JPH11344847A - Image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To perform card board operation without through a fixing part, without providing a dedicated paper feeding tray for the card board. SOLUTION: The both-side device 6 is provided with a stacking part 6a, a side fence 9, a secondary switching pawl 10, an access roller 12, the both side roller 13 and the both side re-feeding paper route 14. Then, the card board discharging route 15 that directly connects the both side device 6, and the paper discharge part is arranged. When the card board P1 is set on the stuck part 6a, the card board P1 is called by the access roller 12, and oriented toward the card board discharge route 15 by the second switching pawl 10. The card board P1 reachs the paper discharge part through the card board discharge route 15, and is fed in the post processing device, or discharge as it is.

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 such as a copying machine or a printer, and more particularly to a blank sheet or another image-formed transfer sheet as a cover or a separator between image-formed transfer sheets. And an image forming apparatus having a so-called interleaving mode (interleaving function).

[0002]

2. Description of the Related Art As described above, in an image forming apparatus, there is a method of inserting an interleaving paper between transfer papers which normally make a copy. Conventionally, interleaving paper is set on a tray other than the one used for copy operation, paper feeding operation is performed from the interleaving tray at the timing when interleaving is required, and it passes through the image forming unit in the same way as normal copying Then, the interleaf work (interleaf processing) was performed. Here, a transfer sheet on which an image has already been formed may be used as the slip sheet. In recent years, with the spread of color image forming apparatuses, there is a need to use transfer paper on which a color image has been formed as a slip sheet of a monochrome machine. However, in general, since the melting point of the color toner is lower than the melting point of the monochrome toner, the color transfer Image defects on transfer paper due to melting of color toner when paper passes through the fixing section,
Problems such as contamination of the fixing roller and jamming around the fixing roller occur. Therefore, as shown in FIG. 4, a paper feed tray 3 dedicated to slip sheets is newly disposed downstream of the image forming unit 1 and downstream of the fixing unit 2.
A mechanism for performing interleaving without passing through the fixing unit 2 has been conventionally employed.

[0003]

However, when a paper feed tray dedicated to slip sheets as shown in FIG. 4 is used, there is a problem that the entire image forming apparatus becomes large and the cost increases.
In addition, a side fence that regulates the horizontal direction is required to match the transport position with the copy paper, even though the tray is dedicated to the slip sheet.

A first object of the present invention is to provide an interleaving operation without passing through a fixing unit without providing a paper feeding tray dedicated to interleaving paper, which results in an image defect on transfer paper and a fixing roller. An object of the present invention is to provide an image forming apparatus capable of preventing problems such as dirt and jamming around a fixing roller and reducing the size and cost of the apparatus. A second object of the present invention is to provide an image forming apparatus which can move a side fence of a stack portion of a double-sided apparatus to prevent a lateral registration deviation or skew of slip sheets.

[0005]

The first problem is that a transfer paper is fed and conveyed from a paper feed tray, an image is formed in an image forming section, and then the paper is conveyed to a post-processing section. After forming, once stacked on the double-sided device, and re-fed, after re-feeding from the double-sided device in the image forming apparatus having a path for forming an image on the back surface in the image forming unit again,
By switching the transport path, there is a mechanism that is transported to the post-processing section without being transported to the image forming section, and a mechanism that is capable of setting sheets in the stack section of the duplex apparatus. And an interleaf function for inserting an interleaf between the transfer paper on which an image is formed, and when the interleaf function is selected, an image is formed from a paper feed tray and conveyed to the post-processing unit. The interleaving paper is fed from the double-sided apparatus to the transferred paper at a necessary timing, and the interleaving process is performed by the first unit. Further, the second problem is that, in the first means, a side fence is provided in a stack portion of the double-sided device, and the side fence is set by a driving unit such as a motor by setting a paper size of the slip sheet. The problem is solved by the second means that moves according to the size of the slip sheet. Further, the second problem is that, in the first means, a side fence is provided in a stack portion of the double-sided device, and after selecting a slip sheet function, the stacking portion is adjusted according to the size of the transfer sheet in the selected sheet feeding tray. The third fence moves the side fence according to the size of the transfer paper by a driving means such as a motor. Further, the second problem is solved by a fourth means in the first means, wherein a side fence is provided in a stack portion of the double-sided device, and the position of the side fence is manually moved to an arbitrary position. .

[0006]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a schematic configuration diagram of an image forming apparatus according to an embodiment of the present invention. The image forming apparatus includes, in addition to the image forming unit 1 and the fixing unit 2, a paper feed tray 4, a paper feed unit 5 that feeds the transfer paper one by one from the paper feed tray 4, and a transfer paper having an image formed on one side. A double-sided device 6 for forming an image on the other surface is provided. A first switching claw 8 for switching the transfer paper between the paper discharge unit 7 and the duplex device 6 is provided near the paper discharge unit 7. The double-sided device 6 has a side fence 9. The side fence 9 can be moved to an arbitrary position by a stepping motor or the like. The side fence 9 can be manually moved to an arbitrary position.
Further, a second method for switching the transfer sheet in the stack unit (described in FIGS. 2 and 3) of the double-sided device 6 to a discharge path or a double-side re-feeding path (described in FIGS. 2 and 3). There is a switching claw 10. A post-processing device 11 is provided downstream of the image forming apparatus. The post-processing device 11 performs various types of post-processing such as sorting, binding, punching, and folding on an image-formed transfer sheet discharged from the image forming apparatus.

