JP2000001234A - Automatic document transport device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To regulate the number of documents to be small without creasing in a document by setting a projection amount of a roller part from the outer peripheral surface to the tip and a clearance gap between the outer peripheral edge of each roller part and a separating part. SOLUTION: Plural projecting separating parts 661 positioned corresponding to the space between the roller parts of a paper feed roller are formed on the lower end of a front separating plate 66. The front separating plate 66 is formed trapezoidal, and disposed with the tip projected inward from the outer peripheral surface 461 of the roller 46 parts of the paper feed roller. The projection amount (overlap) H1 from the outer peripheral surface 461 of each roller 46 parts of the paper feed roller to the tip of the handling part 661 is set to 0.1-0.4 mm, and a clearance H2 from the tip of the separating part 661 to the base of each roller 46 part, that is, the outer peripheral surface 441 of a cylindrical part 44 is set to 0.5-1.0 mm. Further, a clearance H3 of at least 0.2 mm is provided between the outer peripheral edge 462 of each roller 46 part and the separating part 661.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an automatic document feeder provided in a document processing machine such as an electrostatic copying machine, a facsimile or an image reader.

[0002]

2. Description of the Related Art In recent years, copiers have come to use an automatic document feeder which automatically and automatically supplies a plurality of documents to a document set position on the upper surface of a transparent plate with the speeding up and automation of copying processing. I have. An automatic document feeder for automatically feeding a plurality of documents sequentially to a document processor such as a facsimile or an image reader has been widely and practically used. An automatic document feeder of this type includes a document table on which a document is placed, a guide plate disposed downstream of the document table, and an opening formed in the guide plate disposed below the guide plate. A part of the outer peripheral portion projects upward and acts on the lower surface of the lowermost document placed on the document table to feed the document, and is disposed downstream of the forward roller in the transport direction. The image forming apparatus includes a paper feed roller, and a document separating mechanism disposed to face the paper feed roller. Further, a front separating means for regulating the number of originals entering between the paper feed roller and the original separating mechanism to a small number (1 to 3) is provided between the advance roller and the paper supply roller. ing.

The paper feed roller has a plurality of roller portions provided at a predetermined interval in the axial direction, and the pre-separating means is disposed so as to face in parallel with the axial direction of the feed roller. It has a front separating plate. The front separating plate has a convex separating portion positioned between the respective roller portions of the forward feed roller, and the tip of the convex separating portion is inward from the outer peripheral surface of each roller portion of the forward feed roller. It is arranged to protrude. A plurality of originals sent out by the forward feed roller are arranged so that a small number (1 to 3) of the originals pass through gaps between the convex separating portion and each roller portion of the paper feed roller. Transported to the side.

[0004]

In the automatic document feeder described above, the document is elastically deformed in a wavy manner when passing through the gap between the convex separating portion of the front separating plate and each roller portion of the forward feed roller. . However, in order to reduce the size of the automatic document feeder, if the separating means and the document separating mechanism are arranged adjacent to each other with the sheet feeding roller at the center, each of the convex separating section and the sheet feeding roller as described above is provided. When the document passes through the gap between the roller portions, the document is elastically deformed in a wave-like manner, and the wave-like deformation does not become small until the document reaches the document separating mechanism. Therefore, the original is pressed by the paper feed roller and the original separating mechanism in a state where the wavy deformation is not reduced, which causes wrinkles. In particular, this tendency becomes remarkable when the document separating mechanism is composed of separating rollers.

As described above, in order to reduce the wavy deformation generated when passing through the gap between the convex separating portion of the front separating plate and each roller portion of the sheet feeding roller, the convex separating portion is required. The configuration may be such that the section does not protrude from the outer peripheral surface of each roller section of the sheet feeding roller. However, if the separation unit does not protrude from the outer peripheral surface of each roller unit of the paper feed roller, it is not possible to regulate a large number of documents sent out by the forward feed roller to a small number of sheets, which may cause a conveyance failure. .

In the automatic document feeder described above, since the leading end of the separating portion of the front separating means rubs the surface of the original, the toner forming the original image may be scraped off. The toner that has been scraped off from the paper and adhered to the separation unit causes stains on a document to be fed subsequently.

