Abstract:
The present invention is a closure apparatus of a wireless communication device having a heat-dissipating structure. The closure apparatus comprises: a first housing; and a second housing manufactured to be mechanically separated from the first housing and coupled to the first housing with preset spacing. The second housing includes equipment pre-selected based on the degree of heat dissipation from among multiple pieces of equipment of the communication device. The first housing includes equipment other than the equipment of the second housing.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is a continuation of International Application No. PCT/KR2012/006248 filed on Aug. 6, 2012. The application is incorporated herein by reference. 
     
    
     TECHNICAL FIELD 
       [0002]    The present invention relates to a box apparatus for a wireless communication device. 
       BACKGROUND ART 
       [0003]    As generally known in the art, various pieces of communication equipment are mounted in a box for a wireless communication device such as a base station of a wireless communication system, and include pieces of equipment, such as a radio frequency (RF) signal processing module, a high speed signal processing module, a power supply module, and a digital processing module, which generates a great amount of heat. 
         [0004]    Due to the heat generated while the equipment is operated at a maximum load, the temperature of the air in the box for a communication device, which contains the equipment, increases. If the temperature of the air in the box increases, the life span of the equipment is shortened by the heat and the function of the equipment deteriorates, and this also badly influences adjacent pieces of equipment and even causes a malfunction or a data processing error. 
         [0005]    Meanwhile, in the base station of the mobile communication system, the base station apparatuses are installed on the ground as compared with antenna apparatuses (generally, having a large volume and a heavy weight) installed at a column located high above the ground and the base station apparatuses are currently connected through cables. However, in recent years, as apparatuses have become lightweight and small-sized, the base station apparatuses are also installed in antenna installation columns at the same locations as that of the antenna apparatuses and a method of directly connecting the base station apparatuses to the antenna apparatuses are being applied. 
         [0006]    However, because various pieces of equipment are further densely installed in the base station apparatuses, heat emission and problems due to the heat emission become more important. Moreover, because a temperature rising factor of the box further increases due to waterproofing, moisture-proofing, anti-vibration rigging, and the like of the closing structure, a technology for promptly emitting the heat generated by the box to the outside of the box is required. 
         [0007]    A basic technology for increasing heat emission efficiency may include a measure of increasing heat emission areas of heat radiation fins including a plurality of heat radiation fins for the emission of heat. However, size and weight are increased by widening the heat emission area of the heat emission plate. This causes a difficulty in installation costs and installation work in the case of an outdoor communication device installed high above the ground, as well as manufacturing costs. 
       SUMMARY 
       [0008]    Accordingly, the present invention provides a box apparatus for a wireless communication device having a heat emission structure which enables more efficient heat emission. 
         [0009]    The present invention also provides a box apparatus for a wireless communication device which has a smaller size due to a better heat emission efficiency and has a heat emission structure for easily configuration and installation of the box apparatus. 
         [0010]    In accordance with an aspect of the present invention, there is provided a box apparatus for a wireless communication device having a heat emitting structure, the box apparatus including: a first housing; and a second housing manufactured to have a structure mechanically separated from the first housing and coupled to the first housing while being spaced apart from the first housing by a preset distance, wherein the second housing is provided with a piece of equipment selected in advance from a plurality of pieces of equipment of the communication device according to a degree of heat emission. 
         [0011]    Preferably, the piece of equipment provided in the second housing includes a high power amplification module. 
         [0012]    Preferably, a plurality of interval maintenance members are installed to maintain a preset interval between the first housing and the second housing when the first housing and the second housing are coupled to each other. 
         [0013]    Preferably, an auxiliary cover having a plurality of windows is installed between the first housing and the second housing to extend from side surface of the first housing and the second housing. 
         [0014]    Preferably, the first housing and the second housing are tightly closed to protect the pieces of equipment in the interiors of the first housing and the second housing. 
         [0015]    Preferably, signals are connected between the first housing and the second housing using a connector having a jack and a plug, and the plug is tilted with a resiliency. 
