Patent Publication Number: US-2011049007-A1

Title: Protective case for fan

Description:
FIELD OF THE INVENTION 
     The present invention relates to a protective case for fan, and more particularly to a protective case having a case body internally provided with first and second retaining portions, so that the same protective case can be conveniently used to stably pack differently sized fans and the cost of manufacturing differently sized protective cases can be saved. 
     BACKGROUND OF THE INVENTION 
     Thanks to the prosperously developed electronic industry, various kinds of electronic elements now have upgraded performance to provide faster and faster computing and operating speed. Chipsets for different electronic elements provide constantly increased computing speed and the number of chips included in different chipsets also increases constantly. However, heat produced by the chips during the operation thereof also increases with the increased number of chips. The produced heat must be timely removed from the electronic elements to avoid adverse influences on the performance thereof, such as slowed processing speed, burned-out or failed electronic elements. Therefore, heat dissipation has become a very important issue in the electronic industry. Among others, a fan has been widely adopted as a heat dissipating device to remove the heat produced by the operating electronic elements. 
     Generally, the fan is subject to invasion by dust and foreign matters in the process of transporting, handling, or selling the fan. The invaded dust and foreign matters would inevitably move from the operating fan to different electronic elements, resulting in short circuit and burnout of the electronic elements. To solve the problems caused by the dust-invaded fan, a protective case for fan has been developed. 
     Please refer to  FIGS. 1A and 1B . A conventional protective case for fan includes a case cover  10  and a case body  12 . The case body  12  internally defines a receiving space  121  for receiving a fan  14  therein. A space  16  between an inner wall surface of the case body  12  and an outer periphery of the fan  14  is reserved in the receiving space  121  to facilitate easy and convenient positioning of the fan  14  into the receiving space  121  in the case body  12 . The case cover  10  can be closed onto an open top of the case body  12  to seal the receiving space  121 . 
     Most of currently available fans can be generally divided into two types according to their sizes, namely, large-size fans and small-size fans. Before packing a fan  14  in the case body  12 , an operator has to verify first whether the fan  14  being handled is a large-size fan or a small-size fan. In the event of a large-size fan, the operator has to select a corresponding large-size case body  12  for packing the large-sized fan  14 . Then, the fan  14  is moved toward the case body  12  until the fan  14  is positioned on a bottom of the receiving space  121 . Finally, the case cover  10  is closed onto the case body  12 . 
     In the event of a small-size fan, the operator has to select a corresponding small-size case body  12  for packing the small-size fan  14 . Then, the fan  14  is moved toward the case body  12  until the fan  14  is positioned on a bottom of the receiving space  121 . Finally, the case cover  10  is closed onto the case body  12 . 
     Therefore, while the conventional protective cases can effectively protect the fans against invasion by dust and foreign matters, the conventional protective cases must be manufactured into at least two different sizes separately for packing the large-size and the small-size fans. It requires increased cost to manufacture differently sized protective cases, and it is troublesome for an operator to verify and select a correctly sized protective case each time a fan is to be packed. 
     Moreover, with the space  16  left in the receiving space  121  between the fan  14  and the case body  12 , the fan  14  packed in the conventional protective case is not firmly held in place and tends to vibrate or shake during transportation or handling thereof. Therefore, the fan  14  is subject to displacement in and collision with the protective case and the case cover  10  is subject to loosening from the case body  12 . In some worse conditions, the fan  14  is damaged in the protective case due to such vibration or shaking. Foam materials and other shock-absorbing materials have been used to stuff the reserved space  16 , so as to prevent the fan  14  from damage caused by displacement in and collision with the case body  12 . However, the stuffing brings other problems, such as increased overall weight of the packed fan and environmental pollution caused by discarded stuffing. In some cases the protective case is made of a transparent material and in the form of a hang card for displaying the fan packed therein for sale. The foam material or other shock-absorbing material stuffed in the protective case would no doubt have adverse influence on the aesthetic appearance of the fan being displayed in the protective case, making the fan less attractive to consumers. 
     In brief, the conventional protective case for fan has the following disadvantages: (1) requiring increased manufacturing cost; (2) causing inconvenience in packing fans; (3) failing to firmly hold the fan in place; and (4) having low applicability. 
     It is therefore tried by the inventor to develop an improved protective case for fan to overcome the above-mentioned disadvantages in the conventional protective case. 
     SUMMARY OF THE INVENTION 
     A primary object of the present invention is to provide a protective case for fan that can be manufactured at reduced cost. 
     Another object of the present invention is to provide a protective case for fan that can provide enhanced locating effect to the fan packed therein. 
     A further object of the present invention is to provide a protective case for fan that can be conveniently used to pack differently sized fans. 
     To achieve the above and other objects, the protective case for fan according to a first embodiment of the present invention includes a case body having a closed bottom portion and a sidewall portion connected to and extended along a periphery of the bottom portion, so that a receiving space is defined in the case body between the bottom portion and the sidewall portion. Two first raised ribs are formed on the closed bottom portion adjacent to a first set of two opposite sides thereof, such that a first retaining portion is defined between the sidewall portion and one face of each of the first raised ribs facing toward the sidewall portion, and a second retaining portion is defined on another face of each of the first raised ribs facing away from the sidewall portion. 
     By providing the first and second retaining portions, a fan packed in the protective case can be more stably held in place, and the same protective case can be conveniently used to pack differently sized fans to save the cost of manufacturing differently sized protective cases. 
     The protective case for fan according to a second embodiment of the present invention includes a case body, a receiving space, and at least one set of two first raised ribs. The case body has a closed bottom portion and a sidewall portion connected to and extended along a periphery of the bottom portion. The receiving space is defined between the bottom portion and the sidewall portion, and has an open top portion opposite to the closed bottom portion. The two first raised ribs are formed on the closed bottom portion at a first set of two diagonally opposite corners thereof, and each of the first raised ribs includes a first and a second section located perpendicular to each other and adjacent to the sidewall portion, such that a first retaining portion is defined between the sidewall portion and one face of each of the first raised ribs facing toward the sidewall portion, and a second retaining portion is defined on another face of each of the first raised ribs facing away from the sidewall portion. By providing the first and second retaining portions, a fan packed in the protective case can be more stably held in place, and the same protective case can be conveniently used to pack differently sized fans to save the cost of manufacturing differently sized protective cases. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The structure and the technical means adopted by the present invention to achieve the above and other objects can be best understood by referring to the following detailed description of the preferred embodiments and the accompanying drawings, wherein 
         FIG. 1A  is an exploded perspective view showing a conventional protective case for packing a fan therein; 
         FIG. 1B  is an assembled view of  FIG. 1A ; 
         FIG. 2  is an exploded perspective view showing a protective case for fan according to a first preferred embodiment of the present invention with a first-size fan packed therein; 
         FIG. 3  is an assembled view of  FIG. 2 ; 
         FIG. 4  is a top view of  FIG. 3 ; 
         FIG. 5  is an exploded perspective view showing the protective case for fan according to the first preferred embodiment of the present invention with a second-size fan packed therein; 
         FIG. 6  is an assembled view of  FIG. 5 ; 
         FIG. 7  is a top view of  FIG. 6 ; 
         FIG. 8  is an exploded perspective view showing a protective case for fan according to a second preferred embodiment of the present invention with a first-size fan packed therein; 
         FIG. 9  is an assembled view of  FIG. 8 ; 
         FIG. 10  is a top view of  FIG. 9 ; 
         FIG. 11  is an exploded perspective view showing the protective case for fan according to the second preferred embodiment of the present invention with a second-size fan packed therein; 
         FIG. 12  is an assembled view of  FIG. 11 ; and 
         FIG. 13  is a top view of  FIG. 12 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     The present invention will now be described with some preferred embodiments thereof. For the purpose of easy to understand, elements that are the same in the preferred embodiments are denoted by the same reference numerals. 
     Please refer to  FIGS. 2 to 4  and  FIGS. 5 to 7 , in which a protective case for fan according to a first preferred embodiment of the present invention applicable to packing of two differently sized fans is shown. In the illustrated first preferred embodiment, the protective case for fan of the present invention includes a case body  2  and a case cover  3 . The case body  2  includes a closed bottom portion  21 , an open top portion  22 , and a sidewall portion  23  connected to and extended along a periphery of the bottom portion  21 . The closed bottom portion  21  and the sidewall portion  23  together define a receiving space  24  therebetween for accommodating a fan  5  therein, and the case cover  3  is closed onto the open top portion  22  of the case body  2  to seal the receiving space  24  and accordingly protects the fan  5  in the receiving space  24  against dust and foreign matters. 
