JP5231833B2 - Circuit breaker - Google Patents

Description

  The present invention relates to a circuit breaker.

2. Description of the Related Art Conventionally, there has been provided a circuit breaker in which a movable contact and a fixed contact are brought into and out of contact with each other through an opening / closing mechanism by an on / off operation of a handle (for example, see Patent Document 1). This circuit breaker moves in the front-rear direction (thickness direction) of the device body according to the rotation of the crossbar that rotates in response to the on / off operation of the handle protruding from the front side of the device body. And a movable contact fixed to the distal end of the movable contact and a fixed contact fixed to the container are brought into and out of contact with each other as the movable contact moves in the longitudinal direction of the container. It is like that.
Japanese Patent No. 3675467 (paragraph [0083] -paragraph [0088] and FIGS. 21-23)

  In the circuit breaker shown in Patent Document 1 described above, a leaf spring is used as a movable contact in order to absorb an impact between the movable contact and the fixed contact at the time of turning on. However, for example, a large current flows. When assumed, it is necessary to use a thick plate or the like as the movable contact.

  Here, when the movable contact and the fixed contact are brought into contact with or separated from each other, the movable contact of the conventional example relatively slides in the cut groove formed in the cross bar according to the rotation of the cross bar. However, for example, when a thick plate is used as the movable contact and a coil spring having elasticity that applies an urging force in the opening direction to the movable contact is used, the crossbar is changed according to the handle turning-off operation. There is a possibility that the cross bar cannot be rotated well because the movable contact cannot be smoothly slid over the inner surface of the cut groove when rotating.

  The present invention has been made in view of the above problems, and an object of the present invention is to provide a large-capacity circuit breaker capable of performing a smooth off operation.

According to the first aspect of the present invention, there is provided a container body provided with a load connection portion to which a load is connected and a power supply connection portion to which a power source is connected, and a fixed contact provided in an electric circuit between the load connection portion and the power connection portion. and into contact with the contact portion formed of a movable contact, a switching mechanism for contacting and separating the contact point portion, the contact portion through the opening and closing mechanism by operating the operation unit is exposed through the window holes formed in the front surface of the device body and a handle which separated, opening and closing mechanism comprises a movable contact made of a rigid body moving contact is fixed to the distal end portion has a holding groove variable kinematic contacts are inserted, on rotation in response to operation of the steering wheel In a circuit breaker equipped with a crossbar that contacts or separates the movable contact from the fixed contact by rotating between the position and the off-rotation position, the crossbar is attached in the direction to open the contact. The first spring and the movable contact And a second spring that urges the movable contact in a direction to open the contact portion, and the holding groove extends from the rotation fulcrum of the crossbar while the crossbar rotates from the on rotation position to the off rotation position. The end face on the near side is provided so as to be displaced from the on-state position in the direction opposite to the movable contact. When opening the contact portion, the crossbar is rotated by the biasing force of the first spring , and the first The movable contact is moved in the opening direction of the contact portion by the urging force of the two springs. When the crossbar is in the on-rotation position, the portion of the movable contact opposite to the movable contact is inserted into the holding groove. When the cross bar moves to the off-rotation position, the movable contact side portion of the movable contact is inserted into the holding groove .

  According to a second aspect of the present invention, the movable contact rotates about the rotation fulcrum according to the rotation of the cross bar, the cross bar is disposed between the fixed contact and the rotation fulcrum, and the second spring is crossed. It is characterized in that it is provided on the rotation fulcrum side with respect to the bar.

  According to the first aspect of the present invention, the cross bar and the movable contact are urged in the opening direction by the first and second springs, respectively, and the cross bar is rotated from the on-rotation position to the off-rotation position. Since the holding groove is formed so that the end surface of the crossbar near the rotation fulcrum is displaced in the opposite direction from the movable contact from the ON position, the crossbar is rotated from the ON rotation position to the OFF rotation position. When moving the contact, the movable contact does not rub the inner surface of the holding groove, and a smooth off operation can be performed, and the contact portion can be quickly opened, so that the generation of arc can be suppressed. This has the effect of extending the contact life. Furthermore, since the movable contact made of a rigid body is used and the cross-sectional area can be increased compared to the conventional case, the current capacity flowing through the movable contact can be increased, and as a result, an electric device having a large load current can be connected. There is an effect that can be done.

  According to the invention of claim 2, since the second spring is provided not on the fixed contact side but on the rotation fulcrum side, the distance between the second spring and the contact portion can be increased, and when the contact portion is opened. Even when an arc is generated, it is possible to prevent the second spring from being melted by the heat generated by the arc.

  An embodiment of the present invention will be described with reference to FIGS. The circuit breaker of this embodiment is attached to a distribution board such as a house, for example, and is used as a protective switch that supplies power to a connected load and shuts off the power supply in the event of an abnormality. In addition, although the circuit breaker of this embodiment is provided with the contact structure of 2 poles, only one pole is demonstrated about the same structure in the following description. Further, in the following description, unless otherwise specified, the direction of arrow ab in FIG. 4 is described as the vertical direction, the direction of arrow cd as the horizontal direction, and the direction of arrow ef as the front-back direction.

  As shown in FIGS. 1 to 4, the circuit breaker is changed in height in the left and right directions (in FIG. Two fixed contacts 2A, 2B arranged in parallel in a direction perpendicular to the paper surface, and movable contacts 3A, 3B facing each of the fixed contacts 2A, 2B so as to be able to contact and separate (that is, contact or separation) are fixed. Two movable contacts 4A, 4B and an opening / closing mechanism 5 for driving these two movable contacts 4A, 4B, and the movable contacts 3A, 3B can be handled via the opening / closing mechanism 5 by turning on / off the handle 6. The fixed contacts 2A and 2B are connected to and separated from each other. The fixed contacts 2A and 2B and the movable contacts 4A and 4B are arranged at different height positions in the vertical direction, and two in the vertical direction. Interposed between fixed contacts 2A and 2B The body 1 with one movable contact 4B and the fixed contact 2A to which the movable contact 3A of the other movable contact 4A contacts and separates from each fixed contact 2A and 2B. It is arrange | positioned in the height position which does not cross seeing from the width direction.

  A partition member 7 made of a synthetic resin molded product is disposed inside one end of the container body 1 in the front-rear direction (left side in FIG. 1) so as to be sandwiched between the two container pieces 1A and 1B. A terminal block 10B in which a lower fixed contact 2B is provided on one end side is accommodated in a space formed by the recess 9 provided in the side wall and the side wall (outer wall) of the body piece 1B. An upper fixed contact 2A is provided on one end side in a space formed by a recess (not shown) inside the side wall (outer wall) of the right side piece 1A and the vertical wall portion of the partition wall member 7. The terminal block 10A thus stored is stored.

  As shown in FIG. 1, the terminal block 10 </ b> B is formed from a terminal plate 11 bent in a substantially U shape with one side surface (surface on the side of the body piece 1 </ b> B) opened, and one end side of a lower piece 11 e of the terminal plate 11. An extension piece 11d that is integrally extended upward, a fixed contact 12B that is integrally extended from one end side of the lower piece 11e of the terminal plate 11 to the distal end side of the extension piece 11c that is integrally extended downward, and a fixed contact 12B The fixed contact 2B is caulked and fixed to the upper surface of one end, and a substantially M-shaped locking spring 13B that is placed on the lower piece 11e of the terminal plate 11 and accommodated in the terminal plate 11. In the terminal plate 11, the lower piece 11 e is placed on the horizontal wall portion 24 constituting the bottom portion of the concave portion 9 of the partition wall member 7, the extension piece 11 d is placed along the vertical wall 25 on one end side of the concave portion 9, and the vertical wall 25 One end of the terminal plate 11 is fitted into a notch formed between the lower end of the side wall portion 24 and one end portion of the lateral wall portion 24 so that the extension piece 11c is led out of the recess 9 and the partition member 7 is placed on the side of the body piece 1A. The top end of the fixed contact 12B, that is, the lower surface provided with the fixed contact 2B is placed on the ribs 26 and 26 provided on the bottom of the body piece 1A. At this time, the lower end portion of the fixed contact 2B protruding to the lower surface side of the fixed contact 12B is disposed in a recess formed between the ribs 26 and 26. Further, a protrusion 23 is integrally formed on the side surface of the side piece of the terminal plate 11 so as to be inserted into the holding piece 13b of the locking spring 13B to prevent the locking spring 13B from rattling.

  The locking spring 13B and the terminal plate 11 described above constitute a quick connection terminal as a conductor connecting portion, and an electric wire insertion formed obliquely downward on one end side in the front-rear direction (left side in FIG. 1) of the container 1 A core wire of an electric wire (not shown) inserted from the outside through the hole 16B is inserted between the upper piece 11b of the terminal plate 11 and the upper end of the locking piece 13a of the locking spring 13B and the upper end of the holding piece 13b. Then, the leading end of the locking piece 13a bites into the core wire to lock the core wire in the drawing direction of the electric wire, and the core wire is pressed against the upper piece 11b of the terminal plate 11 at the upper end surface of the pressing piece 13b. The core wire is electrically connected and mechanically held.

  Here, the release handle 17 is for releasing the above-described wire lock, and this release handle 17 has a rotating shaft (not shown) provided on one lower side surface (surface on the partition member 7 side) as a partition wall. A shaft portion (not shown) that is pivotally supported by a shaft hole (not shown) provided in the vertical wall portion of the member 7 and protrudes from the inner side surface of the body piece 1B is provided on the other lower side surface (not shown). 1 is pivotally supported in a recess 37 provided on the surface of the body piece 1B, and the operation portion 17a exposed to the outside of the body body 1 is manually operated to rotate counterclockwise in FIG. When moved, the drive protrusion 19 provided on the lower end side pushes the tip of one side end of the lock piece 13a of the lock spring 13B to bend the lock piece 13a and release the lock on the core wire. It can be done. The release handle 17 is always urged to rotate clockwise in FIG. 1 by a return spring (not shown). Further, two release handles 17 are provided side by side in the left-right direction (direction perpendicular to the paper surface of FIG. 1) with the partition member 7 interposed therebetween so as to correspond to each pole.

  On the other hand, the terminal block 10A is composed of a terminal plate 11, a locking spring (not shown), and a fixed contact 12A having a fixed contact 2A caulked and fixed to the tip side, like the terminal block 10B. The terminal block 11 of the terminal block 10A differs from the terminal plate 11 of the terminal block 10B in that an extension piece 11a is formed to extend upward from one end side of the lower piece 11e, and the extension piece 11a is extended from the upper end of the extension piece 11a. A stationary contact 12A is formed to extend at a right angle to it. The terminal block 10A is configured such that the lower piece 11e of the terminal plate 11 is placed on a bottom face (not shown) inclined downward of the concave portion of the body piece 1A, and a rising wall (not shown) on one end side of the concave portion. ) Along the upper end of the rising wall, the fixed contact 12A is led out of the recess, and the partition wall 14 is erected from the bottom of the body piece 1A. The terminal block 10A is disposed in the recess by disposing the tip end portion of the fixed contact 12A on the fixed contact arrangement portion 15 that is integrally formed by being inclined in the same manner as the bottom surface of the recess. At this time, the lower end portion of the fixed contact 2 </ b> A protruding to the lower surface side of the fixed contact 12 </ b> A is disposed in a recess 15 a formed on the upper surface of the fixed contact arrangement portion 15.

  The lock spring of the terminal block 10A and the terminal plate 11 constitute a quick connection terminal as a conductor connecting portion as in the case of the terminal block 10B, and an electric wire insertion hole (see FIG. When the electric wire is inserted from the outside via the not shown), the core wire is locked with the locking piece of the locking spring, and the core wire is pressed against the upper piece 11b of the terminal plate 11 with the holding piece, thereby electrically connecting the electric wire. It is connected and mechanically locked.

  And when releasing the electric wire locking described above, it is provided on the lower end side when the operation portion 17a (see FIG. 4) is manually operated and rotated counterclockwise in the same manner as the terminal block 10B. Further, the drive protrusion 19 pushes the tip of one side end of the locking piece of the locking spring to bend the locking piece and release the locking with respect to the core wire. Here, a load connecting portion is constituted by the terminal blocks 10A and 10B, and a contact portion is constituted by the fixed contact 2A and the movable contact 3A, and the fixed contact 2B and the movable contact 3B.

  Next, two conductive bars (not shown) disposed at different height positions in a distribution board (not shown) are provided in the other end in the front-rear direction (right side in FIG. 1) of the container body 1. Storage sections 90 and 90 for storing and arranging the connection terminals T1 and T2 to be plugged in, respectively, are provided in the vertical direction near the lower surface of the container 1. In addition, insertion portions 209a and 209b for inserting conductive bars formed by abutting substantially L-shaped cutout grooves formed between the end walls and the side walls of both container pieces 1A and 1B are provided in the respective storage portions. 90 and 90 are provided. The insertion portion 209a communicates with the upper storage portion 90, and the insertion portion 209b communicates with the lower storage portion 90.

  The connection terminals T1 and T2 are both substantially U-shaped, and are constituted by blade receiving springs that expand toward the tip after the tips of both side pieces parallel to the top and bottom are close to each other. In addition to facilitating the insertion of the bar, the conductive bar can be sandwiched at the central proximity. Here, the connection terminals T1 and T2, the storage portion 90, and the insertion portions 209a and 209b constitute a power supply connection portion.

  Here, the opening / closing mechanism 5 that opens and closes the movable contacts 4A, 4B is formed with an operating plate 43 that is a latch member, a cross bar 40, and a stepped locking portion 57 that locks one end of the operating plate 43. It comprises a tripping plate 41, a handle 6, a substantially U-shaped link 44, and the like.

  The handle 6 includes an operation portion 6a, a rotation portion 6b, and a handle shaft 6c, and a handle shaft 6c protruding from the center of both side surfaces of the rotation portion 6b is formed on the inner side surfaces of the body pieces 1A and 1B. Each of the body pieces 1A, 1B is held by being rotatably inserted into a shaft hole (not shown), and the operation section 6a is in a state in which both the body pieces 1A, 1B are in contact with each other. It faces the window hole 50 formed on the upper surface of the. Further, a torsion spring (not shown) is mounted on the handle shaft 6c, and the handle 6 is constantly urged in the off operation direction by the torsion spring. Further, a shaft hole 52 is provided at the lower end of the rotating portion 6b as shown in FIG. 1, and the upper shaft of the link 44 is rotatably inserted to be connected to the operation plate 43 via the link 44. .

  The actuating plate 43 is connected to the handle 6 via the link 44 by inserting the lower shaft of the link 44 through bearing holes provided in the center portions on both sides in the left-right direction (the direction perpendicular to the paper surface of FIG. 1). It is arranged in the container 1 so as to be movable up and down.

  The crossbar 40 is inserted between shaft parts 1A and 1B by inserting shaft parts 40a projecting on both side surfaces of the upper part into shaft holes (not shown) formed on the inner side surfaces of the body pieces 1A and 1B. As shown in FIG. 7, a kerf 54 into which the movable contact 4A is inserted from the side is formed on the side of the body piece 1A slightly below the shaft 40a as shown in FIG. 7, and the lower body piece 1B. A cut groove 55 into which the movable contact 4 </ b> B is inserted from the side is provided on each side portion. Then, on the end surface of the crossbar 40 on one end side in the front-rear direction (left side in FIG. 1), a locking member 130 (in FIG. 1, the container body) projecting from the partition wall member 7 and the two body pieces 1A and 1B, respectively. Only the locking piece 130 provided on the piece 1A is engaged) in a state where each movable contact 3A, 3B is separated from each fixed contact 2A, 2B (the state shown in FIG. 2 or FIG. 3). A recessed groove 131 to be contacted is formed along the width direction.

  Further, the lower end portion of the cross bar 40 is pushed by a coil spring 62A that is compressed and disposed between the lower end portion and the partition wall 63 erected from the bottom portion of the body piece 1A, and in the clockwise direction in FIG. The rotational force is energized. Here, in the cross bar 40, the on-rotation position (position shown in FIG. 1) where the movable contacts 3A, 3B and the fixed contacts 2A, 2B contact each other, and the movable contacts 3A, 3B and the fixed contacts 2A, 2B are separated. The pivot bar 55 is pivotally supported by the body 1 so as to be rotatable between the off-rotation position (the position shown in FIG. 2 or 3) and the kerf 55 is rotated from the on-rotation position to the off-rotation position. In the meantime, the end surface of the cross bar 40 closer to the rotation fulcrum (shaft portion 40a) is provided so as to be displaced in the opposite direction from the movable contact 4B from the ON position. Here, the first spring is constituted by the coil spring 62 </ b> A, and the holding groove is constituted by the cut groove 55.

  Here, the movable contact 4A is formed of a rigid conductive metal plate, and is inserted into the cut groove 54 of the crossbar 40 from the side, and a concave portion 54a (see FIG. 7) provided on the front side of the cut groove 54. It is biased upward by a coil spring for contact pressure (not shown) that is compressed between the bottom and the lower surface of the movable contact 4A, and the cross bar 40 rotates around the shaft 40a. When moved, the movable contact 4A rotates about the opening edge of the kerf 54 so that the movable contact 3A, which is caulked and fixed to the free end, is brought into contact with or separated from the fixed contact 2A.

  Similarly to the movable contact 4A, the movable contact 4B is formed of a rigid conductive metal plate, inserted from the side into the kerf 55 of the crossbar 40, and provided on the partition wall 63 of the body piece 1A. It is pivotally supported by the shaft groove 63a. Further, one end side of a coil spring 62B that is compressed between the bottom surface of the body piece 1A is fixed to the lower surface of the movable contact 4B. The coil spring 62B serves as a fulcrum in FIG. A clockwise rotational force is applied. Here, as shown in FIG. 2, the cross bar 40 is disposed between the fixed contact 2B and the shaft groove 63a, and the coil spring 62B is disposed on the shaft groove 63a side with respect to the cross bar 40. When the cross bar 40 is rotated in the clockwise direction, the movable contact 4B is rotated in the clockwise direction around the shaft groove 63a by the biasing force from the coil spring 62B, and the cross bar 40 is rotated counterclockwise. The movable contact 3B, which is caulked and fixed to the distal end side by rotating counterclockwise around the shaft groove 63a against the urging force from the coil spring 62B, becomes the fixed contact 2B. It is made to contact or separate. Here, the second spring is constituted by the coil spring 62B, and the rotation fulcrum is constituted by the shaft groove 63a.

  The tripping plate 41 is formed integrally with a shaft portion 41a, a protrusion portion 41b protruding above the shaft portion 41a, and a leg portion 41c protruding below the shaft portion 41a, and both ends of the shaft portion 41a in the left-right direction. By inserting the portion into a shaft hole (not shown) provided on the inner side surfaces of the two body pieces 1A and 1B, the two body pieces 1A and 1B are rotatably supported. Further, a locking portion 57 that engages and disengages one end (right end in FIG. 1) of the operation plate 43 is formed at the upper end portion of the protruding portion 41b, and is pushed and driven by the bimetal 46 at the distal end side of the leg portion 41c. The receiving portion 41d protrudes in the left-right direction. It should be noted that a torsion spring 81 is attached to the tripping plate 41 and is always urged counterclockwise by the torsion spring 81.

  Next, as shown in FIG. 1, the conductive plate 71B made of a thick plate metal material has a screw hole through which an adjustment screw 77 is screwed on one end side in the front-rear direction (right side in FIG. 1). A pair of caulking shafts project from the lower surface. An adjustment plate 72 made of a thin metal material in which a substantially L-shaped bimetal 46 constituting the thermal release device is welded and fixed to one end side is connected to the pair of caulks in a pair of holes penetrating the other end side. It is attached to the lower surface side of the conductive plate 71B by inserting and caulking the shaft. The adjustment screw 77 is used to change the distance between the adjustment plate 72 and the conductive plate 71B, and the lower end position of the bimetal 46, that is, the sensitivity of the thermal release device can be adjusted.

