JP2004331248A - Rotary conveyance member, sheet conveyance device, and image forming apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To prevent the occurrence of vibration and noise in a sheet conveyance device provided in an image forming apparatus. <P>SOLUTION: A feeding roller (rotary conveyance member) 20 has a roller shape, is made of rubber, is provided with a plurality of channels 47 formed in the direction of width at a fixed interval on a peripheral face, and is provided like knurl. A separation member 43 is energized by a separation energizing member to press a pressing projecting part 50 against the peripheral face of the feeding roller to form a nip. Sheet materials are put in the nip by rotating the feeding roller and are separated one by one for conveyance in this sheet conveyance device. A bridge part 49 crossing the channels is provided on the peripheral face of the feeding roller. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to an image forming apparatus for forming an image on a sheet material such as paper and an OHP film, such as a copier, a printer, a facsimile, or a composite machine thereof. In addition, the present invention relates to a sheet conveying device that conveys a sheet material in such an image forming apparatus. Also, the present invention relates to a rotary transport member that transports a sheet material provided in such a sheet transport apparatus.
[0002]
[Prior art]
For example, an electrophotographic copying machine includes an image reading device, an image forming device, a sheet conveying device, and the like. Then, after reading the content of the document with the image reading device, a toner image is formed on the image carrier of the image forming device based on the content of the document. At the same time, the sheet material is conveyed to the image forming device by the sheet conveying device, and thereafter, the toner image formed on the image carrier is transferred to form an image on the sheet material.
[0003]
In a sheet conveying device provided in such an image forming apparatus, a feeding roller is provided as a rotary conveying member that rotates and conveys a sheet material, and the rotation of the feeding roller causes a sheet to be placed in a sheet cassette or on a sheet tray. 2. Description of the Related Art There is a sheet feeding device that separates and transports stacked sheet materials one by one. 9 and 10 show an example of the sheet feeding device.
[0004]
The sheet feeding device includes a bottom plate 7 on which the sheet material S is placed and stacked, a feeding roller 8 that contacts the loaded sheet material S and feeds out the sheet material S, and a separating member 9 that presses the sheet material S against the sheet material S. And so on.
[0005]
A feeding force member (not shown) is provided on the bottom plate 7, and is urged upward as indicated by an arrow in the figure to press the stacked sheet materials S against the feeding roller 8.
[0006]
The feed roller 8 was made of rubber and provided with a plurality of grooves 8a formed in the circumferential surface over the width direction.
[0007]
The separation member 9 includes a shaft portion 9a at a base portion and a convex portion 9b at a tip portion. The pressing projection 9b has a top surface 9c that presses against the peripheral surface of the feeding roller 8, and an inclined surface 9d that is provided on the front end side surface. A pivoting member 9 is provided rotatably about the shaft portion 9a, and a separation urging member (not shown) is provided. Had formed.
[0008]
Then, the feeding roller 8 is rotated counterclockwise as indicated by an arrow in the drawing to feed out the sheet material S, and the fed out sheet material S abuts against the inclined surface 9c of the separating member 9; Through the nip between the sheet and the top surface 9c.
[0009]
[Problems to be solved by the invention]
However, since the separating member 9 is pressed against the feeding roller 8, the corner 9e of the separating member 9 abuts against a groove edge 8b located downstream of the groove 8a of the feeding roller 8 in the rotation direction, and generates vibration. There was a problem to do.
[0010]
The vibration is generated each time the corner portion 9e hits the groove edge 8b. Then, the vibration is transmitted to the sheet material S, the sheet feeding roller 8, the separating member 9, and the like, and then transmitted to various parts, thereby generating an unpleasant sound, which has been a problem.
[0011]
Accordingly, a first object of the present invention is to eliminate the occurrence of vibration and noise in a sheet conveying device.
[0012]
A second object of the present invention is to reduce the number of parts and simplify the configuration.
[0013]
A third object of the present invention is to prevent a foreign material such as paper dust from adhering to the rotary conveyance member and causing the sheet material to slip.
[0014]
A fourth object of the present invention is to more reliably prevent the sheet material from slipping.
[0015]
By the way, the feeding roller 8, which is a rotary conveying member, is often formed by pouring a liquid resin into a mold, forming the resin, and then taking out the resin from the mold.
[0016]
Therefore, a fifth object of the present invention is to improve the yield of the rotary conveying member when forming by using a mold in this way.
