JPH0334234A - Circuit breaker - Google Patents

Abstract

PURPOSE:To increase opening and closing speed by rotating a limit current contact base by use of an electromagnetic reaction generated on both sides of its rotating center as a couple, and connecting the other end of the end part facing a movable contact base to one end part of a terminal base by a flexible conductor. CONSTITUTION:When a handle 3 is tilted to the power source side, a movable contact base 9 is rotated with a pin 16 as the center through the counterclockwise rotations of an opening and closing mechanism 4 and an interlocking shaft 7, and a movable contact 10 is made into contact with a current-limiting contact 11. A current-limiting contact base 12 is provided with a return spring 13 for clockwise energizing a pin, and one end of the spring 13 is engaged with a mold case, and the other end to a contact base 12a. The contact base 12a is connected to the end part 15a of a terminal base 15 by a flexible copper strand 13. The pressures of the contacts 10, 11 are given by a spring 8 having the pin 16 of the rotating center of the movable contact base 9 as a shaft. When a large current is sent, electromagnetic reactions are formed in two positions between a power source terminal base 15 and the current-limiting contact base 12a and between the contact base 12b and the movable contact base 9, and the current-limiting contact base 12 is separated counterclockwise with a pin 17 as the center at a high speed by the couple. After the cut-off is completed, it is returned by a spring 13. According to this constitution, a high speed opening at 3 times or more the conventional speed can be realized.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a circuit breaker, particularly its electromagnetic repulsion current limiting mechanism, and improves the opening speed of the contact block at the time of interruption and further reduces the temperature rise of the contact portion. The structure is suitable for keeping the temperature low and improving reliability.

[Conventional technology]

Conventional MA of this kind is, for example, Utility Model Application Publication No. 52-4518
As described in No. 4, there are two contact points, and the number of parts is doubled. In addition, in terms of performance, since there are contacts, it is not possible to reduce the distance between conductors with opposite current directions to generate electromagnetic repulsion, and since there are two contacts, no consideration is given to temperature rise.

However, in other conventional devices, due to the electromagnetic force generated by the N flow that passes through the rear part of the movable contact block when shutting off,
This method uses a separate core to move and shoot. In this type of device, no consideration is given to the time delay caused by core suction when shutting off. That is, the performance is greatly influenced by the extremely short initial opening time of 0.1 to 0.2 m5ec at the time of interruption. Therefore, the time delay in core suction can be an important point.

Furthermore, since the core is composed of separate parts, no consideration has been given to the number of parts or the quality of the product.

References for this type of technology include
445, Japanese Utility Model Application No. 60-178856, and the like.

[Problem to be solved by the invention]

The above-mentioned conventional technology does not take into consideration the problem of the temperature of the contact portion and the effect of electromagnetic repulsion.

SUMMARY OF THE INVENTION An object of the present invention is to provide a circuit breaker equipped with an electromagnetic repulsion current limiting mechanism that is mass-producible and highly reliable by solving the above-mentioned problems of the prior art.

In the two-contact contact method, due to the problem of temperature rise, it is necessary to provide wiping (the edge between the contacts at the time of contact) on both sides of the contact, so not only the contacts but also the contact base which is a component part are required.
twice as necessary. Furthermore, because the springs and the like of the provided contact base are located inside the arc extinguishing chamber, they are susceptible to damage when the circuit is cut off, which poses a problem in terms of reliability. In addition, in other conventional technologies, when the iJ flow that passes through the circuit is used to project the movable contact block with other parts, there is a time delay until the core is attracted during the circuit, especially in the initial drive of current-limiting breakers, etc. This is an important point for current limiting circuit breakers, which poses a problem in terms of effectiveness.

In order to solve these problems mentioned above, in the present invention, one end of the terminal block is extended to the bottom of the main body mechanism part, a contact block is arranged opposite to it, and this opening gap is made extremely small to prevent electromagnetic repulsion. Made it possible to increase power. In addition, as a measure against temperature, by connecting one end with a flexible conductor wire, there is no need to wipe the contacts, and improvements have been made in terms of the number of parts and reliability against temperature.

In terms of the current-limiting effect at the time of interruption, the electromagnetic repulsion force is generated as a couple at both ends of the contact block, and the contact block is integrated.Also, due to the previous measures, the direction of the 'WL flow is different. By taking care not to reduce the distance between the conductors, we were able to close the contact block quickly and increase the arc voltage without any time delay in response to the current passing through the circuit.

