JP2003081478A - Sheet carrying device and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet carrying device in a compact figure by reducing the number of cleaning means when cleaning a plurality of sheet carrying roller surfaces. SOLUTION: A cleaning roller 1 for removing paper dust deposited on a roller 37a on the drive side of a delivery roller 37 for further delivering sheets fed by a sheet feed roller 34 are provided in contact with contact portions 2, 3 so as to be bridged between the rollers 34, 37a. The cleaning roller 1 is rotatably supported for cleaning the roller surfaces when driven to be rotated by the rotation of the feed roller 34 and the roller 37a. The cleaning roller 1 is used for cleaning the feed roller 34 and the roller 37a as plural rollers to be cleaned at the same time, helping forming a compact figure.

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 provided in an image forming apparatus or the like for feeding a sheet to a target position, and an image forming apparatus provided with the sheet conveying device, and more particularly to a sheet conveying device. Relates to a cleaning mechanism of the roller.

[0002]

2. Description of the Related Art Conventionally, an image forming apparatus forms a visible image on a sheet in response to an image forming start command.
A sheet conveying device is provided that is configured to feed a sheet held at a predetermined position to an image forming position. The sheet conveying device is not limited to such an image forming apparatus, but it is a rotation for conveying the sheet in a state of being pinched or pressed against the sheet in order to convey the sheet to a target position. It is configured by appropriately arranging a plurality of driven rollers.

The above-mentioned roller maintains a good friction state with the sheet, that is, stabilizes the feeding operation without slipping, and enables good conveyance. for that reason,
The roller itself is made of a material such as rubber having a high coefficient of friction in a roll shape and is fixed to the rotary shaft. If the surface of the roller is changed, the stability of the sheet conveyance is lost, the accurate conveyance cannot be performed, or the conveyance becomes defective, particularly, the sheet cannot be conveyed.

For such a roller, the sheet to be conveyed often contains additives such as talc and kaolin containing a silicon dioxide (SiO ₂ ) component in the manufacturing process. These additives, when the pulp content in the sheet is made into paper, so that the pulp content can be sufficiently agitated on one surface of the sheet,
Further, it is mixed so as to easily scoop up the pulp content and further improve the chromaticity of the finished sheet.

When such a sheet is used and the sheet is conveyed by using the roller which constitutes the above-mentioned sheet conveying device, the sheet is rubbed by the roller, the additive adhering to the sheet is separated from the sheet, and the roller is conveyed. Adhere to the surface.
This phenomenon is called "roller paper dust accumulation", and when paper dust adheres to the roller, it slips between the rollers and causes a reduction in the sheet conveying force by the roller. Therefore, accurate transportation cannot be performed, which may cause a jam in the transportation path. This is because when the sheet is conveyed by the roller, the frictional force between the roller and the sheet is reduced by "paper dust accumulation on the roller".

Further, in the electrophotographic image forming apparatus instead of the roller, when the paper powder adheres to the photosensitive member as the image bearing member, the paper is placed in the developing tank of the developing device arranged on the outer peripheral portion of the photosensitive member. Powder may be collected. As a result, the charging characteristics of the developer in the developing tank are disturbed, and the image quality is deteriorated due to uneven image forming density.

For this reason, conventionally, there has been disclosed a technique in which a cleaning means is provided for a roller which constitutes a sheet conveying device so as to remove paper dust and the like so that stable sheet conveyance can be always performed. It is proposed in Japanese Patent Publication No. In the technique disclosed in this publication, cleaning means for cleaning the roller surface is provided in pressure contact. As the cleaning means, a cleaning blade that fixes one end side and presses the free end side against the roller surface,
Alternatively, a cleaning brush, a cleaning roller having a rotatable roller structure, and the like have been proposed.

[0008]

By providing the cleaning means having the above structure, it becomes possible to remove the paper dust or the like adhering to the surface of the roller that is carrying the sheet, stabilize the sheet carrying force, and accurately carry the sheet. Like

However, when the cleaning means as described above is provided, it is necessary to provide the cleaning means for each roller. That is, it is used as a paper feed pickup roller that separates and conveys sheets from a stacked sheet bundle, a conveyance roller, a charging roller that charges a photoconductor in an electrophotographic image forming apparatus, and a fixing roller that fixes a toner image. On the other hand, it is necessary to provide cleaning means for each.

Therefore, by providing the cleaning means and the like respectively, not only the structure itself becomes complicated, but also a space therefor is required, which not only enlarges the sheet conveying device but also enlarges the entire image forming apparatus, It will be a big one.

In addition to the cleaning means, it is necessary to provide an accommodating section for collecting and accommodating the removed paper dust in correspondence with each cleaning means. Therefore, such a collecting unit also needs to be provided corresponding to each cleaning unit, so that the number thereof increases, and as described above, the sheet conveying apparatus and the image forming apparatus as a whole tend to be large.

[0012] The first object of the present invention is to solve the above-mentioned problems.

That is, an object of the present invention is to simplify the structure of the cleaning means provided for the rollers constituting the sheet conveying apparatus.

In particular, the present invention has an object to cause a cleaning action on a plurality of rollers by a cleaning means.

It is another object of the present invention to make the cleaning means compact, to make the construction of the sheet conveying device large, and to prevent the image forming apparatus from becoming large.

[0016]

The outline of the sheet conveying apparatus of the present invention for achieving the above-mentioned object will be described with reference to FIG. 1. For example, the surface of at least two different rollers (34, 37a) adjacent to each other. A cleaning means (1) is provided so as to be in contact with. With such a configuration, the roller surface can be cleaned by one cleaning unit for at least two rollers.

Since the cleaning means is provided on the roller surfaces adjacent to each other, the cleaning means can be arranged in the space between them, so that it is possible to prevent the entire sheet conveying apparatus from becoming large, and to equip the image forming apparatus. As a result, it is possible to avoid increasing the size of the entire apparatus without requiring a large-scale mechanism.

