JPH04371461A - Sheet feeder - Google Patents

Abstract

PURPOSE:To speed up recording by rapidly moving to a re-feeding action of a sheet for the next recording processing in executing continuous recording processing again on a plurality of sheets which have been recording processed after executing continuous recording processing on the plurality of sheets. CONSTITUTION:Immediately above an intermediate tray 110 for storing a sheet P1 which was given recording processing on one face, a paper pressing body PR is provided which takes a pressing position to press the sheet P1 stacked in this intermediate tray 110 from above and a non-pressing position not to press it alternately by a rotary action, and each time the sheet P1 which was recording processed on one face is stacked in the intermediate tray 110, the paper pressing body PR is rotated to press it, and the sheet pressed in the intermediate tray 110 is fed by a feeding roller R2 one by one.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a sheet feeding device in a printing device, an electrophotographic copying machine, etc., which has the function of printing or copying sheet paper (hereinafter referred to as a sheet) on both the front and back sides or on one side. Regarding.

0002

2. Description of the Related Art In recent years, image recording apparatuses such as electrophotographic copying machines have been realized which can record images on both the front and back sides of a sheet. In this type of device, after an image is recorded on one side of a sheet in the image processing unit, the sheet with one side recorded is temporarily stocked, and then the paper is fed to the image processing unit again in order to record the image on the other side. This type of automatic paper circulation feeding device was developed in Japanese Patent Application Laid-Open No. 59-822.
No. 47, JP-A-59-114227, JP-A-60-2
No. 241 and JP-A-62-161641. In such a device, a sheet recorded on one side in the image processing section is once conveyed below the image processing section and stored in the stacker section, then the sheet is sent out from the stacker section, conveyed upward, and then returned to the image processing section. By feeding paper, recording is performed on the other side of the sheet.

[0003] In addition, in an automatic single-sided multiplex recording device, a single-sided recorded sheet is stored in a stacker without being reversed, the sheet is sent out from the stacker section, conveyed upward, and then fed again to the image processing section. Recording is performed multiple times on one side of the sheet.

0004

[Problem to be Solved by the Invention] However, when double-sided recording or single-sided multiple recording is performed continuously on multiple sheets using the above-mentioned apparatus, it is difficult to feed the recorded sheets to the image processing unit again. After all the recorded sheets were stored in the stacker section, they were fed one by one toward the image processing section.

[0005] For this reason, after the previous continuous recording on a plurality of sheets ends, there is a long waiting time until the next continuous recording starts on each recorded sheet, and there is a limit to increasing the recording speed. Ta.

[0006] The present invention has been made in view of the above points, and an object of the present invention is to:
It is an object of the present invention to provide a sheet feeding device that can quickly shift to a sheet feeding operation for re-recording processing.

[0007]

[Means for Solving the Problems] In order to achieve the above object, the present invention provides a stacking means for continuously performing recording processing on a plurality of sheets of paper that have already been subjected to recording processing. In a sheet feeding device that sequentially sends a plurality of processed sheets of paper from the stacking means to the recording processing means, the sheet feeding device contacts the lowest sheet of paper stacked on the stacking means and removes the sheet of paper from the stacking means. a feeding device that sequentially feeds out sheets of paper; a paper pressing device that takes a pressed state and a non-pressed state with respect to the sheet-like paper in the stacking device; and when the number of sheet-like papers set as continuous recording targets is less than or equal to a predetermined number; a paper pressing control means that activates and presses the paper pressing means each time a sheet of paper is stacked on the stacking means; and after the sheet of paper is pressed under the control of the paper pressing control means, the feeding means and a feed-out control means that is activated to start the feed-out operation of the sheet-like paper.

[0008]

[Operation] For example, assume that the double-sided copy mode is set in an electrophotographic copying machine equipped with the present sheet feeding device, and the number of sheets to be double-sided copied is set to seven.

In this case, the sheet-like paper whose surface has been copied by the recording processing means is not discharged to the outside of the electrophotographic copying machine, but is transported toward the stacking means inside the electrophotographic copying machine. be accommodated. At this time, the sheet-like paper whose front side has been copied is dropped onto the paper pressing means and is in a non-pressed state. In addition, if the number of sheets set as the number of sheets to be double-sided copied is as small as 7, considering the time required for transportation from the stacking means to the recording processing means, it is recommended to immediately press the first sheet and re-feed it. If you are not prepared for this, the time interval between continuous copying on the front side and continuous copying on the back side will be longer than the time interval during continuous copying on the normal front side or back side. Therefore, the paper pressing control means starts and presses the paper pressing means every time a sheet of paper is stacked on the stacking means. That is, the paper pressing means is started at the same time when the first sheet of paper is stored in the stacking means, and the paper pressing means is started immediately when subsequent sheets of paper are stored in the stacking means. Ru. Then, after the first sheet of paper is pressed under the control of the paper pressing control means, the feeding control means activates the feeding means to start the feeding operation of the sheet of paper.

[0010] Then, at the timing when the recording processing means finishes copying onto the front surface of the seventh and final sheet, the first sheet of paper whose front surface has been copied is conveyed to the position of the recording processing means. Therefore, the transition from front side recording to back side recording is quickly performed.

[0011]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of a sheet feeding apparatus according to the present invention will be described with reference to the drawings.

FIG. 1 is an overall configuration diagram of an electrophotographic copying machine using a sheet feeding device according to the present invention.

This electrophotographic copying machine includes a copying machine main body 100 having a double-sided copy function, an automatic document feeder 200 that automatically transports a plurality of originals one by one to predetermined positions in the copying machine main body 100, and a copying machine main body 100 that has a double-sided copying function. Multiple sheets P to the machine body 100
1 and an automatic paper feeder 300 that automatically feeds paper sheets one by one.

The copying machine main body 100 includes a scanning exposure section A, an image forming section B, a paper feeding section C, a conveyance section D, a fixing section E, a paper ejection section F,
It has a paper discharge tray G, a stacker introduction section H, an automatic reversing and refeeding unit (ADU) I, an intermediate conveyance section J, and a paper supply section C,
The conveyance section D, the paper discharge section F, the stacker introduction section H, the automatic reversing and refeeding unit (ADU) I, and the intermediate conveyance section J include a group of rollers for sheet conveyance.

[0015] The dashed line in the figure shows the transport path of the sheet P1, and when the double-sided copy mode is set, the sheet P1 that has been copied on one side is reversed during the transport process and transferred to the image forming section B. The paper will be re-fed. That is, in the sheet P1 immediately after one-sided copying is performed in the image forming section B, the copied side is on the top as indicated by the bold line A in the figure. Then, during the conveyance process by the conveyance section D, paper discharge section F, and stacker introducing section
) I is stacked in an inverted state (see B and C in the figure). The sheet P1 sent out from the automatic reversing and refeeding device (ADU) I is immediately reversed again (see d in the figure). Then, during the conveyance process by the intermediate conveyance section J, it is reversed again (
(See E in the figure) By being re-fed to the image forming section B, the sheet is eventually re-fed to the image forming section B with the opposite side to the previous one serving as the copy side.

The automatic document feeder 200 includes a main body 1 of a copying machine.
It is removably installed on the original platen 101 of the copying machine 100, and the original P is
It is equipped with the function of reversing and conveying 2. Original table 201
The document P2 placed thereon is conveyed to the document table 101 by a group of conveyance rollers 202, and is copied by the copying machine main body 100. When the single-sided copy mode is set, after the copying machine main body 100 completes single-sided copying for the set number of sheets, the conveyor belt 203 transports the single-sided copies to the paper ejection tray 205. On the other hand, when the double-sided copy mode is set, the copying machine main body 100 completes single-sided copying for the set number of sheets, and at the same time, the conveyor belt 203 is reversed and the document P2 is conveyed to the reversing conveyance section 204, where it is reversed. The document is then conveyed to the document table 101 again, and the back side is copied. Then, the original P2 whose back side has been copied is conveyed toward the paper ejection table 205.

The automatic paper feeder 300 controls a paper feed clutch (not shown) to turn on/off transmission of the rotation of a paper feed motor (not shown) to the paper feed roller 301, thereby allowing the automatic document feeder 200 to feed documents. As sheet P2 is conveyed to the position of document table 101, sheet P1
are sequentially supplied to the copying machine main body 100 one by one. however,
When double-sided copy mode is set, sheet P1
The sheet P1 is fed in conjunction only while copying is being performed on the front side of sheet P1, and the sheet P1 is being fed while copying is being performed on the back side of sheet P1.
Stop the supply of 1. Note that the automatic paper feeder 300 has 3
Two paper feed trays 302 can be set, and each paper feed tray 30
2 can accommodate sheets P1 of different sizes.

