JPH06211364A - Paper feeder for image forming device - Google Patents

Abstract

PURPOSE:To produce a copy by receiving paper of small size to the front/rear relating to a tray, to which paper of large size can be received, and feeding the paper of two kinds arbitrarily in a longitudinal direction of the tray. CONSTITUTION:In an electrophotographic copying machine 1, relating to a paper feed tray 20 arranged in a paper feed part, a paper feed member by paper feed rollers 30, 30a is arranged in the front/rear of this paper feed tray, so that paper can be fed toward a paper conveying path 10 and a return path 12 through paper feed paths 31, 31a. The paper fed toward the return path 12 is fed toward the paper conveying path 10 through an intermediate tray 32, and the paper is fed toward an image transcribing part from a sensitized drum 2 through an ordinary paper conveying system. Also relating to the other paper feed trays 35, 35a... arranged in the paper feed part of the electrophotographic copying machine, a mechanism, by which paper can be fed from both sides, is arranged, and a tray capable of receiving paper of small size in two kinds can be obtained.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding means in an image forming apparatus such as a copying machine capable of feeding a large size sheet such as a drawing from a sheet feeding tray to make a large size copy.
In particular, an image forming apparatus capable of making copies by accommodating two kinds of small-sized sheets before and after the large-sized sheet feeding tray and arbitrarily feeding the sheets from the front and rear portions of the tray. Regarding

[0002]

2. Description of the Related Art In an image forming apparatus such as an electrophotographic copying machine or a printer, a paper feeding unit is equipped with a plurality of paper feeding trays, and the paper quality differs from those paper feeding trays. It is configured to accommodate paper of different sizes. Then, the size of the original set on the image reading device,
Paper of an arbitrary size can be fed according to information such as a reduction ratio input via the control panel. In the image forming apparatus as described above, for example, as shown in Japanese Unexamined Patent Publication No. 3-267255, an apparatus of a type in which a large number of sheet feeding trays are provided in a sheet feeding section is used. Then, the paper sent out from the paper feed tray is sent out through a paper conveyance path vertically arranged on one side of the paper feed unit, the image from the photoconductor drum is transferred, and the image is fixed through a fixing device to be fixed and copied. It constitutes a mechanism for discharging as.

In the above-mentioned conventional image forming apparatus, in order to make a double-sided copy or a multiplex copy, a sheet prepared as a single-sided copy sheet through a fixing device is accommodated toward an intermediate tray through a return path, and then the reverse side or the composite sheet. It is designed to be sent out again for copying. As described above, in a paper feeding unit equipped with a paper feeding tray capable of accommodating a plurality of papers of different sizes, a paper feeding roller or the like arranged for each paper feeding tray is arranged in one of the paper feeding units, The paper sent out from each tray can be sent out toward the paper transport path. Further, in the image forming apparatus configured as described above, each tray is configured so as to be capable of accommodating the maximum size sheet used in the image forming apparatus. For example, as shown in FIG. In addition, in a copying machine or the like that can use a large size sheet, all trays are configured to be capable of accommodating the maximum size sheet.

[0004]

However, even in the image forming apparatus as described above, the maximum size of only one or a half or less of the plurality of paper feed trays arranged in the paper feed unit is provided. Other trays generally accommodate small size sheets such as A4 size and B5 size. Therefore,
In a tray capable of accommodating a large size sheet, only a part of the effective space of the tray is used, and the other spare space is wasted. Further, in a large-sized electrophotographic copying machine or the like capable of making a large-sized copy, a relatively large-sized paper is frequently used, but a small-sized paper is rarely used. However, since the paper that is rarely used is set in the paper feed section while being accommodated in the paper feed tray, the tray that accommodates the small size paper naturally occupies a certain space in the paper feed section. There is.

Therefore, in order to solve the above problems, for example, as shown in Japanese Utility Model Laid-Open No. 59-140240, a means for mounting two kinds of sheets on one tray is used. Can be considered. In the tray of the conventional example, as compared with the sheet feeding tray corresponding to the A3 size,
Small size sheets such as A4 and B5 sizes are stored in front and rear sections. Then, according to the paper to be used for copying, the tray is turned upside down and reattached to the paper feed unit, and the paper of any size is positioned corresponding to the paper feed device and directed to the image transfer unit. Can be fed. Therefore, many kinds of paper can be stored in the paper feed section of the copying machine, and the application of the electrophotographic copying machine can be expanded.

