Patent Publication Number: US-8986024-B2

Title: Power supply circuit disconnection device

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This is a Continuation of PCT Application No. PCT/JP2011/070839, filed on Sep. 13, 2011, and claims the priority of Japanese Patent Applications No. 2010-251101, filed on Nov. 9, 2010 and No. 2011-034397, filed on Feb. 21, 2011, the contents of these applications are incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present invention relates to a power supply circuit disconnection device that performs connection/disconnection of a power supply circuit by fitting/separation of connector housings, either of which is added with a lever. 
     BACKGROUND ART 
     On an electric vehicle or a hybrid vehicle, a power supply circuit disconnection device (service plug) capable of disconnecting electrification between a power supply unit and a load is mounted for the purpose of ensuring operation safety in maintenance of an electrical system thereof. As this type of conventional power supply circuit disconnection device, there is one disclosed in Japanese Patent Laid-Open Publication No. 2003-100382 (Patent Literature 1). 
     As shown in  FIG. 1  to  FIG. 3 , this power supply circuit disconnection device  100  includes: a first connector housing  101 ; a second connector housing  110  that is fitted to and separated from the first connector housing  101 ; and a lever  120  that is rotatably and slidably provided on the second connector housing  110 , and applies, by rotation thereof, fitting force and separation force between the second connector housing  110  and the first connector housing  101 . 
     On both side surfaces of the first connector housing  101 , a pair of cam pins  102  are protruded. In the first connector housing  101 , a one-side main terminal (not shown) and a one-side signal terminal (not shown) are individually provided. The one-side main terminal (not shown) is arranged in a connector fitting chamber. The one-side signal terminal (not shown) is arranged in an external hood portion  104 . 
     On both side surfaces of the second connector housing  110 , a pair of support shafts  111  are protruded. In the second connector housing  110 , an other-side main terminal (not shown) is provided. 
     On both side surfaces of the lever  120 , a pair of support shaft receiving grooves  121  are formed. Each of the support shaft receiving grooves  121  is composed of: a rotation support portion  121   a  that supports rotation of the support shaft  111 ; and a slide support portion  121   b  that communicates therewith, and supports sliding movement of the support shaft  111 . In such a way, the lever  120  is supported on the second connector housing  110  so as to be freely rotatable and slidable. On both side surfaces of the lever  120 , a pair of cam grooves  122  are provided. Each of the cam grooves  122  is composed of: a curve portion  122   a  that gradually changes a distance thereof from the rotation support portion  121   a ; and a straight portion  122   b  that communicates therewith, and is extended in parallel to the slide support portion  121   b . The cam pins  102  of the first connector housing  101  are inserted into the pair of cam grooves  122 . On a side portion of the lever  120 , a connector  104  in which an other-side signal terminal (not shown) is housed is arranged. The other-side signal terminal (not shown) is arranged in the hood portion  124 . 
     A main circuit switch (not shown) is composed of both of the main terminals (not shown). A signal circuit switch (not shown) is composed of both of the signal terminals (not shown). 
     In the above-described configuration, a description is made of a power supply conductive operation of the power supply circuit disconnection device  100 . As shown in  FIG. 1 , the second connector housing  110  in which the lever  120  is set at a first operation position is inserted into the connector fitting chamber (not shown) of the first connector housing  101 , and in addition, the cam pins  102  are inserted into inlets of the cam grooves  122  of the lever  120 . Both of the connector housings  101  and  110  turn to a temporarily fitted state of a connector. 
     The lever  120  is rotated from the first operation position to a second operation position. Then, the cam pins  102  move in the cam grooves  122 , the fitting force is applied between the second connector housing  110  and the first connector housing  101 , and the second connector housing  110  is gradually inserted into the connector fitting chamber of the first connector housing  101 . 
     As shown in  FIG. 2 , when the lever  120  is rotated to a fitting operation position of the connector, the first connector housing  101  and the second connector housing  110  turn to a completely fitted state. Both of the main terminals (not shown) gradually contact each other in the course to such a connector fitting operation position, and turn to a contact state at the connector fitting operation position. In such a way, the main circuit switch (not shown) turns to an ON state at the connector fitting operation position. 
     Next, the lever  120  is slidingly moved from the connector fitting operation position to the second operation position. In the course of this sliding movement, both of the signal terminals (not shown) gradually contact each other, and as shown in  FIG. 3 , turn to a contact state at the second operation position. In such a way, the signal circuit switch SW 2  is in the ON state at an operation completion position of the lever  120 . 
     Moreover, a power supply disconnection operation of the power supply circuit disconnection device  100  is performed by operating the lever  120  reversely to the above. That is to say, the lever  120  at the second operation position is slidingly moved to the connector fitting operation position, and is rotationally moved from the connector fitting operation position to the first operation position. 
