JP4591382B2 - Paper feed roller cover and image forming apparatus having the same - Google Patents

Description

  The present invention relates to a paper feed roller cover capable of maintaining paper feed performance even with a paper feed roller to which dust such as paper dust or dust easily adheres, and an image forming apparatus including the same.

  2. Description of the Related Art Conventionally, in image forming apparatuses such as laser printers, facsimile machines, and copiers, a blade or brush is brought into contact with a developing roller or a fixing roller to scrape off dust adhering to the roller such as a lump of toner. (For example, refer to Patent Document 1).

Similarly, in the paper feed roller that transports the paper placed on the paper tray to the inside of the image forming apparatus, dust such as paper dust or external dust adheres to the paper feed roller. Some of them are provided with a cleaning device. In particular, image formation with a paper tray that does not have a dust cover on the front side of the paper, for example, a paper tray in which the lower part is formed in a box shape and the upper part is formed only of a metal or resin stand. In the apparatus, since external dust easily enters the image forming apparatus from the paper tray, dust such as paper dust and dust tends to adhere to the paper feed roller.
Japanese Patent Application Laid-Open No. 11-202581

  As described above, if dust such as paper dust or dust remains on the paper feed roller, the coefficient of friction between the paper feed roller and the paper becomes small and the paper feed performance of the paper feed roller deteriorates. Therefore, it is important to provide a cleaning device such as a blade or a brush on the paper feed roller. However, since such a cleaning device requires parts and the like for pressing the blade and the brush against the paper feed roller, it is necessary to secure a space around the paper feed roller in order to provide the cleaning device. With the recent miniaturization of image forming apparatuses, there is almost no space for installing a cleaning device having blades and brushes inside the image forming apparatus.

  Therefore, in view of the above problems, the present invention provides a paper feed roller cover that can remove dust such as paper dust and dust attached to the paper feed roller with a simple configuration without using a large cleaning device, and the same. An object of the present invention is to provide an image forming apparatus including the above.

The paper feed roller cover of the present invention is a paper feed roller cover that is attached to a paper feed roller that transports the paper placed on the paper tray to the inside of the image forming apparatus, and is substantially the same length as the axial length of the paper feed roller. A cover portion having a long side and covering a part of the outer peripheral surface of the paper feed roller; and a substantially semicircular cutout that is provided at a substantially right angle from the long side of the cover portion to support the cover portion. By attaching the notch to the shaft of the paper feed roller, the cover portion is rotatably supported so as to cover a part of the outer peripheral surface of the paper feed roller without synchronizing with the rotation of the paper feed roller. A plurality of projecting portions arranged in a row with a space between surfaces of the cover portion covering the paper feed roller and the paper feed roller side of the cover portion, the paper feed of the cover portion The long side of the length approximately the same as the roller shaft length With both ends of the protruding portion arranged on the central portion as vertices and a plurality of protrusions arranged in a substantially V-shape in the rotational direction tip side of the paper feed roller, the said cover portion by the supporting portion When attached to and supported by the shaft of the paper feed roller, the cover portion is rotated by its own weight so as to be close to the outer peripheral surface of the paper feed roller, and the protruding portion contacts the outer peripheral surface of the paper feed roller. Features.

  According to the present invention, since the attachment portion of the support portion of the paper feed roller cover is rotatably attached to the shaft of the paper feed roller, when the support portion is attached to the shaft of the paper feed roller, the paper feed roller Since the protruding part of the cover part supported by the support part by the weight of the cover comes into contact with the outer peripheral surface of the paper feed roller, the paper feed roller can be configured with a simple configuration without using a large cleaning device equipped with a blade or a brush. Dust such as adhering paper dust and dust can be removed, and the paper feed performance of the paper feed roller can be maintained.

