JP3182395B2 - Paper feeder - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to an electrostatographic copying machine,
The present invention relates to a sheet feeding device provided in an image forming apparatus such as a printer and a facsimile, and more particularly to a sheet feeding device suitable for use in producing a large number of identical double-sided images.

[0002]

2. Description of the Related Art As the above-mentioned paper feeding device, a switchback path is provided in the middle of a paper carrying path from an image forming section to an intermediate tray, and sheets after one-sided image formation are sequentially switched back, and are temporarily stored in the intermediate tray. Based on the refeed information for image formation on the other side, the paper stocked in the intermediate tray is turned over, and the paper is re-fed back to the image forming unit. is there.

According to the sheet feeding apparatus having the above-described configuration, compared with a sheet feeding apparatus which repeatedly forms an A image on the front surface of a sheet and a B image (hereinafter, referred to as a double-sided image) on the back surface. Since the sheets on which the single-sided image is formed are sequentially and temporarily stored in the intermediate tray, a large number of sheets on which the same double-sided image is formed can be efficiently obtained in time.

However, in the paper feeder having such a configuration, after the sheet on which single-sided image formation has been completed is completely discharged from the switchback path, the next image formation sheet must be introduced into the switchback path. Therefore, the stock time was long for the time required to switch back the paper.

Therefore, the present inventors temporarily stock the sheets on the intermediate tray without switching back the sheets after the single-sided image formation, and sequentially turn the stock sheets upside down based on the re-feeding information to change the image. By causing the forming unit to re-feed, a large number of sheets with the same two-sided image formed
In addition, we developed a paper feeder that can be obtained efficiently in terms of time.

The specific structure of this paper feeder is as follows. That is, a transport roller that is driven in reverse rotation based on refeed information and a carry-in roller that feeds image forming paper to the intermediate tray by using the transport roller are disposed in the middle of a paper carry-in path extending from the paper introduction unit to the intermediate tray. And a paper carry-out path for re-feeding the sheets stored in the intermediate tray to the image forming unit is arranged at an upper portion of the intermediate tray. The apparatus includes sheet lifting means for pressing a sheet against the transport roller, a double feed prevention roller abutting on the transport roller, and path switching means for bypassing the sheet reverse to the sheet input path to the sheet output path.

According to the paper feeder having the above configuration, the stock time of the paper can be reduced by the time required to switch back the paper after the single-sided image is formed. The transport roller that feeds the intermediate tray is driven in reverse rotation based on the refeed information, and this transport roller also serves as the feed roller.In addition, the carry-in roller comes into contact with the transport roller. The double feed prevention roller is kept in contact with the transport roller based on the re-feed information to prevent double feed of paper.

[0008]

In the paper feeding apparatus having such a configuration, when a paper jam occurs in the paper carry-in path when stock is supplied to the intermediate tray, the apparatus main body constituting the paper carry-in path The other path component is moved in the path opening direction with respect to the side path component, and the jammed sheet is pulled out through the gap.

The double feed prevention roller is separated from the transport roller until it receives the refeed information, so there is no problem. However, since the carry-in roller is always in contact with the transport roller, both rollers are in contact. When forcibly pulling out the paper nipped, the paper may be torn.

Further, if a jam occurs during re-feeding of the stock paper, the double feed prevention roller is separated from the transport roller based on the detection of the jam, so that there is no problem. The paper is torn at the nip point when jamming re-feeded paper, and the path switching means is in the way, so that the jammed paper can be pulled out. There was also a problem in terms of difficulty.

SUMMARY OF THE INVENTION The present invention has been made in view of the above-mentioned circumstances, and a paper feeder capable of easily performing a jam processing without tearing of paper by simple and rational improvement. It is intended to provide.

[0012]

In order to solve the above-mentioned problems, the present invention relates to the above-mentioned paper feeder, wherein the stock time for switching back the paper can be reduced. According to the invention, the other path component is provided so as to be movable in the path opening direction with respect to the path component on the apparatus main body side that forms the paper carrying path, and the carrying in of the path is performed with the path opening movement of the path component. It is characterized in that the rollers are separated from the transport rollers.

