JPH07191592A - Paper feeding device in image forming device - Google Patents

Abstract

PURPOSE:To shorten time required for a first copy at the time of applying a power source or starting a copy in a type that the consumption of electric power is reduced. CONSTITUTION:A controller 150 driving a manually feeding roller 114a or one of the pickup rollers 118a-118c from the first to the third at the time of applying the power source of a device main body 101 is provided. Thus, a paper sheet can be previously carried up to a resist roller 120 during warming up an operation for forming an image on a photoreceptor 104 can be immediately executed without waiting for the arrival of the paper at the resist roller 120 at the time of starting the copy and the first copy time can be shortened by a waiting time for the arrival of the paper.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a sheet feeding device in an electrophotographic apparatus or the like, in which a sheet can be taken out before starting an image forming operation.

[0002]

2. Description of the Related Art In an image forming apparatus such as an electrophotographic apparatus, a heat roller whose temperature has been lowered is raised to a fixing temperature while warming up by turning on a power source or while waiting for copying to save power consumption. In return mode,
After finishing the warm-up or return mode without feeding the paper for the first copy,
When the copy key is turned on, copying is started and the paper feeding operation is started.

[0003]

Conventionally, the paper feeding for the first copy is performed only after the copy key is turned on.

Therefore, particularly in the first copy when the power is turned on or when the copy operation of the power saving type is started, the copy is started until the end of the warm-up until the heat roller reaches the fixable temperature or the end of the return mode. There is a problem that it takes time to obtain a copy because it takes a normal copying time in addition to waiting.

Even during normal copying from the ready state, in the first copy, the image forming operation on the photosensitive member is performed at the same timing as the paper is conveyed to the registration rollers. It took some time compared to the copy time after the first copy.

Therefore, the present invention eliminates the above-mentioned problem. In the first copy, after the copy operation is started,
First of all, it is not necessary to wait for the image forming operation on the photoconductor so as to match the timing when the paper arrives at the registration roller. By turning on the copy key, the image forming operation on the photoconductor can be started immediately and the paper arrives. It is an object of the present invention to provide a sheet feeding device in an image forming apparatus with high functionality, which can reduce the time required for first copy by waiting, and can achieve higher speed.

[0007]

In order to solve the above-mentioned problems, the present invention provides a main body of an apparatus having an image forming means, a paper feeding means provided in the main body of the apparatus, and a paper feeding means from the paper feeding means to the image forming means. A sheet conveying path that passes through the image carrier and reaches the paper discharge unit, and a sheet that is provided between the sheet supplying unit and the image carrier in the sheet conveying path and that is supplied from the sheet supplying unit. A registration roller that conveys in synchronization with the developer image formed above, a conveyance unit that conveys the paper from the paper supply unit to the registration roller, and a conveyance unit that operates when the apparatus main body warms up. A control means for controlling the above is provided.

[0008]

The present invention is configured as described above, and the paper is carried to the registration roller before the start of the copying operation by activating the carrying means in advance when the power is turned on or in the power saving type return mode. When the subsequent copy operation is started, the image forming operation on the image carrier can be immediately performed, and the speed of the first copy can be increased.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. Further, 3 is a document table 4 is a cover.

FIG. 1 shows an image forming apparatus having an image forming means 2. A drum-shaped photoconductor 10 which is an image carrier is provided in the main body 1 of the image forming device.
The image forming means 2 is provided with a charging device 11, an exposure unit 12a of the exposure device 12, a developing device 13, a transfer peeling charger 14, a cleaning device 16, and a charge eliminating device 17 around the periphery of the image forming means 2 along the rotation direction thereof. Are configured. Further, 3 is a document table and 4 is a cover. Below the image forming means 2,
A paper feed cassette device 18 which is a paper feed means is provided,
Further, a manual feed tray 30 is provided on the right side of the apparatus body 1. The paper cassette device 1
A sheet conveying path 20 for guiding the sheet 8 or the sheet fed from the manual feeding tray 30 to the sheet discharging tray 9 which is a sheet discharging portion provided on the left side of the apparatus main body 1 via the photoconductor 10 is formed. Incidentally, reference numeral 30a denotes a manual feed detection switch for detecting the presence or absence of paper on the manual feed tray.

