Patent Publication Number: US-6982393-B2

Title: Lever fitting-type power supply circuit breaker

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a lever fitting-type power supply circuit breaker which fits one of connector housings to the other connector housing and releases such fitting on the contrary by operating a lever with low operating force by utilizing a cam mechanism. 
   2. Description of the Related Art 
   In an electric vehicle, a capacity of a power supply which is a battery is larger as compared with that of a battery of a usual gasoline engine vehicle and the like. Accordingly, in such a case of maintaining an electrical system and the like of the electric vehicle, a power supply circuit is opened by a circuit breaker, and safety during work is ensured. As such a type of the conventional lever fitting-type power supply circuit breaker, there is one shown in FIGS. 1A to 13 (Japanese Patent Application Laid-Open No. 2002-343169). 
   As shown in  FIGS. 10 to 13 , this lever fitting-type power supply circuit breaker  100  includes one connector housing  101 , a lever  102  attached to the one connector housing  101 , and the other connector housing  103  to which the one connector housing  101  is attached by an operation of the lever  102 . 
   As shown in  FIGS. 1A ,  1 B, and  4  to  6 B, the one connector housing  101  includes a housing body  104 , and a cover  105  attached to the housing body  104  so as to close an upper portion of the housing body  104 . A terminal hood portion  108  is provided under the housing body  104 , and a pair of male terminals  109  and  109  (shown in  FIGS. 5 and 6B ) are provided in the terminal hood portion  108  in a state of being protruded downward. The pair of male terminals  109  and  109  are electrically connected to each other through a fuse  110  (shown in  FIG. 6A ) housed in the housing body  104 . 
   A pair of guide pins  111  and  111  are protruded from outer walls of the housing body  104 , and guide grooves  120  of the lever  102 , which are described later, are individually engaged with the guide pins  111  and  111 . 
   A pair of lever-path adjusting guide grooves  115  and  115  are provided on the outer walls of the housing body  104 . One of step side faces (denoted by reference numeral  115   a ) forming the respective lever-path adjusting guide grooves  115  and  115  is formed of a vertical step side face extended in a vertical direction, a horizontal step side face extended in a horizontal direction, and a circular arc step side face connecting these side faces in a circular arc shape. Then, with the pair of lever-path adjusting guide grooves  115  and  115 , a pair of lever-path adjusting guide pins  124  and  124  of the other connector housing  103 , which are described later, are engaged. Each of the pair of lever-path adjusting guide pins  124  and  124  is slid along the step side face  115   a  of each lever-path adjusting guide groove  115 . 
   As shown in  FIGS. 2 to 6B , the lever  102  includes a pair of arm plate portions  118   a  and  118   b  arranged in parallel at an interval, and an operating portion  119  coupling the pair of arm plate portions  118   a  and  118   b  to each other. In the pair of arm plate portions  118   a  and  118   b , the guide grooves  120  extended in the horizontal direction are provided at positions symmetric to each other. Into the respective guide grooves  120 , the pair of guide pins  111  and  111  of the one connector housing  101  are individually inserted. 
   In the pair of arm plate portions  118   a  and  118   b , cam grooves  121  are provided at positions symmetric to each other. Into the pair of cam grooves  121  and  121 , cam pins  136  of the other connector housing  103 , which are described later, are inserted. Moreover, the lever-path adjusting guide pins  124  are individually provided on inner walls of the pair of arm plate portions  118   a  and  118   b . The pair of lever-path adjusting guide pins  124  and  124  are engaged with the pair of lever-path adjusting guide grooves  115  and  115  of the one connector housing  101 . 
   Moreover, one of the pair of arm plate portions  118   a  and  118   b  is provided to be wider in width as compared with the other one. Specifically, the arm plate portion  118   b  is made wider. In the arm plate portion  118   b  wider in width, a connector portion  125  (shown in  FIGS. 3A and 6B ) is provided. In the connector portion  125 , a fitting sensing male terminal  126  is provided. 
   As shown in  FIGS. 7 ,  8 A,  8 B and the like, the other connector housing  103  has a substantially rectangular shape in which an upper surface is opened, and an inner space thereof serves as an attachment space  130  of the one connector housing  101 . On a bottom surface portion  131  becoming a lower surface of the attachment space  130 , terminal hood/housing portions  134  are integrally provided in a state of being protruded in the vertical direction. In the terminal hood/housing portions  134 , female terminals  135  (shown in  FIGS. 7 ,  8 A and  8 B) are individually housed. To the respective female terminals  135 , one end sides of lead wires  139   a  are connected. One of the lead wires  139   a  and the other thereof are guided to a load unit  140  side of a power supply circuit B and a power supply unit  141  side of the power supply circuit B, respectively. Specifically, a power switch SW 1  (shown in  FIG. 9 ) of the power supply circuit B is composed of the male terminals  109  and female terminals  135  of both of the connector housings  101  and  103 . 
   Moreover, from the symmetric positions of inner peripheral walls of the other connector housing  103 , the pair of cam pins  136  and  136  are protruded. As described above, the pair of cam pins  136  and  136  are inserted into the cam grooves  121  of the lever  102  when the one connector housing  101  is attached to the other connector housing  103 . Moreover, in the attachment space  130  of the other connector housing  103 , a connector portion  137  is provided. In the connector portion  137 , a pair of fitting sensing female terminals  138  and  138  are arranged. A fitting sensing switch SW 2  (shown in  FIG. 9 ) is composed of the pair of fitting sensing female terminals  138  and  138  and the fitting sensing male terminal  126  of the lever  102 . The fitting sensing switch SW 2  is turned ON in a manner that the male terminal  126  of the lever  2  is brought into contact with the pair of fitting sensing female terminals  138  and  138 , and turned OFF in a non-contact state of the male terminal  126  of the lever  102 . To the pair of female terminals  138  and  138 , lead wires  139   b  are individually connected, and both of the lead wires  139   b  are guided to a relay circuit  142  of the power supply circuit B. 
