JP2828366B2 - Copier - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying machine, and more particularly to a copying machine for transmitting image information read from a document by a scanner unit through an optical fiber.

[0002]

2. Description of the Related Art In a conventional copying machine, image information obtained by reading a document by a scanner unit is transmitted as an electric signal to an image processing unit via a flat cable or the like. However, when image information is transmitted as an electric signal, noise is generated in the cable itself, or the signal is affected by extraneous noise during transmission through the cable. This is a problem particularly when high image quality is required. This problem can be alleviated by shielding the cable. However, when the cable is shielded, a new problem arises in that the signal deteriorates. This problem becomes more pronounced as the clock frequency increases. In other words, the higher the speed of the scanner, the more
The amount leaked to the shield member increases, and image (density) data in pixel units fluctuates, which affects the image quality of the entire final image. In order to cope with a high-speed scanner without the influence of noise, a method of converting image information read from a document into an optical signal and transmitting the optical signal through an optical fiber has been adopted. In this case, noise does not occur in the cable itself, and there is no influence from external noise. Since the shield is unnecessary, the problem of signal deterioration due to the shield does not occur. In this case, the image information is processed in a configuration as shown in FIG. That is, the light image of the original is first converted into the photoelectric conversion element (CC) of the scanner unit.
D) is converted into an analog electric signal by 42, and A / D
Converter 100 converts the analog signal into a digital signal. Next, the optical signal conversion unit 101 is connected to the A / D converter 10.
The light emitting element 102 is driven based on the digital signal from 0, and an optical signal is transmitted to the optical fiber 10. On the other hand, in the recording unit, the light receiving element 103 receives the optical signal transmitted through the optical fiber 10 and outputs an electric signal corresponding to the optical signal. The image processing unit 104 receives the electric signal and performs predetermined image processing for forming a copy image.
The optical fiber 10 is conventionally laid in a form as shown in FIG. In the figure, 140 is a scanner unit, 4
1 is a lamp reflector assembly. The light emitted from the lamp of the lamp reflector assembly 41 is reflected by a document (not shown), and then reflected by the mirror 43 and the lens 4.
4 leads to the CCD 42 on the CCD substrate 112.
An optical connector 20 is provided outward at the upper end of the substrate 112, and the optical connector 21 attached to the end of the optical fiber 10 is coupled to the connector 20. Then, the optical fiber 10 is laid as shown in FIGS.

[0003]

However, in such a configuration of the optical fiber 10, since the optical fiber 10 draws a large arc, from the left end of the scanner unit 140 to the farthest part of the optical fiber 10 in FIG. However, there is a problem that the distance X1 (FIG. 7) is long and it is difficult to save space.
Specifically, L1 is the width of the scanner unit, L2 is the distance from the scanner unit to the CCD substrate,
Assuming that the height of 0 and 21 is L3, the starting point A of the optical fiber 10 is
Is located at a distance L1 + L2 + L3 from the outside of the CCD substrate 112. In order to solve this problem, as shown in FIG. 8, an optical connector 20 is provided at the lower end of the substrate 112,
By reducing the arc drawn by the optical fiber 10 (R1> R2),
It is also possible to reduce the distance (from X1 to X2).
However, in this case, there is a new problem that the optical signal transmitted through the optical fiber 10 is greatly attenuated as the optical fiber 10 is strongly bent. SUMMARY OF THE INVENTION It is an object of the present invention to provide a copying machine that transmits image information by using an optical fiber that saves space without attenuating a transmission signal.

[0004]

According to the present invention, there is provided a scanner unit for optically reading a document, and a guide unit for transmitting image information read by the scanner unit while being curved from the inside of the scanner unit to the outside in one direction. And an optical fiber arranged to be guided while being curved in a direction opposite to the one direction.

[0005]

In the copying machine according to the present invention, the optical fiber is arranged so as to be guided while being curved from the inside of the scanner unit to one direction to the outside, and then guided while being curved in the direction opposite to the one direction. I have. Therefore, the distance between the farthest part of the arc drawn by the optical fiber and the end of the scanner unit can be shortened as compared with the case where the optical fiber is bent in a direction reversed outside the scanner unit.
As a result, transmission loss of an optical signal caused by sharply bending the optical fiber does not occur, and space saving of the scanner unit of the copying machine can be realized.

