JP2009289614A - Gas-blast circuit-breaker - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a gas-blast circuit-breaker excelling in compactness and cut-off performance and capable of surely intercepting a current from a small/medium current to a large current with small driving energy. <P>SOLUTION: A cylindrical flow guide part 46 is integrally provided on the inner peripheral side of a check valve 41. The flow guide part 46 is formed extending in parallel along the axial face of an operating rod 26 and connected smoothly with a predetermined curvature to the check valve 41 of circular plate shape. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a gas circuit breaker that utilizes a mechanical compression action and a heating and boosting action by arc heat, and in particular, efficiently controls the flow of a gas flow in a second pressure accumulating space that is accumulated by the heating and boosting action of arc heat. It relates to possible gas circuit breakers.

  In recent years, there has been a demand for a gas breaker with a large capacity capable of breaking from a small current to a large current, and also exhibits a high breaking performance all the way from a small current to a large current without increasing driving energy. It is requested. Therefore, various improvements have been made to meet such demands. For example, there is known a gas circuit breaker of a type that uses a heating pressurization action by arc heat in addition to a mechanical compression action to boost the arc extinguishing gas and blow it off the arc to shut it off.

  As this type of gas circuit breaker, a space in which pressure is increased by arc heat is arranged on both the movable contact portion side and the fixed contact portion side (see Patent Document 1), and a gas flow straightening member and a check A configuration in which an arc extinguishing gas not exposed to an arc is blown onto the arc by combining valves (see Patent Document 2) has been proposed. The former can be reduced in weight and size by reducing the pressurizing space on the movable contact portion side. In the latter case, arc-extinguishing gas that is maintained at a relatively low temperature because it is not exposed to the arc can be sprayed onto the arc, and an improvement in interruption performance can be expected.

  Hereinafter, a conventional example of a gas circuit breaker will be specifically described with reference to FIGS. 7 is a cross-sectional view showing the closing state before the breaking operation, FIG. 8 is a cross-sectional view showing the initial state of the breaking operation, FIG. 9 is a cross-sectional view showing a state near the current peak after the breaking operation is advanced, and FIG. And FIG. 11 is a cross-sectional view showing a state in which the interruption operation has further progressed to reach the current zero point. 10 corresponds to the case where the breaking current is large, and FIG. 11 corresponds to the case where the breaking current is small.

  First, an outline of the gas circuit breaker will be described. As shown in FIG. 7, in a container (not shown) filled with an arbitrary arc extinguishing gas, a first contact portion defined as a movable contact portion 1 and a fixed opposing contact portion 2 are provided. The 2nd contactor part to be defined is arrange | positioned facing the center axis | shaft of a container.

  The positional relationship of the movable contact portion 1 will be described by defining the direction on the opposite contact portion 2 side as the front and the opposite side as the rear. In addition, the space between the movable contact portion 1 and the opposed contact portion 2 is defined as an arc space where an arc is generated during the interruption operation, and is a space having the same pressure as the filling gas in the container (simply the internal space of the container). ) Is defined as a filling gas atmosphere space 14.

  The opposed contact portion 2 is fixed in the container, and the flange 40 provided with the opening 34d, the opposed arc contact 7 fixed to the flange 40, and the periphery thereof are similarly fixed to the flange 40. And the opposite energization contact 5.

  Then, the structure of the movable contact part 1 is demonstrated. The movable contact portion 1 is provided with a hollow operation rod 26. The operation rod 26 is configured to reciprocate in the axial direction by a drive device (not shown). A plurality of rod openings 34 c are formed in the middle of the operation rod 26. The rod opening 34c is for communicating the hollow portion of the operating rod 26 with the filled gas atmosphere space 14 in the container. On the outer peripheral surface of the operating rod 26, a stopper 42 is fixed near the middle between the rod opening 34c and the front end of the operating rod 26.

  A flange 27 is connected to the front end portion of the operation rod 26. A cylinder 28 is integrally provided behind the flange 27. A partition wall 35 is fixed integrally in the middle of the cylinder 28. The space in the cylinder 28 is divided into front and rear through the partition wall 35, and a thermal pressure increasing chamber 31 is provided on the front side, and a mechanical compression chamber 32 is provided on the rear side.

  An arc 38 is generated in the arc space during the interruption operation, and the thermal boosting chamber 31 is a space that takes in hot gas that has become high temperature due to the thermal energy of the arc 38 and accumulates pressure by the heating and boosting action. On the other hand, the mechanical compression chamber 32 is a space in which a circular flat plate-like fixed piston 33 is inserted, and pressure is accumulated by a mechanical compression action by the fixed piston 33 during a shut-off operation.

  In addition, a partition wall opening 34b is formed in the partition wall 35 that separates the thermal pressure increasing chamber 31 and the mechanical compression chamber 32, and the thermal pressure increasing chamber 31 and the mechanical compression chamber 32 are formed by the partition wall opening 34b. Spatial communication. Further, a floating check valve 41 is provided on the partition wall opening 34b on the thermal pressure increasing chamber 31 side. The check valve 41 is formed of a circular flat plate member, and its operation is limited by the stopper 42 and the partition wall 35.

  The fixed piston 33 in the mechanical compression chamber 32 slides with respect to the outer peripheral surface of the operating rod 26 on its inner peripheral surface, and slides with respect to the inner peripheral surface of the cylinder 28 on its outer peripheral surface. It is configured. In this case, the fixed piston 33 is fixed in a container (not shown) by a piston support portion 33b that is integrally provided behind the fixed piston 33 and extends in the axial direction. Further, the fixed piston 33 is formed with a piston opening 34e. The piston opening 34e is provided with a pressure release valve 44 stored in the closing direction by a spring 45.

  By the way, a hollow and finger-shaped movable arc contact 6 is connected to the front side of the flange 27. The movable arc contact 6 is disposed so as to be able to contact and separate from the opposed arc contact 7 on the opposed contact portion 2 side. A flange opening hole 34 a is formed in a portion of the flange 27 corresponding to the outer peripheral base of the movable arc contact 6.

  Further, an insulating nozzle 8 having a throat portion 9 and a movable energizing contact 4 are arranged on the outer peripheral portion of the flange opening hole 34a so as to surround the movable arc contact 6. The movable energizing contact 4 is disposed so as to be able to contact and separate from the opposing energizing contact 5 on the opposing contact portion 2 side.

  A gas flow path 11 is formed between the movable arc contact 6 and the insulating nozzle 8 continuously from the flange opening hole 34 a of the flange 27. The gas flow path 11 is a portion that connects the internal space of the thermal boosting chamber 31 and the arc space.

  The gas circuit breaker having the above configuration performs the shut-off operation as follows. When the blocking operation starts, the state shown in FIG. 7 is shifted to FIG. That is, the operating rod 26 moves backward, and the movable contact portion 1 including the operating rod 26 moves integrally. As a result, the operating rod 26 and the cylinder 28 move integrally with respect to the fixed piston 33 fixed in the container, and the cylinder 28 and the fixed piston 33 move relative to each other and are formed in the rear of the cylinder 28. The mechanical compression chamber 32 is compressed.

  Since the check valve 41 attached to the opening 34b of the partition wall 35 is floating at the start of the blocking operation shown in FIG. 8, it does not operate integrally with the movable contact portion 1 due to inertial force. That is, the check valve 41 has moved relatively forward, and comes into contact with the stopper 42 and stops.

  With this forward movement, the check valve 41 is opened, and the partition opening 34b of the partition 35 is opened. Further, since the pressure in the mechanical compression chamber 32 is increased, a low-temperature and high-density gas flow 39a flows from the mechanical compression chamber 32, and this gas flow 39a passes through the opening 34b from the mechanical compression chamber 32 side. Then, it is supplied to the thermal boosting chamber 31.

  Next, when the interruption operation proceeds as shown in FIG. 9 and the opposing arc contact 7 and the movable arc contact 6 are separated, an arc 38 is generated in the arc space between the arc contacts 7 and 6. At this time, the arc 38 is in a high temperature and high pressure state by the arc 38. For this reason, the arc space has a higher pressure than the thermal boosting chamber 31 and flows from the throat portion 9 of the insulating nozzle 8 to the thermal boosting chamber 31 through the gas flow path 11 and the opening 34 a of the flange 27. A gas flow 39b is produced. As a result, a part of the thermal energy of the arc 38 is taken into the thermal boosting chamber 31.

