JP2851905B2 - Image forming device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Application Field] The present invention discharges a sheet with a copy image side facing down.
The present invention relates to an image forming apparatus having a backside discharge mode.

[Conventional technology]

Conventionally, in a copier capable of page-sequential copying (ADF inserts a document in page order), the discharged sheets are stacked in page order.
The paper (transfer paper) after image formation is inverted during transportation and stacked with the copy surface facing downward.

Note that this mode is generally called a backside discharge mode.

FIG. 7 shows an operation timing chart in the conventional backside discharge mode.

In this figure, the contents of each member described below are all described later.

After the transfer paper has passed through the fixing device, it is detected by the fixing detection sensor, and after 0.8 seconds, the leading end of the transfer paper is detected by the sensor A. At the point when the leading edge of the transfer paper reaches below the pressure drive roller 0.5 seconds after the leading edge detection, the pressure solenoid (SO
L) is turned on and pressurized. At that time, the pressure driving roller is rotating in the counterclockwise direction, and draws the transfer paper toward the intermediate tray. When the rear end of the transfer paper is detected by the sensor A,
Reverse the rotation direction of the pressure drive roller clockwise,
The transfer paper is sent out toward the discharge roller. The paper discharge sensor detects that the leading edge of the transfer paper is gripped by the paper discharge roller, turns off the pressure solenoid of the pressure drive roller 0.25 seconds after the detection, and releases the pressure. The rotation direction of the pressure drive roller is switched in the counterclockwise direction to prepare for the next transfer sheet insertion. The same operation is repeated each time the transfer paper is fed.

This example is for the repeat of A4 landscape size transfer paper.
Since it takes time to insert and discharge the transfer paper in the transfer paper reversing unit, the paper feed repeat interval of the transfer paper is 3 seconds, and the transfer paper interval at that time is 540 mm.

[Problems to be solved by the invention]

In the related art, in order to invert a sheet in a narrow reversing path, a sufficient sheet interval (for example, twice or more the length of a transfer sheet) for inserting and discharging the sheet in the reversing path must be provided.
At the time of reversal discharge, there is a disadvantage that the productivity of copying is reduced.

In the future, page order copy will be inevitable, including facsimile,
Higher speed is required in the backside discharge mode.

An object of the present invention is a form of a general image forming apparatus that discharges an image forming surface upward, and in order to cope with image forming in a page order which will become a mainstream in digital machines and the like in the future, a page order process is performed. An object of the present invention is to provide an image forming apparatus that speeds up the output of continuous image formation in backside discharge in which an image forming surface is discharged upward.

[Means for solving the problem]

An object of the present invention is to provide an image forming apparatus including a reversing device for reversing and feeding a sheet discharged from a fixing unit to a discharge unit after a toner image is fixed on an upper surface, wherein the reversing device includes the entire sheet discharged from the fixing unit. Means for temporarily holding paper and a pressurizing drive roller for sending out paper in the holding position toward the discharge unit and having a rotation speed higher than a linear speed in an image forming process Is achieved by

In the first means, the first driving means may press the paper by the pressure driving roller so as to hold the second paper at the holding position while the first paper is being sent from the holding position to the discharge unit. , Pressure release, and normal rotation and reversal.

[Action]

According to the first means, the sheet is fed to a holding position for holding the entire sheet discharged from the fixing unit, and the pressure driving roller discharges the sheet from the holding position at a linear speed higher than the linear speed of the image forming process operation. Send out to the department.

Further, according to the second means, while the pressure driving roller is sending the first sheet from the holding position to the discharge section, the pressing drive roller moves to the second position at the holding position.
Drive control is performed to hold the paper.

〔Example〕

 Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a block diagram showing a copying machine main body according to an embodiment of the present invention, and FIG. 2 is a block diagram showing an entire copying machine. A substantially central portion of the copying machine body 1 can be driven to rotate clockwise. A photoreceptor drum 501 is provided, around which a neutralizing lamp 506, a charging charger 502, an erase lamp 503, a first developing device 301,
A second developing device 302, a pre-transfer static elimination lamp 504, a transfer charger 404, a separation charger 405, and a blade type cleaning device 600 are provided. The photosensitive drum 501 is provided with a photosensitive layer on the surface. The photosensitive drum 501 is uniformly charged by the charge removing lamp 506 and the charging charger 502,
It receives image exposure from the optical system 100.

