JP2002264304A - Inkjet printer - Google Patents

Abstract

(57) [Problem] To provide an ink jet printer capable of outputting, at high speed, recording paper on which a print image surface has been overcoated. An overcoat processing unit (30) is provided downstream of a printing unit (20), and print processing and overcoat processing are performed in parallel at different positions on recording paper (P). Of the recording paper P after the overcoat processing by the cutter unit 40 provided on the downstream side of
To cut.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an ink jet printer.

[0002]

2. Description of the Related Art Ink jet printers are widely used as color image printing means. By the way, the print image of the ink jet printer has low storability depending on the material of the ink, and if left as it is, the ink is oxidized by ozone in the air, and the print image fades in a few days.

Conventionally, as a process for improving the storability of a printed image of an ink jet printer, an overcoat process for forming an overcoat layer (a transparent thin film layer) on the surface of the printed image has been performed. By performing the overcoating process on the print image, the ink of the print image is shielded from ozone in the air, so that oxidation of the ink can be prevented, and discoloration of the print image can be prevented.

[0004]

However, conventional ink jet printers are generally equipped only with a function of printing an image, and an apparatus for performing an overcoat process separately from the ink jet printer is prepared. Therefore, it is necessary to separately perform overcoat processing after printing an image with an ink jet printer and cutting with a cutter, and the overcoat processing of a printed image has a problem that it is complicated and troublesome. .

SUMMARY OF THE INVENTION In view of the above, it is an object of the present invention to provide an ink jet printer capable of outputting a recording sheet having a printed image surface overcoated at a high speed.

[0006]

According to the first aspect of the present invention,
In an ink jet printer including a printing unit that prints an image by discharging ink onto a recording paper, and a conveyance system having a driving unit that conveys the recording paper to the printing unit, the printing unit includes a printing unit downstream of the printing unit in the conveyance direction. An overcoat processing unit that forms an overcoat layer on the recording paper, and a cutter unit that cuts the recording paper in accordance with an image size is provided downstream of the overcoat processing unit in the transport direction. It is an inkjet printer characterized by the following.

According to this configuration, the overcoat processing section is provided downstream of the printing section, the printing processing and the overcoat processing are performed in this order, and the rear end of the recording paper is provided downstream of the overcoat section. When the recording paper is conveyed to the position of the cutter unit, the recording paper is cut as it is, so that the recording paper on which the overcoat processing has been performed is output at high speed.

[0008]

FIG. 1 is a block diagram showing one embodiment of an ink jet printer according to the present invention. The ink jet printer shown in FIG.
0, a printing unit 20 provided in the middle of the transport system 10, an overcoat unit 30 provided downstream thereof, and a cutter unit 40 on the downstream side, and a control unit 50 for controlling the driving of these units. equipped with a.

The transport system 10 includes a feed roller 11 on which the recording paper P wound in a roll shape is loaded, and sequentially feeds the recording paper P from the feed roller 11 toward the downstream side. for rewinding dimension of the pair of conveying rollers rotating in opposite directions 12, the recording sheet P
Is composed of a transport table 13 having a required length to be transported on the upper surface, and a pair of unloading rollers 14 rotating in opposite directions for unloading the recording paper P from the transport system 10. Transport roller pair 1
Reference numeral 2 denotes a driving roller 121 which is rotated at a constant peripheral speed by a motor 12M, and a driven roller 122 which is urged in a direction in which the driving roller 121 is pressed against the driving roller 121. Transfer has been realized.

The printing unit 20 includes a print head 21 that is disposed close to and opposed to the upper surface of the transfer table 13. The print head 21 is long in a direction perpendicular to the transport direction, and has at least the width of the recording paper P. Known print heads 21 are employed, and although not shown, nozzles for discharging ink at a predetermined pitch in the longitudinal direction are arranged and formed. An ejection mechanism that uses, for example, a piezoelectric element or the like for performing an operation is configured inside. The number of nozzle lines is not limited to one, but may be a structure having a predetermined number of lines. In order to print a color image, the print head 21 has, for example, a nozzle array structure of three rows for each color in the transport direction, and uses cyan, magenta, and yellow inks, respectively. I have. A mode in which the print heads of each color are individually adopted may be adopted.