Further, if the cleaning means is rotatably provided as a roller structure, the cleaning means is driven by the rotation of a plurality of adjacent rollers, so that cleaning can be performed without providing a separate rotation drive mechanism. In this case, if the portion that contacts the plurality of rollers is formed of a brush, the cleaning efficiency can be improved. Further, the cleaning effect is promoted without increasing the contact pressure between the brush and the plurality of rollers, and the durability of the plurality of cleanings can be improved, that is, the life can be extended.

Further, the cleaning means is provided with a coiled spring and a spiral screw rotatably in one direction, so that the adhered matters such as paper dust removed from the surfaces of the plurality of rollers are collected in one place. Can be collected. In this case, the cleaning means can also be used as a means for collecting in one place. Moreover, by setting the collection point to a predetermined point, the structure for collecting each collection point to one specified location becomes simpler. Also in this configuration, the contact area with a plurality of rollers is suppressed,
The durability can be improved.

If a biasing means (6) is provided to the cleaning means as shown in FIG. 3 and the cleaning means (1) is brought into pressure contact with a plurality of rollers,
Since the play of the shafts of the plurality of rollers and the displacement of the positional relationship with the cleaning means are effectively absorbed and the rollers are appropriately pressed against the plurality of rollers, a cleaning effect can be expected. Therefore, it is possible to prevent excessive pressure from being applied to the shafts of the plurality of rollers and the cleaning means, and it is possible to improve the durability of the rollers.

Further, the cleaning means is provided so as to be movable in the direction of contacting with and separating from the plurality of rollers, and is controlled so as to come into contact with and separate from the plurality of rollers as needed.
When the operation of the sheet conveying device is stopped, it is possible to prevent the cleaning unit from being constantly pressed against the plurality of rollers, and by constantly being pressed, it is possible to prevent the defective conveyance of the sheet due to the deformation of the roller surface. Can contribute to improvement.

Here, by providing the image forming apparatus with the sheet conveying apparatus having the above-described structure, stable sheet conveying can be performed when the sheet is fed to a target position, and image formation due to defective sheet conveying can be performed. Defects can be prevented. In addition, waste of sheets due to defective sheet conveyance can be eliminated.

In a preferred embodiment of the image forming apparatus provided with this sheet conveying device, the cleaning means responds to the feeding of the sheet by contacting / separating the plurality of rollers for feeding the sheet. It is to be. Therefore, as shown in FIG. 3, the releasing means (8) for separating the cleaning means (1) in contact with the plurality of rollers.
In addition to the above, the control means for operating the releasing means is provided to control the cleaning means so that the cleaning means can be freely contacted and separated. With this configuration, for example, when the sheet is fed in response to the start of image formation, the cleaning unit is brought into contact with the plurality of rollers. This cleans the surface of multiple rollers,
The sheet feeding is stable, and the effect of preventing feeding failure is enhanced. That is, the cleaning means contacts a plurality of rollers to be cleaned such as a paper feed roller during image formation, and is separated during other non-image formation.

Further, in the contact / separation control of the cleaning means, not only the response to the starting operation but also the predetermined number of sheets determined for the number of fed sheets, and the fixed time in response to the power-on time, the cleaning is performed. Hope the effect,
The sheet feeding can be stabilized. in this way,
By realizing the contact / separation control of the cleaning means, it is possible to avoid constant pressure contact with the plurality of rollers, prevent deterioration of durability due to deformation of the rollers, and expect stable sheet conveyance at all times.

As described above, according to the sheet conveying apparatus of the present invention, it is possible to simultaneously clean the surfaces of a plurality of rollers by the cleaning means, it is possible to prevent the size of the whole from becoming large, and it is possible to achieve compactness and at the same time to make an image forming apparatus. By being provided, the space can be effectively used and the entire apparatus can be made compact.

[0026]

BEST MODE FOR CARRYING OUT THE INVENTION A sheet conveying apparatus of the present invention will be described below by taking the configuration of a sheet conveying apparatus provided in an image forming apparatus as an example.

First, the overall construction of an electrophotographic image forming apparatus having a sheet conveying device will be described with reference to the construction shown in FIG. In FIG. 2, the image forming apparatus includes a document reading unit 1
0, an image forming unit 20, a sheet feeding unit 30, and a sheet conveying unit 40 including sheet discharge.

The document reading section 10 has a document table 11 made of transparent glass or the like on the upper part thereof, and an optical scanner 12 formed by scanning the document placed on the document table under the document table 11 with an optical system. Are arranged. The optical scanner 12 includes a lamp 13 that illuminates and exposes a document, and a plurality of reflectors 14 and 1 that appropriately reflect light reflected from the document to form a desired optical path.
5, 16 are read-out elements (CCD) 17 which are arranged at the image-forming position at the end of the optical path, receive reflected light from the document and electrically convert the optical image of the document, and are arranged in the optical path. An image forming lens 18 for forming an image of reflected light from the original on the CCD 17 is provided.

The lamp 13 and the reflecting plate 14 are integrally supported by the first supporting portion and run parallel to the document table 11 from the left to the right in the drawing, so that the lamp 13 is used for the document. The original document on the table 11 is optically scanned while being exposed.
The reflectors 15 and 16 are integrally supported by the second supporting portion and travel in the same direction as the first supporting portion, and the traveling speed thereof is set to 1/2 of the first traveling speed. Scan optically. As a result, the image of the original is sequentially formed on the CCD 17 line by line, converted into an electric signal corresponding to the density of the image, and the image of the original can be read digitally.