  In particular, when interrupting a large current, the arc space becomes high temperature. For example, when the current of the arc 38 is 50 kA, the temperature easily reaches 10,000 K or more. For this reason, the thermal boost chamber 31 is significantly boosted, and a reverse differential pressure is generated between the thermal boost chamber 31 and the mechanical compression chamber 32, and the thermal boost chamber 31 is more pressurized than the mechanical compression chamber 32. Becomes larger. Therefore, a backward force acts on the check valve 41 attached to the partition opening 34b of the partition wall 35, the check valve 41 moves rearward and closes, and the partition opening 34b of the partition wall 35 is closed. It becomes a state.

  It should be noted that, compared with such a large current interruption, rapid boosting does not occur in the thermal boost chamber 31 when the medium and small current interruptions (for example, 20 kA or less). Therefore, the pressures in the thermal pressure increasing chamber 31 and the mechanical compression chamber 32 are in a relatively balanced state, and the operation of the check valve 41 is the pressure state between the thermal pressure increasing chamber 31 and the mechanical compression chamber 32. It depends on.

  When the stroke further advances and the current zero point is reached as shown in FIGS. 10 and 11, the arc 38 is attenuated. And it will be in a residual arc plasma state and pressure, density, and temperature will decrease. Thereby, the throat portion 9 of the insulating nozzle 8 is sufficiently opened. At this time, the gas in the thermal pressurization chamber 31 becomes a gas flow 39c and flows from the thermal pressurization chamber 31 toward the gas flow path 11 through the opening 34a of the flange 27.

  The gas flow 39c passes through the gas flow path 11 and reaches the arc space, and enters the hollow space of the operation rod 26 and the gas flow 39f flowing from there toward the counter arc contact 7, and the rod opening of the operation rod 26 It is divided into a gas flow 39g flowing toward 34c. By these two-direction gas flows 39f and 39g, the arc 38 is synergistically and strongly cooled and extinguished, and current interruption is achieved. Note that the gas flow 39e that has passed through the opening 34c of the operation rod 26 flows out to the filled gas atmosphere space 14 (shown in FIGS. 10 and 11).

  Here, FIG. 10 shows a state where a current zero point is reached when a large current is interrupted. When the large current is interrupted, the pressure in the thermal pressure chamber 31 is higher than that in the mechanical compression chamber 32, and the check valve 41 attached to the partition wall 35 is in a closed state. On the other hand, the pressure release valve 44 provided in the fixed piston 33 is opened due to an excessive pressure increase in the mechanical compression chamber 32. Therefore, the gas flow 39 d escapes from the mechanical compression chamber 32 to the filled gas atmosphere space 14. Thereby, it can avoid that the excessive pressure of the mechanical compression chamber 32 becomes the reaction force which interrupts | blocks interruption | blocking operation | movement.

  Further, FIG. 11 shows a state where the current zero point is reached when the medium / small current is cut off. When the medium / small current is interrupted, the pressure in the thermal pressure increasing chamber 31 gradually decreases near the current zero point, and is lower than the pressure in the mechanical compression chamber 32. Therefore, the check valve 41 is opened again, and a gas flow 39a from the mechanical compression chamber 32 to the thermal pressure increasing chamber 31 is generated.

  In the gas circuit breaker as described above, the thermal pressurizing chamber 31 and the mechanical compression chamber 32 act complementarily. That is, when the arc energy is small as in the case of interrupting the medium / small current, a large pressure increase cannot be expected in the thermal boosting chamber 31, so the gas flow 39 a is supplied from the mechanical compression chamber 32 and the pressure in the thermal boosting chamber 31 increases. Can be supplemented.

