or the like is provided and an ejection is performed separately from the printing to perform stable printing.

Regarding the type or number of print heads to be mounted, for example, in addition to one provided for single color ink, a plurality of print heads are provided corresponding to a plurality of inks having different print colors and densities. May be used. 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 that solidifies at or below room temperature and softens or liquefies at room temperature, or the ink itself in an inkjet method. In general, the temperature 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. I just need. In addition, the temperature rise due to thermal energy can be positively prevented by using it as energy for changing the state of the ink from a solid state to a liquid state, or ink that solidifies in a standing state to prevent evaporation of the ink can be used. In any case, the ink is liquefied by the application of the thermal energy according to the recording signal, and the ink is liquefied and ejected, or when the ink reaches the recording medium, it begins to solidify. The present invention is also applicable to a case where an ink that liquefies for the first time by energy is used. The ink in such a case is disclosed in
No. -56847 or JP-A-60-71260, while being held as a liquid or solid substance in a porous sheet recess or through hole, facing the electrothermal converter. It is good also as a form. 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, the form of the ink jet recording apparatus of the present invention may be used as an image output terminal of an information processing apparatus such as a computer, a copying apparatus combined with a reader or the like, or a facsimile apparatus having a transmission / reception function. Or the like.

[Effects of the Invention] As described above, according to the present invention, an ink jet recording apparatus performs recording on a recording material arranged in a recording area by discharging ink from an ink discharge port of an inkjet recording head. In the recording apparatus, a wiper member having elasticity for slidably contacting an ink ejection surface provided with the ink ejection port and wiping the ink ejection surface, and relatively moving the ink jet recording head and the wiper member Moving means for changing the amount of the wiper member, which is in sliding contact with the ink ejection surface, with the ink ejection surface during wiping, the control means comprising: When the relative movement direction with respect to the wiper member is toward the recording area, at least immediately before the wiper member separates from the ink ejection surface. Since the amount of engagement between the wiper member and the ink ejection surface is controlled to be reduced,
It is possible to prevent the ink from scattering from the wiper member and contaminating the surroundings, and to prevent troubles such as disturbing the electric wiring and the reading optical system of the apparatus and soiling the recording material.

In addition, since it is possible to perform wiping with less ink scattering while maintaining a high driving speed, there is no need to reduce the overall speed for wiping. This is suitable for the case where the time required for the wiping operation is restricted by the modification.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of the configuration of a facsimile apparatus to which the present invention is applied, FIG. 2 is an explanatory diagram of a wiping operation according to the present invention, and FIG. 3 is a block diagram showing the configuration of a control circuit according to the present invention. FIG. 4 is a flowchart showing a procedure of a control operation at the time of wiping according to the present invention. FIG. 5 is an explanatory diagram of an operation for varying the amount of approach to the ink ejection surface according to the present invention. 4 ... recording sheet, 5 ... head unit, 5A ... ink ejection surface, 5B ... head shaft, 7 ... (for driving head shaft) stepping motor, 10 ... cap unit, 11 ... cap member, 12 ...... Wiper member, 21 ... CPU, 22 ... ROM, 23 ... RAM, 24-26 ... Driver, 27 ... (for driving the cap unit) Stepping motor, 30 ... Penetration amount (ink ejection of wiper member) Amount related to surface).

Claims (5)

(57) [Claims] 1. An ink jet recording apparatus which performs recording on a recording material by discharging ink from an ink discharge port of an ink jet recording head onto a recording material arranged in a recording area, wherein the ink provided with the ink discharge port is provided. A wiper member having elasticity for slidably contacting the ink ejection surface by slidably contacting the ejection surface; moving means for relatively moving the ink jet recording head and the wiper member; and slidably contacting the ink ejection surface Control means for varying the amount of the wiper member associated with the ink ejection surface during the wiping operation, the control means comprising: At least immediately before the wiper member separates from the ink ejection surface, An ink jet recording apparatus characterized by controlling so as to reduce the amount of each other instead. 2. An ink jet recording apparatus according to claim 1, wherein said moving means is capable of moving said wiper member in a direction approaching and separating from said ink jet recording head. 3. The ink jet recording head according to claim 1, wherein said moving means is capable of moving said ink jet recording head between said recording area and an area where said wiper member is arranged.
3. The ink jet recording apparatus according to claim 1. 4. The ink jet recording head is of a full line type in which the ink discharge ports are arranged corresponding to a maximum width of a recording material on which the ink jet recording apparatus can record, and the moving means includes: The inkjet recording apparatus according to claim 1, wherein the inkjet recording head is rotatable between a recording area and an area where the wiper member is arranged. 5. The ink-jet recording head according to claim 1, further comprising an electrothermal converter for generating thermal energy used to cause the ink to be ejected from the ink ejection port by causing a state change in the ink. The ink jet recording apparatus according to any one of claims 1 to 4, wherein: