JPH0925039A - Image forming device - Google Patents

Abstract

(57) An object of the present invention is to provide an image forming apparatus having a structure capable of realizing space saving, high productivity, and capable of double-sided image formation. A reading unit for reading an original on a platen, an image forming unit for recording image data of an original image read by the reading unit on a transfer sheet as a visible image, and a transfer sheet subjected to image formation are provided. In an image forming apparatus having a stacking sheet discharge section, the sheet discharge section is arranged below the reading section, and two side walls facing each other that define the sheet discharge section discharge sheets. The mouths are arranged to face each other.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a copying machine, a printer,
The present invention relates to an electrophotographic image forming apparatus such as a facsimile, and more particularly to a double-sided image forming apparatus that saves space and has high productivity.

[0002]

2. Description of the Related Art In an image forming apparatus using an electrophotographic process such as a copying machine, a printer and a facsimile machine, a document reading section exposes and scans a document surface set on a document table such as a contact glass. After reading the original image and irradiating the obtained optical image data directly on the photoconductor, or after the reflected light of the original image is once formed on the CCD etc. and subjected to photoelectric conversion etc. An electrostatic latent image is formed on the photoconductor by irradiating the photoconductor with image data composed of laser light. This electrostatic latent image is visualized by the toner from the developing device, and this visible image is transferred and fixed on the transfer paper. Recent image forming apparatuses are equipped with an automatic document feeder, a double-sided copying function, etc., and are functionally improved. However, due to the increase in functions, it is inevitable that the apparatus becomes large, and there is a demand for space saving. The result is contrary.

Japanese Utility Model Publication No. 6-13153 discloses an image forming apparatus that forms an image while an original is fed in page order by an automatic document feeder, and the opening and closing means opens and closes the conveying path to open the conveying path. Since the sheet is fed by the feeding means when the feeding operation is performed, the feeding sheet is prevented from colliding with the opening / closing means and a jam is prevented. In comparison, a configuration that can reduce the manufacturing cost and noise can be disclosed. However, in this conventional technique, the automatic document feeder used to feed documents in page order is an automatic document feeder compatible with single-sided originals and cannot support double-sided originals and is inferior in function. .

Further, Japanese Laid-Open Patent Publication No. 63-13153 discloses an automatic document feeder which is equipped with an upper document separating / feeding unit and a lower document separating / feeding unit and can feed a document from either the upper side or the lower side. A configuration having a forming function is disclosed, and it is possible to selectively use paper feed of an automatic document feeder as upper or lower depending on an image forming mode. However, the automatic document feeder of this conventional example cannot avoid inevitably increasing in size and cost, and does not meet the demands of the age of space saving and cost reduction. Also, since the order of feeding originals differs depending on the mode, control becomes complicated,
This point also causes a cost increase, and the structure is such that double-sided originals cannot be supported.

[0005]

SUMMARY OF THE INVENTION The present invention has been made in view of the above, and provides an image forming apparatus which has a structure capable of realizing space saving, has high productivity, and is capable of double-sided image formation. The purpose is to do.

[0006]

In order to achieve the above object,
The present invention provides a reading unit for reading a document on a platen, an image forming unit for recording image data of a document image read by the reading unit on a transfer sheet as a visible image, and a transfer sheet subjected to image formation. In an image forming apparatus having a stacking sheet discharge section, the sheet discharge section is arranged below the reading section, and two side walls facing each other that define the sheet discharge section discharge sheets. The mouths are arranged opposite to each other.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will now be described in detail with reference to the embodiments shown in the accompanying drawings. FIG. 1 is a diagram illustrating the overall configuration of an example of an image forming apparatus to which the present invention is applied. In this image forming apparatus, an automatic document feeder (ADF) 1 is arranged on a main body 2 of a digital copying machine, and the ADF 1 is a slit glass located directly above a reading unit 5 located on the main body 2 of the copying machine. 26, the contact glass 27 is pivotally supported so as to open and close. When a document is fed by the ADF 1 to make a copy, the reading unit 5 of the copying machine main body 2
The exposure unit (such as the lamp 28) is fixed at the position shown in the figure. At this position, the light from the lamp 28 is directed through the slit glass 26 toward the original surface passing through the slit glass at a predetermined speed. Read by irradiating. One of the characteristic configurations of the present invention is the reading unit 5 described above.
The paper discharge unit 3 for the transfer paper is arranged immediately below the position, and this arrangement structure realizes space saving of the entire apparatus. The paper discharge unit 3 is a void provided in the main body 2 of the copying machine, and the void is formed by side walls 1A and 1B located on the left and right sides and a back wall 1C located on the back side. The front side is opened so that the transfer paper can be easily taken out.