     The closed bottom portion  21  is provided adjacent to a first set of two opposite sides with two first raised ribs  211 . That is, the two first raised ribs  211  are separately located at two opposite ends of the closed bottom portion  21 . Spaces left between the sidewall portion  23  and one face of the first raised ribs  211  facing toward the sidewall portion  23  are defined as two first retaining portions  25 , which are sized for engaging with two opposite lower edges of a fan frame  51  of a larger fan  5 , so that the faces of the first raised ribs  211  facing toward the sidewall portion  23  are abutted on inner faces of the fan frame  51  at the two opposite lower edges. More specifically, there are two first retaining portions  25  adapted to firmly hold two opposite lower sides of the fan frame  51  of a larger fan  5  therein. Meanwhile, another face of each of the first raised ribs  211  facing away from the sidewall portion  23  is defined as a second retaining portion  26 , which is adapted to firmly abut on an outer face of a fan frame  51  of a smaller fan  5 . That is, there are two second retaining portions  26  adapted to firmly abut on an outer face of the fan frame  51  of a smaller fan  5  at two opposite lower sides thereof. 
     The fan  5  can be generally divided into two types according to the size thereof, namely, a larger or first-size fan  52  being sized to 9 or 13 cm, and a smaller or second-size fan  53  being sized to 8 or 12 cm. Two opposite lower sides of the fan frame  51  of the first-size fan  52  can be correspondingly firmly engaged with and firmly held in the two first retaining portions  25 , as shown in  FIGS. 2 ,  3  and  4 . On the other hand, two opposite lower sides of the fan frame  51  of the second-size fan  53  can be correspondingly firmly abutted against the two second retaining portions  26 , as shown in  FIGS. 5 ,  6  and  7 . 
     The closed bottom portion  21  can be further provided adjacent to a second set of two opposite sides with two second raised ribs  212 . That is, the two second raised ribs  212  are separately located at another two opposite ends of the closed bottom portion  21 . Spaces left between the sidewall portion  23  and faces of the second raised ribs  212  facing toward the sidewall portion  23  are defined as two third retaining portions  27 , which are sized for engaging with another two opposite lower sides of the fan frame  51  of the larger fan  5 , so that faces of the second raised ribs  212  facing toward the sidewall portion  23  are abutted on an inner face of the fan frame  51  of the larger fan  5  at another two opposite lower sides thereof. More specifically, the larger fan  5 , that is, the first-size fan  52 , is held in place in the receiving space  24  of the case body  2  by the first and the third retaining portions  25 ,  27  at the same time. Meanwhile, another faces of the second raised ribs  212  facing away from the sidewall portion  23  are defined as two fourth retaining portions  28 , which are adapted to firmly abut on an outer face of the fan frame  51  of the smaller fan  5  at another two opposite lower sides thereof. Therefore, the smaller fan  5 , that is, the second-size fan  53 , is held in place in the receiving space  24  of the case body  2  by the second and the fourth retaining portions  26 ,  28  at the same time. More specifically, another two opposite lower sides of the fan frame  51  of the first-size fan  52  can be correspondingly firmly engaged with and firmly held in the two third retaining portions  27 ; on the other hand, another two opposite lower sides of the fan frame  51  of the second-size fan  53  can be correspondingly firmly abutted against the two fourth retaining portions  28 . 
     Also referring to  FIGS. 2 to 7 , the closed bottom portion  21  is further provided with a plurality of locating portions  214  and a receiving recess  217 . The receiving recess  217  is arranged between the two opposite first raised ribs  211  for receiving a central area of the fan frame  51  of the fan  5 . In other words, the receiving recess  217  is centered at the closed bottom portion  21  to locate between the two first raised ribs  211 . More specifically, the receiving recess  217  is located between the two first raised ribs  211  and between the two second raised ribs  212 . The locating portions  214  are angularly spaced along an outer periphery of the receiving recess  217  corresponding to a plurality of blades of the fan  5 , including the first-size and the second-size fan  52 ,  53 , so as to hold the blades in place in the case body  2 . 
     The locating portions  214  each have a curved configuration  215 , which includes a steep slope side  2151  and a gentle slope side  2152  that are located back to back. The gentle slope sides  2152  have a curvature matching that of the blades of the fan  5 , such that, when the fan  5  has been fully positioned in the case body  2 , the curved faces of the blades of the fan  5  bear on the gentle slope sides  2152  to effectively assist in stably holding the fan  5  in the case body  2 . A groove  216  is defined between the steep slope side  2151  and the gentle slope side  2152  that are separately located on any two adjacent locating portions  214  for correspondingly receiving an edge of the blade of the fan  5 . The grooves  216  are communicable with the receiving recess  217 . 
     In the receiving space  24 , there are further included limiting spaces  241  defined between an inner face of the sidewall portion  23  and corners of the closed bottom portion  21  for receiving corners of the fan frame  51 . The case cover  3  is closed onto the open top portion  22  of the case body  2  to seal the receiving space  24 , so as to effectively prevent dust or foreign matters from entering into the receiving space  24 . The case cover  3  is provided along a lower periphery with a downward extended flange portion  31  for correspondingly extending into the receiving space  24  to fitly abut on the inner face of the sidewall portion  23 . 
     Please refer to  FIGS. 2 to 7 . To pack the first-size fan  52  in the case body  2 , simply approach the first-size fan  52  toward the receiving space  24  of the case body  2 , so that the first-size fan  52  passes through the open top portion  22  to the closed bottom portion  21 . At this point, the lower sides of the fan frame  51  are engaged with the two first retaining portions  25  and the two third retaining portions  27  with the inner faces of the fan frame  51  at the lower sides thereof firmly abutting on the faces of the first and the second raised ribs  211 ,  212  facing toward the sidewall portion  23 . Meanwhile, the curved faces of the blades of the first-size fan  52  bear on the gentle slope sides  2152  of the curved configurations  215  of the locating portions  214 , preventing the blades from rotating in the receiving space  24  due to vibration or shaking, and the corners and the central area of the fan frame  51  of the first-size fan  52  are received in the limiting spaces  241  and the receiving recess  217 , respectively. Then, approaches the case cover  3  toward the case body  2  and closes the case cover  3  onto the open top portion  22 . At this point, the flange portion  31  of the case cover  3  is extended into the receiving space  24  to contact with the inner face of the sidewall portion  23 , and the first-size fan  52  is immovably sealed in the received space  24 . 
     Similarly, in the case of packing the second-size fan  53  in the case body  2 , simply approach the second-size fan  53  toward the receiving space  24  of the case body  2 , so that the second-size fan  53  passes through the open top portion  22  to the closed bottom portion  21 . At this point, the outer faces of the fan frame  51  at the lower sides thereof are abutted on the two second retaining portions  26  and the two fourth retaining portions  28  on the first and the second raised ribs  211 ,  212 . Meanwhile, the curved faces of the blades of the second-size fan  53  bear on the gentle slope sides  2152  of the curved configurations  215  of the locating portions  214 , preventing the blades from rotating in the receiving space  24  due to vibration or shaking, and the corners and the central area of the fan frame  51  of the second-size fan  53  are received in the limiting spaces  241  and the receiving recess  217 , respectively. Then, approaches the case cover  3  toward the case body  2  and closes the case cover  3  onto the open top portion  22 . At this point, the flange portion  31  of the case cover  3  is extended into the receiving space  24  to contact with the inner face of the sidewall portion  23 , and the second-size fan  53  is immovably sealed in the received space  24 . 
     Therefore, by providing the first and the second retaining portions  25 ,  26  on the closed bottom portion  21 , either the first-size fan  52  or the second-size fan  53  can be stably packed in the case body  2 . That is, the protective case according to the first preferred embodiment of the present invention has one size but can be used to pack two types of differently sized fans to thereby effectively save the time and labor needed to separately pack the fans  52  and  53  in two differently sized protective cases. Moreover, the one-size protective case for fan can be manufactured at reduced cost. 
     Please refer to  FIGS. 8 to 10  and  FIGS. 11 to 13 , in which a protective case for fan according to a second preferred embodiment of the present invention applicable to packing of two differently sized fans is shown. In the illustrated second preferred embodiment, the protective case for fan of the present invention includes a case body  2 , a receiving space  24 , at least one set of two first raised ribs  211 , and a case cover  3 . The case body  2  includes a closed bottom portion  21  and a sidewall portion  23  vertically connected to and extended along a periphery of the bottom portion  21 . The receiving space  24  is formed between the closed bottom portion  21  and the sidewall portion  23  for accommodating a fan  5  therein, and has an open top portion  22  opposite to the closed bottom portion  21 . The case cover  3  is closed onto the open top portion  22  to seal the receiving space  24  and accordingly protects the fan  5  in the receiving space  24  against dust and foreign matters. The two first raised ribs  211  are formed on the closed bottom portion  21  adjacent to a first set of two diagonally opposite corners thereof. Each of the first raised ribs  211  includes a first section  2111  and a second section  2112  extended closely along the sidewall portion  23 , and the second section  2112  is connected to the first section  2111  at a right angle. 
