JP2003081475A - Document feeder - Google Patents

Abstract

PROBLEM TO BE SOLVED: To give the least possible skew to documents when carried by preventing a side guide from being out of restriction by the gradual rise of the documents at both sides when delivered out of a feed tray. SOLUTION: The document feeder comprises the feed tray 2 for stacking the document, the side guide 12 to be slid on the feed tray 2 in the cross direction of the documents for restricting the side positions of the documents, a delivery roller 6 for contacting and delivering the documents placed on the feed tray 2, and a feed roller 7 located on the downstream side of the delivery roller 6 for feeding the delivered documents to a carrier path 20. The side guide 12 is provided extending to the downstream side of a delivery position where the delivery roller 6 contacts the documents, and an upper face restricting guide 14 is arranged near the delivery position for restricting the positions of the upper faces of the documents when delivered.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electrophotographic copying machine,
The present invention relates to a document feeding device for feeding a document to a document reading position in a document reading device such as a facsimile and a printer.

[0002]

2. Description of the Related Art Generally, in a document reading device such as an electrophotographic copying machine or a facsimile, a plurality of documents are fed out one by one and automatically fed to a document reading position.
A document feeder called a so-called ADF (Automatic Document Feeder) is used. This type of document feeder is provided with a document feeder for automatically feeding and feeding the documents stacked on the paper feed tray one by one.

Conventionally, this type of document feeder has a sheet feed tray on which documents are stacked, a pickup roller arranged at the front end of the sheet feed tray to feed the documents in contact with the uppermost surface of the stacked documents, and this pickup. It is provided with a paper feed roller and a separation pad which are located on the downstream side of the roller to feed the originals one by one into the conveyance path while separating them one by one. The paper feed tray is provided with side guides that slide in the width direction of the document, and the skew of the document is prevented by restricting both side surfaces of the fed document.

The technique disclosed in Japanese Utility Model Publication No. 6-2982 is intended to further prevent the skew of a document, and has a structure in which the leading end side of the side guide is extended to the vicinity of the pickup roller. With such a configuration, both sides of the document fed out by the pickup roller are regulated to the vicinity of the paper feed port, and the straightness of the document guided to the paper feed roller becomes more reliable.

[0005]

However, even when the side guides are extended to the vicinity of the pickup roller as in the above-mentioned conventional method, both side portions of the original document have a curl tendency or both side portions of the original document float up when the original is picked up by the pickup roller. In such a case, as the document is fed out, both sides of the document gradually rise up and come off the guide surface of the side guide, which also causes the document skew to gradually increase.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide an original document feeding device for suppressing the skew of the original document as much as possible by preventing both side portions of the original document from gradually rising and falling out of the regulation of the side guide when the original document is fed out. To provide.

[0007]

In order to solve the above-mentioned problems, a document feeder according to claim 1 of the present invention comprises a sheet feed tray on which documents are stacked and a document width direction on the sheet feed tray. A side guide that slides to regulate the side position of the document, a feeding unit that feeds the document in contact with the document placed on the paper feed tray, and a feeding unit located downstream of the feeding unit. In a document feeding device including a document feeding unit that feeds a document to a conveyance path, the side guide is extended downstream of a feeding position where the feeding unit comes into contact with the document, and the document is provided near the feeding position. It is characterized in that an upper surface regulation guide for arranging the upper surface position of the document at the time of feeding is arranged.

It is desirable that the above-mentioned upper surface regulating guide is provided on the side surface of the side guide in the vicinity of the feeding position. In particular, by integrally molding, the side guide regulating effect of the side surface portion and the upper surface regulating guide effect of the upper surface combine to effectively prevent the skew of the document.

Further, it is desirable that the above-mentioned document surface pressure contact guide is arranged at a substantially central portion of the paper feed tray in the document width direction. Similarly, since the upper surface regulation guides for regulating the upper surface of the document are arranged at both side portions in the document width direction, it is possible to regulate the document substantially at three points on both side portions and the central portion.

According to the present invention having the above-mentioned structure, since the upper surface regulating guide is provided at the document feeding position together with the side guides, both sides of the document are gradually raised when the document having curl on both sides is fed. Can be regulated by the upper surface regulation guide, and both side portions of the document will not be displaced from the guide surface of the side guide, so that the skew of the document can be suppressed accordingly.