  On the other hand, at the time of interrupting a large current that requires strong spraying, the arc energy is large, so that a strong gas flow 39b is supplied from the arc space to the thermal boosting chamber 31, and the pressure in the thermal boosting chamber 31 becomes extremely high. . At this time, since the thermal boosting chamber 31 is separated from the mechanical compression chamber 32 by the check valve 41, the thermal boosting chamber 31 can be boosted with high efficiency. And when it becomes a residual arc plasma state and the throat portion 9 of the insulating nozzle 8 is sufficiently opened, a strong gas flow 39c flows from the thermal pressure increasing chamber 31 through the gas flow path 11 to the arc space and reliably cuts off the current. can do.

At the time of shutting off a large current, the check valve 41 is closed to suppress the flow of arc energy into the mechanical compression chamber 32. Therefore, the pressurization of the mechanical compression chamber 32 is also suppressed to some extent, and the shut-off operation is performed. The reaction force that disturbs can be suppressed. Further, in the thermal pressurizing chamber 31, the pressure acting on the constituent members is canceled out, so that the blocking operation is not hindered.
JP 2001-67996 A JP 2003-317584 A

  However, the conventional gas circuit breaker as described above has the following problems. That is, when the pressure increase in the thermal pressure increasing chamber 31 is not sufficient as in the case of interrupting the medium / small current, the gas flow 39a is supplied from the mechanical pressure increasing chamber 32 to the thermal pressure increasing chamber 31. The gas flow 39a entering the boosting chamber 31 diffuses inside the thermal boosting chamber 31 in the process of passing through the thermal boosting chamber 31, and the pressure gradually decreases. Therefore, the pressure of the gas flow 39c flowing from the thermal pressure increasing chamber 31 to the arc space through the gas flow path 11 also decreases, and the spray pressures of the gas flows 39f and 39g sprayed on the arc 38 are weakened.

  That is, after flowing from the mechanical compression chamber 32 to the thermal pressure increasing chamber 31, the gas flow 39 a is diffused in the thermal pressure increasing chamber 31 and cannot reach the gas flow path 11 efficiently. From the viewpoint of mechanical compression, this means that the thermal pressure increasing chamber 31 exists as a dead volume of the mechanical compression chamber 32, leading to a decrease in spraying pressure when a small and medium current is interrupted.

  Therefore, conventionally, in order to obtain a sufficient blowing pressure at the time of interrupting the medium / small current, it has been considered to increase the cross-sectional area of the mechanical compression chamber 32 or to reduce the volume of the thermal pressure increasing chamber 31. However, when the cross-sectional area of the mechanical compression chamber 32 is increased, there arises a new problem that drive energy increases.

  On the other hand, when the volume of the thermal boosting chamber 31 is reduced, the interruption performance against small and medium currents is improved. On the other hand, when the large current is cut off, the pressure rises too much and the amount of gas flowing out of the thermal boosting chamber 31 Many points become a problem. That is, if the amount of gas outflow from the thermal boosting chamber 31 increases, the gas will flow out of the thermal boosting chamber 31 in a short time. In particular, when the generation time of the arc 38 is long, the gas density and pressure in the thermal pressure increasing chamber 31 are lowered, and there is a possibility that the interruption performance is lowered.

  The present invention has been proposed in order to solve the above-described problems of the prior art, and can be reliably cut off from a small to large current with a small driving energy, and has excellent compactness and cut-off performance. An object is to provide a gas circuit breaker.

  In order to achieve the above-described object, the present invention provides a first contact portion and a second contact each having a current-carrying contact and an arc contact on a central axis in an airtight container filled with an arc extinguishing gas. The child parts are arranged to face each other, and the arc contacts of the first contact part and the second contact part are in contact conduction with each other during normal operation, and are separated during the interruption operation and are separated from each other. An arc is defined in an arc space defined as a space between the contact portion and the second contact portion, and the first contact portion is cut off and put in by a connected driving device. An accumulating space for generating a gas flow for arc extinguishing is formed inside, and an insulating nozzle for blowing the gas flow in the accumulating space to the arc is installed in the accumulating space. In the shut-off process, A first pressure accumulating space accumulated by a mechanical compression action, and a second pressure accumulating space communicated with the arc space and accumulated by a heating pressure raising action by a hot gas taken in from the arc space, are provided via a partition wall, A partition opening for connecting the first pressure accumulation space and the second pressure accumulation space adjacent to each other is formed in the partition, and a check valve for closing and opening the partition opening is attached to the partition opening, In the gas circuit breaker provided with a gas passage that spatially connects the second pressure accumulation space and the arc space inside the insulating nozzle, the partition opening is provided near the partition opening through the partition opening. A flow guide portion for directing the gas flow is installed so that the gas flow flowing from the first pressure accumulation space into the second pressure accumulation space flows toward the gas passage.