     Spaces left between the sidewall portion  23  and faces of the first raised ribs  211  facing toward the sidewall portion  23  are defined as two first retaining portions  25 , which are sized for engaging with two diagonally opposite lower corners of a fan frame  51  of a larger fan  5 , so that the faces of the first raised ribs  211  facing toward the sidewall portion  23  are abutted on inner faces of the fan frame  51  of the larger fan  5  at two diagonally opposite lower corners thereof. More specifically, there are two first retaining portions  25  adapted to firmly hold two diagonally opposite lower corners of the fan frame  51  therein. Meanwhile, another face of each of the first raised ribs  211  facing away from the sidewall portion  23  is defined as a second retaining portion  26 , which is adapted to firmly abut on an outer face of a fan frame  51  of a smaller fan  5 . That is, there are two second retaining portions  26  adapted to firmly abut on an outer face of the fan frame  51  of the smaller fan  5  at two diagonally opposite lower corners thereof. 
     The fan  5  can be generally divided into two types according to the size thereof, namely, a larger or first-size fan  52  being sized to 9 or 13 cm, and a smaller or second-size fan  53  being sized to 8 or 12 cm. Two diagonally opposite lower corners of the fan frame  51  of the first-size fan  52  can be correspondingly firmly engaged with and firmly held in the two first retaining portions  25 , as shown in  FIGS. 8 ,  9  and  10 . On the other hand, two diagonally opposite lower corners of the fan frame  51  of the second-size fan  53  can be correspondingly firmly abutted against the two second retaining portions  26 , as shown in  FIGS. 11 ,  12  and  13 . 
     The protective case for fan according to the second embodiment of the present invention can further include one set of two second raised ribs  212  formed on a second set of two diagonally opposite corners of the closed bottom portion  21 . Each of the second raised ribs  212  includes a third section  2121  and a fourth section  2122  extended closely along the sidewall portion  23 , and the fourth section  2122  is connected to the third section  2121  at a right angle. 
     Spaces left between the sidewall portion  23  and faces of the second raised ribs  212  facing toward the sidewall portion  23  are defined as two third retaining portions  27 , which are sized for engaging with another two diagonally opposite lower corners of the fan frame  51  of the larger fan  5 , so that the faces of the second raised ribs  212  facing toward the sidewall portion  23  are abutted on an inner face of the fan frame  51  of the larger fan  5  at another two diagonally opposite lower corners thereof. More specifically, the larger fan  5 , that is, the first-size fan  52 , is held in place in the receiving space  24  of the case body  2  by the first and the third retaining portions  25 ,  27  at the same time. Meanwhile, another faces of the second raised ribs  212  facing away from the sidewall portion  23  are defined as two fourth retaining portions  28 , which are adapted to firmly abut on an outer face of the fan frame  51  of the smaller fan  5  at another two diagonally opposite lower corners thereof. Therefore, the smaller fan  5 , that is, the second-size fan  52 , is held in place in the receiving space  24  of the case body  2  by the second and the fourth retaining portions  26 ,  28  at the same time. More specifically, another two diagonally opposite lower corners of the fan frame  51  of the first-size fan  52  can be correspondingly firmly engaged with and firmly held in the two third retaining portions  27 ; on the other hand, another two diagonally opposite lower corners of the fan frame  51  of the second-size fan  53  can be correspondingly firmly abutted against the two fourth retaining portions  28 . 
     Also referring to  FIGS. 8 to 13 , the closed bottom portion  21  is further provided with a plurality of locating portions  214  and a receiving recess  217 . The receiving recess  217  is arranged between the two diagonally opposite first raised ribs  211  for receiving a central area of the fan frame  51  of the fan  5 . In other words, the receiving recess  217  is centered at the closed bottom portion  21  to locate between the two first raised ribs  211 . More specifically, the receiving recess  217  is located between the two first raised ribs  211  and between the two second raised ribs  212 . The locating portions  214  are angularly spaced along an outer periphery of the receiving recess  217  corresponding to the blades of the fan  5 , including the first-size and the second-size fan  52 ,  53 , so as to hold the blades in place in the case body  2 . 
     The locating portions  214  each have a curved configuration  215 , which includes a steep slope side  2151  and a gentle slope side  2152  that are located back to back. The gentle slope sides  2152  have a curvature matching that of the blades of the fan  5 , such that, when the fan  5  has been fully positioned in the case body  2 , the curved faces of the blades of the fan  5  bear on the gentle slope sides  2152  to effectively assist in stably holding the fan  5  in the case body  2 . A groove  216  is defined between the steep slope side  2151  and the gentle slope side  2152  that are separately located on any two adjacent locating portions  214  for correspondingly receiving an edge of the blade of the fan  5 . The grooves  216  are communicable with the receiving recess  217 . 
