Patent Publication Number: US-2005139348-A1

Title: Hot swap fan

Description:
BACKGROUND OF THE INVENTION  
      a. Field of the Invention  
      The present invention relates to a hot swap fan.  
      b. Description of the Related Art  
      When electronic products operate, they produce considerable heat to raise environmental temperature. This tends to lower their stability and even to cause breakdowns. Hence, a heat dissipating device such as a fan is used to maintain a suitable range of environmental temperature at which the electronic products operate.  
      Nowadays, a hot swap fan, electrically connected to a system in a terminal-contact manner instead of welding, is developed, so that it can be detached or replaced from the system easily and quickly in case of malfunction without shutting down the system.  
      However, since the space for accommodating a fan in a system is always limited, the issue of how to design a fan feasible of hot swapping with simple mechanism and compact size becomes very important.  
     BRIEF SUMMARY OF THE INVENTION  
      Therefore, an object of the invention is to provide a hot swap fan with simple mechanism, compact size, reduced manufacture cost, and improved working safety.  
      According to the invention, a hot swap fan includes a fan and a holding member. The fan has an air inlet, an air outlet, and a sidewall connected between the air inlet and the air outlet. The holding member is bent to form a top portion and at least one side portion and affixed on the sidewall. The top portion is formed with at least one handle portion, and part of the side portion is formed as a movable flexible portion connecting to the handle portion. The movable flexible portion is formed with an engaging structure to engage a casing that accommodates the hot swap fan.  
      Through the design of the invention, since the bent holding member is hollowed out to create a movable portion, namely the handle portion and the movable flexible portion connecting to the handle portion and formed with an engaging structure, the hot swap fan and the casing can be assembled and unassembled quickly through only one component, i.e. the holding member  14 . Therefore, the design for a hot swap fan is simplified, and its manufacture cost is considerable reduced as a result.  
      Moreover, the handle portion may be designed to be leveled with the holding member, so that the space occupied by the hot swap fan can be further reduced. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is an exploded view of a hot swap fan according to an embodiment of the invention.  
       FIG. 2  is an exploded view of a hot swap fan according to another embodiment of the invention.  
       FIG. 3  is an exploded view of a hot swap fan according to another embodiment of the invention.  
       FIG. 4  is an exploded view of a hot swap fan according to another embodiment of the invention.  
       FIG. 5A  is a perspective view of a hot swap fan with a fan guard.  
       FIG. 5B  is a perspective view of a hot swap fan with a fan guard standing in an upside down state.  
       FIGS. 6A-6C  are schematic views illustrating shape modifications of a terminal base.  
       FIG. 7  is a perspective view illustrating a fix method for the hot swap fan of the invention. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION  
      Referring to  FIG. 1 , a hot swap fan  10  includes a fan  12  and a holding member  14 . The fan  12  has an air inlet  12   a,  an air outlet  12   b,  and a frame  16  with a plurality of fixing holes  16   a  and a sidewall  12   c  connected between the inlet  12   a  and the outlet  12   b.  The holding member  14  is bent to form a top portion  18  and two side portions  20  to fit the shape of the sidewall  12   c , each of the side portions  20  being made an angle with the top portion  18 . A plurality of fixing holes  14   a  whose position correspond to the fixing holes  16   a  are formed on the corner of the holding member  14 . The holding member  14  is affixed on the sidewall  12   c  of the fan  12  by rivets  34  inserted in both the fixing holes  14   a  and  16   a.  Also, the rivets  34  may be replaced by screws.  
      According to the embodiment shown in  FIG. 1 , the holding member  14  is hollowed out so that the top portion  18  is formed with two ring-pulls  22  at its two sides, respectively, and that part of the side portion  20  is formed as a movable flexible portion  24  connecting to the ring-pull  22 .  
      The flexible portion  24  is formed with an engaging structure on its surface, such as a hook  26 . The hook  26  is used to engage a casing (not shown) that accommodates the hot swap fan  10 . Since the ring-pull  22  and the flexible portion  24  are connected to each other, when one puts his fingers on the two ring-pulls  22  and pulls them towards the center of the top portion  18 , the inwards movement of the ring-pulls allows the hook  26  on the flexible portion  24  to disengage from the casing. Following that the ring-pulls  22  are pressed against the center of the top portion  18  and lifted upwards, and the hot swap fan  10  is separated from the casing.  
      Through the design of the invention, since the bent holding member  14  is hollowed out to create a movable portion, namely the handle portion such as the ring-pull and the flexible portion on which an engaging structure is formed, the hot swap fan and the casing can be assembled and unassembled quickly through only one component, i.e. the holding member  14 . Therefore, the design for a hot swap fan is simplified, and its manufacture cost is considerable reduced as a result. Moreover, according to this embodiment, the ring-pulls  22  are leveled with the holding member  14 , so that the space occupied by the hot swap fan can be further reduced.  
