JP6832814B2 - Circuit breaker - Google Patents

Description

The present invention relates to a circuit breaker including an arc extinguishing device that extinguishes an arc generated between a fixed contact and a movable contact.

A circuit breaker that opens and closes an electric circuit by contacting and opening a fixed contact and a movable contact is known. In such a circuit breaker, when there is a pulling operation due to an overcurrent or an opening operation by the operation handle, the movable contact starts an opening operation in which the movable contact is separated from the fixed contact, and an arc is generated between the fixed contact and the movable contact.

The generated arc extends when the movable contact moves away from the fixed contact due to the opening operation. The extended arc moves to the arc extinguishing device by the magnetic action of the interrupted current, and is extinguished by being cooled by the arc extinguishing device. In this way, the arc generated between the contacts moves to the arc extinguishing chamber side by magnetic action after being stretched, but the arc moves to the opening / closing mechanism side due to the behavior of the movable contactor having the movable contact and the influence of the gas flow. It may move.

If the arc moves to the opening / closing mechanism side, the time required to cut off the current becomes long, or the current cannot be cut off, which may deteriorate the breaking performance. Further, even if the shutoff is normally performed, the movable contactor may be abnormally worn or a malfunction may occur due to damage to the mechanical parts.

Therefore, in Patent Document 1, an insulator directed to the bottom surface of the circuit breaker is attached to the movable contact, and arc gas directed to the opening / closing mechanism portion when the movable contact is opened is sent from the movable contact to the circuit breaker. A technique has been proposed to improve the arc extinguishing performance by blocking it with an insulator facing the bottom surface of the.

Japanese Unexamined Patent Publication No. 4-71134

However, in the circuit breaker described in Patent Document 1, since an insulator is arranged on the movable contacter toward the bottom surface of the circuit breaker, an insulator is provided between the movable contactor and the bottom surface of the circuit breaker. Space is required for placement, and the amount of movement of the movable contactor to the bottom surface of the circuit breaker is restricted. Therefore, the circuit breaker described in Patent Document 1 has problems that the distance between contacts after opening is small, the arc extinguishing performance is low, and the outer size of the circuit breaker is large.

The present invention has been made in view of the above, and an object of the present invention is to obtain a small circuit breaker having high arc extinguishing performance.

In order to solve the above-mentioned problems and achieve the object, the circuit breaker of the present invention moves a fixed contact having a fixed contact, a movable contact having a movable contact facing the fixed contact, and a movable contact. An opening / closing mechanism that makes contact and release between the fixed contact and the movable contact, an arc extinguishing device that extinguishes the arc generated between the fixed contact and the movable contact, and a position on the opening / closing mechanism side of the fixed contact. It is provided with an insulating wall portion that extends along the moving direction of the movable contact and regulates the movement of the arc toward the opening / closing mechanism portion. The movable contact is located on the opening / closing mechanism side of the insulating wall portion, and the base portion in which the acting force of the opening / closing mechanism portion acts in the extending direction of the insulating wall portion, the tip portion having the movable contact, and the base portion and the tip portion. It is provided with an intermediate portion in which an opening through which the insulating wall portion is inserted is formed. The midway portion faces the opening in a direction orthogonal to the direction from the base to the tip when viewed from the moving direction of the movable contact by the opening / closing mechanism, and is hung between the base and the tip, respectively. It has a pair of bridges.

According to the present invention, it is possible to obtain a circuit breaker that is compact and has high arc extinguishing performance.

Side sectional view of the circuit breaker according to the first embodiment Side sectional view of the circuit breaker according to the first embodiment Partial perspective view of the circuit breaker according to the first embodiment Partial top view of the circuit breaker according to the first embodiment External perspective view of the base portion shown in FIG. External perspective view of the movable contact shown in FIG. Top view of the movable contact shown in FIG. Side view of the movable contact shown in FIG. The figure which shows the state of the arc extinguishing at the time of a trip operation in the circuit breaker which concerns on Embodiment 1. Side sectional view of the circuit breaker according to the second embodiment Partial perspective view of the circuit breaker according to the second embodiment External perspective view of the insulating block according to the second embodiment External perspective view showing a state in which the insulating block according to the second embodiment is attached to the fixed contactor. The figure which shows the state of the arc extinguishing at the time of a trip operation in the circuit breaker which concerns on Embodiment 2. Side sectional view of the circuit breaker according to the third embodiment Partial perspective view of the circuit breaker according to the third embodiment Partial top view of the circuit breaker according to the third embodiment External perspective view of the movable contact according to the third embodiment Top view of the movable contact according to the third embodiment Side sectional view of the circuit breaker according to the fourth embodiment. Partial perspective view of the circuit breaker according to the fourth embodiment. Partial top view of the circuit breaker according to the fourth embodiment

The circuit breaker according to the embodiment of the present invention will be described in detail below with reference to the drawings. The present invention is not limited to this embodiment. In the following, for convenience of explanation, the coordinates of the XYZ axes are attached to the drawings. In the coordinates of the XYZ axes, the Z-axis positive direction is upward, the Z-axis negative direction is downward, the X-axis positive direction is right, the X-axis negative direction is left, and the Y-axis positive direction is forward. , Y-axis negative direction is the backward direction.

