JPH0746379A - Picture copying device - Google Patents

Abstract

PURPOSE:To provide a picture copying device with high speed and high picture quality by using the maximum capacity of the device. CONSTITUTION:At the time of copying at a standard speed, a reading means 211 based upon an optical sensor executes main scanning for reading N times within one sub-scanning operation, a signal processing means 221 validates a read picture signal once out of N times based upon a selection signal outputted from a mode control means 401 and a recording means 311 provided with a recording head executes one main scanning operation in each sub- scanning. At the time of copying at an N-times speed, a sub-scanning speed is multiplied by N, the reading means 211 executes one main scanning operation for reading within one sub-scanning, the signal processing means 221 always validates the read picture signal based upon the selection signal from the means 401 and the recording means 311 executes one main scanning operation in each sub-scanning.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copier having either an image reading means or a thermal recording means for copying a read image on a recording sheet, or a facsimile machine having a copying function. Image copying apparatus, in particular,
The present invention relates to an image copying apparatus in which the reading / recording speed required for copying operation is variable.

[0002]

2. Description of the Related Art Generally, thermal recording of an image is performed by supplying thermal energy from a thermal recording head to a thermal recording paper or thermal recording paper.
A method is known in which thermal energy is recorded as an image using a recording medium that is a combination of thermal transfer ink and recording paper. The density of the image printed on the recording paper is determined by the recording energy applied to the head (= applied power x application time), the head temperature and the environmental temperature, and the applied recording energy is controlled by controlling the application time. Done in.
Therefore, continuous recording can be performed as long as the period is equal to or longer than the application time at which the required recording energy (recording energy for obtaining the print density required for recording) can be obtained. Further, the obtained print density is affected by the head temperature and the environmental temperature. The lower the temperature, the higher the required recording energy, and the higher the temperature, the lower the required recording energy.

From the above facts, as a technique for minimizing the heat-sensitive recording time, the temperature of the head is detected, and the recording cycle is lengthened as the detected temperature becomes lower, and as the detected temperature becomes higher. There is an example of a thermal recording method for shortening the cycle (Japanese Patent Publication No. 55-10383, Japanese Patent Publication No. 4-1206).
Issue).

On the other hand, in order to read an image, generally, an image sensor using a photoelectric conversion element such as a CCD is combined with a light source, and spatial sampling and time sampling are performed.
Convert the image on the manuscript into electrical signals (Mitsuo Oshima: "How to select and use image sensors" by Nikkan Kogyo Shimbun, ISBN
4-526-01811-2, Sho 60).

The signal output of the image sensor has the following features.

(1) The output is an amount obtained by time-integrating the photoelectric conversion amount in order to accumulate the photoelectrically converted charges for a certain period of time.

[0007]

## EQU1 ## Output (Vout) ∝Light intensity (H) × Storage time (Tint) (2) The output has a saturation characteristic. (3) The sensitivity and saturation output of the sensor hardly change with temperature.

That is, since the light intensity is constant as long as the light source is used in a constant state, the cycle (accumulation time) for reading an image satisfactorily by the image sensor is constant within the range where the output is not saturated. , It is not affected by ambient temperature.

As described above, the recording cycle of the thermal recording is variable, but the reading cycle of the image reading by photoelectric conversion is constant, so that the recording operation requires a long recording cycle in the copying operation. In this case, adjust the intensity of the light source for reading according to the recording cycle,
If a long read cycle is required, the recording voltage is adjusted according to the read operation so as to obtain a predetermined recording energy, and the cycle of the copy operation, that is, the copy operation speed, is read or recorded. It was adapted to the one with low ability. However, in general, such a copying operation speed, that is, the cycle of the copying operation is determined by the recording cycle, not the reading cycle. In other words, the recording cycle is largely related to the power supplied to the head, but when trying to keep the total power consumption of the image copying apparatus low, there is a limit other than the device capability such as the power supply capacity. The cycle was determined by the recording cycle.

[0010]

As described above,
In the prior art, the copy operation speed, that is, the cycle of the copy operation is determined by the recording cycle. Moreover, there is only one type of such copying operation speed in order to maintain good image quality.

However, the recording cycle may be shortened without deteriorating the image quality under the following conditions.

(1) The recording cycle also changes depending on the sensitivity of the recording medium. The higher the sensitivity, the shorter the recording cycle can be. (2) As described above, the higher the head temperature, the shorter the recording cycle.

That is, when the recording medium has high sensitivity or the head temperature rises, the image quality does not deteriorate even if the recording cycle is shortened. Therefore, the copy operation cycle is shortened in accordance with the recording cycle. However, there is no problem even if the copy operation speed is increased, but as described above, in the past, there was only one kind of copy operation speed, so the copy operation speed could not be increased so much, and therefore, the apparatus There was a problem that he was not fully using his ability.

According to the experiment, when recording is performed at a high speed at a cycle of 5 ms per line, the recording energy to be applied per line is a cycle of 10 ms when recording at a cycle of 10 ms per line. In the case of 70% to 80% of the recording energy required, it is known that sufficient color development can be obtained.

When the user makes a copy, the following requests can be considered. (1) I want a high-quality copy. (2) I want to shorten the time for copying (I want an image copying machine with a high-speed copying operation).

However, if both high speed and high image quality are required, the image copying apparatus itself becomes expensive. Therefore, if the condition of a cheaper apparatus is added, the image can be copied at a high speed even if the image quality is slightly deteriorated. There is a demand for a copying machine, but the conventional technology has a problem that these requirements cannot be satisfied.

Further, in the image copying apparatus, the reading means converts the analog output of the sensor into digital data and the analog output of the thermistor which detects the substrate temperature of the recording head into digital data. An A / D converter is required, but it is desirable to be able to use both of them in order to reduce the cost of the device. However, in a copy operation in which both reading and recording operations are performed at the same time, since the A / D conversion of the sensor output and the A / D conversion of the thermistor output are processed in time series, there is an obstacle to performing the copy operation at high speed. Becomes

A first object of the present invention is to provide a high-speed, high-quality image copying apparatus by solving the above problems and making the best use of the capability of the apparatus itself. Also,
A second object of the present invention is to provide a low cost and high speed image copying apparatus.

[0019]

In order to achieve the above first object, as first means, thermal recording means and recording control means for controlling the same, reading means and reading control means for controlling the same, And mode control means for controlling the timing of reading and recording operations and controlling the copying operation,
A speed switching means for changing the timing of mode control according to the copy speed is provided, and in the recording control means,
The strobe data for energizing the recording head is stored according to the speed to control the heat generation according to the speed, and at the time of copying at the standard speed, the sensor is scanned N times (N is an integer of 2 or more) in one line, One data is discarded and the other data is validated and sent to the recording head. On the other hand, at the time of high-speed copying, the sub-scanning speed is increased by N times, but 1 in 1 line.
The sensor is scanned once so that the data is always valid and sent to the recording head to perform the copy operation.

In order to achieve the second object, as a second means, the A / D converter for the sensor output of the above means and the A / D converter for the thermistor output of the recording head are shared, and A switch for switching between the sensor output and the thermistor output is provided in front of the A / D converter, and the switch is switched by the mode control means. When copying at a standard speed, the sensor is scanned N times in one line, and one of the During scanning, the temperature data output by the thermistor is sent to the recording control means, the reading control means discards the data, validates the other data, and sends it to the recording head. On the other hand, at the time of high-speed copying, the sub-scanning speed is increased by N times, but the sensor is scanned once in one line to make the data always valid and sent to the recording head, but n lines (n is 2 lines or more, recording distance is Once every 1 cm to 10 cm), the switch is switched to the thermistor to read the temperature data into the recording control means, and in the reading means, the data read in the temperature reading line is the data read in the previous line. And so on (previous value interpolation), the copy operation is performed.

[0021]

According to the first means, in the reading of the copying operation, the sensor is read in 1 / N time of one line at the standard speed, and the sensor is read in one line time at the N times high speed operation. Therefore, the sensor exposure times of both sensors are constant, and it is possible to always obtain the same sensor output regardless of the difference in copy speed in the reading means using the same light source. Further, in recording, since energy corresponding to the difference in speed can be applied to the recording head, sufficient color development can be obtained at either the standard speed or N times speed.
An image copying apparatus having a double speed mode can be obtained.

In the second means, when reading the sensor in the reading of the copy operation, the reading means using the same light source has the same operation as the first means, regardless of the difference in copy speed. It is possible to obtain the same sensor output. Also, in recording,
Similarly, sufficient color development can be obtained at both standard speed and N times speed, and an image copying apparatus having a standard speed and N times speed mode can be obtained as a copy operation. The difference between the first means and the second means is that
The point is that the copy image quality may be impaired.

(1) Since the thermistor temperature is read every n lines, it is not possible to follow the temperature rise depending on the data to be recorded. (2) Since the line density in the sub-scanning direction is doubled once every n lines, the recording quality deteriorates.

However, for example, 200 dpi (Dot Per In
In the case of the ch) image copying apparatus, (1) the temperature rise of the recording head is at most 0.2 to 0.5 ° C./cm when all black dots are printed, and the operating temperature range of the normal apparatus is 6 bit A at (5-60 ° C)
The temperature resolution becomes about 1 ° C. by the / D conversion, which is almost the same as detecting and controlling the temperature of each line. (2) The width of one line in the sub-scanning direction is about 130 μm, and it is difficult to discriminate even if only one line of several cm has a line of 260 μm. That is, the experimental result was obtained, and it was confirmed that there is no practical problem.

[0025]

DESCRIPTION OF THE PREFERRED EMBODIMENTS FIG. 1 shows the structure of an image copying apparatus as an embodiment of the present invention. In the present embodiment, the speed of high-speed copying is set to twice the standard speed in order to make the explanation easy to understand.
I will explain.

