JPH06305126A - Ink jet printing apparatus - Google Patents

Abstract

PURPOSE:To perform printing good in the fixing of ink and color development without generating wrinkles in paper at a time of printing even under a high humidity condition. CONSTITUTION:A paper feed cassette 13 having papers stacked therein and a paper feed roller 15 are covered with a cover 14 and hot air generated in a power supply part is introduced into the cover 14 through a duct 47 to gradually heat the papers 11 and each of the papers 11 is dehumidified before it reaches a platen 35.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet type printing apparatus for fixing ink by heating.

[0002]

2. Description of the Related Art Conventionally, an ink jet printer using hot melt ink has a paper feed section, a printing section, and a paper ejection section. As shown in FIG. 3, the sheet feeding unit includes a sheet feeding cassette 53 that stores stacked sheets 51, and stacked sheets 51.
The uppermost sheet is fed by a sheet feeding roller 55, and a sheet feeding motor (not shown) that rotates the sheet feeding roller 55 via a gear train (not shown).

As shown in FIG. 3, the printing section is equipped with a jet head 71 for jetting hot melt ink that has been heated and melted, and a carriage 73 that moves in parallel with the paper surface and perpendicular to the paper feed direction, and a carriage. A pair of guide bars 72 for guiding and supporting 73, a carriage motor 74 for moving the carriage 73, a platen 75 for supporting the paper 51 from the back side of the printing surface at the time of printing, and a platen 75 attached to the platen 75 to move the paper 51 through the platen 75. Heater 76 to heat
And located downstream of the paper feed roller 55 in the paper feed direction,
It is configured by a pair of paper feed rollers 61 that feed the paper 51 onto the platen 75.

The sheet discharge section is composed of a pair of sheet feed rollers 69 for feeding the sheet 51 from the platen 75, and a sheet discharge tray (not shown) for stocking the fed sheet 51.

The above-mentioned paper feed rollers 61 and 69 are driven by a motor 65 via a belt 63.
Further, the above-mentioned components are supported by a frame (not shown).

A series of operations of the inkjet printer having the above configuration will be described. The sheets 51 stacked on the sheet feeding cassette 53 are guided one by one from the sheet feeding cassette 53 to the sheet feeding roller 61 by the rotation of the sheet feeding roller 55. Further, the paper 51 is fed onto the platen 75 by the paper feed roller 61 and heated by the heat of the heater 76. Here, the ink ejection head 71 mounted on the carriage 73 ejects the molten ink onto the paper 51 to perform printing. The paper 51 for which printing has been completed is sent out from the platen 75 by the paper feed roller 69, and is discharged onto the paper discharge tray provided downstream.

The paper 11 must be heated on the platen 75 because the surface temperature of the paper 51 is room temperature or
When the amount is less than that, as soon as the melted ink droplets ejected from the ink ejecting head 71 reach the surface of the paper 51, the heat amount of the melted ink drops is taken by the paper 51 and is rapidly cooled. Therefore, the ink droplets solidify into a spherical shape on the surface of the paper 51 and the paper 5
This is because not only the ink is not sufficiently fixed to No. 1 but also the area where the ink covers the surface of the paper 51, that is, the so-called hiding rate becomes low and the color development is not good. The above-mentioned platen 75 was heated to about 65 ° C. by the heater 36.

[0008]

However, when the printing apparatus is used in a high humidity condition of 20 ° C. and 80%, the sheets 51 stacked on the sheet feeding cassette 53 absorb moisture. Then, when the absorbed paper 51 is sent out onto the platen 75, the contact surface of the paper 51 with the platen 75 is rapidly raised from 20 ° C. to 65 ° C., and the moisture contained in the paper 51 is dehumidified at once. The contact surface tries to shrink. On the other hand, the temperature of the surface which is not in contact with the platen 75 does not rise so rapidly, so that the moisture contained in the paper 51 is gradually dehumidified, and the non-contact surface does not shrink so much. That is, the difference in shrinkage amount between the front surface and the back surface of the paper 51 causes wrinkles on the paper 51.

