JPH08207262A - Ink jet printer - Google Patents

Abstract

PURPOSE: To dry a part of recording paper, which is wetted by printing, efficiently by a heater in accordance with a printing density. CONSTITUTION: A distance between the printing place of a recording head 2 to the side of the row of plane heaters 20A and the like is equal to the common laterial dimensions of respective plane heaters while the total sum of the side size of respective plane heaters is equal to the total recording width of a recording paper 8. Wetness, printed on a recording paper area 8A and the like, shown by one-dot chain lines connected to the upper part of the place of printing from the lateral side of upper side of respective plane heaters, are dried during passing through the upper part of the plane heater 20A and the like, opposed to the wetness and shown by a broken line. Further, the amount of heat for drying is ideal to determine it in accordance with the actual number of dots printed on respective recording paper areas 8A and the like by a time until respective recording paper areas are superposed on the plane heaters corresponding to them from the shown position in a diagram. The control of amount of heat for the drying or the control of an electric power supplied to the plane heater is effected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printer for printing with an ink jet recording head that reciprocates over the entire recording width while feeding out a recording paper, and the portion of the recording paper that has been printed and is wet according to its printing density. The present invention relates to an inkjet printer capable of efficiently drying a heater.

[0002]

2. Description of the Related Art Conventionally, an ink jet recording method has advantages that it is recorded in a non-contact manner, noise is extremely small, and high speed recording is possible. If not dried quickly,
In the process of feeding the recording paper, there is a drawback that it is rubbed against a feed roll or the like to contaminate the portion and the print recording portion is soiled to deteriorate the print quality.

In order to eliminate this drawback, as a method of drying the printed recording paper portion as soon as possible, an ink having a low surface tension, that is, an ink which is easy to dry is used, a recording paper which absorbs ink quickly is used, and the entire recording width is used. It has been put to practical use to install one corresponding heater.

[0004]

The conventional methods (1) to (3) have the following problems. In the method using the ink having a low surface tension, so-called satellites, in which small dots are scattered around the main dot in the central portion, are likely to occur. In the method of using the recording paper of which the ink absorption is fast, the print dots are likely to bleed, and the print quality is degraded. Since the heater installation method always heats the heater,
The heater is also used to dry the recording paper portion, which has a small print portion and is not necessarily required, which increases the electric power cost and the running cost of the printer.

The problem to be solved by the present invention is to solve the above-mentioned problems of the prior art and to efficiently dry the wet printed and printed recording paper portion with a heater in accordance with the printing density. To provide a printer.

[0006]

SUMMARY OF THE INVENTION The present invention relates to a printer for printing with an ink jet recording head that moves over the entire recording width while feeding the recording paper,
A rectangular surface heater having a horizontal dimension obtained by dividing the entire recording width of the recording paper into one or more and a common vertical dimension is arranged in a row in the horizontal direction, and the side close to the printing position The common horizontal side of is positioned at the same distance as the vertical dimension of the surface heater from the printing position in the feeding direction, and
An array of surface heaters arranged in parallel and close to the surface of the recording paper; the same rectangular recording paper area that is connected to each surface heater begins to overlap with the surface heater as the recording paper is fed out, and only until the time of complete overlap , To generate heat according to the number of dots printed on each recording paper area,
And a power control unit that supplies power to the corresponding surface heaters.

Further, when the number of dots printed on each recording paper area is equal to or less than the set value, it is preferable that the power supplied to the corresponding surface heater is zero.

[0008]

According to the present invention, the surface heater array is positioned at a position separated from the printing position in the feeding direction by the same distance as the vertical dimension of the surface heater, and the common horizontal side near the printing position is positioned.
It is arranged in parallel and close to the surface of the recording paper. Electric power is supplied to the heaters on each surface by the electric power control unit, and a heat amount corresponding to the number of dots printed on each recording paper area is generated. The duration of the amount of heat generated is the time from when the corresponding recording paper area begins to overlap with the surface heater until it completely overlaps due to the feeding. As a result, each recording paper area is dried with a heating strength according to the number of printing dots printed on the recording paper area, that is, the degree of wetting. Similarly, the next recording paper area is dried at a heating strength corresponding to the actual number of print dots printed on the area.

When the number of dots printed on each recording paper area is less than the set value, that is, when the wetting degree is less than the set value, the power supplied to the corresponding surface heater becomes zero and the heater is dried. Instead it is air dried.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of an ink jet printer according to the present invention will be described below with reference to the drawings. First, the overall structure will be described with reference to the perspective view of FIG. In the figure, an ink jet recording head (hereinafter, simply referred to as a recording head) 2 is guided along two parallel guide rails so as to be able to go straight in a direction A, and a belt 5 wound around a pulley 6 is driven by a motor 4. Driven through. On the other hand, the recording paper 8 is fed along the horizontal guide plate 7B by the feed roller 7 and the paper presser 7A at a right angle to the A direction. Since the recording paper 8 is covered on the front side (right side in the figure) of the feed roller 7, three rectangular surface heaters (heat generating plates) 20A, 20B, 20C indicated by broken lines are arranged side by side in the lateral direction, and a guide plate is provided. It is installed by being fitted into the hole made in 7B. That is, the recording paper 8 is fed out above this surface heater array. Although this surface heater array is a little inconvenient for reading the record, it can be installed close to the upper side of the recording paper 8.