However, in the tray capable of accommodating two kinds of papers as described above, although two kinds of papers can be accommodated in the tray, when the paper is used, the paper feed tray is mounted. I need to fix it. Therefore,
The operator needs to remove the heavy tray from the paper feeding unit and reattach it, which causes a problem that the attachment work becomes a burden. Further, when a small number of small-sized sheets are used, there arises a problem that the tray is frequently replaced. In addition to the above-described problems, the return path of the image forming apparatus is provided with a transport roller device similar to the paper transport path, and is used only when performing multiplex copying or double-sided copying. However, the transport roller device arranged in the return path is not frequently used, but the performance of the transport roller device is similar to that of the paper transport path so that the paper transport performance can be sufficiently exhibited. There is a problem that such transport roller devices are rarely used effectively.

[0007]

It is an object of the present invention to solve the above-mentioned problems of the conventional paper feeding device, and to provide a mechanism for feeding paper to a paper feeding tray for storing two kinds of paper from the front and rear of the tray. By using the mechanism that sends out the paper that has been placed and is sent from the paper feed device that is placed on the rear side toward the paper transport path via the return path and the intermediate tray, it is possible to save the trouble of re-installing the tray and to copy the paper. While improving the creation efficiency,
It is an object of the present invention to provide a device that can effectively use the space of a copying machine.

[0008]

According to the present invention, it is possible to make a copy by using a large-sized sheet, and a sheet containing member such as a plurality of sheet feeding trays is arranged in the sheet feeding section. The present invention relates to an image forming apparatus configured to be able to feed paper from any of the above. In the present invention, at least one of the plurality of paper feed trays arranged in the paper feed unit is configured to be capable of feeding paper from both sides of the tray,
The sheet feeding path is connected to the sheet conveying path of the image forming apparatus and the reversing path so as to correspond to the sheet feeding tray that can feed from both sides, and the sheet fed through the reversing path is returned. It is configured so that it can be fed to a sheet conveyance path via a path such as a path and can be fed toward the image transfer section. Further, in the present invention, the paper feed tray configured to be able to feed paper from both sides is a paper storage unit capable of storing paper that is half the size or smaller than the maximum size of the paper that can be used in the image forming apparatus. Are arranged in the front and rear, and a paper support means for moving the paper up and down, a paper positioning member, etc. are arranged in correspondence with the two paper accommodating portions, and two kinds of paper accommodated in the paper feed tray are arranged. Corresponding to the above, the paper feeding means can be arranged at the front and rear positions of the paper feeding tray in the paper feeding portion of the main body of the image forming apparatus.

As described above, the paper feed tray is mounted by constructing a device capable of accommodating two types of paper in one paper feed tray and feeding paper from the front and rear directions of these trays. There is no need to fix it, and the operator's burden can be reduced. Further, in the image forming apparatus of the present invention, since two types of sheets can be accommodated in one tray, the space of the sheet feeding section can be effectively used and the sheet can be arranged in the sheet feeding section of the image forming apparatus. It is possible to reduce the number of trays to be used and to effectively utilize the mechanism of the return path which is rarely used.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A sheet feeding device of an image forming apparatus according to the present invention will be described with reference to the illustrated example. In the electrophotographic copying machine 1 shown in FIG. 1, a photosensitive drum 2 similar to that in a general electrophotographic copying machine and a mechanism for forming a toner image on the photosensitive drum are arranged in the upper part of the apparatus main body. Then, a toner image is formed on the photosensitive drum based on image information from an image reading device (not shown), and the transfer corotron 3 is formed.
Transfer to paper by discharging. Further, a fixing device 5 is arranged downstream of the photoconductor drum via a conveying device 4, and heat and pressure are applied to a sheet carrying a toner image to make a copy, and a discharge roller 7 is provided. The sheet is discharged toward the discharge tray 8 via.