The optical system 100 is arranged so that the original image can be scanned below the contact glass 101, and includes a light source 102 and movable mirrors 105 and 10.
6, 107, 109 and 110, a lens 113 and a fixed mirror 112. The light source 102 and the movable mirror 105 move rightward at a speed of (V / m) (where m is the copy magnification) with respect to the peripheral speed (V) of the photosensitive drum 501, and move the movable mirrors 106 and 10.
7 is driven by a drive motor (not shown) so as to move at a speed of (V / 2m). The peripheral speed of the photoreceptor is constant irrespective of the magnification and the magnification. When changing the copy magnification, the lens 113 moves on the optical path and the mirrors 109 and 110 move to secure an optical path length corresponding to the magnification. Reference numeral 114 denotes a dust-proof glass that partitions the optical system 100 and the peripheral portion of the photosensitive drum 501.

On the other hand, on the right side of the copying machine body 1, call rollers 203 and 222, paper feed rollers 204 and 223, and separation rollers 205 and 224 are respectively provided.
Paper feed units 210 and 220 are provided, and the transfer path of the transfer paper is a pair of registration rollers 402, a suction transfer roller 407, and a fixing device 70.
0, composed of a main body discharge roller pair 801. 212,225
Is a paper size detection switch.

Before the pair of registration rollers 402, the pair of registration rollers 402
Registration roller front sensor 401 to control ON / OFF
Is provided.

A manual paper feed unit 201 is provided above the paper feed unit 210, and either one of manual paper feed and cassette paper feed can be used. The manual paper feed unit is provided with a size sensor (not shown) for detecting the size of the paper in the width direction. The manual paper feed unit is openable and closable. When opened, a sensor (not shown) for detecting the open / close state of a pressure arm (not shown) that presses paper in the cassette of the paper feed unit 210 is provided. Release the pressure and enable paper feeding from the manual feed section.

The transfer paper sent from the manual paper feed unit or the cassette paper feed unit is timed with the toner image on the photosensitive drum 501 by the registration roller pair 402, and the tree image is transferred to the upper surface by the transfer charger 404. It is separated from the photosensitive drum 501 by the separation charger 405. The peeled transfer paper is sent to the guide plate 701 of the fixing device 700 while being suctioned and conveyed by the suction conveyance roller 407, and the toner image on the upper surface is fixed by the fixing roller 704 and the pressure roller 705. The transfer paper after the fixing is separated from the fixing roller 704 by the separation claw 707, and reaches the fixing discharge roller pair 708.

When there is only one document, it is not necessary to discharge the paper on the back side.
And is discharged onto the discharge tray 802 via the main body discharge roller pair 801 at the position indicated by the solid line.

When there are a plurality of originals and one or a plurality of copies, it is necessary to discharge the back side in order to discharge the transfer paper in the page order. Gate 709 after the transfer paper exits the fixing discharge roller pair 708.
Is set to the position indicated by the solid line, and the gate 710 is set to the position indicated by the broken line, and the sheet is conveyed to the combined double-sided conveying roller (intermediate tray) 819 side. If the transfer paper is larger than A4 vertical size, it will reach the re-feed roller 805 if it is fed as it is.
Enter 809. The pressure driving roller 810 is rotated counterclockwise until the rear end of the transfer paper passes the sensor A814, and is conveyed.At the moment of passing, the rotation of the pressure driving roller 810 is stopped, and then the clockwise rotation is performed. Main body discharge roller pair 80
The stack is stacked on the paper discharge tray 802 with the copy side facing down from 1. When the transfer paper reaches the main body discharge roller pair 801, the pressure drive roller 810 stops the pressure drive and waits for the next transfer paper.

In this copying system, an original is fed in a page order by an automatic document feeder (ADF), which will be described later. Thus, when copying only one side, a copy in the page order can be obtained by setting the copy surface to the lower surface.

In this embodiment, as shown in FIG. 2, a double-sided and composite intermediate tray 819 is provided in the copying machine main body 1, and the transfer paper after fixing is turned and conveyed into the intermediate tray 819 during the synthesis, and At times, the conveyance path is switched and the sheet is introduced into the intermediate tray 819 from the sheet re-feeding side.

