Patent Publication Number: US-RE41322-E

Title: Structure for protecting and guiding flat cable of traveling module

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to a protective structure for a flat cable, and more particularly to a structure for protecting and guiding a flat cable connected between a traveling module and a cover arranged in an image scanning device. 
     2. Description of the Prior Art 
     In various kinds of optical devices or electric appliances (such as image scanner, photo copier, test instrument, etc.), there is often equipped with traveling modules therein. For example, as shown in  FIG. 1 , it is a perspective view of a conventional image scanning device, showing that a focusing lens  2 , a protective cover  3 , a pair of corresponding guide rods  4 a,  4 b, and two movable traveling modules  5 a,  5 b are arranged in the housing  1  of the conventional optical image scanner. 
     The guide rods  4 a,  4 b serve as a guiding mechanism for guiding two traveling modules  5 a,  5 b. The first traveling module  5 a carries a light tube as a light source for the image scanning device, while the second traveling module  5 b carries a set of reflection mirrors for reflecting the light projected from the light source. 
     During scanning, a document to be scanned is placed on a document positioning plate of the scanner. It is known that the document positioning plate is a plane surface made of for example glass or other light transmittable, substantially rigid material, for supporting a document to be scanned. The light tube of the first traveling module  5 a projects a light toward the document and then the light is reflected by the reflection mirror mounted in the second traveling module  5 b. 
     The first and second traveling modules  5 a,  5 b are arranged to achieve a necessary scanning optical path during scanning. Typically, the first and second traveling modules  5 a,  5 b may be moved by a conventional driving motor via a transmission rope (not shown). In general, the ratio of the speed of the first traveling module  5 a to the speed of the second traveling module  5 b is 2:1. 
     In general, a flat cable  6  is connected between the traveling module  5 a and the protective cover  3 . The protective cover  3  contains therein a circuit board and relevant electronic components. One end of the flat cable  6  is connected to a connector socket  61  of the traveling module  5 a, and the other end of the flat cable  6  is extended into the protective cover  3  via an opening  31  formed on the protective cover  3 . So, the traveling module  5 a can via the flat cable  6  obtains necessary controlling signals and electric power source from the electronic components arranged in the protective cover  3 . 
     Generally, in order to minimize the length of the flat cable, the opening  31  on the protective cover  3  is located at a substantially middle section of the scanner. 
     Due to the material of the flat cable  6  itself, in the using regulation, the minimum curvature radius and the tolerable number of bending time of the flat cable  6  are limited. Under the connection structure of the conventional flat cable described above, since the traveling module  5 a needs to frequently move left and right, the flat cable  6  will be repeatedly bent during scanning. In the case of excess bending angle, the flat cable  6  may be broken or damaged. 
     Moreover, the width of the existing flat cable is narrower and narrower (the number of pins is reduced) with longer length (such as used in scanning of A3 size document). Therefore, during the movement of the traveling modules, the flat cable is likely to curve and touch other components (such as the bottom surface of the document positioning plate of the scanner). In addition, the flat cable may swing left and right during movement of the traveling modules. These all lead to lowered reliability and shortened using life of the scanner. 
     SUMMARY OF THE INVENTION 
     It is therefore a primary object of the present invention to provide a protective structure for preventing the flat cable of the traveling module from bending by an excess bending angle. Therefore, during the displacement of the traveling module, the end section of the flat cable is protected from being damaged due to excess bending angle. 
     It is a further object of the present invention to provide the above protective structure which is able to make the flat cable smoothly bent without collision and abrasion during movement of the traveling module. 
     It is still a further object of the present invention to provide the above protective structure which is able to guide the flat cable to smoothly move along with the traveling module without deflection. 
     To achieve the objects above, the protective structure in accordance with a preferred embodiment of the present invention includes an anti-bending member mounted onto the traveling module for preventing the flat cable from being over-bent at its first end. In addition, a guide channel member is disposed on the protective cover under the flat cable and along the moving direction of the traveling module for guiding the flat cable during moving of the traveling module and preventing the flat cable from being swung left and right. The second end of the flat cable is extended into the protective cover via a protective sheath fitted on the cover for preventing the second end of the flat cable from excess bending angle and keep the flat cable smoothly moving without deflection. 
     The present invention can be best understood through the following description and accompanying drawings wherein: 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a perspective view of a conventional scanner; 
         FIG. 2  is a perspective view showing that the present invention is applied to a scanner; 
         FIG. 3  is a perspective exploded view showing the anti-bending member of the present invention is mounted on a side wall of the traveling module; 
         FIG. 4  is a perspective enlarged view of the guide channel structure of the present invention; 
         FIG. 5  is a perspective enlarged view of the protective sheath of the present invention; 
         FIG. 6A  is a side view showing that the traveling module is positioned on a left side of the protective cover of the present invention; 
         FIG. 6B  is a side view showing that the traveling module  5 a moves rightward to an upper position on the protective cover  3 ; and 
         FIG. 6C  is a side view showing that the traveling module is positioned on a right side of the protective cover of the present invention. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
     With reference to  FIG. 2 , it is a perspective view showing that the protective structure is applied to an optical image scanning device in accordance with a preferred embodiment of the present invention. In the housing  1  of the scanner, there are provided with a focusing lens  2 , a protective cover  3 , two corresponding guide rods  4 a,  4 b, two traveling modules  5 a,  5 b and a flat cable  6 . The first end of the flat cable  6  is connected to the connector socket  61  of the travelling module  5 a, and the second end of the flat cable  6  is extended into the protective cover  3  via an opening formed on the protective cover  3 . 
