JPS6374253A - Digital copying machine - Google Patents

Abstract

PURPOSE:To correct the distortion of a picture by controlling the drive of a step motor in constant speed, deceleration, stop or accelerating state in the case of stop/restart of read operation and transferring the read picture signal to a storage means at a transfer period corresponding to the deceleration of the step motor. CONSTITUTION:When an original is a long sheet, a detection signal is outputted when a picture signal is transferred to a page memory up to a prescribed address M before overflow. When the storage quantity to the page memory 4 reaches a prescribed quantity, the step motor is decelerated at a prescribed deceleration ratio. A system control section 1 controls the interval of DMA start signals given to a DMA controller (b) so as to be longer corresponding to the deceleration ratio of the step motor. When the recording is finished, the read is started, then the system control section 1 accelerates the step motor at a prescribed acceleration. A picture signal read by a reader 2 is subject to DMA transfer to the page memory 4.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a digital copying apparatus, and more particularly to a copying apparatus using cut paper.

(1) Prior Art Recently, a plain paper recording type factor cutting device has been put into practical use, which incorporates electrophotographic PP0 (plain paper copying machine) technology in the printing section for the purpose of high-speed, high-definition recording. Such a facsimile device was published in the Telecommunication Research Institute Research and Practical Application Report No. 3.
Volume 3, No. 1 (1984) K, pages 197 to 2
This is disclosed in the article "Ultra-high-speed facsimile device" on page 06.

With the facsimile IJ device mentioned above, both the image quality and speed are similar to those of a copying machine.If you pay attention to the copying speed and resolution, the resolution is 16 lines/l1ffi, and the A4 size is 15~15 lines/l1ffi.
Comparable to a ppaO medium speed machine of 30 sheets/min. Therefore, this facsimile device can be used as a digital copying device.

Incidentally, the document reading device in such apparatus K is a stationary document reading device in which a document to be transmitted is placed on a document mounting table and a reading system is moved to perform sub-quantification. Even in this type of device, if a moving document reading device is added that reads N documents while feeding them using a drive system C whose drive source is a step motor (hereinafter referred to as a feeder), it is possible to It will be possible to make copies of "Shakumono" manuscripts.

(c) Problems to be solved by the invention When copying a "long document" document using a copying machine that uses cut paper cut into a predetermined size, multiple sheets of recording paper are used. It is necessary to perform separate recording.

When performing divided recording using the above-described moving document reading device, the reading operation is stopped and restarted. At the time of stopping or restarting, there is a delay in response to the stop or restart control command due to the inertia of the feeder and the document in the document conveyance operation by the feeder. For this reason, images read at the time of stopping and restarting are distorted in the sub-scanning direction.

The present invention provides a digital copying apparatus that corrects image distortion caused by a delay in response to document conveyance when stopping and restarting a reading operation.

(b) Means for Solving the Problems The digital copying apparatus of the present invention includes a reading means for reading and scanning an original conveyed by a drive system using a step motor as a drive source, and outputting an electrical image signal. storage means for storing the image signal read by the means; means for transferring the image signal to the storage means; recording means for recording based on the image signal stored in the storage means;
A storage state detection means for detecting that the storage state of the storage means has been stored up to a predetermined area, and a control means for controlling the drive of the step motor to a constant speed, deceleration, stop, or acceleration state. shall be.

(e) Effect 1 When copying a long original, during the reading operation, before the output from the detection means, the step motor is driven at a constant speed, and the read image signal is transferred to the storage means at a constant transfer cycle; After the output of the detection means, the image signal read while decelerating the step motor at a predetermined deceleration rate is transferred to the storage means at a transfer cycle corresponding to the deceleration, and after the step motor stops, the image signal stored in the storage means is transferred to the storage means. After recording a predetermined amount of data using the recording means, the step motor is accelerated to a constant speed at a predetermined acceleration rate, the read image signal is transferred to the storage means at a transfer cycle corresponding to the acceleration, and the image signal in the storage means is Make a record. In this way, when copying the Shokushakuho manuscript, the distortion of the image is corrected and the image is divided and recorded onto a plurality of recording sheets.

(F) Embodiment FIG. 1 is a block diagram of a digital copying apparatus according to an embodiment of the present invention. The copying apparatus includes a system control section (1). The system control section (1) is composed of a microcomputer, and if we focus on its functions, it includes a main controller and an internal memory, and the main controller is shown in FIG. 5 described later. The internal memory includes an area for storing data necessary for transmission processing such as document reading, a flag area for storing various operating states, and the like.

Reading device (2) connected to system control unit (1)
includes a document feed mechanism driven by a step motor, a light source,
It consists of an optical lens system, a photoelectric conversion circuit, and an image signal binarization circuit. A system control unit (1) outputs a normal rotation pulse of a step motor and a reading start signal of an image signal to a reading device (2) in response to a timer interlock of a microcomputer. And the reading device (
21 is 1 after a certain time delay from the reading start pulse.
The binarized image signal for each line is output as a bit-by-bit time-series signal.