[0006]

Next, an embodiment of the present invention will be described with reference to the drawings. Here, a digital copying machine will be described as an example of the copying machine of the present invention. FIG. 4 is a sectional view showing the entire configuration. As shown in FIG. 4, the digital copying machine 30 includes a scanner unit 31 and a laser printer unit 3.
2. A multi-stage paper feed unit 33 and a sorter 34 are provided. The scanner unit 31 includes a document table 35 made of transparent glass, and an automatic document feeder (RDF) 36 for both sides.
And a scanner unit 40. The multi-stage paper feed unit 33 has a first cassette 51, a second cassette 52, a third cassette 53, and a fourth cassette 55 that can be added by selection. Multi-stage paper feed unit 3
At 3, the sheets stored in the cassettes of each stage are sent out one by one from the top and conveyed to the laser printer unit 32. The RDF 36 sets a plurality of documents at once, automatically feeds the documents one by one to the scanner unit 40, and causes the scanner unit 40 to read one or both sides of the document according to the operator's selection. It is configured as follows. The scanner unit 40 includes a lamp reflector assembly 41 for exposing the original, a plurality of reflection mirrors 43 for guiding a reflected light image from the original to a photoelectric conversion element (CCD) 42, and a CCD 4 for reflecting the reflected light image from the original.
2 includes a lens 44 for imaging. When scanning a document placed on the document table 35, the scanner unit 31 is configured to read a document image while the scanner unit 40 moves along the lower surface of the document table 35. If you use RDF
The document image is read while the document is being conveyed while the scanner unit 40 is stopped at a predetermined position below the document 36. The image data obtained by reading the original image by the scanner unit 40 is sent to an image processing unit (not shown), which will be described later, and is subjected to various processes. In response, the image data in the memory is supplied to the laser printer unit 32 to form an image on a sheet. The laser printer unit 32 includes a manual document tray 45, a laser writing unit 46, and an electrophotographic processing unit 47 for forming an image. The laser writing unit 46 includes a semiconductor laser that emits a laser beam corresponding to the image data from the memory described above, a polygon mirror that deflects the laser beam at a constant angular velocity,
The laser beam deflected at a constant angular velocity is applied to the electrostatic photographic processing unit 47.
And an f-θ lens that corrects so as to be deflected at a constant speed on the photosensitive drum 48. The electrophotographic process unit 47 includes a charging unit, a developing unit, a transfer unit, a peeling unit, a cleaning unit, a static eliminator, and a fixing unit 49 arranged around a photoreceptor drum 48 in a known manner. A transport path 50 is provided downstream of the fixing device 49 in the transport direction of the sheet on which an image is to be formed. The transport path 50 communicates with a transport path 57 leading to the sorter 34 and the multi-stage paper feed unit 33. It branches into a transport path 58. The transport path 58 is branched in the multi-stage paper feed unit 33, and a reverse transport path 50a and a double-sided / combined transport path 50b are provided as transport paths after branching. The reversing conveyance path 50a is a conveyance path for reversing the front and back of a sheet in a duplex copying mode for copying both sides of a document. Double-sided / Synthetic conveyance path 50b
Is a single-sided composite copy in which a sheet is transported from the reverse transport path 50a to the image forming position of the photosensitive drum 48 in the double-sided copy mode or a composite copy is performed on one side of the sheet to form an image of a different document or an image with toner of a different color. This is a conveyance path for conveying the sheet to the image forming position of the photosensitive drum 48 without reversing the sheet in the mode. Multi-stage paper feed unit 33
Includes a common transport path 56, and the common transport path 56 is a first transport path.
The paper from the cassette 51, the second cassette 52, and the third cassette 53 is carried out toward the electrophotographic processing unit 47. The common transport path 56 joins with the transport path 59 from the fourth cassette 55 on the way to the electrophotographic process section 47 and communicates with the transport path 60. The conveyance path 60 merges with the double-sided / combined conveyance path 50b and the conveyance path 61 from the manual document tray 45 at a junction 62 to an image forming position between the photosensitive drum 48 of the electrostatic photographic processing unit 47 and the transfer unit. The three transfer paths are provided at a junction 62 near the image forming position. Therefore, the laser writing unit 46
In the electrophotographic processing unit 47, the image data read from the above-described memory is formed as an electrostatic latent image on the surface of the photosensitive drum 48 by scanning a laser beam by the laser writing unit 46, and is formed by toner. The visualized toner image is transferred to the multi-stage paper feed unit 3
The image is electrostatically transferred and fixed on the surface of the sheet conveyed from No. 3. The paper on which the image is formed in this manner is supplied to the fixing device 49.
Is transported to the sorter 34 via the transport paths 50 and 57, or is transported to the reverse transport path 50a via the transport paths 50 and 58. Next, the configuration and functions of the image processing unit included in the digital copying machine 30 will be described. FIG. 5 is a block diagram of the image processing unit included in FIG. The image processing units included in the digital copying machine 30 include an image data input unit 70, an image processing unit 71, and an image data output unit 7.
