Patent Publication Number: US-2013250530-A1

Title: Electronic device having sensor window cover

Description:
BACKGROUND 
     1. Technical Field 
     The present disclosure relates to electronic devices, and particularly to an electronic device having a sensor window cover. 
     2. Description of Related Art 
     Electronic devices, such as DVD players, may include a housing and a sensor window cover secured to the housing. The sensor window cover includes a hook member. The housing defines an area to be covered by the sensor window cover, and includes a latching member arranged adjacent to the area. The latching member corresponds to the hook member and hooks the hook member to secure the sensor window cover to the housing. However, if the sensor window cover is made of brittle materials such as polymethyl methacrylate, the sensor window cover may be broken when being secured to the housing. 
     Therefore, there is room for improvement in the art. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       Many aspects of the embodiments can be better understood with reference to the following drawings. The components in the drawings are not necessarily drawn to scale, the emphasis instead being placed upon clearly illustrating the principles of the embodiments. Moreover, in the drawings, like reference numerals designate corresponding parts throughout the seven views. 
         FIG. 1  is a partial perspective view of an electronic device having a sensor window cover in accordance with an embodiment. 
         FIG. 2  is a partially disassembled view of the electronic device of  FIG. 1 . 
         FIG. 3  is similar to  FIG. 2 , but viewed from another aspect. 
         FIG. 4  is an enlarged view of portion IV in  FIG. 3 . 
         FIG. 5  is a perspective view of the sensor window cover in  FIG. 1 . 
         FIG. 6  is a partial assembly view of the electronic device of  FIG. 2 . 
         FIG. 7  is a partially cut-away view cut away from the electronic device of  FIG. 1 . 
     
    
    
