Abstract:
A heat sink includes: a fixing unit fixed to a heating element; and a heat dissipation unit including a heat dissipation protruding portion and configured to slide with respect to the fixing unit.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application is based upon and claims the benefit of priority from the prior Japanese Patent Application No. 2013-179771 filed on Aug. 30, 2013, the entire contents of which are incorporated herein by reference. 
       FIELD 
       [0002]    The present disclosure relates to a heat sink and a substrate unit. 
       BACKGROUND 
       [0003]    A heat sink includes a fixing unit fixed to a heating element, and heat dissipation protruding portions formed integrally with the fixing unit. 
         [0004]    A related technology is disclosed in Japanese Laid-Open Patent Publication Nos. 2010-219250, 2010-263118 and 2007-188998. 
       SUMMARY 
       [0005]    According to one aspect of the embodiments, a heat sink includes: a fixing unit fixed to a heating element; and a heat dissipation unit including a heat dissipation protruding portion and configured to slide with respect to the fixing unit. 
         [0006]    The object and advantages of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the claims. It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory and are not restrictive of the invention, as claimed. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0007]      FIG. 1  illustrates an exemplary side cross-sectional view of a substrate unit. 
           [0008]      FIG. 2  illustrates an exemplary position change of a heat dissipation unit. 
           [0009]      FIG. 3  illustrates an exemplary exploded perspective view of a heat sink. 
           [0010]      FIG. 4  illustrates an exemplary cross-sectional view taken along a line  4 - 4  of the heat sink. 
           [0011]      FIG. 5  illustrates an exemplary position change of a heat dissipation unit. 
           [0012]      FIG. 6  illustrates an exemplary heat sink. 
           [0013]      FIG. 7  illustrates an exemplary cross-sectional view of a heat sink. 
           [0014]      FIG. 8  illustrates an exemplary perspective view of a heat sink. 
           [0015]      FIG. 9  illustrates an exemplary side cross-sectional view of a substrate unit. 
           [0016]      FIG. 10  illustrates an exemplary position change of an electronic component. 
       
    
    
     DESCRIPTION OF EMBODIMENTS 
       [0017]    In a technology of cooling a heating element by using a heat sink, a restriction may be imposed on placement of a heating element such as an electronic component with respect to a heat sink, for example, when the heating element is disposed at a desired position on a printed circuit board. 
         [0018]      FIG. 1  illustrates an exemplary side cross-sectional view of a substrate unit. The substrate unit  10  illustrated in  FIG. 1  includes a printed circuit board  12 , a plurality of electronic components  14  and  16 , and a plurality of heat sinks  18  and  20 . The electronic component  14  may also be referred to as a first electronic component  14 , and the electronic component  16  may also be referred to as a second electronic component  16 . 
         [0019]    The printed circuit board  12  is formed in a flat plate shape. Each of the first and second electronic components  14  and  16  is mounted on the surface of the printed circuit board  12  by, for example, soldering. The first and second electronic components  14  and  16  may be, for example, heating components such as a central processing unit (CPU), and may be aligned in the X direction when the printed circuit board  12  extends in the X direction and the Y direction. 
         [0020]    The first and second electronic components  14  and  16  are coupled to each other through a wiring (e.g., conductive pattern) formed on the surface of the printed circuit board  12  so that transmission and reception of signals are performed between the first electronic component  14  and the second electronic component  16 . For example, the first electronic component  14  at one side may be a first heating element, and the second electronic component  16  at the other side may be a second heating element. 
         [0021]    Both of the heat sinks  18  and  20  are made of a metallic material such as an aluminum alloy which is excellent in heat dissipation and thermal conductivity. The heat sink  18  at one side may be an exemplary first heat sink (hereinafter, the heat sink  18  may also be referred to as a first heat sink  18 ), and includes a plate-shaped fixing unit  22 , and a plurality of fins  24  vertically provided on the surface of the fixing unit  22 . Each of the fins  24  is formed in a plate shape which has a plate thickness in the Y direction and extends in the X direction. The plurality of fins  24  are arranged in the Y direction to be spaced apart from each other, in the same manner as a plurality of fins  56  (See, e.g.,  FIG. 2 ) provided on the heat sink  20  at the other side. 
