JPH0692529A - Sheet conveyor device for image forming device - Google Patents

Abstract

PURPOSE:To feed special paper such as thick paper, stored in an uppermost paper supply tray, through separately provided carrier paths with large curvature in an electrophotographic copying machine constituted in such a way that nemerous trays provided at a paper supply part can be pulled out onto the front side of a device. CONSTITUTION:A sheet carrier path 13 is disposed at the side part of an electrophotographic copying machine, and the sheet carrier path 13 is provided with mechanism for conveying sheets fed from a paper feeder 12. A register part 16 is disposed downstream of the sheet carrier path 13 to cope with the transfer of images from a photoconductor drum 5. A branch guide device 21 is disposed between the sheet carrier path 13 and the register part 16, and three sheet paths 14, 22, 23 are provided in the branch guide device 21. Thick paper or the like fed from an uppermost paper supply tray 10 is delivered to a vertical path 24 through the sheet path 22 and delivered in the reversed state toward the register part 16 through the upper sheet path 23. The sheet is thus fed through the carrier paths with large curvature.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet conveying device in an image forming apparatus, and more particularly, when a thick paper or the like is accommodated in a paper feeding tray arranged at the top of a paper feeding portion, the thick paper or the like is directly curved. The present invention relates to a sheet conveying device of an image forming apparatus that enables the sheet to be sent out through a sheet path having a large bending radius without being sent to the registration section via the sheet.

[0002]

2. Description of the Related Art Like electrophotographic copying machines and printers,
2. Description of the Related Art In an image forming apparatus that creates a recording sheet using an electrophotographic method, an image carrier such as a photosensitive drum is arranged on the upper part of the apparatus main body, a toner image formed on the photosensitive drum is transferred to a sheet, and the sheet is transferred. Is fixed through a fixing device to form a copy. In the general image forming apparatus, as shown in, for example, Japanese Patent Laid-Open No. 4-3735, a paper feeding unit equipped with a large number of paper feeding trays is arranged at the bottom of the apparatus main body. Then, the paper fed from the paper feed tray is conveyed through a paper conveying path arranged on the side of the apparatus main body, and is aligned by a resist portion arranged immediately before the image transfer portion from the photosensitive drum. A mechanism for feeding the toner image formed on the photosensitive drum is provided in a state where the timing is matched with the toner image.

The electrophotographic copying machine is constructed as shown in FIG. 4, in which a platen 2 is arranged on the upper part of the main body of the electrophotographic copying machine 1, and an optical scanning device 3 is arranged below the platen 2. It is arranged. Further, the photoconductor drum 5 is arranged corresponding to the scanning device, and a mechanism such as a developing device and a cleaning device is arranged corresponding to the photoconductor drum, similarly to a device using a general electrophotographic system. ing. Then, the image of the original document set on the platen 2 is scanned by the optical device 3, information of the original document is transmitted to the photosensitive drum, a toner image is formed by using an electrophotographic method, and the toner image is transferred by a transfer corotron. A mechanism for transferring to paper by the discharge from 6 is provided.

At the bottom of the main body of the electrophotographic copying machine, a plurality of paper feed trays 10, 10a, ... And an intermediate tray 1 are provided.
1 and 1 are arranged in a vertically stacked state, and their paper feed trays are provided on the front side of the apparatus main body so that they can be pulled out. Further, for each of the paper feed trays 10, 10a ... And the intermediate tray 11, paper feed devices 12, 12a are provided.
.. are respectively arranged, and the paper paths from the paper feeding devices are connected to the paper conveyance path 13 arranged vertically on the side of the apparatus main body. At the downstream of the paper transport path 13, a registration unit 16 is arranged immediately in front of the image transfer section from the photoconductor drum to align the paper transported in the paper transport path 13 and It is made to correspond to the transfer of the image from.

The sheet on which the toner image has been transferred by the discharge of the transfer corotron 6 at the image transfer portion of the photosensitive drum 5 is fixed through the fixing device 7 and discharged onto the discharge tray 8. In the case of double-sided copy or multiplex copy, the sheet created as a single-sided copy sheet is accommodated in the intermediate tray 11 via the return path 9 and is fed from the intermediate tray toward the backside copy or multiplex copy. The device 12c is used for delivery. In addition to the configuration of the paper feed path, in the electrophotographic copying machine 1, a manual feed tray 15 is arranged on the side of the main body of the apparatus, and the paper fed from the manual feed tray 15 is fed to the paper just before the registration unit 16. It joins the transport path so that thick paper or special-sized paper can be fed.