The image signal read by the document reading section 10, that is, image data is sent to the lower image forming section 20 and a visible image corresponding to the image data is formed on the sheet. The image forming unit 20 receives the image data, performs image processing on the image-forming data, and then supplies the image-forming data to a laser scanning unit (LSU) (not shown).
The surface of the drum-shaped photoconductor 21 uniformly charged with laser light is irradiated. The LSD drives the laser ON-OFF according to the image data, and irradiates the surface of the photoconductor 21 with an optical image by the laser beam light.

The photoconductor 21 is rotated in the direction of the arrow by the image forming operation, and is charged to a potential of a polarity determined by the charger 22 before being irradiated with the laser beam. A developing device 23 is provided opposite to the position after the irradiation of the laser light to attach the colored toner to the electrostatic latent image formed on the surface by the laser irradiation. Next, the photoconductor 21
The process arranged to face is the transfer device 24. The transfer device 24 charges the back surface of the sheet, which will be described later, and transfers the toner image formed on the surface of the photoconductor 21.

A static eliminator 25 and a cleaning device (not shown) are provided to face the photoconductor 21 passing through the transfer device 24 so as to clean the surface of the photoconductor in preparation for the next image formation. There is. Here, the transfer device 24
The sheet passing through the sheet is separated from the surface of the photoconductor 21 after the transfer, and the fixing device 2 is provided to fix the transferred toner image.
It is sent to 6.

The fixing device 26 includes a heat roller which is heated and controlled to a fixing temperature for melting and fixing the toner.
It is composed of a pressure-contact roller which is brought into pressure contact with the roller, and holds the sheet with an appropriate pressure, and conveys the sheet while fixing the toner image.

The above-described structure is the image forming section 20, and the sheet feeding section 30 for feeding the sheet to the image forming section.
A sheet conveying unit 40 is further provided for further feeding the fed sheet to a target position in order to relay between the sheet and the sheet.

The sheet conveying section 40 is provided to feed the sheet fed from the sheet feeding section 30 to a transfer position facing the transfer unit 24 which is the image forming position of the image forming section 20, and after the transfer is completed. The sheet that has passed through the fixing device 26 is sent to the sheet discharge unit, or is stopped while the sheet is being sent and is sent back to the image forming position via the re-feed path. .

The present invention relates to a sheet conveying device including the sheet feeding section 30 and the sheet conveying section 40, and these constitute a sheet conveying apparatus.

First, the structure of the sheet feeding section 30 will be described. An automatic sheet feeding section 31 and a manual sheet feeding section 32 are provided. The automatic paper feed unit 31 includes a tray or a cassette 33 that accommodates a large number of sheets P, and a paper feed roller (pickup roller) arranged corresponding to the leading edge of the sheet P.
34 is provided. Then, the manual paper feeding unit 3
2 has a paper feed roller 36 corresponding to a tray 35 on which one or more sheets are placed. Further, sending rollers 37 and 38 are provided corresponding to the sheet feeding rollers 34 and 36 to send the sheet to the above-described sheet conveying unit 40.

In the automatic paper feeding unit 31, the accommodated sheets are pushed up to the paper feeding roller 34 side during the paper feeding operation and pressed against each other, and the uppermost sheet is rotated by the rotation of the paper feeding roller 34. The sheet P is fed. Then, the sheet may be conveyed to the conveying roller 37 and the sheet may be conveyed by the conveying roller 37, so that the accommodated sheet is lowered and the pressure contact with the sheet feeding roller 34 is released.

Also in the manual paper feed section 32, the tray 35 can be moved up and down, and in response to the paper feeding operation, it pushes the sheet placed on the tray 35 against the paper feeding roller 36 under pressure. When the sheet is raised and the sheet feeding operation is completed (a state where the sheet P is conveyed by the conveying roller 38), the sheet is lowered and the pressure contact between the sheet (or tray) and the sheet feeding roller 36 is released.

As described above, the sheet is fed by the paper feed roller 34.
Alternatively, the sheet is fed by 36 or is fed by the feeding roller 37 or 38, and is fed to the sheet feeding section 40.

The sheet conveying section 40 is provided with a registration roller 41 for temporarily stopping the leading edge of the sheet. This registration roller 41 is, for example, each of the delivery rollers 37, 3
8 is provided at the confluence of the sheets conveyed from 8, and the sheet conveyance start control is performed in synchronization with the timing when the toner image formed on the photoconductor 21 reaches the transfer position.

When the leading edge of the sheet conveyed through the registration rollers 41 reaches the transfer position, it coincides with the leading edge of the toner image formed on the surface of the photoconductor 21, and the transfer device 24 acts to transfer the toner. The image is electrostatically transferred. Then, by passing through the transfer position, the toner image is peeled off from the photoconductor 21 and sent to the fixing device 26, and the unfixed toner image after transfer is fixed. The sheet passing through the fixing device 26 passes through the discharge path 42, and when the image formation is completed, the sheet discharge unit 44 directly passes through the discharge roller 43.
It is processed to be discharged.

On the other hand, in the case of performing double-sided copying on a sheet, the trailing edge of the sheet is detected in front of the ejection roller 43 while the sheet is being ejected by the ejection roller 43, and the sheet is ejected at this point. The roller 43 is driven in the direction opposite to the rotation direction during the discharging process. As a result, the sheet on which the image is formed on one surface is reversed (switchback conveyed) in the conveying direction and is sent to the re-conveying path 45 continuing to the discharge path 42. The re-conveyance path 45 is provided so as to branch to the discharge path 42 toward the discharge roller 43, and is formed to communicate with the registration roller 41 described above. Therefore, the front and back of the sheet are reversed by passing through the re-conveyance path 45, and the conveyance is controlled again via the registration rollers 41. As a result, an image can be formed on the sheet surface opposite to the previous image forming surface,
Images can be formed on both sides.