As shown in FIG. 1, the image copying apparatus of this embodiment includes a controller 101 for controlling the entire apparatus,
A bus 102 such as a system bus and a data bus, an operation panel 103 for operating the image copying apparatus, and a document 2
Reading means 211 for reading the above information, reading control means 201 for controlling the reading means 211 to perform a reading operation, A / D converter 231 for converting the image output read by the reading means 211 into digital data,
A signal processing means 221 for simply converting the digital data into a binary image by a certain threshold level, or for expressing a halftone by a binary image by a dither method or an error diffusion method, and a thermal recording medium using thermal paper or thermal transfer ink. The recording means 311 for recording an image on the recording paper 3 according to the above, and a thermistor (not shown) provided on the recording head (not shown) in the recording means 311 to detect the substrate temperature of the recording head.
A / D converter 331 for converting the head temperature output 3130 into digital data, recording control means 301 for optimally controlling the recording means 311 by the head temperature output to perform the recording operation, and recording for storing image data to be recorded. The buffer 321 and the mode control means 401 for controlling the reading control means 201 and the recording control means 301 according to the operation mode instructed by the operation panel 103, and the timing of the mode control means 401 according to the copy operation speed instructed by the operation panel 103. And a speed switching unit 411 that determines

As described above, the image copying apparatus of this embodiment is roughly divided into reading means, recording means, and mode control means. First, individual explanations will be given, and then the entire explanation will be given.

The reading means will be described. FIG. 2 shows the configuration of the reading means 211 in the embodiment of FIG.

The reading means 211 includes a roller driving means 212 including a step motor (not shown) which is a driving source and a gear train (not shown) which is a driving force transmitting means, and a light source 21.
6 and the sensor section 217 composed of the photoelectric conversion element,
Sensor 215 for reading the image of the image in the main scanning direction
And a roller 213 that presses the reading sensor 215 and conveys the document 2 in the sub-scanning direction, and a document position detecting unit 214 that is installed upstream of the reading unit 215 and detects passage of the document 2. It

The reading control means 201 outputs a motor driving pulse 20131 to the roller driving means 212, and outputs a sensor driving pulse 2151 to the reading sensor 215. The reading sensor 215 outputs the read image signal 2170 to the A / D converter 231, and the image signal 217 converted into a digital signal by the A / D converter 231.
1 is output to the signal processing unit 221. Further, the output 2140 of the document position detecting means 214 is output to the controller 101 via the bus 102.

FIG. 3 shows the configuration of the read control means 201 and the signal processing means 221 in the embodiment of FIG.

The reading control means 201 is composed of a motor drive waveform generation means 2012, a motor drive circuit 2013, and a sensor drive waveform generation circuit 2014.
The signal processing unit 221 is the image signal transfer control unit 2213.
And a binarization circuit 2212. In the reading control means 201, the motor drive waveform generation means 20 outputs the line start pulse 2120 output from the reading system scanning timing generation means 4021 of the mode control means 401.
12 and inputs the motor drive pulse 20121 generated by the motor drive waveform generation means 2012 to the motor drive circuit 2
The pressure is increased by 013 and is output as a motor drive pulse 20131 to the step motor 2121 of the roller drive means 212, and the roller 213 is rotated via the gear train 2122, so that the document 2 is conveyed in the sub-scanning direction. Also,
The main scan pulse 2150 output from the reading system scan timing generation means 4021 of the mode control means 401 is input to the sensor drive waveform generation circuit 2014, and the sensor drive signal 2 is input.
151 is generated and the reading sensor 215 is driven. As a result, the reading sensor 215 reads the image on the document 2 in the main scanning direction each time the sensor drive signal 2151 is input. In the signal processing unit 221, the image signal transfer control unit 2213 inputs the main scanning pulse 2150 and the selection signal 2160 output from the reading system scanning timing generation unit 4021 of the mode control unit 401, and the binarization circuit 2
By controlling 212, the binarization circuit 2212 selects the A / D converted image signal 2171 at a predetermined timing, and the image signal 2171 is converted into 2 by the dither or error diffusion processing.
The image data 217 is converted to value data and is transferred to the bus 102.
It is output as 2, and is sequentially accumulated in the recording buffer 321.

FIG. 4 shows the timing of the reading operation in the embodiment of FIG. When the output of the document position detection means 214 is turned on and it is detected that the document 2 is set inside the reading means 211, the controller 101 causes the operation mode setting means (not shown) of the mode control means 401.
The operation mode setting means receives the copy operation according to the operation content of the operation panel 103, and outputs the copy instruction 1011 to the reading system scanning timing generation means 4021 of the mode control means 401.

In the reading means 221, the light source 216 of the reading sensor 215 is turned on, and the sensor section 217 accumulates light. When the document 2 passes over the reading sensor 215 and starts reading, the reading system scanning timing generation means 4021 outputs a line start pulse 2120 for each sub-scanning of one line, and the motor drive circuit 2013.
Generates a motor drive pulse 20131, and the roller 213
To rotate. Since a slight delay occurs due to the backlash of the gear or the twist of the shaft from the time when the original 2 is actually moved after the motor 2121 is driven, the reading system scanning timing generation means 4021 slightly changes the line start pulse 2120. Delayed, main scan pulse 2150
Is generated at a half cycle of one line, and the sensor drive signal 2
By outputting 151 in synchronization with the main scanning pulse 2150, the reading sensor 215 performs scanning twice in one line and outputs the image signal 2171. At this time, the selection signal 2160 is read and one of the two times is valid and the other one is invalid, so that the image signal 2172 output from the binarization circuit 2212 can be once per line. Therefore, the image on the original 2 can be read.

Next, the recording means will be described.
FIG. 5 shows the configuration of the recording means 311 in the embodiment of FIG.