     The power supply circuit disconnection device  100  does not turn a power supply circuit (not shown) to a conductive state until both of the main circuit switch (not shown) and the signal circuit switch SW 2  are switched on. That is to say, only in the case where the lever  120  is at the second operation position, the power supply circuit turns to the conductive state, and in the case where the lever  120  is at other operation positions, the power supply circuit is in a non-conductive state. 
     In such a way, a situation is prevented, which is caused by a mistake that an operator determines the power supply circuit to be in the non-conductive state since the lever  120  is not at the second operation position. 
     Moreover, with regard to the lever  120 , a slide operation thereof is performed from the second operation position to the connector fitting operation position, and a rotation operation thereof is performed from the connector fitting operation position to the first operation position. Therefore, there can be ensured a time lag in the operation of the lever  120  from the second operation position to the first operation position, that is, a time lag from when the signal circuit switch (not shown) is switched off to when the main circuit switch (not shown) is switched off. Accordingly, there does not occur a malfunction such as sparks resulting from an amount of electricity remaining after the signal circuit switch (not shown) is switched off. 
     CITATION LIST 
     Patent Literature 
     
         
         Patent Literature 1: Japanese Patent Laid-Open Publication No. 2003-100382 
       
    
     SUMMARY OF INVENTION 
     Technical Problem 
     However, in the above-described conventional power supply circuit disconnection device  100 , the lever  120  is not only rotated but also slidingly moved, and accordingly, an operation space is increased by the amount of a sliding range S. Moreover, there is a problem that a structure of the power supply circuit disconnection device  100 , which includes a metal die, becomes complicated. 
     In this connection, the present invention has been made in order to solve such problems as described above. It is an object of the present invention to provide a power supply circuit disconnection device that is capable of achieving reduction of the operation space and simplification of the structure including the metal die, and capable of preventing the malfunction resulting from the amount of electricity remaining after the signal circuit switch is switched off. 
     Solution to Problem 
     A first aspect of the present invention provides a power supply circuit disconnection device including: a first connector housing; a second connector housing fitted to and separated from the first connector housing; a lever that is rotatably provided on the second connector housing, applies fitting force and separation force between the second connector housing and the first connector housing by rotation thereof between a first operation position and a connector fitting operation position, and rotates from the connector fitting operation position to a second operation position; a main circuit switch that has main terminals provided individually on the first connector housing and the second connector housing, is turned to an OFF state at the first operation position of the lever, and is turned to an ON state at the connector fitting operation position and second operation position of the lever; a signal circuit switch that has signal terminals provided individually on the first connector housing and the lever, is turned to an OFF state at the first operation position and connector fitting operation position of the lever, and is turned to an ON state at the second operation position of the lever; a first lock portion that locks the lever at the second operation position; a second lock portion that locks the lever at the connector fitting operation position; and a lock release operation portion capable of releasing, by an operation thereof, a lock state of the second lock portion. 
     Preferably, the power supply circuit disconnection device further includes: a lock release inhibiting portion that inhibits movement of the second lock portion to a lock release position at the second operation position of the lever, and allows the movement of the second lock portion to the lock release position at the connector fitting position of the lever. 
     Preferably, the lever is configured to apply the fitting force and the separation force between the second connector housing and the first connector housing by the rotation thereof between the first operation position and the connector fitting operation position, and not to apply the fitting force and the separation force between the second connector housing and the first connector housing by rotation thereof between the connector fitting operation position and the second operation position. 
     Preferably, the first lock portion is capable of releasing lock thereof by rotation force applied to the lever by an operator, and the second lock portion is capable of releasing lock thereof by pressing force of the operator. 
     Preferably, both of the first lock portion and the second lock portion are capable of releasing lock thereof by pressing force of an operator. 
     Preferably, both of the first lock portion and the second lock portion are provided in the lock release operation portion, and lock release directions of the first lock portion and the second lock portion are directions different from each other. 
     Preferably, the first lock portion also serves as the lock release inhibiting portion. 
     Advantageous Effects of Invention 
     In accordance with the first aspect of the present invention, the lever moves from the first operation position through the connector fitting operation position to the second operation position by a rotation operation thereof. Accordingly, a required operation space is narrow by an amount that the lever is not slid, and in addition, a structure including a metal die can be simplified by an amount that a slide mechanism portion is not required. Moreover, the lever is rotated from the second operation position to the connector fitting operation position, and at the connector fitting operation position of the lever, the operation of the lock release operation portion is performed, whereby the second lock portion is displaced to the lock release position, and otherwise, the lever cannot be rotated to the first operation position. Accordingly, there can be ensured a time lag in the operation of the lever from the second operation position to the first operation position, that is, a time lag from when the signal circuit switch is switched off to when the main circuit switch is switched off. Therefore, there does not occur a malfunction such as sparks resulting from an amount of electricity remaining in the power supply circuit after the signal circuit switch is switched off. 
