JPS62170124A - Circuit breaker - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention provides a method for controlling first and second movable contacts that are normally in a contact state to generate a voltage between the first and second movable contacts based on a fault current. The present invention relates to a circuit breaker configured to separate from each other using electromagnetic repulsion.

[Technical background of the invention and its problems 1 A circuit breaker is basically configured to open the main circuit by displacing the movable contact from the closing position to the opening position using a tripping device when an overcurrent is detected. .

However, in recent years, with the aim of improving the breaking performance, in addition to the first movable contact displaced by the tripping device, a second movable contact that is energized so as to be in constant contact with the first movable contact in the closed circuit position has been developed. 2 movable contacts are provided, and the electromagnetic repulsion force generated when the fault current flows through the first and second movable contacts in mutually opposite directions is used to connect the first movable contact and the second movable contact. In addition to this, there is a device in which the
As shown in No. 31, a plunger-type relay comprising a coil and a plunger is provided near the first and second movable contacts, and when the plunger is displaced due to the fault current flowing through the coil, A configuration has been considered in which the fault current is limited by forcibly rotating the first movable contact in a direction away from the second movable contact. The specific structure of this is as shown in FIGS. 4 and 5. Here, first, in FIG. 4, 1 is an operating handle provided on the case 2, 3 is a first movable contact whose one end is pivotally supported on a support plate 4 by a shaft 5; The child 3 is biased counterclockwise in the figure by a tension coil spring 6 stretched between its intermediate portion and the support plate 4. 7 is a well-known toggle mechanism provided between the operating handle 1 and the first movable contact 3; 8 is a tripping device; this tripping device 8 is activated when an overcurrent in the main circuit is detected; By releasing the catch 10 from the latch 9, the first movable contact 3 is allowed to rotate clockwise from the "open" position shown in the figure to an open position (not shown). . A second movable contact 11 is provided below and along the first movable contact 3, one end of which is pivotally supported on the support portion 12 by a shaft 13, and the other end of which is connected to the compression coil. The spring 14 always keeps this contact 11a
is biased so as to contact the contact point 3a of the first movable contactor 3, thereby closing the main circuit. A fixed conductor 15 constitutes a power supply terminal, and this and the second movable contact 11 are connected by a flexible conductor 16. 17 is a plunger type relay provided on three sides of the first movable contact 3;
This comprises a coil 13 and a plunger 20 provided in a container 19 so as to be movable up and down.The coil 18 has one end connected to the first movable contact 3 by a flexible conductor 21 and the other end connected to the first movable contact 3 by a flexible conductor 21. The plunger 20 is connected to a tripping device 8, and a lower portion of the plunger 20 passes through an intermediate portion of the first movable contact 3, and a protrusion 22 is formed at the lower end thereof.

Note that 23 is an arc extinguishing device for extinguishing the arc generated between the first and second movable contacts 3 and 11.

In this configuration, when a large fault current such as a short circuit current flows in the main circuit, the first and second movable contacts 3 and 1
1, since currents flowing in opposite directions flow, electromagnetic repulsion is generated between the first and second movable contacts 3 and 11. In addition, plunger type relay 1
7, the plunger 20 is pulled upward in the figure due to the fault current flowing through the coil 18. Therefore, prior to the opening operation of the first movable contact 3 based on the operation of the tripping device 8, the first movable contact 3 is attached to the tension coil spring 6 due to the electromagnetic repulsion as shown in FIG. At the same time, the second movable contact 11 rotates counterclockwise around the shaft 13 by 1° counterclockwise against the biasing force of the compression coil spring 14. rotate to
On the other hand, the plunger 20 in the plunger type relay 17
Due to the movement of the protrusion 22 at the lower end of the plunger 20,
hits the first movable contact 3 and forcibly rotates it in the clockwise direction. As the first and second movable contacts 3, 11 rotate away from each other, an arc is generated between the first and second movable contacts 3, 11, and a large current is generated. Current limited, arc extinguishing device 23
As the arc is extinguished, the first movable contact 3 is displaced to the open position by the subsequent operation of the tripping device 8, and the main circuit is completely opened.

However, in the case of such a configuration, the first movable contact 3 rotates in a direction away from the second movable contact 11 due to the electromagnetic repulsion force and the operation of the plunger type relay 17; The contactor 11 rotates in a direction away from the first movable contactor 3 only by electromagnetic repulsion. Therefore, as the distance between the first and second movable contacts 3 and 11 increases, the electromagnetic repulsion force decreases. 3, and in this case, currents flow in opposite directions to the second movable contact 11 and the fixed conductor 15, so that the second movable contact 11 and the fixed conductor 15 Electromagnetic repulsion is also generated between the conductor 15 and the second movable contact 11 tends to rotate in the direction closer to the first movable contact 3 due to this, thus preventing interruption when a fault current occurs. The drawback was that the performance could not be improved even further.

