JPH06164860A - Facsimile equipment - Google Patents

Abstract

PURPOSE:To prevent production of an uneven recording pitch by recording data while a recording paper step feed of a scanning line is more increased than an original step number when a waiting period of time is long and driving the recording step in opposite direction by an excessively inserted step number. CONSTITUTION:When a synchronizing signal LSNC for each succeeding at every 2/Nmm arrives after a timer means 55 finishes the measurement because of a long waiting period of time, the step feed of recording paper is started in advance by a time tmsec in excess of n-steps with respect to a 1st scanning line. Thus, the response of recording for a 1st scanning line is improved. The recording paper is fed in 2m-steps in the 2nd scanning line and the motor is driven in the opposite direction by n-steps quickly afterward. The rotating position of the rotor of the motor is slower than the changeover of an exciting phase regardless of reverse direction and no reverse rotation is caused. Thus, the recording paper is sent in (4m+62) steps in the 1st and 2nd scanning lines and the recording paper is sent in 2/Nmm pitch while the 1st and 2nd scanning lines are recorded.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention performs sub-scan feed of recording paper by using a step motor, and the line image information read at a sub-scan pitch of 2 / N mm on the transmitting side is 1 / N on the receiving side.
2 across the first and second lines set to mm pitch
The present invention relates to a facsimile device that continuously reproduces recording paper.

[0002]

2. Description of the Related Art In a facsimile machine, image information of an original read by a transmitting side is encoded and transmitted for each scanning line, but the information amount of each scanning line changes variously depending on the pattern of the transmitting original, and one scanning is performed. The transmission time of the wire varies greatly. The sub-scan feed of the recording paper on the receiving side also largely changes, and a step motor has been conventionally used to perform an intermittent / variable speed operation. As a recording method, a method in which a thermal line head in which heating elements corresponding to the number of scanning line pixels are arranged is used to reproduce on thermal paper is widely used. The recording paper is conveyed by sandwiching the thermal recording paper between the rubber platen roller and the thermal head and rotating the rollers, and the pressure of the thermal head is several kilograms to ensure close contact between the thermal head and the recording paper. Is set to. The rotation of the step motor is decelerated by a gear train, a timing belt, or the like, and the unit rotation angle of the step motor is designed to be a predetermined paper feed amount corresponding to the sub-scanning resolution. Even when there is no backlash in the transmission system, there is a delay in the response of the step motor itself, or the transmission of the step motor from the moment the drive of the step motor is started while the recording paper is stationary until the recording paper actually starts moving. Delay occurs due to system rigidity, roller rubber elasticity, friction load, and inertia load. This delay time is a few milliseconds. It takes 10 msec or more to complete the predetermined feeding. Recording paper feed and recording are performed in synchronization.

As is well known, in the Group 3 standard, the standard mode (3.85 lines / mm) and the high resolution mode (7.7 lines / m) are used.
m) 1 in most cases in high resolution mode
Since the transmission time of the scanning line is longer than the moving time of the recording paper, the movement of the recording paper for each scanning line can be recorded in the same period, and thus the pitch between the recorded pixels becomes equal.
In the case where the minimum transmission time is continuous, the recording paper is sent and recorded without stopping, so that it is possible to avoid a gap due to uneven pitch in the reproduced image.

In the apparatus of the recording mechanism which realizes the standard resolution by recording the high resolution two continuous scanning lines with the same information in the standard mode, the second step following the recording sheet step feed of the first scanning line and the recording start. The stepwise feeding and recording of the scanning line recording paper is started after ½ of the minimum transmission time has elapsed after the start of the first scanning line. Therefore, when the amount of information to be transmitted is large and the transmission time is long, after the recording of the previous scanning line is completed, the recording paper feed is stopped and waits until the recording information of the next scanning line is determined, and then the first and second lines. The recording paper step feed and recording are continuously performed. Since the movement of the recording paper is slow in response, for example, the minimum transmission time is 20
In the case of msec, the first scanning line starts recording paper step feed from the stopped state, while the second scanning line starts recording paper step feed while the recording paper is moving. The movements of the recording paper on the first and second scanning lines are different. As a result, the recording pitch between the first and second scanning lines becomes small, causing unevenness in the pitch of the reproduced image on the recording paper, which deteriorates the quality.
Further, when this waiting time becomes long, the recording paper is conveyed in a state in which the spring property existing in the drive system is distorted in response to the conveyance load, so the amount of distortion during the stop period is reduced and static friction and dynamic friction are reduced. The movement of the recording paper on the first line becomes dull due to the difference in the above, and the amount of movement during the recording period decreases, and the recording pitch unevenness increases.

