JPH0214159A - Recording apparatus - Google Patents

Abstract

PURPOSE:To prevent the occurrence of white stripes at the time of recording of a first block by a method wherein image data are not recorded at a record timing accompanying at least first conveyance of recording paper, and corresponding 1-line recording of the image data is conducted at a subsequent record timing. CONSTITUTION:When a recording start instruction is received from CPU 102, a BUSY signal to a main control element 100 is turned to be '1' to prohibit a subsequent recording start instruction from the main control element 100. Next, a pointer PP to be recorded is set at '4'. This is made for the purpose of making record in the direction of sub-scanning with a density being rougher four times than the minimum record density by a recording element 110 so as to record one line of an image by four lines. Next, whether or not recording is skipped by high-speed conveyance of recording paper because of all the line data preceding by one being a white line, for instance, is checked up from whether a SKPF flag is ON or not. When it is not ON, a mechanism element 117 is driven to convey the recording paper for one step and recording for one line is executed. This recording operation is conducted by electrifying each of four divided blocks of a thermal head 115 for 0.6ms at the maximum, and therefore a time of about 2.4ms is required for recording one line.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a recording apparatus that has a line head equipped with dot recording elements for one line and records on a line-by-line basis.

[Prior Art] Conventionally, for example, in a recording section of a facsimile machine capable of recording at a dot density of 15.4 lines/mm in the sub-scanning direction,
Recording may be performed at a recording density of 3.85 lines/mm. In such a case, the recording density in the sub-scanning direction will be approximately 4 times coarser, so the minimum feed step of the recording unit, l/1
5.4 mm, it is necessary to move the recording paper in the sub-scanning direction by four steps to record one line. At this time, the same data is recorded in the main scanning direction for each step of movement, and the 4 lines recorded with the same content are 3.85
One line of data was recorded at a recording density of line/mm. At this time, 1715.4m
Assuming that the time required to record each line when recording at a recording density of m is 2.5 ms, the recording time for one line when recording at a density of 173.85 mm is four times that, so it is 10 ms. .

When recording by changing the recording density in this way, for example, if one line of 3.85 lines/mm is all white data (data with no recording dots), the recording operation for that line is unnecessary. Therefore, by driving the stepping motor for conveying the recording paper at high speed, the recording paper can be moved 173.85 mm in 5 ms, which is half the time required for recording. This can shorten the recording time for one page, but the first line that has recorded data after skipping all white data lines (or the recorded data after continuously skipping white data lines) 3), record 4 lines with 10m5 as described above.
Recording was performed at a recording density of 85 lines/mm.

[Problems to be Solved by the Invention] However, after the stepping motor moves at high speed, such as when skipping the white data line, the tracking of the recording paper is poor and damping of the motor occurs, so the white data When recording the first line after skipping a line, there is a problem in that a white stripe pattern appears between the four lines that make up one line, which deteriorates the quality of the reproduced image.

FIG. 3 shows an example of occurrence of disturbance in a conventional reproduced image. In FIG. 3, the horizontal axis indicates time t (ms), and the vertical axis indicates moving distance S (mm) in the sub-scanning direction. In the figure, the broken line shows the relationship between the time and travel distance when the recording paper is ideally transported by the drive of the paper feed motor, and the solid line shows the relationship between the time and travel distance when the recording paper is ideally transported by the drive of the paper feed motor, and the solid line shows the relationship between the time and travel distance when the recording paper is ideally transported by the drive of the paper feed motor, and the solid line shows the relationship between the time and travel distance when the recording paper is ideally transported by the drive of the paper feed motor. , which shows the relationship between the time and movement of the recording paper actually moved. In this way, the entire white line is skipped for the first 5ms after the motor starts driving.
The recording paper is driven in 4 steps at 00pps, and the period from the next 5ms to 15m5 indicates the time during which one line is actually recorded.During this time, the recording paper is conveyed at a speed of 400pps to complete one line (1/3.85mm). 4 lines (1/15.4 mm) corresponding to 1/15.4 mm are recorded.

The dotted line 30 shows the recording state when the recording paper is ideally moved, and four lines are recorded without gaps in the sub-scanning direction. On the other hand, numeral 31 indicates a state in which recording is performed by actually moving the recording paper, which is indicated by a solid line. As is clear from the figure, since recording 32 of the first line and recording 33 of the second line are performed before the recording paper has fully moved, this causes white stripes to appear in the reproduced image. Furthermore, since the thermal line head is actually driven by dividing into a plurality of blocks (for example, four blocks), white stripes are particularly likely to occur when printing the first block during printing in the main scanning direction.

