TWI446392B - Circuit breaker - Google Patents

Description

Circuit breaker

BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to a circuit breaker for wiring protection and the like, and more particularly to a circuit breaker having a direct-acting 2-contact configuration.

As a conventional circuit breaker, for example, there is a technique described in Patent Document 1. This technique is to provide a U-shaped magnetic body on the outer side of the movable contact and the fixed contact that have different current paths. According to such a configuration, when a large current such as a short-circuit current flows, an electromagnetic repulsion force (Laurz force) in the repulsive direction can be generated between the contacts, and the movable contact can be moved in a direction away from the fixed contact to improve the breaking performance. . Further, the arc generated between the contacts after the contact switch is opened can be moved toward the arc extinguishing device disposed on both end sides of the movable contact.

(previous technical literature) (Patent Literature)

[Patent Document 1] Japanese Patent No. 3859503

(Summary of the invention)

However, the electromagnetic force generated by the magnetic body is proportional to the current. Therefore, in the above-described conventional circuit breaker, a large electromagnetic force cannot be generated in a current region where the rated current is relatively small.

Therefore, in the low current region, the electromagnetic force that moves the arc generated when the contact switch is opened toward the arc extinguishing device is insufficient. Therefore, when the current is interrupted (when the contact switch is turned on), the arc system generated between the contacts must be interrupted in a short distance between the two contacts and in a stagnant state, and in order to have a DC circuit with no current zero. Corresponding to the voltage, there must be more contact switch opening distance. As a result, problems such as an arc extinguishing device and an increase in size of the product are caused.

Therefore, the present invention has been made to provide a circuit breaker that can appropriately move the arc between the contacts to the arc extinguishing device side even in a relatively small current region without increasing the size of the device.

In order to solve the above problems, the circuit breaker according to the first aspect of the patent application has: a pair of fixed contact pairs arranged to face each other at each pole; and a direct-acting movable contact bridge bridging the fixed contact; a pair of front and rear magnetic driving yokes each supporting a side portion of the movable contact, the circuit breaker being configured to press the movable contact on the fixed contact by a contact spring to make each pole pass The circuit is closed, and the movable contact is pressed by the opening and closing mechanism against the contact spring, and the movable contact is separated from the fixed contact to open the through circuit, wherein the magnetic drive yoke is permanently Made up of magnets.

Thereby, when the current is caused to flow through the movable contact in the closed state of the switch, the current is interlocked with the magnetic flux bundled by the magnetic driving yoke. The dynamic contact sub-system is subjected to a strong electromagnetic repulsive force (Laurz force) and is driven away from the fixed contact. Further, when the contact switch is turned on, although an arc is generated between the fixed contact and the movable contact, the arc is driven by the magnetic flux lock which is reinforced by the magnetic drive yoke, and is moved to the arrangement. The arc extinguishing device before and after the movable contact is arc extinguished.

Here, since the permanent magnet is used as the magnetic gas driving yoke, it is possible to have a certain magnetic flux regardless of the magnitude of the current. Therefore, even in a relatively small current region, the arc generated between the contacts when the contact switch is opened can be effectively driven toward the arc extinguishing device.

Further, in the circuit breaker of claim 2, in the invention of claim 1, the magnetic air drive yoke is formed of a U-shaped permanent magnet, and is configured to hold the movable contact by each of the two leg portions. The aforementioned side portion of the child.

In this way, since the magnetic driving yoke is constituted by the U-shaped permanent magnet, the U-shaped legs can surely hold the side portions of both ends of the movable contact, and since the magnetic driving yoke can be disposed at a desired position, The degree of freedom of configuration is large.

Further, in the circuit breaker of claim 3, in the invention of claim 1, the invention provides: an arc extinguishing device disposed before and after the movable contact; Interposed between the movable contact and the arc rectifying plate on which the foot end of the movable contact side of the arc between the fixed contact and the movable contact is rectified at the time of current interruption, the foregoing The arc rectifying plate has a pair of U-shaped magnetic shapes formed by bending toward the movable contact side The magnetic gas driving yoke is formed of a strip-shaped permanent magnet, and is fixed to the upper surface of both leg portions of the U-shaped magnetic body by the lower surface thereof, and is disposed to sandwich the side surface portion of the movable contact.

