JPH0789675A - Image forming device - Google Patents

Abstract

PURPOSE:To secure both of the medium feeding function and the double-face copying function, as for an image forming device which secures a medium feeding means accommodation part which feeds the medium such as recording paper in the device body. CONSTITUTION:In a medium feeding means accommodation part 20 which is formed in a device body 3, a paper sheet feeding mechanism 26 which is equipped with a paper feeding cassette 25 and feeds a paper sheet P to an image forming means 10 is installed in consideration of the size of the paper feeding cassette 25 and the feeding direction of the paper sheet P, and an ADD 27 is installed at the rest part. The image forming device is equipped with the wide utilization performance by securing both the paper feeding function for the paper sheet P and the double-face copying function.

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 an electronic copying machine or a laser printer, and more particularly to an image forming apparatus having a double-sided copying function.

[0002]

2. Description of the Related Art In recent years, with the diversification of image forming sizes,
A device with an increased number of paper feed cassettes is required. And, as one that can realize this, one paper cassette
An image forming apparatus having a plurality of stages is put on a multi-cassette feeder having four stages of sheet feeding cassettes, and a sheet feeding cassette having a total of five stages can be fed.

Further, in an image forming apparatus normally mounted on a multi-cassette feeder of this type, a front loading cassette type in which a paper feeding cassette can be pulled out to the front side is adopted in order to save space. is doing.

Conventionally, in the image forming apparatus of the front loading cassette type, since it is necessary to incorporate the paper feeding cassette into the main body of the apparatus, a conventional S-shaped sheet carrying-in path having two U-turn portions is provided. There is no space for incorporating a feeding means (hereinafter referred to as ADD) for double-sided image formation, which has a large height dimension and is guided to the stacker through the stacker, and does not have a double-sided copying function.

[0005]

As described above, in the image forming apparatus in which the medium feeding means accommodating portion is secured in the apparatus main body such as the conventional front loading cassette type image forming apparatus, the apparatus is Both the feeding means from the paper feed cassette and the ADD are not incorporated in the main body.

However, in the recent environment, it is required to install the ADD (optional) even for a device having a class of 30 or less. On the other hand, there is a problem that it is not desirable to reduce the number of paper feed cassettes due to diversification of image forming size.

The present invention has been made to solve the above-mentioned problems, and in an image forming apparatus having a medium feeding means accommodating portion for feeding a medium such as recording paper in the main body of the apparatus, the medium feeding A feeding means having a cassette in the means accommodating section and A
An object of the present invention is to provide an image forming apparatus having both a DD function and a versatile function that can secure both a medium feeding function and a double-sided copying function.

[0008]

As a first means for solving the above-mentioned problems, the present invention is an image forming apparatus in which a medium feeding means accommodating portion is secured in an apparatus main body. An image forming unit that is built in the main body and forms an image on a recording medium, and a medium storage that stores a recording medium that is provided in the medium feeding unit storage unit of the apparatus main body and that is image-formed by the image forming unit. A first medium feeding means having a cassette for feeding a recording medium to the image forming means in a first direction, and a first medium feeding means provided in the medium feeding means accommodating portion. The recording medium storage unit is disposed so as to face the vicinity of the disposition position, and the recording medium on which the image is formed on one side by the image forming unit is transferred to the recording medium storage unit from a second direction opposite to the first direction. Receiving images on the other side of the recording medium A second medium feeding unit for double-sided image formation, which is taken out from the recording medium storage unit to be formed, is guided from the second direction, is guided to the first direction, and is fed to be supplied toward the image forming unit. It is configured to include.