A plurality of return rollers 46, 47, 48 for feeding the sheet to the registration roller 41 are arranged in the re-conveyance path 45.

(Preferred Embodiment of Sheet Conveying Apparatus of the Present Invention) In the image forming apparatus having the above-described structure, the sheet conveying apparatus is provided for feeding the sheet to a target position. That is, a sheet conveying device is provided so that a sheet is fed, the fed sheet is transferred to a transfer position, and after the sheet is transferred, the sheet is conveyed to a discharge portion or the sheet is reversed and conveyed to the transfer position again. Particularly, in the sheet conveying device of the present invention, the sheet feeding unit 30 and the sheet conveying unit 4
The configuration includes 0. Further, in the electrophotographic image forming apparatus, the fixing device 26 also constitutes a part of the sheet conveying device and is arranged in the sheet conveying path.

Therefore, in the above-described sheet conveying apparatus, the structure can be applied to all portions including rollers for conveying (or feeding) sheets, which will be described in detail below.

In the description of the embodiment of the present invention, the paper feed roller 34 and the feed roller 37 in the automatic paper feed unit 31 will be described below, but the present invention is not limited to this, and the manual paper feed unit 32 is not limited thereto. The present invention is also applicable to the case where the paper feed roller 36 and the delivery roller 38 are used, and when the transfer device 24 is composed of a transfer roller, the transfer roller and the fixing device 26, the transfer roller and the registration roller. 41, or the configuration in which the transport rollers 46, 47, 48, etc. are targeted.

Therefore, as described above, FIG. 1 shows in detail the configuration of the sheet conveying apparatus including the sheet feeding roller 34 and the conveying roller 37 to which the present invention is applied. In this figure,
The configuration of the sheet conveying device will be described in detail.

FIG. 1 shows the automatic paper feeder 3 as described above.
1 shows in detail the configuration of No. 1 and includes a cassette or tray 33 that accommodates a large number of sheets P. In the cassette 33, a loading plate 33A that holds a sheet and can move up and down is provided, and the loaded sheet is pushed upward from the lower part, and the sheet feeding roller 34 is arranged opposite to the sheet feeding roller 34.
I'm trying to make pressure contact with.

In the cassette 33, the separation claws 33 are provided at both ends of the accommodated sheet P at the leading end in the sheet feeding direction.
B and the like are provided. This separating claw has a well-known structure. When the uppermost sheet is fed by the rotation of the sheet feeding roller 34, the sheet bends (curves) when passing over the separating claw at both corners, and is separated from the next sheet. The sheet is fed by one sheet feeding operation.

Therefore, when the paper feed roller 34 is rotated, it is possible to realize and feed one sheet of the uppermost pressed sheet P. The fed sheet P is conveyed to the delivery roller 37 located on the downstream side in the sheet conveying direction. Sheet P conveyed by the delivery roller 37
Are fed to the registration rollers 41 in the same manner as the sheets fed from the manual feed unit 32 as described above.

The feeding roller 37 is composed of a pair of rollers, and is formed of a member having a high frictional resistance such as rubber for conveying the sheet, and is rotatably driven.
7a and a roller 37 which is pressed against the roller and driven to rotate.
b and.

The paper feed roller 34 and the delivery roller 37
Is configured as a member having a high frictional resistance as described above in order to press and contact the sheet to stably feed and convey the sheet. In particular, the driving side roller 37a of the delivery roller 37 is
Like the paper feed roller 34, it is formed of a member such as rubber. Therefore, when the sheet is conveyed, paper dust or the like is easily attached.

In the present invention, the cleaning roller 1 as a cleaning means is configured so as to bridge between a plurality of rollers arranged adjacent to each other, that is, the paper feed roller 34 and the drive side roller 37a of the delivery roller 37. Is provided. As shown in FIG. 1, the rollers 34 and 37 contacting the cleaning roller 1 are rotated in the same direction. In the meantime, the cleaning roller 1 of the present invention is arranged.

Further, the cleaning roller 1 of the present invention is rotatably supported without a drive mechanism itself.
The cleaning roller 1 is, for example, a high-friction member or an adhesive member for cleaning (cleaning) dirt such as paper dust attached to the paper feed roller 34 and the delivery roller 37 (driving side roller 37a). It is also effective to configure with.

The cleaning roller 1 is provided so as to come into pressure contact with the paper feed roller 34 and the delivery roller 37 (driving side roller 37a) at the contact portions 2 and 3, respectively. Therefore, the rollers 34 and 37, which are the rollers to be cleaned, are driven to rotate.

Here, the cleaning roller 1 according to the present invention is not required to be composed of the high friction member or the like as described above, and a sufficient cleaning effect can be expected for the following reasons. That is, the paper feed roller 34 that is driven to rotate in the same direction and the delivery roller 37 (the drive side roller 37
A cleaning effect on the surfaces of both rollers can be expected by rotatably supporting it with (a), bridging between them, and pressing them.

First, paying attention to the paper feed roller 34, the cleaning roller 1 is pressed to form a concave portion at the position of the contact portion 2 of the paper feed roller 34. The concave portion of the contact portion 2 is sequentially moved by the rotation of the paper feed roller 34. That is, the outer peripheral surface of the paper feed roller 34 is the cleaning roller 1
It is due to the fact that the parts that have been pressed against each other move in sequence. The same is true on the side of the delivery roller 37, and a concave portion is formed in the contact portion 3 that comes into pressure contact with the cleaning roller 1, and this concave portion is sequentially moved by rotation.

