JP2001215904A - Electronic blackboard - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electronic blackboard of a recording system with which repetitive writing and erasing of images may be carried out by attaining the compatibility of image releasability with image fixability of a belt-like recording medium, a wiping roller for erasing the images may be easily refreshed and wiped waste ink may be easily recovered. SOLUTION: An erasing engine 7 for erasing the images written in the belt- like recording medium 1 is provided with the wiping roller 21 stuck with a cloth material for wiping the images and a dressing roller 22 formed by sticking cloth of electrostatically flocked chemical fibers to its surface in order to scrape off the ink sticking onto the wiping roller 21. The belt-like recording medium 1 and the wiping roller 21 as well as the wiping roller 21 and the dressing roller 22 are respectively brought into rolling contact with each other respectively in opposite directions.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electronic blackboard having a writing engine for writing an image on a belt-shaped recording medium by a recording means and an erasing engine for erasing an image written on the belt-shaped recording medium.

[0002]

2. Description of the Related Art In general, an electronic blackboard writes an image (including characters and symbols) on a white board made of a belt-shaped recording medium that can be transported and moved, displays the image, and moves the belt-shaped recording medium while moving the belt-shaped recording medium. It is configured to delete the image, and can be used for a message board, an advertisement display, and the like. Such electronic blackboards can be roughly classified into two types. One is to print out handwritten characters using a whiteboard marker pen, and the other is to output computer output characters etc. in a whiteboard form. This is displayed on a display medium (recording medium).

[0003] The present invention belongs to the latter electronic blackboard, and there are two types of conventional products of this type, one using a magnetism stylus technology and one using a liquid crystal. The electronic blackboard using the magnestylus technology forms a toner image by electrostatically attracting a conductive magnetic toner to a belt-shaped endless sheet, moves the sheet to display the toner image, and displays the toner image. The toner image is erased by removing the electrostatic force from the sheet.

[0004] Recording means (inkjet head)
There is also proposed an electronic blackboard of a recording system (inkjet recording system) configured to form an image by discharging ink onto a recording medium (display sheet) in the form of an endless belt.
Known documents disclosing such an ink-jet recording type electronic blackboard include, for example, JP-A-8-106261 and JP-A-8-310078. In such a conventional ink-jet type electronic blackboard, since water-soluble ink is used for image formation (image writing), paper or a water-soluble polymer is used as a liquid absorbing layer (liquid receiving layer) in a display sheet. Used.

[0005]

However, there is a technical problem in the electronic blackboard using the above-mentioned magnetism stylus technique that it is difficult to colorize it because monochrome magnetic materials are repeatedly reused. Further, an electronic blackboard using the liquid crystal has a low contrast on a display surface and has a viewing angle characteristic (inconsistency due to a viewing angle), and further requires a backlight or a memory (recording). There is also a technical problem that a relatively large power consumption is required to hold the display due to lack of holdability.

Further, in the above-described conventional electronic blackboard, especially in the conventional ink-jet type electronic blackboard, a recording medium (display) having a liquid absorbing layer (liquid receiving layer) such as paper or a water-soluble polymer as described above. Since the use of the sheet) makes it difficult to reuse the recording medium, the ink and the recording medium become consumables, and there are technical problems to be solved in terms of cost, maintenance, and ecology. Specifically, since it is necessary to use a recording medium without a liquid receiving layer in order to reuse the recording medium, both the fixing property of the ink to the recording medium and the peeling property of the ink image from the recording medium are compatible. Need to be done.

That is, since the solvent in the ink exists on the surface of the recording medium while having fluidity, a structure for preventing the recorded image (written image) from bleeding is required. Further, it is necessary to have a configuration that can easily and completely erase a recorded image. Such technical problems have not been solved in the electronic blackboard described in the above-mentioned Japanese Patent Application Laid-Open Nos. 8-106261 and 8-310078, which are exemplified as known documents.