In this manner, since the magnetic air drive yoke is constituted by the strip-shaped permanent magnets, the size of the permanent magnet can be made smaller than in the case of the U-shaped permanent magnet. Therefore, the cost of this part can be reduced. Furthermore, since it is integrally formed with the arc rectifying plate, the number of components can be reduced, and the assembly of the circuit breaker can be simplified.

Further, in the circuit breaker of claim 4, in the invention of claim 1, the invention provides: an arc extinguishing device disposed before and after the movable contact; and spanning between the arc extinguishing devices And an arc rectifying plate that rectifies the foot end of the movable contact side of the arc between the fixed contact and the movable contact when the current is interrupted, and the arc rectifying plate has a movable contact toward the foregoing a pair of U-shaped magnetic bodies formed by bending the sub-side, wherein the magnetic gas driving yoke is formed of a strip-shaped permanent magnet, and is fixed to the inner surface of both leg portions of the U-shaped magnetic body, and is disposed to each hold the movable contact The aforementioned side portion of the child.

In this way, since the strip-shaped permanent magnets are fixed to the inner side surfaces of the leg portions of the U-shaped magnetic body formed by bending the arc rectifying plate, the number of the permanent magnets can be reduced as compared with the case where the front ends of the U-shaped magnetic bodies are fixed. Magnetic leakage of permanent magnets. As a result, the arc generated between the contacts when the contact switch is opened can be efficiently driven to the arc extinguishing device.

According to the present invention, since the permanent magnet is used as the magnetic gas driving yoke, even in a relatively small current region, the arc generated around the through circuit when the contact switch is opened can be surely moved toward the arc extinguishing device side. Therefore, it contributes to the provision of a small-sized circuit breaker suitable for a DC circuit and the miniaturization of a product body, and it is possible to provide a low-cost circuit breaker by sharing parts of an AC-specific product.

Hereinafter, embodiments of the present invention will be described based on the drawings.

(First embodiment) (constitution)

Fig. 1 is a cross-sectional view showing a current interruption portion of a circuit breaker according to the present invention. Among them, the circuit breaker of the present invention is a circuit breaker having a direct-acting type 2 contact.

In the figure, the symbol 1 is a current interruption portion. In each of the communication circuits, U-shaped fixed contacts 2, 3 made of a rectangular conductor are arranged in the front-rear direction, and fixed contacts 2a, 3a are attached to each of them. The strip-shaped movable contact members 4 which are bent in a U-shape at both ends have a pair of movable contacts 4a and 4b which can be in contact with the fixed contacts 2a, 3a, respectively. The movable contact 4 is pressed toward the fixed contacts 2 and 3 by a contact spring 5 composed of a compression spring in a switch-closed state in which the switch is closed, and each of the movable contacts 4a and 4b and the fixed contact 2a 3a contact, bridge fixed contact 2, 3 between. On the other hand, in the open state of the open switch circuit, the movable contact 4 is pressed downward by the opening and closing mechanism (not shown) against the contact spring 5 to be separated from the fixed contact 2, 3.

Further, a pair of arc extinguishing means 6 are disposed in front of and behind the movable contact 4, and a plurality of block gates 7 surround both ends of the movable contact 4. The grid 7 is composed of a U-shaped magnetic plate in the above figure, and is supported by the side walls 8 of a pair of left and right insulators. Further, an arc rectifying plate 9 made of a high-resistance material such as a steel plate is provided below the arc extinguishing device 6 so as to cross the front and rear arc extinguishing devices 6, and the arc rectifying plate 9 also serves as a receiving plate for the contact spring 5.

Reference numeral 10 in the figure is a pair of front and rear magnetic air drive yokes composed of U-shaped permanent magnets. The magnetic driving yoke 10 is disposed such that the side portions of both ends of the movable contact 4 are held by the left and right leg portions. Further, one of the left and right leg portions is an S pole, and the other leg portion is an N pole, and is arranged to have a polarity as shown in FIG. The left and right leg portions of the magnetic air drive yoke 10 are covered with an insulating cover 11.

Fig. 2 is an exploded perspective view showing the structure of the magnetic air drive yoke portion including the arc rectifying plate 9, the magnetic gas driving yoke 10, and the insulating cover 11.