The invention according to claim 1 of the present invention is a paper feed roller cover attached to a paper feed roller for transporting paper placed on a paper tray into the image forming apparatus, and is substantially the same as the axial length of the paper feed roller. A cover portion having a long side and covering a part of the outer peripheral surface of the paper feed roller; and a substantially semicircular cut provided to support the cover portion by being connected substantially at right angles from the long side of the cover portion. By attaching the notch to the shaft of the paper feed roller with a notch, the cover can be rotated so as to cover a part of the outer peripheral surface of the paper feed roller without synchronizing with the rotation of the paper feed roller. A plurality of projecting portions arranged in a row with a space between surfaces of the cover portion covering the paper feed roller and the paper feed roller side of the cover portion. Inside the long side of approximately the same length as the paper roller axis With both ends of the projecting portion disposed on part as vertices and a plurality of protrusions arranged in a substantially V-shape in the rotational direction tip side of the paper feed roller, the paper said cover portion by the supporting portion When attached to and supported by the shaft of the paper roller, the cover portion is rotated by its own weight so as to be close to the outer peripheral surface of the paper feed roller, and the protruding portion contacts the outer peripheral surface of the paper feed roller. And

  The paper feed roller cover is attached to the shaft of the paper feed roller by the attachment part of the support part of the paper feed roller cover, and the cover part supported by the support part covers a part of the outer peripheral surface of the paper feed roller. . Therefore, even if a part of the outer peripheral surface of the paper feed roller is visible from the outside of the image forming apparatus, the exposed portion is covered with the cover portion, so the user inserts the paper into the paper tray. In this case, it is possible to prevent the fingertip from being accidentally inserted and caught in the paper feed roller. Since such a paper feed roller cover is rotatably attached to the shaft of the paper feed roller by the attachment portion of the support portion, the cover portion comes close to the outer peripheral surface of the paper feed roller by its own weight. The protrusion provided on the side of the cover that faces the paper feed roller of the paper feed roller cover, that is, the back side of the paper feed roller cover, contacts the outer peripheral surface of the paper feed roller. To do. When the paper feed roller rotates in this state, the protruding portion scrapes off dust such as paper dust and dust attached to the paper feed roller. Thereby, dust adhering to the paper feed roller is removed, and the paper feed roller can maintain paper feed performance. As described above, according to the present invention, the paper feed roller cover for preventing the user's finger from being caught is brought into contact with the paper feed roller by its own weight without using a pressing member or the like, so that the protruding portion becomes the paper feed roller. It is also possible to scrape dust such as paper dust and dust attached to the paper, so that it is possible to maintain the paper feed performance of the paper feed roller with a simple configuration without using a large cleaning device equipped with blades and brushes. it can.

  When the paper feed roller rotates, the protrusion that is in contact with the outer peripheral surface of the paper feed roller scrapes off dust adhering to the surface of the paper feed roller. At this time, the protrusion is continuously formed. In some cases, the resistance force increases with the paper feed roller, and the paper feed roller cannot rotate smoothly. However, according to the paper feed roller cover of the present invention, since the plurality of protrusions are arranged with a space therebetween, the resistance force due to friction is reduced compared to the continuously formed protrusion, and the protrusion It is possible to smoothly rotate the paper feed roller while scraping off dust adhering to the paper feed roller.

  Since the protrusion is formed in a substantially V shape, the dust adhering to the paper feed roller is scraped off along with the rotation of the paper feed roller, and is gradually scraped from the center of the protrusion toward the end. Go. Accordingly, it is possible to prevent the scraped dust from collecting on the protruding portion, and it is possible to maintain the dust scraping performance of the paper feed roller cover.

According to a second aspect of the present invention, there is provided an image forming apparatus provided with a paper feed roller cover according to the first aspect of the present invention.

  With this configuration, the sheet feeding performance of the sheet feeding roller can be maintained with a simple configuration, and the image forming apparatus can be downsized. Even when external dust easily enters the inside of the image forming apparatus from the paper tray, dust attached to the paper feed roller can be removed with high precision. Since there is no need to use a large paper tray with a cover, the manufacturing cost of the paper tray can be reduced.

