Abstract:
A scanner and a scanning method having adjustable length of turn region are disclosed. The scanner comprises a first fixed element having an entry for a paper-in end; a U-turn element; and a second fixed element having an exit for a paper-out end. In addition, the scanner further comprises at least one first movable element located between the exit of the first fixed element and the entry of the U-turn element; and at least one second movable element located between the exit of the U-turn element and the entry of the second fixed element. Moreover, the scanning method comprises: firstly inputting the length of the document into the scanner; comparing the length of the document with the length of turn region; adjusting the length of turn region according to the comparison result; scanning the document.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to a scanner and a scanning method, and more particularly, to a scanner and a scanning method having adjustable length of turn region.  
         BACKGROUND OF THE INVENTION  
         [0002]    Recently, workstations and personal computers, etc. have been developed to have high performance and be able to proceed with rapid processing of full-color image. Accompanying with the development, scanners used to convert photos, slides, or manuscripts to digital data have become more and more popular.  
           [0003]    Scanners can be classified into types including flat bed scanner and drum scanner, etc. The master copy stand of the flat bed scanner is a flat plane and the flat bed scanner adopts a charge coupled device (CCD) to be a photoreceptor. The master copy stand of the drum scanner is a transparent acrylic drum and the drum scanner adopts a photomultiplier (PMT) to be a photoreceptor.  
           [0004]    Accompanying with the development of the CCD technique, almost all of the scanners currently in the market are color flat bed scanners. The flat bed scanner is usually cheaper than the traditional drum scanner, but both can scan in similar quality.  
           [0005]    Please refer to FIG. 1 showing the side view of a turn region of the conventional scanner. The turn region  10  in FIG. 1 is used for double-side scanning a document (not shown). Before the document enters the turn region  10  in the paper-in direction as shown by an arrow  20 , the scanning of the first side (the side facing downward in FIG. 1) of the document can be done by the action of a light source (not shown) and an image-reading device  50 . Then, the document enters the upper part of the turn region  10  in the paper-in direction as shown by an arrow  20 . Afterwards, the document can turn smoothly and go forward continuously by the assistance of a roller  30 , and then enters the lower part of the turn region  10 . At this time, the aforementioned first side of the document faces upward naturally, and the second side of the document faces downward naturally. Then, the document leaves the turn region  10  in the paper-out direction as shown by an arrow  40 . After the document leaves the turn region  10 , the scanning of the second side of the document facing downward can be done by the action of the light source and the image-reading device  50 . Therefore, the document can proceed with double-side scanning smoothly by the turn region  10 .  
           [0006]    Even though the document can be double-side scanned smoothly via the turn region  10  as shown in FIG. 1, the following disadvantages still exist. Since every scanner has its own maximum size of the document allowed to be scanned (such as A4), hence the length  60  of the turn region  10  needs to be designed according to this maximum size. Therefore, if the scanner is used to double-side scan the document having the maximum size, no problem will happen certainly. However, if the scanner is used to double-side scan a document having a size (such as A5) smaller than the maximum size, the smaller document still has to pass the same path and consume the same time to complete the double-side scanning, because the length  60  of every conventional double-side scanner cannot be changed. In fact, the smaller the size of the document is, the more the time is wasted. Therefore, it is necessary to find a solution.  
         SUMMARY OF THE INVENTION  
         [0007]    Just as described above, the length of turn region of the conventional double-side scanner cannot be changed, so that there is a disadvantage of wasting time during scanning the document having a smaller size. Therefore, an objective of the present invention is to provide a scanner and a scanning method having adjustable length of turn region, thereby adjusting the length of turn region according to different paper lengths.  
           [0008]    Another objective of the present invention is to provide a scanner and a scanning method having adjustable length of turn region, thereby shortening the scanning time.  
           [0009]    According to the aforementioned objectives of the present invention, the present invention provides a scanner having an adjustable length of turn region suitable for use in double-side scanning a document, wherein when the scanner is used to scan the document having a maximum size, the turn region has a longest path, and the scanner comprises: a first fixed element, wherein an entry of the first fixed element is a paper-in end; a U-turn element, wherein two hooks of an entry of the U-turn element are engaged with two hooks located on an exit of the first fixed element respectively; and a second fixed element, wherein two hooks of an entry of the second fixed element are engaged with two hooks located on an exit of the U-turn element respectively, and an exit of the second fixed element is a paper-out end, wherein when the scanner is used to scan the document having a smaller size, the U-turn element moves towards the entry of the first fixed element and the exit of the second fixed element, thereby enabling the document to pass a shorter path. In addition, the scanner having the adjustable length of turn region of the present invention further comprises a roller located on an inner side of the U-turn element, thereby enabling the document to turn smoothly and go forward continuously in the U-turn element. Moreover, the scanner having the adjustable length of turn region of the present invention further comprises at least one first movable element, wherein two hooks located on an entry of each of the at least one first movable element are engaged with two hooks located on an exit of another of the at least one first movable element or with the two hooks located on the exit of the first fixed element respectively, and two hooks of an exit of each of the at least one first movable element are engaged with two hooks located on an entry of another of the at least one first movable element or with the two hooks located on the entry of the U-turn element respectively; and at least one second movable element, wherein two hooks located on an entry of each of the at least one second movable element are engaged with two hooks located on an exit of another of the at least one second movable element or with the two hooks located on the exit of the U-turn element respectively, and two hooks located on an exit of each of the at least one second movable element are engaged with two hooks located on an entry of another of the at least one second movable element or with the two hooks located on the entry of the second fixed element respectively. Further, the scanner having the adjustable length of turn region of the present invention further comprises an image-reading device, wherein before the document enters the first fixed element, the image-reading device is used to scan one side of the document; and after the document leaves the second fixed element, the image-reading device is used to scan the other side of the document.  
           [0010]    According to the aforementioned objectives of the present invention, the present invention further provides a scanning method having an adjustable length of turn region suitable for double-side scanning a document, wherein when the scanner is used to scan the document having a maximum size, the turn region has a longest path, and the scanning method comprises the following steps: firstly, inputting a length of the document into the scanner; then, comparing the length of the document with the length of the turn region; then, adjusting the length of the turn region according to a result from the comparing step; and afterwards, scanning the document. Furthermore, the aforementioned inputting step can be achieved via a computer or a user interface (UI) of the scanner. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0011]    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:  
         [0012]    [0012]FIG. 1 is a diagram showing the side view of the turn region of the conventional scanner;  
         [0013]    [0013]FIG. 2 is a diagram showing the side view of the turn region of the scanner according to an embodiment of the present invention, wherein the turn region has been extended to the maximum length;  
         [0014]    [0014]FIG. 3 is a diagram showing the side view of the turn region of the scanner according to an embodiment of the present invention, wherein the turn region has been shortened to the minimum length;  
         [0015]    [0015]FIG. 4 is a diagram showing the side view of the turn region of the scanner according to another embodiment of the present invention; and  
         [0016]    [0016]FIG. 5 is a flow chart showing the scanning method having adjustable length of turn region according to an embodiment of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0017]    The present invention relates to a scanner and a scanning method having adjustable length of turn region. Please refer to FIG. 2 showing the side view of the turn region of the scanner according to an embodiment of the present invention, wherein the turn region has been extended to the maximum length. A turn region  110  as shown in FIG. 2 is composed of a fixed element  170 , a fixed element  174 , a U-turn element  178 , movable elements  171  to  173 , and movable elements  175  to  177 , etc. In the upper part of the turn region  110 , two hooks  201  of the fixed element  170  are engaged with two hooks  202  of the movable element  171 ; two hooks  203  of the movable element  171  are engaged with two hooks  204  of the movable element  172 ; two hooks  205  of the movable element  172  are engaged with two hooks  206  of the movable element  173 ; and two hooks  207  of the movable element  173  are engaged with two hooks  208  of the U-turn element  178 . At the same reason, in the lower part of the turn region  110 , two hooks  211  of the fixed element  174  are engaged with two hooks  212  of the movable element  175 ; two hooks  213  of the movable element  175  are engaged with two hooks  214  of the movable element  176 ; two hooks  215  of the movable element  176  are engaged with two hooks  216  of the movable element  177 ; and two hooks  217  of the movable element  177  are engaged with two hooks  218  of the U-turn element  178 . In the aforementioned elements of the turn region  110 , only the fixed element  170  and the fixed element  174  are fixed, and other elements are movable along an appropriate horizontal direction. Since all elements are engaged with each other mutually by hooks, hence a length  160  of the turn region  110  can be shortened appropriately and the condition that the elements separated with each other will not happen.  
         [0018]    Before the document enters the turn region  110  in the paper-in direction as shown by an arrow  120 , the scanning of the first side (the side facing downward in FIG. 2) of the document can be done by the action of a light source (not shown) and an image-reading device  150 . Then, the document enters the upper part of the turn region  110  in the paper-in direction as shown by an arrow  120 . Afterwards, the document can turn smoothly and goes forward continuously by the assistance of a roller  130 , and then enters the lower part of the turn region  110 . At this time, the aforementioned first side of the document faces upward naturally, and the second side of the document faces downward naturally. Then, the document leaves the turn region  110  in the paper-out direction as shown by an arrow  140 . After the document leaves the turn region  110 , the scanning of the second side of the document facing downward can be done by the action of the light source and the image-reading device  150 . Therefore, the document can proceed with double-side scanning smoothly by the turn region  110 .  
         [0019]    The aforementioned turn region  110  as shown in FIG. 2 has been extended to the length  160  that is longest. Therefore, the turn region  110  having the length  160  can be suitable for use in double-side scanning of the document having the maximum size. When the size of the document desired to be double-side scanned is smaller than the maximum size allowed, the length  160  can be shortened appropriately to save the scanning time. The extreme condition is that the length  160  of the turn region  110  can be shortened to a length  162  as shown in FIG. 3, wherein the turn region  110  having the length  162  can be suitable for use in double-side scanning of the document having the minimum size. In addition, the process for changing the state of the turn region  110  as shown in FIG. 2 to that as shown in FIG. 3 is desired as the following.  
         [0020]    Firstly, the U-turn element  178  moves in the direction as shown by the arrow  140  until the hooks  208  contact the hooks  206 , and the hooks  210  contact the hooks  217 . Then, the U-turn element  178 , the movable element  173 , and the movable element  177  move together in the direction as shown by the arrow  140  until the hooks  206  contact the hooks  204 , and the hooks  217  contact the hooks  215 . Then, the U-turn element  178 , the movable element  173 , the movable element  177 , the movable element  172 , and the movable element  176  move together in the direction as shown by the arrow  140  until the hooks  204  contact the hooks  202 , and the hooks  215  contact the hooks  213 . Then, the U-turn element  178 , the movable element  173 , the movable element  177 , the movable element  172 , the movable element  176 , the movable element  171 , and the movable element  175  move together in the direction as shown by the arrow  140  until the hooks  202  contact the hooks  200 , and the hooks  213  contact the hooks  211 . At this time, the state of the turn region  110  is just as shown in FIG. 3.  
         [0021]    Furthermore, the aforementioned description as shown in FIG. 2 is only an embodiment of the scanner of the present invention. In fact, the number of movable elements (such as the movable elements  171  to  173  and the movable elements  175  to  177 ) can be designed according to the actual specification of the scanner. That is, the number of movable elements can be more or less than that of the movable elements in the present embodiments, or can be even zero. If movable elements do not exist, the hooks  208  of the U-turn elements  178  will be engaged with the hooks  201  of the fixed element  170 , the hooks  218  of the U-turn elements  178  will be engaged with the hooks  211  of the fixed element  174 , and the objective of shortening the length  160  of the turn region  110  can be achieved similarly.  
         [0022]    Moreover, the aforementioned the movable element  173 , the movable element  177 , the movable element  172 , the movable element  176 , the movable element  171 , and the movable element  175  can be moved by the external force pushing or pulling the U-turn element  178 . Further, the user can apply the external force on the U-turn element  178  directly. Or, the external force can be exerted automatically on the U-turn element  178  under the cooperation of a worm gear  180 , a gear  190 , and a motor (not shown) as shown in FIG. 4. One end of the worm gear  180  is connected to with the U-turn element  178 , and the other end of the worm gear  180  is a free end. The gear  190  makes the worm gear  180  to proceed with translation by rotation, thereby driving the U-turn element  178  to move  
         [0023]    As described above, when the external force exerted on the U-turn element  178  is generated automatically under the cooperation of the worm gear  180  and the gear  190 , etc., the present invention further provides a scanning method comprising the steps as shown in the flow chart of FIG. 5. Firstly, as shown by a step  310 , the length of the document is inputted to the scanner, wherein the step  310  can be achieved via a computer or a UI of the scanner. Then, as shown by a step  320 , the length of the document and the length of the turn area are compared in the scanner. Then, as shown by a step  330 , the length of the turn area is adjusted according to the result of the step  320 . That is, if the length of the turn region is greater than the length needed, the length of the turn region can be shortened automatically; if the length of the turn region equals to the length needed, there is no need to adjust the length of the turn region; or, if the length of the turn region is smaller than the length needed, the length of the turn region can be lengthened automatically. Afterwards, as shown by a step  340 , the document is scanned.  
         [0024]    To sum up, an advantage of the present invention is to provide a scanner and a scanning method having adjustable length of turn region, thereby adjusting the length of turn region according different paper lengths.  
         [0025]    Another advantage of the present invention is to provide a scanner and a scanning method having adjustable length of turn region, thereby shortening the scanning time.  
         [0026]    As is understood by a person skilled in the art, the foregoing preferred embodiments of the present invention are illustrations of the present invention rather than limitations of the present invention. It is intended to cover various modifications and similar arrangements comprised within the spirit and scope of the appended claims, the scope of which should be accorded the broadest interpretation so as to encompass all such modifications and similar structure.