Automatic document-feeding apparatus

Abstract

An automatic document-feeding apparatus is disclosed. The automatic document-feeding apparatus comprises means for picking up and transporting document sheets, means for separating document sheets into a sequence of transportation, and means for pressing document sheets. The means for picking up and transporting document sheets contact and transport document sheets and the means for separating document sheets comprise an incline plane used to receive and support the document sheet being transported from the means for picking up and transporting document sheets. The means for pressing document sheets press the document sheets to keep the document sheets and the incline plane in tight contact.

Description

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The present invention relates to an automatic document-feeding apparatus, and more particularly to an automatic document-feeding apparatus with superior capability of document pagination.

[0003] 2. Description of the Related Art

[0004] It is publicly known to use a document feeding apparatus so-called as an automatic document feeder (ADF) in order to supply automatically a document to a document reading portion in an image forming apparatus. The automatic document feeder (ADF) is a useful device for documenting image input system such as image scanner. In the application of the so-called “Paper-Feed” image input device, the automatic document feeder functions to transport page by page documents containing image data, into the scanning area of the image input device.

[0005] FIG. 1 shows the basic structure of a conventional automatic document feeder. As shown in the figure, the automatic document feeder comprises a pagination roller 102, a pickup roller 104 and a retard pad 108. The retard pad 108 is pressed against the pagination roller 102 by a pressure spring 106. A stack of documents 110 are mounted on bottom of the pickup roller 104.

[0006] Ideally, when the pickup roller 104 starts to rotate, a document 110 at the top of the stack of the documents is fetched by the pickup roller 104 to the retard pad 108 and all documents other than the one at the top of the stack are stopped since only the one at the top of the stack can contact the pickup roller 104. The document at the top of the stack is then transported to the retard pad 108 and under the pagination roller 102 by the pickup roller 104.

[0007] However, the conventional automatic document feeder described above indeed presents a problem which would harm the function of an image scanner. The problem is that the continuous fed documents are not separated well when the pickup roller 104 picks up and sends more than one document sheet once. That is, more than two document sheets are transported to the retard pad 108 and under the pagination roller 102 usually. The excess fed document sheets undoubtedly would impede the normal operation the whole machine since the excess fed document sheets could hinder the feeding of the following document sheets or jam in the automatic document feeder. Therefore, it is desirable to provide an automatic document-feeding apparatus with superior capability of document pagination to overcome the problem of the prior art.

SUMMARY OF THE INVENTION

[0008] It is therefore an object of the invention to provide an automatic document-feeding apparatus with superior capability of document pagination.

[0009] It is another object of this invention to provide a reliable automatic document-feeding apparatus.

[0010] To achieve these objects, and in accordance with the purpose of the invention, the invention provide an automatic document-feeding apparatus with superior capability of document pagination. In one embodiment of this invention, the apparatus comprises means for picking up and transporting document sheets, means for separating document sheets into a sequence of transportation, and means for pressing document sheets. The means for picking up and transporting document sheets contact and transport document sheets and the means for separating document sheets comprise an incline plane used to receive and support the document sheet being transported from the means for picking up and transporting document sheets. The means for pressing document sheets press the document sheets to keep the document sheets and the incline plane in tight contact.

[0011] In another embodiment of this invention, the automatic document-feeding apparatus of this invention comprises means for picking up document sheets, means for separating document sheets into a sequence of transportation, means for pressing document sheets, and means for transporting document sheets. The means for picking up document sheets contact and pick up document sheets and the means for separating document sheets comprise an incline plane used to receive and support the document sheet being transported from the means for picking up document sheets. The means for pressing document sheets press the document sheets to keep the document sheets and the incline plane in tight contact and the means for transporting document sheets receive and transport the document sheets being transported from the means for separating document sheets.

[0012] It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The foregoing aspects and many of the attendant advantages of this invention will become more readily appreciated as the same becomes better understood by reference to the following detailed description, when taken in conjunction with the accompanying drawings, wherein:

[0014] FIG. 1 shows the basic structure of a conventional automatic document feeder; and

[0015] FIG. 2 shows an automatic document-feeding apparatus of this invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT

[0016] It is to be understood and appreciated that the apparatus described below do not cover a complete system. The present invention can be practiced in conjunction with various hardware that are used in the art, and only so much of the commonly practiced components and steps are included herein as are necessary to provide an understanding of the present invention.

[0017] The present invention will be described in detail with reference to the accompanying drawings. It should be noted that the drawings are in greatly simplified form.

