JPH05229183A - Image forming device - Google Patents

Abstract

PURPOSE:To obtain a small sized low cost image forming device with a read sensor without staining the surface of a copy by a method wherein the read surface of the read sensor is so arranged as to face the surface opposed to the printing surface by an image forming part of paper. CONSTITUTION:When image information of a copy is read, the copy of a cassette paper feeder 1 passes through a paper feed path 3, and is read with a read sensor 16 while it is being transferred through a transfer path 4 by taking timing with a pair of timing rollers 17. Then, the copy which has passed through the sensor 16 and finished to be read, passes through a photosensitive material 6 and a fixing device 6 in the same way as of the recording paper in printing and is discharged to a delivery part 13. Herein, the read surface of the paper when the copy is read becomes the rear surface opposite to the printing surface of the paper when an image is formed on the recording paper. Therefore, though the copy is intended to be contained as the paper in the paper feed part 1 to perform read operation, printing operation happens to be erroneously performed. Though toner sticks to the paper with the photosensitive material 6, since the toner adhering surface is the rear surface not the copy surface, the copy surface is avoided from being stained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image forming apparatus having a reading sensor such as a printer, a copying machine and a facsimile.

[0002]

2. Description of the Related Art A conventional image forming apparatus is disclosed in, for example, Japanese Patent Laid-Open No.
No. 166962, a facsimile machine (see FIG. 3) or a copying machine (see FIG. 4) known from Japanese Examined Patent Publication No. 2-17466 (see FIG. 4) is used to feed sheets of paper to the conveyance path 101 and the image forming unit 102. The transport path 103 for transporting and forming an image is configured independently. Since such a conventional apparatus requires two transport paths, there is a problem in that the apparatus becomes large and the price becomes high accordingly.

Although not yet known, the applicant of the present invention configures a small apparatus, and therefore, a sheet is used to form an image on a sheet in a conveyance path for reading image information of a document by a reading sensor and an image forming unit. An image forming apparatus has been proposed in which the conveying path for conveying is formed as one conveying path in common.

In the previously proposed image forming apparatus, as shown in FIG. 2A, the reading sensor 52 and the image forming section 53 are arranged on the same side with respect to the sheet conveying path 51, and the sheet is formed by the image reading surface 52a of the reading sensor 52. The reading surface of the sheet is the same as the image printing surface of the sheet by the image forming unit 53, and if a document is intended to be read as the sheet but printing is performed due to an operation error or the like, the document surface is printed. , There is a risk of spoiling the manuscript.
Further, when a document is passed through for reading, there is a possibility that the document surface may become dirty due to the adhesion of toner when the document passes through the printing section.

[0005]

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above problems and to provide an image forming apparatus with a reading sensor which is small in size and low in price without contaminating the surface of the original when the original is passed. It is an issue.

[0006]

SUMMARY OF THE INVENTION The present invention addresses the above-mentioned problems by a reading sensor, an image forming section for forming an image based on an image information signal from the reading sensor, and a sheet feeding section to an image forming section. An image forming apparatus in which the reading sensor is disposed between the sheet feeding unit and the image forming unit of the conveying path, the reading sensor has a reading surface of the sheet. The problem is solved by the image forming apparatus that is arranged so as to face the surface opposite to the printing surface of the image forming unit.

[0007]

According to the present invention, as shown in FIG.
Since the reading sensor 52 and the image forming unit 53 are arranged on the opposite sides of the sheet 1, the sheet reading sensor 52
The surface read by the image reading surface 52a is the surface opposite to the surface printed by the image forming unit 53. Therefore, even if a document is mistakenly fed and printed, it is not printed on the document surface, and the image of the document is not damaged. Further, even if toner adheres when passing through the image forming section 53, it is possible to prevent the image surface of the original document from being soiled because it is the back surface rather than the original surface.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The details of the present invention will be described based on the embodiments shown in the drawings.

In an electrophotographic printer as an example of an image forming apparatus, as shown in FIG. 1, a recording sheet 2 is fed from a sheet feeding section 1, for example, a cassette sheet feeding apparatus 1 through a feeding path 3 and a conveying path 4. And sent to the registration roller pair 5. The recording paper 2 is sent by a pair of registration rollers 5 to a latent image carrier composed of a photosensitive member 6 of a drum which constitutes an image forming section.

The photosensitive member 6 is rotationally driven counterclockwise in the figure, the surface of the photosensitive member 6 is charged by the charging charger 7, and a laser beam from the laser optical system 8 is irradiated to form an electrostatic latent image on the surface. ..