         [0022]    The fixing unit  22  is superimposed on the surface of the first electronic component  14  through a heat transfer sheet  26 . Stepped screws  28  penetrate portions of the fixing unit  22  at both sides of the first electronic component  14 , respectively. A threaded portion  30  formed on the end portion of each stepped screw  28  penetrates the printed circuit board  12  from the front side of the printed circuit board  12 , and a nut  32  is screwed on the end portion of the threaded portion  30  from the rear side of the printed circuit board  12 . 
         [0023]    A coil spring  34  is fitted on the stepped screw  28 , and is interposed between a head portion  36  of the stepped screw  28  and the fixing unit  22  in a compressed state. The fixing unit  22  is forcedly pressed toward the side of the first electronic component  14  by the coil spring  34 . In a state where the fixing unit  22  is forcedly pressed toward the side of the first electronic component  14 , the first heat sink  18  is fixed to the first electronic component  14 . 
         [0024]    An extension portion  38  is formed at the end portion of the fixing unit  22  of the first heat sink  18  on the side of the second electronic component  16 . The extension portion  38  may be formed by extending the end portion of the fixing unit  22  on the side of the second electronic component  16  along the X direction to the side of the second electronic component  16 . A plurality of fins  40  similar to the plurality of fins  24  are vertically provided on the surface of the extension portion  38 . 
         [0025]    The other heat sink  20  may be an exemplary second heat sink, and includes a fixing unit  42 , and a heat dissipation unit  44  (hereinafter, the other heat sink  20  may also be referred to as a second heat sink  20 ). The fixing unit  42  and the heat dissipation unit  44  may be separate members. The fixing unit  42  is formed in a plate shape, and is superimposed on the surface of the second electronic component  16  through a heat transfer sheet  46 . Leg portions  48  are formed on the fixing unit  42  at both sides of the second electronic component  16 , respectively, to extend toward the printed circuit board  12 . Each leg portion  48  is in contact with the surface of the printed circuit board  12  and is vertically provided on the printed circuit board  12 . 
         [0026]    A screw  50  penetrates the leg portion  48  positioned on the side of the first electronic component  14  and a portion of the printed circuit board  12  corresponding to the leg portion  48 , from the front side of the fixing unit  42 . A nut  52  is screwed on the end portion of the screw  50  from the rear side of the printed circuit board  12 . The fixing unit  42  is fixed to the second electronic component  16  by the screw  50 . 
         [0027]    The heat dissipation unit  44  includes a main body  54  having a plate shape superimposed on the surface of the fixing unit  42 , and a plurality of fins  56  vertically provided on the surface of the main body  54  (on the surface at a side opposite to the fixing unit  42 ).  FIG. 2  illustrates an exemplary position change of a heat dissipation unit.  FIG. 2  illustrates the states of the heat dissipation unit of the heat sink illustrated in  FIG. 1  before and after the position thereof is changed by perspective views.  FIG. 3  illustrates an exemplary heat sink.  FIG. 3  illustrates an exploded perspective view of the heat sink illustrated in  FIG. 2 .  FIG. 4  illustrates an exemplary cross-sectional view of the heat sink.  FIG. 4  illustrates a cross-sectional view taken along a line  4 - 4  of the heat sink  20  illustrated in  FIG. 2 . As illustrated in  FIGS. 2 and 3 , the main body  54  includes a pair of arm portions  58  which extend in the X direction and are arranged in parallel to each other in the Y direction, and a connection portion  60  which extends in the Y direction to interconnect one ends of the pair of arm portions  58 . 
         [0028]    Each of the fins  56  is formed in a plate shape which has a plate thickness in the Y direction and extends in the X direction. The plurality of fins  56  are arranged in the Y direction to be spaced apart from each other. The plurality of fins  56  may be exemplary heat dissipation protruding portions, and may be provided on the connection portion  60  of the main body  54 . For example, as illustrated in  FIG. 1 , the plurality of fins  56  are provided on the main body  54  at a side opposite to the extension portion  38  side which is at one side in the X direction. 
         [0029]    As illustrated in  FIG. 3 , a pair of grooves  62  are formed in the fixing unit  42  to be opened on the surfaces of the fixing unit  42 . The pair of grooves  62  extend in the X direction and are formed in the fixing unit  42  at both end portions in the Y direction. One end of each of the grooves  62  is terminated, and the other end of each of the grooves  62  is opened in the X direction of the fixing unit  42 . The X direction where the pair of grooves  62  extend may intersect the Z direction where the fixing unit  42  is superimposed on the second electronic component  16  (see  FIG. 1 ). 
