JP2003182909A - Sheet direction switching device, and sheet discharging device and sheet treatment device using same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To switch in at least three directions in a space-saving manner. <P>SOLUTION: In this sheet direction switching device 3 provided in the middle of a sheet carrying passage 2 in a treatment device body 1 to switch the sheet carrying direction into three directions, branch-carrying passages 5 branching into three ways (more specifically, 5a to 5c) are provided on a branched part 4 of the sheet carrying passage 2, two gate members 6 (more specifically, 6a and 6b) are disposed on the branched part 4, and two gate members 6 (6a and 6b) are cooperated so that any one of the three branch-carrying passages 5 (5a-5c) is switch-selectable. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet direction switching device used in a sheet processing apparatus including an image forming apparatus such as a copying machine or a printer, and more particularly to accommodating a discharged sheet capable of switching in at least three directions. The present invention relates to a sheet discharging device intended to easily change the possible number of sheets and a sheet processing apparatus using the same.

[0002]

2. Description of the Related Art Generally, a sheet processing apparatus including an image forming apparatus such as a copying machine or a printer is provided with a plurality of branched conveyance paths on a sheet conveyance path, and a sheet direction switching device is installed at the branch point. The direction switching device is configured to switch and convey the sheet to a plurality of branch conveying paths. This type of sheet direction switching device employs a system (two-way switching system) that normally switches the sheet transport direction between two directions (see, for example, Japanese Patent Laid-Open No. 10-305955). For example, in a sheet discharging device assembled in an image forming apparatus as a sheet processing device, there are face-down discharging for discharging a sheet with an image surface facing down and face-up discharging for discharging a sheet with a face image surface facing upward. Two-way switching such as switching, face-down discharge to a normal discharge tray and discharge to another option discharge unit, and further switching between normal face-down discharge and conveyance to a double-sided recording unit Usually done.

[0003]

However, this type of sheet direction switching device cannot perform switching in a plurality of directions exceeding two directions. For this reason, for example, in order to switch the sheet transport direction to three directions, a two-way switching system is adopted at two positions of the sheet transport path, so that a sequential branching system is adopted. The sheet conveyance path length for increasing itself occurs, and for example, when it is difficult to secure the sheet conveyance path length for branching,
A technical problem arises in that it cannot be branched in three directions.

The present invention has been made to solve the above technical problems, and is a space-saving sheet direction switching device capable of switching in at least three directions, and a sheet discharging device using the same. A sheet processing apparatus is provided.

[0005]

That is, according to the present invention, as shown in FIG. 1, the sheet direction switching is provided in the middle of the sheet transporting path 2 in the processing apparatus main body 1 to switch the sheet transporting direction to three directions. In the apparatus 3, the branch conveyance path 5 (specifically, 5a
.About.5c), two gate members 6 (specifically, 6a and 6b) are provided in the branching portion 4, and any one of the branching conveyance paths 5 (5a to 5c) can be switched and selected. It is characterized in that the two gate members 6 (6a, 6b) work together so that

In such technical means, the present invention is mainly directed to a mode in which the sheet conveying direction is switched to three directions. However, the present invention can be applied to switching of four or more directions, and in this case, it is provided in the middle of the sheet transport path 2 in the processing apparatus main body 1 to switch the sheet transport direction to three or more directions. Seat direction switching device 3
In addition, a branch conveyance path 5 (5a, 5b, 5c ...) that branches into three or more is provided in the branch section 4 of the sheet conveyance path 2, and the branch section 4 has two branch conveyance paths less than five. The gate members 6 (6a, 6b ...) As described above are arranged, and the gate members 6 (6a, 6b ...) Cooperate so that any one of the branch conveyance paths 5 can be switched and selected. Good. Here, arranging two or more gate members 6 that are less than the number of branch conveyance paths 5 excludes a mode in which the gate members 6 are individually arranged in the branch conveyance paths 5.

Further, in the present case, the sheet direction switching device 3 is intended for a device provided at an arbitrary position of the sheet conveying path 2. Further, although the branching portion 4 basically shows a portion having three branching conveying paths 5, the branching portion 4 is not limited to the embodiment having one branching point. Here, the requirement that the branch portion has three branch conveyance paths 5 excludes a mode in which two branch paths sequentially branch. Furthermore, although it is limited to the mode in which the three branch conveyance paths 5 are provided, the three branch conveyance paths 5 can be provided even if there is another conveyance path communicating with the three branch conveyance paths 5. There is no difference in that.