Serial-to-parallel conversion circuits C and S are inserted between the reading device (2) and the page memory (4) described later.
/P circuit. )(3) converts the image signal output as a bit-based time-series signal from the reading device (2) into an image signal of byte-based time-series data, and outputs it to the system data bus.

A page memory (4) acting as a storage means is connected to the system control K(+[1), and this page memory (
4) converts the image signal output from the reading device (2) into 8
72 circuit (3) converts it into an image signal of time-series data in bytes and stores it. And this page mesori (4)
includes a storage area for a predetermined number of pages (for example, one page of a manuscript).

Key switch (5) connected to system @ section (1)
sets the number of copies, derives the copy start signal, etc.

DMA (direct memory) acts as a transfer means.
The access) controller (6) is a system control unit (1
), the image signal from the reading device (2) is DMA-transferred to the page memory (4) as a storage means via the S/P conversion circuit (3), or the image signal is transferred to the page memory (4) as a storage means. Parallel/serial of written image signals! The conversion circuit C is hereinafter referred to as a P/S conversion circuit.

) (7) and the interface (8) to perform DMA transfer to the recording device (9).

The recording device (9) includes a printing section using an electrophotographic method or the like, and records a copy image based on an input image signal.

FIG. 2 is a schematic side view showing the relationship between the continuing position of the reading device and the position of the document detection sensor.
) is turned off, the document is fed and read for a predetermined line (5247 minutes), and the document reading operation is completed. In the ycz diagram, (22+ is the distance between the document driven by the step motor and the reading position c!l is the document feed distance (corresponding to the U line).

Fig. 3 is a characteristic diagram showing the relationship between the motor pulse when the step motor is decelerated and the displacement of the document feed, and the relationship between the start of reading, the signal, and the transfer timing of the image signal C from the reading device to the page memory. FIG. 6 is a characteristic diagram showing the relationship between a motor pulse during motor acceleration and document feed displacement, and the relationship between a reading start signal and the timing of transferring an image signal from the reading device to the page meander.

In this embodiment, when transferring to the page memory, the DMA controller (6
).

Next, the specific operation of this embodiment will be explained with reference to the flowchart of FIG. 5, focusing on the operation of the system control section. When the start of copying is instructed by the key switch (5), in step S1, the document a! Initial conditions for the reading operation, such as the number of copies, are set, and the process proceeds to step S2.

In step S2, the motor constant speed 1 movement 7 lag is set,
In order to drive the step motor at a constant speed, a constant pulse is output, and the process proceeds to step S3. By driving the motor at a constant speed, a constant motor pulse is applied to the step motor, and constant-speed document conveyance is started. Further, a reading start signal is given to the reading system d(2) n1
A binary image signal for one line is output from the reading device (2). At the time of starting copying, as shown in the second screen, a predetermined number of lines ((
5247 minutes), so the above-mentioned reading operation is started after the sensor is turned on and moves L line. Also, during this period, in consideration of the response delay of the feed system, etc., in step S3, a wait is made in advance to determine whether the motor has advanced by one step, that is, until the document has moved by one line, and then the process proceeds to step S4. In step S4, the image signal read by the reading device (2) is sent to the DMA controller (6) at a constant speed timing, that is, at a timing corresponding to the output of a constant speed motor pulse, to the page memory (4). Outputs the DMA start signal to start and transfers the image signal to the page memory (4).
Transfer MA. That is, the step motor feeds the document by one line, and the read image signal for one line is output to the s/p industrial odor circuit (3), and serial/parallel conversion is performed by the q/p mantle circuit (3) K. The resulting image signal is processed by the DMA controller (6).
4).

In step S5, it is determined whether the end of the document has been detected by the document detection sensor. Immediately after the start of the copying operation, it is determined that the end of the document has not been detected (n1 step S6).
Then, when the end of the document is detected, step 81
Proceed to B. In step S6, it is determined whether a predetermined number of lines have been read, that is, whether a predetermined soft memory has been stored in the page memory (4).If the predetermined number of lines has not been reached, the process returns to step S5. The above operations are repeated until the end is detected or a predetermined value is stored.

As mentioned above, the page memory (4) is selected to have a capacity that can easily store one document if the document size is within a predetermined size. If the document is long, the page memory may overflow, so a detection signal is output when the image signal is e-transferred to the page memory up to a predetermined address M before overflow. That's what happens. In addition, as will be described later, the remaining storage capacity of the page memory (4) is set at address M so that image signals read before the feeder stops are stored in consideration of the delay in response of the drive system to motor pulses. It is determined.

When the storage in the page memo (January 4) reaches a predetermined value I, in step S7, the motor deceleration drive is first set to stop the conveyance of the document, and the process proceeds to step S8. The system control unit (1) outputs a motor pulse that reduces the speed of the step motor at a predetermined reduction ratio, thereby decelerating the step motor. This reduction ratio is determined in consideration of the responsiveness of the feed system.