In addition to the above, according to the second aspect of the present invention, the other detour path provided with the path switching means is provided for the detour path constituent member on the apparatus main body side of the detour path formed by the transport roller and the path switching means. It is characterized in that the constituent members are provided so as to be movable in the path opening direction.

According to the first aspect of the invention, when a paper jam occurs in the paper carry-in path at the time of paper supply to the intermediate tray, the other path constituting member is routed to pull out the jammed paper. When the paper is moved in the opening direction, the carry-in roller is moved away from the transport roller in conjunction with this, and the nip of the paper by the two rollers is released, so that the jammed paper can be pulled out without causing the paper to tear. Easy to do.

According to the second aspect of the present invention, if a jam occurs during refeeding of the stock paper, the above-described jam processing mode is taken, that is, the other path constituting member is moved in the path opening direction. When the other detour path component is moved in the path opening direction in a state where the nip of the sheet by the transport roller and the carry-in roller is released by moving the path roller, the path switching unit that hinders the sheet withdrawal is caused. By separating from the transport roller, the jamming of the re-feed paper can be easily and easily performed without causing the paper to tear.

[0016]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a printer (an example of an image forming apparatus) mounted on a sheet feeding unit 1. The printer includes an image forming unit 3 having an image forming drum 2.
Then, a sheet of a predetermined size is conveyed to the image forming unit of the image forming unit 3 from the image forming information output unit 4 for the unit 3 and the plurality of upper and lower sheet cassettes 6 provided in the sheet cassette 5 or the sheet feeding unit 1. Paper feed path 7
A paper feed path 9 for conveying the sheet after image formation to the fixing device 8, a sheet discharge path 11 for discharging the sheet after fixing to the sheet discharge tray 10 at the top of the apparatus, and a large number of double-sided images are created in the same manner. Paper feeder 12 suitable for use in
2 and a path switching means 13 for switching and feeding paper to the paper discharge path 11.

As shown in FIGS. 2 to 4, the sheet feeding device 12 is provided with an intermediate tray 14 for temporarily stocking a sheet on which a single-sided image is formed, which can be swung up and down around a support shaft 15, as shown in FIGS. In the middle of a sheet carry-in path 17 extending from the sheet introduction section 16 to the intermediate tray 14, a conveying roller 18 driven in reverse rotation based on the re-feed information and the conveying roller 18 are used to transfer the image forming sheet to the intermediate tray. And a carry-in roller 19 that feeds the paper 14.

More specifically, in this embodiment, the number of the transport rollers 18 is three, and they are disposed so as to face each other at the upper portion of the intermediate tray 14 on the free end side.
Are two and are in contact with the transport rollers 18 on both the left and right sides. Further, above the intermediate tray 14, there is disposed a paper carry-out path 20 for causing the paper stocked in the intermediate tray 14 to be merged and fed to the paper feed path 7.

Further, based on the refeed information, the sheet lifting means 21 for pressing the uppermost sheet stocked in the intermediate tray 14 against the transport roller 18 and the double feeder contacting the central transport roller 18 are provided. Prevention roller 22,
The transport roller 18 that is driven to rotate in reverse with the double feed prevention roller 22
When the stock sheet is re-fed by the above operation and the stock sheet reverses the sheet carry-in path 17, there is provided a path switching unit 23 for bypassing the sheet to the sheet carry-out path 20.

The above-described paper lifting means 21 pivotally attaches a lifting member 24 having an L-shape in a side view to brackets 26, 26 provided on an apparatus main body 25 near a bent portion thereof, and lifts the lifting member 24. Pin 27 on the upper end of member 24
And a pin 29 is also connected to the cam 28 which rotates half a time based on the refeed information, and a spring 30 is connected across the two pins 27, 29.
The intermediate tray 29 is mechanically connected by a link 31 having one side pivotally connected to a long hole a, and the intermediate tray 14 is lifted by the half-rotational movement of the cam 28 based on the refeeding information. The stock paper is transported on the way
When pressed, the spring 30 absorbs the subsequent rotational movement of the cam 28.

