JPH06161184A - Automatic double-side copying machine - Google Patents

Abstract

PURPOSE:To obtain high feeding reliability with overlap feed hardly generated at an intermediate tray part with a common inlet-outlet and obtain rapid switch- back action so as to allow the rotation of a carrier roller to be switched in a short time. CONSTITUTION:A paper separating clutch 45b and a delivery clutch 45d are fitted to the end part of a shaft inserted through the feed side roller 30a of a paper separating roller. Driving force is obtained from a drive motor 45e rotated in one direction, and the rotating direction is switched by the alternate interruption of a stacking clutch 45n and a paper refeeding clutch 45o. At the stacking time, the stacking clutch 45n and the paper separating clutch 45b are connected, and the refeeding clutch 45o is disconnected so as to rotate a carrier roller 34 and the feed side roller 30a in the lead-in direction. At the paper refeeding time, the stacking clutch 45n is disconnected, and the refeeding clutch 45o and the paper separating clutch 45b are connected.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic double-sided copying machine for recording images on both sides of a sheet of recording paper, and more particularly to an automatic double-sided copying machine having a common entrance / exit of an intermediate tray portion of the recording paper.

[0002]

2. Description of the Related Art A conventional automatic double-sided copying machine records an image on one side of a recording sheet in an image forming section, and then carries this recording sheet into a reverse conveying path of a double-sided recording sheet conveying unit (ADU). A system in which stock sheets are once stocked in an intermediate tray section called a stacker and then recording sheets are sent again to the image forming section through a re-feeding conveyance path has been adopted, but in order to miniaturize the apparatus, for example, Japanese Patent Laid-Open No. Hei 3 There has been proposed an automatic double-sided copying machine having a common entrance / exit of an intermediate tray as described in Japanese Patent Laid-Open No. 227886.

In the case of an intermediate tray section having a common entrance / exit, a conveying roller rotating in forward and reverse directions and a separating roller for preventing double feeding at the time of re-feeding are necessary, but in the conventional automatic double-sided copying machine. The carrying roller and the separating roller are used as a pair of rollers facing each other. That is, the separating roller has a one-way clutch built therein so that the separating roller rotates together with the conveying roller at the time of introduction, but does not rotate at the time of re-feeding to perform the separating operation. The transport roller also serves as a delivery roller, and at the time of re-feeding, the paper is pressed into contact with the recording paper to be sent out, and at the same time, a judgment operation is performed at a contact point with the judgment roller.

There is also a system in which the delivery roller and the separating roller are separately provided, but a one-way clutch is usually incorporated in the separating roller to prevent the accompanying rotation of the separating roller from being transmitted to the delivering roller. However, if the one-way clutch is engaged in this way, the transport roller cannot rotate in the forward and reverse directions.

In such forward / reverse driving of the conveying roller, the rotation direction of the motor is directly switched. Further, in order to convey the fed recording paper at high speed, an electromagnetic clutch is provided on the feeding roller, and the feeding roller is controlled to be free when the recording paper is fed by a predetermined length.

[0006]

However, if the sending roller and the carrying roller are used in combination, even if the trailing edge of the first sheet is sent out from the pressing portion of the roller of the sending section, the nipping with the separating roller is still achieved. Since the first recording sheet exists in the section, the delivery roller itself continues to rotate as the recording sheet is conveyed, and the conveyance force is applied to the second sheet that is in pressure contact with the delivery roller. Therefore, it has a drawback that double feeding is easy.

Further, in the conventional automatic double-sided copying machine in which the rotation direction of the conveying roller is switched by changing the rotation of the drive motor, it takes time for the rise and fall of the rotation of the drive motor, which makes it impossible to reverse the switchback at a high speed. Therefore, increasing the current value, heat generation, motor durability, power supply capacity, etc. have become problems when trying to shorten the time.

The present invention solves the above-mentioned drawbacks of the conventional automatic double-sided copying machine, realizes a re-feeding mechanism in the intermediate tray portion common to the entrance and exit, which makes it difficult to double feed, and improves the feeding reliability. The purpose is to Another object of the present invention is to provide an automatic double-sided copying machine capable of switching the rotation direction of the conveying rollers in a short time because the switchback in the intermediate tray portion is performed at high speed.

