This application claims the benefit of Taiwan application Serial No. 96146602, filed Dec. 6, 2007, the subject matter of which is incorporated herein by reference.
BACKGROUND OF THE INVENTION
1. Field of the Invention
The invention relates in general to a paper feeder and the image processing apparatus using the same, and more particularly to a paper feeder and an image processing apparatus of aligning one edge of a sheet against a paper guide while feeding the sheet in a forward direction parallel to the paper guide.
2. Description of the Related Art
Automatic document feeder (ADF) has been widely used in various computer peripherals or office-use electronics, such as printer, copier, scanner and multifunction products. The ADF device replaces manual operation of the page separation and largely increases the operation efficiency.
Many of the current ADF's use a roller to transport the sheets of paper or documents and further use two side-edge registration guides to align the sheets of paper such that each of the sheets will be fed into the ADF in a direction parallel to the side-edge registration guides. However, when the stack contains sheets of different sizes, the side edges of the small-sized sheets will not come into contact with one or both of the side-edge registration guides. Thus, when the small-sized sheets are conveyed, the document or paper may easily tilt due to the non-uniform force applied thereto, hence resulting in operation errors or skew in scan images.
SUMMARY OF THE INVENTION
The invention is directed to a paper feeder and the image processing apparatus using the same. A frictional force is provided to the fed-in sheets such that the tilt of the sheet of paper can be corrected and the sheet of paper is fitting for subsequent processing.
According to a first aspect of the present invention, a paper feeder including a feeding plate, a paper guide, a paper-feeding unit and a friction provider is provided. The feeding plate is used for supporting at least one sheet of paper. The paper guide is disposed on a side of the feeding plate for aligning the sheet of paper to move. The paper-feeding unit is disposed at a paper-feeding end of the feeding plate for conveying the sheet of paper placed on the feeding plate. The friction provider is disposed on one lateral side of the paper-feeding unit, for increasing the friction between the sheet of paper and the surface of the feeding plate, and the paper guide is disposed on the other lateral side of the paper-feeding unit.
According to a second aspect of the present invention, an image processing apparatus including an image processing region, an image processing module and a paper feeder is provided. The image processing module is positioned within the image processing region. The paper feeder feeds a paper to the image processing region for the image processing module to process with. The paper feeder includes a feeding plate, a paper guide, a paper-feeding unit and a friction provider. The feeding plate is for supporting at least one sheet of paper. The paper guide is disposed on a side of the feeding plate for aligning the sheet of paper. The paper-feeding unit is disposed at a paper-feeding end of the feeding plate for conveying the sheet of paper placed on the feeding plate. The friction provider is disposed on one lateral side of the paper-feeding unit, for increasing the friction between the sheet of paper and the surface of the feeding plate, and the paper guide is disposed on the other lateral side of the paper-feeding unit.
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
FIG. 1 shows a partial view of an image processing apparatus using a paper feeder according to a preferred embodiment of the invention;
FIG. 2 shows a partial view of a paper feeder according to the preferred embodiment of the invention; and
FIG. 3 shows a partial view of the friction provider in FIG. 2 and an upper cover according to the preferred embodiment of the invention.
DETAILED DESCRIPTION OF THE INVENTION
Referring to FIG. 1, a partial view of an image processing apparatus using a paper feeder according to a preferred embodiment of the invention is shown. The image processing apparatus 10 includes a main body 50 having an image processing region 50a, wherein an image module 52 is positioned in the image processing region 50a. If the image processing apparatus 10 is a scanner, then the image processing module 52 is a scanning module. If the image processing apparatus 10 is a printer, then the image processing module 52 is a printing module. In the present embodiment of the invention, the image processing apparatus 10 is exemplified as a scanner. The paper feeder 100 is disposed on the main body 50 for feeding a sheet of paper (not illustrated) to the image processing region 50a. The paper feeder 100 includes a feeding plate 120 used for supporting the sheet of paper. The paper guide 130, such as a fixed knob, is disposed on one lateral side of the feeding plate 120 for aligning the sheet of paper. The paper-feeding unit 140 is disposed at the paper-feeding end of the feeding plate 120 for conveying the sheet of paper placed on the feeding plate. In the present embodiment of the invention, the paper-feeding unit 140 is a rubber roller for example. The friction provider 150 is disposed on one lateral side of the paper-feeding unit 140, and the paper guide 130 is disposed on the other lateral side of the paper-feeding unit 140. The friction provider 150 is used for increasing the friction between the sheet of paper and the surface of the feeding plate 120 so as to align the sheet of paper with the paper guide 130 while the sheet of paper is conveyed by the paper-feeding unit 140. In the present embodiment of the invention, the friction provider 150 preferably is disposed adjacent to the paper-feeding unit 140. Although the paper feeder 100 is used in a scanner as an example, the paper feeder 100 can also be used in a printer, a copier, a facsimile or a multi-function product (MFP). The image processing apparatus using a paper feeder according to a preferred embodiment of the invention is applicable to any office equipment having an automatic document feeder (ADF).
Referring to FIG. 2, a partial view of a paper feeder according to the preferred embodiment of the invention is shown. As indicated in FIG. 2, the friction provider 150 can be a single suppressor, or a friction pad having high friction coefficient. In the present embodiment of the invention, the friction provider 150 includes both a suppressor 152 and a friction pad 154, which are respectively viewed as a first friction provider and a second friction provider. Referring to FIG. 3, a partial view of the friction provider in FIG. 2 and an upper cover according to the preferred embodiment of the invention is shown. In the present embodiment of the invention, the paper feeder 100 further includes an upper cover 105 disposed above the feeding plate 120, and the suppressor 152 has an elastic piece 152b disposed on the upper cover 105 and projected from the upper cover 105 towards the feeding plate 120 to increase the friction between the sheet of paper and the surface of the feeding plate 120. In the present embodiment of the invention, the suppressor 152 is formed by a roller 152a and an elastic piece 152b, wherein the roller 152a is disposed on the elastic piece 152b and the elastic piece 152b is disposed on the upper cover 105 to provide the roller 152a with an elastic force for suppressing the sheet of paper. The roller 152a can be an idle roller, which merely provides a weight or an exerting force on the sheet of paper, to increase the friction between the sheet of paper and the surface of the feeding plate 120. The friction pad 154 is disposed on the main body 110 of the paper feeder. The friction pad 154 and the suppressor 152a together contact the sheet of paper on the opposite side and the friction pad 154 provides the sheet of paper with another frictional force. Besides, the friction provider 150 can be formed by a surface within an area of the feeding plate 120, which has a higher friction coefficient than that of the surface of the feeding plate 120 outside the area. For example, the surface of the feeding plate 120 near the paper-feeding unit 150 is ground into a rough surface. However, the technology of the invention is not limited to the above disclosure. For example, the friction pad 154 can be disposed on the upper end of the feeding plate 120. Taking FIG. 1 for example, the top right corner of the paper-feeding unit 140 is used as a reference point, and a region I and a region II are formed accordingly. The friction pad 154 can be disposed in the region I or the region II of the feeding plate 120. Likewise, another friction provider, which may include the elastic piece or the roller, can be correspondingly disposed in the region I or the region II with respect to the friction pad 154. Also, two sets or more than two sets of friction providers 150 can be disposed in the region I and the region II. The sheet of paper will be aligned properly as long as the paper-feeding unit 140 is disposed between the friction provider 150 and the paper guide 130. The friction provider can merely use the suppressor 152 or the friction pad 154.
Also, as indicated in FIG. 1, the image processing apparatus 10 further includes another paper guide 160 movably disposed on the feeding plate 120 for guiding the sheet of paper. Another paper guide 160 is disposed on the same lateral side of the paper-feeding unit 140 as the friction provider 150 is disposed, for aligning the sheet of paper. In the present embodiment of the invention, the paper guide 160 slides crosswise on the feeding plate 120 to accommodate sheets of different sizes.
The friction provider 150 provides a frictional force while the sheet of paper is conveyed by the paper-feeding unit 140. As for the sheet of paper having a width smaller than the distance between the paper guide 130 and the paper guide 160, since the friction provider 150 in the present invention provides a frictional force for adjusting the sheet of paper to shift towards the paper guide 130 during the movement of the sheet of paper, the sheet of paper does not tilt when being conveyed. As the paper guide 130 can contact the sheet of paper to restrict the range of movement of the sheet of paper, the sheet of paper will be normally fed into the image processing module 52 for subsequent processing.
Referring to FIG. 2, the paper feeder 100 further includes a separation pad 170 correspondingly disposed opposite the paper-feeding unit 140. In this embodiment, the paper feeder 100 is a bottom-feeding type feeder, i.e., the sheet at the bottom of a stack is being fed first. Thus, the paper-feeding unit 140 is disposed on the feeding plate 120 and the separation pad 170 is placed above the paper-feeding unit 140. When the sheets of paper on the feeding plate 120 are conveyed by the paper-feeding unit 140, the separation pad 170 is used for contacting the upper sheets of paper to separate the upper sheets from the to-be-scanned sheet.
The paper feeder and the image processing apparatus using the same disclosed in the embodiments of the invention use a friction provider to increase the friction between the sheet of paper and the feeding plate. When the sheet tilts towards a restriction-free direction, the frictional force will deskew the sheet and slightly rotate the sheet back to an appropriate position such that the sheet is properly fed in and errors in operation can be avoided.
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.
Patent Application
20090146365