   Next, the power supply circuit B is described. As shown in  FIG. 9 , the power supply circuit B includes the load unit  140 , and the power supply unit  141  which supplies electric power to the load unit  140 . To the load unit  140  and the power supply unit  141 , the power switch SW 1 , which is formed of the terminals  109  and  135  of both of the connector housings  101  and  103 , and the relay circuit  142 , are connected in series. The relay circuit  142  is an electric circuit which is turned ON when the fitting sensing switch SW 2  is ON and turned OFF when the fitting sensing switch SW 2  is OFF. The power switch SW 1  formed of the terminals  109  and  135  of both of the connector housings  101  and  103  is a mechanical switch as described above. 
   Next, an operation of the lever fitting-type power supply circuit breaker  100  is described with reference to  FIGS. 10 to 13 .  FIG. 10  is a perspective view showing a state before the one connector housing  101  is temporarily fitted to the other connector housing  103 .  FIG. 11  is a perspective view showing a state where the one connector housing  101  is set at a temporal connector-fitting position of the other connector housing  103 .  FIG. 12  is a perspective view showing a state where the lever  102  is located at a rotation completing position in a process where the one connector housing  101  is fitted to the other connector housing  103 .  FIG. 13  is a perspective view showing a state where the fitting of the one connector housing  101  to the other connector housing  103  is completed. 
   First, an operation of bringing the power supply circuit B into a conductive state by the lever fitting-type power supply circuit breaker  100  is described. As shown in  FIG. 10 , the lever  102  is set at an operation start position, and the one connector housing  101  is inserted into the attachment space  103  from above the other connector housing  103 . Then, as shown in  FIG. 11 , the terminal hood portion  108  of the one connector housing  101  is inserted into the terminal hood/housing portion  134  of the other connector housing  103  while being fitted thereto. Moreover, the pair of cam pins  136  and  136  of the other connector housing  103  are inserted into the pair of cam grooves  121  and  121  of the lever  102 . Then, the pair of cam pins  136  and  136  enter the pair of cam grooves  121  and  121 , and the one connector housing  101  and the other connector housing  103  are set at the temporal connector-fitting position. 
   Next, the lever  102  is rotated in a direction of an arrow A 1  of  FIG. 11 . Then, the lever  102  is rotated about the pair of guide pins  111  and  111  from the operation start position of  FIG. 11  to a rotation completion position of  FIG. 12 . By this rotation of the lever  102 , the one connector housing  101  gradually approaches and enters the inside of the other connector housing  103 . Then, the terminals  109  and  135  of both of the connector housings  101  and  103  are brought into contact with each other before the lever  102  is located at the rotation completion position, and at the rotation completion position of the lever  102 , both of the connector housings  101  and  103  reach the connector-fitting position. 
   Next, when the lever  102  is slid in a direction of an arrow B 1  of  FIG. 12 , the pair of guide pins  111  and  111  are slid in the pair of guide grooves  120  and  120  of the lever  102 . In addition, the pair of cam pins  136  and  136  of the other connector housing  103  are slid in the pair of cam grooves  121  and  121  of the lever  102 , and are located at a fitting completion position of  FIG. 13 . In this sliding process, the fitting sensing male terminal  126  of the lever  102  is brought into contact with the fitting sensing female terminals  138  and  138 . Then, when the fitting sensing switch SW 2  is turned ON, the relay circuit  142  is turned ON, and thus the power supply circuit B is brought into the conductive state for the first time. 
   Next, an operation of bringing the power supply circuit B in the conductive state into a non-conductive state (break of the power supply) by the lever fitting-type power supply circuit breaker  100  is described. In the state of  FIG. 13 , when the lever  102  located at the operation completion position is slid in a direction of an arrow B 2  of  FIG. 13 , the pair of guide pins  111  and  111  are slid in the pair of guide grooves  120  and  120  of the lever  102 , and the pair of cam pins  136  and  136  of the other connector housing  103  are slid in the pair of cam grooves  121  and  121  of the lever  102 . Thus, the lever  102  is slid to the rotation completion position of  FIG. 12 . Before the lever  102  is located at the rotation completion position, the fitting sensing male terminal  126  of the lever  102  is separated from the pair of fitting sensing female terminals  138  and  138  of the other connector housing  103 , and is brought into the non-contact state therewith. Then, when the fitting sensing switch SW 2  is turned OFF, the relay circuit  142  is turned OFF, and at this point of time, the power supply circuit B has already been brought into the non-conductive state. 
   Next, when the lever  102  is rotated in a direction of an arrow A 2  of  FIG. 12 , the lever  102  is rotated about the pair of guide pins  111  and  111  of the lever  102  to the operation start position of  FIG. 11 . Moreover, the pair of cam pins  136  and  136  of the other connector housing  103  are moved in the pair of cam grooves  121  and  121  of the lever  102 , and thus the one connector housing  101  is gradually moved upward so as to be separated from the other connector housing  103 , and is drawn therefrom. Then, before the lever  102  is located at the operation start position, the terminals  109  and  135  of both of the connector housings  101  and  103  are brought into the non-contact state with each other, and at the operation start position of the lever  102 , both of the connector housings  101  and  103  are located at the temporal connector-fitting position. 
   As described above, in the lever fitting-type power supply circuit breaker  100 , in the process of rotationally moving the lever  102  from the operation start position to the rotation completion position, the terminals  109  and  135  of both of the connector housings  101  and  103  are brought into the contact state with each other, and the power switch SW 1  is tuned ON, but the power supply circuit B is still non-conductive. In the process of sliding (linearly moving) the lever  102  from the rotation completion position to the operation completion position, the fitting sensing switch SW 2  is turned ON, and thus the relay circuit  142  is turned ON, and the power supply circuit B is brought into the conductive state for the first time. Therefore, the power supply circuit B can be prevented from being brought into the conductive state halfway through the operation of the lever  102 . Hence, recognition that the power supply circuit B is still non-conductive because the operation of the lever  102  is not completed yet becomes reasonable, thus making it possible to prevent an occurrence of an accident. Moreover, when the power supply circuit B is switched from the conductive state to the non-conductive state, in the process of linearly moving the lever  102  from the operation completion position to the rotation completion position, the fitting sensing switch SW 2  is turned OFF, and thus the relay circuit  142  is turned OFF, and the power supply circuit B is brought into the non-conductive state. In the process of rotationally moving the lever  102  from the rotation completion position to the operation start position, the power switch SW 1  between both of the terminals  109  and  135  is brought into a separated state. Thus, there is a time lag from the time when the power supply circuit B is turned OFF to the time when the power switch SW 1  between the terminals  109  and  135  is separated, and a discharge time is ensured. Therefore, an arc discharge can be prevented. 
   However, in the above-described conventional lever fitting-type power supply circuit breaker  100 , the fitting sensing switch SW 2  is formed into a so-called male-female terminal structure made of the fitting sensing male terminal  126  and the pair of fitting sensing female terminals  138  and  138 , and is arranged in the connector portions  125  and  137 , and accordingly, a large installation space is required. Therefore, there are problems that a width dimension W 1  of the lever  102  and a width dimension of W 2  of the other connector housing  103  are increased, and that the lever fitting-type power supply circuit breaker  100  becomes large. 
   SUMMARY OF THE INVENTION 
   In this connection, the present invention is one created in order to solve the above-described problems. It is an object of the present invention to provide a lever fitting-type power supply circuit breaker including a power switch and a fitting sensing switch, which is capable of being downsized. 
   In order to achieve the above-described object, the present invention is a lever fitting-type power supply circuit breaker, including: 
   a first connector housing including a lever provided for moving between an operation start position and an operation completion position; and 
   a second connector housing fittable to the first connector housing, 
   wherein the first and second connector housings individually provide power terminals forming a power switch therein, 
   fitting sensing terminals forming a fitting sensing switch are individually provided in the lever and the second connector housing, the fitting sensing terminal provided in the second connector housing is formed of a pair of male terminals, and the fitting sensing terminal provided in the lever is formed of a short pin, and 
   when the lever is operated from the operation start position to the operation completion position in a state where the first and second connector housings are set at a temporal connector-fitting position, the first and second connector housings move from the temporal connector-fitting position to a connector-fitting position, and the power terminals are brought into contact with each other to turn ON the power switch, and thereafter, both of the fitting sensing terminals are brought into contact with each other to turn ON the fitting sensing switch, and a power supply circuit is brought into a conductive state by the turning ON of the fitting sensing switch. 
   With this configuration, the fitting sensing switch is composed of the pair of male terminals and the short pin, which can accordingly be installed in small installation spaces of the other connector housing and the lever, respectively. Hence, the other connector housing and the lever can be downsized, and eventually, the lever fitting-type power supply circuit breaker can be downsized. Moreover, a structure of the fitting sensing switch is simple, and accordingly, the fitting sensing switch can be manufactured at low cost. 
   In a preferred embodiment, the pair of male terminals may be formed by utilizing a pair of bus bars arranged in the second connector housing, the short pin may be formed into a substantially U-shape, and the short pin may sandwich the pair of male terminals from both outsides thereof to be brought into a conductive state thereto. 
   With this configuration, the short pin of the substantially U-shape sandwiches the pair of male terminals to contact the same male terminals, and accordingly, the short pin can be brought into contact with the male terminals with large pressing force. Therefore, a highly reliable conductive state can be obtained. 
   The lever may include a pair of arm plate portions arranged at an interval and an operating portion coupling the pair of arm plate portions to each other, and the short pin may be provided in the operating portion. 
   With this configuration, the short pin can be installed without increasing a width of the lever. 
   The movement of the lever from the operation start position to the operation completion position may be composed of a rotational movement and a linear movement, both of the power terminals may be brought into contact with each other in a process of the rotational movement, and the pair of male terminals and the short pin may be brought into contact with each other in a process of the linear movement. 
   With this configuration, an operation of the lever, which makes the power supply circuit conductive, is composed of two actions, which are the rotational operation and the linear operation, and the power supply circuit is made conductive by the latter linear operation. Moreover, an operation of the lever, which makes the power supply circuit non-conductive, is composed of the two actions performed reversely to the above, the power supply circuit is turned OFF by the former linear operation, and the power switch between the power terminals is turned OFF with delay by the following rotational operation. Therefore, a sufficient discharge time can be ensured. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIGS. 1A and 1B  show a conventional example:  FIG. 1A  is an exploded front view of one connector housing, and  FIG. 1B  is an exploded side view of the one connector housing. 
       FIG. 2  shows the conventional example, and is a perspective view of a lever. 
       FIGS. 3A and 3B  show the conventional example:  FIG. 3A  is a side view of the lever, and  FIG. 3B  is a cross-sectional view along a line  3 B— 3 B in  FIG. 3A . 
       FIG. 4  shows the conventional example, and is a front view showing the one connector housing to which the lever is attached, in a state where the lever is located at an operation start position. 
       FIG. 5  shows the conventional example, and is a back view of the one connector housing to which the lever is attached, in a state where the lever is located at a rotation start position. 
       FIGS. 6A and 6B  show the conventional example:  FIG. 6A  is a partially cutaway plan view of the one connector housing to which the lever is attached, and  FIG. 6B  is a bottom view of the one connector housing to which the lever is attached. 
       FIG. 7  shows the conventional example, and is a partially cutaway front view of the other connector housing. 
       FIGS. 8A and 8B  show the conventional example:  FIG. 8A  is a plan view of the other connector housing, and  FIG. 8B  is a cross-sectional view along a line  8 B— 8 B in  FIG. 8A . 
       FIG. 9  shows the conventional example, and is a circuit diagram of a power supply circuit. 
       FIG. 10  shows the conventional example, and is a perspective view showing a state before the one connector housing is temporarily fitted to the other connector housing. 
       FIG. 11  shows the conventional example, and is a perspective view showing a state where the one connector housing is temporarily fitted to the other connector housing and the lever is located at the operation start position. 
       FIG. 12  shows the conventional example, and is a perspective view showing a state where one connector housing is fitted to the other connector housing and the lever is located at a rotation completion position. 
       FIG. 13  shows the conventional example, and is a perspective view showing a state where the one connector housing is fitted to the other connector housing and the lever is located at an operation completion position. 
       FIGS. 14A and 14B  show one embodiment of the present invention:  FIG. 14A  is an exploded front view of one connector housing, and  FIG. 14B  is an exploded side view of the one connector housing. 
       FIG. 15  shows the one embodiment of the present invention, and is a perspective view of a lever. 
       FIGS. 16A and 16B  show the one embodiment of the present invention:  FIG. 16A  is a side view of the lever, and  FIG. 16B  is a cross-sectional view along a line  16 B— 16 B of  FIG. 16A . 
       FIG. 17  shows the one embodiment of the present invention, and is a front view showing the one connector housing to which the lever is attached, in a state where the lever is located at a rotation start position. 
       FIG. 18  shows the one embodiment of the present invention, and is a back view showing the one connector housing to which the lever is attached, in the state where the lever is located at the rotation start position. 
       FIGS. 19A and 19B  show the one embodiment of the present invention:  FIG. 19A  is a partially cutaway plan view of the one connector housing to which the lever is attached, and  FIG. 19B  is a bottom view of the one connector housing to which the lever is attached. 
       FIG. 20  shows the one embodiment of the present invention, and is a partially cutaway plan view of the other connector housing. 
       FIGS. 21A and 21B  show the one embodiment of the present invention:  FIG. 21A  is a plan view of the other connector housing, and  FIG. 21B  is a cross-sectional view along a line  21 B— 21 B in  FIG. 21A . 
       FIG. 22  shows the one embodiment of the present invention, and is a circuit diagram of a power supply circuit. 
       FIG. 23  shows the one embodiment of the present invention, and is a perspective view showing a state before the one connector housing is temporarily fitted to the other connector housing. 
       FIG. 24  shows the one embodiment of the present invention, and is a perspective view showing a temporal connector-fitting position in a process of attaching the one connector housing to the other connector housing in a state where the lever is located at an operation start position. 
       FIG. 25  shows the one embodiment of the present invention, and is a partially cutaway front view showing the temporal connector-fitting position in the process of attaching the one connector housing to the other connector housing in the state where the lever is located at the operation start position. 
       FIG. 26  shows the one embodiment of the present invention, and is a cross-sectional view showing the temporal connector-fitting position in the process of attaching the one connector housing to the other connector housing, in which the lever located at the operation start position is omitted. 
       FIG. 27  shows the one embodiment of the present invention, and is a perspective view showing the connector-fitting position in the process of attaching the one connector housing to the other connector housing in a state where the lever is located at a rotation completion position. 
       FIG. 28  shows the one embodiment of the present invention, and is a perspective view showing a state where the attachment of the one connector housing to the other connector housing is completed, that is, the connector fitting position in a state where the lever is located at an operation completion position. 
       FIGS. 29A ,  29 B and  29 C show the one embodiment of the present invention:  FIG. 29A  is a front view showing a state where the lever is located between the operation start position and the rotation completion position, explaining a moving process of cam pins when the one connector housing is attached to the other connector housing;  FIG. 29B  is a front view showing a state where the lever is located at the rotation completion position, explaining the moving process of the cam pins when the one connector housing is attached to the other connector housing; and  FIG. 29C  is a front view showing a state where the lever is located at the operation completion position, explaining the moving process of the cam pins when the one connector housing is attached to the other connector housing. 
       FIGS. 30A ,  30 B and  30 C show the one embodiment of the present invention:  FIG. 30A  is a front view showing a state where the lever is located between the operation start position and the rotation completion position, explaining a moving process of lever-path adjusting guide pins when the one connector housing is attached to the other connector housing;  FIG. 30B  is a front view showing a state where the lever is located at the rotation completion position, explaining the moving process of the lever-path adjusting guide pins when the one connector housing is attached to the other connector housing; and  FIG. 30C  is a front view showing a state where the lever is located at the operation completion position, explaining the moving process of the lever-path adjusting guide pins when the one connector housing is attached to the other connector housing. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
   One embodiment of the present invention is described below with reference to the drawings. 
     FIGS. 14A to 30C  show a lever fitting-type power supply circuit breaker of the one embodiment of the present invention.  FIG. 14A  is an exploded front view of one connector housing.  FIG. 14B  is an exploded side view of the one connector housing.  FIG. 15  is a perspective view of a lever.  FIG. 16A  is a side view of the lever.  FIG. 16B  is a cross-sectional view along a line  16 B— 16 B in  FIG. 16A .  FIG. 17  is a front view showing the one connector housing to which the lever is attached, in a state where the lever is located at an operation start position.  FIG. 18  is a back view showing the one connector housing to which the lever is attached, in the state where the lever is located at the operation start position.  FIG. 19A  is a partially cutaway plan view of the one connector housing to which the lever is attached.  FIG. 19B  is a bottom view of the one connector housing to which the lever is attached.  FIG. 20  is a partially cutaway front view of the other connector housing.  FIG. 21A  is a plan view of the other connector housing.  FIG. 21B  is a cross-sectional view along a line  21 B— 21 B in  FIG. 21A . 
   As shown in  FIGS. 23 to 28  and  1 A to  5 , a lever fitting-type power supply circuit breaker  1 A for a high-voltage/large-current circuit includes one connector housing  1  made of synthetic resin, a lever  2  made of synthetic resin, to which the one connector housing  1  is attached, and the other connector housing  3  made of synthetic resin, to which the one connector housing  1  is attached by an operation of the lever  2 . 
   As shown in  FIGS. 14A ,  14 B and  17  to  19 B, the one connector housing  1  includes a housing body  4 , and a cover  5  attached to the housing body  4  so as to close an upper portion of the housing body  4 . The cover  5  is attached to the housing body  4  in a manner that a pair of triangular protrusions (protruding portions)  6  and  6  of the housing body  4  are inserted into engaging holes  7  of the cover  5 . Each triangular protrusion  6  is provided such that a lower side thereof becomes a surface orthogonal to a surface of the housing body  4 , and that both of upper sides thereof become slant surfaces gradually rising from the surface of the housing body  4 . Thus, the cover  5  is made attachable to the housing body  4  in two directions, which are: from above the housing body  4  as shown by a solid line in  FIG. 14A , and from a side of the housing body  5  as shown by a virtual line in  FIG. 14A . Hence, in the case where the lever fitting-type power supply circuit breaker  1 A is installed in a narrow space, it is possible to easily attach and detach the cover  5 . 
   A terminal hood portion  8  is provided under the housing body  4 , and a pair of power male terminals (terminals for power)  9  and  9  shown in  FIGS. 18 and 19B  are provided in the terminal hood portion  8  in a state of being protruded downward. The pair of power male terminals  9  and  9  are electrically connected to each other through a fuse  10  which is shown in  FIGS. 19A and 4  and is housed in the housing body  4 . 
   A pair of guide pins  11  and  11  are protruded from outer walls of the housing body  4 , and each of the guide pins  11  and  11  has a substantially ellipsoidal shape obtained by cutting upper and lower ends of a circular cylinder shape. Specifically, long-width portions and short-width portions are composed. Then, guide grooves  20  of the lever  2 , which are described later, are individually engaged with the pair of guide pins  11  and  11 . 
   Moreover, a pair of substantially hemispherical engaging protrusions (convex portions)  12  and  12  are protruded from the outer walls of the housing body  4 , and each of the engaging protrusions  12  and  12  is provided on a flexible arm portion  14  formed between a pair of slits  13  and  13  of the outer wall of the housing body  4 . The pair of engaging protrusions  12  and  12  are ones which hold the lever  2  at a predetermined position by being inserted into first engaging holes  22  and second engaging holes  23  of the lever  2 , which are described later. Each engaging protrusion  12  is easily displaced in an inward direction of the housing body  4  due to an elastic flexible deformation of the flexible arm portion  14 . Furthermore, a pair of lever-path adjusting guide grooves  15  and  15  are provided on the outer walls of the housing body  4 . One of step side faces (denoted by reference numeral  15   a ) forming the respective lever-path adjusting guide grooves  15  and  15  is formed of a vertical step side face extended in a vertical direction, a horizontal step side face extended in a horizontal direction, and a circular arc step side face connecting these side faces in a circular arc shape. Then, with the pair of lever-path adjusting guide grooves  15  and  15 , a pair of lever-path adjusting guide pins  24  and  24  of the other connector housing  3 , which are described later, are engaged. The pair of lever-path adjusting guide pins  24  and  24  are slid along the step side faces  15   a  of the lever-path adjusting guide grooves  15 . 
   Moreover, a pair of lever rotation stopper portions  16  and  16  are protruded from the housing body  4 . The pair of lever rotation stopper portions  16  and  16  regulate rotation of the lever  2  such that the lever  2  is rotatable between an operation start position of  FIGS. 23 and 24 , where the lever  2  is erected vertically to the one connector housing  1 , and a rotation completion position of  FIG. 27 , where the lever  2  is set parallel to the one connector housing  1 . 
   As shown in  FIGS. 15 to 19B , the lever  2  includes a pair of arm plate portions  18   a  and  18   b  arranged in parallel at an interval, and an operating portion  19  coupling the pair of arm plate portions  18   a  and  18   b  to each other. In the pair of arm plate portions  18   a  and  18   b , the guide grooves  20  extended in the horizontal direction are provided at positions symmetric to each other. Into the respective guide grooves  20 , the pair of guide pins  11  and  11  of the one connector housing  1  are individually inserted. Each of the guide grooves  20  is composed of a circular arc portion  20   a  on one end side, and of a linear straight portion  20   b  communicating therewith. A diameter of the circular arc portion  20   a  is somewhat larger than a diameter of circular arc portions (long-width portions) of the guide pin  11 , and a width of the straight portion  20   b  is somewhat larger than a width of the cut portions (short-width portions) of the guide pin  11 . The guide grooves  20  are provided in such a way. Then, in the lever  2 , in rotation positions other than the rotation completion position shown in  FIG. 27 , the guide pins  11  are enabled to be arranged only in the circular arc portions  20   a , and a rotational movement thereof between the operation start position of  FIGS. 23 and 24  and the rotation completion position of  FIG. 27  is allowed. In the rotation completion position of  FIG. 27 , the guide pins  11  are allowed to slide from the circular arc portions  20   a  of the guide grooves  20  to the straight portions  20   b , and a linear sliding movement thereof between the rotation completion position of  FIG. 27  and the operation completion position of  FIG. 28  is allowed. As described above, the lever  2  is provided so as to rotationally move and linearly move with respect to the one connector housing  1 . 
   Moreover, in the pair of arm plate portions  18   a  and  18   b , cam grooves  21  are provided at positions symmetric to each other. Into the pair of cam grooves  21  and  21 , cam pins  36  of the other connector housing  3 , which are described later, are inserted when the one connector housing  1  is attached to the other connector housing  3 . The respective cam grooves  21  have one ends serving as opening portions open to end surfaces of the arm plate portions  18   a  and  18   b . Each of the cam grooves  21  is composed of a bent portion  21   b  varied in a direction where a distance r from the circular arc portion  20   a  of the guide groove  20  is made gradually closer as the bent portion  21   b  goes toward a deep recess thereof from the opening portion  21   a , and of a straight portion  21   c  arranged in parallel to the straight portion  20   b  of the guide groove  20 . 
   Furthermore, in the case where the lever  2  is vertically erected as shown in  FIG. 23 , an upper sidewall surface of the opening portion  21   a  is formed, as shown in  FIGS. 24 and 25 , as a sidewall stopper surface  17  of the cam groove  21 , on which the cam pin  36  is made to abut, when the one connector housing  1  is inserted into the other connector housing  3  without using the lever  2  and both thereof are set at a temporal connector-fitting position. Specifically, the cam pin  36  is inhibited from being inserted more at this stage, and only by the operation of the lever  2 , the cam pin will be inserted more. 
   Moreover, in each of the pair of arm plate portions  18   a  and  18   b , the first engaging hole (concave portion)  22  and the second engaging hole (concave portion)  23  are individually provided at positions symmetric to the others. Each of the engaging protrusions  12  of the one connector housing  1  is inserted into the first engaging hole  22  and the second engaging hole  23 . At the operation start position (rotation start position) where the lever  2  is erected vertically to the one connector housing  1 , the engaging protrusion  12  is inserted into the first engaging hole  22 , and thus a position of the lever  2  is maintained at the operation start position (rotation start position). Furthermore, at the operation completion position where the lever  2  is set parallel to the one connector housing  1 , the engaging protrusion  12  is inserted into the second engaging hole  23 , and thus the position of the lever  2  is maintained at the operation completion position. Note that, because the rotation completion position of the lever  2  is an operation midstream position, an engagement of the engaging protrusion  12  is not performed. 
   Furthermore, in inner walls of the pair of arm plate portions  18   a  and  18   b , the pair of lever-path adjusting guide pins  24  and  24  are individually provided. The pair of lever-path adjusting guide pins  24  and  24  are engaged with the pair of lever-path adjusting guide grooves  15  and  15  of the one connector housing  1 . 
   On a lower portion of the operating portion  19 , a pin holding portion  25  is provided, and in the pin holding portion  25 , a short pin  26  which is a fitting sensing terminal is held. The short pin  26  is composed of contact portions arranged in substantially parallel at an interval and a coupling short portion coupling the pair of contact portions to each other, and is formed of a conductive material which is formed into a substantially U-shape and rich in elasticity. Moreover, in the operation portion  19 , a finger insertion hole  27  is provided, and a size of the finger insertion hole  27  is set at an extent where only one finger of an operator can barely be inserted thereinto. 
   As shown in  FIGS. 20 ,  21 A and  21 B, the other connector housing  3  has a substantially rectangular shape in which an upper surface is opened, and an inner space thereof serves as an attachment space  30  of the one connector housing  1 . In a bottom surface portion  31  becoming a lower surface of the attachment space  30 , bolt insertion holes  32  shown in  FIG. 26  are formed. By bolts  33  inserted into the bolt insertion holes  32 , the other connector housing  3  is fixed to an unillustrated desired attachment surface. 
   Moreover, on the bottom surface portion  31  becoming the lower surface of the attachment space  30 , terminal hood/housing portions  34  are integrally provided in a state of being protruded in the vertical direction. In the terminal hood/housing portions  34 , a pair of power female terminals (terminals for power)  35  and  35  which are shown in  FIGS. 20 ,  21 A and  21 B are individually housed. When the one connector housing  1  is lowered from above and moved closer to the other connector housing  3 , the pair of power male terminals  9  and  9  of the one connector housing  1  enter the terminal hood/housing portions  34 , and are brought into contact with the pair of power female terminals  35  and  35 . Moreover, when the mutual power terminals  9  and  35  are in a contact state with each other and the one connector housing  1  is moved away from the other connector housing  3  and drawn upward, the pair of power male terminals  9  and  9  exit the terminal hood/housing portions  34 , and are brought into non-contact with the pair of power female terminals  35  and  35 . 
   Moreover, to the respective power female terminals  35 , one end sides of lead wires  39   a  are connected. One of the lead wires  39   a  and the other thereof are guided to a load unit  40  side of a power supply circuit D and a power supply unit  41  side of the power supply circuit D, respectively. Specifically, as shown in  FIG. 22 , a power switch SW 1  of the power supply circuit D is composed of the power male terminals  9  and the power female terminals  35  of both of the connector housings  1  and  3 . 
   Moreover, from the symmetric positions of an inner peripheral wall of the other connector housing  3 , the pair of cam pins  36  and  36  are protruded. The pair of cam pins  36  and  36  are inserted into the cam grooves  21  of the lever  2  when the one connector housing  1  is attached to the other connector housing  3 . Furthermore, on one side face portion of the other connector housing  3 , a pair of bus bars  37  and  37  are arranged in parallel at an interval. Each of the bus bars  37  and  37  is formed of a conductive material high in rigidity and into a flat rod shape. Upper end portions of the pair of bus bars  37  and  37  are exposed to the outside from the other connector housing  3 , and these exposed parts are formed as a pair of male terminals  38  and  38  which are fitting sensing terminals. Specifically, the pair of male terminals  38  and  38  are formed by utilizing the pair of bus bars  37  and  37 . Then, a fitting sensing switch SW 2  is composed of the pair of male terminals  38  and  38  and the short pin  26  of the lever  2 . The fitting sensing switch SW 2  is turned ON in a manner that the short pin  26  of the lever  2  is brought into contact with the pair of male terminals  38  and  38 , and turned OFF in a non-contact state of the short pin  26  of the lever  2 . To the pair of male terminals  38  and  38 , lead wires  39   b  are individually connected, and both of the lead wires  39   b  are guided to a relay circuit  42  in the power supply circuit D. 