Due to the wrinkles, the conventional ink jet printer causes heating unevenness on the surface of the paper 51 to disturb the print image, or the paper 51 floats above the platen 75, and the paper 51 is loaded on the carriage 73. Contact with the ejection head 71 caused paper jams. In the worst case, the ink ejection head 71 may be destroyed by the contact with the paper 51.

The present invention has been made in order to solve the above-mentioned problems, and can heat a paper without causing wrinkles on the paper to achieve printing with good ink fixing and good color development. To provide a printing device.

[0011]

In order to achieve this object, a printing apparatus of the present invention comprises a head for ejecting heat-meltable ink onto a sheet on a platen, and the ejected ink is fixed on the sheet by heat. A heater for heating the platen in order to perform the heating, a paper feeding unit for feeding the paper, and a heating unit for heating the paper in advance before printing.

The heating means comprises a power supply cooling fan for discharging heat generated by the power supply device and a duct for introducing hot air discharged from the power supply cooling fan to the paper feeding unit. Is composed of a paper feed cassette for accommodating a plurality of stacked paper sheets, a paper feed means for conveying the papers in the paper feed cassette one by one, and a cover for covering the entire paper feed cassette. The hot air introduced from the duct may be retained in the cassette.

[0013]

In the printing apparatus of the present invention having the above construction, the temperature is raised by the heating means and the moisture contained in the paper is gradually dehumidified by the temperature rise before printing.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment embodying the present invention will now be described with reference to FIGS.
This will be described with reference to FIG.

The printing apparatus using the hot melt ink of the present invention has a sheet feeding section A, a printing section B and a power source section 4 as shown in FIG.
3, the sheet feeding section A has a sheet discharging section C, and the sheet feeding section A stores sheet 11 stacked as shown in FIG. 2, a sheet feeding cassette 13, a sheet feeding roller 15, a sheet feeding cassette 13, and a sheet feeding roller 15.
The cover 14 is provided with a duct 47 for independently covering the other parts, a feed motor (not shown) that is attached to the cover 14 and rotates the feed roller 15, and a gear train.

As shown in FIG. 2, the printing section B is equipped with a jet head 31 for jetting hot melt ink which has been heated and melted, and a carriage 33 and a carriage 33 which move in parallel to the paper surface and perpendicular to the paper feeding direction. A pair of guide bars 32 that guide and support, a carriage motor 34 that moves the carriage 33, a platen 35 that supports the paper 11 from the back side of the printing surface during printing, and a heater that is attached to the platen 35 and that heats the paper 11 via the platen 35. 36, located downstream of the paper feed roller 15 in the paper feed direction, and provided with a platen 3
A pair of paper feed rollers 21 for feeding the paper 11 onto the sheet 5.
It is composed by.

As shown in FIG. 2, the paper discharge section C is composed of a pair of paper feed rollers 29 for feeding the paper 11 from the platen 35 and a paper discharge tray (not shown) for stocking the fed paper 11. The paper feed rollers 21 and 29 are driven by a paper feed motor 25 via a belt 23.

Paper feed motor 17, carriage motor 3
4. As shown in FIG. 1, the power sources for driving the paper transport motor 25 and heating the heater 36 are collectively arranged in one place to form a power source section 43. A fan 45 that cools the power supply unit 43 is attached near the power supply unit 43, and an air discharge unit of the fan 45 and the cover 14 that covers the entire paper feed cassette 13 are connected by a duct 47. The above-mentioned components are supported by a frame (not shown). The fan 45 and the duct 47 correspond to the heating means of the present invention.

A series of operations of the printing apparatus having the above configuration will be described. Sheets 11 stacked on the sheet cassette 13
Is rotated one by one from the uppermost paper by the rotation of the paper feed roller 15, and from the paper feed cassette 13 to the paper feed roller 21.
Will be guided to. Further, the paper 11 is the paper feed roller 21.
Is sent onto the platen 35 and heated by the heat of the heater 36. Here, the ink ejection head 31 mounted on the carriage 33 ejects the molten ink onto the paper 11 to perform printing. The paper 11 on which printing is completed is sent out from the platen 35 by the paper feed roller 29, and is discharged onto the paper discharge tray along the guide member.