By focusing on a part of the surface of the paper feed roller 34 and the delivery roller 37 (driving side roller 37a) by the above-mentioned rotation, that part approaches the cleaning roller 32 with the rotation, and accordingly. The pressure received from the cleaning roller 1 also gradually increases. As a result, the contact portions 2 and 3 form a recess. A high pressure is maintained while being pressed against the cleaning roller 1. After that, when a part of the pressure passes through the cleaning roller 1, that is, when the pressure contact state with the cleaning roller 1 is released, the pressure acting on the cleaning roller 1 sharply decreases. As a result, a so-called ironing action occurs on the paper feed roller 34 and the delivery roller 37 (driving side roller 37a), and the paper dust and the like adhering to the surface thereof is removed and cleaned.

From the above structure and operation, the mechanism for rotating the cleaning roller 1 is not required, and the structure is simplified. In other words, it is desirable that the cleaning roller 1 be driven to rotate by the rotation of the pressure-feeding paper feed roller 34 and the delivery roller 37 (driving side roller 37a), and it is not necessary to use a separate drive source and the cost is reduced. Also, the rotation load and the like can be reduced.

Further, in the above-described embodiment of the sheet conveying apparatus of the present invention, the cleaning roller 1 as the cleaning means is provided between the paper feeding roller 34 and the sending roller 37 (driving side roller 37a). ing. The number of rollers to be cleaned applied to this one cleaning roller 1 is two. However, it is not limited to such a number, and can be applied to a case where the number exceeds two. This is a single cleaning roller 1 including the sheet feeding roller 34, the feeding roller 37 (driving side roller 37a), and the registration roller 41 in the sheet conveying apparatus described in the present invention.
It is also possible to make it contact with.

For example, the cleaning roller 1 is arranged so as to be in contact with each adjacent cleaning target roller, and is arranged in consideration of the diameter of the cleaning roller 1 and the arrangement interval of each cleaning target roller. Only one cleaning roller 50 can clean two or three or more cleaning target rollers.

For this reason, when the cleaning means is required for the rollers that constitute the sheet conveying device and feed and convey the sheets, the required cleaning means can be minimized, that is, the number can be reduced. This makes it possible to simplify the structure of the sheet conveying device and make it compact,
By directly applying it to the image forming apparatus, it is possible to avoid making the entire apparatus large and to make it compact.

(Supporting structure of the cleaning means of the present invention)
The cleaning roller 1 which is the cleaning means provided in the sheet conveying apparatus of the present invention is rotatably supported as described above. An example of the supporting structure will be described below.

As shown in FIG. 3, the cleaning roller 1 has, for example, a paper feed roller 34 and a delivery roller 37 (driving side roller 37) on a rotary shaft 1A for rotatably supporting the cleaning roller 1.
A cleaning unit 1B made of rubber or the like is provided for contacting with a) and performing a cleaning process. Also, the rotating shaft 1A
The cleaning unit 1B and the cleaning unit 1B may be integrally molded by the same member. In such a case, the cleaning roller can be integrally molded with a hard member (for example, hard resin or metal).

Both ends of the rotary shaft 1A have the paper feed roller 34 and the feed roller 37 (driving side roller 37).
a) is rotatably supported by bearings 5 on the same support frame 4 on both sides, which is rotatably supported. The bearing 5 rotatably supports at least the rotary shaft 1A and is movable in the direction in which the cleaning roller 1 is pressed against the paper feed roller 34 and the delivery roller 37 (driving side roller 37a). Like to support. That is,
The cleaning roller 1 is movably supported by the bearing 5 in a range of a position in contact with the paper feed roller 34 and the delivery roller 37 (a roller 37a on the driving side) and a position apart from the contact.

A pressure spring (spring) 6 is attached to the support frame 4 so that the rotary shaft 1A is pressed against the paper feed roller 34 and the delivery roller 37 (driving side roller 37a).
Is provided.

In the supporting structure as described above, the cleaning roller 1 includes the paper feed roller 34 and the delivery roller 37.
The roller 37a on the driving side is appropriately pressed by the action of the pressure spring 6. As a result, the cleaning roller 1 is brought into pressure contact with the paper feed roller 34 and the delivery roller 37 (driving side roller 37a), so that cleaning can be performed more effectively.

The pressure spring 6 is provided in the paper feed roller 34.
And a biasing means for bringing the cleaning roller 1 into pressure contact with the delivery roller 37 (driving side roller 37a). Therefore, it is possible to absorb the play of the shafts of the paper feed roller 34 and the delivery roller 37 (driving side roller 37a) that the cleaning roller 1 presses. Therefore, it is possible to prevent excessive pressure from being applied to each of the rollers to be cleaned, improve the durability of each roller, and at the same time expect a stable cleaning action.

Further, as the portion for rotatably supporting the cleaning roller 1, the same supporting frame 4 as the paper feeding roller 34 and the sending roller 37 (driving side roller 37a) can be used, so that There is no need to provide a dedicated support frame, etc., and it is possible to make it compact.

According to the structure shown in FIG. 3, the cleaning roller 1 is located at the lower part, that is, at the lower position in the direction of gravity.
A recovery unit 7 for receiving the removed paper dust and the like is provided correspondingly. Although the recovery unit 7 is illustrated as being provided on the one end side of the rotary shaft 1A, it is suitable when, for example, the adhered matter such as the removed paper dust is conveyed in the direction of the rotary shaft 1A. . However, when the adhered matter such as the removed paper dust falls as it is, in FIG.
You may make it arrange | position the collection | recovery part 7 along the direction along the whole length of a longitudinal direction.

(Preferred Embodiment Applied to Image Forming Apparatus) A preferred embodiment in which the sheet conveying apparatus of the present invention is applied to the image forming apparatus as shown in FIG. 2 will be described with reference to FIG. That is, the cleaning means is pressed against the cleaning target roller provided for the purpose of sheet conveyance.

The state in which the cleaning roller 1, which is a cleaning means, is constantly in pressure contact with the paper feed roller 34 or the like is maintained while the paper feed roller 34 is not rotating, such as during standby. As described above, the abutting portions 2 and 3 where the rollers abut each other form a concave portion, and if the state is maintained for a long time, the paper feeding roller 34 is deformed and the concave portion does not return to the original shape. I'm afraid.