The two gate members 6 (6a, 6b)
Is necessary for switching and selecting the three branch conveying paths 5 (5a to 5c), and a mode in which the three branch conveying paths are switched and selected by three gate members is excluded. Further, cooperating the two gate members 6 means operating the two gate members 6, respectively. However, for example, in the case where the gate member in the fixed state is formally added (formally three gate members), the gate member in the fixed state is not the gate member of the present case, so The embodiment substantially corresponds to two gate members.

Further, as a typical embodiment of the present invention, 1
A mode in which one branch point is provided with three branch transport paths, or a mode in which two branch points are provided with three branch transport paths can be mentioned. Here, the former mode is, for example, as shown in FIG.
As shown in (A), three branch conveyance paths 5 (5a-5
c) is branched into three branches with one branch point P as a center, and two gate members 6 (6a, 6b) are arranged to face each other with the middle branch conveyance path 5b interposed therebetween.
As shown in (A), two gate members (6a, 6b)
By switching between the solid line position and the virtual line position,
The respective branch conveyance paths 5 (5a to 5c) are switched and conveyed.

On the other hand, in the latter mode, as shown in FIG. 2 (B), three branch conveyance paths 5 (5a to 5c) are provided with two branch points P1 and P2 which are moved back and forth in the sheet conveyance direction. The gate members 6 (6a, 6b) are arranged at the branch points P1, P2, and as shown in FIG. 2B, the two gate members (6a, 6b) are switched between a solid line position and a virtual line position. By operating, each branch conveyance path 5 (5a-5c) is switched and conveyed.

Further, as a typical application target of the sheet direction switching device 3, as shown in FIG. 1, there is a sheet discharging device 7. In this case, in the sheet discharging device 7 disposed near the exit of the sheet conveying path 2 in the processing device body 1, the sheet discharging device 7 may be provided with the above-described sheet direction switching device 3. The sheet discharging device 7 may be fixedly provided to the processing device main body 1 or detachably provided.

Further, as a preferable function of the sheet discharging device 7, a sheet discharging device 7 having a fixing device 8 on the upstream side of the sheet discharging device 3 of the sheet conveying path 2 of the processing apparatus main body 1 is provided.
2A and 2B, at least one of the branch conveyance paths 5 extends in a direction in which the curl of the sheet generated when passing through the fixing device 8 can be corrected (in this example, 5).
b is equivalent). According to this aspect, it is preferable in that the curl of the sheet can be corrected without providing a curl correcting device.

Further, as a typical function of the sheet discharging device, the branch conveying path 5 has a face-down discharging path (for example, 5a) for discharging an image downward and a face-up discharging path for discharging an image upward. A mode in which a discharge path (for example, 5b) is provided to enable face-up and face-down discharge is preferable. Furthermore, three branch conveyance paths 5 (5a-5
It is possible to provide a reverse branch conveyance path in c). In this case, at least one of the three branch conveyance paths 5 (5a) is provided with a reverse branch conveyance path communicating with the opposite side, and the one branch conveyance path 5 (5a) is switched under the condition selected. It suffices that the sheet conveyed to the branch conveyance path 5 (5a) can be reversely conveyed toward the reverse branch conveyance path. As a typical example of this aspect, which will be described in detail in the embodiments, for example, in a sheet processing apparatus including a double-sided recording unit, there is a case where a sheet is returned to the double-sided recording unit.

Further, as a mode of switching and discharging the sheet in three directions, a mode in which the option unit 13 is added to the sheet discharging device 7 can be mentioned. In this case, by using the added option unit 13,
Large capacity sheets can be discharged and offset sheets can be discharged for each job. In this aspect, the sheet ejection device 7
In, it is preferable that the option unit 13 can be detachably held.

Further, the present invention is not limited to the sheet direction switching device 3 and the sheet discharging device 7, but may be a sheet processing device having the sheet direction switching device 3 or a sheet processing device having the sheet discharging device 7. Also target. At this time, when the image forming apparatus is used as the sheet processing apparatus, it is necessary to incorporate the image forming engine 11 and the sheet feeding apparatus 12.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described below in detail based on the embodiments shown in the accompanying drawings. First Embodiment FIG. 3 is an explanatory diagram showing the overall configuration of the first embodiment of the sheet processing apparatus (image forming apparatus in this example) to which the present invention is applied. In the figure, the image forming apparatus has an image forming engine 21 mounted in a main body housing 20, and a predetermined number (three-stage configuration in this example) of sheet feeding devices 22 to 24 (below the image forming engine 21). In the present example, the lowermost sheet feeding device 24 is arranged externally, and a discharging tray 25 for storing discharged sheets is arranged above the main body housing 20. The sheet conveying path 26 extending in a substantially vertical direction from 24 to 24 toward the discharge tray 25 is provided.