    
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         FIG. 1  shows a conventional example, and is a side view of a power supply circuit disconnection device in which a lever is located at a first operation position. 
         FIG. 2  shows the conventional example, and is a side view of the power supply circuit disconnection device in which the lever is located at a connector fitting operation position. 
         FIG. 3  shows the conventional example, and is a side view of the power supply circuit disconnection device in which the lever is located at a second operation position. 
         FIG. 4  shows a first embodiment of the present invention, and is a perspective view of a power supply circuit disconnection device in which a first connector housing and a second connector housing are in a separated state from each other. 
         FIG. 5  shows the first embodiment of the present invention, and is a perspective view of the power supply circuit disconnection device in which a lever is located at a first operation position, and the first connector housing and the second connector housing are in a temporarily fitted state to each other. 
         FIG. 6  shows the first embodiment of the present invention, and is a side view of the power supply circuit disconnection device in which the lever is located at the first operation position, and the first connector housing and the second connector housing are in the temporarily fitted state to each other. 
         FIG. 7  shows the first embodiment of the present invention, and is a side view of the power supply circuit disconnection device in which the lever is located at a connector fitting operation position, and the first connector housing and the second connector housing are in a completely fitted state to each other. 
         FIG. 8  shows the first embodiment of the present invention, and is a cross-sectional view of the power supply circuit disconnection device in which the lever is located at the connector fitting operation position, and the first connector housing and the second connector housing are in the completely fitted state to each other. 
         FIG. 9  shows the first embodiment of the present invention, and is a perspective view of the power supply circuit disconnection device in which the lever is located at a second operation position, and the first connector housing and the second connector housing are in the completely fitted state to each other. 
         FIG. 10  shows the first embodiment of the present invention, and is a side view of the power supply circuit disconnection device in which the lever is located at the second operation position, and the first connector housing and the second connector housing are in the completely fitted state to each other. 
         FIG. 11  shows the first embodiment of the present invention, and is a cross-sectional view of the power supply circuit disconnection device in which the lever is located at the second operation position, and the first connector housing and the second connector housing are in the completely fitted state to each other. 
         FIG. 12  shows a second embodiment of the present invention, and is a cross-sectional view of a power supply circuit disconnection device in which a lever is located at a connector fitting operation position, and a first connector housing and a second connector housing are in a completed fitted state to each other. 
         FIG. 13  shows the second embodiment of the present invention, and is a cross-sectional view of the power supply circuit disconnection device in which the lever is located at a second operation position, and the first connector housing and the second connector housing are in the completed fitted state to each other. 
         FIG. 14  shows a third embodiment of the present invention, and is a cross-sectional view of the power supply circuit disconnection device in which the lever is located at a connector fitting operation position, and a first connector housing and a second connector housing are in a completely fitted state to each other. 
         FIG. 15  shows the third embodiment of the present invention, and is a cross-sectional view of the power supply circuit disconnection device in which the lever is located at a second operation position, and the first connector housing and the second connector housing are in the completely fitted state to each other. 
         FIGS. 16(   a ) and  16 ( b ) show the third embodiment of the present invention:  FIG. 16  ( a ) is a side view of a lock structure; and a  FIG. 16(   b ) is a front view of the lock structure. 
     
    
    
     DESCRIPTION OF EMBODIMENTS 
     A description is made below of a first embodiment of the present invention based on the drawings. 
     (First Embodiment) 
       FIG. 4  to  FIG. 11  show the first embodiment of the present invention. As shown in  FIG. 4  to  FIG. 11 , a power supply circuit disconnection device  1 A includes: a first connector housing  10 ; a second connector housing  20  fitted to and separated from the first connector housing  10 ; and a lever  30  that is rotatably provided on the second connector housing  20 , and applies, by rotation thereof, fitting force and separation force between the second connector housing  20  and the first connector housing  10 . 
     On both side surfaces of the first connector housing  10 , a pair of cam pins  11  are protruded. The first connector housing  10  has a connector fitting chamber  10   a  in which an upper surface is opened. In the connector fitting chamber  10   a , two internal terminal hood portions  12  are provided. In the respective internal terminal hood portions  12 , one-side main terminals  13  are individually arranged. The respective main terminals  13  are female terminals. 
