SHEET FEEDING APPARATUS AND PAPER SEPARATION DEVICE THEREOF
A sheet feeding apparatus includes an input tray, a paper picking device, and a paper separation device. The input tray is for placing a plurality of papers. The paper picking device is for performing a paper picking operation on the papers. The paper separation device, including a paper separation surface contacting with the papers placed on the paper tray, is for applying a paper separation force on each of the papers as fed in. When the paper picking device performs the paper picking operation on each of the papers, the paper separation forces applied on the papers are decreased as their paper separation paths are increased.
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This application claims the benefit of Taiwan application Serial No. 94122429, filed on Jul. 1, 2005, the subject matter of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION1. Field of the Invention
The invention relates in general to a sheet feeding apparatus and paper separation device thereof, and more particularly to a sheet feeding apparatus, which can apply suitable paper separation forces on the fed-in papers according to the amount of the papers, and paper separation device thereof.
2. Description of the Related Art
Generally, in a printer, papers are fed in for print via a sheet feeding mechanism. In order to meet the requirements for papers having various feeding features, a paper separation device is usually configured in the sheet feeding mechanism to separate the papers, and the papers can thus be fed into the printer piece by piece.
As described above, when the amount of papers 111 decreases, and the uppermost paper 111 is moved from the point G to the point H as shown in
In order to provide enough forces for sliding the papers and prevent the paper gliding issue, a paper separator of a printer is disclosed in the U.S. Pat. No. 6,536,757 as shown in
As shown in
However, the above-mentioned paper separator 200 has the following disadvantages:
1. Owing that the paper separator 200 uses the saw structures 212, 224, 226 on the friction projection 210 and the jack buckler 222 to generate paper separation forces, the resisting force for the fed-in papers 211 is relatively increased and the motor miss-step risk is thus enhanced.
2. Owing that the papers 211 stay at one side of the guide projection 222 at the beginning of paper feeding, the path for paper feeding is increased, thereby enlarging the mechanism size and mechanical resistance force in feeding papers.
3. When the amount of papers decreases or papers of higher rigidity are used for print, the paper separation forces are not reduced accordingly. Therefore, the above-mentioned miss-feed and motor miss-step issues cannot be prevented.
4. Except for the friction projection 210 served as a paper separation device, the paper separator 200 uses an extra jack buckler 220 to prevent the paper gliding issue, which increases, however, the mechanism cost.
SUMMARY OF THE INVENTIONIt is therefore an object of the invention to provide a sheet feeding apparatus and paper separation device thereof. By a suitable design of the surface structure of the paper separation device, the paper separation forces applied on the fed-in papers by the surface of the paper separation device are decreased as the paper separation paths of the papers are increased. Therefore, the paper gliding and the multi-feed issues easily generated in a large paper amount and the miss-feed and motor miss-step issues easily generated in a small paper amount can be prevented.
The invention achieves the above-identified object by providing a paper separation device used in a sheet feeding apparatus. The sheet feeding apparatus includes an input tray for placing a number of papers The paper separation device includes a paper separation surface. The paper separation surface, contacting with the papers placed on the input tray, is for applying a paper separation force on each of the papers as fed in. The paper separation forces applied on the fed-in papers are decreased as their paper separation paths are increased.
The invention achieves the above-identified object by providing a sheet feeding apparatus including an input tray, a paper picking device, and a paper separation device. The input tray is for placing a plurality of papers. The paper picking device is for performing a paper picking operation on the papers. The paper separation device, including a paper separation surface contacting with the papers placed on the paper tray, is for applying a paper separation force on each of the papers as fed in. When the paper picking device performs the paper picking operation on each of the papers, the paper separation forces applied on the papers are decreased as their paper separation paths are increased.
Other objects, features, and advantages of the invention will become apparent from the following detailed description of the preferred but non-limiting embodiments. The following description is made with reference to the accompanying drawings.
