JP2002240979A - Imaging device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To solve the problem generating a slide friction noise by slide rubbing a paper sheet closely pressed to a guide member in the case of pulling the paper sheet by a conveying means in a curved part of a paper conveying path, generating paper powder by finely peeling an obverse of the paper sheet due to slide friction, wearing a protrusion or the like formed in a surface of a guide member to be partially consumed, and so on. SOLUTION: This device is characterized by providing a paper guide means 81, 82 in a paper conveying path between a paper feed means feeding the paper sheet from a paper storage tray and a conveying means for conveying the paper sheet to a recording part, having a guide surface 81a-c abutting to the paper sheet in the paper guide means 81, 82, and providing a resin sheet member 90 in this guide surface. In this way, the paper sheet conveyed by the conveying means, in the case of conveying along a conveying guide, is friction slide with a resin sheet, generation of a slide friction noises and paper powder is reduced, additionally shaving of the guide surface in a guide member is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] 1. Field of the Invention [0002] The present invention relates to an image forming apparatus provided with a sheet conveying means such as a copying machine, a printer, and a facsimile.

[0002]

2. Description of the Related Art In an image forming apparatus such as a copying machine, a printer, a facsimile, or the like, a sheet stored in a sheet storage tray is transported to a transport recording unit by a paper feeding unit, and an image is formed thereon. ing. In recent years, paper feeders are often provided with a paper storage tray below the recording unit from the viewpoint of miniaturization and space saving in these apparatuses. In these apparatuses, the paper transport path has a structure that starts from the paper supply side of the paper storage tray and curves and extends in a vertical direction or a reverse direction. Therefore,
The sheet sent from the sheet storage tray by the sheet feeding means is conveyed to conveying means such as a pair of registration rollers along the curved portion of the sheet conveying path. When the paper is conveyed downstream by the conveyance means, the paper supply means is driven by retracting the paper supply roller of the paper supply means or canceling the drive in order to prevent the next paper from being conveyed in a multilayered manner. You will be in a state to do. The paper transport path is generally composed of guide members disposed opposite to each other at a predetermined interval, and when the paper is pulled by the transport unit, the paper slide path rubs against the guide member inside the curved transport path. While moving.

The guide member has a high degree of freedom in the shape of the guide in the transport direction and the width direction, and it is easy to provide a projection on the surface for reducing the contact area with the paper. Is often used. Further, in these image forming apparatuses, a member formed of a resin material may be used as a structural member of the main body in order to reduce the size and weight and reduce the number of parts. In particular, in a device intended for individual users, it is important that the device is small, lightweight and inexpensive, so that a resin member is often used. In these resin-molded structural members and the like, in addition to the structural function of supporting the recording portion and the like, the shape for attaching parts and the entire or partial shape of the inner guide plate and the outer guide are integrally formed. Molding is being done.

[0004]

In an apparatus for forming an image by transporting a sheet in the apparatus as described above, in addition to the transport performance of the sheet, the guide member and the sheet slide on a curved portion of the sheet transport path. There are some problems caused by: Specifically, when the sheet is pulled by the conveying means in the curved portion of the sheet conveying path, the sheet is strongly pressed against the guide member and rubs, so that a rubbing sound is generated,
There is a problem that the paper surface is minutely peeled off by rubbing and the paper powder is generated, and a projection formed on the surface of the guide member is worn out and partially disappears. The rubbing noise is a major cause of noise during use of the apparatus, and is a major problem in small-sized apparatuses with particularly strict noise standards because the ratio of the rubbing noise tends to increase as a factor of noise. In addition, the generation of paper dust causes dirt in the apparatus and adheres to various parts, causing a problem. In the conveying means, the frictional force on the surface of the roller or friction member is reduced to cause paper conveyance failure, the detection switch does not function properly due to dirt, and the recording unit causes image failure or recording. This may cause problems such as shortening the life of the part. Further, when the guide member is worn, the rubbing state of the paper changes, causing a problem in the paper transport performance,
And increase the generation of rubbing noise and paper dust. For this reason, conventionally, a means for removing and collecting paper dust on the paper has to be provided, and maintenance such as cleaning is periodically required, which has caused extra labor and cost.

[0005]

SUMMARY OF THE INVENTION The present invention provides an inexpensive and effective method for solving the above problems. According to the first aspect of the present invention, a sheet storage tray is disposed below a recording unit that performs recording on sheets, and a sheet feeding unit, a sheet conveyance path, and a conveyance unit for conveying the sheets in the sheet storage tray to the recording unit are provided. In the image forming apparatus, a paper guide is provided in a paper transport path between a paper feeder for feeding paper from a paper storage tray and a transporter for transporting paper to a recording unit, and the paper guide is in contact with the paper. And a resin sheet member is provided on the guide surface. With this, the paper conveyed by the conveyance means rubs against the resin sheet when being conveyed along the conveyance guide, so that the rubbing noise and the generation of paper dust are reduced and the guide surface of the guide member is scraped. Is prevented.

According to a second aspect of the present invention, a sheet having a thickness of 0.1 to 0.3 and made of polyethylene as a resin sheet is attached to the guide surface with an adhesive. Thereby, the effect of reducing the rubbing noise and the generation of paper dust can be further enhanced. In addition, durability against abrasion is increased, and a long life can be achieved.

According to a third aspect of the present invention, a detection switch for detecting passage of a sheet is provided on the guide surface of the guide member. Since the amount of paper dust generated from the use on the guide surface is reduced, the risk that the optical sensor of the detection switch becomes dirty and malfunctions are reduced. This makes it possible to dispose the detection switch even in a curved portion where paper dust is likely to be generated, so that it is possible to save space in the paper transport path and to reduce the size of the apparatus.

According to a fourth aspect of the present invention, the conveyance means is a registration roller, the paper supply means is a half-moon roller, the paper conveyance path is curved between the registration roller and the half-moon roller, and the detection switch is It is characterized in that it also serves to detect whether paper is fed from the half-moon roller and to detect registration timing. This reduces noise and paper dust, reduces the size of the device by arranging the paper transport path on the side of the device with the paper storage tray below, and reduces costs by using the detection switch. Also becomes possible.

According to a fifth aspect of the present invention, the paper storage tray is supported by a structural member formed of a resin material, and the guide surface is formed integrally with the structural member. Accordingly, it is possible to reduce the generation of noise and paper dust and to reduce the cost by unifying the guide member by integrally forming the guide surface with the structural member.

According to a sixth aspect of the present invention, the guide surface is formed so as to have a convex shape near the center in the width direction with respect to the paper transport direction, and the upstream side of the curved portion in the paper transport direction over a certain width than the both sides thereof. The opening of the detection switch is provided on the convex portion, and the sheet member is provided on the convex portion other than the opening. Accordingly, when the paper fed from the paper storage tray is transported by the transporting means, the vicinity of the center of the upstream portion of the guide surface with which the paper comes into contact has a convex shape. And the generation of noise and paper dust is further reduced. Further, in a portion of the guide surface where the curvature is small on the downstream side, the paper and the guide surface are in contact with the entire surface in the width direction of the paper transport direction, so that the transport of the paper by the transport means can be appropriately guided.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described.
This will be described in detail with reference to the drawings. FIG. 1 is a schematic view of a copying apparatus 1 to which the present invention is applied as an example of an image forming apparatus.
FIG. 2 is a schematic diagram showing the structure of the copying apparatus 1. The copying apparatus 1 has a lower base 2, an image forming frame 3, a scanner device 4, and a reinforcing member 5 connected to each other to form a structural member of an apparatus main body. An outer cover, a paper storage tray, a document conveying device, and the like are attached thereto. Have been. The base 2 is a rectangular molded product using a resin material. The lower portion is formed with a structural member on a U-shape, and the grounding portions 2a for installing the device thereon are provided near the four corners. I have. A paper storage tray 6 is detachably mounted in a space inside the base 2.
The image forming frame 3 is also a molded article of resin and houses an image forming unit for forming an image on paper. Base 2
As the resin material of the image forming frame 3, a material containing about 20% of glass fiber in the most commonly used ABS resin in order to improve strength and dimensional accuracy is used. The scanner device 4 is a rectangular box-shaped sheet metal member having an upper opening, and a contact glass 9 is provided in the opening.
Are mounted, and an optical component and an electric component are arranged inside.