[Means to solve the problem]

In order to achieve the above object, an array of contact points is located at the bottom of the mechanism part, and one end of the contact point is connected with a flexible conductive wire. One end of the jointed contact block is located on the opposite side to the center of rotation of the contact block of the open contact portion, and an electromagnetic repulsion force is generated as a couple with respect to the center of rotation.

Furthermore, the contact pressure spring that holds the contact block, and the joint between the terminal block and the contact block, are installed in a room separated from the arc extinguishing chamber, and are subject to damage due to arc heat generated during disconnection. This was done to prevent this from happening.

[Effect]

The main body mechanism is operated by moving a movable contact block by turning the operating handle ON and OFF.A current-limiting contact is placed in contact with the movable contact located at the tip of this movable contact block.
The current-limiting contact block is provided so that the current direction of the energizing current is opposite to that of the movable contact block. A return spring that urges the contact block in a clockwise direction is provided in the pin that rotationally holds the contact block, and the current-limiting contact block extends in a direction opposite to the contact side of the center of rotation.

This one end is connected to the alloy part extending from the power supply terminal by a flexible conductor. Are these parts electrically connected to each other? The current direction is opposite to the current direction.

Now, when a short circuit current flows during interruption, the contact part and the opposite part of the rotation fulcrum of the contact block generate an electromagnetic repulsion force due to the position of the base metal provided on each. It is configured to act as a couple with respect to the center of rotation. As a result, the opening speed of the contact block is approximately 3 times faster than that of conventional products.
The arc voltage rise value increases accordingly, increasing the current limiting effect.

〔Example〕

An embodiment of the present invention will be described below with reference to FIGS. 1 to 3.

"ON" and "OFF" operations are performed using the operating handle 3 protruding from the mold cover 2. By moving the handle to the power supply side, the two-bar link of the opening/closing mechanism section 4 having the toggle link *[ works, and the opening/closing mechanism An interlocking shaft 7, which is located at one end of the section 4 and rotates the three-pole movable contact block 9, rotates.The counterclockwise rotation of the interlocking shaft 7 causes the movable contact block 9 to rotate.
The entire unit moves around the bottle 16 as the center of rotation, and as a result, the movable contact 10 located at one end of the movable contact base moves to the current-limiting contact 1] position where it comes into contact with the movable contact 10.

It is arranged at the lower part of the opening/closing mechanism section in a direction opposite to the current limiting contact base 9 having the current limiting contact 11 at one end. The center of rotation of the current-limiting contact base 12 is held by a pin 17, and the pin 17 is provided with a return spring 13 that biases the current-limiting contact base 12 clockwise. This return spring 13 has one end attached to the mold case 1.
II! ! With respect to the bin 17, which is the center of rotation, on the side where the current limiting contact 11 of the current limiting contact base 12 whose end is placed first,
It engages with the current limiting contact base 12a extending on the opposite side. A flexible copper stranded wire 14 is connected to one end of this current-limiting contact block 12a, and the other end is a terminal block section 15a extending from the terminal block 15.
connected to one end of the This terminal block portion 15a is located at the power terminal 18 via the lower part of the bin 17, which is the center of rotation of the current limit contact block 11, in a positional relationship opposite to the current limit contact block 12. The contact pressure between the movable contact 10 and the current limiting contact 11 is
It is supplied by a contact spring 8 which is coaxial with the pin 16 which is the center of rotation of the movable contact base 9. In addition, for overcurrent detection, an oil dashbot relay structure 5 is provided, and the movable iron piece 19 attracted by the rising of the plunger causes the mechanism to trip.

Now, if a large current flows into the circuit breaker due to a short-circuit accident, the current-limiting contact block will rotate between the R terminal block section 150 and the current-limiting contact block section 12a, which are provided opposite each other as explained above. Current-limiting contact base 12b of the contact portion located on the opposite side of the central bottle
An electromagnetic repulsive force is generated due to the flowing short-circuit current at the 2tll point between the contact point and the movable contact base 9. As a result, the current-limiting contact base 12 is separated from the bin 17, which is the center of rotation, counterclockwise at high speed as a couple. This state is shown in FIG.

When the interruption is completed, the return spring 1 provided on the current-limiting contact block 12
3 returns to the original position.

According to this embodiment, the opening speed of the movable contact base 9 can be made three times or more that of the conventional one, and furthermore, since no time delay occurs, the station current effect can be improved.