The insulating cover 11 is formed of a resin and is formed in a U shape having a pair of right and left side walls 11a and 11b, and the movable contact 4 is held between the side walls 11a and 11b so as to be movable in the opening and closing direction (up and down direction of FIG. 1). . A pocket portion having an opening in the lower surface is formed in each of the side walls 11a and 11b of the insulating cover 11. These pockets cover the legs 10a, 10b of the magnetic drive yoke 10 when the circuit breaker is assembled. Further, the arc rectifying plate 9 is disposed on both legs of the magnetic air driving yoke 10 when the circuit breaker is assembled. Between the portions 10a and 10b, the outer surface of the lower surface of the insulating cover 11 is also provided.

(action)

Next, the first embodiment will be described with reference to the third to sixth embodiments.

3 is a cross-sectional view showing the structure of the current interrupting portion of the contact switch closing position, FIG. 4 is a cross-sectional view of the vicinity of the joint, and FIG. 5 is a top view of the vicinity of the joint, and FIG. 6 is a display The current interrupting portion structure of the contact switch open position and the drawing of the arc traveling direction.

In the switch-off state shown in Fig. 3, as shown by the direction of the arrow in the figure, it is a large current I whose current is a short-circuit current. At this time, as shown in FIG. 4, when the current I flows through the movable contact 4 from the top to the bottom in the direction perpendicular to the plane of the drawing of FIG. 4, the magnetic flux Φ according to the current I utilizes the magnetic gas. The drive yoke 10 is bundled and rotated clockwise through the movable contact 4 and the magnetic air drive yoke 10. At this time, since the magnetic flux Φ passing through the movable contact 4 from the left to the right of FIG. 4 vertically intersects the current I flowing through the movable contact 4, according to Fleming's left-hand rule, in the movable contact 4 As shown in Fig. 4, the electromagnetic repulsive force (Laurz force) F1 is moved downward.

At the same time, an overcurrent detecting device (not shown) detects an overcurrent and outputs a trip signal, and receives the signal to cause the opening and closing mechanism to push the movable contact 4 downward in the downward direction of FIG. Thereby, the fixed contacts 2a and 3a of the fixed contacts 2 and 3 and the movable contacts 4a and 4b of the movable contact 4 are tripped.

Therefore, the movable contact 4 is driven to open and close at a higher speed than that of a single electromagnetic repulsive force or a separate opening and closing mechanism. Therefore, only this can improve the breaking performance.

Further, when the contact switch that trips the fixed contacts 2a and 3a and the movable contacts 4a and 4b is opened, an arc is generated between the fixed contacts 2 and 3 and the movable contact 4. As shown in Fig. 5, the arc A is perpendicularly intersected with the magnetic flux reinforced by the magnetic driving yoke 10 (the magnetic flux passing from the left to the right of Fig. 4) Φ, according to Fleming's left-hand rule, In the arc A, the force F2 toward the outer side in the front-rear direction of the movable contact 4 is operated. As a result, as shown in FIG. 6, the arc A generated between the contacts moves toward the arc extinguishing device 6 side disposed on the outer side in the front-rear direction of the movable contact 4 by the arc A1 → the arc A2 → the arc A3 → the arc A4 . The arc A that is pulled into the arc extinguishing device 6 is analyzed. Cool and extinguish the arc to end the short circuit breaking action.

At this time, since the arc rectifying plate 9 is provided, the foot end of the movable contact 4 side of the arc A moves on the arc rectifying plate 9, and the arc A is extinguished in a state where the current does not flow through the movable contact 4, and can be suppressed. Damage to the movable contact 4 due to large current.

However, conventionally, a magnetic body has been used as a magnetic gas drive yoke.

Fig. 13 is a view showing a structure of a current interruption portion of a conventional circuit breaker, wherein (a) is a top view of the current interruption portion, and (b) is a front view of the current interruption portion. Here, an example in which the magnetic air drive yoke 110 composed of a magnetic body is integrally formed with the arc rectifying plate 109 is shown. In other words, the pair of front and rear magnetic air drive yokes 110 are integrally bent at the arc rectifying plate 109, and are oriented The switch of the movable contact 104 opens and moves in an upright direction.

