JPH0416837A - Image forming device - Google Patents

Abstract

PURPOSE:To reduce the size of the image forming device by arranging a width indicating means which indicates the maximum width of image formation and a reference plate for color correction opposite to an original receiving member in plane. CONSTITUTION:The width indicating means 54 which indicates the maximum width of image formation and the reference plate 56 for color correction are arranged adjacently to the original receiving member 2 in plane. Pointers 51 and 52 of the width indicating means 54 are supported by a couple of belts 57a and 57b, which are driven by a driving part including a motor in directions Y1 and Y2 according to form size and image magnification to vary the interval between both the pointers 51 and 52. Consequently, an original mounting means 55 is made thin and the device itself is reducible in size.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Field of Application) The present invention relates to an image forming apparatus, and more particularly, to an original document placing means for placing an original document on a document table for image formation. The present invention relates to an improvement of an image forming apparatus equipped with the above-mentioned image forming apparatus.

(Prior Art) Conventionally, in an image forming apparatus such as a copying machine, a color correction device is used to form an image on the lower side of a document receiving member with a document scale that displays the paper size (width size) of various documents. Many of them are equipped with a reference plate (shading reference plate), but there is also a width indicating means (indicator) that indicates the image forming width based on the image magnification and the paper feed cassette installed in this image forming apparatus.
With such a configuration, when you try to copy a certain area of a document, depending on the set image magnification and the width of the paper in the paper cassette, the copied image may not be printed on the paper. It is not possible to know immediately whether to cut or not,
For this reason, there is a complication in that it is necessary to conduct a trial scan of the original to determine whether the paper is suitable or not.

Further, as shown in FIG. 5, a device having a width indicating means 63 provided below the document table 61 and the document receiving member 62 is also known.

However, in the case of this width indicating means 63, a pair of pointers 64a
, 64b extend further along the document table 61 from the contact portion 62a of the document receiving member 62 with the document 0 on the lower side of the document table 61. A certain amount of space is required between the image forming apparatus and the carriage 65 as a system, resulting in a problem that the image forming apparatus becomes larger.

(Problems to be Solved by the Invention) As described above, in the conventional apparatus, there is a problem in that the image forming possible width cannot be recognized, or even if it can be recognized, the size of the apparatus itself is increased.

SUMMARY OF THE INVENTION Therefore, it is an object of the present invention to provide an image forming apparatus that allows the size of the apparatus itself to be reduced and allows easy recognition of the image forming width.

[Structure of the Invention (Means for Solving the Problems)] The present invention provides an arrangement in which a document receiving member with a document scale is disposed along an edge region of a document table, and a document serving for image formation is provided at the end of the document receiving member. In an image forming apparatus, the image forming apparatus is equipped with a document placing means that is brought into contact with an edge of the original document receiving member, and a width indicating means that indicates a possible image forming width that is exposed on the upper surface side of the document receiving member; A reference plate for color correction is arranged adjacent to the document receiving member in a plane.

The reference plate may be arranged between an end of the document receiving member and the width indicating means.

(Function) According to the image forming apparatus having the above configuration, since the width indicating means and the reference plate are arranged adjacent to the document receiving member in a plane, the thickness of the document placing means can be reduced. be able to.

Further, the width indicating means is exposed on the upper surface side of the document receiving member and is used for recognizing the image forming possible width.

(Example) The present invention will be explained in detail below.

FIG. 1 shows, as an example of the image forming apparatus of this embodiment, a thermal transfer type color copying machine that can selectively produce multicolor copies. In other words, 1 is the copying machine main body,
An operation panel (not shown) is provided at the front of the upper surface of the copying machine main body 1 .

The upper part of the copying machine main body 1 is provided with a document scanning section 3 for scanning and reading a document ○ set on a document table (transparent glass) 2, and the lower part thereof is an image forming section 4. still,
Reference numeral 5 denotes a document cover provided on the document table 2 so as to be openable and closable. Further, the document table 2 is fixed to the main body 1 of the copying machine.

At one end of the document table 2 in the longitudinal direction, as shown in FIG.
), as shown enlarged in (b), A3. A4. Fixed scale 5 with letters such as A5
A document receiving member 53 with a 0 mark, a white reference plate (shading reference plate) 56 for color correction during image formation, and a width indicating means 54 having pointers 51 and 52 indicating the image forming possible width.
In other words, the reference plate 569 and the width indicating means 54 are arranged adjacent to the document receiving member 53 in a plane.

The document table 2. Original receiving member 53. The reference plate 56 and the width indicating means 54 constitute a document placing means 55.

As shown in FIGS. 2(a) and 2(b), the document receiving member 53 includes a transparent portion 53a having a constant width along the width direction (Y+, Y2 direction) of the document table 2. As shown in FIGS.