Moreover, a highly reliable current limiting mechanism that can be mass-produced can be provided without increasing the number of parts.

Other embodiments will be described from FIG. 4 onwards. In Figure 4,
In order to further increase the opening speed of the current limiting contact 11, the distance between parallel conductors with different current directions for performing the m1 repulsion operation is increased, and the additional conductor 19 is the one. However, since it is not possible to open the contacts simply by making them longer, the structure is such that they are bent in the middle.

Other embodiments will be explained with reference to FIGS. 5 to 7. In FIG. 6, one end surface portion 12a'' of the current-limiting contact block 12 is partially inserted into the opposing hole 20 of the terminal block 15. In this embodiment, the electromagnetic repulsion current limiting structure is operated in which the couple acts only when a large current flows, such as when interrupting, by keeping the contact jump at intermediate current low.
Even in the case of a short circuit, in a short circuit region with a small current, the repulsion level due to current concentration in the conventional movable contact 10 and current limiting contact 11 portion can be sufficient to interrupt the short circuit. In this region, the couple effect of electromagnetic repulsion is small, and when the current-limiting contact block is slightly moved when the current is large, the repulsion force is increased by slightly lifting it from the hole 20 of the terminal block, and the above-mentioned couple repulsion is created. That is.

In the case shown in Figs. 8 to 10, the direction of current flow in a part of the terminal block 15'1 is different from that of a part of the current-limiting contact block 12b, so the electromagnetic force generated in the form of a couple is generated. A force is created that acts in the direction that prevents the repulsive force. In order to eliminate this force, a magnetic absorption plate is placed on the terminal block 15 to absorb the magnetic force that does not have the opposite effect. In addition, since the current limiting contact block sinks into most of the terminal block 16, the effect of the magnetic absorption plate 22 can be reversed to act as a magnetic holding force in a repulsive state when the contact block is moved. As shown in Fig. 10, when one end of the current-limiting contact block is located higher than the hole 21 of the terminal block and the hole 22 of the magnetic absorption plate, the short-circuit current that is already flowing will cause the current-limiting contact block to reach the terminal. A magnetic repulsion force is generated by the current flowing through the table 15. As a result, the repulsive force of the current-limiting contact block acts as an electromagnetic holding force against the force that attempts to return, producing an effect as a magnetic locking effect.

According to the above embodiment, the following effects can be obtained.

1. M magnetic repulsion current limiting without time delay can be performed in the event of a short circuit, and the opening speed of the contact block can be increased to 318 or higher than the conventional one.

2. In order to increase the opening speed of the contact block, the interval between some contact blocks of a terminal block having a couple repulsion structure can be made extremely small.

Because of item 3.2, by connecting one end with a flexible copper stranded wire, the temperature rise can be further reduced without interfering with the action during repulsion.

4. The number of parts can be realized without increasing compared to conventional products, and it is effective in terms of mass production (particularly in terms of price).

5. With a small number of parts and no contact springs or flexible steel strands placed in the arc-extinguishing chamber, a highly reliable current-limiting mechanism is created that eliminates the adhesion of molten material due to abrasion when shutting off. can be provided.

Next, further improvement plans for the above-mentioned embodiment are shown in FIGS. 11 to 20.
The diagram will be explained. This embodiment employs an electromagnetic repulsion current limiting mechanism as described above, and takes into consideration in particular the aspect of securing the cutoff distance for the energization switching and cutoff performance for the DC power source.

In addition, in the contact part with a current-limiting repulsion structure, we have taken into consideration the miniaturization and ensuring the breaking distance, especially when switching on and off the current, and the switching mechanism part that is effective in terms of AC performance. This is what we provide.

Furthermore, the present invention is designed to improve the current limiting and breaking performance, and the electromagnetically repulsed contact block is held in the repelling position until the complete breaking is completed.

In addition, by encasing the current-limiting closing/closing mechanism part in an insulating molded case to create a double insulation structure, damage caused by arcing and adhesion of molten substances that occur when shutting off are eliminated, and the side part of the switchgear is highly reliable. This is what we provide.

In other words, in this embodiment, the contact block, which operates by electromagnetic repulsion, is moved to ensure the breaking distance when the handle is operated to open/close, and the opening/closing operation is performed in conjunction with the repulsion when a large current such as a short circuit current flows. It is also designed to perform the movement of a repulsion contact base.