  In the present invention having such a configuration, when the check valve is opened and the partition opening is in the open state, the low-temperature and high-density gas flow that has entered the second pressure accumulation space from the first pressure accumulation space is flowed. The guide portion can be smoothly guided toward the gas passage of the insulating nozzle. Therefore, the gas flow does not diffuse in all directions inside the second pressure accumulation space, and can reach the gas flow path efficiently. Therefore, gas can be flowed in a state of maintaining a low temperature and high density from the first pressure accumulation space through the second pressure accumulation space to the insulating nozzle, and even when a small and medium current interruption with a small heating pressure increase action is performed, a high blowing rate is achieved. A pressing pressure can be secured.

  Further, when an arc is generated during the interruption operation and the pressure in the arc space rises from the second pressure accumulation space, the high temperature gas in the arc space flows into the second pressure accumulation space through the gas flow path. Since the nearby flow guide part is in the vicinity of the opening of the partition wall that separates the first and second pressure accumulating spaces, it is sufficiently away from the arc space and the gas flow path.

  Therefore, for the high-temperature gas flowing into the second pressure accumulating space from the arc space side, the flow guide portion does not induce the flow, and the low-temperature gas existing in the second pressure accumulating space and the arc space The flow guide unit does not interfere with stirring and mixing with the hot gas from the side.

  That is, when the hot gas from the arc space is taken into the second pressure accumulating space, the stirring and mixing with the low temperature gas in the second pressure accumulating space can be reliably carried out, and the high temperature gas has a gas temperature in the second pressure accumulating space. Does not contribute excessively to the rise. Therefore, even when a large current is interrupted with a large heating and boosting action, the temperature in the second pressure accumulating space does not rise excessively and does not prevent the gas flow temperature when sprayed to the arc from maintaining a low temperature. Therefore, even when the flow guide portion is installed, the interruption performance at the time of interruption of a large current can be maintained at an excellent level equivalent to the conventional one.

  According to the gas circuit breaker of the present invention, the flow guide portion is installed in the vicinity of the partition opening, and the gas flow flowing from the first pressure accumulation space into the second pressure accumulation space is directed toward the gas passage of the insulating nozzle. This prevents the diffusion inside the second pressure accumulating space and ensures that the low-temperature and high-density gas flow can reach the gas flow path. Therefore, an excellent breaking performance can be obtained with a small driving energy from a small current to a large current.

  Hereinafter, a plurality of embodiments of the gas circuit breaker according to the present invention will be specifically described with reference to FIGS. In the following embodiments, the same members as those in the conventional example shown in FIGS. The same applies to the definition of the positional relationship between the movable contact portion 1 and the opposed contact portion 2. The direction on the opposed contact portion 2 side is the front, and the opposite side is the rear.

(1) First Embodiment [Configuration]
The first embodiment according to the present invention will be specifically described with reference to FIGS. 1 to 3 are cross-sectional views of the gas circuit breaker to which the first embodiment is applied, and show a state in which the breaking operation has progressed to reach the current zero point. FIG. 1 corresponds to when a large current is cut off, FIG. 2 corresponds to a case where a small and medium current is cut off, and FIG. 3 is an enlarged view of FIG.

  The structural feature of the first embodiment is that a cylindrical flow guide portion 46 is integrally provided on the inner peripheral side of the check valve 41. The flow guide portion 46 is formed to extend in the axial direction, that is, in a direction parallel to the creeping surface in the axial direction of the operation rod 26, and is smoothly connected to the circular flat check valve 41 with a predetermined curvature. ing. The length dimension a of the flow guide portion 46 is set to be smaller than the difference b between the outer diameter length and the inner diameter length of the check valve 41 (references a and b are shown in FIG. 3).