[0007] The present invention has been made based on the above fact, and a first technical problem is to restrict a large number of originals fed by a forward feed roller to a small number of originals without causing wrinkles on the originals. It is an object of the present invention to provide an automatic document feeder provided with a pre-separating means capable of performing the following.

A second technical object of the present invention is to provide an automatic document feeder which can prevent the document from being stained by the front separating means.

[0009]

According to the present invention, there is provided a document table on which a document is placed, and a guide plate disposed downstream of the document table. A part of the outer peripheral portion is disposed below the guide plate, and a part of the outer peripheral portion protrudes upward from an opening formed in the guide plate, and acts on the lower surface of the lowest document placed on the document table to copy the document. A feed roller having a plurality of roller portions disposed at a predetermined interval in the axial direction and disposed at a downstream side in the transport direction of the forward feed roller; An automatic document feeder, comprising: a document separating mechanism disposed at a predetermined position; and a pre-separating means disposed opposite to the paper feed roller upstream of the document separating mechanism in the conveying direction. The means is disposed in the axial direction of the paper feed roller and each roller of the paper feed roller is provided. And a front separating plate having a convex separating portion positioned between the roller portions. The separating portion of the front separating plate has a leading end protruding inward from an outer peripheral surface of the roller portion of the sheet feeding roller. The protrusion amount from the outer peripheral surface of the roller portion to the tip is set to 0.1 to 0.4 mm, and the clearance from the tip of the separating portion to the bottom surface of each roller portion is set to 0.1 mm.
An automatic document feeder is provided which is set to 5 to 1.0 mm.

Further, according to the present invention, the separating portion of the front separating plate has a tip protruding inward from an outer peripheral surface of a roller portion of the sheet feeding roller, and is provided with an outer peripheral portion of the roller portion. The protrusion amount from the surface to the front end is set to 0.1 to 0.4 mm, and a gap of at least 2.0 mm is provided between the outer peripheral edge of each roller portion and the separating portion. Is provided.

[0011] In order to achieve the second technical problem,
According to the present invention, a document table on which a document is placed, a guide plate disposed on the downstream side of the document table, and an outer peripheral portion extending from an opening formed on the guide plate and disposed below the guide plate. A part of the portion protrudes upward and acts on the lower surface of the lowermost document placed on the document table to feed the document, and a forward feed roller disposed downstream of the forward feed roller in the transport direction and arranged in the axial direction. A paper feed roller having a plurality of roller portions provided at predetermined intervals, a document separation mechanism disposed opposite to the paper feed roller, and a paper feed mechanism upstream of the document separation mechanism in the transport direction. An automatic document feeder comprising: a front separation device disposed opposite to a paper feed roller; wherein the front separation device is disposed in an axial direction of the paper supply roller, and each roller portion of the paper supply roller is provided. A front separation plate having a convex separation portion positioned between the front separation plate and the front separation plate. The separating portion of the slab is disposed such that the tip protrudes inward from the outer peripheral surface of the roller portion of the paper feed roller, and the bottom surface of each roller portion of the paper feed roller has An automatic document feeder, wherein a toner removing member reaching the outer peripheral surface is mounted. Other features of the present invention will become apparent from the following description.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Preferred embodiments of an automatic document feeder constructed according to the present invention will be described below in detail with reference to the accompanying drawings.

FIGS. 1 and 2 show an upper end portion of the electrostatic copying machine 2 and an automatic document feeder 4 mounted thereon. The electrostatic copying machine 2 has a housing 6, and on the upper surface of the housing 6, a transparent plate 8 (FIG. 2), which may be a glass plate, is provided. On one side (left side in FIG. 2) of the transparent plate 8, a document regulating member 1 for defining a document set reference position G is provided.
0 is disposed, and a stationary mounting member 12 is disposed on the other side (the right side in FIG. 2). The automatic document feeder 4 configured in accordance with the present invention includes a housing 6 of the electrostatic copying machine 2.
1 is pivotally mounted between a closed position indicated by a solid line in FIG. 1 and an open position indicated by a two-dot chain line around a pivot axis extending along the rear edge of the transparent plate 8. Electrostatic copier 2
When the original is manually placed on the transparent plate 8, the automatic document feeder 4 is opened to expose the transparent plate 8, the original is placed at a required position on the transparent plate 8, and With the document feeder 4 closed, the transparent plate 8 and the document placed thereon are covered. When placing a document on the transparent plate 8, the document is required by placing one edge of the document against the leading edge of the document regulating member 10 and positioning the trailing edge of the document at the document setting reference position G. Position. When the document is automatically loaded onto the transparent plate 8 using the automatic document feeder 4 and is automatically output from the transparent plate 8, the automatic document feeder 4 is positioned at the closed position.

Continuing the description with reference to FIG. 1, the illustrated automatic document feeder 4 includes a front cover 14 and a rear cover which are spaced from each other in a front-rear direction (a direction perpendicular to the plane of FIG. 2). 16 is included. The front cover 14 and the rear cover 16 can be formed from an appropriate synthetic resin. A rear support substrate (not shown) is provided in the rear cover 16, and such a rear support substrate is connected via a mounting mechanism (not shown) which may itself be a known form. Thus, it is mounted on the upper surface of the housing 6 of the electrostatic copying machine 2 so as to be pivotable. Various components of the automatic document feeder 4 are directly or indirectly supported by the rear support substrate. A document placing means 18 and a document discharge tray 20 are provided between the front cover 14 and the rear cover 16. The original placing means 18 includes an original table 22 extending upward from the left end to the right rear end in FIG. 2 and an auxiliary table rotatably mounted at the rear end of the original table 22. 24. The document table 22 has a pair of width regulating members 26 movably in the width direction. The pair of width regulating members 26 are connected to each other below the document table 22 via a well-known rack and pinion mechanism (not shown), and approach each other in conjunction with each other. In the direction and away from each other.
The document discharge tray 20 is disposed below the document placing means 18 and has a document placing surface 201 formed in a mountain shape when viewed from the front-back direction (the direction perpendicular to the paper surface in FIG. 2). A left end cover 28 is disposed between the left ends of the front cover 14 and the rear cover 16, and a right end cover 29 is disposed between the right ends.

Continuing the description with reference to FIGS. 1 and 2, a forward feed means 30 is provided downstream of the document table 22 in the transport direction. The advance means 30 is
A guide plate 32 is provided extending downstream of the document table 22 in the transport direction. An opening is formed on the upstream side of the guide plate 32, and a forward feed roller 34 constituting the forward feed means 30 is disposed below the opening. The forward feed roller 34 is formed of an elastic material having a large friction coefficient such as urethane rubber, and is disposed so that a part of the outer peripheral surface slightly projects upward from an opening formed in the guide plate 32. The rotation axis (not shown) of the forward feed roller 34 is
It is operatively connected to an electric motor 35 as a drive source via a power transmission mechanism (not shown).

Above the forward feed roller 34, a forward feed pressure mechanism 36 constituting the forward feed means 30 is disposed. The forward feed pressurizing mechanism 36 includes a rotating shaft 36 disposed above the forward feed roller 34 in parallel with the forward feed roller 34.
2, and a pressing plate 364 which has an upper end fixed to the rotating shaft 362 and a lower end placed on the original table 22 and acting on the original (P) inserted on the guide plate 32. . The pressing plate 364 is formed of an elastic thin plate made of a stainless steel plate in the illustrated embodiment, and the upper end thereof is fixed to the rotating shaft 362 by a fixing means such as a screw. Feed roller 34
At the upper position of the uppermost document placed on the document table 22, it is positioned at an operating position for pressing the original and pressing the original, and a non-operating position separated from the original. The rotating shaft 362 constituting the forward feed pressing mechanism 36 is provided with side plates 39, 39 provided at front and rear ends of a support substrate 38 disposed above the forward feed roller 34.
(Only the rear side plate 39 is shown in FIG. 2). The turning shaft 362 is connected to a solenoid (not shown) via a link mechanism, and is turned in a predetermined direction when the solenoid is urged.
When the solenoid is de-energized, it is rotated in the direction opposite to the predetermined direction. Therefore, the pressing plate 364 attached to the rotating shaft 362 is biased by a solenoid (not shown) so that the rotating shaft 3
When the document 62 is rotated in a predetermined direction, it presses the document inserted above the guide plate 32, the solenoid is deenergized, and the rotating shaft 3 is rotated.
When 62 is rotated in the direction opposite to the predetermined direction, it is separated from the document.