         [0016]    Preferably, the plug includes: a body substantially having a hollow cylindrical shape, having a large diameter portion having a large diameter at one side thereof and a small diameter portion having a small diameter at an opposite side thereof, and having a coupling portion extending from the large diameter portion such that the jack is coupled to the plug; a central conductor installed in an interior hollow of the body, for transmitting a signal; a fixing plate having a hole at the center thereof, the small diameter portion of the body being inserted through the hole, the diameter of the hole being larger than the diameter of the small diameter portion to have a preset margin and being smaller than the diameter of the large diameter portion, the fixing plate having a fixing hole for coupling to the outside through a fixing means; a fixing pin fixedly inserted through interference-fitting into a distal end of the small diameter portion protruding through the hole of the fixing plate while the small diameter portion of the body is inserted into the hole of the fixing plate and the size of which is set be larger than the diameter of the hole; a spring installed to surround the small diameter portion of the body, and one end of which is supported by a step formed at a border of the large diameter portion and the small diameter portion and an opposite end of which is supported by the fixing plate, for providing a restoring force for restoring the body to an original position when the body is moved; and a hollow housing formed to surround the coupling portion and the large diameter portion of the body, and a portion of the spring. 
         [0017]    Preferably, The box apparatus further includes a third housing manufactured to be mechanically separated from the first housing and coupled to the first housing to be spaced from the first housing by a preset distance, wherein the third housing is provided with a piece of equipment selected in advance from a plurality of pieces of equipment of the communication device according to a degree of heat emission, in addition to the piece of equipment provided in the second housing. 
         [0018]    Preferably, the second housing and the third housing are located on opposite sides of the first housing with respect to an installation state of the body apparatus. 
         [0019]    Preferably, the pieces of equipment provided in the second housing and the third housing include high power amplification modules. 
         [0020]    Preferably, the first housing and the second housing, and the first housing and the third housing have through-holes on facing surfaces thereof, protrusions extend from outer surfaces of the first housing on which the holes are formed toward the second housing and the third housing or from outer surfaces of the second housing and the third housing on which the holes are formed toward the first housing, and a signal is connected between the housings by a cable connected through the holes. 
         [0021]    Preferably, a plurality of heat radiation fins for heat emission are formed in the second housing and the third housing, and are formed lengthily in the convection direction with respect to the installation state of the box apparatus. 
         [0022]    Accordingly, the box apparatus for a wireless communication device having a heat emission structure according to the present invention has excellent heat emission efficiency, can be miniaturized, and can be easily manufactured and installed. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0023]      FIG. 1  is an exploded perspective view of a box apparatus for a wireless communication device having a heat emission structure according to a first embodiment of the present invention; 
           [0024]      FIG. 2  is a front view showing a coupled state of  FIG. 1 ; 
           [0025]      FIG. 3  is a cutaway sectional view taken along line A-A′ of  FIG. 1 ; 
           [0026]      FIG. 4  is a perspective view of a plug and a jack of a connector of  FIG. 1 ; 
           [0027]      FIG. 5  is an exploded perspective view of the plug of  FIG. 4 ; 
           [0028]      FIG. 6  is a sectional view of the plug of  FIG. 4 , which is taken along line A-A; 
           [0029]      FIG. 7  is a view showing an in-use state of the plug shown in  FIGS. 4 to 6 ; 
           [0030]      FIG. 8  is an exploded perspective view of a box apparatus for a wireless communication device having a heat emission structure according to a second embodiment of the present invention; and 
           [0031]      FIG. 9  is a cutaway sectional view taken along line A-A′ of  FIG. 8 . 
       
    
    
     DETAILED DESCRIPTION 
       [0032]    Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. 
         [0033]      FIG. 1  is an exploded perspective view of a box apparatus for a wireless communication device having a heat emission structure according to a first embodiment of the present invention.  FIG. 2  is a front view showing a coupled state of  FIG. 1 .  FIG. 3  is a cutaway sectional view taken along line A-A′ of  FIG. 1 . 
         [0034]    Referring to  FIGS. 1 to 3 , the box apparatus for a wireless communication device according to the first embodiment of the present invention includes: a first housing  20 ; a second housing  40  manufactured to have a structure mechanically separated from the first housing  20  and coupled to the first housing  20  while being spaced apart from the first housing  20  by a preset distance. 
         [0035]    The first housing  20  is provided with the most pieces of equipment of the wireless communication device, such as a radio frequency (RF) signal processing module, a high speed signal processing module, a power supply module, and a digital processing module, for example, when the corresponding wireless communication device is a base station apparatus, and the second housing  40  is provided with a preselected piece of equipment, for example, a high power amplification module, which generates a large amount of heat among several pieces of equipment of the corresponding wireless communication device. 