Next, the overall structure of the image forming apparatus of the present invention will be described. First, the ADF 1 includes a table 16 on which the original 6 is set, a calling roller 7 for taking out the original, a set sensor 8 for detecting whether the original is set on the table 16, and a separation roller pair 9 for separating the called original. A transport roller 10 for transporting the original document to the reading position, a paper discharge roller 11 for discharging the original document that has been read by passing through the slit glass 26, and a registration sensor 12.
Further, it has a paper ejection sensor 13, a switching claw 14 for switching the conveyance direction of the document, a reversing path 15, and the like.

Next, the copying machine main body 2 has a slit glass 2
6, the contact glass 27, the lamp 28 constituting the reading unit 5, the mirrors, and the paper discharge unit 3 located immediately below the reading unit
An image forming unit 30 (photoconductor drum 31, transfer device 32, fixing device 33, etc.) located below the paper discharge unit 3, and a double-sided unit 40 (double-sided tray 41, double-sided path 42, paper discharge roller 43, separation unit). (Roller pair 44, double-sided path 45, etc.), a paper feed tray 50 for accommodating the transfer paper P, a paper feed roller 51, a conveyance roller 55 arranged in the transfer paper conveyance path, and a transfer paper transferred to a photoreceptor. Registration roller 56 to be supplied to the device
And the direction of conveyance of the transfer paper which has been fixed is set to the paper discharge unit 3 side (first
Paper discharge path 70), a switching claw 60 for switching to the duplex unit 40 side path 42, and a sensor 61 that detects the transfer paper that has been fixed and is conveyed to the paper discharge unit 3 side. Further, although the first paper discharge path 70 ends at the first paper discharge port 3A, a second paper discharge path 71 is formed along the upper side of the paper discharge unit 3 from the end portion, and the second paper discharge path 71 is formed. The paper discharge path 71 of is terminated at the second paper discharge path 3B.

The side wall 1A of the paper discharge section 3 is formed with a first paper discharge port 3A, and the side wall 1B is formed with a second paper discharge port 3B. The first paper ejection roller 7 is provided in the first paper ejection port 3A.
5, the second paper discharge rollers 3 are respectively arranged in the second paper discharge port 3B. Further, a discharge switching claw 77 is arranged at a connecting portion between the end of the first discharge path 70 and the start of the second discharge path 71.

Next, a copying operation using a single-sided original by the image forming apparatus having the above configuration will be described with reference to the transport path diagrams of FIGS. 1 and 2. First, the single-sided original 6 is placed in the ADF 1
When paper is fed to form an image, the table 16
Place the original face up on top. The presence or absence of setting is detected by the set sensor 8 and a detection signal is output to the control unit. When a start button of an operation unit (not shown) provided on the copying machine main body 2 is turned on, the ADF 1 and the copying machine main body 2
Then, the original 6 is taken out by the calling roller 7, separated by the separating roller pair 9, and conveyed on the slit glass 26 by the conveying roller 10. The original 6 that has passed the slit glass 26 and has been read is conveyed by the roller 1.
The sheet is discharged in the direction of the arrow by 0 and the discharge roller 11 and is stacked on the stack unit 17. At this time, the switching claw 14 is at the position indicated by the solid line, and the discharged documents are stacked in page order with the document surface facing downward.

The procedure for conveying the transfer paper P in the main body 1 of the copying machine when a single-sided original is read is as follows. That is, the transfer paper P on the paper feed tray 50 is taken out by the paper feed roller 51, conveyed by the conveyance roller 55 and the registration roller 56 between the photoconductor drum 31 of the image forming section and the transfer section 32, and exposed. The toner image on the body is transferred, and the transferred transfer paper is fixed by the fixing device 33. The transfer sheet that has been fixed is sent out to the first sheet discharge path 70 by the transport roller 55 and the switching claw 60 located at the solid line position.

When the paper discharge switching claw 77 is in the solid line position, the transfer paper that has been sent to the first paper discharge path 70 is sent to the first paper discharge port 3A, and when it is in the dotted line position, it is the second line.
It is sent to the second sheet discharge port 3B via the conveyance path 71 of. When the one-sided original is read, the switching claw 77 is in the solid line position, and the transfer paper is ejected from the paper ejection port 3A to the paper ejection unit 3. As a result, the transfer sheets are stacked in page order with the image forming surface facing downward.