     An anti-bending member  7  is additionally mounted on a side wall of the traveling module  5 a in accordance with the preferred embodiment of the present invention. The anti-bending member  7  serves to prevent the flat cable  6  from being bent by an excess bending angle at this end section. 
     Referring to  FIG. 3 , the anti-bending member  7  has an arch section and integrally extends from a bottom edge of a fixing board  71 . A circuit board  72  disposed with a connector socket  61  together with an insulating board  73  and the fixing board  71  is fixed on the front side wall of the traveling module  5 a by conventional fixing measure such as screws. After these components are assembled, the first end of the flat cable  6  is inserted into a connector socket  61  on the circuit board  72 . At this time, the end section of the flat cable  6  is supported on the arch section of the anti-bending member  7 . By means of the anti-bending member  7 , when the flat cable  6  is subject to a pulling force, the bending angle of the flat cable  6  is limited by the arch section of the anti-bending member  7  and thus the flat cable  6  is prevented from being bent by an excess bending angle. 
     In addition, a guide channel member  8  is arranged on the protective cover  3  under the flat cable  3  and along the moving direction of the traveling module  5 a in accordance with the preferred embodiment of the present invention. Therefore, when the traveling module  5 a displaces, the guide channel member  8  serves to guide the flat cable  6  to bend smoothly without deflection. 
       FIG. 4  is an enlarged view of the guide channel member  8  which includes a guide channel base seat  80  and two vertical guide walls  81 ,  82  formed on two lateral edges of the base seat  80 . The vertical guide walls  81 ,  82  are respectively formed with arch inner wall surfaces  81 a,  82 a defining a guiding structure for guiding the flat cable without intervening with the passing of the flat cable through the channel member  8 . 
     Furthermore, a protective sheath  9  is additionally located at the opening  31  formed on the protective cover  3  in accordance with the preferred embodiment of the present invention.  FIG. 5  is an enlarged view of the protective sheath  9 , showing that the protective sheath  9  is separated from the protective cover  3 . The second end of the flat cable  6  is extended into the protective cover  3  via the protective sheath  9  and the opening  31  formed on the protective cover  3  in sequence, and then electrically connect with the circuit board (not shown) arranged in the protective cover  3 . 
     When the flat cable  6  moves along with the traveling module  5 a, the protective sheath  9  serves to keep the flat cable  6  smoothly moving without deflection and prevent the second section of the flat cable  6  from being bent by an excess bending angle. 
     As shown in  FIG. 5 , the protective sheath  9  is provided with two wings  90 a,  90 b extend from two bottom sides of the protective sheath  9 . Two screws  92 a,  92 b are respectively passed through holes  91 a,  91 b formed on the wings  90 a,  90 b to lock the protective sheath  9  on the protective cover  3  at location of the opening  31 . 
       FIG. 6A  shows that the traveling module  5 a is positioned on left side of the protective cover  3 . At this position, the first end of the flat cable  6  is supported by the anti-bending member  7  so that the flat cable  6  is prevented from being over-bent at the first end section. The guide channel member  8  is just positioned at a substantially middle section of the flat cable  6  and extends in a direction of the flat cable  6 , so that by means of its own weight and flexibility, the flat cable  6  can smoothly attach with the guide channel member  8 . 
       FIG. 6B  shows that the traveling module  5 a moves rightward to an upper position on the protective cover  3 . At this time, the flat cable  6  is still able to smoothly attach with the guide channel member  8  and is guided thereby, so that the flat cable  6  is prevented from being swung left and right. 
     When the traveling module  5 a further moves rightward to a right side position of the protective cover  3 , as shown in  FIG. 6C , the middle second of the flat cable  6  is pulled and may partially separate from the guide channel member  8 . However, most portions of the flat cable  6  can still attach with the guide channel member  8  and can be guided thereby. Therefore, the flat cable  6  is still prevented from swinging left and right. When the traveling module  5 a is moved to the right dead end, by means of the protective sheath  9 , the flat cable  6  is prevented from being bent by excess bending angle at its second end section. Also, the problem of left and right swinging of the flat cable  6  taking place during movement of the traveling module  5 a can be solved. 
     The above embodiment is only used to illustrate the present invention, not intended to limit the scope thereof. Many modifications of the above embodiment can be made without departing from the spirit of the present invention.