JP4762795B2 - Sheet material feeding device and image forming apparatus provided with the same - Google Patents

Description

  The present invention relates to a sheet material feeding apparatus that supplies a sheet material to image forming means for forming an image on the sheet material, and an image forming apparatus such as a printer, a copier, a facsimile machine, and a printing machine using the sheet material feeding apparatus.

  In an image forming apparatus such as a printer, it is necessary to feed a sheet material to the image forming unit. At that time, the sheet material fed from the sheet material stacking unit to the image forming unit has foreign matters such as paper dust. Is adhered to the sheet material while substantially adhering to the sheet material. As a result, defects such as defective image formation and image smearing occur.

  In addition, the sheet material conveying member, the image transfer member, the image fixing member and the like positioned along the sheet material conveying path are also contaminated by the foreign matter adhering to the sheet material, and as a result, the sheet material conveying defect, the image defect, and the like occur. Therefore, foreign matter such as paper dust adhering to the sheet (recording paper) fed and conveyed from the paper feeding unit is reduced, and the conveyance roller, transfer roller, photoconductor, and fixing unit are reduced. There has been proposed a technique for reducing dirt caused by paper dust such as a roller and improving image quality and sheet conveyance quality (for example, see Patent Document 1).

  Further, the image forming apparatus and the paper feeding device disclosed in Patent Document 2 are intended to solve the problem caused by foreign matters such as paper dust attached to the paper fed and conveyed from the paper feeding unit. Discloses a document conveying device, an image reading device, and an image forming apparatus that prevent foreign matter from being taken in along with a loaded sheet. By providing foreign material removal means on the upstream side of the material conveyance direction, the foreign material adhering to the sheet material fed from the sheet material stacking member can be removed. In some cases, magnetic foreign matter such as metal powder may adhere to the sheet material depending on the location of the image forming apparatus (for example, the line side of the factory, the vicinity of the dental clinic's examination table, etc.). ) Magnetism It becomes possible to cause problems such as defective image formation and image contamination by foreign matter.

  However, in addition to the above-mentioned patent documents, the present inventor and others are not aware of a technique that takes into account the function of removing these foreign substances (such as metal powder) from magnetic foreign substances. Therefore, there still exists a problem of causing a sheet material conveyance defect at the same time as a defect such as an image formation defect or an image stain.

  Further, since the foreign substance removing means described in the above-mentioned patent document is provided in a form in which a member is separately added on the sheet material conveyance path having a conventional configuration, it is difficult to reduce the size of the apparatus.

JP 2005-255317 A JP-A-11-208918 JP 2002-362754 A

  The present invention has been made in view of the above-described conventional problems, and at the same time, proposes an apparatus that realizes stable sheet material feeding performance without causing image defects and conveyance problems, and at the same time, uses the apparatus and the apparatus. It is an object of the present invention to propose a configuration that can realize downsizing of an image forming apparatus.

A sheet material feeding apparatus according to claim 1 of the present invention includes a sheet material feeding member that is rotatable and feeds one sheet material from a plurality of sheet materials stacked on a stacking member to a separation unit. in the feeding device, the sheet material feeding member for feeding the sheet material, the rubber roller is a member formed in contributing elastic body feeding of the sheet material, the metal powder or the like in line with the outer periphery of the rubber roller It consists of a magnet as a foreign matter removing member that removes magnetic foreign matter, and a groove in the thrust direction is provided in the outer circumferential portion of the rubber roller in a knurl shape, and the magnet has a roller shape as a whole. One end side that is the insertion side of the magnet is opened, and a plurality of magnet strips are formed in an interdigital shape, so that the interdigital magnet strips enter a groove in the outer peripheral portion of the rubber roller. The serial magnet characterized by comprising attached to said rubber roller.

According to the second aspect, in the sheet material feeding device according to the first aspect, the relationship between the outer diameter of the foreign material removing member and the outer diameter of the sheet material feeding member is
D1 ≦ D2
(However, D1: the outer diameter of the member having a foreign matter removing function, D2: the outer diameter of the sheet material feeding member)
And then, the outer periphery of the rubber roller is characterized Rukoto such so as to be positioned on the outer peripheral side of the magnet.

According to a third aspect of the present invention, there is provided an image forming apparatus comprising the sheet material feeding device according to the first or second aspect .

  In the sheet material feeding device of the present invention and the image forming apparatus using the same, the foreign material removing member having a function of removing magnetic foreign materials such as metal powder at the rotation center position of the feeding member for feeding the sheet material By providing this, it is possible to realize a stable sheet material feeding performance without causing an image defect or a conveyance defect, and at the same time, it is possible to realize downsizing of the apparatus.

  The best mode for carrying out the present invention will be described below with reference to the embodiments shown in the drawings.

  FIG. 1 shows an example of an image forming apparatus provided with a sheet material feeding device according to the present invention, and FIG. 2 shows a paper feeding device (A) and a feeding member (B). The image forming apparatus 1 includes a feeding device 2 that transports and feeds a sheet material in a sheet material discharging direction while forming an image on the sheet material inside the apparatus main body. Feeds the sheet material in the sheet material feeding direction A in contact with the sheet material stacking member 3 supporting the sheet surface of the sheet material to be fed, and the sheet material stacked on the sheet material stacking member 3 A feeding member 4 is provided.