[0017]
A sixth object of the present invention is to provide a sheet conveying apparatus provided with a rotary conveying member that achieves the first to fifth objects.
[0018]
A seventh object of the present invention is to provide an image forming apparatus including a sheet conveying device that achieves the sixth object.
[0019]
[Means for Solving the Problems]
Therefore, the invention described in claim 1 aims to achieve the first object described above.
It is characterized in that a groove formed in the width direction is provided on the peripheral surface, and a bridge portion crossing the groove is provided.
[0020]
The invention described in claim 2 is to achieve the second object described above.
The rotary conveying member according to claim 1,
It is characterized by a roller shape.
[0021]
The invention according to claim 3 achieves the third object described above,
The rotary conveying member according to claim 1 or 2,
It is characterized by having a plurality of grooves.
[0022]
The invention according to claim 4 achieves the fourth object described above,
The rotary conveyance member according to claim 3,
It is characterized in that the bridge portion is provided for each groove so as to be sequentially shifted in the width direction.
[0023]
The invention described in claim 5 achieves the fourth object described above,
The rotary conveying member according to any one of claims 1 to 4,
A plurality of concave portions are dispersedly provided on the peripheral surface, and the peripheral surface is formed in a grain shape.
[0024]
The invention according to claim 6 achieves the fifth object described above,
The rotary conveying member according to any one of claims 1 to 5,
The side surface of the bridge is inclined outward.
[0025]
The seventh aspect of the present invention is to achieve the sixth object described above.
A sheet conveying apparatus, comprising: the rotary conveying member according to any one of claims 1 to 6; and a separating member that contacts the rotary conveying member, and separates and conveys a sheet material.
[0026]
The invention described in claim 8 achieves the seventh object described above,
An image forming apparatus comprising the sheet conveying device according to claim 7.
[0027]
BEST MODE FOR CARRYING OUT THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 shows an overall schematic configuration of an internal mechanism in an electrophotographic copying machine. Reference numeral 10 in the figure denotes a copying machine main body including an image reading device 11 on the inside.
[0028]
A drum-shaped image carrier 12 is rotatably provided substantially at the center of the copier main body 10. Around the image carrier 12, a developing device 14, a transfer device 15, a cleaning device 16, and the like are arranged in order from a charging device 13 disposed thereon in a rotation direction indicated by an arrow of the image carrier 12. An optical writing device 17 is provided on the image carrier 12.
[0029]
The image forming apparatus B is constituted by the image carrier 12 and the devices 13, 14, 15, 16, 17 and the like.
[0030]
A fixing device 18 is provided on the left side of the image forming device B in the drawing. The fixing device 18 includes, for example, a fixing roller 18A having a built-in heater as a heat source, and a pressure roller 18B pressing the fixing roller 18A from below.
[0031]
In the copying machine main body 10, a sheet conveying device C is provided below the image forming device B and the fixing device 18. The sheet conveying device C forms a sheet conveying path R that extends upward from the bottom in the figure, turns left upward, passes through the transfer position between the image carrier 12 and the transfer device 15, and further extends to the left. Then, the sheet material S such as paper and OHP film is conveyed through the sheet conveying path R.
[0032]
In the sheet transport path R, a feed roller (rotary transport member) 20 that sequentially feeds the sheet materials S in the sheet cassette 19 one by one from a sheet cassette 19 in which the sheet materials S are stacked and stored is sent out. A sheet transport roller 21 for transporting the sheet material S, a registration roller 22 for abutting and stopping the leading end of the sheet material S, a belt transport device 23 for transporting the sheet material S after image transfer to the fixing device 18, a sheet after image fixing. A discharge roller 24 for discharging the material S is provided.
[0033]
On the left side of the apparatus main body 10 in the figure, a paper discharge tray 25 for receiving the sheet material S discharged by the discharge roller 24 is detachably attached.
[0034]
Further, a double-sided device 26 is provided on the sheet cassette 19 in such a copying machine main body 10. At the exit of the fixing device 18, the sheet is guided to the double-sided device 26 through a reversing path R <b> 1 provided by branching from the sheet conveying path R. Further, from the double-sided device 26, a re-supply path R2 which joins the sheet conveyance path R at a position upstream of the sheet conveyance roller 21 is formed.
[0035]
The image reading apparatus 11 provided inside the apparatus main body 10 includes a light source 30, a plurality of mirrors 31, an imaging lens 32, an image sensor 33 such as a CCD, and the like.