When the electrostatic latent image passes through the developing device 9, it is toner-developed by the developing roller 10 to be a visible image, and the visible image is transferred to the recording paper 2 by the transfer charger 11 and transferred. The visible image of is fixed by the fixing device 12. The fixed recording paper is ejected and stored in the paper ejection unit 13.

On the other hand, the residual toner on the photoconductor 6 after the transfer is removed by the cleaning device 14, and the removed toner is collected in the toner collecting tank 15.

A reading sensor 16 is arranged between the sheet feeding section 1 of the conveying path 4 and the photoconductor 6 constituting the image forming section, and a timing roller pair 17 is provided in front of the reading sensor 16 on the conveying path 4. After the reading sensor 16, a pair of feed rollers 18 is provided if necessary.

The reading sensor 16 and the photoconductor 6 forming the image forming portion are arranged at positions opposite to each other with respect to the conveying path 4. Therefore, the image reading surface by the reading sensor 16 of the paper conveyed on the conveying path 4 and the image printing surface by the photoconductor 6 are opposite to each other.

When the image information of the original is read, the original stored in the cassette sheet feeding device 1 passes through the feeding path 3 and is read while being conveyed by the timing roller pair 17 in the conveying path 4 at a timing. It is read by the sensor 16. The original that has passed through the reading sensor 16 and has been read is the same as the recording paper when printing, and the photoconductor 6 and the fixing device 1
The sheet is discharged to the sheet discharge section 13 through the sheet 2.

When an image is formed by the image information read by the reading sensor 16 or by the image information sent from another host device, the paper accommodated in the cassette paper feeder 1 is switched from the original to the recording paper.

The recording paper fed from the cassette paper feeding device 1 is fed by the registration roller pair 5 (however, the reading sensor 16 does not operate) in the same manner as in the case of the above-mentioned original, and the image is formed by the transfer by the photoconductor 6. The sheet is formed, fixed by the fixing device 12, and discharged to the discharge unit 13.

According to this apparatus, the reading surface of the paper when reading the original is the back surface of the printing surface of the paper when the image is formed on the recording paper. Therefore, even if a stack of documents is stored in the paper feed unit 1 as a sheet and is read in, and the toner is attached to the sheet by the photoconductor 6 by mistake, the toner-adhering surface is not the original surface but the back surface. Therefore, it is possible to avoid soiling the document surface.

A manual paper feeding device 19 is provided in the conveying path 4 so that a small amount of recording paper or manuscript can be manually fed in front of the timing roller pair 17 addressed to one sheet.

The image forming unit includes a photosensitive member 6, a developing roller 10 of the developing device 9, a toner stirring member 20 of the developing device 9, a stirring member 21, and the like, which are driven to rotate.

The apparatus shown in FIG. 1 has a common paper feed unit and a single paper feed path for both originals and recording papers, which enables downsizing and cost reduction of the image forming apparatus. Further, since the image reading surface by the reading sensor and the printing surface by the image forming unit are opposite to each other, it is possible to prevent the document surface from being soiled.

In the example shown in the drawing, the electrophotographic system is described, but the image forming apparatus of any system such as the ink jet system, the thermal transfer system and the wire dot system can be applied.

[0023]

According to the present invention, since the original conveyance path and the recording paper conveyance path are common and the printing surface of the image forming portion of the paper and the reading surface of the reading sensor are opposite surfaces, the original surface is soiled. A compact and low-priced image forming apparatus with a reading sensor was obtained.

[Brief description of drawings]

FIG. 1 is an overall schematic diagram of an image forming apparatus according to the present invention.

FIG. 2 is a layout view of a reading sensor and an image forming unit, where A is a previously proposed apparatus and B is a schematic layout view of the apparatus according to the present invention.

FIG. 3 is a schematic diagram of a conventional image forming apparatus.

FIG. 4 is a schematic view of another conventional image forming apparatus.

[Explanation of symbols]

 1 Paper Feeding Section 4 Conveying Path 6 Photoreceptor (Image Forming Section) 16 Reading Sensor

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Office reference number FI Technical display location H04N 1/00 108 Q 7046-5C H 7046-5C

Claims (1)

[Claims] 1. A reading sensor comprising: a reading sensor; an image forming unit that forms an image based on an image information signal from the reading sensor; and a conveyance path that conveys a sheet from a paper feeding unit to the image forming unit. In the image forming apparatus in which is arranged between the paper feeding unit and the image forming unit of the conveyance path, the reading sensor faces a surface of the paper opposite to the printing surface of the image forming unit. An image forming apparatus characterized in that the image forming apparatus is arranged.