JP2001147566A - Electrophotographic image forming device provided with both-surface printing mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an electrophotographic image forming device provided with both-surface printing mechanism in which large impact is not applied to the opening and closing part of a bothsurface printing mechanism even when the procedure of paper jam processing is mistaken. SOLUTION: Since a frictional material becoming a load at a rotating time is imparted to the rotary part of the paper jam processing cover of the both- surface printing mechanism, the movement of the opening action of a cover becomes dull when the cover is opened because the frictional material becomes resistance. Thus, even in the case that the cover of a printing device main body is opened because an operation procedure is mistaken at the paper jam processing time, the paper jam processing cover of the both-surface printing mechanism fitted to it is not opened in such a way that it receives impact.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic image forming apparatus having a duplex printing mechanism capable of performing duplex printing.

[0002]

2. Description of the Related Art In general, an electrophotographic image forming apparatus receives print data and develops it into image data.
An image is formed by irradiating the photosensitive member with a light beam such as a laser beam.
On the other hand, a medium such as paper is transported to the photoconductor by a transport unit such as a roller, and an image formed on the photoconductor is transferred. Then, the image is fixed on the paper by the fixing device,
Print (print). In such an electrophotographic image forming apparatus, printing is often performed only on one side,
Printing on both sides has been required.

For this purpose, a sheet on which an image is formed on one side by a fixing device is sent to a transfer unit again, and printed on the other side of the sheet. At that time, if the paper is simply sent, the paper will be printed on the same surface as the already transferred surface when the paper is sent to the transfer means. Is provided.

In such an electrophotographic image forming apparatus, a double-sided printing mechanism is disclosed in JP-A-6-312867 or JP-A-7-128921.
As in the case of the above-mentioned item, a form attached to the electrophotographic image forming apparatus is usually used.

Further, during use of the electrophotographic image forming apparatus, a so-called paper jam that rarely stops the conveyance in the conveyance path due to poor conveyance of the paper may occur.
In such a case, a paper jam clearing cover provided in each transport path is opened to take out the paper inside. When performing paper jam processing inside the printing device main body, open the double-sided printing mechanism and then open the cover of the printing device main body to perform paper jam processing.However, if the cover of the printing device main body is suddenly opened, printing will be performed. The double-sided printing mechanism attached to the outside of the device hinders the cover of the main unit from opening, or even if it is open, there is no support, so the paper jam handling cover of the double-sided printing mechanism will open with an impact, It is necessary to prevent the paper jam processing cover of the double-sided printing mechanism from being opened with an impact even when opened from the paper jam processing cover of the main body.

[0006]

Since the paper jam processing of the electrophotographic image forming apparatus occurs inside the apparatus, the first consideration is to open the paper jam processing cover of the printing apparatus main body. Therefore, it is easy to forget to open the cover of the double-sided printing mechanism attached to the printing apparatus body first. Therefore, when the paper jam processing cover of the printing apparatus main body is opened, the cover of the double-sided printing mechanism opens vigorously, and an impact is applied to the rotating portion. SUMMARY OF THE INVENTION It is an object of the present invention to provide an electrophotographic image forming apparatus with a double-sided printing mechanism in which a large impact is not applied to the opening / closing portion of the double-sided printing mechanism even when the procedure of paper jam processing is erroneous.

[0007]

In order to achieve the above object, according to the present invention, a frictional material serving as a load at the time of rotation is applied to a rotating portion of a paper jam processing cover of a double-sided printing mechanism. This serves as a resistance to slow down the opening operation.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

The printing apparatus main body 25 includes developing devices 1 to 4,
The optical unit 5, the charger 8, the photosensitive belt 22, the transfer drum 21, the registration roller 12, the transfer roller 13, the static eliminator 15, the fixing device 19, the paper discharge roller 18, and the paper feed cassette a6 are main components. The control block diagram is shown in FIG. The control blocks are roughly two blocks of a printing apparatus main body control section 100 and a non-transfer paper apparatus control section 101. The printing apparatus main body control unit 100 exchanges data with the host, an I / F unit, an exposure, development, fixing unit, a motor as a power source, a solenoid driving unit, an operation unit, a display unit, a paper feeding unit, It comprises a sequence control unit for controlling some detectors and the like and a paper reversal control unit. Further, the control unit 101 includes a motor as a power source, a driving unit of a solenoid, some detectors, and the like, and is operated by a signal from the sheet reversing control unit.

