Abstract:
The present invention provides a switch having a small longitudinal size of movable contacts and reduced size. The switch includes a base, a pair of fixing terminals standing on an upper surface of the base, an insulating wall section integrated with at least one of the fixing terminals, a push button arranged to be upward and downward movable in the axial direction, and a slider movable upward and downward with the push button. The slider has elastic arm sections in both ends thereof, the elastic arm sections being provided with movable contact portions to be brought into sliding contact with the fixing terminals or the insulating wall section while pressing the fixing terminals or the insulating wall section from one side The switch is configured to enable the movable contact portions to connect to and separate from the fixing terminals based on operation of the push button upward and downward.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Technical Field 
         [0002]    The present invention relates to a switch, particularly to a microswitch for detecting operations of operating parts of an automobile, home appliances, and the like, further to a microswitch including a sliding contact structure. 
         [0003]    2. Related Art 
         [0004]    Conventionally, as a microswitch provided with a sliding contact mechanism, for example, Japanese Utility Model No. 3169859 describes a switch having movable contact portions for nipping fixed contacts in the direction orthogonal to the longitudinal direction in both longitudinal ends of movable contact terminals for switching a conduction state between the fixed contacts. 
         [0005]    However, in the above switch, since the movable contact portions provided in both the longitudinal ends of the movable contacts nip the fixed contacts in the direction orthogonal to the longitudinal direction, longitudinal size of the movable contacts cannot be effectively utilized. Therefore, there is a problem that the switch cannot be reduced in size. 
       SUMMARY 
       [0006]    The present invention has been devised to solve the problem described above, and an object thereof is to provide a switch capable of decreasing longitudinal size of movable contacts and decreasing the size of the switch. 
         [0007]    In accordance with one aspect of the present invention, a switch according to the present invention is a switch including a base, a pair of fixing terminals standing on an upper surface of the base so as to face each other, an insulating wall section integrated with at least one of the fixing terminals, a push button arranged so as to move upward and downward in the axial direction, and a slider moved upward and downward integrally with the push button, wherein the slider has elastic arm sections in both ends thereof, the elastic arm sections being provided with movable contact portions to be brought into sliding contact with the fixing terminals or the insulating wall section while pressing the fixing terminals or the insulating wall section from one side, and by moving the push button upward and downward, the movable contact portions provided in the elastic arm sections are connected to or separated from the fixing terminals. 
         [0008]    Since the elastic arm sections are provided in both the ends of the slider, at the time of ensuring a predetermined contact force, a better contact between the contact portions and fixing terminals can be ensured. Therefore, even when variations are generated in contact force due to variations in part precision and assembling precision, variations in a contact force can be minimized. As a result, a switch with low variations in operation characteristics can be obtained. 
         [0009]    Since there is a space in the longitudinal direction of the slider, the space in the width direction of the switch can be effectively utilized to reduce the size of the switch in such direction. 
         [0010]    As an embodiment of the present invention, an inward surface of the fixing terminal and an inward surface of the insulating wall section may be in a same plane. 
         [0011]    Thereby, the slider can be brought into smooth sliding contact between the insulating wall section and a first fixing terminal. 
         [0012]    As another embodiment of the present invention, the elastic arm sections may have elastic pieces sheared and bent into a substantially V shape. 
         [0013]    Thereby, at the time of assembling the switch, the fixing terminals can be inserted and assembled inside the switch so as to be guided by the elastic pieces of the slider, so that an assembling property is improved. 
         [0014]    As a different embodiment of the present invention, the elastic arm sections may include support pieces extending from both side edges of a coupling body and being bent in the same direction, and the elastic pieces sheared and bent outward from the support pieces into a substantially V shape, and the movable contact portions may be provided in tip ends of the elastic pieces. 
         [0015]    Since the V shape elastic arm sections include the support pieces and the elastic pieces, stock layout of the slider becomes efficient, so that a stock width can be narrowed. Since the elastic arm sections are formed in a V shape, a distance from a center axis of the push button to the movable contact portions is shortened. Thus, even in a case where the push button is inclined, an influence on a contact switch position can be reduced. 
         [0016]    Each of the fixing terminals may include a slide contact section to be brought into sliding contact with the slider, and an externally connecting terminal section connected to an external circuit, the slide contact section and the externally connecting terminal section may be coupled so as to have a predetermined twist angle via a coupling section, and the coupling section may be buried in the base. 
