JP6536248B2 - Gas circuit breaker - Google Patents

Description

  The present invention relates to a magnetically driven heat puffer type gas circuit breaker.

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

  The magnetic drive combined heat puffer type gas circuit breaker uses a magnetic drive function to perform relative gas spraying to the arc by rotating the arc in a gas atmosphere by the magnetic force generated by the drive coil, and the gas accumulated by the arc heat It is constructed such that a thermal puffering action is applied to the arc during the discharge of the arc. And, by the arc extinguishing action of both, more effective current interruption is possible.

Japanese Patent Application Laid-Open No. 6-290688

  By the way, when performing the current interruption in the gas circuit breaker, the arc energy varies depending on whether the interruption current is large or small, which causes a difference in the degree of heating of the gas in the heat puffer chamber and causes the pressure accumulation degree of the gas. There will be a difference. Moreover, the magnitude of the current to be cut off also makes the magnetomotive force of the coil large and small, which causes a difference in the circumferential drive of the arc. This also causes a difference in the degree of heating of the gas in the heat puffer chamber and causes a difference in the degree of pressure accumulation of the gas.

  That is, the gas pressure in the heat puffer chamber tends to be high when the large current is shut off, and the gas pressure in the heat puffer chamber tends to be low when the small current is shut off. There is a concern that the pressure and the spray amount may differ and the arc extinguishing action may vary. In particular, in the case of a gas circuit breaker which requires a wide range of current interruption, the magnitude of the interruption current at that time greatly varies, and accordingly, there is a concern that the arc extinguishing action largely varies.

  The present invention has been made to solve the above-mentioned problems, and the object thereof is to suppress the variation of the arc extinguishing action caused by the magnitude of the breaking current, and to achieve the improvement of the breaking performance. To provide the

  The gas circuit breaker which solves the above-mentioned subject moves the said arc in gas with the magnetic force which arises by excitation of a drive coil with respect to the arc which arises when moving a movable contact away from a fixed contact in the process of current interruption. Both the magnetic driving action that blows the gas relative to the arc and the heat puffer action that blows the accumulated gas against the arc by accumulating the gas in the heat puffer chamber by heating the gas by the arc energy The capacity adjustment chamber is arranged in parallel to the heat puffer chamber, the gas pressure in the heat puffer chamber is received, and the capacity adjustment chamber is placed from the heat puffer chamber side. It is variably configured such that the apparent volume of the heat puffer chamber can be increased to allow for the release of gas to the side.

  According to this configuration, the capacity adjustment chamber is provided in parallel to the heat puffer chamber, and gas is released from the heat puffer chamber side to the capacity adjustment chamber side by receiving gas pressure in the heat puffer chamber. Apparent capacity is increased. That is, in the case of interrupting a current having a relatively small current value in which the gas pressure in the heat puffer chamber tends to be low, the apparent capacity expansion of the heat puffer chamber is suppressed and a sufficient gas pressure is secured in the heat puffer chamber. However, when performing a current interrupt with a relatively large current value where the gas pressure in the heat puffer chamber tends to be high, the apparent capacity of the heat puffer chamber is expanded and the gas pressure in the heat puffer chamber becomes high. It is suppressed that it passes. As a result, the arc extinguishing action by the heat puffer is suppressed from being dispersed due to the magnitude of the breaking current, and the improvement of the breaking performance of the gas circuit breaker can be expected.

Further, in the above gas circuit breaker, it is preferable that the heat puffer chamber and the capacity adjustment chamber be arranged in parallel along the contact / separation direction of the movable contact.
According to this configuration, since the heat puffer chamber and the capacity adjustment chamber are arranged in parallel along the contact / separation direction of the movable contact, the enlargement of the gas circuit breaker in the direction orthogonal to the same direction can be suppressed.

  In the gas circuit breaker described above, when the gas pressure in the heat puffer chamber exceeds a predetermined pressure between the heat puffer chamber and the capacity adjustment chamber, the heat puffer chamber is moved from the heat puffer chamber to the capacity adjustment chamber. Preferably, a non-return valve is provided which allows one-way gas release.