Embodiment 1.
1 and 2 are side sectional views of the circuit breaker according to the first embodiment of the present invention. The circuit breaker shown in FIG. 1 is in the on state, and the circuit breaker shown in FIG. 2 is in the off state. When the circuit breaker is off, the circuit breaker closes the electric circuit and current flows through the electric circuit. When the circuit breaker is off, the circuit breaker opens the circuit and cuts off the current in the circuit.

As shown in FIGS. 1 and 2, the circuit breaker 100 according to the first embodiment includes an insulating housing 1 including a base portion 1a and a cover portion 1b, an opening / closing mechanism portion 2 for opening / closing an electric current, and an overcurrent. It is provided with a trip device 3 that puts the circuit breaker 100 into a trip state when a current is generated. The base portion 1a and the cover portion 1b are formed of an insulating material such as a synthetic resin. The opening / closing mechanism 2 and the tripping device 3 are housed inside the insulating housing 1.

The opening / closing mechanism portion 2 is provided with an operation handle 21 that projects upward from the cover portion 1b and a crossbar 22 that moves in the vertical direction. By closing the operation handle 21, the circuit breaker 100 is turned on and the electric circuit is closed. Further, by opening the operation handle 21, the circuit breaker 100 is turned off and the electric circuit is opened. Since the configuration of the opening / closing mechanism portion 2 is known, a specific description thereof will be omitted.

When the tripping device 3 detects an overcurrent in the electric circuit, it acts on a trip bar (not shown) in the switching mechanism 2 to cause the switching mechanism 2 to perform a trip operation and put the circuit breaker 100 in a trip state. The trip device 3 may be configured as long as it can trip the circuit breaker 100 in the event of an overcurrent or a short-circuit accident, and a known configuration can be applied.

The circuit breaker 100 is a circuit breaker for wiring that detects an overcurrent or a short circuit accident and cuts off the electric circuit, but may be a circuit breaker or other circuit breaker that detects a leakage current and cuts off the electric circuit. .. When the circuit breaker 100 is an earth leakage breaker, the tripping device 3 acts on the opening / closing mechanism 2 to bring the circuit breaker 100 into a trip state when the leakage current is detected.

The circuit breaker 100 is movable further having a fixed contact 4 provided with a fixed contact 41 at one end and a power supply side conductor (not shown) connected to the other end, and a movable contact 51 facing the fixed contact 41. An arc extinguishing device 7 that extinguishes an arc generated between the contact 5 and the coil spring 6 that urges the movable contact 5 in a direction that separates the movable contact 51 from the fixed contact 41, and the fixed contact 41 and the movable contact 51. And a load-side terminal 8 connected to a load-side conductor (not shown).

The fixed contact 4, the movable contact 5, the coil spring 6, the arc extinguishing device 7, and the load side terminal 8 are arranged above the base portion 1a of the insulating housing 1. Further, the fixed contact 4, the movable contact 5, and the load side terminal 8 are formed by processing a metal plate. The arc extinguishing device 7 has a plurality of arc extinguishing plates 77 arranged in the vertical direction, and is housed inside the insulating housing 1.

As shown in FIG. 1, when the circuit breaker 100 is in the ON state, the crossbar 22 provided in the opening / closing mechanism 2 is moving downward, and the movable contactor resists the urging of the coil spring 6. 5 is pushed down. Therefore, the movable contact 51 of the movable contact 5 is in contact with the fixed contact 41 of the fixed contact 4. The movable contact 5 is connected to the load side terminal 8 via the tripping device 3. Therefore, the power supply side conductor (not shown) connected to the fixed contact 4 and the load side conductor (not shown) connected to the load side terminal 8 are electrically connected, and the fixed contact 4, the movable contact 5, and the movable contact 5 are electrically connected. A current flows through the electric line including the load side terminal 8.

Further, as shown in FIG. 2, when the circuit breaker 100 is in the off state, the crossbar 22 provided in the opening / closing mechanism portion 2 is moving upward, and the movable contact 5 is moved by the force of the coil spring 6. It is being pushed up. Therefore, the movable contact 51 of the movable contact 5 is separated from the fixed contact 41 of the fixed contact 4, and the electric path is cut off.

When the circuit breaker 100 is in the trip state, the movable contact 5 is pushed up by the force of the coil spring 6 to cut off the electric circuit, as in the case where the circuit breaker 100 is in the off state. In the state shown in FIG. 2, the movable contact 51 of the movable contact 5 is located at the position farthest from the fixed contact 41 of the fixed contact 4. Hereinafter, the position of the movable contact 5 shown in FIG. 2 may be described as the position where the movable contact 5 is maximally opened, and the state of the movable contact 5 shown in FIG. 2 may be described as the maximum open pole.

FIG. 3 is a partial perspective view of the circuit breaker according to the first embodiment, FIG. 4 is a partial top view of the circuit breaker according to the first embodiment, and FIG. 5 is a base portion shown in FIG. It is an external perspective view of. 6 is an external perspective view of the movable contact shown in FIG. 3, FIG. 7 is a top view of the movable contact shown in FIG. 3, and FIG. 8 is a side view of the movable contact shown in FIG. is there.

