JP2941119B2 - Ink jet recording device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet recording apparatus for performing recording by discharging ink from an ink discharge port toward a recording member, and more particularly to a fixing mechanism for fixing ink on recording paper.

[0002]

2. Description of the Related Art When ink immediately after recording by an ink jet recording apparatus touches a recording paper which is not dried, an image may be disturbed or ink may adhere to a hand. In an ink jet recording apparatus having a high recording speed, the second recording paper may overlap before the ink on the first recording paper dries, and the back surface of the first recording paper may become dirty. For this reason,
Among the ink jet recording apparatuses, particularly, a high-speed recording model requires means for drying the ink and fixing the ink on recording paper.

Conventionally, as a means for drying and fixing ink, a heat fixing method for mainly applying heat has been widely used. Among the heat fixing methods, a method in which a heat source such as a heater is directly brought into contact with the back surface of a recording surface of a recording paper and heat is transferred to the ink through the recording paper to heat and fix the ink is most often used. I have.

Further, a method of irradiating the recording paper with light such as far infrared rays to elevate the temperature of the recording paper to evaporate and fix the ink is often used.

Further, a method is also used in which hot air is applied to the recording surface side of the recording paper to dry and fix the ink.
In this case, there is a risk that the ink droplets are blown off (before fixing) by the wind pressure and the image is destroyed.

[0006]

Among the above-mentioned prior arts, the method in which a heat source such as a heater is brought into direct contact with the back surface of the recording surface of the recording paper is based on the method in which the back surface of the recording surface of the recording paper is heated. If they are not uniformly adhered to each other, there is a problem that it is difficult to obtain a fixing effect and it is difficult to realize the effect. Further, there is a problem that the image is distorted when the recording surface is directly pressed against the heat source by a flat surface. When a configuration is adopted in which the recording surface is pressed at a number of points, there are two points: In addition, there is a problem that the density of the ink becomes uneven, and the recording paper also has ripples.

In the case of the method of irradiating light,
There is a problem that the efficiency of heat conversion is low. Furthermore, it is effective for evaporating the ink near the surface of the recording paper,
There is a problem that it is difficult to evaporate the ink that has penetrated into the recording paper.

In the method in which hot air is applied to the recording surface of the recording paper to dry and fix the ink, there is a risk that the ink droplets are blown off (before fixing) by the wind pressure and the image is destroyed. There is a problem.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned prior art, and ink is dried and fixed without unevenness without causing disturbance of an image on a recording paper or waving on the recording paper itself. It is an object of the present invention to realize an ink jet recording apparatus capable of performing the above.

[0010]

An ink jet recording apparatus according to the present invention is an ink jet recording apparatus which performs recording by discharging ink droplets from a recording head onto a recording material. The fixing of the ink is performed by blowing hot air on the back surface of the recording material opposite to the recording surface.

In this case, a fan for blowing air to the back surface opposite to the recording surface of the recording material on which an image is formed by the attachment of the ink droplets, and the fan sends air to the back surface of the recording material. A heater for heating the air to be blown, and a duct for covering the fan and the heater and for sending hot air from the open surface to the back surface of the recording surface of the recording material, wherein the air intake of the duct is provided. May be provided at a position for sucking the back surface of the recording surface of the recording material immediately after recording by the recording head, and
The surface other than the open surface may be closed so that the wind sent to the back surface of the recording material circulates.

[0012]

According to the present invention, a fan (hot air) is applied to the back side of the recording surface of the recording material by a fan, so that ink droplets are not blown off and uniform heat is applied to the recording paper without disturbing the image. This makes it possible to efficiently dry the permeated ink, and to prevent unevenness and ripples of the recording material that occur during fixing.

[0013]

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

FIG. 1 is a sectional view showing a main part of the first embodiment of the present invention.