         [0017]    According to the above configuration, strength for supporting the fixing terminals onto the base is enhanced, so that the fixing materials are not easily dropped from the base. Since a creeping distance between the base and the fixing terminals can be extended, sealing airtightness is improved. 
         [0018]    As a different embodiment of the present invention, movable contact portions provided on both sides of the slider may be respectively arranged at positions which are different from a rotation symmetry with respect to a center axis of the push button, and the fixing terminals may be arranged in such a manner that in a case where the slider is rotated by 180° with respect to the center axis in a state that one of the movable contact portions is in contact with the insulating wall section at an initial position serving as a position before pressing the push button, the other movable contact portion is brought into contact with the fixing terminal. 
         [0019]    Thereby, switches of two specifications including an always-closed contact structure and an always-open contact structure can be made by the same constituent parts. Without changing a shape of the pair of elastic arm sections, the switches of the two specifications can be obtained. 
         [0020]    As a different embodiment of the present invention, the slider may be insert-molded to the push button. 
         [0021]    Thereby, the slider is integrated with the push button, so that the number of parts and the number of assembling steps are decreased, and the variations in the operation characteristics of the slider are eliminated, so that contact reliability can be enhanced. 
         [0022]    As another embodiment of the present invention, the slider may be integrated with the push button by thermal caulking or snap-fitting. Thereby, there is an effect that a selection range of an assembling method is widened, so that the switch is easily manufactured. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0023]      FIG. 1  is a perspective view showing a switch according to the present invention; 
           [0024]      FIG. 2A  is an exploded perspective view in which a switch according to a first embodiment of the present invention is seen from the upper side;  FIG. 2B  is an exploded perspective view in which  FIG. 2A  is seen from the lower side; 
           [0025]      FIG. 3A  is a perspective view in which a slider of  FIGS. 2A and 2B  is seen from the upper side;  FIG. 3B  is a perspective view in which  FIG. 3A  is seen from the lower side; 
           [0026]      FIG. 4A  is a perspective view showing a relationship between the slider and a first fixing terminal in a state that the switch of  FIGS. 2A and 2B  is at an initial position;  FIG. 4B  is a perspective view corresponding to  FIG. 4A  in which the switch is at an operation position; 
           [0027]      FIG. 5A  is a perspective view showing a relationship between a slider and a first fixing terminal in a state that a switch according to a modified example of the first embodiment is at an initial position;  FIG. 5B  is a perspective view corresponding to  FIG. 5A  in which the switch is at an operation position; 
           [0028]      FIG. 6A  is an exploded perspective view in which a switch according to a second embodiment of the present invention is seen from the upper side;  FIG. 6B  is an exploded perspective view in which  FIG. 6A  is seen from the lower side; 
           [0029]      FIG. 7A  is an enlarged perspective view of parts of a slider of  FIGS. 6A and 6B ;  FIG. 7B  is a perspective view showing a relationship between the slider and a first fixing terminal in a state that the slider of  FIG. 7A  is assembled to the switch; 
           [0030]      FIG. 8A  is an exploded perspective view in which a switch according to a third embodiment of the present invention is seen from the upper side;  FIG. 8B  is an exploded perspective view in which  FIG. 8A  is seen from the lower side; 
           [0031]      FIG. 9  is a side view of a state that the slider is insert-molded to a push button; 
           [0032]      FIG. 10A  is a perspective view showing a relationship between the slider and the first fixing terminal in a state that the switch adopting an always-open contact structure in  FIGS. 8A and 8B  is at an initial position;  FIG. 10B  is a perspective view corresponding to  FIG. 10A  in which the switch is at an operation position; 
           [0033]      FIG. 11A  is a perspective view showing a relationship between the slider and the first fixing terminal in a state that the switch adopting an always-closed contact structure in  FIGS. 8A and 8B  is at an initial position;  FIG. 11B  is a perspective view corresponding to  FIG. 11A  in which the switch is at an operation position; 
           [0034]      FIG. 12A  is an exploded perspective view in which a switch according to a fourth embodiment of the present invention is seen from the upper side;  FIG. 12B  is an exploded perspective view in which  FIG. 12A  is seen from the lower side; 
           [0035]      FIG. 13A  is a perspective view showing a relationship between a slider and a first fixing terminal in a state that the switch adopting an always-open contact structure in  FIGS. 12A and 12B  is at an initial position;  FIG. 13B  is a perspective view corresponding to  FIG. 13A  in which the switch is at an operation position; 
           [0036]      FIG. 14A  is a perspective view showing a relationship between the slider and the first fixing terminal in a state that the switch adopting an always-closed contact structure in  FIGS. 12A and 12B  is at an initial position; and  FIG. 14B  is a perspective view corresponding to  FIG. 14A  in which the switch is at an operation position. 