As a result, the service life of the paper feed roller 34, the delivery roller 37, etc. becomes shorter than the normal time, and replacement or the like is required in a short period of time. A preferred embodiment aiming at solving such a problem will be described below. As a result, it is possible to constantly stabilize the feeding of the sheet by the sheet feeding roller or the like.

Therefore, in the structure of FIG. 3, the rotary shaft 1A is moved against the urging force of the pressure spring 7, and the cleaning roller 1, the paper feed roller 34, and the feed roller 37 are moved.
A solenoid 8 which constitutes a releasing means for releasing the contact state, that is, the contact state with the (drive side roller 37a), that is, the contact state, is provided so as to be connected to the rotating shaft 1A. For example, when the solenoid 8 is energized (ON), the pressure spring 6 causes the cleaning roller 1 to come into pressure contact with the paper feed roller 34 and the delivery roller 37 (driving side roller 37a). In the non-energized (OFF) state, the cleaning roller 1 is configured to be separated from the paper feed roller 34 and the delivery roller 37 (driving side roller 37a) against the biasing force of the pressure spring 6. .

Therefore, one embodiment of a suitable control means by controlling the solenoid 8 will be described below with reference to FIG. The control means for controlling the solenoid 8 is a control means provided in the main body of the image forming apparatus as shown in FIG. 2, and controls the image forming operation in association with it.

First, one embodiment will be described below. When the main body of the image forming apparatus is in the standby state, the solenoid 8 is de-energized by the control means, whereby the cleaning roller 1, the sheet feeding roller 34, and the feeding roller 37 (driving side roller 37a) are separated from each other. Has been maintained.

Therefore, a print request in the image forming apparatus,
That is, when a print request (image forming request) for printing the image data read by the outside or the scanner unit 12 is made (S1), the solenoid 8 is energized (S2).
As a result, the action of the pressure spring 6 causes the cleaning roller 1 to move the cleaning roller 1 to the paper feed roller 34 and the delivery roller 37.
It is brought into pressure contact with (the driving side roller 37a). Then, a start process (S3) for feeding and conveying the sheet P and reading by the scanner unit 12 is performed.

By the start of this image forming process, the paper feed roller 34 and the delivery roller 37 (driving side roller 37a)
Is rotated, the cleaning process by the cleaning roller 1 that comes into contact therewith is realized.

Then, the existence of the next print processing operation is confirmed (S4), and if there is the continuous print processing, the processing in step S3 is sequentially executed. As a result, the surfaces of the sheet feed roller 34 and the delivery roller 37 (driving side roller 37a) are cleaned, and the sheet P can be stably fed at all times. The sheet P passes through the sending roller 37, and further the registration roller 41.
It is sent to the image forming position via. It is possible to suppress the sheet conveyance failure in the sheet conveyance as described above, and always realize stable sheet feeding.

In the confirmation of the continuation of the printing process, when the continuation is not continued, the solenoid 8 is de-energized (OFF). As a result, the pressure spring 6
Against the biasing force of the cleaning roller 1, the cleaning roller 1 is fed to the paper feed roller 34 and the delivery roller 37 (driving side roller 37a).
It is further separated (S5), and the image forming apparatus main body is on standby for the next printing process.

In the above process, the cleaning roller 1 is brought into contact with the paper feed roller 34 and the delivery roller 37 (driving side roller 37a) when the printing process is started, and is placed in the other standby state. Are separated. In other words, in this embodiment, the cleaning roller 1 is brought into contact with the paper feed roller 34 or the like at the time of image formation, and is separated at the time of other non-image formation.

Therefore, it is possible to prevent the paper feed roller 34 and the delivery roller 37 (driving side roller 37a) from constantly being in pressure contact with each other and deforming the surface of the roller to cause defective feeding and conveyance. You can extend your life etc. Further, since the cleaning process is performed by starting the printing process, it is possible to always maintain a stable state and stabilize the sheet feeding.

The control means for controlling the energization of the solenoid 8 is adapted to execute the printing process. However, the present invention is not limited to this, and the feeding of the sheet P is performed when a predetermined number of sheets are executed. The cleaning process may be performed for a fixed time. According to such a configuration, it is possible to perform the process at each predetermined period without performing the print process frequently. As a result, the paper feed roller 34 and the delivery roller 3
It is possible to prevent unnecessary wear of the 7 (driving side roller 37a) in contact with the cleaning roller 1, reduce wear of the cleaning roller 1 and the like, and also improve durability of each roller.

Further, the control means may be arranged so that the cleaning process is executed when the power source of the image forming apparatus is turned on. That is, in order to use the image forming apparatus, the cleaning roller 1 is kept in contact with the paper feed roller 34 for a certain time when the power is turned on, and the cleaning process can be executed during the warm-up when the power is turned on. For that purpose as well, when the power is turned on, the cleaning roller such as the paper feed roller 34 and the delivery roller 37 is rotationally driven by the control means for a predetermined time.

According to such a structure, the cleaning process can be naturally performed during the warm-up at the time of turning on the power source, and after the warm-up is completed, the image forming operation can be started as it is, and at the same time, it is frequently pressed against the cleaning roller or the like. Therefore, the durability of the roller can be improved, and stable sheet conveyance can be expected.

The releasing means for making the cleaning roller 1 which is the cleaning means freely contactable and separable is not limited to the solenoid 8, but the cleaning roller 1 may be a rotating cam using a drive source such as a motor. The axis 1A may be moved. Further, although the configuration has been described in which the cleaning roller 1 is brought into contact with the paper feed roller 34 or the like against the pressure spring with the solenoid 8 turned on, the opposite, that is, by turning off the solenoid 8,
The pressure spring 8 may directly contact the paper feed roller 34 or the like. This may be designed appropriately.

