JPS6233790B2 - - Google Patents

Description

Detailed Description of the Invention The present invention provides a method for performing intermittent sub-scanning in a facsimile transmitter or the like by intermittently moving a reading unit such as an optical system that reads image information to be read in the sub-scanning direction. This invention relates to a sub-scanning control method.

When performing sub-scanning by moving the reading section in the sub-scanning direction in a conventional facsimile transmitter, etc., if you try to perform intermittent sub-scanning by moving the reading section intermittently, the reading section etc. Since the inertia is large, the moving speed of the reading section is not constant immediately after the start of movement, resulting in a significant deterioration of image quality.

Therefore, conventionally, when performing sub-scanning by moving the reading section in the sub-scanning direction,
Even when performing band compression, intermittent sub-scanning is not performed, and the reading unit is moved continuously at a constant speed from start to finish to perform sub-scanning for one screen, and the resulting one-screen portion is The image signal was once stored in memory and then subjected to band compression processing. Therefore, it has had the disadvantage of requiring a large amount of memory elements, ranging from several megabits to several tens of megabits.

The present invention has been made to solve the above-mentioned conventional drawbacks, and makes it possible to perform intermittent sub-scanning without deteriorating image quality when sub-scanning is performed by moving the reading section in the sub-scanning direction. The purpose of the present invention is to provide a sub-scanning control method.

That is, when performing one intermittent sub-scan, the present invention does not perform reading in a run-up section of a predetermined length after the reading unit starts moving forward, and starts reading for the first time after the end of the run-up section, and reads a certain section. After that, the reading section finishes advancing and reading,
After that, the reading section is moved back by a length corresponding to the run-up section.

The present invention will be explained in detail below based on embodiments shown in the drawings.

FIG. 1 shows the mechanical configuration of a facsimile transmitter to which this embodiment is applied. This facsimile transmitter is provided with a single-leaf transmitter 2 and a continuous transmitter 3.

First, to explain the monoplane transmitter 2, a transparent plate 4 is provided on the upper surface of one end side of the main body 1,
Thick manuscripts, books, etc., which cannot be transmitted by the continuous transmitter 3, are placed on the transparent plate 4 with the side to be transmitted facing downward.

In addition, inside the main body 1 and below the transparent plate 4,
A feed screw 5 is provided in the sub-scanning direction, and this feed screw 5 is connected to a step motor 6 (not shown in FIG. 1).
It is designed to be rotated by The feed screw 5 is screwed with a moving base 7 that is movably fitted into a guide bar (not shown) extending in the sub-scanning direction.

A light source 8, a condensing lens 9, and a reading element 10 are fixed to the movable table 7, and a reflecting mirror 1 is also fixed to the movable table 7.
1 is rotatably supported. The light source 8, the lens 9, the reading element 10, and the reflecting mirror 11 constitute a moving reading section 12. When the monoplane transmitting section 2 performs transmission, the reflecting mirror 11 is located at the solid line position in the figure, and the light source 8 The reflected light from the original, etc., irradiated with the light beam is incident on the reading element 10 through the reflecting mirror 11 and the condensing lens 9 as shown by arrow A.

Next, the continuous transmission section 3 will be described. A document placement table 13 is provided on the upper surface of the other end side of the main body 1, and documents stacked on this document placement table 13 are placed on top of each other by a tongue-like piece 14 and a sorting roller. After the sheets are sorted one by one by 15, they are conveyed through a path of a feed roller 16, a guide plate 17, a discharge roller 18, and a discharge guide 19.

When the continuous transmitting section 3 performs transmission, the reflecting mirror 11 is located at the position indicated by the broken line in the figure, and the original transported along the path is irradiated by the light source 20 while passing through the guide plate 17. The reflected light is made to enter the reading element 10 through the condensing lens 9 as indicated by arrow B.

FIG. 2 shows the movable reader 12 of the single leaf transmitter 2.
The block diagram of the control system for controlling the sub-scanning of the image sensor is shown.

21 is an amplification/shaping circuit, and a mobile reading section 12
The image signal read by the image signal is amplified and waveform shaped. 22 is a memory, and an amplification/shaping circuit 2
Store the output of 1.

23 is a control unit, which compresses the band of the image signal taken in from the memory 22 while controlling the memory 22, the step motor driver 24 that drives the step motor 6, and the compressed data buffer 25, and compresses the band of the obtained band compressed data. The compressed data buffer 25 stores the compressed data, and from the buffer 25 the band compressed data is transmitted at 9600bps, 7200bps,
The signal is sent to a telephone line or the like through the signal output terminal 26 using a clock of 4800 bps, 2400 bps, etc.

Next, the operation of the apparatus according to this embodiment will be explained.
First, in this embodiment, when the compressed data length is short, there is space in the compressed data buffer 25 and the memory 22, so sub-scanning is performed continuously, and image signals are read out while being written in the memory 22 one after another. .

