Abstract:
A document-ejecting/feeding mechanism is assembled inside an automatic document feeder, includes a driving device, gears, one-way clutches and rollers. After feeding action is canceled, the driving device is reversed and cooperates with the action of gears and one-way clutches, and at least one of rollers that near the paper-ejecting position is still rolled to the paper ejecting direction. Therefore, after the feeding action is canceled, the document will be still moved out from the feeder automatically and not tore.

Description:
FIELD OF THE INVENTION  
         [0001]    The present invention relates to a document-ejecting/feeding mechanism. The mechanism is used with an automatic document feeder of an image input/output device. The documents that are not ejected from the feeder can be released after canceling the document feeding function.  
         BACKGROUND OF THE INVENTION  
         [0002]    The automatic document feeder is usually cooperated with image input/output device and feeds one document at a time in the image input/output device. Taken an assembly of a scanner and an automatic document feeder as an example, each sheet of a pile of documents on the automatic document feeder can be fed to the scanning zone of the scanner to proceed scanning and obtaining images.  
           [0003]    In order to save time of the gaps during each feed, the documents are sent one by one in the feeder and a specific gap is defined between two adjacent documents so that there are two documents in the feeding path at a time.  
           [0004]    When the rear end of the first document is scanned, it is expected that the front end of the second document is located at the beginning position in the scanning zone. The first document is sent out from the feeder while the second document begins to be scanned.  
           [0005]    If the scanning action is canceled during the feeding of the documents (this canceling can be done by programmed software of computers), the documents in the scanning path are not yet scanned can be taken out by opening the cover of the feeder.  
           [0006]    However, the document that has been completely scanned is remained in the feeding path and stocked between rollers. The document may be pulled out by rotating the rollers or pulling the document directly. The rollers are engaged with gears which transmit power from the motor, so the pulling of the document rotates the motor. The damping force of the motor is magnified by the reduction gears so that the document could be torn when being pulled.  
           [0007]    When a user wants to scan a pile of documents, either he/she can use a scanner to scan the whole pile of documents by using an automatic document feeder at a time, or he/she can use a scanner to scan one document by using the feeder to send one document at a time.  
           [0008]    The inherent problems of continuous feeding of the automatic document feeder have been mentioned hereinbefore. It will depict the inconvenience when using the automatic document feeder to send the document one by one hereinafter.  
           [0009]    Due to the fact that two documents are located in the feeding path at the same time, the first document cannot be released even if it is completely scanned, and this will blockade the process of the scanning action. Besides, the users perhaps thought that the scanner does not work in order. Besides, when the first document after being scanned has to be taken to another place immediately, the first document still in the scanner and cannot be easily taken out. The conventional feeders cannot provide a solution for these problems.  
         SUMMARY OF THE INVENTION  
         [0010]    The primary object of the present invention is to provide a document-ejecting/feeding mechanism, and in particular to automatically send the document out from the feeder when the feeding order is canceled.  
           [0011]    The purpose is achieved by reversing the driving device cooperated with gears and one-way clutches to let at least one roller keep rolling to send the document out. Therefore, even if the feeding order is canceled, the document can be sent out.  
           [0012]    The present invention will become more obvious from the following description when taken in connection with the accompanying drawings which show, for purposes of illustration only, preferred embodiments in accordance with the present invention. 
       
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0013]    [0013]FIG. 1 is a cross sectional view to show the automatic document feeder of the present invention.  
         [0014]    [0014]FIG. 2 is a perspective view to show the ejecting/feeding mechanism of the feeder of the present invention.  
         [0015]    [0015]FIG. 3 is a side view to show the ejecting/feeding mechanism of the feeder of the present invention.  
         [0016]    [0016]FIG. 4 is another side view to show the ejecting/feeding mechanism of the feeder of the present invention.  
         [0017]    [0017]FIG. 5 shows the feed of documents of the present invention.  
         [0018]    [0018]FIG. 6 shows the ejection of documents of the present invention.  
         [0019]    [0019]FIG. 7 shows the first status of the concise version of the present invention.  
         [0020]    [0020]FIG. 8 shows the second status of the concise version of the present invention.  
         [0021]    [0021]FIG. 9 shows the third status of the concise version of the present invention. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0022]    [0022]FIG. 1 shows the automatic document feeder which has a body  10  with a document-ejecting/feeding mechanism  20  received therein.  
         [0023]    The body  10  has an input end  11  and an output end  12 , wherein a U-shaped passage  13  is connected between the input end  11  and the output end  12 . A plate  14  is located on a side of the input end  11  so that documents (not shown) are put on the plate  14 . A scanning zone “S” is defined as the zone for scanning the document.  
         [0024]    [0024]FIG. 2 shows the document-ejecting/feeding mechanism  20  which has a plurality of rollers  21 ,  22 ,  23 ,  24 , a set of driving device  31 , a plurality of one-way clutches  41 ,  42 .  
         [0025]    The feeding roller  21  is mounted on a shaft  25  whose first end  251  and second end  252  are respectively connected with the one-way clutches  41 ,  42 . The one-way clutch  42  on the second end  252  has a pulley  253  connected thereto.  
         [0026]    In this embodiment, the number of ejecting rollers  24  is two (the number also may be one or more than two) and are mounted on a shaft  28  whose first end  281  and second end  282  are respectively connected to a one-way clutch  41  and a pulley  283 . The one-way clutch  41  has a gear  43  connected thereto and is installed in a direction opposite to the direction of the one-way clutch  42 .  
         [0027]    In this embodiment, the number of assist rollers  22  is two (the number may be one or more than two) and the rollers  22  are mounted on a shaft  26  which has a first end  261  and a second end  262  which is connected to a pulley  264 . The assist rollers  22  are located between the feeding roller  21  and the ejecting roller  24 .  
         [0028]    The number of assist rollers  23  is two and the two assist rollers  23  are mounted on a shaft  27  which has a first end  271  and second end  272  which is connected to a pulley  273 . The assist rollers  23  are located between the assist rollers  22  and the ejecting rollers  24 .  
         [0029]    The driving device  31  includes a motor (not shown), a plurality of transmission pulleys  32 ,  33 ,  34 , and  35 , and a plurality of belts  36 ,  37 ,  38  and  39 .  
         [0030]    The output shaft (not shown) of the motor is connected to the transmission pulley  32  which is connected to another transmission pulley  33  by a belt  36 . Another transmission pulley  331  is co-axially connected to the transmission pulley  33 .  
         [0031]    Referring to FIGS. 2 and 3, the transmission pulleys  331 ,  34 ,  35  and the one-way clutch  41  which is also a transmission pulley on the first end  251  of the shaft  25  form four points of a quadrilateral with the belt  37  winding around the four points.  
         [0032]    It is to be noted that the transmission pulley  34  is an idle gear for changing the transmission direction of the output from the belt  37 . A gear  341  co-axially connected to a side of the transmission pulley  34  is engaged with the gear  43  on a side of the one-way clutch  41 .  
         [0033]    The transmission pulley  35  has a co-axially connected gear  351  which is engaged with the gear  53  on the shaft  52  of the feeding roller  51 .  
         [0034]    Referring to FIGS. 2 and 4, the belt  38  is wound around the pulleys  253  and  264 , and the belt  39  is wound around the one-way clutch  42  on the second end of the shaft  25  and the pulleys  273 ,  283 .  
         [0035]    As shown in FIG. 1, the ejecting/feeding mechanism  20  is located between the input end  11  and the output end  12  of the body  10 . The feeding roller  21  is located close to the input end  11 , and the ejecting roller  24  is located close to the output end  12 . Each of the feeding roller  21 , the assist rollers  22 ,  23  and the ejecting roller  24  has a part located in the passage  13 .  
         [0036]    [0036]FIG. 5 shows the feeding action, wherein the scanned document is released from the scanning zone and the next document has not yet entered in the scanning zone “S”. When the motor (not shown) rotates clockwise, the transmission pulleys  331 ,  34 ,  35  and the one-way clutch  41  are rotated clockwise. The gear  351  connected with the transmission pulley  35  is engaged with the gear  53  so as to drive the feeding roller  51  to feed the document  61  into the mechanism  20  via the passage  13  which is not shown.  
         [0037]    The feeding roller  21  and the assist roller  22  are connected by the belt  38  so that the feeding roller  21  and the assist roller  22  have the same rotational direction.  
         [0038]    The feeding roller  21  and the assist roller  23  are connected by the belt  39  so that the feeding roller  21  and the assist roller  23  have the same rotational direction.  
         [0039]    It is to be noted that the ejecting roller  24  includes a one-way clutch  41  on an end thereof and the gear  43  cooperated with the one-way clutch  41  is engaged with the gear  341  mounted to the transmission pulley  34 . When the gear  341  is rotated clockwise, the gear  43  rotates in opposite direction so that the one-way clutch  41  is in idle status.  
         [0040]    The pulley  283  on the other end of the ejecting roller  24  is connected to the feeding roller  21  by the pulley  39 , so the ejecting roller  24  is rotated in the same direction as the feeding roller  21 .  
         [0041]    The documents  61  can be released after being transported by the same rotational direction of the feeding roller  21 , the assist rollers  22 ,  23  and the ejecting roller  24 .  
         [0042]    [0042]FIG. 6 shows the ejection of document. When the feeding order is canceled which can be achieved by software, the motor (not shown) rotates in reverse (counterclockwise). The transmission pulleys  331 ,  34 ,  35  and the one-way clutch  41  are rotated counterclockwise.  
         [0043]    Because the one-way clutch (not shown) connected to the shaft  52  of the ejecting roller  51  is not used, the gears  351 ,  53  will not let the feeding roller  51  feed the documents in the document-ejecting/feeding mechanism  20 .  
         [0044]    Because each of two ends of the feeding roller  21  includes a one-way clutch  41 / 42  which is in idle status, the feeding roller  21  does not rotate.  
         [0045]    The assist roller  22  and the feeding roller  21  is driven by the belt  38  and the assist roller  22  is not connected with other rollers so that when the feeding roller  21  is in idle status, the assist roller  22  does not rotate.  
         [0046]    The gear  341  of the transmission pulley  34  is engaged with the gear  43  of the ejecting roller  24 , so that when the gear  341  is rotated in counterclockwise, the gear  43  is rotated clockwise. The one-way clutch  41  is operated to let the ejecting roller  24  rotate clockwise.  
         [0047]    Although the ejecting roller  24 , the assist roller  23  and the feeding roller  21  are connected by the belt  39 , the one-way clutch  42  on the feeding roller  21  is in idle status and the assist roller  23  is driven by the ejecting roller  24  only. So, the feeding roller  21  is remained in still and the assist roller  23  and the ejecting roller  24  are rotated clockwise. By this way, the document  61  located at the bottom of the assist roller  23  and the ejecting roller  24  may be automatically ejected.  
         [0048]    Therefore, when ejecting the document, the motor rotates counterclockwise and the roller on the left side of the scanning zone “S” keeps on rotating in the original direction, and the roller on the right side of the scanning zone “S” is remained in still. The document that escaped from the scanning zone “S” is ejected by the document-ejecting/feeding mechanism  20 .  
         [0049]    FIGS.  7  to  9  show a concise version of the present invention, which needs only two feeding rollers, rather than four feeding rollers. In comparison with FIG. 2, the assist rollers and related parts are saved.  
         [0050]    Referring to FIG. 7, the motor is rotated clockwise to drive the pulley  32  counterclockwise. The belt  36 , the transmission pulleys  33 ,  331 , the belt  37 , the transmission pulley  34 , the gear  341 , the transmission pulley  35 , and the one-way clutch  41  are rotated counterclockwise. The one-way clutch  41  on the first end  251  of the shaft  25  drives the shaft  25  and the feeding roller  21 . The shaft  25  also drives the one-way clutch  42  on the second end  252  of the shaft  25 , belt  39 , the pulley  283  on the second end  282  of the shaft  28 , the shaft  28  and the final ejecting roller  24  in counterclockwise. On the hand, the gear  341  drives the gear  43  on the first end  281  of the shaft  28  and the one-way clutch  41  clockwise. The one-way clutch  41  is not activated so as to allow the directions of the shaft  28  and the gear  43  to be different. By this way, the feeding may work normally.  
         [0051]    Referring to FIG. 8, when ejecting the document, the motor is rotated in reverse and the pulley  32  rotates clockwise. The belt  36 , the transmission pulleys  33 ,  331 , the belt  37 , the transmission pulley  34 ,-the gear  341 , the transmission pulley  35  and the one-way clutch  41  are rotated clockwise. The one-way clutch  41  does not function so that the shaft  25  and the feeding roller  21  are not rotated. On the other hand, the gear  341  drives the gear  43  and the one-way clutch  41  counterclockwise. The one-way clutch  41  drives the shaft  28  and the final ejecting roller  24  counterclockwise. The shaft  28  drives the pulley  283 , the belt  39  and the one-way clutch  42  to rotate counterclockwise. At this presence, the one-way clutch  42  is not activated so that the shaft  25  is remained in still.  
         [0052]    Therefore, the final ejecting roller  24  rotates clockwise whichever direction the motor is rotated.  
         [0053]    As shown in FIG. 9, as long as the feeding roller  21  and the ejecting roller  24  are located on two sides of the scanning zone “S”, the above mentioned functions of the ejecting/feeding function can be achieved.  
         [0054]    The roller located close to the output end is remained in its original rotational direction to eject the document by reversing the motor and the cooperation of the gear and the one-way clutch even if the feeding order is canceled during scanning process. The last document can be ejected without the need of pulling manually.  
         [0055]    Furthermore, by using the feeder of the present invention, the user may scan one document at a time and no document will be trapped in the feeder.  
         [0056]    While we have shown and described the embodiments in accordance with the present invention, it should be clear to those skilled in the art that further embodiments may be made without departing from the scope of the present invention.