[0006]

In the electrophotographic copying machine configured as described above, for example, a postcard or an OH
It is difficult to feed special paper such as P film depending on the paper feeding device arranged in the paper feeding tray. Therefore, the special paper as described above is fed through the manual feed tray. However, since the manual feed tray is required to be provided on the side portion of the apparatus main body in a state of largely protruding, there is a problem that an extra space is required on the side portion of the apparatus. Further, when the manual feed tray is not used, it can be held in a state of leaning against the side portion of the apparatus main body, but since it needs to be opened to the state shown in the drawing when used, extra labor is required for the operator. The problem of hanging up remains.

In order to solve the above-mentioned problems, the uppermost one of a plurality of paper feed trays provided in the paper feed unit is configured to be capable of accommodating special paper such as thick paper. It is considered that the sheet feeding device provided in the above is configured as a mechanism capable of feeding thick paper or the like. However, in the uppermost paper feed tray, it is necessary to join the paper path from the paper feed device to the curved path at the upper part of the paper transport path, and as shown in the figure, it has a substantially U-shape with a small radius of curvature. It is necessary to guide the paper toward the registration portion via the curved path. However, transporting thick paper such as a postcard through a path having a small radius of curvature causes a problem such as a jam, and there is a problem that it cannot be easily used in a conventional electrophotographic copying machine or the like. .

[0008]

SUMMARY OF THE INVENTION The present invention solves the above-described problems of the sheet conveying device in the image forming apparatus, and extends upward from the sheet conveying path perpendicular to the curved path at the upper end of the sheet conveying path. By arranging a vertical path and a paper path that joins from the middle of the vertical path to the immediately preceding portion of the registration section, and forming a branch guide device, it is difficult to bend cardboard such as thick paper from the uppermost paper feed tray. A first object of the present invention is to provide an apparatus capable of feeding a sheet in a state of reversing the sheet through a vertical path when the sheet is sent out, and configuring the vertical path as a manual sheet feeding apparatus. The purpose is.

[0009]

SUMMARY OF THE INVENTION According to the present invention, a paper path from each paper feed tray is connected to a substantially vertical paper conveyance path arranged on a side portion of the apparatus main body, and the registration path is provided via a curved conveyance path. The present invention relates to an image forming apparatus that conveys a sheet to a transfer unit.

In the paper transporting apparatus of the present invention, a substantially vertical path extending upward from the vertical transport path on the side of the main body with respect to the curved transport path, and a path for merging from the middle of the vertical path toward the registration section. And a branch guide device in which these three transport paths are combined, and branch gate means is disposed in the branch portion, and a sheet fed from a sheet feeding tray disposed in the sheet feeding portion is provided. Is configured so that it can be conveyed toward the image transfer portion by arbitrarily selecting two conveyance paths.

Further, according to the present invention, an extension of the substantially vertical path in the branch guide device is configured as a manual sheet feeding device, and the manual sheet feeding device is vertically arranged at a side portion of a machine body to form a sheet. Can be configured to be capable of feeding. Further, in the present invention, a swingable gate member is arranged at a branch portion between the vertical path and the curved path, and an elastic body is configured at a branch portion from a path extending from the vertical path to the resist section. By disposing the guide member and the forward / reverse drive roller member,
It is possible to configure a unit that guides the sheet moved from the upper portion of the vertical path toward the branch guide device toward the registration unit.

As described above, U at the upper part of the paper transport path
By arranging the branch guide device for the letter-shaped conveyance path and arranging the mechanism that feeds the thick paper fed from the upper paper feed tray in the state of being reversed through the path having a large curvature. The top paper feed tray can be used instead of the manual feed tray. Further, when the vertical path provided in the branch guide device is configured as a manual sheet feeding device,
A mechanism for feeding one special size sheet or the like can be configured. Then, instead of providing the manual feed tray with a large protrusion on the side portion of the apparatus body, by providing the manual feed device vertically on the side portion of the apparatus body,
An image forming apparatus that does not require an extra space on the side of the apparatus can be configured.

[0013]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A sheet conveying device of an image forming apparatus of the present invention will be described with reference to the illustrated example. In the embodiment of the present invention shown in FIG. 1, an apparatus having a mechanism substantially similar to the electrophotographic copying machine shown in FIG. It shows a mechanism for changing the configuration of the paper transport path to and from the unit. In the example shown in FIG. 1, paper feed paths from a plurality of paper feed trays are connected to a paper feed path 13 arranged on the side of the main body of the electrophotographic copying machine, and paper fed from each tray is fed. ,
The sheet is conveyed toward the registration section 16 via the sheet conveying path 13. Then, the pre-registration roller device 16a provided in the registration section 16 and the registration roller device 16b are provided with a sheet aligning action to transfer the image from the photosensitive drum 5.