As shown in FIGS. 3 and 5, the insulating wall portions 11 and 12 are formed so as to project upward from the base portion 1a. As shown in FIGS. 1 and 2, the base portion 1a of the insulating housing 1 constitutes the bottom portion of the insulating housing 1. The insulating wall portions 11 and 12 are formed of an insulating material such as a synthetic resin, and are integrally formed with the base portion 1a. As shown in FIG. 4, the insulating wall portion 11 extends along the moving direction of the movable contact 5 at a position closer to the opening / closing mechanism portion 2 than the fixed contact 41 to restrict the movement of the arc to the opening / closing mechanism portion 2. To do. As a result, the arc extinguishing performance can be improved. The insulating wall portion 11 includes a lower wall portion 11a projecting upward from the base portion 1a and an upper wall portion 11b projecting upward from the center of the upper end of the lower wall portion 11a.

Although not shown, the circuit breaker 100 is provided with fixed contacts 4 for each pole. The insulating wall portion 12 is provided between the fixed contact 4 and the fixed contact 4 adjacent to each other in the left-right direction, and regulates the movement of the arc between the fixed contact 4 and the fixed contact 4. The circuit breaker 100 is a 3-pole circuit breaker, but the number of poles is not limited to 3 poles. Further, although the insulating wall portions 12 are arranged on the left and right sides of the fixed contactor 4, some of the insulating wall portions 12 are not shown for convenience of explanation.

Further, the insulating wall portion 11 is also provided for each pole, but the relationship between the insulating wall portion 11 in one pole and the fixed contact 4 and the movable contact 5 is fixed to the insulating wall portion 11 in the other pole. The same is true for the relationship between the contactor 4 and the movable contactor 5. In the following, the relationship between the insulating wall portion 11 and the fixed contact 4 and the movable contact 5 in one pole will be mainly described.

The insulating wall portion 11 is formed in a plate shape, and is arranged so that the extending direction of the movable contact 5 is the plate thickness direction. The insulating wall portion 11 is formed with a convex portion 13 extending in the vertical direction on the surface of the movable contact 5 on the movable contact 51 side.

As shown in FIGS. 3, 4, and 6, the movable contact 5 has a coil spring 6 attached, is located closer to the opening / closing mechanism portion 2 than the insulating wall portion 11, and has an acting force due to the crossbar 22. The opening 56, which is a space between the base 53 working in the extending direction of the insulating wall portion 11, the tip portion 54 having the movable contact 51, and the base portion 53 and the tip portion 54 through which the insulating wall portion 11 is inserted, is formed. It includes a formed midway portion 55. The movable contact 5 is formed by, for example, punching and bending a single metal plate.

As shown in FIGS. 6 to 8, the midway portion 55 of the movable contact 5 has a pair of bridge portions 57 and 58. The pair of bridge portions 57, 58 face each other with the opening 56 interposed therebetween when viewed from the vertical direction, which is the moving direction of the movable contact 5 by the opening / closing mechanism portion 2, and are respectively hung between the base portion 53 and the tip portion 54. Passed. Each of the bridge portions 57 and 58 is formed in a U shape, and is formed by bending upward from the base portion 53 and the tip portion 54 by bending.

The movable contact 5 is a member that forms an electric path, and an electric current flows along the extending direction of the movable contact 5. If there is a portion with a small cross-sectional area on the current path formed by the movable contact 5, the current required for energization may not flow. Since the opening 56 is formed in the middle portion 55 of the movable contact 5, the portion of the opening 56 cannot be used as a current path.

Therefore, the plate surface width L1 of the bridge portions 57 and 58 is made larger than the plate thickness L2. As a result, the cross-sectional area required for energization is secured. The value obtained by multiplying the total value of the plate surface widths L1 of the bridge portions 57 and 58 by the plate thickness L2 is the cross-sectional area of the intermediate portion 55. For example, by setting the total value of the plate surface widths L1 of the bridge portions 57 and 58 to be equal to or larger than the plate surface width L3 of the base portion 53, it is possible to secure the same cross-sectional area as the base portion 53 in the middle portion 55.

Further, as shown in FIG. 8, the bridge portions 57 and 58 are formed by bending so that the central portion projects upward in the side view. Therefore, as shown in FIG. 3, a recess 59 is formed in which the lower part of the bridge portions 57 and 58 is open, and the lower wall portion 11a of the insulating wall portion 11 is inserted into the recess 59. Therefore, the upper end portion of the lower wall portion 11a should be positioned upward as compared with the case where the bridge portions 57 and 58 are not formed by the bending process or when the bridge portions 57 and 58 are formed by the bending process so as to project downward. Can be done.

Further, as shown in FIG. 2, even when the movable contact 5 is in the maximum open position, the upper wall portion 11b of the insulating wall portion 11 is present inside the opening 56 and is movable. The state in which the upper wall portion 11b exists in the opening 56 is maintained over the entire movement range of the contactor 5. Therefore, the movable contact 5 does not ride on the upper end of the upper wall portion 11b. Therefore, it is possible to avoid a situation in which the movable contact 5 and the insulating wall portion 11 interfere with each other when the circuit breaker 100 is closed, and the circuit breaker 100 cannot be closed. It can be carried out.