On the upstream side of the photoconductor 10 in the sheet conveying path 20, a manual feed roller 30b and a pickup roller 8 which are conveying means, first and second separating rollers 9a and 9b, and a pickup roller 8 are provided. The paper taken out from the paper cassette device 18 and the paper taken out from the manual feed tray 30 by the feed roller 30b are temporarily stopped before the photoconductor 10 via the separation rollers 9a and 9b, and the leading ends are aligned so that A registration roller 21 that conveys the toner image again while synchronizing with the toner image formed on the above is disposed. 21a is a registration roller 2
2 is a first paper detection switch for detecting the presence / absence of paper in No. 1.

It should be noted that the pickup roller 8 is not only actuated for paper supply during normal copying, but is also actuated by the control device 50 described later during warm-up after the power switch (not shown) is turned on. It has become.

On the other hand, on the downstream side of the photoconductor 10 in the paper transport path 20, a transport belt 22 for transporting the paper P from the transfer position to the fixing position, and a heating roller 24a having a heater 23 built therein.
And a pair of fixing rollers 24, which are pressure rollers 24b that are pressed against the heating rollers 24a, a transport roller 26, and a paper discharge roller 27. 27a is the discharge roller 2
7 is a second sheet detection switch that detects arrival of a sheet at 7 and sheet ejection.

Here, the fixing roller 24 is temperature-controlled so as to maintain the fixing temperature of 210 ° C. to 230 ° C. during the copying operation, while it is reduced to 180 ° C. to save power consumption during the copying standby. The temperature is controlled so that

Further, an operation panel 2 is provided on the upper surface of the apparatus main body 1.
8 is provided, and a copy key 28a for instructing the start of copy operation, a numeric keypad 28b for setting the number of copies, a density adjustment key 28c, and a magnification key 28 are provided on the operation panel 28.
Various keys such as d and original size key 28e are provided.

FIG. 3 is a block diagram showing a control system. The control device 50 for controlling the main body 1 of the apparatus is provided with a copy-2 on the operation panel 28 via an input interface 51.
8a, ten keys 28b, magnification key 28d, etc.
Signals are input from various switches / sensors 52, etc. for detecting the paper in the paper transport path 20, the feed timing, the toner density, etc. such as the first, first and second paper detection switches 21a and 27a. Has been done.

On the other hand, the controller 50 outputs the output interface 5
3, the image forming unit 2 such as the photoconductor 10 of the apparatus main body 1, the developing device 13 or the exposure device 12, the fixing roller 24, and various motors such as the pickup roller 8, the manual feed roller 30, and the registration roller 21. It is connected to a motor driver 56 that drives 54 and a display unit 57 on the operation panel 28 to control it.

Then, the controller 50 controls the heating of the heat roller 24 to a fixing possible temperature at the time of warming up after the power switch (not shown) is turned on, and also controls the pickup roller 8 or the manual feed roller 30a on the paper transport path 20. The sheet is conveyed to the registration roller 21 when operated.

Further, the control device 50 controls the pickup roller 8 even while waiting for the next copy after the image forming operation is completed.
Is operated to convey the paper to the registration roller 21.

If the paper previously conveyed to the registration roller 21 after the completion of the previous copy is different from the paper supplied from the manual feed tray 30 at the time of the next copy, the control device 50 will cause the registration roller 21 and the conveyance belt 22. , The fixing roller 24, the conveyance roller 26, and the paper discharge roller 27 are driven to forcibly discharge the previously conveyed paper, and the manual feed tray 3
The paper will be conveyed again from 0.

Next, the operation will be described.

At the start of copying, when a power switch (not shown) provided in the apparatus main body 1 is turned on, initialization is performed by the control device 50, and warming up for heating the heating roller 24a up to 220 ° C. which is a fixing temperature is performed. When the sheet is placed on the manual feed tray 30 and the manual feed detection switch 30b is switched after waiting for a predetermined time, for example, 15 seconds, when the manual feed is started, the manual feed roller 30b is driven. The pickup roller 8 is driven, the paper is taken out from the manual feed tray 30 or the paper feed cassette device 18, is conveyed to the registration roller 21, and is on standby. At this time, the operation of the first paper detection switch 21a is stopped.