As a conventional technique for improving such a problem,
There is a Japanese Patent Publication No. 63-36188 "Facsimile receiver".

[0006]

SUMMARY OF THE INVENTION It is an object of the present invention to provide an improved facsimile apparatus which corrects the information transmitted by improving the pitch unevenness when the waiting time is long in the standard mode. To do.

That is, when the waiting time is detected to be long and short, and the waiting time is long, the recording paper step feed of the first scanning line is activated and recorded in advance with the number of steps larger than the original number of steps, and The second scanning line is sent in a predetermined number of steps, and immediately thereafter, it is driven in the reverse direction by the number of extra steps inserted in the first scanning line to improve the movement of the recording paper, thereby preventing the occurrence of recording pitch unevenness. To do.

[0008]

In order to achieve the above object, first and second line image information read at a sub-scanning pitch of 2 / Nmm on the transmitting side is set to a 1 / Nmm pitch on the receiving side. In the facsimile machine that reproduces the recording paper continuously twice over 2 lines of 2, the step motor is set to 2
The first (m) is a 1 / Nmm pitch conveyance by step driving (m is a natural number), and responds to the synchronization signal every 2 / Nmm.
And recording paper feed step motor drive signal forming means for the second line, recording strobe signal forming means, and 2 / Nmm.
A preset Tsec that is at least the time for completing the recording of the first and second scanning lines in response to each synchronization signal.
And timer means for measuring.

[0009]

[Function] Based on the synchronization signal every 2 / Nmm, the following 2 /
When the synchronization signal for each Nmm arrives within the measuring time Tsec of the timer means, the motor is continuously driven through the first and second lines by 2m steps, and the first line is the first step and the second line is 2m + 1. When recording is started with a delay of a predetermined time from the step, and when the next synchronizing signal every 2 / Nmm arrives after the elapse of the measurement time Tsec of the timer means, the step of the first line is advanced by a preset time tmsec. Start the motor drive and move the first line to n + 2
It is sent in m steps, the second line is driven by 2m steps, and then quickly driven in the opposite direction by n steps, and the first line is delayed by a predetermined time from the (n + 1) th step and the second line is started from the (n + 2m + 1) th step, and recording is started.

When the next synchronization signal of every 2 / Nmm arrives before the timer means finishes the measurement due to the short waiting time, the recording paper step feed of the first and second scanning lines is made 2 m each.
Step by step, and from the start of feeding the recording paper step,
Recording is started after a predetermined time. Here, the reason why the recording is started after the start of driving the motor is to compensate for the delay of the movement of the recording paper and start the recording from the vicinity from the time when the recording paper starts to move on the first scanning line. Even in the second scanning line, the movement of the recording sheet is reflected with a similar delay from the time when the recording step feed is started, so that recording can be performed in a period in which the first and second scanning lines have similar movements of the recording sheet. Pitch unevenness does not occur.