In the present embodiment, the image forming engine 21
For example, an electrophotographic type is adopted, and the photoconductor drum 31, a charging device (for example, a charging roll) 32 that charges the photoconductor drum 31, and the photoconductor drum 3 are used.
An optical unit (for example, a laser scanning device) 33 that writes a latent image on the photosensitive drum 1 with a light beam, and a developing device 34 that visualizes the latent image on the photosensitive drum 31 with toner as a developer.
A transfer device (for example, a transfer roll) 35 that transfers a visible image (toner image) on the photosensitive drum 31 to a sheet, and a cleaning device (for example, a blade cleaning device) 36 that cleans residual toner on the photosensitive drum 31. It has and. Further, in this embodiment, the photosensitive drum 31, the charging device 32, the developing device 34, and the cleaning device 36 are integrated as one process cartridge, and are configured to be detachable from the main body housing 20.
In this example, the developing device 34 has a detachable toner cartridge 34a.

Further, in the present embodiment, each of the sheet feeding devices 22 to 24 has a pickup roll 41 for taking out and conveying the sheet and a separating roll (for example, a feed roll and a retard roll) for separating the taken out sheets one by one. Combination) 42. Furthermore, an appropriate number of transport rolls 43 are provided in the sheet transport path 26, and a registration roll 44 for positioning the sheet is provided immediately upstream of the transfer portion of the photoconductor drum 31, while the photoconductor is provided. A fixing device 50 is arranged downstream of the transfer portion of the drum 31.

Further, in the present embodiment, a sheet discharging device 60 is arranged at the exit portion of the sheet conveying path 26, and the sheet discharging device 60 is provided in the main body housing 20.
A sheet discharge unit 61 that is detachable with respect to is provided. In the present embodiment, this sheet discharge unit 6
As shown in FIGS. 3 and 4, 1 has branch discharge paths 71 to 73 branched in three directions in the unit main body 70, and the first branch discharge path 71 is used as a discharge tray on the upper part of the main body housing 20. 25, the second branch discharge path 72 is extended toward the side opposite to the first branch discharge path 71, and the third branch transport path 73 is the first and second branch transport paths. It extends substantially upward in the middle of 71 and 72, and a face-up tray 62 is arranged outside the outlet of the second branch discharge passage 72, while another is provided above the third branch discharge passage 73. The optional discharge unit 63 is disposed. In this example, an offset catch tray (OCT: Abbreviation of Offset Catch Tray) that offset-discharges sheets is used as the option discharge unit 63. The option discharge unit 63 includes a sheet discharge path 64 and a transport roll. 65, discharge roll 66
Also, a tray member 67 is provided.

Further, a double-sided recording unit 80 is attached to the main body housing 20, and the double-sided recording unit 80 discharges a single-sided recorded sheet when the double-sided mode for recording images on both sides of the sheet is selected. The sheet is taken in from the apparatus 60 side, and the sheet is conveyed along the internal sheet return conveyance path 81 by an appropriate number of conveyance rolls 82 and is supplied again to the registration roll 44 side.

Further, in the present embodiment, the sheet conveying path 2
6, sensors 91 to 93, 95 for detecting the sheet position are provided in the sheet return conveyance path 82 and the sheet discharge path 76. In this example, the sensor 91 is the sheet conveying path 2
A registration sensor and a sensor 92, which are provided immediately before the upstream side of the registration roll 44 of FIG. 6 and where the sheet return conveyance path 81 joins, are provided immediately before the upstream side of the sheet discharge unit 61 of the sheet conveyance path 26. A discharge sensor used for discharge control, and a sensor 93 are position sensors provided in the sheet return conveyance path 82 and used for double-sided recording conveyance control of the sheet.
Reference numeral 95 denotes an ejection sensor provided in the sheet ejection path 64 and used for sheet ejection control.