Next, the operation of forming an image while reading the original by feeding the double-sided original 6'by the ADF 1 will be described with reference to FIGS. First, the main body of the copying machine is set to the double-sided copy mode by operating the switch of the operation unit. When the start switch is turned on in this state, the first page of the originals set on the table 16 with the original surface of the first page facing upward is taken out by the calling roller 7 and the separation roller pair 9 and slits. When it passes through the glass 26, it is read by the reading unit 5, and after reading, it is discharged from the paper discharge port with the first page facing downward, but it is not stacked in the stack unit 17,
The rear end portion is nipped by the paper discharge roller 11 and is suspended (FIG. 3 (a)). That is, the switching claw 14 is in the position indicated by the solid line during the reading of a double-sided document, and when the sensor 13 located downstream of the switching claw 14 detects the passage of the rear end portion 6'of the transfer sheet, the operation of the sheet ejection roller 11 is performed. Since the control unit controls the operation so as to stop the operation, the transfer sheet 6 ′ is stopped in the state where the rear end portion of the transfer sheet 6 ′ is nipped by the sheet discharge roller 11.

Immediately after the discharge roller 11 is stopped, the control unit
The switching claw 14 is moved to the position indicated by the chain line, and the paper discharge roller 11 is started to rotate in the reverse direction so that the original 6'is rotated in the reverse path 15
To (Fig. 3 (b)). The original 6 ′ sent to the reversing path 15 receives the second page by passing through the slit glass 26 with the second page facing downward.
It is guided by the switching claw 14 that has returned to the solid line position and is conveyed to the sheet discharge port. At this time, if the originals are stacked on the stack section as they are, the second page faces downward and the page order is disturbed. Therefore, the paper discharge roller 11 is temporarily stopped and the rear end of the document is nipped by the paper discharge roller 11. After switching the switching claws 14 again, the document is passed through the slit glass (reading position) through the reversing path 15 and is ejected and stacked on the stacking unit 17 with the first page facing downward. Of course, reading is not performed at the time of this re-inversion. The paper feeding, reading, and reversing operations are performed for each original, and the reading is finally completed as shown in FIG. As a result, the documents on the stack section are stacked in page order.

In the document reversing operation shown in FIG. 3B, high-speed conveyance is performed until the reversed document reaches the sensor 12, so that the total time required for paper feeding can be shortened. Further, for the same reason, it is preferable that the reversing operation for aligning the pages after the back side reading shown in FIG.

Next, FIGS. 4 (a) and 4 (b) show a procedure of transporting the transfer paper on the copying machine main body side when a double-sided document is transported by the procedure of FIGS. 3 (a) and 3 (b). FIG. 4A is a diagram showing a state in which the image obtained by reading the image of the first page of the double-sided original is formed on the transfer paper and then the transfer paper is set in the double-sided unit 40. At this time, the switching claw 60
Is located at the position indicated by the dotted line, and guides the one-sided copy transfer sheet to the duplex unit 40 side (double-sided path 42). FIG.
(b) shows the order of conveyance of the transfer paper that has been copied on both sides. At this time, the switching claw 60 is at the solid line position in FIG.
Moreover, since the switching claw 77 is located at the position indicated by the dotted line in FIG. 1, the transfer sheet that has undergone double-sided copying in the image forming unit 30 is guided from the first sheet discharge path 70 to the second sheet discharge path 71. Second
The transfer paper guided to the paper discharge path 71 of
The sheet is reversed at the end of the sheet and is discharged into the sheet discharge section 3 from the second sheet discharge port 3B. At this time, the transfer sheets are stacked with the odd-numbered pages facing downward. When the sensor 61 detects the rear end of the transfer sheet immediately after passing through the switching claw 60 and a detection signal is input to the control section, the control section controls the transfer system to transfer the transfer sheet at high speed.

