JPH036715B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a facsimile device that transmits information via a communication line.

A digital data exchange network (hereinafter referred to as the DDX network) that will be able to transmit high-speed, high-quality information will soon be established. The transmission speed of this DDX network is the highest
At 48Kbps, it is about five times faster than using a conventional telephone line. At this transmission speed, you can directly transfer A4 size (200mm)
x 300mm) at a density of 8 dots/mm in the main scanning direction and 8 dots/mm in the sub-scanning direction, then (200 x 8)
× (300 × 8) ÷ 48000 = 40 (seconds), but by applying band compression using encoding, which is used in conventional telephone line facsimiles, it can be reduced from 4 seconds to 5 seconds.
Transmission is possible in seconds.

Figure 1 is a block diagram of a conventional telephone line facsimile machine, Figure 2 is its timing diagram, and Figure 3 is a diagram showing the mode of document movement. 1 is the transmitter of the facsimile machine, and 2 is its output terminal. Connected to a telephone line not shown. 3 is a rubber roller, 4
5 is a driving roller, and 5 is a stepping motor. The driving roller 4 is driven by the stepping motor 5, and moves the document 6 held between the rubber roller 3 and the driving roller 4 in the direction of arrow X. 7 is a lens, and 8 is an image sensor, in which information for one line in the main scanning direction of the information written on the document 6 is imaged on the image sensor 8 by the lens 7, and a readout signal S ₈ (second When it receives the image signal S ₁ (shown in FIG. 2A), it is converted into an image signal S 1 (shown in FIG. 2A; the numbers in the blocks indicating the signals each indicate a line number). An amplifier 9 amplifies the image signal _S1 converted by the image sensor 8. 10a, 10
b is a line memory that stores image signals S ₂ (shown in FIG. 2B) and S ₃ (shown in FIG. 2C) for one line, respectively. 11 is an encoder with line memories 10a,
Image signals S ₂ and S ₃ stored in 10b are read out and converted into encoded signals. 12a and 12b are buffer memories each containing one line of encoded signal S ₅ output from the encoder 11 (shown in FIG. 2, E).
S ₆ (shown in FIG. 2F) is stored. Reference numeral 13 denotes a transmitter, which reads the encoded signals S ₅ and S ₆ stored in the buffer memories 12b and 12b, and transmits the transmission signal S ₇
(shown in Figure 2, G) to the telephone line.
14, 15, 16, and 17 are switches, and 18 is a driver which drives the stepping motor 5 in response to a drive signal _S10 (shown in FIG. 2). 19 is a controller which connects the image sensor 8 to an encoder 11, a transmitter 13,
A read signal S ₈ , an actuation signal S 9 , and a drive signal S ₁₀ that control the operations of the switches 14, 15, 16, ₁₇ and the driver 18 are output at the timings shown. Next, the operation will be explained.

Immediately before time _t0 , the image sensor 8 finishes reading out the information on the #2 line, and the line memory 10a and buffer memory 12a are empty.
The line memory 10b stores the #2 line image signal, the buffer memory 12b stores the #1 line encoded signal _S6 , and the switches 14, 1
5, 16, and 17 are respectively connected on the opposite side from the illustrated position.

Next, at time t ₀ , the controller 19 receives an operation end signal (not shown) from the encoder 11 and the transmitter 13 and sends out an activation signal S ₉ .
4 to 16 are respectively switched to the illustrated positions, and the encoder 11 reads out and encodes the image signal _S3 of the #2 line from the line memory 10b,
The buffer memory 12a stores this encoded signal _S5 , and the transmitter 13 stores the encoded signal S5 in the buffer memory 12b.
The operation of reading out the encoded signal S ₆ of the #1 line and sending it out as the transmission signal S ₇ is started, and the former storing operation ends at time t ₃ and the latter sending operation ends at time t ₄ . At the same time, the driver 18 receives the drive signal _S10 sent from the controller 19 at time _t0 , drives the stepping motor 5 at a constant speed until time _t1 , and moves the document 6 in the sub-scanning direction up to the next #3 line. It is moved by a distance h (shown in FIG. 3) and then stopped. Next, the controller 19 sends out a readout signal _S8 at a time _t2 when the original 6 has completely stopped, and the image sensor 8, which has received this readout signal _S8 , sends out an image signal _S1 for the #3 line. This signal _S1 passes through the amplifier 9 and the switch 14 and is stored in the line memory 10a.

