Abstract:
A document holding fixture for a vertical optical scanner. The fixture has a main body, a transparent panel, four linking bars, a document cover panel, and a document backing plate. The document holding fixture uses a simple four linking bar system to maintain a constant parallelism between the document cover panel and the surface of the transparent panel. Weight of the document cover panel provides necessary pressure to press a scan document firmly onto the glass surface of the transparent panel. To facilitate single hand document insertion, a stationing device is used to freeze the document cover panel when the panel reaches a horizontal position.

Description:
BACKGROUND OF THE INVENTION  
       [0001]     1. Field of Invention  
         [0002]     The present invention relates to a document holding fixture. More particularly, the present invention relates to the document holding fixture for a vertical optical scanner.  
         [0003]     2. Description of Related Art  
         [0004]     A conventional optical scanner is shown in  FIG. 1 . The optical scanner has a main body  100  and an upper lid  200 . To scan a document  400 , the document  400  is placed flat on a horizontal transparent panel  300 . The upper lid  200  is lowered onto the document  400  before the document is scanned. However, this type of scanner needs to occupy a relatively large desk area and thus reduces workspace. Furthermore, a horizontal optical scanner is limited by document size.  
         [0005]     An effective means of reducing area occupancy and increasing workspace is to design a vertical type of optical scanner. However, one major problem for producing a vertical optical scanner is the provision of an effective document holding fixture.  
       SUMMARY OF THE INVENTION  
       [0006]     Accordingly, one object of the present invention is to provide a document holding fixture that utilizes gravity and a simple four-link mechanism to grip and hold a document such that the document is attached firmly onto a transparent panel.  
         [0007]     To achieve these and other advantages and in accordance with the purpose of the invention, as embodied and broadly described herein, the invention provides a document holding fixture for a vertical optical scanner. The vertical optical scanner at least includes a main body and a transparent panel for document placement. The main body has two open slots, one on each side of the transparent panel, so that the transparent panel is held in a vertical position relative to the ground. The document holding fixture includes four linking bars, a cover panel and a backing plate. The four linking bars are parallel to each other. Each linking bar has a first end and a second end. The first end of every pair of linking bars extends into an open slot on the main body and is respectively connected by hinges. The cover panel faces the transparent panel. The cover panel always remains parallel to the transparent panel as the cover panel is moved. The second end of every pair of linking bars is connected to the respective sides of the cover panel by hinges. The backing plate is mounted on the main body at the lower ledge of the transparent panel. The backing plate serves as a support and an alignment base for the document placed next to the transparent panel.  
         [0008]     This invention also provides a vertical optical scanner. The vertical optical scanner has a transparent panel, a main body, a scanning module, a transmission device, an electric motor, four linking bars, a cover panel and a backing plate. The transparent panel is perpendicular to the ground and capable of scanning a document. The main body has an open slot on each side of the transparent panel. The scanning module is installed inside the main body. The transmission device inside the main body connects with and drives the scanning module during a scanning operation. The electric motor inside the main body connects with and drives the transmission device. The four linking bars are parallel to each other. Each linking bar has a first end and a second end. The first end of every pair of linking bars extends into an open slot on the main body and is respectively connected by hinges. The cover panel faces the transparent panel. The cover panel always remains parallel to the transparent panel as the cover panel is moved. The second end of every pair of linking bars is connected to the respective sides of the cover panel by hinges. The backing plate is mounted on the main body at the lower ledge of the transparent panel. The backing plate serves as a support and an alignment base for the document placed next to the transparent panel.  
         [0009]     One major aspect of this invention is the reduction of floor space due to the deployment of a vertical optical scanner.  
         [0010]     A second aspect of this invention is the selection of a simple four linkage parallel mechanism. This mechanism serves to maintain a constant parallelism between the document cover panel and the transparent panel. A scan document is pressed firmly onto the glass surface of the transparent panel by the weight of the document cover.  
