JP2001341946A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image forming device having large space efficiency and cost merits and easy in jam processing. SOLUTION: When discharging a sheet to a sorter 1E, the image formed sheet is carried to a sheet placing part 606 of the sorter 1E via a carrying passage 605 arranged in the sorter 1E from a paper discharge passage 601a. When forming images on both surfaces of the sheet, the sheet forming the image on one surface is sent out to a recarrying passage 701 after being carried once to the carrying passage 605 from the paper discharge passage 601a, and the sheet forming the image on one surface is reversed, and is carried to an image forming part 1C.

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, and more particularly, to an apparatus having a function of forming an image on both sides of a sheet.

[0002]

2. Description of the Related Art A digital copying machine, which is an example of an image forming apparatus using an electrophotographic system, has a double-sided image forming function capable of forming an image on both sides of a sheet. In addition to the functions described above, what is called a digital multifunction peripheral having both a function as a printer for a personal computer and a function as a facsimile has become widespread.

Here, in such a digital copying machine, an original image is read by an image sensor such as a CCD provided in an image reading section and converted from optical information into an electric signal. It is sent to the control unit of the device main body, and after that, A / D conversion and
Processing such as shading correction and density processing is performed and output to the image forming unit.

In the image forming section, a latent image is formed on the photosensitive drum by exposing the photosensitive drum in accordance with the original image information, and the latent image is developed by developing the latent image. A toner image is formed on a drum. As an exposure method in this image forming unit, an optical scanning optical system that deflects and reflects a light beam on each deflecting surface of an optical deflector composed of a rotating polygon mirror and optically scans a surface to be scanned composed of a photoreceptor is used. Is widely used.

By the way, in such a copying machine,
Since only the electric signal needs to be passed from the image reading unit to the image forming unit, the image reading unit and the image forming unit can be arranged with a high degree of freedom. For this reason, for example, as in the image forming apparatus disclosed in JP-A-10-181978 shown in FIG. 6, the sheet conveying path 51 that passes through the image forming unit 50 is disposed substantially vertically, and the sheet is discharged below the image reading unit 52. Part 5
By providing 3, the sheet conveying path 51 can be shortened and a compact apparatus can be provided.

[0006]

In such a conventional copying machine, as a method for realizing a double-sided image forming function, a sheet on which an image is formed on one side is inverted and re-fed to an image forming section. There is known an apparatus using a sheet circulation path. As shown in the figure, in a copying machine having a configuration in which the sheet conveying path 51 is arranged substantially vertically, a sheet circulation path 54 for double-sided image formation is provided on Circuit 5
A path 55 for reversing the sheet is provided adjacent to the sheet No. 4 so that the sheet is reversed and re-fed.

However, when such a dedicated path 55 for reversing the sheet is provided, the size of the apparatus is increased, the space efficiency is deteriorated, the jam clearance is deteriorated due to the complicated path, and the manufacturing cost associated with the increase in size is reduced. There was a problem of an increase in distribution costs.

Accordingly, the present invention has been made in view of such circumstances, and an object of the present invention is to provide an image forming apparatus which has great space efficiency and cost merit, and can easily perform jam processing.

[0009]

According to the present invention, when an image is formed on a sheet and an image is formed on both sides, the sheet on which the image is formed on one side is turned over and then conveyed to the image forming section again. In an image forming apparatus configured to form an image on the back surface of the sheet, a sorter that discharges the sheet on which the image is formed, a paper discharge path that conveys the sheet on which the image is formed to the sorter, A transport path provided in the sorter and transporting a sheet transported from the paper discharge path to a sheet placement unit provided in the sorter, and transporting a sheet having an image formed on one side to the image forming unit; Re-conveying path, when forming images on both sides,
The sheet on which the image is formed on one side is turned over so that the sheet is once conveyed from the paper discharge path to a conveying path provided in the sorter so as to be conveyed to the image forming section, and then sent out to the re-conveying path. It is characterized by having made it.

[0010] The present invention further comprises another sheet discharging section from which the sheet on which the image is formed is discharged, and the sheet on which the image is formed is selectively passed through the sheet discharging path to the other sheet discharging section. Or transported to the transport path of the sorter.

Further, the present invention is characterized in that the another sheet discharging section is provided at an upper portion of the apparatus main body.

Further, the present invention is characterized in that a part of the sheet is discharged and placed on the sheet placing portion and then turned over.