       
    
    
     DETAILED DESCRIPTION 
       [0037]    Embodiments of a switch according to the present invention will be described in accordance with  FIGS. 1 to 14A  and  14 B. 
       First Embodiment 
       [0038]    A switch  11  according to a first embodiment includes a push button  12 , a casing  17 , a base  21 , a first fixing terminal  31 , a second fixing terminal  36 , and a slider  41  as shown in  FIGS. 1 ,  2 A, and  2 B. 
         [0039]    The push button  12  has a seat  13  in which a recessed portion is formed, and a cylindrical pressed section  14  extending upward from the seat  13  in the axial direction. The push button  12  is arranged inside the casing  17  movably in the axial direction orthogonal to the base  21 , and an upper end of the pressed section  14  protrudes upward from the casing  17  through a cylindrical cap  15 . Therefore, the pressed section  14  is pressed from an exterior, so that the push button  12  is moved in the axial direction. 
         [0040]    The casing  17  is formed in a box shape in which a bottom portion is opened, and has an annular groove  18  formed on an upper surface thereof, the annular groove through which the pressed section  14  of the push button  12  is inserted, and a pair of annular positioning projections  19  horizontally protruding from a side surface thereof. 
         [0041]    The base  21  is a plate shape resin body for closing an opening in the bottom portion of the casing  17 . In the base  21 , an insulating wall section  22  extending upward is integrally formed on an upper surface thereof, and a cylindrical rib  23  protruding upward is provided in a center of the base  21 . The insulating wall section  22  includes a burying groove  25  formed in a rectangular shape in a front view and provided on an inner surface thereof, the burying groove into which the first fixing terminal  31  is buried, and an insulation portion  26  provided on the upper side of the burying groove  25 . Further, terminal holes  27  through which the first fixing terminal  31  and the second fixing terminal  36  are inserted are formed in the base  21 . 
         [0042]    The first fixing terminal  31  is made of metal, and has a rectangular plate shape first slide contact section  32  formed in an upper half part thereof extending in the axial direction, and a rectangular plate shape first externally connecting terminal section  33  formed in a lower half part thereof extending in the axial direction. The first slide contact section  32  and the first externally connecting terminal section  33  are coupled so as to have a right twist angle. A first inward projection  35   a,  and a first outward projection  35   b  protruding on the opposite side of the first inward projection  35   a  are formed in a coupling section  35 . In a state that the first fixing terminal  31  is fixed to the base  21  via the terminal hole  27 , the first slide contact section  32  is buried in the burying groove  25  so as to be flush with the insulation portion  26  and brought into sliding contact with the slider  41  moved in the axial direction. Meanwhile, the first externally connecting terminal section  33  is exposed downward from the terminal hole  27  and connected to an external terminal (external circuit (not shown)). 
         [0043]    The second fixing terminal  36  is made of metal, and has a rectangular plate shape second slide contact section  37  formed in an upper half part thereof extending in the axial direction, and a rectangular plate shape second externally connecting terminal section  38  formed in a lower half part thereof extending in the axial direction. The second slide contact section  37  and the second externally connecting terminal section  38  are coupled so as to have a right twist angle. A second inward projection  39   a,  and a second outward projection  39   b  protruding on the opposite side of the second inward projection  39   a  are formed in a coupling section  39 . The second slide contact section  37  is formed to be longer than the first slide contact section  32  of the first fixing terminal  31 . In a state that the second fixing terminal  36  is fixed to the base  21  via the terminal hole  27 , the second slide contact section  37  is always in contact with the slider  41 . Meanwhile, the second externally connecting terminal section  38  is exposed downward from the terminal hole  27  and connected to an external terminal (not shown). 