         [0036]    A plurality of interval maintenance members  50  inserted between the first housing  20  and the second housing  40  when the first housing  20  and the second housing  40  are coupled to each other to maintain a preset distance between the first housing  20  and the second housing  40 . The first housing  20  and the second housing  40  may be coupled to each other by a plurality of screws  52 , and holes for the screws  52  are formed in the plurality of interval maintenance members  50 . The plurality of screws  52  are coupled to holes formed in the second housing  40  at a lower side (in the drawings) of the second housing  40  and screw holes formed at locations corresponding to the holes of the first housing  20  through the holes formed in the interval maintenance member  50  to fixedly attach the first housing  20  and the second housing  40 . 
         [0037]    In this way, because the first housing  20  and the second housing  40  are coupled to each other to be spaced apart from each other at a preset distance, an air layer  32  is formed between the first housing  20  and the second housing  40 . An auxiliary cover  30  is further installed at an outer edge of the air layer  32 , that is, in a shape extending in a mutual direction from the first housing  20  and the second housing  40  to provide an appealing external appearance and an additional support force. The auxiliary cover  30  may be formed of a material which does not allow easy heat transfer, for example, a plastic material. Ventilation or convection for emission of heat may be smoothly made by a window  302  of the auxiliary cover  30 . 
         [0038]    As described above, the communication device according to the present invention, to which the first housing  20  and the second housing  40  are coupled, may be then directly or indirectly attached to an antenna apparatus  10  or may be attached for antenna installation column using a separate bracket apparatus. 
         [0039]    It can be seen that the above-configured box apparatus for a communication device according to the first embodiment of the present invention individually separates only pieces of equipment which generate the most heat among several pieces of equipment of the corresponding communication device and installs them in the second housing  40 , which is a separate housing. 
         [0040]    For example, when the corresponding communication device is a base station apparatus, in particular, as shown in  FIG. 4 , the first housing  20  and the second housing  40  are separately manufactured in a manner the second housing  40  is tightly closed by a second housing cover  42  after a substrate  410  of a high power amplification module is installed within the second housing  40  and the first housing  20  is tightly closed by a first housing cover  22  after substrates  210  of the other pieces of equipment are installed within the first housing  20 . In the base station apparatus, heat corresponding to about ⅔ of an entire heating value may be generated even only the substrate  410  of the high power amplification module. 
         [0041]    Accordingly, the present invention can intensively apply a heat emission structure to equipment having high heat emission together with a plurality of heat radiation fins  402  for heat emission formed outside the second housing  20 , thereby improving heat emission efficiency. Moreover, because the first housing  20  and the second housing  40  are separately formed and coupled to be spaced apart from each other such that the air layer is formed between the first housing  20  and the second housing  40 , heat generated from the heat emitting equipment provided in the second housing  40  does not influence the first housing  20 . Accordingly, heat does not badly influence several pieces of equipment provided in the first housing  20 . 
         [0042]    Meanwhile, a signal connection method of the first housing  20  and the second housing  40  may employ a general method using a cable and a connector, but an improved snap-on type connector is used in the first embodiment of the present invention. 
         [0043]    In general, the connector may be classified into a coupling nut type and a snap-on type according to a coupling method, and a coupling nut type connector has a structure in which a plug having an outer peripheral surface on which a nut is mounted and a jack having a male screw on an outer peripheral surface thereof, such that the male screw is coupled to the nut are screw-coupled to each other. The snap-on type connector has a structure in which a boss formed at one end of a body of a plug and a recess formed in an interior of a body of a jack and into which a boss may be inserted are coupled to each other in an insertion method. 
         [0044]    Then, in the case of the snap-on method, because a plug and a jack are simply coupled to each other through an insertion method, they may be promptly coupled to each other. 
         [0045]    As shown in  FIGS. 1 to 3 , the first housing  20  and the second housing  40  may be connected to each other for connection of signals using a snap-on type connector, and for example, a plurality of plugs  70  may be provided in the first housing  20  and a plurality of jacks  60  may be provided in the second housing  40  at locations corresponding to the plugs  70 . 