(Embodiment)
Hereinafter, an image forming apparatus including a paper feed roller cover according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 is a perspective view schematically showing a facsimile apparatus equipped with the image forming apparatus of the present invention. The facsimile apparatus shown in FIG. 1 will be described as an example. FIG. 2 is a cross-sectional view of the facsimile apparatus shown in FIG. FIG. 3 is a perspective view of a paper feed roller and a paper feed roller cover of the facsimile apparatus. FIG. 4 is an exploded view of the paper feed roller cover and the paper feed roller in the present embodiment. FIG. 5 is a detailed cross-sectional view showing a paper feed roller and a paper feed roller cover of the facsimile apparatus shown in FIG.

  As shown in FIGS. 1 and 2, the facsimile apparatus 1 according to the present embodiment includes an apparatus main body 10, a front unit 23 that can be opened and closed in front of the upper part of the apparatus main body 10, and an upper rear of the apparatus main body 10. The rear unit 24 provided so that opening and closing is possible is provided. A paper tray 20 is detachably attached to the apparatus main body 10.

  Although the front unit 23 mainly includes operation keys and a display device, they are not directly related to the gist of the present invention, and thus detailed description thereof is omitted in the drawings and the specification. The rear unit 24 includes a paper feeding unit that takes in the paper placed on the paper tray 20 inside the housing. The apparatus main body 10 includes an image forming unit that performs printing on a sheet conveyed by the paper feeding unit inside the housing.

  The paper tray 20 includes a holding unit 22 that holds the lower part of the paper and a stand 21 that supports the upper side of the paper inserted into the holding unit 22 from the back side. The holding part 22 is formed in a box shape whose upper side is open, and the stand 21 is formed in an inverted U shape made of metal or resin and is locked to the holding part 22.

  As shown in FIGS. 2 and 3, a paper passing portion 11 is formed at the position on the rear side of the upper surface of the rear unit 24 at the top of the apparatus body 10 and where the paper tray 20 is mounted. The sheet passing section 11 serves as a port for taking in the sheet placed on the sheet tray 20 into the apparatus main body 10. Further, a paper feed roller 12 and a separation pad 14 constituting a paper feed unit are provided inside the rear unit 24 and downstream of the paper passing unit 11.

  The outer peripheral surface 122 of the paper feed roller 12 is made of a material having a high friction coefficient such as rubber, and a plurality of grooves 123 (so-called knurling) are formed on the surface along the axial direction of the paper feed roller 12. Yes. When the paper placed on the paper tray 20 is conveyed by the groove 123, the outer peripheral surface 122 of the paper feed roller 12 can easily bite the paper placed on the uppermost surface of the paper tray 20 and separate them one by one. It has become.

  As shown in FIGS. 3, 4, and 5, a paper feed roller cover 13 is attached to the paper feed roller 12. This is because a hole is opened at a position near the paper feed roller 12 due to the structure of the mold when manufacturing the housing of the rear unit 24, and the paper feed roller 12 can be seen from the outside as it is. When a user inserts a sheet into the sheet tray 20, for example, the user's fingertip is mistakenly inserted to be caught in the sheet feeding roller 12, and outside dust or the like falls into the hole to feed the sheet. It is mounted to prevent the roller 12 from adhering. A paper feed roller cover 13 is disposed on the back side of the housing of the rear unit 24 so as to close the hole.

  The paper feed roller cover 13 has a cover 131 formed in a substantially rectangular shape with a long side substantially the same as the axial length of the paper feed roller 12, and a substantially right angle from the long side of the cover 131. It is provided with a support part 133 that supports the cover part 131 and has an attachment part 134 for attaching the paper feed roller cover 13 to the shaft 121 of the paper feed roller 12.

  When the cover 131 is attached to the back surface, that is, when the paper feed roller cover 13 is attached to the shaft 121 of the paper feed roller 12, a plurality of protrusions are spaced from the surface of the cover 131 on the paper feed roller 12 side. A substantially V-shaped protrusion 132 is formed in such a manner that both ends thereof are arranged in a row and both ends of the central portion expand toward the front side in the rotation direction of the paper feed roller 12.