         [0030]    A pair of projecting portions  64  are formed on the rear surface of the heat dissipation unit  44  to protrude toward the fixing unit  42 . The pair of projecting portions  64  are formed at positions corresponding to the pair of grooves  62 , respectively, and extend in the X direction, respectively, like the pair of grooves  62 . 
         [0031]    The pair of projecting portions  64  are inserted into the pair of grooves  62  form the other end sides of the pair of grooves  62 . Each groove  62  and each projecting portion  64  are formed in tapered shapes in which the width of the Y direction is decreased from the bottom side of the groove  62  to the opening side of the groove  62 . This suppresses the projecting portion  64  from being released from the groove  62 . When the pair of projecting portions  64  are inserted into the pair of grooves  62 , the heat dissipation unit  44  is slidable in the X direction with respect to the fixing unit  42 . As illustrated in  FIG. 1 , for example, the sliding direction of the heat dissipation unit  44  may correspond to the extension direction of the extension portion  38 . 
         [0032]    In a state where the second heat sink  20  and the first heat sink  18  are aligned in the X direction, the extension portion  38  of the first heat sink  18  covers a part of the fixing unit  42  of the second heat sink  20 . For example, the extension portion  38  is positioned at a higher position than the fixing unit  42  in the height direction of the heat sink  20  (in the Z direction), while overlapping with a part of the fixing unit  42  on the side of the first electronic component  14  in the X direction. 
         [0033]    The extension portion  38  is positioned at a higher position than the main body  54  in the height direction of the heat sink  20 . The heat dissipation unit  44  may be slid to the opposite side to the side of the extension portion  38  so as to avoid for the fins  56  of the heat dissipation unit  44  interfering with the extension portion  38 . Accordingly, the fins  56  are disposed to be offset from the second electronic component  16  in the X direction which is the sliding direction of the heat dissipation unit  44 . 
         [0034]    Even though the extension portion  38  is formed in the heat sink  18  illustrated in  FIG. 1 , the positions of the first electronic component  14  and the second electronic component  16  are unchanged, and only the position of the heat dissipation unit  44  is moved to the opposite side to the side of the first electronic component  14 . A moving mechanism is provided to correspond to the addition of the extension portion  38 . 
         [0035]    A heat transfer material such as, a thermal grease, may be interposed between the heat dissipation unit  44  and the fixing unit  42  so as to facilitate heat transfer. 
         [0036]    In the substrate unit illustrated in  FIG. 1 , the heat dissipation unit  44  is slid with respect to the fixing unit  42 . Even though the extension portion  38  which extends to the side of the second electronic component  16  is formed in the heat sink  18  to improve the heat dissipation, the heat dissipation unit  44  is slid with respect to the fixing unit  42  to the side opposite to the extension portion  38 . Therefore, the interference of the extension portion  38  with the fins  56  of the heat dissipation unit  44  may be reduced. The placement restriction imposed on the second electronic component  16  may be decreased so that the second electronic component  16  may be disposed close to the first electronic component  14 . 
         [0037]    For example, when the heat sink  20  is formed as an integrated structure, together with the fixing unit  42  and the heat dissipation unit  44 , the entire heat sink  20  including the heat dissipation unit  44  may be separated from the extension portion  38  so as to reduce the interference between the extension portion  38  extending from the heat sink  18  and the fins  56  of the heat dissipation unit  44 . In this case, in order to secure the cooling property of the second electronic component  16 , the second electronic component  16  may be disposed just below the second heat sink  20 . For example, when the heat sink  20  is formed as an integrated structure, together with the fixing unit  42  and the heat dissipation unit  44 , a placement restriction may be imposed on the second electronic component  16  since the second electronic component  16  is not disposed close to the first electronic component  14 . 
         [0038]    For example, when the heat dissipation unit  44  is slid with respect to the fixing unit  42  to the side opposite to the extension portion  38 , the second electronic component  16  may be disposed close to the first electronic component  14 . 