   Next, the power supply circuit D is described. As shown in  FIG. 22 , the power supply circuit D includes the load unit  40 , and the power supply unit  41  which supplies electric power to the load unit  40 . To the load unit  40  and the power supply unit  41 , the power switch SW 1 , which is formed of the power terminals  9  and  35  of both of the connector housings  1  and  3 , and the relay circuit  42 , are connected in series. The relay circuit  42  is an electric circuit which is turned ON when the fitting sensing switch SW 2  is ON and turned OFF when the fitting sensing switch SW 2  is OFF. The power switch SW 1  formed of the power terminals  9  and  35  of both of the connector housings  1  and  3  is a mechanical switch as described above. 
   Next, an operation of the lever fitting-type power supply circuit breaker  1 A is described with reference to  FIGS. 23 to 30C .  FIG. 23  is a perspective view showing a state before the one connector housing is temporarily fitted to the other connector housing.  FIG. 24  is a perspective view showing a temporal connector-fitting position in a process of attaching the one connector housing to the other connector housing in a state where the lever is located at the operation start position.  FIG. 25  is a partially cutaway front view showing the same position in the same state as those of  FIG. 24 .  FIG. 26  is a cross-sectional view showing the same position in the same state as those of  FIG. 24 , in which the lever is omitted.  FIG. 27  is a perspective view showing the temporal connector-fitting position in the process of attaching the one connector housing to the other connector housing in a state where the lever is located at the rotation completion position.  FIG. 28  is a perspective view showing a state where the attachment of the one connector housing to the other connector housing is completed.  FIG. 29A  is a front view showing a state where the lever is located between the operation start position and the rotation completion position, explaining a moving process of cam pins when the one connector housing is attached to the other connector housing.  FIG. 29B  is a front view showing a state where the lever is located at the rotation completion position, explaining the moving process of the cam pins in a similar way to  FIG. 29A .  FIG. 29C  is a front view showing a state where the lever is located at the operation completion position, explaining the moving process of the cam pins in a similar way to  FIG. 29A .  FIG. 30A  is a front view showing a state where the lever is located between the operation start position and the rotation completion position, explaining a moving process of the lever-path adjusting guide pins when the one connector housing is attached to the other connector housing.  FIG. 30B  is a front view showing a state where the lever is located at the rotation completion position, explaining the moving process of the lever-path adjusting guide pins in a similar way to  FIG. 30A .  FIG. 30C  is a front view showing a state where the lever is located at the operation completion position, explaining the moving process of the lever-path adjusting guide pins in a similar way to  FIG. 30A . 
   First, an operation of bringing the power supply circuit D into a conductive state by the lever fitting-type power supply circuit breaker  1 A is described. As shown in  FIG. 23 , the lever  2  is set at the operation start position, and the one connector housing  1  is inserted into the attachment space  30  from above the other connector housing  3 . Then, the terminal hood portion  8  of the one connector housing  1  is inserted into the terminal hood/housing portion  34  of the other connector housing  3  while being fitted thereto. Moreover, the pair of cam pins  36  and  36  of the other connector housing  3  are inserted into the pair of cam grooves  21  and  21  of the lever  2 . Then, as shown in  FIGS. 24 and 25 , the pair of cam pins  36  and  36  enter the respective opening portions  21   a  of the pair of cam grooves  21  and  21 , and the pair of cam pins  36  and  36  are made to abut against the sidewall stopper surfaces  17  of the pair of cam grooves  21  and  21 . Thus, both of the connector housings  1  and  3  are set at the temporal connector-fitting position. At this temporal connector-fitting position, the respective power terminals  9  and  35  of both of the connector housings  1  and  3  are not brought into contact with each other yet. 
   Next, when the lever  2  is rotated in a direction of an arrow A 1  of  FIG. 24 , the lever  2  is rotated about the pair of guide pins  11  and  11  from the operation start position of  FIG. 24  to the rotation completion position of  FIG. 27 . Moreover, as shown in  FIG. 29A , the pair of cam pins  36  and  36  of the other connector housing  3  are moved in the pair of cam grooves  21  and  21  of the lever  2 . Thus, the one connector housing  1  gradually approaches and enters the inside of the other connector housing  3 . Then, the respective power terminals  9  and  35  of both of the connector housings  1  and  3  are brought into contact with each other before the lever  2  is located at the rotation completion position, and at the rotation completion position of the lever  2 , both of the connector housings  1  and  3  reach the connector-fitting position. 
   Next, when the lever  2  is slid in a direction of an arrow B 1  of  FIG. 27 , the pair of guide pins  11  and  11  are slid in the pair of guide grooves  20  and  20  of the lever  2 . In addition, as shown in  FIGS. 29B and 29C , the pair of cam pins  36  and  36  of the other connector housing  3  are slid in the pair of cam grooves  21  and  21  of the lever  2 , and thus the lever  2  is slid (linearly moved) from the rotation completion position of  FIG. 27  to the operation completion position of  FIG. 28 . The short pin  26  of the lever  2  is brought into contact with the pair of male terminals  38  and  38  of the other connector housing  3  before the lever  2  is located at the fitting completion position by the sliding movement. Then, when the fitting sensing switch SW 2  is turned ON, the relay circuit  42  is turned ON, and thus the power supply circuit D is brought into the conductive state for the first time. 
   In the above-described operation, in the process of rotationally moving the lever  2  from the operation start position to the rotation completion position, the respective terminals  9  and  35  of both of the connector housings  1  and  3  are brought into the contact state with each other, and the power switch SW 1  is turned ON, but the power supply circuit D is still non-conductive. In the process of sliding (linearly moving) the lever  2  from the rotation completion position to the operation completion position, the fitting sensing switch SW 2  is turned ON, and thus the relay circuit  42  is turned ON to bring the power supply circuit D into the conductive state for the first time. Therefore, the power supply circuit D can be prevented from being brought into the conductive state halfway through the operation of the lever  2 . 