The present invention has been made in view of the above-mentioned conventional technical problems, and an object of the present invention is to provide an image fixing property (ink fixing property) and an image releasability (ink releasability) of a belt-shaped recording medium. Can be written and erased repeatedly on the belt-shaped recording medium, and can be written repeatedly by refreshing the writing surface of the belt-shaped recording medium. An object of the present invention is to provide an electronic blackboard of a recording system capable of easily collecting wiped waste ink.

[0009]

Means for Solving the Problems The present invention (claim 1) provides:
In order to achieve the above object, an electronic blackboard including a writing engine for writing an image on a belt-shaped recording medium by a recording unit and an erasing engine for erasing an image written on the belt-shaped recording medium, wherein the erasing engine is It has a wiping roller for wiping an image written on a belt-shaped recording medium, and a dressing roller for scraping off ink attached to the wiping roller.

According to a second aspect of the present invention, in addition to the configuration of the first aspect, the recording means is an ink jet recording means for writing an image by discharging ink, the belt-shaped recording medium and the wiping roller. A configuration in which the wiping roller and the dressing roller are in rolling contact with each other in the opposite direction, the wiping roller is formed of a cylindrical member to which a wiping cloth is attached, and the dressing roller is a circle formed by a brush. A configuration comprising a columnar member, the wiping cloth material is a woven fabric, a raised cloth, a velvet or a non-woven fabric, the brush is a spiral brush, and the dressing roller is a brush made of a synthetic fiber such as polyester or nylon on the surface of the brush. The recording means is a columnar member to which an electrostatically-flocked cloth is attached, and the recording means is capable of writing a full-color image. The above object can be achieved more efficiently by employing a configuration that is a jet recording unit, or a configuration in which the inkjet recording unit is provided with an electrothermal converter that generates thermal energy used for discharging ink. Things.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a side sectional view showing a schematic structure of a first embodiment of an electronic blackboard to which the present invention is applied.
3 is a front view of the display surface as viewed from an arrow 2-2 in FIG. 1, and FIG. 3 is a cross-sectional view of the back surface as viewed from an arrow 3-3 in FIG. Hereinafter, embodiments of the present invention will be described using an electronic blackboard having a writing engine of an inkjet recording system as an example. FIGS. 1 to 3 exemplify an electronic blackboard (full-color electronic blackboard) provided with an inkjet head capable of writing a full-color image using inks of a plurality of colors (for example, cyan, magenta, yellow, and black).
The electronic blackboard shown in FIGS. 1 to 3 is configured such that a belt-shaped recording medium 1 having a display surface on which an ink image is to be written is conveyed up and down as indicated by arrows.

1 to 3, reference numeral 1 denotes a belt-shaped recording medium having a display surface (display screen) formed of an ink-impermeable belt material and on which an ink image is written, and 2 denotes a sub-scan of the belt-shaped recording medium 1. A recording medium sub-scanning means (sub-scanning means) for transporting and traveling in the direction, an image forming means composed of a plurality of ink-jet heads (ink-jet recording means, recording means) 3 as image writing means; An inkjet head main scanning means (main scanning means) (not shown) for reciprocating with respect to the belt-shaped recording medium 1 in a main scanning direction crossing the sub-scanning direction is supplied to each of the plurality of inkjet heads 3. An ink storage means comprising a plurality of ink cartridges for storing ink;
And ink supply means for supplying ink to each ink jet head 3 from.

1 to 3, the ink-jet head (image forming means, recording means) 3, the ink cartridge (ink storing means) 5, and the ink supply means 6
Is mounted on a carriage 9 which is guided and supported so as to be able to reciprocate along a guide rail 11, and the carriage 9 and these mounted components constitute a writing engine 10 capable of main scanning. Reference numeral 7 denotes an erasing engine for erasing an image written on the recording medium 1. Below the erasing engine 7, as will be described later with reference to FIG. 9, a waste ink collecting means 8 (not shown) for collecting ink (waste ink) scraped from the recording medium 1 for erasing an ink image. (Refer to the waste ink collection tray 23 in FIG. 9).