         [0039]    When the first electronic component  14  is disposed close to the second electronic component  16 , the length of wiring that interconnects the first electronic component  14  and the second electronic component  16  is reduced. Therefore, the transmission rate of a signal between the first electronic component  14  and the second electronic component  16  may be improved. Since the space below the extension portion  38  is effectively utilized for disposition of the second electronic component  16 , the mounting density of the printed circuit board  12  may be improved. 
         [0040]    The main body  54  of the heat dissipation unit  44  is superimposed on the fixing unit  42 . Accordingly, the contact area between the fixing unit  42  and the heat dissipation unit  44  may be secured such that the thermal conductivity may be secured between the fixing unit  42  and the heat dissipation unit  44 . Even when the heat dissipation unit  44  is slid with respect to the fixing unit  42 , the heat dissipation of the heat sink  20  may be secured. 
         [0041]    As illustrated in  FIG. 2 , the pair of grooves  62  extending in the X direction are formed in the fixing unit  42  and the projecting portions  64  inserted into the pair of grooves  62  are formed on the heat dissipation unit  44 . Accordingly, the sliding direction of the heat dissipation unit  44  with respect to the fixing unit  42  is defined by the pair of grooves  62  and the projecting portions  64 . Therefore, the operability when the heat dissipation unit  44  is slid, for example, the usability of the heat sink  20  may be improved. 
         [0042]    As illustrated in  FIG. 1 , the leg portions  48  are formed on the fixing unit  42  to be vertically provided on the printed circuit board  12  at both sides of the second electronic component  16 . The fixing unit  42  is supported on the printed circuit board  12  by the leg portions  48  at both sides of the second electronic component  16 . Accordingly, even though the fixing unit  42  is fixed to the printed circuit board  12  by the screws  50 , the load acting on the second electronic component  16  from the fixing unit  42  may be reduced. 
         [0043]    The substrate unit  10  may include the first and second electronic components  14  and  16  as examples of a first heating element and a second heating element. Further, the substrate unit  10  may include heating components other than the electronic components, as examples of the first heating element and the second heating element. 
         [0044]    The heat sink  20  may include the fins  56  as an exemplary heat dissipation protruding portions. For example, the heat sink  20  may include protruding portions formed in any shape other than fins, as the heat dissipation protruding portions. For example, the heat sink  18  may include protruding portions formed in any shape other than fins, as the heat dissipation protruding portions. 
         [0045]    The heat dissipation unit  44  may be slidable in the extension direction (in the X direction) of the extension portion  38 . For example, the heat dissipation unit  44  may be slidable in a different direction from the extension direction of the extension portion  38 , such as in the Y direction, or in a direction where the X direction and the Y direction are combined with each other. 
         [0046]    The grooves  62  may be formed in the fixing unit  42 , and the projecting portions  64  may be formed on the heat dissipation unit  44 . For example, the projecting portions  64  may be formed on the fixing unit  42  and the grooves  62  may be formed in the heat dissipation unit  44 . 
         [0047]    The leg portions  48  may be formed integrally with the fixing unit  42 . Alternatively, the leg portions  48  may be formed as separate members from the fixing unit  42 . 
         [0048]    The substrate unit  10  may include the second electronic component  16  as an exemplary heating element. For example, the substrate unit  10  may include anything other than the second electronic component  16 , as the heating element. 
         [0049]      FIG. 5  illustrates an exemplary position change of a heat dissipation unit.  FIG. 5  illustrates the states of the heat dissipation unit of a heat sink before and after the position thereof is changed by perspective views.  FIG. 6  illustrates an exemplary heat sink.  FIG. 6  illustrates an exploded perspective view of the heat sink illustrated in  FIG. 5 .  FIG. 7  illustrates an exemplary cross-sectional view of a heat sink.  FIG. 7  illustrates a cross-sectional view taken along the line  7 - 7  of the heat sink  70  illustrated in  FIG. 5 . The structure of the heat sink  70  illustrated in  FIG. 5  may be different from the structure of the heat sink  20  illustrated in  FIG. 2 . 
         [0050]    For example, as illustrated in  FIG. 6 , a plurality of screw holes  72  are formed in both end portions of the fixing unit  42  in the Y direction. The plurality of screw holes  72  formed in each of the end portions of the fixing unit  42  are aligned in two rows. The plurality of screw holes  72  in each row are aligned in the X direction in which the heat dissipation unit  44  is slid. The plurality of screw holes  72  in one row and the plurality of screw holes  72  in the other row in each end portion are arranged alternately. The number of the screw holes  72  may be optional. 