A paper feed roller 40 is provided downstream of the advance unit 30. The paper feed roller 40 is provided as shown in FIG.
And a plurality of (four in the illustrated embodiment) roller portions 4 mounted on the outer peripheral surface of the rotating shaft 42 and the cylindrical portion 44 attached to the rotating shaft 42 as shown in FIG.
It consists of six. The rotating shaft 42 is operatively connected to an electric motor 35 as a driving source via a power transmission mechanism (not shown). The cylindrical portion 44 is formed in a cylindrical shape with an appropriate synthetic resin, and is integrally attached to the rotating shaft 42. The plurality of rollers 46 are formed of a material having a large coefficient of friction such as urethane rubber, and are mounted on the outer peripheral surface 441 of the cylindrical portion 44 at predetermined intervals in the axial direction. The plurality of rollers 46 are disposed such that a part of the outer peripheral surface slightly protrudes upward from an opening formed in the guide plate 32.

An original separating mechanism 50 is provided above the paper feed roller 40. The document separation mechanism 50 includes a separation roller 51 in the illustrated embodiment. The separation roller 52 includes a fixed shaft 52 and a cylindrical portion 53 formed of an appropriate synthetic resin and rotatably disposed on the fixed shaft 52.
And a surface layer portion 54 formed of an elastic material having a large coefficient of friction such as urethane rubber and attached to the outer peripheral surface of the cylindrical portion 53.
And a torque limiter mechanism 55 disposed between the fixed shaft 52 and the cylindrical portion 53, and the surface layer portion 54 is disposed in contact with the outer peripheral surface of the roller portion 46 of the paper feed roller 40. ing. The torque limiter mechanism 55 includes a cylindrical portion 53.
And a spring clutch mechanism for fixing the tubular portion 53 to the fixed shaft 52 when a predetermined or more driving torque acts on the fixed shaft 52.
The separation roller 51 having the torque limiter mechanism 55
It does not constitute a new feature in the automatic document feeder constituted by the present invention, and the constitution itself may be a known form, and therefore, for details of the constitution,
The description is omitted in this specification. In the illustrated embodiment, the separation roller 52 is used as the document separation mechanism 50.
However, as the document separation mechanism 50, a separation belt mechanism or another separation mechanism can be used.

On the upstream side of the document separation mechanism 50 in the direction of conveyance, a front separation means 60 is disposed so as to face the paper feed roller 40. The pre-separation means 60 includes a front segregation support plate 64 disposed in the axial direction of the paper feed roller 40 and having an upper end attached to the support substrate 38 by a screw 52, and an upper end formed at a lower end of the front segregation support plate 64. The front handling plate 66 is mounted. The front separating plate 66 will be described with reference to FIGS. The pre-separation plate 66 is formed by a sheet member having elasticity. In the illustrated embodiment, the pre-separating plate 66 is formed of a polyethylene terephthalate (PET) resin sheet member having a thickness of 0.125 mm, and its upper end is pre-separated by a fixing member such as an adhesive or a double-sided adhesive tape. It is mounted on a support plate 66. At the lower end of the front separating plate 66, a plurality of convex separating portions 661 provided at positions corresponding to between the respective rollers 46 of the paper feed roller 40 are formed. In the embodiment shown in FIGS. 3 and 4, the pre-separation plate 66 is formed in a trapezoidal shape, and its tip is disposed so as to protrude inward from the outer peripheral surface 461 of the roller 46 of the paper feed roller 40. I have.

Next, the dimensional relationship between the separation portion 661 of the front separation plate 66 and each portion of the sheet feeding roller 40 will be described. In the illustrated embodiment, the paper feed roller 40 is
6 is 7 mm, and the height (S2) from the bottom surface of each roller portion 46, that is, the outer peripheral surface 441 of the cylindrical portion 44 to the outer peripheral surface 461 of the roller portion 46 is 0.6 to 1.4 mm. Is set. The width (L1) of the base of the separating portion 661 is 6
mm, the width of the tip (L2) is set to 4 mm, and the height and width (L3) are set to 0.8 mm. In the illustrated embodiment, the outer peripheral surface 4 of each roller 46 of the paper feed roller 40 is used.
The amount of protrusion (overlap amount) (H1) from 61 to the leading end of the separating portion 661 is set to 0.1 to 0.4 mm, and the bottom surface of each roller 46, that is, the outer periphery of the cylindrical portion 44 from the leading end of the separating portion 661. The gap (H2) to the surface 441 is 0.5 to
It is set to 1.0 mm. In the illustrated embodiment, the outer peripheral edge 462 of each roller 46 and the separating portion 661 are provided.
Is provided with a gap (H3) of at least 2.0 mm.