In synchronization with the document P2 being conveyed to the document table 101 by the automatic document feeder 200, the sheet P1 is fed into the copying machine main body 100 by the automatic document feeder 300, and a message to that effect is displayed. It is detected by the paper feed sensor PS4. Then, when the sheet is conveyed to the image forming section B by the paper feeding section C in the copying machine main body 100, this is detected by the registration sensor PS5, and scanning exposure is performed by the scanning exposure section A. That is, upon receiving a detection signal from the registration sensor PS5, the scanning exposure section A turns on the illumination lamp 10.
A scanning system 104 consisting of a mirror 103 and a mirror 103 reciprocates in the direction of the arrow to illuminate the entire document P2. Then, the reflected light from the document P2 passes through the fixed mirror 105 and the lens system 106.
Therefore, it is guided onto the photosensitive drum 107 of the image forming section B, and an electrostatic latent image is formed thereon, and the electrostatic latent image is transferred to the sheet P1.

The sheet P1 on which the transfer has been performed is transported by a transport section D to a fixing section E, where it is subjected to a fixing process. Then, when the single-sided copy mode is set, the paper discharge section F closes the path to the automatic reversing and refeeding device (ADU) I by the path switching solenoid 108 and discharges the paper to the paper discharge tray G. On the other hand, when the double-sided copy mode is set, the paper discharge section F opens a path to the automatic reversing and refeeding unit (ADU) I by the path switching solenoid 108, and transfers the single-sided copied sheet P1 to the stacker introduction section. Send it to H. The single-sided copied sheet P1 sent to the stacker introduction section H is transferred to the automatic reversing and refeeding device (ADU) by the transport roller group 109.
)I is temporarily stacked on the intermediate tray 110. Then, the automatic reversing and refeeding device (ADU) I does not wait until all of the single-sided (front side) copied sheets P1 for the number of sheets set for double-sided copying are stacked on the intermediate tray 110; In the middle of this process, a feeding operation is started in order to re-feed the sheets P1 stacked on the intermediate tray 110 to the image forming section B via the intermediate conveyance section J. Then, copying is also performed on the back side in the image forming section B, and the sheet P1, which has been copied on both the front and back sides, is ejected to the paper ejection tray G via the conveyance section D, the fixing section E, and the paper ejection section F. .

The automatic reversing and refeeding device (ADU) I includes, in addition to the intermediate tray 110, a refeeding drive system, a feeding mechanism, a sorting mechanism, a stack sensor PS3, and a refeeding sensor P.
It has S4.

A paper refeeding drive system as shown in FIG. 2 is attached to the side surface of the casing of the automatic reversing and refeeding device (ADU) I, and the rotation of the ADU drive motor M is controlled by a gear 111.
, is transmitted to other gears via belt 112. In addition,
The arrow inside each gear indicates the rotation direction of the gear, the arrow on the belt 112 indicates the traveling direction of the belt, and the thick arrow indicates the conveying direction of the sheet P1. Further, the shafts of each gear pass through the inside of the housing and are pivotally supported on the opposite side surface of the housing, and various rollers, which will be described later, are pierced through these shafts. The rotation of the ADU motor M is decelerated by a reduction pulley 113 and transmitted to each gear. The gears 114a and 114b are
By rotating the rollers R1a and R1b in FIG. 1, the sheet P1 introduced from the stacker introduction section H is conveyed to the intermediate tray 110. In this situation, stack sensor PS1
Detected by. The rotation of the gear 115 is configured to be transmitted via the gear 116 to a gear 117 that rotates the delivery roller R2 in FIG. 1 and a gear 118 that rotates the conveyance roller R4 below the sorting roller R3 in FIG. However, a paper refeeding clutch 119 is also attached to the shaft of the gear 115, and only when the paper refeeding clutch 119 is turned on, the delivery roller R2 and the conveyance roller R4 are rotated. The gear 120 is the paper pressing body PR in FIG.
The paper pressing body PR will be explained in detail later.

The gear 121 transmits the rotation of the motor M to the sorting reduction gear 122, and the sorting reduction gear 122 decelerates the rotation of the motor M and transmits it to the sorting gear 124 via the belt 123. Then, the handling gear 124 is
The separating roller R3 is rotated in the opposite direction to the conveying roller R4 below it. The gears 125a and 125b rotate the transport rollers R5a and R5b shown in FIG. 1 to transport the sheet P1 sent out from the intermediate tray 110 and sorted. This conveyance status, that is, the paper refeeding status is detected by the paper refeeding sensor PS3. Further, the gears 126a and 126b rotate the conveyance rollers R6a and R6b shown in FIG. 1, which convey the sheet P1 that is then re-inverted. Note that the gear 127 is used to align the sheets by hitting the sheet P1 against the wall at the back (right side in FIG. 1) of the intermediate tray 110. Also, 12
8 to 131 are idlers. By collectively transmitting the rotation of the motor M to the various rollers via the belt and gears in this way, various operations can be easily synchronized and the number of drive sources is reduced.