  At the welded portion of the bimetal 46 with the adjustment plate 72, the other end of the electric wire 79A having one end connected to the connection terminal T1 is welded, and the other end of the braided wire 79C is welded to the movable contact 4B at one end. The connection terminal T1, the electric wire 79A, the conductive plate 71B, the bimetal 46, the braided wire 79C, and the movable contact 4B are electrically connected. The other end of the electric wire 79E, one end of which is connected to the connection terminal T2 via the winding 68A and the electric wire 79B, is welded to the adjustment plate of the bimetal (not shown) provided on the other electrode side. The other end of the braided wire 79D welded to the movable contact 4A at one end is welded to a substantially central portion in the vertical direction of the bimetal, and the connection terminal T2, the wire 79B, the winding 68A, the wire 79E, the conductive plate ( (Not shown), bimetal, braided wire 79D, and movable contact 4A are electrically connected.

  Here, the conductive plate 71B and the bimetal 46 are held by the partition wall member 31 interposed between the body pieces 1A and 1B. The partition member 31 is made of a synthetic resin molded product having insulating properties, and is provided with a substantially rectangular recess 31c having an open side surface (surface on the side of the body piece 1B), and press-fitting the conductive plate 71B into the recess 31c. Thus, the conductive plate 71B and the bimetal 46 are accommodated in the container 1. In the present embodiment, a plurality (four in FIG. 1) of protrusions 31d are provided so as to face each other on the upper surface and the lower surface of the recess 31c, and the conductive plate 71B is press-fitted between these protrusions 31d. The plate 71B and the bimetal 46 are held. Furthermore, a notch 31e for allowing the adjustment screw 77 to face the outside is provided on the upper surface of the recess 31c. By adjusting the adjustment screw 77 through the notch 31e, the sensitivity of the thermal release device can be adjusted. It has become. After the adjustment, there is no need to adjust the adjustment screw 77. Therefore, the notch 31e is closed with a lid (not shown), the adjustment screw 77 is inadvertently operated, and foreign matters such as dust are contained in the body 1. To prevent intrusion. Further, between the container piece 1A and the partition member 31, another set of conductive plates and bimetals are held by the partition member 31 in the same manner as the conductive plates 71B and the bimetals 46 described above.

  Here, in the circuit breaker according to the present embodiment, an electromagnetic release unit that releases the switching mechanism 5 to open the contact portion when a short circuit current flows or a leakage current flows in the main circuit in a closed state. 47 is provided. As shown in FIGS. 1 and 6, the electromagnetic release unit 47 includes a substantially cylindrical coil bobbin 69 that is elongated in the front-rear direction (left-right direction in FIG. 6), a winding 68A wound around the coil bobbin 69, and a winding 68B, a zero-phase current transformer ZCT for detecting a leakage current flowing through the main circuit, and a secondary output generated in a secondary winding (not shown) of the zero-phase current transformer ZCT are input, And a circuit board 73 on which a leakage detection circuit for detecting leakage current based on the secondary output is formed.

  The coil bobbin 69 is formed of an insulating material such as a synthetic resin, and is provided with flanges 69C at both ends and an intermediate portion in the axial direction (left and right direction in FIG. 6), so that the winding drum portions 69A and 69B are provided between the flanges 69C. Are arranged side by side in the front-rear direction (left-right direction in FIG. 6). In the coil bobbin 69, a fixed iron core 57 made of magnetic metal is attached to the front side (right side in FIG. 6), and a movable iron core 58 made of magnetic metal is attached to the rear side so as to be movable in the axial direction. Is being dressed. Further, a release lever 58 </ b> A having a substantially L-shaped cross-sectional view that engages with the protrusion 41 b of the tripping plate 41 described above is attached to the tip (left end) of the movable iron core 58. Note that a return spring 70 is attached to one end of the release lever 58A (the right end in FIG. 6), and the release lever 58A and the movable iron core 58 are always urged rearward (to the left in FIG. 6). . That is, the position shown in FIG. 6 is the initial position (return position) of the release lever 58A and the movable iron core 58.

  Here, the winding 68A is wound around the winding body 69A of the coil bobbin 69. One end of the winding 68A is connected to the connection terminal T2 via the electric wire 79B, and the other end is connected to the electric wire 79E. Etc., and is connected to the movable contact 4B. On the other hand, the winding 68B is wound around the winding body 69B, and both ends of the winding 68B are connected to an output circuit (not shown) formed on the circuit board 73. That is, in the circuit breaker of the present embodiment, the winding 68A and the winding 68B are wound side by side in the axial direction of the coil bobbin 69, and the winding 68A and the winding 68B are in the same direction (in this embodiment, the rear side). (Clockwise direction when viewed from above).

  In the zero-phase current transformer ZCT, electric wires 79A and 79E forming electric paths of both voltage poles are inserted into a through hole provided in the center, and when a leakage current flows in the main circuit, the zero-phase current transformer ZCT An unbalanced current flows and a secondary output is generated in the secondary winding. This secondary output is input to the circuit board 73, and the input secondary output is compared with a predetermined threshold value by the leakage detection circuit, and if it is determined that a leakage current larger than the reference value flows, the output The winding 68B is energized by the circuit.

  Here, in the circuit breaker according to the present embodiment, the connection terminals T1 and T2, the storage portion 90, and the insertion portions 209a and 209b that constitute the power supply connection portion are arranged on the upper surface side that is generated near the lower surface of the device body 1. In the space, the circuit board 73 and the coil bobbin 69 constituting the electromagnetic release part 47 are arranged.

