JP6733369B2 - Gas circuit breaker - Google Patents

Description

The present invention relates to a magnetic puffer type gas circuit breaker with magnetic drive.

The gas circuit breaker (GCB) is used as one component of a gas insulated switchgear (GIS), and is incorporated in a tank that stores an insulating gas such as SF ₆ gas. As one of the gas circuit breakers, for example, as disclosed in Patent Document 1, there is a magnetic drive combined thermal puffer type gas circuit breaker.

The magnetic puffer type gas circuit breaker combined with magnetic drive is a magnetic drive action in which the arc is orbitally driven in the gas atmosphere by the magnetic force generated in the drive coil to blow the gas relative to the arc, and the gas accumulated by the arc heat is stored. It is configured so as to obtain a thermal puffer action of spraying on the arc at the time of discharge of. Further, the arc extinguishing action of the both enables more effective current interruption.

JP-A-6-290688

By the way, in the gas circuit breaker, it is desired to improve the current breaking performance. As one of the countermeasures, it is conceivable to further increase the insulation between both the contactors in the initial stage of the current interruption when the movable contactor starts to separate from the fixed contactor. In other words, if the insulation between both terminals is increased at the initial stage of current interruption, arc generation (in this case, arc reoccurrence after extinguishing the current zero point of the arc generated by the start of current interruption) can be suppressed from the initial stage. The current is cut off more reliably.

The present invention has been made to solve the above problems, and an object thereof is to suppress the occurrence of an arc at the initial stage of current interruption and to improve the interruption performance by using a magnetic puffer type thermal puffer type gas. To provide a circuit breaker.

A gas circuit breaker for solving the above-mentioned problem moves an arc in a gas by a magnetic force generated by excitation of a drive coil, in contrast to an arc generated when a movable contact is separated from a fixed contact in a process of interrupting a current. Both the magnetic drive action of blowing a gas relative to the arc and the thermal puffer action of accumulating the gas in the heat puffer chamber by heating the gas by the arc and blowing the accumulated gas to the arc. A gas circuit breaker that also uses the arc extinguishing action of, wherein gas is supplied to an arc generation point generated between the fixed contact and the movable contact by the separation operation of the movable contact, and the arc generation point Further, a mechanical puffer mechanism for increasing the gas density of the above compared to other places is further provided.

According to this configuration, the mechanical puffer mechanism that performs the gas supply operation by the separation operation of the movable contact is provided, and the gas is supplied to the arc generation point generated between the fixed contact and the movable contact. The gas density at the arc generation location is made higher than at other locations. In other words, due to the high-density gas atmosphere between the fixed contact and the movable contact, the arc is less likely to be generated (the arc is regenerated after extinguishing the current zero point), and the breaking performance can be expected to be improved. ..

Further, in the above gas circuit breaker, the puffer mechanism is provided in a movable contactor-side unit having the movable contactor, and the inner path of the movable contactor in a tubular shape and a mechanical puffer chamber in the puffer mechanism. It is preferable that the gas is supplied to the location where the arc is generated by communicating with.

According to this configuration, since the gas is supplied to the arc generation point between the fixed contact and the movable contact using the inner passage of the cylindrical movable contact, it is possible to directly supply the arc to the arc generation point. It is possible to suitably supply gas. Further, by using the inner space of the movable contactor, it is possible to expect space saving and simplification of the structure as compared with the case where a passage corresponding to the inner passage is separately provided.

In the gas circuit breaker, the opening on the puffer mechanism side of the inner passage of the movable contact is located outside the puffer mechanism in correspondence with the position where the thermal puffer action occurs in the process of the movable contact separating operation. Preferably, it is arranged so that part of the gas release due to the thermal puffer action takes place using the inner passage.

According to this configuration, when the movable contactor comes close to the position where the thermal puffer action occurs during the separating operation, the opening on the puffer mechanism side in the inner passage of the movable contactor is arranged outside the puffer mechanism. That is, a part of the gas released by the thermal puffer action is performed through the inner passage of the movable contactor, and it is possible to suppress the excessive increase of the gas pressure by the thermal puffer.

In the gas circuit breaker, the movable contactor-side unit having the movable contactor is provided with the thermal puffer chamber, the drive coil, and the puffer mechanism, and the puffer mechanism is used to move to the arc generation location. It is preferable that an introduction passage for supplying gas is provided separately from the thermal puffer chamber.

According to this configuration, in the movable contact unit, the introduction passage for supplying the gas by the puffer mechanism is provided at the arc generation position separately from the thermal puffer chamber, so that the introduction passages corresponding to the function of the puffer mechanism are individually provided. Can be set to.

In the gas circuit breaker, the fixed contact has first and second fixed contacts, the movable contact has first and second movable contacts, and the first fixed contact and The first movable contactor is located radially outward, the second fixed contactor and the second movable contactor are located radially inward, respectively, and the first fixed contactor and the first movable contactor are separated from each other. Also, the second fixed contactor and the second movable contactor are separated from each other later to perform arc extinction between the second fixed contactor and the second movable contactor. The thermal puffer chamber, the drive coil, and the introduction passage are arranged between a first movable contactor fitted in the contactor and a second movable contactor fitted in the second fixed contactor. Is preferred.

According to this configuration, the thermal puffer chamber, the drive coil, and the introduction passage are arranged between the first movable contactor that is fitted inside the first fixed contactor and the second movable contactor that is fitted around the second fixed contactor. Therefore, it can be expected to have an efficient arrangement configuration.

According to the gas circuit breaker of the present invention, it is possible to suppress the generation of an arc at the initial stage of current interruption and improve the interruption performance.

Sectional drawing of the magnetic drive combined thermal puffer type gas circuit breaker of 1st Embodiment. (A) (b) is sectional drawing for demonstrating operation|movement of a gas circuit breaker. Sectional drawing of the magnetic puffing type thermal circuit breaker of 2nd Embodiment. (A) (b) is sectional drawing for demonstrating operation|movement of a gas circuit breaker.