FIG. 3 is a perspective view of the delivery mechanism. A delivery roller R2 is attached to the shaft 133 of the gear 117, and this delivery roller R2 rotates in the direction of the arrow to remove the sheets in the intermediate tray 110. Send out P1 one by one from the bottom in the direction of the thick arrow. In addition, the gear 120
Rollers 135 are attached to the shaft 134 at predetermined intervals, and rollers 137 are attached to the shaft 136 directly below the shaft 134 at positions corresponding to the rollers 135. The roller 135 and the roller 137 are connected by a belt 138, and the rotation of the gear 120 is transmitted to the roller 137. A paper pressing body PR is attached to the shaft 136 together with a roller 137, and when rotated as the roller 137 rotates, the shaft 136 presses the sheet P1 from above to assist the sheet feeding by the feeding roller R2. It is configured. Further, a wide rubber roller 139 attached to the shaft 134 is in contact with a roller 141 attached to the shaft 140 directly above it, and a one-turn clutch mechanism 142 is attached to the tip of the shaft 134. The shaft 14 is then rotated by the one-turn clutch mechanism 142.
By regulating the rotation of roller 141 and roller 13,
9, paper pressing body P via belt 138 and roller 137
The rotation of R is controlled.

FIG. 4 is an enlarged perspective view of the paper pressing member PR. The paper pushing member PR has a rotating member a and an arm member b. The rotating member a is fixed to the shaft 136, and the rotating member a and arm member b are hinged together by pin c,
Moreover, the rotating member a and the arm member b are biased by the wire-wound spring d so as to extend linearly. And shaft 1
36 (roller 137) rotates, the rotating member a and the arm member b rotate as one. This rotation is performed for the following reasons. That is, normally, in the initial state, the arm member b is located at the bottom of the intermediate tray 110, and the sheet P1 is stocked thereon, so that the arm member b is not pressing the sheet P1 from above. Therefore, in order to support sheet feeding by the feeding roller R2, the sheet P1 stacked on the intermediate tray 110 is rotated to press it. That is, the paper pressing body PR is brought into the following state by rotation. Assuming that the arm member b is in contact with the bottom of the intermediate tray 110 at the start of rotation, the sheet P1 is
As shown in (a), they are stacked on the arm member b. In this state, the stacked sheets P1 are not pressed from above and the frictional force with the delivery roller R2 is weak.
It is difficult to send out the sheet by the sending roller R2. Therefore, when the paper pressing body PR is rotated, the arm member b first moves away from the bottom of the intermediate tray 110 and retreats in the sheet feeding direction as shown in FIG. 5(b), and finally as shown in FIG. 5(c). As shown in , the arm member b comes above the intermediate tray 110 and presses the entire stacked sheet P1. In this state, sheet P1 and delivery roller R2
Since the frictional force between the feed roller R2 and the sheet P1 is strong, the feed roller R2 can easily feed the sheet P1. Such rotation of the paper pressing body PR is performed before the stacking is completed in order to re-feed the paper in the middle of stacking as described above.

FIG. 6 is a schematic diagram of the sorting mechanism. Since a plurality of sheets P1 may be stacked and sent out by the sending roller R2, the sorting mechanism separates them one by one in order to convey them one by one. That is, a sorting roller R3 is placed directly above the conveying roller R4 with a slight gap, and the conveying roller R4 takes over the sheet feeding operation by the feeding roller R2 and feeds the sheet P1, as shown by the arrow.
is rotated to convey it in its delivery direction. on the other hand,
The sorting roller R3 is rotated to move the sheet P1 in the opposite direction, thereby suppressing the conveyance of the upper sheet P1 and separating it one by one.The conveying roller R4 separates the sheet P1 into one sheet.
It operates so that sheets are conveyed one by one. In addition, the handling roller R3
A torque limiter 143 is connected to the delivery roller R.
2, the separating roller R3 is configured to rotate only when a plurality of sheets P1 are sent out in a stacked manner.

Next, an example of sheet conveyance operation in the double-sided copy mode will be described with reference to FIG. Note that this operation example is an example in which the number of sheets P1 to be double-sided copied is 10, and the numerical values in the figure are numbers for identifying each sheet P1.

