JP3117694B2 - Image recording device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to an image recording apparatus.

2. Description of the Related Art In a conventional image recording apparatus, for example, an apparatus that performs recording by discharging ink from a recording head, the degree to which ink droplets landed on a recording medium bleeds into the recording medium (hereinafter referred to as bleeding rate). However, since recording has a great effect on recording quality, recording is performed on a recording medium with a special coating.

[Problems to be Solved by the Invention] However, even if a special coating is applied to the recording medium, there are some recording media that blur.

In addition, to apply a special coating to the recording medium, OH
A recording medium, such as a P film, in which ink bleeding is extremely small as compared with paper, has a problem in that the specific transparency is impaired, and the density of the recorded image becomes light overall.

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-described problems and achieve a higher recording density for a recording medium such as a rectangular OHP sheet having less ink bleeding than a recording medium such as plain paper where the ink tends to bleed. An object of the present invention is to provide an image recording apparatus capable of performing recording with a small memory capacity when performing recording.

Means for Solving the Problems In order to achieve such an object, the present invention relates to a recording medium having a rectangular shape in which the vertical direction is longer than the horizontal direction, the recording width in the vertical direction of the recording medium. An image recording apparatus which performs image recording on the recording medium by applying ink from the recording head while relatively scanning using a plurality of recording heads having a plurality of nozzles, wherein the recording of the recording head is performed. Scanning means for relatively scanning the plurality of recording heads and the recording medium arranged in the scanning direction such that the width direction and the scanning direction are different, and detecting information on the material of the recording medium Detection means for performing
A first recording density and a second recording density higher than the first recording density are determined according to the information on the material detected by the detection means.
Recording density control means for controlling the recording density so as to perform recording at any one of the recording densities, and the recording density controlled by the recording density control means is the second recording density. The plurality of recording heads and the recording medium are relatively scanned in a state where the recording medium is placed so that the longitudinal direction of the medium coincides with the scanning direction, and a plurality of nozzles of each recording head are scanned. When printing is performed by driving nozzles the number of which is equal to the recording width in the horizontal direction of the recording medium, the recording heads arranged side by side at a distance in the scanning direction are arranged along the scanning direction. In order to sequentially perform printing in the same upper area, the print head has a capacity sufficient to hold print information while delaying the print operation by each print head according to the distance between the print heads in the scanning direction. Memory and When the recording density controlled by the recording density control means is the second recording density, the recording medium is placed so that the lateral direction of the recording medium coincides with the scanning direction. Is provided with a recording operation control means for inhibiting a recording operation.

[Operation] In the present invention, the material of the recording medium is detected by the detecting means, and the recording density on the recording medium is controlled by the recording density control means based on the material detected by the detecting means.

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

FIG. 1 shows an embodiment of the present invention. This is an example of an ink jet printer.

In the figure, reference numeral 4 denotes an operation unit, which is constituted by a display device such as a key, an LED, and a liquid crystal, for inputting an instruction from an operator and displaying a state of the apparatus. 2 is a density control circuit, and a signal from the sequence controller 3
The recording density is switched based on the WD. The recording density is switched to 400 dpi when the signal WD is “0” and to 800 dpi when the signal WD is “1”.

Reference numeral 1 denotes a line buffer for synchronizing an external device and a printer via a dedicated reader or a general-purpose interface. 400dpi in synchronization with write clock WCK
Data with a recording density of
Data is read out in synchronization with K, and clock conversion between an external device and the inside of the printer is performed. Line buffer 1 has a built-in address counter, and has terminals WR and RR.
Are respectively input with a write system and a read system address reset signal, and the terminals WE and RE are respectively input with an enable signal of each system. The input image signal C of each color,
M, Y, and K are input in synchronization with control signals LSNC and LE input to terminals WR and WE, and are written for each line. The image signals C, M, Y, K read from the line buffer 1 are read by control signals PLS, PLE synchronized with the clock RCK output from the recording density control circuit 2.