[0036]
A contact glass 35 is provided on the upper surface of such an image reading device 11. A sheet holding plate 36 is provided on the contact glass 35 so as to be freely opened and closed.
[0037]
Now, when making a copy using the illustrated copying machine, the main switch (not shown) is turned on, the sheet holding plate 36 is opened, and the original is directly set on the contact glass 35. And close the original with it.
[0038]
Then, when a start switch (not shown) is pressed, the image reading device 11 is driven immediately, the light source 30 is turned on, the light from the light source 30 is reflected on the document surface, and the reflected light is reflected by a plurality of mirrors 31. Then, the light is guided to an image sensor 33 through the imaging lens 32, and the image sensor 33 converts an optical signal into an electric digital signal to read the contents of the document.
[0039]
At the same time, in the image forming apparatus B, the image carrier 12 is rotated clockwise as indicated by an arrow, the surface of the image carrier 12 is uniformly charged by the charging device 13, and then read by the image reading device 11. Based on the digital image signal corresponding to the read content, a laser beam L is applied to write by the optical writing device 17 to form an electrostatic latent image on the surface of the image carrier 12. The electrostatic latent image adheres to the toner, and the electrostatic latent image is visualized to form a toner image.
[0040]
At the same time when the start switch is pressed, in the sheet conveying apparatus C, the feed roller 20 is rotated, the sheet material S stored in the sheet cassette 19 is sent out, put into the sheet conveying path R, and conveyed by the sheet conveying roller 21. Then, it stops against the registration roller 22. Then, the registration roller 22 is rotated in synchronization with the toner image on the image carrier 12, and is sent below the image carrier 12.
[0041]
Then, the toner image on the image carrier 12 is transferred by the transfer device 15 at the transfer position to the sheet material S sent below the image carrier 12. After transfer of the image, the image carrier 12 is cleaned with a cleaning device 16 to remove the residual toner, and the surface is cleaned to prepare for the next similar image formation.
[0042]
On the other hand, the sheet material S after the image transfer is conveyed by the belt conveying device 23 and enters the fixing device 18, where heat and pressure are applied by the fixing roller 18A and the pressing roller 18B to fix the transferred image. Thereafter, the sheet is discharged onto a discharge tray 25 by a discharge roller 24.
[0043]
When an image is formed on both sides of the sheet material S, the sheet is put into the reversing path R1 from the sheet conveying path R, is reversed by the duplex apparatus 26, is conveyed by the re-conveying roller 27, and is conveyed again through the re-feeding path R2. The toner image formed on the image carrier 12 is transferred onto the back surface of the sheet material S on the path R, and the transferred image is fixed by the fixing device 18 and discharged to the discharge tray 25.
[0044]
FIG. 2 is an enlarged view of a sheet feeding device which is a part of the sheet conveying device C in the above-described copying machine.
Reference numeral 40 in the figure denotes a feeding housing. The feeding housing 40 supports a roller shaft 41 of the feeding roller 20 which is a rotary conveying member.
[0045]
The separation urging member 42 urges the peripheral surface of the feeding roller 20 to press the leading end of the separation member 43. The separation member 43 has a lever shape, and is rotatably supported by a member (not shown) about the shaft portion 44 of the base.
[0046]
Further, a bottom plate 45 is provided in the above-described sheet cassette 19, and the sheet material S is stacked and stored on the bottom plate 45. In the sheet cassette 19, the bottom plate 45 is pushed up by being urged by the feeding urging member 46, and the leading end of the uppermost sheet material S of the stacked sheet materials S is pressed against the peripheral surface of the feeding roller 20.
[0047]
FIG. 3 is an enlarged view of the leading end of the separation member 43 pressed against the feed roller 20. FIGS. 4A to 4D show the feeding roller 20. FIGS. 5A to 5C show the shapes of various grooves 47 provided on the peripheral surface of the feeding roller 20. FIG. 6 shows a part of the peripheral surface of the feed roller 20 in an enlarged manner.
[0048]
As can be seen from FIGS. 3 and 4, the feed roller 20 has a roller shape, is made of rubber, and is provided with a plurality of grooves 47 formed in the circumferential direction on the peripheral surface at regular intervals, for example, and is knurled. It is provided in a shape. The groove 47 may have a rectangular cross section as shown in FIGS. 3 and 4C, a V-shape as shown in FIG. 5A, or a U-shape as shown in FIG. Or a trapezoidal shape as shown in FIG. Further, as shown in FIG. 6, a plurality of shallow concave portions 48 are preferably provided on the peripheral surface of the feeding roller 20 in a distributed manner, and are formed in a grain shape.