A paper feed motor, a carriage motor 34, a paper feed motor 25, and a heater 36 which perform the above series of operations.
The power supply unit 43, which constitutes the power supply of the above, generates heat to drive them, and raises the ambient atmospheric temperature. The air whose ambient temperature has risen is discharged by the fan 45, and passes through the duct 47 to feed the paper cassette 13 and the paper feed roller 15.
Is introduced into the cover 14 for covering the cover 14 and raises the ambient temperature in the cover 14. That is, the sheets 11 stacked in the sheet feeding cassette 13 are gradually heated, and the sheet 1
The heat is conducted to the entire sheet 1 and the water contained in the sheet 11 is gradually dehumidified. Therefore, when heating at this time, the paper 11
Wrinkles do not occur. Then, the sheet is fed to the printing section B by the sheet feeding roller 15 and the sheet feeding roller 21, and the platen 3
5 has been sufficiently dehumidified at the time when it is sent to the sheet 5, and the sheet 1
There is no difference in the shrinkage amount between the front surface and the back surface of No. 1. Therefore, wrinkles do not occur, and inconveniences such as paper jams during printing are eliminated.

Further, since the printing apparatus of this embodiment uses the power source unit 43 as a heat source, it does not require a special heat source and can efficiently perform heating in terms of power consumption.

The ink jet type printing apparatus of the present invention is not limited to the above embodiment, and can be modified within the scope of the invention.

For example, in the above-mentioned embodiment, in order to raise the ambient temperature in the cover 14, the air whose ambient temperature in the power source 43 has risen is sent into the cover 14 through the duct 47. However, a heater is mounted in the cover 14. Similar effects can be obtained by directly heating.

Further, the paper feed cassette 13 and the paper feed roller 1
The cover 14 is set to cover the sheet 5, but this is for efficiently heating the sheet 11 of the sheet feeding section A. If the heating amount by the power source section 43 has a sufficient margin, the cover 14 is intentionally set. Need not be set.

Further, if the outlet of the duct 47 from the power source section 43 is connected to the section of the sheet guide 8 for guiding the sheet 11 from the sheet feeding section A to the printing section B shown in FIG. Since it is always one sheet at a time, more efficient paper 11
Can be heated.

[0026]

As is apparent from the above description, the printing apparatus using the hot melt ink of the present invention gradually heats the paper before printing even in a humid environment.
Since it is dehumidified, wrinkles do not occur on the paper even during heating during printing, and printing can be performed without disturbing the print image or causing paper jams.

Further, by incorporating a heat source from the power supply device, a special heat source is not required, and a simple structure enables efficient heating in terms of power consumption.

[Brief description of drawings]

FIG. 1 is a structural diagram illustrating a structure of a printing apparatus according to an exemplary embodiment of the present invention.

FIG. 2 is a detailed view of each part that constitutes the printing apparatus according to the embodiment of the present invention.

FIG. 3 is a detailed view of each part that constitutes the conventional printing apparatus.

[Explanation of symbols]

 11 Paper 13 Paper Feed Cassette 14 Cover 15 Paper Feed Roller 31 Jet Head 35 Platen 36 Heater 43 Power Supply 45 Fan 47 Duct

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI technical display location B41J 29/00 9113-2C B41J 29/00 G

Claims (2)

[Claims] 1. A head for ejecting heat-meltable ink onto a sheet on a platen, a heater for heating the platen to fix the ejected ink on the sheet by heat, and a sheet feeding section for feeding the sheet. An inkjet printing apparatus comprising: a heating unit that heats the paper in advance before printing. 2. The heating unit includes a power supply cooling fan that discharges heat generated in a power supply device, and a duct that introduces hot air discharged from the power supply cooling fan to the paper feeding unit. Is composed of a paper feed cassette that stores a plurality of stacked paper sheets, a paper feed unit that conveys the paper sheets in the paper feed cassette one by one, and a cover that covers the entire paper feed cassette. The inkjet type printing apparatus according to claim 1, wherein hot air introduced from a duct is held in the cassette.