JP2002370860A - Sheet material feeder and image forming device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sheet feeder capable of preventing, completely at low cost, a document from being included when it is reversed. SOLUTION: This sheet feeder including a sheet loading deck on which a plurality of sheets can be loaded, a sheet feeding means which sequentially feeds the sheets loaded on the sheet loading deck one by one, and a controller which rotates in the reverse direction to the travel of the sheets has a driven rotating body 3e brought into pressure contact with a feeding roller (driving rotating body) 3d to be driven, a sheet inclusion preventing member 4 is vertically movably attached to both ends of the driven rotating body 3e, and a sheet back prevention surface 4a in roughly parallel with a surface connecting the axial center line of the feeding roller 3d with that of the driven rotating body 3e is provided on the sheet inclusion preventing member 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sheet feeding apparatus and an image forming apparatus having the same.

[0002]

2. Description of the Related Art Conventionally, to prevent the trailing edge of paper from being caught in reverse rotation,
As shown in FIG. 10, an arm 4x serving as a weight is attached, and the original is dropped by the weight.

[0003]

However, in the above-mentioned prior art, when the original is discharged, the weight must be increased in order to drop the original without fail. The paper discharge angle was changed, and the paper was inverted, dropped, etc. at the time of paper discharge. Also, if the weight is light, the trailing edge of the document remains, causing a roll-up.

SUMMARY OF THE INVENTION The present invention has been made in view of the above problems, and has as its object to provide a sheet feeding apparatus and an image forming apparatus capable of reliably preventing the original from being entangled at the time of reverse rotation at a low cost. It is in.

[0005]

SUMMARY OF THE INVENTION In order to achieve the above object, the present invention provides a sheet mounting table on which a plurality of sheets can be stacked, and one sheet mounted on the sheet mounting table. In a sheet material feeding apparatus having a sheet material feeding means for sequentially feeding and a control means for rotating in a direction opposite to the sheet material conveying direction, a driven rotating body which is pressed against a driving rotating body and is driven to rotate is provided. A sheet material entanglement prevention member is attached to both ends of the driven rotator so as to be vertically movable, and the sheet entanglement prevention surface is substantially parallel to a surface connecting the drive rotator and the axis of the driven rotator. Is provided.

Further, the present invention provides a sheet mounting table on which a plurality of sheet materials can be stacked, sheet material feeding means for sequentially feeding the sheet materials mounted on the sheet mounting table one by one, In a sheet material feeding device having a sheet material regulating means for regulating a front end of a sheet material placed on the sheet material mounting table, a rotating body is provided in the sheet material feeding means, and the rotating body includes the sheet. A mechanism for switching between regulation and release of the leading end of the sheet material by the material regulating means, wherein the sheet regulating means regulates the leading edge of the sheet material at the front end of the sheet material by the mechanism when the rotating body rotates in the sheet material conveying direction. It has a configuration that is returned to a position, has a driven rotator that is driven to rotate by being pressed against the driving rotator, and a sheet material entanglement prevention member is attached to both ends of the driven rotator so that the sheet material entanglement member is vertically movable. ,Previous Characterized in that a drive rotor and prevent regulating surface substantially back parallel sheet material to a surface connecting the axial center line of the driven rotating body.

Further, the present invention provides a sheet material to be read or a sheet material to be recorded in an image forming apparatus having at least one of reading means for reading an image and recording means for recording an image. The above-mentioned sheet material feeding device is provided as a sheet material feeding means for sequentially feeding the reading means or the recording means one by one.

[0008]

Embodiments of the present invention will be described below with reference to the accompanying drawings.

First Embodiment First, a schematic configuration of a facsimile apparatus will be described with reference to FIG.

In FIG. 8, reference numeral 1 denotes an apparatus main body. The apparatus main body 1 includes an image reading section 2 for reading an image of a document S as a reading target, and an image for recording an image on a recording paper P as a recording target. The recording unit 15 is configured.

The image reading section 2 includes an upper cover 8 having an original mounting table 8a on which a plurality of originals S can be mounted, and a contact type image sensor 3k for reading image information of the original S.
A document pressing portion 3j pressing the document S against the contact image sensor 3k; and a document S placed on the document placing table 8a, which is sequentially fed one by one through the contact image sensor 3k. The document transport unit 3 includes a document transport unit 3 for transporting the document S, and an upper document guide 5 and a lower document guide 7 that form a transport path for the document S.

