Patent Application
20090295062
This application claims priority of No. 097119459 filed in Taiwan R.O.C. on May 27, 2008 under 35 USC 119, the entire content of which is hereby incorporated by reference.
1. Field of the Invention
The invention relates to an automatic sheet feeder and a scan apparatus, and more particularly to an automatic sheet feeder with assemblies for transporting a sheet at different speeds, and a scan apparatus using the automatic sheet feeder.
2. Related Art
A conventional automatic sheet feeder usually has a sheet detector or a plurality of sheet detectors for detecting a trailing edge and a leading edge of a sheet. Then, the sheet-fed roller in the feeder is controlled and timely stopped according to the signal outputted from the sheet detector, such that a delay in the time for initiating the feeding of a next sheet is effected and a sequence of sheets are separated by gaps between them. The sheets are scanned intermittently by a scan module, and discrete images of the sheets are thus generated.
However, the automatic sheet feeder comprising the sheet detector has a complicated control circuit, while the hardware cost thereof is increased. Moreover, the automatic sheet feeder for combining with a flatbed scanner usually is the U-type automatic sheet feeder, which needs more rollers and components, and of which the manufacturing cost and the price are relatively high.
Thus, it is an important subject of the invention to provide an automatic sheet feeder with fewer components and of a lower cost.
It is therefore an object of the invention to provide an automatic sheet feeder with fewer components and of a lower cost, which has a transporting mechanism for transporting a sheet at different speeds. The difference in speed will generate references for a subsequent image processing procedure, that is, page separation, by which a discrete image of the sheet can be obtained without the sheet detector and related circuits.
To achieve the above-identified object, the invention provides an automatic sheet feeder comprising a sheet passageway, an opening formed in the sheet passageway and a sheet transporting mechanism. The sheet transporting mechanism transports a sheet through the sheet passageway. The sheet transporting mechanism comprises a first transporting assembly and a second transporting assembly, which is disposed downstream of the first transporting assembly. The first transporting assembly transports the sheet to the opening at a first speed, and the second transporting assembly transports the sheet away from the opening at a second speed higher than the first speed.
The invention also provides a scan apparatus including an automatic sheet feeder and a scan module. The automatic sheet feeder comprises a sheet passageway, an image-processing area and a sheet transporting mechanism. The sheet transporting mechanism sequentially transports a first sheet and a second sheet through the sheet passageway. The sheet transporting mechanism comprises a first transporting assembly and a second transporting assembly disposed downstream of the first transporting assembly. The first transporting assembly transports the first sheet and the second sheet to the image-processing area at a first speed, and the second transporting assembly transports the first sheet and the second sheet away from the image-processing area at a second speed higher than the first speed. The scan module continuously scans the first sheet and the second sheet within the image-processing area and generates a continuous image. The continuous image comprises a first sheet image corresponding to the first sheet, a second sheet image corresponding to the second sheet and a gap image corresponding to a gap between the first sheet and the second sheet.
The invention can continuously scan multiple sheets without using a sheet detector and generate gaps for page separation and corresponding gap images. The gap images can be used as references in a subsequent image processing procedure so that the continuous image can be divided into separate pages of images, each corresponding to an individual sheet.
Further scope of the applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description.
The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention.
The present invention will be apparent from the following detailed description, which proceeds with reference to the accompanying drawings, wherein the same references relate to the same elements.
The base 10 may be composed of a single member or a plurality of members and has a sheet passageway 11, which may be formed by a plurality of guide plates. The sheet passageway 11 can be U-shaped or L-shaped.
The sheet transporting mechanism 20 disposed on the base 10 transports the sheet S through the sheet passageway 11. In this embodiment, the sheet transporting mechanism 20 includes a first transporting assembly 22 and a second transporting assembly 24, which is disposed downstream of the first transporting assembly 22. The downstream side is determined based on a moving direction of the sheet S. That is, the sheet S is at first transported by the first transporting assembly 22 and then by the second transporting assembly 24.
The automatic sheet feeder 1 has an opening 12, which is formed in the sheet passageway 11 and between the first transporting assembly 22 and the second transporting assembly 24, and the opening 12 exposes a portion of the sheet S. The first transporting assembly 22 transports the sheet S to the opening 12 at a first speed V1, and the second transporting assembly 24 transports the sheet S away from the opening 12 at a second speed V2 higher than the first speed V1. When multiple sheets are transported sequentially, the difference between the second speed V2 and the first speed V1 will generate gaps between successive sheets.
In addition, the automatic sheet feeder 1 may further include a feeding tray 30. The feeding tray 30, disposed on the base 10 and connected to the sheet passageway 11, supports the sheet S or a stack of sheets including the sheet S. The first transporting assembly 22 transports the sheet S into the sheet passageway 11 from the feeding tray 30. It is to be noted that the feeding tray 30 may be omitted under the considerations of the cost and the space. In this case, the user can support the stack of sheets by his/her hand so that the sheets can be fed.
In this embodiment, the first transporting assembly 22 includes a first roller 221 and a frictional element (e.g., a friction pad) 222 located opposite the first roller 221, and the first roller 221 and the frictional element 222 separate the sheet S from the stack of sheets and transport the sheet S into the sheet passageway 11 and to the opening 12, wherein the first roller 221 is disposed in the sheet passageway 11. The first roller 221 may cooperate with another idle roller (not shown) to transport the sheet S.
Similarly, the second transporting assembly 24 includes a second roller 241 disposed in the sheet passageway 11, and the second roller 241 transports the sheet S away from the opening 12 and out of the sheet passageway 11. The second transporting assembly 24 can include an idle roller 242, and the second roller 241 and the idle roller 242 cooperate with each other to transport the sheet S. The first roller 221 and the second roller 241 may be driven by the same power source (e.g., a motor) 13 or different power sources.
In order to obtain the difference between the second speed V2 and the first speed V1, the first roller 221 and the second roller 241 are rotated at different angular velocities in the case that outer diameters of the first roller 221 and the second roller 241 are equal. Alternatively, the first roller 221 and the second roller 241 are rotated at the same angular velocity, in the case that outer diameters of the first roller 221 and the second roller 241 are unequal.
In order to make the sheet S be transported through the sheet passageway 11 smoothly, the automatic sheet feeder 1 can further include a guiding element 14, disposed downstream of the first transporting assembly 22, for guiding the sheet S to the second transporting assembly 24.
In this embodiment, the automatic sheet feeder 1 is used in conjunction with a flatbed scanner 6 including a housing 62, a scan platen 64 and a scan module 66.
The scan platen 64 is mounted on the housing 62. The scan module 66 disposed in the housing 62 may move back and forth along a guiding rod 68 or may move to a predetermined position to continuously scan through the scan platen 64 and the opening 12 the sheet S and thus generate a corresponding image. The scan module 66 may comprise a charge-coupled device (CCD) sensor or a contact image sensor (CIS). In this embodiment, a CCD image sensor 664 is utilized in the scan module 66, which further includes a light source 661, a reflecting mirror 662 and a lens 663.
The scan apparatus with assemblies for transporting a sheet at different speeds according to this embodiment of the invention includes an automatic sheet feeder 1 and a flatbed scanner 6. The automatic sheet feeder 1 is disposed on the flatbed scanner 6. The automatic sheet feeder 1 and the flatbed scanner 6 are similar to those of the first embodiment, so detailed descriptions thereof will be omitted. The sheet transporting mechanism 20 disposed on the base 10 sequentially transports a first sheet S1 and a second sheet S2 through the sheet passageway 11. The automatic sheet feeder 1 comprises an image-processing area 12 which can be an opening or a transparent window, for example. The first transporting assembly 22 transports the first sheet S1 and the second sheet S2 sequentially to the image-processing area 12 at the first speed V1. The second transporting assembly 24 transports the first sheet S1 and the second sheet S2 sequentially away from the image-processing area 12 at the second speed V2.
In the flatbed scanner 6, the scan module 66 continuously scans the first sheet S1 and the second sheet S2 within the image-processing area 12, and generates a continuous image 90. The image-processing area 12 exposes a portion of the first sheet S1 and a portion of the second sheet S2, so through the image-processing area 12 the scan module 66 can scan the first sheet S1 and the second sheet S2. The continuous image 90 includes a first sheet image 91 corresponding to the first sheet S1, a second sheet image 92 corresponding to the second sheet S2 and a gap image 93 corresponding to a gap between the first sheet S1 and the second sheet S2.
The first roller 221 of the first transporting assembly 22 is disposed in the sheet passageway 11. The first roller 221 and the frictional element 222 separate the first sheet S1 from the second sheet S2 and sequentially transport the first sheet S1 and the second sheet S2 into the sheet passageway 11 and to the image-processing area 12.
The second roller 241 of the second transporting assembly 24, which is disposed in the sheet passageway 11, transports the first sheet S1 and the second sheet S2 sequentially away from the image-processing area 12 and out of the sheet passageway 11. The guiding element 14 guides the first sheet S1 and the second sheet S2 sequentially to the second transporting assembly 24.
In order to perform page separation that divides a continuous image into separate pages of images, the scan apparatus can further include an image-processing device 80, which is electrically connected to the scan module 66. The image-processing device 80 receives and processes the continuous image 90 according to the gap image 93 corresponding to the gap and thus divides the continuous image 90 into separate pages of images, that is, the first sheet image 91 and the second sheet image 92. The image-processing device 80 may be disposed in the flatbed scanner 6 or disposed in the automatic sheet feeder 1. The electrical connection includes, without limitation to, a wired or wireless connection.
In another way, an external image-processing device, for example, a personal computer, can be electrically connected to the scan apparatus and the scan apparatus outputs the continuous image 90 to the external image-processing device. In this case, the external image-processing device processes the continuous image 90 and divides the continuous image 90 into the first sheet image 91 and the second sheet image 92 according to the gap image 93.
According to the embodiments of the invention, multiple sheets can be successively scanned without using a sheet detector, and the gaps for page separation can be simultaneously generated. However, this does not imply that the sheet detector cannot be used. The gaps for page separation can be used in the subsequent image processing procedure so that the continuous image can be divided into separate pages of images. The function of current image-processing devices (e.g., a computer or a microprocessor) is getting more and more powerful, so that the scan apparatus with an image-processing device and the automatic sheet feeder of the invention can generate discrete images of the sheets like a conventional scan apparatus having sheet detectors. Therefore, the control circuit and the hardware elements of the scan apparatus can be effectively simplified, and the cost of the scan apparatus can be thus reduced.
While the invention has been described by way of examples and in terms of preferred embodiments, it is to be understood that the invention is not limited thereto. To the contrary, it is intended to cover various modifications. Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications.
| Number | Date | Country | Kind |
|---|---|---|---|
| 097119459 | May 2008 | TW | national |