The present invention has been made in view of the above-mentioned conventional example, and an object of the present invention is to provide a recording device that improves the recording quality of reproduced images.

[Means for Solving the Problems] In order to achieve the above object, the recording device of the present invention has the following configuration. That is, this is a recording device that records line by line using a line head, and includes a conveying means that conveys the recording paper in the sub-scanning direction, and a conveying means that conveys the recording paper multiple times, and the recording timing that accompanies each conveyance. means for forming an image for one line of image data by recording the same data each time; and after the recording paper is conveyed at high speed by the conveying means, the image data is recorded at a recording timing that accompanies at least the first conveyance of the recording paper. and recording means for recording one line of the corresponding image data by recording the corresponding image data at a subsequent recording timing without recording.

According to another aspect of the present invention, the recording means makes the recording density darker when recording the image data than during normal recording.

[Operation] In the above configuration, the recording paper is conveyed in the sub-scanning direction multiple times, and the same data is recorded at each recording timing associated with each conveyance to record one line of image data. After the recording paper is conveyed at high speed by this conveyance means to perform image formation, the recording means does not record image data at the recording timing associated with at least the first conveyance of the recording paper, but records the corresponding image data at the subsequent recording timing. One line of the corresponding image data is recorded.

According to another aspect of the present invention, the recording means makes the recording density 71 higher when recording the image data than during normal recording.

[Embodiments] Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

[Description of Facsimile Apparatus (FIG. 1)] FIG. 1 is a block diagram showing a schematic configuration of a facsimile apparatus according to an embodiment.

In the figure, 100 is a main control unit that controls the entire facsimile machine, and a CPU 102 that executes various controls according to the control program and various data shown in the flowchart of FIG. 4 stored in ROM10I, and a work area of the CPU 102. It includes a RAM 103, etc., which is used as a storage device and temporarily stores various data. 104 is a league unit that photoelectrically reads and inputs the transmitted manuscript; 105 is an operating panel such as a keyboard that is operated by the operator to input various operating instructions; and a display unit such as a liquid crystal display that displays messages to the operator. This is an operation section equipped with a control panel. 106 is an encoding unit that encodes the transmitted original image data from the league unit 104 into, for example, an MH code, and 107 is a decoding unit that decodes the received image data and converts it into image data. 10
Reference numeral 8 denotes a transmitting/receiving unit that performs transmission/reception control with a communication line 109 such as a public line.

110 is a recording unit that forms an image of image data; 111 is a control unit that controls the recording unit 110; a CPU 112 such as a microprocessor;
ROM11 that stores the control program of PU112
3. RAM 1 which is used as a work area for the CPU 112 and has a pointer PP, a flag 5KPF, etc. which will be described later.
Contains 14 mag. For example, 115 has a length corresponding to the width of 84 size, and one line has 2048 dots (2048 dots).
This is a thermal head consisting of several heating resistors. Then, these 2048 dots are divided into 4 blocks of 512 dots each, and each block is energized to generate heat for recording. In this embodiment, each block is driven to generate heat for a maximum of 0.6 ms, and the recording time of one line is 2.4 ms at maximum. 116 is a temperature detection sensor such as a thermistor that detects the temperature of the thermal head 115. Reference numeral 117 denotes a conveying mechanism section that conveys the recording paper, and includes a stepping motor 118 for feeding the recording paper, its drive system mechanism, and the like.

With the above configuration, when receiving and recording image data, the main control section 100 transfers one line of image data to be recorded and a clock signal synchronized therewith to the thermal head 115 via the signal line 120. When the data of one line to be recorded is transferred to the thermal head 115 in this way, a recording start command is output to the control section 111 of the recording section 110.

When the control unit 111 receives a recording start command from the main control unit 10.0, it determines the energization time of the recording reservoir of the thermal head 115 based on the temperature signal from the sensor 116, and causes the thermal head 115 to generate heat for each block. Drive to record on recording paper.

[Description of Thermal Head (Fig. 2)] Fig. 2 is a block diagram showing the configuration of the thermal head 115 of the embodiment.