[0049]
In addition, as shown in detail in FIG. 4, a bridge portion 49 crossing the groove 47 is provided on the peripheral surface of the feeding roller 20 with which the separating member 43 contacts, flush with the peripheral surface. In the illustrated example, bridge portions 49 are provided side by side on the three circumferences of the feeding roller 20 in the width direction. The side surface 49a of the bridge portion 49 is, for example, vertical.
[0050]
Further, as shown in FIG. 3, a pressing projection 50 is provided at the tip of the separation member 43 so as to protrude toward one surface side along the edge. The pressing convex portion 50 has a top surface 51 that presses against the peripheral surface of the feeding roller 20 and an inclined surface 53 that is provided on a front end side surface.
[0051]
Then, the feeding roller 20 is rotated in the direction of arrow D to sequentially feed out the stacked sheet materials S from above, and the leading end of the sheet material S conveyed by the feeding roller 20 is abutted against the inclined surface 53, and the feeding roller 20 is rotated. The sheet material S is guided to a nip between the peripheral surface of the separation member 20 and the top surface 51 of the separation member 43, and the sheet material S is separated one by one at the nip and transported in the direction of arrow A in FIG.
[0052]
As shown in FIG. 3, by forming the inclined surface 53 on the separation member 43, it is possible to prevent the generation of abnormal noise and to prevent the non-feeding caused by the curl of the sheet material S or the burr of the cut surface. Occurrence can be prevented.
[0053]
Further, since a bridge portion 49 crossing the groove 47 is provided on the peripheral surface of the feed roller 20 with which the separation member 43 comes into contact, the tip of the separation member 43 moves on the bridge portion 49 when the feed roller 20 rotates. As a result, it is possible to prevent the feeding roller 20 from entering the groove 47 and to eliminate the generation of vibration and noise generated from the separation member 47.
[0054]
Further, by forming a plurality of grooves 47 on the peripheral surface of the feeding roller 20 and providing the concave portions 48 in a crimped shape, foreign substances such as paper dust adhered to the peripheral surface of the feeding roller 20 can be removed. It is possible to prevent the sheet material S from slipping due to the inclusion of foreign matter in the grooves 47 and the concave portions 48 with rotation.
[0055]
In the example of the feed roller 20 described above, an example is shown in which the bridge portions 49 are provided side by side on three circumferences in the width direction. However, the present invention is not limited to this. For example, the feed roller shown in FIG. As in 55, the bridge portions 49 may be provided for each groove 47 so as to be sequentially shifted in the width direction of the feed roller 55.
[0056]
In this way, the foreign matter adhering to the bridge portion 49 can be inserted into the groove 47 downstream in the rotation direction with the rotation of the feeding roller 55, and the slip of the sheet material S due to the presence of the foreign matter can be prevented. Can be prevented.
[0057]
Further, in the above-described feed rollers 20 and 55, the side surface 49a of the bridge portion 49 is made vertical, but the present invention is not limited to this. For example, like the feed roller 56 shown in FIG. May be inclined outward.
[0058]
In this way, when the feed roller 56 is produced, the bridge portion 49 is damaged when a mold is used, the liquid resin is poured into the mold, molded, and removed from the mold. Therefore, the yield of the feed roller 56 can be improved when forming by molding using a mold.
[0059]
In the above-described example, the case has been described in which the rotary conveying member is a roller-shaped feeding roller. However, the present invention is not limited thereto, and the rotary conveying member may be a belt.
[0060]
Further, the present invention is not limited to the above-described configuration, and is applicable to other sheet feeding apparatuses. That is, the present invention may be applied to a sheet feeding apparatus of a separation pad type in which a separation pad is pressed against a feeding roller or a bank separation type in which a guide plate is provided at a sheet feeding position.
[0061]
【The invention's effect】
As described above, according to the first aspect of the present invention, since the circumferential surface is provided with the groove formed in the width direction and the bridge portion is provided to cross the groove, the separation presses against the rotary conveyance member when rotating. The member can be moved on the bridge portion, the separating member can be prevented from entering the groove of the rotary conveyance member, and the generation of vibration and noise caused by the entering of the separating member can be eliminated.
[0062]
According to the second aspect of the present invention, since it has a roller shape, the number of components can be reduced and the configuration can be simplified.