         [0044]    The slider  41  according to the present invention has a plate shape coupling body  42 , and elastic arm sections  43  formed by bending both ends of the coupling body  42  as shown in  FIGS. 3A and 3B . The elastic arm sections  43  include support pieces  45  of rectangular frame bodies extending vertically downward from both the ends of the coupling body  42 , lower sides  46  coupled to the support pieces  45 , and elastic pieces  47  sheared and bent outward from the lower sides  46  into a V shape. Movable contact portions  48 ,  48  to be brought into sliding contact with the insulation portion  26  of the insulating wall section  22  or the first fixing terminal  31  while pressing the insulation portion or the first fixing terminal from one side, and movable contact portions  49 ,  49  to be brought into sliding contact with the second fixing terminal  36  while pressing the second fixing terminal from one side are formed in tip ends of the elastic pieces  47 . Since the elastic arm sections  43  extend in the longitudinal direction of the slider  41 , at the time of ensuring a predetermined contact force, a better contact between the two terminals can be ensured. Therefore, even when variations are generated in contact follow due to variations in part precision and assembling precision, variations in a contact force can be minimized. As a result, a switch with low variations in operation characteristics can be obtained. Since a space in the longitudinal direction of the slider  41 , that is, a space in the width direction of the switch  11  can be effectively utilized, the switch  11  can be downsized in such direction. Further, since the V shape elastic arm sections  43  include the support pieces  45  and the elastic pieces  47 , stock layout of the slider  41  becomes efficient, so that a stock width can be narrowed. 
         [0045]    Next, an assembling method of the switch  11  including the above constituent members will be described. 
         [0046]    Firstly, the cap  15  is fitted into the annular groove  18  of the casing  17 . The push button  12  is inserted inside the casing  17  movably in the axial direction, so that the upper end of the pressed section  14  protrudes from the cap  15 . It should be noted that the slider  41  is insert-molded to the recessed portion of the seat  13  of the push button  12  in advance. Thereby, the slider  41  is integrated with the push button  12 , so that the number of parts and the number of assembling steps are decreased, and the variations in the operation characteristics of the slider  41  are eliminated, so that contact reliability can be enhanced. However, the slider  41  may be fixed to the push button  12  by thermal caulking or snap-fitting. At this time, a selection range of the assembling method is widened, so that the switch is easily manufactured. After that, an upper end of a coil spring  50  is abutted with the recessed portion of the seat  13 . 
         [0047]    The first fixing terminal  31  is insert-molded to the base  21  in advance so that the first inward projection  35   a  and the first outward projection  35   b  of the first fixing terminal  31  are buried in the base  21 . 
         [0048]    At this time, the first slide contact section  32  of the first fixing terminal  31  is buried in the burying groove  25  of the insulating wall section  22  so as to be flush with the insulation portion  26  (refer to  FIG. 4A ). Therefore, the slider  41  can be brought into smooth sliding contact between the insulation portion  26  and the first fixing terminal  31 . Similarly, the second fixing terminal  36  is insert-molded to the base  21  in advance so that the second inward projection  39   a  and the second outward projection  39   b  of the second fixing terminal  36  are buried in the base  21 . Thereby, strength for supporting the first fixing terminal  31  and the second fixing terminal  36  onto the base  21  is enhanced, so that the first fixing terminal  31  and the second fixing terminal  36  are not easily dropped from the base  21 . Since a creeping distance between the base  21  and the first fixing terminal  31  and the second fixing terminal  36  can be extended, sealing airtightness can be improved. 
         [0049]    Further, the base  21  is installed in the opening of the casing  17  so that the cylindrical rib  23  of the base  21  is engaged with the other end of the coil spring  50  so as to compress the coil spring  50 , and the first fixing terminal  31  and the second fixing terminal  36  are accommodated inside the casing  17 . At this time, since the elastic arm sections  43  are formed in a V shape, the first fixing terminal  31  and the second fixing terminal  36  can be inserted and assembled inside the switch  11  so as to be guided by the elastic arm sections  43 , so that an assembling property is improved. Thereby, the switch  11  is completed. 