   Next, an operation of bringing the power supply circuit D in the conductive state into a non-conductive state, that is, breaking the power supply by the lever fitting-type power supply circuit breaker  1 A is described. In the state of  FIG. 28 , when the lever  2  is slid in a direction of an arrow B 2  of  FIG. 28 , the pair of guide pins  11  and  11  are slid in the pair of guide grooves  20  and  20  of the lever  2 , and the pair of cam pins  36  and  36  of the other connector housing  3  are slid in the pair of cam grooves  21  and  21  of the lever  2 . Thus, the lever  2  is slid from the operation completion position of  FIG. 28  to the rotation completion position of  FIG. 27 . Before the lever  2  is located at the rotation completion position by this sliding movement, the short pin  26  of the lever  2  is separated from the pair of male terminals  38  and  38  of the other connector housing  3 , and is brought into the non-contact state therewith. Then, when the fitting sensing switch SW 2  is turned OFF, the relay circuit  42  is turned OFF, and at this point of time, the power supply circuit D has already been brought into the non-conductive state. 
   Next, when the lever  2  is rotated in a direction of an arrow A 2  of  FIG. 27 , the lever  2  is rotated about the pair of guide pins  11  and  11  from the rotation completion position of  FIG. 27  to the operation start position of  FIGS. 24 and 25 . Moreover, the pair of cam pins  36  and  36  of the other connector housing  3  are moved in the pair of cam grooves  21  and  21  of the lever  2 , and thus the one connector housing  1  is gradually moved upward so as to be separated from the other connector housing  3 , and is drawn therefrom. Then, before the lever  2  is located at the operation start position, the respective power terminals  9  and  35  of both of the connector housings  1  and  3  are brought into the non-contact state with each other, and at the operation start position of the lever  2 , both of the connector housings  1  and  3  are located at the temporal connector-fitting position. 
   In the above-described operation, in the process of linearly moving the lever  2  from the operation completion position to the rotation completion position, the fitting sensing switch SW 2  is turned OFF, and thus the relay circuit  42  is turned OFF to bring the power supply circuit D into the non-conductive state. In the process of rotationally moving the lever  2  from the rotation completion position to the operation start position, the power switch SW 1  between the respective power terminals  9  and  35  of both of the connector housings  1  and  3  is brought into a separated state. Thus, there is a time lag from the time when the power supply circuit D is turned OFF to the time when the power switch SW 1  between the respective power terminals  9  and  35  of both of the connector housings  1  and  3  is separated, and a discharge time is sufficiently ensured. Therefore, an arc discharge between the respective power terminals  9  and  35  of both of the connector housings  1  and  3  can be prevented. 
   Note that, when it is desired to separate the one connector housing  1  completely from the other connector housing  3 , the one connector housing  1  is taken out from above the other connector housing  3 . 
   As described above, in the lever fitting-type power supply circuit breaker  1 A, the fitting sensing switch SW 2  is composed of the pair of fitting sensing male terminals  38  and  38  and the short pin  26 , which can accordingly be installed in small installation spaces of the other connector housing  3  and the lever  2 , respectively. Hence, the other connector housing  3  and the lever  2  can be downsized, and eventually, the lever fitting-type power supply circuit breaker  1 A can be downsized. Moreover, a structure of the fitting sensing switch SW 2  is simple, and accordingly, the fitting sensing switch SW 2  can be manufactured at low cost. 
   In the above-described embodiment, the pair of male terminals  38  and  38  are formed by utilizing the pair of bus bars  37  and  37  arranged in the other connector housing  3 , the short pin  26  is formed into the substantially U-shape, and a structure is constructed such that the short pin  26  sandwiches the pair of male terminals  38  and  38  from both outsides thereof to contact the same male terminals  38  and  38 . Hence, the short pin  26  of the substantially U-shape can be brought into contact with the pair of bus bars  37  and  37  with large pressing force because the short pin  26  sandwiches the bus bars  37  and  37  to contact the same bus bars  37  and  37 . Accordingly, a highly reliable conductive state can be obtained. Moreover, a linear stroke in which the short pin  26  is brought into contact/non-contact with the pair of male terminals  38  and  38  can be shortened as compared with that of the conventional male/female terminal structure, and accordingly, a stroke of the linear operation of the lever  2  can be shortened. 
   In the above-described embodiment, the lever  2  includes the pair of arm plate portions  18   a  and  18   b  arranged at an interval, and the operating portion  19  coupling the pair of arm plate portions  18   a  and  18   b  to each other, and the short pin  26  is provided in the operating portion  19 . Accordingly, the short pin  26  can be installed without increasing the width of the lever  2 . 
   Moreover, in the above-described embodiment, the cam grooves  21  and the cam pins  36  are provided in the lever  2  and the other connector housing  3 , respectively. However, in a reverse order to this, the cam grooves  21  and the cam pins  36  may be provided in the other connector housing  3  and the lever  2 , respectively. Thus, a degree of freedom in design will be enhanced. Furthermore, though the guide grooves  20  and the guide pins  11  are provided in the lever  2  and the one connector housing  1 , respectively, the guide grooves  20  and the guide pins  11  may be provided in the one connector housing  1  and the lever  2 , respectively, in the reverse order to the above. Thus, the degree of freedom in design is enhanced. 
   Furthermore, in the above-described embodiment, the lever  2  is provided in the one connector housing  1  so as to be freely rotationally movable and freely linearly movable, and the lever  2  is moved from the operation start position to the operation completion position by the rotational movement and the linear movement (sliding movement). However, the present invention is also applicable to one which moves the lever  2  from the operation start position to the operation completion position only by the rotational movement or one which moves the lever  2  from the operation start position to the operation completion position only by the linear movement (sliding movement). A device, in which the lever  2  moves from the operation start position to the operation completion position only by the rotational movement, is formed such that the power switch is turned ON in a first half of the rotational movement process of the lever  2 , and that the fitting sensing switch SW 2  is turned ON in a second half of the rotational movement process.