Image data desired to be printed is sequentially output to the printing unit 20 for one line (or for the predetermined number of lines) as a nozzle driving voltage signal from an unillustrated image data storage unit. and the ejection drive control of the ink by. During this printing period, a two-dimensional image of a required size is printed on the surface of the recording paper P by the constant speed transfer of the recording paper P by the transport system 10.

The transfer table 1 facing the print head 21
3, a plurality of small holes are formed, and a motor drive fan 131 for generating a negative pressure is provided in a chamber formed on the back surface side of the table. By adsorbing on the upper surface of the transfer table 13, floating is prevented, and the distance from the nozzle is kept constant.

The overcoat section 30 is located at the downstream end of the transport table 13 and in the present embodiment, the print head 21 has a length longer than a predetermined length of a printable image size.
It is arranged at a position close to the. Overcoat section 3
Numeral 0 denotes a ribbon cassette 31 for accommodating the ribbon R coated with the overcoat material so as to be able to be fed out, a thermal head 32 whose dimension in the direction perpendicular to the transport direction corresponds to the width dimension of the recording paper P, and a platen opposed to the thermal head 32. A roller 33 is provided. The ribbon R is provided between the thermal head 32 and the platen roller 33, and the take-up roller 311 is driven to rotate at a peripheral speed equal to the transfer speed of the recording paper P by a motor (not shown) or the like. The thermal head 32 has a heating member housed therein, generates heat by supplying electric power, and thermally transfers the overcoat material of the ribbon R to the recording paper P to perform an overcoat process.

The structure of the thermal head 32 of the overcoat section 30 and an example of a drive circuit will be described with reference to FIG.

The thermal head 32 has a predetermined number of, for example, 256 thermistors TH1 to TH256 as heating elements arranged at equal intervals at a width corresponding to the printing width of the printing unit 20.

The shift register 321 has 256 bits and converts data into parallel data. The clock input CLK and the serial data input DAT receive 256-bit driving data which is a high-level heat generation driving signal from the clock input CLK and the serial data input DAT. , Thermistors TH1 to TH2 from each bit
At the same time, the data is output for a predetermined period of time (at least for the image size). NA1 to NA256 are N as gates for directly driving the thermistors TH1 to TH256.
It is an AND circuit. The enable input G turns on / off the driving of the thermal head 32, and the thermistor is heated at a high level. The driving data a1 to a256 output from the shift register 321 are synchronized with the high level timing of the enable input G and the thermistor T
Output to H1 to TH256.

The control unit 50 stores the size of the recording paper P (A4
For each size, B5 size, postcard size, etc.), driving data in which the high level is arranged in the thermistor in the area where the recording paper P passes in the thermal head 32 and the low level is arranged in the thermistor outside the passing area for 256 bits is stored in advance. The control unit 50 controls the driving data according to the size of the recording paper P to be used, preferably the recording paper size detected by the size detecting means, or the size data when the print size is determined from the image data. Is transferred to the shift register 321, the enable input G is switched to the high level, the thermal head 32 is driven, and the overcoat process is performed.

As described above, the driving data is input to the shift register 321 in accordance with the size of the recording paper P used for printing, and the heat generation area of the thermal head 32 is switched in the width direction. The thermal transfer of the overcoat material by an amount corresponding to the width of the recording paper P prevents the overcoat material from adhering to the platen roller 33 even when the size of the recording paper P is switched.