Since the present invention is configured as described above, the original and the transfer paper can be discharged and stacked in a state where the page order is aligned by the conveyance in the same direction without the reverse conveyance, which is quiet and has high production efficiency. Image formation can be realized. Furthermore,
Since the paper discharge unit 3 is located below the reading unit 5, space saving can be realized. In addition, the left and right wall surfaces of the paper output unit 3 that face each other are provided with paper output ports, respectively, and the transfer paper after copying is fed back by switchback or the like in accordance with either one-sided or two-sided copy mode. Without doing
It is possible to carry and discharge the sheet, and as a result, it is possible to shorten the sheet interval of the transfer sheet and realize a highly productive copy. Further, since the conveying operation is uniform and smooth, it is possible to provide a quiet image forming apparatus without collision noise or the like. Further, since the order of image processing is the page order, control can be simplified, the configuration can be simplified, and the cost can be reduced.

FIG. 5 is a flow chart showing the transfer paper conveyance path. When performing double-sided copying, the switching claw 6 is used.
While holding 0 at the open position indicated by the chain line, the single-sided recording transfer sheet discharged from the image forming unit 30 was once conveyed to the double-sided unit 40, and was re-fed to the image forming unit 30 to receive a copy on the back side. Later, since the switching claw 60 is switched to the solid line position this time, the switching claw 60 enters the paper discharge path 70 and is guided by the switching claw 77 in the open state shown by the chain line to the second position.
Is sent to the paper discharge path 71, and is discharged from the paper discharge port 3B.
Is discharged into (steps 1, 2, 3, 7, 8, 4,
5, 9, 10). When performing one-sided copying, after the image formation, the switching pawl 60 in the closed state shown by the solid line enters the first paper discharge path 70 and is guided by the switching pawl 77 in the closed state shown by the solid line. The sheet is discharged from the first sheet discharge port 3A into the sheet discharge section 3 (steps 1 to 6).

[0020]

As described above, according to the present invention, the reading unit 5
Since the paper discharge unit 3 is arranged at a position immediately below, it is possible to realize space saving. In addition, the left and right wall surfaces of the paper output unit 3 that face each other are provided with paper output ports, respectively, and the transfer paper after copying is fed back by switchback or the like in accordance with either one-sided or two-sided copy mode. Without doing
It becomes possible to selectively convey and discharge paper to each paper exit.
As a result, it is possible to reduce the distance between the transfer sheets and realize a highly productive copy. Further, since the conveying operation is uniform and smooth, it is possible to provide a quiet image forming apparatus without collision noise or the like. Further, since the order of image processing is the page order, control can be simplified, the configuration can be simplified, and the cost can be reduced.

[Brief description of drawings]

FIG. 1 is an overall configuration explanatory diagram of an example of an image forming apparatus to which the present invention is applied.

FIG. 2 is an explanatory diagram of a document transport path for a single-sided document.

3 (a), (b) and (c) are explanatory views of a document transport path for a double-sided document.

FIG. 4A and FIG. 4B are explanatory views of a transporting path of a transfer sheet when double-sided copying is performed.

FIG. 5 is a flowchart showing the operation of one embodiment of the present invention.

[Explanation of symbols]

1 automatic document feeder (ADF), 1A, 1B side wall,
2 Digital copying machine main body, 3 paper ejection section, 3A, 3B paper ejection opening, 5 reading section, 6 originals, 7 call rollers, 8
Set sensor, 9 separation rollers, 10 transfer rollers, 1
1 Paper Ejection Roll, 12 Registration Sensor, 13 Paper Ejection Sensor, 14 Switching Claw, 15 Inversion Path, 16 Table, 17 Stack Section, 26 Slit Glass, 27
Contact glass, 28 lamps, 30 image forming unit, 31 photoconductor drum, 32 transfer device, 33 fixing device, 40 double-sided unit, 41 double-sided tray, 42
Double-sided path, 43 paper ejection roller, 44 separation roller pair, 45
Double-sided path, 50 paper feed tray, 51 paper feed roller, 55
Transport rollers, 56 registration rollers, 60 switching claws, 6
1 sensor, 70 1st paper discharge path, 71 2nd paper discharge path, 75 1st paper discharge roller, 76 2nd paper discharge roller, 7
7 Paper output switching claws,

Claims (1)

[Claims] 1. A reading unit for reading a document on a platen, an image forming unit for recording image data of a document image read by the reading unit on a transfer sheet as a visible image, and a transfer sheet subjected to image formation. In the image forming apparatus having a sheet discharging section for stacking the sheets, the sheet discharging section is arranged below the reading section, and two side walls that face each other and define the sheet discharging section are discharged respectively. An image forming apparatus characterized in that paper openings are arranged opposite to each other.