JP2000296607A - Inkjet printer - Google Patents

Abstract

PROBLEM TO BE SOLVED: To enhance the drawing quality of an ink jet printer. SOLUTION: The paper held between a feed roller 22 and a pressure roller 28 is fed onto a platen 8 by the rotation of the feed roller 22 to be heated to desired temp. set to a temp. range of 35-50 deg.C by the heater 7 provided to the platen 8. Ink drops heated to the same temp. as the heated paper 40 by a heater 39 are emitted to the heated paper 40 from an ink jet recording head 38 to form an image on the paper 40.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention generally relates to a computer hard copy printer, and more particularly, to an ink jet printer in which ink droplets are ejected from an ink jet type recording head onto a sheet on a platen to form an image on the sheet. Regarding printers.

[0002]

2. Description of the Related Art Conventionally, a heater is attached to a platen,
Japanese Patent Application Laid-Open No. 4-263949 or Japanese Patent No. 2576470 discloses an ink jet printer in which a sheet on a platen is heated by heating a platen, and an ink droplet ejected from a recording head is attached to the sheet to form an image. Etc.

[0003]

In drawing by an ink-jet printer, fine drawing or poor image quality may sometimes be obtained due to slight differences in the material of the drawing medium (paper, film, etc.). In particular, the effect is large when drawing is performed with solvent-based ink. In the case of solvent-based ink, since the ink enters the drawing medium while slightly dissolving the drawing medium,
Depending on the material of the drawing medium, the ink may easily bleed, which is considered to have an effect.

[0004] This has a large effect when a solvent-based ink is used, but such an effect is also recognized when another type of ink is used. There is a problem that the diameter and shape of the ink dots are not uniform depending on how the ink bleeds, and the finished accuracy of the finished product (drawing, picture, etc.) is poor, and the finished product is not beautiful. When the ink is ejected to the recording head and reaches the drawing medium, if there is a difference between the temperature of the ink and the temperature of the drawing medium, a rapid change in the temperature of the ink occurs, and disturbance such as diffusion and bleeding occurs.

As a result, it has been found that the shape of the ink dots does not become a uniform circular shape or the diameter of the ink dots does not become uniform, and as a result, the finishing accuracy deteriorates. SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problems, and has as its gist that both the drawing medium and the ink (recording head) are heated so that they are substantially at the same temperature.

[0006]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention is directed to an ink jet type recording apparatus which heats a paper support provided on an airframe and heats the paper on the paper support. In an ink jet printer that ejects ink droplets from a head and draws an image on the paper,
The recording head is heated and the temperature of the ink ejected from the recording head is made substantially the same as the temperature of the heated paper. In the present invention, the temperature of the heating paper is set to an arbitrary value between 35 ° C. and 50 ° C.

[0007]

Embodiments of the present invention will be described below in detail with reference to the accompanying drawings. In FIG. 2, 2
Is a body of the ink jet printer, which is supported by the legs 4. A stand 6 extending in the direction perpendicular to the paper is fixed to the body 2, and a platen 8 having a heater 7 is supported on the stand 6 via the stands 10, 10. 14 are provided.

Reference numeral 16 denotes a pair of columns (the other columns are not shown) fixed near both ends of the gantry 6, and a Y-rail 18 is erected above them. The gantry 6 includes a support table 20.
Is fixed, and a feed roller 22 is supported by the support base 20. The feed roller 22 is connected to an X-axis driving device controlled by a controller (not shown).
A plurality of roller holders 24 are rotatably supported on a shaft 26 on the Y rail 18. A pressure roller 28 is rotatably supported at the tip of each of the roller holders 24 so as to face the feed roller 22.

The rear end of the roller holder 24 is supported by the tension force of a tension spring 30 with the shaft 26 as a fulcrum.
Medium, biased clockwise. The roller holder 24
A cam shaft 32 on which a cam 32a is fixed is rotatably supported on an upper surface of the cam shaft 32, and a lever 34 is fixed to one end of the cam shaft 32. When the lever 34 swings manually or the like, the cam shaft 32 rotates, and the pressure of the cam 32a causes the roller holder 24 to swing around the shaft 26 in the counterclockwise direction in FIG. Are separated from each other by a predetermined distance.

When the lever 34 is returned to the original position, each pressure roller 28 elastically contacts the feed roller 22 by the tensile elastic force of each spring 30. A Y cursor 36 is movably attached to the Y rail 18 via rollers. The Y cursor 36 has an ink jet type recording head 38.
The recording head 38 is opposed to the platen 8.

The recording head 38 has a built-in heater 39. Temperature sensors 46 and 48 are attached to the platen 8 and the recording head 38.
The configuration is such that temperature signals of the platen 8 and the recording head 38 are supplied from 48 to the controller of the ink jet printer. The heaters 7 and 39 are connected to the controller via driving units 50 and 52, respectively.