Hereinafter, the operation of the circuit breaker 100 will be specifically described. FIG. 9 is a diagram showing a state of arc extinguishing during a trip operation in the circuit breaker according to the first embodiment. In FIG. 9, the arc 60 moved to the arc extinguishing device 7 is represented as an arc 60'. First, a case where the circuit breaker 100 is in the ON state when the power is normally supplied will be described.

When the circuit breaker 100 is in the ON state, the movable contact 51 and the fixed contact 41 are in contact with each other, as shown in FIGS. 1 and 3. In this state, the upper wall portion 11b of the insulating wall portion 11 is inserted through the opening 56 of the movable contact 5, but there is a vertical direction between the movable contact 5 and the base portion 1a and the lower wall portion 11a. There is a gap. Therefore, the contact between the movable contact 51 and the fixed contact 41 is not hindered by the base portion 1a.

Further, also in the left-right direction, which is the width direction of the circuit breaker 100, a gap is provided between the movable contact 5 and the insulating wall portions 11 and 12 as shown in FIG. Even if the movable contact 5 is tilted and comes into contact with the insulating wall portion 11, the contact with the insulating wall portion 11 is in a direction orthogonal to the moving direction of the movable contact 5, so that the movable contact 5 is substantially opened and closed. Does not affect operation.

When an overcurrent or a short-circuit accident occurs when the circuit breaker 100 is in the closed state, the movable contact 5 at the position of the broken line shown in FIG. 9 is instantly moved upward by the operation of the trip device 3 and is movable. The contactor 5 moves to the position of the solid line shown in FIG. In the process of moving the movable contact 5 from the position of the broken line to the position of the solid line, an arc 60 is generated between the fixed contact 41 and the movable contact 51 and extends.

In the process from the generation to the extension of the arc 60, the arc 60 has an opening / closing mechanism because the insulating wall portion 11 exists on the opposite side of the arc 60 from the arc 60, that is, between the arc 60 and the opening / closing mechanism portion 2. The movement toward the part 2 is suppressed.

Further, when the insulating wall portion 11 is exposed to the light and heat of the arc 60, the material constituting the insulating wall portion 11 is decomposed to generate an insulating gas, and the insulating gas is blown onto the arc 60. .. Therefore, the movement of the arc 60 to the arc extinguishing device 7 is accelerated, and the arc 60 quickly reaches the position of the arc 60'shown in FIG. Further, since the insulating gas exerts a large current limiting effect on the arc 60 itself, the moved arc 60'is easily attracted to the arc extinguishing plate 77, and is cooled and extinguished by the arc extinguishing plate 77. Be arced. In the following, the above-mentioned effect of the insulating gas of the insulating wall portion 11 may be described as a pressure effect.

In this way, in the insulating wall portion 11, the movement of the arc 60 toward the opening / closing mechanism portion 2 is suppressed by the insulating wall portion 11, and the arc current limiting effect due to the pressure is obtained, so that the damage to the opening / closing mechanism portion 2 is suppressed. At the same time, the arc extinguishing performance can be improved.

Further, the upper wall portion 11b of the insulating wall portion 11 exists inside the opening 56 even when the movable contact 5 is maximally opened. Therefore, in the arc 60 when the movable contact 5 is maximally opened, the insulating wall portion 11 is arc 60 in the entire range from the state where the movable contact 51 is in contact with the fixed contact 41 to the state where the movable contact 51 is maximally opened. It exists on the opposite side of the arc extinguishing device 7 when viewed from. Therefore, the pressure effect of the insulating wall portion 11 can be enhanced.

Further, as described above, the recesses 59 are formed in the bridge portions 57 and 58 in the upward direction, and the upper end portion of the lower wall portion 11a is upward as compared with the case where the upper end portion of the lower wall portion 11a is downward. Can be located in. Therefore, the pressure effect of the insulating wall portion 11 can be enhanced as compared with the case where the upper end portion of the lower wall portion 11a is located below.

The closer the insulating wall portion 11 is to the movable contact 51, the more the pressure effect of the insulating wall portion 11 can be enhanced. As shown in FIG. 9, the distance D1 between the insulating wall portion 11 and the movable contact 51 is smaller than the width W1 of the movable contact 51, less than half of the width W1 of the movable contact 51, and the insulating wall portion 11 Is placed near the movable contact 51. Therefore, the pressure effect of the insulating wall portion 11 can be enhanced. The distance D1 between the insulating wall portion 11 and the movable contact 51 is not limited to the above-mentioned example.

Further, as described above, a convex portion 13 is formed in the central portion of the insulating wall portion 11 in the width direction along the vertical direction. As a result, the distance between the insulating wall portion 11 and the movable contact 51 can be reduced at the central portion of the insulating wall portion 11 in the width direction. Therefore, the pressure effect of the insulating wall portion 11 can be enhanced as compared with the case where the convex portion 13 is not provided.

Further, the insulating wall portion 11 is covered with an insulating cover formed of a material having a higher arc extinguishing property than the insulating wall portion 11, or an insulating coating formed of a material having a higher arc extinguishing property than the insulating wall portion 11 is applied to the insulating wall portion. It can also be applied to part 11. As a result, the pressure effect of the insulating wall portion 11 can be further enhanced.

In the above-mentioned example, the movable contact 5 in contact with the crossbar 22 moves to open and close with the parallel movement of the crossbar 22 in the vertical direction. However, the moving direction of the crossbar 22 Is not limited to parallel movement in the vertical direction. For example, the movable contact 5 may be rotatably supported by the crossbar 22 and the electric circuit may be opened and closed by the rotational movement of the crossbar 22.

Further, in the above-described example, one contact pair, which is a pair of the fixed contact 4 and the movable contact 5, is provided for each pole, but two contact pairs may be provided for each pole. Also in this case, the arc extinguishing performance can be improved by forming the insulating wall portion 11 for each of the movable contacts 5.

As described above, the circuit breaker 100 according to the first embodiment includes a fixed contact 4 having a fixed contact 41, a movable contact 5 having a movable contact 51 facing the fixed contact 41, and a movable contact 5. An opening / closing mechanism 2 that moves to make contact and release between the fixed contact 41 and the movable contact 51, an arc extinguishing device 7 that extinguishes an arc 60 generated between the fixed contact 41 and the movable contact 51, and a fixed contact. It is provided with an insulating wall portion 11 that extends along the moving direction of the movable contact 5 at a position closer to the opening / closing mechanism portion 2 than 41 and regulates the movement of the arc 60 toward the opening / closing mechanism portion 2. The movable contact 5 is located closer to the opening / closing mechanism portion 2 than the insulating wall portion 11, and has a base portion 53 in which the acting force of the opening / closing mechanism portion 2 acts in the extending direction of the insulating wall portion 11 and a tip portion 54 having a movable contact 51. And an intermediate portion 55 in which an opening 56 is formed between the base portion 53 and the tip portion 54 and is a space through which the insulating wall portion 11 is inserted.

Therefore, in the circuit breaker 100, the movement of the arc 60 toward the opening / closing mechanism portion 2 is suppressed by the insulating wall portion 11 and the current limiting effect due to the pressure effect is obtained. Therefore, for example, damage to the opening / closing mechanism portion 2 is suppressed. At the same time, the arc extinguishing performance can be improved. Further, as compared with the configuration in which the movable contactor is provided with the insulator toward the base portion, the distance between the movable contactor 5 and the base portion 1a in the vertical direction can be reduced. Therefore, it is possible to suppress an increase in the external size of the circuit breaker 100, and it is possible to contribute to maintaining the external dimensions of the circuit breaker 100 or downsizing the circuit breaker 100. Further, it is possible to prevent the distance between the movable contact 5 and the movable contact 51 at the time of maximum opening from being reduced, and it is possible to prevent the arc extinguishing performance from being deteriorated. It is sufficient that the relationship that the opening 56 can be inserted through the insulating wall portion 11 is maintained, and the shape of the opening 56 is not limited to the above-mentioned example.

Further, the insulating wall portion 11 is formed to have a length existing inside the opening 56 over the entire moving range of the movable contact 5 by the opening / closing mechanism portion 2. As a result, the pressure effect of the insulating wall portion 11 can be further enhanced, and repeated opening and closing can be performed with high accuracy. The insulating wall portion 11 may be present inside the opening 56 within a part of the moving range of the movable contactor 5. Even in this case, the arc extinguishing performance can be improved as compared with the case where the insulating wall portion 11 is not provided.

Further, the intermediate portion 55 of the movable contact 5 is orthogonal to the direction from the base 53 to the tip 54 of the movable contact 5 when viewed along the vertical direction which is the moving direction of the movable contact 5 by the opening / closing mechanism portion 2. It has a pair of bridge portions 57 and 58 that face each other with the opening 56 in the direction and are laid between the base portion 53 and the tip portion 54, respectively.

As a result, it is possible to easily secure the cross-sectional area required for energization in the extending direction of the movable contact 5, and the two bridge portions 57 and 58 are hung between the base portion 53 and the tip portion 54. Since it is passed, the overall rigidity of the movable contact 5 can be increased.

Further, the bridge portions 57 and 58 are formed in a U shape, and the movable contact 51 is bent in a direction away from the fixed contact 41. As a result, it is possible to secure the cross-sectional area required for energization at the midway portion 55 while suppressing the length of the movable contact 5 in the left-right direction. Further, since the bridge portions 57 and 58 are kept away from the fixed contact 41, the attraction of the arc 60 can be suppressed and the damage to the movable contact 5 can be further reduced.

Further, the circuit breaker 100 includes an insulating housing 1 having a base portion 1a and a cover portion 1b, and accommodating the opening / closing mechanism portion 2 and the arc extinguishing device 7 in the space formed by the base portion 1a and the cover portion 1b. Be prepared. The insulating wall portion 11 is formed so as to project from the base portion 1a of the insulating housing 1. Since the insulating wall portion 11 is formed so as to project from the base portion 1a in this way, the number of parts of the circuit breaker 100 can be suppressed by forming the insulating wall portion 11 integrally with the base portion 1a. ..

Embodiment 2.
The circuit breaker according to the second embodiment is a circuit according to the first embodiment in that an insulating wall portion inserted into the opening 56 of the movable contact 5 is formed in an insulating block separate from the base portion. It is different from the circuit breaker 100. In the following, components having the same functions as those in the first embodiment will be designated by the same reference numerals and description thereof will be omitted, and the differences from the circuit breaker 100 according to the first embodiment will be mainly described.

10 is a side sectional view of the circuit breaker according to the second embodiment, FIG. 11 is a partial perspective view of the circuit breaker according to the second embodiment, and FIG. 12 is a partial perspective view of the circuit breaker according to the second embodiment. FIG. 13 is an external perspective view of the insulating block, which is an external perspective view showing a state in which the insulating block according to the second embodiment is attached to a fixed contactor.

As shown in FIG. 10, the circuit breaker 100A according to the second embodiment includes an insulating block 70 in place of the insulating wall portion 11 according to the first embodiment. The insulating block 70 is made of, for example, a synthetic resin and is made of a material having high arc extinguishing property.

As shown in FIGS. 11 and 12, the insulating block 70 includes a cover portion 71 that covers the periphery of the fixed contact 41 among the fixed contacts 4, and an insulating wall portion 72 that extends upward from the end portion of the cover portion 71. Be prepared.

The cover portion 71 is formed in an L shape in a side view, and has a shape that follows the bent shape of the fixed contactor 4. The cover portion 71 covers the periphery of the fixed contact 41, and the base portion 71a having one end continuous with the insulating wall portion 72, the protruding portions 71b and 71c covering the left and right of the protruding portion 42 of the fixed contact 4 and the base portion 71a. The other end is provided with a protruding portion 71d that continuously protrudes upward and covers the region of the fixed contact 4 facing the insulating wall portion 72.

The insulating wall portion 72 has the same shape as the insulating wall portion 11 according to the first embodiment. The insulating wall portion 72 includes a lower wall portion 72a that is continuous with the end portion of the cover portion 71 and projects upward, and an upper wall portion 72b that projects upward from the center of the upper end of the lower wall portion 72a. The lower wall portion 72a has the same shape as the lower wall portion 11a, and the upper wall portion 72b has the same shape as the upper wall portion 11b.

FIG. 14 is a diagram showing a state of arc extinguishing during a trip operation in the circuit breaker according to the second embodiment. When an overcurrent or a short-circuit accident occurs when the circuit breaker 100A is in the closed state, the movable contact 5 at the position of the broken line shown in FIG. 14 is instantly moved upward by the operation of the trip device 3 and is movable. The contactor 5 moves to the position of the solid line shown in FIG.

In the process of moving the movable contact 5 from the position of the broken line to the position of the solid line, an arc 60 is generated between the fixed contact 41 and the movable contact 51 and extends. In the process from the generation to the extension of the arc 60, since the insulating wall portion 72 exists on the side opposite to the arc extinguishing device 7 when viewed from the arc 60, the movement of the arc 60 toward the opening / closing mechanism portion 2 is suppressed. Further, similarly to the insulating wall portion 11, it is possible to obtain a current limiting effect due to the pressure effect of the insulating wall portion 72.

Further, since the insulating wall portion 72 is included in the insulating block 70 made of a material having high arc extinguishing property, the current limiting effect and the movement promoting effect of the arc 60 are further enhanced, and the arc extinguishing performance can be further improved. .. The insulating wall portion 72 is not formed integrally with the base portion 1a like the insulating wall portion 11 according to the first embodiment, and is configured as a part of the insulating block 70 that is separate from the base portion 1a. Therefore, by changing the material of the insulating block 70 without changing the material of the base portion 1a, it is possible to improve the arc extinguishing performance while suppressing the increase in cost.

As described above, the circuit breaker 100A according to the second embodiment has an insulating block 70 formed by integrally forming a cover portion 71 and an insulating wall portion 72 that cover the periphery of the fixed contact 41 among the fixed contacts 4. Be prepared. Since the insulating block 70 and the base portion 1a are separate bodies, by changing the material of the insulating block 70 without changing the material of the base portion 1a, the arc extinguishing performance is improved while suppressing the increase in cost. Can be planned. The insulating block 70 may be formed of the same material as the base portion 1a.

Embodiment 3.
The circuit breaker according to the third embodiment is the circuit breaker 100 according to the first embodiment in which the movable contact 5 has two bridge portions 57 and 58 in that the movable contact has one bridge portion. different. In the following, components having the same functions as those in the first embodiment are designated by the same reference numerals and the description thereof will be omitted, and the differences from the circuit breaker 100 according to the first embodiment will be mainly described.

15 is a side sectional view of the circuit breaker according to the third embodiment, FIG. 16 is a partial perspective view of the circuit breaker according to the third embodiment, and FIG. 17 is a partial perspective view of the circuit breaker according to the third embodiment. It is a partial top view of a circuit breaker. FIG. 18 is an external perspective view of the movable contact according to the third embodiment, and FIG. 19 is a top view of the movable contact according to the third embodiment.

