Patent Publication Number: US-2011073287-A1

Title: Heat dissipating device

Description:
BACKGROUND  
     1. Technical Field 
     The disclosure generally relates to heat dissipating devices, especially to a heat sink cover and a heat dissipating device using the heat sink cover. 
     2. Description of Related Art 
     Electronic devices in computers, such as central processing units (CPUs), generate a lot of heat during normal operation, which can deteriorate their operational stability, and damage associated electronic devices. Thus, the heat must be removed quickly to ensure normal operation of the CPU. Some heat dissipating devices include a heat sink mounted on a CPU to remove heat. Some heat sinks include a plurality of fins each having a corner projection. The corner projections may be hazardous during installation. 
     Therefore there is a need for improvement in the art. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
       Many aspects of the embodiments can be better understood with references 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. 
         FIG. 1  is an exploded, isometric view of a heat dissipating device of an embodiment, the heat dissipating device including a heat sink and a heat sink cover. 
         FIG. 2  is a partial enlarged, isometric view of the heat sink of  FIG. 1 , showing section II. 
         FIG. 3  is a cross section view of the heat sink cover of  FIG. 1 , taken along line III-III. 
         FIG. 4  is an exploded, isometric view of the heat dissipating device of  FIG. 1  and an enclosure. 
         FIG. 5  is an assembled view of  FIG. 4 . 
     
    
    
     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 , a heat dissipating device  10  includes a heat sink  30 , a heat sink cover  40 , and a fan  50 . 
     The heat sink  30  includes a base  31 , a plurality of fins  32  extending radially from the base  31 , and four securing portions  33  extending from the base  31 . Each securing portion  33  includes a first mounting portion  331  and a second mounting portion  332 . The first mounting portion  331  includes a fastener  3311  capable of securing the heat sink  30  to the motherboard. The second mounting portion  332  defines a securing hole  3321 . Each fin  32  is generally rectangle-shaped. As shown in  FIG. 2 , each fin  32  includes a first edge  321  and a second edge  322  perpendicular to the first edge  321 . A corner projection  323  is corporately defined by the first edge  321  and the second edge  322 . 
     The fan  50  includes four securing portion  51 . Each securing portion  51  defines a securing hole  511  therein. 
     Referring to  FIGS. 1 and 3 , the heat sink cover  40  is used to cover the corner projections  323  of the heat sink  30 . The heat sink cover  40  includes a first wall  41  and a second wall  42  perpendicularly extending from the first wall  41 . A receiving space  43  is corporately defined by the first wall and the second portion  42 . The cross section of the heat sink cover  40  is L-shaped. The first wall  41  includes four mounting portions  411 . Each mounting portion  411  defines a through hole  412  corresponding to the securing hole  3321  of the heat sink  30  and an opening  413  corresponding to the fastener  3311 . The second wall  42  has four receiving portions  422  for receiving the second mounting portions  332  respectively. The heat sink cover  40  is circular and surrounds the corner projections  323  of the heat sink  30 . 
     Referring to  FIGS. 1 to 4 , in assembly of the heat dissipating device  10 , the heat sink cover  40  is disposed on the heat sink  30  to cover the corner projection  323  of the heat sink  30 . The receiving portions  422  of the heat sink cover  40  receive the second mounting portions  332  of the heat sink  30  respectively. The openings  413  of the heat sink cover  40  align with the first mounting portions  331  of the heat sink  30  respectively. The first wall  41  of the heat sink cover  40  contacts the first edge  321  of the heat sink  30  and the second wall  42  of the heat sink cover  40  contacts the second edges  322  of the heat sink  30 . The receiving space  43  receives the corner projections  323  of the fins  32 . The securing holes  511  of the fan  50  are aligned with the through holes  412  of the heat sink cover  40  respectively. Four fasteners  60  are respectively extended through the securing holes  511  of the fan  50 , the through holes  412  of the heat sink cover  40 , and then screwed into the securing holes  3321  of the heat sink  30  to secure the fan  50 , the heat sink cover  40 , and the heat sink  30  together. 
     Referring to  FIGS. 4 and 5 , a printed circuit board  80  is placed in an enclosure  70 . The printed circuit board  80  includes a heat generating element  90  mounted thereon. The printed circuit board  80  defines four mounting holes  810  corresponding to the fasteners  3311  respectively. In assembly of the heat dissipating device  10  to the enclosure  70 , the fasteners  3311  of the heat dissipating device  10  are aligned with and screwed into the mounting holes  810  respectively to secure the heat dissipating device  10  in the enclosure  70 . 
     It is to be understood, however, that even though numerous characteristics and advantages have been set forth in the foregoing description of preferred embodiments, together with details of the structures and functions of the preferred embodiments, the disclosure is illustrative only, and changes may be made in detail, especially in matters of shape, size, and arrangement of parts within the principles of the disclosure to the full extent indicated by the broad general meaning of the terms in which the appended claims are expressed.