That is, in the duplex copying process, the transfer paper is guided to the duplex transport path 818 with the gate 709 positioned at the broken line. Intermediate tray 8
Turn the transfer paper from the refeed direction of
Send to 9. After the transfer paper has passed through the pair of pull-out rollers 812 on both sides, the jogging operation is performed by the jogger fluence 820 in a state where the leading edge of the transfer paper is urged against the paper feed roller 805 by pressing the intake roller 804 rotating counterclockwise. The stack on both sides of the large-size paper rotates the pressure driving roller 810 in the clockwise direction and pressurizes it to assist the conveyance. Transfer paper is
The sheet is separated one by one by a sheet feeding roller 805 and a separation roller 806, and reaches a registration roller pair 402 via a conveyance roller pair 408. Here, the transfer paper is stopped once, is synchronized with the image on the second surface of the photosensitive drum 501, and is conveyed again. The operation up to the fixing device 700 reaches the fixing discharge roller pair 708 by the same operation as that for one-sided copying. The gates 709 and 710 are both located at solid lines, and the transfer paper is directly
Is stacked on the paper discharge tray 802. This completes the stack with the first side down and the second side up.

In the composite copying step, the transfer paper introduced into the intermediate tray 819 by the operation of the gates 709 and 710 (solid line and broken line) is pressed by the pressure driving roller 810 rotating counterclockwise. When the leading edge of the transfer paper reaches the paper feed roller 805, the pressure is released. Also, for small-size paper, when the leading edge of the transfer paper reaches the position of the attraction roller 804, the attracting roller 804 is pressed downward, and when the leading edge of the transfer paper reaches the feed roller 805, the pressure is released.
Drive Jyoga Fuens 820 to align paper. After being jogged by the jogger fluence 820, the transfer paper is sent to the paper feed roller 805 and the separation roller 806 by the draw-in roller 804.
The transfer paper is separated by a feed roller 805 and a separation roller 806 into one.
The sheets are separated one by one and reach the registration roller pair 402 via the conveyance roller pair 408. Here, the transfer paper is stopped once, then is timed with the image to be combined on the second surface of the photosensitive drum 501, and is conveyed again. The operation up to the fixing device 700 reaches the fixing discharge roller pair 708 by the same operation as that for one-sided copying. When a single composite copy is to be obtained, the gates 709 and 710 are both located at the positions indicated by solid lines, and the transfer paper is directly transferred to the main body discharge roller pair.
After 801, the sheets are stacked on a paper discharge tray. When a plurality of composite copies are to be obtained, the sheet is discharged on the back side so that the pages are arranged in the same order as in the case of one side. That is, after the transfer paper exits the fixing discharge roller pair 708, the gate 709 is positioned at the solid line,
0 is a position indicated by a broken line and is conveyed to the intermediate tray 819 side. Until the trailing edge of the transfer paper passes the sensor A814, the pressure drive roller 810 is rotated counterclockwise and conveyed, and at the moment it passes, the rotation of the pressure drive roller 810 is stopped, and this time it rotates clockwise. Then, the original is stacked on the paper discharge tray 802 with the copy surface facing downward from the main body paper discharge roller pair 801.

As shown in FIG. 1, the copying machine main body 1 has two cassette paper feeding sections 210 and 220 and one manual paper feeding section 201. However, when feeding a larger number of paper sizes, Multi-stage paper feeder 90 that can be connected to the bottom
Use 0. The multi-stage paper feeding device 900 includes a third paper feeding unit 901, a fourth paper feeding unit 910, a fifth paper feeding unit 920, and a sixth paper feeding unit 930. Can also be used as a large-volume feeder (LCT) that can feed large amounts of transfer paper. The paper feeding method here is the same as that of the copier body, and all of them are call rollers 903, 913, 923, 933 and paper feed rollers 904, 914, 9
This is a reverse roller sheet feeding system including 24,934 and separation rollers 905,915,925,935. The roller pair 951,952 is for conveyance. The third and fourth paper feed units 901, 910 also have paper size detection switches 906, 916, 926, 936 so that the size of the paper stored in each cassette can be detected.

