JPH0422978A - Copying device - Google Patents

Abstract

PURPOSE:To surely prevent a recording paper from winding to a fixing roller by controlling an erasing means according to a copying mode such as monochrome copying and color copying so that the void part of a specified width may be formed on the leading edge part of the recording paper. CONSTITUTION:An eraser 8 is disposed on the rotational orbit of a photosensitive body 2 and it destaticizes the corresponding part of the photosensitive body 2 so that the void part of the specified width may be formed on the leading edge part of the recording paper. Since the driving of the eraser 8 is controlled according to the copying mode, the void part of the width corresponding to the copying mode such as the monochrome copying and the color copying is formed on the recording paper. Thus, the recording paper is surely prevented from winding to the fixing roller 51.

Description

Detailed Description of the Invention [Field of Industrial Application] The present invention relates to a copying apparatus capable of selecting a copy mode between monochrome copying and color copying, and in particular, to Use a copying machine that can prevent wrapping.

[Conventional technology]

Generally, in a copying machine, a latent image of an original image formed on the surface of a photoreceptor is converted into an image using toner, this toner image is transferred to recording paper, and then the toner image is fused and fixed onto the recording paper by a heated fixing roller. is making copies. During this copying process, toner from the recording paper may remain attached to the fixing roller, and this toner may cause the subsequently supplied recording paper to wrap around the fixing roller, causing a paper jam and interrupting the operation. In order to prevent such wrapping around the fixing roller, a copying apparatus as disclosed in Japanese Patent Publication No. 54-36502 has been proposed.

This conventional copying device prevents charging of the surface of the photoconductor corresponding to the leading edge of the recording paper by providing a white light-shielding portion at a reference position on the document table corresponding to the leading edge of the recording paper, and records data in this state. The toner image is transferred to paper and then thermally fixed by a fixing roller.

As a result, toner is not transferred to the leading edge of the recording paper, so toner does not adhere to the corresponding fixing roller, and the leading edge of the recording paper passes smoothly through the fixing roller without getting wrapped around it. can do.

[Problem to be solved by the invention]

By the way, the white areas in a monochrome copy and the white areas in a color copy are necessarily different in width. This is because the white areas in monochrome copies are approximately 1 to 2 rm wide, whereas in color copies, images are formed by overlapping toners of three colors: Y (yellow), M < magenta), and C (cyan). This is because it is necessary to maintain good releasability between the recording paper and the fixing roller, and the width is about 5 mm.

However, in the above-mentioned conventional copying apparatus, the width of the blank area is uniquely determined by the width of the white light-shielding portion of the document table, and therefore, the width of the blank area can only be changed. For this reason, in a copying device that allows the copy mode to be switched or selected between monochrome copying and color copying, if the width of the white light-shielding area is set to match monochrome copying, the white areas will be smaller than the copy width and will be recorded during color copying. There is an inconvenience that the paper gets wrapped around the fixing roller.On the other hand, if the width of the white light-shielding area is set to match the color copy, the width of the white area will be larger, creating a different texture when copying in black and white.
There is an inconvenience that part of the original image is missing. Therefore, it is an object of the present invention to solve such problems.

[Means to solve the problem]

In order to solve the above problems, the present invention provides an operating means for selecting a copy mode of monochrome copying and color copying, and forming an original image on the surface of a photoreceptor, transferring this image to recording paper and switching to the copy mode. Copying means for developing a corresponding visible image; and a blank area of a predetermined width is formed at the leading edge of the recording paper by erasing the image on the surface of the photoreceptor corresponding to the leading edge of the recording paper. The apparatus is configured to include an erasing means for making an image part, and a control means for driving the erasing means so that the white part of the recording paper has a width corresponding to the selected copy mode. be.

[For production]

According to a copying apparatus having such a configuration, the drive of the erasing means that forms a non-image area on the surface of the photoreceptor is controlled according to the copy mode, so that it can be used for both monochrome copying and color copying. It is possible to print a blank copy of the width corresponding to the copy mode on recording paper, and
Wrapping around the fixing roller can be reliably prevented.