  In this embodiment, the shape and the fixing position of the stopper 42a of the check valve 41 are different from those of the conventional stopper 42 shown in FIGS. That is, the stopper 42a is not fixed to the outer peripheral surface of the operating rod 26 like the conventional stopper 42, but is made of a ring-shaped member, and surrounds the check valve 41 on the thermal pressure increasing chamber 31 side of the partition wall 35. It is fixed. The inner diameter dimension of the front end surface of the stopper 42a is set smaller than the outer diameter dimension of the check valve 41, and the operation of the check valve 41 is limited by the front end surface of the stopper 42a coming into contact with the outer periphery of the check valve 41. It is like that.

[Action and effect]
The operational effects of the first embodiment having the above-described configuration are as follows. Note that the operation at the start of the shutoff operation in the present embodiment is the same as that of the conventional example shown in FIG. 8, and therefore, the description overlapping with the conventional example is omitted. However, when the low-temperature and high-density gas flow 39a is supplied from the mechanical compression chamber 32 to the thermal pressure increasing chamber 31 at the start of the shut-off operation, the gas flow 39a after passing through the partition opening 34b of the partition 35 Thus, an action such as orientation by the flow guide portion 46 appears. This point will be described in detail later in the explanation section when the small and medium current is cut off.

  When the interrupting operation proceeds and the opposing arc contact 7 and the movable arc contact 6 are separated, an arc 38 is generated in the arc space, so that the pressure in the arc space rises from the thermal boost chamber 31. Therefore, a high-temperature gas flow 39 b is generated from the throat portion 9 of the insulating nozzle 8 to the thermal pressure increasing chamber 31 through the gas flow path 11 and the opening 34 a of the flange 27.

  The operation until the gas flow 39b is generated is the same as that of the conventional example shown in FIG. 9, but the flow of the gas flow 39b is not affected even if the flow guide portion 46 is installed. That is, the flow guide portion 46 located in the vicinity of the partition wall 35 is located farthest from the arc space in the thermal boosting chamber 31, and the length dimension a of the flow guide portion 46 is extremely short. The gas flow 39b flowing from the side is not directed. That is, the flow guide 46 does not induce the gas flow 39b flowing from the arc space side into the thermal pressure increasing chamber 31. Therefore, the gas flow 39b can be smoothly stirred and mixed with the relatively low temperature gas in the thermal pressurizing chamber 31.

  If the flow guide portion 46 is installed long in the axial direction, such gas agitation and mixing are hindered, so that the gas flow 39b stays in the vicinity of the outer peripheral surface of the operation rod 26 in the thermal pressurizing chamber 31. The gas temperature in the thermal pressurizing chamber 31 is locally increased. As a result, the temperature of the gas flow 39c when sprayed on the arc becomes high.

  On the other hand, in the present embodiment, even if the flow guide portion 46 is installed, it does not affect the gas flow 39b. The gas temperature in the thermal pressurizing chamber 31 will not rise excessively. Therefore, it is possible to reliably exhibit the same excellent shut-off performance as the conventional one.

  After the gas flow 39b flows into the thermal boosting chamber 31 as described above, when the shut-off operation further proceeds, the current zero point is reached. 1 to 3 show this state. Here, the high-current arc 38 is attenuated, resulting in a residual arc plasma state, and the pressure, density and temperature decrease. As a result, the throat portion 9 of the insulating nozzle 8 is sufficiently opened, and the gas flow 39c flows from the thermal pressure increasing chamber 31 toward the gas flow path 11 through the flange opening hole 34a of the flange 27.

  The gas flow 39 c is provided on the operation rod 26 from the gas flow 39 f flowing from the gas flow path 11 between the movable arc contact 6 and the insulating nozzle 8 toward the counter arc contact 7 and the hollow portion of the operation rod 26. The gas flow 39g flows toward the rod opening 34c. By these two-direction gas flows 39f and 39g, the arc 38 is synergistically and strongly cooled and extinguished, and current interruption is achieved.