As a second means, there is provided an image forming apparatus in which a medium feeding means accommodating portion is secured in the main body of the apparatus, which is built in the main body of the apparatus and forms an image on a recording medium. And a medium accommodating cassette for accommodating a recording medium which is provided in the medium feeding means accommodating portion of the apparatus main body and in which an image is formed by the image forming means, and a recording medium is supplied to the image forming means. The first medium feeding means for feeding in the direction 1 and the recording medium housing portion are provided in the medium feeding means housing portion so as to face each other in the vicinity of the arrangement position of the first medium feeding means. The recording medium having the image formed on one surface side by the image forming means is received in the recording medium housing portion from a second direction opposite to the first direction, and the recording is performed to form an image on the other surface of the recording medium. From the medium storage unit to the second A second medium feeding unit for double-sided image formation, which is taken out from the opposite direction and guided in the first direction to feed toward the image forming unit; and the first and second medium feeding units. It is configured such that it is provided with withdrawing means that holds the medium feeding means accommodating portion of the apparatus main body and can be inserted into and removed from the front side.

As a third means, there is provided an image forming apparatus in which a medium feeding means accommodating portion is secured in the main body of the apparatus, which is built in the main body of the apparatus and forms an image on a recording medium. And a medium storage cassette that stores a recording medium that is formed in the medium feeding means storage portion of the apparatus main body and that is image-formed by the image forming means, and supplies the recording medium to the image forming means. The first medium feeding means for feeding, and the recording medium housing portion arranged in the medium feeding means housing portion so as to face the vicinity of the disposition position of the first medium feeding means, and by the image forming means. Double-sided for receiving a recording medium having an image formed on one side thereof in the recording medium housing section and for feeding from the recording medium housing section toward the image forming means to form an image on the other surface of the recording medium. For image formation A second medium feeding unit for double-sided image formation, wherein the second medium feeding unit for double-sided image formation carries in a recording medium having an image formed on the one side thereof from one end side of the recording medium storage unit. Mechanism, a carry-out mechanism for taking out the recording medium carried in by the carrying-in mechanism and stored in the recording medium storage portion to the one end side, and a U-turn transport of the recording medium taken out from the one end side of the recording medium storage portion by the carry-out mechanism Then, a transport mechanism for transporting to the other end of the recording medium accommodating portion so as to join and transport in the feeding direction of the first medium feeding means is provided.

As a fourth means, there is provided an image forming apparatus in which a medium feeding means accommodating portion is secured in the main body of the apparatus, which is built in the main body of the apparatus and forms an image on a recording medium. And a medium storage cassette that stores a recording medium that is formed in the medium feeding means storage portion of the apparatus main body and that is image-formed by the image forming means, and supplies the recording medium to the image forming means. The first medium feeding means for feeding, and the recording medium housing portion arranged in the medium feeding means housing portion so as to face the vicinity of the disposition position of the first medium feeding means, and by the image forming means. Double-sided for receiving a recording medium having an image formed on one side thereof in the recording medium housing section and for feeding from the recording medium housing section toward the image forming means to form an image on the other surface of the recording medium. For image formation A second medium feeding unit for double-sided image formation, wherein the second medium feeding unit for double-sided image formation carries in a recording medium having an image formed on the one side thereof from one end side of the recording medium storage unit. Mechanism, a carry-out mechanism for taking out the recording medium carried in by the carrying-in mechanism and stored in the recording medium storage portion to the one end side, and a U-turn transport of the recording medium taken out from the one end side of the recording medium storage portion by the carry-out mechanism And a conveyance mechanism for conveying the recording medium in the feeding direction of the first medium feeding unit by feeding the recording medium to the other end side of the recording medium storage unit. It is configured such that a part of the guide is also used for switching.

[0012]

In other words, according to the first means, the medium storage cassette is formed by considering the size of the medium storage cassette and the feeding direction of the recording medium in the medium feeding means storage portion formed in the main body of the apparatus. Since the first medium feeding unit for feeding the recording medium to the image forming unit is provided, and the second medium feeding unit for double-sided image formation is provided in the remaining portion, It is possible to provide a highly versatile image forming apparatus capable of ensuring both the medium feeding function and the double-sided copying function.

According to the second means, in addition to the function of the first means, further, the first and second medium feeding means are held, and the medium feeding means accommodating portion of the apparatus main body is held. Since it has a withdrawal means that can be freely inserted and removed from the front side,
Space saving is possible without the need for a drawer space on the side surface, and moreover, replenishment of recording media to the cassette,
Jam processing and the like become easy, and operability can be improved.