The platen 7 and the paper guides 12 and 14
Constitutes a paper support, and the heater 7 can be disposed at a printing portion of the paper support and at a suitable position upstream of the printing portion. The roll paper 40 fed from the roll portion 40 a of the roll paper supported by the leg 4 passes through the guide roller 42, the paper guide 12, the space between the feed roller 22 and the pressure roller 28, the platen 8 and the paper guide 14, and 4
It is configured to be taken up by a take-up roller 44 supported by the roller.

When the roll paper 40 is set on the platen 8, the pressure roller 28 is raised from the feed roller 22, the roll paper 40 is inserted between the rollers 22, 28, and then the pressure roller 28 is lowered to apply the pressure. Pressure roller 28 and feed roller 2
2 sandwiches the roll paper 40.

When the power supply of the ink jet printer is turned on, the heaters 7 and 39 are energized, whereby the platen 8 and the recording head 38 are heated. Based on the temperature control program software 56 stored in the ROM 54 of the controller, the temperatures of the platen 8 and the recording head 38 can be changed from 35 ° C. to 50 ° C. based on the roll paper 40 on the platen 8 and the ink ejected from the nozzles of the recording head 38. The controllers are controlled to be substantially the same between C.

As a result of experiments, it has been confirmed that the drawing quality does not improve at a temperature of 35 ° C. or lower and the effect is extremely small. In order to raise the temperature of the drawing medium, the method of raising the temperature of the platen 8 on which the drawing medium is mounted is the simplest and most easily adopted method. However, when this method is adopted, the temperature is increased. Since the drawing medium having a lower temperature moves on the platen 8, the temperature of the platen 8 needs to be higher than the desired temperature of the drawing medium.

However, since the platen 8 is generally located at a position where an operator's hand or the like touches, it is dangerous to raise the temperature unnecessarily, and the limit is about 55 ° C. Assuming that the upper limit of the temperature of the platen 8 is 55 ° C., the temperature of the drawing medium moving thereon is about 50 ° C. in consideration of the above-mentioned temperature drop, and this is the upper limit. When the type of ink and the type of drawing medium are constant, the recording head 3
The set temperatures of the platen 8 and the platen 8 are fixed, and temperature setting data is recorded in the temperature control program software 56 in advance.

When the type of ink and the type of drawing medium are not constant, the set temperatures of the recording head 38 and the platen 8 are variable, and the set temperature can be input from the operation panel 58 by a key. In this case, the set temperature is read from the host computer 60 to the RAM of the controller.
62 is input. When the inkjet printer shifts to the drawing operation, the feed roller 22 is intermittently rotated clockwise in FIG. 1 by the X drive unit 62, and the roll paper 40 moves rightward on the platen 8.

On the other hand, the Y cursor 36 is reciprocated by the Y drive section 64 along the Y rail 18 in the direction perpendicular to the plane of FIG. Further, the vector data transmitted from the host computer 60 is transferred to the RAM 62 via an interface (I / F) 64 having a FIFO buffering function.
It is taken in.

The CPU 66 of the ink jet printer includes:
Based on the program stored in the ROM 54, the RAM
The vector data stored in the block 62 is subjected to pre-processing such as division processing and sorting in a preset band width and block width (data analysis), and the vector data included in each block of each band is intermediately processed. The format of the code (for example,
Vector data). The image processor 68 uses R
The image data in the intermediate code format stored in the AM 62 is sequentially subjected to DDA processing, and raster data is developed in the bitmap memory 70.

The raster data developed in the bitmap memory 70 is converted from RGB color data to CMYK data. Next, the CPU 66 sequentially sends the raster data converted into CMYK data to the recording head 38 via the head driving unit 70. The recording head 38 is supplied with ink by an ink supply driving unit 72, and the recording head 38 discharges ink droplets under the control of the head driving unit 70 to form an image on the roll paper 40.

[0021]

According to the present invention, as described above, the drawing quality can be improved.

[Brief description of the drawings]

FIG. 1 is an explanatory side sectional view of an ink jet printer.

FIG. 2 is a block diagram illustrating functions of the inkjet printer.

[Explanation of symbols]

 2 Body 4 Leg 6 Frame 7 Heater 8 Platen 10 Unit 12 Paper Guide 14 Paper Guide 16 Support 18 Y Rail 20 Support 22 Feed Roller 24 Roller Holder 26 Shaft 28 Pressure Roller 30 Spring 32 Camshaft 34 Lever 36 Y Cursor 38 Recording head 39 Heater 40 Roll paper 42 Guide roller 44 Take-up roller 46 Temperature sensor 48 Temperature sensor 50 Platen heater drive 52 Head heater drive 54 ROM 56 Temperature control program software 58 Operation panel 60 Host computer 62 X drive 64 Y drive Unit 66 CPU 68 image processor 70 head drive unit 72 ink supply drive unit

Claims (2)

[Claims] An ink jet recording head discharges ink droplets onto a heated paper while heating a paper support provided on the body and heating the paper on the paper support so that printing is performed on the paper. Wherein the temperature of the ink ejected from the recording head is substantially the same as the temperature of the heated paper. 2. The method according to claim 1, wherein the temperature of the heating paper is set to an arbitrary value between 35 ° C. and 50 ° C.
An inkjet printer according to item 1.