     In the first connector housing  10 , an external terminal hood portion  15  is provided on an outside of the connector fitting chamber  10   a . An upper portion of this external terminal hood portion  15  is opened. In the external terminal hood portion  15 , two signal terminals  16  as one-side terminals are arranged. A detailed configuration of these two signal terminals  16  is described later. 
     On both sidewalls of the external terminal hood portion  15 , first engaged portions  17  of a first lock portion LK 1  are protruded. The first lock portion LK 1  is composed of the first engaged portions  17  and first engaging portions  37  to be described later, and locks the lever  30  at a second operation position. The first engaged portions  17  are made easy to deflect and deform by slits  15   a  of the sidewalls of the external terminal hood portion  15 . 
     The second connector housing  20  includes: a housing body  21  in an inside of which a fuse  2  is housed; and a cover  22  attached onto an upper surface of this housing body  21 . The housing body  21  is formed to dimension/form at which the housing body  21  itself can be engaged with and separated from the connector fitting chamber  10   a  of the first connector housing  10 . In a lower portion of the housing body  21 , two other-side main terminals  23  are provided. The respective main terminals  23  are male terminals. The respective main terminals  23  protrude downward from the housing body  21 . The two main terminals  23  are connected to each other by the fuse  2 . A main circuit switch SW 1  is composed of the two main terminals on the first connector housing  10  side and the two main terminals  23  on the second connector housing  20  side. 
     On both side surfaces of the housing body  21 , a pair of rotation support shafts  24  are protruded. On both side surfaces of the housing body  21 , a pair of engaging protrusions  25  are provided. The respective engaging protrusions  25  are circular protrusions with a low height. 
     On the housing body  21 , a second engaging portion  26  of a second lock portion LK 2  is protruded. The second lock portion LK 2  is composed of the second engaging portion  26  and a second engaged portion  41  to be described later, and locks the lever  30  at a connector fitting operation position. The second engagement portion  26  is provided in a lock release operation portion  27 . The lock release operation portion  27  is deflectable and deformable by pressing force of an operator. On a rear side of the lock release operation portion  27  and the second engaging portion  26 , an elastic deformation space  28  for allowing elastic deformation thereof is formed. In such a way, when a lock release inhibiting portion  38  is not located at such a rear as a lock release position, the lock release operation portion  27  is operated to be pressed by the finger of the operator, and the like, whereby it is possible to move the second engaging portion  26  to the lock release position. 
     The lever  30  includes: a pair of arm plate portions  31 ; a coupling portion  32  that couples the pair of arm plate portions  31  to each other on a rotation tip end side; and an operation portion  33 . A pair of rotation receiving portions  34  are provided in the pair of arm plate portions  31 . On the pair of rotation receiving portions  34 , the pair of rotation support shafts  24  of the second connector housing  20  are pivotally supported. In such a way, the lever  30  is supported on the second connector housing  20  so as to be freely rotatable. In the pair of arm plate portions  31 , a pair of cam grooves  35  are formed. The cam pins  11  of the first connector housing  10  are inserted into the pair of cam grooves  35 . 
     As shown in  FIG. 7  and  FIG. 10 , each of the cam grooves  35  has: an entrance straight portion  35   a  that allows entrance of each of the cam pins  11 ; a curve portion  35   b  that communicates with this entrance straight portion  35   a  and gradually changes a distance thereof from a center of each of the rotation receiving portions  34 ; and a circular arc portion  35   c  that communicates with the curve portion  35   b  and has a constant distance thereof from the center of the rotation receiving portion  34 . 
     While the cam pins  11  are moving in the cam grooves  35 , the lever  30  rotates between a first operation position and the second operation position that is located via the connector fitting operation position. At the first operation position, the cam pin  11  is located at the entrance straight portion  35   a . At the connector fitting operation position, the cam pin  11  is located at a boundary position between the curve portion  35   b  and the circular arc portion  35   c . At the second operation position, the cam pin  11  is located at a deepest position of the circular arc portion  35   c.    
     That is to say, in a course where the lever  30  rotates between the first operation position and the connector fitting operation position, the cam pin  11  moves to the curve portion  35   b , the fitting force or the separation force is applied between the first connector housing  10  and the second connector housing  20 , and the first connector housing  10  and the second connector housing  20  move in a direction of being fitted to each other or a direction of being separated from each other. In a course where the lever  30  rotates between the connector fitting operation position and the second operation position, the cam pin  11  moves to the circular arc portion  35   c , the fitting force or the separation force is not applied between the first connector housing  10  and the second connector housing  20 , and the first connector housing  10  and the second connector housing  20  do not move in such a fitted direction or such a separated direction. 