In addition, in the structure for contacting and separating the cleaning roller 1 by the releasing means, it is not essential to provide the pressure spring 8, but the cleaning roller 1 is normally separated from the paper feed roller 34 and the delivery roller 37. It is also possible to configure so as to contact the paper feed roller 34 and the delivery roller 37 when the solenoid 8 as the releasing means is energized.

(Various Embodiments of Cleaning Means) According to the above-described sheet conveying apparatus of the present invention, the cleaning roller 1 has been described as an example of the cleaning means. Various embodiments of other cleaning means suitable for the present invention instead of such a cleaning means will be described below.

When the cleaning roller 1 is provided as the cleaning means, for example, the paper feed roller 34 and the delivery roller 37 (driving side roller 37a) are brought into pressure contact with each other. This can be expected to have a higher cleaning effect by increasing the contact area at the contact portions 2 and 3 (the contact portion is increased). Therefore, as described with reference to FIG. 3, by providing the pressure spring 8 and the like, an appropriate pressure contact state is maintained and the cleaning effect is enhanced.

Therefore, by increasing the contact pressure at the contact portions 2 and 3, the paper feed roller 34 and the delivery roller 3
7 (driving side roller 37a) and cleaning roller 1
There is still a problem in durability due to abrasion and the like. That is, if the pressure contact force is increased to enhance the cleaning effect, the wear tends to be accelerated. As a result, the cycle of replacement of each roller is shortened, durability is reduced, and life is shortened.

Therefore, the contact portion with the paper feed roller 34 and the delivery roller 37 (driving side roller 37a) can be enlarged to such an extent that the cleaning effect can be expected, and the cleaning effect can be sufficiently provided without increasing the pressure contact force. Expected implementations are described below.

In one embodiment, the cleaning means has a cleaning brush structure. The cleaning means of this cleaning brush configuration has a roller configuration on the outer periphery thereof, and can be configured by, for example, implanting brushes on a roll-shaped surface. Alternatively, a cleaning unit 1B provided with a brush having bristles implanted on the rotary shaft 1A may be wound in a spiral shape. A well-known structure can be used as it is as such a thing.

That is, in FIG. 1, the portions in contact with the paper feed roller 34 and the delivery roller 37 (driving side roller 37a) at the contact portions 2 and 3 may be brush-shaped and may be roller-shaped. . Hereinafter, this is called a roller brush.

The roller brush is rotatably supported by the supporting structure shown in FIG. 3 so that the roller brush is rotatably supported, and the paper feed roller 34 and the delivery roller 37 (driving side roller 37a).
And the brushes come into contact with each other at the positions of the contact portions 2, 3. As a result, the surfaces of the paper feed roller 34 and the delivery roller 37 (driving side roller 37a) can be cleaned with a brush.

In this case, the cleaning effect can be expected by the contact length of the brush without being influenced by the pressure contact force between the paper feed roller 34 and the delivery roller 37 (driving side roller 37a). Therefore, it is possible to suppress wear of the paper feed roller 34, the delivery roller 37 (driving side roller 37a), etc., and improve durability.

In the above roller brush configuration, the contact nip width (contact nip width) with the cleaning roller such as the paper feed roller 34 and the delivery roller 37 (driving side roller 37a) is determined based on the hardness of the brush and the length of the bristles. (Length, area, etc.) can be arbitrarily set, adjustment for that can be simplified, and the cleaning effect can be increased. Further, it is not necessary to provide the pressure spring 6 or the like, and the structure can be simplified.

Another embodiment of the cleaning means will be described with reference to FIG. FIG. 5 shows that the adhered substances such as paper dust removed by rotation can be conveyed in one direction and collected.

As shown in FIG. 5, the cleaning means is
The cleaning means of a coil spring structure is shown. Both ends of the coil spring 9 are rotatably supported. According to such a coil spring 9, as compared with the case where the outer peripheral surface of the cleaning roller 1 described above has a simple cylindrical shape, the coil spring 9 is different from the feed roller 34 and the delivery roller 37 (driving side roller 37a). Contact area,
Very small contact area. As a result, the paper feed roller 3
4 and the feed roller 37 (driving side roller 37a) and the like, the wear speed due to pressure contact with the cleaning roller can be slowed down, and the durability can be improved.

Moreover, in FIG. 5, when the coil spring 8 is driven and rotated in the A direction,
For example, the paper dust and the like removed from the paper feed roller 34 and the delivery roller 37 (driving side roller 37a) are conveyed in the direction of arrow B. Therefore, as shown in FIG. 3, it is possible to provide the collecting unit 7 for collecting the adhered substances such as paper powder on the one end side of the roller.

The cleaning means which can expect such actions and effects is not limited to the coil spring 9. For example, a groove is provided in a spiral shape (spiral shape) on the outer peripheral surface of the cleaning roller 1. Further, as the cleaning roller 1, a portion in contact with a cleaning target roller such as the sheet feeding roller 34 may have a spiral screw structure. With such a configuration, the contact area (contact portion) where the paper feed roller 34 and the delivery roller 37 (driving side roller 37a) come into contact with each other can be reduced, and the durability can be improved.

Moreover, as shown in FIG. 5, the adhered material that has been cleaned can be moved in the B direction with respect to the rotation in the A direction. As a result, the collecting unit 7 can be provided on the one end side of the roller, and the size reduction of the sheet conveying device can be further promoted.

Further, the collecting section 7 may be provided at one end, and a plurality of collecting sections provided corresponding to the respective cleaning means are connected to each other to simplify the structure of collecting all in one place.