The recording means 311 is a roller driving means 3 comprising a step motor (not shown) and a gear train (not shown).
15 and a recording head 312 of a line head for recording in the main scanning direction by heating the heating resistor array.
A roller 314 which conveys the recording paper 3 in the sub-scanning direction such that the recording paper 3 is pressed onto the recording head 312 and heat is applied to the recording head 312 so as to record on the paper via a thermal paper or an ink ribbon. The thermistor 313 is provided on the substrate or the heat sink of the recording head 312, detects the head temperature, and outputs a head temperature signal 3130.

The recording control means 301 is the roller driving means 3
15, the motor drive pulse 30131 is output to 15, the recording strobes 3121 and 3122 are output to the recording means 311, and the head temperature signal 3 output from the thermistor 313.
130 is input in a format converted into a digital signal by the A / D converter 331. Image data 217 to be recorded
The recording buffer 321 storing 2 outputs the image data 3017 in the main scanning direction for one line to be recorded to the recording head 312 of the recording unit 311.

FIG. 6 shows the construction of the recording control means 301 in the embodiment of FIG. The recording control unit 301 includes a motor drive waveform generation unit 3012 and a motor drive circuit 3013.
And a recording head strobe waveform generation circuit 3014. In the recording control means 301, the line start pulse 3150 output from the recording scan timing generation means 3160 of the mode control means 401 is input to the motor drive waveform generation means 3012, and the motor drive pulse generated in the motor drive waveform generation means 3012. 30121 is boosted by the motor drive circuit 3013 and transmitted as a motor drive pulse 30131 to the step motor 3151 of the roller drive means 315, and the roller 314 is rotated through the gear train 3152, so that the recording paper 3 is moved in the sub-scanning direction. Transport. Further, the main scanning pulse 3 output from the recording scanning timing generating means 4031 of the mode control means 401.
120 and the speed selection signal 4012 output from the operation mode setting means (not shown) are input to the recording head strobe waveform generation circuit 3014, the recording strobes 3121 and 3122 are output to the recording head 312, and the recording head 312 is driven. Each time, an image is recorded on the recording paper 3 in the main scanning direction at a predetermined speed. The print buffer 312 receives the main scan pulse 3120 output from the print scan timing generation means 4031 of the mode control means 401 and the selection signal 3160, and outputs the image data 3017 to be output to the print head 312 from the separately input image data 2172. select.

FIG. 7 shows the timing of the recording operation in the embodiment of FIG. The recording paper 3 is set inside the recording means 311 in advance. Controller 101
Outputs an operation start command to the operation mode setting means (not shown) of the mode control means 401, and the operation mode setting means
A copy operation is accepted according to the operation content of the operation panel 103, and a copy command 1011 is output to the recording scan timing generation means 4031 of the mode control means 401.

In the recording means 311, when the recording operation is started, the image data 3017 of the original 2 which has already been read by the reading means 211 and stored in the recording buffer 321 is input, and the recording scanning timing generating means 4031 outputs one line. A line start pulse 3150 is output for each sub-scan of the motor drive circuit 3013.
31 is generated, and the roller 314 is rotated. Motor 31
From the time when 51 is driven until the recording paper 3 actually starts moving, due to gear backlash, shaft twist, etc.
Due to a slight delay, the line start pulse 31
Recording scan timing generating means 403, slightly delayed from 50
1 generates the main scanning pulse 3120 for each line,
By inputting the recording strobes 3121 and 3122 synchronized with this to the recording head 312, an image in the main scanning direction can be recorded on the recording paper 3, and by repeating this, the image is recorded.

In the above description, the strobes 3121 and 3122 applied to the recording head 312 are divided into two.
Depending on the structure of the recording head 312 and the capacity of the recording power supply, the number of divisions is the same whether it is energized collectively or divided into four, and is effective. In this embodiment, the selection signal 3160 is always valid, and the image data 3017 is selected in each sub-scan.

FIG. 8 shows an outline of strobe data stored in the recording head strobe waveform generation circuit 3014 of FIG. Recording head strobe waveform generation circuit 3
In 014, by the input speed selection signal 4012,
It has a standard speed and a strobe data string for double-speed recording. Depending on the head temperature at the time of recording, the lower head temperature has a longer strobe pulse width, and the higher head temperature has a shorter strobe width. There is. Also,
If the head temperature is the same, the strobe width at double speed recording is shorter than the strobe width at standard speed. Further, each strobe width T needs to satisfy the condition of T ≦ (sub-scanning time of one line / the number of strobe divisions). When the standard speed is 10 ms / line and the number of strobe divisions is 2,
The strobe width at standard speed is 5 ms or less, and the strobe width at double speed is 2.5 ms or less.

FIG. 9 shows the configuration of the mode control means 401 and the speed switching means 411 in the embodiment of FIG.

The mode control means 401 includes a recording system scanning timing means 4031 which controls the recording operation timing,
A reading system scanning timing unit 4021 and an operation mode setting unit 4011 that control the reading operation timing.
It consists of and. The speed switching unit 411 includes a speed selection unit 4111 and a reference clock generation circuit 4112.
It consists of and.