     In each of the pair of arm plate portions  31 , at two spots thereof, position holding holes  36  are provided. In the lever  30 , the engaging protrusion  25  is engaged with either one of the position holding holes  36  at each of the first operation position and the second operation position. In such a way, the lever  30  is positioned at the first operation position and the second operation position by position holding force. 
     On the rotation tip end side of the pair of arm plate portions  31 , and at lower positions thereof, the pair of first engaging portions  37  of the first lock portion LK 1  are provided. The pair of first engaging portions  37  are formed to be capable of releasing the lock thereof by rotation force applied to the lever  30  by the operator. On the coupling portion  32 , the plate-like lock release inhibiting portion  38  is provided. 
     On a lower portion of the lever operation portion  33 , a hood portion  39  is provided. The hood portion  39  is opened downward. In the hood portion  39 , two signal terminals  40  as other-side terminals are arranged. A detailed configuration of the two signal terminals  40  is described later. Such a signal circuit switch SW 1  is composed of the two signal terminals  16  on the first connector housing  10  side and the two signal terminals  40  on the lever  30  side. 
     On the lever operation portion  33 , the second engaged portion  41  of the second lock portion LK 2  is provided. 
     Next, a description is briefly made of a power supply circuit system related to the power supply circuit disconnection device  1 A. Between a power supply unit (not shown) and a load unit (not shown), the main circuit switch SW 1  and a relay (not shown) switched on/off by the signal circuit switch SW 2  are connected in series. Hence, the power supply circuit turns to an ON state in such a manner that both of the main circuit switch SW 1  and the signal circuit switch SW 2  turn to an ON state. In other switch states, the power supply circuit is in an OFF state. 
     A description is made of a conductive operation of the power supply circuit by the power supply circuit disconnection device  1 A in the above-described configuration. As shown in  FIG. 4 , the second connector housing  20  in which the lever  30  is set at the first operation position is positioned to the connector fitting chamber  10   a  of the first connector housing  10 . Then, as shown in  FIG. 5  and  FIG. 6 , the second connector housing  20  is inserted into the connector fitting chamber  10   a  of the first connector housing  10 , and the cam pins  11  are inserted into the entrance straight portions  35   a  of the cam grooves  35  of the lever  30 . Both of the connector housings  10  and  20  turn to a temporarily fitted state of a connector. 
     Next, the lever  30  is rotated from the first operation position to the second operation position side. Then, the cam pins  11  move in the cam grooves  35 , the fitting force is applied between the second connector housing  20  and the first connector housing  10 , and the second connector housing  20  is gradually inserted into the connector fitting chamber  10   a  of the first connector housing  10 . 
     When the lever  30  is rotated to the connector fitting operation position, as shown in  FIG. 7  and  FIG. 8 , the second engaged portion  41  gets over the second engaging portion  26 , the second lock portion LK 2  turns to a lock position, and the first connector housing  10  and the second connector housing  20  turn to a completely fitted state to each other. In the course from the first operation position to the connector fitting operation position, both of the main terminals  13  and  23  start to contact each other, and such contact is completed at the connector fitting operation position. At the connector fitting operation position of the lever  30 , the main circuit switch SW 1  turns to the ON state. 
     When the lever  30  is rotated from the connector fitting operation position to the second operation position, as shown in  FIG. 9  to  FIG. 11 , the lock release inhibiting portion  38  enters the elastic deformation space  28 , and in addition, the first engaging portions  37  get over the first engaged portions  17 , and the first lock portion LK 1  turns to a lock position. In a course where the lever  30  rotates from the connector fitting operation position to the second operation position, both of the signal terminals  16  and  40  start to contact each other, and such contact is completed at the second operation position. At the second operation position of the lever  30 , the signal circuit switch SW 2  turns to the ON state. That is to say, the power supply circuit is non-conductive at the connector fitting operation position of the lever  30 , and does not turn to a conductive state until the lever  30  turns to the second operation position. 
     Next, a description is made of a power supply disconnection operation by the power supply circuit disconnection device  1 A. As shown in  FIG. 9  to  FIG. 11 , in a state where the lever  30  is located at the second operation position, the lever  30  is rotated by rotation force stronger than locking force between the first engaging portions  37  and the first engaged portions  17 . Then, the lock between the first engaging portions  37  and the first engaged portions  17  is released, and the rotation of the lever  30  is allowed. In such a way, as shown in  FIG. 7  and  FIG. 8 , the lever  30  is rotated to a completely fitting operation position of the connector. When the lever  30  is rotated to such a connector completely fitting operation position, the second engaged portion  41  of the lever  30  is engaged with the second engaging portion  26 , and the second lock portion LK 2  turns to the lock state. In such a way, the rotation of the lever  30  is inhibited once. In a course where the lever  30  rotates from the second operation position to the connector fitting operation position, both of the signal terminals  16  and  40  gradually come not to contact each other, and at the connector fitting operation position of the lever  30 , both of the signal terminals  16  and  40  come into non-contact with each other completely. Hence, at the connector completely fitting operation position of the lever  30 , the signal circuit switch SW 2  turns to the OFF state. The power supply circuit becomes non-conductive at the connector fitting operation position of the lever  30 . 