On the other hand, during this period, the operator operates the operation panel 2
Input necessary image forming conditions from above and wait for the end of warming up. After that, when the warm-up is completed and the ready display is displayed on the display unit 57, the operator turns on the copy key 28a to immediately start copying. However, at this time, the sheet is already on standby at the registration roller 21 position. The image forming unit 2 immediately starts the image forming operation on the photoconductor 10 without timing the arrival of the sheet. That is, when the copy key 28a is turned on, the steps of charging, exposing and developing are immediately performed on the photoconductor 10 to form a toner image on the surface thereof. Then, the sheet waiting at the position of the registration roller 21 is sent to the transfer position by the drive of the registration roller 21 in synchronization with the arrival of the toner image on the photoconductor 10 at the transfer peeling charger 14, and the paper on the photoconductor 10 is transferred. The toner image is transferred.

After that, the sheet on which the toner image has been transferred is separated from the photoconductor 10 and conveyed by the conveyor belt 22.
After being sent to the fixing roller 24 to fix the toner image,
The sheets are stacked on the sheet discharge tray 9 by the sheet discharge rollers 27. At this time, the first and second paper detection switches 21a, 2
7a is operated to detect a paper jam.

After the transfer is completed, the photoconductor 10 is made ready for the next copy through the cleaning device 16 and the static eliminator 17, and the copy forming operation is repeated until the required number of copies is reached. When all the copying operations are completed in this way, the image forming means 2 is stopped, and in addition to this, in the fixing roller 24, the controller 50 causes the surface temperature to rise from the fixable temperature. The temperature is controlled so as to maintain 180 ° C., which is the temperature during the standby period. For the next copy operation,
The pickup device 8 is driven by the controller 50,
The paper is taken out from the paper feed cassette device 18 and waits for the next copy operation while waiting at the position of the registration roller 21.

When the next copy is fed from the manual feed tray 30, the control device 50 controls the registration roller 21,
The conveyance belt 22, the fixing roller 24, the conveyance roller 26, and the paper discharge roller 27 are driven to forcibly discharge the paper waiting in the registration roller position in advance, and then the copy operation is started again, and the paper is fed from the manual feed tray 30. Will be supplied.

According to this structure, the sheet can be conveyed to the registration roller 21 in advance during warming up after the power is turned on, and at the start of copying after the warming up, the image forming step on the image carrier is immediately performed without waiting for sheet conveyance. Since it can start, the time required for the first copy after the power is turned on can be shortened. Further, in this embodiment, the temperature of the fixing roller 24 is lowered at the time of standby for copying in order to save power consumption, and it is necessary to wait for the temperature to return to the fixable temperature at the start of the next copying. Since the sheet has been conveyed to the registration roller 24 in advance for the next copy operation after the end of the previous copy, the image forming process can be started immediately after the end of the return mode, and the sheet conveyance is waited for, like when the power is turned on. There is no need, and the first copy time can be shortened.

In the present embodiment, after copying is completed,
Waiting for the next copy in the state where the paper for the next copy operation has been conveyed in advance, but the paper is conveyed to the registration rollers when the next copy is started, not in the end of the copy, but in the return mode standby. You can

Next, a second embodiment of the present invention will be described with reference to FIGS.
Will be described with reference to.

FIG. 4 shows the image forming apparatus 100 as a whole, and is a sheet supply unit for detachably supporting the apparatus main body 101 having the image forming unit 102 and the first to third sheet feeding cassette units 7a to 7c which are sheet feeding units. It consists of a paper unit 7.

A drum-shaped photosensitive member 104, which is an image bearing member, is provided substantially in the center of the apparatus main body 101, and the charging device 106 is provided around the photosensitive member 104 along the rotation direction thereof. Exposure unit 107 of exposure apparatus 107
a, a developing device 108, a transfer peeling charger 110, a cleaning device 111, and a charge eliminating device 112 are provided to constitute an image forming means 113. Reference numeral 97 is a document table, and 98 is a cover.

On the right side of the apparatus main body 101, a manual paper feed tray 114 for manual paper feed is provided. On the other hand, the paper feeding unit 7 is equipped with first to third paper feeding cassette devices 7a to 7c, which are paper feeding means and accommodate a paper P of an arbitrary size. Then, in the apparatus main body 101, the paper sheet fed from the manual feed tray 114 or each of the first to third paper feeding cassette apparatuses 7a to 7c is provided on the left side of the apparatus main body 101 via the photoconductor 104. A paper transport path 117 that leads to the paper discharge tray 116 is formed. Note that reference numeral 114b denotes a manual feed detection switch that detects the presence or absence of paper on the manual feed tray 114.

