JPH02196662A - liquid jet recording device - Google Patents

Abstract

PURPOSE:To obtain an ink jet printer which can cope with any request of acceleration and high quality of recording by providing first control means for recording by using specific one of a plurality of discharge ports, second control means for recording by using all the discharge ports, and selecting means for selecting any of the first and second control means. CONSTITUTION:A CPU 120 controls according to an operation input, etc., with switch group 121. In order to perform the recording operation, any of high speed and high quality recording modes can be selected. When a print switch is depressed, the set state of a mode switch 121A is determined at a step S1. If it is set to the high speed mode, it is advanced to a step S3, and a set process of recording by using all the discharge ports is executed. A recording operation is executed at a step S5, and a high speed recording is performed in this mode. On the other hand, when the high quality mode is determined at a step S1, a set process for recording by using only any one row of discharge ports of a main scanning direction is executed at a step S7. When the recording operation is executed at a step S9, a high quality image recording is performed.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a liquid jet recording device (hereinafter referred to as an inkjet printer) that records information on a recording medium by jetting droplets of recording liquid (ink). be.

(Prior Art) FIG. 3 shows the mechanical configuration of essential parts of an inkjet printer.

In the figure, a platen designated by reference numeral 1 is rotationally driven by a line feed motor, such as a stepping motor, and conveys a recording medium (hereinafter referred to as recording paper) (not shown) such as paper, IP sheet, etc.

The presence or absence of this recording paper is detected by a paper sensor 9. The reference numeral 2 indicates an inkjet recording head (hereinafter abbreviated as recording head), which is composed of a plurality of ejection ports 30 for recording liquid such as ink, and is slidably mounted on a guide bar (not shown). The carriage motor 8, which is mounted on a carriage that is mounted, and is composed of, for example, a DC motor! ! ! It moves along the platen 1 via the belt 14 by force. A linear encoder 12 and an encoder sensor 13 are provided to detect the position of the recording head 2 in that case, and a home position sensor 11 is provided to detect the home position.

In order to recover from defective ink droplet ejection from the ejection openings 30 of the recording head 2, an ink suction cap 3 is provided that is moved by the drive of an auto-cap motor 6, and the operating position of the cap 3 is determined by a cap sensor IO. Detected.

FIG. 4 shows an example of a conventional recording head 2 installed in an inkjet printer having such a configuration.

Here, 30Y, 30M, 30C, and 30B are ejection ports provided corresponding to yellow, magenta, cyan, and black ink, respectively, and one ejection port is provided corresponding to each color. There is. Further, Pc is the arrangement pitch of the ejection ports.

However, as long as the head shown in FIG. 4 is used, there is a limit to meeting the recent demands for faster printing in general printers.

Therefore, in order to cope with such an increase in speed, the applicant has proposed a head having a so-called semi-multi-type ejection port arrangement (for example, Japanese Patent Laid-Open No. 73951/1983).

FIGS. 5 and 6 show an example of the configuration of such a semi-multi-type recording head, and respectively show a front view and a longitudinal section corresponding to one color of the recording head 2 applied to the configuration shown in FIG. 3. Shows a top view.

In these figures, Pn is the arrangement pitch of ejection port groups a to d corresponding to one color of ink.

Further, 21 is a glass tube with a discharge port formed at its tip, 23 is a common ink chamber that supplies ink to each glass tube 21, and 25
2 is an electromechanical transducer (piezoelectric element) that deforms in response to energization and applies discharge energy by deforming the glass tube 21 accordingly, and 2F is a positioning plate for the glass tube 21 or the discharge port a% d. It is.

When the recording head shown in FIGS. 5 and 6 is used, the fourth
4 for each color compared to when using the recording head shown in the figure.
Since it has multiple ejection ports, it is possible to record at about four times the speed.

FIG. 7 shows a printing state of a printer using the printing heads shown in FIGS. 5 and 6. FIG. Here, P is the recording pitch (for example, Pn=3xP), and the horizontal direction in the figure (
The number n in the main scanning direction) indicates the number of ink droplets (indicated by small circles) recorded after n main scannings, and the number n in the vertical direction (sub-scanning direction) indicates the second main scanning. The arrow attached to each value indicates the moving direction of the main scan, and the number inside the small circle indicates that the droplet was recorded in the second main scan. In FIG. 2, main scanning is performed seven times to record an effective recording area A in the sub-scanning direction.