This embodiment is based on a method in which hot air is applied to the back side of the recording surface of the recording paper to dry and fix the ink.
The recording head 111 performs recording on the recording paper 107 as a recording material. Around the platen roller 108, a platen pressing roller 109 for holding the recording paper 107 together with the platen roller 108, and the recording paper 10 during recording.
Paper press plates 110 for pressing the sheet 7 against the platen roller 108 are sequentially provided in the direction in which the recording paper 107 is conveyed.

The recording paper 107 after the recording by the recording head 111 is carried on a transport roller 10 comprising a plurality of rollers.
5 and is discharged out of the apparatus by a pair of discharge rollers 106. Since the transport roller 105 transports the recording paper 107 in contact with the recording surface, a water repelling process for preventing the ink from adhering to the surface so that the ink does not adhere and disturb the recorded image is performed. It has been subjected. A plurality of rod-shaped heaters 10 as heat sources are provided below the transport roller 105.
2, and a fan 101 is provided at a lower portion thereof. These fan 101 and rod heater 1
02 is housed in the duct 112,
The air taken in from outside is turned into hot air when passing through the rod-shaped heater 102, is blown on the back surface of the recording surface of the recording paper 107, and is then discharged out of the duct 112.

In this embodiment, since hot air is blown on the back side of the recording surface of the recording material, the ink droplets discharged on the recording surface are blown off, and uniform heat is applied to the recording paper without disturbing the image. As a result, the permeated ink was efficiently dried, thereby preventing unevenness and ripples of the recording material occurring during fixing.

FIG. 2 is a sectional view showing a main part of a second embodiment of the present invention, and FIG. 3 is a perspective view thereof.

In the first embodiment shown in FIG. 1, there is a danger that the recording paper is agitated by the air discharged out of the duct and the image is disturbed. In the present embodiment, this is to prevent this, and the shape of the duct 203 accommodating the fan 101 and the rod-shaped heater 102 is the same as that of the duct 11 shown in FIG.
2 is formed differently. Another configuration is shown in FIG.
Are the same as those in the first embodiment shown in FIG. 1, and the same reference numerals as those in FIG.

The duct 203 is provided with a suction portion 204 formed in a mesh shape (see FIG. 3) as an air intake. The suction unit 204 constitutes a holding unit, and is provided between the recording head 111 and the conveyance roller 105 so as to contact the back surface of the recording surface of the recording paper 107. Air is taken in through. As described above, by being sucked by the suction unit 204, the positional relationship between the recording paper 107 and the recording head 111 is fixed, and good recording is performed.

Next, the recording operation of this embodiment will be described.

When a recording operation command is issued from a device control unit (not shown) which receives a command from an external device (not shown) such as a computer, a recording paper 107 is fed, and a platen pressing roller 109 and a platen roller The sheet is conveyed by being sandwiched between the sheets. When the recording paper 107 is transported to a position several millimeters from the leading end of the paper holding plate 110, recording is performed by the recording head 111. When the recording paper 107 after recording is sent to the suction unit 204, the recording paper 107 is sucked by the suction unit 204 by the rotation of the fan 101, and is conveyed while closely contacting. The suction unit 204 is configured such that the fan 101
07 is a portion for taking in air from outside of the apparatus in order to send air for drying and fixing, and in order to prevent the recorded paper 107 from contacting the recording head 111 and disturbing the image, It also plays the role of forcibly biasing and transporting in the direction. For this reason, in order to avoid that the recording paper 107 is completely sealed when the recording paper 107 passes through, the air intake section 204 is formed wider than the width of the recording paper 107, and is configured to allow air to enter from a gap.

Subsequently, the recording paper 107 is conveyed to the ink fixing mechanism. The ink fixing mechanism includes a fan 101, a rod-shaped heater 102, and a transport roller 105 provided in a duct 103.
This is a portion for drying the ink on the recording paper 107 recorded by 1 and performing fixing by heat. A rod-shaped heater 102 is used as a heat source. The air indicated by the white arrow taken in by the intake section 204 is generated by the rod-shaped heater 10.
The recording paper 107 is heated by the heat generated by the fan 2 and becomes hot air indicated by a black arrow. The hot air has a high temperature (about 160 °), and the conveying speed of the conveying roller 105 is controlled such that the hot air hits the recording paper 107 evenly for 4 seconds.