The transmitter 1, which has thus finished transmitting one line's worth of encoded signals to the telephone line and reading them into the line memory, transmits the actuation signal _S9 and drive signal _S10 again at the next time point _t5 . Then, the same operation is repeated to read the original line by line and sequentially send out the encoded transmission signal _S7 until the information on the entire surface of the original 6 has been transmitted.

In the telephone line facsimile constructed in this way, the time required to move the document 6 by the distance h is uniquely determined by the performance of the stepping motor 5, and the current fastest one is 2.5~3.
It takes msec. If a conventional device is to be applied to a DDX network facsimile machine and operated at high speed, the document feeding time must be 0.5 to 0.6 msec. However, in order to carry out intermittent paper feeding operations within such a short period of time, a sufficiently rigid paper feeding mechanism and an extremely high output motor are required to drive the mechanism. According to the inventors' studies, the natural frequency f ₀ of the paper feeding mechanism and the power rate Q ₀ of the motor must satisfy the following values: f ₀ ≧2KHz and Q ₀ ≧625Kwatt/sec. However, the maximum f ₀ of current telephone line facsimile equipment is approximately 400 Hz, and the maximum f ₀ of commercially available motors is approximately 400 Hz.
The maximum is 265Kwatt/sec. Therefore, it is extremely difficult to set the document feeding time to 0.5 to 0.6 msec. Further, if the document is driven intermittently at high speed, the noise and vibration will become extremely large, and there is also the problem that countermeasures against noise and vibration are required. To solve this problem, a configuration has been proposed in which the document is sent at a constant speed, the read information is encoded, all of it is stored in a large-capacity memory, and then it is transmitted all at once through a DDX network. This would make it possible to realize a DDX network facsimile using a device with both natural frequency f ₀ and power rate Q ₀ comparable to that of a current machine, but it would require a huge amount of memory and be extremely expensive. Not practical.

The purpose of this invention is to put into practical use a facsimile device for a DDX network using a paper feed mechanism and a motor equivalent to that of current machines.

FIG. 4 is a block diagram of an embodiment of the present invention, FIG. 5 is a timing diagram thereof, and FIG. 6 is a diagram showing the mode of document movement. 20a and 20b each move one block (four lines in this example). ₂₁ is the number of bits _of the encoded signal sent from the encoder 11. Counters 22a and 22b for counting m are buffer memories for storing one block (4 lines) of encoded signals S ₅ (shown in FIG. 5 E) and S ₆ (shown in FIG. 5 F), respectively. , 23 is 1 counted by counter 21
A function generator arithmetic circuit whose variable is the number m of bits of the encoded signal for a block; 24 is a drive signal S ₁₀ (fifth
The rotation speed changes according to the waveform (shown in Figure 1).
It is a DC motor.

FIG. 7 shows the speed V(t) of the document 6 in this embodiment.
The present invention is fundamentally different from the conventional device in that image signal reading and signal processing are performed for multiple lines as one block. The point is that one block's worth of image signals is read out while the original is being moved. The operation of this embodiment will be explained below, focusing on the differences from conventional devices.

Immediately before time _t0 , the information on the original 6 has been read up to the (k-1)th block, the original 6 has stopped, the speed is zero, and the switches 14, 15, 16, 17 is set by the controller 19 on the opposite side from the position shown in FIG. 4, and the line memory 20b stores the image signal S of the (k-1)th block converted by the image sensor 8. ₃ (shown in FIG. 5C) is stored in the buffer memory 22b, and the encoded signal _S6 (shown in FIG. 5F) of the (k-2)th block converted by the encoder 11 is stored in the buffer memory 22b. ) is stored in the counter 21 in the function generator 23.
The drive time T ₀ and displacement x of the original 6 are determined using the number m _k-2 of bits of the coded signal S ₆ of the two previous blocks, that is, the (k-2)th block counted by
(t) and velocity v(t) are respectively calculated by the following equations and input to the controller 19.