When the waiting time is long and the next synchronizing signal of every 2 / Nmm arrives after the timer means finishes the measurement, the stepwise feeding of the recording paper is preceded by n steps for the first scanning line by tmsec. The start improves the recording paper response of the first scan line. In the second scan line,
The recording paper is fed in 2 m steps, and then the motor is immediately driven in the reverse direction by n steps. Even if the motor is driven in the reverse direction, the rotational position of the rotor of the motor is delayed with respect to the switching of the excitation phase, and the motor is driven in the reverse direction promptly, so that it does not mechanically rotate in the reverse direction. The number of steps n and the timing are selected so that at least the reverse rotation does not occur. As a result, the first and second scanning lines are sent in 4m + n steps, so that 2 / N can be obtained while recording the first and second scanning lines.
It can be improved so that mm-pitch recording paper can be fed. It is possible to prevent uneven recording pitch. Further, since the n steps are driven in the opposite direction, the 2 / Nmm pitch itself does not spread.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As an embodiment of the device of the present invention, the minimum transmission time of one scanning line is set according to the CCITT standard.
0 msec (20 msec in standard mode), sub-scanning line density 7.7
Books / mm (high resolution mode) 2048 pixels per scanning line
The facsimile machine will be described in detail.

FIG. 2 is a block diagram showing the structure of the receiving section. In FIG. 2, the facsimile signal transmitted from the transmission side device after being encoded is demodulated by the modem 1 and the signal processing unit 2 separates the image signal and the synchronizing signal of the scanning line into the memory 3. Is stored. The signal processing unit 2 calls the image data from the memory 3 for each scanning line, decodes the image data, transfers the image data to the thermal line head 4 by the write clock signal WCLK and the latch signal LACH, and
Synchronization signal LSNC and mode designation signal MOD for each scanning line
E, the reset signal RSET is output to the recording control unit 5, the recording control unit 5 generates the recording strobe signal STRB and outputs it to the thermal line head 4, and outputs the motor drive signal MDRV to the step motor drive circuit 6.

The step motor drive circuit 6 receives a drive signal M
The DRV is decoded to turn ON / OFF the power supply to the coil of the step motor 7. The rotation of the step motor 6 is decelerated by a gear train (not shown) and transmitted to the platen roller. The thermal recording paper is sandwiched between the platen roller and the thermal line head 4, and the recording paper is fed to reproduce the image data. The step motor is a PM type with a step angle of 7.5 degrees,
Four energizing coils are driven alternately by 1-2 phase excitation,
Repeatedly switching the excitation phase with step as one cycle 4
The reduction ratio and the platen roller diameter are set so that the recording paper feed amount is 7.7 lines / mm when the motor is rotated by 15 degrees. The thermal line head 4 includes a shift register and a latch corresponding to 2048 pixels, a transistor for energizing a heating resistor, and an AND gate provided between the transistor and the latch output.
The input is connected to the latch output and the other input is connected to the strobe signal for energizing the heating resistor and divided into four blocks consisting of a plurality of pixels. The strobe inputs of the same block are connected in common and four strobes are connected. The image data of 2048 pixels is reproduced by sequentially scanning. The time required to record 2048 pixels per scanning line is about 10
msec. Reference numeral 8 is a microprocessor that controls the modem 1 and the signal processing unit 2 in a centralized manner.

FIG. 1 is a block diagram showing a detailed configuration of the recording control unit 3, and when the waiting time is long in the standard mode, the recording paper is stepwise advanced by tmsec with respect to the next first scanning line by one step. In the second scanning line, the step motor 7 is moved so as to feed the 4-step recording paper and quickly drive the motor in the reverse direction by 1 step.
While driving, the recording operation is performed with a recording delay of a fixed time. FIG. 3 is a timing chart showing the operation in the standard mode of FIG.