For example, assuming that the fourth paper cassette 910 has been selected, its operation will be described. First, several sheets of transfer paper are sent out by the rotation of the call roller 913, and the sheet feeding roller 914 that rotates counterclockwise and the separation roller 915 that is urged to rotate counterclockwise at a certain torque or less. As a result, only one transfer sheet is sent to the conveying roller pair 952. Thus, the transfer paper reaches the registration roller pair 402 via the conveyance roller pair 951. Since the transfer paper blocks the registration roller front sensor 401 on the way, the conveyance roller pair 951, 952 stops after a predetermined time. Thereafter, like the transfer paper fed from the other paper feeding unit of the copying machine main body 1, the photosensitive drum
It is transported again with the timing of the 501 image.

In this multi-stage paper feeding, a large-sized paper cassette is set on the left side and a small-sized cassette is set on the right side. However, this is not particularly necessary.
This is illustrated because such a structure is more balanced in the overall configuration. In the event that a jam occurs in the transport unit from the paper supply unit, the portion indicated by the dashed line 940 is opened to remove the jammed sheet in the transport unit.

As shown here, the four paper feeding units are arranged on the left and right sides so as to shorten the conveyance path as much as possible to shorten the paper conveyance time, and to dispose the cassette near the floor so as not to deteriorate the operability. This is because

FIG. 3 is a block diagram of the ADF 1000. The ADF is composed of a document feeder 1001, a transport unit 1019, a reversing unit 1012, and a paper discharge unit 1037.
04, a separation roller 1006, and a blocking roller 1007, and the pages are set in order from the top with the document surface facing upward. The transport unit 1019 is
Endless transport belt driven by belt drive roller 1021
1020 and belt fixing roller 1022, belt driven roller 1024 and belt pressure roller 1023, pull-out roller: drive 1025, pull-out roller: driven 1026, transport roller 1027, transport roller 10
Consists of 28 and so on. The reversing unit 1012 includes a reversing roller 1013, a driven roller 1014, a deflection claw 1015, and the like. The paper output unit 1037
Reverse discharge roller 1029, reverse discharge roller 1030, discharge guide roller
1031, a discharge roller 1033, a discharge roller 1034, and the like.

When a copy is obtained from the most common one-sided original, only one original D is loaded by the pull-out roller 1004, the separation roller 1006, and the blocking roller 1007.
The document is then conveyed to the contact glass 101 through the document reference scale 1018. The length of the fed document in the feed direction is determined by the detection sensor A1005,
Thus, the drive time of the conveyor belt 1020 is determined. This sensor A1005 also detects the presence or absence of a document. Conveyor belt 1020
After the trailing edge of the document D once passes through the document reference position 1038, the belt D is rotated clockwise by rotating the belt drive roller 1021 to move the transport belt 1020 to the left, thereby moving the document D to the position indicated by the solid line in FIG. It is abutted against a document reference scale 1018 and set at a document reference position 1038. The conveyance belt 1020 further rotates after the document D has hit the document reference scale 1018, and stops after correcting the registration and skew of the document D. At this time, the transport belt 1020 and the document slip. When the exposure by the optical system 100 is completed, the belt drive roller 1021 is driven to rotate counterclockwise, and the document D is conveyed rightward and sent to a pull-out roller: drive 1025 outside the contact glass 101. Here, the original D is inverted along the U-shaped guide shown in the figure, and the transport rollers 1027 and the transport rollers 102 in the transport section 1019 are rotated.
Conveyed by 8. In this case, the document D has an image surface facing upward. Further, the document D is inverted by the reverse discharge roller 1029, passes through the discharge guide rollers 1031, the discharge roller 1034, passes through the document discharge port 1035, and has an image surface on the lower side of the document receiver 1036 provided on the ADF. Is discharged above. With this operation, the originals D are stacked in page order with the original side facing down.

When a copy is obtained from the double-sided document D, the copy is made first from the front side, so that the process is the same from the sheet feeding to the time when the copy reaches the document reference scale 1018. After copying the front side, the belt driving roller 1021 is rotated clockwise to copy the back side, and the original D is inverted by the transport belt 1020 to the reversing unit 1012.
Send to Prior to this operation, the original reference scale 10
18 is centered on the fulcrum 1017 so as not to hinder the conveyance of the original D,
It rotates to the position shown by the broken line by a rotating mechanism including a solenoid, a spring, and the like, not shown. At this time, the document reference scale 1018 serves as a guide when the document D moves from the contact glass 101 to the reversing unit 1012. The original D includes the reversing roller 1013 and the deflecting claw 10 rotated to the position indicated by the solid line.
It is inverted by 15 and goes on the contact glass 101.