T ₀ =m _k-2 ×τ _b ………(1) x(t)=4h/T ₀ {(t−t ₀ )−T ₀ /2πsin2π/T ₀ (
t−t ₀ )} ………(2) v(t)=4h/T ₀ {1−cos2π/T ₀ (t−t ₀ )}……
(3) However, (h is the line interval (x direction = sub-scanning direction), τ _b is the processing time for one code bit, and then at time _t0 , the controller 19 sends the driver 18 the speed v( A drive signal S ₁₀ (shown in Figure 5) proportional to DC
The motor 24 starts driving the original 6 in the x direction according to the displacement x(t) calculated by equation (2), and stops at the position where the original 6 has been displaced by 4 hours after the driving time T ₀ (time t ₄ ). let During this period, the displacement x(t) of the original 6 calculated by the controller 19 according to equation (2) is reached at times t ₁ , t 2 , t 3 , and t 4 when the displacement x(t) of the original 6 is equal to h, _2h , _3h , and _4h. Each time a readout signal S ₈ (shown in Figure 5-1) is sent out, the image sensor 8 reads out the information of the k-th block one line at a time, and these image signals S ₁ (shown in Figure 5-A) are sent out. is stored in the line memory 20a via the amplifier 9 as an image signal S ₂ (shown in FIG. 5B). At the same time, the encoder 11 and the counter 21 are activated by the actuation signal _S9 (shown in FIG. ₅ ) sent from the controller 19 at time t0, and the (k-1)th The image signal S ₃ (shown in FIG. 5C) of the block is encoded by the encoder 11, and this encoded signal S ₄ (shown in FIG.
The number of bits of the encoded signal for one block is determined by
After counting m _k-1 , the operation is stored in the buffer memory 22a as an encoded signal _S5 (shown in FIG. S ₆ (shown in FIG. 5) is read out by the transmitter 13, and the transmission signal (shown in FIG. 5) and transmission to the DDX network connected to the terminal 2 are started, and the former The storing operation of the latter ends at time _t5 , and the sending operation of the latter ends at time _t4 . Next, between time t ₅ and t ₆ when the counter 21 has counted the number of bits m _k-1 of the encoded signal of the (k-1)th block, the function generator 23 calculates the next (k+1) bits. ) To read the information of the block, drive time T ₀ , displacement x(t), speed v of the original 6
(t) is calculated by the following equations (4), (5), and (6) based on m _k-1 .

T ₀ =m _k-1 ×τ _b ………(4) x(t)=4h+4h/T ₀ {(t−t ₆ ) −T ₀ /2πsin2π/T ₀ (t−t ₆ )} ……… (5) v(t)=4h/T ₀ {1−cos2π/T ₀ (t−t ₆ )}……
(6) Next, at time t ₆ , an activation signal is sent from the controller 19.
S ₉ , drive signal S ₁₀ is sent out and switches 14,1
5, 16, 17 are switched and the line memory 20a
The operation of reading the image signal _S2 of the k-th block from the buffer memory 22b and storing the encoded signal _S6 in the buffer memory 22b, and reading the encoded signal _S5 of the (k-1)th block stored in the buffer memory 22a. Then, at time points _{t 7 ,} t ₈ , t ₉ , and t ₁₀ , a read signal S ₈ is sent from the controller 19, and the image sensor 8 finally reads one line. The operation of reading the image signal _S1 of the (k+1)th block every minute and storing it in the line memory 20b is performed in the same manner as the previous time, and ends at time _t11 . Next, the function generator generates the following (k+2) based on the number of bits m _k of the k-th block counted between time t ₁₀ and t ₁₂ .
In order to read the information of the th block, the drive time T ₀ , displacement x(t), and velocity v(t) of the original 6 are calculated using the following formula.
Calculated by (7), (8), and (9).