In the illustrated electronic blackboard, the belt-shaped recording medium (display surface forming member, display sheet) 1 is constituted by an endless belt. Instead of this, a reciprocating belt having winding mechanisms at both ends is used. You may comprise. Also,
The belt-shaped recording medium 1 is formed of an ink-impermeable belt (sheet material), and has a display surface (recording surface).
Is preferably white.For example, plastics such as polyethylene terephthalate mixed with white pigment, acrylic hard coat, fluorine coat, silicone coat, etc. on the front surface, and functional layers with various purposes laminated on the back surface Can be used.

The ink-jet head (ink-jet recording means) 3 is an image forming means for performing writing by selectively discharging ink from a plurality of discharge ports by applying energy in accordance with an image signal. The ink jet head 3 is an image forming unit that discharges ink by using thermal energy, and includes an electrothermal converter for generating thermal energy. Further, the inkjet head 3 causes a pressure change due to growth and shrinkage of bubbles due to film boiling generated by the thermal energy applied by the electrothermal transducer, and the ink is ejected from an ejection port using the pressure change. Thus, an ink image is formed. The electrothermal transducer is disposed corresponding to each of the ejection ports, and ejects ink from the corresponding ejection port by applying a pulse voltage to the corresponding electrothermal transducer in accordance with an image signal. Things.

FIG. 7 is a partial perspective view schematically showing the structure of an ink ejection section (one ejection port array) of the ink jet head 3. As shown in FIG. In FIG. 7, a plurality of discharge ports 82 are formed at a predetermined pitch on a discharge port surface 81 facing the belt-shaped recording medium 1 at a predetermined interval (for example, about 0.3 to 2.0 mm). An electrothermal converter (heating resistor, etc.) 85 that generates thermal energy for ink ejection is arranged along the wall surface of each liquid path 84 that communicates the common liquid chamber 83 and the ejection port 82. The ink jet head 3 is mounted so that the discharge ports 82 are arranged in a direction crossing the main scanning direction (in this embodiment, the moving direction of the carriage 9 mounted on the carriage 9). In this manner, the corresponding electrothermal transducer 85 is driven (pulse voltage is applied) based on the image signal or the ejection signal to cause the ink in the liquid passage 84 to boil, and the pressure generated at that time causes the ink from the ejection port 82 to be discharged from the ejection port 82. An inkjet head 3 for discharging droplets is configured.

In FIG. 1, an endless belt-shaped recording medium 1 has at least two rollers 12 as shown in FIG.
13, a predetermined tension is applied,
On the other hand, the roller is driven by the recording medium sub-scanning means 2 to be conveyed (sub-scanning) and moved in a predetermined direction.
In the case of an endless belt, since seamless processing is required, the cost generally increases. Therefore, in consideration of cost and the like, a reciprocating belt in which winding mechanisms are provided at both ends of the belt-shaped recording medium may be used. In the case of using this take-up (reciprocating) belt-shaped recording medium, both ends of the belt-shaped recording medium are fixed to two rollers, wound around one rotating roller, and sent out from the other roller. Thus, the recording medium is conveyed (sub-scan). In this case, when the belt is completely wound, the operation is performed so that the rotation of the roller is reversed to return to the initial state.

The position where the ink-jet head 3 is disposed is a non-display position on the upstream side of the display portion of the electronic blackboard in the sub-scanning direction when viewed from the conveying (sub-scanning) movement direction of the belt-shaped recording medium 1 comprising the endless belt. Is selected as a part that is easy to maintain. The inkjet head 3 is mounted on a carriage 9 that is guided and supported reciprocally along a guide rail 11 installed in a direction (width direction of the belt-shaped recording medium 1) orthogonal to the conveying direction of the belt-shaped recording medium 1. The main scanning movement is performed by driving the carriage 9. This main scanning movement may be performed by omitting the carriage 9 and directly moving the inkjet head 3 along the guide rail 11.