According to this configuration, since the check valve is used between the heat puffer chamber and the capacity adjustment chamber, it can be realized with a relatively simple configuration.
Further, in the above-described gas circuit breaker, when a check valve allowing discharge of gas in one direction from the heat puffer chamber side to the capacity adjustment chamber side is a first check valve, the check valve from the capacity adjustment chamber side It is preferable that a second check valve is provided that allows the unidirectional discharge of gas to the outside of the room, and the second check valve is disposed inside the substantially cylindrical fixed contact.

  According to this configuration, the check valve (second check valve) allowing the one-way gas discharge from the capacity adjustment chamber to the outside of the capacity adjustment chamber is disposed inside the cylindrical fixed contact. The inner space of the fixed contact can be used effectively, which contributes to the suppression of the increase in size of the gas circuit breaker.

In the gas circuit breaker described above, preferably, the capacity adjustment chamber is configured to include a capacity variable mechanism that continuously changes its capacity by receiving the gas pressure in the heat puffer chamber.
According to this configuration, the capacity adjustment chamber is provided with a capacity variable mechanism that continuously changes its capacity by receiving the gas pressure inside the heat puffer chamber, so the gas pressure inside the heat puffer chamber is continuously adjusted. It is possible.

  ADVANTAGE OF THE INVENTION According to the gas circuit breaker of this invention, the dispersion | variation in the arc extinguishing action resulting from the magnitude | size of interruption | blocking current can be suppressed, and the improvement of interruption | blocking performance can be aimed at.

FIG. 1 is a cross-sectional view of a magnetically driven heat puffer type gas circuit breaker in one embodiment. (A)-(c) is a sectional view for explaining operation of a gas circuit breaker. It is sectional drawing of the gas circuit breaker in another example. It is sectional drawing of the gas circuit breaker in another example. It is sectional drawing of the gas circuit breaker in another example.

Hereinafter, one embodiment of a gas circuit breaker will be described.
The gas circuit breaker 10 of the present embodiment shown in FIG. 1 is a magnetically driven heat puffer type gas circuit breaker. The gas circuit breaker 10 is used as a component of a gas insulated switchgear (not shown), and is incorporated in a tank (not shown) in which an insulating gas such as SF ₆ gas is stored. That is, the gas circuit breaker 10 is disposed in the atmosphere of the insulating gas.

  The gas circuit breaker 10 is configured such that the cylindrical fixed contact 11 and the movable contact 12 are coaxially disposed, and the movable contact 12 is moved toward and away from the fixed contact 11. There is. In the gas circuit breaker 10 of this embodiment, the axial direction of the fixed contact 11 and the movable contact 12 is arranged along the vertical direction, and the fixed contact 11 is disposed on the upper side and the movable contact 12 is disposed on the lower side. Become. Incidentally, the state on the left side of the center line of the gas circuit breaker 10 in FIG. 1 is the closed state (input state) of the gas circuit breaker 10, and the electric path on the fixed contact 11 side and the electric path on the movable contact 12 side are connected. It is in a state of Further, the state on the right side from the center line of the gas circuit breaker 10 in FIG. Is in the state of blocking

  The fixed contact 11 is formed in a substantially cylindrical shape, and a coil support 13 having a substantially cylindrical shape is provided coaxially on the outside of the fixed contact 11, and the base end portions (upper end portions in FIG. 1) It has become. The coil support portion 13 is configured such that its axial length is slightly shorter than that of the fixed contact 11. At the front end (lower end in FIG. 1) of the coil support portion 13, a drive coil 14 having a winding shape is mounted so as to turn around its own center axis along the front end peripheral edge. An annular ring-shaped arc runner 15 is attached to the side (lower side in FIG. 1) opposite to the coil support portion 13 of the drive coil 14. The inner diameter of the arc damper 15 is substantially the same as the inner diameter of the fixed contact 11, and the arc runner 15 and the fixed contact 11 are separated at a predetermined distance in the axial direction.

  Here, the fixed contact 11, the coil support 13, and the arc runner 15 are made of a conductor. The arc runner 15 and one end of the drive coil 14 are electrically connected, and the other end of the drive coil 14 and the tip of the coil support 13 are electrically connected. That is, when an arc is generated between the movable contact 12 and the arc runner 15 when the movable contact 12 retracts from the fixed contact 11, the current based on this arc is the coil support portion 13 (fixed contact 11), driving It flows along a path of the coil 14 and the arc runner 15, and the drive coil 14 is excited.