FIG. 3 is a schematic sectional view showing the internal configuration of the copying apparatus 1 shown in FIGS. In the scanner device 4 of the copying apparatus 1, a transparent contact glass 9; a scanning unit 20 below the transparent contact glass 9 for exposing the original while moving the original surface; a reflecting mirror 21 for reflecting and guiding the original image; A lens unit 22 for forming a document image and a CCD 23 for converting document information into an electric signal are provided. Above the scanner device 4, a document feeder 7 is hinged at the rear (rear side in FIG. 3), and is pivotally mounted at a position facing the contact glass 9 and at a position where it is opened. The document feeder 7 has a function of pressing a document on the contact glass 9 and a function of automatically feeding and reading a sheet document.

The printing section 13 is disposed substantially at the center in the vertical direction on the left side in FIG.
And a cylindrical photoconductor (hereinafter, referred to as “photoconductor drum”) 30. The photoreceptor drum 30 is rotatably supported by the copying machine main body 11 in the direction of the arrow (clockwise in the figure), and the primary charger 31, the exposing device 32, A developing device 33, a transfer charger (transfer roller) 34, and a cleaning device 35 are provided. Components other than the transfer charger 34 are integrated as an image forming unit, and can be attached to and detached from the image forming frame 3 from the front.

The exposing device 32 has a laser oscillator, a polygon mirror and the like (both not shown), and forms an electrostatic latent image on the surface of the photosensitive drum 30. The image information of the document read by the reader unit 12 is subjected to appropriate processing such as A / D conversion, density correction, and shading correction by an image processing unit (not shown) provided in the print unit 13. Then, it is input to the laser oscillator as an image signal. The laser oscillator exposes the charged surface of the photosensitive drum 30 through a polygon mirror or the like with a laser beam that is turned on / off based on the image signal.
An electrostatic latent image is formed by removing charges from the exposed portion.

A transfer roller 34, which is a transfer charger, is swingably attached to a transfer unit 40 which is attached to the left side of the image forming frame 3 and can be opened and closed about a lower fulcrum. Numeral 34 denotes a positioning roller inserted at both ends of the roller shaft, which is in contact with the surface of the drum, and is arranged with an appropriate gap maintained. A gear is inserted into one end of the transfer roller shaft, meshes with a drive gear on the main body side when closed, and rotates at the same peripheral speed as the surface speed of the photosensitive drum 20.

A transport guide 42 for guiding the sheet after the transfer of the toner image to the fixing device 43 is provided downstream of the transfer roller 34. The fixing device 43 has a fixing roller 51 heated by a heater 50 disposed inside, and a pressure roller 52 for pressing a sheet against the fixing roller 51, and carries an unfixed toner image on the surface. The paper conveyed is heated and pressed to fix the toner image on the surface of the transfer material P. The sheet that has passed through the fixing device 43 is discharged onto a sheet discharge tray 54 by a discharge roller 53.

Next, the sheet conveying means in the copying apparatus 1 will be described. The sheets are stored in a sheet storage tray 6, and a water supply unit 6 that feeds the sheets one by one is provided above the tray.
0 is provided. The paper fed by the paper feeding means 60 advances along the paper transport path 61, and the leading end of the paper comes in contact with the downstream registration roller 62 at the nip portion. A detection switch 63 for detecting the leading edge and the trailing edge of the passing paper is provided in the middle of the paper transport path 61. The registration roller 62 conveys the sheet toward the transfer section of the photosensitive drum 30.