         [0051]    Communication holes  74  are formed in the end portion of each of the arm portions  58  in the heat dissipation unit  44 , for example, in the end portion opposite to the side of the connection portion  60 . The communication holes  74  are selectively communicated with any of the plurality of screw holes  72  according to the sliding position of the heat dissipation unit  44  with respect to the fixing unit  42 . Metallic screws  76  which are exemplary fixing members are inserted into the communication holes  74  from the side of the heat dissipation unit  44 . When the front end portions of the screws  76  are screwed into the screw holes  72 , the heat dissipation unit  44  may be fixed to the fixing unit  42  while being positioned with respect to the fixing unit  42  in the X direction (see, e.g.,  FIG. 7 ). 
         [0052]    A pair of side wall portions  78  hanging down to the side of the fixing unit  42  are formed at both end portions of the heat dissipation unit  44  in the Y direction. The pair of side wall portions  78  extend in the X direction along both side portions of the fixing unit  42 . 
         [0053]    A heat transfer material such as, a thermal grease may be interposed between the heat dissipation unit  44  and the fixing unit  42  so as to facilitate heat transfer. 
         [0054]    In the heat sink illustrated in  FIGS. 5 to 7 , the communication holes  74  are selectively communicated with any of the plurality of screw holes  72  according to the sliding position of the heat dissipation unit  44  with respect to the fixing unit  42 . By inserting the screws  76  into the communication holes  74  and screwing the end portions of the screws  76  into the screw holes  72 , the heat dissipation unit  44  may be fixed to the fixing unit  42  while being positioned with respect to the fixing unit  42 . Therefore, the sudden movement of the heat dissipation unit  44  with respect to the fixing unit  42  may be suppressed. 
         [0055]    Since the heat dissipation unit  44  and the fixing unit  42  are coupled through the metallic screws  76 , heat may be transferred from the fixing unit  42  to the heat dissipation unit  44  through the screws  76 . Therefore, the heat dissipation of the heat sink  70  may be improved. 
         [0056]    Since the heat dissipation unit  44  is forcedly pressed against the fixing unit  42  through the screws  76 , the adhesion between the heat dissipation unit  44  and the fixing unit  42  may be increased. Therefore, the heat dissipation of the heat sink  70  may be improved. 
         [0057]    The pair of side wall portions  78  are formed on the heat dissipation unit  44  to extend in the sliding direction of the heat dissipation unit  44  along the both side portions of the fixing unit  42 . The sliding direction of the heat dissipation unit  44  is defined with respect to the fixing unit  42  by the pair of side wall portions  78 . Therefore, the operability when the heat dissipation unit  44  is slid, for example, the usability of the heat sink  70  may be improved. 
         [0058]    The plurality of screw holes  72  may be formed in the fixing unit  42  to be aligned in the sliding direction of the heat dissipation unit  44 , and the communication holes  74  may be formed in the heat dissipation unit  44 . Further, the plurality of screw holes  72  may be formed in the heat dissipation unit  44 , and the communication holes  74  may be formed in the fixing unit  42 . By inserting the screws  76  into the communication holes  74  formed in the fixing unit  42  from the fixing unit  42  side and screwing the end portions of the screws  76  into the screw holes  72  formed in the heat dissipation unit  44 , the heat dissipation unit  44  may be fixed to the fixing unit  42 . 
         [0059]    For example, the screw holes  72  and the screws  76  may be used as fixing holes and fixing members. Further, any other components besides the screw holes and the screws such as press-fit holes and press-fit members to be press-fitted into the press-fit holes, may be used as fixing holes and fixing members. 
         [0060]    The pair of side wall portions  78  may be formed on the heat dissipation unit  44 . Further, the pair of side wall portions  78  may be formed on the fixing unit  42  along both side portions of the heat dissipation unit  44 . 
         [0061]      FIG. 8  illustrates an exemplary perspective view of a heat sink. The structure of the heat sink  80  illustrated in  FIG. 8  may be different from the structure of the heat sink  20  illustrated in  FIG. 2 . 