[0009]

In order to solve the above-mentioned problems, according to the invention of claim 1, the image forming section records an image on one side of a recording sheet fed from a sheet feeding section, and then it is also used for introduction and discharge. An intermediate tray portion for accommodating and stacking the recording sheets via a conveyance path, a feeding roller for re-feeding the recording sheets from the intermediate tray portion, and a pair of separating rollers for preventing double feeding at the time of re-feeding, In an automatic double-sided copying machine having a rotational force transmission mechanism for rotating the feed side roller of the separation roller in the forward and reverse directions and rotating the delivery roller in the sheet re-feeding direction, the rotational force transmission mechanism includes a transmission side of the separation roller. The present invention is characterized by having a separating clutch for intermittently rotating the roller and a delivery clutch for intermittently rotating the delivery roller.

Further, the automatic double-sided copying machine according to claim 2 is
An intermediate tray part for storing and loading the recording paper on one side of the recording paper fed from the paper feeding part in the image forming part after the image forming part, and the intermediate tray part for storing the recording paper. In an automatic double-sided copying machine equipped with a transport roller capable of forward and reverse stacking and re-feeding from the intermediate tray section, a drive motor for driving the transport roller in one direction and power of the drive motor It is characterized in that it has two clutches that are transmitted to and a conveyance control unit that selectively connects and disconnects the two clutches to switch the rotation direction of the conveyance roller.

According to another aspect of the present invention, in the automatic double-sided copying machine, after recording an image on one side of a recording sheet fed from the sheet feeding section by the image forming section, the recording sheet is stored and loaded through the introduction / ejecting / conveying path. In an automatic double-sided copying machine that includes an intermediate tray unit that performs forward and reverse rotation, and that stacks the recording sheets on the intermediate tray unit and re-feeds the sheets from the intermediate tray unit, the transport roller rotates in one direction. Two pulleys that rotate in the same direction in conjunction with the drive motor, a stack clutch provided on one shaft of these two pulleys, a re-feeding clutch provided on the other shaft, and this re-feeding A re-feeding gear connected to the clutch, a stack gear connected to the stack clutch and meshing with the re-feeding gear, and the conveying roller meshing with one of the stack gear and the re-feeding gear. A transfer gear for rotation in forward and reverse directions, is characterized by having a transfer control means for selectively intermittently the stack clutch and the refeed clutch.

[0012]

According to the first aspect of the invention, the image is recorded on one side of the recording sheet fed from the sheet feeding section by the image forming section, and then the recording sheet is introduced into the intermediate tray section via the introduction / ejecting and conveying path. When the recording sheet is re-fed from the intermediate tray section, the feeding roller is rotated and fed to the separating roller. The feed side rollers of the separating roller rotate in the forward and reverse directions, but the pair of separating sides stop at the time of re-feeding, thus preventing double feeding. Since the feeding roller of the sorting roller is provided with a sorting clutch, and the feeding roller also has a feeding clutch, the feeding roller is prevented from being fed when the sheet is re-fed.

During stacking, the separating clutch of the feed side roller is connected to rotate in the stack direction, and during discharging, the separating clutch and the sending clutch are connected to rotate both in the re-feeding direction. When the recording paper is sent to the introduction / discharge delivery path, both the separating clutch and the sending clutch are disengaged, and the separating roller and the sending roller are freed.

According to the second aspect of the invention, the recording paper is introduced and discharged by changing the rotation direction of the conveying roller, but the driving force is a drive motor that rotates in one direction. This drive motor rotates in the same direction, but is controlled by the conveyance control means so as to selectively connect and disconnect the two clutches to connect only one of them, thereby switching the rotation direction of the conveyance roller. As described above, since the rotation of the transport roller is switched only by switching the clutch, it is not necessary to rotate the drive motor in the forward and reverse directions.