The paper storage tray 6 is made of a resin material and is formed in a rectangular box shape with an upper opening, and a width regulating member 71, a front claw member 72, a lift plate 73, and an urging member provided inside the case 70. The means 74 comprises a rear end regulating member 75. The width regulating member 71 has an upright wall 71a extending in the paper transport direction, and is arranged in parallel with an interval in the front-rear direction. It is growing towards. The arm portion is supported on the bottom surface of the case 70 so as to be slidable in the front-rear direction, and is connected via a pinion to interlock. When one of the width regulating members is moved, the other also moves in the direction away from or away from each other by the same distance. A claw member 72 is supported by each width regulating member 71 at a fulcrum 72a so as to be swingable within a specified range. The claw member 72 is formed of sheet metal, has a wall on the left side, and has an upper end bent horizontally to form a claw portion 72b. The lift plate 73 is swingably supported by fulcrums 73a provided on the front and rear walls of the case 70, and is urged upward by urging means 74 disposed below. The paper rear end regulating member 75 has an upright wall 75 a extending in the front-rear direction, and is slidably engaged with a groove formed in the left-right direction near the center in the front-rear direction of the case 70. The width regulating member 71 and the rear end regulating member 75 are moved according to the size of the paper to be stored. When storing the paper, if the paper is pushed in against the urging force of the lift plate, the leading edge of the paper urged upward by the lift plate is pressed by the claw portion 72b whose swing is restricted to a certain range. Therefore, the upper end of the stored paper is maintained at a constant height regardless of the amount of paper. The width direction of the paper is a width regulating member 71, and the leading end is a wall 72 of a claw member 72
d, the rear end is regulated by the rear end regulating member 75, respectively.

The sheet storage tray 6 has a projection 70a extending in the horizontal direction on the left and right side walls of the case 70, and is mounted through an opening in the front of the base 2. Base 2
A concave portion 2b extending in the front-rear direction is formed on the left and right side wall portions in accordance with the protrusion 70a on the outer wall of the case 70, and the case 70 is inserted using the concave portion 2b as a guide rail.

At the upper left side of the base 2, a paper feed roller 80 in which two half-moon rollers are coaxially arranged at an interval in the front-rear direction is attached. The semicircular roller has a shape in which a part of the circumference is cut, and a friction member such as a rubber material is formed on the remaining circumference. A spring clutch is inserted into the shaft of the paper feed roller, and driving is input by a gear through the spring clutch. An engaging portion is provided at a predetermined position in a circumferential direction of an outer frame portion of the spring clutch, and a swingable operating piece to which a solenoid is connected is engaged with the projection. When the operating piece is engaged with the engaging portion of the outer frame portion to stop the rotation, the internal spring is loosened and the drive is not transmitted to the shaft. When the solenoid is operated and the engagement of the operation piece is released, the internal spring is tightened, and the shaft and the outer frame part rotate integrally.
If the operating piece has returned to the original position, the engagement is engaged again and the rotation stops.

The paper feed roller 80 can be stopped at the same position in the circumferential direction, and can be controlled to make one rotation intermittently. When the cutout portion of the half-moon roller faces the paper stored in the paper storage tray 6, it can be controlled. It is set to stop. The paper feed roller 80 is separated from the paper in the paper storage tray 6 at the stop position, and is provided at a position where the circumferential surface abuts when rotated. When the paper feed roller 0 rotates, the circumferential portion abuts and feeds the paper in the rotational direction by the frictional force.
One sheet of the uppermost sheet is disengaged from the nail and is conveyed to the sheet conveying path 61.

Next, the sheet transport path 61 will be described. FIG. 4A is a cross-sectional view illustrating details of a sheet feeding unit and a sheet conveyance path. In the paper transport path 61, an outer guide surface 81 and an inner guide surface 82 are arranged to face each other with a gap, and extend in the vertical direction after being curved. Each guide member is formed integrally with the base 2 in the width direction in the paper transport direction. The lower guide surface 81 extends obliquely upward from a starting point 81a located below the paper to be fed, and has a front end portion behind the outer guide surface 81 in the width direction in the paper transport direction. It merges with the attached elastic resin flat sheet A83. Paper feed roller 8
The leading edge of the sheet conveyed by the sheet No. 0 is guided upward along the outer guide surface 81, and further guided upward by the resin sheet A83 further downstream.