According to the third means, the first medium feeding means for feeding the recording medium from the medium storing cassette and the second medium feeding means for double-sided image formation are limited to some extent. It is also possible to configure it in the medium feeding means accommodating portion of the apparatus main body.

Further, according to the fourth means, since a part of the carrying-in mechanism of the second medium feeding means for double-sided image formation and the recording medium carrying guide of the carrying mechanism are combined and switched and used. It is possible to simplify the configuration.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is an external view of a unit apparatus in which an electrophotographic copying apparatus 1 as an image forming apparatus of the present invention is placed on a multi-cassette feeder 2 which is a sheet feeding apparatus. FIG. 2 shows the inside of the image forming apparatus 1. The structure is shown schematically.

On the upper surface side of the apparatus main body 3 of the electrophotographic copying apparatus 1, a document glass 4 as a document placing table is arranged, and an operation panel 5 is arranged along the front edge portion. Further, the document holding cover 6 is provided on the rear edge of the upper surface.
Is rotatably attached so as to press the document D placed on the document glass 4.

On the right side surface of the apparatus main body 3, a manual feed guide 7 is provided.
Is provided. A paper discharge tray 8 is attached to the left side surface of the apparatus body 3. Further, as shown in FIG. 2, the image forming means 10 is accommodated in the electrophotographic copying apparatus 1. The image forming means 10 has the following configuration.

That is, a photosensitive drum 11 as an image bearing member is rotatably provided in a substantially central portion of the apparatus main body 3. Around the photosensitive drum 11, along the rotation direction (arrow direction), the charging device 12, the LED erasing array 13, the developing device 14, the transfer device 15, the peeling device 16,
A cleaning device 17 and a charge eliminating device 18 are sequentially arranged.

Further, in the upper part of the apparatus main body 3, the LE
Between the D erasing array 13 and the developing device 14, an optical system movable exposure device 19 for exposing the image information of the document D set on the document glass 4 is provided.

The image forming means 10 first comprises the charging device 12.
By the operation of, the surface potential of the photosensitive drum 11 is uniformly charged,
Thereafter, the exposure device 19 scans and exposes the original image of the original D on the surface of the photosensitive drum 11. As a result, the surface potential of the portion of the photosensitive drum 11 exposed to light is attenuated, and an electrostatic latent image is formed.

Next, the electrostatic latent image is developed by being opposed to the developing device 14, and a toner image is formed. After that, the toner image on the photoconductor drum 11 is electrostatically transferred to the paper P sent to the image transfer unit 30 by the transfer device 15.

The paper P having the toner image transferred thereto is sent to a fixing device 33 provided in the direction of the paper discharge tray 8 and subjected to a toner image fixing process. Further, the lower part inside the apparatus main body 3 is a medium feeding means accommodating portion 20 for accommodating means for feeding the paper P which is a recording medium. In this embodiment, the size of the medium feeding means accommodating portion 20 is equal to the accommodating space of the 500-sheet cassette.

Then, in the medium feeding means accommodating portion 20, as will be described later, a first medium feeding means is provided with a paper feeding cassette 25 which is a medium accommodating cassette capable of accommodating the paper P of A4R size or smaller. A sheet feeding mechanism 26 as means is provided, and a sheet feeding mechanism (hereinafter referred to as ADD) 27 as second medium feeding means for double-sided image formation is incorporated in the remaining space.

Further, in the apparatus main body 3, the paper feeding mechanism 2 is provided.
6 or a sheet P automatically fed from the multi-cassette feeder 2, a sheet P having its front and back reversed by the ADD 27, or a sheet P manually fed from the manual feed guide 7.
A sheet conveying path 31 is formed to guide the sheet to the sheet discharge tray 8 via the image transfer section 30 between the transfer device 15 and the photosensitive drum 11.

A pair of registration rollers 32 as an aligning unit are located upstream of the image transfer unit 30 in the sheet conveying path 31, and a fixing device 33 is located downstream of the image transfer unit 30. , And the discharge roller pair 34 are arranged.