The manual feed roller 114a and the first to third pickup rollers 11 which constitute a conveying means are provided on the upstream side of the photosensitive member 104 in the sheet conveying path 117.
Sheets taken out from the manual feed tray 114 and each of the sheet feeding cassette devices 7a to 7c by 8a to 118c are separated by the first to fourth separation rollers 5a to 5d, and first and second transmissions forming a conveying unit. Through rollers 6a and 6b,
First to fourth conveyance paths 117 for guiding to the photoconductor 104
a to 117d are formed. Further, the paper transport path 117
Before the photoconductor 104 of, the front end of the paper is aligned and the photoconductor 1
A registration roller 120 that conveys a sheet in synchronization with the toner image formed on the sheet 04 is disposed. Again 12
Reference numeral 0a is a first paper detection switch for detecting the presence or absence of paper on the registration roller 120.

Then, the first to fourth transport paths 117a to 117a
17d is not only selectively operated for paper supply during normal copying, but is also operated by the control device 101 described later during warm-up after the power switch (not shown) is turned on. There is.

On the other hand, on the downstream side of the photosensitive member 104 in the paper transport path 117, the transport belt 121 for transporting the paper P from the transfer position to the fixing position, the heating roller 123a containing the heater 122, and the heating roller 123a are pressed against each other. A pair of fixing rollers 123 composed of a pressure roller 123b and a conveying roller.
A roller 124 and a paper discharge roller 126 are provided. Again 1
Reference numeral 26a denotes a second paper detection switch for detecting arrival and discharge of the paper at the paper discharge roller 126.

Here, the fixing roller 123 is controlled so as to maintain the fixing temperature of 210 ° C. to 230 ° C. during the copying operation.

An operation panel 127 is provided on the upper surface of the apparatus main body 101. On the operation panel 127, a copy key 127a for instructing the start of a copy operation, and a numeric keypad 127b for setting the number of copies and the like. , A paper size selection key -1, which is a setting means for setting the size of the paper to be previously conveyed to the registration rollers or the size of the paper to be conveyed at the time of copying
Various keys such as 27c, density adjustment key-127d, magnification key-127e, and document size key-127f are provided.

FIG. 6 is a block diagram showing a control system. The control device 128 for controlling the entire image forming apparatus 100 including the apparatus main body 101 and the paper feeding unit 7 is on the operation panel 127 via the input interface 130. Copy key-127a, numeric keypad 127b, input key 131 such as paper size selection key-127c, first and second paper detection switches 120a and 126a, and detection of paper in the paper transport path 117 and detection of feed timing. Alternatively, signals are input from various switches / sensors 132, etc. for detecting the toner density.

On the other hand, the control device 128, via the output interface 133, the photosensitive member 104 of the main body 101 of the apparatus, the developing device 108 or the exposure device 107, the conveyor belt 12
1, the image forming means 102 such as the fixing roller 123, the motor driver 136 for driving the various motors 134 such as the paper feeding unit 7, and the display unit 137 on the operation panel 127.
It is connected to and controls it.

Further, the controller 128 controls the temperature of the heat roller 123 at the time of warming up after the power switch (not shown) is turned on, and at the same time, the paper transport path 117.
Upper first to third pickup rollers 118a to 11
8c, manual feed roller 114a and first to third
Selectively operating the transmission rollers 138a to 138c of
The sheet is conveyed to the registration roller 120. That is, when the manual feed tray 114 or one of the paper feed cassette devices 7a to 7c is set by the paper size selection key 127c when the power is turned on, the set paper is conveyed while the paper size is set. If not, the standard-size paper, which is set in the priority order set in the program in advance, is conveyed.

Further, after the image forming operation is completed, the control device 128 waits for the next copy, and then the first to third pickup rollers 118a to 118 on the sheet conveying path 117 are provided.
c, manual feed roller 114a, and first to third
Selectively operating the transmission rollers 138a to 138c of
The sheet is conveyed to the registration roller 120.

When the paper size previously conveyed to the registration roller 120 position before the start of copying in this way is different from the paper size set at the time of the next copy, the control device 128 controls the registration roller 120 and the conveyance belt 121. ,
Fixing roller 123, transport roller 124, paper discharge roller 12
6 is driven, the previously conveyed sheet is forcibly discharged once, and the sheet size set next is conveyed again.

Next, the operation will be described with reference to the flowchart shown in FIG.