         [0050]    Next, operations of the assembled switch  11  will be described. When the switch  11  is assembled, as shown in  FIG. 4A , the slider  41  is biased by the coil spring  50  and placed at an initial position on the upper side (position before pressing the pressed section  14  of the push button  12 ). At this time, the movable contact portions  48 ,  48  on the one side are abutted with the insulation portion  26  of the insulating wall section  22 , and the movable contact portions  49 ,  49  on the other side are abutted with the second slide contact section  37  of the second fixing terminal  36 , so that the switch is insulated. When the pressed section  14  of the push button  12  is pressed from the exterior in this state, the push button  12  is moved with the slider  41  downward in the axial direction against a bias force of the coil spring  50 . Then, in the slider  41 , the elastic arm sections  43  are moved downward and brought into sliding contact with the first slide contact section  32  of the first fixing terminal  31  after the insulation portion  26 . When the slider reaches an operation position shown in  FIG. 4B , the movable contact portions  48 ,  48  on the one side are abutted with the first slide contact section  32  and the movable contact portions  49 ,  49  on the other side are abutted with the second slide contact section  37 , so that the switch conducts. Thereby, the external terminals respectively connected to the first and second externally connecting terminal sections  33 ,  38  are brought into a conduction state. When a pressing force toward the pressed section  14  of the push button  12  is cancelled, the push button  12  is moved with the slider  41  upward in the axial direction by the bias force of the coil spring  50 . Then, in the slider  41 , the elastic arm sections  43  are moved upward, brought into sliding contact with the insulation portion  26  after the first slide contact section  32 , and returned to the initial position. Therefore, the movable contact portions  48 ,  48  on the one side are abutted with the insulation portion  26  of the insulating wall section  22 , and the movable contact portions  49 ,  49  on the other side are abutted with the second slide contact section  37 , so that the switch is brought into non-conducting state. It should be noted that when the elastic arm sections  43  are formed into a V shape, a distance from a center axis of the push button  12  to the movable contact portions  48 ,  49  is shortened. Thus, even in a case where the push button  12  is inclined, an influence on a contact switch position can be reduced. 
         [0051]    The present invention is not limited to the first embodiment but can be variously modified. 
         [0052]    In the first embodiment, the first slide contact section  32  of the first fixing terminal  31  is provided on the lower side of the insulation portion  26 . However, the present invention is not limited to this. For example, as in a modified example of the first embodiment shown in  FIGS. 5A and 5B , a configuration that a first slide contact section  34  of a first fixing terminal  31  is provided on an upper inner surface of an insulating wall section  22  and an insulation portion  26  is formed on the lower side may be adopted. Thereby, when a slider  41  is at an initial position (refer to  FIG. 5A ), movable contact portions  48 ,  48  on the one side are abutted with the first slide contact section  34  and movable contact portions  49 ,  49  on the other side are abutted with a second slide contact section  37 , so that the switch conducts. When a push button (not shown) is pressed and the slider  41  is at an operation position ( FIG. 5B ), the movable contact portions  48 ,  48  on the one side are abutted with the insulation portion  26  of the insulating wall section  22  and the movable contact portions  49 ,  49  on the other side are abutted with the second slide contact section  37 , so that the switch is insulated and hence a conduction state of the external terminals may be switched. It should be noted that in  FIGS. 5A and 5B , for convenience of description, a push button  12  and a coil spring  50  are not shown. The same is applied to the following figures. 
       Second Embodiment 
       [0053]    In the first embodiment, the elastic pieces  47  of the slider  41  are sheared and bent outward from the lower sides  46  of the support pieces  45 . However, the present invention is not limited to this. For example, as in a switch  51  according to a second embodiment shown in  FIGS. 6A and 6B , a slider  52  may have a coupling body  53  including a pair of facing frame bodies, and elastic arm sections  54  formed by bending both ends of the coupling body  53 . As shown in  FIG. 7A , the elastic arm sections  54  include support pieces  56  of rectangular frame bodies extending vertically upward from both edges of the coupling body  53 , upper sides  57  coupled to the support pieces  56 , and elastic pieces  58  sheared and bent outward from the upper sides into a V shape which is made by turning the shape of the first embodiment upside down. Movable contact portions  59 ,  59  to be brought into sliding contact with an insulation portion  26  of an insulating wall section  22  or a first fixing terminal  31  while pressing the insulation portion or the first fixing terminal from one side, and movable contact portions  60 ,  60  to be brought into sliding contact with a second fixing terminal  36  while pressing the second fixing terminal from one side are formed in tip ends of the elastic pieces  58 . 