Further, between the fixing device 33 and the paper discharge roller pair 34, a gate 35 is provided as a distributing means for sending the fixed paper P to the ADD 27 as required. Further, it is located on the upstream side of the position where the registration roller pair 32 is arranged on the paper transport path 31, and is located at a midway portion of the paper feed transport path 31a for transporting the paper P fed from the paper feed cassette 25 or the multi-cassette feeder 2. Is provided with a second pair of registration rollers 36.

The multi-cassette feeder 2 has four-stage paper feed cassettes 40a, 40b, 40c, 40d (see FIG. 1).
And these paper feed cassettes 40a, 40b, 40c,
The sheet P is selectively taken out from 40d and sent to a communication path 42 provided on the lower right side in the apparatus main body 3 via a sheet conveying path 41 (see FIG. 2) provided on the upper surface side.

Since the construction of the multi-cassette feeder 2 itself is not directly related to the present invention, its detailed description is omitted. Next, with reference to FIG. 2 and FIG. 3, the sheet feeding mechanism 26 as the first medium feeding means arranged in the medium feeding means accommodating portion 20 will be described.

In this embodiment, the sheet feeding mechanism 26 can store 250 sheets of A4R size or smaller sheet P on the right side of the medium feeding means storing section 20 having the same size as the storage space of the 500 sheet cassette. The paper feeding cassette 25 is arranged.

Further, on the right end side of the paper feed cassette 25, there is provided a mechanism 44 for feeding the paper P in a first direction (right direction) near the paper feed transport path 31a. That is, the pickup roller 4 that takes out the paper P in the paper feed cassette 25
5, a feeding roller 46 that carries out the paper P taken out by the pickup roller 45, a separating member 47 that separates the paper P that is to be taken out together with the paper P fed by the feeding roller 46, and the like Has been arranged.

Next, a paper feeding mechanism (ADD) 27 as a second medium feeding means for double-sided image formation, which is arranged in the remaining space of the paper feeding mechanism 26 thus constructed.
Will be described with reference to FIGS. 2 to 6.

As shown in FIGS. 2 and 3, the ADD 27 has a stacker 50 below the paper feed cassette 25 as a recording medium storage unit capable of storing 20 to 50 sheets of A3 size paper P.

The left end side of the stacker 50, that is,
At a position below the fixing device 33, the carry-in mechanism 55 that carries in the sheet P, which has passed through the fixing device 33 and is guided through the gate 35 and on which one side of the image is formed, from one end side (left end side) of the stacker 50. Is provided.

A carry-out mechanism 56 for taking out the sheets P carried in by the carry-in mechanism 55 and stored in the stacker 50 to the one end side (left end side), and the stacker 5 by the carry-out mechanism 56.
The paper P taken out from one end side of 0 is conveyed in a U-turn, and is fed to the other end side (right end side) through the upper surface side of the stacker 50, thereby feeding in the same feeding direction as the paper feeding mechanism 26. A transport mechanism 57 that merges and transports the paper to the paper transport path 31a is provided.

As shown in FIGS. 4 and 5, the carry-in mechanism 55 comprises a fixed guide plate pair 60, a conveyance roller pair 61, a movable guide plate pair 62 as a recording medium conveyance guide, and a conveyance roller pair 65.

The carry-out mechanism 56 comprises a pickup roller 66. In addition, the transport mechanism 57 includes the feeding roller 7
0 and the separating member 71, the conveying roller pair 72, the arc-shaped fixed guide plate pair 73 for U-turn, the movable guide plate pair 62 as the recording medium conveying guide, the fixed guide plate pair 74, the conveying roller pair 75, the fixed guide. It is composed of a plate pair 76 and a conveyance roller pair 77.