[Object of the Invention] The present invention has been made in view of the above circumstances, and its purpose is to provide first and second movable contacts that rotate in directions away from each other due to electromagnetic repulsion due to fault current. It is an object of the present invention to provide a circuit breaker which can be held in a separated position until a circuit is completely interrupted, and which can improve interrupting performance when a fault current occurs.

[Summary of the Invention] The present invention is directed to moving a first movable contact and a second movable contact away from each other by an electromagnetic repulsion force generated between the first and second movable contacts based on a fault current. In a rotatable circuit breaker, a plunger type relay comprising a coil and a plunger is provided near the first and second movable contacts, whereby a fault current flows through the coil of the plunger type relay. Due to the displacement of the plunger based on this, the first movable contact is rotated in a direction away from the second movable contact, and the second movable contact is rotated in a direction away from the first movable contact. It is characterized by the fact that it is

[Embodiment of the Invention] An embodiment of the present invention will be described below with reference to FIGS. 1 to 3. However, the same parts as in the conventional (&) are given the same reference numerals and detailed explanations will be omitted.

That is, in FIG. 1, 1 is an operating handle, 2 is a case, 7 is a toggle mechanism, 8 is a tripping device, 9 is a latch,
10 is a catch, 15 is a fixed conductor, and 23 is an arc extinguisher.

Now, 24 is a first movable contact whose one end is pivotally supported by a support plate 25 by a support plate 25, and this is supported by a tension coil spring 27 stretched between an intermediate part of this and the support plate 25. It is biased counterclockwise in the figure. 28 is a second movable contact provided below and along the first movable contact 24, whose middle part is pivoted to the support part 29 by a shaft 30, and whose left end in the figure is compressed. The coil spring 31 normally biases the contact 28a of the coil spring 31 so that it contacts the contact 24a of the first movable contact 24, thereby closing the main circuit. The intermediate portion of the second movable contact 28 and the fixed conductor 15 are connected via a flexible conductor 32. 33
is a plunger-type relay installed near the first and second movable contacts 24 and 28, in this case above the movable contact 24 of box 1, which is installed on the coil 34 and container 35 so as to be movable up and down. A plunger 36 is provided. Among them, the coil 34 has one end connected to the first movable contact 24 via a flexible conductor 37 and the other end connected to the tripping device 8 . Further, the plunger 36 has a lower portion located at the first movable contact 24 and a left side of the shaft 26 and the second movable contact 24.
8, which passes through the right side of the shaft 30, and has a first protrusion 38 formed below the first movable contact 24, and a first protrusion 38 formed below the second movable contact 28. Two protrusions 39 are formed. In such a plunger type relay 33, when the plunger 36 is displaced upward in the figure based on the fault current flowing through the coil 34,
As shown in FIG. 2, the first projection 38 hits the first movable contact 24 and rotates it clockwise, and the second projection 39 hits the second movable contact 28 and rotates it clockwise. The plunger 3 is rotated counterclockwise and is based on the fact that a fault current flows through the coil 34.
6, the first movable contact 24 is rotated in the direction away from the second movable contact 28, and the second movable contact 28 is rotated in the direction away from the first movable contact 24. It is designed to let you do so.