After passing through the ink fixing mechanism, the recording paper 107 is discharged by a discharge roller pair 106.

The ink ejection amount of the apparatus used in this embodiment was 27 nl / mm2.

As described above, as the fixing means of the ink jet recording apparatus, the ink is dried and fixed by heating the back side of the recording surface of the recording paper with hot air, thereby efficiently fixing the ink. Is also effective. Further, since heat is evenly transmitted, there is no adverse effect such as uneven fixing or waving caused by the fixing unit. In addition, since it is not necessary to rotate the fan except when recording is performed, noise during standby can be reduced.

Further, the recording paper after the recording is sucked by a simple structure in which the air suction port of the ink drying fan is disposed at a portion where the recording paper 107 passes immediately after the recording, and the recording paper advances upward and the head is moved to the head. Prevents rubbing. Thereby, a good image is always obtained, and the reliability of the apparatus can be remarkably improved without increasing the cost.

FIG. 4 is a sectional view showing the structure of a main part of a third embodiment of the present invention.

In this embodiment, the transport roller 405 constituting the ink fixing mechanism is movable up and down, and a guide for guiding the recording paper 107 to a paper passing path between the transport roller 405 and the discharge roller pair 106 is provided. 401 is provided.
Other configurations are the same as those of the second embodiment shown in FIG. 2, and therefore, the same reference numerals as those in FIG.

The operation of this embodiment will be described. At the start of recording on the recording paper 107, the transport roller 405 is lowered to the same position as the transport roller 105 shown in FIG.
When the recording paper 107 recorded by the recording head 111 is sent by the platen roller 108 and the platen pressing roller 109, the recording paper 107 is conveyed so that the leading end thereof is sandwiched and the ink is fixed by the ink fixing mechanism. Thereafter, when the recording paper 107 is guided by the paper ejection roller pair 106 through the guide 401 and the conveyance by the paper ejection roller pair 106 is started, the conveyance roller 405 moves upward and separates from the recording paper 107. . With such a configuration, the chance of contact between the recording surface of the recording paper 107 and the transport roller 405 and the possibility of disturbing the image are reduced, and excellent image recording can be performed.

FIG. 5 is a sectional view showing the structure of a main part of a fourth embodiment of the present invention.

In this embodiment, the duct 203 for accommodating the fan 101 and the rod-shaped heater 102 shown in FIG. 2 is replaced by a circulation type circulation duct 503 for accommodating the dehumidifying filter 504 and the absorber 513. It is. Other configurations are the same as those of the second embodiment shown in FIG.
The same reference numerals as in FIG. 2 are assigned and the description is omitted.

The ink fixing mechanism in this embodiment includes the above-mentioned circulation duct 503 and the transport roller 105 provided above the circulation duct 503. The upper end surface of the circulation duct 503 on the side of the recording head 111 is disposed so as to sandwich the recording paper 107 together with the transport roller 105 and serves as a holding unit. Thereby, the recording paper 107
The positional relationship between the print head 111 and the print head 111 is fixed, and good printing is performed.

In the circulation duct 503, air circulates in the order of the fan 101, the bar-shaped heater 102, and the gradual humidity filter 504. The fan 101 and the bar-shaped heater 102 are shown in FIG.
And the same arrangement as shown in FIG.

In this embodiment, the hot air blown to the recording paper 107 is circulated, but the hot air blown to the recording paper 107 contains a large amount of water in the evaporated ink. The gradual humidity filter 504 is provided with a cooling mechanism (water cooling by a Peltier element or a water pipe) provided for recovering water contained in the hot air, and collects water vapor in the hot air as water droplets. It is absorbed and collected by an absorber 513 provided at the lower part. Slow humidity filter 504
The air cooled by the heater is again heated by the rod-shaped heater 102 and blown onto the recording paper 107.