An upper cover 8 having the document table 8a
Is attached to the apparatus main body 1 so as to be openable and closable so that a cartridge exchange and a jam clearance described later can be easily performed. Further, a slider 8b slidable in the width direction orthogonal to the direction of transport of the original S is provided on the original mounting table 8a, and the slider 8b is
Both ends of the original S placed on the upper side can be aligned.

The contact type image sensor 3k irradiates the image information surface of the document S with light from an LED array as a light source, and uses the Selfoc lens (registered trademark) to sense the reflected light reflected from the image information surface. The image information is read by forming an image on the element. The document feeder 2 as an automatic document feeder to which the present invention is applied will be described later.

The image recording section 15 includes a loading section 23 for loading a recording sheet P as a recording target, and a recording sheet loading section 23.
Paper feeding section 12 for sequentially feeding recording paper P one by one from
An image forming unit 11 for recording and forming an image on the fed recording paper P; a laser scanner 13 for irradiating the image forming unit 11 with laser light as image information; A common discharge tray 19 for loading and holding the recording paper P, a recording paper discharge table 18 for loading and holding the recording paper P discharged in a U-turn after recording, and a transport guide 17 for guiding and supporting the recording paper P to be transported. .

When the feeding is started, the separating / conveying section 12 transfers the recording paper P pressed against the separating roller 12b to the separating roller 12b and the separating pad 12a pressed against the separating roller 12b.
After the sheets are separated one by one, the leading edge of the image (toner image) formed by the image forming unit 11 by the transport roller 12c and the transport roller 12d which is pressed and rotated by the roller is coincident with the leading edge of the recording paper P. The photosensitive drum 11a of the image forming unit 11 and the transfer unit 1
1f.

The recording paper stacking section 23 has a plurality of recording papers P.
Can be loaded, and the number of sheets that can be set
It is about 00 sheets. Further, the size of the recording paper P that can be stacked and set is three types: A4 size, letter size, and legal size.

In the image forming section 11, first, a laser beam as an image signal is emitted from a laser beam oscillator of a laser scanner 13 based on the image signal. This laser light is transmitted to the polygon mirror 13b and the return mirror 1
Irradiation is performed on the photosensitive drum 11a of the image forming unit 11 by 3c, and an image is formed on the surface of the photosensitive drum 11a.

In the image forming section 11, the photosensitive drum 11a is incorporated in a frame together with a charging means 11b, a developing means 11c and a cleaning means 11d as process means acting thereon, and a process cartridge 11e.
Is detachably attached to the apparatus main body 1. Therefore, during the above-described image formation, a laser beam is irradiated from the laser scanner 13 on the surface of the photosensitive drum 11a uniformly charged by the charging unit 11b to form a latent image, and the latent image is supplied from the developing unit 11c. Thereby, a visualized image (toner image) is formed.

In the image forming section 11, a transfer means 1 for transferring a toner image formed on the surface of the photosensitive drum 11a to a recording paper P is provided around the photosensitive drum 11a.
1f, and a fixing unit 14 for fixing the transferred toner image to the recording paper P is disposed on a recording paper transport path downstream of the photosensitive drum 11a.
In the figure, reference numeral 15 denotes a discharge roller.

Therefore, the recording paper P fed from the recording paper stacking section 23 to the image forming section 11 at a proper timing is transferred after the toner image formed on the surface of the photosensitive drum 11a is transferred by the transfer means 11f. The toner image is conveyed along a conveyance guide 17, the toner image is fixed by the fixing unit 14, and is discharged to a common discharge tray 19 or a recording paper discharge table 18 by a discharge roller 15.
If a paper jam occurs during recording, the recording paper P staying inside the apparatus can be easily taken out by opening the open / close bar of the upper cover 8 having the document placing table 8a.

FIG. 1 is a perspective view of the document entanglement preventing member 4. In FIG.
Is a document conveying slope, 4e is a vertical positioning portion, 3e is a driven rotary member, and 3d is a paper discharge roller.