The movable guide plate pair 62 also serves as a recording medium transport guide for the carry-in mechanism 55 and the transport mechanism 57, and has a structure as shown in FIG. That is, the movable guide plate pair 62 is swingably supported with the shaft 80 as a fulcrum, and one end side of the movable guide plate pair 62 is always urged upward on the rear side thereof so that the movable guide plate pair 62 is inclined. A tension spring 81 is provided, and
The tension spring 8 is arranged so that the movable guide plate pair 62 becomes horizontal.
The solenoid 82 is configured to swing and displace against the biasing force of 1. When the paper P is carried into the stacker 50 by the carry-in mechanism 55, the solenoid 82 is used.
Is turned off to bring it into an inclined state, and when the sheet P is conveyed by the conveying mechanism 57 to the side of the paper feed conveying path 31a and sent, the solenoid 82 is turned on to bring it into a horizontal state.

Next, a double-sided copy operation using the ADD 27 will be described with reference to FIGS. 2, 4 and 5. The sheet P having the toner image transferred to one surface thereof by passing through the image transfer unit 30 of the image forming unit 10 passes through the fixing device 33, so that the toner image is fixed. At this time, the gate 35 provided in advance on the exit side of the fixing device 33 is shown in FIG.
Has been switched to the solid line state of FIG.
It is guided to the ADD 27 side without being discharged to.

On the other hand, in the ADD 27, the movable guide plate pair 6
2 is switched to the inclined state (the state indicated by the chain double-dashed line in FIGS. 4 and 5), and the pair of conveying rollers 61 of the carry-in mechanism 55,
And the pair of transport rollers 65 are rotating in the directions of the arrows, respectively, and the paper P is fed in the direction of the solid arrows and the stacker 50
Accumulated in.

When a predetermined number of sheets P are stacked on the stacker 50 in this way, the pickup roller 66 of the carry-out mechanism 56 processes and rolls the upper surface of the sheet P, and the rotation in the direction of the arrow in FIG. Take out the paper P to the left of the stacker 50.

At this time, the feed roller 70 and the feed roller pair 72 of the feed mechanism 57 are rotating in the arrow direction, and the movable guide plate pair 62 is switched to the horizontal state (solid line state in FIG. 5). .

Then, the sheet P is U-turned as shown by the broken line arrow in FIG. 5, and then conveyed to the right. And
The paper is fed into the paper feed transport path 31a through a pair of fixed guide plates 74 and 76 provided on the upper surface side of the paper feed cassette 25. After that, a U-turn is made to the left to reverse the front and back sides, and the sheets are fed again to the image transfer section 30 for double-sided copying.

As described above, the ADD 27 of the present invention
Since the paper P to be double-sided copied is carried in from the left end side of the stacker 50 via a short, generally U-shaped carry-in path, the width S having two U-turn portions and a large height S is different from the conventional case.
The height of ADD itself can be kept low compared to the case where the stacker is carried in from the right side of the stacker via the carry-in path, which makes the medium feeding means of the same size as the accommodation space of the 500-sheet cassette. It can be arranged in the remaining space in which the sheet feeding mechanism 26 of the storage section 20 is arranged.

By considering the size of the paper feed cassette 25 and the feeding direction of the paper P in the medium feeding means accommodating section 20 formed in the apparatus main body 3, the image forming means 10 is provided with the paper feed cassette 25. Since the paper feeding mechanism 26 for feeding the paper P is provided in the above and the ADD 27 is provided in the remaining portion, both the paper feeding function of the paper P and the double-sided copying function can be ensured. It has wide availability.

Further, the paper feeding mechanism 26 and the ADD 27
Most of the above are incorporated in a pull-out type support body 100 (see FIG. 1) as a pull-out means that can be inserted into and removed from the medium feeding means accommodating portion 20 of the apparatus main body 2 from the front side. The member in the area E surrounded by the chain double-dashed line in FIG. 3 can be pulled out to the front side together with the pull-out support 100.

For this reason, it is possible to save space without requiring a drawer space or the like on the side surface of the apparatus main body 3, and moreover, it becomes easy to replenish the paper P in the paper feed cassette 25, jam processing, etc., and to improve operability. Can be improved.