The width indicating means 54 includes a pair of pointers 51 and 52 located on the sides of the end of the document table 2 and facing below the transparent portion 53a of the document receiving member 53.

The pointers 51, 52 have a pair of healds 57a.

57b, and both belts 57a and 57b are driven by a drive unit including a motor (not shown) in the Y and Y2 directions, respectively, depending on the paper size and image magnification, thereby adjusting the distance between the pointers 51 and 52. It's starting to change.

The width in the Y direction and the Y2 direction is the range between the previous guideline 51 and 52, or the copyable range.

Further, the reference plate 56 is provided on the upper surface of the end of the document table 2 below the fixed scale 50.

The document scanning section 3 is configured as shown in FIG. 1, for example. That is, the first carriage 7 is equipped with an illumination lamp as a light source, the second carriage 8 bends the optical path with a mirror, the lens 9 guides the reflected light from the original O to a photoelectric converter 11 (described later), and the optical path length is changed when changing the magnification. The mirror part 10 is configured by a photoelectric converter (converting means) 11 that receives reflected light from the original O, and a drive system (not shown) that changes the positions of these parts.

The first carriage 7 includes an illumination lamp 6 that irradiates light onto the document O, a glue deflector 12 that serves as a reflector that collects the light from the illumination lamp 6 onto the surface of the document, and a second carriage that directs the reflected light from the document 0. A mirror 13 that guides the camera to the 8 side is mounted.

The second carriage 8 is equipped with mirrors 8a and 8b that guide the light guided by the mirror 13 to the lens 9. Above 1. The second carriages 7.8 are connected to each other by a timing belt (not shown), so that the second carriage 8 moves at 1/2 the speed of the first carriage 7 in the same direction. This makes it possible to scan so that the optical path length up to the lens 9 is constant.

The lens 9 has a fixed focal length and is moved in the optical axis direction when changing the magnification. Alternatively, a variable focal length lens such as a zoom lens may be used.

The mirror part 10 includes two mirrors 10a.

10b, and those mirrors 10a according to the change in optical path length corresponding to the selected magnification ratio.

The position of the lens 10b changes, and the light from the lens 9 is guided to the photoelectric converter 11 by bending the optical path with the two mirrors 10a and 10b.

The photoelectric converter 11 photoelectrically converts the reflected light from the original 0, thereby converting the image of the original O into C (cyan), G (green), Y (yellow), R (red), G (green), It separates and outputs B (blue) light as a color signal, and is mainly composed of, for example, a CCDCD beline image sensor. In this case, one pixel of document ○ is CC
Three consecutive elements of the D sensor (C, G, Y or R
,G.

It corresponds to B). The output of the photoelectric converter 11 is output to an A/D converter 91, which will be described later.

Said 1st. 2nd carriage 7.8, lens 9, mirror 1
Movement of 0a and 10b is carried out by stepping motors (
(not shown).

The mirrors 10a, 10b and lens 9 are each moved by separate stepping motors (not shown). A spiral shaft (not shown) is rotated by a corresponding stepping motor, and the lens 9 is moved in the optical axis direction by this spiral movement.

The image forming section 4 is configured as shown in FIG. 1, for example. That is, the platen drum 22 is disposed approximately at the center of the image forming section 4 .

The platen drum 22 has a periphery made of an elastic material such as rubber, and functions as a platen roller for the thermal head 24. The platen drum '22 itself rotates counterclockwise to wrap the paper P around its outer periphery to prevent the paper P from shifting during overlapping printing. Pressure rollers 25 are arranged around the platen drum 22 at predetermined intervals to prevent the paper P from floating up from the platen drum 22. ...is provided. The circumferential length of the platen drum 22 is slightly longer than the length in the longitudinal direction of the maximum paper size.

A thermal head 24 is disposed diagonally below and to the left of the platen drum 22 . The thermal head 24 is attached to a heat radiator integrally formed on the rear end surface of the holder. An ink ribbon 26 is interposed between the platen drum 22 and the thermal head 24.

The cores 30 and 31 of the ink ribbon 26 are connected to a drive shaft of a motor (not shown) via a drive force transmission mechanism (not shown), and are driven to rotate as required.

A paper feed roller 41 is provided at a lower portion of the copying machine main body 1, and is configured to take out sheets of paper P as an image forming medium stored in the paper feed cassette 20 one by one. The paper P taken out by the paper feed roller 41 is transported by a transport roller 42 toward the platen drum 22 located diagonally above and to the left of the transport roller 42, and then transferred to the gripper 23.
Pressure roller 25. ... brings it into a state where it is wound around the platen drum 22, and is thereby accurately fed.