A paper feed path 10 connected from the paper feed section is arranged upstream of the image transfer section from the photosensitive drum, and a plurality of paper feed trays 20, 3 are connected to the paper feed path.
A mechanism for connecting the paper feed paths from 5, 35a, ... And carrying them through the carrying roller devices 11 provided in the paper carrying path. In addition, a return path 12 is branched through a gate 6 at an intermediate portion of the discharge path from the fixing device 5, and a conveyance roller device 13 ... A mechanism for feeding the intermediate tray 32 is provided. A reversing path 14 provided with a forward / reverse driving roller device 15 is arranged below the return path 12, and when the copy mode of the sheet is double-sided copying, one-sided copying is performed from the reversing path through the lower surface of the gate 16. A mechanism for accommodating the paper toward the intermediate tray 32 is configured.

In the paper feed section disposed between the paper transport path 10 and the return path 12, as described above, the plurality of paper feed trays 20, 35, 3 are sandwiched with the intermediate tray 32 interposed therebetween.
5a is arranged. For each tray, paper feed rollers 30, 36, 36a for feeding paper are arranged, and paper fed from the paper feed tray is fed to the paper feed path 31,
The sheet is fed toward the sheet conveying path 10 via 37, 37a .... Further, in the uppermost tray 20 of the paper feeding unit, the paper feeding roller 30a is arranged on the side opposite to the paper feeding direction by the paper feeding roller 30, and the paper feeding path 31a is connected to the return path 12. There is.

The paper fed from the paper feed tray 20 by the paper feed roller 30a is guided from the return path 12 toward the intermediate tray 32, and is conveyed by using the conveying roller device provided in the intermediate tray 32. A mechanism for sending the sheet toward the sheet conveying path 10 via the sheet feeding path 33 is configured.
Therefore, in the paper feed tray 20, two types of paper P
1 and P2 are positioned and housed in front of and behind the tray, and the paper feeding operation can be performed by using any paper feeding roller according to the information of the selected paper. It is assumed that a paper feed path using the can be configured.

The paper feed tray 20 used in the electrophotographic copying machine may have a mechanism as shown in FIGS. In the example shown in FIG. 2, in the paper storage space surrounded by the frame 21 of the paper feed tray 20, the paper storage units 22 and 22a corresponding to the two types of papers P1 and P2 are arranged. The paper regulating members are arranged corresponding to the respective units. The sheet P1 accommodated in the sheet accommodating section 22 is provided at one of the sheet feeding side leading ends.
Corresponding to the above, the snubbers 25 and 26 used as a sheet separating member are arranged, and side guides 23 and 24 that regulate both sides of the sheet and an end guide 27 that regulates the rear end of the sheet are arranged. In addition, the other sheet storage portion 22a
Similarly to the case of the sheet storage unit 22, the side guides 23a and 24a, the snubbers 25a and 26a, and the end guide 27a are arranged for the sheet P2 to be stored in. Further, as shown in FIG. 3, the bottom plates 28, 2 are used to raise the paper stored in the paper storage unit and press it against the paper feed rollers 30, 30a.
8a is swingably provided.

As a mechanism for vertically moving the bottom plates 28, 28a provided on the paper feed tray 20, any mechanism can be used like the paper feed means using the conventional paper feed tray. In addition to using the swingable bottom plate, it is also possible to use an elevator type sheet supporting means. Further, the side guides and end guides for positioning the paper with respect to the paper storage portion provided in the paper feed tray 20 can be configured so as to be movable and fixed along the bottom plate of the tray and stored. To enable the positioning effect to be exhibited in good condition for any size of paper. Further, as the paper separating member provided in the paper feeding tray, a paper separating mechanism in which a paper supplying roller and a separating roller are combined can be used without using a snubber.

In the paper feed tray of the present invention configured as described above, for example, two A4 size sheets can be arranged side by side in the front-rear direction in a tray capable of storing A3 size sheets. , In addition, A4 size and B5
It is also possible to store two types of paper of different sizes in the front and back.
Further, a large electrophotographic copying machine capable of accommodating A2 size sheets can also accommodate B4 size and A4 size sheets. As described above, in the paper feed tray configured to accommodate two types of paper, for example, a frequently used size of paper is arranged near the paper transport path, and a less frequently used type of paper is returned. By arranging it on the roadside, even when making a small number of copies, it is possible to make a copy without replacing the tray.