The cutter unit 40 is disposed downstream of the overcoat unit 30 and, after the overcoat processing, the transport system 10
When the recording paper P is conveyed by the printer and the rear end of the print image is conveyed to the position of the lower blade 141 of the cutter unit 40,
The upper blade 142 is rotated in the direction of the arrow, the upper blade 1
The recording paper P is cut while being sandwiched between the lower blade 42 and the lower blade 141. Cut printed image, while being unloaded by the discharging roller pair 14, the leading edge of the recording sheet P is rewound to the standby position (the state of FIG. 1) by the conveying roller pair 12.

When the control unit 50 receives the print start instruction,
Output of image data to the printing unit 20 and ink ejection processing, constant-speed transfer driving processing preset as a suitable speed for printing the recording paper P, operation start and drive end of the overcoat unit 30, and cutter unit This is to drive the recording paper P, carry out the cut recording paper P, and reversely feed the remaining recording paper P to the standby position.

The position of the recording paper P is controlled by a pair of conveying rollers 12.
This can be achieved by detecting a drive pulse signal to the motor 12M that rotates. Alternatively, a system in which a proximity sensor such as a photo interrupter or a mechanical switch is disposed at each of the standby position, the printing position, the overcoat position, and the cut position to directly detect the position may be adopted.

The control system 50 collectively controls each unit, and includes a transport amount of the recording paper P from the standby position, a printing position on the transport path, an overcoat position, a cut position, and a recording paper P.
Based on data such as paper size and print image size of
By performing calculations and controls, control of the transport system 10 and parallel processing in the printing unit 20 and the overcoating unit 30 are performed.

Next, the printing of the recording paper P and the overcoat process will be described.

When a print start instruction is received, the recording paper P is conveyed to the printing unit 20 and printing is started. Ink is ejected from the print head 21 of the printing unit 20 to print an image on the recording paper P in line units. When the image is printed and the image size is large, the recording paper P during printing is sequentially conveyed to the overcoat unit 30. In the overcoat section 30, the thermal head 3
2, the overcoat material on the surface of the ribbon R is thermally transferred onto the surface of the recording paper P to perform an overcoating process.

The cutter section 40 sequentially cuts the recording paper P each time the rear end of each print image is conveyed after the overcoat processing. The discharge unit 14 discharges the cut recording paper P (print image).

[0026] As described above, the overcoat portion 30 provided on the downstream side of the printing unit 20 performs printing processing and overcoating parallel at different locations on the recording paper P, on the downstream side of the overcoat portion 30 By cutting the recording paper P after the overcoat processing by the provided cutter unit 40, for example, a temporary reverse feed is not necessary for an apparatus having a processing procedure of performing the overcoat after the cut, The overcoated recording paper can be output at higher speed.

In an apparatus using sheet paper as the recording paper P, by providing a sheet paper feeding mechanism in place of the feed roller 11, printing and overcoating are similarly performed in the printing unit 20 and the overcoating unit 30. Processing can be performed.

[0028]

According to the first aspect of the present invention, an overcoat processing section is provided on the downstream side of the printing section, the printing processing and the overcoat processing are performed in this order, and the rear end of the recording paper is overcoated. When the recording paper is conveyed to the position of the cutter unit provided downstream of the processing unit, the recording paper is cut as it is, so that the recording paper on which the overcoat processing has been performed is output at high speed.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of an ink jet printer of the present invention.

FIG. 2 is a circuit diagram of the thermal head 32.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Conveying system 20 Printing part 30 Overcoat part 31 Ribbon cassette 32 Thermal head 33 Platen roller 40 Cutter part 50 Control part

Claims (1)

[Claims] 1. An ink jet printer comprising: a printing unit that prints an image by discharging ink onto a recording paper; and a transport system that has a driving unit that transports the recording paper to the printing unit. An overcoat processing section for forming an overcoat layer on the recording paper on the downstream side in the direction, and a cutter section for cutting the recording paper in accordance with the image size on the downstream side in the transport direction of the overcoat processing section. An ink jet printer, characterized in that: