JPH06162909A - Switch - Google Patents

Abstract

PURPOSE:To provide a switch having a favorable current-limiting performance by providing an exhaust air passage for discharging air in a container. CONSTITUTION:A fixed contact 4 is composed of a first conductor part 4a connected to a terminal part 5, a second conductor part 4e having a fixed contact 3, and a third conductor part 4d. The third conductor part 4d is disposed on the other end part side of the position of the fixed contact 3 where a movable contact 2 of a movable contact 1 is not provided, and on the opposite side of the terminal part 5. The first conductor part 4a is disposed above the position of a contact touching surface when the contact is closed, and under the position of the contact touching surface when the contact is opened. A part of the first conductor part 4a which can be seen from a surface of the movable contact 2 when the contact is opened is coated with insulation 15. An inflow port 13a on the inner side of a container 12 for an exhaust air passage 13 for discharging air to the external from an inner part of the container is provided under the first conductor part 4a and on the terminal part 5 side of the fixed contact 3.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a switch, such as a circuit breaker, a current limiter, or an electromagnetic contactor, in which an arc is generated in a container when the current is cut off.

[0002]

2. Description of the Related Art FIG. 25 is a side view showing, for example, a circuit breaker as a conventional switch when the circuit breaker is open, FIG. 26 is a side view showing a state immediately after contact opening of the circuit breaker of FIG. 25, and FIG. It is a side view which shows the maximum open state of the movable contact in the circuit breaker of FIG. In the figure, reference numeral 1 denotes a movable contactor of a circuit breaker, and the movable contactor 1 rotates about a rotation fulcrum (rotation center) 14 of a base (see FIGS. 26 and 27). Is supported as. Reference numeral 2 denotes a movable contact fixed to one end (lower surface of the free end portion) of the movable contact 1, 3 is a fixed contact that comes in contact with and separates from the movable contact 2 by the rotation of the movable contact 1, and 4 is the fixed contact 3. The fixed contactor is provided at one end, and the shape configuration of the fixed contactor 4 will be described later.
Reference numeral 5 is a power source side terminal portion connected to the other end of the fixed contactor 4. Reference numeral 6 denotes an arc extinguishing plate, which functions to extend and cool the arc generated between the movable contact 2 and the fixed contact 3 when the movable contact 2 and the fixed contact 3 are separated. Reference numeral 7 is an arc-extinguishing side plate that holds the arc-extinguishing plate 6. Reference numeral 8 denotes a mechanism section for rotating the movable contactor 1. The mechanism section 8 has a built-in current detection section (not shown), and the current detection section operates by detecting a short-circuit current. Has become. Reference numeral 9 is a handle for manually operating the mechanism portion 8, 10 is a load side terminal portion, and 11 is a conductor for connecting the terminal portion 10 to the movable contact 1. Reference numeral 12 is a container for housing these circuit breaker components, and 13 is an exhaust hole provided in the wall of the container 12.

The shape of the fixed contact 4 will be described below. 25 to 27, the fixed contactor 4 includes a conductor portion 4a to which the terminal portion 5 on the power source side is connected and which extends in the horizontal direction, and the terminal portion 5 in the conductor portion 4a.
A vertical conductor portion 4b bent downward at an end portion on the opposite side, and a stepped lower conductor portion 4c extending horizontally from the lower end of the conductor portion 4b on the opposite side to the conductor portion 4a.
And a conductor portion 4d rising vertically from the tip of the conductor portion 4c, and the conductor portion 4a from the upper end of the conductor portion 4d.
It is formed integrally with a conductor portion 4e extending horizontally toward the side, and the fixed contact 3 is provided on the conductor portion 4e.

In the fixed contactor 4 having such a configuration, the conductor portion 4d connecting the lower conductor portion 4c with the fixed contact 3 side is movable from the position of the fixed contact 3 to the movable contact 1. The conductor portion 4e, which is located on the other end portion side where the contact point 2 is not fixed and is on the opposite side of the terminal portion 5 and has the fixed contact point 3
Is on the same horizontal plane as the conductor portion 4a having the terminal portion 5, and is located below the position of the contact surface when the movable contact 2 and the fixed contact 3 are closed. The fixed contactor 4 is used in an exposed state where the entire surface of the fixed contactor 4 is not insulated.

Next, the operation will be described. In the state of FIG. 25, the terminal portion 5 of the fixed contactor 4 is connected to the power source, and the terminal portion 10 on the load side is connected to the load. In this state, when the handle 9 is operated in the direction of the arrow B, the mechanism portion 8 operates and the rotating contact 1 descends and rotates about the rotation fulcrum 14 (see FIGS. 26 and 27) of the base. The movable contact 2 comes into contact with the fixed contact 3 to be in a closed state, and power is supplied from the power source to the load. In this state, the movable contact 2 is pressed against the fixed contact 3 with a prescribed contact pressure in order to ensure the reliability of energization.

When a short circuit accident occurs in the circuit on the load side of the circuit breaker and a large short circuit current flows in the circuit, the current detecting section in the mechanism section 8 detects this large current and the mechanism section is detected. 8 is activated. As a result, the movable contact 1 is rotated in the contact opening direction so that the movable contact 2 is separated from the fixed contact 3. At the time of such contact opening, as shown in FIG.
6 and FIG. 27, the movable contact 2 and the fixed contact 3
Arc A is generated between and.

However, normally, when a large current such as a short-circuit current flows, the electromagnetic repulsive force at the contact surfaces of the movable contact 2 and the fixed contact 3 becomes very strong, and the contact pressure applied to the movable contact 2 is overcome. In addition, the movable contactor 1 has a mechanism portion 8
Rotate in the contact opening direction without waiting for the operation. Therefore, the rotation causes the movable contact 2 and the fixed contact 3 to be separated from each other, and the arc A generated between the contacts 2 and 3 is extended by the arc extinguishing plate 6 and cooled. As a result, the arc resistance rises, and a short-circuit current that limits the short-circuit current to a small level occurs,
At the current zero point, the arc A is extinguished and the current interruption is completed.

The current limiting is very important for improving the protection function of the circuit breaker. In order to improve the current limiting performance, it is necessary to increase the arc resistance as described above.

A method often used to extend the arc in order to increase the arc resistance is, for example, Japanese Patent Laid-Open No.
This is a method of using a fixed contactor having a shape as disclosed in Japanese Unexamined Patent Publication No. 0-49533 and Japanese Unexamined Patent Publication No. 2-68831. The shapes of the fixed contacts shown in these publications are basically the same as the shapes of the fixed contact 4 shown in FIGS. The current path by this fixed contact 4 is shown in FIG.
5 to 27, from the power source side terminal portion 5 to the conductor portion 4
The fixed contact 3 is reached through a, 4b, 4c, 4d and 4e in order. In such a current path, the electromagnetic force exerted on the arc A by the current flowing through the current path 4e on the fixed contact 3 side of the fixed contact 4 is a force that extends the arc A toward the arc extinguishing plate 6. As a result, the arc resistance becomes higher and a circuit breaker with excellent current limiting performance can be obtained.

In order to improve the current limiting performance in the usual AC interruption, it is necessary to increase the arc resistance as described above, but in this case, the current still reaches the maximum value immediately after the contacts 2 and 3 are opened. The arc resistance must be increased before it becomes. Even if the arc resistance is increased after the current becomes large, the current is not easily limited due to the inertia effect of the current. On the contrary, since the current is high and the resistance is high, the arc energy generated in the circuit breaker is large and the circuit breaker is only severely damaged. Therefore, it is necessary to have a fixed contact shape in which the arc immediately after the contacts 2 and 3 are separated is greatly extended by a strong electromagnetic force and the arc resistance is rapidly increased.

[0011]

Since the conventional switch having a fixed contactor shape is constructed as described above, FIG.
As shown in 5 to 27, the arc A immediately after the contacts 2 and 3 are opened.
The electric current path of the fixed contactor 4 for generating an electromagnetic force that extends the power source side terminal portion 5 is separated on the same plane as the conductor portion 4a having the power source side terminal portion 5 on the fixed contact 3 side. And other current paths (conductor parts) 4a, 4b,
All of 4c and 4d generate an electromagnetic force that extends the arc A to the side opposite to the terminal portion 5. The electric currents of the conductor portions 4a and 4c flow in the opposite direction to the conductor portion 4e on the fixed contact 3 side, thereby generating an electromagnetic force that extends the arc A in the direction opposite to the direction of the terminal portion 5. Also, the conductor portion 4
The current of b repels each other due to the opposite direction of the current of the arc A, and the current of the conductor portion 4d is in the same direction as the current of the arc A and attracts each other. The result is stretching in the direction. Therefore, the electromagnetic force that extends the arc A generated by the current path 4e toward the terminal portion 5 is reduced. Therefore, in the shape of the fixed contactor 4 used in the conventional switch, there is a problem that the electromagnetic force of the current flowing through the fixed contactor 4 does not act effectively because it extends the arc.

The inventions of claims 1 to 3 have been made in order to solve the above problems, and have an excellent current limiting performance by disposing an exhaust passage for exhausting gas in a container. The purpose is to obtain a switch.

It is another object of the present invention to provide a switch having excellent current limiting performance by disposing a slit plate facing each other in the vicinity of the contact.

[0014]

In the switch according to the invention of claim 1, when the direction in which the movable contact in the contact closed state is separated from the fixed contact is upward, the fixed contact is used as a terminal portion. A contact surface of a fixed contact which is composed of a first conductor portion to be connected, a second conductor portion having a fixed contact, and a third conductor portion which vertically connects the first conductor portion and the second conductor portion, and which contacts the movable contact. Is arranged below the position of the terminal part, and the third conductor part is arranged from the position of the fixed contact to the other end side where the movable contact of the movable contact is not provided and to the opposite side of the terminal part. A portion of the first conductor portion which is arranged above the position of the contact contact surface when the contact is closed and below the position of the contact contact surface when the contact is opened, and which can be seen from the movable contact surface when the contact is opened. Exhaust flow that covers the inside with an insulator and exhausts from the inside of the container to the outside. The container inside the inlet in which are provided from the terminal portion side is and the fixed contact a lower side of the first conductor portion.

In the switch according to the second aspect of the invention, the arc runner is provided in the second conductor portion to which the fixed contact is fixed, and the inflow port is arranged near the tip of the terminal portion side of the arc runner.

In the switch according to the invention of claim 3, the inflow port is provided in the upper portion of the first conductor portion.

In the switch according to the invention of claim 4, when the direction in which the movable contact in the contact closed state is separated from the fixed contact is upward, the fixed contact is connected to the terminal portion. , A second conductor portion having a fixed contact, and a third conductor portion that connects the first conductor portion and the second conductor portion in the vertical direction, and the position of the contact surface of the fixed contact that contacts the movable contact is set to the position of the terminal portion. The third conductor portion is arranged below the position, the third conductor portion is arranged on the other end side where the movable contact of the movable contact is not provided and on the opposite side of the terminal portion from the position of the fixed contact, and the first conductor portion is connected to the contact point. It is arranged above the position of the contact contact surface when closed, and below the position of the contact contact surface when the contact is opened, and the portion of the first conductor part that can be seen from the movable contact surface when the contact is opened is covered with an insulator. , The part exposed to the arc near the contact,
The slit plates made of an insulating material are arranged so as to face each other so as to sandwich the contact from both sides, and the inlet of the exhaust passage for exhausting air from the inside of the container to the outside is located below the first conductor part. It is provided on the terminal side from the fixed contact.

In a switch according to a fifth aspect of the present invention, the inflow port is provided above the first conductor portion.

[0019]

In the switch according to the invention of claim 1, immediately after the contact is opened, the arc is directed in the direction of the terminal portion by all the electric current flowing through the conductor constituting the fixed contact and the air flow flowing into the inlet of the exhaust passage inside the container. A high arc voltage is generated and maintained by the extended and contacting of the arc with the insulator covering the inside of the cutout portion of the first conductor portion, and the internal pressure is reduced by the exhaust flow path to prevent container cracking.

In the switch according to the second aspect of the invention, the arc is stretched in the direction of the terminal portion immediately after the contact is opened by the entire current flowing through the conductors forming the fixed contact and the airflow flowing to the exhaust passage, The spot quickly transitions to the arc runner, greatly reducing the damage to the fixed contacts due to the arc,
A high arc voltage is generated and maintained by the arc touching the insulator covering the inside of the cutout portion of the first conductor portion, and the internal pressure is reduced by the exhaust flow path to prevent container breakage.

In the switch according to the third aspect of the invention, the exhaust airflow from between the contacts is directed to the upper side to suppress the wear of the movable contact and extend the arc, thereby accelerating the rotation of the movable contactor and increasing the arc voltage. Is generated and maintained, the internal pressure is reduced by the exhaust flow path, and the container is prevented from cracking.

In the switch according to the invention of claim 4, immediately after the contact is opened, the arc is directed in the direction of the terminal portion by all the current flowing through the conductor forming the fixed contact and the air flow flowing into the inlet of the exhaust passage inside the container. Stretched and arced first with slit plate
A high arc voltage is generated and maintained by touching the insulator covering the inside of the cutout portion of the conductor portion, the internal pressure is reduced by the exhaust flow path, and container cracking is prevented.

In the switch according to the invention of claim 5, the exhaust airflow from between the contacts is directed to the upper side to suppress the wear of the movable contact and extend the arc, thereby accelerating the rotation of the movable contactor and increasing the arc voltage. Is generated and maintained, the internal pressure is reduced by the exhaust flow path, and the container is prevented from cracking.

[0024]

【Example】

Example 1. An embodiment of the present invention will be described below with reference to the drawings. 1 is a side view showing a closed state of a circuit breaker according to an embodiment of the present invention, and FIG. 2 is a side view showing an open state of the circuit breaker of FIG. The same or corresponding parts will be denoted by the same reference symbols and redundant description will be omitted. In the figure, 4 is a fixed contactor having a fixed contact 3 provided at one end, and the fixed contactor 4 is the first conductor portion 4
a, a second conductor portion 4e, and a third conductor portion 4d.

More specifically, in the contact closed state of FIG. 1, when the direction in which the movable contact 2 of the movable contact 1 separates from the fixed contact 3 is upward, the fixed contact 4 is connected to the power source side. A first conductor portion 4a connected to the terminal portion 5 and extending in the horizontal direction, a second conductor portion 4e spaced below the first conductor portion 4a, a second conductor portion 4e and the first conductor portion 4a. Is integrally formed with a third conductor portion 4d which is vertically connected on the opposite side of the terminal portion 5, and the fixed contact 3 is fixed on the second conductor portion 4e.
Is located below the first conductor portion 4a.

The fixed contactor 4 has a fixed contact 3
The third conductor portion 4d is located on the other end side where the movable contact 2 of the movable contactor 1 is not fixed from the position of (3) and on the opposite side of the terminal portion 5 (the rotation center 14 side of the movable contactor 1). It is attached and set to the container 12 in the direction to do. in this case,
The first conductor portion 4a is located above the contact contact surface when the movable contact 2 is in contact with the fixed contact 3 when the contact is closed, and below the contact surface of the movable contact 2 when the contact is opened. is there. Reference numeral 15 is an insulator covering the first conductor portion 4a which is visible from the surface of the movable contact 2 when the contact is opened.

The arc-extinguishing plate 6 shown in FIGS. 1 and 2 has a notch (not shown) for not hindering the rotation of the movable contact 1. Further, 13 is an exhaust flow path for exhausting air from the inside of the container 12 to the outside, 13a
Is below the first conductor portion 4a and from the fixed contact 3 to the terminal portion 5
It is an inflow port inside the container of the exhaust flow path 13 provided on the side. 1 and 2, the mechanism portion 8, the handle 9 and the load side terminal portion 10 in the conventional circuit breaker shown in FIG. 27 are omitted, and these are naturally the container 1
It is stored and arranged in 2.

3 (a) and 3 (b) are perspective views showing a fixed contact according to an embodiment of the present invention. Figure 3
The fixed contactor 4 shown in (a) is integrally formed by the first conductor portion 4a, the second conductor portion 4e, and the third conductor portion 4d, and the terminal portion 5 is formed at the end portion of the first conductor portion 4a on the power supply connection side. Are connected. The fixed contact 3 is fixed to the upper surface of the second conductor portion 4e. Further, in the fixed contactor 4, the connecting conductor portions (first conductor portion 4a and third conductor portion 4d) located above the fixing surface of the fixed contact 3 have the second conductor portion 4e.
A slit 40 is provided so as not to interfere with the opening / closing operation of the movable contact 1 with respect to the upper fixed contact 3.

In FIG. 3B, 13 is an exhaust passage, and the inlet 13a of this exhaust passage 13 is the first conductor portion 4.
It is provided below a and closer to the terminal than the fixed contact 3.

Next, the operation will be described. When a large current such as a short-circuit current flows, the movable contact 1 rotates without waiting for the operation of the mechanism section, and the movable contact 2 and the fixed contact 3 are separated,
An arc is generated between the contacts 2 and 3 as in the conventional case. In FIG. 4, the contact surface of the movable contact 2 immediately after the contacts 2 and 3 are opened is still connected to the terminal portion 5 of the fixed contact 4.
The state is below the conductor portion 4a. Here, the arrow indicates the current, and the arc extinguishing plate 6 is omitted for simplicity. The current paths formed from the terminal portion 5 to the first conductor portion 4a of the fixed contact 4 are all above the arc A. As a result, the electromagnetic force acting on the arc generated by this current path is a force that extends the arc toward the terminal portion 5 side. Since the current flowing through the third conductor portion 4d of the fixed contactor 4 is in the opposite direction to the current of the arc, the electromagnetic force generated by the current flowing through the third conductor portion 4d is also a force that extends the arc toward the terminal portion 5 side. Further, high-pressure hot gas generated by the arc is introduced into the inflow port 13
It flows toward a and this force also tries to extend the arc toward the terminal portion 5 side. Therefore, the electromagnetic force generated by the current flowing through the fixed contact 4 and the air flow of the hot gas are all forces for extending the arc toward the terminal portion 5 side. As a result, the arc immediately after the contact is opened is strongly stretched, and the arc resistance rapidly increases.

FIG. 5 (a) is a side view of the movable contact and the fixed contact, and FIG. 5 (b) is C of the fixed contact in FIG. 5 (a).
FIG. 41 is the center of gravity of each cross section of the first conductor portion 4a on both the left and right sides of the slit 40. FIG. 5 (c)
Is a magnetic field strength distribution on the Z-axis of FIG. 5B, which is created by a current flowing through the fixed contactor 4 obtained by theoretical calculation. Figure 5
In (c), the magnetic field component in the positive direction extends the arc toward the terminal 5 side (hereinafter referred to as arc driving magnetic field).
Is. As shown in FIG. 5B, the first conductor portion 4a is located at a position displaced left and right from the plane on which the movable contact 1 rotates. In such a conductor arrangement, due to the influence of the current flowing through the second conductor portion 4e and the third conductor portion 4d, the space above the first conductor portion 4a (region Z0) is affected as shown in FIG. 5C.
There is an arc-driven magnetic field up to. Therefore, even if the movable contact surface is rotated above the first conductor portion 4a as shown in FIG. 6, the arc receives a force on the terminal side at the groove portion of the first conductor portion 4a and covers the inner portion of the groove. It is pressed against the insulator 15a and cooled. As a result, the arc resistance, which has suddenly increased immediately after contact opening, further increases and the high arc voltage is maintained, so that a circuit breaker having excellent current limiting performance can be obtained.

Further, the inlet 13a of the exhaust passage 13 according to this embodiment is closer to the arc generated between the contacts than the exhaust hole of the conventional example shown in FIG. It is possible to prevent the pressure inside the container from rising and prevent the container from cracking. Further, as another embodiment, the exhaust passage 13 has a terminal portion 5 as shown in FIGS. 7 and 8.
The same effect as that of the first embodiment can be obtained by arranging the side and the movable contact 1 on the rotation center 14 side.

Example 2. FIG. 9 is a side view showing a circuit breaker according to an embodiment of the present invention. In the figure,
Reference numeral 25 is an arc runner fixed to the first conductor portion 4a.
Reference numeral 5a is a tip portion of the arc runner 25 on the terminal portion 5 side, and 13a is an inlet arranged near the tip portion 25a of the arc runner on the terminal portion side. The arc generated between the contacts is instantly transferred to the arc runner by the strong driving magnetic field and the flow of the high-pressure hot gas toward the inflow port 13a, and is driven to the tip portion 25a, so that the arc is easily extended, wear of the fixed contact is reduced, and the arc is reduced. Is strongly pressed against the insulator 15 covering the inner part of the groove of the first conductor portion 4a, and the arc resistance is increased. In addition, inflow port 1
By providing 3s in the vicinity of the tip 25a on the terminal portion side of the arc runner 25, it is possible to quickly guide high-pressure hot gas to the exhaust passage and prevent the pressure inside the container from rising, prevent the container from cracking, and provide an excellent limit. A circuit breaker having flow performance and durability can be obtained.

Example 3. FIG. 10 is a side view showing a circuit breaker according to an embodiment of the present invention. In the figure, 13 is an exhaust flow path for exhausting air from the inside of the container 12 to the outside, and 13a is an inlet inside the container of the exhaust flow path 13 provided above the first conductor portion 4a. The arc generated between the contacts is stretched by the strong driving magnetic field, and the arc is strongly pressed against the insulator 5 covering the inner part of the groove of the first conductor portion 4a to increase the arc resistance, as in the first embodiment. However, since the flow of the high-pressure hot gas toward the inflow port 13a goes upward, the arc of the movable contact 2 moves to the upper movable contact tip 1a to reduce the wear of the movable contact, and
The arc is easily introduced into the arc extinguishing plate 6 and is cooled, so that the arc resistance becomes higher. Further, the flow of the high-pressure hot gas toward the inflow port 13a pushes up the movable contactor 1 to the upper part to accelerate the rotation speed, and a circuit breaker having excellent current limiting performance and durability can be obtained. Further, as another embodiment, the exhaust passage 13
The same effect can be obtained by forming the shape as shown in FIGS. 11 and 12 or by combining the first and third embodiments as shown in FIG.

Example 4. FIG. 14A is a side view showing a closed state of the circuit breaker according to an embodiment of the invention of claim 4, and FIG. 14B is a sectional view taken along line DD in FIG. 14A. In the figure, reference numeral 59 is a slit plate made of an insulating material, which sandwiches the contacts at narrow intervals from both sides. 13 is a container 12
The exhaust flow path for exhausting air from the inside to the outside, 13a is the first
It is an inflow port inside the container of the exhaust flow path 13 provided below the conductor portion 4a and closer to the terminal portion 5 than the fixed contact 3. Figure 1
5 shows a state in which the movable contact 1 is opened, and FIG.
16A is a perspective view of the fixed contactor 4 connected to the terminal portion 5, and FIG. 16B is a terminal portion 5, the fixed contactor 4, the insulator 1.
FIG. 5 is a perspective view showing 5, a slit plate 59 and an exhaust passage 13 at the same time.

FIG. 17A shows a state in which the contact surface of the movable contact 2 immediately after the contacts 2 and 3 are separated is still below the first conductor portion 4a connected to the terminal portion 5 of the fixed contactor 4. Shows. Here, the arrow indicates the current, and the slit plate 59 and the arc extinguishing plate 6 are omitted for simplicity. Terminal part 5 to fixed contact 4
The current paths formed up to the first conductor portion 4a of are all above the arc A. As a result, the electromagnetic force acting on the arc generated by this current path is a force that extends the arc toward the terminal portion 5 side. Since the current flowing through the first conductor portion 4d of the fixed contactor 4 is in the opposite direction to the current of the arc, the electromagnetic force generated by the current flowing through the third conductor portion 4d is also a force that extends the arc toward the terminal portion 5 side. Further, the high-pressure gas generated by the arc coming into contact with the slit plate 59 flows toward the inflow port 13a, and this force also tends to extend the arc toward the terminal portion 5 side. Therefore, the electromagnetic force generated by the current flowing through the fixed contact 4 and the gas flow are all forces that extend the arc toward the terminal portion 5. As a result, the arc immediately after the contact is opened is strongly stretched, and the arc resistance rapidly increases.

FIG. 17B is a sectional view taken along the line EE in the vicinity of the contact as seen from the terminal portion 5 side in FIG. 17A in the direction of the movable contact 1. Here, the movable contactor 1 shows a state in the middle of rotation. The arc generated between the contact points 2 and 3 touches the slit plate 59 arranged at a narrow interval on both sides of the contact point (hereinafter, the surface of the slit plate exposed to the arc is called a slit surface). When cooled, the arc voltage rises.
Further, at this time, the rotation speed of the movable contact 1 is increased due to the increase in the gas pressure of the gas emitted from the slit plate, and the extension of the arc becomes faster.

Further, as shown in FIG. 5C, due to the influence of the current flowing through the second conductor portion 4e and the third conductor portion 4c, the driving magnetic field exists up to the space Z0 above the first conductor portion 4a. , The arc receives a force on the terminal side, so that
Even if the movable contact surface is rotated to a position above the first conductor portion 4a as in 8, the arc receives a force on the terminal portion side in the groove portion of the first conductor portion 4a and covers the inner portion of the groove. It is pressed against and cooled. As a result, the arc resistance that has rapidly increased immediately after contact opening has increased, and a high arc voltage is maintained. Further, even if the movable contact surface rotates above the first conductor portion 4a, since the slit plate 59 is exposed to the arc, the rotation speed of the movable contact 1 is slowed down by the above gas pressure. It is possible to obtain a circuit breaker having excellent current limiting performance and excellent breaking performance.

In addition, the inlet 13a of the exhaust passage 13 according to the fourth embodiment is closer to the arc generated between the contacts than the exhaust hole of the conventional example shown in FIG. It is also possible to obtain the effect of preventing the cracking of the container by preventing the pressure inside the container from rising to 13. Further, as another embodiment, when the exhaust passage 13 is arranged on the terminal portion 5 side and the rotation center 14 side of the movable contact 1 as shown in FIGS. 19 and 20, the same effect as the above and Embodiment 4 is obtained. Is obtained.

Example 5. FIG. 21 is a side view showing a circuit breaker according to an embodiment of the present invention. In the figure, 13 is an exhaust flow path for exhausting air from the inside of the container 12 to the outside, and 13a is an exhaust flow path 1 provided on the first conductor portion 4a.
3 is an inlet inside the container. The arc generated between the contacts is stretched by the strong driving magnetic field, and the arc is strongly pressed against the insulator 15 covering the deep part of the groove of the first conductor portion 4a and the slit surface to increase the arc resistance. 4, but the arc of the movable contact 2 moves to the upper movable contact tip 1a to reduce the wear of the movable contact because the flow of the high-pressure hot gas toward the inflow port 13a is upward. The arc is easily introduced into the arc extinguishing plate 6 and is cooled, so that the arc resistance becomes higher. Further, the flow of the high-pressure hot gas toward the inflow port 13a pushes up the movable contactor 1 to the upper portion to accelerate the rotation speed, and a circuit breaker having excellent current limiting performance and durability can be obtained. Also, as another embodiment, the same effect can be obtained by forming the exhaust flow path 13 into a shape as shown in FIGS. 22 and 23, or combining the first and second embodiments as shown in FIG.

[0041]

As described above, according to the invention of claim 1, the inside of the container of the exhaust passage for exhausting from the inside of the container to the outside is below the inflowing first conductor portion and is closer to the terminal portion than the fixed contact. Since it is configured to be installed in the container, immediately after the contact is opened, the electromagnetic force generated by all the current paths of the fixed contact and the flow of the high-pressure hot gas toward the inlet inside the container of the exhaust flow path cause the arc to form the terminal part. It becomes a driving force to the side, the arc voltage can be rapidly raised, and even if the separation distance of the movable contact increases, the arc cooling action by the insulator of the cutout portion can generate and maintain a high arc voltage, Further, there is an effect that the high-pressure hot gas is promptly guided to the exhaust passage, the pressure inside the container is prevented from rising, the container is prevented from cracking, and the switch having excellent current limiting performance is obtained.

