JPH04317930A - Sheet feed guide device of image forming apparatus - Google Patents

Abstract

PURPOSE:To increase the rigidity of a passage for sheet from a sheet feeder cassette and simplify the structure of this sheet feeding passage. CONSTITUTION:A sheet feeder cassette 17 is installed in the lower part of an image forming part 4, and a sheet feeding device 21 of large size is provided at the side of the body 1. Thus an image forming device is constructed, in which sheet guides 20 furnished on the body 1 side are positioned oppositely to the side face 27 of the sheet feeding device 21 to form a sheet feeding passage 28, and thereby the number of sheet guides is lessened and the supporting structure thereof is simplifed. The side face 27 of the sheet feeding device 21 has a higher rigidity than sheet guide, so that the supporting strength for transport roller 30 is increased and the contact pressure of transport rollers 29, 30 in a couple is maintained over a certain level, which should lessen occurrence of the sheet remaining out of being fed and also generation of jam or the like.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paper feed guide device for an image forming apparatus.

0002

2. Description of the Related Art Conventionally, as described in Japanese Unexamined Patent Publication No. 2-110039, a plurality of paper feed cassettes are arranged below the main body of an image forming apparatus, and one of these paper feed cassettes is Some image forming apparatuses feed paper from the top to the image forming apparatus above, and when the number of copies is large, the paper is fed from a large paper feeder installed on the side of the main body of the apparatus. .

0003

[Problem to be solved by the invention] JP-A-2-11003
The image forming apparatus described in Publication No. 9, in which the paper cassette is located below the main body of the apparatus, is generally referred to as a front loading type, and replenishing paper to the paper cassette is carried out from the main body of the apparatus. This is done from the front of the paper feed cassette, which can contribute to reducing the installation space of the main body of the device. However, with this type of front loading, the total length of the paper feed path that extends upward from the paper feed cassette is long, and this feed Requires long pairs of paper guides to form the paper path. In addition, the conveyance rollers that convey paper are held by paper guides, but a long paper guide means that the rigidity of the paper guide is insufficient, so the contact pressure between the pair of conveyance rollers decreases and the paper is conveyed. Power decreases. As a result,
Paper misfeeds, jams, etc. occur. Although there is a method of dividing the paper guide, this method increases the number of paper guides, complicates the structure for individually supporting them, and increases cost.

Furthermore, since the paper feed path is long, it is troublesome to clear the paper jam, and in order to open the paper feed path, it is necessary to increase the distance between the paper feed path and the large paper feed device. The amount of protrusion of the large paper feeder from the main body increases,
It cannot meet the demand for space saving. Also,
The large paper feed device attached to the side of the main body of the device feeds paper from the side.When replenishing paper to this large paper feed device or replacing paper of different sizes, it is necessary to It is easier to operate if you go around from the front to the side. However, opening a work space on the side of the apparatus body for this purpose goes against the demand for space saving.

[0005]

[Means for Solving the Problems] The invention as claimed in claim 1 provides an image forming section, a paper feed cassette disposed below the image forming section, and a paper feed cassette directed toward the image forming section from the leading end of the paper feed cassette. a paper guide extending in the vertical direction, a large paper feeder having side surfaces facing each other with a predetermined gap between the paper guide, and a paper guide formed between the paper guide and the side surface of the large paper feeder. It consists of a paper feed path.

According to a second aspect of the present invention, in the first aspect, a fulcrum portion is provided near one side of the rear side of the paper guide for rotatably holding the large paper feeding device about a vertical rotation axis.

The invention according to claim 3 is the invention according to claim 1, in which a large paper feeding device is rotatably held with a vertical rotation axis in the vicinity of one side on the back side and one side on the front side of the paper guide. A fulcrum part was provided for the purpose.

[0008]

[Operation] According to the invention as claimed in claim 1, the side surface of the large paper feeding device can also be used as one paper guide of a pair of paper guides for forming a paper feeding path, thereby reducing the number of paper guides. It is possible to reduce the number of paper guides and to simplify the support structure that supports the paper guide. In addition, since the side surfaces of the large paper feeder have higher rigidity than a single paper guide, it is possible to increase the support strength of the transport rollers and maintain the contact pressure between the pair of transport rollers above a certain level. It is possible to reduce the occurrence of paper misfeeds, paper jams, and the like.

[0009] According to the second aspect of the invention, by rotating the large paper feed device around the fulcrum, the paper feed path can be widened toward the front, thereby facilitating jam removal. It becomes possible to do so.