In the automatic double-sided copying machine according to the third aspect of the invention, the recording paper is introduced and discharged by changing the rotation direction of the conveying roller, and the driving force is a drive motor which rotates in one direction.
The two pulleys that rotate in the same direction in conjunction with the drive motor always rotate in the same direction, but only one of the stack clutch and the re-feeding clutch provided on each shaft is connected by the conveyance control means. Controlled to do so. That is, when the re-feeding clutch is connected, the re-feeding gear on this shaft rotates and the free stack gear rotates. At the same time, since the transport gear meshing with one of the stack gear and the re-feeding gear is also rotated, the transport roller can be rotated in the re-feeding direction.

On the contrary, when the stack clutch is connected and the re-feeding clutch is disengaged, the stack gear connected to the stack clutch is rotated and the re-feeding gear which is free is rotated. The transport gear is rotated in the stack direction in conjunction with these. As described above, since the rotation of the transport roller is switched only by switching the clutch, it is not necessary to rotate the drive motor in the forward and reverse directions.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT An embodiment of an automatic double-sided copying machine according to the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic configuration diagram of an automatic double-sided copying machine.

The automatic double-sided copying machine 1 has a main body portion 2 and a paper feed unit portion 3 connected to the main body portion 2, and a plurality of paper feed stages 4 are provided in each of them, and a sheet-like recording paper 5 is provided in each.
To house. A paper feed roller 6 is arranged on the upper surface of the recording paper 5 of each paper feed stage 4, and the recording paper 5 is delivered intermittently. A double-feeding prevention unit 7 is provided in parallel with each of the paper feed rollers 6 and sends out the recording papers 5 one by one to the next step.
The recording papers 5 sent out from the respective paper feed stages 4 are guided to the guide plates 8 respectively, and the second paper feed unit 9 built in the main body 2 is provided.
Be delivered to. The second paper feeding unit 9 is arranged immediately before the image forming unit 100, and has a loop roller 10 and a registration roller 11.

On the other hand, in the photoconductor 12 constituting the image forming section 100, uniform charging is applied by the charging electrode 13, and the reflected light obtained by irradiating the original 16 on the original placing glass 15 by the light source 14 is obtained. Is irradiated onto the peripheral surface of the photoconductor 12 as an image carrier via the mirror 17 and the lens mechanism 18 to form an electrostatic latent image. The original 16 is placed at a predetermined position via an automatic original feeding device (RADF) 101 with a double-sided original automatic reversing function provided on the original placing glass 15 so as to be openable and closable.

The electrostatic latent image on the photoconductor 12 is the developing unit 1
9 is developed to form a toner image. The registration roller 11 is driven in synchronism with the rotation of the photoconductor 12, and the recording paper 5
Is sent to the transfer electrode 20 and the separation electrode 21 to transfer the toner image. After that, the recording paper 5 is separated from the photoconductor 12 by the separation claw 22, placed on the conveyance unit 23, and conveyed to the fixing unit 24 in the next step. Further, the cleaning unit 2 is provided on the downstream side of the separation claw 22 around the photoconductor 12.
5, the surface of the photoconductor 12 after the transfer is cleaned, and is charged again by the charging electrode 13 for the next image formation.

The recording paper 5 heated and pressurized in the fixing unit 24 fixes the toner image, and when it is ejected out of the machine, the conveying roller 26 and the switching gate which constitute the reversal ejection switching means 102 according to the copy mode. When the recording paper is fed to the transport roller 29 through the switching gate 27 and the straight sheet discharge mode after passing through 27, the sheet is discharged to the bin of the sorter 103 outside the machine through the sheet discharge roller 28, the transport roller 29 is rotated in the reverse direction. Then, the recording paper is switched back to perform either operation of the reverse paper ejection mode in which the recording paper is ejected through the paper ejection roller 28. The reversal sheet discharge switching means 102 sorts the feeding path of the recording sheet 5 to the sorter 103 side or the intermediate tray sheet feeding unit 104 side by operating a selection button on an operation panel (not shown). When performing double-sided copying, the sheet enters the intermediate tray sheet feeding unit 104 while being sandwiched by the transport roller 29 of the reversing transport path 105 via the transport roller 26 and the switching gate 27.

