Abstract:
A fan assembly mechanism is disclosed for mounting a fan member on a wall mounting surface of a casing, including the fan member having a flat mounting surface and a space for receiving at least one fan; at least one fastening member formed on the flat mounting surface; and an elastic fastener having its one side fixed on the fan member and at least one latching portion protruded out of the flat mounting surface. The fan assembly mechanism allows the fastening member to engage a corresponding hole on the wall mounting surface of the casing, and the latching portion to engage another hole on the casing, so as to assemble the fan member to the casing.

Description:
This Nonprovisional application claims priority under 35 U.S.C. § 119(a) on Patent Application No(s). 092204993 filed in TAIWAN on Mar. 31, 2003, the entire contents of which are hereby incorporated by reference. 
   FIELD OF THE INVENTION 
   The invention relates to fan assembly mechanisms, and particularly to an improved assembly mechanism enabling fan members to be easily mounted on and dismantled from the casing of an electronic device. 
   BACKGROUND OF THE INVENTION 
   Generally, a computer system or an electronic device has a variety of IC parts installed inside the casing thereof, such as a CPU, a power supply, and a circuit board whereon various electrical components are mounted. A great quantity of heat is generated during computer operation when electric current flows through electric circuits, which are densely placed in chips or on a circuit board. Therefore, to achieve the objective of reducing operating temperature, a fan member must be installed in a computer system or an electronic device to circulate air and radiate heat; otherwise accumulated heat inside the casing of a computer system or an electronic device during operation will raise the temperature and shorten the life-span of computer chips or other electrical components. Moreover, serious damage may be caused by burnout of computer chips or electric circuits; thereby a computer or an electronic device can immediately fail to operate thereafter. 
   The aforesaid conventional fan member is installed inside the casing of a computer system or an electronic device for radiating heat as shown in  FIG. 1 . Such conventional fan member is composed of a square-shaped frame, a motor, which is installed inside the frame for generating rotary power, and fan blades coupled with a motor transmission shaft. The motor generates power from electric current, thereby revolving the fan blades to circulate air and generate airflow, thereby exhausting the heat generated inside the casing of a computer system or an electronic device. Consequently, such fan member achieves the objective of maintaining an acceptable operating temperature inside the computer system or electronic device during operation. 
   The assembly method of the aforesaid conventional cooling fan is shown in  FIG. 1 . The said computer fan member  2  has a strip  201  installed on a lateral side of a frame  20 . A rail rest  203  is correspondingly installed inside the casing of a computer system or an electronic device, enabling the strip  201  of the fan member  2  to be slid into a track  204  established between the casing and the rail rest  203 . Moreover, the fan member  2  is secured to a rack  206  of the casing by a screw  205  penetrating a hole  207  on the rack  206 . During the assembly process of such conventional fan member, a technician has to carefully direct the strip  201  of the fan member  2  into the track  204  of the rail rest  203  such that the strip  201  can be smoothly slid into and fixed with the rail rest  203  by the screw  205 . This assembly process, however, consumes a great amount of time and labor. Another problem during assembly is that the screw could easily be dropped or lost. So, it is obvious that the assembly process of such conventional fan member  2  needs to be improved. 
   Another conventional fan member assembly is shown in  FIG. 2 . A rack  301  has a sheet metal cover  302  bent and coupled to the rack  301  inside the casing of a computer system. A space is created by the cover  302  and the rack  301  whereon the bent cover  302  is secured such that the fan member  3  can be installed inside. In that the aforesaid sheet metal cover  302  occupies large space inside a computer system, the space for placing other electrical components is reduced prior to installation of the fan. Therefore, this assembly method makes it difficult to design a system with less volume. Currently, computer product design aims at shrinking the volume and providing exquisite appearance, but such conventional fan member installation impedes creating small, attractive design and, therefore needs to be improved. 
   Consequently, it is greatly desired to develop an integrally formed fan assembly mechanism with the advantages of reducing the cost and space necessary for assembling components inside an electronic device while allowing rapid assembly and disassembly. 
   SUMMARY OF THE INVENTION 
   An objective of the present invention is to provide a fan assembly mechanism that can be rapidly mounted on and dismantled from a casing of an electronic device. 
   Another objective of the present invention is to provide an integrally formed fan assembly mechanism. 
   Another objective of the present invention is to provide a fan assembly mechanism that can be on the casing without using screws. 
   Another objective of the present invention is to provide a fan assembly mechanism that is space-effectively occupied. 
