JPH0566636A - Electrophotographic device - Google Patents

Abstract

PURPOSE:To prevent undesired copying caused by the wrong selection of a transfer form by always making a copy on the transfer forms of the same kind, even if different kinds of the transfer forms are mixed. CONSTITUTION:This electrophotographic device can make a copy on the transfer forms of every kind, which are supplied from a manual paper feeding tray 32, an upper paper feeding cassette 33, and a lower paper feeding cassette 34, and whose brightness is different, and has a form detecting sensor 44 detecting the brightness of the transfer form, and a control means deciding whether a copy is made or not according to the detected transfer brightness. Therefore, the form detecting sensor 44 and the control means discriminate the kind of the transfer form based on the brightness detected from the transfer form, and decide whether a copy is made or not from the result of the discrimination.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic apparatus such as a full-color copying machine capable of sorting colored transfer paper such as recycled paper or colored paper and white transfer paper during copying.

[0002]

2. Description of the Related Art Transfer paper used in electrophotographic devices includes
In addition to normal white transfer paper (hereinafter referred to as colorless transfer paper), there are transfer paper that uses recycled paper and transfer paper that is colored such as yellow or blue (hereinafter referred to as colored transfer paper). Each of these transfer papers is used properly according to the purpose and purpose of copying.

The various transfer papers described above are usually stored in a removable paper cassette unit in a paper supply unit of an electrophotographic apparatus. When copying, the paper cassette is selected so that electrophotography is performed. It is designed to be supplied into the device.
Then, in the conventional electrophotographic apparatus, when the transfer paper is supplied from the selected paper feed cassette, the toner attached to the electrostatic latent image formed on the photoconductor by the exposure of the original image is transferred to the transfer paper, Further, copying is completed by heating and melting the transferred toner and fixing it on the transfer paper.

[0004]

However, in the above-described conventional electrophotographic apparatus, since the transfer paper supplied from the paper feed cassette is copied unconditionally, for example, when the paper feed cassette is selected incorrectly or when the paper feed cassette is selected. When different types of transfer paper are mixed in, the copy is made on a transfer paper of a different type from the target type of transfer paper.

If the original image is made up of characters, diagrams, etc., the copied images copied onto the different types of transfer papers as described above
It can be used because it does not hinder the reading of copied images except for the difference in transfer paper, but it is very difficult to use. Furthermore, when full-color copying is performed in which the color of the original image is faithfully reproduced by a full-color copying machine, which is a type of electrophotographic device, the color of the transfer paper is superimposed on the full-color copied image, so that the color is faithfully reproduced. It becomes impossible and cannot be used at all.

As described above, since the conventional electrophotographic apparatus unconditionally copies the transfer paper supplied from the paper feed cassette, a copy image that is difficult to use or a copy image that cannot be used at all can be obtained due to a mistake in selecting the transfer paper. However, there is a problem that unnecessary copying may be performed as a result. Therefore, in the present invention, it is possible to provide an electrophotographic apparatus capable of preventing unnecessary copying by not performing copying when a transfer sheet of a type different from a target type of transfer sheet is supplied. Has a purpose.

[0007]

In order to solve the above-mentioned problems, the electrophotographic apparatus of the present invention can be copied onto various transfer papers having different lightness such as color transfer paper and colorless transfer paper. It has the characteristics of

That is, the above electrophotographic apparatus is a paper detection sensor which is a lightness detection means for detecting the lightness of the transfer paper, and a control means which is a judgment means for judging whether or not copying is to be performed based on the detected lightness of the transfer paper. And means.

[0009]

According to the above construction, the lightness detecting means and the judging means can judge the kind of the transfer paper based on the lightness detected from the transfer paper.
Whether or not to make a copy is determined from the determination result. Therefore, the electrophotographic apparatus having the lightness detection means and the determination means can always copy onto the same type of transfer paper even when different types of transfer paper are mixed, so that the transfer paper can be selected. It is possible to prevent unnecessary copying due to mistakes.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The following will describe one embodiment of the present invention with reference to FIGS.

The full-color copying machine, which is the electrophotographic apparatus according to the present embodiment, has a color copying mode and a black-and-white copying mode for copying an original image in a single color, and a full-color copying mode for faithfully reproducing and coloring the original image. Is executable.