  The base end of the fixed contact 11 is integrally connected to the upper case 16 which is also made of a conductor. The upper container 16 has a substantially bottomed cylindrical shape, and is provided with an intermediate wall 16b at a distance from the upper bottom 16a. That is, a space is formed by the upper bottom portion 16a, the intermediate wall portion 16b, and the peripheral wall portion 16c of the upper container 16, and the space is used as the capacity adjustment chamber 17 (the function as the capacity adjustment chamber 17 will be described later). The intermediate wall portion 16 b and the base end portion of the fixed contact 11 (coil support portion 13) are integrally connected. The intermediate wall portion 16b is connected to an axially intermediate position of the peripheral wall portion 16c, and a tip end portion (lower end portion in FIG. 1) of the peripheral wall portion 16c protrudes downward than the intermediate wall portion 16b. Further, the peripheral wall portion 16c and the coil support portion 13 are separated with a predetermined distance in the radial direction.

  An insulating nozzle member 18 is attached to the end of the peripheral wall portion 16c. The nozzle member 18 has a substantially cylindrical shape, and the base end (upper end in FIG. 1) is integrally connected to the tip of the peripheral wall 16 c of the upper container 16. The peripheral wall 18 a of the nozzle member 18 is axially extended continuously from the peripheral wall 16 c of the upper container 16 in the axial direction. That is, the peripheral wall portion 18 a of the nozzle member 18 is also separated from the coil support portion 13 with a predetermined distance in the radial direction. The peripheral wall portion 18 a of the nozzle member 18 is extended in the axial direction sufficiently longer than the position where the arc runner 15 is provided.

  The tip end portion (lower end portion in FIG. 1) of the peripheral wall portion 18a of the nozzle member 18 is configured as a nozzle portion 18b having a shape that obliquely extends in the central axis direction so as to be folded back. The tip end of the nozzle portion 18 b extends near the inner peripheral edge of the arc runner 15. The inner diameter of the tip portion of the nozzle portion 18 b is set to be substantially the same as the inner diameter of the arc runner 15 and the fixed contact 11.

  A substantially cylindrical space is formed so as to be surrounded by the intermediate wall 16b, the peripheral wall 16c, the peripheral wall 18a of the nozzle member 18, the nozzle 18b, the coil support 13, the drive coil 14 and the arc runner 15 of the upper container 16 As a heat puffer room (accumulation room) 19. The tip of the nozzle portion 18b extends near the arc runner 15, but is spaced apart from the arc runner 15 by a predetermined distance in the axial direction. That is, the narrow opening formed between the tip of the nozzle portion 18 b and the arc runner 15 functions as an injection port 19 a of the gas accumulated in the heat puffer chamber 19.

  A check valve 20 is formed in a portion near the outer periphery of the intermediate wall portion 16 b of the upper container 16 which forms a part of the heat puffer chamber 19. In the check valve 20, a plate-like valve body 20a is disposed so as to close the opening on the opposite side (upper bottom portion 16a side) to the heat puffer chamber 19 with respect to the through hole 16d formed in the intermediate wall portion 16b. The valve body 20a is configured to be biased by the biasing spring 20b so as to close the through hole 16d. As a function of the check valve 20, when the gas accumulated in the heat puffer chamber 19 exceeds a predetermined pressure, the valve body 20a is separated from the through hole 16d against the biasing force of the biasing spring 20b. Thus, the check valve 20 opens. As a result, the heat puffer chamber 19 communicates with the volume adjustment chamber 17, and the pressure increase of the gas in the heat puffer chamber 19 is suppressed.

  Incidentally, as one configuration example of the check valve 20, a plurality of through holes 16d are provided at equal intervals in the circumferential direction of the intermediate wall portion 16b, and each through hole 16d is formed in an arc shape of a predetermined length in the circumferential direction. Ru. Further, the valve body 20a is an annular plate-like member capable of simultaneously closing all the through holes 16d, and the biasing springs 20b are respectively disposed between the through holes 16d.

  At the central portion of the middle wall portion 16 b of the upper container 16, a check valve 21 is formed at the inner portion of the fixed contact 11 having a substantially cylindrical shape. In the check valve 21, a substantially plate-like valve body 21a is disposed so as to close the opening on the fixed contact 11 side with respect to the through hole 16e formed in the intermediate wall portion 16b, and the valve body 21a is formed through the through hole 16e. It is configured to be biased by a biasing spring 21b so as to close it. As a function of the check valve 21, when the gas pressure on the fixed contact 11 side (the heat puffer chamber 19 side) becomes relatively lower than that on the capacity adjustment chamber 17 side, the valve body 21a is biased by an urging spring 21b. By separating from the through hole 16e against the biasing force of the valve, the check valve 21 is opened, and the gas accumulated in the volume adjustment chamber 17 is released.

  The movable contact 12 is made of a conductor and has a substantially cylindrical shape. The outer diameter of the movable contact 12 is set to be substantially the same as the inner diameter of the fixed contact 11, and the movable contact 12 is configured to be able to be inserted and fitted to the fixed contact 11. The movable contact 12 is configured to perform a reciprocating linear operation (up and down movement in FIG. 1) along the central axis by a drive mechanism (not shown), that is, a contact / separation operation with respect to the fixed contact 11. Also, even when the movable contact 12 passes through the inner edge portion of the arc runner 15 and the inner edge portion of the nozzle portion 18b, the movable contact 12 substantially contacts or approaches each inner edge portion having substantially the same setting as the inner diameter of the fixed contact 11. It will be in the state of

Next, the operation of the gas circuit breaker 10, particularly the shutoff operation, will be described.
In the closed state (input state) of the gas circuit breaker 10 shown on the left side of FIG. 1, the tip of the movable contact 12 is inserted into the fixed contact 11, and the electric path on the fixed contact 11 side The electric path on the movable contact 12 side is electrically connected.

  In the process of moving the movable contact 12 downward from the closed state of the gas circuit breaker 10 to the complete open state (cut-off state) shown on the right side of FIG. For example, in the state of FIG. 2A in which the tip of the movable contact 12 is slightly separated from the fixed contact 11, for example, between the tip of the movable contact 12 and the tip of the fixed contact 11 Arc A occurs.

  Next, in a situation where the movable contact 12 is further retracted and the arc A continues without arc extinction, the arc A generated at the tip of the movable contact 12 shifts from the fixed contact 11 to the arc runner 15 side. For example, in the state of FIG. 2 (b), an arc A is generated between the tip of the movable contact 12 and the inner edge of the arc runner 15. Then, a current based on the arc A flows in the path of the coil support 13 (fixed contact 11), the drive coil 14 and the arc runner 15, and the drive coil 14 is excited.

  As a result, the arc A generated between the tip of the movable contact 12 and the inner edge of the arc runner 15 is circumferentially driven along the tip and the inner edge as shown by the α arrow in FIG. Arc A moves in the gas at high speed. In other words, an arc extinguishing action equivalent to blowing a gas relative to the arc A is generated (magnetic drive action). Incidentally, since the arc A circulates along the tip of the cylindrical movable contact 12, wear due to the arc A of the tip of the movable contact 12 is not local but is made average.

  Further, since the arc A between the tip of the movable contact 12 and the inner edge of the arc runner 15 is in the vicinity of the nozzle portion 18 b which is the opening of the heat puffer chamber 19, the heat puffer is driven by the arc A going around. The temperature of the gas in the chamber 19 rises. Further, in this case, since the movable contact 12 is inserted so as to close the opening of the inner edge portion of the nozzle portion 18b, the pressure accumulation of the gas is made in the heat puffer chamber 19 with the temperature rise of the previous gas. .

  Then, when the movable contact 12 is further retracted and the tip of the movable contact 12 is slightly separated from the inner edge of the nozzle portion 18b, for example, as shown in FIG. 2 (c), the heat puffer shown in FIG. The gas accumulated in the chamber 19 is vigorously released from the gap between the tip of the movable contact 12 and the inner edge of the nozzle portion 18b. That is, when the arc A continues between the tip of the movable contact 12 and the inner edge of the arc runner 15, the arc extinguishing action occurs by blowing the gas from the nozzle portion 18b toward the arc A. It has become (heat puffer function).

  Here, as in the present embodiment, the heat puffer chamber 19 has a capacity adjustment chamber 17 juxtaposed with the capacity adjustment chamber 17 via the check valve 20, and the conventional structure (capacity adjustment) in which the capacity (volume) of the heat puffer chamber is constant. Let's compare with the one with the structure without a room from the viewpoint of the current interruption performance.

  If the arc energy is different depending on the size of the breaking current, the degree of heating of the gas is different, so in the conventional structure in which the capacity of the heat puffer chamber is constant, there is a difference in the pressure accumulation degree of the gas. A difference arises and the arc extinguishing action by the heat puffer disperses. Therefore, when the capacity of the heat puffer chamber etc. is set to a small capacity according to the smaller one of the shutoff current, the gas pressure of the heat puffer chamber becomes too high when the large current is interrupted, and the gas blows rapidly. In particular, there is a risk that the gas blowing will be insufficient near the current zero point where gas blowing is required (an arc is likely to occur immediately after the alternating current zero point). On the other hand, when the heat puffer chamber is set to a large capacity in accordance with the larger one of the shutoff current, the gas pressure of the heat puffer chamber may not be so high when the small current is shut off, and there may be a shortage of gas spraying. . In any setting, the arc extinguishing effect varies depending on the magnitude of the breaking current. This becomes more remarkable as the cutoff current becomes wider.

  On the other hand, in the present embodiment, when the gas pressure in the heat puffer chamber 19 is lower than a predetermined pressure, the check valve 20 does not open, and the heat puffer chamber 19 functions alone. On the other hand, when the gas pressure in the heat puffer chamber 19 exceeds a predetermined pressure, the check valve 20 is opened, the heat puffer chamber 19 and the capacity adjustment chamber 17 are in communication with each other, and the capacity is expanded. Gas pressure rise is suppressed. In other words, in order to make the gas pressure in the heat puffer chamber 19 an appropriate pressure, the selection of the biasing spring 20 b of the check valve 20 is mainly made.

  That is, when a current with a relatively small current value is cut off so that the gas pressure in the heat puffer chamber 19 becomes equal to or less than a predetermined pressure, the volume etc. is set so that pressure accumulation of gas is performed by the heat puffer chamber 19 alone. It is possible to sufficiently increase the gas pressure in the heat puffer chamber 19 even with a small current interruption. On the other hand, when interrupting a current having a relatively large current value such that the gas pressure in the heat puffer chamber 19 exceeds a predetermined pressure, the check valve 20 is opened to open the heat puffer chamber 19 and the capacity adjustment chamber 17. By setting the pressure accumulation of gas together, it is possible to prevent the gas pressure in the heat puffer chamber 19 from becoming excessively high due to large current interruption. As described above, in the present embodiment, the arc extinguishing action by the heat puffer is suppressed from being dispersed due to the magnitude of the breaking current, and the breaking performance of the gas circuit breaker 10 is improved.

  During the arc extinguishing operation by the heat puffer, the gas pressure on the heat puffer chamber 19 side is lower than that on the capacity adjustment chamber 17 side, so the other check valve 21 is opened, and the gas in the capacity adjustment chamber 17 is opened. The pressure is reduced. By reducing the pressure in the capacity adjustment chamber 17, the gas can be released to the capacity adjustment chamber 17 through the check valve 20 when the gas pressure in the heat puffer chamber 19 becomes excessive after the next time. . Further, the check pressure of the check valve 21 is not only during the heat puffer operation but the gas pressure on the heat puffer chamber 19 side is relatively lower than that on the capacity adjustment chamber 17 side (the gas pressure on the capacity adjustment chamber 17 is a heat puffer The valve is opened relatively higher than the chamber 19 side, and the gas pressure on the side of the capacity adjustment chamber 17 is always equal to or less than that of the heat puffer chamber 19 side. Further, when the check valve 21 is opened, gas is positively supplied to an arc generation point such as the tip of the movable contact 12 through a path passing from the check valve 21 to the inside of the fixed contact 11. The improvement of the arc extinguishing effect can also be expected.