Here, the paper feed cassette 20 is detachable from the side of the copying machine main body 1. In addition, 46 in FIG. 1 is paper P.
This is a manual paper feeding device for manually feeding paper such as paper. The paper P fed from the manual paper feeder 46 is also wound around the platen drum 22 in the same manner as described above.

The paper P, whose leading end is fixed by the gripper 23, is wound around the platen drum 22 by counterclockwise rotation, and after the leading end passes through the printing area, it is transferred to the thermal head 24.
is pressed against the platen drum 22, and printing is performed.

When printing of the first color is completed, the platen drum 22 rotates approximately once. Here, the thermal head 24 is once released, the ink ribbon 26 is wound up, and the next color is located.

Then, the platen drum 22 starts rotating clockwise, printing is performed by the thermal head 24, and the next color is overprinted (printed).

In this way, in the case of full-color copying, image formation is performed by four operations of yellow, magenta, cyan, and black, or three operations of yellow, magenta, and cyan.

In the case of a single color such as black, it is performed in one operation.

When discharging the paper, the platen drum 22 is rotated counterclockwise until the trailing edge of the paper P reaches the paper discharging guide 27, and when the rear end of the paper P reaches the paper discharge guide 27, the platen drum 22 is rotated clockwise. A separation claw (not shown) separates the rear end of the paper P from the platen drum 22 and guides it to the paper discharge guide 27. Finally, the leading edge of the paper P is released from the gripper 23, and the paper P, which has been copied and transported by the paper discharge guide 27, is discharged onto the paper discharge tray 28.

FIG. 3 schematically shows the overall control system, in which the main control section 81. It has a first sub-control section 82 and a second sub-control section 83. The main control unit 81 includes an operation panel 80. memory 9
9. Correction circuit 84. Luminance color difference separation circuit 855 Image quality improvement circuit 869 Color signal conversion circuit 87. Binarization circuit 88. connected to the first sub-control unit 82 and the second sub-control unit 83, respectively,
In charge of these controls.

The first sub-control unit 82 includes a light source control unit 89. Motor drive section 90. The photoelectric converter 11. It is connected to an A/D converter 91 and a resolution converter 92, respectively, and controls these. The light source control unit 89 is connected to the illumination lamp 6,
Controls the lighting and light amount. That is, the illumination lamp 6 is turned on during a normal image reading operation.

The motor drive section 90 drives the scanning motor 18.

The second sub-control unit 83 includes a thermal head temperature control unit 93,
It is connected to the thermal head 24, various detection switches 94, and drive section 95, and controls these. The drive unit 95 is connected to a drive system 96 such as a motor and a solenoid, and drives the drive system 96 .

The memory 99 converts the light reflected by the reference plate 59 into A/
It stores the D-converted reference data.

The correction circuit 84 performs standardization (shading correction, that is, variation correction of the photoelectric converter 11 ).

Next, the color signal conversion circuit 87 will be explained in more detail with reference to FIG. The luminance signal (■) sent from the image quality improvement circuit 86, the color difference signal (CI), and the color difference signal (C
Each signal of 2) is sent to the color signal conversion circuit 87,
Here Y, M, C.

Either one of the color signals of B is sent to the binarization circuit 88 as the signal X, Y, M.

The selection of C and B color signals is performed by the main control section 81. That is, as shown in the table below, the main control unit 81 determines Y, which is sent to the binarization circuit 88, based on the combination of signals a and b.
Select M, C, and H color signals. Note that the color signals are automatically selected sequentially (for example, Y-4-M-4-
C-B order).

Next, the operation in the above configuration will be explained. For example, the operator now specifies copying conditions such as magnification using the operation panel 80. Then, the main control unit 81 controls the paper feed cassette 2.
The copyable range (width in the Y and Y2 directions) is determined based on the size of the paper P within 0, the copy magnification, etc., and the driving section is driven according to the result of this determination. As a result, the guideline 51.5
2 is moved, and the copyable range determined by the specified copying conditions and the size of paper P is indicated on the transparent portion 53a of the document receiving member 53.

In response to this instruction, the operator places the original O and presses a copy start key (not shown). Then, the main control section 81 drives the drive section to move the pointer 51.degree. 52 to a position equal to or larger than the maximum document width (for example, 297 mm for A3 size), that is, to a non-image area.

In addition, the main control unit 81 lights up the illumination lamp 6, and also lights up the first illumination lamp 6. Move the second carriage 7.8. As a result, the light from the illumination lamp 6 passes through the document table 2 to the reference plate 56.
and irradiates the original O.