Further, the present invention is characterized in that the re-conveying path is provided in a direction opposite to the sheet conveying direction of the conveying path, and the re-conveying path and the conveying path are provided in one housing. Is what you do.

Further, the present invention is characterized in that the transport path and the re-transport path are provided vertically.

Further, the present invention is characterized in that a manual sheet feeding section for performing manual sheet feeding is provided, and the manual sheet feeding section is disposed immediately below the re-conveying passage.

When the sheet is discharged to the sorter as in the present invention, the sheet on which the image is formed is conveyed from the sheet discharge path to the sheet mounting portion of the sorter via the conveying path provided in the sorter. When images are formed on both sides of the sheet, the sheet on which the image is formed on one side is once conveyed from the sheet discharge path to the conveying path of the sorter, and then sent out to the re-conveying path, so that the image is formed on one side. The formed sheet is inverted and conveyed to the image forming unit.

[0017]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a view for explaining the overall configuration of a multi-function digital copying machine as an example of an image forming apparatus according to an embodiment of the present invention, and FIG. 2 is a perspective view of the same.

1 and 2, reference numeral 1 denotes a multifunction digital copying machine, and 1A denotes a multifunction digital copying machine main body (hereinafter referred to as an apparatus main body). A scanner unit 1B serving as an image reading unit for reading, an image forming unit 1C for forming an image on a sheet is disposed at a central portion, and a sheet feeding unit 1D for feeding a sheet to the image forming unit 1C is further disposed at a lower portion. I have. Further, on one side surface of the apparatus main body 1A, there are provided a sorter 1E which is a paper discharge unit for sorting and discharging a sheet on which an image is formed by the image forming unit 1C into a plurality of bins, and a manual paper feed unit 1G. I have.

Here, the scanner section 1B includes a scanning system light source 2
07 with first mirror 201, platen glass 20
2. a document pressure plate 203 that can be opened and closed with respect to the apparatus main body 1A;
It has a second mirror 204, a lens 205, a light receiving element (photoelectric conversion element) 206, an image processing unit (not shown), and the like.

The image forming section 1C has an electrophotographic photosensitive drum 112, a charger 113, a developing device 114, a transfer charger 115 and the like. Then, when a laser beam corresponding to image information emitted from the laser scanner 111 is scanned on the surface of the photosensitive drum 112 uniformly charged by the charger 113, a latent image is formed on the surface of the photosensitive drum,
Further, by developing this latent image by the developing device 114, a toner image is formed on the surface of the photosensitive drum.

Thereafter, when the sheet is conveyed to a nip portion between the photosensitive drum 112 and the transfer charger 115 as described later, the toner image formed on the photosensitive drum 112 is transferred to the sheet. Has become.

The sheet feeding section 1D includes a sheet cassette 2, a pickup roller 3 for picking up sheets stored in the sheet cassette 2, a separation pad 4, and the like.
After the sheet is picked up by the pickup roller 3, the separation pad 4 and the pickup roller 3 cooperate to separate and feed the sheet one by one.

Further, the sheet thus separated one by one is thereafter guided to a registration roller 106 by a pair of transport rollers 104 and 105, and then the registration roller 1
At 06, the toner image is fed to the image forming section 1C (the nip between the photosensitive drum 112 and the transfer charger 115) in synchronization with the image forming operation, and the toner image is transferred. The sheet on which the toner image is formed is conveyed to the fixing device 118, and is heated and pressurized when passing through the fixing device 118, so that the toner image is fixed on the sheet surface.

The sorter 1E includes a sorter tray 606 for sorting sheets, and a sorter transport path 605, which is a transport path for transporting the sheets discharged from the image forming section 1C after the images are formed to the sorter tray 606. I have. In the figure, reference numeral 604 denotes a sorter transport path 605.
Pair of reversible rollers provided at the entrance side of
Reference numeral 04a denotes a pair of paper discharge rollers which are provided on the discharge port side of the sorter transport path 605 and which can be rotated forward and backward.

The manual paper feed section 1G includes a manual paper feed table 801 on which sheets to be fed are stacked, and a feeding roller 80.
2 and a separation pad 803, and the sheets set on the manual paper feed tray 801 are separated and fed one by one by the cooperation of the feeding roller 802 and the separation pad 803, and then the registration rollers 106 are provided. Is supplied to the image forming section 1C in synchronization with the image forming operation.