〔Example〕

Embodiments of the present invention will be described below based on the drawings. 1 to 4 are diagrams showing an embodiment of a copying apparatus according to the present invention.

FIG. M1 is a side view showing the internal structure of the copying apparatus in which copy modes of monochrome copying and color copying can be selected, and FIG. 2 is a block diagram for controlling the copying apparatus. As shown in FIG. 1, an optical system 1 that reads an original image by light irradiation, a drum-shaped photoreceptor 2 on which a latent image of the read original image is formed, and an optical system disposed around the photoreceptor 2. The developing device 3 that develops the latent image with toner includes 3c and 3.
m3y, a transfer section 4 to which the developed toner image is transferred, and a fixing section 5 that heats and fixes the recording paper from the transfer section 4, forming a copying means.

The optical system 1 is disposed below a contact crow 6 that serves as a document table, and forms a light source 11 that irradiates light onto the document on the contact crow and an optical path for guiding light reflected from the document to the photoreceptor 2. a plurality of mirrors 12 and lenses 13;
The color separation filter 14 is rotatably driven within the optical path of reflected light to perform color separation.

The color separation filter 4 has a B (blue) filter, a G (green) filter, an R (red) filter, and a transparent filter assembled in a cross shape, and during color copying, the B, G, and R color filters are sequentially placed in the optical path. A transparent filter is inserted into the optical path to separate the reflected light from the document into colors, while a transparent filter is inserted into the optical path during monochrome copying.

The photoreceptor 2 is driven to rotate in the direction of the arrow, and a silent $ layer image is formed on the surface by light reflected from the original. The entire surface of the photoreceptor 2 is uniformly charged by corona discharge from the charger 7, and an electrostatic latent image is formed thereon.

The developing devices 3c, 3m, and 3y develop this electrostatic latent image with toner to make it visible. The developing units 3c, 3m, and 3y carry out macenter color development, and developing units 3y carry out yellow color development, respectively.In this case, the developing units 3c, 3m, and 3y carry out development using a complementary color relationship with the color filter of the color separation filter 14.

The transfer section 4 is used to transfer the toner image formed on the surface of the photoreceptor 2, and further transfers this transferred image onto recording paper (not shown). This diagonal transfer section 4 includes an endless transfer belt 41 that contacts the surface of the photoreceptor 2 while moving in the direction of the arrow, and a transfer roller 4 that brings the transfer belt 41 into contact with the photoreceptor 2.
Further, a vapor transfer roller 43 is in rolling contact with the lower side of the transfer belt 41 in the figure. After the recording paper is timed by a registration roller 44 provided upstream of the vapor transfer roller 43 (on the left side in the figure), it is conveyed between the vapor transfer roller 43 and the transfer belt 41, and is transferred to the transfer belt 41. A toner image is transferred.

The recording paper onto which the toner image has been transferred is transported to the fixing section 5 by a transport belt 45.

The fixing unit 5 is provided on the downstream side of the conveyor belt 45 in the paper conveyance direction, and includes a fixing roller 51 that fixes the toner image onto the recording paper by heating, and a kite roller 52 that rolls into contact with the fixing roller 51.

Note that a charged body 21, a cleaning device 22, and a static elimination lamp 23 are disposed downstream of the transfer section 4 on the rotational orbit of the photoconductor 2, and these remove toner remaining on the photoconductor 2. Then, static electricity on the surface of the photoreceptor 2 is removed. That is, the charged body 21 uniformly charges the surface of the photoconductor 2, the cleaning device 22 removes toner from the surface of the photoconductor 2, and the charge pump 23 uniformly removes static electricity from the surface of the photoconductor 2, and then the next copy is made. It acts to make it possible.

Further, a cleaning blade 46 for scraping off residual toner on the transfer belt 41 is provided on the moving path of the transfer belt 41.