     Moreover, by the rotation of the lever  30  from the second operation position to the connector fitting operation position, the lock release inhibiting portion  38  of the lever  30  coms off from the elastic deformation space  28  of the first connector housing  10 . 
     Next, the lock release operation portion  27  is elastically deformed by using the elastic deformation space  28 , the second engaging portion  26  of the second lock portion LK 2  is displaced to the lock release position, and the lock thereof with the second engaged portion  41  is released. In such a way, rotation of the lever  30  to the first operation position side is allowed, and the lever  30  is rotated to the first operation position. In the rotation of the lever  30  from the connector fitting position to the first operation position, the separation force is applied between the second connector housing  20  and the first connector housing  10  by the cam grooves  35  and the cam pins  11 , and the second connector housing  20  is gradually pulled out from the connector chamber  10   a  of the first connector housing  10 . 
     As shown in  FIG. 5  and  FIG. 6 , at the first operation position of the lever  30 , the first connector housing  10  and the second connector housing  20  turn to the temporarily fitted state to each other. The main terminals  13  and  23  of both of the first connector housing  10  and the second connector housing  20  gradually come not to contact each other in the course from the connector fitting operation position to the first operation position, and turn to a non-contact state with each other completely at the first operation position. Hence, at the first operation position of the lever  30 , the main circuit switch SW 1  turns to the OFF state. 
     As described above, the power supply circuit disconnection device  1 A includes: the first connector housing  10 ; the second connector housing  20 ; the lever  30  rotatably provided on the second connector housing  20 ; the main circuit switch SW 1  that has the main terminals  13  and  23  provided in the first connector housing  10  and the second connector housing  20 , respectively, is turned to the OFF state at the first operation position of the lever  30 , and is turned to the ON state at the connector fitting operation position and second operation position of the lever  30 ; the signal circuit switch SW 2  that has the signal terminals  16  and  40  provided in the first connector housing  10  and the lever  30 , respectively, is turned to the OFF state at the first operation position and connector fitting operation position of the lever  30 , and is turned to the ON state at the second operation position of the lever  30 ; the first lock portion LK 1  that locks the lever  30  at the second operation position; the second lock portion LK 2  that locks the lever  30  at the connector fitting operation position; and the lock release operation portion  27  capable of releasing the lock state of the second lock portion LK 2  by the operation. 
     Hence, by the rotation operation, the lever  30  moves from the first operation position through the connector fitting operation position to the second operation position. Accordingly, the required operation space is narrow by an amount that the lever  30  is not slid, and in addition, the structure including the metal die can be simplified by an amount that a slide mechanism portion is not required. Moreover, the lever  30  is rotated from the second operation position to the connector fitting operation position, and at the connector fitting operation position of the lever  30 , the operation of the lock release operation portion  27  is performed, whereby the second lock portion LK 2  is displaced to the lock release position, and otherwise, the lever  30  cannot be rotated to the first operation position. Accordingly, there can be ensured a time lag in the operation of the lever  30  from the second operation position to the first operation position, that is, a time lag from when the signal circuit switch SW 2  is switched off to when the main circuit switch SW 1  is switched off. Therefore, there does not occur a malfunction such as sparks resulting from an amount of electricity remaining in the power supply circuit after the signal circuit switch SW 2  is switched off. 
     The power supply circuit disconnection device  1 A has the lock release inhibiting portion  38  that inhibits the movement of the second lock portion LK 2  to the lock release position at the second operation position of the lever  30 , and allows the movement of the second lock portion LK 2  to the lock release position at the connector fitting operation position of the lever  30 . Hence, the second engaging portion  26  cannot be moved to the lock release position until the lever  30  is rotated from the second operation position to the connector fitting operation position. Accordingly, at the connector fitting operation position of the lever  30 , an operation to move the second engaging portion  26  of the second lock portion LK 2  to the lock release position is inserted, and there can be surely ensured the time lag in the operation of the lever  30  from the second operation position to the first operation position, that is, the time lag from when the signal circuit switch SW 2  is switched off to when the main circuit switch SW 1  is switched off. Therefore, there can be surely avoided the occurrence of the malfunction such as the sparks resulting from the amount of electricity remaining in the power supply circuit after the signal circuit switch SW 2  is switched off. 