  Next, the assembly method of the circuit breaker of this embodiment is demonstrated. In the following description, it is assumed that the electric wires 79A, 79B, 79E and the braided wires 79C, 79D are fixed in advance at predetermined positions. First, the terminal block 10A is accommodated in the concave portion of the right body piece 1A, and the release handle 17 is assembled at a predetermined position together with the return spring. Furthermore, the handle 6 is assembled in place with a torsion spring. Thereafter, the movable contact 4A is fitted into the groove 54 of the cross bar 40 and the coil spring is housed in the recess 54a, and the cross bar 40 is rotatably disposed with the coil spring 62A at a predetermined position on the side of the body piece 1A. To do. Further, the operating plate 43 is connected to the handle 6 using a link 44 and arranged at a predetermined position.

  After that, the connection terminals T1 and T2 are respectively stored in the storage portions 90 and 90 provided on the other end side in the front-rear direction (right side in FIG. 1) of the container 1, and the rear side of the connection terminals T1 and T2 (in FIG. 1). The left-hand side) of the zero-phase current transformer ZCT is housed, and the coil bobbin 69 around which the circuit board 73 and the windings 68A and 68B are wound is housed in the space above the connection terminals T1 and T2 and the zero-phase current transformer ZCT. To do.

  Next, the movable contact 4B is fitted into the cut groove 55 of the cross bar 40, the vicinity of the bent portion of the movable contact 4B is pivotally supported by the shaft groove 63a provided in the partition wall 63, and one end side of the coil spring 62B is further supported. While being fixed to the movable contact 4B, the other end is fixed to the bottom of the container piece 1A.

  Thereafter, the partition wall member 31 is accommodated in the container body 1A, and the conductive plate 71B is press-fitted into the recess 31c of the partition wall member 31 so that the conductive plate 71B and the bimetal 46 are held by the partition wall member 31, and the trip plate 41 And a torsion spring 81 are rotatably arranged at a predetermined position.

  After the parts other than the partition member 7 and the terminal block 10B housed in the recess 9 of the partition member 7 and the release handle 17 and the return spring of the release handle 17 are assembled to the body piece 1A side, the terminal block 10B is assembled. The partition member 7 in which the release handle 17 and the release spring of the release handle are assembled in the recess 9 is disposed so as to overlap the body 1A side.

  Then, from this state, the body piece 1B is overlapped and joined to the body piece 1A side. At this time, claw-like hooking and locking portions 101 at the tips of the three elastic locking pieces 100 protruding from the container piece 1A side to the container piece 1B side are provided corresponding to the container piece 1B side. When each of the hooked portions (not shown) is locked, the body piece 1A and the body piece 1B are combined to assemble the body 1. On the contrary, when removing the body piece 1B from the body piece 1A, a driver (not shown) is inserted from each release hole 150 (see FIG. 4) of the body piece 1B opened corresponding to the hooked portion. Then, the hook piece 101 of each corresponding elastic lock piece 100 is pressed upward or downward to release the hook state with the hooked portion, thereby removing the piece 1B from the piece 1A. .

  Here, the initial position of the bimetal 46 is adjusted by moving the adjustment screw 77 arranged facing the notch 31e in the vertical direction using a tool, and after the adjustment, a lid is attached to close the notch 31e. To do.

  By the way, as shown in FIG.4 and FIG.5, the upper part by the side of the body piece 1B is provided with the protrusion part 105 in which the penetration hole 105a was penetrated, and the test for generating a pseudo short circuit state is provided. The button 78 exposes the tip portion upward from the insertion hole 105a. When the test button 78 is pressed, a short circuit is established, and a trip operation described later can be confirmed.

  Next, operation | movement of the circuit breaker of this embodiment is demonstrated based on FIGS. 1-3. FIG. 2 shows an off state. In this off state, the operation portion 6a of the handle 6 is in an inverted state exposed from the window hole 50, and the engagement state between the operation plate 43 and the tripping plate 41 is disengaged. is there. The cross bar 40 is urged to rotate in the clockwise direction in FIG. 2 by the coil spring 62A, and the movable contact 4A inserted through the cut groove 54 of the cross bar 40 is a free end (movable). The contact 3 </ b> A side) is moved upward, and the movable contact 4 </ b> B inserted through the kerf 55 is in a state where the free end (movable contact 3 </ b> B side) is moved upward by the biasing force from the coil spring 62 </ b> B. It is in. That is, each movable contact 3A, 3B is in a state of being separated from the corresponding fixed contact 2A, 2B.

  In this state, when the operation portion 6a of the handle 6 is rotated in the clockwise direction, the upper shaft of the link 44 is pushed downward, and the link 44 pushes down the operating plate 43 by the lower shaft. When the operating plate 43 is pushed down, one end (the right end in FIG. 1) of the operating plate 43 comes into contact with the locking portion 57 of the tripping plate 41, and the operating plate 43 rotates counterclockwise around the contact portion. And the other end (the left end in FIG. 1) abuts against the protrusion 84 provided at the upper end of the cross bar 40, and the cross bar 40 is counterclockwise against the biasing force from the coil spring 62A. Turn in the direction of.