T ₀ =m _k ×τ _b ………(7) x(t)=8h+4h/T ₀ {(t−t ₁₂ ) −T ₀ /2πsin2π/T ₀ (t−t ₁₂ )} ………(8 ) v(t)=4h/T ₀ {1-cos2π/T ₀ (t-t ₁₂ )}...
...(9) All the information in document 6 is the transmission signal for this kind of operation.
This is repeated until it is sent as S ₇ .

In the above explanation, one block has four lines, but it goes without saying that the number of lines can be arbitrarily selected.

Now, if one block is n lines, the drive time of one block of original calculated by the function generator 23 is T ₀
The displacement x(t) and velocity v(t) are T ₀ = m×τ _b ………(10) x(t)=nh/T ₀ (t−T ₀ /2πsin2π/T ₀ t)…… (
11) v(t)=nh/T ₀ (1-cos2π/T ₀ t) ......(12). In this way, the original 6 and the DC motor 24
According to the inventors' study, the natural frequency f ₀ of the paper feeding mechanism is
The power rate _Q0 of the motor required for driving is proportional to the number of lines in one block, 1/n and 1/ ⁿ² , respectively.
For DDX network facsimile, it is sufficient to satisfy the following formula.

f ₀ ≧1/n×10 ³ (Hz) ………(13) Q ₀ ≧1/n ² ×385 (Kwatt/sec) ………(14) If n=10, f ₀ ≧100 (Hz) Q ₀ ≧3.85 (Kwatt/sec), which is a value that can be used sufficiently for the mechanisms used in telephone line facsimiles and commercially available motors. Also, manuscript 6 at the beginning and end of one block.
Since the speed and acceleration of the DC motor 24 are set to zero, the movement of each block of the original 6 and the DC motor 24 is extremely smooth, and the movements of the original 6 and the DC motor 24 are performed according to equation (11). Noise and vibration are sufficiently reduced. Furthermore, in order to process one block of information at a time, most of the systems employed in telephone line facsimiles can be applied to the DDX network facsimile according to the present invention.

Although the above explanation has been limited to the transmitter, it goes without saying that the receiver can also be configured in the same way. Further, in the transmitter, the lens 7 and the image sensor 8 are kept stationary and the original 6 is moved in the x direction, but the original 6 may be fixed and the lens 7 and the image sensor 8 moved. Alternatively, a mirror may be arranged on the optical path of the original 6, the lens 7, and the image sensor 8, and this mirror may be rotated to perform sub-scanning. In other words, it is sufficient that the scanning displacement in the sub-scanning direction on the original 6 and the scanning speed satisfy equations (11) and (12).

Furthermore, in the above explanation, the displacement x(t) and velocity v(t) calculated by the function generator 23 are limited to the cases expressed by equations (11) and (12), but they may be replaced by the following functions. .

x(t)=60nh/T ₀ ⁶ {1/5t ⁶ −T ₀ /2t ⁵ +T ₀ ² /3t ⁴
} ………(13) v(t)=60nh/T ₀ ⁶ t ³ (t−T ₀ ) ² ………(14) Figure 8 shows the characteristics of this function and the equations (11) and (12). The characteristics of the expressed function are shown (solid lines in the figure are equations (13) and (14)
, and the broken lines indicate those based on equations (11) and (12). ) Alternatively, it may be driven at varying speeds as shown in FIG.

That is, it is sufficient that the sub-scanning displacement of one block is nh, and the sub-scanning velocity and sub-scanning acceleration at the start of scanning (t=0) and at the end of scanning (t=T ₀ ) of the block are zero.

Expressing this mathematically, f(t) | _t=0 = 0 f(t) | _t=T0 = nh df(t)/dt | _t=0 = 0 df(t)/dt | _t=T0 = 0 d ² f(t)/dt ² | _t=0 =0 d ² f(t)/dt ² | _t=T0 =
Any function f(t) that satisfies 0 is sufficient.