     The lever  30  is configured to apply the fitting force and the separation force between the second connector housing  20  and the first connector housing  10  by the rotation thereof between the first operation position and the connector fitting operation position, and not to apply the fitting force and the separation force between the second connector housing  20  and the first connector housing  10  by the rotation thereof between the connector fitting operation position and the second operation position. Hence, the cam grooves  35  are set so that, in the course where the lever  30  rotates from the second operation position to the connector fitting operation position, the pairs of main terminals  13  and  23  cannot move at all, and the signal switch SW 2  can be switched off. The pairs of main terminals  13  and  23  of the main circuit switch SW 1  move for the first time in the course where the lever  30  rotates from the connector fitting operation position to the first operation position after the power supply circuit turns to the OFF state. Hence, such a malfunction can be prevented, which results from that the main terminals  13  and  23  of the main circuit switch SW 1  move when both of the main circuit switch SW 1  and the signal circuit switch SW 2  are switched on, that is, the power supply circuit is conducting. 
     It is possible to release the lock of the first lock portion LK 1  by the rotation force applied to the lever  30  by the operator, and it is possible to release the lock of the second lock portion LK 2  by the pressing force of the operator. Hence, the operator can perform the operation from the first operation position of the lever  30  to the second operation position thereof without using a tool, a jig or the like. 
     (Second Embodiment) 
       FIG. 12  and  FIG. 13  show a second embodiment of the present invention. A power supply circuit disconnection device  1 B of this second embodiment is different from the power supply circuit disconnection device  1 A of the first embodiment only in configurations of the first lock portion LK 1  and the second lock portion LK 2 . 
     That is to say, as shown in  FIG. 12  and  FIG. 13 , both of a first engaged portion  17  of the first lock portion LK 1  and a second engaging portion  26  of the second lock portion LK 2  are provided in the lock release operation portion  27  of the second connector housing  20 . The lock release operation portion  27  is deflectable and deformable by the pressing force of the operator. On the rear side of the lock release operation portion  27  and the second engaging portion  26 , the elastic deformation space  28  for allowing elastic deformation thereof is formed. In such a way, when the lock release inhibiting portion  38  is not located at such a rear as the lock release position, the lock release operation portion  27  is operated to be pressed by the finger of the operator, and the like, whereby it is possible to move the second engaging portion  26  to the lock release position. 
     In addition, the first engaging portion  37  of the first lock portion LK 1  and the second engaged portion  41  of the second lock portion LK 2  enter engagement positions thereof from directions reverse to each other in the lock release operation portion  27 . Then, the first engaging portion  37  of the first lock portion LK 1  engages with the first engaged portion  17  at a position of entering the elastic deformation space  28 . That is to say, the first engaging portion  37  of the first lock portion LK 1  also serves as the lock release inhibiting portion of the first embodiment. At a second operation position (a position in  FIG. 13 ) of the lever  30 , the movement of the second engaging portion  26  of the second lock portion LK 2  to the lock release position is inhibited, and at a connector fitting operation position (a position in  FIG. 12 ) of the lever  30 , the movement of the second engaging portion  26  of the second lock portion LK 2  to the lock release position is allowed. 
     Other configurations are similar to those of the above-described first embodiment, and accordingly, a duplicate description is omitted. The same reference numerals are assigned to the same constituent spots between  FIG. 12  and  FIG. 13 , and clarification thereof is achieved. 
     Also in this second embodiment, similar effects to those of the above-described first embodiment are obtained. That is to say, there does not occur the malfunction such as the sparks resulting from the amount of electricity remaining in the power supply circuit after the signal circuit switch SW 2  is switched off. The malfunction can be prevented, which results from that the main terminals  13  and  23  of the main circuit switch SW 1  move when the power supply circuit is conducting. The operator can perform the operation from the first operation position of the lever  30  to the second operation position thereof without using the tool, the jig or the like. 
     The first lock portion LK 1  also serves as the lock release inhibiting portion, and accordingly, the simplification of the structure can be achieved. 
     (Third Embodiment) 
       FIG. 14  to  FIG. 16  show a third embodiment of the present invention. A power supply circuit disconnection device  1 C of this third embodiment is different from the power supply circuit disconnection device  1 A of the first embodiment only in configurations of the first lock portion LK 1  and the second lock portion LK 2 . 