Next, the structure of the intermediate tray paper feeding unit 104 will be described with reference to FIGS. 2 is a vertical sectional view of the intermediate sheet feeding unit 104, and FIG. 3 is a schematic plan view of the same. The intermediate tray paper feeding unit 104 is called a double-sided recording paper transporting unit (ADU), and as shown in FIG. 2, the recording paper introducing / discharging means 30, the intermediate tray 31, and the recording to be stored and loaded on the intermediate tray 31. It has a re-feeding unit 32 for re-feeding the sheet 5 and a re-feeding conveyance path 33 arranged below the intermediate tray 31. The upstream portion from the branch point of the re-feeding conveyance path 33 and the reversing conveyance path 105 is
The conveyance path 33a for both introduction and discharge is formed.

As shown in FIG. 3, the recording paper introducing / discharging means 30 has a feed side roller (lower roller) 30a which can be driven in the forward / reverse direction at substantially the center of the introduction / delivery conveying path 33a, and the feed side roller 30a. A one-way clutch or a reverse roller (upper roller) 30b with a built-in torque limiter is provided, which is pressed to rotate when driven into the recording paper, but reversely or stopped when the recording paper is discharged. The pair of upper and lower rollers 30a and 30b form a separating roller 130. or,
Introducing and discharging conveyance path 3 sandwiching the separation roller 130
A plurality of stack auxiliary rollers 30c are arranged on the upper surface of 3a. The stack auxiliary roller 30c is rotatably attached to the other end of a mounting plate 30e whose one end is fixed to the rotary shaft 30d, and is lowered when the recording paper 5 is introduced by the rotation of the rotary shaft 30d. It contacts the lower roller 30f which opposes. Therefore, the recording paper 5 to be introduced is stably conveyed while being pressed. Further, at the time of discharging, it is separated from the lower roller 30f to release the pressure bonding. The rotating shaft 30d is the lifting means 3
5 to the Geneva gear mechanism 43.

A pair of conveying rollers 34, which rotate in the forward and reverse directions, are provided at the central portion of the conveying path 33a also serving as the introducing / discharging conveying path adjacent to the recording sheet introducing / discharging means 30. A sensor 42 for detecting the recording paper 5 sent to the recording paper introducing / discharging means 30 is arranged on the reverse conveyance path 105 side of the conveying roller 34.

When the recording sheet 5 is carried in from the reversing conveying path 105, both the conveying roller 34 and the feed side roller 30a rotate in the introducing direction, and at this time, the upper roller 30b is driven to rotate. When the recording paper 5 is discharged, the upper roller 30b reverses or stops, so that double feeding is prevented, and the separated recording paper 5 is nipped by the conveying roller 34 rotating in the discharging direction and sent out to the introduction / discharge conveying path 33a. In order not to hinder the separation work by the upper roller 30b, the stack auxiliary roller 30c releases the pressure.

The re-feeding conveying path 33 is the reversing conveying path 10.
When separated from the branch point with 5, the intermediate tray paper feeding unit 1
It is connected to the loop roller 10 of the second sheet feeding section 9 through the outer periphery of 04. The re-fed recording paper 5 forms an image on the back surface thereof, passes through the reverse paper ejection switching unit 102, passes through the paper ejection roller 28, and is ejected onto the bin of the sorter 103 outside the apparatus.

Inside the intermediate tray 31, a stack tray 36 which can be moved up and down by the action of the elevating means 35 is arranged. The stack tray 36 is in a lowered state when the recording paper 5 is introduced, and is raised when the recording paper 5 is stored and stacked again to come into pressure contact with a load plate 37 arranged above the recording paper 5. Further, the sheet re-feeding means 3 is provided at the front of the stack tray 36.
A bottom feeding roller 38, which is included in No. 2, is arranged, and when the stack tray 36 rises, the recording sheet 5 is sandwiched between the load plate 37 and pressed to be fed out from the bottom portion and fed to the recording sheet introducing / discharging means 30. At this time, since the leading end of the recording paper 5 is separated by the upper roller 30b, only the lowermost recording paper 5 is re-fed.

The bottom feeding roller 38 is attached to the opening 36a of the stack tray 36 and moves up and down integrally with the stack tray 36. Side plates 37a are attached to both sides of the load plate 37, and the stack auxiliary rollers 30c are attached to the end portions of the side plates 37a.
The rotating shaft 30d for holding is inserted. The load plate 37 is rotatable around the rotating shaft 30d. Also the rotating shaft 3
A load plate operating shaft 37b is projected from the side plate 37a in parallel with 0d and is connected to the Geneva gear mechanism 43 of the elevating means 35. By these mechanisms, the load plate 37 retracts from the transport path when the recording sheet 5 is introduced, and moves to a position where the recording sheet 5 is pressed when the recording sheet 5 is discharged.