BRIEF DESCRIPTION OF THE DRAWINGS
Referring to
Referring to
As shown in
Besides, as shown in
It is noted that although it is exemplified that the sliding sides 333a of the saw strips 333 are parallel to each other and the inclined angles a of the threshold sides 333b are decreased along the paper feeding direction in the first example as shown in
Referring to
As shown in
It is noted that although it is exemplified in the second example that the threshold sides 533b of the saw strips 533 are in parallel and the depth H of the gaps between two adjacent saw strips 533 is increased along the paper feeding direction Lp, in the paper separation surface 532 of the invention, the threshold sides 533b of the saw strips 533 can also be not in parallel, and the height h of the saw strips 333 can also be different. As long as the angles between two adjacent saw strips 533 (the angles between the adjacent threshold sides 533b and the sliding sides 533a) are decreased along the paper feeding direction, and the depth H of the gaps between two adjacent saw strips 533 is increased along the paper feeding direction Lp, all the alternatives can still prevent the paper gliding and multi-feed issues happened in a large paper amount and small paper separation path as well as the miss-feed and motor miss-step issues happened in a small paper amount and large paper separation path.
As described above, although it is exemplified that the inclined angles a are decreased or the depth of the saw gaps is increased along the paper feeding direction Lp in the invention, the invention is not limited thereto. In the paper separation device, the saw angles of the paper separation surface can also be increased along the paper feeding direction or the depth of the saw gaps can also be decreased along the paper feeding direction. As long as the paper separation forces are decreased as the paper separation paths of the fed-in papers are enlarged, the multi-feed and miss-feed issues can be prevented. Therefore, all these are not apart from the scope of the invention.
According to the two examples mentioned above, although it is exemplified that the saw strips (333 or 533) have the same height h and different saw angles a or gap depth H, the paper separation surface 332 of the invention can also have saw strips of different height or have certain saw strips of the same height and the rest of different height. As long as the saw height and accordingly the saw gap depth is increased along the paper feeding direction while the angles between two adjacent saws are the same or are decreased along the paper feeding direction, the above-mentioned paper separation issue can be prevented. The saw height, saw angles, and saw gap depth of the paper separation surface 332 can be even designed suitably so that the paper separation force applied on the papers by the paper separation surface can be decreased as the paper amount is reduced, thereby achieving the purpose of preventing the above-mentioned paper separation issues.
In addition, although the paper separation surface 332 having saw strips 333 or 533 is taken as an example in the invention, the paper separation surface 332 of the paper separation device 330 in the invention can also includes a number of circular protrusions 633 or some saw strips (333 or 533) and some circular protrusions 633 having the same height h as shown in
Although the paper separation surface 332 having saw strips 333, 533, or circular protrusions 633, 733 is taken as an example in the invention, the paper separation surface 332 of the paper separation device 330 in the invention can also include other protrusions of a regular shape or an irregular shape. The paper separation surface can also even be surface-processed suitably to provide the paper separation force required for the papers in a surface friction way. As long as the paper separation forces applied on the fed-in papers are decreased as their paper separation paths are increased, the papers gliding and multi-feed issues easily happened in a large paper amount or the miss-feed and motor miss-step issues easily happened in a small paper amount can be prevented. Therefore, all these will not depart from the scope of the invention.
The sheet feeding apparatus and paper separation device thereof disclosed by the above-mentioned embodiment of the invention has the following advantages:
1. The invention can prevent the paper gliding and motor miss-step issues by a direct surface structure design of the paper separation device without using extra auxiliary devices.
2. By decreasing the paper separation forces applied on the papers as their paper separation paths are increased, the invention can prevent the paper gliding and multi-feed issues easily happened in a large paper amount and the miss-feed and motor miss-step issues easily happened in a small paper amount.
3. By using the paper separation surface to provide a smaller paper separation force as the paper has a larger paper separation path, the invention can prevent the motor miss-step issue or the miss-feed issue happened as feeding the papers of higher rigidity.
While the invention has been described by-way of example and in terms of a preferred embodiment, it is to be understood that the invention is not limited thereto. On the contrary, it is intended to cover various modifications and similar arrangements and procedures, and the scope of the appended claims therefore should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements and procedures.
Claims
1. A paper separation device, used in a sheet feeding apparatus, the sheet feeding apparatus comprising an input tray for placing a plurality of papers, the paper separation device comprising:
- a paper separation surface, contacting with the papers placed on the input tray, for applying a paper separation force on each of the papers as fed in;
- wherein the paper separation forces applied on the fed-in papers are decreased as their paper separation paths are increased.
2. The paper separation device according to claim 1, wherein the paper separation surface comprises a plurality of protrusions arranged along a paper feeding direction for providing the paper separation force.
3. The paper separation device according to claim 2, wherein the protrusions of a regular or an irregular shape have the same or different height.
4. The paper separation device according to claim 2, wherein the protrusions are a plurality of saw strips.
5. The paper separation device according to claim 4, wherein the size of saw gaps between the tops of two adjacent saws is decreased along the paper feeding direction.
6. The paper separation device according to claim 5, wherein each of the saw strip has a first surface facing to the paper feeding direction and a second surface facing against the paper feeding direction, the first surfaces are arranged in parallel, and the second surfaces have decreased inclined angles against a vertical line of the paper separation surface along the paper feeding direction.
7. The paper separation device according to claim 4, wherein the saw strips have gap depth increased along the paper feeding direction.
8. The paper separation device according to claim 7, wherein each of the saw strips has a third surfaces facing to the paper feeding direction and a forth surface facing against the paper feeding direction, the third surfaces are arranged in parallel, and the depth of gaps between the bottoms and the tops of the forth surfaces is decreased along the paper feeding direction.
9. The paper separation device according to claim 2, wherein the protrusions are a plurality of circular protrusions.
10. The paper separation device according to claim 9, wherein the size of gaps between two adjacent circular protrusions is decreased along the paper feeding direction.
11. The paper separation device according to claim 9, wherein the depth of gaps between two adjacent circular protrusions are increased along the paper feeding direction.
12. A sheet feeding apparatus, comprising:
- an input tray, for placing a plurality of papers;
- a paper picking device, for performing a paper picking operation on the papers; and
- a paper separation device, comprising a paper separation surface contacting with the papers placed on the paper tray, for applying a paper separation force on each of the papers as fed in;
- wherein when the paper picking device performs the paper picking operation on each of the papers, the paper separation forces applied on the papers are decreased as their paper separation paths are increased.
13. The sheet feeding apparatus according to claim 12, wherein the paper separation surface comprises a plurality of protrusions arranged along a paper feeding direction for providing the paper separation force.
14. The sheet feeding apparatus according to claim 13, wherein the protrusions of a regular or an irregular shape have the same or different height.
15. The sheet feeding apparatus according to claim 13, wherein the protrusions are a plurality of saw strips.
16. The sheet feeding apparatus according to claim 15, wherein the size of saw gaps between two adjacent saw strips is decreased along the paper feeding direction.
17. The sheet feeding apparatus according to claim 16, wherein each of the saw strips has a first surface facing to the paper feeding direction and a second surface facing against the paper feeding direction, the first surfaces are arranged in parallel, and the second surfaces have decreased inclined angles against a vertical line of the paper separation surface along the paper feeding direction.
18. The sheet feeding apparatus according to claim 15, wherein the depth of gaps between two adjacent saws is increased along the paper feeding direction.
19. The sheet feeding apparatus according to claim 18, wherein each of the saw strips has a third surface facing to the paper feeding direction and a forth surface facing against the paper feeding direction, the third surfaces are arranged in parallel, and the depth of gaps between the bottoms and the tops of the forth surfaces is decreased along the paper feeding direction.
20. The sheet feeding apparatus according to claim 13, wherein the protrusions are a plurality of circular protrusions.
21. The sheet feeding apparatus according to claim 20, wherein the size of gaps between two adjacent circular protrusions is decreased along the paper feeding direction.
22. The sheet feeding apparatus according to claim 21, wherein the depth of gaps between two adjacent circular protrusions is increased along the paper feeding direction.
Type: Application
Filed: May 5, 2006
Publication Date: Jan 4, 2007
Applicant: BENQ CORPORATION (Taoyuan Shien)
Inventors: Hai-Tao Ma (Ningxia Province), Ming-Jie Zhao (Shandong Province)
Application Number: 11/381,775
International Classification: B65H 11/00 (20060101);