[0104]

According to the sheet conveying apparatus of the present invention, the cleaning means is provided so as to come into contact with a plurality of rollers (cleaning rollers) for the purpose of feeding the adjacent sheets, so that each roller is individually attached. It is not necessary to provide a cleaning means in the above, and one cleaning means can clean the surface of a plurality of rollers to be cleaned.

As a result, the number of cleaning means can be reduced, the cost can be reduced, the sheet conveying device can be made compact, and the image forming device can be made compact by providing the sheet conveying device.

Further, the cleaning means is provided so as to be able to come into contact with and separate from the roller to be cleaned, if necessary.
It is possible to prevent deformation of the cleaning target roller due to useless contact, defective feeding, and the like, which makes it possible to prolong the service life and expect stable feeding of the sheet for a long period of time.

For example, the cleaning process can be performed at the time of image formation in the image forming apparatus, and by avoiding contact during standby, deformation of the roller to be cleaned and conveyance failure can be suppressed. In addition, the contact period can be shortened and an efficient cleaning process can be realized by bringing them into contact with or separated from each other when the power is turned on or the number of times of image formation, and it is possible to improve roller durability and stabilize sheet conveyance for a long period of time. Become.

Further, by providing a coil spring and a spiral member as the cleaning means, it is possible to reduce the contact portion with the roller to be cleaned, suppress the deterioration of durability due to wear, and collect the removed material in one direction. It becomes possible to eliminate the need to provide special means for that.

[Brief description of drawings]

FIG. 1 is a structural diagram showing a configuration example of a sheet conveying device for explaining a preferred embodiment including a cleaning unit of the present invention.

FIG. 2 is a diagram showing an overall configuration of an image forming apparatus including the sheet conveying device shown in FIG.

FIG. 3 is a cross-sectional view showing an example of a supporting structure of a cleaning unit according to the sheet conveying apparatus of the present invention.

FIG. 4 is a control flowchart showing an example of a control operation of a cleaning unit in the image forming apparatus including the sheet conveying apparatus of the present invention.

FIG. 5 is a perspective view showing another embodiment of the cleaning means of the present invention.

[Explanation of symbols]

1 Cleaning roller (cleaning means) 1A rotating shaft 1B cleaning section 2 contact area 3 contact part 4 Support frame 5 bearings 6 Pressure spring (biasing means) 7 Collection Department 8 solenoids 9 Coil spring (cleaning means) 31 Automatic paper feeder 32 Manual feed section 34 Paper feed roller (cleaning roller) 36 Paper Feed Roller (Cleaned Roller) 37 Sending roller (cleaning roller) 37a Drive side roller ((cleaning roller)) 38 Sending roller (cleaning roller) 41 Registration roller 46 Conveyor roller 47 Conveyor roller 48 transport rollers

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Shinji Oishi             22-22 Nagaikecho, Abeno-ku, Osaka-shi, Osaka             Inside the company F-term (reference) 2C061 AQ06 AR03 AS02 BB08 BB33                       CM07 CM13                 2H134 GA08 GB02 GB05 KA28 KB07                       KB08 KC01 KC03 KF02 KF03                       KG10 KH01 KH03 KH09 KH10                 3F101 AB01 AB06 AB07 LA01 LB03                 3F343 FA01 FB01 FC23 FC24 GA01                       GB01 GC01 GD01 JA01 JD03                       JD33 KB04 KB17

Claims (11)

[Claims] 1. A sheet conveying device comprising a plurality of rollers arranged to feed a sheet to a desired position, wherein a cleaning means is rotatable so as to come into contact with each of a plurality of rollers arranged adjacent to each other. A sheet conveying device characterized by being provided. 2. The sheet conveying apparatus according to claim 1, wherein the cleaning unit is provided in a roller shape and is rotated by rotation of a plurality of rollers. 3. The sheet conveying apparatus according to claim 2, wherein the roller-shaped cleaning unit has a brush-shaped portion in contact with the plurality of rollers. 4. The sheet conveying apparatus according to claim 1, wherein the cleaning unit is formed in a spiral shape. 5. The cleaning means is provided so as to be movable in a direction in which it comes into contact with or separate from the plurality of rollers, and is provided with a biasing means for biasing in a direction in which the plurality of rollers are pressed against each other. The sheet conveying apparatus according to claim 1, wherein the sheet conveying apparatus is a sheet conveying apparatus. 6. A releasing means for releasing the contact with a plurality of rollers by moving the cleaning means against the urging direction of the urging means, and the releasing means is controlled to control the releasing means as necessary. The sheet conveying device according to claim 5, further comprising: a control unit that controls the cleaning unit so that the cleaning unit can be moved toward and away from the plurality of rollers. 7. An image forming apparatus comprising a sheet conveying device in which a plurality of rollers are arranged for feeding a sheet to an image forming position in order to execute an image forming operation, wherein the sheet conveying devices are arranged adjacent to each other. An image forming apparatus, wherein a cleaning unit is rotatably provided so as to come into contact with each of a plurality of rollers. 8. A release means for releasing the contact state of the cleaning means to a plurality of rollers,
8. The image forming apparatus according to claim 7, further comprising control means for controlling the cleaning means so that the cleaning means can be moved toward and away from the plurality of rollers via the releasing means as needed. 9. The control means controls the releasing means to press the cleaning means against the plurality of rollers during image formation, and controls the releasing means to separate the cleaning means from the plurality of rollers during non-image formation. The sheet conveying device according to claim 8. 10. The control means, when the number of times of image forming operation reaches a predetermined number, the cleaning means is brought into pressure contact with a plurality of rollers and separated after a predetermined time. Sheet conveying device. 11. The image forming apparatus according to claim 8, wherein the control unit contacts the cleaning unit with a plurality of rollers for a certain period of time in response to power-on of the image forming apparatus and then separates them from each other. apparatus.