Further, the sheet feeding device 12 arranged on the sheet feeding tray 10 is the same as the conventional sheet feeding device.
It is composed of a nudger roller 17 which is pressed against the paper P placed on the tray, and a paper separating mechanism which is arranged in the downstream portion thereof. In the paper separating mechanism, the paper feed roller 18 and the retard roller 19 are arranged so as to face each other, and the paper is separated between the two rollers so that only one sheet of paper is conveyed to the paper conveying path 13.
It constitutes a means for carrying toward.

In the paper carrying device of the present invention, a branch guide device 21 is provided between the vertical part of the paper carrying path 13 and the registration part 16. The branch guide device 21 includes an ascending path 22 that extends the upper part of the paper transport path 13 toward the vertical path 24, an upper paper path 23 that is arranged from the lower part of the vertical path 24 toward the registration unit 16, and a paper transport path. A lower sheet path 14 which is formed as a curved path between 13 and the resist portion is formed by combining three sides of a triangle.
Then, with respect to the branch guide device 21, the paper transport path 1
The transport roller device 27 is disposed at the upper end of the vertical path 24.
A forward / reverse drive roller device 28 is arranged in the lower part of the.

Further, in the branch guide device 21, a branch gate member 25 is arranged at a branch portion between the lower paper path 14 and the ascending path 22, and the gate member 25 is rocked by using a driving means such as a solenoid. It constitutes a means for guiding the sheet toward two paths. Further, a guide member 26 formed of an elastic film member (for example, Mylar ... product name) is arranged at the confluence of the two paper paths 22 and 23 connected to the vertical path 24. Then, when the paper is lifted from the ascending path 22 toward the vertical path 24, the guide member 26 is curved as shown by the chain line, but the paper is moved from the vertical path 24 to the lower part. When the sheet is fed, the sheet is passed through the upper surface of the guide member 26 and the upper sheet path 2
You can guide to 3.

The sheet conveying path configured as described above can be simplified as shown in FIG. Therefore, the operation of the sheet conveying device in the apparatus of the present invention will be described according to the sheet conveying path shown in FIG. First, in the paper transporting device of the present invention, paper such as plain paper passes from the paper feed tray through the paper transporting path 13 to the lower paper path 14 and is aligned by the registration unit 16 to be removed from the photosensitive drum 5. The toner image is transferred toward the transfer portion. In the case of making a copy using the plain paper, even when the paper is sent from the uppermost paper feed tray 10 of the paper feed unit, a very small curve is formed from the paper path of the paper feed device 12 corresponding to the tray. The sheet can be fed toward the registration unit via the conveyance path 14 having a radius. Further, as described above, when making a copy using plain paper, the gate member 25 is held at the position where the ascending path 22 is closed, so that the electrophotographic copying machine can be kept in the normal copy mode. , Make the copy operation.

On the other hand, when a thick paper or the like is placed on the paper feed tray 10 arranged at the top of the paper feed unit, the special paper such as the thick paper or the like is sent to the control device of the copying machine. Enter the information about feeding. Further, the paper feed tray 1
When thick paper is fed from 0, the switching gate 25 is operated in response to the feeding signal to set the state in which the paper transport path 13 and the ascending path 22 are connected. Then, when the paper is sent out from the paper feed tray 10, the paper is transported by the transport roller device 27, rises in the ascending path 22, and when the sensor S detects the leading end of the paper, the paper is placed on the upper portion. The forward / reverse driving roller device 28 is driven in a direction of raising the paper toward the vertical path 24 to perform a paper conveying operation.

As described above, when the sheet is accommodated in the vertical path 24, the roller device 28 is stopped by the detection information of the trailing edge of the sheet, and the roller device 28 is stopped after a predetermined time has elapsed. It is driven in reverse. Then, the sheet is guided by the roller device 28 through the upper surface of the guide member to the upper sheet path 23, and is conveyed toward the registration section 16,
A matching action is performed in the resist portion. Therefore, in the paper transporting device of the present invention, the paper branch guide device 21 is provided only when the thick paper or the like is stored in the uppermost paper feed tray of the paper feed unit and the information is input to the control device.
It is possible to use a means for transporting it through the reversing path.

Further, in the branch guide device 21,
The vertical path 24 can be configured as a manual sheet feeding device that is arranged substantially vertically. Then, by inserting the sheets one by one into the manual sheet feeder, the sheets are conveyed by using the forward / reverse drive roller device 28, and the upper sheet path 23 is conveyed.
It can be sent toward the resist portion 16 via. In addition, as described above, the manual feeding device is installed in the vertical path 2
In the case of configuring a mechanism for connecting to the No. 4, the manual paper feeding device can be configured as a vertical type so as to be along the side part of the device main body as shown in FIG. .

