JP3236771B2 - Facsimile machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a personal computer as an external device for outputting image data to be printed, and a personal computer (RS).
The present invention relates to an improvement of a facsimile apparatus capable of performing transmission and reception via a communication line based on the H.232C protocol or the like.

[0002]

2. Description of the Related Art Conventionally, in this type of facsimile machine,
When image data is received from a personal computer via RS-232C and printed, the encoding / decoding processing of the image data is performed as follows.
A preset method is adopted.

In such a case, even if the communication speed and resolution of transfer data increase and the processing load increases, the processing capability of the CPU remains unchanged. Also, in response to a request for hardware cost reduction, the CPU performs all controls by itself, so when performing encoding / decoding processing of image data, other processing is performed until the processing is completed. Can not do.

[0004]

However, in the above-mentioned conventional apparatus, if the resolution of the image data is increased, the encoding / decoding processing of the image takes a long time. On the other hand, when receiving the transfer data, the interruption process to the RS-232C interface is performed at a fixed time interval, and the time interval is reduced in proportion to the communication speed.

[0005] Therefore, if the time for decoding image data is longer than the time interval for interrupt processing to the RS-232C interface during high-speed communication, the RS-
Image data transferred via the H.232C cannot be processed. As a result, accurate reception of transfer data becomes impossible, resulting in data abnormalities. That is, interrupt 1
The reception of the transfer data for the first time cannot be performed reliably,
The image data for the line is lost.

[0006] This data abnormality is caused by a two-dimensional coding method (M
In the case of adopting R), if an abnormality occurs in one line, another (subsequent) line to be decoded with reference to the line also becomes abnormal, and there is a problem that the image abnormality becomes remarkable.

[0007] The present invention has been made in view of the above,
It is an object of the present invention to provide a facsimile apparatus that can prevent occurrence of abnormal image reception without performing any special device or complicated processing even during high-speed communication.

[0008]

SUMMARY OF THE INVENTION In order to solve the above problems, the present invention relates to a facsimile apparatus which sequentially decodes and prints encoded image data transferred from an external device. A decoding unit for selectively decoding the data according to the first and second encoding methods, and a selecting means for switching the encoding method according to the conditions of the communication speed and the resolution of the transfer data; The selecting means determines that the one-dimensional encoding method (M) is used when the communication speed of the transfer data is higher than a predetermined communication speed and the transfer data is higher than a predetermined resolution.
H), and when the resolution is smaller than a predetermined resolution, the decoding is performed by a two-dimensional encoding method (MR).

Thus, when data is transferred from the personal computer at high speed, the data to be transferred is selected by the selecting means.
Depending on the communication speed and resolution of the data, an appropriate coding method is adopted from one-dimensional and two-dimensional coding methods, and the image data is sequentially decoded by this adopted method and printed on recording paper. You.

[0010]

FIG. 1 is an overall perspective view showing an embodiment of a facsimile apparatus according to the present invention, and FIG. 2 is an internal configuration diagram thereof.

The facsimile apparatus comprises an apparatus main body 1 and an automatic document feeder mechanism 2 disposed on the top of the apparatus main body. The apparatus main body 1 comprises a scanner unit 3 as an optical mechanism, an image forming unit 4, a paper cassette unit. 5, a paper transport mechanism 6, and an operation panel 7 so that an image can be formed.

The automatic document feeder 2 includes a document table 8,
A document conveying path 9 having a circulation path is provided on the right side thereof, and a sheet feeding roller 10, a separating roller pair 11, a conveying roller pair 12, a feeding roller 13, and A discharge roller pair 14 is provided. A contact glass 15 for reading an image is provided between the pair of transport rollers 12 and the feed roller 13. In addition, a contact glass 16 is disposed at an opening on the top surface of the apparatus main body 1 over substantially the entire length. The feed roller 10 is a document table 8
The upper stack of originals is in contact with the upper surface of the leading end by an arm (not shown), and the originals are sent out by their weight. The fed document is separated one by one by a separating roller pair 11, and then transported to a document reading position on the contact glass 15 via a transport roller pair 12. And
After reading the original, feed roller 13 and discharge roller pair 1
4, the document is returned from the document conveying path 9 to the lowest position on the document table 8. The paper feed roller 10 is configured to be synchronously rotated by a belt hung on a forward rotating roller of the separating roller pair 11.