Further, according to a second aspect of the present invention, there is provided a document feeding device in which a document is loaded, and a side guide which slides in the document width direction on the paper feeding tray to regulate a side position of the document. And a feeding means for feeding the original placed in contact with the original placed on the paper feed tray, and a paper feeding means located downstream of the feeding means for feeding the delivered original into a conveying path. In a document feeder including the above, an upper face regulation guide that regulates the upper face of the document at the time of feeding the document is disposed near the feeding position where the feeding unit contacts the document, and the upper face regulation guide and the paper feeding unit are provided. A document surface pressure contact guide is arranged between the two.

According to the present invention, since the document surface pressure contact guide is arranged between the upper surface regulating guide and the sheet feeding means, the leading end portion and the trailing end portion of the original having a habit are brought into contact with this. By carrying the sheet, the leading edge of the original can be smoothly guided to the sheet feeding means, and fluttering of the trailing edge of the thick original can be suppressed.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of a document feeder according to the present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is an internal configuration diagram of an embodiment of a document feeding device mounted on a document reading device, and FIG. 2 is a perspective view when a cover of the document feeding device is opened. FIG. 3 is a partial perspective view showing an embodiment of the regulating member at the document reading position,
FIG. 4 shows a state in which a document is fed out from the document feeder. Further, FIG. 5 is a conceptual diagram showing the regulation of both sides of the document when the document is fed out, and FIG. 6 is a conceptual diagram showing the state in which the rear end of the thick paper document is regulated by the document surface pressure contact guide.

As shown in FIG. 1, the document feeder according to the present embodiment is fed with a document feeder 1 for separating and feeding the documents stacked on a paper feed tray 1 one by one, and a fed document feeder 1. The document feeder includes a conveyance unit that sends the document to the document reading position 5 of the platen 4 and sends the read document from the document reading position 5, and a paper discharge unit that discharges the document after the document reading.

As shown in FIGS. 1 and 2, the document feeder 1 presses the paper feed tray 2 on which the documents are stacked and the upper surface of the documents stacked on the paper feed tray 2 and presses them to the uppermost position. A pickup roller 6 for feeding the document, and a paper feed roller 7 and a separation roller 8 for separating and feeding the documents fed by the pickup roller 6 one by one. The pickup roller 6 is swingably connected to the paper feed roller 7 by a connecting arm 9, and both of them can be normally and reversely rotated via a one-way clutch (not shown) which can rotate in one direction. . The separation roller 8 is elastically brought into contact with the paper feed roller 7 by a spring member 10 that is pushed up from below, and can be driven by the paper feed roller 7.

The paper feed tray 2 is provided in a state of being inclined downward toward the paper feed side, and is covered by a cover 15 which can be opened and closed upward. The pickup roller 6 and the paper feed roller 7 are arranged in a recess 16 formed at the center of the lower surface of the cover 15. A guide plate 11 that slides in the document width direction is provided on the paper feed tray 2.
Are arranged. The guide plate 11 defines the size of the document in the width direction, and side guides 12 for restricting both sides of the document are provided upright on both sides. In this embodiment, the side guides 12 extend forward along both end portions of the guide plate 11, and the tip ends reach the vicinity of the paper feed port 13 on the downstream side of the pickup roller 6. Also, the side guide 12
A guide protrusion 12a is formed on the lower portion of the tip of the guide protrusion 12a, and the guide protrusion 12a slides along a guide groove 19 formed on the upper surface of the paper feed tray 2. Furthermore, side guide 1
An upper surface regulation guide 14 that regulates the upper surface of the document is provided at the upper end of 2.
Is provided. The upper surface regulation guide 14 is formed so as to horizontally project inward from the upper end of the side guide 12. The upper surface regulation guide 14 is slightly curved from the substantially central position of the side guide 12 and near the document feeding position by the pickup roller 6. It continuously extends up to.