Reference numeral 200 denotes a shift register that stores one line, ie, 2048 bits of serial dot data.
image data is input as serial data 202 in synchronization with a clock signal 201. 203 is a latch circuit that latches the data 2048 of the shift register 200 using the latch signal 204; 205 is a latch circuit that inputs the recording data from the latch circuit 203 and the strobe signal 206 from the control unit 111 to control the corresponding heating resistor group; This is a driver circuit that drives each of blocks (1) to (TV).

[Explanation of operation of main control unit (Figs. 1 to 4)] Fig. 4 is an operation flowchart of one page recording process by the CPU and 102 of the main control unit 100. The control program for executing this process is stored in ROM101. has been done.

This process is started by reception of image data or copy processing, etc. First, in step Sl, the received image data or read original image data is converted into a serial signal, and the shift register 200 of the thermal head 115 is sent in synchronization with the clock signal 201. Transfer to. In step S2, it is determined whether the transfer of one line of image data to the shift register 200 has been completed, and if the data transfer of one line has not been completed, the process returns to step S1.

When the transfer of one line of image data is completed and stored in the shift register 200, the process advances to step S3, and the recording section 1
10, the control unit 111 of the recording unit 110 determines whether the thermal head 115 is activated or not.
Check whether recording is in progress. If recording is in progress, wait until the recording process is finished, and when the recording is finished (no longer busy), the process advances to step S4.

In step S4, the latch signal 204 is output and the image data stored in the shift register 200 is transferred to the latch circuit 2.
Latch to 03. Then, in step S5, a recording start command is output to the recording unit 110, and in step S6, it is checked whether recording of one page has been completed, and if it has not been completed, step S
Return to step 1 and transfer the image data of the next line to thermal head 1.
Transfer to 15.

[Explanation of the operation of the control section 111 (FIGS. 1 to 5)] FIG. 5 shows an operation flowchart of the control section 111 of the recording section 110 of the embodiment. Note that the CPU 112 that executes this control
The control program is stored in the ROM 113.

When a recording start command is received from CPUIO2 of the main control unit 100 in step SIO, the main control unit 1
Set the busy signal to 00 to “1”. This prohibits the next recording start command from the main control unit 100. In step SL2, the recording pointer PP is set to "4". This is because, as described above, the recording unit 110 records in the sub-scanning direction at a density that is four times coarser than the minimum recording density in the sub-scanning direction, so that one line of the original image is recorded in four lines.

In step S13, since the previous line data were all white lines, the 5KPF flag is used to determine whether the recording paper has been conveyed at high speed and the line has been skipped without being recorded. Check whether it is on or not. If it is not on, that is, if a normal recording operation is being executed in the previous line, the process advances to step S14, where the mechanism section 117 is driven to transport the recording paper one step, and in step S15, the recording paper is 1917 minutes of transport is recorded. In this recording operation, the thermal radar 115 is divided into four blocks and each block is energized for a maximum of 0.6 ms to perform recording, and it takes about 2.4 ms to record this 1 line.

When the recording of 1917 minutes is completed in this way, step S16
Then, the pointer PP is decremented by 1. In step S17, it is checked whether the pointer PP is "0", and if it is not "O", the process returns to step S14 again and the recording paper is conveyed by one line and the same data is recorded. When one line of image data has been recorded in this manner, the process advances to step S25, where the busy signal is turned off and the process returns to step S10.

On the other hand, if the 5KPF flag is on in step S13, the process proceeds to step 318, where the 5KPF flag is turned off, and in step S19, the mechanism section 117 for transporting the recording paper is driven to transport the recording paper by one line. In step S20, it is checked whether the pointer PP is "2" or less, and if it is not "2" or less, in step S21 the wait time is about 2.5 ms, and in step S2
Proceed to step 2. This means the operation of waiting for a time corresponding to the recording time in step S22, which will be described later.

If the pointer PP is "2" or less in step S20, the process advances to step S22, and recording of 1 line is performed. This operation is the same as the recording process in step S15. The time required for this recording is 2.4 ms per line. In step S23, the pointer PP is decremented by 1, and in step S24, the above-described operation is repeated until the pointer PP becomes "0" and recording of one line is completed.