In the figure, reference numeral 602 denotes a paper discharge passage 60 for switching the paper discharge direction of the sheet after fixing.
1a is a flapper provided in the discharge branch part 601;
When the sorter 1E is not used, the sheet after fixing is selectively guided in the in-machine discharge direction by the flapper 602, and is formed by the discharge roller pair 119 on the bottom surface of the discharge space M provided in the upper portion of the apparatus main body 1A. The paper is discharged and stacked face-down with the recording surface facing down on a discharge tray 300 as another discharge unit.

A recording medium detecting means 301 for detecting the presence or absence of a sheet on the discharge tray 300 is provided on the discharge tray 300.
When the sheet is discharged, the recording medium detecting means 301 moves by the weight of the sheet as shown by a dotted line, and detects this by an actuator and a sensor (not shown), thereby detecting the presence of the sheet. It is configured to detect.

Reference numeral 501 denotes a heat-generating unit such as a power supply unit; and 350, an air duct. The air duct 350 is composed of the heat-generating unit 501 and the image forming section 1C.
By providing the air duct 350 at such a position, the number of means for cooling the image forming unit 1C can be reduced.

On the other hand, when the sorter 1E is used, the flapper 602 is switched to a state in which the fixed sheet S is guided in the sorter discharge direction as shown in FIG. Reversing roller pair 60
4. The sheet is conveyed in the order of the sorter conveying path 605, and is discharged and stacked on a sorter tray 606a, which is a predetermined (lowest) sheet mounting portion, with the recording surface facing up.

The multifunction digital copying machine 1 functions as a copying machine when a processing signal of an image processing unit is input to the laser scanner 111, and functions as a printer when an output signal of a personal computer is input. If a transmission signal from a facsimile device of another device is input or a processing signal of an image processing unit is transmitted to a facsimile device of another device, the device functions as a facsimile device.

Then, the sheets are placed in any of the sorter trays 6.
For example, whether or not to discharge to 06 is determined by selectively using the multi-function digital copying machine 1 as a copying machine or as a printer, or by branching by designating by the user. You. In FIG. 2, reference numeral 50 denotes an operation unit, and 51 denotes a display unit. Further, display control means and operation control means (not shown) are also arranged in the apparatus main body.

Next, an image forming operation of the multifunctional digital copying machine 1 having the above-described configuration will be described.

First, a book document such as a book, thick paper, curled paper, or the like (not shown) or a sheet-shaped document is placed on the platen glass 202 with the document surface facing down. In this state, when a reading start key (not shown) provided on the operation unit 50 is pressed, the first mirror 201 having the scanning system light source 207
02, the image information on the document surface is read by scanning below.

The image information of the document scanned by the first mirror 201 is stored in the second mirror 204 and the lens 20.
After being projected onto the light receiving element 206 by 5 to read image information, it is processed by an image processing unit, converted into an electric signal, and transmitted to the laser scanner 111.

Further, in the image forming section 1C, the charger 11
3 forms a latent image by scanning the surface of the photosensitive drum 112 uniformly charged by 3 with a laser beam corresponding to image information emitted from the laser scanner 111, and thereafter, this latent image is developed by the developing device 114. By developing, a toner image is formed on the surface of the photosensitive drum 112.

On the other hand, the sheets stored in the sheet cassette 2 in parallel with the toner image forming operation are picked up by the pickup roller 3 and then separated one by one by the cooperation of the pickup roller 3 and the separation pad 4. After that, the sheet is guided to the registration roller 106 by the conveyance rollers 104 and 105.

Thereafter, the sheet is fed by a registration roller 106 to the nip between the photosensitive drum 112 and the transfer charger 115 of the image forming section 1C in synchronization with the image forming operation. When passing through
The toner image on the photosensitive drum is transferred to a sheet. Then, the sheet on which the toner image has been formed in this manner is conveyed to a fixing device 118, where the sheet is heated and pressed to fix the toner image on the sheet surface.

Next, when the sorter 1E is not used, the sheet on which fixing has been completed is selectively guided in the in-machine discharge direction by the flapper 602 of the discharge branching section 601.
19, the paper is discharged to the paper discharge tray 300 in the paper discharge space M,
Be loaded. On the other hand, when the sorter 1E is used, the sheet after fixing is guided in the sorter discharge direction by the flapper 602, conveyed in the order of the circulation branching section 603, the pair of reversing rollers 604, and the sorter conveying path 605, and discharged to the predetermined sorter tray 606. , Be loaded.