The scanner unit 3 has a light source section 31 having a halogen lamp for scanning a document located on the contact glass 15 or 16, and the light from the light source section 31 is reflected by the document surface. The reflected light is guided through a plurality of reflecting mirrors 32a to 32e and a lens 33 to a CCD 34 in which optical sensors are arranged in an array parallel to the main scanning direction, and a document image is formed on the CCD 34. It is designed to receive light. That is, the light reflected on the original surface on the contact glass 15 is sequentially reflected by each of the reflecting mirrors 32a to 32e as shown by a dashed line in FIG. The light is sequentially received by the CCD. Also, CC
The image data for each line received in D34 is sequentially
After being sent to the image processing unit 35 and subjected to predetermined image processing as needed, it is stored in the storage unit 101 (see FIG. 3).

It is also possible to manually set the original on the contact glass 16 by lifting the front and rear sides of the automatic original transport mechanism 2. In this case, a travel guide or travel drive motor (not shown) is used. The scanner unit 3 is caused to travel at a predetermined speed in the direction of the dashed line arrow (sub-scanning) in the figure to scan the original surface of the set original.

The image forming section 4 includes a laser beam emitting section 40 and a photosensitive drum 41 which is driven to rotate clockwise by a driving means (not shown). Main charging unit 4 from upstream
2, developing unit 43, transfer unit 44, and cleaning unit 4
5 is formed. After the surface of the photosensitive drum 41 is uniformly charged by the main charging unit 42, the photosensitive drum 41 is exposed to the modulated original image from the laser emitting unit 40 to form an electrostatic latent image. The electrostatic latent image is made visible by attaching toner in the developing unit 43, and then transferred to recording paper in the transfer unit 44. Reference numeral 431 denotes a toner cartridge, and 432 denotes a hopper for loading the toner cartridge 431, and toner is supplied from the toner cartridge 431 to the hopper 432 by a required number of agitating rollers 433 arranged in parallel to the axial direction of the photosensitive drum 41. The supplied toner is supplied to the developing roller 434 while stirring.

The paper feed cassette section 5 has, for example, a two-stage configuration, each of which has a paper mounting plate 51 on which recording paper is mounted.
Is removably set from the side. The front end (the right side in FIG. 2) of the sheet placing plate 51 is urged upward by a spring 53 via a support plate 54, and comes into contact with a sheet feed roller 55. The paper feed roller 55 is provided with a separating roller 56 that rotates in the same direction as the paper feed roller 55 so as to prevent double feeding of recording paper. Also,
A recording paper sensor 57 is provided on the main body adjacent to the rear of the paper feed cassette 52, and a magnetic member 58 (see FIG. 2) arranged at the rear end (left side in FIG. A recording paper detecting unit configured to detect a code signal from (3 bits) and detect the size of the recording paper in the paper supply cassette 52 is configured.

The paper transport mechanism 6 feeds out the recording paper stored in the paper feed cassette 52 one by one by a paper feed roller 55 and a separation roller 56, and feeds the fed out recording paper into a transport guide. It is guided by a transport roller 61 provided or by a transport guide plate 62, and is guided to a transfer unit 44 of the image forming unit 4 via a pair of registration rollers 63 driven in synchronization with the start timing of exposure scanning of the scanner unit 3. At the same time, a path is formed for guiding the recording paper after transfer along the conveyance guide plate 64 to a fixing unit 65 having a heat roller 65a and a pressure roller 65b, and further to a discharge tray 67 via a discharge roller pair 66. . Accordingly, when the paper feed roller 54 is driven, the recording paper is transferred to the transfer unit 44 via the registration roller pair 63 by the transfer unit 44.
The toner attached to the surface of the photosensitive drum 41 is transferred,
This toner is fixed in the fixing unit 66.