  The attachment part 134 is formed at both ends of the support part 133. The attachment portion 134 is formed with a notch 135 having a substantially semicircular shape opened downward so as to be fitted from above the shaft 121 and having a slightly larger diameter than the shaft 121. Thus, when the paper feed roller cover 13 is attached to the shaft 121 of the paper feed roller 12, the paper feed roller cover 13 can be individually rotated without rotating in synchronization with the shaft 121 of the paper feed roller 12. .

  When the notch 135 formed in the attachment portion 134 of the paper feed roller cover 13 is fitted into the shaft 121 of the paper feed roller 12 from above, as shown in FIGS. 2 and 3, the whole paper feed roller cover 13 has its own weight. , The cover 131 covers the upper part of the outer peripheral surface 122 of the paper feed roller 12 and the protrusion 132 contacts the outer peripheral surface 122 of the paper feed roller 12. It will be in the state.

  Next, how the plurality of sheets placed on the sheet tray 20 are conveyed into the apparatus main body 10 by rotating the sheet feeding roller 12 will be described.

  The paper placed on the paper tray 20 is inserted toward the paper feed roller 12 as indicated by an arrow A in FIG. When the paper feed roller 12 rotates in the direction indicated by the arrow B in FIG. 5, the outer peripheral surface 122 of the paper feed roller 12 bites into the uppermost sheet among the sheets placed on the sheet tray 20. Then, friction is generated between the paper feed roller 12, the paper, and the separation pad 14, and only the uppermost paper is separated and conveyed by this friction. When printing is completed and the next sheet becomes necessary, the sheet feeding roller 12 rotates again to separate and transport the uppermost sheet.

  As described above, as the paper is repeatedly transported, the paper dust of the paper or external dust that has entered from the holding portion 22 of the paper tray 20 adheres to the outer peripheral surface 122 of the paper feed roller 12. . For example, an arrow B in FIG. 5 indicates dust attached to the paper feed roller 12.

  The dust adhering to the outer peripheral surface 122 of the paper feed roller 12 moves to the cover 131 side of the paper feed roller cover 13 as the paper feed roller 12 rotates in the direction of arrow B. At this time, since the protruding portion 132 formed on the back surface side of the cover portion 131 is in contact with the outer peripheral surface 122, the attached dust hits the protruding portion 132 of the cover portion 131, and further, the paper feed roller It is scraped off from the outer peripheral surface 122 by the rotation of 12. Then, the scraped scraped outer peripheral surface is along the protruding portion 132 formed in a substantially V shape so as to spread toward the front side in the rotation direction of the paper feed roller 12 as the paper feed roller 12 rotates. The sheet 122 is scraped to the end of the sheet feeding roller 12 while sliding on the surface of 122.

  As described above, the paper feed roller cover 13 can remove dust adhering to the outer peripheral surface 122 of the paper feed roller 12. Thereby, the friction coefficient of the paper feed roller 12 can be kept high, and the paper feed performance of the paper feed roller 12 can be maintained even if the paper feed unit repeatedly feeds paper.

  As described above, according to the present embodiment, the paper feed roller cover 13 that is mounted to prevent the user's finger from being caught or to prevent dust or the like from adhering to the outside is used as the pressing member. A blade for removing dust adhering to the paper feed roller 12 because it can contact the outer peripheral surface 122 of the paper feed roller 12 by its own weight without using it, and scrape off and remove the dust by the protrusion 132. In addition, the paper feed performance of the paper feed roller 12 can be maintained with a simple configuration without using a large cleaning device provided with a brush, and the apparatus main body 10 of the image forming apparatus can be downsized.

  In the present embodiment, the protrusion 132 of the paper feed roller cover 13 has a plurality of protrusions arranged in a row with a gap therebetween. As long as dust adhering to the surface 122 in contact with the surface 122 can be scraped off, the protrusions may be formed continuously in a straight line. However, since the protrusion 132 of the paper feed roller cover 13 is always in contact with the outer peripheral surface 122 of the paper supply roller 12, the outer peripheral surface 122 and the protrusion 132 of the cover 131 are There is a possibility that a resistance force due to friction is generated between the two and the rotation of the sheet feeding roller 12 is hindered. Therefore, in order to relieve the resistance force caused by such friction, it is desirable that a plurality of protrusions be arranged with a gap therebetween as in the protruding portion 132 of the present embodiment.