As shown in FIG. 7, the paper feed motor of the paper feed device 300 and the ADU drive motor M of the copying machine main body 100 are operated after the duplex copy mode is set. , is started at the same time as the start switch is turned on. The paper feed clutch is turned on at predetermined time intervals according to the paper size, and a plurality of sheets P1 are continuously fed to the main body at predetermined intervals (see "Re"). This paper feeding status is detected by the paper feeding sensor PS4. Then, when the main body is transported to the position of the image forming section B by the transport section C within the main body, this is detected by the registration sensor PS5 (
(See “Le”). The sheet P1, which has been single-sided copied in the image forming section B, is conveyed to the paper discharge section F via the fixing section E. At this time, the path switching solenoid 108 of the paper discharge section F is turned on. ”), automatic reversing and refeeding device (AD
U) It is transported towards I. Then, the sheets are sequentially stacked on the intermediate tray 110 of the automatic reversing and refeeding unit (ADU) I via the stacker introducing section H. At this time, the first sheet P1 is at the bottom, and the next and subsequent sheets P1 are placed on top of it.
1 are stacked, but at this stage, the paper pressing body PR has not yet pressed the sheet P1. The number of sheets stacked on the intermediate tray 110 is detected by a stack sensor PS1 (see "T").

[0028] Then, in preparation for immediately moving to copying to the back side after the copying to the front side is completed, first, while the front side copying of the sixth sheet is being performed, that is, the stack sensor PS1 is When three sheets are detected to be stacked (see "R" and "TA"), the one-turn clutch 142 is turned on (see "Y"), and the intermediate tray 1 is moved by the paper pressing body PR.
The first to third sheets P1 in 10 are pressed and a timer is started. Then, when the timer turns off, the paper refeed clutch 119 is intermittently turned on (
1), an operation is started to feed out the single-sided copied sheets P1 in the intermediate tray 110 in order from the bottom. The sheet P1 sent out from the intermediate tray 110 is detected by the paper refeed sensor PS3 (see "R").

[0029] At the time when the third sheet is sent out from the intermediate tray 110, the fourth to seventh sheets in the intermediate tray 110 are
Since the third sheet P1 has not been pressed yet, the one-turn clutch 141 is activated at the same time as the third sheet is fed out from the intermediate tray 110 in order to press the fourth to seventh sheets in preparation for the next feeding. Turn on (see "Yo" and "R"). For the same reason, the 8th sheet was stacked afterwards~
In order to press the 10th sheet, the 1-turn clutch 141 is turned on at the same time as the 7th sheet is sent out from the intermediate tray 110 (see "Yo" and "R"). That is, the one-rotation clutch 141 is turned on from the second time onward every time four sheets are stacked. As a result, as is clear from Figure 7,
It is possible to transition from copying to the front side to copying to the back side at exactly the same interval as when copying to the front side.

In order to smoothly transition from copying on the front side to copying on the back side, as can be inferred from the above explanation, turning on the one-rotation clutch 142 for the first time based on the timer and re-supplying the clutch 142 are necessary. How to control the start timing of intermittent ON of the paper clutch 119, that is,
The important point is how to start and stop the timer. Therefore, the start timing and stop timing of the timer will be explained.

[0031] The start timing of the timer is determined according to the difference between the transport time between the automatic paper feeder 300 and the register sensor PS5 and the transport time between the intermediate tray 110 and the register sensor PS5. In other words, the longer it takes to transport between the automatic paper feeder 300 and the register sensor PS5 than the transport between the intermediate tray 110 and the register sensor PS5, the earlier the timer start timing becomes, and the earlier the front side of the previous sheet is A timer must be started when copying.

[0032] Also, the stop timing of the timer is
It is determined according to the time required for reversing the document by the automatic document feeder 200. If the time required for reversing the original is shorter than the sheet transport time interval during continuous copying, the time interval between the last sheet of front-side copying and the first sheet of back-side copying is also the same as the next sheet transporting time interval during normal continuous copying. be able to.

In short, the time limit for the first pressing operation of the one-rotation clutch 141 for smoothly transitioning to reverse side copying is determined by the time limit for the first pressing operation of the single-rotation clutch 141 when a predetermined number of sheets P1 from the last sheet are pressed, depending on the specifications of the apparatus such as the above-mentioned various conveyance times. Uniquely determined to be the stack point.