The material constituting the circulation duct 503 used in the present embodiment has a high heat insulating effect. As a result, the amount of heat radiated to the outside was reduced, and the amount of heat loss was reduced.

In this embodiment, since the hot air blown to the recording paper for drying the ink is circulated and used, an ink fixing mechanism having high thermal efficiency can be obtained. Further, since hot air does not flow out of the circulation duct 503, it is not necessary to devise an outlet, for example, it is not necessary to use a component having a high heat-resistant temperature or to provide a cooling mechanism for cooling and exhausting the hot air. Could be simplified.

In this embodiment, the gradual humidity filter 5 is used.
Although the description has been made assuming that the absorber 513 is provided at the lower part of the 04, in order to simplify the configuration, instead of the absorber 513, a window for checking the storage state of water and a water draining means such as a plug and a tube are provided. Is also good. Further, a diffusion and emission unit such as a fan and an ultrasonic mechanism for discharging the water accumulated in the absorber 513 to the outside of the apparatus during standby for printing may be provided.

In each of the embodiments described above, the conveying roller 105 subjected to water repellent processing is used as the conveying means of the recording paper 107 constituting the ink fixing mechanism. However, as shown in FIG. The recording paper 107 may be conveyed by driving the spur train 601 passing through a very small spur.

In each of the embodiments, an ink jet recording apparatus is used. However, the present invention can be widely applied to an ink fixing mechanism of a recording apparatus which performs fixing by heat, such as electrophotography in which powder such as toner is placed on a recording sheet to form an image.

The typical constitution and principle of the ink jet recording head and recording apparatus according to the present invention are described in, for example, US Pat. Nos. 4,723,129 and 4,7,129.
It is preferred to use the basic principles disclosed in US Pat. No. 40,796. 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, the electric heat disposed corresponding to the sheet or liquid path holding the liquid (ink) is used. By applying at least one drive signal to the converter, which provides a rapid temperature rise exceeding nucleate boiling in accordance with the recorded information, heat energy is generated in the electrothermal converter, and consequently this drive signal This is effective because air bubbles in the liquid (ink) can be formed correspondingly. By discharging the liquid (ink) through the discharge opening by the growth and contraction of the bubble, at least one droplet is formed. When the drive signal is formed into a pulse shape, the growth and shrinkage of the bubble are performed immediately and appropriately, so that the ejection of a liquid (ink) having particularly excellent responsiveness can be achieved, which is more preferable. As the pulse-shaped drive signal, those described in U.S. Pat. Nos. 4,463,359 and 4,345,262 are suitable. It should be noted that U.S. Pat. No. 4,313,124 of the invention relating to the rate of temperature rise of the heat acting surface.
If the conditions described in the specification are adopted, more excellent recording can be performed.

As the configuration of the recording head, in addition to the combination of a discharge port, a liquid path, and an electrothermal converter (a linear liquid flow path or a right-angled liquid flow path) as disclosed in the above-mentioned respective specifications, The present invention also includes a configuration using U.S. Pat. No. 4,558,333 and U.S. Pat. No. 4,459,600 which disclose a configuration in which a heat acting portion is arranged in a bending region. It is. In addition, Japanese Unexamined Patent Application Publication No. 123670/1984 discloses a configuration in which a common slit is used as a discharge portion of an electrothermal transducer for a plurality of electrothermal transducers, and an opening for absorbing a pressure wave of thermal energy is provided. The present invention is also effective as a configuration based on JP-A-59-138461 which discloses a configuration corresponding to a discharge unit.

Further, as a full line type recording head having a length corresponding to the width of the maximum recording medium that can be recorded by the recording apparatus, a combination of a plurality of recording heads as disclosed in the above-mentioned specification is used. Either a configuration that satisfies the length or a configuration as a single recording head that is integrally formed may be used, but the present invention can more effectively exert the above-described effects. In addition, a replaceable chip-type recording head that can be electrically connected to the device main body and supplied with ink from the device main body when attached to the device main body, or the ink tank is integrated with the recording head itself The present invention is also effective when a cartridge-type recording head provided in a fixed manner is used.