The reflected light from the reference plate 56 and the original O is reflected by the mirror 1.
3, 8 a, 8bs Lens 9, Mirror 10a, 10b
are guided to the photoelectric converter 11 via the . Photoelectric converter 1
1 makes that light cyan (C).

The signal is separated into analog color signals of green (G), yellow (Y), red (R), green (G), and blue (B), and sent to the A/D converter 91.

The A/D converter 91 converts each analog color signal into a digital signal.

The signal from the reference plate 56 from the A/D converter 91 is stored in the memory 99 as reference data.

Then, the signal of the original O from the A/D converter 91 is output to the resolution converter 92.

The resolution conversion unit 92 performs resolution conversion to match the resolution of the photoelectric converter 11 and the resolution of the thermal head 24, and sends the result to the correction circuit 84. Photoelectric converter 11
This can be omitted if the resolutions of the thermal head 24 and the resolution of the thermal head 24 are the same. The correction circuit 84 normalizes the C, G, Y or R, G, B color signals sent from the resolution converter 92 using the reference data stored in the memory 99, and performs photoelectric conversion. A correction process (shading correction) is performed in order to correct variations in the brightness and color difference separation circuit 85 . The luminance color difference separation circuit 85 receives C, G, Y or R, G, sent from the correction circuit 84.
Various calculation processes are performed on each color signal of B, and the luminance signal (
(2) Separate into 9 color difference signals (C1) and 9 color difference signals (C2) and send them to the image quality improvement circuit 86. The image quality improvement circuit 86 receives the luminance signal (I) sent from the luminance color difference signal circuit 85.
)9 The color difference signal (C1) and color difference signal (C2) are analyzed, image quality improvement processing such as edge emphasis and single character identification are performed, and the results are sent to the color signal conversion circuit 87.

The color signal conversion circuit 87 performs color conversion based on the luminance signal (■), color difference signal (C1), and color difference signal (C2) that have been subjected to image quality improvement processing to produce yellow (Y).

Converts to one color signal (signal corresponding to density) of magenta (M), cyan (C), black (B) [the three primary colors (Y, M, C) plus B during printing] and converts it into a binary signal. circuit 8
Send to 8. The binarization circuit 88 receives the color signal (Y.

M, C, B) is subjected to area gradation conversion, that is, binarization, using a dither method or the like, and the binarized signal is sent to the thermal head temperature control section 93. The thermal head temperature control section 93 sends a print signal to the thermal head 24 based on the binarized signal supplied from the binarization circuit 88 .

Further, in response to the input of the copy start key (not shown), the paper P in the paper feed cassette 20 is taken out by the paper feed roller 41, and the taken out paper P is transported by the transport roller 42.

Then, the conveyed paper P is guided to the platen drum 22 via the guide 43, and its leading end is fixed by the gripper 23. As a result, the paper P is transferred to the platen drum 22.
is wrapped around.

Depending on such a state, the thermal head 24:
Printing (that is, image formation) is performed on the paper P wound around the platen drum 22 in accordance with the print signal.

When the printing is finished, the main control section 81 turns off the illumination lamp 6, discharges the paper P wrapped around the platen tram 22, and finishes the copying operation.

In addition to the embodiments described above, the present invention can be modified in various ways within the scope of its gist.

[Effects of the Invention] According to the present invention described in detail above, with the above-described configuration, the width indicating means and the reference plate are adjacent to the document receiving member in a two-dimensional manner. It is possible to provide an image forming apparatus that can be made thinner and smaller in size, and in which the width indicating means is exposed on the upper surface side of the document receiving member, so that the image forming possible width can be easily recognized.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a color copying machine as an embodiment of the present invention, FIG. 2(a) is an enlarged cutaway plan view of the original document mounting means, and FIG. 2(b) is an enlarged cutaway sectional view of the same. 3 is a block diagram showing the control system of the same as above, FIG. 4 is a block diagram for explaining the operation of the color signal conversion circuit of the above, and FIG. 5 is an enlarged cutaway sectional view of a conventional document placement means. 1... Copying machine main body, 2... Original table, 53.
...Document receiving member, 54...Width indicating means, 55...
- Original mounting means, 56... reference plate. (b)

Claims (2)

[Claims] (1) A document receiving member with a document scale is disposed along the edge area of the document table, and includes document placing means such that the end of the document to be subjected to image formation is brought into contact with the edge of the document receiving member. In the image forming apparatus, width indicating means for indicating a possible image forming width exposed on the upper surface side of the document receiving member, and a reference plate for color correction for performing image formation are provided in a plane with respect to the document receiving member. An image forming apparatus characterized in that the image forming apparatus is arranged adjacent to the image forming apparatus. (2) The image forming apparatus according to claim 1, wherein the reference plate is arranged between an end of the document receiving member and the width indicating means.