When the leading edge of the document D is detected by the sensor B1016, the belt driving roller 1021 rotates counterclockwise,
The original D is sent out onto the contact glass by moving 20 to the right. After that, the scanning starts after correcting the registration and skew of the document D in the same manner as when scanning the front surface.

After the copy on the back side is completed, the document D is sent to the reversing unit 1012 with the original reference scale 1018 avoiding the position indicated by the broken line in FIG. The deflecting claw 1015 is positioned at a broken line so that the document D does not re-enter the contact glass 101, and the document D travels from the reversing roller 1013 through the deflecting claw 1015 to the paper discharge section 1037. Reverse discharge roller 1029 and discharge roller 10
The original D is sent from the paper exit 1035 to the original receiver 1 on the ADF
Discharged at 036. Also in this case, the originals D are stacked in order from the first page, with the front side facing down, so that they are stacked as a bundle of the originals D in the same page order.

FIG. 4 is a block diagram of a control circuit according to the embodiment. The control circuit comprises a sequence controller 10, an operation controller 11, an AC controller 12, a motor controller 13, and an ARDF controller 14. The sequence controller 10
A timing control of input / output operations of a load 16 such as a sensor 15, a motor, a clutch, etc. relating to image formation and paper conveyance, and a mode control based on input data from a key 17 obtained from an operation controller 11 are performed. In addition, the sorter drive control is also performed,
The entire copier is controlled by serial communication with each controller. The operation controller 11 transmits the input data of the key 17 to the sequence controller 10 and controls the LCD display 18 based on the received mode data. The AC controller 12 controls the surface temperature of the fixing heat roller 19 and the voltage of the exposure lamp 20 by PI control. The motor controller 13 has a scanning scanner mode 21
Speed control and the position control of the lens and the mirror are performed via the motor 22. The ARDF controller 14 controls feeding, stopping, and discharging of the original by a load 23 such as a motor and a clutch in accordance with a command from the sequence controller 10.

Each of the controllers 10, 11, 12, 13, and 14 includes a CPU and peripheral LSIs and drivers, and controls the inputs of the sensor 15 and the loads 16 and 23 such as motors and solenoids. , 12, 13, and 14 perform synchronous control by serial communication. This configuration is known, and the sharing of the controller can be considered in other ways, and is not limited to the configuration shown in FIG.

 Here, the present embodiment will be described in more detail.

In FIG. 1, the transfer paper that has passed through the fixing device 700 after the image formation is normally discharged, with the gates 709 and 710 operated at the solid line position and discharged with the image surface facing upward. During double-sided operation, the gate 709 is operated at the position indicated by the broken line, and during synthesis, the gate 710 is operated at the position indicated by the broken line, and the transfer paper is guided to the intermediate tray 819.

On the other hand, in the back side discharge mode, the transfer paper that has completed the image formation and passed through the fixing device 700, including both sides and the combination, moves the gate 709 to the solid line position and the gate 710 to the broken line position as in the case of the combination. Insert the transfer paper into tray 819. At that time, the pressure drive roller 810 is rotated counterclockwise,
At the timing when the leading end of the transfer paper reaches the pressure drive roller 810, the transfer paper is pressed and inserted and conveyed on the intermediate tray 819. When the sensor A814 detects the rear end of the transfer sheet, the rotation direction of the pressurizing drive roller 810 in a pressurized state is reversed, and the transfer sheet is conveyed toward the discharge roller 801. When the transfer sheet enters the space between the discharge rollers 801, the pressure drive roller 810 releases the pressure, sets the rotation direction to the counterclockwise direction, and waits for the next transfer sheet.

Even in the case of a double-sided or multi-sided or back-side discharge mode at the time of combining, the operation can be performed because the transfer paper is inverted by inserting and discharging the transfer paper stacked on the intermediate tray 819.

FIG. 5 shows an operation timing chart at the time of back surface discharge according to the first embodiment. In FIG. 5, the main process linear velocity and the transfer paper transport linear velocity are 250 m as in the conventional example of FIG.
m / sec, and this is a case where the conveying linear speed to the introduction, discharge, and discharge to the intermediate tray 819 at the time of backside discharge is 500 mm / sec. Accordingly, the forward / reverse rotation of the pressure drive roller 810 and the rotational linear speed of the paper discharge roller 801 are set to 500 mm / sec.

