Abstract:
An electronic device able to read an optical disc includes a base, a cover, a driving unit for rotating and supporting the optical disc, and a shutdown device. The shutdown device is arranged between the base and the cover, and includes a raster sensor and an engaging component. The engaging component is secured to the cover and pivots about the base. When the cover is opened, the engaging component moves away from the raster sensor, the raster sensor emits a first control signal in response, which controls the driving unit to stop rotating.

Description:
BACKGROUND 
       [0001]    1. Technical Field 
         [0002]    The present disclosure relates to electronic devices with a safety shutdown device. 
         [0003]    2. Description of Related Art 
         [0004]    Computer disc drives are ubiquitous. An optical disc, such as Compact Disc (CD), Digital Video Disc or Digital Versatile Disc (DVD) and Mini Disc (MD) is rotated by a driving unit such as a spindle motor provided in a disc driver and the disc driver reads/writes data from/to the optical disc. The disc drives further include a base and a cover rotatably coupled to the base. In use, the optical disc is housed inside the base by closing the cover and can be removed by opening the cover. However, when the cover is opened during rotation of the optical disc, the optical disc may jump out from the base, causing damage to the optical disc. 
         [0005]    Therefore, there is room for improvement in the art. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    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 several views. 
           [0007]      FIG. 1  is an isometric view of an embodiment of an electronic device with a shutdown device. 
           [0008]      FIG. 2  is a partial, exploded view of the electronic device of  FIG. 1 . 
           [0009]      FIG. 3  is similar to  FIG. 2 , but viewed from another aspect. 
           [0010]      FIG. 4  is a partial, cross-sectional view of the electronic device of  FIG. 1  in a first use state. 
           [0011]      FIG. 5  is similar to  FIG. 4 , but showing another use state. 
           [0012]      FIG. 6  is enlarged view of the shutdown device of  FIG. 1  in the first use state. 
           [0013]      FIG. 7  is similar to  FIG. 6 , but showing another state of use. 
       
    
    