Next, the operation will be described. First, in the normal copy mode, the transfer paper set in the paper feed tray 4 is fed one by one by the paper feed unit 5 and
After forming an image in the above, the image is conveyed to the post-processing unit 11. At this time, the first switching claw 8 has opened the paper discharge unit 7 side.

Next, in the case of the double-sided mode, the transfer paper having an image formed on its surface is directed to the double-sided apparatus 6 by switching the first switching claw 8. Hereinafter, description will be given based on FIG. FIG. 2 is an enlarged view of a main portion showing a state of the second switching claw when a re-feeded transfer sheet is transported to the image forming section. The transfer paper P conveyed to the stacking section 6a of the double-sided device 6 is moved by the call roller 12 toward the second switching claw 10 (left side in the figure).
And transported by the double-sided roller 13 and the roller 13a. At this time, the second switching claw 10 is in a state where the transfer paper P is along the peripheral surface of the double-sided roller 13, and the transfer paper P moves between the arc portion of the second switching claw 10 and the double-sided roller 13. The sheet is then reversed, enters a horizontal double-sided refeeding path 14 below the stacking section 6a, and is sent out again to the image forming section 1 where the image is transferred to the back side by the image forming section 1 and fixed. The image is fixed in the section 2. Then, the position of the first switching claw 8 is switched before the transfer paper P arrives, and the transfer paper P on which images are formed on both sides is sent to the post-processing unit 11 via the paper discharge unit 7.

Next, the slip sheet mode will be described. FIG. 3 is an enlarged view of a main part showing a state of the second switching claw when a re-feeded transfer sheet is transported to a post-processing device. When performing the interleaving work, when the interleaving function is selected by the operation unit or the like and the interleaving paper size is set, the side fence 7 of the duplex apparatus 6 moves according to the size. A mechanism capable of setting a sheet is provided in the stacking section of the double-sided device. The double-sided device 6 is pulled out toward the user, and the slip sheet is set in the stacking portion 6 a of the double-sided device 6. When the interleaf copy is started, the transfer sheet, which is sent out from the paper feed tray 4 to the image forming unit 1, forms an image in the image forming unit 1, and is conveyed to the post-processing device 11, needs a necessary timing (normal copy paper). The interleaving paper is fed from the double-sided device 6 at the timing of inserting the interleaving paper, and the interleaving paper is directly conveyed to the post-processing device 11 by the second switching claw 10 to perform the interleaving operation. It goes without saying that normal copying is interrupted while the slip sheet work is being performed.

This situation will be described in more detail. When the slip sheet P1 is set in the stacking section 6a of the duplex device 6 and the slip sheet mode is started, the call roller 12 is lowered, and the slip sheet P1 is called in the direction of the second switching claw 10 (leftward in the figure). At this time, the second switching claw 10 is switched to a position where the slip sheet P1 is directed obliquely upward without following the peripheral surface of the double-sided roller 13. As a result, the slip sheet P1 enters a slip sheet discharge path 15 that continues to the discharge section 7. Interleaf paper discharge path 15
Has a plurality of transport roller pairs 16 and 17, and
Is transported obliquely upward by these transport roller pairs 16 and 17 and reaches the paper discharge unit 7 where the post-processing device 1
Handed over to 1. As described above, in the slip sheet mode, the slip sheet P1 does not pass through the fixing unit 2, so that even if the target image forming apparatus is a black-and-white machine and the slip sheet P1 is a color image formed, the toner The aforementioned disadvantages due to melting do not occur.

Although the interleaf size is set after selecting the interleaf function, the side fence 7 of the double-sided device 6 may move according to the size of the transfer paper in the selected paper feed tray. . In the case where the size of the slip sheet is irregular, for example, after the double-sided device 6 is pulled out, the side fence 7 is manually moved to an arbitrary position. It is regulated by the side fence 7. Further, the image forming apparatus according to the present invention can be applied even if the post-processing section is provided outside or the post-processing section is built-in.