Continuing the description with reference to FIG. 2, a transport belt mechanism 70 is provided below the original placing means 18. The transport belt mechanism 70 includes a drive roller 71 and a driven roller 72 disposed at intervals in the transport direction (the horizontal direction in FIG. 2), an endless belt 73 wound around these, a drive roller 71 and a driven roller 72. And a plurality of pressing rollers 74 disposed between the pressing rollers 74. The lower running portion of the endless belt 73 extends along the transparent plate 8 of the electrostatic copying machine 2, and a document conveying path 75 is defined between the two.

The original transport path 75 and the paper feed roller 40
A document carrying path 80 is formed between the two. This document carrying path 80 is defined by an inner guide plate 801 and an outer guide plate 802. A registration roller pair 82 is provided in the document carrying path 80. The registration roller pair 82 includes a driving roller 821 and a driven roller 822. The driving roller 8 of the registration roller pair 82
21 and the drive roller 71 of the conveyor belt mechanism 70
Is transmission-connected to an electric motor (not shown) via an appropriate power transmission mechanism.

A document discharging means 90 is provided on the right side of the document conveying path 75 in FIG. The original discharging means 90
Includes a document discharge path 92, a pair of conveying rollers 94 disposed in the document discharge path 92, and a discharge roller pair 96 disposed at a discharge side end of the document discharge path 92. The transport roller pair 94 includes a drive roller 941 and a driven roller 942, and the discharge roller pair 96 also includes a drive roller 961 and a driven roller 962. Driving roller 941 of conveying roller pair 94 and driving roller 9 of discharging roller pair 96
Numeral 61 is drivingly connected to an electric motor (not shown) via an appropriate power transmission mechanism.

The automatic document feeder in the illustrated embodiment is configured as described above, and its operation and effect will be described below. In performing the copying operation, the operator first places the document P to be copied on the document table 22 and inserts the document P forward and inserts the front end of the document P into the forward feed roller 32.
On the upper side of. Then, when the copy start key is pressed by the operator, the solenoid (not shown) of the forward feed pressing mechanism 36 is urged, the pressing plate 364 is positioned at the operation position, and the document P inserted on the guide plate 32 is pressed. I do. The electric motor 35 is driven simultaneously with the pressing of the document P by the pressure plate 364, and the forward feed roller 34 and the paper feed roller 40 are driven to rotate in the direction indicated by the arrow in FIG. The rotation of the forward feed roller 34 in the direction indicated by the arrow in FIG. 2 causes the contact between the outer peripheral surface of the forward feed roller 34 and the lower surface of the lowermost document in the document layer inserted on the guide plate 32. The original is sent out by the frictional conveying force. At this time, the originals on the original layer are moved in the transport direction due to friction between each other, but a small number (1 to 3) of the originals are transported downstream by being regulated by the front separating means 60.