Incidentally, the multi-function digital copying machine 1 according to the present embodiment is configured so that images can be formed on both sides of a sheet, and as shown in FIG. In order to form an image on the back side of a sheet having a toner image formed on one side, a sheet circulating section 1F having a re-conveying path for conveying the sheet to the image forming section 1C again is provided on one side of the apparatus main body 1A. Is provided.

Here, the sheet circulation path 701 is arranged in a direction opposite to the sheet transport direction of the sorter transport path 605, that is, linearly below the sorter transport path 605, and as shown in FIG.
As shown in FIG. 7, the sheet joins the sheet conveying path 600 immediately before the registration roller 106 of the image forming section 1C.

In this embodiment, the sorter 1
E and the sheet circulating unit 1F are formed as an integral housing, and accordingly, the sorter transport path 605 and the sheet circulating path 701 are also provided in one housing. By providing the sorter transport path 605 and the sheet circulation path 701 in one housing in this way, a sheet transfer portion from the sorter transport path 605 to the sheet circulation path 701 can be easily configured. In addition, the manufacturing cost can be kept low.

When an image is formed on both sides of the sheet, the sheet S on which an image is formed on one side in the image forming section 1C is temporarily rotated by the flapper 602 as shown in FIG. After the sheet has been drawn (conveyed) to the sheet circulation path 701, the sheet is reverted just before the rear end of the sheet meets the reversing roller 604, and the sheet S is fed back to the sheet circulation path 701 as shown in FIG. Is transported.

Here, by being switched back from the sorter transport path 605, the sheet S is inverted, and thereafter, the inverted sheet S is returned to the sheet circulation path 70.
1 and immediately before the registration roller 106 of the image forming section 1C, the sheet merges into the sheet conveying path 600, and is re-fed to the image forming section 1C from this junction to form an image on the back surface.

As described above, during double-sided image formation, the sorter transport path 60 for discharging sheets to the sorter tray 606 is used.
By using the sheet 5 as a sheet reversing path, there is no need to provide a dedicated reversing path 55 arranged in the sheet circulation path 54 as shown in FIG. It is possible to provide a multifunctional digital copying machine 1 having functions and a low cost in total.

Also, with this configuration, the sheet recirculation path 701 can be opened with a simple configuration because the reversal path does not interfere, and the sheet recirculation path 70
Even if the sheet is jammed in step 1, the jam processing becomes easy. Furthermore, since the space necessary for the sorter tray 606 is originally used for jam processing, the effective installation area is efficient.

Further, since there is no inversion path, the width of the apparatus main body 1A can be reduced, and the installation area can be reduced.
Further, since the sheet is not exposed to the apparatus main body 1A for reversing, the sheet is not damaged during reversing or the operator does not feel uncomfortable with the exposed sheet, and the reversing sheet is mistaken. Therefore, there is no possibility that the operator pulls or touches the sheet.

Further, even when the manual sheet feeding section 1G is provided below the sheet circulation section 1F as in the present embodiment, the area of the sheet inversion path is secured because the sorter transport path 605 is used as a path for sheet inversion. Manual paper feed unit 1
G can be arranged at an appropriate position below the sheet circulating section 1F, and a device with good sheet setting properties and good usability can be provided.

Further, since the sorter 1E, the sheet circulating section 1F, and the manual feed section 1G can all be arranged on one side of the apparatus main body 1A, the opposite side of the apparatus main body 1A needs to be opened for various trays and jam clearance. Is eliminated, so-called “wall pita installation” can be performed.

In the above description, the sorter 1E and the sheet circulating section 1F are formed as an integral housing. However, the present invention is not limited to this.
F and F may be separated. And like this sorter 1
E and the sheet circulating unit 1F are separated from each other,
And the sheet circulating unit 1F can be formed as compact units, respectively, so that manufacturing and distribution costs can be reduced.

In the above description, a case has been described in which the sheet is reversed inside the sorter transport path 605 when forming a double-sided image. However, the present invention is not limited to this, and the space of the sorter tray 606 is not limited to this. , The sheet may be inverted.

That is, after a part of the sheet received in the sorter transport path 605 is discharged and stacked on the sorter tray, the sheet discharge roller pair 604a provided on the discharge port side of the sorter transport path 605 is rotated in the reverse direction. May be reversed and fed into the sheet circulation path 701.

Here, the sorter tray 606 has a discharge space M
In contrast to this, since the sheet is provided at a position away from the operator, even if the sheet being inverted is exposed on the sorter tray, the operator is not uncomfortable. In addition, in the case of such a configuration, the sorter transport path 605 does not need a length for sheet inversion, so that a short and compact apparatus can be provided.