In addition, by interlocking the electromagnetic repulsion contact block provided for each phase with each pole interval, it is possible to secure the disconnection distance for DC power supplies and to provide a three-phase simultaneous repulsion mechanism for AC power supplies, improving current limiting performance. It was planned.

According to this, the movable contact bases provided in various
The three phases are integrated into one structure, and when electromagnetic repulsion occurs, the contact block is operated by the total sum of the electromagnetic forces generated by the various currents. In addition, in order to ensure a large disconnection distance between the movable contact and the current-limiting contact for opening of the DC power supply, the mechanical part 4
engages the movable frame 22 with the three-phase interlocking shaft,
Mechanical part 1fflFi! As a result of the operation, the repulsion contacts of the three phases also rotate counterclockwise around the pin 17 at the same time. As a result, the cutoff distance can be maintained in the same size as when electromagnetic repulsion is performed using the open-pole BOFF.

Hereinafter, this improvement plan will be explained first with reference to FIGS. 11 to 15.

The "ON" and "OF" operations are performed using the operating handle 3 that protrudes from the mold cover 2.
By moving to the I side, the two-bar link of the opening/closing mechanism section 4 having a toggle link mechanism works, and the interlocking shaft 7, which is located at one end of the opening/closing mechanism section 4 and rotates the movable contact base 9 for three poles, rotates. do. Due to this rotation, the movable frame 22 crimped to the interlocking shaft 7 rotates counterclockwise around the interlocking shaft 7.

As a result, the movable contact base 90 is attached to one end of the movable frame 22.
It has a pin 16 that is the center of rotation, and this pin 16 shares a contact spring 8 that controls contact pressure.

The movable contact 10 at one end of the movable contact base 9 moves by the movement of the interlocking shaft 7 to the position of the current-limiting contact 11 in which it comes into contact. They are located at the lower part of the mechanism section 4 in such a position that they face each other in opposite directions. The current-limiting contact base 12 has its center of rotation located at the lower part of the mechanism portion 4 and extends to the opposite side of the center of rotation of the contact 11. One end thereof is spotted by a flexible copper strand wire 4. The other end of the flexible copper stranded wire 14 extends from the terminal block 15, and is spotted and connected to one end facing the previous current-limiting contact block 12 so that the current direction is opposite. The movable contact base 12 has two insulating shafts 1 passing through each type.
7. On the 1st, the two locations are joined and the three phases are rotated around the bin 17 as one unit.

In addition, the movable frame 22 portion, which is caulked to the interlocking shaft 7 in the opening/closing mechanism section 4 that opens and closes "ON" and "OFF", has a metal fitting 25 that shares the pin 16, which is the center of rotation of the movable contact block, and the movable frame The rotation of 22 moves in the same manner as the rotation of interlocking shaft 7. The other end of the metal fitting 25 is engaged with an insulating shaft 18 that connects the contact base 12 in three-phase connection with each other in repulsive motion. Therefore, due to the clockwise rotation of the movable frame 22, the insulating shaft 18
is lifted, and the three-phase current-limiting contact base 12 rotates counterclockwise around the insulating shaft 17 that is the center of rotation. As a result, the current-limiting contact block during the opening operation is moved to almost the same position as during the repulsion, and a breaking distance is secured.

The return force is returned to the three phases at the same time by a return spring 13 provided at the center pole. As the movable frame 22 rotates counterclockwise at the same time as the "ON operation is OFF" (opening) operation, the current limiting contact moves upward and comes into contact with the movable contact 9.

Other embodiments will be described.

FIGS. 16 and 17 show that the three-phase interlocking shaft is constructed by an integrally formed insulating mold hole, and the protruding convex portion 7 of the interlocking shaft 7 is shown in FIG.
0 The integrally constructed contact block is rotated by the rotational force of the 0 part.
In this structure, each of the electromagnetic rings and generator components operates independently in the event of a short circuit, and the three phases are interlocked only during "ON" and "OFF" switching.

FIG. 18, FIG. 19, and FIG. 20 will be explained. This embodiment includes opposing parts of a current-limiting contact block 12 and a terminal block 15 that rotate electromagnetically, and a flexible copper stranded wire 14 that connects them.
A return spring 27 for biasing the return force of the current-limiting contact block 12 is inserted into another insulating molded product, which is inserted from the lower part of the molded case 1 as an assembled product and fixed. At this time, the return spring 27 engaged with the current limiting contact block 12
A convex portion 23a is provided at one end of the insulating cover to stop the end of the return spring 27 so that the spring 27 can be held independently on the insulating cover 23.