In FIG. 1, reference numeral 50 denotes a time required for recording the synchronization signal LSNC output from the signal processing unit 2 (10 msec).
It is a delay circuit for delaying and operates only when the mode designation signal MODE designates the standard mode. Reference numeral 51a is an OR gate, and a pulse is inserted 10 msec after the synchronization signal LSNC and its delay signal are added.
The inserted delay signal is a synchronizing signal for the second scan line when writing twice in the standard mode. OR gate 51
The output of a is delayed by the delay circuit 52 for tmsec. The output signal a of the delay circuit 52 becomes the start signal of the step feed of the step motor 7 at the time of recording, and the step pulse generation circuit 54
Is input to the recording strobe signal generation circuit 53. The step pulse generation circuit 54 uses the signal a as a starting point for 2.5 msec.
Four step pulses b at intervals are generated and input to the OR gate circuit 51b. The strobe signal STRB generation circuit 53 generates four strobe signals STRB1 to STRB4 each delayed by a predetermined time from the signal a. (See Figure 3)
The strobe signals STRB1 to STRB4 are connected to the strobe inputs of the blocks 1 to 4 of the thermal line head 4, respectively. The heating resistor of the thermal head 4 is energized during the high level period of the strobe signal.

Reference numeral 55 is a timer composed of a re-triggerable mono-multi circuit which is triggered by a synchronizing signal LSNC, and operates only when the mode designating signal MODE designates the standard mode and stays at a high level for a certain period of time. Is output and is always set to a high level except in the standard mode. An edge pulse generation circuit 56 outputs one pulse d at the positive edge of the output signal c of the timer 55 and inputs it to the OR gate circuit 51b. Reference numeral 57 is a mono-multi circuit that is triggered by the positive edge of the output signal c of the timer 55, and outputs a signal that becomes high level for a period slightly shorter than (20 + t) msec, and is input to the edge pulse generation circuit 58 and the edge pulse generation circuit 58 The pulse e is output at the negative edge of the output signal of the mono-multi circuit 57. Reference numeral 59 is a 3-bit binary up / down counter. The output of the OR gate circuit 51b is connected to the up-count input, and the output of the edge pulse generation circuit 58 is connected to the down-count input. Reset signal RSET to be excited
Set by. The output code signal MDRV of the up / down counter 59 is decoded by the step motor drive circuit of FIG. 2 so that the motor coils are alternately energized for one-phase and two-phase energization to drive 1-2 excitation. The driving direction of the motor is the sub-scanning direction during the count-up, and the reverse direction during the count-down.

When the mode designating signal is not the standard mode, the delay circuit 50 and the timer 55 do not operate, so that the step feed and recording of the recording paper are performed in synchronization with the signal a obtained by delaying the synchronizing signal LSNC.

In the standard mode, when the time interval of the synchronizing signal LSNC for every 3.85 lines / mm is shorter than the high level period of the timer 55, the output of the timer 55 is high level, so the edge pulse generating circuit 56 The edge pulse generation circuit 58 also does not generate a pulse because it does not generate a pulse and the mono-multi circuit 57 is not triggered. Therefore O
The output pulse train of the R gate circuit 51b is only the output pulse of the step pulse generation circuit 54, and the up / down counter 59 only counts up.

In the standard mode, when the time interval of the synchronizing signal LSNC is longer than the high level period of the timer 5, the output c of the timer 55 is at the low level when the synchronizing signal LSNC arrives and is retriggered by the synchronizing signal LSNC. And outputs a positive edge, the edge pulse generation circuits 56 and 58 and the mono-multi circuit 57 operate and OR
A pulse is inserted into the output of the gate circuit 51b at the timing of the synchronization signal LSNC. Since the output pulse train of the step pulse generation circuit 54 is delayed by the delay circuit 52 from the synchronization signal LSNC, the step feed of the step motor is started earlier than the original step pulse train by the delay time tmsec of the delay circuit 52. This time t is determined in consideration of the response time of the recording paper, but it is a number.
It is a value of msec. A pulse is input to the down input of the up / down counter 59 by the mono-multi circuit 57 with a delay of approximately (20 + t) msec from the synchronization signal LSNC. This time point is the time point when 2.5 msec has elapsed after the completion of sending the step pulse of the second scanning line, and the mechanical response of the rotor of the step motor is delayed, so even if it is driven in the reverse rotation, It cannot be reversed. In addition, mono-multi circuit 5
The pulse width of 7 is set to be slightly shorter than (20 + t) msec, which means that the countdown pulse and the countup pulse interfere with each other when there is a long waiting time and the minimum transmission time is the next scan line. This is to avoid. Even in such a case, there is no particular problem for the same reason. The set time of the timer 55 is set to 50 msec. The start timing (recording delay time) of the strobe signal STRB1 is set to be near the time when the recording paper starts moving. The bottom line of FIG. 3 shows the excitation transition of the step motor in this embodiment, and represents the count value of the up / down counter 59. When the count value of the up / down counter 59 is an even number and one-phase excitation is an odd number, it is decoded by the drive circuit 6 so as to be two-phase excitation. Even if there is a count-up or count-down step, it remains in the 1-phase excitation state during the waiting time.

