JP2014055057A - Paper feed roller - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a paper feed roller having a relief way for paper dust falling in an axial groove and capable of stably transporting paper even in a long-term use.SOLUTION: A cylindrical part (30) is divided into a first area (30a) a second area (30b) and a third area (30c) by two circumferential grooves (33). A plurality of axial grooves (32) extending along the axial direction are formed over the total length of each area. That is, the plurality of axial groove (32) and the two circumferential grooves (33) are formed in a continuous mode. Thus, the circumferential grooves (33) serve as a relief way for paper dust captured in the axial grooves (32), so that there is no risk that paper dust stays in the axial grooves (32) excessively to leak out.

Description

  The present invention relates to a paper feed roller suitable for a paper feed roller (pickup roller, feed roller, retard roller) used in a paper feed device of a device such as a copying machine, a printer, and a facsimile, and a transport roller. More specifically, the present invention relates to a paper feed roller having a plurality of grooves on a cylindrical surface, and is particularly suitable for a paper feed roller.

  Some paper feed units of copiers, printers, facsimiles, and the like include a pickup roller, a feed roller, and a retard roller to feed paper one by one.

  For example, in the FRR type paper feeder as shown in FIG. 1, the pickup roller 1 feeds the paper 5 from the paper tray 6 to the separation unit, and the separation unit includes a torque limiter 4 provided in pressure contact with the feed roller 2. A double feed of the paper 5 is prevented by the provided retard roller 3.

  That is, when a paper feed command is issued, the pickup roller 1 and the feed roller 2 start to rotate. At that time, the retard roller 3 pressed against the feed roller 2 is also rotated together with the feed roller 2. The sheet 5 called from the tray 6 by the pickup roller 1 enters between the feed roller 2 and the retard roller 3, and is pressed and advanced by the feed roller 2 and the retard roller 3. At this time, the retard roller 3 is given a rotational force in the direction of returning the paper 5, but the paper is sandwiched between the feed roller 2 and rotated.

  When two sheets of paper are called by the pickup roller 1 and enter between the feed roller 2 and the retard roller 3, the retard roller 3 is given a predetermined torque in the direction of returning the paper 5, so that the paper 2 When the sheets enter between the feed roller 2 and the retard roller 3 together, the retard roller 3 rotates in the returning direction to return the paper 5 in contact with the retard roller 3, and only the uppermost paper in contact with the feed roller 2 advances. To do.

  In such a paper feed roller, when paper dust or its own wear debris remains on the surface, the coefficient of friction decreases, and the paper cannot be stably conveyed. Therefore, a paper feed roller is known in which a groove for allowing paper dust or the like to fall on the cylindrical surface is known. Such a paper feed roller is described in, for example, Japanese Patent Laid-Open No. 2000-159375 (Patent Document 1).

  As shown in FIG. 2, the paper feed roller 100 described in Patent Document 1 includes a shaft 120 and three cylindrical portions 110a, 110b, and 110c in which a plurality of axial grooves 112 extending along the axial direction are formed. Prepare. The three cylindrical portions 110a, 110b, and 110c are arranged side by side in the axial direction by shifting the position of the axial groove 112 from each other. By carrying out like this, it is supposed that the paper feed roller which can reduce abnormal noise, and its manufacturing method can be provided. The cylindrical portion of the paper feed roller as described above is generally made of synthetic rubber such as EPDM or polyurethane, and a method of molding using a split mold is known.

JP 2000-159375 A

  The paper feed roller described in Patent Document 1 is configured as described above. However, there is no escape route for the captured paper dust that falls into the axial groove 112 extending along the axial direction, and the captured paper dust or the like may accumulate and leak out.

  The present invention has been made to solve the above-described problems, and has an escape path such as paper dust that has fallen into an axial groove and captured, and can stably transport paper even in long-term use. An object of the present invention is to provide a paper feed roller capable of performing the above.