The double feed prevention roller 22 has one end held by a pair of T-shaped arms 32 pivotally attached to the apparatus main body 25, and the other end of the T-shaped arm 32 has a double feed prevention roller. Spring 3 for pressing roller 22 against conveyance roller 18
3 are connected, and a cam follower 34 that contacts the cam 28 is provided over both arms 32, 32, while the cam 28 conveys the double feed prevention roller 22 against the urging force of the spring 33. It has a cam surface that separates from the roller 18 and a cam surface that causes the double feed prevention roller 22 to abut the transport roller 18 when it makes a half rotation based on refeed information.

In the paper feeder 12 having the above-described configuration, when forming a one-sided image, the path switching means 13 on the printer side is switched to a paper feed mode to the paper discharge path 11 side.
The sheet after the single-sided image formation is taken out to the sheet discharge tray 10.

When forming a two-sided image, the path switching means 13 on the printer side is switched to a paper feeding mode to the paper introduction unit 16, and the paper after the one-sided image formation is temporarily stored in the intermediate tray 14 through the paper carrying path 17. You.

Then, based on the re-feed information for forming an image on the other side, the double feed prevention roller 22 is brought into contact with the transport roller 18 and the re-feed paper is fed to the paper discharge path 20.
The path switching means 23 is switched by the solenoid 35 so as to detour to the side, and the intermediate tray 14 is lifted by the paper lifting means 21 so that the uppermost sheet stocked in the intermediate tray 14 is pressed by the transport roller 18. Path switching means 13 on the printer side
Is switched to the paper discharge mode to the paper discharge tray 10 side.

Next, at a predetermined timing, the transport rollers 1
8 is driven in the reverse direction, and the double feed prevention roller 22 is driven in the direction opposite to the conveyance roller 18 so that the intermediate tray 1 is rotated.
When the number of sheets stocked in the sheet 4 is plural, the uppermost sheet is sequentially taken out to the sheet carry-out path 20 in a state of preventing double feed, and the sheet passes through the sheet feed path 7 and is The sheet on which the double-sided image has been formed in this manner is turned over and re-fed to the image forming section of the image forming unit 3. Will be taken out.

Here, when a paper jam occurs in the paper carry-in path 17 at the time of paper supply to the intermediate tray 14, the paper feed drive system is electrically stopped based on the detection of the paper jam, and The occurrence of a jam is displayed.

On the other hand, if a paper jam occurs during refeeding of the stock paper, in addition to the stop of the paper feed drive system and the indication of the occurrence of the paper jam, the double feed prevention roller 22 is separated from the transport roller 18 and The sheet lifting means 21 that lifts the intermediate tray 14 is lowered, and the pressing of the stock sheet against the transport roller 18 is released.

In the paper feeding device 12 having the above-described structure, the jam occurring in the paper carrying path 17 can be easily removed.
As shown in FIG. 5, the other path component 37 is provided movably in the path opening direction with respect to the path component 36 on the apparatus main body side constituting the paper carrying path 17. The carry-in roller 19 is configured to be separated from the transport roller 18 with the opening movement.

FIG. 6 is a diagram showing a configuration of the detour path 38 formed by the transport roller 18 and the path switching means 23. As shown in the drawing, a detour path component (the transport roller 18 in this embodiment) 39 on the apparatus main body side of the detour path 38 is opposed to the other detour path component provided with the path switching means 23 (this embodiment). In the embodiment, the path constituting member 36 on the apparatus main body side constituting the paper carrying path 17) is provided so as to be movable in the path opening direction.

More specifically, the other path constituting member 37 is locked and connected to the first support shaft 41 on the apparatus main body side from above so as to be swingable in the path opening direction. 3
7 is pivotally mounted on a second support shaft 43 on the lower side of the apparatus main body parallel to the first support shaft 41 so as to be swingably openable and closable. Are interlocked by an interlocking mechanism 44 that allows synchronous swing of the two 42 and 37 over a predetermined range, and further, cover fixing means 45 for fixing the outer cover 42 in a closed posture is provided.