FIG. 3 is a block diagram showing an example of a control system in the facsimile apparatus. In FIG. 1, a CPU 100 serving as a main control unit includes a memory unit 101 that stores received data in a bus connection manner via a channel.
Are connected to an encoding / decoding unit 102 for encoding and decoding received data so as to be freely input / output. This allows
The encoding / decoding unit 102 encodes the transmission signal from the CPU 100 and transmits it to the NCU 104 via the modem 103, and also decodes the reception signal transmitted from the NCU 104 via the modem 103 and receives it by the CPU 100. It has become.

The encoding / decoding unit 102 can selectively use one for decoding image data using a one-dimensional encoding method (MH) and one for decoding image data using a two-dimensional encoding method (MR). ing. It should be noted that instead of the MR method or M
In addition to the R method, a method of decoding data according to the MMR method in which data whose head line is encoded by the MH method is encoded by the MR method for the number of pages corresponding to the page may be adopted.

The CPU 100 is connected to the scanner unit 3 and transmits image data of the document surface to the light source unit 3.
1 through the CCD 34 and the image processing unit 35. The CPU 100 outputs a signal to the image forming unit 4 via the recording processing unit 105 and outputs a signal to a motor driving unit 106 that drives each roller of the paper transport mechanism 6. As a result, the received data is subjected to image processing of the received document by the recording processing unit 102, and is printed on the recording paper fed by the paper transport mechanism 6 by the image forming unit 4.

The CPU 100 has a method selecting means 107 for selecting an encoding / decoding method in accordance with the resolution of transfer data at the time of high-speed communication, so that the CPU 100 can transmit / receive data to / from the personal computer 108 via RS-232C. It is configured.
As a result, the transfer data from the personal computer 108 is transferred to the CP
The data is transferred to the memory unit 101 under the control of U100, and is sequentially decoded by the decoding method selected by the method selecting unit 107.

Next, an example of the control operation of the above configuration will be described with reference to the flowchart of FIG.

When the facsimile apparatus functions as a printer, it exchanges AT commands and information on each other's capabilities and methods with a personal computer 108, which is an external apparatus for transmitting print images, according to a predetermined procedure. After that, the image data is received from the personal computer 108. When transmitting the information on the performance and the method, the facsimile apparatus indicates that the image data has a decoding capability for the data processed by the one-dimensional coding method (MH). Information indicating that the data has a decoding capability is notified to the data processed by (MR). Here, it is assumed here that the facsimile apparatus has transmitted to the personal computer 108 information indicating that the data processed by the two-dimensional encoding method (MR) can be decoded.
H) and two-dimensional encoding (MR) can be used for data transmission. However, normally, when information indicating that decoding is possible using the two-dimensional encoding (MR) is indicated from the facsimile apparatus, two-dimensional encoding is used. The data which has been subjected to the dimensional encoding (MR) is transmitted.

First, in step S1, the CPU 100
When the AT signal is received from the personal computer 108, in step S2, the width of the start bit of the first data (A) of the AT command sent from the personal computer 100 is detected, and the communication speed is determined.

In step S3, when the resolution set by the personal computer 108 is sent, in step S4, the communication speed is 19200 bps or more, and the resolution set by the personal computer is 16. 0
It is determined whether or not dot / mm × 15.4 line / mm or more. Resolution is 16.0 dots / mm x 1
If it is 5.4 line / mm or more, the process proceeds to step S5, where the decoding system is switched to the one-dimensional coding system (MH), and an instruction signal for transferring image data in the MH coding system is transmitted to the personal computer 108. Then, in step S6, the image data is received by the facsimile procedure and decoded by the one-dimensional coding (MH).

On the other hand, in step S4, the communication speed is 192
00 bps or more and resolution is 16.0 dots / m
YE when smaller than mx 15.4 line / mm
Under conditions other than S, the decoding system is switched to the two-dimensional coding system (MR) in step S7. Then, in step S8, the image data is received by the facsimile procedure and decoded by the two-dimensional encoding method (MR).