When a power switch (not shown) provided in the apparatus main body 1 is turned on at the start of copying, the control device 128
The initialization is performed by step S150, and the warm-up for heating the heating roller 24a to 220 ° C., which is the fixing temperature, is started in step 150, and the paper size input is displayed on the display unit 137. This allows the operator to select the paper size selection key 127c as necessary within a predetermined time.
Enter more paper size. When the paper size is not input, the most frequently used paper, for example, A4 size paper, which is set in advance in the program, is selected as the standard size. Also, other image forming conditions are sequentially input.

Next, at step 151, a predetermined time, for example, 3
Whether 0 seconds has elapsed is compared, and if it has elapsed, the process proceeds to step 152 regardless of whether or not the image forming condition including the paper size is input. In step 152, whether or not the manual feed tray 114 is set by the manual feed detection switch 114b is compared. If it is set, the process proceeds to step 153, and if not, the process proceeds to step 154.

In step 153, the manual feed roller 114a and the first separating roller 5a are turned on to convey the paper on the manual feed tray 114 to the registration rollers 120, and the process proceeds to step 158. At this time, the first sheet detection switch 120a is not operated. On the other hand, in step 154, it is compared whether or not the paper size is selected by the paper size selection key 127c. If not selected, the process proceeds to step 156, and if selected, the process proceeds to step 157.

In step 156, the paper is taken out from the first paper feeding cassette device 7a in which the standard size A4 size paper set in the program is stored.
The first pickup roller 118a and the second separation roller 5b are turned on, the sheet is conveyed to the registration roller 120, and the process proceeds to step 158. On the other hand, in step 157, one of the first to third pickup rollers 118a to 118c and the second to fourth separation rollers is turned on according to the selected sheet, and the sheet of the selected size is conveyed to the registration roller 120. Proceed to step 158. At this time, the first detection switch 120a is not activated. In step 158, it is compared whether or not the warm-up is completed,
After waiting for the end, the process proceeds to step 160 and the display unit 1
A ready display is made at 37 to display the blanks that can be copied.

Next, at step 161, the copy key 12
7a is turned on and the process proceeds to step 162. In step 162, the paper size conveyed during warming up,
Whether or not the paper size input under the copy condition is matched is compared. If they do not match, the process proceeds to step 163, and if they match, the process proceeds to step 164.

At step 163, the registration roller 12
0, the conveyance belt 121, the fixing roller 123, the conveyance roller 124, and the paper discharge roller 126 are driven to forcibly discharge the paper conveyed to the registration roller 120 during warm-up to the paper discharge tray 116, and then the process proceeds to step 166. In step 166, copying is started, but since the paper is not conveyed to the registration rollers 120, the paper feeding of the paper of the size set by the copy condition is started first, and then,
The image forming operation on the photoconductor 104 is started at the timing when the paper reaches the registration roller 120.

That is, the photosensitive member 104 is sequentially charged, exposed, and
Each step of development is carried out and a toner image is formed on the surface thereof. Then, the sheet waiting at the position of the registration roller 120 is synchronized with the arrival of the toner image on the photoconductor 104 at the transfer peeling charger 110 in synchronization with the registration roller 120.
Is sent to the transfer position and the toner image on the photoconductor 104 is transferred.

After that, the sheet on which the toner image is transferred is peeled off from the photosensitive member 104, conveyed by the conveying belt 121, sent to the fixing roller 123, and fixed with the toner image, and then discharged by the paper discharging roller 126. The sheets are stacked on the paper tray 116. During this time, the first and second paper detection switches 120a and 126a are operated to detect paper jam.

After the transfer is completed, the photosensitive member 104 is made ready for the next copy through the cleaning device 111 and the static eliminator 112, and the copy forming operation is repeated until the required number of copies is reached. When all copy operations are completed in this way, the process proceeds to step 168. On the other hand, step 164
However, copying is started, but at this time, since the paper has already been conveyed to the registration roller 120, the photoconductor 10
4 starts the image forming operation on the upper side. The image forming operation is the same as step 167. When all copy operations are completed, the process proceeds to step 168.

In step 168, the standard size A.4 size sheet is conveyed to the registration rollers 120 for the next copy operation, and then in step 169, the display unit 1 is displayed.
A ready display is given to 37 and the apparatus main body 101 is set to the ready state, and the next copy is awaited.

When the next copy condition is input at step 170 and the copy key 127a is turned on, the process returns to step 162 to start the next copy operation.