According to such a configuration, when a large current such as a short-circuit current flows, as in the present embodiment, an electromagnetic force in the repulsive direction is generated between the contacts, and the movable contact 104 can be moved in a direction away from the fixed contact. When the contact switch is opened, the electromagnetic force that causes the arc generated between the contacts to move toward the arc extinguishing device can be generated.

However, since the electromagnetic force generated by the magnetic body is proportional to the current, when a magnetic body is used as the magnetic gas driving yoke, a large electromagnetic force cannot be generated in a relatively small current region around the rated current, and it is impossible to make it impossible. The arc generated when the contact switch is opened is properly moved toward the arc extinguishing device. Therefore, when the current is interrupted (when the contact switch is turned on), the arc system generated between the contacts must be interrupted in a short distance between the two contacts and in a stagnant state, and in order to have a DC circuit with no current zero. Corresponding to the voltage, there must be more contact switch opening distance. As a result, there is a problem that the arc extinguishing device and the product are enlarged.

In this regard, in the present embodiment, since the permanent magnet is used as the magnetic gas driving yoke, a certain electromagnetic force can be generated regardless of the magnitude of the current. Therefore, even in a relatively small current region where the rated current is relatively small, a sufficient electromagnetic force can be generated, and the arc generated when the contact switch is opened can be moved toward the arc extinguishing device.

As shown above, it is possible to achieve a current interruption in the effective use of an arc extinguishing device having a circuit breaker in a wider range of current regions.

(effect)

In the first embodiment, the magnetic flux driving yokes are arranged in a pair of front and rear sides so that the side faces of the movable contactors are held, and when the current is passed through the movable contactor in the closed state of the switch, the contact is fixed A strong electromagnetic repulsive force (Laurent force) is generated between the contactable members, so that the movable contact is driven away from the fixed contact. Also, when the contact switch is turned on, the Lawrence force can be used to drive the arc generated between the contacts toward the arc extinguishing device.

At this time, since the permanent magnet is used as the magnetic gas driving yoke, it is possible to have a certain magnetic flux regardless of the magnitude of the current. Therefore, even in a relatively small current region, it is possible to cause the arc between the contacts to be efficiently driven toward the arc extinguishing device when the contact switch is opened.

Therefore, for a DC disconnection in a low current region corresponding to a difficult configuration in the conventional structure, a wide range of current interruption using the arc extinguishing device can be achieved. Therefore, it contributes to the provision of a small arc extinguishing device to which a DC circuit is applied and the miniaturization of the product body, and it is possible to increase the number of parts shared with the AC-specific products, and to realize a low-cost circuit breaker.

Further, since the magnetic driving yoke is constituted by the U-shaped permanent magnet, the side faces of both ends of the movable contact can be surely held by the U-shaped legs. Further, since the magnetic air driving yoke is a separate member, the arc rectifying plate can be formed into a belt shape, and the arc rectifying plate can be easily formed and magnetically made as compared with the case where the arc rectifying plate is integrally formed. The degree of freedom in the arrangement of the air drive yoke becomes large.

Furthermore, during the opening operation of the contact switch, although the conductive gas according to the high pressure generated by the arc is filled in the vicinity of the contact point, By completely covering the legs of the magnetic gas driving yoke with the insulating cover, the occurrence of the phase-to-phase short circuit of the magnetic gas driving yoke can be prevented.

(Second embodiment)

Next, a second embodiment of the present invention will be described.

In the first embodiment, the magnetic air drive yoke 10 to which the U-shape is applied is formed by integrally forming the magnetic air drive yoke 10 and the arc rectifying plate 9.

(constitution)

Fig. 7 is a cross-sectional view showing the structure of the current interrupting unit 1 of the second embodiment.

As shown in Fig. 7, the current interrupting unit 1 of the present embodiment is connected to the current interrupting unit 1 shown in Fig. 1, except that the configuration of the magnetic driving yoke portion is different, and the current interrupting circuit of Fig. 1 is provided. Part 1 has the same configuration. Therefore, the same components as those in the first embodiment are denoted by the same reference numerals, and the description will be focused on the different components.

In the present embodiment, the arc rectifying plate 19 is used instead of the arc rectifying plate 9, and a magnetic gas driving yoke 20 is used instead of the magnetic driving yoke 10.