  The paper feed roller according to the present invention has a large number of grooves on the cylindrical surface. The cylindrical surface is divided into first, second and third regions in order along the axial direction of the paper feed roller by a boundary line extending in the circumferential direction of the paper feed roller, and each region has an axial direction. A plurality of axial grooves extending along the entire length of each region are formed along the second region, and the axial grooves in the second region are shifted in the circumferential direction with respect to the axial grooves in the first region and the third region. And circumferential grooves extending in the circumferential direction are formed at the boundary portions of the respective regions.

  Preferably, the axial groove in the first region and the axial groove in the third region are provided so as to be positioned on the same axis.

  Preferably, the axial groove and circumferential groove patterns of the first, second and third regions are symmetrical with respect to a line passing through the center of the second region.

  Preferably, the circumferential groove depth is greater than the axial groove depth.

  Preferably, the cylindrical surface has fourth and fifth regions so as to sandwich the first, second, and third regions, and the fourth region and the fifth region have a plurality of axial directions that extend the entire length of each region. Grooves are formed, and circumferential grooves extending in the circumferential direction are formed at the boundary between the first region and the fourth region and at the boundary between the third region and the fifth region, respectively. .

  Preferably, the axial groove in the fourth region and the axial groove in the fifth region are located on the same axis as the axial groove in the second region.

  In the present invention, the cylindrical surface is divided into first, second and third regions in order along the axial direction of the paper feed roller by a boundary line extending in the circumferential direction of the paper feed roller. A circumferential groove extending in the circumferential direction is formed in the boundary portion of.

  As a result, it is possible to provide a paper feed roller that has an escape path such as paper dust that has fallen into the axial groove and that can stably transport paper even in long-term use.

It is the schematic which shows the side surface of a paper feeder. 6 is a perspective view showing a paper feed roller 100 described in Patent Document 1. FIG. 1 is a perspective view showing a paper feed roller 10 according to a first embodiment of the present invention. FIG. 4 is a cross-sectional view of the cylindrical portion 30 shown in FIG. 3 cut along a plane along the circumferential direction that does not include the circumferential groove 33 and viewed from the outside in the axial direction. 4 is a cross-sectional view of the cylindrical portion 30 shown in FIG. 3 cut along a plane along the circumferential direction including a circumferential groove 33 and viewed from the outside in the axial direction. FIG. It is the schematic which looked at the cylindrical part 30 of the paper feed roller divided into five area | regions from the radial direction outer side.

(1) First Embodiment Hereinafter, an embodiment of the present invention will be described with reference to the drawings. FIG. 3 is a perspective view showing the paper feed roller 10 according to the first embodiment of the present invention.

  Referring to FIG. 3, the paper feed roller 10 includes a shaft 20 and a cylindrical portion 30 made of polyurethane and formed by a known method using a split mold, and the shaft 20 passes through the center in the axial direction. The cylindrical portion 30 includes a cylindrical surface 31 that is in contact with the paper to be conveyed, a plurality of axial grooves 32 that are recessed inward in the radial direction with respect to the cylindrical surface 31, and extend in the axial direction. It includes two circumferential grooves 33 extending along the direction indicated by the white arrow in the drawing in which the feed roller 10 rotates.

  The cylindrical portion 30 is divided into a first region 30a, a second region 30b, and a third region 30c by two circumferential grooves 33. A plurality of axial grooves 32 extending along the axial direction are formed over the entire length of each region. That is, it is formed in a form in which a plurality of axial grooves 32 and two circumferential grooves 33 are connected.

  As described above, the circumferential groove 33 extends along the circumferential direction, that is, the direction in which the paper feed roller 10 rotates, so that paper dust or the like that has fallen into the axial groove 32 and trapped therein is air. Also flows into the circumferential groove 33 easily. That is, since the circumferential groove 33 serves as an escape route for paper dust or the like trapped in the axial groove 32, there is no possibility that paper powder or the like accumulates in the axial groove 32 and leaks out.

  The axial grooves 32 of the first region 30a and the third region 30c are located on the same axis. By doing so, a frictional force for conveying the paper 90 is locally generated under the same conditions in the rotation direction of the paper feed roller 10. As a result, the paper 90 can be conveyed more straightly, and the occurrence of skew can be further prevented.

