Patent Publication Number: US-2010127147-A1

Title: Supporting mechanism of scanning apparatus

Description:
FIELD OF THE INVENTION 
     The present invention relates to a scanning apparatus, and more particularly to a supporting mechanism of a scanning apparatus. 
     BACKGROUND OF THE INVENTION 
     With digitalized trend, scanning apparatuses such as image scanners, multifunction peripherals or printers are widely used for scanning images of documents. The scanned images can be converted into digital electronic files, which are then stored in a computer. 
     Conventionally, a scanning apparatus comprises a base and an upper cover. After the upper cover is uplifted, the user may place a document on the base of the scanning apparatus. As such, the image of the document may be scanned by a scanning module within the base and the scanned image of the document is then converted into a digital electronic file. After the scanning operation is completed, the upper cover should be uplifted again in order to withdraw the document. In other words, for facilitating introducing or withdrawing the document, the upper cover should be uplifted and then supported by the user&#39;s hand such that a space is retained between the upper cover and the base. As known, it is usually troublesome for the user to use his or her hand to support the upper cover during the procedure of introducing or withdrawing the document. For solving these drawbacks, a scanning apparatus with a supporting mechanism has been disclosed. 
       FIG. 1  is a schematic perspective view illustrating the supporting mechanism of a scanning apparatus according to the prior art. As shown in  FIG. 1 , the scanning apparatus  1  principally comprises a base  11 , an upper cover  12  and a supporting mechanism  10 . The supporting mechanism  10  is arranged between the base  11  and the upper cover  12 . In a case that the upper cover  12  is uplifted, the upper cover  12  is supported by the supporting mechanism  10 . Moreover, the supporting mechanism  10  includes a support frame  13  and a fixing part  14  (as shown in  FIG. 2 ). An end of the support frame  13  is fixed on the upper cover  12 . The other end of the support frame  13  is connected to the fixing part  14 . The fixing part  14  is inserted into a recess of the base  11  and movably coupled with the base  11  such that the support frame  13  is fixed between the upper cover  12  and the base  11 . Once the upper cover  12  is uplifted, a space is retained between the upper cover  12  and the base  11  for facilitating introducing or withdrawing a document to be scanned. 
     Although the supporting mechanism  10  is effective for supporting the upper cover  12 , there are still some drawbacks. For example, whenever the upper cover  12  is opened (or uplifted) and closed, the support frame  13  and the fixing part  14  may collide with and rub against the base  11 . After a long use period, some powdery crumbs are readily peeled off the supporting mechanism  10 . If the powdery crumbs enter into the interior of the scanning apparatus  1 , the scanning quality is deteriorated or even the scanning apparatus is damaged. In addition, the support frame  13  and the fixing part  14  are possibly deformed if the support frame  13  and the fixing part  14  rub against the base  11  for a long use period. When serious deformation occurs, the fixing part  14  fails to be fixed onto the base  11 , and thus the fixing part  14  is detached from the base  11  (as shown in  FIG. 2 ). Moreover, if the supporting mechanism  10  is damaged, the engaging part (not shown) of the base  11  to be engaged with the fixing part  14  should be replaced with a new one. Under this circumstance, both of the supporting mechanism  10  and the base  11  need to be replaced. The replacement of the supporting mechanism  10  and the base  11  may increase the cost of the scanning apparatus. 
     Therefore, there is a need of providing an improved supporting mechanism of a scanning apparatus so as to obviate the drawbacks encountered from the prior art. 
     SUMMARY OF THE INVENTION 
     It is an object of the present invention to provide a supporting mechanism of a scanning apparatus so as to prevent damage of the base. 
     In accordance with an aspect of the present invention, there is provided a supporting mechanism of a scanning apparatus. The scanning apparatus includes a base and an upper cover. The upper cover is pivotally coupled to the base and foldable with respect to the base. The supporting mechanism includes a cam rail, a stopping plate, a support frame and a spring. The cam rail is disposed on the base. The cam rail has an open position and a close position. The stopping plate is disposed within the cam rail. The support frame includes a protrusion, which is formed on a first end thereof and accommodated in the cam rail. A second end of the support frame is connected to the upper cover. The spring is connected to the second end of the support frame and sustained against the upper cover to exert an elastic force on the support frame. When the protrusion is located at the close position and the upper cover is uplifted, the protrusion is stopped by the stopping plate and slides from the close position to the open position in a first direction. When the protrusion is located at the open position and the upper cover is continuously uplifted, the protrusion continuously slides in the first direction through the stopping plate to the close position. 
     In an embodiment, the stopping plate includes a slant and a stopper. The slant ascends in the first direction for allowing the protrusion to slide thereon in the first direction. The stopper is used for stopping the protrusion such that the protrusion is permitted to slide in the first direction. 
     In an embodiment, a first included angle is formed between the upper cover and the base when the protrusion is located in the open position. 
     In an embodiment, a second included angle is formed between the upper cover and the base during the protrusion slides from the open position to the close position, wherein the second included angle is larger than the first included angle. 
     In an embodiment, the support frame further includes a first fixing post and a second fixing post. The first fixing post and a second fixing post are formed on a second end of the support frame and partially embedded into the upper cover for connecting the support frame and the upper cover. 
     In an embodiment, the spring is arranged between the first fixing post and the second fixing pos. The spring has a first spring pin sustained against the support frame and a second spring pin sustained against the upper cover so as to exert the elastic force on the support frame. 
     Preferably, the scanning apparatus is an image scanner, a multifunction peripheral or a printer. 
     In an embodiment, the first direction is an anti-clockwise direction. 
     The above objects and advantages of the present invention will become more readily apparent to those ordinarily skilled in the art after reviewing the following detailed description and accompanying drawings, in which: 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a schematic perspective view illustrating the supporting mechanism of a scanning apparatus according to the prior art; 
         FIG. 2  schematically illustrates the detachment of the supporting mechanism from the base of the scanning apparatus shown in  FIG. 1 ; 
         FIG. 3  is a schematic view illustrating a supporting mechanism of a scanning apparatus in a close status according to a first preferred embodiment of the present invention; 
         FIG. 4  is a schematic partially exploded view illustrating the supporting mechanism of the scanning apparatus according to the present invention; 
         FIG. 5  is a schematic perspective view illustrating the supporting mechanism of the scanning apparatus in the close status according to the present invention; 
         FIG. 6  is a schematic partial perspective view illustrating the cam rail and the stopping plate of the scanning apparatus according to the present invention; 
         FIG. 7  is a schematic side view illustrating the supporting mechanism of the scanning apparatus in an open status according to the present invention; and 
         FIG. 8  is a schematic side view illustrating the supporting mechanism of  FIG. 7  during the process of switching from the open status to the close status. 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       FIG. 3  is a schematic view illustrating a supporting mechanism of a scanning apparatus in a close status according to a preferred embodiment of the present invention. The scanning apparatus  2  principally comprises a base  21  and an upper cover  22 . The upper cover  22  is pivotally coupled to the base  21  and foldable with respect to the base  21 . As shown in  FIG. 3 , the upper cover  22  is laid on the base  21  and the scanning apparatus  2  is in a close status. 
       FIG. 4  is a schematic partially exploded view illustrating the supporting mechanism of the scanning apparatus according to the present invention. As shown in  FIG. 4 , the supporting mechanism  20  of the scanning apparatus  2  comprises a cam rail  23 , a stopping plate  24 , a support frame  25  and a spring  26 . The cam rail  23  is disposed on the base  21 . The cam rail  23  has an open position OP and a close position CP. The stopping plate  24  is disposed within the cam rail  23 . The stopping plate  24  has a slant  241  and a stopper  242  (as shown in  FIG. 6 ). A protrusion  251  is formed on a first end of the support frame  25 . A first fixing post  252  and a second fixing post  253  are formed on a second end of the support frame  25 . The spring  26  is connected to the second end of the support frame  25  and sustained against the upper cover  22  to exert an elastic force on the support frame  25 . The spring  26  has a first spring pin  261  and a second spring pin  262 . 