The operation of the printing device 25 and the non-transfer paper device 26 will be described.

The charger 8 uniformly charges the photosensitive belt 22 in response to a print start signal from a host (not shown). The optical unit 5 draws a latent image on the photosensitive belt 22 based on print data sent from the host. The drawn latent image is developed by any one of the developing units 1 to 4, and the colored particles in the developing unit are applied on the photosensitive belt 22. The photosensitive belt 22 is rotated by a driving source not shown here, and the photosensitive belt 2 is placed on the transfer drum 21.
2. Transfer the colored particles on 2. Excess colored particles remaining on the transfer drum 21 are removed by the drum cleaner 20.

Excess colored particles remaining on the photosensitive belt 22 are removed by a belt cleaner 23 and charged by the charger 8 again. In the case of color printing, this process is repeated a plurality of times while switching the developing device.

FIG. 6 shows a conventional example of an electrophotographic image forming apparatus in which printing is performed on one side only. On the transfer drum 21, a visible image formed by colored particles of a single color or a plurality of colors is formed. The paper a27 is pulled out from the paper cassette a6 by the paper feed roller a10 at the time when the desired transfer is completed or beforehand, and waits at the registration roller 12. Also, after a predetermined time, the paper feed roller a
10 stops. At a timing when the position of the visible image formed on the transfer drum 21 coincides with the transfer position on the sheet, the sheet waiting at the registration roller 12 starts conveying again, and the transfer roller 13 At this point, the visible image is transferred to the paper side. The paper is separated from the transfer drum 21 by the neutralizer 15, and the colored particles are fixed to the paper by the fixing device 19. In the case of printing on only one side, the switch 17 does not operate, and the paper aa40 is discharged to the discharge tray 28 side.

FIG. 5 shows a conventional electrophotographic image forming apparatus, in which a non-transfer paper device 26 is mounted to perform double-sided printing. When printing on paper b35, a paper feeding device d45 is used. From the paper cassette b7 stored in the
35 is pulled out by the paper feed roller b24, and the paper feed device d
45, a sheet supply conveyance path a provided in the printing apparatus main body 25 by a conveyance roller b11 via a conveyance path d44.
Supplied from 29, and stands by at the registration roller 12, and thereafter, the same operation as that described in FIG. 6 is performed.

In the case of double-sided printing, the switch 17 is lowered and taken into the non-transfer paper device 26 side, and the paper aaa 39
Is transported by the transport roller a16 and the paper transport guide a14 to the reversing temporary storage section 9 located on the rear side of the printing apparatus main body 25. At this time, the curl applied to the paper a27 on which the first surface is printed is corrected by taking a curved path provided in the reversing temporary storage section 9 in a direction opposite to that of the fixing device 19.

Regarding the printing position deviation, the sheet feeding from the non-transferring paper device 26 and the sheet position variation from the sheet cassettes a6 and b7 can be adjusted so that the printing position can be finely changed. The printing position can be kept constant.

The state of conveyance of the sheet from the sheet cassette b7 stored in the sheet feeding device d45 to the reversing temporary storage section 9 is indicated by an arrow, but the sheet aaa39 is on the second side.
In order to perform transfer to the (back side), the sheet is pulled out of the reversing temporary storage section 9 by a driving source (not shown) and passes through a transport path formed by the paper transport guide a14 and the transport roller a16 of the anti-transfer paper device 26. Then, the paper is supplied from the transport roller b11 to the paper supply transport path a29 provided in the printing apparatus main body 25 via the transport path d44 of the paper feeding device d45, and is transported again into the printing apparatus main body 25.
After that, it stands by at the registration roller 12 and is held at the position of the registration roller 12.

At this time, the second surface (back surface) is
The print data on the second side (back side) is
The sheet is sent from the host either during conveyance of the paper on which printing on the first surface (front surface) is completed or after being stored in the reversing temporary storage unit 9, and a visible image is created on the transfer drum 21 in the above-described process. Is done. The position of the visible image formed on the transfer drum 21 is
At a timing coincident with the transfer position on the sheet, the sheet waiting at the registration roller 12 starts conveying again, and the visible image is transferred to the back surface of the sheet at the transfer roller 13. The paper is transferred to the transfer drum 21 by the neutralizer 15.
The colored particles are further peeled off and fixed by the fixing device 19 on the back surface of the paper. The switch 17 is operated so as to discharge the paper to the paper discharge tray 28 side, and the paper aa for which printing on both sides is completed.
40 is discharged onto the paper discharge tray 28.