The operation mode setting means 4011 inputs the operation start command 1010 from the controller 101, the operation mode input 1031 and the speed designation 1032 by the operation panel 103, and the recording system scanning timing means 403.
1 and the scanning command for scanning the scanning system 4021, and the speed selection signal 4012 is output to the recording head strobe waveform generating means 3014. The reference clock generation circuit 4112 converts the speed designated by the speed designation 1032 by the input of the operation panel 103 into the clock frequency division number n by the speed selection means 4111,
By inputting this, the reference clock is frequency-divided by n to be used as a reference clock for recording and reading operations, and output to the recording system scanning timing means 4031 and the reading system scanning timing means 4021. For example, n =
If n = 3, the operation becomes double speed, and n = 2.
Then, a triple speed operation becomes possible.

The recording system scanning timing means 4031 outputs the line start pulse 3150 and the main scanning pulse 3120 to the recording control means 301 and the selection signal 3160 to the recording buffer 321 by the above input. The reading system scanning timing means 4021 is
A line start pulse 212 is sent to the reading control means 201.
0 and the main scanning pulse 2150 are output, and the signal processing means 2 is output.
The selection signal 2160 is output to 21.

The operation will be described below. In the present embodiment, the reading unit 211 and the recording unit 311 are controlled to perform the copy operation. As the timing of the copy operation, FIG. 10 shows the timing of the copy operation at the standard speed in the present embodiment.

The reading operation is basically based on the timing shown in FIG. 4 and the recording operation is based on the timing shown in FIG. 7. However, the reading and recording are different in the lines for processing the image data by the same main scanning. is there.

In the figure, the line numbers N-2 to N + 2 of the copy operation managed by the mode control means 401 are shown. In the copy operation, the reading operation precedes the recording operation, as shown below. The reading operation synchronized with the line start pulse 2120 at the line number N-2 is performed twice in one line, one of which is invalidated by the selection signal 2160, and the other one is valid, but the reading is performed. The image signal 2170 (image signal 2171, image data 2172) is read by the sensor 215 in synchronization with the main scanning pulse 2150 of the (N-1) th line because of a time delay. Furthermore, the image data 2172 is recorded in the recording head 31.
The recording strobe 3121 synchronized with the main scanning pulse 3120 of the Nth line is transferred to the recording strobe 3121.
3122.

Further, when the image signal 2171 for several lines is arithmetically processed by the binarization circuit 2212 to obtain high-quality image data 2172, the reading line number and the recording line number are 1 or more lines shown in the figure. Will increase.

FIG. 11 shows the timing of the copy operation at the high speed in the embodiment of FIG. It should be noted that, in the present embodiment, the case in which the high speed copying is twice the standard speed is shown. Further, the time axis shown in FIG. 11 is shown such that the same time is twice as long as the length in the time axis direction as compared with the time axis shown in FIG.

The line numbers N-2 to N + 2 of the copy operation managed by the mode control means 401 are shown. In the copy operation, the read operation precedes the recording operation, similarly to the standard speed copy operation shown in FIG. The relationship between the line number, the reading line number, and the recording line number is shown in FIG.
This is similar to the standard speed copying operation shown in.

The timing of the recording operation is shown in FIG.
Although it seems to be similar when compared with, the time axis shown in FIG. 11 is shown to be twice as long as the time axis shown in FIG. 10, as described above. Therefore, in reality, the scanning time in the recording operation is as shown in FIG.
It is half that of the standard speed recording operation shown in.

On the other hand, the timing of the reading operation is as described below. Reading operation (main scanning) in synchronization with the line start pulse (the cycle is 1/2 of the standard speed shown in FIG. 10) 2120 at line number N-2
Is performed once in one line, and the selection signal 2160 is
It is always valid. An image signal 2170 (image signal 2171, image data 217) from the reading sensor 215
The reading of 2) is performed in synchronization with the main scanning pulse 2150 of the (N-1) th line because of the time delay. Furthermore,
Transferring the image data 2172 to the recording head 312 to perform the recording operation is performed by the main scanning pulse 3120 of the Nth line.
According to the recording strobes 3121 and 3122 synchronized with.

Here, the scanning time for one reading is as shown in FIG.
It is the same as the reading scan time for one reading in the case of the standard speed shown in 0 (that is, in the case of the double speed in FIG.
The period of the main scanning pulse 2150 is the same as the case of the standard speed shown in FIG. Therefore, the exposure time of the reading sensor unit 217 in one scan in the reading operation is as shown in FIG.
The case of the standard speed shown in FIG. 11 and the case of the double speed in FIG. Therefore, the image can be read with a constant quality regardless of the copy operation speed.

In this embodiment, according to the above timing,
In the copying operation at the standard speed, the reading operation is performed twice in one line, the reading operation is made valid only once, and the valid data is recorded. On the other hand, in the copy operation at double speed, the sub-scanning time is halved (double the speed) of the standard speed, and only the main scanning time for reading is the same as the standard speed.
By performing the reading operation once in one line and performing the recording, it is possible to provide the image copying apparatus having two kinds of copying operation speeds of the standard speed and the double speed.

In the above embodiment, the number n of readings in one line at the standard speed is n = 2, and the speed in the high speed mode is the double speed of the standard speed. However, the same operation is performed when n = 3, 4, ... High-speed copy operation of 3 or 4 times speed is possible depending on the timing, which is effective.