       FIG. 5  is a schematic perspective view illustrating the supporting mechanism of the scanning apparatus in the close status according to the present invention. Please refer to  FIG. 4  and  FIG. 5 . The protrusion  251  on the first end of the support frame  25  is accommodated in the cam rail  23 . The first fixing post  252  and the second fixing post  253  on the second end of the support frame  25  are coupled to the upper cover  22 , so that the support frame  25  is fixed onto the upper cover  22 . The spring  26  is arranged between the first fixing post  252  and the second fixing post  253 . The first spring pin  261  is sustained against the support frame  25  and the second spring pin  262  is sustained against the upper cover  22 , so that the spring  26  exerts an elastic force on the support frame  25 . Due to the elastic force, the support frame  25  is movable in the cam rail  23 . In a case that the scanning apparatus  2  is in the close status, the protrusion  251  is located at the close position CP. When an upward force is exerted on the upper cover  22  to uplift the upper cover  22 , the protrusion  251  is stopped by the stopping plate  24  and thus slides from the close position CP in a first direction F. In this embodiment, the first direction F is an anti-clockwise direction.  FIG. 6  is a schematic partial perspective view illustrating the cam rail and the stopping plate of the scanning apparatus according to the present invention. As shown in  FIG. 6 , the stopping plate  24  is disposed above the close position CP. By the stopper  242  of the stopping plate  24 , the protrusion  251  is hindered from being moved in the clockwise direction. 
     Since the protrusion  251  is stopped by the stopping plate  24 , the elastic force offered by the spring  26  will cause the upward force to slide the protrusion  251  along the cam rail  23  in the first direction F. As the protrusion  251  slides, the support frame  25  and the upper covered are moved. Until the protrusion  251  is slides from the close position CP to the open position OP along the cam rail  23 , the upper cover  22  is uplifted and the supported by the support frame  25 . As a consequence, the upper cover  22  is retained in the open status and a first included angle A 1  is formed between the upper cover  22  and the base  21  (as shown in  FIG. 7 ). In this embodiment, a concave structure is formed in the sidewall of the cam rail  23  adjacent to the open position OP. When the protrusion  251  slides to the open position OP, the protrusion  251  is partially received the concave structure adjacent to the open position OP. Under this circumstance, the protrusion  251  stops sliding and the protrusion  251  is positioned at the open position OP. 
     On the other hand, for closing the upper cover, the user may slightly raise the upper cover  22 . The elastic force generated by the spring  26  will cause the protrusion  251  continuously slides from the open position OP in the first direction F (anti-clockwise direction). When the protrusion  251  is moved to the uppermost position of the cam rail  23 , a second included angle A 2  is formed between the upper cover  22  and the base  21  (as shown in  FIG. 8 ), wherein the second included angle A 2  is larger than the first included angle A 1 . 
     The protrusion  251  continuously slides from the uppermost position in the first direction F to the stopping plate  24 . Since the slant  241  of the stopping plate  24  ascends in the first direction F, the protrusion  251  will continuously glide on the slant  241  while compressing the slant  241 . Afterwards, the protrusion  251  passes through the slant  241  to the close position CP and the scanning apparatus is in the close status again (as shown in  FIG. 3 ). At this moment, the protrusion  251  is hindered by the stopper  242  of the stopping plate  24  from being moved in the clockwise direction. 
     In the above embodiments, the supporting mechanism  20  of the scanning apparatus  2  of the present invention utilizes a cam rail  23  to guide the support frame  25 . In addition, by means of the stopping plate  24  and the spring  26 , the protrusion  251  of the support frame  25  is permitted to slide in the first direction F (anti-clockwise direction). By slightly uplifting the upper cover  22 , the operating mode of the support frame  25  is switched. That is, the supporting mechanism  20  is operated without difficulty. Since the cam rail  23  is mounted on the base  21 , the support frame  25  will no longer collide with or rub against the base  21  even if the upper cover  22  is frequently opened or closed. In other words, only the support frame  25  and the cam rail  23  are possibly damaged from abrasion between the support frame  25  and the cam rail  23 . Since the cam rail  23  is an independent component mounted on the base  21 , the base  21  can be well maintained. Under this circumstance, only the support frame  25  and the cam rail  23  need to be replaced, but the base  21  needs not be replaced with a new one. 
     From the above description, the supporting mechanism of the scanning apparatus of the present invention has a simplified structure and easily operated. In addition, the process of replacing the support frame or the cam rail is very simple. Since the base needs not be replaced with a new one, the scanning apparatus of the present invention is more cost-effective. 
     While the invention has been described in terms of what is presently considered to be the most practical and preferred embodiments, it is to be understood that the invention needs not be limited to the disclosed embodiment. On the contrary, it is intended to cover various modifications and similar arrangements included within the spirit and scope of the appended claims which are to be accorded with the broadest interpretation so as to encompass all such modifications and similar structures.