As shown in FIG. 1, the above-described full-color copying machine has a transparent original placing table 1 on the upper surface thereof, and an original to be copied is placed on the original placing table 1. It has become. An exposure optical system 2 is disposed below the original document table 1, and the exposure optical system 2 irradiates the original document placed on the original document table 1 with light.
2a, a plurality of reflecting mirrors 2b for guiding the reflected light from the document onto the photoconductor 7 as shown by a chain line, an imaging lens 2c arranged on the optical path, and red, green, and blue And a color separation filter 2d having three primary color filters.

Below the exposure optical system 2, a photoconductor 7 is arranged which is irradiated with the above-mentioned reflected light. The photoconductor 7 is formed in a belt shape stretched around a first roller 14 and a second roller 15, and these first and second rollers are provided.
The rollers 14 and 15 are adapted to drive the photoconductor 7 to rotate. Further, between the photoconductor 7 and the exposure optical system 2, a black and white developing tank 3 and color developing tanks 4 to 6 are arranged in a non-contact state with the photoconductor 7, and In the developing tanks 4 to 6, color developers including yellow, magenta, and cyan color toners and carriers are individually stored.

A main charger unit 30 for charging the photoconductor 7 is provided above the photoconductor 7 between the developing tank 6 and the first roller 14, and the first roller 14 is provided.
Below the photoconductor 7 between the second roller 15 and the second roller 15, a photoconductor cleaner unit 31 for removing the toner remaining on the photoconductor 7 is provided.

Further, an intermediate transfer member 10 which is pressed against the photosensitive member 7 is disposed on the outer periphery of the photosensitive member 7 on the side of the second roller 15, and the intermediate transfer member 10 includes first to third rollers. 18
・ It is designed to be rotationally driven by 19 ・ 20.
The intermediate transfer member 10 is provided with the third roller 20 described above.
And a transfer roller 21 disposed so as to face the third roller 20, and between the transfer roller 21 and the intermediate transfer body 10, various kinds of colored transfer paper, colorless transfer paper, etc. are provided. The transfer paper is carried in from the unitized paper supply unit 45 of FIG. A transfer belt 11 that transfers the transfer paper on which the color toner has been transferred from the intermediate transfer member 10 is disposed on the transfer roller 21 and the transfer side of the intermediate transfer member 10. Is provided with a fixing device 12 that heats and melts the color toner to fix it on the transfer paper.

As shown in FIG. 3, the paper feed section 45 includes a manual paper feed tray 32 on which a transfer paper is placed, an upper paper feed cassette 33 and a lower paper feed cassette 34 for containing the transfer paper. , And a conveyance path 35 for guiding the transfer paper in the direction of the transfer roller 21 described above.

In the above-mentioned manual paper feed tray 32, upper paper feed cassette 33, and lower paper feed cassette 34, paper empty detectors 36 are provided on the side of the conveyance path 35, and the paper empty detector 36.
.. is designed to detect the presence of transfer paper.

Further, in the manual paper feed tray 32, the upper paper feed cassette 33, and the lower paper feed cassette 34, the pickup roller 51, the upper paper feed roller 39, and the upper paper feed roller 39 of FIG. Lower paper feed rollers 40 are provided respectively. Then, the calling roller 51, the upper paper feeding roller 39,
A manual feed roller 37, an upper feed roller 41, and a lower feed roller 42 are provided on the sides of the lower feed roller 40 and the lower feed roller 40, respectively, and between the manual feed roller 37 and the upper feed roller 41. A paper path detector 52 that detects whether or not the transfer paper has passed is provided.

The transfer sheet sent to the conveying path 35 is conveyed from the upper conveying roller 41 toward the lower conveying roller 42, and the paper path detector 52 described above is conveyed in the conveying direction of the lower conveying roller 42. Similarly to the paper path detector (PPD) that detects whether or not the transfer paper has passed.
2) 50 is provided and the registration roller 43
The registration roller 43 holds the transferred transfer paper until the formation of the toner image on the intermediate transfer body 10 is completed.