The signal LE is an enable signal for image data input from the outside, and is valid only in a high level (H) section. signal
LSNC is a synchronizing signal of the signal LE and becomes H for one clock of the clock WCK immediately before the signal LE becomes H. The signals LE and LSNC are input to the WE and WR terminals of the line buffer 1, respectively, and are used to enable writing of the line buffer 1 and reset the write address.

12, 13, 14, and 15 are recording heads having 400 dpi multi-noise having a length of A4 lengthwise (297 mm). Reference numerals 5, 6, and 7 denote delay memories for correcting the distance between the recording heads 12, 13, 14, and 15 in the device configuration. It has a memory capacity that can be corrected when the distance between heads is recorded at 800 dpi in A4 width (210 mm) based on cyan C. Therefore, 800 dpi recording with A4 vertical feed is impossible. 8,9,10,1
Reference numeral 1 denotes an AND gate, which is a selection signal CEN, MEN, YEN, K for each of the recording heads 12, 13, 14, 15 outputted from the sequence controller 3.
A logical AND (AND) of EN and the image signals C, M, Y, K output from the line buffer 1 or the delay memories 5, 6, 7 is obtained.

Reference numeral 23 denotes a paper feed tray in which a recording medium 17 is stored.
Reference numeral 20 denotes a placement sensor for detecting the presence or absence of the recording medium 17. If the recording medium 17 exists, H is output,
If not, a low level (L) is output. Reference numeral 19 denotes a hinge, which is provided below the paper feed tray 23, and
The light path is moved by 17 so that the optical path is opened and closed.

Reference numeral 16 denotes a paper transport belt which transports a recording medium 17 such as a recording paper or an OHP film fed by a pair of rollers 18 at a predetermined speed. The recorded recording medium 17 is discharged from the discharge port B.

An OHP detection sensor 22 detects the light from the LED 21 on the facing surface and detects the material of the recording medium 17. In the case of blocking light such as paper, H is output and OH
In the case of a material such as P paper that transmits light, L is output.

Table 1 shows the relationship between the signal levels from the placement sensor 20 and the OHP detection sensor 22 and the presence / absence and material of the recording medium 17.

Next, the operation will be described based on the timing chart shown in FIG.

When one line of image data is written to the line buffer 1 by the signals LE and LSNC, the data is read from the line buffer 1 by the density control circuit 2. That is,
After detecting that the signal LE has changed from H to L, the read start synchronization signal PLS is output for one clock RCK to reset the read address of the line buffer 1, and then the signal PLE is set to H. The signal PLE is an enable signal similar to the signal LE, and the image signal is valid only during the period when the signal PLE is H.

When the signal WD is “0”, the recording density is selected to be 400 dpi, but the clock WCK is set to have the same frequency.

After that, when one line of data is written to the line buffer 1, the data is read out with a clock having substantially the same frequency, thereby enabling recording at 400 dpi.

On the other hand, when the signal WD is “1”, the clock RCK is set to be twice the frequency of the clock WCK. That is, one line of data written by the clock WCK is generated by the clock RCK having a frequency twice as high as that of the clock WCK.
First, one line is read and recorded by the recording head,
Then, by reading the same data again and recording it with a recording head, it is possible to record at twice the density of 800 dpi.

By repeating the above operation, the recording density control circuit 2
Switches the recording density.

When an H signal is output from the placement sensor 20, that is, when it is detected that the recording medium 17 is stored on the paper feed tray 23, based on the output of the OHP detection sensor 22,
The material of the recording medium 17 is determined by the sequence controller 3. When the output of the OHP detection sensor 22 is H, the recording medium 17 is determined to be paper, and the signal WD is set to “0”.
If it is L, it is determined to be an OHP film and the signal WD is set to "1".
To

At this time, the mounting direction of the recording medium 17 is displayed on the display unit on the operation unit 4 by the sequence controller 3. If the recording medium 17 is not placed at the proper position, a warning is issued and the recording operation is prohibited. Whether or not the recording medium 17 is placed at a regular position is detected by a second placement sensor (not shown).