According to the second aspect of the invention, the arc runner is provided in the second conductor portion to which the fixed contact is fixed, and the inflow port is arranged in the vicinity of the tip of the arc runner on the terminal side. Immediately after that, the electromagnetic force generated by all the current paths of the fixed contact becomes the force that drives the arc toward the terminal side by the flow of the high-pressure hot gas toward the inlet inside the container of the exhaust flow path, and quickly moves the arc spot. It can be transferred to the arc runner to reduce the damage to the fixed contacts, extend the arc and rapidly raise the arc voltage, and even if the separation distance of the movable contact increases, the arc cooling effect of the insulator in the notch High arc voltage can be generated and maintained, and high-pressure hot gas can be quickly guided to the exhaust passage to prevent the pressure inside the container from rising, preventing the container from cracking and having excellent current limiting performance. There is an effect that 閉器 can be obtained.

According to the third aspect of the present invention, since the inflow port is provided above the first conductor portion, the electromagnetic force generated by all the current paths of the fixed contact causes an arc immediately after the contact is opened. It becomes a force to drive to the terminal part side, the arc can be extended and the arc voltage can be rapidly raised, and the arc of the movable contact moves to the tip of the upper movable contact to reduce wear of the movable contact and extinguish the arc. It is easily introduced into the plate and cooled to increase the arc resistance, and the flow of hot gas pushes the movable contact to the upper part to accelerate the rotation speed, resulting in a switch with excellent current limiting performance and durability. There is.

According to the fourth aspect of the present invention, the slit plates made of an insulating material are arranged at a narrow interval so as to sandwich the contacts from both sides at a portion exposed to the arc in the vicinity of the contacts, and the slit plates are arranged from the inside of the container to the outside. Since the inlet is provided below the first conductor and on the side of the terminal from the fixed contact inside the container of the exhaust flow path for exhaust, immediately after the contact is opened, all current paths of the fixed contact are The electromagnetic force that is created and the flow of the high pressure hot gas emitted by the slit plate toward the inlet inside the container of the exhaust flow path become the force that drives the arc to the terminal side, and the arc voltage can be rapidly raised. Even if the separation distance of the movable contact is increased, a high arc voltage can be generated and maintained by the arc cooling action of the insulator of the slit surface and the notch, and high-pressure hot gas can be quickly delivered to the exhaust passage. The pressure inside the container rises To prevent the prevent container cracks, the effect of switch is obtained with excellent current limiting performance.

According to the fifth aspect of the invention, since the inflow port is provided above the first conductor portion, the electromagnetic force generated by all the current paths of the fixed contact causes an arc immediately after the contact is opened. It becomes the driving force to the terminal side, the arc can be extended and the arc voltage can be rapidly raised, and the arc of the movable contact moves to the tip of the upper movable contact to reduce wear of the movable contact and extinguish the arc. It is easily introduced into the plate and cooled to increase the arc resistance, and the flow of hot gas pushes the movable contact to the upper part to accelerate the rotation speed, resulting in a switch with excellent current limiting performance and durability. There is.

[Brief description of drawings]

FIG. 1 is a side view showing a closed state of a circuit breaker according to an embodiment of the present invention.

FIG. 2 is a side view showing an open state of the circuit breaker according to the first embodiment of the invention.

FIG. 3 is a perspective view of a fixed contact of the circuit breaker according to the embodiment of the invention of claim 1;

FIG. 4 is an operation explanatory diagram of the circuit breaker according to the embodiment of the invention of claim 1;

FIG. 5 is an explanatory diagram of a magnetic field strength distribution generated by a current flowing through a fixed contact of the circuit breaker according to the embodiment of the invention of claim 1;

FIG. 6 is an operation explanatory view of the circuit breaker according to the embodiment of the invention of claim 1;

FIG. 7 is a side view showing a circuit breaker according to another embodiment of the present invention.

FIG. 8 is a side view showing a circuit breaker according to another embodiment of the present invention.

FIG. 9 is a side view showing a circuit breaker according to an embodiment of the invention of claim 2;

FIG. 10 is a side view showing a circuit breaker according to an embodiment of the invention of claim 3;

FIG. 11 is a side view showing a circuit breaker according to another embodiment of the invention of claim 3;

FIG. 12 is a side view showing a circuit breaker according to another embodiment of the invention of claim 3;

FIG. 13 is a side view showing a circuit breaker according to another embodiment of the invention as claimed in claim 3;

FIG. 14 is a side view showing a closed state of the circuit breaker according to the embodiment of the invention of claim 4;

FIG. 15 is a side view showing an open state of a circuit breaker according to an embodiment of the invention of claim 4;

FIG. 16 is a perspective view of a fixed contact of a circuit breaker according to an embodiment of the invention of claim 4;

FIG. 17 is an operation explanatory view of the circuit breaker according to the embodiment of the invention of claim 4;

FIG. 18 is an operation explanatory view of the circuit breaker according to the embodiment of the invention of claim 4;

FIG. 19 is a side view showing a circuit breaker according to another embodiment of the invention of claim 4;

20 is a side view showing a circuit breaker according to another embodiment of the invention as set forth in claim 4; FIG.