In particular, in this embodiment, the sheet discharge unit 61 has a unit receiving portion 100 on the upper portion of the main body housing 20 as shown in FIGS. 4 to 6, and is detachable from the unit receiving portion 100. Attached to. In this case, as shown in FIG. 6, for example, the mounting structure of the sheet discharging unit 61 is such that the unit main body 70 side is provided with the positioning pin 111 as the engaged portion, the locking projection 112, and the screw receiving concave portion 113 while the unit receiving portion is provided. The part 100 is provided with a positioning hole 101, a locking hole 102, and a screwing piece 103 as an engaging part that can engage with the engaged part.
The engaged parts 111 to 113 are engaged with 103, and are fixed by screws (not shown) in a state of positioning and locking. In the present embodiment, the part 70 a of the unit main body 70 is the opening / closing door 1 of the main body housing 20.
It is detachably attached to 05. Also, in the figure, 11
Reference numeral 5 denotes an outer cover of the sheet discharge unit 60.

Here, in the present embodiment, as shown in FIGS. 4 and 5, the sheet discharge unit 61 is located on the upstream side of the branch point P of the three branch discharge paths 71 to 73 branched in the unit main body 70. Has a sheet carrying-in path 74 extending downward on the fixing device 50 side, and a double-sided recording conveying path 75 which extends substantially linearly on the opposite side of the first branching / discharging path 71 with the branch point P interposed therebetween. The sheet return transport path 81 of the unit 80 is connected for communication. Further, paired discharge rolls 121 and 122 are disposed near the outlets of the first and second branch discharge paths 71 and 72, and two discharge rolls 121 and 122 are provided near the branch points of the branch conveyance paths 71 to 73. The switching gates 131 and 132 are arranged opposite to each other with the third branch discharge path 73 interposed therebetween.

In the present embodiment, the discharge roll 12
Reference numerals 1 and 122 are configured to cause the drive discharge roll 123 and the driven discharge roll 124 to roll in contact with each other. The first switching gate 131 is composed of a substantially triangular gate member, and both sides of the gate member extending toward the branch point P side of the gate member are configured as guide surfaces 133 and 134, and are indicated by solid lines (first position). Branch discharge path 73
Is closed between the second switching gate 132 and the guide surface 133.
Along a guide surface 134 between a position where the sheet is guided to the first branch discharge path 71 along the line and a position indicated by an imaginary line (the first branch conveyance path 71 is blocked and the second switching gate 132 is provided). And the position where the sheet is guided to the third branch discharge path 73).

On the other hand, the second switching gate 132 is also made of a substantially triangular gate member, and both sides of the gate member extending to the branch point P side of the gate member are connected to the guide surfaces 135 and 13.
6 and the position indicated by the solid line (the second branch discharge path 72 is closed, and the sheet is guided to the third branch discharge path 71 along the guide surface 136 between the first switching gate 131 and the position. Position) and a position indicated by an imaginary line (the third branch conveyance path 73 is closed between the first switching gate 131 and the guide surface 1).
A position for guiding the sheet to the second branch discharge path 72 along the position 35) is swingably switched.

Further, FIG. 7 shows a drive transmission system of the sheet discharging device used in the present embodiment. In the figure, a drive transmission system 140 is configured to transmit the driving force from a drive motor 141 capable of rotating in the forward and reverse directions via a transmission gear 142 to the first discharge roll 1.
21 to the driven gear 144 provided coaxially with the drive discharge roll 123, and via the transmission gear 143 to the driven gear 145 provided coaxially with the drive discharge roll 123 of the second discharge roll 122. Is also adapted to transmit drive.

Further, in the present embodiment, the fixing device 50
Is equipped with a heat fixing roll 51 having a built-in heat source and a pressure fixing roll 52 that rolls in contact with the heat fixing roll 51 at a predetermined nip pressure. This fixing device 50 has a separate drive transmission system. It is adapted to rotate at 53.
That is, in the present embodiment, the drive transmission system 53 includes a driven gear 57 provided coaxially with the heat fixing roll 51 via a gear train 56 for forming a predetermined reduction ratio of the driving force from the drive motor 54. The driving force from the driving motor 54 is engaged with the heating fixing roller 51 to be transmitted.

Further, the drive transmission system 140 is connected to the switching gates 131 and 13 via electromagnetic solenoids 147 and 148.
The switching operation of 2 is performed. The drive motor 141 and the electromagnetic solenoids 147, 148 of the drive transmission system 140 are driven and controlled according to control signals from the control device 149 according to an image forming control program (including a sheet ejection control program). It has become.
The control device 149 receives detection signals from the sensors 91 to 93, 95 and the like and is used to generate the control signal.