As described above, by extending the side guide 12 to the downstream side of the pickup roller, the paper feeding roller 7
Both sides of the document will be restricted until just before it is nipped. Particularly, the tip side of the side guide 12 is the guide groove 1
Since the side guides 12 are constrained by the side guides 12, when the side guides 12 are slid in the left-right direction, the front end to the rear end are positioned almost straight along the document feeding direction. Regulation becomes more certain. Further, since the upper surface regulation guide 14 is provided at the document feeding position, the document feeding port 13 is secured, but both sides of the document are gradually raised when feeding a document with curl. Top regulation guide 14
Can be regulated with the side guides 1 on both sides of the document.
Since it does not come off from the second guide surface, the skew of the document can be suppressed accordingly.

Further, in this embodiment, FIG. 1 and FIG.
As shown in, the document surface pressure contact guide 17 is provided at an intermediate position between the pickup roller and the paper feed roller. The pressure contact guide 17 is composed of a guide rib having a tip protruding from the lower surface of the cover 15, and a guide surface 18 inclined toward the pickup roller 6 side is formed below the guide rib. As shown in FIG. 4, the document surface pressure contact guide 17 can be used even when the leading edge of the document P fed by the pickup roller 6 is curled upward.
The document surface pressure contact guide 17 can be brought into contact with the guide surface 18 and guided to the paper feed roller 7 side. Further, as shown in FIG. 6, even when the trailing edge of the document P passes through the nip point between the paper feed roller 7 and the separation roller 8, the trailing edge of the document P is guided by the guide surface 18 of the document surface pressure contact guide 17. Stable transportation is ensured by contacting with. In particular, when a strong original document such as a thick paper original document is conveyed, the rear end of the original document can be surely prevented from fluttering by suppressing the rear end of the original document from jumping up.

A document fed to a downstream side of the paper feed roller 7 in the transport unit is a document reading position 5 provided on a platen 4 of a document reading device (more specifically, a document placed below the platen). A transport path is provided for transporting the document to a position where the document is read when the document passes over the platen by the reading unit. This conveyance path is a first conveyance path 2 that bends a document and inverts it to convey it to the document reading position 5.
0 and a second transport path 21 for transporting a document that has passed through the document reading position 5. The first transport path 20 is formed in a substantially V shape by an outer guide plate 22 and an inner guide plate 23 each having a bent shape, and a document is transported into the transport path in the vicinity of the upstream side of the platen 4. A pair of conveying rollers 24 and 25 for arranging them are provided. Further, on the upstream side of the transport rollers 24 and 25, a first idler roller 26 is provided immediately downstream of the paper feed roller 7, and a second idler roller 27 is provided in the middle bent portion. These floating rollers 26, 27 have a large degree of bending of the first conveying path 20, and therefore contact friction between the original and the bent portion of the inner guide plate 23 that occurs when the original is conveyed by the conveying rollers 24, 25. In order to reduce the above, the bent portions are arranged so as to slightly project from the inner guide plate 23 side into the first transport path 20. Further, a guide piece 28 for guiding the original document onto the platen 4 is disposed in the first transport path 20 immediately downstream of the transport rollers 24 and 25.

On the other hand, the second transport path 21 is shown in FIGS.
As shown in FIG. 5, the upper side guide plate 40 and the lower side guide plate 41 that are inclined obliquely upward from the downstream end of the platen 4 are formed in a substantially linear shape, and the downstream end of the original document that has passed the original reading position 5. A pair of paper discharge rollers 43 and 44 for transporting the paper to the paper discharge tray 42 is provided. Further, a scooping guide member 45 is provided immediately downstream of the platen 4 for scooping up the document read at the document reading position 5 of the platen 4 so as to bend it and guiding it to the second transport path 21. A guide surface 46 is formed on the scooping guide member 45 so as to be continuous from the downstream side of the platen 4 toward the lower guide plate 41, and the document is guided along the guide surface 46.

As described above, there is a curved conveyance path between the conveyance rollers 24 and 25 and the paper discharge rollers 43 and 44 via the platen 4, and the platen 4 and the scooping guide member 45 define the above. A film member that presses the conveyed document toward the upper surface of the platen 4 and the scooping guide member 45 is disposed in the curved portion.