2. A memory 73 including a RAM (random access memory) and a central processing unit (CPU) 74 are provided. The image data input section 70 includes a CCD section 70a, a histogram processing section 70b, and an error diffusion processing section 70c. The image data input unit 70 is a CCD 42 shown in FIG.
The image data of the original read from
While taking a histogram as a binary digital quantity,
The image data is processed by the error diffusion method and is temporarily stored in the memory 73. That is, CCD
In the unit 70a, after an analog electric signal corresponding to each pixel density of the image data is A / D converted, MTF correction, monochrome correction or gamma correction is performed, and 256 gradations (8 bits)
To the histogram processing unit 70b. In the histogram processing unit 70b, the CCD unit 7
The digital signal output from 0a is added for each pixel density of 256 gradations to obtain density information (histogram data), and if necessary, the obtained histogram data is sent to the CPU 74 or error diffusion is performed as pixel data. It is sent to the processing unit 70c. Error diffusion processing unit 70c
According to the error diffusion method, which is a kind of pseudo halftone processing, that is, a method in which a binarization error is reflected in the binarization determination of an adjacent pixel, the 8-bit / pixel digital signal output from the CCD unit 70a is converted to 1 bit. It is converted to bits (binary), and a redistribution operation is performed to faithfully reproduce the local area density in the document. The image processing unit 71 is a multi-value processing unit 71
a, 71b, synthesis processing section 71c, density conversion processing section 71
d, a scaling unit 71e, an image processing unit 71f, an error diffusion processing unit 71g, and a compression processing unit 71h. The image processing unit 71 is a processing unit that finally converts the input image data into image data desired by the operator, and is processed by the processing unit until it is stored in the memory 73 as the finally converted output image data. It is configured to process. However, the above-described processing units included in the multi-image processing unit 71 function as needed, and may not function. That is, the multi-value processing section 71a,
At 71b, the data binarized by the error diffusion processing unit 70c is converted again into 256 gradations. The synthesis processing unit 71c selectively performs a logical operation for each pixel, that is, a logical sum, a logical product, or an exclusive logical sum. The data to be subjected to this calculation is the image data stored in the memory 73 and the bit data from the pattern generator (PG). In the density conversion processing unit 71d, 25
The relationship between the input density and the output density is arbitrarily set based on a predetermined tone conversion table with respect to the digital signals of 6 tones. The scaling unit 71e calculates the pixel data (density value) for the target pixel after scaling by performing an interpolation process based on the input known data in accordance with the designated scaling factor. After the multiplication, the main scanning is scaled. In the image processing unit 71f, various image processes are performed on the input pixel data, and information collection such as feature extraction may be performed on a data sequence. The error diffusion processing unit 71g includes an image data input unit 70
The same processing as the error diffusion processing unit 70c is performed. The compression processing unit 71h performs 2
The value data is compressed. As for the compression of image data, the compression functions in the final processing loop when the final output image data is completed. The image data output unit 72 includes a restoration unit 72a, a multi-value processing unit 72b, an error diffusion processing unit 72c, and a laser output unit 72d. The image data output unit 72 restores the image data stored in the memory 73 in a compressed state, converts the image data back into the original 256 gradations, and generates an error in the quaternary data that provides a smoother halftone expression than the binary data. It is configured to perform diffusion and transfer data to the laser output unit 72d. That is, in the restoration unit 72a, the image data compressed by the compression processing unit 71 is restored. The multi-value processing section 72b performs the same processing as the multi-value processing sections 71a and 71b of the image processing section 71. The error diffusion processing unit 72c performs the same processing as the error diffusion processing unit 70c of the image data input unit 70. In the laser output section 72d, digital pixel data is converted into a laser on / off signal based on a control signal from a sequence controller (not shown), and the laser is turned on / off. The data handled by the image data input unit 70 and the image data output unit 72 is basically stored in the memory 73 in the form of binary data in order to reduce the capacity of the memory 73. It is also possible to process in the form of quaternary data in consideration of deterioration. Next, the scanner unit 31 according to the embodiment of the present invention will be described in more detail with reference to FIG. In addition,
FIG. 3 is a cross-sectional view showing the scanner unit 31 of FIG. 4 as viewed from the back side of the paper surface of FIG. The scanner unit 40 is attached to a guide shaft 11 provided in the optical unit 1 and has a structure movable along the guide shaft 11 right and left in the drawing. A wire take-up pulley 7 is provided at the left end of the optical unit 1, and an idle pulley 9 is provided at the right end. A drive wire 8 is stretched between these pulleys 7, 9. And
One end of the drive wire 8 is directly fixed to the scanner unit 40, and the other end is fixed to the scanner unit 40 through a predetermined spring.