That is, when the sequence controller 3 determines that the OHP mode is set, the A4 vertical feed at 800 dpi becomes impossible due to the memory capacity, and therefore, H is output from both the placement sensor 20 and the second placement sensor (not shown). If so, the operator is instructed to place it at a proper position, and the recording operation is prohibited.

In this embodiment, since the recording medium is configured as described above, even when recording is performed with the recording density changed, the memory capacity can be saved by selecting the moving direction of the recording medium, This has the effect of reducing costs.

In the present embodiment, an example in which the recording density is switched between 400 dpi and 800 dpi has been described.
Or 600 dpi. In this case, if the capacity of the delay memories 5, 6, and 7 has a memory capacity for 400 dpi recording of A4 vertical feed, 600 dpi A4 vertical feed is possible.
Recording in P mode is also possible.

Further, in the present embodiment, an example has been described in which switching between the paper mode and the OHP mode is performed based on the sensor output. However, the user may change the recording density from the operation unit 4.
In this case, if there is no correspondence between the placement direction of the recording medium 17 and the recording density, a warning may be given to the user based on the outputs of the placement sensor 20 and the second placement sensor.

[Effect of the Invention] As described above, according to the present invention, a rectangular OHP
When recording at a higher recording density on a recording medium, such as paper, with a small amount of ink bleeding than with a recording medium, such as plain paper, on which the ink easily bleeds, recording can be performed with a small memory capacity.

[Brief description of the drawings]

FIG. 1 is a block diagram showing an embodiment of the present invention, and FIG. 2 is a timing chart showing an example of the timing of each section shown in FIG. 1 ... line buffer, 2 ... density control circuit, 3 ... sequence controller, 4 ... operation unit, 5, 6, 7 ... delay memory, 8, 9, 10, 11 ... AND gate, 12, 13 , 14,15… recording head, 16… paper transport belt, 17… recording medium, 22… OHP detection sensor.

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04N 1/23-1/31 H04N 1/00-1/00 108 H04N 1/04-1/207 H04N 1/21 B41J 29/00-29/70

Claims (1)

(57) [Claims] An image forming apparatus according to claim 1, wherein a plurality of recording heads each having a plurality of nozzles corresponding to a recording width in a longitudinal direction of the recording medium are relatively scanned with respect to a rectangular recording medium whose longitudinal direction is longer than the horizontal direction. An image recording apparatus that performs image recording on the recording medium by applying ink from the recording head while arranging in the scanning direction such that a recording width direction of the recording head is different from the scanning direction. Scanning means for relatively scanning the arranged plurality of recording heads and the recording medium; detection means for detecting information on the material of the recording medium; information on the material detected by the detection means According to the first recording density and the second recording density higher than the first recording density.
Recording density control means for controlling the recording density so as to perform recording at any one of the recording densities, and when the recording density controlled by the recording density control means is the second recording density, The plurality of recording heads and the recording medium are relatively scanned in a state where the recording medium is placed so that the longitudinal direction of the medium coincides with the scanning direction, and a plurality of nozzles of each recording head are scanned. When printing is performed by driving nozzles the number of which is equal to the recording width in the horizontal direction of the recording medium, the recording heads arranged side by side at a distance in the scanning direction are arranged along the scanning direction. In order to sequentially perform printing in the same upper area, the print head has a capacity sufficient to hold print information while delaying the print operation by each print head according to the distance between the print heads in the scanning direction. Memory and When the recording density controlled by the recording density control means is the second recording density, when the recording medium is placed so that the lateral direction of the recording medium coincides with the scanning direction. An image recording apparatus, further comprising: a recording operation control unit for inhibiting a recording operation.