Further, the paper P of the ADD 27 is stacked in the stacker 50.
The sheet conveyance guide of the carry-in mechanism 55 and the sheet conveyance guide of the conveyance mechanism 57 taken out from the stacker 50 are commonly used by the movable guide plate pair 62 which can be swung, and the angle is switched and used. Therefore, the configuration can be simplified. It should be noted that the present invention is not limited to the above-described embodiment, and it goes without saying that various modifications can be made without departing from the spirit of the present invention.

[0049]

As described above, the present invention has the following effects. According to the image forming apparatus of claim 1, the medium storage cassette is provided by considering the size of the medium storage cassette and the feeding direction of the recording medium in the medium feeding means storage portion formed in the apparatus main body. Since the first medium feeding unit for feeding the recording medium to the image forming unit is provided, and the second medium feeding unit for double-sided image formation is provided in the remaining portion, the medium is formed. It is possible to have wide availability by ensuring both the paper feeding function and the double-sided copying function.

Further, according to the image forming apparatus of the second aspect, in addition to the above, the first and second medium feeding means are held, and the medium feeding means accommodating portion of the apparatus main body is provided from the front side. Since it has a pull-out means that can be inserted and removed freely, space can be saved without the need for a pull-out space on the side surface, and moreover, it is easy to replenish the cassette with recording media and to eliminate jams, improving operability. Can be achieved.

Further, according to the image forming apparatus of the third aspect, the first medium feeding means for feeding the recording medium from the medium storing cassette and the second medium feeding means for double-sided image formation are provided. It is possible to configure the medium feeding means housing portion of the apparatus body to a limited extent.

Further, according to the image forming apparatus of the fourth aspect, a part of the carrying-in mechanism of the second medium feeding means for double-sided image forming and the recording medium carrying guide of the carrying mechanism are also used and switched. Therefore, the configuration can be simplified.

[Brief description of drawings]

FIG. 1 is an external view of a unit apparatus mounted on a multi-cassette feeder as an embodiment of an electrophotographic copying apparatus as an image forming apparatus of the present invention.

FIG. 2 is a front sectional view schematically showing the internal structure of the image forming apparatus shown in FIG.

FIG. 3 is a schematic view showing a sheet feeding mechanism and ADD which are the main parts of the image forming apparatus shown in FIG.

FIG. 4 is a schematic configuration diagram of ADD.

FIG. 5 is an explanatory diagram showing the flow of paper in ADD.

FIG. 6 is a perspective view showing a configuration of a movable guide plate pair of ADD.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Electrophotographic copying device (image forming device), 2 ... Multi-cassette feeder (paper feeding device), 3 ... Device body, 10 ... Image forming means, 11 ... Photosensitive drum (image carrier), 20 ...
Medium feeding means accommodating section, 25 ... Paper feeding cassette (medium accommodating cassette), 26 ... Paper feeding mechanism (first medium feeding means), 27 ... ADD (second medium feeding means), 30 ... Image Transfer unit, 31 ... Paper transport path, 31a ... Paper transport path, 3
3 ... Fixing device, 35 ... Gate (sorting means), 40a, 4
0b, 40c, 40 ... Paper feeding cassette, 45 ... Pickup roller, 46 ... Feeding roller, 50 ... Stacker, 55 ...
Carry-in mechanism, 56 ... carry-out mechanism, 57 ... transport mechanism, 60 ... fixed guide plate pair, 61 ... transport roller pair, 62 ... movable guide plate pair (recording medium transport guide), 65 ... transport roller pair, 6
6 ... Pickup roller, 70 ... Feed roller, 72, 7
5, 77 ... Conveying roller pair, 73, 74, 76 ... Fixed guide plate pair, 80 ... Shaft, 81 ... Tension spring, 82 ... Solenoid, 100 ... Draw-out type support (drawing means).