The rollers 51, 37, ...
39, 40, 41, 42, 43, as shown in FIG.
The rollers 51, 37, 39, 40, 41, 42, 43 are rotated and stopped by driving means provided on the sides of the rollers. This drive means includes gears 47 ...
7 ... rotation of each roller 51.37.39.40.41.
The clutch unit 48 includes a clutch pawl and a clutch sleeve that are transmitted to the gears 42 and 43, and a solenoid 49 that drives the clutch pawl.

As shown in FIGS. 1 and 3, a paper detection sensor 44, which is a lightness detection means, is arranged between the registration roller 43 and the lower conveyance roller 42 driven by the above-mentioned driving means. .. The paper detection sensor 44 is composed of, for example, a CCD line sensor or the like, and detects the brightness of the transfer paper and outputs the detected value to a control means which is not shown determination means. The detected value indicating the lightness of the transfer paper shows a large value because the colorless transfer paper has a higher reflectance than the colored transfer paper.

The above control means is a CPU (Central Proc
essing unit), a storage unit including a RAM (Random Access Memory) and a ROM (Read Only Memory), and the ROM has a minimum level detection value when the color transfer paper is measured by the paper detection sensor 44. Is stored as a set value, and the transfer paper discrimination routine of FIG. 5 is also stored. Then, the above-described transfer paper determination routine compares the detection value from the paper detection sensor 44 with the set value, determines whether the transfer paper is a colorless transfer paper or a colored transfer paper, and is the colorless transfer paper. The copying is executed only when it is determined that

The operation of the full-color copying machine which is an electrophotographic apparatus having the above-mentioned structure will be described.

First, when performing full-color copying in the full-color copying mode, as shown in FIG.
The original placed on the original is scanned by being irradiated with light from the light source lamps 2a. Then, the reflected light of the light applied to the original is incident on the image forming lens 2c through the reflecting mirrors 2b ... And the color separation filter 2d, is separated into color components by the color separation filter 2d, and is then reflected. The photoconductor 7 is irradiated through the mirrors 2b.

The above-mentioned scanning is repeated three times for each color component, and the light for each color component transmitted through each color filter of the color separation filter 2d is exposed uniformly by the main charger unit 30. The body 7 is sequentially irradiated, and the photoreceptor 7 is imagewise exposed. As a result, an electrostatic latent image for each color component corresponding to the image of the original is sequentially formed on the photoconductor 7.

Each of the above electrostatic latent images has a color separation filter 2d.
Developing tanks 4 to 6 having developers of respective colors of yellow, magenta, and cyan which are complementary colors of the respective color filters in
At the portion opposite to, the toner image is developed by each developer supplied from the developing magnet roller and visualized to form a toner image formed by each color toner.The toner image for each color component is an intermediate transfer. It is transferred to the same position on the body 10. As a result, one toner image in which the toner images of the respective color components are overlaid is formed on the intermediate transfer member 10 by the end of the three scans.

On the other hand, the control means executes the transfer sheet determination routine of FIG. 5 by executing the full-color copying mode, and whether or not the toner image formed on the intermediate transfer member 10 is transferred to the transfer sheet. Will be determined.

That is, as shown in FIG. 6, when the transfer paper is supplied from the manual paper feed tray 32, the upper paper feed cassette 33, or the lower paper feed cassette 34 to the paper feed path 35, the upper paper feed rollers 41 and the lower paper feed rollers 35 are provided. The conveyance roller 42 conveys it toward the registration roller 43. Then, the leading end of the conveyed transfer paper is detected by the paper path detector 50, and is output to the control means as a leading end detection signal.

At this time, the control means, as shown in FIG.
It is determined whether or not the leading edge of the transfer sheet is detected, and this determination is repeated until the above leading edge detection signal is input (S1). Then, when the leading edge detection signal is input, the control unit recognizes that the transfer sheet has been conveyed to the registration roller 43, and causes the sheet detection sensor 44 to start detecting the brightness of the transfer sheet (S2). ).