[0063]
According to the third aspect of the present invention, since a plurality of grooves are provided, foreign matter such as paper dust adhered to the peripheral surface of the rotary conveyance member can be put into the groove downstream in the rotation direction with rotation of the rotary conveyance member. Further, slippage of the sheet material due to the presence of foreign matter can be prevented.
[0064]
According to the fourth aspect of the present invention, since the bridge portions are sequentially shifted in the width direction for each groove, the foreign matter attached to the bridge portion is put into the groove downstream in the rotation direction with the rotation of the rotary conveyance member. It is possible to more reliably prevent the sheet material from slipping due to the presence of the foreign matter.
[0065]
According to the invention according to claim 5, a plurality of recesses are dispersedly provided on the peripheral surface and the peripheral surface is formed in a crimped shape. This can more reliably prevent the sheet material from slipping.
[0066]
According to the invention according to claim 6, since the side surface of the bridge portion is inclined outward, at the time of production of the rotary transport member, using a mold, after pouring and molding a liquid resin into the mold, Since it is possible to prevent the bridge portion from being damaged when it is taken out from the mold, it is possible to improve the yield of the rotary conveyance member when forming the mold by using the mold.
[0067]
According to a seventh aspect of the present invention, there is provided a sheet conveying apparatus comprising the rotary conveying member according to any one of the first to sixth aspects and a separating member abutting on the rotary conveying member to separate and convey the sheet material. Since the apparatus is an apparatus, it is possible to provide a sheet conveying apparatus including the rotary conveying member having the above-described effects.
[0068]
In addition, since such a sheet conveying device can convey even if there is a burr on the cut surface, it is possible to convey it in a good manner, to relatively reduce abrasion, to improve durability, and to make the configuration simple and compact. can do.
[0069]
According to the eighth aspect of the present invention, since the image forming apparatus includes the sheet conveying apparatus according to the seventh aspect, it is possible to provide an image forming apparatus including the sheet conveying apparatus having the above-described effects.
[Brief description of the drawings]
FIG. 1 is an overall schematic configuration diagram of an internal mechanism in an electrophotographic copying machine.
FIG. 2 is an enlarged view showing a sheet feeding device which is a part of a sheet conveying device in the copying machine.
FIG. 3 is an enlarged configuration diagram of a leading end portion of a separation member provided in the sheet feeding device.
FIGS. 4A and 4B show a feeding roller provided in the sheet feeding apparatus, wherein FIG. 4A is a side view, FIG. 4B is a front view, FIG. 4C is an enlarged view of a portion f, and FIG. It is.
FIGS. 5A to 5C are partial enlarged views of a feeding roller showing various groove shapes provided on a peripheral surface.
FIG. 6 is a partially enlarged perspective view of a peripheral surface of a feeding roller.
7A and 7B show another example of the feeding roller, wherein FIG. 7A is a side view, FIG. 7B is a front view, FIG. 7C is an enlarged view of an f section, and FIG. .
FIGS. 8A and 8B show another example of the feeding roller, wherein FIG. 8A is a side view, FIG. 8B is a front view, FIG. 8C is an enlarged view of a portion f, and FIG. is there.
FIG. 9 is a configuration diagram of a conventional sheet feeding apparatus.
FIG. 10 is an enlarged perspective view of a distal end portion of a separation member provided in the sheet feeding device.
[Explanation of symbols]
20, 55, 56 Feeding roller (rotary conveying member)
43 separation member 47 groove 48 concave portion 49 bridge portion 49b side surface C sheet conveying device S sheet material

Claims (8)

A rotary conveying member comprising a groove formed on a peripheral surface in a width direction, and a bridge portion crossing the groove. The rotary conveyance member according to claim 1, wherein the rotation conveyance member has a roller shape. The rotary conveyance member according to claim 1, wherein a plurality of the grooves are provided. The rotary conveying member according to claim 3, wherein the bridge portion is provided for each of the grooves so as to be sequentially shifted in a width direction. The rotary conveying member according to any one of claims 1 to 4, wherein a plurality of concave portions are provided on the peripheral surface in a distributed manner, and the peripheral surface is formed in a crimped shape. The rotary conveying member according to any one of claims 1 to 5, wherein a side surface of the bridge portion is inclined outward. A sheet conveying apparatus comprising: the rotary conveying member according to claim 1; and a separating member that contacts the rotary conveying member, and separates and conveys a sheet material. An image forming apparatus comprising the sheet conveying device according to claim 7.

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