  The movable contact 4B inserted into the cut groove 55 of the cross bar 40 by this rotation rotates counterclockwise against the urging force from the coil spring 62B and is provided on the free end side thereof. The movable contact 3B is brought into contact with the fixed contact 2B. Further, the movable contact 4A inserted into the cut groove 54 rotates counterclockwise in the same manner as the movable contact 4B, and the movable contact 3A provided on the free end thereof contacts the fixed contact 2A. Let

  When the handle 6 is further rotated in the clockwise direction, the upper shaft moves from the line connecting the position of the lower shaft of the link 44 and the rotation center of the handle 6 to the left as shown in FIG. In this state, the torsion spring of the handle 6, the coil spring 62A for urging the cross bar 44, and the spring force of the coil spring 62B for urging the movable contact 4B are balanced so that one end of the operating plate 43 and the trip plate 41 The latched state with the locking portion 57 is maintained, and the on state shown in FIG. 1 is maintained.

  Next, when the operation portion 6a of the handle 6 is turned counterclockwise in the on state, the position of the upper shaft of the link 44 is directed rightward along the line connecting the rotation center of the handle 6 and the lower shaft. Therefore, the latching state of the right end of the operating plate 43 and the engaging portion 57 of the tripping plate 41 is released, and the crossbar 40 is rotated in the clockwise direction by the biasing force of the coil spring 62A. At the same time, the handle 6 rapidly returns to the OFF side by the biasing force of the torsion spring. As the cross bar 40 rotates in the clockwise direction, the movable contact 4A rotates in the clockwise direction to move the free end upward, and the movable contact 3A is separated from the fixed contact 2A. The movable contact 4B is rotated clockwise around the shaft groove 63a by the urging force from the coil spring 62B to move the free end upward, and the movable contact 3B is separated from the fixed contact 2B. Let

  Here, if an excessive load current flows through the bimetal 46 in the ON state shown in FIG. 1, the bimetal 46 generates heat due to the overcurrent and is displaced in a curved manner. In this embodiment, the lower end of the bimetal 46 is displaced so as to move rearward (leftward in FIG. 1) and presses the receiving portion 41d of the tripping plate 41 in the leftward direction. Rotates in the clockwise direction around the shaft 41a.

  When the tripping plate 41 rotates in the clockwise direction, the latching state between the locking portion 57 of the tripping plate 41 and one end (right end) of the operation plate 43 is released, and the operation plate 43 is placed under the link 44. It rotates in the clockwise direction around the side axis. Therefore, the restriction of the cross bar 40 by the other end (left end) of the operating plate 43 is eliminated, and the cross bar 40 is rotated in the clockwise direction by the spring force of the coil spring 62A, and as shown in FIG. 3, the movable contact 4A 4B is returned to the OFF state, and the movable contacts 3A and 3B are separated from the fixed contacts 2A and 2B, respectively.

  Thereafter, the bimetal 46 returns to its original state due to the interruption of the electric circuit, and the tripping plate 41 returns to its original position by the urging of the torsion spring 81. Further, the handle 6 is rotated in the off direction (counterclockwise) by the bias of the torsion spring.

  In addition, when an excessive current such as a short circuit current flows through the winding 68A wound around the coil bobbin 69 in the on state shown in FIG. 1, a magnetic force is generated in the fixed core 57 constituting the electromagnetic release portion 47, and the movable core 58 Aspirate to the right. Then, the release lever 58A attached to the movable iron core 58 pulls the protruding portion 41b of the trip plate 41 forward (to the right in FIG. 6) against the biasing force of the return spring 70, and the trip plate 41 It rotates in the clockwise direction around the shaft 41a.

  When the trip plate 41 rotates in the clockwise direction as in the case where an excessive load current flows, the latched state between the locking portion 57 of the trip plate 41 and one end (right end) of the operation plate 43 is changed. When released, the operating plate 43 rotates in the clockwise direction around the lower axis of the link 44. Therefore, the restriction of the cross bar 40 by the other end (left end) of the operating plate 43 is eliminated, and the cross bar 40 is rotated in the clockwise direction by the spring force of the coil spring 62A, and the movable contacts 4A and 4B are turned off. The movable contacts 3A and 3B are separated from the fixed contacts 2A and 2B, respectively.

  Thereafter, when no magnetic force is generated in the fixed iron core 57 of the electromagnetic release part 47 due to the interruption of the electric circuit, the movable iron core 58 and the release lever 58A are returned to the original state by the spring force of the return spring 70, and the tripping plate 41 is moved to the torsion spring 81. Rotation and return to the original position by urging of. Further, the handle 6 is rotated in the off direction (counterclockwise) by the bias of the torsion spring.

  Further, when a leakage current flows in the main circuit in the ON state shown in FIG. 1, an unbalanced current flows in the zero-phase current transformer ZCT, and a secondary output is generated in the secondary winding. Thus, the winding 68B is energized by the output circuit. When the winding 68B is energized, a magnetic force is generated in the fixed iron core 57 that constitutes the electromagnetic release part 47, and the movable iron core 58 is attracted to the right. Then, the release lever 58A attached to the movable iron core 58 pulls the protruding portion 41b of the trip plate 41 forward (to the right in FIG. 6) against the biasing force of the return spring 70, and the trip plate 41 It rotates in the clockwise direction around the shaft 41a.