In the image forming apparatus of the present invention,
As shown in FIG. 1, not only the paper feed tray 20 arranged at the top of the paper feed unit is configured to be capable of double-sided paper feeding, but also any other paper feed tray arranged under the intermediate tray 32 may be used. The paper tray 35 can also be configured as a tray capable of double-sided paper feeding. When the paper feed tray arranged below the intermediate tray 32 is configured to be capable of double-sided paper feed, a paper feed roller is provided for each tray toward the paper transport path 10 and the return path 12. It is possible to configure a mechanism for arranging a paper feed path and feeding a large number of types of paper without reloading the tray. As described above, when configuring a mechanism that feeds paper from both sides to multiple paper feed trays, another paper guide path from the return path to the paper transport path is used without using the intermediate tray. A mechanism for arranging and carrying the paper can be configured.

In the case of configuring the paper feed mechanism as described above, one of the paper feed trays capable of accommodating large-sized paper sheets.
One or two accommodates the maximum size of paper, but the other paper trays can accommodate two types of paper, so the paper size to be installed in the electrophotographic copying machine. The number of types can be increased. Therefore, the number of trays can be reduced even when accommodating a large number of sizes of paper, and the limited space of the paper feed unit of the electrophotographic copying machine can be effectively used.
Further, even for the paper fed from the return path side, although the transport path is slightly longer, the copy creation work can be efficiently performed without the operator exchanging the paper with respect to the tray.

[0019]

Since the sheet feeding device of the image forming apparatus of the present invention can use the sheet feeding tray having the above-described mechanism, two types of sheets can be fed to one sheet feeding tray. By configuring the device that accommodates and can feed paper from the front and rear directions of these trays, it is not necessary to reattach the paper feed tray, and the burden on the operator can be reduced. Further, in the image forming apparatus of the present invention, since two types of sheets can be accommodated in one tray, the space of the sheet feeding section can be effectively used and the sheet can be arranged in the sheet feeding section of the image forming apparatus. It is possible to reduce the number of trays to be used, and it is possible to effectively use the paper transport mechanism of the return path, which is generally less frequently used. By accommodating a large number of types of paper in the paper feed unit, the efficiency of copy creation work can be improved.

[Brief description of drawings]

FIG. 1 is a side view showing a configuration of an image forming apparatus of the present invention.

FIG. 2 is a plan view of the paper feed tray of the present invention.

FIG. 3 is a side view of the paper feed tray of FIG.

[Explanation of symbols] 1 electrophotographic copying machine, 2 photoconductor drums, 5
Fixing device, 10 paper feed path, 12 return path,
20 paper feed trays, 22 paper storage units, 23
24 side guides, 25/26 snubbers, 2
7 End guide, 28 Bottom plate, 30
Paper feed roller, 31 paper feed path, 32 intermediate tray, 35 / 35a paper feed tray, 36 paper feed roller, 37 paper feed path.

Claims (2)

[Claims] 1. A copy can be made using a large size paper, and a paper storage member such as a plurality of paper feed trays is arranged in a paper feed unit, and paper can be fed from any one of the paper feed trays. In the image forming apparatus configured as described above, at least one of a plurality of paper feed trays arranged in the paper feed unit is configured to be able to feed paper from both sides of the tray, and can feed paper from both sides. Corresponding to the paper feed tray, the paper feed path is connected to the paper conveyance path and the reversal path of the image forming apparatus, and the paper fed through the reversal path is fed through the path such as the return path. A sheet feeding device of an image forming apparatus, which is configured so that it can be fed to a sheet conveying path and can be fed toward an image transfer section. 2. A paper feed tray configured to feed paper from both sides has a front and rear paper storage unit capable of storing paper of a size equal to or less than half of a maximum size of paper usable in an image forming apparatus. Corresponding to the two paper accommodating portions, a paper supporting unit for moving the paper up and down, a paper positioning member, and the like are arranged to accommodate two kinds of paper accommodated in the paper feed tray. 2. The sheet feeding device of the image forming apparatus according to claim 1, wherein the sheet feeding unit is arranged at a position before and after the sheet feeding tray in the sheet feeding unit of the main body of the image forming apparatus.