On the other hand, if the compressed data length is long and the compressed data buffer 25 becomes empty, the memory 22 also becomes empty. Therefore, when the memory 22 is full, the sub-scanning is stopped and reading of the original is stopped. Then, when the compressed data buffer 25 becomes empty again, the memory 22 also becomes empty, so the sub-scanning is restarted.

Now, when transmitting by the continuous transmitter 3,
Since sub-scanning is performed by moving the document, the sub-scanning control method according to the present invention is not necessary when performing intermittent sub-scanning as described above.

The sub-scanning control method according to the present invention is required when the monoplane transmitter 2 performs transmission. Next, this case will be explained with reference to the timing waveform diagram shown in FIG. 3 and the flowchart shown in FIG. 4.

In this case, the control section 23 drives the step motor 6 via the step motor driver 24, which further rotates the feed screw 5, so that the movable reading section 12 along with the movable table 7 can perform the sub-scanning. be moved in the direction. Here, the movable reading section 12 moves forward (in the direction of arrow C) when the step motor 6 rotates in the normal direction, and moves backward when the step motor 6 rotates in the reverse direction. Also, the step motor 6
The distinction between forward and reverse rotation and the amount of rotation are determined by a forward/reverse rotation signal and a step pulse input from the control section 23 to the step motor driver 24, respectively.

In the case where the monoplane transmitter 2 performs transmission, if the memory 22 becomes empty, the controller 2
sends a step pulse and a forward rotation signal to the step motor driver 24 to move the movable reading section 12 forward. However, after the movable reading section 12 starts moving forward, image information of the document or the like is not written into the memory 22 during the run-up section D of a predetermined length shown in FIG.

The run-up section D is a rising period until the moving speed of the movable reader 12 reaches a constant speed (inertia of the drive system such as the movable reader 12, the movable table 7, and the step motor 6, the torque of the step motor 6, etc.). The predetermined length is determined according to the number of step pulses.

Next, when the run-up section D ends, the image information of the original document etc. is written into the memory 22 for the first time (during this time, the movable reading section 12 continues to move forward). When the memory 22 is empty, the control unit 23 causes the reading element 10 to stop reading, and at the same time stops driving the step motor 6 and stops the movement of the movable reading unit 12.

The section in which the above reading is performed is indicated by E in FIG. The maximum length is the length of one screen. In this reading section E, the moving speed of the movable reading section 12 is constant, so that accurate sub-scanning is performed.

Next, after the reading section E ends, the control section 23 sends a reverse rotation signal and the same number of step pulses as the run-up section D to the step motor driver 24.
The movable reading section 12 is moved backward by the same length as the run-up section D, as shown in the retreat section F shown in the figure. This completes all operations related to one intermittent sub-scan.

Then, if the memory 22 becomes empty again,
The control section 23 again sends a normal rotation signal and a step pulse to the step motor driver 24 to move the movable reading section 12 forward, and thereafter repeats the intermittent sub-scanning in the same procedure as the previous time.

Here, as described above, after one reading is completed, the movable reading unit is moved back by the same length as the run-up section D, so the part read in one intermittent sub-scan and the part read in the next intermittent sub-scan There are no skipped parts between the Furthermore, since the compressed data buffer 25 continues to send compressed data during the run-up section D and the retreat section F, the transmission time will not become longer due to the presence of the run-up section D and the retreat section F. do not have.

As described above, in the sub-scanning control method according to the present invention, when performing one intermittent sub-scanning, after the reading unit equipped with an optical system etc. starts moving forward, reading is not performed in the predetermined length of the approach section, and the approach After the end of the section, reading is started for the first time, and after reading a certain section, the reading system advances and finishes reading,
After that, by retracting the reading section by a length corresponding to the run-up section, reading is performed after the moving speed of the reading section reaches a constant speed, so image quality is not degraded as in the conventional method. This provides an excellent effect in that intermittent sub-scanning can be performed without any problems.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing a facsimile transmitter according to an embodiment of the sub-scanning control method according to the present invention;
FIG. 3 is a block diagram showing the control system of the embodiment, FIG. 3 is a timing waveform diagram for explaining the embodiment, and FIG. 4 is a flowchart of the control procedure in the embodiment. 2... Monoplane transmitter, 6... Step motor, 8
... Light source, 9 ... Condensing lens, 10 ... Reading element, 11 ... Reflector, 12 ... Moving reading section, 22
. . . memory, 23 . . . control section, 24 . . . step motor driver.

Claims (1)

[Claims] 1. A reading means for photoelectrically converting information on a document, a step motor capable of forward and reverse rotation for moving this reading means in the sub-scanning direction relative to a stationary original, a memory for temporarily storing the output of the reading means, and this memory. and a control unit that compresses the output signal from the memory, monitors the remaining storage capacity of this memory, and controls the step motor, and when the memory runs out in the middle of one document, the step motor is compressed. The step motor is stopped and reading is interrupted, the step motor is reversed for a period necessary for the step motor to rotate at a constant speed, and then the step motor is rotated in the forward direction and reading is restarted from the reading interruption position. A sub-scanning control method.