JPH09295401A - Ink jet recording device - Google Patents

Abstract

(57) [Summary] (Correction) [Problem] To take curling habits according to their degree. SOLUTION: A reverse warp unit 15 is displaced on a lower side of a recording head in a paper transport direction by a displacement adjusting cam 23.
The recording paper S is provided from the platen 3 to the discharge roller 28.
By pressing the second serrated roller 19 at the tip of the paper pressing lever 17 and changing the amount of reverse warp thereof, different curl habits are obtained depending on the type of paper and the printing duty.

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, and more particularly, to an ink jet recording apparatus provided with a curling mechanism.

[0002]

2. Description of the Related Art An ink jet recording apparatus in which a recording medium is heated by a heated platen roller before and after recording and writing to quickly adsorb and dry the ink to improve the image quality, The applicant has already applied for Japanese Patent Application No. 7-91683.

This type of ink jet recording apparatus not only enables image formation without ink bleeding or rubbing, but when a resin component is added to the ink, the fixing effect further enhances the quality of printed matter such as water resistance. It has the advantage that it can.

On the other hand, on the other hand, since this type of ink jet recording apparatus performs recording and writing with liquid ink in a state in which the recording paper is wound around a heated platen roller, a curl occurs on the recording paper. There is provided a means for curling the recording paper in a direction opposite to the curl by a peeling claw that makes contact with the surface of the platen roller at an angle.

However, even if such a means can be applied to the peculiar curl generated in the apparatus, such as the diameter and temperature of the platen roller or the wrapping angle of the recording paper on the platen roller. However, it has a disadvantage that it is not possible to deal with curl quirks caused by a difference in printing duty such as the thickness of the recording paper used, the type of paper, or whether the contents to be recorded are characters or photographs.

[0006]

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and its object is to:
Another object of the present invention is to provide a new ink jet recording apparatus which can easily cope with a difference in curling habit based on parameters such as the type of paper used and print duty, and take the curling habit.

[0007]

That is, the present invention provides an ink jet recording apparatus for achieving the above object, which is drawn out by a paper discharge roller on the peripheral surface of a platen roller located on the lower side of the recording head in the recording medium conveying direction. A warp means that acts on the recording medium to warp the recording medium in a direction opposite to the direction of the curl in accordance with the degree of the curl of the recording medium generated during recording and writing is provided so that the warp amount can be adjusted. It is something that is done.

[0008]

Embodiments Now, the embodiments shown in the drawings will be described. The drawings show an embodiment of the present invention applied to an inkjet printer configured to form a color image using various color inks containing a resin component.

First, a schematic configuration of this printer is shown in FIG.
It is explained based on. This printer is configured to perform recording and writing while sequentially recording the recording sheets S stacked on the paper feed tray 2 along the peripheral surface of the platen roller 3 and send the recording paper S to the discharge tray 9 in a U-shape. There is.

The platen roller 3 in this embodiment is
The roller driving motor (not shown) is configured to rotate in the clockwise direction in the figure, and the platen roller 3 is provided with a halogen lamp 4 as a heat source at its axis, and the radiant heat of the halogen lamp 4 causes the recording head to rotate. The recording paper S is heated at the portions on the upper side and the lower side in the rotation direction with the sheet 7 sandwiched therebetween.

A gate roller 6 is provided on the platen roller 3 on the upper side of the recording head 7, and the recording paper S sent out by the paper feed roller 5 is arranged at a timing. And a paper pressing operation unit 10, which will be described later, and a reverse warping unit 15 on the lower side of the recording head 7.
The peeling claw 25 and the peeling claw 25 are sequentially arranged in the paper conveying direction, and the recording paper S for which the recording and writing processing has been completed is pulled out from the recording and writing section, and the curl generated therein is removed and discharged to the discharge tray 9. Is configured to.

The above-mentioned paper pressing operation unit 10 presses the leading end of the recording paper S fed to the recording / writing unit and allows it to pass through the recording / writing unit at the same speed as the platen roller 3. As shown in FIGS. 3 (a) to 3 (d), the paper pressing operation unit 10 has a substantially triangular shape which is rotated clockwise around the fulcrum 14 from the standby position to the pressing release position. Of the swing arm 11 and a thin holding plate 12 swingably attached to the tip of the swing arm 11 via a support member, and the swing arm 11 is rotated toward the recording head 7. Initially, while the paper pressing roller 8 arranged immediately after the recording head 7 is separated from the platen roller 3, the leading end 12a of the held paper pressing plate 12 is floated from the platen roller 3 to enter the recording writing section. , Ide, while pressing the leading edge of the recording sheet S that has been incorporated sent here, the recording sheet is sent to the rear of the recording head 7 along a circumferential surface thereof with the platen roller 3,
Finally, the pressing of the leading end of the recording paper is released to take over the recording paper S to the next reverse warp unit 15.