In addition to the second configuration, an eraser 8 is disposed on the rotation orbit of the photoreceptor 2. The eraser 8 includes an incident part for reflected light from the document that forms an electrostatic latent image on the surface of the photoreceptor 2;
It is provided between the black developing device 3 and. This eraser 8
is an erasing means that eliminates the charge on the photoreceptor 2 and erases the image on the surface of the photoreceptor.No toner image is formed on the photoreceptor part where the charge is removed by the eraser 8, and the recording paper A white area is formed in the area. The eraser 8 eliminates the charge from the corresponding portion of the photoreceptor so as to form a blank area of a predetermined width at the leading edge of the recording paper.

FIG. 2 is a block diagram for controlling the eraser 8. As shown in FIG. The drive of the eraser 8 is controlled by a drive control section 61, and this drive control section 61 is controlled by a CPU 6 as a control means.
2. An operating section 63 is connected to the CPU 62, and signals from the operating section 63 are input. The operation unit 63 is equipped with a selection switch (not shown) for selecting a copy mode of monochrome copy or 'color copy, and the selected copy mode is transmitted to the CPU 62.
Output to.

The CPU 62 controls the entire operation of the copying means (Fig. 1) so as to perform copying in accordance with the selected copy mode, and also forms a white outline of a width corresponding to the selected copy mode on the copy or recording paper. The drive time of the eraser 8 is calculated so that In order to perform the latter control, the CPU 62 stores a table of drive times corresponding to copy modes.

Next, the operation of the above structure will be explained with reference to FIGS. 3 and 4. FIG. 3 is a timing chart when the monochrome copy mode is selected by the operation unit 63;
The figure shows a timing chart when a color copy copy mode is selected. In these figures, the rotation of the photoreceptor 2 is driven by pressing the start switch.
Charging of the photoreceptor 2 and exposure for forming an electrostatic latent image are performed at predetermined timing. In addition, the transfer belt 4
Rotation drive 1 is performed once in the case of Fig. 3 (monochrome copy), and R (red) in the case of Fig. 4 (color copy).
, G (green), and B (blue), so the number of exposures is three times.

The eraser 8 is driven after a predetermined timing using the start of driving of the transfer belt 41 as a trigger. In the case of FIG. 3, the drive of the eraser 8 is such that the colored parts
The timing is controlled so that the width is about the same as that of a cabinet, or in the case of FIG. 4, the width is about 5 to 8 pages.

As a result, a color cutout portion having a width corresponding to each copy mode of monochrome copying and color copying is formed on the recording paper.

Therefore, during copying in each copy mode, the leading edge of the recording paper does not get wrapped around the fixing roller 51, and the recording paper is smoothly fixed and discharged without jamming.

It should be noted that the present invention is not limited to the above embodiments, but
Various modifications are possible; for example, the photoreceptor may be an endless belt and the transfer section may be a roll.6 [Effects of the Invention] As explained above, according to the present invention, monochrome copying,
Since the eraser is controlled to form a white area of a predetermined width at the leading edge of the recording paper according to the copy mode of color copying, the white area can have a width suitable for each copy mode. At the same time, wrapping around the fixing roller can be reliably prevented.

[Brief explanation of drawings]

1 to 4 are diagrams showing one embodiment of a copying apparatus according to the present invention, in which FIG. 1 is a side view showing the configuration of the apparatus, FIG. 2 is a block diagram showing the control system, and FIG. FIG. 4 is a timing chart showing operations during monochrome copying, and FIG. 4 is a timing chart showing operations during color copying. 1...Optical system 2...Photoreceptor 3k, 3m, 3V++++++Developer 4...
...Transfer section 5...Fixing section 8.
... Eraser (erasing means) 62 ... CPU (control means) 63 ...
・Operation unit (operation means)

Claims (1)

[Claims] an operation means for selecting a copy mode of monochrome copying and color copying, and forming an original image on the surface of a photoreceptor;
A copying means that transfers this image onto recording paper and develops it into a visible image corresponding to the copy mode, and a copying means that forms a blank area of a predetermined width at the leading edge of the recording paper, which corresponds to the leading edge of the recording paper. an erasing means for erasing the image on the surface of the photoreceptor to make it a non-image area; and a control means for controlling the driving of the erasing means so that the white area of the recording paper has a width corresponding to the selected copy mode. A copying device comprising: