JP3510883B2 - Sheet conveying device of image forming apparatus - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet conveying device used in an image forming apparatus or the like, and is capable of easily removing a jammed sheet when the sheet is jammed (jammed) in the conveying path. Concerning a carrier device.

[0002]

2. Description of the Related Art In an image forming apparatus, for example, an image forming apparatus using an electrophotographic method, a toner image is formed on a photosensitive member which is a recording medium, and the toner image is transferred onto a sheet such as plain paper. In order to hold the upper toner image on the sheet as a permanent image, the toner is fixed by passing it through, for example, a heat fixing device, and then discharged to the outside of the apparatus main body.

According to such an image forming apparatus, it is necessary to convey the sheet to the image forming position in order to form a desired image on the sheet. For example, a large number of sheets are accommodated in a paper feed cassette or tray, and the sheets are sent one by one from the cassette or tray to an image forming unit, particularly to a conveyance path leading to a transfer position for transferring a toner image formed on a photoconductor. The sheet conveying device thus configured is provided.

According to the above-described sheet conveying device, although it is necessary to feed the sheet to a target position, it may be jammed by being caught in the sheet conveying path depending on the state of the sheet. In order to remove the jammed sheet, the sheet conveying device is configured so that the sheet conveying path for guiding the sheet to a target position can be opened. Therefore, the jammed sheet is easily removed by opening the sheet conveying path.

For example, in the apparatus described in Japanese Patent Application Laid-Open No. 7-215531, one wall surface (exterior cover) of the image forming apparatus is provided so that it can be opened, and a part of the sheet conveying path is opened according to the opening. The jam sheet is easy to remove. To explain this example with reference to FIG. 4, one side portion (36) which is an exterior of the image forming apparatus is provided on the main body of the image forming apparatus (1) so as to be rotatable around a fulcrum (37). One guide plate (46) forming the sheet conveyance path (35) provided on the one side portion (36) is also opened together. As a result, the sheet conveyance path (35) is opened, and the sheet jammed at that position can be easily removed.

On the other hand, in order to make it easier to remove the jammed sheet, in the one disclosed in Japanese Patent Laid-Open No. 7-157141, if a sheet jam occurs at the fixing portion, a fixing roller or the like will be used. Is stopped, and the upstream sheet conveying means, in this example, the photoconductor and the transfer roller, are rotated for a certain period of time in order to feed the jammed sheet in the sheet conveying direction. After this fixed time, the drive is stopped and a jam message is issued. As a result, the bending of the sheet is formed on the upstream side of the fixing device so that the sheet can be easily removed.

[0007]

As described above, in the sheet conveying apparatus provided in the conventional image forming apparatus, it is devised to easily remove the jammed sheet.

In particular, as described with reference to FIG. 4, the outer cover gabber (36) is opened and at the same time the sheet conveying path (3) is opened.
Since a part of 5) is open, the jammed sheet is exposed in the open space, which facilitates the processing. However, the sheet being conveyed is not necessarily bent, and the sheet is in close contact with the other guide plate forming the sheet conveying path, or the sheet is held and stretched on the upstream and downstream sides. If it is in the open state, removal of the jam sheet becomes very troublesome. In addition, when the sheet is removed by using a user's finger or a removing tool, there is a risk of damaging the photoconductor or the like when the sheet is forcibly peeled off or pulled.

Therefore, as described in Japanese Patent Application Laid-Open No. 7-157141, when a sheet jam is detected, the conveying means is driven for a certain period of time without issuing a jam message.
Bending may be formed on the jam sheet. However, in this case, the time from the time when the sheet is jammed until the user is notified of the jam message is naturally delayed. If the jam message is notified first, it is considered that the conveying means is being driven when the user opens the sheet conveying path, which is very dangerous.

Therefore, it is necessary to inform the user of the jam message after the driving of the conveying means is completely stopped, and the jam process is delayed. Further, if the sheet jam occurs on the downstream side, the conveying means on the upstream side is driven, so that the sheet can be bent. However, when the sheet is jammed on the upstream side, it is necessary to drive the conveying means on the downstream side in the opposite direction, so a mechanism for rotating the conveying means in the reverse direction and control are required, and the structure is complicated,
And control becomes troublesome.

Further, a sheet jam occurs on the downstream side,
Even if the upstream conveying means is driven for a certain period of time, it cannot be expected that the sheet will surely be bent. That is, it is possible that the sheet cannot be conveyed even if the upstream side is driven for a certain period of time due to a sheet jam. Moreover, it is possible that the jammed sheet is damaged by driving the upstream conveying means, or a part of the damaged sheet cannot be removed in the conveying path and becomes stagnant. This causes a new jam occurrence factor.

The present invention has been made in view of the above-mentioned conventional problems.
An object of the present invention is to provide a sheet conveying device configured so that a jammed sheet can be easily and surely removed in a sheet conveying path in an image forming apparatus.

Another object of the present invention is to provide a sheet conveying device in which a jammed sheet is positively bent in order to facilitate the removal of the jammed sheet.

Further, another object of the present invention is a sheet conveying apparatus which is capable of forming a bending of a sheet in association with an opening operation of a sheet conveying path without driving and controlling the conveying means when jammed. It is provided.

[0015]

According to another aspect of the present invention, there is provided a sheet conveying device for an image forming apparatus, which conveys a sheet to an image forming position, and after the image is formed, the image forming apparatus. A sheet transporting device for discharging to the outside, wherein a sheet transporting path of the image forming apparatus is provided so that a sheet transporting path can be opened to facilitate removal of jammed sheets. The first guide plate is opened in conjunction with the opening operation of the exterior, and the other second guide plate is rotatably provided on the side of the first guide plate in a rotatable state. The second guide plate is simultaneously rotated toward the sheet conveying path side in association with the opening operation.
A projecting portion is provided in a region of the guide plate or the second guide plate that is not involved in guiding the sheet, and abuts on the first positioning member provided on the first guide plate side, corresponding to the positioning member. A second positioning member provided on the image forming apparatus side is provided, the protrusion does not participate in positioning the exterior, and restricts rotation of the second guide plate, and the positioning member is the image forming apparatus. And the first guide plate is compensated for the positional relationship.

According to this structure, the sheet is guided along the sheet conveying path and is reliably fed to the target position. If a sheet conveyance failure, that is, a jam occurs during this process, the sheet stays in the sheet conveyance path. In order to remove this sheet, by opening a part of the exterior of the image forming apparatus, at the same time, one of the first guide plates forming the sheet conveying path is opened, and the sheet conveying path is exposed to the outside in an exposed state. It Then, in association with this opening operation, the other second guide plate which is rotationally biased is simultaneously rotated. Therefore, the sheet retained in the sheet conveyance path is pushed in the opening direction by the second guide plate. As a result, even if the sheet is brought into close contact with the guide plate or the like by triboelectric charging or the like, a curved flexure is partially formed. The sheet can be easily removed by holding the bent portion. Therefore, the jam sheet can be reliably removed.

In this case, by providing an urging member on the second guide plate, the action of pushing the sheet in close contact with the guide plate in the opening direction is forced. Therefore, the effect of forming the bending of the sheet can be promoted. Further, in the case where the sheet conveying direction is formed in the vertical direction, as compared with the case where the sheet is biased by its own weight, if the configuration is such that the sheet is forcibly biased by rotation,
The action described above is further promoted.

Further, in the sheet conveying device of the image forming apparatus having the above-mentioned structure, according to the invention of claim 2, when the projecting portion returns the first guide plate to the original position. Is brought into contact with the first guide plate or the second guide plate and is rotated by the second guide plate to return to the original position. After the second guide plate is returned, the two guide plates are formed. The second guide plate is characterized by restricting the rotation of the second guide plate, and when the second guide plate is returned to its original position after removing the jammed sheet, both guides can be secured. The sheet conveyance path formed by the plate can be secured by the protrusion, and at the same time, the second
Since the urging force of the guide plate comes into contact with the protrusion and is regulated, the rotation can be easily regulated.

Further, in the sheet conveying device of the image forming apparatus having the above-mentioned constitution, according to the invention of claim 3, the sheet conveying path is formed in the vertical direction, and the second guide plate side is The biasing member is naturally provided by being provided so as to be rotated toward the first guide plate side by its own weight and being related to the opening operation of the first guide plate so that the second guide plate is rotated by its own weight. There is no need to install a separate
Very easy to configure.

Further, as a sheet conveying device of an image forming apparatus as another embodiment for attaining the above-mentioned object of the present invention, a sheet is conveyed to an image forming position, and after the image forming, it is outside the image forming apparatus. In the sheet conveying device of the image forming apparatus, which is configured to open the sheet conveying path to facilitate the removal of the jammed sheet, one of the sheet conveying apparatus for forming the sheet conveying path. The first guide plate is configured to be opened in association with the opening operation, and can be projected from the sheet guide surface of the guide plate with respect to other guide plates provided on the image forming apparatus main body side, and is rotatable. A biased auxiliary lever may be provided so that the auxiliary lever is simultaneously projected from the sheet guide surface of the second guide plate in association with the opening operation.

Even in such a structure, when the sheet is jammed and stays in the sheet conveying path, the exterior of the image forming apparatus is opened. In conjunction with this opening operation, the first guide plate is separated from the sheet conveying path by a large distance. Also, the second
On the guide plate side, the auxiliary lever is released from the rotation restriction, and is rotated so as to project from the sheet guide surface of the second guide plate. As a result, as described in the first aspect of the invention, the sheet is pushed in the opening direction and the sheet P
Bending can be formed in a part of the sheet, so that the sheet can be easily and surely removed.

In a sheet conveying device of an image forming apparatus characterized by the configuration of another embodiment described above, according to still another embodiment of the invention, the second guide plate is rotated to the image forming apparatus main body side. It is movably provided so as to be urged to rotate in the opening direction, and is simultaneously rotated in association with the opening operation. Thus, the second guide plate together with the auxiliary lever is simultaneously rotated in association with the opening operation of the exterior of the image forming apparatus, that is, the sheet is rotated in the direction of pushing the sheet in the opening direction. As a result, the bending of the sheet can be further increased, and the sheet removing operation can be performed more easily and reliably.

[0023]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described below in detail with reference to the drawings. FIG. 1 is a configuration diagram showing in detail a part of a sheet conveying path constituting a sheet conveying device according to the present invention, and FIG. 2 is a diagram for explaining a jam sheet removal state by the sheet conveying device according to the present invention. It is a figure. Further, FIG. 3 is a configuration diagram showing the overall structure of an image forming apparatus including the sheet conveying apparatus as shown in FIG.

First, referring to FIG. 3, an image forming apparatus according to the present invention will be described. This image forming apparatus 1
Is a digital copier equipped with a laser printer section,
The present invention is not limited to only the sheet conveying device in a digital copying machine, but can be generally applied to all sheet conveying devices for feeding a sheet to a required position. Further, the image forming apparatus is not limited to an electrophotographic printer based on a normal electrophotographic method, but includes an inkjet printer that forms an image by ejecting ink, a thermal printer that forms an image by thermal transfer, and the like. There are facsimile machines and the like. As a sheet conveying device for feeding a sheet to a target position in these devices, the sheet conveying device of the present invention described below can be applied as it is.

The main body of the image forming apparatus 1 shown in FIG. 3 is a drum-shaped photosensitive member 2 which is a recording medium having a photoconductive layer formed on the surface which rotates in the direction of the arrow as shown in the figure.
On the other hand, a charger 3 for uniformly charging the surface along the rotation direction, an exposure unit 4 for imagewise exposing the surface after charging, a developing unit 5 for developing the electrostatic latent image formed by the exposure, A transfer device 6 for transferring the toner image to the sheet and a cleaning device 7 for removing the residual toner after the transfer are arranged to face each other.

The exposure unit 4 for imagewise exposing the surface of the photoconductor 2 irradiates the surface of the photoconductor 2 with a laser beam 9 by a laser irradiation device 8. The laser irradiation device 8 drives a semiconductor laser ON-OFF according to input image data, and a polygon mirror 10 which is a polarizer causes a laser beam 9 to be directed in the rotation axis direction of the photoconductor 2 to other mirrors and lenses. And so on. As a result, the laser beam 9 is applied to the surface of the photoconductor 2 uniformly charged by the charger 3.
Is irradiated, and an electrostatic latent image corresponding to the image is formed.

The electrostatic latent image formed on the photoconductor 2 is visualized by the toner in the developing device 5, and the visualized toner image is fed through the sheet conveying system according to the present invention. The sheet is transferred to the sheet by the action of the transfer device (or transfer roller) 6.

Further, in order to irradiate the photoconductor 2 with an optical image by the laser beam 9 according to the image data, a scanner 11 for optically reading an image of a document is provided above the main body of the image forming apparatus 1. ing. The scanner 11 has a well-known structure, and includes a transparent platen 12 for placing an original on its image side, an original cover 13 for pressing the original placed on the transparent platen 12 from above, and a transparent cover. An exposure lamp 14 for illuminating the image surface of the original from below the platen 12, a first reflecting mirror 15 for reflecting the reflected light from the original to a desired position, and an image of the reflected light from the first reflecting mirror 15 A pair of second and third reflection mirrors 16 and 17 that reflect toward the lens side, an imaging lens 18 that forms an image on a light receiving surface of a CCD that is a reading element that converts a light image of reflected light into an electric signal, and reading. It is composed of a CCD 19 as an element.

The first reflection mirror 15 and the exposure lamp 1
Reference numeral 4 is provided in the same scanning means, and is driven to travel in the arrow direction with respect to the transparent platen 12. The second scanning means, which supports the second and third reflecting mirrors 16 and 17 with respect to the scanning means, is driven to travel at a speed half the traveling speed of the scanning means. As a result, the images of the original are sequentially formed on the light receiving surface of the CCD 19. Therefore, the CCD 19 sequentially outputs electric signals corresponding to the image of the document as image data.

The image data is sent to an image processing circuit provided in a part of a control circuit board 20 for controlling the entire image forming apparatus 1, and the laser beam 9 in the image forming apparatus 1 described above is transmitted. The surface of the photoconductor 2 is irradiated with light and processed as data for obtaining a corresponding image.
The data after this processing is finally sent to the laser irradiation device 8 as image data.

According to the above description, the image forming apparatus 1 functions as a digital copying machine, but it can also function as a printer. That is, the image forming apparatus 1
Receives image data from another image input device (facsimile device, personal computer, other scanner, etc.) via a communication line, and processes this as image data capable of forming an image on the image forming device 1 side as described above. Then, the desired image can be arbitrarily obtained by being sent to the laser irradiation device 8.

Next, in the image forming apparatus 1 described above, a sheet for transferring the image formed on the surface of the photoconductor 2, that is, the toner image, to the sheet P and finally outputting the image to the outside of the image forming apparatus 1. The transport system will be described. The sheet conveying system feeds the sheet to a transfer position which is a target position facing the transfer device 6 as described above, and after transfer, the sheet is separated from the photoconductor 2 and the main body of the image forming apparatus 1 via the heat fixing device. This is for conveying and discharging the sheets one by one to a discharge tray provided in the middle portion.

Then, the sheet conveying apparatus according to the present invention for feeding the sheet to the transfer position will be described.
The sheet conveying device is provided with a registration roller 21 for feeding in synchronization with the rotation of the photoconductor 2.
This is located in front of the transfer position (upstream side),
In order to feed the sheet to the registration roller 21, the sheet feeding device 22 which constitutes a part of the sheet conveying device,
It is provided further upstream.

The sheet feeding device 22 is provided in the lower portion of the main body of the image forming apparatus 1, that is, on the upstream side of the registration roller 21, and if necessary, another sheet for feeding another sheet. A feeding device is provided so that it can be attached to the lower portion of the main body of the image forming apparatus 1 if necessary. Further, in the main body of the image forming apparatus 1 shown in FIG. 3, although not shown in the drawing, a manual sheet feeding device or the like may be provided so as to project rightward.

The sheet feeding device 22 has, for example, in FIG. 3, a sheet feeding cassette or tray 23 that is provided in the front side of the image forming apparatus 1 so as to be drawn out, and a sheet of a predetermined size can be loaded. It is configured to house. Therefore, a mounting plate 24 for mounting the sheets accommodated in the cassette is provided. The mounting plate 24 is rotatably supported on the side opposite to the position facing the sheet feeding roller 25, and is rotated so as to be constantly biased upward by a biasing means (not shown) such as a spring. Have been moved. Separation claws 26 are provided at both corners of the leading end of the mounting plate 24 on the sheet feeding side. The separation claws 26 restrict the floating of the sheet P on the mounting plate 24, and the uppermost portion of the sheet P. The position is always kept at a constant height.

In the non-paper feed state, the paper feed roller 2
As shown in FIG. 3, the string 5 of the sheet feeding device 5 faces the sheet P on the mounting plate 24.
Can be taken in and out in this state. When the paper feed state is reached, the arc portion of the paper feed roller 25 comes into contact with the uppermost sheet on the placing plate 24, the placing plate 24 is pushed down, and the uppermost sheet P of the sheet feeding roller 25 is pressed. Paper is gradually fed at the arc portion, and both corners of the uppermost sheet pass over the separating claw 26 described above to feed one sheet.

The sheet P fed by the paper feed roller 25 is guided by the guide path 27 to the registration roller 21 arranged on the downstream side and fed.
The guide path 27 is provided with a sheet detection sensor 28 that detects the sheet P fed to the registration rollers 21. The sheet detection sensor 28 outputs a signal for detecting the leading edge of the sheet P, and the output is used to control the rotation of the registration roller 21.

That is, when the sheet detection sensor 28 arranged in front of the registration roller 21 detects the leading edge of the fed sheet P, the signal is received and the driving of the registration roller 21 is temporarily stopped. In particular, the registration roller 21 is stopped and controlled with the leading edge of the sheet P being nipped. The front end of the toner image formed on the photoconductor 2
It is controlled to restart the feeding of the sheet to the transfer position at the timing when the leading edge of the sheet P waiting on the registration roller 21 coincides.

As described above, the sheet feeding and the feeding control to the transfer position facing the photoconductor 2 are performed,
The toner image formed on the photoconductor 2 is transferred onto the sheet P by the action of the transfer device 6. After this transfer,
The sheet P is separated from the photoconductor 2 and is disposed in the upper portion of FIG.
Is being transported to. The configuration of the heat fixing roller 29 is well known in the related art, and the roller side facing the toner image surface of the sheet is a heat roller maintained at a fixing possible temperature, and a heating roller for pressing the sheet to the heat roller is used. And a pressure roller.

The toner image carried on the sheet that has passed through the heat fixing roller 29 is fused and fixed. Then, finally, the discharge process is performed via the discharge roller 32 which is guided to the discharge path 31 on the discharge tray 30 arranged outside the image forming apparatus 1 and is positioned at the discharge port. The sheet detection sensors 33 and 3 for detecting the feeding state of the conveyed sheet in correspondence with the paths relating to the sheet discharge processing, that is, the positions of the heat fixing roller 29 and the discharge roller 32.
4 are provided respectively.

On the other hand, in the above-described sheet conveying device,
In order to easily perform the work of removing the sheet jam in the sheet conveying path constituting the conveying device, the sheet conveying path, particularly the sheet conveying path 35 from the registration roller 21 to the transfer position corresponding to the transfer device 6, is opened. Is configured to. In other words, the exterior (side cover or door) 36 that constitutes one side of the main body of the image forming apparatus 1 corresponding to the sheet conveying path 35 is opened in association with the opening.

That is, the exterior 36 is rotatably supported on the lower portion of the main body of the image forming apparatus 1 about the shaft portion 37. An engaging claw 39 that engages with a lock member 38 provided on the main body side of the image forming apparatus 1 is provided at an end portion of the exterior 36 opposite to the support portion 37. This lock member 3
A lock mechanism 40 is configured by 8 and the locking claw 39.

Locking member 38 constituting the locking mechanism 40
Has a claw portion that engages with the locking claw 39, and one end thereof is rotatably supported by a shaft portion 41 provided on the main body side of the image forming apparatus 1 as shown in FIG. The spring 42 is urged to rotate counterclockwise in the drawing.
The lock member 38 is urged to rotate by a spring 42, but a positioning member (not shown) is provided to maintain the lock member 38 at the position shown in FIG. An operating lever 43 fixed to the lock member 38 is provided. With this operation lever 43, the lock member 38 can be unlocked by rotating it clockwise against the bias of the spring 42.

Therefore, the exterior 3 having the locking claws 39 attached thereto
6 side corresponds to the operation lever 43, and the lever 43
An opening 44 is formed so as to be inserted therethrough.
Therefore, in the state of FIG. 3, if the operation lever 43 inserted through the opening 44 is pushed down, the lock member 3
8 is rotated downward, and the engagement with the locking claw 39 is released (unlocked). Therefore, by rotating the exterior 36 in the clockwise direction in the drawing, it is opened as shown in FIG. At this time, the opening 44 acts as a handle when opening the exterior 36.

When the exterior 36 is closed, the locking claw 3
The lock member 3 held at the position shown in FIG.
By contacting the inclined surface of the tip of the lock member 8, the lock member 38 is rotated (pushed down) clockwise in FIG. 4 against the biasing force of the spring 42. Then, at the time when the two are coincident with each other at the claw portion, the lock member 38 is pressed by the urging force of the spring 42.
Is rotated to be in a locked state, and both are engaged with each other at a claw portion, and the exterior (door) 36 is locked in a closed state.

A guide plate 46 serving as a first guide of the guide plates 45 and 46 forming the sheet conveying path 35 connecting the registration roller 21 and the transfer area of the photoconductor 2 is held by the exterior 36 having the above-described structure. A supporting body 47 formed of is attached. The support 47 also holds the transfer device 6 arranged to face the photoconductor 2 at the same time. Therefore, the guide plate 46 is opened (rotated) in conjunction with the opening operation of the exterior 36, and the sheet conveyance path 35 is exposed to the outside of the main body of the image forming apparatus 1.

Therefore, if the jammed sheet P exists in the sheet conveying path 35, the exterior 36 is opened to be exposed to the outside of the image forming apparatus 1. As a result, the jam processing of the sheet P that is opened and exposed by the user can be easily performed.

(First Embodiment) In the above configuration,
Next, a first embodiment for easily removing a jammed sheet in a sheet conveying apparatus according to the present invention will be described in detail with reference to the drawings shown in FIGS. 1 and 2.

FIG. 1 shows in detail the structure for facilitating the removal of the jammed sheet P when there is a jammed sheet P in the sheet conveying path 35 of the above-described sheet conveying apparatus. First, with reference to FIG. 1 showing the details of the sheet conveying path constituting the sheet conveying apparatus, a first embodiment of the sheet conveying apparatus of the present invention will be described.

As described above, the sheet conveying path 35 is formed by providing the guide plates 45 and 46 which are arranged so as to face each other with a certain space therebetween. The guide plate 45 constitutes a second guide,
The upstream side in the sheet conveying direction is rotatably supported on the image forming apparatus 1 main body side via a shaft portion 45a. This shaft 4
A kick spring 48 is wound around 5a, one end of which is locked to the back surface of the guide plate 45 (the surface on the side opposite to the sheet conveying path 35), and the other end is biased to rotate the guide plate 45. It is locked to a regulation pin 49 that regulates the rotation when rotating. As a result, the guide plate 45 is normally provided with a clockwise biasing force in FIG.

The other guide plate 46 for forming the sheet conveying path 35 with respect to the guide plate 45 is fixed to a holding member 47a provided on a support body 47 attached to the exterior 36. In order to maintain a constant distance between the guide plate 46 and the guide plate 45,
Protrusions 46a are integrally formed on the sheet conveying path 35 side at both ends that are not involved in guiding the sheet by the sheet conveying path 35. Therefore, the guide plates 45 and 46 are brought into contact with the projecting portion 46a by the biasing force of the kick spring 48 of the guide plate 45, and an interval determined by the projecting height (projecting amount) of the projecting portion 46a is maintained. The sheet conveyance path 35 is formed.

The guide plate 46 has the above-mentioned holding member 47a.
The holding member 47a is attached to the support body 47 via a connecting mechanism 50. Connection mechanism 5
0 is the holding member 47 on the side of the support 47 with respect to the locking portion 51 provided with a loop-back, for example.
An engaging piece 52 having a protruding claw that engages with the locking portion 51 is provided on the a side, and the folded portion and the claw portion of both are engaged with each other to connect them. This allows the exterior 3
The holding member 4 is attached to the support body 47 fixed to the 6 side.
7a is movably held. And the connection mechanism 5
A compression spring 53 for urging the holding member 47a toward the guide plate 45 side is provided inside 0.

The holding member 47a has a guide plate 46.
And the transfer device 6 is fixed at the same time. Then, in order to position the transfer device 6 with the photosensitive member 2 at a constant distance, the positioning portion 54 (first positioning member) corresponding to the upper and lower portions with respect to the sheet conveying direction.
Is provided. Corresponding to the positioning portion 54, a positioning pin 55 (second positioning member) with which the positioning portion 54 abuts is provided on the image forming apparatus 1 main body side. As a result, when the exterior 36 is closed to the main body of the image forming apparatus 1, the upper and lower positioning portions 54 come into contact with the upper and lower positioning pins 55, so that the positional relationship between the transfer device 6 and the photoconductor 2 is compensated. To be done.

Moreover, the holding member 47a is movably held by the support body 47 through the connecting mechanism 50, and the positioning portion 54 is urged by the biasing force of the spring 53.
The contact relationship between the and the positioning pin 55 can be reliably ensured, and the positioning accuracy is improved. Moreover, the sheet conveying path 35
The positioning of the guide plate 46 that forms the groove can be accurately performed, and at the same time, the guide plate 45 is brought into contact with the protruding portion 46a of the guide plate 46 by the rotational urging force of the kick spring 48, so that the positional relationship between them is also accurate. It is ensured and its positioning is also compensated.

When the sheet conveying path 35 constituting the sheet conveying apparatus is formed as described above and the image forming operation by the image forming apparatus 1 is started, the sheet feeding apparatus 22 makes the
A sheet P is fed. Then, the sheet P is restarted to be conveyed in synchronization with the rotation of the photoconductor 2 by the registration rollers 21, guided by the above-described sheet conveyance path 35, and fed to the transfer area of the photoconductor 2 facing the transfer device 6. Be done.
Further, the sheet P is peeled off from the photoconductor 2 after the toner image formed on the photoconductor 2 is transferred in the transfer area, passes through the heat fixing roller 29, the discharge path 31, and the discharge roller 32. The sheet is discharged to a discharge tray 30 located outside the image forming apparatus 1.

As described above, the sheets P are guided in the sheet conveying path 35 one by one in relation to the image forming operation. If the sheet P is jammed during the image forming operation, the image forming operation is stopped according to the jam detection. At this time, the power supply to all the loads except the necessary part, especially the control circuit part, is cut off. Therefore, the conveyance of the unjammed sheet P is also stopped midway.

For example, the sheet jam is the heat fixing roller 2
When it occurs at the position 9, the jam detection is performed while the sheet is detected with the sheet detection sensor 33 as the base point. Therefore, on the side of the main body of the image forming apparatus 1, although not shown, the user is informed of the jam on the display unit on the operation panel and the jam position.
Here, the jam detection is a well-known technique and it is not necessary to describe it, but it will be briefly described.

That is, the sheet P passes the position of the fixing roller 29, the leading edge of the sheet P is detected by the sheet detection sensor 33, and from that time point, the trailing edge of the sheet P is detected by the sheet detection sensor 3.
If the sheet P is not detected (state without a sheet) in 3 after a certain period of time, it is determined that the conveyance of the sheet P is stopped and the jam is detected. Further, when the conveyance of the sheet P is started while the leading edge of the sheet P is on standby at the registration roller 21, and the sheet detection sensor 33 does not detect the leading edge of the sheet P after passing through the fixing roller 29, the sheet P is in the middle. Jam detection will be carried out because of the stagnation. That is, the conveyance is started by the registration roller 21,
The time during which the sheet P is conveyed to the detection position of the sheet detection sensor 33 is constant. If the sheet is not detected even after the elapse of the certain period of time, it means that the sheet has stagnated on the way and thus is detected as a sheet jam.

When the sheet jam is detected as described above, the power supply to the various loads of the image forming apparatus 1 is stopped, the jammed message is displayed, and the user is notified of the trouble, that is, the jam sheet is removed. Urge.

In response to the jam message, the user opens the exterior 36 of the image forming apparatus 1 main body. For this release, the lock is released by the operation lever 43, and the lock is released as shown in FIG. Details of this state are shown in FIG.
The jam sheet removing operation will be described below with reference to FIG.

When the exterior 36 is opened, the one guide 46 forming the sheet conveying path 35 is also rotated in accordance with the exterior 36, and is separated from the guide plate 45 provided on the image forming apparatus 1 side by a large distance. The sheet conveying path 35 is opened so as to be exposed to the outside. Then, the guide plate 45 on the image forming apparatus 1 side is rotated by the urging force of the kick spring 48. This rotation causes the guide plate 4 to move to the regulation pin 49.
The lower part of the guide 5 abuts, and further rotation of the guide 45 is restricted.

In this case, if a sheet P stagnated due to a sheet jam exists in the sheet conveying path 35, the sheet P
As shown in FIG. 2, since the guide plate 45 is rotated in the direction in which the exterior 36 is opened, the sheet P is also pushed toward the opened side in accordance with the rotation, and the sheet P is loosened or Deflection a is formed. By holding the bent portion a, the stagnant sheet P can be easily removed.

Here, it is conceivable that the sheet P is frictionally charged by being pinched by the sheet feeding roller 25 and the registration roller 21 and frictionally applied. The guide plate 45 that forms the sheet conveyance path 35 by the sheet P by this frictional charging
Since the guide plate 45 is rotated in association with the opening operation of the exterior 36 even when being guided and conveyed so as to be in close contact with the sheet P, even if the sheet P is in close contact as shown in FIG. Since it is pushed out to the open position, the flexure a is formed. As a result, the work of removing the sheet is simple and easy.

Further, when the sheet P comes into close contact with the guide plate 45 or the like by frictional electrification, conventionally, the sheet is guided by the guide plate 45.
At the time of further peeling, there is a risk that the surface of the photoconductor 2 may come into contact with the hand of the user or a tool for peeling to cause scratches and the like. However, according to the above-described apparatus of the present invention, since the sheet P can be surely pressed by the guide plate 45 to form the curved flexure a, such a risk can be eliminated.

Moreover, by displaying a message when a jam is detected, the trouble can be resolved quickly. Further, since it is not necessary to drive a part of various conveying means of the sheet conveying device, the jammed sheet is not forcibly conveyed and is not damaged, and the damaged sheet remains and causes a jam. Disappear.

(Structural Example of Guide Plates 45, 46) The guide plates 45, 46 forming the sheet conveying path 35 for guiding the sheet constituting the sheet conveying device to a desired position are fixed as described above. Are arranged with a certain space.
Therefore, the guide plate 4 arranged to face the guide plate 46 side.
It has been described that the protrusion 46a is provided to secure a space between the protrusion 46a and the protrusion 5.

The protrusion 46a need not be provided on the guide plate 46 side, but may be provided on the guide plate 45 side. Further, the protrusions 46a may be provided on both sides of the guide plates 45, 46 side. FIG. 5 shows a detailed configuration of the guide plate 46 provided with the protruding portion 46a. Figure 5
FIG. 5A is a perspective view of the guide 46, and FIG. 5B is a side view of the guide plate 46 seen from the side.

As shown in FIG. 5, the guide plate 36 having a flat plate-shaped surface as a guide surface for the sheet P reduces the contact area of the guide surface with the sheet to improve the transportability, and at the same time as the sheet P. In order to reduce the adhesion of the sheet, a plurality of protruding ribs 46b are formed along the sheet conveying direction. Along with the ribs 46b, projecting portions 46a for securing a space between the guide plates 45 arranged opposite to each other are integrally formed at both ends of the guide plate 46. The rib 46b is formed to be slightly lower than the protruding surface of the protruding portion 46a.

In contrast to the guide plate 46, the guide plate 45 also has a flat guide surface of the sheet P.
If necessary, a plurality of ribs for the same purpose as the rib 46b having the protruding shape described above are formed. This allows
The sheet P is improved in transportability and is reduced in adhesiveness due to triboelectrification. Also, on the guide 45 side, similarly, a protrusion may be integrally formed at a position corresponding to the protrusion 46a provided on the guide plate 46.

As described above, by providing the ribs 46b on the guide surface side of the sheet conveying path 35 of the guide plates 45 and 46, it is possible to reduce the adhesion of the sheet P due to triboelectrification. When the exterior 36 is opened, the deflection a formed on the sheet P can be largely formed by the rotation of the guide plate 45. As a result, the sheet removing operation can be performed more reliably and easily.

When the ribs 46b and the like are provided on the flat plate-shaped guides 45, 46, the ribs 46b are not positioned so that the ribs are opposed to each other and the mating ribs are positioned between the ribs. Can be further improved.

The same effect can be expected by providing a plurality of slits (openings) along the sheet conveying direction in the flat guide plates 45 and 46 without providing ribs.

The projecting portion 46a of the guide plate 46 described above is
The sheet conveying path 35 can be surely secured, and the guide plate 45 is urged by the kick spring 48 so as to rotate.
5 is abutted and restricted in rotation, the guide plates 45, 46
The positional relationship of can be accurately secured.

(Second Embodiment) Next, a second embodiment according to the present invention will be described with reference to FIGS. 6 and 7. In the above-described first embodiment, the guide plate 45 is rotated in the opening direction in association with the opening operation of the exterior 36, and the curved flexure a of the sheet P is formed. Further, in the second embodiment, the action is promoted, the bending of the sheet P is effectively formed, and the jam sheet removing operation is facilitated.

In FIG. 6, the same parts as those in FIG. 1 are designated by the same reference numerals, and the description of the structure will be omitted. In particular Figure 6
The feature of the sheet conveying device shown in (4) is that the guide plate 45 protrudes from the sheet guide surface side of the guide plate 45 in accordance with the operation of rotating the guide plate 45 by rotationally biasing it in conjunction with the opening operation of the exterior 36. The point is that the auxiliary lever 60 that is rotationally biased is provided.

As shown in FIG. 7, the auxiliary lever 60 is constructed by fixing a plurality of levers 61 to a shaft portion 62 at equal intervals. The shaft portion 62 is rotatably supported on the main body of the image forming apparatus 1. The lever 61 is positioned so as to correspond to the plurality of openings provided in the guide plate 45 to improve the transportability and the like described above.

An arm 63 for biasing the rotation is fixed to one end portion or both end portions of the shaft portion 62. The arm 63 is provided with a spring 64 that applies a biasing force to rotate the auxiliary lever 60 in the clockwise direction in FIG. The other end of the spring 64 is locked to the image forming apparatus 1 side.

The arm 63 corresponds to another projecting portion (not shown) provided on the side of the one guide plate 46 that forms the sheet conveying path 35.
The arm 63 in FIG. 7 is locked, the rotation bias by the spring 64 is restricted, and the auxiliary lever 60 is held at the position indicated by the solid line. That is, each lever 61 forming the auxiliary lever 60 is provided so as not to project into the sheet conveyance path 35. Even in the projecting state, if the biasing force of the spring 64 is very weak, or if the sheet conveyance is not hindered, there is no particular problem with the projecting state.

Therefore, when a sheet jam occurs, the exterior 36 is opened in order to remove the sheet P stagnant in the sheet conveying path 35. In conjunction with this opening operation, the guide plate 46 moves the guide plate 4 on the main body side of the image forming apparatus 1.
Separate more than 5. At the same time, the guide plate 45 is also rotated clockwise by the kick spring 48. At the same time, the auxiliary lever 60 is also rotated by the side of the guide plate 45 to cause the arm 6 to move.
The locked state of 3 is released, and it is rotated clockwise by the urging force of the spring 64. At this time, if the rotation of the auxiliary lever 60 is restricted, for example, at the lower edge of the opening of the guide plate 45, each of the plurality of levers 61 is guided by the guide plate 4.
5 is projected more than the sheet guide surface side.

In particular, the guide plate 45 contacts the regulation pin 49 and stops at the rotating position shown in FIG. On the other hand, the auxiliary lever 60 is rotated by the urging force of the spring 64 until the lower portion of each lever 61 comes into contact with the lower edge of the opening of the guide plate 45, and the rotation is restricted at that position. Therefore, since each lever 61 projects more than the guide surface of the guide plate 45, the sheet P is formed to have a larger bending deflection a as shown in FIG.

The sheet P jammed as described above
When the exterior 36 is opened, a larger deflection a can be formed on the sheet P by the auxiliary lever 60. As a result, the work of removing the sheet is further facilitated and at the same time performed reliably.

When the work of removing the sheet P is completed, the exterior 3
When 6 is closed, the guide plate 45 is pushed by the projecting portion 46a of the guide plate 46, is rotated counterclockwise, and returns to the original position. During this closing operation, a protrusion (not shown) provided on the guide plate 46 side contacts the arm 63, and the arm 63 is rotated counterclockwise. Finally, as shown in FIG. 6, the lever 61 moves the guide plate 4
The sheet guide surface 5 is retracted.

In the second embodiment, like the auxiliary lever 60, the guide plate 45 is rotated by a rotating bias in association with the opening operation of the exterior 36. This promotes the effect of forming a large deflection a on the jammed sheet P as described above. However, the guide plate 45
6 can be fixedly held at the position shown in FIG. 6 and the auxiliary lever 60 can be rotated in association with the above-described opening operation of the exterior 36, the same effect as that of the first embodiment can be expected. Therefore, at least the auxiliary lever 60
It suffices that it is configured such that only one is rotated.

(Other Modes in Second Embodiment) Incidentally, even if each lever 61 of the auxiliary lever 60 is present at the position shown by the broken line when the exterior 36 is closed, it is described above. As described above, there has been no problem if the urging force of the spring 64 does not impose a large load on the conveyance of the sheet P and the conveyance of the sheet P is not hindered. That is,
With the sheet P being conveyed, the entire auxiliary lever 60 is rotated counterclockwise, and the sheet P can be guided and passed through the sheet conveying path 35.

Therefore, in order to restrict the lever 61 to the position of the broken line, an opening corresponding to the opening formed in the guide plate 45 is also provided on the guide plate 46 side, and the lever 61 is locked on the holding member 47a side. A member may be provided. Alternatively, without providing an opening on the side of the guide plate 46, the tip of the lever 61 may be brought into contact with the guide surface of the guide plate 46 so that the rotation thereof is restricted.

With such a structure, when the exterior 36 is opened, the rotation restricting state of the auxiliary lever 60 is such that the protrusion 6 and the arm 6 (not shown) provided on the guide plate 46 side are provided.
3 is released and released, and the lever 61 largely protrudes from the sheet guide surface on the guide 45 side similarly to the above-described action. As a result, the amount of flexure a due to the bending of the sheet P increases.

If a jam of the sheet P occurs and the sheet P remains in the sheet conveying path 35, the exterior 36
Is released. In conjunction with this opening operation, one guide plate 46 forming the sheet conveying path 35 is simultaneously opened. When the guide plate 46 is opened, the contact with the projecting portion 46a is released, and the regulation of the rotational biasing of the other guide plate 45 is released. Is rotated in the direction.

Therefore, the guide plate 45 and the lever 61 are
By the rotation of the sheet P, the sheet P retained in the sheet conveying path 35 is pushed in the opening direction, and a large bend a is formed as shown in FIG. Then, the sheet removing work can be easily performed by holding the portion of the flexure a.

When the sheet removing operation is completed, the exterior 36 is rotated counterclockwise to close the main body of the image forming apparatus 1. As a result, the projecting portion 46a of the guide plate 46 and the guide plate 45 are brought into contact with each other, and at the same time, the guide plate 45 is rotated counterclockwise and rotation is restricted to the state shown in FIG.

The guide plate 45 forming the sheet conveying path 35 in the above-described first and second embodiments is configured so as to be forcibly urged by the kick spring 48 in the clockwise direction in the drawing. There is. However, even if the kick spring 48 is not provided, since the sheet conveying path 35 is formed in the vertical direction, as shown in FIG.
5 is rotated clockwise, the guide plate 35
By providing the shaft portion 45a in the lower left portion of the, the rotational biasing force in the clockwise direction is generated by the weight of the guide plate 45 itself. As a result, the kick spring 48 can be eliminated, and the structure can be simplified. Even with such a configuration, the flexure a can be formed with respect to the sheet P as shown in FIG. However, when the sheet P is firmly adhered to the guide plate 45 by frictional charging or the like, it is effective to provide the kick spring 48 to forcibly rotate and urge the guide 45.

Further, in the present invention, as the sheet conveying path 35 of the sheet conveying device, the conveying path from the registration roller 21 to the transfer position is described as an example. However, it is needless to say that the jam sheet can be easily removed by providing not only the sheet conveying path 35 but also the guide path 27 and the discharge path 31 so that the jam sheet can be easily removed. The embodiments of the invention can be applied as they are.

When the sheet conveying path 35 is opened, not only the guide plates 45 and 46 are opened, but also the transfer device 6 provided at the transfer position is similarly exposed.
It is opened so that it is more separated. With this configuration, the work of removing the sheet P is further simplified. That is, the open area of the sheet conveying path is widened, and the sheet can be removed more easily.

[0093]

As described above, according to the sheet conveying apparatus of the image forming apparatus of the present invention, when the sheet conveying path is opened to remove the jammed sheet, the sheet conveying path is formed so as to bend the sheet. The guide plate that is rotatably provided on the side of the image forming apparatus main body that forms the image is rotated, so that it is possible to reliably form the deflection, and even when the sheet comes into close contact with the guide plate due to friction or the like, The sheet can be easily removed. Furthermore, since the projections are provided on the guide plate that forms the sheet conveying path so as to ensure a certain interval, by restoring the original state after removing the jam, the rotation bias of the guide plate is regulated. Thus, the sheet conveyance path can be secured.

Further, when the sheet conveying path is provided in the vertical direction, it becomes possible to rotate the guide plate by utilizing the own weight of the guide plate itself, and thus the biasing member. It is not necessary to provide, and the configuration becomes simple.

Further, by providing an auxiliary lever or the like for further projecting from the sheet guide surface of the guide plate when the sheet conveying path is opened, it is possible to form the amount of bending of the sheet staying in the sheet conveying path, and at the same time. If the guide plate side is also rotated, the amount of bending can be increased and the jam sheet removing operation can be further facilitated.

[Brief description of drawings]

FIG. 1 is a side view showing an example of a first embodiment constituting a sheet conveying device of an image forming apparatus according to the present invention.

FIG. 2 is an enlarged view showing a state in which the exterior of the image forming apparatus is opened in order to explain an operation of removing a jammed sheet in the sheet conveying apparatus in FIG.

FIG. 3 is a configuration diagram for explaining a schematic structure of an entire image forming apparatus including a sheet conveying device according to the present invention.

FIG. 4 is a diagram showing an example of a configuration in which the image forming apparatus of FIG. 3 is opened along a sheet conveyance path that constitutes the sheet conveying apparatus of the present invention.

5A and 5B are diagrams showing a configuration example of one guide plate for forming a sheet conveying path, FIG. 5A is a perspective view, and FIG.
Is a side view.

FIG. 6 is a side view showing a main part of a sheet conveying path for explaining a second embodiment of the sheet conveying device of the image forming apparatus according to the present invention.

7 is an auxiliary lever 6 that constitutes the sheet conveying apparatus of FIG.
It is a perspective view which shows an example of a 0 structure.

[Explanation of symbols]

1 Image forming device 2 photoconductor 5 Development device 6 Transfer device (transfer unit) 21 Registration roller 22 sheet feeder 35 sheet transport path 36 Exterior of image forming apparatus 40 lock mechanism 43 Lock release lever 45 (Second) guide plate 46 (First) guide plate 46a protrusion 47 holding member 48 Kick spring (biasing member) 49 Control pin 60 Auxiliary lever 61 lever

─────────────────────────────────────────────────── ─── Continuation of the front page (58) Fields surveyed (Int.Cl. ⁷ , DB name) B65H 5/38 G03G 15/00 518 G03G 21/16

Claims (3)

(57) [Claims] 1. A sheet conveying apparatus for conveying a sheet to an image forming position and discharging the sheet to the outside of the image forming apparatus after image formation, wherein a sheet conveying path is openable to facilitate removal of jammed sheets. In the sheet conveying device of the image forming apparatus, the one first guide plate forming the sheet conveying path is opened in association with the opening operation of the exterior, and the other second guide plate is rotatable. Further, it is provided on the first guide plate side in a rotating state, and the second guide plate is simultaneously rotated to the sheet conveying path side in association with the opening operation of the first guide plate. A protrusion is provided in a region of the first guide plate or the second guide plate that is not involved in guiding the sheet, and a first positioning member provided on the first guide plate side, Abut on the image A second positioning member provided on the image forming apparatus side is provided, and the projecting portion does not participate in positioning the exterior,
A sheet conveying device for an image forming apparatus, wherein the positioning member regulates the rotation of the guide plate and the positioning member compensates for the positional relationship between the image forming apparatus and the first guide plate. 2. The projecting portion, when returning the first guide plate to its original position, contacts the first guide plate or the second guide plate and rotates the second guide plate. After the second guide plate is returned, the sheet conveying path formed by both guide plates can be secured, and the rotation of the second guide plate is restricted. The sheet conveying device of the image forming apparatus according to claim 1. 3. The sheet conveying path is formed in a vertical direction, the second guide plate side is provided so as to be rotated to the first guide plate side by its own weight, and is related to the opening operation of the first guide plate. The sheet conveying device of the image forming apparatus according to claim 1, wherein the second guide plate is rotated by its own weight.