In the figure, a scanner unit 40 indicated by a dotted line
Indicates a state in which the scanner unit 40 has moved to the rightmost position. In this state, as the distance from the right end of the scanner unit 40 to the farthest part of the optical fiber 10 becomes shorter, the useless space between the right end of the optical unit 1 and the right end of the scanner unit 40 can be eliminated. Next, the scanner unit 40 will be described in detail. FIG. 1 is a side sectional view showing the scanner unit 40, and FIG. 2 is a plan sectional view showing a portion below the lamp reflector assembly 41 of the scanner unit 40. In the figure, the same components as those of the scanner unit of FIG. 7 are denoted by the same reference numerals.

The mirror 43 emits the lamp of the lamp reflector assembly 41 and is arranged to guide the light reflected by the original on the original table 36 to the CCD 42.
The light reflected by the mirror 43 enters the CCD 42 on the CCD substrate 12 through the lens 44. The plurality of optical connectors 20 are provided inward at the lower end of the substrate 12 and on the surface of the scanner unit 40 on the main body side. An optical connector 21 is attached to an end of each optical fiber 10 for transmitting image information from the CCD 42 to the image processing unit, and each optical fiber 10 is connected to the corresponding optical connector 20 by the optical connector 21. Substrate 12
The optical fiber 10 connected to is formed in a loop as shown in FIG. That is, the optical fiber 1
In the scanner unit 40, 0 is first turned in a direction (from left to right in FIG. 3) while drawing an arc while being curved, and is guided to the outside from the upper end of the scanner unit 40. Thereafter, the light is curved and reversed outside the scanner unit 40 in a direction opposite to one direction (from right to left in FIG. 3), and is guided to the left end side of the optical unit 1. An embodiment of the present invention will be described in more detail as compared with a conventional example. As described above, in the conventional example, the starting point A of the optical fiber is separated from the left end of the scanner unit by a distance of L1 + L2 + L3. On the other hand, in the embodiment of the present invention, the starting point B of the optical fiber 10 comes inward by L3 from the CCD substrate 12 toward the scanner unit. That is, the starting point B of the optical fiber is L1 + L2-L3. Therefore,
When the loop of the optical fiber 10 is formed while drawing the same arc of R1 as in the conventional example, the distance X3 from the left end of the scanner unit 40 to the farthest part of the optical fiber 10 (X1 in the conventional example).
) Is considerably shorter. That is, the closer the optical fiber start point B is to the inside of the scanner unit 40, the fewer arc portions of the optical fiber 10 exposed from the scanner unit 40. As described above, in the copying machine of the present embodiment, the connectors 20 and 21 on the scanner unit side for connecting the optical fiber 10 to the scanner unit 40.
Is provided on the back side of the substrate 12, and its position is inside the end of the scanner unit 40, and the distance X3 from the end of the scanner unit 40 to the farthest part of the optical fiber 10 can be shortened. 1 can be saved.

[0009]

In the copying machine of the present invention, the optical fiber is arranged so as to be guided from the inside of the scanner unit in one direction to the outside while being curved and then guided in the direction opposite to the one direction. Have been. Therefore, the distance between the farthest part of the arc drawn by the optical fiber and the end of the scanner unit can be shortened as compared with the case where the optical fiber is bent in a direction reversed outside the scanner unit. As a result, transmission loss of an optical signal caused by sharply bending the optical fiber does not occur, and space saving of the scanner unit of the copying machine can be realized.

[Brief description of the drawings]

FIG. 1 is a sectional view showing a part of a scanner unit of a copying machine according to an embodiment of the present invention.

FIG. 2 is a plan view showing a portion of the scanner unit of FIG.

FIG. 3 is a sectional view showing a scanner unit including a portion of the scanner unit of FIG. 1;

FIG. 4 is a cross-sectional view showing the entire copying machine including the scanner unit of FIG. 3;

FIG. 5 is a block diagram illustrating an image processing unit of the copying machine of FIG. 4;

FIG. 6 is a block diagram showing a signal processing unit of a conventional copying machine.

FIG. 7 is a cross-sectional view showing a scanner unit of a conventional copier.

FIG. 8 is another sectional view showing a scanner unit of a conventional copier.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 Optical fiber 12 CCD board 20, 21 Optical connector 30 Digital copying machine 40 Scanner unit 42 Photoelectric conversion element

Claims (1)

(57) [Claims] A scanner unit for optically reading an original; and a scanner unit for guiding image information read by the scanner unit from an inside of the scanner unit to a direction to an outside to transmit the image information. And an optical fiber arranged to be guided while being curved in a direction opposite to the direction.