Further, the other detour path member 40 provided with the path switching means 23 is provided so as to be movable around the first support shaft 41 in the path opening direction, and the other detour path member 40 forms the detour path 38. In the configured state, a fixing means 46 for fixing the other detour path constituting member 40 to the apparatus main body side is provided.

A support shaft 48 is held between the bracket 26 and the side plate 47 of the apparatus main body 25, a pair of links 49 are set up on the support shaft 48, and a roller shaft provided with a carry-in roller 19 on both sides. 50 is passed through the long holes (see FIG. 7) b of the brackets 26, 26 to connect the bent links 51, 51 over the roller shaft 50 and the link 49, and to connect the carry-in roller 19 to the transport roller 18 A spring 52 for urging and contacting the bracket 26 is held by the bracket 26 as a pin.

Further, a link 53 is raised at the end of the support shaft 48, and the link 53 and the outer cover 42 are connected by a link 54 having one of the slots c as a pivot structure.

The interlocking mechanism 44 is provided with a locking pin 55 connected to the upper side of the other path constituting member 37 and an elongated hole d formed for engaging the locking pin 55. The forming member 56 is connected to the exterior cover 42, and
The pin-engaging slot c is provided in the movement locus of the locking pin 55 around the second support shaft 43 so that the other path component member 37 swings synchronously with the opening and closing of the outer cover 42. I try to follow it.

The cover fixing means 45 for fixing the outer cover 42 in the closed position is provided with a fixing pin 57 on the apparatus main body side, and a hook 58 for locking the fixing pin 57 from below is pivotally attached to the outer cover 42. A cover opening handle 59 is connected to the hook 58 and a cam surface is formed at the tip of the hook. The handle 59 is pulled against the urging force of a return spring (not shown). While the outer cover 42 is closed, the cam surface at the tip of the hook comes into contact with the pin 57 as the outer cover 42 is closed, whereby the hook 58 swings downward once, and then the hook 58 engages with the pin 57. By stopping, the exterior cover 42 is fixed to the apparatus main body side.

The fixing means 46 for the other detour path constituting member 40 has almost the same structure. A fixing pin 60 is provided on the apparatus main body side, and a hook 61 for locking the fixing pin 60 from the side is provided on the other side. It is pivotally connected to the detour path component 40, has a handle 62 connected to the hook 61, and has a cam surface formed at the tip of the hook. The cam surface is formed against the urging force of a return spring (not shown). The lock 62 is released by swinging the handle 62, while the cam surface at the tip of the hook comes into contact with the pin 60 as the other detour path constituting member 40 is closed, whereby the hook 61 swings laterally once. After that, the hook 61 is locked by the pin 60, so that the other detour path constituting member 40 is fixed to the apparatus main body side.

According to the above configuration, the cover fixing means 45
The fixing of the exterior cover 42 by the
2, the other path constituting member 37 opens the sheet carry-in path 17 in synchronization with this, and the link 5
4, 53 and the support shaft 48 and the link 49 and the bending link 51
, The carry-in roller 19 separates from the transport roller 18 with a delay corresponding to the dimension of the long hole c.

That is, by a one-touch operation of releasing the fixing and opening the outer cover 42, the paper carrying path 17 is opened, and the nip between the rollers 18 and 19 is released. That is, when the roller shaft 50 comes into contact with the end of the elongated hole b, the open state is maintained.

Therefore, if a paper jam occurs during the paper feeding to the intermediate tray 14, when the outer cover 42 is opened, the nip between the rollers 18 and 19 is released. The other path constituting member 37 without tearing the sheet.
Can be performed in a comfortable posture by looking into the open space from above.

On the other hand, in the case where the re-feeded paper traveling backward in the paper carry-in path 17 is jammed in the bypass path 38, the above-described jam processing mode is taken, that is, the paper carry-in path 17 is opened and both rollers are opened. After releasing the nip between the sheets 18 and 19, the fixing of the other detour path component 40 by the fixing means 46 is released, and the other detour path component 40 is moved in the path opening direction. As a result, the path switching means 23 which obstructs the sheet pull-out is separated from the transport roller 18, and the double feed prevention roller 22 is separated from the transport roller 18 based on the detection of the jam, and the intermediate tray 14 is lowered to reduce the stock paper. Is released, jamming of the re-feeded paper can be easily and easily performed without tearing the paper.