         [0054]    In a state that the slider  52  is assembled to the switch  51 , the coupling body  53  is insert-molded to a lower portion of a seat  13  of a push button  12 , and a coil spring  50  is inserted through a clearance of the coupling body  53  and abutted with the seat  13 . As shown in  FIG. 7B , a first slide contact section  32  of the first fixing terminal  31  is formed to be shorter than the first embodiment, and the insulation portion  26  of the insulating wall section  22  is formed to be long in the axial direction. Apart from the point, the second embodiment is the same as the first embodiment. Thus, the same parts will be given the same reference numerals and description thereof will not be given. 
         [0055]    When the switch  51  is assembled, at an initial position (refer to  FIG. 7B ), the movable contact portions  59 ,  59  on the one side are abutted with the insulation portion  26  of the insulating wall section  22 , and the movable contact portions  60 ,  60  on the other side are abutted with a second slide contact section  37 , so that the switch is insulated. When the push button  12  is pressed and the slider  52  is moved downward and reaches an operation position, the movable contact portions  59 ,  59  on the one side are abutted with the first slide contact section  32  and the movable contact portions  60 ,  60  on the other side are abutted with the second slide contact section  37 , so that the switch conducts. Since returning is the same as the first embodiment, description thereof will not be given. 
       Third Embodiment 
       [0056]    In a first fixing terminal  63  of a switch  62  according to a third embodiment shown in  FIGS. 8A and 8B , a first contact section  64  has a rectangular plate shape sliding piece  65 , and a sliding block  66  extending obliquely upward from an upper corner portion of the sliding piece  65 . A burying groove  67  of an insulating wall section  22  is formed into a shape corresponding to the first contact section  64 . Thereby, two insulation portions  68 ,  69  are formed so as to face each other across the first contact section  64  buried in the burying groove  67  in the insulating wall section  22  (refer to  FIG. 10A ). 
         [0057]    Further, as shown in  FIGS. 8A and 8B , elastic arm sections  43  of a slider  70  respectively have one movable contact portion  48  and one movable contact portion  49 , and the slider  70  is formed to be narrow. As shown in  FIG. 9 , the slider  70  is insert-molded to a seat  13  of a push button  12  while being slightly displaced from a center line L. That is, the movable contact portions  48 ,  49  are arranged at positions which are different from a rotation symmetry with respect to a center axis of the push button  12 . Therefore, the slider  70  can be arranged in an always-open contact structure shown in  FIGS. 10A and 10B , and an always-closed contact structure shown in  FIGS. 11A and 11B , the always-closed contact structure being formed by rotating the slider  70  by 180 degrees with respect to the center axis of the push button  12  from the always-open contact structure. Apart from the point, the third embodiment is the same as the first embodiment. Thus, the same parts will be given the same reference numerals and description thereof will not be given. 
         [0058]    When the switch  62  is assembled, in the always-open contact structure, at an initial position (refer to  FIG. 10A ), the movable contact portion  48  on the one side is abutted with the insulation portion  68  of the insulating wall section  22 , and the movable contact portion  49  on the other side is abutted with a second slide contact section  37 , so that the switch is insulated. When the push button  12  is pressed and the slider  70  is moved downward and reaches an operation position (refer to  FIG. 10B ), the movable contact portion  48  on the one side is abutted with the sliding piece  65  of the first fixing terminal  63  and the movable contact portion  49  on the other side is abutted with the second slide contact section  37 , so that the switch conducts. Since returning is the same as the first embodiment, description thereof will not be given. 
         [0059]    Meanwhile, when the slider  70  is rotated by 180 degrees with respect to the center axis of the push button  12 , the structure becomes the always-closed contact structure. That is, at an initial position (refer to  FIG. 11A ), the movable contact portion  48  on the one side is abutted with the sliding block  66  of the first fixing terminal  63  and the movable contact portion  49  on the other side is abutted with the second slide contact section  37 , so that the switch conducts. When the push button  12  is pressed and the slider  70  is moved downward and reaches an operation position (refer to  FIG. 11B ), the movable contact portion  48  on the one side is abutted with the insulation portion  69  of the insulating wall section  22  and the movable contact portion  49  on the other side is abutted with the second slide contact section  37 , so that the switch is insulated. Since returning is the same as the first embodiment, description thereof will not be given. As described above, switches of two specifications including the always-closed contact structure and the always-open contact structure can be made by the same constituent parts. 