As the color ink used in the ink jet head 3 of the electronic blackboard according to the present invention, a polymer emulsion is added to secure the fixability, and a pigment ink is used to secure the releasability.
That is, a pigment ink to which a polymer emulsion is added is used. The reason why the fixability is improved by using such a pigment ink is as follows. That is, as the polymer emulsion, an acrylic emulsion or a vinyl acetate emulsion in which a water-insoluble polymer is dispersed in a solvent mainly containing water is preferable. On the other hand, if a water-soluble polymer is added to a dye ink, the viscosity of the ink may increase to make it impossible to eject the ink. Therefore, it is necessary to add a small amount of the water-soluble polymer to the inkjet ink.

On the other hand, since an ink having a low viscosity can be obtained even when a high concentration is added to the emulsion, it can be ejected by ink jet. Further, the polymer emulsion interacts with the hydrophobic surface of the above-mentioned belt-shaped recording medium immediately after writing (printing, recording) and is easily adsorbed. Although this adsorption force is extremely weak, when the glass transition point of the polymer emulsion is in the range of about 0 degrees Celsius or less (under normal use conditions), the adhesive force to the recording medium surface acts,
The recorded image (written image) can be prevented from flowing before the ink solvent dries. Further, as the solvent evaporates, the emulsion polymer particles come into contact with each other to form a film, whereby the fixability can be further enhanced. This film formation contributes to the releasability of the ink image and also to the improvement of the erasing function when erasing the written image.

An erasing engine 7 for erasing an ink image from the display surface of the belt-shaped recording medium 1 wipes and removes the aforementioned peelable ink from the display surface (screen) of the belt-shaped recording medium 1 by a wiping roller. The dressing roller is refreshed by further scraping off the waste ink transferred (adhered) to the wiping roller by the wiping removal by the dressing roller. Further, by making the dressing roller using a low-density brush material, the amount of waste ink taken into the dressing roller itself is minimized, the contamination is minimized, and ink is refilled (ink cartridge replacement). Except for, a maintenance-free wiping erasure mechanism (erase engine) is configured.

FIG. 4 is a plan sectional view showing a schematic structure of a second embodiment of an electronic blackboard to which the present invention is applied, and FIG. 5 is a front view of the display surface viewed from an arrow 5-5 in FIG. FIG. 6 is a side cross-sectional view taken along line 6-6 in FIG. FIG.
6 also illustrate an electronic blackboard (full-color electronic blackboard) provided with an inkjet head capable of writing a full-color image using inks of a plurality of colors (for example, cyan, magenta, yellow, and black).

The second embodiment shown in FIGS. 4 to 6 relates to a horizontally long full-color electronic blackboard in which the belt-shaped recording medium 1 is conveyed and moved in the horizontal direction. As shown in FIG. 4, the writing engine 10 having the inkjet head 3 is disposed on the right side of the belt-shaped recording medium 1 in the drawing.
An erasing engine 7 for erasing a written image (ink image) on the recording medium is disposed on the left side of the belt-shaped recording medium 1 in the drawing. The electronic blackboard according to the second embodiment is equivalent to the electronic blackboard according to the above-described first embodiment which is placed horizontally so as to convey and move the belt-shaped recording medium 1 in the horizontal direction. The same reference numerals are used to denote the same parts, and their detailed description is omitted.

FIG. 8 is a schematic diagram showing an arrangement of a writing engine and an erasing engine of an electronic blackboard to which the present invention is applied, together with a belt-shaped recording medium. FIG. 9 is an embodiment of an erasing engine of an electronic blackboard to which the present invention is applied. It is a typical sectional view showing composition of. In FIG. 8, an endless belt type belt-shaped recording medium 1 is wound around two rollers 12 and 13 arranged at a predetermined interval inside the electronic blackboard. The roller 12 or 13 is conveyed and moved in the direction of the arrow by rotationally driving. One end of the belt-shaped recording medium 1 (the roller 12 side in the illustrated example)
Is provided with a writing engine 10, and the other end (in the illustrated example, on the roller 13 side) is provided with an erasing engine 7. Generally, it is preferable for both engines that the distance between the writing engine and the erasing engine be as large as possible as shown in FIG. 8 in consideration of dust generation and ink contamination.