Fig. 8 is an exploded perspective view showing the structure of the magnetic air drive yoke portion of the second embodiment.

As shown in FIG. 8, the both ends of the movable contact 4 in the front-rear direction of the arc rectifying plate 19 are each formed to be bent toward the movable contact 4 side. U-shaped magnetic bodies 19a, 19b which are curved.

Further, the magnetic air drive yoke 20 is formed of a strip-shaped permanent magnet, and is fixed to the upper surface of both leg portions of the U-shaped magnetic bodies 19a and 19b of the arc rectifying plate 19 by the lower surface thereof, and is integrally formed with the arc rectifying plate 19. At this time, the magnetic driving yoke 20 is disposed in the wide direction (left-right direction) of the movable contact 4, and is formed such that the polarities are opposite to each other as shown in FIG.

In the state in which the magnetic circuit drive yoke 20 is fixed to the upper surfaces of the leg portions of the U-shaped magnetic bodies 19a and 19b formed on the arc rectifying plate 19, the magnetic yoke yoke 20 is formed in the same manner as in the first embodiment. The insulating cover 11 covers the U-shaped magnetic bodies 19a and 19b and the magnetic air driving yoke 20.

Thereby, the side surface portions of the movable contact 4 are held by the magnetic air driving yokes 20 which are fixed to the both leg portions of the U-shaped magnetic bodies 19a and 19b. In other words, the leg portions of the U-shaped magnetic bodies 19a and 19b are formed to be short in such a manner that the magnetic driving yoke 20 is disposed in the movable range of the movable contact 4 .

(action)

Next, the operation of the second embodiment will be described.

In the switch-off state, when a large current such as a short-circuit current flows, the fixed contacts 2a and 3a of the fixed contacts 2 and 3 and the movable contacts 4a and 4b of the movable contact 4 are tripped, in a fixed contact An arc is generated between the children 2 and 3 and the movable contact 4.

The arc A is as shown in Fig. 9, and is interlocked with the magnetic flux Φ which is reinforced by the magnetic driving yoke 20, and is oriented toward the movable contact 4 in the arc A. The force F2 on the outer side in the front-rear direction moves. Thereby, the arc A is moved to the arc extinguishing device 6 disposed on both end sides of the movable contact 4.

In this manner, as in the first embodiment described above, the arc generated around the through circuit when the contact switch is opened can be appropriately moved toward the arc extinguishing device side.

(effect)

As described above, in the second embodiment, since the magnetic air drive yoke and the arc rectifying plate are integrally formed, assembly or component management of the circuit breaker can be facilitated.

Further, since the magnetic driving yoke has a strip shape, the size of the permanent magnet can be made smaller than that of the U-shaped magnetic gas driving yoke in the first embodiment, and the cost of the portion can be reduced.

(Third embodiment)

Next, a third embodiment of the present invention will be described.

According to the third embodiment, in the second embodiment, the magnetic driving yoke is fixed to the upper surface of the U-shaped magnetic body formed on the arc rectifying plate, and is fixed to the U-shaped magnetic body. The inside surface of both feet.

(constitution)

The current interrupting unit 1 of the present embodiment is different from the current interrupting unit 1 shown in Fig. 8 except that the configuration of the magnetic driving yoke portion is different. The current interruption unit 1 of Fig. 8 has the same configuration. Therefore, the description will be centered on the different parts of the configuration.

Fig. 10 is an exploded perspective view showing the structure of the magnetic air drive yoke portion of the third embodiment.

As shown in FIG. 10, U-shaped magnetic bodies 29a and 29b which are bent and formed toward the movable contact 4 side are formed at both end positions of the movable contact 4 in the front-rear direction of the arc rectifying plate 29. Further, a step portion 29c for fixing the magnetic air driving yoke 30 is formed inside the leg portions of the U-shaped magnetic bodies 29a and 29b.

The magnetic air drive yoke 30 is constituted by a strip-shaped permanent magnet having the same thickness as the step portion 29c, and is integrally formed with the arc rectifying plate 29 by being fixed to the step portion 29c formed in the arc rectifying plate 29. In other words, the magnetic air drive yoke 30 is fixed to the inner side surfaces of the leg portions of the U-shaped magnetic bodies 29a and 29b. At this time, the magnetic driving yoke 30 is disposed in the width direction (left-right direction) of the movable contact 4, and the polarity shown in FIG. 11 is formed, and the dissimilar magnetic poles are arranged to face each other.