   To achieve the aforesaid and other objectives, the present invention provides a fan assembly mechanism for assembling at least one fan member on a wall mounting surface of a casing. The fan assembly mechanism comprises: (1) the fan member having a flat mounting surface and a space for receiving at least one fan; (2) one or more fastening members formed on the flat mounting surface, which can be engaged with corresponding holes on the wall mounting surface of the casing to assemble the fan member to the casing; and (3) an elastic fastener having one side thereof fixed on the fan member and at least one latching portion protruded out of the flat mounting surface. The elastic fastener is moved in a direction away from the wall mounting surface when an adjustable end of the elastic fastener is pressed down by a user during assembling the fan member to the casing, such that the elastic fastener generates an elastic force. When the pressure is released, the stored elastic force allows the elastic fastener to return to its original position, making the latching portion engaged with another corresponding hole on the wall mounting surface of the casing, and thus the fan member is assembled to the casing. 
   The elastic fastener is located in the space of the fan member, with the latching portion protruded from the flat mounting surface. At least an open trough is formed on a surface of the fan member abutting upon the flat mounting surface, such that the elastic fastener is exposed via the open trough and can be pressed by the user. The fastening members can be integrally formed with the fan member and located on edges or corners of the flat mounting surface at symmetrical positions to optimally position the fan member. 
   Consequently, the fan assembly mechanism formed with the fastening members and the elastic fastener according to the invention can adequately resolve the technique problems occurring in the above prior art so as to decrease the cost and occupied space for assembling components, and allow rapid mounting and dismantling of the fan member on and from the casing of an electronic device. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention can be more fully understood by reading the following detailed description of the preferred embodiments, with reference made to the accompanying drawings, wherein: 
       FIG. 1  (PRIOR ART) is a perspective view of a conventional fan assembly mechanism; 
       FIG. 2  (PRIOR ART) is a perspective view of another conventional fan assembly mechanism; 
       FIG. 3  is a perspective view of a fan assembly mechanism according to the invention; 
       FIG. 4  is a perspective view of a casing used with the fan assembly mechanism according to the invention; 
       FIG. 5  is a perspective view showing the assembly of the casing and a fan member of the fan assembly mechanism according to the invention; and 
       FIG. 6  is a perspective view showing the assembly of the casing and a plurality of the fan members according to the present invention. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   A preferred embodiment of the present invention is shown in  FIG. 3  wherein a fan assembly mechanism  1  comprises a fan member  10  formed with an interior space  120  enabling fan blades and a motor (not shown) to be installed for performing air circulation and heat radiation. The fan member  10  has a flat mounting surface  100  thereof affixed on a wall mounting surface  106  of the casing of an electronic device  105 . The flat mounting surface  100  has four corners thereof respectively formed with fasteners, which are integrally formed with the fan member  10  and include first fastening members  101  positioned on the upper corners of the fan member  10  and corresponding second fastenings  102  positioned on the lower corners. The first fastening members  101  protrude outward and then downward from the flat mounting surface  100  forming recessed portions; while the second fastening members  102  protrude downward from the flat mounting surface  100  forming hook-like portions. 
   In addition, the fan assembly mechanism  1  comprises an elastic fastener  103 , which is installed inside the space  120  and integrally formed with the casing of the fan member  10  using the same plastic material. The elastic fastener  103  has one side thereof placed into a narrow opening  104   a  on a lateral side of the fan member  10  and has the adjustable end thereof formed with an inclined and depressed surface  103   b  with a perpendicular recess. Meanwhile, the elastic fastener  103  has a latching portion  103   a  protruding from the flat mounting surface  1   q   00 ; whereas the other portions thereof are contained inside the space  120 . The elastic fastener  103  is movable inside the space  120  in the direction away from the wall mounting surface  106  using its immovable end as fulcrum, when the inclined and depressed surface  103   b  is under pressure. The elastic fastener  103  is sequentially returned to its original position by dint of an elastic force when the pressure is released, thereby enabling the latching portion  103   a  to again protrude out of the flat mounting surface  100 . The fan member  10  has troughs  104  respectively on both sides of its top surface, which creates a room inside the space  120  enabling the elastic fastener  103  to be moved and enabling a user to directly put pressure on the elastic fastener  103  using the inclined and depressed surface  103   b.    
   Therefore, the fan member  10  can be attached to the casing  105  of an electronic device, such as a computer system, by dint of the fan assembly mechanism  1 . As shown in  FIG. 4 , the wall mounting surface  106  of the casing  105  enables the fan member  10  to be mounted thereon by adjoining it with the flat mounting surface  100 . Moreover, the wall mounting surface  106  has holes formed thereon, including first holes  105   a  and second holes  105   b , wherein the first holes  105   a  correspond to the first fastening members  101  and the second holes  105   b  correspond to the second fastening members  102 . The openings of the first holes  105   a  are slightly plumbed with the wall mounting surface  106 , thereby enabling the first fastening members  101  to be secured; whereas the second holes  105   b  are opened on the wall mounting surface  106  enabling the second fastening members  102  to be received therein. In addition, the position on the wall mounting surface  106  of the casing  105  corresponding to that of the latching portion  103   a  on the elastic fastener  103  has a hole  105   c , whose size can be exactly matched to the latching portion  103   a  of the elastic fastener protruding from the flat mounting surface  100 , enabling the latching portion  103   a  to be wedged inside the hole  105   c  and enabling the fan member  10  to be fixed on the casing  106 . 