         [0046]    Because the plurality of plugs  70  and the plurality of jacks  60  are fitted with each other when the first housing  20  and the second housing  40  are fixed to each other, the plurality of plugs  70  and the jacks  60  are connected to each other. 
         [0047]    However, when the plugs  70  and the jacks  60  are misaligned due to the manufacturing tolerances of the plugs  70  and the jacks  60 , they may not be normally coupled to each other. Moreover, when a plurality of connectors are arranged, the problem may become severe. 
         [0048]    Accordingly, the first embodiment of the present invention provides a snap-on type connector having an improved structure such that the plugs  70  and the jacks  60  may be normally engaged with each other while some manufacturing tolerances are allowed. 
         [0049]      FIG. 4  is a perspective view of the plug  70  and the jack  60  of the snap-on type connector of  FIG. 1 .  FIG. 5  is an exploded perspective view of the plug  70  of  FIG. 4 .  FIG. 6  is a sectional view of the plug  70  of  FIG. 4 , which is taken along line A-A.  FIG. 7  is a view showing an in-use state of the plug  70  shown in  FIGS. 4 to 6 . 
         [0050]    Referring to  FIGS. 4 to 7 , the connector according to the first embodiment of the present invention includes a jack  60  acting as a bolt, and a plug  70  accommodating the jack  60  therein. 
         [0051]    The plug  70  has a substantially hollow cylindrical shape, and has a body  720  having a large diameter portion  726  of a large diameter at one side thereof and having small diameter portions  722  and  723  of small diameters at an opposite side thereof. Then, the small diameter portions  722  and  723  may be classified into a first small diameter portion  723  and a second small diameter portion  722  in an extension direction of the large diameter portion  726 , and then the second small diameter portion  722  may have the smallest diameter. 
         [0052]    The body  720  has a coupling portion  721  extending from the large diameter portion  726  and to which the jack  60  will be coupled, and a central conductor  730  for transmitting a signal is installed in an interior hollow of the body  720 . 
         [0053]    The body  720  is fixed by a fixing plate  750 , a fixing pin  760 , and a spring  740 , and first, the fixing plate  750  has a plate shape having a hole  752  at the center thereof and the small diameter portions  722  and  723  of the body  720  are inserted into the hole  750  to pass through the hole  752 . Then, the diameter of the hole  752  is large enough to have a preset margin as compared with the diameters of the small diameter portions  722  and  723 , and is smaller than the diameter of the large diameter portion  726 . 
         [0054]    A plurality of fixing holes  752  into which fixing means (not shown) such as screws are inserted to be coupled to the fixing holes  752  are formed in the fixing plate  750  such that the fixing plate  750  is fixed to an external substrate or the like. 
         [0055]    In the state in which the small diameter portions  722  and the  723  of the body  720  are inserted into the hole  752  of the fixing plate  750 , the fixing pin  760  is fixedly interference-fitted with the small diameter portions  722  and  723  protruding through the hole  752  of the fixing plate  750 , that is, with the second small diameter portion  722  with a structure formed in advance to be engaged with the fixing pin  760 , in which case the size of the fixing pin  760  is set to be larger than the diameter of the hole  752  such that the small diameter portions  722  and  723  from being separated from the hole  752 . 
         [0056]    The first diameter portion  723  of the body  720  is installed to be surrounded by the cylindrical spring  740 , and provides a restoring force for restoring the body  720  to an original position when one end of the spring  740  is supported by a step  725  formed at a border of the large diameter portion  726  and the first small diameter portion  723  and an opposite end of the spring  740  is supported by the fixing plate  750  such that the body  720  is moved, that is, when the body  720  is moved forwards and rearwards (vertically in the drawing) and is inclined upwards, downwards, leftwards, and rightwards (horizontally in the drawing). 
         [0057]    A hollow housing  10  formed to surround the coupling portion  721 , the large diameter portion  726 , and a portion of the cylindrical spring  740  of the body  720  may be installed in the body  720 , for example, interference-fitted with the body  720 . 
         [0058]    In this state, the small diameter portions  722  and  723  of the body  720  of the plug  70  are located in the hole  751  of the fixing plate  750 , in which case because the outer diameters of the small diameter portions  722  and  723  are smaller than the inner diameter of the hole  751  of the fixing plate  750 , the body  720  may move forwards, rearwards, upwards, downwards, leftwards, and rightwards from the fixing plate  750  to a degree as shown in  FIG. 4 . 