In FIG. 9, the erasing engine 7 includes a wiping roller 21 for wiping the ink image written on the belt-shaped recording medium 1 and a dressing roller 22 for scraping off the ink attached to the wiping roller. Have
A waste ink recovery tray 23 is provided below these rollers 21 and 22. The belt-shaped recording medium 1 and the wiping roller 21 roll in opposite directions in a state of contact with a predetermined pressure, and the wiping roller 21 and the dressing roller 22 roll in opposite directions with a contact of the predetermined pressure. It is configured to be. Each rotation (rolling) direction is as shown by an arrow.

In FIG. 9, the wiping roller 21 is composed of a cylindrical member to which a wiping cloth is adhered, and the dressing roller 22 is composed of a cylindrical member formed of a brush. As the wiping cloth material, for example, a woven fabric, a raised cloth, a velvet, a nonwoven fabric, or the like is used.
A spiral brush is used as the brush, and the dressing roller 22 is formed of a columnar member in which a cloth in which chemical fibers such as polyester or nylon are electrostatically planted is adhered to the surface of the brush.

8 and 9, when the drive (conveyance) of the belt-shaped recording medium 1 forming the display screen is started by the rotation of the recording medium sub-scanning means 2, the writing by the writing engine 10 is performed. At the same time, the erasure by the erasure engine 7 starts. At that time, in the erasing engine 7, the wiping roller 21 is rotationally driven in a direction opposite to the moving direction of the belt-shaped recording medium 1, so that the wiping of the ink image on the recording medium 1 starts. The rotation speed (peripheral speed) of the wiping roller 21 is set to a speed opposite to the moving speed of the belt-shaped recording medium 1 and lower than the moving speed.

In this embodiment, as the wiping roller 21, a roller in which a velvet (for example, Corduroy 70000/731, manufactured by Omi Velvet Co., Ltd.) in which a raised cloth is formed in a ridge shape is attached to the circumferential surface. ing.
The angle of the ridge is set to about 45 degrees. As a material of the velvet, for example, cotton can be used, but synthetic fibers such as polyester and nylon are more advantageous in terms of durability.

Waste ink adheres (transfers) to the wiping roller 21 that has wiped the written ink image.
However, the waste ink adhering to the wiping roller 21 is scraped off by the dressing roller 22, whereby the wiping roller 21 is refreshed (recovered) to a state before wiping. The rotation direction of the dressing roller 22 is set in a direction opposite to the rotation direction of the wiping roller 21, and
The rotation speed (peripheral speed) of the dressing roller 22 is set to about twice the rotation speed (peripheral speed) of the wiping roller 21. In the case of a spiral brush roller, the rotation speed of the dressing roller 22 needs to correspond to the spiral pitch. The reason is that it is necessary to remove one round of waste ink during one rotation of the wiping roller 21.

FIG. 10 is a schematic sectional view of a channel structure of a spiral brush forming the dressing roller, and FIG. 11 is a schematic longitudinal sectional view of a dressing roller (roller of a spiral brush) 22 in which the winding of the brush is reduced. 12 is a front view of the dressing roller of FIG. 11, FIG. 13 is a schematic longitudinal sectional view of a dressing roller (roller of a spiral brush) 22 in which a brush is densely wound, and FIG. It is a front view of the dressing roller of FIG. As shown in FIGS. 10 to 14, a brush 25 having the channel structure is spirally wound around a roller shaft 24 to form a roller brush. As shown in FIGS. The density of the spiral brush can be adjusted by the winding method.