[0010] According to the third aspect of the present invention, by rotating the large paper feed device around the fulcrum on the back side, the paper feed path can be widened toward the front side, and jam removal can be easily performed. By rotating the large paper feeder around the fulcrum on the front side, it is possible to replenish paper to the large paper feeder or replace paper of different sizes from the front side of the image forming apparatus main body. This can be done easily.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the invention according to claim 1 will be explained based on FIG. Reference numeral 1 denotes a main body of an image forming apparatus. A document reading device 2 for optically reading the contents of a document is attached to the upper part of the main body 1, and a paper conveyance path 3 and an image forming section 4 are provided inside. . The image forming section 4 includes a rotatably held photoreceptor 5, a charger 6 that applies a voltage to the photoreceptor 5 to charge it, and a static image formed on the photoreceptor 5 by the document reading device 2. A developing device 7 that develops an electrostatic latent image, a transfer charger 8 that transfers the developed image on the photoreceptor 5 to paper, a separation charger 9 that separates the paper from the photoreceptor 5, and a cleaning unit 10 that cleans the photoreceptor 5. and a fixing section 11 that holds the paper that has passed through the transfer charger 8 and fixes the transferred image on the paper. Furthermore, the paper conveyance path 3 includes a conveyance roller 12.
, a reverse roller 13 , and a registration roller 14 are arranged in this order, and a paper ejection roller 16 is provided between the fixing section 11 and the paper ejection receiver 15 .

The main body 1 includes a plurality of paper feed cassettes 17.
are arranged at intervals in the vertical direction, and a paper feed roller 18 and a separation roller 19 are arranged at the tip of these paper feed cassettes 17.
are rotatably provided in contact with each other. Further, a paper guide 20 along the front end surface of these paper feed cassettes 17 is fixedly provided on the main body 1. and,
A large paper feeding device 21 is attached to the right side of the main body 1. This large paper feeding device includes a lifting table 23 that is raised and lowered by a belt 22, a sheet feeding roller 25 that comes into contact with sheets 24 stacked on the lifting table 23, and a regulating plate 26 that aligns the leading edges of the sheets 24. have. A paper feeding path 28 is formed by arranging the side surface 27 of the large paper feeding device 21 and the paper guide 20 facing each other with a predetermined distance therebetween. Further, two transport rollers 29 connected to a motor (not shown) are rotatably held in the paper guide 20, and a transport roller 30 in contact with these transport rollers 29 is rotatably connected to the large paper feeder 21. is maintained.

Furthermore, a desk 31 on which the main body 1 is placed
Also, a plurality of paper feed cassettes 17 are arranged in the vertical direction. A paper feed roller 18 and a separation roller 19 are provided at the leading end of these paper feed cassettes 17, and a paper feed path 32 is provided for supplying the paper in the paper feed cassette 17 to the paper feed path 28. ing.

[0014] In such a configuration, when feeding paper,
Paper feed cassette 17 selected from main body 1 or desk 31
The paper is conveyed to the registration rollers 14 by the paper feed path 28 or by the paper feed path 32 and the paper feed path 28. Here, the side surface 27 of the large paper feeder 21 is connected to the paper feed path 2.
8 can also be used as a paper guide facing the paper guide 20, making it possible to reduce the number of paper guides and simplify the support structure that supports the paper guides. Furthermore, since the side surface 27 of the large paper feeder 21 has higher rigidity than a single paper guide, the support strength of the transport roller 30 can be increased to maintain the contact pressure between the pair of transport rollers 29 and 30 above a certain level. This makes it possible to reduce the occurrence of paper misfeeds, paper jams, etc. Note that when transferring images onto multiple sheets of paper at once, the paper 24 from the large paper feeder 21 is fed to the registration rollers 14 by the paper feed roller 25.

Next, an embodiment of the invention of claim 2 is shown in FIG.
This will be explained based on FIGS. Components that are the same as those in the above embodiments are designated by the same reference numerals, and description thereof will be omitted (the same applies hereinafter). As shown in FIG. 2, the large paper feeder 21 has a pair of side fences 33 that guide both side edges of the paper when viewed from above. Near one side of the back side of the paper guide 20,
A fulcrum portion 34 is provided which holds the entire large sheet feeding device 21 rotatably about a vertical rotation axis. Furthermore, one end of a plurality of leaf springs 35 is fixed to the regulation plate 26 of the large paper feeder 21, and as shown in FIG.
A conveying roller 30 is rotatably held by bent pieces 36 formed on both sides of the conveyor roller 30 .