     DETAILED DESCRIPTION 
       [0014]    Referring to  FIG. 1 , an electronic device  100  of one embodiment is shown. The electronic device  100  includes a base  10 , a cover  13 , a driving unit  15  (shown in  FIG. 2 ) and a shutdown device  17  (shown in  FIG. 4 ). The driving unit  15  is received in the base  10  and rotates an optical disc (not shown). The shutdown device  17  is arranged between the base  10  and the cover  13  for controlling the driving unit  15 . The electronic device  100  may be a disc drive in a notebook computer, or the like. In the embodiment, the electronic device  100  is a disc drive for retrieving data recorded on an optical disc. 
         [0015]    Referring to  FIGS. 2 and 3 , the base  10  in the embodiment is substantially rectangular. The base  10  includes a lower case  101  and an upper case  115  secured to the lower case  101 . The lower case  101  cooperates with the upper case  115  to define a closed space (not labeled) for receiving components of the electronic device  100 . 
         [0016]    The lower case  101  includes a bottom wall  110 , a first sidewall  111 , a second sidewall  112 , a third sidewall  113  opposite to the first sidewall  111 , and a fourth sidewall  114  opposite to the second sidewall  112 . The first, second, third and fourth sidewalls  111 ,  112 ,  113 ,  114  slantingly extend from four rims of the bottom wall  110  and connect with each other. 
         [0017]    The upper case  115  includes a top surface  1154 , a bottom surface (not labeled) opposite to the top surface  1154  and two connecting portions  1155  (shown in  FIG. 6 ). The top surface  1154  is recessed to define a rectangular first receiving portion  1150  for receiving the cover  13 . Two spaced through holes  1153  are defined at an edge of the first receiving portion  1150  adjacent to the third sidewall  113 . The bottom of the first receiving portion  1150  further defines a substantially circular second receiving portion  1151  for receiving the optical disc. The bottom of the second receiving portion  1151  further defines a mounting hole  1152 . The two connecting portions  1155  protrude from the bottom surface of the upper case  115  and are adjacent to the two through holes  1153 . A shaft  1156  is secured to each opposing surface of the two connecting portions  1155  for rotatably connecting the cover  13  to the upper case  115 . 
         [0018]    The cover  13  is rotatably coupled to the base  11 , to be opened and closed. The shape of the cover  13  corresponds to the shape of the first receiving portion  1150 . When the cover  13  rests on the base  11 , the cover  13  is received in the first receiving portion  1150 . 
         [0019]    The two hinge components  130  are secured to the cover  13  opposite to the base  11  and correspond to the two through holes  1153 . Each hinge component  130  includes a first arm  1301  and a second arm  1303 . The first arm  1301  projects from an outer edge of the cover  13  and is inclined away from the cover  13 . The second arm  1303  is bent from an end of the first arm  1301  away from the cover  13 , and is inclined toward the cover  13 . Thus, from a side view, the rotating component  130  is substantially V-shaped with an opening facing the cover  13 . An end of the second arm  1303  away from the first arm  1301  defines a pivoting hole  1306  for engaging with the shafts  1156 . 
         [0020]    The driving unit  15  is set on the bottom wall  110 , and a part protrudes out of the bottom of the second receiving portion  1151  via the mounting hole  1152 . The driving unit  15  includes a spindle motor  150  and a spindle  151  connected to the spindle motor  150 . The spindle motor  150  rotates the spindle  151 . The spindle  151  extends through the mounting hole  1152  and is exposed out of the upper case  115  for mounting the optical disc. 
         [0021]    The shutdown device  17  is arranged between the bottom wall  110  and the cover  13 . The shutdown device  17  includes two spaced raster sensors  170  and two engaging components  172 . The two raster sensors  170  are arranged on the bottom wall  110  and correspond to one of the hinge component  130  adjacent to the second sidewall  112 . Each raster sensor  170  is substantially U-shaped, and includes an emitter  1701  and a receiver  1703  opposite to the emitter  1701 . A predetermined gap  1707  is formed between the emitter  1701  and the receiver  1703 . Each of the emitter  1701  and the receiver  1703  defines two opposite openings  1705 . The emitter  1701  transmits a infrared signal via the opening  1705 , and the receiver  1703  generates a first control signal when the first infrared signal is received via the opening  1705  and generates a second control signal when a second infrared signal, different from the first infrared signal, is received. In the embodiment, since the second infrared signal can equate to no signal or to a signal with miniscule intensity, the first infrared signal is significantly stronger than the second infrared signal. 
         [0022]    The two engaging components  172  interact with the two raster sensors  170 . In the embodiment, the two engaging components  172  are two rectangular protrusion blocks. The two engaging components  172  project from the joint between the second arm  1303  and the first arm  1301  of the rotating component  130  and are opposite to the cover  13 . The thickness of each engaging component  172  in a direction parallel to the third sidewall  113  is smaller than the width of the gap  1707 . Thus, the engaging components  172  can be received in the corresponding gaps  1707 . The size of the two engaging components  172  in a direction perpendicular to the third sidewall  113  is larger than or equal to the size of the openings  1705 , such as when in front of the openings  1705  can cover or obscure the openings  1705 . 
         [0023]    Referring to  FIGS. 4 ,  5 ,  6  and  7 , in assembly, the two hinge components  130  extend through the corresponding through holes  1153 , with the two shafts  1156  pivotally receiving in the pivoting hole  1306 , for allowing the cover  13  to be rotably coupled to the upper case  115 . In this state, the cover  13  is received in the first receiving portion  1150 . The engaging components  172  are received in the gaps  1707  and obscure the openings  1705 . Thus, each receiver  1703  is prevented from receiving a complete or full infrared signal from an emitter  1701 . 
         [0024]    To replace/remove the optical disc after initial assembly, the cover  13  is rotated open, and the two engaging components  172  disengage from the raster sensors  170 . Thus, the opening  1705  becomes open and clear, an infrared signal between each emitter  1701  and each receiver  1703  can pass. The two raster sensors  170  emit the first control signal. The driving unit  15  stops rotating in response to receiving a first control signal. 
         [0025]    When the cover  13  is closed on the base  11 , the two engaging components  172  rotate toward the raster sensors  170 . The two engaging components  172  move into the corresponding gaps  1707 . The infrared signal between each emitter  1701  and receiver  1703  is substantially diminished, causing the two raster sensors  170  to emit the second control signal. The driving unit  15  rotates in response to the second control signal. The electronic device  100  starts to read the data recorded on the optical disc. 
         [0026]    In another embodiment, the number and the position of the raster sensors  170  and the engaging components  172  can be changed, such that the raster sensor  170  is arranged on the cover  13 , and the engaging component  172  is arranged on the base  11 . 
         [0027]    Although information and the 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 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.