Inside the intermediate tray 31, there are provided a leading edge paper aligning stopper 39 that moves according to the size of the recording sheet 5 and stops the leading edge of the sheet, and a movable width regulating plate 40 that similarly regulates the side surface of the sheet. It is provided. The respective drive devices arranged in the intermediate tray paper feed unit 104 are driven under the control of the conveyance control means 106 built in the main body 2.

The intermediate tray paper feeding unit 104 is provided with slide rails 41 on both side surfaces of the unit main body so that it can be pulled out from the main body 2. When a paper jam occurs in the recording paper introducing / discharging means 30 or the re-feeding conveyance path 33, the paper jam can be pulled out to easily inspect and correct and restart the paper feeding.

The elevating means 35 secures the support member 35a for abutting the rotatable roller to the lower surface of the stack tray 36, the arm member 35b for connecting the support member 35a to one end, and the other end of the arm member 35b. It has a rotating shaft 35c and a Geneva gear mechanism 43 for intermittently rotating the rotating shaft 35c. A plurality of supporting members 35a are arranged on the lower surface of the stack tray 36, and stably hold the stack tray 5 on which the recording sheets 5 are stacked when the stack tray 5 is raised.

In the Geneva gear mechanism 43, a drive source thereof is a DC motor 43a capable of adjusting a rotation speed, and its rotation is transmitted to a worm wheel 43c and a disc 43d fixed to the worm wheel 43c via a worm 43b. DC motor 43
A is connected to the conveyance control means 106 to perform forward / reverse rotation and speed adjustment. Pin 43e protruding from the worm wheel 43c
The Geneva gear 43f that engages with and rotates intermittently has a rotating shaft 35c fixed to the center thereof and moves the support member 35a up and down. Since the Geneva gear 43f has a fixed stop position and the rotation at the time of stop is suppressed, a heavy object can be stably held. Therefore, the height of the stack tray 36 becomes stable. The Geneva gear mechanism 43 of the elevating means 35 is also connected to the rotating shaft 30d of the stack auxiliary roller 30c and the load plate operating shaft 37b, and operates according to their respective purposes.

Next, the feed side roller 3 of the separating roller 130
0a and the rotational force transmission mechanism of the conveying roller 34 and the bottom feeding roller 38 will be described. The upstream side 4 of the rotational force transmission mechanism 45 is provided at one end of the shaft 30n for fixing the feed side roller 30a.
A separating clutch 45b forming a part of 5a is attached, and a delivery clutch 45d forming a part of a downstream side 45c of the rotational force transmitting mechanism 45 is attached to the other end of the shaft 30n.

The structure of the upstream side 45a of the rotational force transmission mechanism 45 will be described with reference to FIGS. FIG. 4 is a view on arrow A in FIG. The driving force of the rotational force transmission mechanism 45 is obtained from the driving motor 45e that rotates in one direction. Drive motor 4
The rotational force of 5e is transmitted to the timing pulley 45h via the timing pulley 45f and the timing belt 45g, and is transmitted to the timing pulley 45i coaxially connected to the timing pulley 45h. Timing pulley 45i
The timing belt 45j stretched over the two belts rotates two timing pulleys 45k and 45m in the same direction. An electromagnetic stack clutch 45n is coaxially attached to one of these timing pulleys 45k, and the other timing pulley 45m is similarly re-feed clutch 45n.
o is attached. Further, a stack gear 45p is attached to the stack clutch 45n, and a sheet re-feed gear 45q is attached to the sheet re-feed clutch 45o, which mesh with each other.
Further, the re-feeding gear 45q rotates the separating gear 45s via the conveying gear 45r. A separating clutch 45b is provided on the rear surface of the separating gear 45s, and
A drive-side transport roller 34 is mounted coaxially with r.