FIG. 12 shows the configuration of an image copying apparatus as another embodiment of the present invention. In the present embodiment, the A / D converters 221 and 33 that respectively A / D-convert the image signal 2170 and the head temperature signal 3130 in the embodiment of FIG.
1 is replaced with a common A / D converter 31, and the image signal 2
170 and a head temperature signal 3130 are input, and a switch 32 for selecting an output to the A / D converter 31 by a switching signal 4013 is provided in the preceding stage of the A / D converter 31.
The output of the A / D converter 31 is output to the signal processing unit 221 and the recording control unit 301.

FIG. 13 shows the configuration of the mode control means 402 and the speed switching means 411 in the embodiment of FIG.

The mode control means 402 is a recording system scanning timing means 4031 for controlling the recording operation timing,
A reading system scanning timing unit 4021 and an operation mode setting unit 4011 that control the reading operation timing.
And a switching signal generating means 4 for switching the switch 32.
041. The speed switching means 411
Speed selection means 4111 and reference clock generation circuit 411
2 and.

The operation mode setting means 4011 inputs the operation start command 1010 from the controller 101, the operation mode input 1031 and the speed designation 1032 by the operation panel 103, and the recording system scanning timing means 403.
1 and the reading system scan timing means 4021, the copy command 1011 is output, the recording head strobe waveform generation means 3014 outputs a speed selection signal 4012, and the switching signal generation means 4041 outputs a timing signal 4042. The reference clock generation circuit 4112 converts the speed designated by the speed designation 1032 by the input of the operation panel 103 into the clock frequency division number n by the speed selection means 4111, and inputs this to divide the reference clock by n. Then, it is used as a reference clock for recording and reading operations, and is output to the recording system scanning timing means 4031 and the reading system scanning timing means 4021. For example, if n = 6 in the standard time, a double speed operation is possible with n = 3, and a triple speed operation is possible with n = 2.

The recording system scanning timing means 4031 outputs the line start pulse 3150 and the main scanning pulse 3120 to the recording control means 301 and the selection signal 3160 to the recording buffer 321 by the above input. The reading system scanning timing means 4021 is
A line start pulse 212 is sent to the reading control means 201.
0 and the main scanning pulse 2150 are output, and the signal processing means 2 is output.
The selection signal 2160 is output to 21. The switching signal generating means 4041 sends a switching signal 4013 to the switch 32.
Is output.

The operation will be described below. In this embodiment also, the reading unit 211 and the recording unit 311 are controlled to perform the copy operation. As the timing of the copy operation, FIG. 14 shows the timing of the copy operation at the standard speed in this embodiment.

The reading operation is based on the timing shown in FIG. 4 and the recording operation is based on the timing shown in FIG. 7. In reading and recording, the same main scanning image data is processed as in the embodiment of FIG. The lines to do are different. However, in the switch 32, the image signal 2170
The feature is that the number of processes for switching between the head temperature signal 3130 and the head temperature signal 3130 and detecting the signals at appropriate timings is increasing.

In the figure, the line numbers N-2 to N + 2 of the copy operation managed by the mode control means 401 are shown. In the copy operation, the reading operation precedes the recording operation, as shown below. The reading operation synchronized with the line start pulse 2120 at the line number N-2 is performed twice in one line, one of which is invalidated by the selection signal 2160, and the other one is valid, but the reading is performed. The image signal 2170 (image signal 2171, image data 2172) is read by the sensor 215 in synchronization with the main scanning pulse 2150 of the (N-1) th line because of a time delay. By setting the switching signal 4013 on the image image signal 2170 side during the reading period of the valid image signal 2170 and on the head temperature signal 3130 side during the invalid reading scanning period, the reading becomes invalid. The head temperature signal 3130 can be read during the scanning period. Further, the transfer of the image data 2172 to the recording head 312 and the recording operation are performed by the recording strobes 3121 and 3122 synchronized with the main scanning pulse 3120 of the Nth line. At this time, the strobe data in the recording head strobe waveform generation circuit 3014 shown in FIG. 8 is selected according to the detected head temperature signal 3130, and proper recording can be performed for each line with a strobe width corresponding to the head temperature. It will be possible.

FIG. 15 shows the timing of the copy operation at the high speed in the embodiment of FIG. It should be noted that, in the present embodiment, the case in which the high speed copying is twice the standard speed is shown. Further, the time axis shown in FIG. 15 is shown such that the same time is twice as long as the length in the time axis direction as compared with the time axis shown in FIG.

The line numbers N-2 to N + 2 of the copy operation managed by the mode control means 401 are shown. In the copy operation, the read operation precedes the recording operation, similarly to the standard speed copy operation shown in FIG. The relationship between the line number, the reading line number, and the recording line number is shown in FIG.
This is similar to the standard speed copying operation shown in.

The timing of the recording operation is shown in FIG.
Although it seems to be similar when compared with, the time axis shown in FIG. 15 is shown to be twice as long as the same time as the time axis shown in FIG. 14, as described above. Therefore, in reality, the scanning time in the recording operation is as shown in FIG.
It is half that of the standard speed recording operation shown in. Further, when the image signal 2170 and the head temperature signal 3130 are switched by the switch 32, only the image reading scanning can be performed in the sub-scanning time of one line, so the head temperature signal 313 is set for each N lines (N is an integer of 2 or more).
A feature is that a sub-scanning line for reading only 0 is provided, and the recording data in the main sub-scanning line is the data of the previous line (N-1) continuously recorded and interpolated.