     That is to say, as shown in  FIG. 14 ,  FIG. 15  and  FIG. 16 , in a similar way to the second embodiment, both of a first engaged portion  17  of the first lock portion LK 1  and a second engaging portion  26  of the second lock portion LK 2  are provided in the lock release operation portion  27  of the second connector housing  20 . The lock release operation portion  27  is deflectable and deformable by the pressing force of the operator individually in a direction R 1  in  FIG. 16  and a direction R 2  as a reverse direction thereto. On the rear side of the lock release operation portion  27  and the second engaging portion  26 , the elastic deformation space  28  for allowing elastic deformation of the lock release operation portion  27  and the second engaging portion  26  is formed. In such a way, when the lock release inhibiting portion  38  is not located at such a rear as the lock release position, the lock release operation portion  27  is operated to be pressed by the finger of the operator, and the like, whereby it is possible to move the second engaging portion  26  to the lock release position. 
     In addition, in a similar way to the above-described second embodiment, the first engaging portion  37  of the first lock portion LK 1  and the second engaged portion  41  of the second lock portion LK 2  enter engagement positions thereof from directions reverse to each other in the lock release operation portion  27 . Then, the first engaging portion  37  of the first lock portion LK 1  engages with the first engaged portion  17  at a position of entering the elastic deformation space  28 . That is to say, the first engaging portion  37  of the first lock portion LK 1  also serves as the lock release inhibiting portion of the first embodiment. At a second operation position (a position in  FIG. 15 ) of the lever  30 , the movement of the second engaging portion  26  of the second lock portion LK 2  to the lock release position is inhibited, and at a connector fitting operation position (a position in  FIG. 14 ) of the lever  30 , the movement of the second engaging portion  26  of the second lock portion LK 2  to the lock release position is allowed. 
     Moreover, unlike in the above-described first and second embodiments, the first engaging portion  37  and first engaged portion  17  of the first lock portion LK 1  are configured so that the lock therebetween cannot be released by the rotation force applied to the lever  30  by the operator, but that the lock can be released by deflecting the lock release operation portion  27  by the pressing force by the finger of the operator, and the like. That is to say, in the third embodiment, both of the first lock portion LK 1  and the second lock portion LK 2  are configured so as to be capable of releasing the lock thereof by the pressing force of the operator. 
     Furthermore, lock release directions of the first lock portion LK 1  and the second lock portion LK 2  are different directions. Specifically, the lock of the first lock portion LK 1  can be released by deflecting the lock release operation portion  27  in the arrow direction R 1 , and the lock of the second lock portion LK 2  can be released by deflecting the lock release operation portion  27  in the arrow direction R 2 . 
     Other configurations are similar to those of the above-described first embodiment, and accordingly, a duplicate description is omitted. The same reference numerals are assigned to the same constituent spots between  FIG. 14  and  FIG. 15 , and clarification thereof is achieved. 
     Also in this third embodiment, similar effects to those of the above-described first embodiment are obtained. That is to say, there does not occur the malfunction such as the sparks resulting from the amount of electricity remaining in the power supply circuit after the signal circuit switch SW 2  is switched off. The malfunction can be prevented, which results from that the main terminals  13  and  23  of the main circuit switch SW 1  move when the power supply circuit is conducting. The operator can perform the operation from the first operation position of the lever  30  to the second operation position thereof without using the tool, the jig or the like. 
     The first lock portion LK 1  also serves as the lock release inhibiting portion, and accordingly, the simplification of the structure can be achieved. 
     Both of the first lock portion LK 1  and the second lock portion LK 2  are configured so as to be capable of releasing the lock thereof by the pressing force of the operator. Hence, both of the lock release of the first lock portion LK 1  and the lock release of the second lock portion LK 2  can be performed only by definite lock release operations of the operator, and accordingly, safety is further enhanced. 
     Both of the first lock portion LK 1  and the second lock portion LK 2  are provided on the lock release operation portion  27 , and the lock release directions of the first lock portion LK 1  and the second lock portion LK 2  are different directions. Accordingly, both of the lock release of the first lock portion LK 1  and the lock release of the second lock portion LK 2  can be performed only by further definite lock release operations of the operator, and accordingly, the safety is further enhanced. 
     INDUSTRIAL APPLICABILITY 
     In accordance with the present invention, by the rotation operation, the lever moves from the first operation position through the connector fitting operation position to the second operation position. Accordingly, the required operation space is narrow by the amount that the lever is not slid, and in addition, the structure including the metal die can be simplified by the amount that the slide mechanism portion is not required. Moreover, the lever is rotated from the second operation position to the connector fitting operation position, and at the connector fitting operation position of the lever, the operation of the lock release operation portion is performed, whereby the second lock portion is displaced to the lock release position, and otherwise, the lever cannot be rotated to the first operation position. Accordingly, there can be ensured the time lag in the operation of the lever from the second operation position to the first operation position, that is, the time lag from when the signal circuit switch is switched off to when the main circuit switch is switched off. Therefore, there does not occur the malfunction such as the sparks resulting from the amount of remaining electricity after the signal circuit switch is switched off.