In this embodiment, the sorter 1E is disposed above the sheet circulating section 1F. However, the sorter 1E may be disposed below the sheet circulating section 1F. In this case, a dedicated inversion path is not required. In addition to this, there is an effect that the number of structures around the image reading unit is reduced and does not hinder the operation.

Further, in the present embodiment, the sorter tray 606 is oriented to the left as shown in FIG.
It may be located above B. In this case, there is an effect that the installation area can be further reduced.

Further, in the present embodiment, the image forming section 1C using the electrophotographic method is used, but the same effect can be obtained in an image forming section using another method such as thermal transfer or ink jet.

[0057]

As described above, according to the present invention, when an image is formed on both sides of a sheet, the sheet on which the image is formed on one side is once conveyed to a conveying path provided in a sorter, and then reconveyed. By feeding the sheet to the passage, the sheet can be inverted without providing a dedicated path for sheet inversion. Accordingly, it is possible to provide an image forming apparatus which realizes a double-sided image forming function which has large space efficiency and cost merit and is easy to perform jam processing.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating an overall configuration of a multi-function digital copying machine as an example of an image forming apparatus according to an embodiment of the present invention.

FIG. 2 is a perspective view of the multifunction digital copying machine.

FIG. 3 is a diagram showing a state in which a sheet is discharged to a sorter provided in the multifunction digital copying machine.

FIG. 4 is a diagram illustrating a state in which a sheet is reversed during double-sided image formation of the multi-function digital copying machine.

FIG. 5 is another view showing a state in which a sheet is turned over when forming a double-sided image in the multi-function digital copying machine.

FIG. 6 is a diagram illustrating a configuration of a conventional image forming apparatus.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Multifunction digital copying machine 1A Main body 1B Scanner part 1C Image forming part 1E Sorter 1G Manual feed part 1F Sheet circulation part 601a Discharge path 605 Sorter conveyance path 606a Sorter tray 701 Sheet circulation path S Sheet

Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme coat II (Reference) B65H 39/11 B65H 39/11 H 3F100 G03G 15/00 106 G03G 15/00 106 F term (Reference) 2H028 BA06 BA09 BA16 BA16 3F050 BC01 BC04 BE06 LA01 LB03 3F053 BA14 EA01 EB01 EB04 EC02 ED15 LA01 LB03 3F054 AA01 AC01 BF08 BF22 BF24 DA01 DA02 3F063 AA01 AB01 AB06 BA02 BA10 3F100 AA02 BA23 CA12 CA13 CA15 DA11 EA02 EA03 EA03

Claims (7)

[Claims] When forming an image on a sheet and forming an image on both sides, the sheet on which an image is formed on one side is turned over, and then conveyed again to an image forming section to print the image on the back side of the sheet. In the image forming apparatus configured to form, a sorter that discharges the sheet on which the image is formed, a paper discharge path that conveys the sheet on which the image is formed to the sorter, A transport path for transporting the sheet transported from the paper path to a sheet placement unit provided in the sorter, and a re-transport path for transporting the sheet having an image formed on one side thereof to the image forming unit. When forming an image on both sides, the sheet on which the image is formed on one side is turned over, and the sheet is once conveyed from the paper discharge path to a conveyance path provided in the sorter so as to be conveyed to the image forming section. I An image forming apparatus configured to send the sheet to the re-conveying path after the image forming apparatus. 2. The image forming apparatus according to claim 1, further comprising another sheet discharging unit from which the sheet on which the image is formed is discharged, wherein the sheet on which the image is formed is selectively transferred to the other sheet discharging unit via the sheet discharging path. The image forming apparatus according to claim 1, wherein the image is conveyed to a conveyance path of the sorter. 3. The image forming apparatus according to claim 2, wherein the other sheet discharging unit is provided at an upper part of the apparatus main body. 4. The image forming apparatus according to claim 1, wherein a part of said sheet is discharged and placed on said sheet placement section, and then the sheet is turned over. 5. The re-conveying path is provided in a direction opposite to a sheet conveying direction of the conveying path, and the re-conveying path and the conveying path are provided in one housing. An image forming apparatus according to any one of claims 1 to 3. 6. The image forming apparatus according to claim 1, wherein the transport path and the re-transport path are provided in a vertical direction. 7. A manual paper feed unit for performing manual paper feed,
7. The image forming apparatus according to claim 1, wherein the manual sheet feeding unit is disposed immediately below the re-conveying path.