In such a configuration, one embodiment of the present invention firstly attaches an arrow a41, an arrow b42, an arrow b42 to the printing apparatus main body 25 as shown in FIGS. From the direction of arrow c43, the anti-transfer paper device 26, the paper feed device b3
7. Attach the paper feeder c38. The printing device body 25
Contains a paper cassette a6 storing paper a27. Further, the paper cassette b7 storing the paper b35 is stored in the paper feeding device b37. The paper feeder c38 houses a paper cassette c34 storing paper c36, and includes a transport roller c31, a transport path c32, and a paper feed roller c33.

Paper c3 stored in paper cassette c34
In the case of printing 6, the paper c36 is pulled out by the paper feed roller c33, and is conveyed to the conveyance path b30 provided in the paper feeding device b37 by the conveyance roller c31 via the conveyance path c32. Then, the transport roller b11
Then, the sheet is supplied from the sheet supply / transport path a29 provided in the printing apparatus main body 25, and waits at the registration roller 12.

In this case, the transport route c32 and the transport route b3
In the sheet feeding device c38 and the sheet feeding device b37, the sheet No. 0 is configured at the same position, so that the sheet can be conveyed by a simple path, and the sheet is supplied to the sheet supply conveyance path a29 without any problem. Is what you can do.

Thereafter, when printing on one side, FIG.
In the case of performing the same operation as the content described in the above and performing double-sided printing, the same operation as the content described in FIG.
The paper aaa39 is to be transferred to the second surface (back surface).
The sheet is drawn out of the reversing temporary storage unit 9, passes through a conveyance path constituted by the sheet conveyance guide a 14 and the conveyance roller a 16 of the non-transfer paper device 26, and passes through the conveyance path b
30, the printing apparatus main body 2 from the conveying roller b11.
5 is supplied to the paper supply / conveyance path a29 provided in the printer 5 and conveyed again into the printing apparatus main body 25. Thereafter, it stands by at the registration roller 12 and is held at the position of the registration roller 12. The paper jam generated in the printing apparatus main body 25 mainly occurs at the transfer unit, the fixing unit, and the paper discharge unit when the paper is fed from the cassette. Of those, the paper jam generated at the fixing unit or the paper discharge unit is the paper discharge tray. 28 will be opened and removed. At this time, the paper jam processing cover 51 is first opened, and then the paper discharge tray 28 is opened to perform the paper jam processing. At this time, if the discharge tray 28 is opened first,
The paper jam processing cover 51 is pushed by the paper discharge tray 28 and is opened. Since the rotation centers of the paper ejection tray 28 and the paper jam processing cover 51 are not the same, the paper jam processing cover 51 moves away from the printing apparatus main body 25 side. At this time, the sliding piece 53 attached between the hinge and the fixed portion of the paper jam processing cover 51 acts so as to load the opening movement of the paper jam processing cover 51, and the paper jam processing cover 51 does not suddenly open. .

FIG. 9 shows the case where the non-transfer paper device 26 is not mounted on the printing device main body 25, and the paper feed device b3
7. A single-sided printing can be performed in a large amount by mounting the paper feeding device c38, and can be effectively utilized as a system according to the purpose of printing.

The transport roller b11 and the transport path b3
0, the paper feed roller b24 is connected to the transport rollers c31,
By having the same configuration as the transport path c32 and the paper feed roller c33, the paper feeder b37 and the paper feeder c38 can be shared.

Therefore, the height of the entire apparatus can be adjusted in accordance with the use situation, and the apparatus can be made compact according to the amount of paper used. It can be standardized and can be configured at low cost as a printing device system.

[0026]

According to the present invention, in an electrophotographic image forming apparatus provided with a double-sided printing mechanism, even if the operation procedure is erroneously opened and the cover of the printing apparatus main body is opened during paper jam processing, the double-sided printing attached to the printing apparatus body is performed. The paper jam handling cover of the mechanism can be prevented from opening so as to receive impact

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a printing apparatus according to an embodiment of the present invention when a paper jam processing cover of a double-sided printing mechanism is opened.