  Further, the groove patterns of the axial grooves 32 of the first to third regions 30a to 30c and the groove of the circumferential groove 33 are symmetrical with respect to a line passing through the center of the second region 30b. By doing so, the frictional force for transporting the paper 90 is more locally generated in the same condition in the rotational direction of the paper feed roller 10. As a result, the paper 90 can be conveyed more straightly, and the occurrence of skew can be further prevented.

  Note that the axial groove 32 of the second region 30b is positioned so as to be shifted in the circumferential direction with respect to the axial groove 32 of the first region 30a and the third region 30c. By doing so, it is possible to prevent the end portion of the conveyed paper from entering the axial groove 32, so that the occurrence of paper jam can be reduced.

  FIG. 4 is a cross-sectional view of the cylindrical portion 30 shown in FIG. 3 cut from a plane along the circumferential direction that does not include the circumferential groove 33 and viewed from the outside in the axial direction. FIG. 5 is a cross-sectional view of the cylindrical portion 30 shown in FIG. 3 cut along a plane along the circumferential direction including the circumferential groove 33 and viewed from the outside in the axial direction. 4 and 5, the cylindrical portion 30 is formed with a plurality of axial grooves 32 extending along the axial direction as described above. Referring to FIG. 5, the cylindrical portion 30 is further formed with a circumferential groove 33 extending along the circumferential direction as described above.

  The depth of the circumferential groove 33 is formed deeper than the depth of the axial groove 32 as shown in FIG. By doing so, the paper dust that has fallen into the axial groove 32 and captured is more likely to flow into the circumferential groove 33, so that the paper dust or the like may accumulate in the axial groove 32 and leak out. Can be further reduced.

  As described above, the cylindrical portion 30 is formed by a known method using a split mold. Here, when the three cylindrical portions 110a, 110b, and 110c described in Patent Document 1 are molded with a split mold and arranged side by side continuously, burrs appear at the boundary portion between the adjacent cylindrical portions 110. On the other hand, in the cylindrical portion 30 of this embodiment, the circumferential groove 33 is formed at the boundary portion between the adjacent regions of the cylindrical portion 30, so that no burrs are generated.

  In this embodiment, the case where the axial grooves 32 of the first region 30a and the third region 30c are located on the same axis has been described. .

  In this embodiment, the patterns of the axial grooves 32 of the first to third regions 30a to 30c and the groove pattern of the circumferential groove 33 are symmetrical with respect to a line passing through the center of the second region 30b. Although a certain case has been described, the present invention is not limited to this, and the shape passing through the center of the second region 30b may be different.

(2) Second Embodiment Next, a paper feed roller 10 according to a second embodiment of the present invention will be described. FIG. 6 is a schematic view of the cylindrical portion 30 of the paper feed roller according to this embodiment viewed from the outside in the radial direction. In this embodiment, the cylindrical portion of the paper feed roller 10 according to the first embodiment is provided except that the cylindrical portion 30 is divided into five regions by four circumferential grooves 33. It is the same shape as 30. Therefore, the same parts are denoted by the same reference numerals, and the same description is omitted.

  Referring to FIG. 6, the cylindrical portion 30 includes a first region 30a, a second region 30b, a third region 30c, a fourth region 30d, and a fifth region 30e by four circumferential grooves 33. It is divided into. A plurality of axial grooves 32 extending along the axial direction are formed over the entire length of each region. Similar to the cylindrical portion 30 of the paper feed roller 10 according to the first embodiment shown in FIG. 3, the axial grooves 32 of the first region 30a and the third region 30c are located on the same axis.

  Furthermore, the axial grooves 32 of the second region 30b, the fourth region 30d, and the fifth region 30e are located on the same axis. Furthermore, the groove patterns of the axial grooves 32 and the circumferential grooves 33 of the first to fifth regions 30a to 30e are symmetrical with respect to a line passing through the center of the second region.

  Since the cylindrical portion 30 is divided into five regions, the frictional force for conveying the paper 90 is compared with the rotation direction of the paper feed roller 10 as compared with the first embodiment divided into three regions. And more locally under the same conditions. As a result, the paper 90 can be conveyed more straightly, and the occurrence of skew can be further prevented.