Claims (4)

[Claims] 1. An image forming apparatus in which a medium feeding means accommodating portion is secured in an apparatus body, the image forming means being incorporated in the apparatus body and forming an image on a recording medium, the apparatus body. A medium storage cassette which is provided in the medium feeding means storage section and stores a recording medium on which an image is formed by the image forming means, and is fed in a first direction to supply the recording medium to the image forming means. A first medium feeding means, and a recording medium accommodating portion which is provided in the medium feeding means accommodating portion and faces the vicinity of the disposition position of the first medium feeding means, and which is covered by the image forming means. The recording medium having the image formed on the side thereof is received from the recording medium storage section from the second direction opposite to the first direction and the image is formed on the other surface of the recording medium from the recording medium storage section. Take out from the direction of 2 and An image forming apparatus comprising a second medium feeding means for double-sided image formation for feeding to supply toward the image forming unit guided in a direction, to become comprises a a. 2. An image forming apparatus in which a medium feeding means accommodating portion is secured in the apparatus body, the image forming means being incorporated in the apparatus body and forming an image on a recording medium, the apparatus body. A medium storage cassette which is provided in the medium feeding means storage section and stores a recording medium on which an image is formed by the image forming means, and is fed in a first direction to supply the recording medium to the image forming means. A first medium feeding means, and a recording medium accommodating portion which is provided in the medium feeding means accommodating portion and faces the vicinity of the disposition position of the first medium feeding means, and which is covered by the image forming means. The recording medium having the image formed on the side thereof is received from the recording medium storage section from the second direction opposite to the first direction and the image is formed on the other surface of the recording medium from the recording medium storage section. Take out from the direction of 2 and The second medium feeding means for double-sided image formation, which guides the sheet to the image forming means and feeds it toward the image forming means, and holds the first and second medium feeding means, An image forming apparatus comprising: a pulling-out unit that can be inserted into and removed from the medium feeding unit housing section from the front side. 3. An image forming apparatus in which a medium feeding means accommodating portion is secured in an apparatus body, the image forming means being incorporated in the apparatus body and forming an image on a recording medium, the apparatus body. A first medium for supplying a recording medium to the image forming means, the medium containing cassette for containing a recording medium on which an image is formed by the image forming means The recording medium accommodating portion is disposed inside the medium feeding means accommodating portion so as to face the vicinity of the arrangement position of the first medium feeding means, and the image forming means forms an image on one surface side. Second side for double-sided image formation, in which the formed recording medium is received in the recording medium storage unit and is fed so as to be supplied from the recording medium storage unit toward the image forming means to form an image on the other surface of the recording medium. Medium feeding means of A second medium feeding unit for double-sided image formation, wherein the second medium feeding unit carries in the recording medium having the image formed on the one side from one end side of the recording medium housing section; And a carrying-out mechanism for taking out the recording medium housed in the recording medium housing part to the one end side, and carrying out the U-turn of the recording medium taken out from the one end side of the recording medium housing part by the carrying-out mechanism, An image forming apparatus, comprising: a transport mechanism that transports the sheet to the end side to join the first medium feeding unit in the feeding direction. 4. An image forming apparatus in which a medium feeding means accommodating portion is secured in the apparatus body, the image forming apparatus being incorporated in the apparatus body and forming an image on a recording medium, the apparatus body. A first medium for supplying a recording medium to the image forming means, the medium containing cassette for containing a recording medium on which an image is formed by the image forming means The recording medium accommodating portion is disposed inside the medium feeding means accommodating portion so as to face the vicinity of the arrangement position of the first medium feeding means, and the image forming means forms an image on one surface side. Second side for double-sided image formation in which the formed recording medium is received in the recording medium storage section and is fed so as to be supplied from the recording medium storage section toward the image forming means to form an image on the other surface of the recording medium. Medium feeding means of A second medium feeding unit for double-sided image formation, wherein the second medium feeding unit carries in the recording medium having the image formed on the one side from one end side of the recording medium housing section; And a carrying-out mechanism for taking out the recording medium housed in the recording medium housing part to the one end side, and carrying out the U-turn of the recording medium taken out from the one end side of the recording medium housing part by the carrying-out mechanism, And a transport mechanism for merging and transporting in the feeding direction of the first medium feeding means by feeding to the end side, and also serving as a part of the recording medium transport guide of the carry-in mechanism and the transport mechanism. An image forming apparatus having a configuration of switching and using.