JP3036504B2 - Inkjet printer - Google Patents

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, and more particularly to an ink-jet printer for drying, for example, ink adhered on paper with warm air from a dryer.

[0002]

2. Description of the Related Art An example of this type of ink jet printer is disclosed in Japanese Patent Application Laid-Open No. 54-156536 [B41J 3/04], which was published on Dec. 10, 1979. In this ink jet printer, the drying time of the ink adhered on the paper is reduced by blowing hot air or warm air in a shape nearly parallel to the paper surface.

[0003]

In this prior art, since hot air or hot air is blown at a constant temperature and a constant air volume, there is a problem that printing quality varies due to differences in paper quality. For example, OHP (Over Head Pr
When paper print data to the Ojector), ink may adhere in large quantities to the paper surface, and dried it in strong hot air or warm air, it intends want ink flow.

[0004] The main object of therefore, the present invention is 1
An object of the present invention is to provide an ink jet printer that can optimally cope with a change in print density for each line .

[0005]

SUMMARY OF THE INVENTION The present invention is directed to a printing position.
Print by ejecting ink from a nozzle onto the paper
Ink jet printer, located downstream from the printing position
Is provided to blow hot air in the paper
Dries the ink attached to the paper at the remote drying position
Temperature and air volume differ depending on dryer and ink adhesion amount
Control data for setting at least one of the control data
Data storage means to check that printed lines have reached the dry position.
Detection means for outputting the control data according to the detection of the detection means.
Read the control data set in the data storage
Control dryer temperature and / or air flow
An inkjet printer including a control unit .

[0006]

When printing, the user sets the type of paper to be used (paper type), the number of sheets to be printed, and the like. When a print command is given, print data is buffered in a buffer memory in the ink jet printer, and printing is started. The number of dots in the print data for one line is counted by, for example, a dot counter, and the print density (ink adhesion amount) for each line is detected based on the count number. At least one of the optimal temperature and the flow rate of the warm air blown out from the dryer is determined for each line according to the ink adhesion amount for each line, and the ink adhered to the paper is dried. More specifically, for example, control data such as ROM
Control in data storage means, for example, in the form of a data table
If the data is set in advance and the detection means
When the control means detects that the first drying has reached the drying first, the control means controls the control.
Read the control data and control the dryer. In addition,
A number is assigned to each control data in the data table
In this case, the control means may be, for example, a memory area (data
Number is stored for each line in the
When the line reaches the drying position, the control data starts from that number.
And read the data to control the dryer.

[0007]

According to the present invention, ink adheres to each line.
Since at least one of the optimum temperature and the air flow of the dryer is determined for each line according to the amount , the ink is dried under the optimum condition, and the inconvenience such as the ink flow does not occur. The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

[0008]

Referring to FIG. 1, an ink jet printer 10 according to this embodiment includes a carriage 12 and an ink cartridge 14, and the carriage 12 is installed substantially at the center of the ink jet printer 10, and an ink cartridge 14 is provided.
Is mounted on the carriage 12. Carriage 12
Is moved in a direction perpendicular to the paper surface of FIG. 1 (the width direction of the inkjet printer 10). Accordingly, the ink cartridge 14 is also moved in the width direction of the inkjet printer 10. A nozzle 14a is provided on the lower surface of the ink cartridge 14, and the nozzle 14a ejects ink at a printing position A according to print data. Therefore, the print data is printed in the width direction of the inkjet printer 10. A pinch roller 16 is provided substantially at the lower right of the carriage 12.
The feed roller 18 is provided further below the pinch roller 16. The print paper (not shown) taken out by the paper feed roller 20 is transported to the print position A by the pinch roller 16 and the feed roller 18. The feed roller 18 is rotated by a feed motor (not shown). In this embodiment, the feed motor is constituted by a stepping motor or a pulse motor. The paper feed roller 20 is installed substantially on the right side of the carriage 12, and further on the right side of the paper feed roller 20 is a paper feed tray 22.
Is installed. The printing paper is taken out of the paper feed tray 22 by the rotation of the paper feed roller 20.