Next, characteristic effects of the present embodiment will be described.
(1) The capacity adjustment chamber 17 is provided in parallel to the heat puffer chamber 19, and the gas pressure in the heat puffer chamber 19 causes the gas to be released from the heat puffer chamber 19 to the capacity adjustment chamber 17 side. The apparent capacity of the puffer room 19 is increased. That is, in the case of interrupting a current having a relatively small current value in which the gas pressure in the heat puffer chamber 19 tends to be low, the check valve 20 does not open and the apparent capacity expansion of the heat puffer chamber 19 is suppressed. The check valve 20 is used to shut off a current having a relatively large current value which tends to increase the gas pressure in the heat puffer chamber 19 while securing a sufficient gas pressure in the heat puffer chamber 19. By opening the valve, the apparent capacity of the heat puffer chamber 19 is expanded, and the gas pressure in the heat puffer chamber 19 can be prevented from becoming excessively high. Thereby, it can suppress that the arc extinguishing effect | action by a heat puffer varies with the magnitude | size of interruption | blocking current, and can aim at the improvement of the interruption | blocking performance of the gas circuit breaker 10. FIG.

  (2) Since the heat puffer chamber 19 and the capacity adjustment chamber 17 are juxtaposed along the vertical direction (the contact / separation direction of the movable contact 12), the gas circuit breaker in the direction (horizontal direction) orthogonal to the same direction The enlargement of 10 is suppressed.

(3) Since the check valve 20 is used between the heat puffer chamber 19 and the capacity adjustment chamber 17, it can be realized with a relatively simple configuration.
(4) The check valve 21 allowing the one-way gas discharge from the side of the capacity adjustment chamber 17 to the outside thereof (in the present embodiment, the inner space of the fixed contact 11 communicating with the heat puffer chamber 19) is substantially cylindrical Since it arrange | positions inside the fixed contact 11 which makes these, the inner space of the fixed contact 11 can be used effectively, and it can contribute to suppression of the enlargement of the gas circuit breaker 10. FIG.

The above embodiment may be modified as follows.
-Although the check valves 20 and 21 of the above-mentioned embodiment were composition which carries out lift operation of valve bodies 20a and 21a, they are composition of performing other operations, such as swing operation, of valve bodies 20a and 21a. May be In addition, the valve bodies 20a and 21a may have other shapes such as a ball shape.

  In the above embodiment, the check valve 20 provided for the through hole 16 d to release the gas in the heat puffer chamber 19 to the capacity adjustment chamber 17 side, the gas in the capacity adjustment chamber 17 outside the heat puffer Although the check valve 21 provided separately for the through hole 16 e to be discharged to the inner space of the fixed contact 11 communicating with the chamber 19 is separately provided, the invention is not limited thereto.

  For example, in the gas circuit breaker 10a shown in FIG. 3, the valve body 22a in the capacity adjustment chamber 17 is biased to close the valve body 22a having substantially the same diameter as the inner diameter of the peripheral wall portion 16c, the through hole 16d and the through hole 16e. The check valve 22 is provided with a biasing spring 22b, and the through hole 16d and the through hole 16e are simultaneously opened and closed by the valve body 22a. The upper bottom portion 16a is provided with a through hole 16f for preventing back pressure from acting on the valve body 22a. Even with this configuration, the heat puffer chamber 19 receives the gas pressure, the check valve 22 is opened, and the gas is released from the heat puffer chamber 19 side to the capacity adjustment chamber 17 side. The apparent capacity of the chamber 19 is increased. That is, similarly, the arc extinguishing action by the heat puffer is suppressed from being varied depending on the magnitude of the breaking current.

  Further, the check valve 22 functions as a capacity variable mechanism which continuously changes the capacity of the capacity adjustment chamber 17 by receiving the gas pressure in the heat puffer chamber 19. Therefore, it is possible to adjust the gas pressure in the heat puffer chamber 19 continuously. In that sense, the capacity variable mechanism 23 of the gas circuit breaker 10b shown in FIG. 4 and the capacity variable mechanism 24 of the gas circuit breaker 10c shown in FIG. 5 function in the same manner.