Next, the operation of the pre-separating means 60 will be described. As shown in FIG. 4, the plurality of originals sent out by the advance feed roller 34 are regulated by the front separation plate 66 of the front separation means 60, and a small number (1 to 3) of the originals are fed to the convex separation portion 661. The paper is passed between the rollers 46 of the paper roller 40 and conveyed to the document separation mechanism 50 side. In addition,
Since the pre-separation plate 66 is formed of an elastic sheet member, it is elastically deformed in the transport direction when the original is separated, so that the passage of the original is improved. At this time, the amount of protrusion (overlap amount) from the outer peripheral surface 461 of the roller 46 of the paper feed roller 40 to the tip of the separating portion 661 (H
If 1) is less than or equal to zero, the pre-separation effect of the document is small, and many documents are conveyed to the document separation mechanism 50 side. On the other hand, if the protrusion amount (overlap amount) (H1) is large, the pre-separating action of the document is improved, but the wave-like shape generated when the document passes between the separating section 661 and each of the rollers 46 of the paper feed roller 40 is increased. The amount of elastic deformation of the paper feed roller 32
And the separation roller 51 of the document separation mechanism 50 pressurizes the paper to generate wrinkles. According to the experiments by the present inventors, when the protrusion amount (overlap amount) (H1) is 0.1 mm or more, the document can be separated into a small number (1 to 3). On the other hand, if the protrusion amount (overlap amount) (H1) is 0.4 mm or less, if the amount of wavy elastic deformation generated when the document passes through the separating portion 661 and each of the rollers 46 of the feed roller 40 is large, Paper feed roller 32 and document separation mechanism 50
No wrinkles occurred when passing through the separation roller 51. Therefore, the protrusion amount (overlap amount) (H1) is equal to 0.
It is desirable to set it to 1 to 0.4 mm. Also, the gap (H2) from the leading end of the separating portion 661 to the bottom surface of the roller portion 46, that is, the outer peripheral surface 441 of the cylindrical portion 44, is a wavy elasticity generated when the document passes between the separating portion 661 and the roller portion 46. The amount of deformation is affected. According to experiments by the present inventors, if the gap (H2) is smaller than 0.5 mm, the gap may not be able to pass through depending on the paper quality of the document. On the other hand, if the gap (H2) is larger than 1.0 mm, the amount of wavy elastic deformation generated when the document passes between the separating portion 661 and each of the rollers 46 of the paper feed roller 40 increases. Therefore, the gap (H2) is 0.5 to 1.
It is desirable to set it to 0 mm. Further, the paper feed roller 4
The gap (H3) between the outer peripheral edge 462 of each roller 46 and the separation portion 661 also affects the document separation effect. According to the experiments performed by the present inventors, if the gap (H3) is smaller than 2.0 mm, the passage property is poor depending on the paper quality of the document.
It is desirable that the gap (H3) be set to 2.0 mm.

As described above, the document which is regulated to a small number (1 to 3 sheets) by the action of the pre-separating means 60
When the document 2 passes through the separation roller 51 of the document separation mechanism 50, only the lowermost document is separated and conveyed to the document carrying path 80. Then, the front end of the document conveyed to the document carrying path 80 is brought into contact with the nip portion of the registration roller pair 82 in a non-operating state, and the primary sheet feeding is completed.

When the primary paper feeding is completed as described above,
The registration roller pair 82 and the transport belt mechanism 70 are operated to position the trailing edge of the primary fed document at the document setting reference position G on the transparent plate 8. Then, an exposure operation is performed. When the exposure operation is completed, the transport belt mechanism 7
The pair of transport rollers 94 and the pair of discharge rollers 96 of the document discharge means 90 and the discharge roller 96 are operated, and the document which has been exposed on the transparent plate 8 is passed through the document discharge path 92 to the document discharge tray
The document is discharged onto the original placing surface 201 of the “0” document.

Next, another embodiment of the separation portion of the front separation plate 66 constituting the front separation means 60 will be described with reference to FIG. The same members as those of the embodiment shown in FIGS. 3 and 4 are denoted by the same reference numerals, and description thereof will be omitted.
The separation portion 662 of the front separation plate 66 shown in FIG. 5 is formed in an arc shape. By forming the separating portion 662 in an arc shape in this manner, the document can be separated from the separating portion 662 and the sheet feeding roller 40.
Can be made smaller than the trapezoidal shape having the same size when passing between the rollers 46.

Next, another embodiment of the paper feed roller 40 will be described with reference to FIG. The same members as those in the embodiment shown in FIG. 3 and FIG.
The description is omitted. In the paper feed roller 40 shown in FIG. 5, a toner removing member 48 is mounted on the bottom surface of each roller portion 46, that is, on the outer peripheral surface 441 of the cylindrical portion 44. This toner removing member 48 is a rubber sheet material 48 in the illustrated embodiment.
The lower surface of the sheet member 481 is attached to the bottom surface of each roller portion 46, that is, the outer peripheral surface 441 of the cylindrical portion 44 by a fixing member such as an adhesive or a double-sided adhesive tape. Have been. The bristle material 482 of the toner removing member 48 having such a configuration is formed such that the tip thereof substantially matches the outer peripheral surface of each roller portion 46. On the other hand, a plurality of convex separating portions 661 formed on the front separating plate 66 of the front separating means 60 have their leading ends spaced from the outer peripheral surface 461 of each roller 46 of the sheet feeding roller 40 by 0.1 to 0.2 mm.
It is configured to protrude 4 mm. Therefore, the separating section 661
Is inserted into the toner removing member 48.