Further, the ink jet printer 10 includes a drier 24, and the drier 24 is installed substantially below and to the left of the carriage 12. The dryer 24 extends in the width direction of the inkjet printer 10 and is formed in a printing range. The dryer 24 is connected to a control circuit 26 described later.
At the drying position B, hot air is blown in the direction in which the printing paper is discharged. Therefore, the ink attached to the surface of the printing paper is
Dry uniformly.

The ink jet printer 10 further includes a host CPU 28, and the host CPU 28
Connected to. The control circuit 26 controls the operation of the inkjet printer 10 under the instruction of the host CPU 28,
Further, status information is given to the host CPU 28. When printing, the type of printing paper, the number of prints, and the like are set in the host CPU 28 by the operator.

As shown in FIG. 2, the control circuit 26 includes a CPU
The host CPU 28, a temperature control circuit 34, an air volume control circuit 36, a RAM 38, a dot counter 40, and a ROM 42 are connected to the CPU 32. The temperature control circuit 34 and the air volume control circuit 36 are incorporated in an ASIC. The temperature control circuit 34 applies a heater voltage to the heating wire 24a provided in the dryer 24, and the air volume control circuit 36 supplies a heater motor 24b provided in the dryer 24. Apply drive voltage. Therefore, the temperature and the amount of hot air blown out from the dryer 24 are controlled. A plurality of drivers (not shown) such as a feed driver and a carriage driver are connected to the CPU 32. The plurality of drivers are driven in accordance with instructions from the CPU 32, and status information of each driver is detected by the CPU 32. It is provided to the host CPU 28. RA
M38 is used as a buffer memory for holding print data. The ROM 42 stores a plurality of table data 42a of the temperature and air volume of the warm air blown out from the dryer 24, and the CPU 32 selects the table data 42a according to the paper type set by the user and the ink adhesion amount at the time of printing. I do. The temperature and air volume table data 42a are values obtained by experiments, and the respective table data 42a are numbered.

The dot counter 40 counts the number of dots of one line of print data to be printed. CPU32
Can detect the density of ink (the amount of ink attached) on the printing paper based on the count value (the number of dots) of the dot counter 40. The CPU 32 gives an instruction to the temperature control circuit 34 and the air volume control circuit 36 based on the selected table data 42a. Therefore, the heater voltage applied to the heating wire 24a and the drive voltage applied to the dryer motor 24b are determined.

The dryer 24 is operated when the ink-adhered portion reaches the drying position B, and is stopped when an eject command is given from the host CPU 28, that is, when all the ink-adhered portions pass through the drying position B. Then, when the ink adhering portion of the next printing paper reaches the drying position B, the dryer 24 is operated again. Further, since the print data of a plurality of lines is printed after the table data 42a is selected and before the dryer 24 is operated,
The number of the selected table data 42a is stored in a memory area 38a provided in the RAM 38. That is, the number of table data 42a for a predetermined row is held in the memory area 38a, and when the dryer 24 is operated, the table data is sequentially read by the CPU 32, and the newly selected table data 42a is sequentially written by the CPU 32. As described above, since the feed motor is formed of a stepping motor or a pulse motor,
The PU 32 can know the moving distance (the number of lines) of the printing paper based on the control pulse. That is, the CPU 32
Based on the control pulse, it is possible to know that the printing portion of the first line has reached the drying position B, that the printing portion of the next line has reached the drying position B, and the like. Therefore, the ink-attached portion is dried based on the table data 42a selected for each row.