      In addition, on the side portions  20  of the holding member  14  a raised portion  28  is provided for foolproof. The top portion  18  of the holding member  14  also provides a mounting hole  30  for housing a light-emitting diode (LED), used as an operation indication lamp of the fan  12 . Further, a terminal base  32  having at least one contact terminal is mounted on the sidewall of the fan  12  opposite to the holding member  14 . The terminal base  32  may be formed with a bump  32   a  to engage with the fixing holes  16   a.  Alternatively, the terminal base  32  and fan frame  16  may be joined together through engaging, insert molding, fusing, ultrasonic welding, riveting, or screwing. Take the insert molding as an example, the metal part of the terminal base  32  and the fan frame  16  may be positioned in a mold, and then the metal part is enclosed by plastic through injection molding to fix the terminal base  32  on the fan frame  16 .  
      Referring to  FIGS. 6A-6C , the terminal base  32  may be in an L shape  52 , a bar shape  54 , an U shape  56 , or a polygon shape having at least one opening. The terminal base  32  may be integrally formed as a single piece, as in  FIGS. 6B and 6C , or may be formed by a combination of at least two pieces  52   a  and  52   b,  as in  FIG. 6A . The material of the terminal base  32  may be transparent plastics, non-transparent plastics, colored plastics, rubber, or metal.  
      The number and shape of the hook  26  formed on the flexible portion  24  are not limited, as long as the hook  26  can properly engage a casing. Referring to  FIG. 2 , if only one hook  26  is needed to provide sufficient engaging force, only one side portion of the holding member is needed; hence, only one ring pull  22  and flexible portion  24  are formed on the holding member  14 . In that case, the LED mounting hole  30  may be set on the side of the holding member  14  without the ring pull  22 .  
      Moreover, the method for combining the holding member  14  and the fan  12  is not limited. For example, the holding member  14  may be formed with bumps  14   b  whose positions correspond to the fixing holes  16   a  to securely affix the holding member  14  on the fan  12  without the use of rivets  34 , as shown in  FIG. 2 .  
      Referring to  FIG. 3 , after the holding member  18  is hollowed out to create a movable portion, instead of the ring pull  22  shown in  FIG. 1 , one end of the movable portion is further bent to form a curved portion  36  used as the handle portion. When one&#39;s fingers grab the curved portion  36  and pull them towards the center of the top portion  18 , the inwards movement of the curved portion  36  also allows the hook  26  on the flexible portion  38  to disengage from the casing.  
      That is, the design of the holding member  14  according to the invention may vary arbitrarily, as long as it is formed with at least one handle portion and flexible portion to cause a displacement of the engaging structure.  
      Typically, a fan guard is provided to enclose a fan for improving the working safety. Referring to  FIG. 4 , a hot swap fan  40  is closely enclosed by a fan guard  42 , which includes two surfaces  44  and  46  having wide areas to cover the inlet and outlet of the fan  12  and a connecting surface  48  to connect the surface  44  to the surface  46 . These surfaces together form a shape of a square horseshoe. The fan guard  42  has a plurality of fixing holes  42   a  formed on the surfaces  44  and  46 , and the fan guard  42  may be tightly affixed to the fan frame by riveting or screwing. The combining method for the fan guard  42  and the fan  12  is not limited; for instance, the surfaces  44  and  46  may be formed with inwardly bumps instead of the fixing holes  42   a  to securely fit the fan  12  inside the fan guard  42 .  
      Referring to  FIG. 5A , since the fan guard  42  is designed to match the holding member  14 , the fan guard  42  is incorporated in the hot swap fan almost without expanding its occupied space. Moreover,  FIG. 5B  shows the terminal base  32  having at least one contact terminal  32   b.  The contact terminal  32   b  may be protruded from or hidden inside the terminal base  32  according to the actual demand, or it may even provided on a system.  
      Further, referring to  FIG. 7 , the hot swap fan  40  may be received in a casing  62  having a fastening member  64  and fixed therein through the fastening member  64 , without the need of additional fixing steps. The fastening member  64  may be a plate or an engaging structure whose one end is connected to one side of the casing  62  and the other end to the hot swap fan  40  or the other side of the casing  62 .  
      Further, according to the invention, the materials for forming the fan guard  42  and the holding member  14  include, but are not limited to, metals or plastics.  
      While the invention has been recited by way of examples and in terms of the preferred embodiments, it is to be understood that the invention is not limited to the disclosed embodiments. To the contrary, it is intended to terminal base various modifications and similar arrangements as would be apparent to those skilled in the art. Therefore, the scope of the appended claims should be accorded the broadest interpretation so as to encompass all such modifications and similar arrangements.