As shown in FIG. 2, the document return prevention regulating surface 4
a is substantially downstream of the nip portion and substantially parallel to a plane connecting the driven rotator 3e and the axial center line of the discharge roller 3d, and has a distance of 0 to 5;
It is effective to select within the range of mm. In the present embodiment, this distance is set to 1.5 mm. In addition, by providing the vertical positioning portion 4e, the vertical position of the document return prevention regulating surface 4a is determined. Further, the document is transported smoothly by providing the document transport / conveying slope 4b.

FIGS. 3 and 4 show the operation of the document entanglement preventing member 4 when the document is conveyed and discharged.

As shown in FIG. 3, when the document enters, it moves upward, and as shown in FIG. 4, it returns elastically downward after the document is discharged. In the present embodiment, the elasticity of the document entanglement preventing member 4 itself is used, but the same applies to the case where the pressing force is adjusted by a spring or the like. After the sheet is discharged, the document is prevented from being caught in the nip portion by the document return prevention regulating surface 4a.

FIG. 6 is a top view of the upper document table unit.
As shown in the figure, the document entanglement preventing members 4 are located at both ends of the driven rotary member 3e, and are attached to the upper document guide with screws. It goes without saying that this fixing method may be bonding or snap fitting.

Here, as shown in FIG.
e, the distance from both ends to the document entrainment preventing member 4 is 0 to
It shall be selected between 10 mm. This embodiment, 1.5
mm.

By the document entanglement preventing member 4, the document trailing end does not return to the nip after the document is discharged, so that the document can be completely shut out. Since the initialization of the document leading edge regulating mechanism is a known technique, the description is omitted here.

As shown in the automatic document feeder of FIG. 5, the image reading section 2 is stacked on the document storage table 8a. First, the original S is set. The original S is a preliminary press-welding arm 3h
And the separating roller 3a pressed against the stopper 3g, and collides with the stop surface of the stopper 3g, so that the stopper 3g cannot go further.

Next, when the conveyance of the original S is started, the stopper 3g is opened by the open moped feeding roller 3c,
Pre-pressing arm 3h and separation roller 3a pressed against it
As a result, the sheet is separated and fed one by one by the separation roller 3a pressed to the friction piece 3b while being fed to the friction piece 3b. In the case of single-sheet feeding, the sheet is fed by the pre-pressing arm 3h and the separation roller 3a pressed against it, and reaches the picture feeding roller 3d.

Further, the original S is conveyed to the contact image sensor 3k by the sheet supply roller 3d pressed against the sheet supply roller 3c pressed by the pressing spring 3i, and the document S is pressed against the contact image sensor 3k by the document pressing plate 3j. After reading the image information of the original S while line-feeding the original sequentially while bringing the originals into close contact with each other, the original S and the recording paper are shared by a discharge roller 3f pressed against the discharge opening 3e pressed by the pressing spring 3i. The paper is discharged to the paper discharge tray 18. During this time, the document S is guided by the upper document guide 5 and the lower document guide 7. After the document is discharged, the motor is rotated reversely to initialize the stopper 3g. At this time, the rear end of the document S is shut out by the document wrap preventing member 4.

[0031]

As is apparent from the above description, according to the present invention, a sheet mounting table on which a plurality of sheets can be stacked, and one sheet mounted on the sheet mounting table. In a sheet material feeding apparatus having a sheet material feeding means for sequentially feeding and a control means for rotating in a direction opposite to the sheet material conveying direction, a driven rotating body which is pressed against a driving rotating body and is driven to rotate is provided. A sheet material entanglement preventing member is attached to both ends of the driven rotator so as to be vertically movable, and the sheet entanglement prevention surface is substantially parallel to a surface connecting the drive rotator and the axis center line of the driven rotator. Is provided, an effect is obtained that the document can be reliably prevented from being entangled at the time of reverse rotation at low cost.

[Brief description of the drawings]

FIG. 1 is a perspective view of a document entanglement prevention mechanism according to the present invention.

FIG. 2 is a front sectional view of the document entanglement prevention mechanism according to the present invention.

FIG. 3 is a front sectional view of the document entanglement prevention mechanism according to the present invention when a document enters.

FIG. 4 is a front sectional view of the document entanglement prevention mechanism according to the present invention at the time of document ejection.