In the above embodiment, the delay circuits 50 and 52 are provided.
Step pulse generation circuit 54, strobe generation circuit 5
It is obvious that 3 can be easily realized by a counter, a decoder, a gate, a shift register and the like.

FIG. 4 shows the results of measuring the movement of the recording paper before and after the above-described embodiment. The 0 on the horizontal axis is the start point of the step motor feed, and is the recording sheet fed at a cycle of 300 msec. The rising characteristics of the recording paper are improved. It is obvious that the recording pitch unevenness can be reduced as a whole by enlarging the recording pitch of the first scanning line and the second scanning line.

The present invention is not limited to the above embodiment, and the response of the recording paper changes depending on the size of the load and the characteristics of the power transmission system, so the time t, the timer time, and the number of steps to be inserted are corresponding. It can be changed appropriately.

[0024]

As described above, according to the present invention, even if the waiting time is long, the response of the recording paper can be improved in the increase in the delay in rising, the recording pitch unevenness can be reduced, and the image quality of the received re-image can be improved. is there. Further, since the motor is driven by the 1-2 phase excitation, the noise of the device can be reduced, and since the 1 phase excitation is performed during the waiting time, the power consumption of the motor is small and the temperature rise is small.

[Brief description of drawings]

FIG. 1 is a block diagram showing an embodiment.

FIG. 2 is an overall configuration diagram showing an embodiment.

FIG. 3 is an operation timing chart.

FIG. 4 is an effect explanatory diagram.

[Explanation of symbols]

 4 ... Thermal line head, 5 ... Recording control unit, 7 ... Step motor, 50, 52 ... Delay circuit, 53 ... Strobe signal generating circuit, 54 ... Step pulse generating circuit, 55 ... Timer, 56, 58 ... Edge pulse generating circuit , 57 ... Mono-multi, 59 ... Up-down counter.

Claims (1)

[Claims] 1. A first step in which line image information read at a sub-scanning pitch of 2 / Nmm on the transmitting side is set to a 1 / Nmm pitch on the receiving side by performing sub-scanning feeding of recording paper using a step motor. And a facsimile machine which continuously reproduces the recording paper twice over the second two lines, the step motor is driven in steps of 2 m (m is a natural number) to 1 / N mm.
The recording paper feed step motor drive signal forming means, recording strobe signal forming means and recording strobe signal forming means for the first and second lines, which are in a pitch conveyance and respond to the synchronizing signal every 2 / Nmm, In response, at least a timer means for measuring a preset Tsec which is equal to or longer than the time for completing the recording of the first and second scanning lines is provided.
When the next 2 / Nmm sync signal comes within the measurement time Tsec of the timer means with reference to each sync signal, the motor is continuously driven through the first and second lines in steps of 2m. Recording is started after delaying a predetermined time from the first step for the first line and the 2m + 1 step for the second line, and is set in advance when the next synchronization signal every 2 / Nmm arrives after the elapse of the measurement time Tsec of the timer means. The step motor drive of the first line is started earlier by the predetermined time tmsec, the first line is sent in n + 2m steps, the second line is driven in 2m steps, and then in the reverse direction in n steps, and the first line is A facsimile apparatus, wherein recording is started after a delay of a predetermined time from the (n + 1) th step and the (n + 2m + 1) th step of the second line.