Stack clutch 45n, refeeding clutch 45o, sorting clutch 45b, and delivery clutch 45c.
Are intermittently controlled by the transport control means 106. When stacking, connect the stack clutch 45n,
The re-feeding clutch 45o is disengaged, and the judgment clutch 45b is connected. At this time, the stack gear 45p rotates in the direction of the solid line arrow in FIG. 4, and the transport gear 45r rotates in the recording paper introducing direction via the re-feeding gear 45q in the free state. In addition,
The upper side of the transport roller 34 is the driving side. The sorting gear 45s also rotates in the direction of the solid arrow, and the sorting clutch 45b
The feed-side roller 30a of the separating roller 130 is rotated in the recording paper introducing direction via the.

At the time of re-feeding, the stack clutch 45n is disengaged, and the re-feeding clutch 45o and the separating clutch 45b are connected. At this time, the re-feeding gear 45o rotates in the direction of the one-dot chain line arrow in FIG. 4, and the transport gear 45r and the separating gear 45s rotate in the recording paper discharge direction (the direction of the one-dot chain line arrow). Therefore, the feed side roller 30a is connected via the judgment clutch 45b.
Also rotates in the recording paper ejection direction. As described above, the rotation switching of the transport roller 34 and the feed side roller 30a is performed by switching between the stack clutch 45n and the sheet re-feeding clutch 45o, so that it is not necessary to rotate the drive motor 45e forward and backward, and high-speed rotation switching is possible. Become.

Next, the structure of the downstream side 45c of the rotational force transmission mechanism 45 will be described with reference to FIGS. FIG. 5 shows B of FIG.
FIG. A gear 46 is attached to the outer side of a delivery clutch 45d attached to a shaft 30n that passes through the feed side roller 30a of the separation roller 130, and is fixed to an end of the rotary shaft 38a of the bottom delivery roller 38 via an idle gear 47. The delivery gear 48 is rotated. The delivery gear 48 moves up and down along with the stack tray 36, and the idle gear 47 also moves while meshing with it, thereby connecting the gear 46 and the delivery gear 48. FIG. 5 shows the stacking state, and the delivery clutch 45d is in the disengaged state.
Therefore, the delivery roller 38 does not rotate.

At the time of re-feeding, as shown in FIG.
5 to raise the stack tray 36 and the recording paper 5,
The upper surface of the recording paper 5 is pressed against the load plate 37. When the delivery clutch 45d is connected in this state, the separation clutch 45
The shaft 3 of the feed side roller 30a that is connected to b and is rotating
Upon receiving the rotation of 0n, the gear 46, the idle gear 47, and the delivery gear 48 rotate in the direction of the one-dot chain line arrow shown in FIG.
Therefore, the delivery roller 38 also rotates in the recording paper discharge direction.

When one sheet of recording paper 5 separated by the upper roller 30b of the separating roller 130 and separated is detected by the sensor 42 through the conveying roller 34 and the leading end portion thereof is detected by the sensor 42.
Sends a detection signal to the conveyance control means 106, thereby disconnecting both the separating clutch 45b and the sending clutch 45d. For this reason, the feeding side roller 30a of the separating roller 130 is free, but the connection portion to the bottom feeding roller 38 is also cut off. Therefore, even if the feeding side roller 30a rotates with the discharged recording paper 5, the bottom feeding roller 30a is fed. The roller 38 does not rotate.

[0040]

As described above, in the automatic double-sided copying machine according to the first aspect of the present invention, since the rotating force transmitting mechanism is provided with both the separating clutch and the supplying clutch, the supplying roller which does not rotate with the rotation of the separating roller is used. It is possible to provide an automatic double-sided copying machine having a high feeding reliability by realizing a re-feeding mechanism in the intermediate tray part common to the entrance and exit, which makes it difficult to double feed.

The automatic double-sided copying machine according to claim 2 is
Although the drive motor rotates in the same direction, the transport control means controls to selectively connect and disconnect the two clutches to connect only one of them, and the rotation direction of the transport roller is switched. Therefore, the rotation of the transport roller is switched. It is only necessary to switch the clutch, and it is not necessary to rotate the drive motor in the forward and reverse directions, and it is possible to introduce and discharge the recording paper by changing the rotation direction of the conveying roller.