In such a configuration, if a jam occurs in the paper feed path 28, as shown in FIG.
As shown by the imaginary line in FIG. 3, by rotating the entire large sheet feeding device 21 counterclockwise about the fulcrum 34, the sheet feeding path 28 can be opened widely toward the front side. This makes it possible to easily handle jams.

Furthermore, an embodiment of the invention of claim 3 is shown in FIG.
The explanation will be based on. In this embodiment, a fulcrum part 34 is provided on one side of the back side of the paper guide 20 to hold the entire large paper feeding device 21 rotatably around a vertical rotation axis, and a fulcrum part 34 is provided on one side of the front side of the paper guide 20. A fulcrum part 37 is provided near the side to hold the upper part of the large paper feeder 21 rotatably about a vertical rotation axis.

In such a configuration, if a jam occurs in the paper feed path 28, the entire large paper feed device 21 is rotated counterclockwise around the fulcrum portion 34 on the back side, as explained in the above embodiment. By rotating the paper feed path 2
Open 8. In addition, when replenishing paper 24 to the large paper feeder 21 or replacing paper 24 of different sizes, the large paper feeder 21 is
Rotate the top of the clockwise. As a result, the paper 24 is placed on the lifting platform 23 of the large paper feeder 21 from the front side of the main body 1.
can be easily inserted.

[0019]

[Effects of the Invention] The invention according to claim 1 provides an image forming section, a paper feed cassette disposed below the image forming section, and a paper feed cassette arranged vertically from the tip of the paper feed cassette toward the image forming section. An extending paper guide, a large paper feeder whose side surfaces are arranged opposite to each other with a predetermined gap between the paper guide, and a paper feeder formed between the paper guide and the side surface of the large paper feeder. Since the large paper feeding device is configured with a passage, the side surface of the large paper feeding device can also be used as one of the paper guides of a pair for forming the paper feeding passage.
The number of paper guides can be reduced and the support structure for supporting the paper guides can be simplified, and the sides of the large paper feeder are more rigid than a single paper guide.
It is possible to increase the support strength of the conveyance rollers and maintain the contact pressure between the pair of conveyance rollers above a certain level, which has the effect of reducing the occurrence of paper non-feeding, paper jams, etc.

The invention of claim 2 is based on claim 1, since a fulcrum portion for rotatably holding the large paper feed device with a vertical rotation axis is provided near one side of the back side of the paper guide. By rotating the large paper feed device around the fulcrum, the paper feed path can be widened toward the front.
This has the effect that jam processing can be easily performed.

[0021] The invention according to claim 3 is the invention according to claim 1, in which a large paper feeding device is rotatably held with a vertical rotation axis in the vicinity of one side of the back side and one side of the front side of the paper guide. By rotating the large paper feeding device around the fulcrum on the back side, the paper feeding path can be widened toward the front, making it easier to clear jams. Also,
By rotating the large paper feed device around the fulcrum on the front side, it is possible to easily replenish paper to the large paper feed device or replace paper of different sizes from the front side of the image forming apparatus main body. It has the effect of being able to.

[Brief explanation of drawings]

FIG. 1 is a front view showing the inside of an image forming apparatus according to a first aspect of the invention.

FIG. 2 is a plan view, partially in cross section, showing the rotational movement of the large paper feeding device, according to the second aspect of the invention;

FIG. 3 is a plan view of the copying machine.

FIG. 4 is a partial longitudinal side view showing the support structure of the conveyance roller.

FIG. 5 is a plan view, partially in cross section, showing the rotational movement of the large paper feeding device, according to the third aspect of the present invention;

[Explanation of symbols]

4 Image forming section 17 Paper cassette 20 Paper guide 21 Large paper feeder 27　　　　　Side view of large paper feeder 28 Paper feed path

Claims (3)

[Claims] 1. An image forming section, a paper feed cassette disposed below the image forming section, and a paper guide extending vertically from the tip of the paper feed cassette toward the image forming section. The paper feeder includes a large paper feeder whose side surfaces are arranged opposite to each other with a predetermined gap in the paper guide, and a paper feed path formed between the paper guide and the side surface of the large paper feeder. A paper feed guide device for an image forming apparatus. 2. The image according to claim 1, characterized in that a fulcrum portion for rotatably holding the large paper feed device with a vertical rotation axis is provided near one side of the rear side of the paper guide. Paper feed guide device of forming device. [Claim 3] A fulcrum part is provided near one side on the back side and one side on the front side of the paper guide for rotatably holding the large paper feeding device with a vertical rotation axis. A paper feed guide device for an image forming apparatus according to claim 1.