FIG. 5 is a front sectional view of the automatic sheet feeder according to the present invention.

FIG. 6 is a top view of the upper document table unit of the automatic sheet feeder according to the present invention.

7 is a view in the direction of arrow A in FIG. 6;

FIG. 8 is a front sectional view of a facsimile provided with the automatic sheet feeder according to the present invention.

FIG. 9 is a perspective view of a facsimile provided with the automatic sheet feeder according to the present invention.

FIG. 10 is a front sectional view of a conventional automatic sheet feeder.

[Explanation of symbols]

 3a Separation roller 3b Friction piece 3c Feeding roller with open source 3d Feeding roller 3e Follower rotator 3f Discharge roller 3g Stopper 3h Preliminary press-contact arm 3i Press spring 3j Document pressing plate 3k Close contact image sensor 4 Document wrap preventing member 4a Document Return prevention regulating surface 5 Upper document guide 7 Lower document guide 8 Top cover

 ──────────────────────────────────────────────────続 き Continued on the front page F term (reference) 2H076 BA17 BA20 BA24 BA35 BA36 BA47 BA63 3F101 FA01 FB12 FD02 FE02 LA02 LA07 LB03 3F343 FA03 FB03 FC03 GA02 GB01 GC01 GD01 HA14 KA03 KA13 LA04 LA15 LB05 5C062 AA32 AB06 AB31 AB31

Claims (8)

[Claims] A sheet material mounting table on which a plurality of sheet materials can be stacked; sheet material feeding means for sequentially feeding the sheet materials mounted on the sheet material mounting table one by one; and a sheet material conveying direction. In a sheet material feeding device having a control means that rotates in a direction opposite to the direction, a driven rotator that is driven to rotate by being pressed against the driving rotator is provided,
A sheet material entanglement prevention member is attached to both ends of the driven rotator so as to be movable up and down, and the sheet entanglement prevention member is provided with a sheet material return prevention rule substantially parallel to a plane connecting an axis of the driving rotator and the driven rotator. A sheet material feeding device having a surface. 2. A sheet material mounting table on which a plurality of sheet materials can be stacked, sheet material feeding means for sequentially feeding the sheet materials mounted on the sheet material mounting table one by one, and the sheet material mounting means In a sheet material feeding device having a sheet material regulating device for regulating a front end of a sheet material placed on a mounting table, a rotating body is provided in the sheet material feeding device, and the rotating body is provided by the sheet material regulating device. A mechanism for switching between regulation and release of the sheet material tip is provided, and the sheet regulating means includes:
When the rotator rotates in the sheet conveying direction, the mechanism is configured to return to an initial position where the leading end of the sheet material is regulated by the mechanism, and a driven rotator that is pressed against the driving rotator and is driven to rotate. A sheet material entanglement prevention member is vertically movably attached to both ends of the driven rotator, and the sheet entanglement prevention member is configured to prevent the sheet material from returning substantially parallel to a plane connecting the axis of the drive rotator and the axis of the driven rotator. A sheet material feeding device having a regulating surface. 3. The sheet material feeding device according to claim 1, wherein the sheet material entanglement preventing member is a resin-integrated molded product. 4. The sheet material feeding device according to claim 1, wherein the sheet material entanglement preventing member has a part of a circumferential surface that is substantially the same as a pressure contact surface of the driven rotating body. 5. The sheet material feeding device according to claim 1, wherein the sheet material entanglement preventing member is attached within 10 mm from both ends of the driven rotating body. 6. The sheet member return prevention regulating surface is disposed downstream of a nip portion between the driving rotator and the driven rotator and within 5 mm from a plane connecting the axial center lines of the two rotators. The sheet material feeding device according to claim 1, wherein: 7. The sheet material feeding device according to claim 1, wherein the sheet material entanglement preventing member has a slope within 45 ° with respect to the sheet material conveyance direction. 8. An image forming apparatus having at least one of a reading unit for reading an image and a recording unit for recording an image, wherein the reading unit reads a sheet material to be read or a sheet material to be recorded. 3. An image forming apparatus comprising the sheet material feeding device according to claim 1 or 2 as a sheet material feeding device for sequentially feeding the recording material one by one.