The automatic double-sided copying machine according to claim 3 is
Since the stack clutch and the sheet re-feeding clutch that are alternately turned on and off are provided, the rotation direction of the transport roller can be switched without rotating the drive motor forward and backward, and the rotation can be switched at high speed. Therefore, high-speed switchback can be performed in the intermediate tray portion, and the processing time can be shortened. Also, by using the separating clutch, the sending clutch, the stack clutch, and the re-feeding clutch as electromagnetic clutches, it is possible to facilitate high-speed connection and disconnection.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram of an automatic double-sided copying machine.

FIG. 2 is a vertical sectional view of an intermediate sheet feeding unit.

FIG. 3 is a schematic plan view of an intermediate paper feeding unit.

FIG. 4 is a view on arrow A in FIG.

5 is a view from the direction of the arrow B in FIG. 3 at the time of stacking.

FIG. 6 is a view in the direction of arrow B in FIG. 3 at the time of re-feeding.

[Explanation of symbols]

 1 Automatic Double-sided Copying Machine 5 Recording Paper 30a Feeding Side Roller 30b Upper Roller 31 Intermediate Tray 34 Conveying Roller 38 Bottom Feeding Roller 45 Rotational Force Transmission Mechanism 45b Saw Clutch 45d Feeding Clutch 45e Drive Motor 45n Stack Clutch 45o Refeed Clutch 45p Stack Gear 45q Re-feeding gear 45r Conveying gear 45s Separation gear 48 Sending gear 130 Separation roller

 ─────────────────────────────────────────────────── ─── Continuation of front page (72) Inventor Makoto Tamura 482-6 Yatsugasaki, Matsudo City, Chiba Prefecture (72) Inventor Michihiko Kanbara 123-32 Obuchi, Fujino-cho, Tsukui-gun, Kanagawa Prefecture

Claims (3)

[Claims] 1. An intermediate tray unit for storing and stacking the recording paper, which has been image-recorded on one side of the recording paper fed from the paper feeding unit by an image forming unit, and then is stored and loaded through a conveyance path for both introduction and discharge, and this intermediate tray. A feed roller for re-feeding the recording paper from the unit, and a pair of separating rollers for preventing double feed during re-feeding,
In an automatic double-sided copying machine having a rotational force transmission mechanism for rotating the feed side roller of the separation roller in the forward and reverse directions and rotating the delivery roller in the sheet re-feeding direction, the rotational force transmission mechanism includes a transmission side of the separation roller. An automatic double-sided copying machine, comprising: a separating clutch for intermittently rotating the rotation of a roller; and a delivery clutch for intermittently rotating the rotation of the delivery roller. 2. An intermediate tray section for storing and stacking the recording sheet after the image is recorded on one side of the recording sheet fed from the sheet feeding section by the image forming section, and the recording sheet is also loaded and conveyed through the conveyance path for both introduction and discharge. In the automatic double-sided copying machine having a forward / reverse transport roller for stacking sheets of paper on the intermediate tray portion and re-feeding paper from the intermediate tray portion, a drive motor that drives the transport roller and rotates in one direction; Two clutches that transmit the power of
An automatic double-sided copying machine, comprising: a conveyance control unit that selectively connects and disconnects individual clutches to switch the rotation direction of the conveyance rollers. 3. An intermediate tray section for storing and stacking the recording sheet after the image is recorded on one surface of the recording sheet fed from the sheet feeding section by the image forming section, and the recording sheet. In an automatic double-sided copying machine having a forward / reverse transport roller for stacking sheets of paper on the intermediate tray section and re-feeding paper from the intermediate tray section, the transport rollers are in the same direction in conjunction with a drive motor that rotates in one direction. Two pulleys that rotate in parallel, a stack clutch provided on one shaft of these two pulleys, a refeed clutch provided on the other shaft, and a refeed gear connected to this refeed clutch. A stack gear that is connected to the stack clutch and meshes with the re-feeding gear, and a transport gear that meshes with one of the stack gear or the re-feeding gear and that rotates the transport roller in forward and reverse directions, An automatic double-sided copying machine comprising: a conveyance control unit that selectively connects and disconnects the stack clutch and the re-feeding clutch.