(Problem n to be solved by the invention) As described above, the recording head 2 having the configuration shown in FIG. Since it is extremely difficult to manufacture a recording head according to the specifications, problems often arise in performing high-quality recording.

In other words, as shown in FIG. 6, each discharge port is provided by processing a part of the thin glass tube 21 to make it even thinner, so it is possible to achieve highly accurate alignment between the center of the glass tube z1 and the center of the discharge port. This is because, even if the glass tubes 21 are arranged using the highly accurate positioning plate 27, it is difficult to maintain the position of the discharge ports with high accuracy. As a result, streaks in the main scanning direction occur in printed characters and images, degrading the quality of the characters and images.

Furthermore, there may be a problem with the feeding pitch accuracy of the recording medium in the sub-scanning direction (in Figure 7, the accuracy when transporting 4 dots in one sub-scanning), which also affects image quality. This was causing deterioration.

By the way, the above-mentioned highly accurate positioning generally means lOμ
It is said to be less than about m. For example, 160 D
When recording one pixel with 1 dat of each color ink droplet at the density of PI (dot per 1 nch), P-15
It becomes 8.75 μm. At this time, if there is a deviation 4 in the position of the ejection port of more than 10 μm, streaks will occur in the main scanning direction.

Further, even if the positioning of the ejection ports is highly accurate, similar streaks occur when the flight path of ink droplets ejected from a particular ejection port is tilted in the sub-scanning direction.

On the other hand, in the recording head shown in FIG.
Since only a book ejection port is provided, the positional deviation of each color in the main scanning direction does not pose much of a problem in the output recorded image, and the image quality is high.

That is, in a printer using a semi-multi-head configured as shown in FIG. 5 in order to cope with higher speeds, image quality deteriorates, while in a printer using a recording head as shown in FIG.
Although high-quality images can be obtained, contradictory problems have arisen in that the speed is low.

SUMMARY OF THE INVENTION An object of the present invention is to provide an inkjet printer that can solve these problems and meet the demands for higher speed and higher quality recording.

[Means for Solving the Problems] To this end, the present invention has a liquid jet recording head in which a plurality of ejection ports are arranged in a predetermined direction, and the liquid jet recording head is arranged in a main scanning direction different from the predetermined direction. In a liquid jet recording device that records information while moving, a first control unit causes recording to be performed using a specific one of a plurality of ejection ports, and a first control unit that causes recording to be performed using all of the ejection ports. It is characterized by comprising a second control means and a selection means for selecting either the first control means or the second control means.

(Function) According to the present invention, when performing printing using a print head having a plurality of ejection ports for ink of a certain color, for example, it is possible to appropriately select the first or second control means. . In other words, if the second control means is selected, high-speed recording is possible by effectively using all the ejection ports, while by selecting the first control means, high-quality recording is possible by using only specific ejection ports. .

〔Example〕

Hereinafter, the present invention will be described in detail with reference to the drawings.

FIG. 1 shows an example of a control system of an inkjet printer according to an embodiment of the present invention, and specifically, it is applicable to the configuration shown in FIG. 3 in which a recording head 2 as shown in FIG. 5 is mounted.

In the figure, 120 is a CPU in the form of a microcomputer, for example, which executes a processing procedure that will be described later with reference to FIG. The CPU 120 performs the following control operations in response to operation inputs performed by a switch group 121 provided on an operation panel (not shown). That is, with reference to the human power from the encoder sensor 13 and the home position sensor 11, the drive of the carriage motor 8 is controlled via the DC servo forward/reverse circuit 122, and the line feed motor is controlled via the stepping motor drive circuit 123. The recording data D is sent to the head driver 124.
The recording head 2 is driven by the head driver 124. Further, other mechanisms (not shown) are also controlled in response to inputs from other sensor groups 125.

Based on this configuration, the recording operation is started by pressing the print switch in the switch group 121, and after confirming the presence of recording paper by the output of the paper sensor 9, the line feed motor 7 is activated. is driven several steps, the platen 1 rotates, and the recording paper is set at the recording start position. Subsequently, the carriage motor 8 is driven to reciprocate the recording head 2, and in synchronization with this, the line feed motor is driven to feed the recording paper line by line.