FIG. 2 is a cross-sectional view of a printing apparatus in a case where a sheet is conveyed from a lowermost sheet feeding apparatus and duplex printing is performed according to an embodiment of the present invention.

FIG. 3 is a cross-sectional view of a printing apparatus according to an embodiment of the present invention when a sheet is conveyed from a first-stage sheet feeding apparatus at a lower portion of the printing apparatus to perform double-side printing.

FIG. 4 is a cross-sectional view of a printing apparatus in which a sheet feeding apparatus according to an embodiment of the present invention is mounted, a sheet stored in a printing apparatus main body is transported, and duplex printing is performed.

FIG. 5 is a cross-sectional view of a printing apparatus in a case where a paper feeding apparatus according to a conventional example is mounted and duplex printing is performed.

FIG. 6 is a cross-sectional view of a printing apparatus for performing single-sided printing in a conventional example.

FIG. 7 is a cross-sectional view of the printing apparatus showing the mounting of the non-transfer paper device and the paper feeding device according to the embodiment of the present invention.

FIG. 8 is a control block diagram of a printing apparatus showing one embodiment of the present invention.

FIG. 9 is a cross-sectional view of a printing apparatus according to an embodiment of the present invention, in which only paper feeding apparatuses are mounted in multiple stages.

[Explanation of symbols]

REFERENCE SIGNS LIST 1 developing device 1, 2 developing device 2, 3 developing device 3, 4 developing device 4, 5 developing device 4, 5 optical unit 6, paper feed cassette a, 7… paper cassette b, 8… charging device 9 Temporary storage unit, 10
... Supply rollers a, 11 ... Transport rollers b, 12 ... Registration rollers, 13 ... Transfer rollers, 14 ... Paper transport guide a
15: static eliminator, 16: transport roller a, 17: switch, 1
Reference Signs List 8: paper discharge roller, 19: fixing device, 20: drum cleaner, 21: transfer drum, 22: photosensitive belt, 23: belt cleaner, 24: paper feed roller b, 25: printing device main body, 26: anti-transfer paper device , 27: paper a, 28: paper discharge tray, 29: paper supply transport path a, 30 ... transport path b,
31 transport rollers c and 32 transport paths c and 33 paper feed rollers c and 34 paper cassettes c and 35 paper b and 36
Paper c, 37: paper feeder b, 38: paper feeder c, 39 ...
Paper aaa, 40 ... Paper aa, 41 ... Arrow a, 42 ... Arrow b, 43 ... Arrow c, 44 ... Transport path d, 45 ... Paper feeder d, 46 ... Fixing screw, 47 ... Hook, 48 ... Fixing plate,
49: shaft, 50: guide, 51: paper jam processing cover,
52: Stop stay, 53: Sliding piece, 100: Printing device main body control unit, 101: Non-transfer paper device control unit.

 ────────────────────────────────────────────────── ─── Continuing on the front page (72) Inventor Shin Nakamura 1-1-1, Higashitaga-cho, Hitachi City, Ibaraki Prefecture F-term (reference) 2H071 AA02 AA19 AA42 DA23 EA04 3F100 AA02 BA14 CA12 CA14 DA01 EA06

Claims (2)

[Claims] A sheet cassette for storing sheets, a transfer member on which an image is formed, a conveying means for conveying the sheet to the transfer member, a fixing device for fixing a transferred image of the sheet, In an electrophotographic image forming apparatus having a double-sided printing mechanism having means for feeding the paper to the transfer body so that an image is transferred to a non-fixed side, a paper jam processing cover that opens and closes the double-sided printing mechanism and double-sided printing An electrophotographic image forming apparatus with a double-sided printing mechanism, wherein a friction member is provided between the mechanism and a fixing portion attached to a printing apparatus main body. 2. A non-woven fabric according to claim 1, wherein the non-woven fabric is sandwiched between a hinge portion of the paper jam processing cover and a hinge fixing portion of the paper jam processing cover of a fixing portion of the double-sided printing mechanism attached to the printing apparatus body. An electrophotographic image forming apparatus with a double-sided printing mechanism.