   Therefore, when a user installs the fan member  10  on the casing  105  using the fan assembly mechanism  1 , the first fastening members  101  of the fan member  10  can be tightly wedged into the first holes  105   a  of the wall mounting surface  106  on the casing, thereby the fan member  10  is positioned on the mounting position of the casing  105 . Sequentially, the user can place the second fastening members  102  of the fan member  10  into the second holes  105   b  on the wall mounting surface  106 , thereby wedging the four corners on the flat mounting surface  100  of the fan member  10  into the mounting positions. The fan member  10  is well positioned at this stage, but awaits being securely hooked in as the fan member is not fully mounted and might fall down under pressure or during the moving process. Therefore, the user can further press on the inclined and depressed surface  103   b  of the elastic fastener  103  of the fan assembly mechanism  1  through the open trough  104 ; the direction of pressure shall follow the same direction of the inclined and depressed surface  103   b , thereby enabling the elastic fastener inside the space  120  to be moved in the direction away from the wall mounting surface  106 , thereby the elastic fastener  103  stores elastic force resulting from the movement under pressure. The latching portion  103   a  protruded out of the flat mounting surface  100  is then moved backwards and enters inside the space  120 . Therefore, when the pressure on the elastic fastener  103  is released, the elastic fastener  103  returns back to its original position due to its own elastic force, thereby enabling the latching portion  103   a  to be returned back to the position of protruding out of the flat mounting surface  100  of the fan member  10 . Consequently, the fan member  10  is positioned on the wall mounting surface  106  of the casing  105  by means of the first fastening members  101  and the second fastening members  102 , so that the latching portion  103   a  on return back to its original position can be wedged into the corresponding hole  105   c  on the wall mounting surface  106 , thereby the fan member  10  is securely fixed by five mechanisms, which are both of the first fastening members  101 , both of the second fastening members  102 , and the latching portion  103   a  of the elastic fastener  103 . 
   The aforesaid assembly process is an easy and labor-saving method; meanwhile, the assembly has the advantage of the precise positioning without deviation, wherein it can be implemented by simply fastening and hooking in the fan member on the casing. The invention is more convenient compared to the conventional technique. Moreover, the integrated design of the invention avoids the possibility of lost parts, e.g., screws, etc., and does not exhibit the possibility of fasteners separating into pieces due to joint material and centralized stress. In addition, the operation of dismantling the fan member  10  employs the same steps as that of assembling, but in reverse order. 
     FIG. 5  is the perspective view showing the completed assembly of the fan member  10  on the casing  105  from the back of  FIG. 4 , i. e., a perspective view showing the reverse side of the wall mounting surface  106  from the backside of the casing  105 . It clearly shows the fan member  10  positioned on the wall mounting surface  106  by the first fastening members  101 , the second fastening members  102  and the latching portion  103   a  of the elastic fastener  103 . 
     FIG. 6  is the perspective view showing multiple (two) fan members  10  on the same casing  105  according to the present invention. The invention enables the wall mounting surface  106  on the casing  105  to be formed with a plurality of sets of mounting holes for installing a plurality of fan members  10  thereon according to the user requirement. Each fan member  10  can be coupled with its adjacent fan member(s), all of which are positioned on pre-set positions, each position employing the first fastening members, the second fastening member and the latching portion of elastic fastener designed by the invention to achieve said assembling and dismantling effects. Meanwhile, the deployment of those fan members can minimize the distance between adjacent fan members  10 . In that each lateral side of a fan member  10  is a plane surface, the volume of the fan members  10  inside the casing of a computer system or an electronic device can be minimized; in addition, the number of fan members can be flexibly adjusted according to the amount of heat generated inside the casing during operation. The invention, therefore, has the advantages of convenience and flexibility for easily assembling or dismantling fan members, as well as the benefit of being able to easily increase or decrease the number of fan members inside the casing. 
   Therefore, it can be concluded that the fan assembly mechanism of the present invention enables fan members to be easily and rapidly mounted and dismantled; moreover, this kind of integrated design without depending on screws further reduces assembly costs and the number of parts; meanwhile, it minimizes the space occupied by fan members installed inside the casing. 
   It is to be understood that the embodiment described herein is merely illustrative of the principles of the invention and that a wide variety of modifications thereto may be effected by persons skilled in the art without departing from the spirit and scope of the invention as set forth in the following claims, such as changing the number of and the positions of the fastening members and elastic fasteners.