  In the gas circuit breaker 10b shown in FIG. 4, a bulging portion 16x is provided upward from the upper bottom portion 16a of the upper container 16, and the capacity variable mechanism 23 is incorporated in the capacity adjusting chamber 17 in the bulging portion 16x. The variable displacement mechanism 23 includes a pressure receiving plate 23 a and a biasing spring 23 b, and when the pressure receiving plate 23 a receives gas pressure in the heat puffer chamber 19, it retracts against the biasing force of the biasing spring 23 b. It is configured to continuously change the volume of the adjustment chamber 17 itself. Incidentally, as shown by the broken line arrows in FIG. 4, slits, holes (not shown), etc. are provided in the fixed contact 11 and the coil support 13, and the heat puffer chamber 19 and the capacity adjustment chamber 17 communicate with each other. There is. By providing such a capacity variable mechanism 23, it is possible to continuously change the capacity of the capacity adjustment chamber 17 itself and to adjust the gas pressure in the heat puffer chamber 19 continuously.

  In the gas circuit breaker 10c shown in FIG. 5, a bulging portion 16y is provided laterally from the peripheral wall portion 16c of the upper container 16, and the capacity variable mechanism 24 is incorporated in the capacity adjusting chamber 17 in the bulging portion 16y. The variable displacement mechanism 24 includes a pressure receiving plate 24a and a biasing spring 24b, and operates in the same manner as the variable displacement mechanism 23 described above. That is, this is a modified example in which the position of the bulging portion 16y including the capacity variable mechanism 24 is changed.

  In addition to the above, the configurations of the gas circuit breakers 10, 10a, 10b, and 10c may be changed as appropriate.

  10, 10a, 10b, 10c: gas circuit breaker, 11: fixed contact, 12: movable contact, 14: drive coil, 17: capacity adjustment chamber, 19: heat puffer chamber, 20: check valve (check valve (check valve) 1st check valve) 21 check valve (2nd check valve) 22 check valve (check valve, variable capacity mechanism) 23 variable capacity mechanism 24 variable capacity mechanism A arc.

Claims (3)

With respect to the arc generated when moving the movable contact away from the fixed contact in the process of the current interruption, the arc is moved in the gas by the magnetic force generated by the excitation of the drive coil, and the gas is relative to the arc Gas blocking which combines the arc extinguishing action of the magnetic driving action and the heat puffer action of squeezing the accumulated gas in the heat puffer chamber by heating the gas by arc energy. And it is
A capacity adjusting chamber is provided in parallel to the heat puffer chamber, and gas pressure in the heat puffer chamber allows release of gas from the heat puffer chamber side to the capacity adjusting chamber side to make the appearance of the heat puffer chamber It is variably configured to increase the upper capacity ,
Between the heat puffer chamber and the capacity adjustment chamber, unidirectional gas discharge from the heat puffer chamber to the capacity adjustment chamber is permitted when the gas pressure in the heat puffer chamber exceeds a predetermined pressure. The first check valve is provided, and
A second check valve is provided to allow the discharge of gas in one direction from the capacity adjustment chamber side to the outside of the capacity adjustment chamber, and the second check valve is disposed inside the substantially cylindrical fixed contact. A gas circuit breaker characterized by becoming . With respect to the arc generated when moving the movable contact away from the fixed contact in the process of the current interruption, the arc is moved in the gas by the magnetic force generated by the excitation of the drive coil, and the gas is relative to the arc Gas blocking which combines the arc extinguishing action of the magnetic driving action and the heat puffer action of squeezing the accumulated gas in the heat puffer chamber by the gas heating by the arc energy. And it is
A capacity adjusting chamber is provided in parallel to the heat puffer chamber, and gas pressure in the heat puffer chamber allows release of gas from the heat puffer chamber side to the capacity adjusting chamber side to make the appearance of the heat puffer chamber It is variably configured to increase the upper capacity,
A gas circuit breaker characterized in that the capacity adjusting chamber is provided with a capacity variable mechanism which continuously changes its capacity by receiving a gas pressure in the heat puffer chamber. In the gas circuit breaker according to claim 1 or 2 ,
A gas circuit breaker characterized in that the heat puffer chamber and the capacity adjustment chamber are arranged in parallel along the contact / separation direction of the movable contact.