In the state in which the magnetic circuit drive yoke 30 is fixed to the step portion 29c formed in the arc rectifying plate 29, the insulating cover 11 having the same configuration as that of the first and second embodiments covers the U-shaped magnetic body. The bodies 29a and 29b and the magnetic gas drive yoke 30.

Thereby, the side surface portion of the movable contact 4 is held by the magnetic air driving yoke 30 which is fixed to both leg portions of the U-shaped magnetic bodies 29a and 29b. In other words, the both leg portions of the U-shaped magnetic bodies 29a and 29b are formed to be long so that the magnetic gas driving yoke 30 is disposed in the movable range of the movable contact 4 .

(action)

Next, the operation of the third embodiment will be described.

In the switch-off state, when a large current I such as a short-circuit current flows, the fixed contacts 2a and 3a of the fixed contacts 2 and 3 and the movable contacts 4a and 4b of the movable contact 4 are tripped, and are fixed. An arc is generated between the contacts 2 and 3 and the movable contact 4.

As shown in FIG. 11, the arc A is interlocked with the magnetic flux Φ that is reinforced by the magnetic driving yoke 30, and the force F2 toward the outer side in the front-rear direction of the movable contact 4 is operated in the arc A. Thereby, the arc A is moved to the arc extinguishing device 6 disposed on both end sides of the movable contact 4.

As described above, similarly to the first and second embodiments described above, the arc generated around the through circuit when the contact switch is opened can be appropriately moved toward the arc extinguishing device side.

However, as shown in the second embodiment, when the magnetic driving yoke 30 is fixed to the upper surfaces of the both leg portions of the U-shaped magnetic bodies 19a and 19b formed on the arc rectifying plate 19, as shown in Fig. 12, A leakage flux Φ' from the permanent magnet is generated. For this reason, the electromagnetic force for driving the arc A generated between the contacts toward the arc extinguishing device 6 side cannot be effectively generated.

On the other hand, in the present embodiment, the magnetic driving yoke 30 composed of the permanent magnets is fixed to the inner side surfaces of the leg portions of the U-shaped magnet bodies 29a and 29b. In other words, the U-shaped magnet bodies 29a and 29b are disposed outside the magnetic gas driving yoke 30 made of a permanent magnet. For this reason, as shown in Fig. 12, the leakage flux Φ' of the permanent magnet can be reduced, which can be effectively generated for use in The arc A generated between the contacts is directed toward the electromagnetic force driven by the arc extinguishing device 6 side.

(effect)

As described above, in the third embodiment, since the magnetic air drive yoke and the arc rectifying plate are integrally formed, assembly of the circuit breaker or component management can be facilitated.

Further, since the magnetic driving yoke has a strip shape, the size of the permanent magnet can be made smaller than that of the U-shaped magnetic gas driving yoke in the first embodiment, and the cost of the portion can be reduced.

Furthermore, since the magnetic driving yoke is fixed to the inner side surface of the leg portions of the U-shaped magnet of the arc rectifying plate, the magnetic leakage from the permanent magnet can be reduced, and the arc generated between the contacts can be effectively directed toward the arc extinguishing device side. mobile.

Further, since the magnetic driving yoke is fixed to the stepped portion of the U-shaped magnetic body formed in the arc rectifying plate, the thickness of the permanent magnet can be made thinner than the magnetic driving yoke of the second embodiment, and the portion can be reduced. The cost of the share. Further, since the magnetic driving yoke can be adsorbed to the step portion, the positioning of the magnetic driving yoke is changed as compared with the case where the magnetic driving yoke is simply fixed to the inner side surface of the leg portions of the U-shaped magnetic body without the step difference. It is easy to simplify assembly.