As shown in FIG. 15, the circuit breaker 100B according to the third embodiment includes an insulating wall portion 81 instead of the insulating wall portion 11. Further, the circuit breaker 100B includes a movable contact 5B instead of the movable contact 5.

As shown in FIGS. 16 and 17, the insulating wall portion 81 is formed of an insulating material such as a synthetic resin like the insulating wall portion 11, and is formed so as to project upward from the base portion 1a. The insulating wall portion 81 includes a lower wall portion 81a projecting upward from the base portion 1a and an upper wall portion 81b projecting upward from the center of the upper end of the lower wall portion 81a. The upper wall portion 81b is formed with a convex portion 83 extending in the vertical direction on the surface of the movable contact 5B on the movable contact 51 side.

In the insulating wall portion 81, the insulation according to the first embodiment, wherein one side portion of the upper wall portion 81b is continuous with the insulating wall portion 12, and one side portion of the upper wall portion 11b is not continuous with the insulating wall portion 12. It is different from the wall part 11.

As shown in FIGS. 16 to 19, the movable contact 5B is located between the base 53 on which the acting force of the opening / closing mechanism 2 acts, the tip 54 having the movable contact 51, and the base 53 and the tip 54. It is provided with an intermediate portion 55B in which an opening 56B, which is a space through which the insulating wall portion 81 is inserted, is formed. The opening 56B is formed in a slit shape as shown in FIG. 19, and the left side is open. Like the movable contact 5, the movable contact 5B is formed by, for example, punching and bending a single metal plate.

The midway portion 55B faces the opening 56B when viewed from the vertical direction, which is the moving direction of the movable contact 5B by the opening / closing mechanism portion 2, and one bridge portion 57B is hung between the base portion 53 and the tip portion 54. Has. Like the bridge portion 57, the bridge portion 57B is formed in a U shape, and is formed by bending upward from the base portion 53 and the tip portion 54 by bending.

The plate surface width L4 of the bridge portion 57B is made larger than the plate thickness L5 of the movable contact 5B, thereby ensuring the cross-sectional area required for energization. The value obtained by multiplying the plate surface width L4 of the bridge portion 57B by the plate thickness L5 is the cross-sectional area of the intermediate portion 55B. For example, by setting the total value of the plate surface width L4 of the bridge portion 57B to be equal to or larger than the plate surface width L6 of the base portion 53, it is possible to secure the same cross-sectional area as the base portion 53 in the middle portion 55B.

Further, the bridge portion 57B is formed by bending so that the central portion protrudes upward in the side view, like the bridge portion 57, and as shown in FIGS. 18 and 19, a recess having an open lower side. 59B is formed on the bridge portion 57B. Therefore, the upper end portion of the insulating wall portion 81 can be positioned upward as compared with the case where the bridge portion 57B is not formed by the bending process or when the bridge portion 57B is formed by the bending process so as to project downward.

As described above, the circuit breaker 100B according to the third embodiment includes the movable contact 5B, and the intermediate portion 55B of the movable contact 5B is the moving direction of the movable contact 5B by the opening / closing mechanism portion 2. It has a bridge portion 57B that faces the opening 56B in the left-right direction that is orthogonal to the direction from the base portion 53 to the tip portion 54 when viewed from the vertical direction, and is bridged between the base portion 53 and the tip portion 54. The opening 56B is formed in a slit shape, and the side opposite to the bridge portion 57B side is open in the left-right direction.

Therefore, as described above, one side portion of the upper wall portion 81b of the insulating wall portion 81 can be extended to the insulating wall portion 12. Therefore, the movement of the arc 60 toward the opening / closing mechanism portion 2 is further suppressed by the insulating wall portion 81, and the current limiting effect of the arc 60 due to the pressure effect can be obtained. Therefore, while suppressing damage to the opening / closing mechanism portion 2, while suppressing damage to the opening / closing mechanism portion 2. The arc extinguishing performance can be improved.

Embodiment 4.
The circuit breaker according to the fourth embodiment has an insulating block having an insulating wall portion having the same shape as the insulating wall portion 81 in place of the insulating wall portion 81 according to the third embodiment. It is different from the circuit breaker 100B. In the following, components having the same functions as those in the third embodiment are designated by the same reference numerals and the description thereof will be omitted, and the differences from the circuit breaker 100B according to the third embodiment will be mainly described.

20 is a side sectional view of the circuit breaker according to the fourth embodiment, FIG. 21 is a partial perspective view of the circuit breaker according to the fourth embodiment, and FIG. 22 is a partial perspective view of the circuit breaker according to the fourth embodiment. It is a partial top view of a circuit breaker.

As shown in FIG. 20, the circuit breaker 100C according to the fourth embodiment includes an insulating block 90 instead of the insulating wall portion 11. Like the insulating block 70, the insulating block 90 is made of, for example, a synthetic resin and is made of a material having high arc extinguishing property.