       Fourth Embodiment 
       [0060]    In a first fixing terminal  73  of a switch  72  according to a fourth embodiment shown in  FIGS. 12A and 12B , a first contact section  74  has a rectangular plate shape sliding piece  75 , and a pair of sliding blocks  76  extending obliquely upward from both upper corner portions of the sliding piece  75 . A burying groove  77  of an insulating wall section  22  is formed into a shape corresponding to the first contact section  74 . Thereby, a rectangular insulation portion  78  formed in a center of an upper portion, and a pair of insulation portions  79  formed in parallel along both lower edges of the rectangular insulation portion  78  are formed in the insulating wall section  22  (refer to  FIG. 13B ). 
         [0061]    Further, a slider  81  is provided with an elastic arm section  43  formed by bending one end of a coupling body  42 , and a switching elastic arm section  82  formed by bending the other end. As shown in  FIG. 14A , the switching elastic arm section  82  includes linear support pieces  83  extending vertically downward from a center of one side edge of the coupling body  42 , a lower side  84  extending outward from both lower ends of the support pieces  83 , and elastic pieces  85  sheared and bent outward from both ends of the lower side  84  into a V shape. Movable contact portions  86  to be brought into sliding contact with the sliding blocks  76  or the insulation portions  79  while pressing the sliding blocks or the insulation portions from one side are formed in tip ends of the elastic pieces  85 . That is, the movable contact portions  48 ,  86  are arranged at positions which are different from a rotation symmetry with respect to a center axis of a push button  12 . Therefore, the slider  81  can be arranged in an always-open contact structure shown in  FIGS. 13A and 13B , and an always-closed contact structure shown in  FIGS. 14A and 14B , the always-closed contact structure being formed by rotating the slider  81  by 180 degrees with respect to the center axis of the push button  12  from the always-open contact structure. Apart from the point, the fourth embodiment is the same as the first embodiment. Thus, the same parts will be given the same reference numerals and description thereof will not be given. 
         [0062]    When the switch  72  is assembled, in the always-open contact structure, at an initial position (refer to  FIG. 13A ), the movable contact portions  48 ,  48  on the one side are abutted with the insulation portion  78  of the insulating wall section  22 , and the movable contact portions  86  on the other side are abutted with a second slide contact section  37 , so that the switch is insulated. When the push button  12  is pressed and the slider  81  is moved downward and reaches an operation position (refer to  FIG. 13B ), the movable contact portions  48 ,  48  on the one side are abutted with the sliding piece  75  of the first fixing terminal  73  and the movable contact portions  86  on the other side are abutted with the second slide contact section  37 , so that the switch conducts. Since returning is the same as the first embodiment, description thereof will not be given. 
         [0063]    Meanwhile, when the slider  81  is rotated by 180 degrees with respect to the center axis of the push button  12 , the structure becomes the always-closed contact structure. In the always-closed contact structure, at an initial position (refer to  FIG. 14A ), the movable contact portions  86 ,  86  on the one side are abutted with the sliding blocks  76 ,  76  of the first fixing terminal  73  and the movable contact portions  48 ,  48  on the other side are abutted with the second slide contact section  37 , so that the switch conducts. When the push button  12  is pressed and the slider  81  is moved downward and reaches an operation position (refer to  FIG. 14B ), the movable contact portions  86 ,  86  on the one side are abutted with the insulation portions  79  of the insulating wall section  22  and the movable contact portions  48 ,  48  on the other side are abutted with the second slide contact section  37 , so that the switch is insulated. Since returning is the same as the first embodiment, description thereof will not be given. 
         [0064]    There has thus been shown and described a switch which fulfills all the objects and advantages sought therefore. Many changes, modifications, variations and other uses and applications of the subject invention will, however, become apparent to those skilled in the art after considering this specification and the accompanying drawings which disclose the preferred embodiments thereof. All such changes, modifications, variations and other uses and applications which do not depart from the spirit and scope of the invention are deemed to be covered by the invention, which is to be limited only by the claims which follow. 
         [0065]    Although the invention has been described in detail for the purpose of illustration based on what is currently considered to be the most practical and preferred embodiments, it is to be understood that such detail is solely for that purpose and that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover modifications and equivalent arrangements that are within the spirit and scope of the appended claims. For example, it is to be understood that the present invention contemplates that, to the extent possible, one or more features of any embodiment can be combined with one or more features of any other embodiment.