         [0059]    In this way, because the body  720  may be moved forwards and rearwards and inclined upwards, downwards, leftwards, and rightwards to a degree while the plug  70  of the connector is fixed to the substrate, the cover or the like, the plug  70  and the jack  60  may be smoothly connected to each other even though the jack  60  fitted with the plug  70  is installed at a location having some errors. 
         [0060]    Due to the connector, the box apparatus according to the embodiment of the present invention may have an integral external appearance. As described above, the box apparatus according to the embodiment of the present invention separately includes a first box and a second box, but the first box and the second box are electrically connected to each other and an auxiliary cover is provided between the first box and the second box so that an external appearance of the box apparatus may seem to be integral. 
         [0061]      FIG. 8  is an exploded perspective view of a box apparatus for a wireless communication device having a heat emission structure according to a second embodiment of the present invention.  FIG. 9  is a cutaway sectional view taken along line A-A′ of  FIG. 8 . The second embodiment of the present invention shown in  FIGS. 8 and 9  has a structure similar to that of the first embodiment of the present invention shown in  FIGS. 1 to 3 , and the constituent elements for performing similar functions are given the same reference numerals. 
         [0062]    Referring to  FIGS. 8 to 9 , similarly to the configuration of the first embodiment shown in  FIGS. 1 to 3 , the box apparatus for a wireless communication device according to the second embodiment of the present invention includes: a first housing  20 ; a second housing  40  manufactured to have a structure mechanically separated from the first housing  20  and coupled to the first housing  20  while being spaced apart from the first housing  20  by a preset distance. Meanwhile, in addition to the configuration, the second embodiment of the present invention further includes a third housing  80  manufactured to have a structure mechanically separated from the first housing  20  and coupled to the first housing  20  while being spaced apart from the first housing  20  by a preset distance like the second housing  40 . 
         [0063]    That is, in the second embodiment of the present invention, the second housing  40  and the third housing  80  are located on the left and right side surfaces of the first housing  30 , that is, opposite sides of the first housing  30  with respect to the installation state of the box apparatus, that is, with respect to the installation location of the antenna apparatus  10 , so as to be coupled to each other. 
         [0064]    The first housing  20  is provided with most pieces of equipment of the wireless communication device, such as a radio frequency (RF) signal processing module, a high speed signal processing module, a power supply module, and a digital processing module, for example, when the corresponding wireless communication device is a base station apparatus, and the second housing  40  and the third housing  80  are provided with a preselected piece of equipment, for example, a high power amplification module, which generates a large amount of heat among several pieces of equipment of the corresponding wireless communication device. 
         [0065]    That is, the high power amplification module may include a plurality of high power amplification elements, and some elements may be provided in the second housing  40 , and the remaining ones may be provided in the third housing  80 . The second housing  40  may include equipment selected because it generates heat most, and the third housing  80  may include equipment selected because it generates heat the second most. 
         [0066]    It can be seen that as compared with the first embodiment of the present invention, in the box apparatus for a communication device according to the second embodiment of the present invention, several pieces of equipment are distributed in the second housing  20  and the third housing  80 , so that heat emission efficiency can be further increased. 
         [0067]    Meanwhile, one or more holes  23  are formed on surfaces of the first housing facing the second housing  40  and the third housing  80 , and protrusions  50 ′ protruding and extending toward the second and third housings  40  and  80  are provided around the holes  23 . That is, the first housing  20  and the second and third housings  40  and  80  may be spaced apart from each other by a predetermined distance due to the protrusions  50 ′, and heat may be radiated through the spaces through convection. 
         [0068]    Although it has been exemplified in the embodiment of the present invention that the protrusions  50 ′ are integrally formed with the first housing  20 , a separate tubular member may be attached or screw-coupled to the first housing  20 . 
         [0069]    Ends of the tubular protrusions  50 ′ facing the first and second housings  40  and  80  have screw recesses  501  to which a plurality of screws  52  may be coupled, and through-holes  401  through which the screws  52  may pass are formed in the second housing  40  and the third housing  80 . The plurality of screws  52  are coupled to the screw recesses  501  formed in the interval maintenance members  50  on outer surfaces of the second housing  40  and the third housing  80  through the through-holes formed in the second housing  40  and the third housing  80 , so that the first housing  20  and the second housing  40 , and the first housing  20  and the third housing  80  may be fixedly attached to each other. 