In addition, in the above explanation, the document driving time for one block is
Although T ₀ was calculated based on the number of coded bits of the block previously measured by the counter 21, it is also possible to Therefore, the driving time T ₀ for one block may be determined.

In addition, in the above explanation, the time point at which information on the document is read is determined based on the displacement of the document calculated by the function generator 23, but the point in time at which the information on the document is read is determined based on the displacement of the document calculated by the function generator 23. The document may include means for detecting the displacement of the document, thereby determining the time point at which information on the document is read. As explained above, this invention scans the surface of a document in the main scanning direction to read information and store it in a first line memory, and at the same time, the information signal of the previous line is stored in a second line memory. The operation of encoding and storing the information in the first buffer memory, and at the same time reading out the encoded signal of the information of the two previous lines stored in the second buffer memory and sending it out as a transmission signal, is performed when the document is moved in the sub-scanning direction. In a facsimile device including a signal mechanism configured to alternately and repeatedly transmit the information, the facsimile apparatus includes first and second line memories and first and second buffer memories that store a plurality of lines of information as one block. , a drive mechanism that creates a sinusoidal signal based on the number of bits of the coded signal of the previously read block, and drives the document with a speed change proportional to the signal; It is characterized in that it is equipped with a readout mechanism that sequentially reads out the information of the lines, and the information of the document is processed as a signal by treating a plurality of lines as one block.
A high-speed facsimile machine suitable for use in a DDX network can be realized using a paper feed mechanism and a drive motor of the same level as those used today.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing the configuration of a conventional telephone line facsimile device, Fig. 2 is its timing diagram, Fig. 3 is a diagram showing its document feeding mode, and Fig. 4
The figure is a block diagram of an embodiment of the present invention, FIG. 5 is a timing diagram thereof, FIG. 6 is a diagram showing the mode of document feeding, and FIG. 7 is a diagram showing the speed v(t) and acceleration α(t) of the document. FIG. 8 is a diagram showing the document feeding mode and speed v(t) of another embodiment.
FIG. 9 is a diagram showing the velocity v(t) of another embodiment. In the figure, 1 is a transmitter, 3 is a rubber roller, and 4 is a transmitter.
1 is a driving roller, 5 is a stepping motor, 6 is a document, 8 is an image sensor, 10a, 10b, 20
a, 20b are line memories, 11 is an encoder, 1
2a, 12b, 22a, 22b are buffer memories, 13 is a transmitter, 14, 15, 16, 17 are switches, 18 is a driver, 19 is a controller, 21 is a counter, 23 is a function generator, and 24 is a DC motor. . Note that the same reference numerals in the figures indicate the same or corresponding parts.

Claims (1)

[Claims] 1. The operation of sequentially scanning the document surface, converting the read information signal into a coded signal, and sending it to a transmission line is performed sequentially in synchronization with the scanning of the document in the sub-scanning direction. In a facsimile apparatus including a transmitter configured as above, a means for reading information signals of a plurality of lines while feeding the document in a sub-scanning direction, and an encoding method for encoding the read information signals of the plurality of lines as one block. and the means includes:
A counter that counts the number of codes of the encoded signal for one block that was read out and encoded earlier or the time required to encode the one block, and The time to read the information of the block to be read is calculated based on the time, and based on this calculated time, the speed in the sub-scanning direction changes sinusoidally, gradually increases from zero, and then gradually decreases. The arithmetic circuit generates a drive signal based on the above calculation time and the sub-scanning speed signal, outputs this drive signal to the motor driver, and outputs a sub-scanning speed signal that becomes zero. A facsimile apparatus comprising: a controller that outputs a read signal for each line in one block based on the displacement. 2. The facsimile apparatus according to claim 1, wherein the displacement of the document in the sub-scanning direction is calculated by an arithmetic circuit based on the counted number of codes or the time required for encoding. 3. The facsimile machine according to claim 1, wherein the displacement of the original in the sub-scanning direction is determined by the rotation angle detected by a detector that detects the rotation angle of a roller that drives the original. Device.