Since the feed roller 40 and the front separating plate 66 shown in FIG. 5 are configured as described above, the following operation and effect can be obtained. That is, the separation portion 661 of the front separation plate 66
May scrape off the toner forming the document image, and the toner scraped off from the document adheres to the separating portion 661. This separating part 6
The toner adhering to 61 is wiped off by the toner removing member 48 when the document passes through the front separating plate 66.
Therefore, the document fed thereafter will not be stained. Also,
The toner removing member 48 also has an effect of reducing the amount of wavy elastic deformation generated when the document passes between the separating portion 662 and each of the rollers 46 of the paper feed roller 40.

[0031]

The automatic document feeder according to the present invention is constructed as described above, and has the following effects.

That is, since the relationship between the separation portion of the front separation plate and each roller portion of the paper feed roller is set as described above,
The amount of wavy elastic deformation generated when the document passes through the separation section and each roller section of the paper feed roller can be suppressed to a small value. Accordingly, the amount of the wavy elastic deformation is considerably small before reaching the document separating mechanism, and therefore, it does not wrinkle even when pressed by the paper feed roller and the document separating mechanism.

According to the present invention, since the toner removing member is mounted on the bottom surface of each roller portion of the paper feed roller,
The separating portion of the front separating plate scrapes off the toner forming the original image when separating the original, and even if this toner adheres to the separating portion, the toner is removed by the toner removing member when the original passes through the front separating plate. Wiped off. Therefore, the document fed thereafter will not be stained.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a state in which a preferred embodiment of an automatic document feeder configured according to the present invention is mounted on an electrostatic copying machine.

FIG. 2 is a schematic sectional view of the automatic document feeder shown in FIG.

FIG. 3 is a front view showing an embodiment of a paper feed roller and a front separation plate provided in the automatic document feeder shown in FIGS. 1 and 2;

FIG. 4 is an enlarged view of a main part showing a state in which a document passes between a paper feed roller and a front separating plate shown in FIG. 3;

FIG. 5 is a front view showing another embodiment of a sheet feed roller and a front separation plate provided in the automatic document feeder shown in FIGS. 1 and 2;

FIG. 6 is an enlarged sectional view of a main part showing still another embodiment of a sheet feeding roller and a front separating plate provided in the automatic document feeder shown in FIGS. 1 and 2;

[Explanation of symbols]

 2: electrostatic copying machine 4: automatic document feeder 6: housing of electrostatic copying machine 8: transparent plate 18: document placing means 20: document discharge tray 22: document table 30: forward feed means 32: guide plate 34: Forward feed roller 35: Electric motor 36: Pressing mechanism 362: Rotating shaft of pressing mechanism 364: Pressing plate of pressing mechanism 38: Support substrate 40: Feed roller 42: Rotating shaft of feed roller 44: Feeding Roller tubular part 46: Paper feed roller part 50: Document separation mechanism 51: Separation roller 60: Front separation means 64: Front separation means support plate 66: Front separation plate 661: Front separation plate separation part 48: Toner removing member 70: transport belt mechanism 71: drive roller of transport belt mechanism 72: driven roller of transport belt mechanism 73: endless belt of transport belt mechanism 74: pressing roller of transport belt mechanism 75: document transport path 80: Document carry-in path 82: Registration roller pair 90: Document discharge means 92: Document carry-out path 94: Transport roller pair 96: Discharge roller pair

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Hiroyuki Harada 1-2-28 Tamazo, Chuo-ku, Osaka-shi Inside Mita Kogyo Co., Ltd. (72) Takachi Fukumoto 1-2-28 Tamazo, Chuo-ku, Osaka Mita Within the Industrial Co., Ltd. (72) Inventor Shigeo Kurato 1-2-2, Tamazo, Chuo-ku, Osaka Mita Kogyo Co., Ltd. F-term (reference) 3F343 FA03 FB02 FB03 FC04 GA01 GB02 GC01 GD01 KA03 KA11 KA18 KA20

Claims (14)