         [0070]    Then, although signal connection schemes between the first housing  20  and the second housing  40 , and the first housing  20  and the third housing  80  may employ a method of using a snap-on type connector according to the first embodiment of the present invention shown in  FIGS. 1 to 7 , a method of using a general cable  90  is used in the second embodiment of the present invention. That is, interior spaces of the tubular protrusions  50 ′ are used as passages for a cable. One end of the cable  90  is connected to a substrate  210  of the internal equipment of the first housing  20  through the interior space of the tubular protrusion  50 ′ and an opposite end of the cable  90  is connected to a substrate  410  of the internal equipment of the second housing  40  (or the third housing), so that a signal is connected between (the pieces of internal equipment of) the separated housings with a simpler structure. Of course, holes  43  through which the cable  90  passes are formed at locations of the second housing  40  and the third housing  80  corresponding to the interior spaces of the tubular protrusions  50 ′, and the other parts are tightly closed. 
         [0071]    Meanwhile, in the second embodiment of the present invention, a plurality of heat radiation fins  402  for heat emission are formed in the second housing  40  and the third housing  80  and a plurality of heat radiation fins  202  are formed in the first housing  20 , and because the heat radiation fins  402  and  202  are formed lengthily with respect to the installation state of the box apparatus, heat radiation efficiency can be increased by smoothly circulating air through convection. 
         [0072]    The box apparatus for a wireless communication device having the heat emission structures according to the embodiments of the present invention may be configured in this way, and the detailed embodiments of the present invention have been described, various modifications can be made without departing from the scope of the present invention. 
         [0073]    For example, although it has been described in the first embodiment shown in  FIGS. 1 to 3  that an auxiliary cover  30  is installed between the first housing  20  and the second housing  30 , the auxiliary cover  30  may not be provided according to occasions and the form and material of the auxiliary cover  30  may be variously designed. 
         [0074]    Further, in the first embodiment of the present invention shown in  FIGS. 1 to 3 , a plurality of heat radiation fins  402  for heat emission are formed in the second housing  40  but a plurality of heat radiation fins also may be provided in the first housing  20 . 
         [0075]    When the box apparatus for a communication device according to the present invention in which the first housing  20  and the second housing  40  are coupled to each other is coupled to the antenna apparatus  10 , the connector structure for transmission of signals may employ the snap-on type connector according to the first embodiment of the present invention shown in  FIGS. 4 to 7 . 
         [0076]    In the first embodiment of the present invention shown in  FIGS. 4 to 7 , the fixing pin  760  of the connector has an E shape in which a disk plate shape is partially removed from the center to an outer peripheral surface thereof, and the partially removed and opened portion is fixedly inserted into the second small diameter portion  722  of the body  720  through interference-fitting, and the second small diameter portion  722  has a structure having a positioning recess  724  in which the fixing pin  760  is inserted and positioned. 
         [0077]    However, in addition to the configuration, the fixing pin  760  may simply have a clip or bar shape, and the second small diameter portion  722  may have a recess or hole into which the fixing pin  760  is inserted. 
         [0078]    Although it has been described in the second embodiment of the present invention shown in  FIGS. 8 and 9  that the second housing  40  and the third housing  80  are installed on the left and right side surfaces of the first housing  20 , any one of the second housing  40  and the third housing  80  may be installed on a front surface or a rear surface of the first housing  20  to occupy a partial range or an entire range thereof. In addition, one or more separate housings may be further provided together with the second housing  40  and the third housing  80  to be installed on a front surface, a rear surface, or a bottom surface of the first housing  20 . 
         [0079]    Although it has been described in the second embodiment of the present invention shown in  FIGS. 8 and 9  that the tubular protrusions  50 ′ are integrally fixed to the first housing  20 , the tubular protrusions may be integrally fixed to the second housing  40  and the third housing  80 . In this case, through-holes through which screws pass through may be formed in the tubular interval maintenance members, and screw recesses to which screws are coupled may be formed at corresponding locations of the first housing.