Ink is supplied to the recording head 2 from a fixed ink container 14 through a flexible ink tube 15. Further, a protection device 10 is installed on the right inside of the U-shaped base frame 9 that holds the mechanical portion so as to be able to face the recording head 2. The protection device 10 is a device that wipes the nozzle surface of the recording head 2 or eliminates nozzle clogging, and is placed outside the printing area of the recording paper 8. To wipe the nozzle surface, a water-repellent silicone rubber wiper 1 for wiping the nozzle surface is used in the process of moving the recording head 2 to the right end.
2 and the ink absorbing sponge 13 function, and in order to eliminate the nozzle clogging, when the recording head 2 is moved to the right end portion, a suction cap 11 that can face the nozzle surface is provided.
(Communicating with an absorption pump (not shown)) functions.

FIG. 1 is a block diagram of an embodiment. In the figure, the recording head 2, the recording paper 8, the heaters 20A on each side,
Rows 20B and 20C are viewed from above. The distance from the printing position of the recording head 2 to the lateral side of the surface heater array is equal to the common vertical dimension of each surface heater, and the sum of the lateral dimensions of each surface heater is equal to the total recording width of the recording paper 8. In the drawing, the lateral dimensions of the respective surface heaters are set equal, but this is not always the case. Now, from the upper side of each heater,
Wetting by the ink printed on the recording paper areas 8A, 8B, 8C indicated by the one-dot chain line connected to the upper part of the printing area
The surface heater 20 is moved downward in FIG.
It will be dried while passing over A, 20B, 20C. Moreover, the amount of heat for drying is determined according to the actual number of dots printed on each recording paper area 8A, 8B, 8C only for the time from the position shown in the drawing until the corresponding surface heater overlaps with the corresponding surface heater. Is rational. After that, the subsequent recording paper area is similarly dried and heated. The heat quantity control for that purpose, that is, the control of the electric power supplied to the surface heater is performed as follows.

The print controller 21 sends a print pulse to the recording head 2 on the basis of a print command (not shown) (at the same time, the print head 2 also receives a lateral movement command, but this command is not shown. ). At the same time, the print dot counters 22A, 22B, 22C connected to the print control unit 21 count the number of dots printed on each recording paper area 8A, 8B, 8C. Depending on the number of counted dots, the heaters 20A, 20B, 20
The power to be supplied to C is determined. Hereinafter, also in the succeeding recording paper area, power is similarly supplied to the corresponding surface heater to perform dry heating.

The vertical and horizontal dimensions of the surface heater must be determined in view of the actual distribution of printing.
For example, the horizontal dimension or the number of divisions of the entire recording width is determined depending on the tendency of the print density, especially if the print density tends to be biased. Also, the vertical dimension is affected by the deviation of the print density and the wetting of the feed roller or other ink. It is also determined by the positional relationship of the members. Further, when the number of dots printed on each recording paper area is less than or equal to the set value, that is, when the degree of wetting is less than or equal to the set value, the power supplied to the corresponding surface heater can be set to zero. In other words, instead of drying with the heater, it is naturally dried.

By the way, a method of detecting the print density of the recording paper instead of counting the number of print dots as in the embodiment may be considered to obtain the optical density (brightness) by a sensor. However, the latter method is inferior to the method of the embodiment in terms of economy, composition, treatment and handling.

[0016]

According to the present invention, the following excellent effects can be expected. (1) The printed recording paper can be efficiently dried by the heater according to the print density, the print quality can be maintained, and the waste of electric power cost for heating can be saved. That is, since the heater drying is performed to a weak degree on the recording paper portion having a small print portion and to the strong degree on the recording paper portion having a large print portion, a reasonable running cost reduction of the printer can be achieved. (2) When the print density is particularly low, it is more rational because it is naturally dried instead of heater drying. That is, when the number of dots printed on the recording paper area is less than the set value,
That is, when the degree of wetting is lower than the set value, the power supplied to the corresponding surface heater is set to zero. Therefore, it is possible to support rational running cost reduction of the printer.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment according to the present invention.

FIG. 2 is a perspective view of an embodiment.

[Explanation of symbols]

 2 recording head 7 feed roller 7A paper holder 7B guide plate 8 recording paper 8A, 8B, 8C recording paper area 20A, 20B, 20C surface heater 21 print controller 22A, 22B, 22C print dot counter 23 power controller

Claims (2)

[Claims] 1. A printer for printing with an ink jet recording head which moves a recording paper while feeding the recording paper over the entire recording width, and a horizontal dimension common to each lateral dimension obtained by dividing the entire recording width of the recording paper into one or more. The rectangular surface heaters having the dimensions are arranged in a row in the horizontal direction, and the common horizontal side close to the printing location is separated from the printing location in the feeding direction by the same distance as the vertical dimension of the surface heater. While positioning at the location,
An array of surface heaters arranged in parallel and close to the surface of the recording paper; the same rectangular recording paper area that is connected to each surface heater begins to overlap with the surface heater as the recording paper is fed out, and only until the time of complete overlap , To generate heat according to the number of dots printed on each recording paper area,
An ink jet printer comprising: a power control unit that supplies power to each corresponding surface heater. 2. The ink jet printer according to claim 1, wherein when the number of dots printed on each recording paper area is less than a set value, the power supplied to the corresponding surface heater is zero. -Printer.