As shown in FIGS. 11 and 12, when the winding method is sparse, the amount of waste ink taken in and the contact pressure can be reduced. However, it is difficult to wipe the entire surface unless the rotation speed (peripheral speed) is increased. is there. On the other hand, as shown in FIG. 13 and FIG.
Can be dressed (refreshed),
The contact pressure increases, the driving load increases, and the waste ink tends to be easily taken in the brush 25, and the collection efficiency tends to decrease. Therefore, in practicing the present invention, a dressing roller 22 in which the winding of the brush 25 is reduced as shown in FIGS. 11 and 12 is used.
By using such a loosely wound dressing roller 22, the wiping roller 21 can be used without taking in waste ink.
The waste ink adhering to the was collected in the waste ink recovery tray 23. Further, waste ink dropped from between the belt-shaped recording medium 1 and the wiping roller 21 or between the wiping roller 21 and the dressing roller 22 is collected in a waste ink collecting tray 23 below, and is collected when the ink is replaced. System.

In the above embodiment, the present invention has been described by exemplifying a case where an image is formed by the ink jet recording means 3. However, the present invention is directed to a solid jet recording means for recording using a solid ink and an ink jet recording method. Belt-shaped recording medium 1 such as a thermal transfer recording means for recording by melting and heating a ribbon;
As long as an image can be formed on a recording medium, it can be similarly applied to writing by using various types of recording means other than the ink jet recording means, and the same effect can be obtained. In the above embodiment, the carriage 9 on which the recording means (recording head) 3 is mounted is mounted on the recording medium 1.
Although the serial writing engine 10 that performs writing while relatively moving the writing engine 10 has been described as an example,
The present invention provides various types of electronic devices regardless of the type of writing method, such as a line-type writing engine that performs writing only by sub-scanning using line-type recording means having a length that covers the entire width or a part of the recording medium 1. It is applicable to a blackboard and can achieve the same effect.

Also, the present invention provides an electronic blackboard for writing using one recording means (recording head), a color image electronic blackboard for writing with a plurality of recording means for recording in different colors, and different colors of the same color. An electronic blackboard using a writing engine of a recording method, such as an electronic blackboard for a gradation image in which writing is performed by a plurality of recording means for recording density, or an electronic blackboard in which the color image and the gradation image are combined. For example, irrespective of the number of recording means (recording heads) or the arrangement of ejection ports in the case of ink jet recording means, the present invention can be similarly applied to various electronic blackboards and can achieve the same effect. It is.

Further, in the case of the writing engine of the ink jet recording system, the present invention uses a replaceable ink jet cartridge in which the ink jet head and the ink storing section (ink cartridge etc.) are integrated, and separates the ink jet head and the ink storing section. It is possible to apply the arrangement configuration of the ink jet head and the ink storage unit in any case, such as a configuration in which the ink supply tube and the like are connected between them, and the same effect can be obtained. . Note that the present invention can be applied to a case where an ink jet writing engine performs recording using, for example, an electromechanical transducer such as a piezo element. This provides an excellent effect in an electronic blackboard using an engine. According to such a method, it is possible to achieve higher density and higher definition of recording.

[0035]

As is apparent from the above description, according to the present invention (claim 1), a writing engine for writing an image on a belt-shaped recording medium by a recording means and an image for erasing an image written on the belt-shaped recording medium are provided. An erasing engine, wherein the erasing engine includes a wiping roller for wiping an image written on the belt-shaped recording medium, and a dressing roller for scraping off ink attached to the wiping roller. Because it was configured to have
By making the image fixing property and the image peeling property of the belt-shaped recording medium compatible, it is possible to repeatedly write and erase the image on the belt-shaped recording medium, and to refresh the writing surface of the belt-shaped recording medium. Provided is a recording-type electronic blackboard that can be written at any time and can easily collect waste ink that has been wiped off for image erasure.

According to the second to ninth aspects of the present invention, in addition to the configuration of the first aspect, the recording means is an ink jet recording means for writing an image by discharging ink, A wiping roller, and a configuration in which the wiping roller and the dressing roller are in rolling contact with each other in the opposite direction; the wiping roller is formed of a columnar member to which a wiping cloth is attached; and the dressing roller is formed of a brush. A brush, a brush, a velvet, or a non-woven fabric; a brush, a spiral brush; and a dressing roller, the surface of the brush being made of a chemical such as polyester or nylon. The recording means is capable of writing a full-color image. Since the configuration is an inkjet recording unit, or the inkjet recording unit is configured to include an electrothermal converter that generates thermal energy used for ejecting ink, it is possible to achieve the above effects more efficiently. Can be.

[Brief description of the drawings]

FIG. 1 is a side sectional view showing a schematic structure of a first embodiment of an electronic blackboard to which the present invention is applied.

FIG. 2 is a front view of the display surface viewed from an arrow 2-2 in FIG. 1;

FIG. 3 is a cross-sectional view of the back surface as viewed from an arrow line 3-3 in FIG. 1;

FIG. 4 is a plan sectional view showing a schematic structure of a second embodiment of the electronic blackboard to which the present invention is applied.

FIG. 5 is a front view of the display surface viewed from an arrow line 5-5 in FIG. 4;

FIG. 6 is a side sectional view taken along line 6-6 in FIG. 5;

FIG. 7 is a partial perspective view schematically illustrating a structure of an ink discharge unit of the recording unit in FIG.

FIG. 8 is a schematic diagram showing an arrangement of a writing engine and an erasing engine of an electronic blackboard to which the present invention is applied, together with a belt-shaped recording medium.

FIG. 9 is a schematic sectional view showing the configuration of an embodiment of an electronic blackboard erasing engine to which the present invention is applied.

FIG. 10 is a schematic sectional view of a channel structure of a spiral brush forming a dressing roller in FIG. 9;

FIG. 11 is a schematic longitudinal sectional view of the dressing roller in FIG. 9 with a brush wound in a sparse manner.

FIG. 12 is a front view of the dressing roller of FIG. 11;

FIG. 13 is a schematic longitudinal sectional view of the dressing roller in FIG. 9 with a brush wound densely.

FIG. 14 is a front view of the dressing roller of FIG.

[Description of Signs] 1 Belt-shaped recording medium (display screen) 2 Recording medium sub-scanning means (conveyance driving means) 3 Recording means (inkjet recording means, image forming means) 4 Recording head main scanning means 5 Ink storage means (ink cartridge) , Ink tank) 6 ink supply means 7 erasing engine 8 waste ink collecting means 9 carriage 10 writing engine 11 guide rail 12 roller 13 roller 21 wiping roller 22 dressing roller 23 waste ink collecting tray 24 roller shaft 25 brush 81 discharge port surface 82 discharge Outlet 83 Common liquid chamber 84 Liquid path 85 Electrothermal converter

Claims (9)

[Claims] 1. An electronic blackboard comprising: a writing engine for writing an image on a belt-shaped recording medium by a recording unit; and an erasing engine for erasing an image written on the belt-shaped recording medium, wherein the erasing engine includes the belt-shaped recording medium. An electronic blackboard comprising: a wiping roller for wiping an image written on a recording medium; and a dressing roller for scraping off ink attached to the wiping roller. 2. The electronic blackboard according to claim 1, wherein said recording means is an ink jet recording means for writing an image by discharging ink. 3. The belt-shaped recording medium and the wiping roller, and the wiping roller and the dressing roller,
The electronic blackboard according to claim 1, wherein the electronic blackboard makes rolling contact in opposite directions. 4. The wiping roller according to claim 1, wherein the wiping roller is formed of a cylindrical member to which a wiping cloth is adhered, and the dressing roller is formed of a cylindrical member formed of a brush. Electronic blackboard described in crab. 5. The electronic blackboard according to claim 4, wherein the wiping cloth is a woven fabric, a raised cloth, a velvet, or a nonwoven fabric. 6. The electronic blackboard according to claim 4, wherein the brush is a spiral brush. 7. The electronic device according to claim 4, wherein the dressing roller is a columnar member in which a cloth in which chemical fibers such as polyester or nylon are electrostatically planted is attached to a surface of the brush. blackboard. 8. The electronic blackboard according to claim 1, wherein said recording means is an ink jet recording means capable of writing a full-color image. 9. The ink jet recording device according to claim 2, further comprising an electrothermal converter for generating thermal energy used for discharging ink.
Electronic blackboard according to any of the above.