         [0011]     A third aspect of this invention is the provision of a backing plate to serve as a support and an alignment base for the scan document so that the document is prevented from dropping to the floor.  
         [0012]     A fourth aspect of this invention is the provision of a stationing device for maintaining a constant horizontal position that facilitates single hand insertion of a scan document.  
         [0013]     It is to be understood that both the foregoing general description and the following detailed description are exemplary, and are intended to provide further explanation of the invention as claimed. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0014]     The accompanying drawings are included to provide a further understanding of the invention, and are incorporated in and constitute a part of this specification. The drawings illustrate embodiments of the invention and, together with the description, serve to explain the principles of the invention. In the drawings,  
         [0015]      FIG. 1  is a perspective view of a conventional horizontal optical scanner;  
         [0016]      FIG. 2  is a perspective view of a vertical optical scanner according to this invention,  
         [0017]      FIG. 3  is an exploded view of all the major components constituting the vertical optical scanner according to this invention;  
         [0018]      FIG. 4  is a side view showing a lowered document cover panel of the vertical optical scanner according to this invention;  
         [0019]      FIG. 5  is a side view showing a lifted document cover panel of the vertical optical scanner according to this invention;  
         [0020]      FIGS. 6   a  and  6   b  are sketches showing two cam positions for stationing the document cover panel according to this invention,  
         [0021]      FIG. 7  is a sketch showing an additional stationing device beside the guiding slot opening of the document cover panel; and  
         [0022]      FIG. 8  is a side view showing a spring-loaded lever system for locking the document cover panel according to this invention. 
     
    
     DESCRIPTION OF THE PREFERRED EMBODIMENTS  
       [0023]     Reference will now be made in detail to the present preferred embodiments of the invention, examples of which are illustrated in the accompanying drawings. Wherever possible, the same reference numbers are used in the drawings and the description to refer to the same or like parts.  
         [0024]      FIG. 2  is a perspective view of a vertical optical scanner according to this invention.  FIG. 3  is an exploded view of all the major components constituting the vertical optical scanner according to this invention. As shown in  FIGS. 2 and 3 , the vertical optical scanner has a main body  1100 . A transparent panel  1300  is on one side of the main body  1100  perpendicular to the floor. The main body  1100  has a guiding slot  1500  on each side. A pair of linking bars  1600  passes through each guiding slot  1500  and fastens to the main body  1100 . All four linking bars  1600  are parallel to each other. Each linking bar  1600  is free to move vertically through rotation relative to the point of attachment inside the main body  1100 .  
         [0025]     The other ends of the four linking bars are attached to the respective sides of a document cover panel  1200 . Each linking bar  1600  is free to move vertically through rotation relative to the point of attachment at the document cover panel  1200 . Since the four linking bars  1600  are mutually parallel, constant parallelism between the document cover panel  1200  and the transparent panel  1300  can be maintained. Through simultaneous vertical movement of all four linking bars  1600  about their respective pivotal attachment points at the main body  1100  and the document cover panel  1200 , the panel  1200  is free to move towards or away from the transparent panel  1300 . There is a handle  1210  on the exterior-facing surface of the document cover panel  1200  for lifting up the cover panel  1200 .  
         [0026]      FIG. 4  is a side view showing a lowered document cover panel of the vertical optical scanner according to this invention. Before conducting a scanning operation, the document, a force is applied to the handle  1210  to lift the document cover panel  1200 . When the document cover panel  1200  is lifted up to such an extent that the four linking bars  160  are almost horizontal, a spring-loaded lock  1700  mounted on the main body  110  and located next to a pair of linking bars  1600  is employed to station the panel  1200 . The spring-loaded lock  1700  has an internal spring  1710  (as shown in  FIG. 3 ) that pushes the lock  1700  outward and latches the linking bars  1600  at a supporting surface  1730  (as shown in  FIG. 3 ). Through this mechanism, the four linking bars  1600  are supported and the document cover panel  1200  is prevented from falling.  FIG. 5  is a side view showing a lifted document cover panel of the vertical optical scanner according to this invention. At this point, no force needs to be applied to station the document cover panel  1200 . A scan document  1400  may easily slip into the space between the transparent panel  1300  and the document cover panel  1200 . Furthermore, there is a backing plate  1800  attached to the lower ledge of the main body  1200  for supporting the scan document  1400  and serving as an alignment base for the document  1400 .  
         [0027]     After proper positioning of the scan document  1400 , the spring-loaded lock  1700  is depressed forcing the linking bars  1600  to dislocate from the supporting surface  1730  and fall into a groove  1720  (as shown in  FIG. 3 ). Due to force of gravity, the document cover panel  1200  drops down bringing the cover panel  1200  back to the previous tight engagement position with the transparent panel  1300  (as shown in  FIG. 4 ). Once the scan document  1400  is firmly pressed against the transparent panel  1300 , scanning may begin. To initiate a scanning operation, an electric motor inside the main body  1100  drives a transmission device that carries a scanning module (not shown) to perform necessary scanning of the document  1400  on the transparent panel  1300 .  
         [0028]     The aforementioned holding device is not limited to the spring-loaded lock  1700 . A cam system using a cam  1900  such as the one shown in  FIGS. 6   a  and  6   b  may be used. Alternatively, a supporting groove  1510  sticking into the guiding slot opening such as the one in  FIG. 7  or a spring-lever fastening lock  200  having a structure shown in  FIG. 8  may be used instead. In fact, any methods or devices capable of stationing the document cover panel  1200  in a horizontal position can be employed.  
         [0029]      FIGS. 6   a  and  6   b  are sketches showing two cam positions for stationing the document cover panel according to this invention. As shown in  FIGS. 6   a  and  6   b , a cam  1900  and a rubber roller  1910  system is mounted at the junction between at least one linking bar  1600  and the main body  1100 . When the document cover panel  1200  is lifted from a position shown in  FIG. 6   a  to a position shown in  FIG. 6   b , the cam  1900  and the roller  1910  are pressed together so that the document cover panel  1200  is held in a horizontal position.  FIG. 7  is a sketch showing an additional stationing device beside the guiding slot opening of the document cover panel. As shown in  FIG. 7 , a supporting groove  1510  is added to the guiding slot opening  1500 . When the document cover panel  1200  is lifted to a horizontal position, the linking bars  1600  are moved into the supporting grooves  1510  so that the document cover panel  1200  is held in the horizontal position.  FIG. 8  is a side view showing a spring-loaded lever system for locking the document cover panel according to this invention. As shown in  FIG. 8 , a spring-loaded lever lock  2000  is attached to the junction between the main body  1100  and at least one of the linking bar  1600 . The spring-loaded level lock has an internal spring  2010  and a round rod  2020 . The spring  2010  pushes against the round rod  2020  so that the movement of the linking bar  1600  from the solid line position to the centerline position is stable. Hence, the document cover panel  1200  can remain in a horizontal position.  
         [0030]     In conclusion, major advantages of this invention include: 
    1. Floor space is reduced because the optical scanner is erected vertically relative to the floor. Furthermore, volume of the optical scanner is not limited by size of the document.     2. A simple four linkage parallel mechanism is used. This mechanism maintains a constant parallelism between the document cover panel and the transparent panel. Weight of the document cover also presses a scan document firmly onto the glass surface of the transparent panel.     3. The handle on the backing plate permits easy lifting of the document cover panel.     4. A stationing device for holding the document cover panel in a horizontal position facilitates single hand insertion of a scan document.    
 
         [0035]     It will be apparent to those skilled in the art that various modifications and variations can be made to the structure of the present invention without departing from the scope or spirit of the invention. In view of the foregoing, it is intended that the present invention cover modifications and variations of this invention provided they fall within the scope of the following claims and their equivalents.