As shown in FIGS. 21 and 22, the insulating block 90 includes a cover portion 91 that covers the periphery of the fixed contact 41 among the fixed contacts 4, and an insulating wall portion 92 that extends upward from the end portion of the cover portion 91. Be prepared. The cover portion 91 has the same shape as the cover portion 71. The insulating wall portion 92 has the same shape as the insulating wall portion 81, and includes a lower wall portion 92a protruding upward from the end portion of the cover portion 91 and an upper wall portion 92b protruding upward from the center of the upper end of the lower wall portion 92a. including. A convex portion 93 is formed on the upper wall portion 92b. One side of the upper wall portion 92b of the insulating wall portion 92 is continuous with the insulating wall portion 12.

The opening 56B of the movable contact 5B is formed in a slit shape as shown in FIGS. 21 and 22, and the negative direction side of the X axis is open. As described above, one side of the insulating wall portion 92 is an insulating wall portion. It has been extended to 12. Therefore, the movement of the arc 60 toward the opening / closing mechanism portion 2 is further suppressed by the insulating wall portion 92, and the current limiting effect of the arc 60 due to the pressure effect can be obtained. Therefore, while suppressing damage to the opening / closing mechanism portion 2, while suppressing damage to the opening / closing mechanism portion 2. The arc extinguishing performance can be improved.

The configuration shown in the above-described embodiment shows an example of the content of the present invention, can be combined with another known technique, and is one of the configurations without departing from the gist of the present invention. It is also possible to omit or change the part.

1 Insulated housing, 1a base, 1b, 71, 91 cover, 2 opening / closing mechanism, 3 tripping device, 4 fixed contact, 5, 5B movable contact, 6 coil spring, 7 arc extinguishing device, 8 load Side terminal, 11,12,72,81,92 Insulated wall part, 11a, 72a, 81a, 92a Lower wall part, 11b, 72b, 81b, 92b Upper wall part, 13,83,93 Convex part, 21 Operation handle, 22 Crossbar, 41 Fixed contact, 42, 71b, 71c, 71d protruding part, 51 movable contact, 53 base, 54 tip, 55, 55B midway, 56, 56B opening, 57, 57B, 58 bridge, 59 , 59B recess, 60, 60'arc, 70, 90 insulation block, 77 arc extinguishing plate, 100, 100A, 100B, 100C circuit breaker.

Claims (6)

With fixed contacts with fixed contacts,
A movable contact having a movable contact facing the fixed contact,
An opening / closing mechanism that moves the movable contact to make contact and release between the fixed contact and the movable contact.
An arc extinguishing device that extinguishes the arc generated between the fixed contact and the movable contact,
An insulating wall portion that extends along the moving direction of the movable contact at a position closer to the opening / closing mechanism portion than the fixed contact and regulates the movement of the arc toward the opening / closing mechanism portion is provided.
The movable contact is
A base portion located closer to the opening / closing mechanism portion than the insulating wall portion and in which the acting force of the opening / closing mechanism portion acts in the extending direction of the insulating wall portion.
The tip having the movable contact and
A midway portion between the base portion and the tip portion and having an opening through which the insulating wall portion is inserted is provided.
The middle part is
The opening is sandwiched and opposed to each other in a direction orthogonal to the direction from the base portion to the tip portion when viewed from the moving direction of the movable contact by the opening / closing mechanism portion, and each is hung between the base portion and the tip portion. circuitry breaker you characterized in that it has a bridge portion of a pair passed. With fixed contacts with fixed contacts,
A movable contact having a movable contact facing the fixed contact,
An opening / closing mechanism that moves the movable contact to make contact and release between the fixed contact and the movable contact.
An arc extinguishing device that extinguishes the arc generated between the fixed contact and the movable contact,
An insulating wall portion that extends along the moving direction of the movable contact at a position closer to the opening / closing mechanism portion than the fixed contact and regulates the movement of the arc toward the opening / closing mechanism portion is provided.
The movable contact is
A base portion that is located closer to the opening / closing mechanism portion than the insulating wall portion and in which the acting force of the opening / closing mechanism portion acts in the extending direction of the insulating wall portion.
The tip having the movable contact and
A midway portion between the base portion and the tip portion and having an opening through which the insulating wall portion is inserted is provided.
The middle part is
It faces the opening in a direction orthogonal to the direction from the base portion to the tip portion when viewed from the moving direction of the movable contact by the opening / closing mechanism portion, and is hung between the base portion and the tip portion. Has a bridge part
The opening is
Is formed in a slit shape, circuits breakers you characterized in that the opposite side is open and the bridge portion side in the direction of the perpendicular. The bridge portion
The circuit breaker according to claim 1 or 2 , wherein the movable contact is formed in a U shape and is bent in a direction away from the fixed contact. The insulating wall portion
The circuit breaker according to any one of claims 1 to 3, wherein the circuit breaker is formed to a length existing inside the opening over the entire moving range of the movable contact by the opening / closing mechanism portion. vessel. A base portion and a cover portion are provided, and an insulating housing for accommodating the opening / closing mechanism portion and the arc extinguishing device is provided in the space formed by the base portion and the cover portion.
The insulating wall portion
The circuit breaker according to any one of claims 1 to 4 , wherein the circuit breaker is formed so as to project from the base portion of the insulating housing. The invention according to any one of claims 1 to 4 , wherein the fixed contact includes an insulating block formed by integrally forming a cover portion that covers the periphery of the fixed contact and the insulating wall portion. Circuit breaker.

Images