         [0062]    For example, a heat pipe  82  is provided in the fixing unit  42 , and a heat pipe  84  is provided in the heat dissipation unit  44 . Each of the heat pipes  82  and  84  includes at least one portion which extends in the X direction in which the heat dissipation unit  44  is slid. The portion of the heat pipe  82  which extends in the X direction, and the portion of the heat pipe  84  which extends in the X direction may be formed so as to maintain the overlapping state with each other in the X direction regardless of the sliding position of the heat dissipation unit  44 . 
         [0063]    Through this configuration, heat may be transferred by the heat pipes  82  and  84  besides the metal portions of the fixing unit  42  and the heat dissipation unit  44 . Therefore, the heat dissipation of the heat sink  80  may be improved. 
         [0064]    The heat pipes  82  and  84  may be provided in the fixing unit  42  and the heat dissipation unit  44 , respectively. For example, a heat pipe may be provided in any one of the fixing unit  42  and the heat dissipation unit  44 . 
         [0065]      FIG. 9  illustrates an exemplary side cross-sectional view of a substrate unit. The structure of a substrate unit  90  illustrated in  FIG. 9  may be different from the structure of the substrate unit  10  illustrated in  FIG. 1 . 
         [0066]    For example, a connection portion  92  is formed at the end of the heat sink  20  at the side of the first electronic component  14 . The connection portion  92  extends in the height direction of the heat sink  20 , and the top surface of the connection portion  92  is in contact with the bottom surfaces of the fixing unit  22  and the extension portion  38 . One stepped screw  28 , as an exemplary fixture, penetrates the fixing unit  22  and the connection portion  92 . By the common stepped screw  28 , the fixing unit  42  of the heat sink  20  is fixed to the printed circuit board  12 , together with the heat sink  18 . 
         [0067]    Through this configuration, as compared to a case where each of the heat sinks  18  and  20  is independently fixed to the printed circuit board  12 , the number of fixing members (screws) may be reduced. When the number of fixing members is reduced, a space above the printed circuit board  12  is secured, thereby improving the mounting density of the printed circuit board  12 . 
         [0068]    Since the connection portion  92  formed on the fixing unit  42  is in contact with the fixing unit  22  and the extension portion  38  of the heat sink  18 , heat may be transferred from one side to the other side of the heat sink  18  and the heat sink  20 . Therefore, a cooling property of both the first and second electronic components  14  and  16  may be improved. 
         [0069]      FIG. 10  illustrates an exemplary position change of an electronic component.  FIG. 10  illustrates the states of the electronic component of the substrate unit before and after the position thereof is changed by side cross-sectional views. The structure of a substrate unit  100  illustrated in  FIG. 10  may be different from the structure of the substrate unit  10  illustrated in  FIG. 1 . 
         [0070]    In the upper drawing of  FIG. 10 , the state before a position of the second electronic component  16  in the substrate unit  100  is changed is illustrated. In the lower drawing of  FIG. 10 , the state after a position of the second electronic component  16  in the substrate unit  100  is changed is illustrated. For example, according to the specification change of the printed circuit board  12 , as illustrated in the lower drawing of  FIG. 10 , the position of the second electronic component  16  is moved in the X direction. 
         [0071]    According to the position change of the second electronic component  16 , the heat dissipation unit  44  is also slid with respect to the fixing unit  42  in the X direction. A plurality of fins  56  formed on the heat dissipation unit  44  overlap with the second electronic component  16  in the X direction in which the heat dissipation unit  44  is slid. 
         [0072]    Even when the position of the second electronic component  16  is changed, the plurality of fins  56  overlap with the second electronic component  16  because the heat dissipation unit  44  is slid. Thus, a cooling property of the second electronic component  16  may be secured. 
         [0073]    Since the heat dissipation unit  44  is slid with respect to the fixing unit  42 , the placement restriction imposed on the second electronic component  16  may be decreased. Thus, the placement flexibility of the second electronic component  16  may be secured and the mounting density of the printed circuit board  12  may be improved. 
         [0074]    The above described exemplary embodiments may be properly combined with each other. 
         [0075]    All examples and conditional language recited herein are intended for pedagogical purposes to aid the reader in understanding the invention and the concepts contributed by the inventor to furthering the art, and are to be construed as being without limitation to such specifically recited examples and conditions, nor does the organization of such examples in the specification relate to a showing of the superiority and inferiority of the invention. Although the embodiment(s) of the present invention has (have) been described in detail, it should be understood that the various changes, substitutions, and alterations could be made hereto without departing from the spirit and scope of the invention.