The operation will be described below. Line number N-
The reading operation (main scanning) in synchronization with the line start pulse (the cycle is 1/2 at the standard speed shown in FIG. 10) 2120 in 2 is performed once in one line, and the selection signal 2160 is It is always valid. Reading sensor 21
The reading of the image signal 2170 (image signal 2171, image data 2172) according to No. 5 is N because there is a time delay.
It is performed in synchronization with the main scanning pulse 2150 of the -1st line. Further, the image data 2172 is transferred to the recording head 312 and the recording operation is performed by the recording strobes 3121 and 312 synchronized with the main scanning pulse 3120 of the Nth line.
According to 2.

On the N + 1th line, the switching signal is set on the side of the head temperature signal 3130 and the selection signal 216 is set.
The head temperature signal 3130 is read by setting 0 as invalid. At this time, N which is the read line scanned and read
Since the image data 2170 of the line becomes invalid and the image signal 2170 for one line cannot be obtained, the image signal 2170 of the (N-1) th line, which is the read line read in the previous line, is used again to record the N line of the recording line. Recorded data for the eyes. When reading the head temperature signal 3130,
In the recording head strobe waveform generation circuit 3014, the strobe width is reset according to the head temperature signal 3130, and thereafter, the head temperature signal 3 is reset at the 2N + 1th line.
Recording is performed with the same strobe width until 130 is read.

Here, the scanning time for one reading is as shown in FIG.
It is the same as the reading scanning time for one reading in the case of the standard speed shown in FIG.
The period of the main scanning pulse 2150 is the same as the case of the standard speed shown in FIG. Therefore, the exposure time of the reading sensor unit 217 in one scan in the reading operation is as shown in FIG.
The same results are obtained in the case of the standard speed shown in FIG. Therefore, FIG.
Similar to the embodiment described above, the image can be read with a constant quality regardless of the copy operation speed.

In this embodiment, according to the above timing,
In the copy operation at the standard speed, the reading operation is performed twice in one line, the valid data is recorded only once, the valid data is recorded, and the head temperature is read in the other invalid recording, and the temperature is controlled for each line. It can be performed. On the other hand, in the copy operation at the double speed, the sub-scanning time is halved (double the speed) of the standard speed, and only the main scanning time of reading is the same as the standard speed, and the reading operation is performed once in one line. Furthermore, the head temperature is read for each N lines, the print data is interpolated with the previous value, and the recording is performed according to the head temperature read for each N line. It is possible to provide an image copying apparatus having the above.

Also in this embodiment, the number of readings n in one line at the standard speed is n = 2, and the speed in the high speed mode is double the standard speed. However, if n = 3, 4, ...
High-speed copy operation of 3 or 4 times speed is possible with the same operation timing, which is effective. Further, in this embodiment,
The characteristic feature is that when recording at double speed, only one line per N lines is recorded at half the linear density in the case of standard speed. However, by taking a large N, the same recording quality as in standard speed can be obtained. Obtained and effective. Further, since the A / D converter is shared, the device can be realized at low cost.

[0074]

As described above, according to the present invention, (1) in the reading operation by the reading means, the same read image quality can be obtained in both the standard speed and the N times speed mode regardless of the operation speed. . (2) Also in the recording operation, it is possible to obtain recording quality with the influence of the operation speed suppressed to a minimum. As a result, it is possible to realize an image copying apparatus that can perform standard-speed and high-speed reading and recording operations and obtain high-quality copy results.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of an image copying apparatus as an embodiment of the present invention.

FIG. 2 is a block diagram showing a configuration of a reading unit 211 in the embodiment of FIG.

FIG. 3 is a read control unit 20 in the embodiment of FIG.
2 is a block diagram showing the configurations of signal processing means 221 and signal processing means 221. FIG.

FIG. 4 is a timing chart showing the timing of the reading operation in the embodiment of FIG.

5 is a block diagram showing a configuration of a recording unit 311 in the embodiment of FIG.

6 is a block diagram showing a configuration of a recording control unit 301 in the embodiment of FIG.

FIG. 7 is a timing chart showing the timing of the recording operation in the embodiment of FIG.

FIG. 8 is a recording head strobe waveform generation circuit 30 of FIG.
14 is a characteristic diagram showing an outline of strobe data stored inside 14. FIG.

9 is a block diagram showing a configuration of a mode control unit 401 and a speed switching unit 411 in the embodiment of FIG.

10 is a timing chart showing the timing of the copy operation at the standard speed in the embodiment of FIG.

11 is a timing chart showing the timing of a copy operation at a high speed in the embodiment of FIG.

FIG. 12 is a block diagram showing a configuration of an image copying apparatus as another embodiment of the present invention.

13 is a mode control means 40 in the embodiment of FIG.
2 is a block diagram showing the configurations of 2 and speed switching means 411. FIG.

14 is a timing chart showing the timing of a copy operation at the standard speed in the embodiment of FIG.

15 is a timing chart showing the timing of a copy operation at a high speed in the embodiment of FIG.