In the above configuration, when a large fault current such as a short circuit current flows in the main circuit, the first and second movable contacts 24.2
8, these first and second movable contacts 24 are caused to flow in opposite directions as shown by arrows A in FIG.
．． On the other hand, in the plunger type relay 33, the plunger 36 is displaced in the direction of arrow B in FIG. The protrusion 38 hits the first movable contact 24 and rotates the first movable contact 24 in a direction away from the second movable contact 28, and the second protrusion 39 contacts the second movable contact 24. child 28
This causes the second movable contact 28 to rotate in a direction away from the first movable contact 24. For this reason, the first
The movable contact 24 rotates in a direction away from the second movable contact 28 against the spring force of the tension coil spring 27, while the second movable contact 28 resists the spring force of the compression coil spring 31. It rotates in the direction away from the first movable contact 24 against the opposite. Even if the first and second movable contacts 24, 28 are separated by this separation operation, these contacts 24a,
The fault current continues to flow while being limited by the arc that occurs between 28a and 28a (see Figure 2). In this case, while the fault current is flowing through the arc, the plunger 36 of the plunger type relay 33 is in a state displaced in the direction of arrow B.
The first and second movable contacts 2 are connected by the projections 38 and 39 of the
4.28 are held in their respective separated positions. Thereafter, when the tripping device 8 is activated and the first movable contact 24 is displaced to the open position together with the support plate 25 by the toggle mechanism 7 as shown in FIG. 3, the arc voltage increases rapidly. Fault current is completely cut off. As a result, the plunger 36 in the plunger type relay 33 is displaced in the direction opposite to the arrow B and returns to its original position, and the first movable contact 24 is moved to the second position by the biasing force of the tension coil spring 27.
The second movable contact 28 rotates toward the first movable contact 24 due to the biasing force of the compression coil spring 31. In this case, even if the first and second movable contacts 24 and 28 rotate in the direction closer to each other, the first movable contact 24 and the support plate 25 are displaced to the open position. , these first and second movable contacts 24, 28 do not come into contact with each other, and therefore the main circuit is not closed.

In this way, according to this embodiment, without waiting for the operation of the tripping device 8, the first and second
The first and second movable contacts 24,28 are rotated in the direction away from each other, and the first and second movable contacts 24,28 are also rotated in the direction away from each other by the plunger type relay 33. Only the first movable contact 3 is connected to the second movable contact 11 by the plunger type relay 17.
Unlike the conventional configuration in which the second movable contact 28 is forcibly rotated in a direction away from the second movable contact 28, the compression coil spring 31 prevents the second movable contact 28 from returning toward the first movable contact 24. In addition, even if electromagnetic repulsion occurs between the second movable contact 28 and the fixed conductor 15, the second movable contact 28 will not be close to the first movable contact 24. This prevents the tendency to rotate in the direction of
Therefore, the first and second movable contacts 24, 28 can be held in the separated position until the main circuit is completely interrupted, thereby improving the interrupting performance.

In the two-legged embodiment, the plunger 36 of the plunger type relay 33 connects the first and second movable contacts 24 and 28.
By pulling up these first and second movable contacts 24
．． 28 in the direction away from each other.
Instead of this, for example, the first and second movable contacts may be rotated in the direction away from each other by pushing down the first and second movable contacts with a plunger of a plunger type relay. However, the present invention can be implemented with appropriate modifications within the scope of the invention.

[Effects of the Invention] As is clear from the above description, the present invention allows the main circuit to completely interrupt the first and second movable contacts that rotate in directions away from each other due to electromagnetic repulsion caused by fault current. This provides an excellent effect in that it can be held in the separated position until it is interrupted, thereby improving the interrupting performance when a fault current occurs.

[Brief explanation of drawings]

1 to 3 show one embodiment of the present invention, FIG. 1 is a longitudinal sectional view of the whole, and FIG. 2 is an enlarged view of the main part showing the separation operation state of the first and second movable contacts. FIG. 3 is an enlarged vertical cross-sectional view showing a state in which the first movable contact is displaced to an open position. 4 and 5 show the conventional configuration, FIG. 4 is a diagram equivalent to FIG. 1, and FIG. 5 is a diagram equivalent to FIG. 1 showing the separation operation state of the first and second movable contacts. be. In the drawing, 8 is a tripping device, 24 is a first movable contact, 2
6 is a shaft, 28 is a second movable contact, 30 is a shaft, 33 is a plunger type relay, 34 is a coil, 36 is a plunger,
38 is a first protrusion, and 39 is a second protrusion. Agent Patent Attorney Nori Ken Yudo Hiroshi Mitsumata 7 Figure 2 Figure 3 Figure 4 Figure 5

Claims (1)

[Claims] 1. A first movable contact that is rotatably supported and is displaced from a closed circuit position to an open circuit position by a tripping device when an overcurrent is detected; and the first movable contact that is rotatably supported and is in a closed circuit position. and a second movable contact that is biased so as to be in constant contact with the contact, and the electromagnetic repulsion generated between the first and second movable contacts based on the fault current causes the first movable contact to and a second movable contact are rotated in directions away from each other, and a coil and a plunger are provided in the vicinity of the first and second movable contacts, and a fault current is applied to the coil. The displacement of the plunger based on the flow causes the first movable contact to rotate in a direction away from the second movable contact, and also rotates the second movable contact in a direction to move away from the first movable contact. A circuit breaker characterized by being equipped with a plunger-type relay that operates the circuit.