The above-mentioned paper detection sensor 44 outputs a detection value indicating the brightness of the transfer paper to the control means, and the control means outputs a detection value higher than the set value indicating the brightness of the color transfer paper. It is determined whether or not the value is small (S3). If the detected value is smaller than the set value, it is determined that the transfer paper is a color transfer paper, and
The toner image formed on the intermediate transfer body 10 is discharged without being transferred to the transfer sheet, or a warning display indicating that the transfer sheet is not a colorless transfer sheet is displayed and the transfer sheet determination routine is ended. (S4).

On the other hand, when the detected value is larger than the set value, it is determined that the transfer sheet is a colorless transfer sheet, the result is NO and the transfer sheet determination routine is ended, and the transfer sheet is formed on the intermediate transfer member 10 in FIG. After transferring the toner image onto the transfer paper, the fixing device 1
The toner image is fixed on the transfer paper by the method 2.

As described above, in the full-color copying machine of this embodiment, the transfer roller 21 is transferred before the toner image is transferred onto the transfer paper.
Whether the transfer paper conveyed to is a colorless transfer paper or a color transfer paper is confirmed, and the toner image is transferred only when it is confirmed that the transfer paper is a colorless transfer paper. As a result, the full-color copying machine can always transfer the toner image onto the colorless transfer paper even when the upper and lower paper feed cassettes 33 and 34 are erroneously selected or different kinds of transfer paper are mixed. Therefore, it is possible to prevent unnecessary copying due to a wrong selection of transfer paper.

In this embodiment, whether or not the toner image can be transferred according to the result of the discrimination between the colorless transfer paper and the colored transfer paper is described using the full-color copying machine, but the present invention is not limited to this. Whether or not transfer is possible based on the above determination result may be adopted in an electrophotographic apparatus other than a full-color copying machine.

Further, in this embodiment, the color transfer paper and the colorless transfer paper are discriminated from each other, but the present invention is not limited to this, and the brightness obtained from various transfer papers is subdivided. Therefore, various types of transfer paper may be discriminated. As a result, the electrophotographic apparatus can always make a copy using the transfer paper of the desired type.

[0035]

INDUSTRIAL APPLICABILITY As described above, the electrophotographic apparatus of the present invention is capable of copying on various kinds of transfer papers having different brightness, and the brightness detecting means for detecting the brightness of the transfer paper and the detected transfer. It is configured to have a determination unit that determines whether or not to copy based on the brightness of the paper.

Thus, the lightness detecting means and the judging means can judge the type of the transfer paper based on the lightness detected from the transfer paper, and can judge whether or not to make a copy based on the result of the judgment. Even when the transfer papers are mixed, it is possible to always copy to the same kind of transfer paper, and it is possible to prevent unnecessary copying due to a mistake in the selection of the transfer papers.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an electrophotographic apparatus of the present invention.

FIG. 2 is a perspective view of a unitized sheet feeding unit.

FIG. 3 is a schematic configuration diagram of a paper feeding unit.

FIG. 4 is a schematic configuration diagram of a driving unit of a sheet feeding unit.

FIG. 5 is a flowchart of a transfer sheet determination routine.

FIG. 6 is an explanatory diagram showing a flow of conveyance of a transfer sheet in a sheet feeding unit.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Document placing table 2 Exposure optical system 3 to 6 Developing tank 7 Photoconductor 10 Intermediate transfer body 11 Conveyor belt 12 Fixing device 14 First roller 15 Second roller 18 First roller 19 Second roller 20 Third roller 21 Transfer roller 31 Photoconductor cleaner unit 32 Manual paper feed tray 33 Upper paper feed cassette 34 Lower paper feed cassette 35 Conveyance path 37 Manual paper feed roller 36 Paper empty detector 39 Upper paper feed roller 40 Lower paper feed roller 41 Upper paper feed roller 42 Lower paper feed roller 43 Registration roller 44 Paper detection sensor 45 Paper feed section 46 Chain 47 Gear 48 Clutch section 49 Solenoid 50 Paper path detector 51 Call roller 52 Paper path detector

Claims (1)

[Claims] 1. An electrophotographic apparatus capable of copying on various types of transfer paper having different brightness, and a brightness detecting means for detecting the brightness of the transfer paper, and whether or not copying is to be performed is determined based on the detected brightness of the transfer paper. An electrophotographic apparatus having a determining unit.