     DETAILED DESCRIPTION 
     The disclosure is illustrated by way of example and not by way of limitation in the figures of the accompanying drawings in which like references indicate similar elements. It should be noted that references to “an” or “one” embodiment in this disclosure are not necessarily to the same embodiment, and such references mean at least one. 
     Referring to  FIG. 1 , an electronic device  100  having a sensor window cover  50  is shown. Referring also to  FIGS. 2-3 , the electronic device  100  includes a housing  10 , a circuit board  30  received in the housing  10 , a signal receiving unit  40  arranged on the circuit board  30 , and a sensor window cover  50  secured to the housing  10  and corresponding to the signal receiving unit  40 . 
     The housing  10  includes a front case  101  and a rear case (not shown). The front case  101  engages with the rear case to define a receiving space  102  for receiving the circuit board  30 , the signal receiving unit  40 , and other electronic components (not shown) of the electronic device  100 . The front case  101  includes a front wall  110  and a plurality of sidewalls  120  protruding from rims of the front wall  110 . The front wall  110  defines an opening  112 . The opening  112  is substantially rectangular, and is used for securing the sensor window cover  50 . A plurality of fixing posts  130  are secured on an inner surface of the front wall  110 . Each fixing post  130  defines a fixing hole  132 . 
     The circuit board  30  is substantially rectangular, and is arranged parallel to the front wall  110 . The circuit board  30  defines a plurality of through hole  310  corresponding to the fixing holes  132 . Fixing members (such as screws, not shown) extend through the through holes  310  and are further secured to the fixing holes  132 , to fix the circuit board  30  to the front case  101 . The signal receiving unit  40  is secured to the circuit board  30  and corresponds to the opening  112 . 
     Referring to  FIG. 4 , a limiting mechanism  111  is secured to an inner surface of the front wall  110 . The limiting mechanism  111  includes two limiting posts  114 . The limiting posts  114  are perpendicularly arranged on the inner surface of the front wall  110  and are symmetrically arranged on opposite sides of the opening  112 . In the embodiment, the limiting posts  114  are aligned in a line (referred herein as the connecting line) extending along the length of the front wall  110 . The limiting mechanism  111  further includes a limiting block  115  and a stopping block  116 . Longitudinal planes of the limiting block  115  and the stopping block  116  are perpendicular to each other. The limiting block  115  and the stopping block  116  are positioned at opposite sides of the opening  112 . The limiting block  115  and the stopping block  116  are arranged at opposite side of the connecting line, with the limiting block  115  parallel to the connecting line and the stopping block  116  perpendicular to the connecting line. 
     Referring to  FIG. 5 , the sensor window cover  50  includes a base  510  and a window  520  arranged on the base  510 . The base  510  is substantially rectangular and includes a first end  511 , and a second end  512  opposite to the first end  511 . The length of the base  510  (namely the distance between the first and second ends  511 ,  512 ) is slightly less than the distance between an end of the limiting block  115  adjacent to the opening  112  and a plane where the stopping block  116  is aligned. The window  520  is arranged on a front surface  513  of the base  510  and is between the first and second ends  511 ,  512 . The size of the window  520  is slightly less than the size of the opening  112 . When viewed from the front surface  513  of the base  510 , the window  520  protrudes out of the front surface  513 ; when viewed from a rear surface  514  of the base  510 , the window  520  is recessed in the rear surface  514  of the base  510 . In the embodiment, the sensor window cover  50  is made of polymethyl methacrylate. 
     The base  510  further defines two limiting holes  516 . The limiting holes  516  are symmetrically arranged at opposite sides of the window  520 . The limiting holes  516  correspond to and receive the limiting posts  114  respectively. Two protruding blocks  517  protrude from the second end  512  of the base  510 . The protruding blocks  517  are spaced from each other to define a recess  518 . The recess  518  is substantially U-shaped and corresponds to the limiting block  115 . The recess  518  is adapted to receive the limiting block  115  when the window  520  is received in the opening  112 . The distance between the distal end of the protruding blocks  517  and the window  520  is greater than the distance between the stopping block  116  and an edge of the opening  112  adjacent to the stopping block  116 . 
     Furthermore, two supporting plates  530  are perpendicularly secured to the rear surface  514  of the base  510 . The supporting plates  530  are parallel to each other and are arranged at opposite sides of the opening  112 . In the embodiment, each supporting plate  530  is arranged between one of the limiting hole  516  and the opening  112 . Two ribs  532  are secured to the rear surface  514  of the base  510 . Each rib  532  connects with a side of one supporting plate  530  opposite to the other supporting plate  530 , to enhance the stiffness of the supporting plates  530 . 
     Referring to  FIGS. 6-7 , in assembly, the window  520  is received in the opening  112  with the limiting block  115  being received in the recess  518  and the limiting posts  114  being received in the limiting holes  516 . The circuit board  30  is secured to the fixing posts of the front wall  110  and further abuts ends of the supporting plates  530  away from the base  510  to prevent the sensor window cover  50  from disengaging with the front case  101 . 
     After assembly, the window  520  is received in the opening  112  and the limiting posts  114  is received in the limiting holes  516 , thus, the sensor window cover  50  is prevented from moving in a direction parallel to the front wall  110 . At the same time, the circuit board  30  abuts ends of the supporting plates  530  away from the base  510 , thus, the sensor window cover  50  is prevented from moving in a direction perpendicular to the front wall  110 . As a result, the sensor window cover  50  is steadily secured to the front case  101 . 
     Furthermore, because the limiting block  115  is received in the recess  518  and the stopping block  116  abuts the second end  512  of the base  510 , the sensor window cover  50  is further prevented from moving a direction parallel to the front wall  110 . Because the distance between the distal end of the protruding blocks  517  and the window  520  is greater than the distance between the stopping block  116  and the edge of the opening  112  adjacent to the stopping block  116 , the stopping block  116  stops the protruding blocks  517  from engaging therewith to prevent the sensor window cover  50  from being reversely installed. 
     It is to be understood, even though information as to, and advantages of, the present embodiments have been set forth in the foregoing description, together with details of the structures and functions of the present embodiments, the disclosure is illustrative only; and that changes may be made in detail, especially in the matters of shape, size, and arrangement of parts within the principles of the present embodiments to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.