FIG. 4B is an enlarged schematic view of the inner guide surface 82. As shown in FIG. FIG. 5 is a perspective view showing the portion where the inner guide surface 82 is integrally formed when the base 2 is viewed from the left side of the apparatus. When viewed in the cross-sectional direction, the inner guide surface 82 extends in a substantially horizontal direction from a starting point 82 a located slightly upstream of the leading end of the paper above the paper stored in the paper storage tray 6 adjacent to the paper feed roller 80. It comprises a substantially planar horizontal guide portion 82b extending, a curved portion 82c formed into a substantially R-shaped curved portion, and a substantially planar vertical guide portion 82d extending substantially vertically downstream of the curved guide portion 82c. However, in the horizontal guide portion 82b, the fixed width portion near the center in the width direction with respect to the paper transport direction is approximately 3 m downward with substantially the same shape from both sides.
A convex guide surface 82e is formed to protrude by about m. The convex guide surface 82e and the guide surfaces 82f on both sides thereof smoothly merge near the downstream side of the curved guide portion 82c when viewed in the cross-sectional direction, and have the same plane. The outer shape of the inner guide surface 82 shown in FIG. 4 indicates the outer shape of the convex guide surface 82e, and the outer cross-sectional shape of the guide surfaces 82f on both sides thereof is indicated by a broken line in FIG.

The width of the convex guide surface 82e is about 30 mm, and a detection switch 63 for detecting the leading edge and the trailing edge of the passing paper is provided on the back side of the paper guiding surface. The detection switch 63 has a detection piece 63a that is swingably supported at a fulcrum and an optical switch 63b. A detection opening 84 is provided from near the downstream of the curved portion 82c of the inner guide surface 82 to the vertical guide portion 83, and one arm of the detection piece 63a protrudes from the detection opening 84 so as to block the transport path. The transported sheet is the detection piece 63a.
When the arm A 63c is moved, the other integrally formed arm B 63d moves and the optical switch 63b is turned on or off.

A stepped portion that is slightly concave near the tip of the vertical guide portion 82d extends in the width direction with respect to the sheet conveying direction, and the resin sheet B85 is attached in the width direction except for the detection opening 84. I have. The resin sheet B85 has a flat shape having elasticity, and its tip is formed of a registration roller 6.
It extends to the vicinity of 2. Further, a resin sheet C86 is provided in a portion facing the vertical guide portion 82d in a width direction with respect to the sheet conveying direction. Resin sheet C86
Is a planar shape having elasticity, the upper side is inclined in a direction approaching the opposing surface side, the lower side is attached to the guide member, and the front end portion extends to a position close to a surface near the front end of the resin sheet B85. . Resin sheets A, B, C83, 8
Reference numerals 5 and 86 are for optimally guiding the paper to the registration rollers by utilizing elasticity, and have a thickness of 0.1 to 0.3 m.
m (polyethylene terephthalate) film is inexpensive and suitable as a material.

The starting portion 82 is provided on the surface of the convex guide surface 82e.
The sheet member 90 is provided from the position a to the step portion of the vertical guide portion 82d except for the detection opening 84. FIG.
(A) is a schematic diagram showing a state in which the sheet member 90 is attached to the convex guide surface 82. FIG. 6B shows the member shape of the sheet member 90. The sheet member 90 is attached to the convex guide surface 82e with a double-sided tape or an adhesive. As the sheet member 90, a material having a smooth surface and a low friction coefficient is suitable.
A supramolecular polyethylene sheet of about 0.3 mm is suitable. These are more expensive per unit area than the PET film, but have a low elasticity, so it is convenient to stick them along the shape of the curved portion. It is considered that a Teflon (registered trademark) sheet or the like is also effective as another sheet member.

Next, a description will be given of a sheet feeding control to the sheet storage tray 6 image forming section. FIG. 7 shows a timing chart of the sheet feeding control. At a timing T1 when the start button of the operation unit of the copying apparatus 1 is pressed, the motor starts rotating, and the image recording unit, the fixing device, and the like start rotating. At the same time as the start, the solenoid of the paper feed roller is turned on, the engagement between the operating claw and the spring clutch is released, and rotation starts, and after a while, the peripheral surface of the roller contacts the paper in the paper storage tray and feeds the uppermost paper I do. In FIG. 7, the hatched portion indicating the state of the sheet feeding roller indicates that the peripheral surface of the half-moon roller is in contact with the sheet. The fed paper is guided by the outer guide surface 81 and the resin sheets A, B, C83, 85, 86, and is conveyed toward the nip portion of the registration roller. On the way, the leading end of the sheet is detected by pressing the arm A63c of the detection switch 63 (timing T2). The registration roller is started at a timing T3 after a time t1 from the timing T2 when the leading edge of the sheet is detected. The time t1 is set slightly longer than the time when the leading edge of the sheet reaches the nip portion of the registration roller 62. As a result, the leading end of the sheet is aligned with the nip of the registration roller 62, so that the sheet can be conveyed downstream after correcting the inclination of the sheet in the conveying direction. The writing timing of the optical system is also set based on T2. At a timing T5, which is a fixed time t2 after the timing T4 when the trailing edge of the sheet conveyed by the registration rollers 62 has passed the detection switch 63,
The feeding of the second sheet is started, and the rotation of the registration roller 62 is stopped at a timing T6 after time t3 from T4 (time enough for the rear end of the sheet to pass through the nip portion of the registration roller 62), and The conveyance of the first sheet is completed.