Next, the operation of the image forming apparatus according to this embodiment will be described. As shown in FIG. 3, in the image forming engine 21, a predetermined toner image is formed on the photosensitive drum 31, while the sheet is supplied to the sheet conveying path 26 from any of the sheet supplying devices 22 to 24. The toner image on the photoconductor drum 31 is transferred onto a sheet by the transfer device 35. Then, the transferred sheet is subjected to a fixing process by the fixing device 50, and then is passed through the sheet discharge device 60 to a predetermined position. It is discharged to the discharge site. The residual toner on the photosensitive drum 31 is cleaned by the cleaning device 36 to prepare for the next image forming cycle.

In such an image forming process, paying attention to the sheet discharge device 60, the sheet discharge control is performed in accordance with various sheet discharge modes as described below. Face-down discharge mode This is a mode in which the sheet S is discharged to the discharge tray 25 side with its image side facing down. At this time, the two switching gates 131 and 132 perform a switching operation as shown in FIG. 8A, closing the second and third branch discharge paths 72 and 73, and
The branch discharge path 71 is opened, the sheet S is guided and conveyed along the guide surface 133 of the first switching gate 131, and the first discharge roll 121 is driven to rotate normally to convey the sheet S by nip (FIG. 5). reference).

Face-Up Discharge Mode This is a mode in which the sheet S is discharged to the face-up tray 62 side with its image surface facing up. At this time, 2
The two switching gates 131 and 132 perform switching operations as shown in FIG. 8B, block the first and third branch discharge paths 71 and 73, open the second branch discharge path 72, and open the second branch discharge path 72. The sheet S is guided and conveyed along the guide surface 135 of the switching gate 132, and the second discharge roll 122 is driven to rotate normally to convey the sheet S by nip (see FIG. 5). In particular, when the face-up discharge mode is executed, the curl is formed on the sheet S in a predetermined direction when passing through the fixing device 50, but the second branch discharge path 72 is directed to correct the curl of the sheet S. Because of the extension, the curl of the sheet S is naturally corrected without the need for a separate device for curl correction.

OCT discharge mode This is a mode in which the sheet S is discharged to the OCT side which is the optional discharge unit 63. At this time, the two switching gates 131 and 132 perform a switching operation as shown in FIG. 8C to close the first and second branch discharge paths 71 and 72,
The third branch discharge path 73 is opened, and the sheet S is guided and conveyed along the guide surfaces 134 and 136 of the first and second switching gates 131 and 132 (see FIG. 5).

Sheet reversal control in double-sided recording mode This is sheet conveyance control when returning the sheet S, which has been recorded on one side to the double-sided recording unit 80, in the double-sided recording mode. At this time, the two switching gates 131 and 132 perform a switching operation as shown in FIG. 8D, and guide and convey the sheet S on which one side has been recorded toward the first branch discharge path 71 side. After the discharge roll 121 is driven to rotate in the normal direction to convey the sheet S by a predetermined amount, when the sheet S exceeds the branch point P, the normal rotation drive of the first discharge roll 121 is switched to the reverse rotation drive. The sheet S held in the nip by the discharge roll 121 is conveyed in the opposite direction through the first branch discharge path 71, and the double-sided recording conveyance path that communicates with the first branch discharge path 71 in a substantially linear manner. It is guided and conveyed to the side of 75 and is conveyed to the double-sided recording unit 80 (see FIG. 5). Both discharge rolls 121 and 122 and both switching gates 131 and 1
The operation timing of 32 is controlled based on the detection signal of the discharge sensor 92.

Further, in the present embodiment, if the facing surfaces of the two switching gates 131 and 132 are formed in a comb-teeth shape so as to be fitted to each other, for example, the face-down discharge mode to the face-up discharge mode. 8B, only the second switching gate 132 is held from the imaginary line position to the solid line position as shown in FIG. 8B while the first switching gate 131 is held at the same position (solid line position in FIG. 8A). All you have to do is switch to the position. According to such an aspect,
The switching control of the switching gates 131 and 132 can be performed more easily.