According to the above embodiment, the following effects can be obtained.

1. When a large current flows during a short circuit, the three phases are repelled at the same time, so the electromagnetic repulsion works as a total sum of the three phases, and the interruption is completed by the lowest passing current phase with less passing current. It is possible to block each phase individually, producing a large current-limiting and blocking effect.

2. ``ON''``OFF'' rtI closed t = By making the current-limiting contact block moveable, it is possible to secure a large breaking distance even with a current-limiting circuit breaker. In particular, performance in direct current interruption can be improved.

According to Section 3.2, the performance can be improved in terms of re-ignition without the phenomenon of the head of the movable and current-limiting contact block falling down after the mechanical part operates at the time of interruption.

4. Electromagnetic repulsion current limiting mechanism (especially return spring, flexible copper stranded wire)
etc. Il! By having a structure covered with positive insulating material and separating it from the arc extinguishing chamber of the main body, it is possible to provide a highly reliable current limiting circuit breaker that is free from damage caused by arcing and adhesion of molten material during interruption.

〔Effect of the invention〕

As is clear from the above description, according to the present invention, it is possible to improve the opening speed of the contact block during disconnection, to suppress the temperature rise of the contact portion to a low level, and to obtain a circuit breaker that can improve reliability. be able to.

[Brief explanation of drawings]

Fig. 1 is a cutaway front view showing one embodiment of the present invention in the ON state, Fig. 2 is a front view of main parts in the OFF state, and Fig. 3 is a front view of main parts in the OFF state.
The figure is a front view of the main part showing the electromagnetic repulsion state at the time of short circuit, No. 41!
I (A) is a schematic front view showing another embodiment, FIG. 4 (B
) is a schematic front view showing the same operating state, FIGS. 5, 6, and 7 are views showing other embodiments of the present invention, FIG. 5 is a front view of the terminal block, and FIG. A front view of the main part, Fig. 7 is a front view of the main part showing the operating state, Fig. 8, and Fig. 91! FIG. 10 is a diagram showing still another embodiment of the present invention, FIG. 8 is a plan view of the terminal block, FIG. 9 is a front view of the main part, and FIG. 10 is a main part showing the operating state. A front view, FIG. 11 is a cutaway front view in the ON state showing still another embodiment of the present invention, FIG. 12 is a front view of main parts, FIG. 13 is a perspective view of the current limiting contact block, and FIG. 14 is an operation. FIG. 15 is a perspective view showing the relationship between the current-limiting contact block and the movable contact block, FIG. 16 and FIG. 17 are views showing still other embodiments, and FIG. is a front view of main parts, 1st
7 is a perspective view of the same, FIG. 18, FIG. 19, and FIG. 20 are views showing still other embodiments of the present invention, FIG. 18 is a front view of the main part, and FIG. 19 is a part thereof. FIG. 20 is an enlarged front view showing the main part, and FIG. 20 is a Ti view showing the main part enlarged. 9: Movable contact block, 12: Current-limiting contact block, 14: Possible In /
IJ wire, 15; Terminal block ~ Dimension diagram (A) ＼ Figure 12 Figure 3 Figure 18 Intercept

Claims (1)

[Scope of Claims] 1. In a device having an electromagnetic repulsion current limiting mechanism in which the movable contact block and the current limiting contact block have mutually flowing current directions in opposite directions, a portion of the current limiting contact block facing the movable contact block; The current-limiting contact block has another part facing the terminal block at a part opposite to the center of rotation of the current-limiting contact block, and the current-limiting contact block has a couple of electromagnetic repulsion forces generated on both sides of the center of rotation. The circuit breaker is characterized in that the end of the other opposing portion of the current-limiting contact block and the end of the terminal block are connected by a flexible conducting wire. 2. In the device having an electromagnetic repulsion current limiting mechanism in which a movable contact block and a current limiting contact block are arranged to face each other so that the directions of current flowing are opposite to each other, the electromagnetic repulsive force causes the current limiting contact block to simultaneously move in multiple phases. A circuit breaker characterized in that the circuit breaker is equipped with interlocking means for interlocking a plurality of poles of the current-limiting contact block so that the current-limiting contact block is actuated simultaneously for a plurality of phases by the opening operation of the opening/closing mechanism part. .