FIG. 21 is a side view showing a circuit breaker according to an embodiment of the invention of claim 5;

FIG. 22 is a side view showing a circuit breaker according to another embodiment of the invention of claim 5;

FIG. 23 is a side view showing a circuit breaker according to another embodiment of the invention of claim 5;

FIG. 24 is a side view showing a circuit breaker according to another embodiment of the invention as claimed in claim 5;

FIG. 25 is a side view showing an open state of a conventional circuit breaker.

26 is a side view showing a state immediately after the contacts of the circuit breaker of FIG. 25 are opened.

27 is a side view showing the maximum open state of the movable contact in the circuit breaker of FIG. 26.

[Explanation of reference numerals] 1 movable contactor 2 movable contact point 3 fixed contact point 4 fixed contactor 4a first conductor portion 4d third conductor portion 4e second conductor portion 5 terminal portion 13 exhaust passage 13a inlet port 15 insulator 25 arcrunner 59 Slit plate

 ─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Mitsugu Takahashi 8-1-1 Tsukaguchi Honcho, Amagasaki City Mitsubishi Electric Corporation Central Research Institute (72) Inventor Takao Mitsuhashi 8-1-1 Tsukaguchi Honmachi, Amagasaki Mitsubishi Electric Central Research Institute Co., Ltd.

Claims (5)

[Claims] 1. A movable contactor housed in a container and having a movable contact at one end, and a fixed contactor having a fixed contact at one end which can be brought into contact with and separated from the movable contact by opening and closing the movable contact. In a switch having a terminal portion connected to the other end of the fixed contact, when the movable contact in the contact closed state is set to the upward direction in which the movable contact is separated, the fixed contact is It is composed of a first conductor portion connected to the terminal portion, a second conductor portion having the fixed contact, and a third conductor portion connecting the first conductor portion and the second conductor portion in the vertical direction, and is in contact with the movable contact. The position of the contact surface of the fixed contact is disposed below the position of the terminal portion, and the third conductor portion is located on the other end side where the movable contact of the movable contact is not provided from the position of the fixed contact and the terminal. Is disposed on the opposite side to the first conductor part, and A portion of the first conductor portion that is located above the position of the contact contact surface and below the position of the contact contact surface when the contact is opened, and covers the portion of the first conductor portion that can be seen from the movable contact surface when the contact is opened is covered with an insulator. A switch which is provided below the first conductor portion and on the terminal portion side of the fixed contact, the inlet of the inside of the container of the exhaust flow path for exhausting from the inside of the container to the outside. . 2. The switch according to claim 1, wherein an arc runner is provided in the second conductor portion to which the fixed contact is fixed, and the inflow port is arranged in the vicinity of the tip of the arc runner on the terminal portion side. 3. The switch according to claim 1, wherein the inlet is provided in the upper portion of the first conductor portion. 4. A movable contactor having a movable contact at one end, a fixed contactor having a fixed contact at one end which can be brought into contact with and separated from the movable contact by opening and closing the movable contact, and a fixed contactor of the fixed contactor. In a switch having a terminal part connected to the other end, when the direction in which the movable contact in the contact closed state separates from the fixed contact is upward, the fixed contact is connected to the terminal part. Contact of the fixed contact, which comprises a first conductor portion, a second conductor portion having the fixed contact, and a third conductor portion that vertically connects the first conductor portion and the second conductor portion, and contacts the movable contact. The position of the surface is arranged below the position of the terminal portion, and the third conductor portion is located on the other end side where the movable contact of the movable contact is not provided and on the opposite side of the terminal portion from the position of the fixed contact. The first conductor portion is arranged at the position of the contact surface when the contact is closed. It is located above and located below the position of the contact surface when the contact is opened,
A portion of the first conductor part that can be seen from the surface of the movable contact when the contact is opened is covered with an insulator, and a slit plate made of an insulator is narrow so as to sandwich the contact from both sides in a portion exposed to an arc in the vicinity of the contact. The inflow port inside the container of the exhaust flow path for exhausting from the inside of the container to the outside is provided below the first conductor portion and on the terminal portion side of the fixed contact. Switch to be. 5. The switch according to claim 4, wherein the inlet is provided above the first conductor portion.