After the jam has been cleared, the other detour path constituting member 40 and the outer cover 42 are sequentially closed by one-touch operation in the reverse procedure to the above, and the respective members are fixed by fixing means 45, 45. When the cover 42 is closed, the other path constituting member 37 is also closed at a stroke.

The outer cover 42 and the other path component 37 are made to swing in synchronization with each other, so that when the outer cover 42 is in the closed state, the other path component 37 is loaded with paper. If the path 17 is formed, by fixing only the exterior cover 42, the other path constituent member 37 is also fixed at the same time, and therefore, the other path constituent member 37 with respect to the apparatus main body 25. Can be omitted.

[0043]

As described above, according to the paper feeder of the first aspect, when a paper jam occurs in the paper carry-in path at the time of paper supply to the intermediate tray, the path configuration on the apparatus body side. When the other path constituting member is moved in the path opening direction with respect to the member, the carry-in roller is separated from the transport roller in conjunction with this movement, and the nip of the sheet by both rollers is released, so that the jammed sheet is removed. The pull-out process can be easily performed without causing the paper to tear.

According to the second aspect of the present invention, if a paper jam occurs during re-feeding of the stock paper, the above-described paper jam handling mode is taken, and the paper is fed to the bypass path constituting member on the apparatus body side. When the other detour path constituent member is moved in the path opening direction, the path switching means that hinders the sheet pull-out is separated from the transport roller, thereby performing the jam processing of the re-feed sheet and the tearing of the sheet. It can be done easily and easily without accompanying.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram illustrating a paper feeding mode of a printer mounted on a paper feeding unit.

FIG. 2 is an explanatory diagram illustrating a sheet feeding mode when a sheet feeding device forms a double-sided image.

FIG. 3 is a developed plan view of a main part of the sheet feeding device.

FIG. 4 is a side view of a main part of the sheet feeding device.

FIG. 5 is an explanatory diagram of a jam processing of a single-sided image forming sheet generated in a sheet carrying-in path.

FIG. 6 is an explanatory diagram of a jam processing of a re-feed sheet generated in a bypass route.

FIG. 7 is an explanatory diagram of attachment of a carry-in roller.

[Explanation of symbols]

14: Intermediate tray, 16: Paper introduction section, 17: Paper carry-in path, 18: Transport roller, 19: Carry-in roller, 20: Paper carry-out path, 21: Paper lifting means, 22: Double feed prevention roller, 23: Path switching Means, 36: path component on the device main body side, 37: other path component, 38: detour path, 39: detour path component on the device main body side, 40: other detour path component.

Claims (2)

(57) [Claims] 1. A conveyance roller that is driven in reverse rotation based on refeed information in the middle of a paper conveyance path from a paper introduction unit to an intermediate tray, and a conveyance roller that feeds image forming paper to the intermediate tray by the conveyance roller. And, and
A paper carry-out path for re-feeding the sheets stocked in the intermediate tray to the image forming unit is arranged at the upper part of the intermediate tray, and the topmost stock sheet is conveyed based on the re-feed information. A sheet feeding device comprising: a sheet lifting unit that presses against a roller; a double feed prevention roller that abuts on the conveyance roller; and a path switching unit that detours a sheet that reverses the sheet conveyance path to a sheet conveyance path. For the path component on the apparatus main body side that constitutes the path, the other path component is provided so as to be movable in the path opening direction, and with the path opening movement of the path component, the carry-in roller is moved from the transport roller. A sheet feeding device configured to be separated from the sheet feeding device. 2. The detour path component provided with the path switching means can be moved in the path opening direction with respect to the detour path component on the apparatus body side of the detour path formed by the transport roller and the path switching means. The sheet feeding device according to claim 1, wherein