In the above-described embodiment, the transfer paper is fed and fed from the paper feed tray 4, an image is formed in the image forming unit 1, and then the paper is transferred to the post-processing device 11.
After the front side image is formed, the sheet is once stacked on the double-sided device 6 and re-fed, and then re-fed from the double-sided device 6 in the image forming apparatus having a path for forming an image on the back surface in the image forming unit 1 again. By switching the second switching claw 10 as shown in FIG. 3 to switch the conveyance path, the image forming unit 1 (fixing unit 2)
A mechanism (second switching claw 10, double-sided roller 13) that is not conveyed to the post-processing device 11 and is capable of setting a sheet on the stacking portion 6a of the double-sided device 6. And has a slip sheet function for inserting a slip sheet between transfer sheets on which images are formed, and when the slip sheet function is selected, an image is formed from the sheet feed tray 4 and a post-processing device is formed. 11
The interleaf paper is fed from the double-sided device 6 to the transfer paper conveyed to the necessary timing, and the interleaving process is performed. Since the interleaving operation can be performed without passing through the (fixing unit), even if special paper is used as interleaving paper, it is possible to prevent problems such as fixing offset and fixing wound jam. In addition, by using the double-sided device 6 and the interleaf tray together, the size and cost of the device can be reduced.
In the embodiment, the stack unit 6 of the double-sided device 6 is used.
a is provided with a side fence 9, and by setting the paper size of the interleaf, the side fence 9 is moved in accordance with the size of the interleaf by a driving means such as a motor.
By setting the size of the slip sheet, the stack portion 6a of the duplex device 6
Side fence 9 moves in accordance with the size of the slip sheet, so that the lateral registration deviation and skew of the slip sheet can be prevented. In the above embodiment, the side fence 9 is provided in the stacking section 6a of the duplex apparatus 6, and after selecting the interleaving function, the side fence 9 is adjusted according to the size of the transfer paper of the selected paper feed tray 4. Is moved in accordance with the size of the transfer paper by a driving means such as a motor. Therefore, when the interleaving function is selected, the side of the stack unit 6a of the duplex unit 6 is set by setting the transfer paper size of the selected paper feed tray 4. Since the fence 9 moves in accordance with the size of the slip sheet, it is possible to prevent the lateral registration deviation and the skew of the slip sheet. In the above-described embodiment, the stacking portion 6a of the double-sided device 6 is provided with the side fence 9, and the position of the side fence 9 is manually moved to an arbitrary position. In addition, it is possible to prevent lateral slippage and skew of the slip sheet.

[0013]

According to the first aspect of the invention, a slip sheet can be set in the stack section of the double-sided apparatus and the slip sheet can be performed without passing through the image forming section 1 (fixing section). Even when a suitable sheet is used as a slip sheet, it is possible to prevent problems such as fixing offset and jam with fixing winding. In addition, by using the double-sided device and the interleaf tray together, it is possible to reduce the size and cost of the device. According to the second aspect of the present invention, the side fence of the stack portion of the duplex apparatus moves in accordance with the size of the slip sheet by setting the size of the slip sheet, so that misregistration and skew of the slip sheet can be prevented. . According to the third aspect of the present invention, the side fence of the stack unit of the duplex apparatus moves according to the size of the slip sheet by setting the transfer sheet size of the selected sheet feeding tray when the slip sheet function is selected. It is possible to prevent misalignment and skew of the lateral registration of the slip sheet. According to the fourth aspect of the present invention, the side fence of the stack portion of the double-sided device is moved by the user to an arbitrary position, so that the slip of the lateral registration of the slip sheet and the skew can be prevented even for slip sheets of irregular size. Can be prevented.

[Brief description of the drawings]

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

FIG. 2 is an enlarged view of a main part showing a state of a second switching claw when a re-feeded transfer sheet is transported to an image forming unit.

FIG. 3 is an enlarged view of a main part showing a state of a second switching claw when a re-feeded transfer sheet is transported to a post-processing device.

FIG. 4 is a schematic configuration diagram of an image forming apparatus having a slip sheet function according to a conventional example.

[Explanation of symbols]

 REFERENCE SIGNS LIST 1 Image forming unit 2 Fixing unit 4 Paper feed tray 5 Paper feed unit 6 Double-sided device 6a Stack unit 7 Paper discharge unit 8 First switching claw 9 Side fence 10 Second switching claw 11 Post-processing device 12 Call roller 13 Double-sided roller 14 Double-sided refeed path 15 Interleaf paper discharge path 16, 17 Transport roller pair

Claims (4)

[Claims] A transfer path for feeding the transfer paper from a paper feed tray, forming an image in an image forming unit, and then conveying the transfer paper to a post-processing unit;
In the image forming apparatus provided with a path for forming an image on the back surface in the image forming unit again after re-feeding, by switching the conveyance path after re-feeding from the double-sided apparatus, the image forming unit It has a mechanism that is not conveyed and is conveyed to the post-processing unit as it is, and has a mechanism that can set paper in the stack unit of the double-sided device. When the interleaving function is selected, an image is formed from a paper feed tray and the transfer paper conveyed to the post-processing unit is provided with the interleaving function at a necessary timing. An image forming apparatus, wherein a slip sheet is fed from the apparatus and a slip sheet process is performed. 2. The image forming apparatus according to claim 1, wherein a stack portion of the double-sided device includes a side fence.
An image forming apparatus wherein the side fence is moved in accordance with the size of the slip sheet by setting a sheet size of the slip sheet by a driving unit such as a motor. 3. The image forming apparatus according to claim 1, wherein a stack portion of the double-sided device includes a side fence.
The image forming method according to claim 1, wherein after the interleaving function is selected, the side fence is moved in accordance with the size of the transfer paper by a driving unit such as a motor in accordance with the size of the transfer paper in the selected paper feed tray. apparatus. 4. The image forming apparatus according to claim 1, wherein a stack portion of the double-sided device includes a side fence,
An image forming apparatus, wherein the position of the side fence is manually moved to an arbitrary position.