Replacement of Sheet Ejection Unit Further, in the present embodiment, the sheet ejection unit 61 is
Since it is detachable from the unit receiving portion 100 of the main body housing 20, the sheet discharging unit 61 used in the present embodiment has a configuration capable of discharging a sheet in three directions, but can discharge in two directions. The sheet discharge unit 150 can be replaced with various types of sheet discharge units 150, such as a configuration, a configuration that allows discharge in only one direction, or a variable sheet discharge position depending on the number of sheets that can be discharged. For example, as shown in FIGS. 9 and 10, a sheet ejection unit 150 for ejecting a sheet in only one direction is used.

The sheet discharge unit 150 is provided with, for example, a discharge passage 155 extending in a predetermined direction in the unit main body 151, and the drive discharge roll 15 is provided in a part of the discharge passage 155.
3 and a discharge roll 152 including a driven discharge roll 154
Is provided. The sheet discharge unit 150 does not include, for example, its own drive source, and the transmission gear 58 is engaged with a part of the drive transmission system 53 of the fixing device 50, and the drive discharge roll 153 is attached to the transmission gear 58. A driven gear 59 provided coaxially with the gear meshes with each other to transmit the driving force. Further, the sheet discharging unit 150 includes the engaging portions 101 to 10 on the unit receiving portion 100 side.
3 has engaging portions 156 to 158 to be engaged and disengaged, and the sheet discharge unit 150 of another specification can be easily replaced in place of the sheet discharge unit 61.

In this way, the sheet discharge units 61, 15
Even if 0 is replaced, since the discharge sensor 92 is provided on the main body housing 20 side, the position of the discharge sensor 92 does not change even if the sheet discharge unit 150 of another specification is assembled. A control method similar to that before replacement is adopted.

Second Embodiment FIG. 11 shows a main part of a second embodiment of an image forming apparatus to which the present invention is applied. In the figure, the basic configuration of the image forming apparatus is substantially the same as that of the first embodiment, but the first embodiment is the same.
Unlike the first embodiment, the configuration of the double-sided recording unit 80 and the configuration of the sheet discharge unit 60 are different from those of the first embodiment. The same components as those of the first embodiment are similar to those of the first embodiment.
The same reference numerals are given and detailed description thereof is omitted here. In the present embodiment, the double-sided recording unit 80 is arranged facing the side portion of the sheet discharge unit 60, and is for double-sided recording located on the downstream side of the second branch discharge path 72 of the sheet discharge unit 61. In the sheet return conveyance path 81 of the unit 80, a branch discharge path 84 is provided via a switching gate 83.
Is provided, and a discharge roll 85 is provided at the exit portion of the branch discharge path 84, and the branch discharge path 84 communicates with the face-up tray 62 side.

The sheet discharge unit 61 is shown in FIG.
Further, as shown in FIG. 12, three branch discharge passages 71 to 7 branched in the unit main body 70 are substantially similar to the first embodiment.
However, unlike the first embodiment, the first branch point P1 is branched into the second branch discharge path 72 and the other branch point, and the second branch point P2 is divided into the first and the second branch discharge paths 72. Branch discharge path 3
1, 73 are branched, and a sheet carry-in path 74 extending downward on the fixing device 50 side is provided on the upstream side of the first branch point P1, and a first branch discharge path 71 and a second branch discharge path 72 are provided. The communication transport path 76 is configured to communicate with each other substantially linearly. In addition, the first and second branch discharge paths 71, 72
A pair of discharge rolls 161 and 162 are disposed near the outlet of the switch, and switching gates 171 and 172 are further provided near the respective branch points P1 and P2.

In the present embodiment, the discharge roll 16
1 and 162 are configured so as to cause the drive discharge roll 163 and the driven discharge roll 164 to roll in contact with each other, and are drive-controlled in substantially the same manner as in the first embodiment, but unlike the first embodiment, The second discharge roll 162 is driven to rotate in the normal direction while the first discharge roll 161 is driven to rotate in the reverse direction. Further, the first switching gate 171 is formed of a substantially triangular gate member, and both sides of the gate member extending toward the branch point P1 side of the gate member are provided with guide surfaces 173.
174, and the other side is configured as a third guide surface 177, and the position shown by the solid line (second branch discharge path 7
2 where the sheet is closed and the sheet is guided along the guide surface 173 to the joint flow path side of the first and third branch discharge paths 71, 73).
Positions indicated by imaginary lines (first and third branch discharge paths 71, 73
(The position for guiding the sheet to the second branch discharge path 72 along the guide surface 174 of the first switching gate 171) is swung freely for switching operation. .