Next, another example of sheet conveyance operation in the double-sided copy mode will be described with reference to FIG. In addition,
This operation example is an example in which there are seven sheets P1 to be double-sided copied, but since there are many operations in common with the above example, only the different points will be briefly explained.

When the number of sheets P1 to be double-sided copied is as small as 7, at the timing when the first sheet P1 that has been copied on one side is stacked on the intermediate tray 110, the resist sensor PS5 detects the third uncopied sheet from the end. The sheet P1 to be processed is detected, and if paper is not pressed at this timing, the transition from copying on the front side to copying on the back side will not be performed smoothly. Therefore, the first sheet P1, which has been copied on one side, is transferred to the stack sensor PS1.
When detected, the one-turn clutch 142 is immediately turned on. Then, the one-turn clutch 142 is turned off, and the one-turn clutch 142 is turned off.
At the same time as the pressing operation for the first sheet P1 is completed, the paper refeeding clutch 119 is intermittently turned on to start a paper refeeding operation that sequentially feeds out the single-sided copied sheets P1 in the intermediate tray 110 from the bottom. do.

At this time, in order to re-feed the second and subsequent single-sided copied sheets P1 while being pressed by the paper pressing member PR, the second and subsequent single-sided copied sheets P1 are
When detected by the stack sensor PS1, the one-turn clutch 142 is turned on each time. In other words, when there are few sheets P1 to be double-sided copied, the one-turn clutch 142 is turned on every time the first sheet P1 that has been copied on one side is stacked on the intermediate tray 110, and the sheet P1 is
1 is re-fed while being pressed one by one. Note that if the number of sheets set for continuous copying is slightly more than 7, the paper refeeding operation will not be started immediately after the first press, but a timer will be set up as in the case of Fig. 7. The paper refeeding operation may be started some time after the first press.

In this way, by starting the paper refeeding operation while the sheets that have been copied are being stacked on the intermediate tray 110, the front surface is You can move from copying to back side copying, etc. In other words, in order to perform double-sided printing or multiplex printing, when performing another printing process on multiple sheets that have been continuously printed once again, the paper feeding operation for the reprinting process can be quickly performed. It is possible to migrate and speed up the migration.

[0038]

Effects of the Invention As explained above, according to the sheet feeding device of the present invention, when a plurality of sheets that have been subjected to continuous recording processing are again successively subjected to other recording processing, it is possible to It is possible to quickly shift to the paper feeding operation for re-recording processing, and it is possible to speed up double-sided recording and multiplex recording.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram of an electrophotographic copying machine equipped with a sheet feeding device according to the present invention.

FIG. 2 is a configuration diagram of a paper refeeding drive system of an automatic reversing paper refeeding device in the main body of the electrophotographic copying machine in FIG. 1;

FIG. 3 is a configuration diagram of a delivery mechanism of the automatic reversing and refeeding device.

FIG. 4 is an enlarged perspective view of a paper pressing member.

FIGS. 5A, 5B, and 5C are diagrams for step-by-step explanation of rotation of a paper pressing member.

FIG. 6 is a schematic diagram of a sorting mechanism of the automatic reversing and refeeding device.

FIG. 7 is a time chart of an example of sheet conveyance operation.

FIG. 8 is a time chart of another example of sheet conveyance operation.

[Explanation of symbols]

I Automatic reversing paper refeeding device B Image forming section PR Paper pressing body P1 sheet PS1 Stack sensor R2 Delivery roller 110 Intermediate tray 142 1 rotation clutch M　ADU drive motor

Claims (3)

[Claims] Claim 1: A plurality of sheets of paper that have undergone recording processing are stacked on a stacking means in order to continuously perform recording processing on the plurality of sheets of paper that have undergone recording processing from the stacking means. A sheet feeding device that sequentially feeds the sheets to the stacking means, a feeding device that sequentially feeds the sheets of paper from the stacking means by contacting the lowest sheet of paper stacked on the stacking means; When the number of sheets of paper set as continuous recording target is less than or equal to a predetermined number, each time a sheet of paper is stacked on the stacking means, Paper pressing control means for activating and pressing the pressing means; and feeding control means for starting the feeding means and starting the feeding operation of the sheet of paper after the sheet of paper is pressed by the control of the paper pressing control means. A sheet feeding device characterized by comprising: 2. The sheet feeding device according to claim 1, wherein the paper pressing control means activates the paper pressing means by detecting a stacking state of sheet-shaped paper on the stacking means. . 3. The sheet feeding device according to claim 1, wherein the predetermined number of sheets is 1 or more and 8 or less.