  When the tripping plate 41 rotates in the clockwise direction as in the case where the short-circuit current flows, the latched state between the locking portion 57 of the tripping plate 41 and one end (right end) of the operation plate 43 is released. The operation plate 43 rotates in the clockwise direction around the lower axis of the link 44. Therefore, the restriction of the cross bar 40 by the other end (left end) of the operating plate 43 is eliminated, and the cross bar 40 is rotated in the clockwise direction by the spring force of the coil spring 62A, and the movable contacts 4A and 4B are turned off. The movable contacts 3A and 3B are separated from the fixed contacts 2A and 2B, respectively.

  Thereafter, when no magnetic force is generated in the fixed iron core 57 of the electromagnetic release part 47 due to the interruption of the electric circuit, the movable iron core 58 and the release lever 58A are returned to the original state by the spring force of the return spring 70, and the tripping plate 41 is moved to the torsion spring 81. Rotation and return to the original position by urging of. Further, the handle 6 is rotated in the off direction (counterclockwise) by the bias of the torsion spring.

  In the circuit breaker of the present embodiment, the cross bar 40 is biased in the opening direction by the coil spring 62A, the movable contact 4B is biased in the opening direction by the coil spring 62B, and the cross bar 40 is turned on. While turning from the rotation position to the off-rotation position, the kerf 55 so that the end surface of the cross bar 40 near the rotation fulcrum (shaft portion 40a) is displaced from the on-state position in the opposite direction to the movable contact 4B. Since the (holding groove) is formed, when the cross bar 40 is rotated from the on-rotation position to the off-rotation position, the movable contact 4B does not hit the inner surface of the cut groove 55 and performs a smooth off operation. In addition, since the contact portion can be opened quickly, the generation of arc can be suppressed, and as a result, the contact life is prolonged. Further, since the movable contact 4B made of a rigid body is used and the cross-sectional area can be increased as compared with the conventional case, the current capacity flowing through the movable contact 4B can be increased, and as a result, an electric device having a large load current is connected. be able to.

  Further, since the coil spring 62B is provided not on the fixed contact 2B side but on the shaft groove 63a side which is a rotation fulcrum, the distance between the coil spring 62B and the contact portions (the fixed contact 2B and the movable contact 3B) is increased. Even when an arc is generated when the contact portion is opened, it is possible to prevent the coil spring 62B from being melted by the heat generated by the arc.

It is a side view of the state which showed the closed state of the circuit breaker of this embodiment, and removed the left-side body piece. It is a side view of the state which showed the open state same as the above, and removed the left-side body piece. It is a side view of the state which showed the trip state same as the above and which removed the left-side body piece. It is a perspective view same as the above. It is a right view same as the above. It is sectional drawing which fractures | ruptures partially seeing same as the above. (A) (b) is a perspective view of the crossbar used for the same as the above.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Body 1A, 1B Body piece 2A, 2B Fixed contact 3A, 3B Movable contact 4A, 4B Movable contact 5 Opening / closing mechanism 6 Handle 6a Operation part 40 Crossbar 50 Window hole 55 Groove (holding groove)
62A Coil spring (first spring)
62B Coil spring (second spring)

Claims (2)

A container provided with a load connection part to which a load is connected and a power supply connection part to which a power source is connected;
A contact portion composed of a fixed contact and a movable contact provided in an electric path between the load connection portion and the power supply connection portion;
An opening and closing mechanism for contacting and separating the contact portion,
A handle for moving the contact portion through the opening / closing mechanism by operating an operation portion exposed through a window hole formed in the front surface of the container body;
The opening and closing mechanism, the movable contactor comprising a rigid body the movable contact is fixed to the distal end portion has a holding groove in which the movable contactor is inserted, on the rotational position and the off-rotated according to the operation of the handle by pivoting between a position, in a circuit breaker comprising: a crossbar, a to the movable contact separated contact or open with the fixed contact,
A first spring for biasing the cross bar in a direction for opening the contact portion; and a second spring for biasing the movable contact in a direction for opening the contact portion by being attached to the movable contact. With
The holding groove has an end surface on the side close to the rotation fulcrum of the crossbar in the opposite direction to the movable contact while the crossbar rotates from the on rotation position to the off rotation position. Provided to displace,
When opening the contact portion, the cross bar is rotated by the biasing force of the first spring , and the movable contact is moved in the opening direction of the contact portion by the biasing force of the second spring. and then,
When the cross bar is in the on-rotation position, a portion of the movable contact opposite to the movable contact is inserted into the holding groove, and when the cross bar moves to the off-rotation position, the movable contact A circuit breaker characterized in that the movable contact side portion is inserted into the holding groove .   The movable contact rotates about a rotation fulcrum according to the rotation of the cross bar, the cross bar is disposed between the fixed contact and the rotation fulcrum, and the second spring is connected to the cross 2. The circuit breaker according to claim 1, wherein the circuit breaker is provided on the side of the rotation fulcrum with respect to the bar.

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