[Explanation of symbols]

101 ... Controller, 103 ... Operation panel, 201 ...
Read control means, 211 ... Read means, 221, ... Read control means, 311 ... Recording means, 301 ... Recording control means, 321 ... Recording buffer, 401 ... Mode control means, 411 ... Speed switching means, 3014 ... Recording head strobe waveform generation Means, 4012 ... speed selection signal, 4
031: recording system scanning timing means, 4021: reading system scanning timing means, 4041 ... switching signal generating means, 4112 ... reference clock generating circuit.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Toyota Honda, 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa, Ltd. Inside the Visual Media Research Laboratory, Hitachi, Ltd. (72) Inventor Mikio Shiraishi 292 Yoshida-cho, Totsuka-ku, Yokohama-shi, Kanagawa Address Company, Hitachi, Ltd. Visual Media Research Laboratory (72) Inventor Yasuyuki Kojima 1410 Inada, Katsuta City, Ibaraki Prefecture Hitachi, Ltd. Information & Video Media Division (72) Inventor Toshio Yazoe 1410 Inada, Katsuta City, Ibaraki Prefecture Hitachi, Ltd. Information & Video Media Division (72) Inventor Hiroshi Minota 1410 Inada, Katsuta City, Ibaraki Prefecture Hitachi, Ltd. Information & Video Media Division (72) Inventor Akira Shimizu 1410 Inada, Katsuta City, Ibaraki Hitachi Information Technology Co., Ltd. Inside the Media Division

Claims (2)

[Claims] 1. A reading unit that outputs an image described on a document or the like as a read image signal, a reading control unit that controls the reading unit, and an image obtained by performing signal processing on the image signal output from the reading unit. An image is recorded on a recording paper based on the signal processing unit that outputs as data, the image data output from the signal processing unit, and the recording buffer that outputs the image data once, and the image data output from the recording buffer. Recording means, recording control means for controlling the recording means, and mode control means for controlling the reading control means, the signal processing means, and the recording control means in accordance with a selected mode from the first and second modes. In the image copying apparatus including the following, the mode control means, when the first mode is selected, at the time of reading, By controlling the sampling control means and the signal processing means, the reading means performs the main scanning N times (N is an integer of 2 or more) during one sub-scanning by the control by the reading control means. The image is read and output as an image signal, and the signal processing unit selects and outputs image data for one main scanning from the image data obtained by the N main scannings. At the time of recording, the recording control means is controlled so that the recording means controls the recording control means during one sub-scanning based on the image data for one main scanning. An image is recorded by main scanning, and when the second mode is selected, the sub-scanning speed is set to N times that in the first mode, and when reading,
The reading control means is controlled so that the reading means controls the reading control means to perform one main scan during one sub-scan to read an image, and to output the image signal as an image signal. At the time of recording, the recording control unit is controlled so that the recording unit controls the recording control unit to perform 1 sub-scanning based on the image data obtained by the 1 main scanning. An image copying apparatus characterized in that an image is recorded by performing main scanning once. 2. A reading unit for outputting an image described on a document or the like as a read image signal, a reading control unit for controlling the reading unit, and a temperature of a thermal recording head provided in the recording unit, A recording head temperature detecting means for outputting the detection result as a head temperature signal, an image signal output from the reading means, and a head temperature signal output from the recording head temperature detecting means are input, and either one is selected. And a signal switching means for outputting the signal, an analog / digital converting means for performing analog / digital conversion of the signal output from the signal switching means, and outputting the analog / digital conversion means when the image signal is selected by the signal switching means. A signal that receives the image signal output from the digital conversion means, performs signal processing, and outputs it as image data. Signal processing means, a recording buffer that temporarily stores the image data output from the signal processing means, and then outputs the image data, and an image is recorded on the recording paper by the thermal recording head based on the image data output from the recording buffer. The recording means and the head temperature signal output from the analog / digital converting means when the head temperature signal is selected by the signal switching means are input, and the recording means is controlled based on the head temperature signal. Recording control means for controlling the reading control means, the signal switching means, the signal processing means, and the mode control means for controlling the recording control means according to the selected mode among the first and second modes. In the image copying apparatus including the above, the mode control means, when the first mode is selected, at the time of reading, By controlling the sampling control means, the signal switching means, and the signal processing means, the reading means controls N times (N is an integer of 2 or more) in the main scanning operation during one sub-scanning. Scanning is performed to read an image and output as an image signal, and the signal switching unit selects and outputs the image signal from the reading unit for one main scanning among the N main scannings. However, for other main scans, the head temperature signal from the recording head temperature detecting means is selected and output without selecting the image signal, and the signal processing means outputs the head / temperature signal from the digital / analog converting means. The image signal is selected from the recorded signals and is output as image data, and at the time of recording, the recording control means is controlled so that the recording device Under the control of the recording control means, during one sub-scan, an image is recorded by one main scan based on the image data for one main scan, and the second mode is selected. In this case, the sub-scanning speed is set to N times that in the first mode, and at the time of reading,
The reading control means is controlled so that the reading means controls the reading control means to perform one main scan during one sub-scan to read an image, and to output the image signal as an image signal. At the time of recording, the recording control unit is controlled so that the recording unit controls the recording control unit to perform 1 sub-scanning based on the image data obtained by the 1 main scanning. An image copying apparatus characterized in that an image is recorded by performing main scanning once.