As shown in FIGS. 1 and 3, this film member is provided with a second portion along the guide surface 46 of the scoop-up guide member 45 from the upstream side of the document reading position 5 of the platen 4.
Mylar sheet 51 extending partway through the transport path 21
Composed by. The mylar sheet 51 is made of a polyester film having a thickness of about 0.1 mm, and one upstream end of the mylar sheet 51 has a frame portion 5 of a regulating member 52 described later.
3 is fixed, the other end on the downstream side becomes free,
It extends to a part of the second conveyance path 21 along the inclined surface 46 of the scooping guide member 45, and is in contact with the lower guide plate 41. The mylar sheet 51 may be configured to press a part of the conveyed document in the width direction, but as shown in FIG. 3, it is preferably configured to be wide so as to press the entire document. . That is, it is preferable that the width is larger than the width of the largest document processed by the document feeder.

On the other hand, the Mylar sheet 51 is restricted from moving upward by a restricting member 52 as shown in FIG. The restriction member 52 is a mylar sheet 51.
A substantially rectangular plate-like portion 54 that covers the above from above, a frame portion 53 that adheres and fixes the mylar sheet 51, and a restricting surface 58 that is formed on the end surface on the opposite side of the frame portion 53 and extends in the document width direction. A vertical wall piece 56 that is provided with positioning projections 55 that project from both ends of the regulation surface 58 toward the scoop-up guide member 45, and that stands up from both left and right sides of the plate-like portion 54.
Is swingably supported by the document feeder main body. Further, the regulating member 52 has a regulating surface 58 side biased toward the platen 4 side by a spring member 57 arranged between the regulating member 52 and the document conveying device. Further, since the spring bias acts on the regulation member 52 as described above, the positioning projection 55 abuts on a part of the guide surface 46 of the scooping guide member 45, and the regulation surface 58 is moved from the guide surface 46 to a predetermined position. They can be positioned at positions separated by a space S, and the mylar sheet 51 is inserted into this space S.

Therefore, when the original is scooped up from the downstream side of the platen 4 to the curved portion of the scooping guide member 45 or while the original is conveyed through the second conveying path 21, a force for pushing up the Mylar sheet 51 from the original. Even if is applied, the restriction surface 58 prevents the Mylar sheet 51 from being pushed up, so that the Mylar sheet 51 does not float up. And mylar sit 51
Since the original is conveyed while being pushed back, the original can be conveyed along the guide surface 46 of the scoop-up guide member 45 and is smoothly guided to the second conveying path 21.

Next, the operation of the document feeding device 1 having the above-mentioned structure will be described. As shown in FIGS. 1 and 4, the document P is placed on the paper feed tray 2, the guide plate 11 is slid to the left and right, and the side guides 12 regulate both sides of the document. When the original on the paper feed tray 2 is detected by the empty sensor, the drive motor is driven to rotate normally, and the pickup roller 6 pushes the upper surface of the original strongly and feeds the original on the uppermost surface. The fed original is fed to the paper feed roller 7 through the paper feed port 13, but when the original P is slightly curled, the original P is picked up by the pickup roller 6 as shown in FIG. When the central portion of the document P is fed out while being pushed out, both side portions P1 and P2 of the document P gradually rise. However, since the upper surface regulation guide 14 that regulates the upper surface of the document P regulates the rising of the document P at the document feeding position, it does not come off from the guide surface of the side guide 12. In this way, the document P is guided to the paper feed port 13 while being regulated by both the side guide 12 and the upper surface regulation guide 14, and is directly nipped between the paper feed roller 7 and the separation roller 8. Further, as shown in FIG. 4, even when the leading edge of the document P fed out by the pickup roller 6 is curled upward, it is in contact with the guide surface 18 or the like of the document surface pressure contact guide 17 and the paper feed roller. 7
And the separation roller 8 is guided to the nip position. One original is reliably separated by the paper feed roller 7 that rotates in the same direction as the pickup roller 6 and the separation roller 8 that elastically presses from below, and the separation roller 8 is driven to rotate and inside the first conveyance path 20. Be delivered to.