During this time, a drive signal corresponding to print data is applied from the head driver 24 to the print head 2, the print head 2 is driven, ink droplets are ejected from the ejection ports 30, and characters and images are recorded.

In this recording operation, in this example, it is possible to select either a high-speed recording mode or a high-quality recording mode. Further, the switch group 121 is provided with a mode switch 121^ in order to accept mode selection by the operator.

FIG. 2 shows an example of the recording processing procedure according to this example.

As described above, when the print switch in the switch group 121 is pressed, this procedure is started, and first, in step Sl, the setting state of the mode switch 121A is determined.

Here, if the high speed mode is set, the process advances to step S3, and a setting process for performing recording using all ejection ports is executed. That is, for example, processing is performed so that print data is developed in a buffer provided in the head driver 124 corresponding to all the ejection ports, and processing is performed so that all the ejection ports can be driven during printing. and,
A recording operation is performed in step S5, and in this mode, all ejection ports are used, so high-speed recording is achieved.

On the other hand, if it is determined in step 51 that the high image quality mode is selected, in step S7, only one row of ejection ports in the n direction (main scanning direction), that is, one ejection port for each color, is used. Executes the setting process for recording. That is, for example, processing to develop print data into a buffer corresponding to a selected row of ejection port groups, or processing to enable only that one row of ejection port groups to be driven during printing. etc. and,
If the printing operation is executed in step S9, high-quality printing is achieved because only one row of ejection port groups is used in this mode.

That is, according to this embodiment, the mode switch 121A
Since high-speed recording or high-quality recording is possible depending on the selection, an inkjet printer that can accurately meet the operator's demands can be realized.

In the above embodiments, a printer using a semi-multi-head having four ejection ports each as shown in FIG. 5 has been described, but an inkjet printer using a recording head having two or more ejection ports for each color Of course, similar recording control can be applied to a printer.

Furthermore, in the upper part, we have described the case where the present invention is applied to an inkjet printer that has a group of ejection ports corresponding to yellow, magenta, cyan, and black inks and is capable of multicolor recording. Needless to say, is optional.

Furthermore, although the recording head using a piezoelectric element is shown in the upper part, the form of the ejection energy generating element is not limited to this. For example, the form of the ejection energy generating element is not limited to this. Of course, it may also be a head.

(Effects of the Invention) As described above, according to the present invention, in an inkjet printer using a recording head having a plurality of ejection ports arranged in the sub-scanning direction for predetermined ink, high-speed print mode and high-quality print In high-speed print mode, all ejection ports are used effectively, while in high-quality mode, printing is performed using only one ejection port for the ink. Therefore, it is now possible to select either high-speed recording or high-quality recording as desired.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a control system of an inkjet printer according to an embodiment of the present invention, FIG. 2 is a flowchart showing an example of the recording control procedure, and FIG. 4 is a recording applied to the configuration of FIG. 3. 5 and 6 are respectively a front view and a vertical sectional view showing an example of a configuration of a semi-multi-type recording head that can be applied to the configuration of FIG. 3, and FIG. 7 is a front view showing a conventional example of a head. FIG. 7 is an explanatory diagram for explaining a printing mode using the print head shown in FIGS. 5 and 6. FIG. 2... Inkjet recording head, 7...
Line feed motor, 8... Carriage motor, 21... Glass tube, 25 -... Piezoelectric element, 30.30Y, 30M, 30G, 30B...
Discharge port, 120 - CPU 121... Switch group, 121^... Mode switch, 124... Head driver, 125... Sensor group. Pregnancy 1 Fig. 2 Ishikjiet Alink Fertility area 14A fl: J configuration Rei 2 Fig. 3 Fig. 6 Fig. 5 n → ■ Fig. 7

Claims (1)

[Claims] 1) A liquid jet recording head having a plurality of ejection ports arranged in a predetermined direction, and recording information while moving the liquid jet recording head in a main scanning direction different from the predetermined direction. In a liquid jet recording apparatus, a first control means causes recording to be performed using a specific one of the plurality of ejection ports; a second control means causes recording to be performed using all the ejection ports; A liquid jet recording apparatus comprising: a selection means for selecting either the first control means or the second control means. 2) The liquid jet recording apparatus according to claim 1, wherein the liquid jet recording head discharges the liquid using mechanical energy. 3) The liquid jet recording apparatus according to claim 1, wherein the liquid jet recording head discharges the liquid using thermal energy.