When the image data is decoded by one of the one-dimensional coding method (MH) and the two-dimensional coding method (MR), the image data is sequentially printed by the image forming unit 4 in step S9. Is done.

Therefore, according to the above embodiment, when image data is received from a personal computer via RS-232C,
The image data is decoded by the method selecting means 107 by selecting a decoding method according to the resolution. Thus, at the time of high-speed communication, even in the case of a high resolution such as 16.0 × 15.4, that is, even when the decoding process of the CPU 100 takes a long time, the data is decoded by the one-dimensional coding method (MH). , Image data can be reliably received. Further, even if an error occurs in one line of the transfer data, the image abnormality is detected in one line (0.065 m
m), which is too small to be judged by human eyes. Therefore, the performance of the facsimile machine during high-speed communication is significantly improved.

In the above embodiment, the CPU 100
In addition, since only a method selecting means for selecting a decoding method according to the resolution is provided, a device capable of performing high-speed processing in hardware is separately provided, or complicated software is installed. There is no need to build it and it can be easily implemented. Therefore, it leads to cost reduction of the apparatus.

[0030]

As described above, according to the present invention, a decoding unit for selectively decoding image data according to a one-dimensional or two-dimensional coding system, and a coding system according to a data transfer condition. And a selection means for switching the image data, so that it is possible to prevent the occurrence of abnormal image reception without changing the hardware, perform complicated processing by software, and reduce the cost of the apparatus. I can do it.

In addition, when the transmission speed of the transfer data is higher than a predetermined communication speed and the transfer data is higher than a predetermined resolution, the selecting means decodes the data by a one-dimensional coding method (MH). When the resolution is smaller than a predetermined resolution, decoding is performed by the two-dimensional coding method (MR). Therefore, the image reception abnormality is required only for one line, so that there is no practical problem. be able to.

[Brief description of the drawings]

FIG. 1 is a diagram showing an overall configuration of a facsimile apparatus according to one embodiment of the present invention.

FIG. 2 is an internal configuration diagram of the facsimile apparatus.

FIG. 3 is a block diagram showing a control system of the embodiment.

FIG. 4 is a flowchart showing a control operation of the embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 100 CPU 101 Memory part 102 Encoding / decoding part (decoding part) 107 Method selection means (selection means) 108 Personal computer

────────────────────────────────────────────────── ─── Continuing on the front page (72) Shigeaki Nakamura, 1-2-28 Tamazo, Chuo-ku, Osaka-shi Inside Mita Kogyo Co., Ltd. (72) Inventor Hiroshi Sakai 1-2-28, Tamazo-ku, Chuo-ku, Osaka Mita Kogyo Inside (72) Inventor Yukihiro Koi 1-2-2, Tamazo, Chuo-ku, Osaka City Inside Mita Kogyo Co., Ltd. (72) Inventor Tetsuya Nishino 1-2-28, Tamazo, Chuo-ku, Osaka City, Mita Kogyo Co., Ltd. ( 72) Inventor Yoshio Shirai 1-2-28 Tamazo, Chuo-ku, Osaka-shi Mita Kogyo Co., Ltd. (56) References JP-A-7-87332 (JP, A) JP-A-6-98148 (JP, A) JP-A-7-298071 (JP, A) JP-A-6-178122 (JP, A) JP-A-6-125411 (JP, A) JP-A-9-153979 (JP, A) (58) Int.Cl. ⁷ , DB name) H04N 1 / 41-1/419

Claims (1)

(57) [Claims] 1. A facsimile apparatus in which encoded image data transferred from an external device is sequentially decoded and printed, the image data is selectively decoded by first and second encoding methods. And a selector for switching the encoding method according to the conditions of the communication speed and the resolution of the transfer data .
If the communication speed is higher than the predetermined communication speed and the transfer data
Is higher than a predetermined resolution, the one-dimensional encoding method (M
H) When decoding is performed and the resolution is smaller than the predetermined resolution
To decode by two-dimensional coding (MR)
Facsimile apparatus according to claim was that the.