On the other hand, the reverse warp unit 15 arranged on the lower side of the paper pressing operation unit 10 has the peeling claw 25.
It acts on the recording paper S separated from the platen roller 3 by the action of the platen roller 3 to give it a warp in the opposite direction to the curved surface of the platen roller 3 to take up its curl. The amount of displacement is adjustable by 23, and by pressing the recording paper S from above between the platen roller 3 and the paper discharge roller 28, the degree of curl caused by the difference in paper type and print duty The amount of reverse warp according to is added to the recording paper S.

That is, as shown in FIGS. 4 (a) to 4 (c), the reverse warp unit 15 has a paper pressing lever 17 pivotally supported by a fulcrum 16 on the upper side in the paper conveying direction as a fulcrum. And a first serrated roller 18 that presses the recording paper S against the platen roller 3 at a portion o that is axially supported by the intermediate portion of the paper pressing lever 17 and intersects a tangent line on the platen roller 3 that extends to the paper discharge roller 28. By a second serrated roller 19 which is axially supported by the end of the paper pressing lever 17 on the lower side in the paper transport direction and presses between the platen roller 3 and the paper discharge roller 28 so as to give the recording paper S a reverse warp. Further, the paper pressing lever 17 is provided with a cam 23 for adjusting a displacement amount, which is driven via a reduction gear train 22 by a drive motor 22 (FIG. 2) that operates according to a signal according to the type of paper and the printing duty. By It is configured to swings to a point 16 around.

Reference numeral 22 in the drawing denotes a drive motor 22.
The reduction gear train 25 interposed between (FIG. 2) and the displacement adjustment cam 23 is always attached to the spring 26 immediately after the reverse warp unit 15 to separate the recording paper S from the surface of the platen roller 3. Each of the peeling claws has its tip slidably contacting the peripheral surface of the platen roller 3 in a biased state, and reference numeral 20 in the drawing indicates rotation in a direction of separating the paper pressing lever 17 from the recording paper S. It shows the spring being energized.

Next, a paper feeding operation and an operation of taking a curl by the apparatus thus configured will be described. In order to record and write on plain paper, first specify "plain paper" on the operation panel 30, and set the reverse warp unit 15 to the position shown in FIG.
After being displaced to the position of (a), a print operation button (not shown) is operated.

As a result, when the paper feed roller 5 which has started to operate in response to a print command signal from a control circuit (not shown) sends the recording paper S from the paper feed tray 2 to the peripheral surface of the platen roller 3, the recording paper S is halogenated. The peripheral surface of the platen roller 3 heated by the lamp 4 is heated in contact with the peripheral surface of the platen roller 3, and is sent to the recording head 7 in a state where moisture is removed.

Then, the leading edge of the recording paper S is shown in FIG.
As shown in (a), when the underside of the paper pressing plate 12 standing by with a gap between it and the platen roller 3 is sunk,
The paper pressing unit 10 is synchronized with this, and the swing arm 11
Is rotationally displaced toward the recording head 7 side, and the front end of the recording paper S is pressed against the peripheral surface of the platen roller 3 by the front end of the paper pressing plate 12 supported at the front end thereof.

Then, the paper pressing unit 10 nips the front end of the recording paper S without hindering the running of the recording head 7 and transfers it to the lower side of the recording head 7 at the same speed as the platen roller 3. During this period, the recording / writing process is performed, and finally when the platen roller 3 is separated from the peripheral surface ((d) of the same figure), the reverse warp unit 15 located on the lower side thereof.
Next, the recording paper S is fed by the first serrated roller 18.
Is pressed on the platen roller 3.

By the way, when "plain paper" is designated by operating the operation panel 30 prior to the start of printing, the displacement adjusting cam 23 driven by the cam driving motor 21 is rotated as shown in FIG. ), The paper pressing lever 17 is displaced so as to position the second serrated roller 19 below the tangent line connecting the contact o on the platen roller 3 and the paper discharge roller pair 28.

Therefore, the recording paper S which has undergone the recording and writing process and the heating and drying process and has a curl along the curved surface of the platen roller 3 is peeled off from the platen roller 3 by the peeling claw 25 and is discharged to the paper discharge roller 28. When the recording paper S is discharged to the bottom of the sheet, the recording paper S is pushed by the second serrated roller 19 from the top under the condition that the recording paper S is pulled by the paper discharge roller 28 whose peripheral speed is slightly higher than the peripheral speed of the platen roller 3. Since the pressure is applied, the curl is loosely received and the curl is taken by this reverse warp processing, and the curl is discharged onto the discharge tray 9.