Here, the registration roller 62 rotates and starts to convey the paper, and after a while, the circumferential portion of the half-moon roller of the paper feeding means is separated from the paper and the conveying force is lost. After that, the sheet is pulled by the registration roller 62, so that the sheet comes into contact with the guide surface 82 inside the sheet feeding conveyance path 61. At this time, the horizontal guide portion 82b and the curved guide portion 8
On the upstream side of 2c, since the convex guide surface 82e is in contact with the vicinity of the center of the sheet, the guide surfaces on both sides thereof do not contact the sheet. The convex guide surface 82e and a part on the downstream side of the curved guide portion 82c where the guide surfaces on both sides join together and the vertical guide portion 82
In d, the sheet comes into contact with the guide surface 82 over the entire surface in the width direction with respect to the transport direction. When the guide surface 82 comes into contact with the paper, the friction generates a rubbing sound or the fibers on the surface of the paper are peeled off, thereby generating paper dust. These generation levels are considered to be related to the contact area, the contact force between the paper and the guide surface, and the frictional force. Therefore, it is possible to reduce rubbing noise and paper dust by reducing these factors. Further, it is considered that the contact force is larger in the curved portion than in the flat portion of the guide surface, and is larger as the curve is more severe. In the case of the copying apparatus 1, the curved guide portion 82c has a convex guide surface 82 at the center.
e is formed, and the sheet member 90 having a low frictional resistance is provided in that portion, so that the contact area and the frictional resistance are reduced. In addition, by providing the convex guide surface 82e, it is possible to make the curvature of the portion on the guide surface gentler than the portions on both sides. In addition, there is an advantage that the space in which the detection switch 63 and the like are provided becomes wider due to the convex guide surface 82e, and the design becomes easier. Further, in the downstream portion of the curved guide portion 82d, the paper is in contact with the inner guide surface 82 on the entire surface, but is not curved so that a large frictional force is not generated. Properly maintained.

As described above, the convex guide surface 82e has the effect of properly transporting the fed paper and reducing the area where the paper rubs against the guide surface. Further, by providing the sheet member 90 in the portion of the convex guide surface 82e, it is possible to reduce the sliding noise at the time of paper feeding.
Further, it is effective that the width of the convex guide surface 82e in the width direction with respect to the paper transport direction is about 10 to 20% of the maximum width of the transported paper. If the width of the convex guide surface 82e is too small, the posture at the time of feeding the paper to the transport path becomes unstable, and the ears are likely to break, or the force acting on the paper when pulled by the downstream roller is reduced. The bias is increased and the paper is creased. Conversely, when the width is set to be large, adverse effects such as an increase in noise due to an increase in the rubbing surface and an increase in cost due to the provision of the sheet member 90 over a wide area occur.

In the copying apparatus 1, the maximum sheet to be conveyed is A4 size (sheet width in the conveying direction 210 mm), the processing speed during continuous copying is about 10 sheets of A4 sheet per minute, and the number of copies per month is relatively small. It is a low segment device intended for a small number of users. By practicing the present invention in the copying apparatus 1, it is possible to reduce the noise level estimated from the left side of the apparatus provided with the paper feeder by about 1 db in the noise evaluation during use of the apparatus, and the class to which this apparatus belongs JIS standard of 55 db or less was achieved. Further, the copying apparatus 1 is designed to extend the life of each system of the printing unit (photosensitive drum, developing device, etc.)
Throughout the life of the apparatus (equivalent to 100,000 sheets in A4 paper-based copy processing), it is an apparatus that does not require replacement of parts except for the replacement of toner cartridges that can be handled by the user, thereby improving economy and convenience. The present invention has a significant effect on solving the problems that make maintenance unnecessary such as improvement of durability of the conveyance guide surface generated by the above and cleaning due to dirt such as paper dust. As described above, the copying apparatus has been described as an embodiment, but the present invention can be used regardless of a printer, a facsimile, or the like as long as the apparatus has a similar sheet conveying unit, and the same effect is obtained. it is obvious.