In FIG. 5, the same operation as in FIG. 7 is performed until the transfer paper that has passed through the fixing paper discharge sensor (not shown) is driven by the pressure driving roller 810. When the leading edge of the transfer paper reaches the lower part of the pressure driving roller 810, the pressure solenoid of the pressure driving roller 810 rotating counterclockwise is turned on to pressurize. As a result, the transfer paper is introduced into the intermediate tray 819 at a linear rotation speed of the pressure driving roller 810 of 500 mm / sec. At this time, the transport relay roller 711 rotates freely in the transport direction, and the transport relay roller 711 rotates at a high speed so as to be pulled by the transfer paper. 500 m when the rear end is detected by sensor A814
The pressure drive roller 810 is rotated clockwise at a high speed of m / sec.
Discharge at a rate of sec. The transfer of the drive to the paper discharge roller 801 is detected by the paper discharge sensor 815, and the pressure of the pressure driving roller 810 is released to prepare for the introduction of the next transfer paper. As a result, the paper feeding interval was 1.5 cps, equivalent to 40 cpm, and the same productivity as front-side discharge was secured.

FIG. 6 shows an operation timing chart in the back side discharge mode according to the second embodiment. Figure 6 shows the intermediate tray
In the reversal of the transfer paper at 819, the next transfer paper is introduced during the discharge of the transfer paper, thereby shortening the interval between the transfer papers and increasing the productivity. In FIG. 6, the transfer paper transport speed is the same as the conventional example shown in FIG. 7, and only the control timing is converted.

The operation is basically the same as in FIG.
The control of the pressurization and the rotation direction is performed using the operation of the sensor A 814 and the paper discharge sensor 815 as a trigger.

By shortening the recency, following the transfer paper at early time points t ₄ from the timing t ₃ of the discharge end of the intermediate tray 819
, The transfer paper passes for a certain period of time while the transfer paper is being fed and discharged in an overlapped state. At this time, the discharge is performed by the discharge rollers 801
Then, the introduction is driven by the transfer relay roller 711, and when the trailing edge of the first transfer paper has already passed under the pressure driving roller 810 and the leading end of the second transfer paper reaches the lower part of the pressure driving roller 810, Drive by pressure. This timing t ₅ for releasing the pressure in front of the transfer sheet is achieved by earlier than the timing t ₄ when detecting the next leading edge of the transfer sheet by the sensor A814.

As a result, the paper feed interval was shortened to about 2.0 seconds,
The productivity at the time of back side discharge is improved.

〔The invention's effect〕

As described above, according to the first aspect of the present invention,
When the image forming paper (paper) is inverted and discharged, the image forming paper that has left the fixing unit is increased at a considerably higher rate than the previous conveying speed, and by repeating this, the interval between the successive image forming papers is reduced. Is reduced as much as possible, so that the productivity of image formation can be improved.

Further, according to the second aspect of the present invention, in the back-side discharge mode, the next sheet is carried in while the sheet is being sent from the holding position, thereby shortening the sheet feeding timing (sheet interval) of the continuous sheet feeding. And the productivity of image formation can be further improved.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a block diagram of an embodiment of an image forming apparatus according to the present invention, FIG. 2 is a block diagram showing an entire copying machine, FIG. 3 is a block diagram of an ADF, and FIG. Block diagram of control circuit, FIG. 5, FIG.
FIG. 7 is an operation timing chart of each section of the present embodiment, and FIG. 7 is an operation timing chart of each section of the conventional example. 802: paper ejection tray, 810: pressure drive roller, 819 ...
Intermediate tray.

Claims (2)

(57) [Claims] 1. An image forming apparatus comprising a reversing device for reversing and feeding a sheet discharged from a fixing unit to a discharge unit after a toner image is fixed on an upper surface, wherein the reversing device includes a sheet discharged from the fixing unit. A holding position for temporarily holding the entirety, and a pressure driving roller for sending out the sheet in the holding position toward the discharge unit and having a rotation speed higher than a linear speed in the image forming process. Image forming apparatus. 2. The pressurizing drive roller presses the paper so as to hold the second paper at the holding position while the first paper is being sent from the holding position to the discharge section. And an image forming apparatus for performing pressure release, normal rotation, and reversal.