If a recording start command is not input in step SIO, the process advances to step S26 to see if it is a skip command. This skip command is input from the main control unit 100 when all data of the next recording line is white, that is, there are no recording dots. When this command is input, the process advances to step S27 and the 5KPF flag is set. along with pointer PP
Set "4" to 0. Next, in step S28, one line of recording paper is conveyed, and in step S29, it is waited for 1.25 m5. Then, in step S30, the pointer PP is set to -
1, and the aforementioned recording paper feed is executed until PP becomes "O" in step S31.

Note that the recording paper feeding speed at this time was 800 pps.

In this embodiment, one line of image data is formed by 4 lines during normal recording, and the blank feed after high-speed skip due to white lines etc. is set to 2 steps, and during recording, it is set to 2 steps, but this is not limited to this. This means that the normal recording time is n (integer) steps, and the blank feed step is m (man
), the recording step may be set to (nm).

In addition, in this embodiment, the 2-step idle feed after high-speed feed is 2.5 ms (400 pps), and the recording step is 2.5 ms (400 pps).
Although it is set to 5ms (400pps), it is not limited thereto, and by reducing the time for two steps of idle feeding, the printing time for one line can be shortened.

Furthermore, in this embodiment, data that should be recorded four times (line) is recorded only twice in the recording line after high-speed skip processing, so the recorded line becomes somewhat thinner. In order to prevent this, it is conceivable to apply more energy to the thermal head during these two recordings than when recording other lines.

In addition, in this embodiment, when moving the recording paper at high speed,
Although the description has been made for the case of skipping a line where there is no recorded data, the present invention is not limited to this. For example, the operation may be performed after high-speed movement of the recording paper at a page break or when starting a page, etc. Of course, it is possible.

Further, in the above configuration, the main control section and the control section for the recording section are separated, but it is also possible for one CPU to control them all. Also, the recording linear density is fine mode (7,71 inch).
The same applies to the case of (e/mm).

As explained above, according to this embodiment, by performing a blank feed of the recording paper before recording the first line after the recording paper moves at high speed, the motor speeds during recording and during high-speed movement are different. Disturbances in reproduced images due to uneven movement of the recording paper can be prevented.

Further, according to this embodiment, it is possible to shorten the time required for the skip operation of the recording paper and the recording of one line after the skip operation, and the recording time in the normal recording mode is shortened.

Furthermore, although this embodiment has been described in the case of a thermal line printer, the present invention is not limited thereto, and can of course be applied to a general line printer having a recording paper conveyance system like this embodiment.

[Effects of the Invention] As described above, the present invention has the effect of improving the quality of reproduced images after the recording paper is conveyed at high speed.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the schematic configuration of the facsimile machine of the embodiment, Fig. 2 is a diagram showing the structure of the thermal head of the embodiment, and Fig. 3 shows the drive signal of the conventional stepping motor for feeding the recording paper and the actual FIG. 4 is a flowchart showing the operation of the main control section when printing one page, and FIG. 5 is a flowchart of the operation of the control section of the recording section. In the figure, 100... Main control unit, 101... ROM, 1
O2...CPU, 103...RAM, 104...
League section, 105... Operation section, 106... Encoding section, 107... Decoding section, 108... Transmitting/receiving section, 10
9... Communication line, 110... Recording section, 111...
Control unit, 112...CPU% 113...ROM,
114...RAM, 115...Thermal head, 1
16...Temperature sensor, 117...Transportation mechanism section, 11
8...Motor, 200...Shift register, 201
...Shift Kurotsuta, 202...Serial data,
203...Latch circuit, 204...Latch signal, 2
05... Driver circuit, 206... Strobe signal, 207... Heat generating resistor. Patent applicant Canon Co., Ltd. Figure 4 Figure 5B

Claims (2)

[Claims] (1) A recording device that records line by line using a line head, which includes a conveyance means that conveys the recording paper in the sub-scanning direction, and a conveyance means that conveys the recording paper multiple times, and records that accompany each conveyance. means for forming an image for one line of image data by recording the same data at each timing; and after the recording paper is conveyed at high speed by the conveyance means, the image data is recorded at a recording timing that accompanies at least the first conveyance of the recording paper. 1. A recording apparatus comprising a recording means for recording one line of corresponding image data by recording corresponding image data at a subsequent recording timing without recording the corresponding image data. (2) The recording apparatus according to claim 1, wherein the recording means is configured to make the recording density darker when recording image data than during normal recording.