In step S8, the motor waits until it has advanced one step, that is, until one line of original has been conveyed, and the process proceeds to step S9.
DM the image signal read in 2) to the page memory (i+1)
Ak is sent and the process proceeds to step S1 [). At this time, the system control unit (1) sends the DM to the DMA controller (shi).
The interval between the A start signals is controlled to be longer in accordance with the reduction ratio of the step motor. By controlling in this way, as shown in FIG. 5, the reading pitch after the start of deceleration is made equal to the reading pitch at constant speed (Pltc).

In step 810, it is determined whether reading of one page of the document has been completed. If not, the process returns to step S8 and the above-described operations are repeated. At this time, the reduction ratio is controlled to gradually increase. In step 810, when it is detected that reading for one page has been completed, the process advances to step 81).
), the motor is stopped, the document reading operation is stopped, and the process advances to step 912.

In step 312, the recording device (9) records on recording paper based on the image signal stored in the page memory (4), and when the recording is completed, the process advances to step 313. At this time, if it is set to record a plurality of sheets in step S1, recording is performed according to the set number of sheets.

In step 813, a reading restart flag is set to start the reading operation, and the process proceeds to step 814.

In step 314, a motor acceleration drive is set in which the interval between the heptad pulses is gradually shortened until constant speed drive is reached, contrary to the case of deceleration, and step! Proceed to 315. In step 814, the system control unit (1) outputs a motor pulse that accelerates the step motor at a predetermined acceleration ratio to accelerate the step motor.

In step S15, the process waits to determine whether Tanabata has advanced one step, that is, until one line of the document has moved, and then proceeds to step S316. In step S16, the image signal read by the reading device (2) is DM'ed to the page memory (4).
Transfer A and proceed to step 817. At this time, the system control unit [1] provides the DMA controller unit
The interval between start signals is controlled to correspond to the acceleration rate of the step motor. In this way, by controlling
As shown in the figure, the reading pitch IP+ after the start of acceleration
When read at constant speed, it becomes equal to pitch CP+. Therefore, it is possible to eliminate image distortion caused by a delay in response until the constant speed pitch is reached immediately after startup.

In step 817, it is determined whether the acceleration has ended, that is, whether the acceleration has ended and the step motor has reached a speed corresponding to constant speed drive. If acceleration is still required, step 815 Go back and repeat the above steps,
When the acceleration ends, the process returns to step S2.

Then, from step S2, steps 83 to S6 are repeated with constant speed driving, and when a predetermined amount of image signals are stored in the page memory (4) during that time, steps 87 to 8 are performed.
Repeat step 18. By repeating the above operations, when the edge of the document is detected in step 85, step 81
Proceed to Step 8, and after reading the distance 5242 minutes between the sensor and the reading position, stop the motor, and then proceed to Step 81.
At step 9, the image signal stored in the page memory (4) is recorded by the recording device (9), and when this recording is completed, the copying operation is completed.

C.1 Detailed Description of the Invention As described above, according to the present invention, it is possible to eliminate image distortion caused by stopping and restarting the reading operation when dividing and recording a "long document" document. Therefore, it is possible to easily copy "long" originals without image distortion.

[Brief explanation of the drawing]

Fig. 1 is a block diagram showing an embodiment of the present invention, Fig. 2 is a schematic side view showing the relationship between the reading position of the reading device and the position of the document detection sensor, and Figs. 3 and 4 are the document feed displacement step motor. Figure 3 is a characteristic diagram showing the relationship between the motor pulse, reading start signal, and transfer timing. Figure 3 shows the time of deceleration, Figure 4 shows the time of acceleration, and Figure 5 is a flow diagram to explain the operation of the system control section. be. 1... System control unit, 2... Reading device,
4-page memory, 6... DMA controller,
9...Recording device

Claims (1)

[Claims] (1) A reading means for reading and scanning an original conveyed by a drive system using a step motor as a drive source, and outputting an electrical image signal, a storage means for storing the image signal read by the reading means, and a storage means for storing the image signal read by the reading means; Transfer means for transferring the signal to the storage means; Recording means for recording based on the image signal stored in the storage means; Storage state detection means for detecting that the storage state of the storage means has been stored up to a predetermined area; control means for controlling the drive of the step motor to a constant speed, deceleration, stop, or acceleration state; during a reading operation, before the output of the detection means, the step motor is driven at a constant speed and the read image signal is is transferred to the storage means at a constant transfer cycle, and after the output from the detection means, the step motor is decelerated at a predetermined deceleration rate, and the read image signal is stored in the storage unit at a transfer cycle corresponding to the deceleration. After the step motor is stopped, a predetermined amount of the image signal stored in the storage means is recorded by the recording means, and the read image signal is accelerated while accelerating the step motor at a predetermined acceleration rate to a constant speed. A digital copying apparatus characterized in that the data is transferred to the storage means at a corresponding transfer cycle.