[0018] Referring to FIG. 2, an automatic document-feeding apparatus 200 of this invention is shown. In one embodiment of this invention, the automatic document-feeding apparatus 200 comprises means for picking up and transporting document sheets, means for separating document sheets into a sequence of transportation and means for pressing document sheets comprising a pressing plate 212. The means for picking up and transporting document sheets comprise rollers 202 and 204 as well as at least one motor (not shown) driving the rollers 202 and 204. The roller 204 comprising a rubber roller is used to contact, pick up and drive the top sheet of a stack of document sheets 210. The roller 202 comprising a rubber roller is used to transport the document sheet from the roller 204 to the scanning area of an image scanner. The roller 202 and 204 could be drove by a single motor or two motors individually and roll synchronously. The means for separating document sheets into a sequence of transportation comprises a supporting pad 208 as well as a plurality of spring 206 pushing the supporting pad 208 against to the roller 202. The pressing plate 212 provides the document sheets 210 with a downward pressing force so that the document sheets 210 can be pressed and the front edges of the document sheets 210 can keep a tight contact with the supporting pad 208. The pressing plate 212 can be pivoted on a pivot 205 which is also the pivot of the roller 204. The pressing plate 212 can also be mounted somewhere else. The supporting pad 208 preferably comprises an incline plane 208a and a cave surface 208b. The incline plane 208a provides the document sheets 210 with an upward pushing force and a separating force so that the top one of the document sheets 210 can keep a tight contact with the pressing plate 212 and the document sheets 210 can be separated into a sequence of transportation while the roller 204 rolls. The cave surface 208b provides the document sheet 210 being transported with a support so that the document sheet 210 can contact with the roller 202 tightly. The cave surface 208b contacts the roller 202 while no document sheet is inserted therebetween so as to provide the document sheet 210 with a friction force. The springs 206 support and push the supporting pad 208.

[0019] Other embodiments of the invention will appear to those skilled in the art from consideration of the specification and practice of the invention disclosed herein. It is intended that the specification and examples to be considered as exemplary only, with a true scope and spirit of the invention being indicated by the following claims.

Claims

1. An automatic document-feeding apparatus, said apparatus comprising: means for picking up and transporting document sheets, said means for picking up and transporting document sheets contact and transport document sheets; means for separating document sheets into a sequence of transportation, said means for separating document sheets comprise an incline plane used to receive and support the document sheet being transported from said means for picking up and transporting document sheets; and means for pressing document sheets, said means for pressing document sheets press the document sheets to keep the document sheets and said incline plane in tight contact.

2. The apparatus according to claim 1, wherein said means for picking up and transporting document sheets comprise a roller for picking up document sheets and a roller for transporting document sheets, said roller for transporting document sheets receives document sheets from said roller for picking up document sheets.

3. The apparatus according to claim 2, wherein said roller for picking up document sheets and said roller for transporting document sheets are drove by a motor.

4. The apparatus according to claim 2, wherein said roller for picking up document sheets and said roller for transporting document sheets are drove by two motors individually.

5. The apparatus according to claim 2, wherein said rollers comprise rubber rollers.

6. The apparatus according to claim 1, wherein said means for pressing document sheets comprise a pressing plate

7. An automatic document-feeding apparatus, said apparatus comprising: means for picking up document sheets, said means for picking up document sheets contact and pick up document sheets; means for separating document sheets into a sequence of transportation, said means for separating document sheets comprise an incline plane used to receive and support the document sheet being transported from said means for picking up document sheets; means for pressing document sheets, said means for pressing document sheets press the document sheets to keep the document sheets and said incline plane in tight contact; and means for transporting document sheets, said means for transporting document sheets receive and transport the document sheets being transported from said means for separating document sheets.

8. The apparatus according to claim 7, wherein said means for picking up document sheets comprise a roller.

9. The apparatus according to claim 7, wherein said means for separating document sheets comprises a supporting pad and springs pushing said supporting pad against said means for pressing document sheets.

10. The apparatus according to claim 7, wherein said means for pressing document sheets comprise a pressing plate.

11. The apparatus according to claim 7, wherein said means for transporting document sheets comprise a roller.

12. An automatic document-feeding apparatus, said apparatus comprising: a first roller, said first roller contacts and picks up document sheets; a supporting pad, said supporting pad comprises an incline plane used to receive and support the document sheet being transported from said first roller and a cave surface; means for pressing document sheets, said means for pressing document sheets press the document sheets to keep the document sheets and said incline plane in tight contact; and a second roller contacting said cave surface, said second roller receives and transports the document sheets being transported from said incline plane.

13. The apparatus according to claim 12, wherein said first roller comprises a rubber roller.

14. The apparatus according to claim 12, wherein said supporting pad comprises a rubber pad and springs pushing said rubber pad against said second roller and said means for pressing document sheets.

15. The apparatus according to claim 12, wherein said means for pressing document sheets comprise a pressing plate.

16. The apparatus according to claim 12, wherein said second roller comprises a rubber roller.

17. The apparatus according to claim 12, wherein said first and second rollers are drove by a single motor.

18. The apparatus according to claim 12, wherein said first and second rollers are drove by two motors individually.