1‧‧‧current circuit breaker

2‧‧‧Fixed contact

3‧‧‧Fixed contact

2a, 3a‧‧‧ fixed joints

4‧‧‧ movable contact

4a, 4b‧‧‧ movable joints

5‧‧‧Contact spring

6‧‧‧Arc extinguishing device

7‧‧‧Gate

8‧‧‧ side wall

9‧‧‧Arc rectification board

10‧‧‧Magnetic drive yoke

10a, 10b‧‧‧ feet

11‧‧‧Insulation cover

11a, 11b‧‧‧ side wall

19‧‧‧Arc rectification board

19a, 19b‧‧‧U-shaped magnetic body

20‧‧‧Magnetic drive yoke

29‧‧‧Arc rectification board

29a, 29b‧‧‧U-shaped magnetic body

29c‧‧‧Departure

30‧‧‧Magnetic drive yoke

Fig. 1 is a cross-sectional view showing the structure of a current interruption portion of a circuit breaker according to the present invention.

Fig. 2 is a view showing the structure of the magnetic air drive yoke portion of the first embodiment. Decompose the perspective view.

Fig. 3 is a cross-sectional view showing the structure of the current interruption portion in the closed position of the contact switch.

Fig. 4 is a cross-sectional view of the vicinity of the contact and a vector diagram of current, magnetic flux, and electromagnetic repulsive force in the first embodiment.

Fig. 5 is a top view of the vicinity of the contact in the first embodiment and a vector diagram of current, magnetic flux, and electromagnetic repulsive force.

Fig. 6 is a view showing the structure of the current interruption portion and the arc traveling direction in the contact switch open position of the first embodiment.

Fig. 7 is a cross-sectional view showing the structure of the current interrupting portion of the second embodiment.

Fig. 8 is an exploded perspective view showing the structure of the magnetic air drive yoke portion of the second embodiment.

Fig. 9 is a top view of the vicinity of the contact in the second embodiment and a vector diagram of current, magnetic flux, and electromagnetic repulsive force.

Fig. 10 is an exploded perspective view showing the structure of the magnetic air drive yoke portion of the third embodiment.

Fig. 11 is a top view of the vicinity of the contact in the third embodiment, and a vector diagram of current, magnetic flux, and electromagnetic repulsive force.

Figure 12 is a diagram showing the magnetic leakage from the magnetic drive yoke.

Figure 13 is a diagram showing the construction of a current interrupting portion of a conventional current circuit breaker.

9‧‧‧Arc rectification board

10‧‧‧Magnetic drive yoke

10a, 10b‧‧‧ feet

11‧‧‧Insulation cover

11a, 11b‧‧‧ side wall

Claims (2)

A circuit breaker having, at each pole, a pair of front and rear fixed contact members arranged to face each other; a direct-acting movable contact member bridging the fixed contact; configured to each hold a side portion of the movable contact a pair of front and rear magnetic driving yokes configured to press the movable contact on the fixed contact by a contact spring to make the pole-connected circuits closed, and to overcome the aforementioned contact by the opening and closing mechanism The movable contact is pressed by the spring, and the movable contact is separated from the fixed contact to open the through circuit, wherein the magnetic drive yoke is formed of a permanent magnet, and is disposed before and after the movable contact a pair of arc extinguishing devices; disposed above the movable contact member across the arc extinguishing device, and movable in the arc between the fixed contact and the movable contact when the current is broken An arc rectifying plate for rectifying the foot end of the contact side, the arc rectifying plate having a side bent toward the movable contact Forming a pair of U-shaped magnetic bodies, wherein the magnetic gas driving yoke is formed of a strip-shaped permanent magnet, and the lower surface thereof is fixed to the upper surfaces of the leg portions of the U-shaped magnetic body, and is configured to hold the aforementioned The aforementioned side portion of the movable contact. The circuit breaker according to claim 1, further comprising: a pair of arc extinguishing devices disposed before and after the movable contact; and disposed under the movable contact so as to span between the arc extinguishing devices, and Will occur in the aforementioned fixed contact and the aforementioned movable when the current is broken An arc rectifying plate on which the foot end of the movable contact side of the arc between the contacts is rectified, wherein the arc rectifying plate has a pair of U-shaped magnetic bodies bent toward the movable contact side, and the magnetic driving yoke is driven The strip-shaped permanent magnet is fixed to the inner side surfaces of the leg portions of the U-shaped magnetic body, and is disposed to sandwich the side surface portions of the movable contact members.