On the other hand, when recording and writing on a thick paper S such as a postcard which is greatly curled by heating by the platen roller 3, "thick paper" is designated on the operation panel 30 in advance.

As a result, as shown in FIG. 4 (b), the cam 23 causes the paper pressing lever 17 to be further rotated and displaced in the clockwise direction in the drawing, thereby causing the platen roller 3 and the paper discharge roller 2 to move.
The second serrated roller 19 is strongly contacted with the thick paper S discharged while being applied with a tensile force between the second and the second stirrer 8, and the second serrated roller 19 is largely bent in the opposite direction so as to be proportional to the amount of the curl, and the curl is taken. .

On the other hand, when performing recording / writing on a thin recording medium made of a material having heat resistance and resilience such as polyethylene terephthalate used for the overhead protector, based on a signal designated on the operation panel 30. The cam drive motor 21 is reversed, and as shown in FIG. 4C, the paper pressing lever 17 is displaced in the non-pressing direction via the cam 23 for adjusting the displacement amount.

As a result, the tension of the abolished roller 28 acting on the recording medium S causes the second serrated roller 19 on the paper pressing lever 17 to retreat on the tangent line of the platen roller 3, so that a curling habit may occur due to its own elasticity. Pressing on this type of recording medium that recovers without interruption is avoided.

In the above description, the amount of reverse warp of the recording paper S is set according to the type of paper. However, when a solid image such as a photograph is written while heating the recording paper, or the character It is also possible to set the amount of reverse warp so as to correspond to the degree of curl caused by the size of the printing duty, such as when writing a line image like. It is also possible to set the amount of reverse warp or set the amount of reverse warp corresponding to a combination thereof.

In the above-described embodiment, the present invention has been described by way of an example of an ink jet recording apparatus of the type in which recording and writing are performed on the recording paper S while heating, but a general non-heat type ink jet The present invention can also be applied to a recording apparatus, and in the above-described embodiment, the displacement of the reverse warp unit 15 is adjusted by designating the type of paper and the print duty. Reverse warping unit 15 depending on the paper type detected by
Can also be configured to automatically adjust the displacement.

[0028]

As described above, according to the present invention, the displacement of the reverse warp means that acts on the recording medium that hits the paper discharge roller and gives the warp in the opposite direction in order to take up the curl generated in the recording medium is adjusted. Since it is possible, the curl can be completely taken according to the thickness of the recording medium, the elasticity thereof, or the degree of curl caused by parameters such as a line image or a solid image to be recorded. Moreover, by arranging the cam so that the displacement of the reverse warp means is adjusted, the reverse warp means can be freely adjusted according to the degree of curl with a simple structure.

[Brief description of drawings]

FIG. 1 is a side view of an apparatus according to an embodiment of the present invention applied to a heating type inkjet recording apparatus.

FIG. 2 is a perspective view showing a main part of the device.

3A to 3D are diagrams showing a paper pressing operation.

FIG. 4A to FIG. 4C are diagrams showing reverse warp operations for each paper type or print duty.

[Explanation of symbols]

 3 Platen Roller 7 Recording Head 10 Paper Pressing Operation Unit 15 Reverse Warp Unit 16 Paper Pressing Lever 18 First Grating Roller 19 Second Grating Roller 23 Displacement Adjusting Cam 25 Peeling Claw 28 Discharging Roller Pair

Claims (5)

[Claims] 1. A degree of curling of the recording medium that occurs at the time of recording and writing on a peripheral surface of a platen roller located on the lower side in the recording medium conveying direction of the recording head, acting on the recording medium pulled out by a paper discharge roller. Accordingly, the ink jet recording apparatus is characterized in that the warp amount is provided so that the warp amount of the recording medium can be adjusted in a direction opposite to the curl direction. 2. The ink jet recording apparatus according to claim 1, wherein the reverse warp means is provided on a peripheral surface of a platen roller provided with a recording medium heating means. 3. A first roller that presses a recording medium at a portion where a tangential line on the platen roller that intersects with the paper discharge roller intersects a lever that can adjust the amount of warp as the reverse warp means, and the first roller. 2. The ink jet recording apparatus according to claim 1, further comprising a second roller that is pressed on the lower side of the roller so as to give a reverse warp to the recording medium. 4. The ink jet recording apparatus according to claim 1, wherein the amount of displacement of the reverse warp means is adjustable by a cam member that operates according to a signal corresponding to the type of recording medium. 5. The ink jet recording apparatus according to claim 1, wherein the amount of displacement of the reverse warp means is adjustable by a cam member that operates according to a signal designated according to the print duty.