     In the receiving space  24 , there are further included limiting spaces  241  defined between an inner face of the sidewall portion  23  and any two adjacent first and second raised ribs  211 ,  212  on the closed bottom portion  21  for receiving peripheral edges of the fan frame  51 . The case cover  3  is closed onto the open top portion  22  to seal the receiving space  24 , so as to effectively prevent dust or foreign matters from entering into the receiving space  24 . The case cover  3  is provided along a lower periphery with a downward extended flange portion  31  for correspondingly extending into the receiving space  24  to fitly abut on the inner face of the sidewall portion  23 . 
     Please refer to  FIGS. 8 to 13 . To pack the first-size fan  52  in the case body  2 , simply approach the first-size fan  52  toward the receiving space  24  of the case body  2 , so that the first-size fan  52  passes through the open top portion  22  to the closed bottom portion  21 . At this point, the lower corners of the fan frame  51  are engaged with the two first retaining portions  25  and the two third retaining portions  27  with the inner faces of the fan frame  51  at the lower corners thereof firmly abutting on the faces of the first and the second raised ribs  211 ,  212  facing toward the sidewall portion  23 . Meanwhile, the curved faces of the blades of the first-size fan  52  bear on the gentle slope sides  2152  of the curved configurations  215  of the locating portions  214 , preventing the blades from rotating in the receiving space  24  due to vibration or shaking, and the peripheral edges and the central area of the fan frame  51  of the first-size fan  52  are received in the limiting spaces  241  and the receiving recess  217 , respectively. Then, approaches the case cover  3  toward the receiving space  24  and closes the case cover  3  onto the open top portion  22 . At this point, the flange portion  31  of the case cover  3  is extended into the receiving space  24  to contact with the inner face of the sidewall portion  23 , and the first-size fan  52  is immovably sealed in the received space  24 . 
     Similarly, in the case of packing the second-size fan  53  in the case body  2 , simply approach the second-size fan  53  toward the receiving space  24  of the case body  2 , so that the second-size fan  53  passes through the open top portion  22  to the closed bottom portion  21 . At this point, the outer faces of the fan frame  51  at the lower corners thereof are abutted on the two second retaining portions  26  and the two fourth retaining portions  28  on the faces of the first and the second raised ribs  211 ,  212  facing away from the sidewall portion  23 . Meanwhile, the curved faces of the blades of the second-size fan  53  bear on the gentle slope sides  2152  of the curved configurations  215  of the locating portions  214 , preventing the blades from rotating in the receiving space  24  due to vibration or shaking, and the peripheral edges and the central area of the fan frame  51  of the second-size fan  53  are received in the limiting spaces  241  and the receiving recess  217 , respectively. Then, approaches the case cover  3  toward the receiving space  24  and closes the case cover  3  onto the open top portion  22 . At this point, the flange portion  31  of the case cover  3  is extended into the receiving space  24  to contact with the inner face of the sidewall portion  23 , and the second-size fan  53  is immovably sealed in the received space  24 . 
     In the present invention, the case body  2  can be made of a transparent or a translucent material, and a tab with a hanging hole can be extended from one side of the case body  2 , so that the protective case for fan is in the form of a hang card (not shown), and the fan  5  packed in the protective case can be hung on a display stand for sale. 
     Therefore, by providing the first and the second retaining portions  25 ,  26  on the closed bottom portion  21 , either the first-size fan  52  or the second-size fan  53  can be stably packed in the case body  2 . That is, the protective case according to the second preferred embodiment of the present invention has one size but can be used to pack two types of differently sized fans to thereby effectively save the time and labor needed to separately pack the fans  52  and  53  in two differently sized protective cases. Moreover, the one-size protective case for fan can be manufactured at reduced cost. 
     In brief, the protective case for fan according to the present invention has the following advantages: (1) enabling reduced manufacturing cost thereof; (2) providing enhanced locating effect to the fan packed in the protective case; (3) convenient for use; and (4) saving time and labor for packing the fan. 
     The present invention has been described with some preferred embodiments thereof and it is understood that many changes and modifications in the described embodiments can be carried out without departing from the scope and the spirit of the invention that is intended to be limited only by the appended claims.