[0031]

As described above, according to the present invention, it is possible to improve the performance and life by reducing the rubbing noise of the transport paper and the generation of paper dust without increasing the cost in the transport path having the curved portion. It is possible. Further, it is possible to make the design of the transport path compact, and this is an effective invention in reducing the size of the apparatus.

[Brief description of the drawings]

FIG. 1 is a perspective view showing the appearance of a copying apparatus using the present invention.

FIG. 2 is a schematic diagram showing the structure of the copying apparatus shown in FIG.

FIG. 3 is a schematic sectional view showing the internal configuration of the copying apparatus shown in FIGS.

FIG. 4A is a cross-sectional view illustrating a detailed structure of a sheet feeding unit of the copying apparatus illustrated in FIG. 3; (B) Explanatory drawing which showed the shape of the inner side guide surface in detail.

5 is a perspective view of an inner guide surface formed on a base of the copying apparatus shown in FIG. 3 as viewed from a left side of the apparatus.

FIG. 6A is an explanatory diagram illustrating a position where a sheet member is provided on an inner guide surface. (B) Explanatory drawing for showing the shape of a sheet member.

FIG. 7 is a timing chart related to paper feed control of the copying apparatus of FIG. 3;

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Shinji Yamamoto 1-2-28 Tamazuki, Chuo-ku, Osaka-shi, Osaka Inside Kyocera Mita Co., Ltd. 28 Kyocera Mita Co., Ltd. (72) Inventor Ryoji Kanematsu 1-2-2 Tamatsuzo, Chuo-ku, Osaka-shi, Osaka F-term in Kyocera Mita Co., Ltd. 2H072 CB09 JA04 3F048 AA02 AA04 AA05 AB01 BA05 CC01 DA06 DC05 3F101 FA01 FA02 FB01 FB02 FC01 FC05 FD02 LA02 LA05 LA07 LB03

Claims (6)

[Claims] A recording unit for recording on paper, a paper storage tray disposed below the recording unit for storing paper, and a paper feeding unit for feeding paper from the paper storage tray. ,
A sheet transport path for guiding the sheet fed from the sheet storage tray to the recording unit; and a sheet fed by the sheet feeding unit to the recording unit downstream of the sheet feeding unit in the sheet feeding direction. Transport means, and paper guide means formed between the paper feed means and the transport means and formed on the paper transport path, wherein the paper guide means has a guide surface for contacting the paper, An image forming apparatus, wherein a resin sheet member is provided on a guide surface. 2. The resin sheet member according to claim 1, wherein a sheet member made of polyethylene and having a thickness of 0.1 to 0.3 mm is attached to the guide surface with an adhesive.
Image forming apparatus. 3. An opening is formed in a part of said guide surface, and a detection switch for detecting that a conveyed sheet passes over said opening is provided. Item 1. The image forming apparatus according to Item 1. 4. The conveyance means is a registration roller, the paper feeding means is a half-moon roller, the paper conveyance path is curved between the registration roller and the half-moon roller, and the detection switch is the half-moon roller. 4. The image forming apparatus according to claim 3, wherein the presence / absence of paper supply from a roller and the detection of registration timing are also performed. 5. The image forming apparatus according to claim 1, wherein said sheet storage tray is supported by a structural member formed of a resin material, and said guide surface is formed integrally with said structural member. apparatus. 6. The guide surface is formed at a substantially central portion in the width direction of the paper conveyance direction, and a portion of the curved portion that is upstream of the curved portion in the paper conveyance direction is formed to have a more convex shape than both side portions thereof. The image forming apparatus according to claim 5, wherein the opening is provided in the protrusion, and the sheet member is provided around the opening in the protrusion.