On the other hand, the second switching gate 172 is also made up of a substantially triangular gate member, and both sides of the gate member extending toward the branch point P2 side of this gate member are guided by guide surfaces 175,1.
And a position indicated by a solid line (a position for closing the third branch discharge path 73 and guiding the sheet to the first branch discharge path 71 along the guide surface 175 of the second switching gate 172). , A position indicated by a virtual line (the first branch conveyance path 71
And a position where the sheet is guided to the third branch discharge path 73 along the guide surface 176 of the second switching gate 172).

Next, the operation of the image forming apparatus according to this embodiment will be described. In the present embodiment, the image forming process is performed in substantially the same manner as in the first embodiment. In such an image forming process, paying attention to the sheet discharge device 60, the sheet discharge control is performed according to various sheet discharge modes described below, for example. Face-down discharge mode This is a mode in which the sheet S is discharged to the discharge tray 25 side with its image side facing down. At this time, the two gates 171 and 172 perform switching operation as shown in FIG. 13A, the first switching gate 171 closes the second branch discharge path 72, and the second switching gate 172 moves to the third gate. Branch discharge path 73
And the first branch discharge path 71 is opened, the sheet S is guided and conveyed along the guide surface 175 of the second switching gate 172, and the first discharge roll 161 is driven to rotate in the normal direction to move the sheet S. The nip is conveyed (see FIG. 12).

Face-up discharge mode This is a mode in which the sheet S is discharged to the face-up tray 62 side with its image surface facing up. At this time, 2
The two switching gates 171 and 172 perform switching operation as shown in FIG. 13B, the first switching gate 171 blocks the second and third branch discharge paths 72 and 73, and the second branch discharge path 7
2 is opened, the sheet S is guided and conveyed along the guide surface 174 of the first switching gate 171, and the second discharge roll 162 is conveyed.
Rotates in the forward direction to convey the sheet S by nip (see FIG. 12). At this time, the state of the second switching gate 172 may be arbitrarily set regardless of the solid line position or the virtual line position. As shown in FIG. 11, the sheet S discharged from the second branch discharge path 72 reaches the sheet return conveyance path 81, passes through the branch discharge path 84, and is discharged to the face-up tray 62 through the discharge roll 85.

OCT discharge mode This is a mode in which the sheet S is discharged to the OCT side which is the optional discharge unit 63. At this time, the two switching gates 171 and 172 perform a switching operation as shown in FIG. 13C, and the first switching gate 171 closes the second branch discharge passage 72, so that the second switching gate 172 is operated. The first branch discharge path 71 and the third branch discharge path 73 are opened to guide the sheet S along the guide surface 173 of the first switching gate 171 and the guide surface 176 of the second switching gate 172. Transport (see FIG. 12).

Sheet reversal control in double-sided recording mode This is sheet conveyance control when the sheet S, which has been single-sided recorded, is returned to the double-sided recording unit 80 in the double-sided recording mode. At this time, the two switching gates 171 and 172 perform a switching operation as shown in FIG. 13D, and guide and convey the sheet S on which one side has been recorded toward the first branch discharge path 71 side.
After the first discharge roll 161 is driven to rotate in the normal direction to convey the sheet S by a predetermined amount, the sheet S is conveyed to the second branch point P2.
When it exceeds the value, the forward rotation driving of the first discharge roll 161 is switched to the reverse rotation drive, and the sheet S held in the nip by the first discharge roll 161 is conveyed in the reverse direction through the first branch discharge passage 71. Then, the guide surface 174 of the second switching gate 172 and the third guide surface 1 of the first switching gate 171.
Along 77, it is guided and conveyed to the side of the communication conveyance path 76 that communicates with the first branch discharge path 71 in a substantially linear manner, and is conveyed to the double-sided recording unit 80 by the normal rotation drive of the second discharge roll 162. (See Figure 12). After that, the sheet S discharged from the second branch discharge path 72 is, as shown in FIG.
After passing through the sheet return / conveyance path 81, the double-sided recording unit 80 reaches the registration roll 44 again in the inverted state, and is subjected to the image forming process by the image forming engine 21.

[0046]

As described above, according to the present invention, at least three branching conveyance paths are provided at the branching portion, two gate members are arranged at the branching portion, and at least one of the branching members is provided. Since the branch conveyance path is switched and selected, it is possible to save space and switch in at least three directions. Further, in a sheet discharging device and a sheet processing device using such a sheet direction switching device,
Since the sheets can be switched in at least three directions in a space-saving manner, the sheet switching and discharging operation and the sheet switching and conveying operation can be realized more efficiently.