The document P fed to the first transport path 20 is
As shown in FIG. 6, the leading ends are nipped by the transport rollers 24 and 25, and then transported by the transport rollers 24 and 25. The first transport path 20 is formed to be largely bent,
Since the first floating roller 26 is disposed in the bent portion immediately downstream of the paper feed roller 7, the friction resistance at the bent portion is reduced and the sheet is smoothly conveyed. In addition, the second floating roller 2
Since 7 is disposed in another bent portion, the frictional resistance between the bent portion and the inner guide plate 23 is reduced, and the originals are conveyed by the conveying rollers 24 and 25 smoothly. Further, as shown in FIG. 6, the trailing edge of the document P is the paper feed roller 7.
Even when passing through the nip between the separation roller 8 and the separation roller 8, the document P
Since the rear end of the original contacts the guide surface 18 of the original surface pressure contact guide 17 to ensure stable conveyance, the rear end of the original may be changed when conveying a strong original such as a thick paper original. The pressure is regulated to reliably prevent the trailing edge of the document from fluttering.

The original moving on the first conveying path 20 by the conveying rollers 24 and 25 is the guide piece 28 and the mylar sheet 5 located immediately downstream of the conveying rollers 24 and 25.
1 is guided to the original reading position 5 on the platen 4. Then, the read document is picked up by the pressing force of the mylar sheet 51 while being pressed by the guide surface 46 of the scooping guide member 45.
It is guided to the second transport path 21 as it is, and the paper discharge roller 4
The sheet 3 is conveyed to the sheet discharge tray 42.

[Brief description of drawings]

FIG. 1 is an internal configuration diagram of a document feeder including an embodiment of a document feeder according to the present invention.

FIG. 2 is a perspective view of the document feeder according to the present invention when a cover is opened.

FIG. 3 is a partial perspective view showing an embodiment of a regulating member at a document reading position.

FIG. 4 is an explanatory view showing a state when a document is fed out from a document feeding device of the present invention.

FIG. 5 is a conceptual diagram showing regulation of both sides of the document when the document is fed out.

FIG. 6 is a conceptual diagram showing a state where the trailing edge of a thick paper document is regulated by a document surface pressure contact guide.

[Explanation of symbols]

2 paper tray 6 Pickup roller 7 Paper feed roller 8 Separation roller 12 Side guide 14 Top regulation guide 17 Original surface pressure welding guide

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Keiko Toyoda             2-3-3 Azuchi-cho, Chuo-ku, Osaka-shi, Osaka Prefecture               Minolta Co., Ltd. (72) Inventor Ryuta Komatsu             1 430 Kobayashi, Masuho-cho, Minamikoma-gun, Yamanashi Prefecture             Within ska corporation F-term (reference) 2H076 BA15 BA24 BA35 BA39 BA47                 3F343 FA03 FB02 FB03 FC12 GA02                       GB01 GC01 GD01 HA06 HE04                       HE11 HE23 KA02 KA14 KB03                       KB05 LC04 LD12 MB03 MB12                       MB14 MC26

Claims (4)

[Claims] 1. A paper feed tray on which a document is stacked, a side guide that slides in the document width direction on the paper feed tray to regulate a side position of the document, and a document placed on the paper feed tray. In a document feeding device including a feeding unit that comes into contact and feeds a document, and a sheet feeding unit that is located on the downstream side of the feeding unit and feeds the fed document to a conveyance path, the feeding unit is a document source. A document feeding device, wherein the side guide is extended downstream of a feeding position in contact with the document feeding device, and an upper surface regulating guide for regulating a position of an upper surface of the document at the time of feeding the document is arranged near the feeding position. 2. A paper feed tray on which a document is stacked, a side guide that slides in the document width direction on the paper feed tray to regulate the side position of the document, and a document placed on the paper feed tray. In a document feeding device including a feeding unit that comes into contact and feeds a document, and a sheet feeding unit that is located on the downstream side of the feeding unit and feeds the fed document to a conveyance path, the feeding unit is a document source. An upper surface regulation guide for restricting the upper surface of the original when the original is fed out, and an original surface pressure contact guide disposed between the upper surface regulation guide and the paper feeding means. Document feeder that does. 3. The document feeder according to claim 1, wherein the upper surface regulation guide is provided on the side surface of the side guide in the vicinity of the feeding position. 4. The document feeding apparatus according to claim 2, wherein the document surface pressure contact guide is arranged at a substantially central portion of the sheet feeding tray in the document width direction.