With this configuration, as in the first embodiment, the paper can be conveyed to the registration roller 120 in advance during warming up after the power is turned on, and at the start of copying after the warming up, the image is immediately transferred without waiting for paper conveyance. Since the forming process can be started, the time required for the first copy after the power is turned on can be shortened by waiting for the arrival of the paper. Further, after the copy is completed, the paper is previously conveyed to the registration roller 120 for the next copy operation, so that the image forming process on the photoconductor 104 can be started immediately when the copy key is turned on, and when the power is turned on. Similarly, the length-first copy time can be shortened by waiting for paper conveyance.

In particular, when copying is performed with the paper stored in the first paper feeding cassette device 7a below the paper feeding unit 7, the distance to the registration roller 120 is long and the first copy can be more effectively shortened. .

Further, in the present embodiment, when the standard size paper conveyed during warm-up or during the next copy standby is different from the paper input under the copy condition, the paper previously conveyed is immediately forced. Since the paper can be discharged and new paper can be supplied, the copy operation is not hindered.

The present invention is not limited to the above embodiment, and various design changes are possible, for example, the number of paper feed cassette devices is arbitrary, and the standard paper size can also be changed. Further, the size of the paper conveyed to the registration rollers in advance may be set by reading the size of the original placed on the original table.

[0059]

As described above, according to the present invention, the paper can be conveyed in advance to the registration roller position at the time of warming up after the power is turned on or in the return mode after the start of copying in the power saving type, so that the warming up is completed. Alternatively, in the first copy following the end of the return mode, the image forming operation can be immediately performed on the photoconductor without waiting for the timing when the paper arrives at the registration rollers, and the first copy time is shortened by waiting for the arrival of the paper compared with the conventional method. it can. In particular, when the paper is fed by using the multi-stage paper feeding means, the distance from the paper feeding means to the registration roller becomes long, so that the first copy time can be more effectively shortened and the speed can be further increased. You can plan.

[Brief description of drawings]

FIG. 1 is a configuration diagram showing a device body of a first embodiment of the present invention.

FIG. 2 is a plan view showing an operation panel according to the first embodiment of the present invention.

FIG. 3 is a block diagram showing an apparatus main body according to the first embodiment of the present invention.

FIG. 4 is a configuration diagram showing an apparatus main body according to a second embodiment of the present invention.

FIG. 5 is a plan view showing an operation panel according to a second embodiment of the present invention.

FIG. 6 is a block diagram showing an apparatus main body according to a second embodiment of the present invention.

FIG. 7 is a flow chart showing a copy operation of the second embodiment of the present invention.

[Explanation of symbols]

 101 ... Device main body 102 ... Image forming means 7a to 7c ... First to third paper feeding cassette device 117 ... Paper transport path 120 ... Registration roller

Claims (3)

[Claims] 1. An apparatus main body having an image forming means, a paper supply means provided in the apparatus main body, and a paper conveyance path from the paper supply means to an ejection section via an image carrier of the image forming means. A registrar that is provided between the sheet supply means and the image carrier in the sheet transport path and that transports the sheet supplied from the sheet supply means in synchronization with the developer image formed on the image carrier. A transfer unit configured to transfer the sheet from the sheet supply unit to the registration roller; and a control unit configured to control the transfer unit to operate when the apparatus main body warms up. Paper feeding device in the image forming apparatus. 2. A main body of an apparatus having an image forming means, a paper feeding means provided in the main body of the apparatus, and a paper conveyance path from the paper feeding means to an ejection section via an image carrier of the image forming means, A registrar that is provided between the sheet supply means and the image carrier in the sheet transport path and that transports the sheet supplied from the sheet supply means in synchronization with the developer image formed on the image carrier. -A, a conveying unit that conveys the sheet from the sheet supplying unit to the registration roller, and a control unit that controls the conveying unit to operate after the image forming operation by the image forming unit is completed. A sheet feeding device in a characteristic image forming apparatus. 3. A paper supply means and a conveyance means supply means are provided in a plurality, and a setting means for setting an arbitrary paper supply means of the plurality of paper supply means is provided, and a control means is set by the setting means. 3. The sheet feeding device in the image forming apparatus according to claim 1, wherein the sheet feeding device in the image forming apparatus is controlled so as to operate an arbitrary conveying unit that takes out a sheet from the arbitrary sheet feeding unit.