The above-described operation is performed by the CPU 32 in accordance with the flowcharts shown in FIGS. As shown in FIG. 3, when a print command is given from the host CPU 28, the CPU 32 starts processing, and in step S1, the host CP
The information on the type of printing paper is read from U28. Subsequently, in step S3, the print data is buffered in the RAM 38, and printing is started in step S5. In a step S7, a selection process of the table data 42a is executed. In a step S9, it is determined whether or not the drying position B has been reached.
If "NO" here, the process returns to the step S7.
If "YES", the table data 42a of the print line to be dried is read in step S11, and the dryer 2 is read based on the table data 42a read in step S13.
Drive 4 In step S15, it is determined whether a line feed has been performed, that is, whether the printing paper has been conveyed by one line. If “NO” here, the process returns to the step S13, but if “YES”, the process returns to the step S1 shown in FIG.
At 7, it is determined whether an eject command has been given from the host CPU 28. Here, if "NO",
Returning to step S7 shown in FIG. 3, the table data 42a for the next print line is selected. On the other hand, in step S17, "Y
If "ES", the dryer 24 is stopped in step S19, and the printing paper is discharged in step S21.
At 23, it is determined whether or not the next print sheet is present, and "Y
If "ES", the process returns to step S5, but if "NO", the process ends.

As shown in FIG. 5, table data 42a
Is executed, the number of dots of the print data is counted in step S31. In a succeeding step S33, it is determined whether or not printing for one line is completed, and "NO" is determined.
If so, the process returns to step S31. If "YES", the amount of ink adhered is detected based on the number of dots in step S35. In the step S37, the table data 42a is selected according to the paper type and the ink adhesion amount, the number of the table data 42a selected in the step S39 is written in the memory area 38a, and the process returns.

According to this embodiment, the optimum temperature and amount of warm air blown from the dryer 24 are determined according to the type of paper and the amount of ink adhered, so that the ink is dried under optimum conditions. Inconvenience such as ink flow does not occur. In this embodiment, the temperature and the flow rate of the hot air blown from the dryer 24 are controlled for each line.
The control may be performed for each row or more.

In this embodiment, the number of dots of the print data is counted to detect the amount of ink attached. However, when a PC (Personal Computer) is used as a host, the bit map data of the print data is Since the data is developed by the PC, the amount of ink attached (ink density) can be detected in advance based on the bitmap data.
Furthermore, in this embodiment, the table data 42a (temperature and air volume) is determined according to the paper type and the ink adhesion amount, but at least one of the temperature and the air volume is determined according to at least one of the information of the paper type and the ink adhesion amount. It may be determined.

[Brief description of the drawings]

FIG. 1 is an illustrative view showing one embodiment of the present invention;

FIG. 2 is a block diagram of a dryer control circuit shown in FIG. 1 embodiment.

FIG. 3 is a flowchart showing a part of processing by a CPU shown in FIG. 2;

FIG. 4 is a flowchart showing a part of processing by a CPU shown in FIG. 2;

FIG. 5 is a flowchart showing a part of processing by a CPU shown in FIG. 2;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Ink-jet printer 12 ... Carriage 14 ... Ink cartridge 24 ... Dryer 26 ... Control circuit 28 ... Host CPU 32 ... CPU 34 ... Temperature control circuit 36 ... Air volume control circuit 38 ... RAM 40 ... Dot counter 42 ... ROM

Claims (2)

(57) [Claims] At a printing position, a nozzle injects ink onto paper.
Ink jet printers that eject and print
Te, provided downstream from the printing position, the sheet discharge direction temperature
Blow the wind and dry at a drying position away from the printing position.
Dryer for drying ink adhering to paper, temperature and air flow that vary depending on the amount of ink adhered
A control data storage means for presetting one control data
Step, detection to detect that the printed line has reached the drying position
Output means and the control data in response to detection by the detection means.
Read the control data set in the data storage
Control at least one of temperature and air volume of the dryer
An ink jet printer, comprising: 2. The control data storage means has an ink adhesion amount.
A plurality of data tables are set according to
Numbers are assigned to the plurality of data tables, and the control unit reaches the drying position from the printing position.
Data for reading and holding the numbers for each row before
The ink-jet printer according to claim 1 , further comprising a data holding unit .