Patent Publication Number: US-8525622-B2

Title: Electromagnetic relay

Description:
BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     The present invention relates to an electromagnetic relay. 
     2. Description of the Related Art 
     There is a known electromagnetic relay which includes an electromagnet in which an iron core is attached to a bobbin having a coil; an armature moved according to voltage applied to the coil; and a contact portion openable and closable according to a movement of the armature, wherein the contact portion has a pair of fixed contacts and a pair of movable contacts opposed to the pair of fixed contacts. In the electromagnetic relay described in Japanese Unexamined Patent Publication (kokai) No. 2010-73323 (JP2010-73323A), movable contacts are provided at both end portions of an conductive plate, and when each movable contact is contacted to each fixed contact at the time of operation of the electromagnetic relay, the fixed contacts are electrically connected to each other in series through the movable contacts. 
     However, in this type of electromagnetic relay, fixed contacts are arranged at one end portion of a pair of plate-shaped fixed contact members and movable contacts are arranged at one end portion of a pair of movable contact members and further terminals are arranged at the other end portion. Therefore, it is difficult to change the terminal arrangement. 
     SUMMARY OF THE INVENTION 
     The present invention provides an electromagnetic relay comprising an electromagnet device having an electromagnet in which an iron core is attached to a bobbin with a coil wound thereon, and an armature attracted to or separated from the iron core according to voltage applied to the coil; a contact portion openable and closable according to a movement of the armature, the contact portion including a plurality of fixed contact members in which fixed contacts are respectively arranged and a plurality of movable contact members in which movable contacts opposed to the fixed contacts are respectively arranged, wherein the plurality of movable contact members operate according to a movement of the armature; a printed board to which the plurality of fixed contact members and the plurality of movable contact members are respectively electrically connected; and a plurality of contact terminal members electrically connected to the printed board and adapted to be connected to electrical parts provided outside. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The object, features and advantages of the present invention will become more apparent from the following description of embodiments taken in conjunction with the accompanying drawings, in which: 
         FIG. 1  is a perspective view showing an appearance configuration of the electromagnetic relay according to the embodiment of the present invention; 
         FIG. 2  is an exploded perspective view of the electromagnetic relay shown in  FIG. 1 ; 
         FIG. 3   a  is a perspective view showing a configuration of the electromagnetic relay body shown in  FIG. 2 ; 
         FIG. 3   b  is a perspective view showing a configuration of the electromagnetic relay body shown in  FIG. 2 ; 
         FIG. 4  is a perspective view showing a state of accommodation in which a pair of electromagnetic relay bodies shown in  FIG. 2  are accommodated in a housing; 
         FIG. 5  is a perspective view showing constitution of a printed board and tab terminals shown in  FIG. 2 ; 
         FIG. 6  is a plan view showing an internal structure of the electromagnetic relay shown in  FIG. 1 , that is,  FIG. 6  is a view of the printed board taken from the upside; 
         FIG. 7  is a view showing a first variation of the electromagnetic relay shown in  FIG. 6 ; 
         FIG. 8  is a view showing a second variation of the electromagnetic relay shown in  FIG. 6 ; 
         FIG. 9  is a view showing a third variation of the electromagnetic relay shown in  FIG. 6 ; 
         FIG. 10  is a view showing an example in which a magnet is attached to a housing of the electromagnetic relay according to the embodiment of the present invention. 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIGS. 1 to 10 , an embodiment of the present invention will be explained below.  FIG. 1  is a perspective view showing an appearance configuration of the electromagnetic relay according to the embodiment of the present invention.  FIG. 2  is an exploded perspective view of the electromagnetic relay shown in  FIG. 1 . In this connection, the directions of front, rear, right, left, up and down are defined as follows for convenience and the constitution of each portion will be explained by using the directions. 
     As shown in  FIG. 2 , the electromagnetic relay of the present embodiment includes an electromagnetic relay assembling body  1 ; a housing  2  for accommodating the electromagnetic relay assembling body  1 ; and a cover  3  for covering an upper portion of the housing  2 . The electromagnetic relay assembling body  1  includes a pair of right and left electromagnetic relay bodies  4 ; a printed board  5  arranged above the electromagnetic relay bodies  4 ; and tab terminals  6  protruded upward from an upper face of the printed board  5 . 
     The housing  2  is a resinous component made of electrical insulating material, and is formed by integral molding. An upper face of this housing  2  is open, and the entire housing  2  is formed into a substantial box-shape. Flange portions  201  are provided at front and rear end portions in a lower end portion of the housing  2  so that the housing  2  is attachable to various parts through the flange portions  201  by using screws or the like. A step portion  202  is provided in a horizontal direction throughout the entire upper inside of the housing  2 . Further, on front and rear insides of the housing  2  above the step portion  202 , a step portion  203  is provided in a horizontal direction. Substantially rectangular through-holes  204  and  205  are provided at upper portions on right and left surfaces of the housing  2 , and are separate from each other in the up-down direction. 
     The cover  3  is a resinous component made of an electrical insulating material, and is formed by integral molding. The cover  3  is formed into a substantially rectangular plate shape. Slit holes  301  are provided at positions respectively corresponding to the tab terminals  6  on the cover  3 . Protruding portions  302  are provided at right and left end portions of the cover  3 , and protrude downward and outside in the right-left direction. When the tab terminals  6  are made to penetrate the slit holes  301  and the protruding portions  302  are inserted into the upper through-holes  205  of the housing  2 , the cover  3  is fixed onto an upper face of the housing  2 , under the condition that the tab terminals  6  are protruded from the cover  3  as shown in  FIG. 1 . In this connection, rear side tab terminals  6   a  are tab terminals (coil terminal members) for applying voltage to the coil of the electromagnetic relay, and front side tab terminals  6   b  are contact tab terminals (contact terminal members) for electrifying the contacts of the electromagnetic relay. 
     The pair of right and left electromagnetic relay bodies  4  shown in  FIG. 2  are formed into the same profile.  FIGS. 3   a  and  3   b  are perspective views in which one of the electromagnetic relay bodies  4  are viewed from above and below. As shown in  FIGS. 3   a  and  3   b , the electromagnetic relay body  4  includes a base portion  10 ; an electromagnet device  20  attached to the base portion  10 ; and a contact portion  30  openable and closable according to an action of the electromagnet device  20 . 
     The base portion  10  is a resinous component made of electrical insulating material, and is formed by means of integral forming. The entire base portion  10  is formed into a substantially rectangular block shape. The base portion  10  has a support portion for supporting the electromagnet device  20  and the contact portion  30 . In this connection, the detailed explanations of the support portion will be omitted here. A step-shaped end face  11  is formed in a periphery of the base portion  10  so as to contact the step portion  202  (shown in  FIG. 2 ) formed on the inside of the housing  2 . Further, protruding portions  12  are provided on the right and left sides of the base portion  10  so as to be inserted into the lower side through-holes  204  (shown in  FIG. 2 ). 
     The electromagnet device  20  includes an electromagnet  23  in which an iron core  22  is inserted into a cylindrical bobbin (not shown) to which a coil  21  is wound thereon, and an armature  24  attracted to or separated from the iron core  22  according to voltage applied to the coil  21 . A pair of right and left coil terminals  25  are provided at the rear end portion of the base portion  10  so as to penetrate the base portion  10  in the up-down direction. Both end portions of a winding wire of the coil  21  are connected to lower end portions of the coil terminals  25 , so that voltage is applied to the coil  21  through the coil terminals  25 . 
     The bobbin of the electromagnet  23  is arranged at a rear portion of the base portion  10 , and the iron core  22  is accommodated inside the bobbin in the up-down direction. The armature  24  is a substantially L-shaped plate member made of soft magnetic material such as iron. 
     The armature  24  includes a horizontal portion  24   a  arranged facing a lower end face of the iron core  22 , and a vertical portion  24   b  extending in a substantially vertical direction from a front end portion of the horizontal portion  24   a  to the base portion  10 . A substantially rectangular yoke  26  is arranged between the coil  21  of the electromagnet  23  and the vertical portion  24   b  of the armature  24 . The yoke  26  extends in the up-down direction. A width of the yoke  26  in the right left direction is substantially the same as that of the armature  24 . The yoke  26  is supported by the base portion  10 . The armature  24  capable of oscillating is supported on a lower end face of the yoke  26 . 
     A card  27  is arranged in front of the vertical portion  24   b  of the armature  24 . The card  27  is an insulating body made of electrical insulating material. The card  27  integrally includes a horizontal portion  27   a  extending in the front-rear direction; a vertical portion  27   b  extending in the up-down direction from a rear end of the horizontal portion  27   a ; and a side wall portion  27   c  extending forward from right and left end portions of the vertical portion  27   b . A rear end portion of the horizontal portion  27   a  is connected to the vertical portion  24   b  of the armature  24  so that the card  27  is moved in the front-rear direction according to oscillation of the armature  24 . 
     The contact portion  30  includes a movable contact plate member  31  arranged in front of the vertical portion  27   b  of the card  27 , and a fixed contact plate member  32  arranged in front of the movable contact plate member  31 . The fixed contact plate member  32  is composed of, for example, a conductive plate member formed by die-cutting a copper plate into a predetermined shape. The movable contact plate member  31  is composed of, for example, a conductive plate member formed by die-cutting a phosphor bronze sheet for spring into a predetermined shape. The movable contact plate member  31  and the fixed contact plate member  32  are plate members formed widely in the right and left direction. These members  31  and  32  are extended in the up-down direction, and a width of the plate member  31  in the right-left direction is substantially the same as that of the plate member  32 . The vertical portion  27   b  of the card  27  and the movable contact plate member  31  are opposed to each other, and the movable contact plate member  31  and the fixed contact plate member  32  are also opposed to each other. The movable contact plate member  31  is connected to a pair of right and left side wall portions  27   c  of the card  27  at a somewhat lower portion of its center. 
     The movable contact plate member  31  and the fixed contact plate member  32  are respectively supported by the support portions  13  and  14  formed in the base portion  10 . It is not necessary that each plate member  31  and  32  has a constant width all over the length. For example, the width of each plate member  31 ,  32  is extended in the support portions  13 ,  14 . A conductive movable contact  33  is fixed on a front face at a lower end portion of the movable contact plate member  31 , and a conductive fixed contact  34  is fixed on a rear face at a lower end portion of the fixed contact plate member  32 , opposed to the conductive movable contact  33 . 
     A terminal  35  for movable contact  33  is provided at an upper end of the movable contact plate member  31 . A terminal  36  for fixed contact  34  is provided at an upper end of the fixed contact plate member  32 . These terminals  35  and  36  are formed in such a manner that an upper end portion of each plate member  31  and  32  is formed into a long and slender shape. These terminals  35  and  36  respectively penetrate the base portion  10  and protrude upward. When a profile of the upper end portion of each plate member  31  and  32  is appropriately formed, each terminal  35  and  36  can be protruded from an arbitrary position in the base portion  10 . As shown in  FIG. 3   b , in the present embodiment, the terminal  36  protrudes from the left front end portion of the base portion  10 , and the terminal  35  protrudes from a right oblique rear portion of the terminal  36 . 
     In this electromagnetic relay body  4 , when operation voltage is applied to the coil  21  of the electromagnet  23 , the electromagnet device  23  is operated, and the armature  24  is oscillated round the lower end of the yoke  26  by a magnetic attraction force of the electromagnet device  23 . By this oscillation of the armature  24 , the card  27  is pushed forward, and the movable contact plate member  31  is elastically bent and deformed forward about the support portion  13  of the base portion  10 , and therefore, the movable contact  33  comes into contact with the fixed contact  34 . On the other hand, when the operation voltage applied to the coil  21  is released, the electromagnet device  23  becomes a non-active state, and the movable contact plate member  31  is released from a pushing force acting to the front direction. As a result, the movable contact plate member  31  is returned to an initial position shown in  FIGS. 3   a  and  3   b  by a function as a leaf spring, and therefore, the movable contact  33  is separated from the fixed contact  34 . 
       FIG. 4  is a perspective view showing a state in which the pair of electromagnetic relay bodies shown in  FIG. 2  are accommodated in the housing. Inside the housing  2 , a bulkhead  206  is provided along the front-rear direction at the center of the right-left direction. An inside space of the housing  2  is divided into two accommodation spaces  207  by the bulkhead  206 . A pair of electromagnetic relay bodies  4  are respectively separately accommodated into the accommodation spaces  207  from above, as shown in the drawing. At this time, the end face  11  of the base portion  10  comes into contact with the step portion  202  of the housing  2  and the protruding portion  12  is inserted into the through-hole  204 , so that the electromagnetic relay body  4  can be supported in the housing  2 . When the electromagnetic relay body  4  is accommodated in the housing  2 , four coil terminals  25 , two terminals  35  for movable contacts  33  and two terminals  36  for fixed contacts  34  are respectively protruded upward. 
     In the present embodiment, these terminals  25 ,  35  and  36  are connected to the printed board  5  arranged above the base portion  10 .  FIG. 5  is a perspective view showing a configuration of the printed board  5  and the tab terminals  6 . The printed board  5  is a substantial rectangular plate member made of electrically insulating material. Cut-out portions  50  are respectively provided on the right and left side faces of the printed board  5 . The tab terminals  6  (a coil tab terminal  6   a  and a contact tab terminal  6   b ) are composed of an electrical conductive plate member. A pair of connecting portions  6   c  for connecting to the printed board  5  is formed at the lower end portion of each tab terminal  6 . A pair of coil tab terminals  6   a  are arranged at the rear end portion of the printed board  5 , opposed to each other. A pair of contact tab terminals  6   b  are arranged at the front end portion of the printed board  5  on the same straight line in the right-left direction. 
     A plurality of through-holes for connecting to terminals are provided at the printed board  5 . In this case, given that the printed board  5  is divided into two regions  5 L and  5 R corresponding to the right and left electromagnetic relay bodies  4 , the left region  5 L of the printed board  5  includes a pair of through-holes  51  corresponding to the positions of the coil terminals  25 ; a through-hole  53  corresponding to the position of the terminal  35 ; a through-hole  55  corresponding to the position of the terminal  36 ; a pair of through-holes  57  corresponding to the positions of the connecting portions  6   c  of the coil tab terminal  6   a ; and a pair of through-holes  59  corresponding to the positions of the connecting portions  6   c  of the contact tab terminal  6   b . In this case, the pair of through-holes  57  are provided between the pair of through-holes  51 , and close to the left through-hole  51 . The pair of through-holes  59  are provided in front of the through-hole  55 , and close to the through-hole  55 . 
     In the same manner, the right region  5 R of the printed board  5  includes a pair of through-holes  52  corresponding to the positions of the coil terminals  25 ; a through-hole  54  corresponding to the position of the terminal  35 ; a through-hole  56  corresponding to the position of the terminal  36 ; a pair of through-holes  58  corresponding to the positions of the connecting portions  6   c  of the coil tab terminal  6   a ; and a pair of through-holes  60  corresponding to the positions of the connecting portions  6   c  of the contact tab terminal  6   b . In this case, the pair of through-holes  58  are provided between the pair of through-holes  52 , and close to the right through-hole  52 . The pair of through-holes  60  are provided in front of the through-hole  56 , and close to the through-hole  56 . 
     Corresponding to these through-holes  51  to  60 , a predetermined circuit pattern is formed on an upper face of the printed board  5  by an electrical conductive body. The predetermined circuit pattern includes an electrical conductive portion  61  containing the left through-hole  51  and the pair of through-holes  57 ; an electrical conductive portion  62  containing the right through-hole  52  and the pair of through-holes  58 ; an electrical conductive portion  63  containing the through-hole  55  and the pair of through-holes  59 ; an electrical conductive portion  64  containing the through-hole  56  and the pair of through-holes  60 ; an electrical conductive portion  65  containing the right through-hole  51  and the left through-hole  52 ; and an electrical conductive portion  66  containing the through-hole  53  and the through-hole  54 . In this case, the electrical conductive portion  66  is formed into a pattern bent backward so as to be separate from the electrical conductive portion  64 . 
     When the printed board  5  is accommodated in the housing  2 , the tab terminals  6  are previously soldered onto the printed board  5 . That is, the connecting portions  6   c  of the tab terminals  6  are respectively inserted into the through-holes  57  to  60  and soldered onto the printed board  5 . After that, the printed board  5  integrated with the tab terminals  6  is accommodated in the housing  2 . Under the condition that the printed board  5  is accommodated, a lower face of the printed board  5  comes into contact with the step portion  203  on the front and rear inner side faces of the housing  2 . Therefore, the printed board  5  is supported in the housing  2  which is separate from the base portion  10 . At this time, the coil terminals  25  penetrate the through-holes  51  and  52  of the printed board  5 , the terminals  35  penetrate the through-holes  53  and  54 , and the terminals  36  penetrate the through-holes  55  and  56 . As a result, these terminals  25 ,  35  and  36  protrude from an upper face of the printed board  5 . 
     The terminals  25 ,  35  and  36  protruding from the printed board  5  are soldered to the electrical conductive portions  61  to  66  to form the terminal connecting circuit. After that, the cover  3  is attached to an upper portion of the housing  2 . At this time, the tab terminals  6  penetrate the slit holes  301  formed on the cover  3 , and the protruding portions  302  of the cover  3  pass through the cut-out portions  50  of the printed board  5  and are inserted into the through-holes  205  of the housing  2 . In this way, assembling of the electromagnetic relay (shown in  FIG. 1 ) is completed. As a result, electric parts such as a printed board are connected to the tab terminals  6  of the completed electromagnetic relay. 
     A principal action of the electromagnetic relay according to the present embodiment will be explained below.  FIG. 6  is a view in which the electromagnetic relay assembling body  1  (shown in  FIG. 2 ) accommodated in the housing  2  is viewed from above. In the view, reference marks  51   a  to  60   a  are the soldered portions (the terminal connecting portions) of the terminals in the through-holes  51  to  60 . When the electromagnetic relay is in a non-active state, electric current does not flow through the coil tab terminals  6   a , and therefore, the coil  21  of the electromagnet  23  is put into a non-excited state. Accordingly, the movable contact  33  is set at the initial position and separated from the fixed contact  34 , so that a flow of an electric current to the contact tab terminals  6   b  is shut off. 
     When the electromagnetic relay is put into an active state, an electric current flows from one of the coil tab terminals  6   a , for example, from the left coil tab terminal  6   a  to the electrical conductive portion  61  of the printed board  5 , the left side coil  21 , the electrical conductive portion  65 , the right side coil  21 , the electrical conductive portion  62  and the other (the right) coil tab terminal  6   a  in this order. That is, the electric current flows to the right and left coils  21  in series. Thus, the right and left coils  21  are respectively excited, and each armature  24  is attracted to the iron core  22  of the electromagnet  23 , and therefore, the right and left movable contacts  33  are respectively in contact with the fixed contacts  34 . 
     As a result, an electric current flows from one of the contact tab terminals  6   b , for example, from the left contact tab terminal  6   b  to the electrical conductive portion  63  of the printed board  5 , the fixed contact  34  of the left side electromagnetic relay body  4 , the movable contact  33  coming into contact with the fixed contact  34 , the electrical conductive portion  66 , the movable contact  33  of the right side electromagnetic relay body  4 , the fixed contact  34  coming into contact with the movable contact  33 , the electrical conductive portion  64  and the other (the right side) contact tab terminal  6   b  in this order. That is, the electric current flows to the contacts  33 ,  34  of the right and left electromagnetic relay bodies  4  in series. 
     In the present embodiment, when the setting of the circuit pattern of the printed board  5  is changed, an arrangement of the tab terminals  6  can be easily changed without changing the configuration of the electromagnetic relay body  4 . This matter will be explained below. 
       FIG. 7  is a view showing a variation (a first variation) of  FIG. 6  in which the arrangement of the tab terminals  6  is changed. In  FIG. 7 , the terminal connecting portions  57   a  and  58   a  of the right and left coil tab terminals  6   a  are respectively located in front of the terminal connecting portions  51   a  and  52   a , the terminal connecting portions  59   a  of the left contact tab terminal  6   b  is located on the right side of the terminal connecting portion  55   a , and the terminal connecting portions  60   a  of the right contact tab terminal  6   b  is located in front of the terminal connecting portion  54   a . Positions of the terminal connecting portions  51   a  to  56   a  of the coil terminals  25 , the terminals  35  and the terminals  36  are the same as those shown in  FIG. 6 . 
     The electrical conductive portion  71  in  FIG. 7  connects the left terminal connecting portion  51   a  with the pair of terminal connecting portions  57   a , the electrical conductive portion  72  connects the right terminal connecting portion  52   a  with the pair of terminal connecting portions  58   a , the electrical conductive portion  73  connects the terminal connecting portion  55   a  with the pair of terminal connecting portions  59   a  and the electrical conductive portion  75  connects the right side terminal connecting portion  51   a  with the left side terminal connecting portion  52   a . That is, the fundamental configuration of the electrical conductive portions  71 ,  72 ,  73  and  75  is the same as that of the electrical conductive portions  61 ,  62 ,  63  and  65  shown in  FIG. 6 . 
     On the other hand, the electrical conductive portion  74  connects the terminal connecting portion  54   a  with the pair of terminal connecting portions  60   a , and the electrical conductive portion  76  connects the terminal connecting portion  53   a  with the terminal connecting portion  56   a . Thus, in the same manner as that shown in  FIG. 6 , the circuit is formed, in which the right and left coils  21  are connected to each other in series through the printed board  5  and the contacts  33  and  34  of the right and left electromagnetic relay bodies  4  are connected to each other in series. 
     According to the present embodiment, the following operational effects can be exhibited. 
     (1) The terminal connecting circuit is formed on the printed board  5 , in such a manner that the connecting portions  6   c  of the tab terminals  6  are connected to the printed board  5  and that four coil terminals  25 , a pair of terminals  35  for movable contacts  33  and a pair of terminals  36  for fixed contacts  34  are respectively connected to the printed board  5 . Therefore, in the electromagnetic relay including a plurality of coil terminals  25 , terminals  35  and terminals  36 , the arrangement of the tab terminals  6  can be easily changed as shown in  FIGS. 6 and 7  without changing the configuration of the electromagnetic relay body  4 . 
     (2) The terminals  35  and terminals  36  of a pair of electromagnetic relay bodies  4  are connected to each other in series through the printed board  5 . Therefore, a contact gap can be increased. 
     (3) The terminal arrangement can be changed by using the tab terminals  6  of the same profile without changing the profile of the tab terminal  6 . Therefore, the number of parts can be prevented from increasing. 
     (4) The electromagnetic relay body  4  is supported by the housing  2 , in such a manner that the base portion  10  of the electromagnetic relay body  4  is contacted with the step portion  202  of the housing  2  and the protruding portion  12  of the base portion  10  is inserted into the through-hole  204  of the housing  2 . Therefore, it can be prevented that a load due to a gravity of the coil  21  or the like is applied to the terminal connecting portion of the printed board  5 . 
     (5) By using the protruding portions  12  and the through-holes  204 , the electromagnetic relay body  4  can be easily fixed to the housing  2  without using a means of adhesion or the like. 
     (6) After a pair of electromagnetic relay bodies  4  are accommodated in the housing  2 , the printed board  5 , onto which the tab terminals  6  are previously fixed, is placed above the electromagnetic relay body  4 . Furthermore, under the condition that the coil terminals  25 , the terminals  35  and the terminals  36  are protruded from the printed board  5 , the terminals  25 ,  35  and  36  are soldered onto the printed board  5 . Accordingly, the electromagnetic relay can be easily assembled. 
     In the above embodiment, the terminals  35  (a first movable contact member and a second movable contact member) of a pair of movable contact plate members  31  and the terminals  36  (a first fixed contact member and a second fixed contact member) of a pair of fixed contact plate members  32  are respectively electrically connected to the printed board  5 , and a pair of contact tab terminals  6   b  (a first contact terminal member and a second contact terminal member) are electrically connected to the printed board  5 . Furthermore, the circuit is formed, in such a manner that the fixed contact  34  (a first fixed contact) of one (for example, on the left side) of the fixed contact members  32 , the movable contact  33  (a first movable contact) of one of the movable contact plate members  31 , the movable contact  33  (a second movable contact) of the other movable contact plate member  31  and the fixed contact  34  (a second fixed contact) of the other fixed contact member  32  are connected to each other in series. However, the configuration of the terminal connecting circuit is not limited to the embodiment described above. 
       FIG. 8  is a view showing a variation (a second variation of  FIG. 6 ) of the terminal connecting circuit. When  FIG. 8  is compared with  FIG. 6 , in the configuration shown in  FIG. 8 , a pair of terminal connecting portions  60   a  of the contact tab terminals  6   b  are located at the middle in the right-left direction of the terminal connecting portions  53   a  and  54   a , and at a little rearward position of the terminal connecting portions  53   a  and  54   a . The electrical conductive portions  81 ,  82  and  85  shown in  FIG. 8  are formed in the same manner as that of the electrical conductive portions  61 ,  62  and  65  shown in  FIG. 6 . On the other hand, in the electrical conductive portion  83 , the terminal connecting portions  55   a  and  56   a  to which the right and left terminals  36  are connected and a pair of terminal connecting portions  59   a  of the contact tab terminal  6   b  are connected to each other. In the electrical conductive portion  84 , the terminal connecting portions  53   a  and  54   a  to which the right and left terminals  35  are connected and a pair of terminal connecting portions  60   a  of the contact tab terminal  6   b  are connected to each other. 
     Therefore, when the electromagnetic relay is put into the active state, an electric current flows from one (for example, the left side) of the contact tab terminals  6   b  to the electrical conductive portion  83  of the printed board  5 , the fixed contacts  34  of the right and left electromagnetic relay bodies  4 , the movable contacts  33 , the electrical conductive portion  84  and the other (the right side) contact tab terminal  6   b  in this order. That is, the electric current flows to the contacts  33  and  34  of the right and left electromagnetic relay bodies  4  in parallel. In this way, when a parallel circuit is formed through the printed board  5 , it is possible to increase an electrifying capacity of the contact. 
     In  FIG. 6 , the circuit is formed, in such a manner that a pair of coils  21  (a first coil section and a second coil section) are electrically connected to the printed board  5  through the coil terminals  25 , and a pair of coil tab terminals  6   a  (a first coil terminal member and a second coil terminal member) are electrically connected to the printed board  5 , so that a pair of coils  21  are connected to each other in series by the printed board  5 . However, the configuration of the circuit is not limited to the embodiment described above. 
       FIG. 9  is a view showing a variation example (a third variation example of  FIG. 6 ) of the terminal connecting circuit. When  FIG. 9  is compared with  FIG. 6 , in  FIG. 9 , a pair of terminal connecting portions  57   a  of one of the coil tab terminals  6   a  are arranged close to the right terminal connecting portion  51   a  between the right and left terminal connecting portions  51   a . The electrical conductive portions  93 ,  94  and  96  shown in  FIG. 9  are respectively formed in the same manner as the electrical conductive portions  63 ,  64  and  66  shown in  FIG. 6 . On the other hand, in the electrical conductive portion  91 , the terminal connecting portion  51   a  to which the left coil terminal  25  of the left electromagnetic relay body  4  is connected, the terminal connecting portion  52   a  to which the right coil terminal  25  of the right electromagnetic relay body  4  is connected, and the terminal connecting portions  58   a  of the coil tab terminal  6   a  are connected to each other. In the electrical conductive portion  95 , the terminal connecting portion  51   a  to which the right coil terminal  25  of the left electromagnetic relay body  4  is connected, the terminal connecting portion  52   a  to which the left coil terminal  25  of the right electromagnetic relay body  4  is connected, and the terminal connecting portions  57   a  of the coil tab terminal  6   a  are connected to each other. 
     As a result, when the electromagnetic relay is put into an active state, an electric current flows from one (for example, the left) of the coil tab terminals  6   a  to the electrical conductive portion  95  of the printed board  5 , the right and left coils  21 , the electrical conductive portion  91  and the other (the right) coil tab terminal  6   a  in this order. That is, the electric current flows in the right and left coils  21  in parallel. 
     In order to shut off arc discharge generated when the electromagnetic relay is put into a non-active state, a permanent magnet may be provided close to the contacts  33  and  34 .  FIG. 10  is a view showing an example of the arrangement of the permanent magnet. In  FIG. 10 , a pair of substantially rectangular through-holes  208  are opened in the bottom portion of the housing  2  and the permanent magnet  209  is attached to each through-hole  208 . Therefore, in a state in which the electromagnetic relay assembling body  1  is accommodated in the housing  2 , the permanent magnet  209  is located below each contact  33  and  34  as shown in the drawing. The magnet  209  generates a magnetic force in a direction (the up-down direction) perpendicular to the direction (the front-rear direction) in which the movable contact  33  and the fixed contact  34  are opposed to each other. Therefore, it is easy to shut off an arc discharge generated between the contacts  33  and  34 . 
     In the embodiment described above, a pair of electromagnetic relay bodies  4  are accommodated in the housing  2  and electrically connected to each other through the printed board  5 . However, not less than three electromagnetic relay bodies  4  may be electrically connected to each other through the printed board  5 , and the number of the terminals  25 ,  35  and  36  connected to each other through the printed board  5  is not limited to the embodiment described above. The protruding portion  12  of the base portion  10  is inserted into the through-hole  204  of the housing  2  so as to support the base portion  10  (base member). However, the configuration of the support portion is not limited to the embodiment described above. 
     According to the present invention, a plurality of fixed contact members, a plurality of movable contact members and a plurality of contact terminal members are respectively connected to the printed board, so that at least one of the fixed contact members and the movable contact members can be connected to the contact terminal members through the printed board. Therefore, an arrangement of the terminal members can be easily changed. 
     While the present invention has been described with reference to the preferred embodiments thereof, it will be understood, by those skilled in the art, that various modifications and changes may be made thereto without departing from the scope of the appended claims.