(First embodiment)
The first embodiment of the gas circuit breaker will be described below.
The gas circuit breaker G1 of the present embodiment shown in FIG. 1 is a magnetic drive combined thermal puffer type gas circuit breaker. The gas circuit breaker G1 is used as a component of a gas insulated switchgear (not shown), and is incorporated in a tank (not shown) that stores an insulating gas such as SF ₆ gas. That is, the gas circuit breaker G1 is arranged in an atmosphere of insulating gas.

The gas circuit breaker G1 includes a fixed contactor side unit 10 having a fixed contactor 11 and a movable contactor side unit 20 having a movable contactor 21. The fixed contactor 11 of the fixed contactor-side unit 10 and the movable contactor 21 of the movable contactor-side unit 20 are arranged coaxially so that the movable contactor 21 performs a contact/separation operation with respect to the fixed contactor 11. Is configured. Incidentally, the state on the left side of the center line of the gas circuit breaker G1 in FIG. 1 is the closed state (closed state) of the gas circuit breaker G1 and connects the electric path on the fixed contact 11 side and the electric path on the movable contact 21 side. It is in the state of having done. Further, the state on the right side of the center line of the gas circuit breaker G1 in FIG. 1 is the open state (blocking state) of the gas circuit breaker G1 and disconnects the electric path on the fixed contact 11 side and the electric path on the movable contact 21 side. It is in the state of having done.

In the fixed contactor side unit 10, the fixed contactor 11 is formed in a substantially cylindrical shape, and the substantially cylindrical coil support portion 12 is coaxially provided on the outer side of the fixed contactor 11 so that the base end portions thereof (see FIG. The upper end) is in a connected state. The coil support portion 12 is configured to have an axial length substantially equal to that of the fixed contactor 11. A drive coil 13 having a winding shape is attached to a tip portion (lower end portion in FIG. 1) of the coil support portion 12 so as to circulate around the center axis of the coil support portion 12 along a peripheral edge of the tip. An annular plate-shaped arc runner 14 is attached to the side of the drive coil 13 opposite to the coil support 12 (lower side in FIG. 1). The inner diameter of the arc runner 14 is slightly larger than the inner diameter of the fixed contactor 11, and the arc runner 14 and the fixed contactor 11 are separated by a predetermined distance in the axial direction.

Here, the fixed contactor 11 and the coil support portion 12 are integrally provided on the base portion 15 of the fixed contactor side unit 10, and these members and the arc runner 14 are made of a conductor. The arc runner 14 and one end of the drive coil 13 are electrically connected, and the other end of the drive coil 13 and the tip of the coil support portion 12 are electrically connected. That is, when an arc occurs between the movable contact 21 and the arc runner 14 when the movable contact 21 is retracted from the fixed contact 11, a current based on the arc causes the coil support 12 (fixed contact 11) to drive. The driving coil 13 is excited by flowing on a path including the coil 13 and the arc runner 14.

An insulating nozzle member 16 is attached to the base portion 15 so as to surround the fixed contact 11, the coil support portion 12, the drive coil 13, and the arc runner 14. The nozzle member 16 has a substantially cylindrical shape, and a base end portion (upper end portion in FIG. 1) is integrally connected to a peripheral portion of the base portion 15. The peripheral wall portion 16a of the nozzle member 16 extends in the axial direction sufficiently longer than the position where the arc runner 14 is provided. Further, the peripheral wall portion 16a of the nozzle member 16 is separated from the coil support portion 12, the drive coil 13, and the arc runner 14 with a predetermined distance in the radial direction.

A tip portion (lower end portion in FIG. 1) of the peripheral wall portion 16a of the nozzle member 16 is configured as a nozzle portion 16b having a shape that is folded back and extends obliquely toward the central axis direction. The tip portion of the nozzle portion 16b extends near the inner peripheral edge of the arc runner 14. The inner diameter of the tip portion of the nozzle portion 16b is set to be substantially equal to the inner diameter of the fixed contactor 11.

The substantially cylindrical space formed so as to be surrounded by the base portion 15, the peripheral wall portion 16a of the nozzle member 16, the nozzle portion 16b, the coil support portion 12, the drive coil 13, and the arc runner 14 is a heat puffer chamber (accumulation chamber). I am 17. Further, although the tip end portion of the nozzle portion 16b is extended to the vicinity of the arc runner 14, it is separated from the arc runner 14 by a predetermined distance in the axial direction. That is, the narrow opening formed between the tip of the nozzle portion 16 b and the arc runner 14 functions as an injection port 17 a for the gas accumulated in the thermal puffer chamber 17. As described above, the fixed contactor side unit 10 includes the thermal puffer portion P1 including the thermal puffer chamber 17.

In the movable contact side unit 20, the movable contact 21 is made of a conductor and has a substantially cylindrical shape. The movable contactor 21 is supported coaxially with the fixed contactor 11 with respect to the base portion 22 of the movable contactor side unit 20, and is supported so as to be movable in the axial direction with respect to the base portion 22 which is an immovable member. There is. The outer diameter of the movable contactor 21 is set to be substantially the same as the inner diameter of the fixed contactor 11, and the movable contactor 21 is configured to be insertable into the fixed contactor 11 by internal fitting. The movable contact 21 is adapted to perform a reciprocating linear motion (vertical movement in FIG. 1) along the central axis by a drive mechanism (not shown), that is, a contact/separation motion with respect to the fixed contact 11. The movable contact 21 is arranged at the most protruding position in the closed state (closed state) on the left side of FIG. 1, and is arranged at the most retracted position in the opened state (blocking state) on the right side of FIG. Further, the movable contactor 21 is brought into a state of being close to each inner edge portion when passing through the inner edge portion of the arc runner 14 or the inner edge portion of the nozzle portion 16b in the operation process thereof.

The inner portion of the cylindrical movable contactor 21 functions as an inner passage 21a through which gas flows. At the time of contact between the movable contactor 21 and the fixed contactor 11, the tip opening portion (upper end opening portion in FIG. 1) of the movable contactor 21, that is, one end of the inner passage 21a communicates with the inner space 18 of the fixed contactor 11. To do. A connection passage 21b, which communicates with the other end of the inner passage 21a and opens radially outward, is provided at the base end of the movable contact 21.

Further, while the fixed contactor side unit 10 is provided with the thermal puffer portion P1, the movable contactor side unit 20 is provided with the mechanical puffer portion P2. That is, a puffer mechanism 23 having a cylinder structure is incorporated in the base portion 22 of the movable contactor side unit 20 so as to perform a mechanical puffer operation. The puffer mechanism 23 is arranged on the opposite side of the fixed contactor side unit 10 in the base portion 22, and is provided so as to surround the movable contactor 21.

The puffer mechanism 23 includes a puffer case 24, a pressing plate 25, and a biasing spring 26. The puffer case 24 is fixed to the base portion 22 and has a hollow structure having a puffer chamber (mechanical puffer chamber) 27 inside. The puffer case 24 has a pair of insertion holes 24a and 24b, and the movable contactor 21 is inserted through the insertion holes 24a and 24b. The mechanical puffer chamber 27 in the puffer case 24 has an opening on the side of the movable contact 21 through which the mechanical puffer chamber 27 is inserted, that is, an annular closed space including the outer surface of the movable contact 21.

The pressing plate 25 is housed in the mechanical puffer chamber 27 so as to be movable in the same direction as the axial direction (movement direction) of the movable contact 21. In this case, the pressing plate 25 is provided so as to be movable in the axial direction of the movable contact 21 while maintaining the state where its main plane faces the axial direction of the movable contact 21 (the state parallel to the axis orthogonal direction). Has been. In addition, a locking portion 21c that locks with the pressing plate 25 when the movable contact 21 is moved toward the protruding side is provided at a portion of the movable contact 21 that is closer to the tip than the connection passage 21b. A biasing spring 26 is provided on the back side of the pressing plate 25 in the mechanical puffer chamber 27. In the range where the pressing plate 25 and the locking portion 21c of the movable contact 21 can be locked, the pressing plate 25 and the locking portion 21c of the movable contact 21 are locked by the urging force of the urging spring 26. Is being maintained.

Here, in the process of axially projecting/retracting the movable contactor 21, the movable contactor 21 is at the most protruding position in the closed state (closed state) of the gas circuit breaker G1 shown on the left in FIG. 11 is in a fitted state. In this state, the pressing plate 25 is pushed in by the engagement with the engagement portion 21c of the movable contact 21, and the biasing spring 26 is in the contracted state. Further, in this case, the capacity of the mechanical puffer chamber 27 on the front side of the pressing plate 25 (the side opposite to the side on which the biasing spring 26 is installed) is the maximum, and the connection passage 21b between the mechanical puffer chamber 27 and the movable contact 21 is formed. And are in communication.

Next, as shown in FIG. 2A, in a boundary state where the movable contact 21 is in contact with or away from the fixed contact 11, a state in which the movable contact 21 receives the urging force of the urging spring 26 and contacts the locking portion 21c. The pressing plate 25, which has been maintained, operates to reduce the volume of the mechanical puffer chamber 27 as the movable contact 21 retracts, and the volume becomes about half of the maximum. Also in this case, the mechanical puffer chamber 27 and the connection passage 21b are in communication with each other.

Next, as shown in FIG. 2B, in a state in which the tip of the movable contact 21 is located approximately in the middle between the tip of the fixed contact 11 and the tip of the nozzle portion 16b and is close to the arc runner 14, The pressing plate 25 comes into contact with the inner surface of the puffer case 24, and further movement is restricted, so that the locking of the movable contact 21 with the locking portion 21c is released. Further, in this state, the volume of the mechanical puffer chamber 27 is zero due to the pressing plate 25, and the opening of the connection passage 21b of the movable contact 21 is located outside the insertion hole 24b of the puffer case 24, that is, the gas-insulated switchgear is not shown. It is open to the tank space.

In the open state (blocking state) of the gas circuit breaker G1 shown on the right in FIG. 1, the movable contact 21 is in the rearmost retracted position and is sufficiently separated from the fixed contact 11, and in this case is sufficiently separated from the nozzle portion 16b. It is in a state. The pressing plate 25 and the locking portion 21c of the movable contact 21 are further separated from each other, and the volume of the mechanical puffer chamber 27 remains zero.

In the puffer case 24, a through hole 24c for reducing the back pressure applied to the pressing plate 25 is provided in a region on the back surface side of the pressing plate 25. Further, in the puffer case 24 on the front surface side of the pressing plate 25, a valve is opened when the insulating gas is introduced from the outside of the puffer case 24 into the inside (the mechanical puffer chamber 27), and vice versa. A valve 28 is provided. In other words, the check valve 28 operates (changes from FIG. 2B to FIG. 2A) so that the pressing plate 25 increases the volume of the mechanical puffer chamber 27 as the movable contact 21 projects. At that time, the valve itself opens to reduce the operation load of the pressing plate 25.

Next, the operation of the gas circuit breaker G1, particularly the breaking operation will be described.
In the closed state (closed state) of the gas circuit breaker G1 shown on the left side of FIG. 1, the tip of the movable contact 21 is fitted in the fixed contact 11, and the movable circuit and the electric path on the fixed contact 11 side are in contact with each other. The electric circuit on the child 21 side is in an electrically connected state.

In the process of moving the movable contactor 21 backward from the closed state of the gas circuit breaker G1 to the completely opened state (blocking state) shown in the right side of FIG. 1, first, the movable contactor 21 is slightly retracted. The pressing plate 25 of the puffer mechanism 23 pushes the biasing force of the biasing spring 26 until the tip of the movable contactor 21 with respect to the fixed contactor 11 is near the connecting/separating boundary position shown in FIG. By receiving the force, the volume of the mechanical puffer chamber 27 is reduced as the movable contact 21 moves backward. Then, the insulating gas existing in the mechanical puffer chamber 27 is discharged to the inner space 18 of the fixed contact 11 via the connection passage 21b and the inner passage 21a as shown by an arrow a in FIG. The density of the insulating gas around the tip of the fixed contact 11 and its surroundings, which may occur, is increased in advance.

As a result, a high-density insulating gas atmosphere is formed between the tip of the fixed contact 11 and the tip of the movable contact 21, so that the movable contact 21 and the movable contact 21 can move in the backward movement process. It becomes more difficult for the arc A to be generated between the contact 21 and each tip (regeneration after extinguishing the current zero point of the arc A). The gas releasing operation by the puffer mechanism 23 continues while the connection passage 21b is kept connected to the mechanical puffer chamber 27 even if the movable contact 21 further moves backward than in FIG. 2A.

Next, when an arc A occurs between the tip of the fixed contact 11 and the tip of the movable contact 21, when the movable contact 21 further retracts and reaches the position near the position of FIG. The arc A continuously generated between the tips of the contactor 11 and the movable contactor 21 moves from the fixed contactor 11 to the arc runner 14 side. Then, the current based on the arc A flows on the path including the coil support portion 12, the drive coil 13, and the arc runner 14, and the drive coil 13 is in the excited state.

As a result, the arc A generated between the tip of the movable contactor 21 and the inner edge of the arc runner 14 is orbitally driven along the tip and the inner edge as indicated by arrow b in FIG. 2B. The arc A moves in the gas at high speed. In other words, an arc extinguishing action corresponding to blowing gas relative to the arc A occurs (magnetic drive action). Incidentally, since the arc A circulates along the tip of the movable contact 21 having a cylindrical shape, the wear of the tip of the movable contact 21 due to the arc A is not local but average.

Since the arc A between the tip of the movable contactor 21 and the inner edge of the arc runner 14 is in the vicinity of the nozzle portion 16b, which is the opening of the heat puffer chamber 17, the arc A is driven to rotate so that the heat puffer The temperature of the gas in the chamber 17 rises, and the volume expansion associated with the temperature rise of the gas causes the pressure of the gas to be accumulated in the thermal puffer chamber 17.

At the same time, the insulating gas around the fixed contact 11 and the nozzle portion 16b vigorously flows through the inner passage 21a and the connection passage 21b of the movable contact 21 as shown by the arrow c in FIG. 2B. It is discharged into the tank of the insulated switchgear (the space around the gas circuit breaker G1 in FIGS. 1 and 2). That is, the insulating gas is blown to the arc A between the tip of the movable contactor 21 and the inner edge of the arc runner 14, and the arc extinguishing action is thereby generated (thermal puffer action). In this case, it is possible to prevent the gas pressure in the heat puffer chamber 17 and the like from rising excessively.

Further, when the movable contactor 21 is further retracted, the tip of the movable contactor 21 is separated from the inner edge of the nozzle portion 16b until the movable contactor 21 reaches the completely open state (blocking state) shown in the right side of FIG. The insulating gas accumulated in the thermal puffer chamber 17 or the like as indicated by the arrow d is vigorously discharged from the gap between the tip of the movable contact 21 and the inner edge of the nozzle 16b. That is, even in this case, the insulating gas is blown to the arc A continuously generated between the tip of the movable contactor 21 and the inner edge of the arc runner 14, so that the arc extinguishing action is also generated. (Heat puffer function).

As described above, in the shutoff operation of the gas circuit breaker G1 according to the present embodiment, first, the mechanical puffer portion P2 operates to direct the gas toward the arc A generation point between the fixed contact 11 and the movable contact 21. Since the gas atmosphere is supplied and the gas atmosphere has a high density, the initial generation of the arc A (regeneration after extinguishing the current zero point of the arc A) is less likely to occur. Further, even when the arc A is generated, the magnetic drive by the drive coil 13 and the operation of the thermal puffer portion P1 are performed thereafter to perform more reliable arc extinguishment, so that improvement of the breaking performance can be expected. There is.

Next, the characteristic effects of this embodiment will be described.
(1) A mechanical puffer mechanism 23 that performs a gas supply operation by the separating operation of the movable contact 21 is provided, and gas is generated at a position where an arc A generated between the fixed contact 11 and the movable contact 21 occurs. The gas density at the location where the arc A is generated is higher than that at other locations. That is, since a high-density gas atmosphere is formed between the fixed contact 11 and the movable contact 21, the generation of the arc A (regeneration after arc zero extinction of the current of the arc A) is less likely to occur, and the gas circuit breaker is generated. It is possible to improve the blocking performance of G1.

(2) Since the gas is supplied to the location where the arc A is generated between the fixed contact 11 and the movable contact 21 by using the inner passage 21a of the tubular movable contact 21, the location where the arc A is generated It is possible to suitably supply the gas directly (from a position closer to the nozzle portion 16b) to the gas. Further, by using the inner space of the movable contactor 21, it is possible to expect space saving and simplification of the structure as compared with the case where a passage corresponding to the inner passage 21a is separately provided.

(3) When the movable contact 21 comes close to the position where a thermal puffer action occurs during the separating operation (see FIG. 2B), the connection passage 21b on the puffer mechanism 23 side that communicates with the inner passage 21a of the movable contact 21. Is arranged outside the puffer mechanism 23. That is, since a part of the gas released by the thermal puffer action is performed through the inner passage 21a of the movable contactor 21, the thermal puffer action is generated and an excessive increase in gas pressure due to the thermal puffer is suppressed. it can. Moreover, since the gas is not released into the puffer mechanism 23 when the gas pressure due to the thermal puffer rises excessively, damage to the puffer mechanism 23 can be prevented.

(Second embodiment)
Hereinafter, a second embodiment of the gas circuit breaker will be described.
The gas circuit breaker G2 of the present embodiment shown in FIG. 3 is a magnetic drive combined thermal puffer type gas circuit breaker. The gas circuit breaker G2 is used as one component of a gas insulated switchgear (not shown), and is incorporated in a tank (not shown) that stores an insulating gas such as SF ₆ gas. That is, the gas circuit breaker G2 is arranged in an atmosphere of insulating gas.

The gas circuit breaker G2 includes a fixed contactor side unit 30 having a fixed contactor 31 and a movable contactor side unit 40 having a movable contactor 41. The fixed contactor 31 of the fixed contactor side unit 30 and the movable contactor 41 of the movable contactor side unit 40 are arranged coaxially so that the movable contactor 41 performs contact/separation operation with respect to the fixed contactor 31. Is configured. Incidentally, the state on the left side of the center line of the gas circuit breaker G2 in FIG. 3 is the closed state (closed state) of the gas circuit breaker G2, and the electric path on the fixed contact 31 side and the electric path on the movable contact 41 side are connected. It is in the state of having done. The state on the right side of the center line of the gas circuit breaker G2 in FIG. 3 is the open state (blocking state) of the gas circuit breaker G2, and the electric path on the fixed contact 31 side and the electric path on the movable contact 41 side are cut off. It is in the state of having done.

In the fixed contactor side unit 30, the fixed contactor 31 has a first fixed contactor 31a and a second fixed contactor 31b made of a conductor, and the first fixed contactor 31a is radially outside and the second fixed contactor. The child 31b has a substantially cylindrical shape of concentric circles on the inner side in the radial direction. The first and second fixed contacts 31a and 31b are electrically connected to each other at locations not shown. By the way, the fixed contactor side unit 30 of the present embodiment is not provided with a function of performing thermal puffer operation or magnetic drive, and the movable contactor side unit 40 has a function of performing mechanical puffer operation, in addition to the thermal puffer operation. It is equipped with functions to perform operations and magnetic drive.

In the movable contactor side unit 40, the movable contactor 41 has a first movable contactor 41a and a second movable contactor 41b made of a conductor, and the first movable contactor 41a has a radially outer side and a second movable contactor. The child 41b has a substantially cylindrical shape of concentric circles on the radially inner side. The first and second movable contactors 41a and 41b are electrically connected to each other via the base portion 42 of the movable contactor side unit 40. The movable contactor 41 (first and second movable contactors 41a, 41b) is arranged coaxially with the fixed contactor 31 (first and second fixed contactors 31a, 31b) and supported so as to be movable in the axial direction. Has been done.

Further, the outer diameter of the first movable contactor 41a is set to be substantially the same as the inner diameter of the first fixed contactor 31a, and the first movable contactor 41a is configured to be insertable and insertable into the first fixed contactor 31a. .. The inner diameter of the second movable contactor 41b is set to be substantially the same as the outer diameter of the second fixed contactor 31b, and the second movable contactor 41b is configured to be externally fitted to the second fixed contactor 31b. The movable contactor 41 is adapted to perform a reciprocating linear motion (up and down movement in FIG. 3) along the central axis by a drive mechanism (not shown), that is, a contacting/separating motion with respect to the fixed contactor 31. The movable contactor 41 is arranged in the most protruding position in the closed state (closed state) on the left side of FIG. 3, and is arranged in the most retracted position in the opened state (blocking state) on the right side of FIG. Further, the arc runner 45, which will be described later, and the inner edge portions of the nozzle portion 46b, which operate integrally with the movable contactor 41, are in the proximity state to the second fixed contactor 31b during the operation process.

The first movable contactor 41a and the above-mentioned first fixed contactor 31a are provided on the outer peripheral side and are mainly provided for electrical circuit connection. On the other hand, the second movable contactor 41b and the second fixed contactor 31b are located on the inner peripheral side and are provided mainly for cutting the arc. That is, the first and second movable contactors 41a and 41b have the same axial projecting position, while the first and second fixed contactors 31a and 31b have the second fixed contactor 31b side relatively. It projects in the axial direction.

Therefore, when the movable contactor 41 separates from the fixed contactor 31, the first movable contactor 41a and the first fixed contactor 31a are separated first, and the second movable contactor 41b and the second fixed contactor. The separation from the child 31b is performed later so that an arc is generated between the second movable contact 41b and the second fixed contact 31b. On the other hand, regarding the connecting operation, the second movable contact 41b and the second fixed contact 31b are connected first, and the connection between the first movable contact 41a and the first fixed contact 31a is performed later.

A substantially cylindrical coil support portion 43 is coaxially provided between the first and second movable contacts 41a and 41b in the base portion 42. A drive coil 44 having a winding shape is attached to the tip of the coil support portion 43 so as to circulate around the center axis of the coil support portion 43 along the peripheral edge of the tip. An annular plate-shaped arc runner 45 is attached to the side of the drive coil 44 opposite to the coil support portion 43. The inner diameter of the arc runner 45 is slightly larger than the inner diameter of the second movable contactor 41b, and the arc runner 45 and the second movable contactor 41b are separated by a predetermined distance in the axial direction.

Here, the movable contactor 41 (first and second movable contactors 41a and 41b) and the coil support portion 43 are integrally provided on the base portion 42 of the movable contactor side unit 40, and these members and the arc runner are provided. 45 is made of a conductor. The arc runner 45 and one end of the drive coil 44 are electrically connected, and the other end of the drive coil 44 and the tip end of the coil support portion 43 are electrically connected. That is, when an arc is generated between the second fixed contactor 31b and the arc runner 45 that operates integrally with the movable contactor 41 when the second movable contactor 41b retracts from the second fixed contactor 31b, the arc is generated based on this arc. An electric current flows on a path including the coil support portion 43, the drive coil 44, and the arc runner 45, and the drive coil 44 is excited.

An insulating nozzle member 46 is attached to the base portion 42 so as to surround the second movable contact 41b, the coil support portion 43, the drive coil 44, and the arc runner 45. The nozzle member 46 has a substantially cylindrical shape, and the base end portion (the lower end portion in FIG. 3) is integrally connected to the inner surface of the front end of the first movable contactor 41a. The peripheral wall portion 46a of the nozzle member 46 extends in the axial direction sufficiently longer than the position where the arc runner 45 is provided. Further, the peripheral wall portion 46a of the nozzle member 46 is separated from the coil support portion 43, the drive coil 44, and the arc runner 45 with a predetermined distance in the radial direction.

A tip portion (upper end portion in FIG. 3) of the peripheral wall portion 46a of the nozzle member 46 is configured as a nozzle portion 46b having a shape that is folded back and extends obliquely toward the central axis direction. The tip of the nozzle portion 46 b extends near the inner peripheral edge of the arc runner 45. The inner diameter of the tip portion of the nozzle portion 46b is set to be substantially the same as the inner diameter of the second movable contactor 41b.

The substantially cylindrical space formed so as to be surrounded by the base portion 42, the peripheral wall portion 46a of the nozzle member 46, the nozzle portion 46b, the coil support portion 43, the drive coil 44, and the arc runner 45 is a heat puffer chamber (accumulation chamber). It is 47. Further, although the tip end portion of the nozzle portion 46b is extended to the vicinity of the arc runner 45, it is spaced apart from the arc runner 45 by a predetermined distance in the axial direction. That is, the narrow opening formed between the tip of the nozzle portion 46 b and the arc runner 45 functions as an injection port 47 a for the gas accumulated in the thermal puffer chamber 47. As described above, the movable contactor side unit 40 includes the thermal puffer portion P1 including the thermal puffer chamber 47. In addition, the thermal puffer chamber 47 is also provided with a through hole 43a provided in the coil supporting portion 43 in the radial direction, and also serves as an introducing passage 48 formed by the base portion 42, the coil supporting portion 43, the second movable contact 41b, and the like. It is in communication.

In addition, the movable contactor side unit 40 includes a mechanical puffer portion P2 in addition to the thermal puffer portion P1. That is, the movable contactor side unit 40 incorporates a puffer mechanism 50 having a cylinder structure for performing a mechanical puffer operation. In the puffer mechanism 50, a part of the base portion 42 has a hollow structure, and its space serves as a mechanical puffer chamber 51, and the immobile pressing portion 52 is arranged in the mechanical puffer chamber 51. That is, the puffer mechanism 50 changes the volume of the mechanical puffer chamber 51 in accordance with the axial protruding/retracting action of the movable contact 41 with respect to the immovable pressing portion 52, thereby performing the mechanical puffer action through the introduction passage 48 and the like. It is a thing.

In the process of axially projecting/retracting the movable contactor 41, the movable contactor 41 is at the most protruding position in the closed state (closed state) of the gas circuit breaker G2 shown on the left side of FIG. 31 is in a fitted state. Further, in this state, the relative position of the immobile pressing portion 52 in the mechanical puffer chamber 51 is a position where the volume of the mechanical puffer chamber 51 is maximized.

Next, as shown in FIG. 4A, in a boundary state where the movable contact 41 is in contact with or separated from the fixed contact 31, the relative position of the immobile pressing portion 52 is changed by the moving contact 41 moving backward. The machine puffer chamber 51 moves relatively to the inner side, and the volume of the machine puffer chamber 51 becomes smaller.

Next, as shown in FIG. 4B, when the tip of the fixed contact 31 is close to the arc runner 45 in the vicinity of the tip of the nozzle 46b of the movable contact 41, the movable contact 41 is further retracted. Then, the relative position of the immobile pressing portion 52 relatively moves further inside the mechanical puffer chamber 51, and the volume of the mechanical puffer chamber 51 becomes smaller.

In the open state (blocking state) of the gas circuit breaker G2 shown on the right in FIG. 3, the movable contactor 41 is at the most retracted position, and the fixed contactor 31 is sufficiently separated from the nozzle portion 46b of the movable contactor 41. It is in a state. Further, in this state, the relative position of the immovable pressing portion 52 relatively moves to the innermost side in the machine puffer chamber 51 due to the most retractable movement of the movable contactor 41, and the volume of the mechanical puffer chamber 51 becomes the minimum.

Further, a check valve 53 is provided in the mechanical puffer chamber 51 between the mechanical puffer chamber 51 and the introduction passage 48 on the second movable contact 41b side. The check valve 53 is opened when the insulating gas is introduced from the mechanical puffer chamber 51 to the introduction passage 48 side, and is closed in the opposite case. Further, the immovable pressing portion 52 is provided with a check valve 54 that opens when a gas is introduced into the mechanical puffer chamber 51 from the outside and closes the valve when the gas is introduced from the outside. The check valve 54 suppresses a large negative pressure in the mechanical puffer chamber 51 when the volume of the mechanical puffer chamber 51 increases due to the protruding operation of the movable contactor 41, and the operation of the movable contactor 41. Reduce the load. Further, the immobile pressing portion 52 is provided with a pressure adjusting valve 55 that limits the upper limit of the gas pressure in the mechanical puffer chamber 51. The pressure adjusting valve 55 opens when the gas pressure in the mechanical puffer chamber 51 becomes equal to or higher than a set pressure so that the gas can be released to the outside, and prevents the internal pressure of the mechanical puffer chamber 51 from becoming higher.

Next, the operation of the gas circuit breaker G2, particularly the breaking operation will be described.
In the closed state (closed state) of the gas circuit breaker G2 shown on the left side of FIG. 3, the tip of the fixed contactor 31 (first and second fixed contactors 31a and 31b) and the movable contactor 41 (first and second movable contact). The tips of the contacts 41a, 41b) are in a fitted state, and the electric path on the fixed contact 31 side and the electric path on the movable contact 41 side are electrically connected.

In the process of moving the movable contactor 41 backward from the closed state of the gas circuit breaker G2 to the completely opened state (blocking state) shown in the right side of FIG. 3, first, the movable contactor 41 is slightly retracted. However, in a state in which the respective tip portions of the second movable contactor 41b and the second fixed contactor 31b are near the boundary position of connection/separation shown in FIG. 4(a), the first movable contact is brought before this state. The contactor 41a and the first fixed contactor 31a are already in a separated state with a predetermined distance. That is, in the state where the connection between the second movable contactor 41b and the second fixed contactor 31b is established, the first movable contactor 41a and the first fixed contactor 31a are first separated from each other, and are separated from each other later. An arc A is generated between the second movable contact 41b and the second fixed contact 31b.

Further, with the backward movement of the movable contactor 41, the immovable pressing portion 52 relatively moves to the inner side of the mechanical puffer chamber 51 to reduce the volume of the mechanical puffer chamber 51. Then, the insulating gas existing in the mechanical puffer chamber 51 is discharged to the check valve 53 and the introduction passage 48 as indicated by an arrow a in FIG. 4A, and the second movable contactor 41b in which the initial arc A can be generated. The insulating gas density at the tip and around it is increased in advance. Incidentally, in this case, the insulating gas is also discharged near the second fixed contactor 31b even through the through hole 43a of the coil support portion 43, the thermal puffer chamber 47, and the like. That is, the movable contact 41 (the second movable contact 41) is further prepared by preparing for an arc A that may occur between the second movable contact 41b and the second fixed contact 31b and by making the vicinity thereof a high-density insulating gas atmosphere. In the process of the backward movement of the child 41b), the arc A (re-generation after arc zero extinction of the current of the arc A, etc.) occurs between the fixed contact 31 (second fixed contact 31b) and each tip. It will be a difficult situation. The gas releasing operation by the puffer mechanism 50 continues while the movable contactor 41 moves to the final retracted position shown in the right side of FIG.

Next, when an arc A occurs between the tip of the second fixed contact 31b and the tip of the second movable contact 41b, the movable contact 41 is further retracted up to the position shown in FIG. 4B. When coming, the arc A continuously generated between the tips of the second fixed contact 31b and the second movable contact 41b moves from the second movable contact 41b to the arc runner 45 side. Then, the current based on the arc A flows on the path including the coil support portion 43, the drive coil 44, and the arc runner 45, and the drive coil 44 is in the excited state.

As a result, the arc A generated between the tip portion of the second fixed contactor 31b and the inner edge portion of the arc runner 45 is orbitally driven along the tip portion and the inner edge portion as indicated by arrow b in FIG. 4(b). Then, the arc A moves in the gas at high speed. In other words, an arc extinguishing action corresponding to blowing gas relative to the arc A occurs (magnetic drive action). By the way, since the arc A circulates along the tip of the cylindrical second fixed contactor 31b, the wear of the tip of the second fixed contactor 31b by the arc A is not local but average. Become.

Further, since the arc A between the tip of the second fixed contactor 31b and the inner edge of the arc runner 45 is near the nozzle portion 46b, which is the opening of the heat puffer chamber 47, the arc A is driven to rotate. The temperature of the gas in the thermal puffer chamber 47 rises, and the volume expansion of the gas due to the temperature rise of the gas causes the pressure of the gas to be accumulated in the thermal puffer chamber 47. Incidentally, there is a concern that gas may leak from the opening between the arc runner 45 and the second movable contactor 41b in the introduction passage 48 communicating with the heat puffer chamber 47 in FIG. (Not shown), the gas pressure inside the thermal puffer chamber 47 increases.

During the backward movement of the movable contactor 41, the gas release operation by the puffer mechanism 50 continues, so the check valve 53 is continuously open. Therefore, when the gas pressure in the thermal puffer chamber 47 becomes high and the gas flows back into the mechanical puffer chamber 51 as shown by the arrow c in FIG. 4B, the gas pressure in the mechanical puffer chamber 51 is equal to or higher than the set pressure. The pressure adjusting valve 55 operates so as not to become.

Then, when the movable contactor 41 is further retracted, the tip end of the second fixed contactor 31b is separated from the inner edge of the nozzle portion 46b by the time of reaching the completely open state (blocking state) shown in the right of FIG. At a slightly separated stage, the insulating gas accumulated in the heat puffer chamber 47 or the like as shown by the arrow d in FIG. 3 vigorously urges through the gap between the tip of the second fixed contactor 31b and the inner edge of the nozzle 46b. Is released. That is, the insulating gas is vigorously blown to the arc A continuously generated between the tip of the second fixed contactor 31b and the inner edge of the arc runner 45, thereby causing an arc extinguishing action (heat. Puffer action).

As described above, also in the breaking operation of the gas circuit breaker G2 of the present embodiment, first, the mechanical puffer portion P2 operates to direct the arc A between the second fixed contactor 31b and the second movable contactor 41b. The direct gas supply is performed so that the gas atmosphere has a high density, and the initial generation of the arc A (regeneration after arc zero extinction of the current zero) is less likely to occur. Further, even if the arc A occurs, the magnetic drive by the drive coil 44 and the operation of the thermal puffer portion P1 are performed thereafter to perform more reliable arc extinguishment, so that improvement of the breaking performance can be expected. There is.

Next, the characteristic effects of this embodiment will be described.
(1) The mechanical puffer mechanism 50 that performs the gas supply operation by the separating operation of the movable contact 41 is provided, and the generation of the arc A generated between the second fixed contact 31b and the second movable contact 41b. Gas is supplied to the location, and the gas density at the location where the arc A is generated is made higher than at other locations. That is, a high-density gas atmosphere is formed between the second fixed contactor 31b and the second movable contactor 41b, so that the arc A (re-generation after arc zero extinction of the current zero) is less likely to occur. Therefore, the breaking performance of the gas circuit breaker G2 can be improved.

(2) In the movable contactor-side unit 40, the introduction passage 48 for supplying gas in the puffer mechanism 50 is provided separately from the thermal puffer chamber 47 at the location where the arc A is generated. The introduction passage 48 can be set individually. The introduction passage 48 of the present embodiment is provided around the second movable contactor 41b inside the coil support portion 43, the drive coil 44, and the arc runner 45, so that the introduction passage 48 is directly connected to the position where the arc A is generated (from the nozzle portion 46b. It is possible to preferably supply gas (from a position close to the same).

(3) The heat puffer chamber 47, the drive coil 44, and the introduction between the first movable contactor 41a that is fitted inside the first fixed contactor 31a and the second movable contactor 41b that is fitted around the second fixed contactor 31b. By arranging the passage 48 and the like, it can be expected that an efficient arrangement configuration is obtained.

The above embodiment may be modified as follows.
-In the said 1st Embodiment, although the inner side passage 21a of the cylindrical movable contactor 21 was used as a gas flow path, you may make it the aspect which uses a gas flow path other than an inner side path separately. In this case, the movable contact 21 can be formed in a columnar shape.

In the first embodiment, the puffer mechanism 23 is composed of the puffer case 24 (mechanical puffer chamber 27), the pressing plate 25, the biasing spring 26, etc., but the present invention is not limited to this. For example, a space corresponding to the puffer case 24 (mechanical puffer chamber 27) may be integrally formed with the base portion 22 of the movable contactor side unit 20. Further, the pressing plate 25 may be provided integrally with the movable contactor 21, and the biasing spring 26 may be omitted. In addition, for example, the puffer case 24 (mechanical puffer chamber 27) is set large so that the opening of the connection passage 21b communicating with the inner passage 21a thereof is accommodated in the puffer mechanism 23 during the reciprocating movement of the movable contact 21. Good.

-In the said 2nd Embodiment, it was set as the aspect which uses two each contactor like 1st and 2nd fixed contactor 31a, 31b and 1st and 2nd movable contactor 41a, 41b, However, 1 fixed A mode in which a contactor and a movable contactor are used may be used.

In the second embodiment described above, the puffer mechanism 50 is composed of the mechanical puffer chamber 51 and the immovable pressing portion 52, which are integrally formed with the base portion 42 of the movable contactor side unit 40, but is not limited to this. Absent. For example, a case member having the mechanical puffer chamber 51 may be provided separately from the base portion 42.

-In addition to the above-described modifications, the configurations of the gas circuit breakers G1 and G2 may be modified as appropriate. An insulating gas other than SF ₆ gas may be used.

11... Fixed contactor, 13... Drive coil, 17... Thermal puffer chamber, 20... Movable contactor side unit, 21... Movable contactor, 21a... Inner passage, 21b... Connection passage (opening on puffer mechanism side), 23... Puffer mechanism, 27... Mechanical puffer chamber, 31... Fixed contactor, 31a... First fixed contactor, 31b... Second fixed contactor, 40... Movable contactor side unit, 41... Movable contactor, 41a... First movable Contactor, 41b... 2nd movable contactor, 44... Drive coil, 47... Thermal puffer chamber, 48... Introduction passage, 50... Puffer mechanism, 51... Mechanical puffer chamber, G1, G2... Gas circuit breaker, A... Arc.

Claims (3)

In contrast to the arc generated when the movable contact is separated from the fixed contact in the process of cutting off the current, the magnetic force generated by the excitation of the drive coil moves the arc in the gas to move the gas relatively to the arc. Gas shutoff that uses both the arc extinguishing action of both the magnetic drive action of blowing and the thermal puffer action of accumulating the gas in the heat puffer chamber by heating the gas by the arc and blowing the accumulated gas to the arc. A vessel,
A mechanical puffer that supplies gas to an arc generation point generated between the fixed contact and the movable contact by the separation operation of the movable contact, and makes the gas density of the arc generation point higher than other locations. Further equipped with a mechanism ,
The puffer mechanism is provided in a movable contactor-side unit having the movable contactor, and the inside passage of the movable contactor in a tubular shape communicates with a mechanical puffer chamber in the puffer mechanism to cause the arc generation point. Is configured to provide gas to the
An opening on the side of the puffer mechanism of an inner passage of the movable contact is arranged outside the puffer mechanism in correspondence with a position where the thermal puffer action occurs in the process of the movable contact separating operation. A gas circuit breaker, characterized in that part of the discharge is arranged to take place using said inner passage . In contrast to the arc generated when the movable contact is separated from the fixed contact in the process of cutting off the current, the magnetic force generated by the excitation of the drive coil moves the arc in the gas to move the gas relatively to the arc. Gas shutoff that uses both the arc extinguishing action of both the magnetic drive action of blowing and the thermal puffer action of accumulating the gas in the heat puffer chamber by heating the gas by the arc and blowing the accumulated gas to the arc. A vessel,
A mechanical puffer that supplies gas to an arc generation point generated between the fixed contact and the movable contact by the separation operation of the movable contact, and makes the gas density of the arc generation point higher than other locations. Further equipped with a mechanism,
A movable contactor side unit having the movable contactor is provided with the thermal puffer chamber, the drive coil, and the puffer mechanism, and the introduction path for supplying gas to the arc generation location by the puffer mechanism is A gas circuit breaker, which is provided separately from the heat puffer chamber. The gas circuit breaker according to claim 2 ,
The fixed contact has first and second fixed contacts, the movable contact has first and second movable contacts, and the first fixed contact and the first movable contact are in a radial direction. The second fixed contactor and the second movable contactor are located on the outer side inward in the radial direction, respectively, and the second fixed contactor and the second movable contactor are located farther than the first fixed contactor and the first movable contactor are separated from each other. The second movable contactor is separated from the second movable contactor later to perform arc extinguishing between the second fixed contactor and the second movable contactor, and the first movable contactor is fitted in the first fixed contactor. A gas circuit breaker characterized in that the thermal puffer chamber, the drive coil, and the introduction passage are arranged between a contactor and a second movable contactor fitted onto the second fixed contactor. ..

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