[Brief description of drawings]

FIG. 1 is an explanatory diagram showing an outline of a sheet direction switching device, a sheet discharging device and a sheet processing device using the same according to the present invention.

FIG. 2A is an explanatory view showing one aspect of the seat direction switching device according to the present invention, and FIG. 2B is an explanatory diagram showing another aspect of the seat direction switching device.

FIG. 3 is an explanatory diagram showing the first embodiment of the sheet processing apparatus to which the present invention is applied.

FIG. 4 is an enlarged view of a main part of FIG.

FIG. 5 is an explanatory diagram showing details of a sheet discharging device used in the present embodiment.

FIG. 6 is a perspective view of a main part of a sheet discharge unit used in the present embodiment.

FIG. 7 is an explanatory diagram showing a drive transmission system of the sheet ejection device according to the present embodiment.

8A to 8D are explanatory views showing a sheet direction switching state of the sheet discharging device according to the present embodiment.

FIG. 9 is an explanatory diagram showing a state in which another sheet discharge unit is attached in the present embodiment.

FIG. 10 is a perspective view of a main part showing details of the sheet discharge unit of FIG.

FIG. 11 is a principal part explanatory view showing a second embodiment of the sheet processing apparatus to which the present invention is applied.

FIG. 12 is an explanatory diagram showing details of the sheet ejection device used in the present embodiment.

13A to 13D are explanatory views showing a sheet direction switching state of the sheet discharging device according to the present embodiment.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Processing device main body, 2 ... Sheet conveyance path, 3 ... Unit receiving part, 4 (4a, 4b) ... Sheet discharge unit, 5 ... Sensor, 6 ... Fixing device, 11 ... Image forming engine, 12 ... Sheet feeding device

Claims (11)

[Claims] 1. A sheet direction switching device provided in the middle of a sheet transport path in a main body of a processing apparatus for switching a sheet transport direction to three directions, and a branch transport for branching into three at a branch portion of the sheet transport path. A path is provided, and two gate members are provided at this branching portion, and one of the branching and transporting paths can be switched and selected.
A seat direction switching device characterized in that two gate members work together. 2. The sheet direction switching device according to claim 1, wherein the three branch conveyance paths are trifurcated around one branch point, and the two gate members are sandwiched by the middle branch conveyance path. A seat direction switching device, which is arranged opposite to each other. 3. The sheet direction switching device according to claim 1, wherein the three branch conveying paths are provided with two branch points which are located in front of and behind each other in the sheet conveying direction, and the gate member is arranged at each of the two branch points. Seat direction switching device. 4. A sheet discharging device arranged near an exit of a sheet conveying path in a main body of a processing device, wherein the sheet discharging device is equipped with the sheet direction switching device according to any one of claims 1 to 3. A sheet discharging device. 5. The sheet discharging device according to claim 4, wherein a fixing device is provided on the upstream side of the sheet discharging device of the sheet conveying path of the main body of the processing device, wherein at least one of the branch conveying paths is for a sheet generated when passing through the fixing device. A sheet discharge device, which is a discharge path extending in a direction in which curl can be corrected. 6. The sheet discharging apparatus according to claim 4, wherein the branch conveying path includes a face-down discharging path for discharging the image downward and a face-up discharging path for discharging the image upward. A sheet ejection device characterized in that 7. The sheet discharging apparatus according to claim 4, wherein at least one of the three branch conveyance paths is provided with a reverse branch conveyance path communicating with the opposite side, and the one branch conveyance path is selected for switching. A sheet discharging device, which is capable of reversely transporting a sheet transported to the branch transport path under the conditions toward the reverse branch transport path. 8. The sheet discharging apparatus according to claim 4, wherein the option unit can be detachably held. 9. A sheet processing apparatus comprising the sheet direction switching device according to claim 1 in the middle of a sheet conveying path of a processing apparatus main body. 10. A sheet processing apparatus provided with the sheet discharging apparatus according to claim 4. 11. A sheet direction switching device, which is provided in the middle of a sheet transporting path in a main body of a processing apparatus and switches a sheet transporting direction to three or more directions. A branch conveyance path is provided, and two or more gate members, which are smaller than the number of branch conveyance paths, are provided at this branch portion, and each gate member is shared so that any one of the branch conveyance paths can be switched and selected. A seat direction switching device characterized by being operated.