[Claims] 1. An original table on which an original is placed, a guide plate disposed downstream of the original table, and an outer peripheral portion disposed below the guide plate and formed through an opening formed in the guide plate. A forward feed roller for projecting the original by feeding a part of the lowermost original protruding upward and acting on the lower surface of the original placed on the original table;
A paper feed roller provided with a plurality of roller portions provided at a predetermined interval in the axial direction and disposed downstream of the forward feed roller in the transport direction, and provided facing the paper feed roller; An automatic document feeder comprising: a document separating mechanism; and a pre-separating means disposed opposite to the paper feed roller upstream of the document separating mechanism in a conveying direction. A front separating plate provided in the axial direction of the roller and having a convex separating portion positioned between the respective roller portions of the sheet feeding roller, the leading end of the separating portion of the front separating plate being the feed roller Are arranged to protrude inward from the outer peripheral surface of the roller portion, and the amount of protrusion from the outer peripheral surface of the roller portion to the tip is 0.1 to 0.1 mm.
An automatic document feeder, wherein the gap is set to 4 mm, and a gap from the leading end of the separating section to the bottom of each roller section is set to 0.5 to 1.0 mm. 2. The automatic document feeder according to claim 1, wherein said separation portion of said front separation plate is formed in a trapezoidal shape. 3. The automatic document feeder according to claim 1, wherein the separation portion of the front separation plate is formed in an arc shape. 4. The automatic document feeder according to claim 1, wherein said pre-separation plate is formed of an elastic sheet member. 5. An original table on which an original is placed, a guide plate disposed downstream of the original table, and an outer peripheral portion disposed below the guide plate and formed through an opening formed in the guide plate. A forward feed roller for projecting the original by feeding a part of the lowermost original protruding upward and acting on the lower surface of the original placed on the original table;
A paper feed roller provided with a plurality of roller portions provided at a predetermined interval in the axial direction and disposed downstream of the forward feed roller in the transport direction, and provided facing the paper feed roller; An automatic document feeder comprising: a document separating mechanism; and a pre-separating means disposed opposite to the paper feed roller upstream of the document separating mechanism in a conveying direction. A front separating plate provided in the axial direction of the roller and having a convex separating portion positioned between the respective roller portions of the sheet feeding roller, the leading end of the separating portion of the front separating plate being the feed roller Are arranged to protrude inward from the outer peripheral surface of the roller portion, and the amount of protrusion from the outer peripheral surface of the roller portion to the tip is 0.1 to 0.1 mm.
The automatic document feeder is set to 4 mm, and a gap of at least 2.0 mm is provided between the outer peripheral edge of each roller unit and the separation unit. 6. The automatic document feeder according to claim 5, wherein said separation portion of said front separation plate is formed in a trapezoidal shape. 7. The automatic document feeder according to claim 5, wherein said separating portion of said front separating plate is formed in an arc shape. 8. The automatic document feeder according to claim 5, wherein said pre-separation plate is formed of an elastic sheet member. 9. A document table on which a document is placed, a guide plate disposed downstream of the document table, and an outer peripheral portion extending from an opening formed below the guide plate and formed in the guide plate. A forward feed roller for projecting the original by feeding a part of the lowermost original protruding upward and acting on the lower surface of the original placed on the original table;
A paper feed roller provided with a plurality of roller portions provided at a predetermined interval in the axial direction and disposed downstream of the forward feed roller in the transport direction, and provided facing the paper feed roller; An automatic document feeder comprising: a document separating mechanism; and a pre-separating means disposed opposite to the paper feed roller upstream of the document separating mechanism in a conveying direction. A front separating plate provided in the axial direction of the roller and having a convex separating portion positioned between the respective roller portions of the sheet feeding roller, the leading end of the separating portion of the front separating plate being the feed roller Wherein the toner removing member is mounted on the bottom surface of each of the roller portions of the paper feed roller. 10. The automatic document feeder according to claim 9, wherein said toner removing member is constituted by a flocked member. 11. The separation portion of the front separation plate has a protrusion amount of 0.1 to 0.4 mm from the outer peripheral surface of the roller portion to the front end.
The automatic document feeder according to claim 9, wherein: 12. The automatic document feeder according to claim 9, wherein the separation portion of the front separation plate is formed in a trapezoidal shape. 13. The automatic document feeder according to claim 9, wherein said separation portion of said front separation plate is formed in an arc shape. 14. The automatic document feeder according to claim 9, wherein said pre-separation plate is formed of an elastic sheet member.