  The feeding member 4 has a function of removing magnetic foreign matter such as metal powder along the outer periphery with respect to the rubber roller 4a which is a member formed of an elastic body contributing to feeding of the sheet material. A magnet 4b is provided as a member. The magnet 4b has a roller shape as a whole, but one end side (the insertion side to the rubber roller 4a indicated by an arrow in 2B in the figure) is opened, and a plurality of magnet strips are formed in a so-called interdigital shape. Each of these can be attached so as to enter a later-described groove of the rubber roller 4a. In the figure, 4c is a core material. With this configuration, when feeding the sheet material, it is possible to remove the magnetic foreign matter adhering to the sheet material, and as a result, a stable sheet that does not cause image defects or conveyance problems The material feeding performance can be realized, and at the same time, it is not necessary to provide a separate foreign matter removing function. Therefore, the apparatus can be downsized at least by that amount.

  FIG. 3 shows a cross section of the feeding member 4 shown in FIG. A groove 4d in the thrust direction is provided in the outer circumferential portion of the rubber roller 4a of the feeding member 4 in a knurl shape, and a magnet having a function of removing magnetic foreign substances such as metal powder in a recess formed by the groove 4d. By positioning 4b, the collected foreign matter is accumulated in the recess, and as a result, a stable foreign matter removing function is realized in which the collected foreign matter is not likely to flow out.

  FIG. 4 shows another embodiment of the sheet material feeding apparatus according to the present invention. FIG. 5 shows a sectional view thereof. In this embodiment, a pair of magnets 5 and 5 are provided as members having a foreign matter removing function at positions symmetrical with respect to the center of the sheet material in the direction orthogonal to the feeding direction A, and a scraping member 6 is provided on the apparatus main body side. Thus, it is possible to realize a more reliable foreign matter removal function and at the same time, by providing the magnet 5 having the foreign matter removal function with a function of suppressing the end curl of the sheet material stacked on the sheet material stacking member 3. Stable conveyance quality is realized without causing any troubles in sheet material conveyance (non-feed, jam, etc.).

  FIG. 6 shows another embodiment of the sheet material feeding apparatus according to the present invention. FIG. 7 shows a cross-sectional view thereof. In this embodiment, a scraping member 8 for scraping off the foreign matter adhering to the outer peripheral surface of the magnet 5 which is a member having a foreign matter removing function is provided so as to contact the outer peripheral portion of the magnet 5 having the foreign matter removing function. Thus, a stable foreign substance removal function can be realized over time.

  In particular, the scraping member 8 has a substantially U-shaped cross section so that the scraped foreign matter can be collected and accumulated in the scraping member 8, and the scraping member 8 is further configured as an apparatus main body of the image forming apparatus 1. By providing it detachably, it is possible to realize a foreign substance removal function that is more stable over time.

  In the present invention, only the magnet that uses the magnetism to remove the magnetic foreign material is shown. However, the present invention is not limited to this, and various means can be adopted. For example, it may be possible to simply scrape and collect and store the scraped foreign matter in a remote place.

In any of the above embodiments, for example, as shown in FIG. 3, the relationship between the outer diameter of the foreign matter removing member (magnet 4b in this example) and the outer diameter of the sheet material feeding member (rubber roller 4a in this example). The
D1 ≦ D2
(However, D1: an outer diameter of a member having a foreign matter removing function, for example, the outer diameter of a magnet 4b or 5; D2: an outer diameter of a sheet material feeding member, for example, a rubber roller 4a); If the relationship with the outer diameter of the material feeding member is clarified, it is possible to eliminate general sheet material conveyance problems (non-feed, jam, etc.).

  In the above-described embodiment, only the example in which the grooves are provided in a knurled shape is shown, but the present invention is not limited to this example. Of course, it may be made in a form other than the knurled shape.

1 is a perspective view illustrating an example of an image forming apparatus including a sheet material feeding device according to the present invention. FIG. 2 is a perspective view (A) illustrating a sheet feeding device provided in the image forming apparatus of FIG. 1 and an exploded perspective view (B) illustrating a feeding member in detail. FIG. 3 is a cross-sectional view of the feeding member shown in FIG. 2. It is a perspective view which shows 2nd Example of the sheet material feeding apparatus which concerns on this invention. It is sectional drawing of the Example shown in FIG. It is a perspective view which shows 3rd Example of the sheet material feeding apparatus which concerns on this invention. It is sectional drawing of the Example shown in FIG.

Explanation of symbols

1: image forming apparatus 2: feeding apparatus 3: sheet material stacking member A: sheet material feeding direction 4: feeding member 4a: rubber roller 4b, 5: magnet 4c: core material 4d: groove 6, 7: scraping member

Claims (3)

In a sheet material feeding apparatus having a rotatable sheet material feeding member that feeds one sheet material from a plurality of sheet materials stacked on a stacking member to a separation unit,
The sheet material feeding member that feeds the sheet material is a rubber roller that is a member formed of an elastic body that contributes to the feeding of the sheet material, and removes magnetic foreign substances such as metal powder along the outer periphery of the rubber roller. Consisting of a magnet as a foreign material removal member
A groove is provided in a knurled shape in the thrust direction on the outer peripheral portion of the rubber roller,
The magnet as a whole has a roller shape, the one end side which becomes the insertion side to the rubber roller is opened, and a plurality of magnet strips are formed in a comb shape,
The sheet material feeding device, wherein the magnet is attached to the rubber roller so that the thin piece of the interdigital magnet enters the groove in the outer peripheral portion of the rubber roller. In the sheet material feeding device according to claim 1 , the relationship between the outer diameter of the foreign matter removing member and the outer diameter of the sheet material feeding member,
D1 ≦ D2
(However, D1: the outer diameter of the member having a foreign matter removing function, D2: the outer diameter of the sheet material feeding member)
And then, the sheet feeding apparatus according to claim Rukoto such as the outer periphery of the rubber roller is positioned on the outer peripheral side of the magnet. An image forming apparatus comprising the sheet material feeding device according to claim 1.