  In this embodiment, the case where the cylindrical portion 30 is divided into five regions has been described. However, the present invention is not limited to this, and the cylindrical portion 30 may be divided into seven or more odd regions, or may be divided into even regions. May be.

  In addition, in this embodiment, although the axial direction groove | channel 32 of the 2nd area | region 30b, the 4th area | region 30d, and the 5th area | region 30e demonstrated on the same axis line, it is not restricted to this, It may be displaced.

  The paper feed roller 10 according to the first and second embodiments described above is a paper feed roller (pickup roller, feed roller, retard roller) used in a paper feed device of a device such as a copying machine, a printer, or a facsimile machine. Also, it is suitable as a conveyance roller, and particularly suitable for a paper feed roller.

  In the first and second embodiments described above, the case where the cylindrical portion 30 is formed from polyurethane, which is a kind of synthetic rubber, is described. However, the present invention is not limited to this, and the cylindrical portion 30 is formed from EPDM or other synthetic rubber. It may be made of a material other than synthetic rubber.

  In the first and second embodiments described above, the case where the depth of the circumferential groove 33 is formed deeper than the depth of the axial groove 32 has been described. Not limited to this, it may be formed shallower than the groove depth of the axial groove 32 or may be the same depth.

  As mentioned above, although embodiment of this invention was described with reference to drawings, this invention is not limited to the thing of embodiment shown in figure. Various modifications and variations can be made to the illustrated embodiment within the same range or equivalent range as the present invention.

  According to the present invention, the paper feed roller has an escape path such as paper dust that has fallen into the axial groove, and can stably transport the paper even in long-term use. Therefore, the paper feed roller is advantageous as a paper feed roller. Used for.

  DESCRIPTION OF SYMBOLS 1 Pickup roller, 2 Feed roller, 3 Retard roller, 4 Torque limiter, 5 Paper, 6 Paper tray, 10 Paper feed roller, 20 Shaft, 30 Cylindrical part, 30a 1st area | region, 30b 2nd area | region, 30c 3rd Area, 30d 4th area, 30e 5th area, 31 cylindrical surface, 32 axial groove, 33 circumferential groove, 100 paper feed roller described in Patent Document 1, 110a to 110c described in Patent Document 1 Cylindrical part, 111 Cylindrical surface described in Patent Document 1, 112 Axial groove described in Patent Document 1, 120 Shaft described in Patent Document 1.

Claims (6)

A paper feed roller having a number of grooves on a cylindrical surface,
The cylindrical surface is divided into first, second and third regions in order along the axial direction of the paper feed roller by a boundary line extending in the circumferential direction of the paper feed roller;
Each region is formed with a plurality of axial grooves extending along the axial direction along the entire length of each region,
The axial groove of the second region is located in a circumferential direction with respect to the axial groove of the first region and the third region,
A paper feed roller in which a circumferential groove extending in a circumferential direction is formed at a boundary portion of each region.   2. The paper feed roller according to claim 1, wherein the axial groove in the first region and the axial groove in the third region are provided so as to be positioned on the same axis.   The paper feed roller according to claim 2, wherein the patterns of the axial grooves and the circumferential grooves in the first, second, and third regions are symmetrical with respect to a line that passes through the center of the second region. .   The paper feed roller according to any one of claims 1 to 3, wherein a depth of the circumferential groove is larger than a depth of the axial groove. The cylindrical surface has fourth and fifth regions so as to sandwich the first, second and third regions,
In the fourth region and the fifth region, a plurality of axial grooves extending the entire length of each region are formed,
The circumferential groove | channel extended in the circumferential direction is formed in the boundary part of the said 1st area | region and the said 4th area | region, and the boundary part of the said 3rd area | region and the said 5th area | region, respectively. The paper feed roller according to any one of 1 to 4.   6. The paper feed roller according to claim 5, wherein the axial groove in the fourth region and the axial groove in the fifth region are positioned on the same axis as the axial groove in the second region.

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