  Further, in the present embodiment, the protruding portion 132 is formed in a substantially V shape so as to expand toward the front side in the rotation direction of the paper feed roller 12, but is not limited thereto, and is attached to the paper feed roller 12. As long as dust that has been removed can be removed, it may be formed in a straight line so as to be parallel to the axial direction of the paper feed roller 12. However, in order to scrape off the paper scraped from the paper feed roller 12 from the center of the protruding portion 132 toward both ends without staying at the protruding portion 132, the protruding portion is protruded as in the present embodiment. It is desirable that the both ends are in the shape of a V shape or a U shape arranged at the front side of the rotation direction rather than the center of the portion 132. Accordingly, it is possible to prevent the scraped dust from staying as it is, and entering the gap between the protruding portion 132 and the outer peripheral surface 122 of the paper feed roller 12, and scraping performance of the paper feed roller cover 13. Can be maintained.

  As described above, according to the present embodiment, dust attached to the outer peripheral surface 122 of the paper feed roller 12 can be accurately removed by the paper feed roller cover 13. Therefore, in the paper tray 20, there is no dust cover that covers the entire front surface of the paper placed on the paper tray 20, and external dust easily enters the inside of the apparatus main body 10 from the paper tray. Even so, the sheet feeding performance of the image forming apparatus can be maintained. Therefore, the paper tray 20 can be configured simply by the holding portion 22 that holds the lower side of the paper and the stand 21 that supports the upper side of the paper as in the present embodiment, and the manufacturing cost of the paper tray can be reduced. You can also.

  The present invention is useful as a paper feed roller cover capable of removing dust such as paper dust and dust attached to the paper feed roller. In particular, the present invention can remove dust adhering to the paper feed roller with a simple configuration and simple configuration without using a large cleaning device, so that the paper feed roller cover can be reduced in size. Can be suitably used.

Perspective view of an image forming apparatus according to the present embodiment AA line sectional view of FIG. The perspective view of the paper feed roller provided with the paper feed roller cover in this embodiment Exploded view of paper feed roller cover and paper feed roller in this embodiment FIG. 3 is a cross-sectional view of a main part showing a paper feed roller cover and a paper feed roller of the image forming apparatus according to the present embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Image forming apparatus 10 Main body 11 Paper passing part 12 Paper feed roller 13 Paper feed roller cover 14 Separation pad 20 Paper tray 21 Stand 22 Holding part 23 Front unit 24 Rear unit 121 Shaft 122 Outer surface 123 Groove 131 Cover part 132 Projection part 133 Supporting part 134 Mounting part 135 Notch

Claims (2)

A paper feed roller cover attached to a paper feed roller for transporting the paper placed on the paper tray into the image forming apparatus;
A cover portion having a long side substantially the same as the axial length of the paper feed roller and covering a part of the outer peripheral surface of the paper feed roller; and the cover portion provided continuously at a substantially right angle from the long side of the cover portion And a part of the outer peripheral surface of the paper feed roller is covered without synchronizing with the rotation of the paper feed roller by attaching the notch to the shaft of the paper feed roller. And a plurality of projecting portions arranged in a row with a space between the support portion that covers the paper feed roller and the surface of the cover portion that covers the paper feed roller. The both ends of the cover portion are substantially on the front side in the rotation direction of the paper feed roller, with the protruding portion arranged at the center of the long side of the cover portion having the same length as the axial length of the paper feed roller. and a plurality of protrusions arranged in a V-shape, the supporting part The protrusion is in contact with the cover portion on the outer peripheral surface of the rotation and the feed roller so that the cover part by its own weight and supports mounted on the shaft of the paper feed roller is close to the outer peripheral surface of the feed roller A paper feed roller cover. An image forming apparatus comprising the paper feed roller cover according to claim 1 .

Images