It is preferable to add recovery means for the printhead, preliminary auxiliary means, and the like provided as components of the printing apparatus of the present invention since the effects of the present invention can be further stabilized. If you list these specifically,
A capping unit, a cleaning unit, a pressurizing or suctioning unit, a preheating unit using an electrothermal transducer or a heating element other than these, or a combination thereof, and a preliminary ejection for performing a different ejection from recording to the recording head. Performing the mode is also effective for performing stable recording.

Further, the printing mode of the printing apparatus is not limited to the printing mode of only the mainstream color such as black, and may be a single printing head or a combination of a plurality of printing heads. The present invention is also very effective for an apparatus provided with at least one of full colors by color mixture.

[0046]

Since the present invention is configured as described above, it has the following effects.

According to the first aspect of the present invention, since hot air is applied to the back surface of the recording surface of the recording material, the ink droplets ejected on the recording surface are blown off, and the recording paper is evenly distributed without disturbing the image. Heat can be applied, the permeated ink can be dried efficiently, and there is an effect that unevenness occurring at the time of fixing and ripples of the recording material can be prevented.

According to the second aspect of the present invention, since the positional relationship between the recording head and the recording material during recording is constant and hot air is blown on the back surface of the recording surface, each of the above effects can be further improved. There is an effect that can be.

According to the third aspect, in addition to the above effects, there is an effect that a fixing mechanism having good thermal efficiency can be provided.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a configuration of a main part of a first embodiment of the present invention.

FIG. 2 is a sectional view showing a configuration of a main part of a second embodiment of the present invention.

FIG. 3 is a perspective view of the embodiment shown in FIG. 2;

FIG. 4 is a sectional view showing a configuration of a main part of a third embodiment of the present invention.

FIG. 5 is a sectional view showing a configuration of a main part of a fourth embodiment of the present invention.

FIG. 6 is a perspective view showing a configuration of a spur train 601 used in place of the transport roller 105 in FIGS. 1 to 5;

[Explanation of symbols]

 101 Fan 102 Bar Heater 103, 203 Duct 105, 405 Conveying Roller 106 Discharge Roller Pair 107 Recording Paper 108 Platen Roller 109 Platen Pressing Roller 110 Paper Pressing Plate 111 Recording Head 204 Suction Port 401 Guide 503 Circulation Duct 504 Slow Moisture Filter 513 Absorption Body 601 spur train

Continuation of front page (56) References JP-A-5-42670 (JP, A) JP-A-55-87564 (JP, A) JP-A-56-130383 (JP, A) (58) Fields studied (Int .Cl. ⁶ , DB name) B41J 2/01

Claims (3)

(57) [Claims] An ink jet recording apparatus that performs recording by ejecting ink droplets from a recording head to a recording material, wherein the recording surface of the recording material on which an image is formed by the attachment of ink droplets An ink jet recording apparatus, wherein the ink is fixed by blowing hot air on the opposite back side. 2. An ink jet recording apparatus which performs recording by discharging ink droplets from a recording head onto a recording material, wherein the recording surface of the recording material on which an image is formed by the attachment of ink droplets is A fan for blowing air to the opposite back surface side, a heater for heating the wind sent to the back surface of the recording material by the fan, and a recording of the recording material from the open surface, covering the fan and the heater. A duct for sending hot air to the back side of the surface, wherein the air intake of the duct is provided at a position for sucking the back side of the recording surface of the recording material immediately after recording by the recording head. An ink jet recording apparatus. 3. An ink jet recording apparatus which performs recording by discharging ink droplets from a recording head onto a recording material, wherein the recording surface of the recording material on which an image is formed by the attachment of ink droplets is A fan for blowing air to the opposite back surface side, a heater for heating the wind sent to the back surface of the recording material by the fan, and a recording of the recording material from the open surface, covering the fan and the heater. A duct for sending hot air to the back of the surface, wherein the duct is closed except for the open surface so that the wind sent to the back of the recording material circulates. Inkjet recording device.