In the electrophotographic copying machine 1 shown in FIG. 3, the manual paper feeding device 20 in a substantially vertical state is arranged on the side portion of the main body of the device, as described above, and the manual paper feeding device in a general image forming apparatus is provided. It is used when making copies using non-standard size paper such as trays and non-standard size paper, or special paper. Further, special papers such as postcards and OHP films can be stored in any of a plurality of paper feed trays arranged at the bottom of the apparatus body.
Then, all of the plurality of paper feed trays arranged in the paper feed section of the electrophotographic copying machine are provided so as to be able to be drawn out in front of the apparatus, and operations such as replenishment of paper to each tray can be performed from the front side. Such a mechanism can be configured.

Therefore, in the electrophotographic copying machine constructed as shown in FIG. 3, even when the manual paper feeding device 20 is provided, the manual paper feeding device is erected substantially vertically on the side portion of the apparatus main body. In this case, no extra space is required on the side of the copying machine and the floor area occupied by the copying machine is not required to be large. Furthermore, even when replenishing paper to the paper feed tray,
Since it is provided on the front side of the apparatus so that it can be pulled out, it is possible to maintain the same operability as in the case of the conventional electrophotographic copying machine.

As described above, when arranging the branch guide device in the upper part of the paper transport path, for any one of the plurality of paper feed trays arranged in the paper feed section, a cardboard or the like is used. It is possible to store various special papers. Also,
If special paper is stored in the paper tray,
It is necessary to input the information to the control device of the electrophotographic copying machine.As an input method, a set button is provided on the control panel, and the operator pushes the button, or the like. A selection operation can be performed. Further, when one of the paper feed trays arranged in the paper feed section of the electrophotographic copying machine is set as a tray for special papers, the paper fed from the paper feed tray is It is also possible to configure a mechanism in which all of them are inverted via the branch guide device and conveyed toward the image transfer portion.

[0024]

Since the sheet conveying device of the image forming apparatus of the present invention is configured as described above, the branch guide device is arranged with respect to the U-shaped conveying path above the sheet conveying path. However, by arranging a mechanism that feeds thick paper, etc. fed from the upper paper feed tray in a state of being reversed through a path having a large curvature, the uppermost paper feed tray is used instead of the manual feed tray. Can be used. Further, when the vertical path provided in the branch guide device is configured as a manual sheet feeder, a mechanism for feeding one special size sheet or the like can be configured. Then, by installing the manual paper feeding device in a vertical state on the side part of the device main body,
It is possible to configure the image forming apparatus in which the manual sheet feeding device does not largely protrude to the side portion of the apparatus main body and does not require an extra space on the side portion of the apparatus.

[Brief description of drawings]

FIG. 1 is a side view showing a configuration of a sheet conveyance path provided in an electrophotographic copying machine of the present invention.

FIG. 2 is an explanatory view showing a simplified paper conveyance path of FIG.

FIG. 3 is a perspective view of an electrophotographic copying machine that can be equipped with the sheet conveying apparatus of the present invention.

FIG. 4 is an explanatory diagram showing a configuration of a conventional electrophotographic copying machine.

[Explanation of symbols]

1 Electrophotographic copying machine, 5 Photosensitive drum, 8
Ejection tray, 10 paper feeding tray, 12 paper feeding device, 13 paper transport path, 14 lower paper path, 15
Manual feed tray, 16 registration unit, 20 manual feed device, 21 branch guide device, 22 ascending path, 23 upper paper path, 24 vertical path, 25
Branch gate, 26 guide member, 27 transport roller device, 28 forward / reverse drive roller device.

Claims (3)

[Claims] 1. An image forming apparatus in which a paper path from each paper feed tray is connected to a substantially vertical paper conveyance path on a side portion of an apparatus main body and is conveyed to a registration section and a transfer section via a curved conveyance path. With respect to the curved transport path, a substantially vertical path extending upward from the vertical transport path on the side of the main body and a path for merging from the middle of the vertical path toward the resist portion are provided, and three of these are provided. In addition to being configured as a branch guide device that combines transport paths, branch gate means is disposed in the branch portion, and two paper paths can be arbitrarily selected from among the paper sheets fed from the paper feed tray arranged in the paper feed portion. Then, the sheet conveying device of the image forming apparatus is configured so that it can be conveyed toward the image transfer portion. 2. An extension portion of a substantially vertical path in the branch guide device is configured as a manual sheet feeding device, and the manual sheet feeding device is vertically arranged at a side portion of a machine body to feed a sheet. The sheet conveying device of the image forming apparatus according to claim 1, wherein the sheet conveying device is configured to obtain. 3. A swingable gate member is arranged at a branch portion between the vertical path and the curved path, and a guide member made of an elastic body is provided at a branch portion from a path extending from the vertical path to the registration section. 2. A means for guiding the sheet, which is moved from the upper part of the vertical path toward the branch guide device, toward the registration portion by disposing the forward and reverse drive roller members. Paper transport device for image forming device.