  When the large current interruption shown in FIG. 1 is performed, the thermal pressure increasing chamber 31 is in a higher pressure than the mechanical compression chamber 32, and the check valve 41 attached to the partition wall 35 is closed. On the other hand, the pressure release valve 44 provided in the fixed piston 33 is opened due to an excessive pressure increase in the mechanical compression chamber 32, and a gas flow 39d flowing from the mechanical compression chamber 32 to the filling gas atmosphere space 14 is generated. . Therefore, it can be avoided that the excessive pressure in the mechanical compression chamber 32 becomes a reaction force that hinders the shut-off operation.

  2 and 3, the pressure in the thermal boosting chamber 31 gradually decreases near the current zero point and falls below the pressure in the mechanical compression chamber 32. Therefore, the check valve 41 is opened, and a low-temperature and high-density gas flow 39 a flows from the mechanical compression chamber 32 toward the thermal pressurization chamber 31. The gas flow 39a passes through the partition opening 34b, hits the flow guide 46, and is directed toward the outer peripheral surface of the operation rod 26.

  At this time, since the flow guide portion 46 is smoothly connected to the check valve 41 with a predetermined curvature, the gas flow 39a smoothly flows into the thermal pressure increasing chamber 31 and is reliably guided in a desired direction. Thus, the gas flow 39a does not scatter in the thermal pressurizing chamber 31. The gas flow 39 a flows along the outer peripheral surface of the operation rod 26, and becomes a gas flow 39 c toward the gas passage 11 through the opening hole 34 a of the flange 27.

  As described above, the gas flow 39a does not diffuse inside the thermal pressure increasing chamber 31, and can reach the gas flow path 11 efficiently as the gas flow 39c. Therefore, the gas flows 39a and 39c can be made to flow as a series of flows from the mechanical compression chamber 32 to the gas passage 11 through the thermal pressure increasing chamber 31 while maintaining the low temperature and high density. As a result, even when the medium and small currents are interrupted with a small heating boosting action, a high spraying pressure can be ensured, and good interrupting performance can be obtained.

  According to the first embodiment described above, the low-temperature and high-density gas flow 39a flowing from the mechanical compression chamber 32 to the thermal boost chamber 31 is caused to flow into the thermal boost chamber 31 by the flow guide 46 when the small and medium current is interrupted. Therefore, it is possible to form a flow path that smoothly leads to the upstream gas flow path 11 without diffusing, so that a good blocking performance can be obtained.

  Further, when a large current is interrupted, the flow guide portion 46 has a shape in which the high-temperature gas flow that flows into the thermal booster chamber 31 from the arc space side does not block the flow space that is stirred and mixed with the cold gas. For this reason, even when a large current is interrupted with a large heating and boosting action, an excessive increase in the gas temperature in the thermal boosting chamber 31 that is blown to the arc 38 can be suppressed, and the interruption performance equivalent to that of the conventional arc extinguishing chamber is achieved. Can be obtained. Therefore, it is possible to realize a large-capacity gas circuit breaker that exhibits good breaking performance in all current regions from a small current to a large current even with a small driving energy.

(2) Second Embodiment [Configuration]
Next, a second embodiment according to the present invention will be specifically described with reference to FIG. FIG. 4 is an enlarged cross-sectional view in a state where a current zero point is reached when a medium / small current is cut off.

  The basic configuration of the second embodiment is the same as that of the first embodiment, but is characterized in that a curvature portion 47 is provided at the end of the opening 34b on the thermal boosting chamber 31 side. The curvature portion 47 has an inclined surface or a curved surface that directs the gas flow 39 a flowing from the mechanical compression chamber 32 to the thermal pressure increasing chamber 31 toward the flow guide portion 46.

[Action and effect]
In the second embodiment having the above configuration, the following functions and effects can be obtained in addition to the functions and effects of the first embodiment. That is, since the curvature portion 47 is provided at the end of the opening 34b on the thermal pressure increasing chamber 31 side, the gas flow 39a flows into the curvature portion 47 when the gas flow 39a flows from the mechanical compression chamber 32 into the thermal pressure increasing chamber 31. Along the opening 34b. Therefore, it is possible to smoothly flow to the flow guide portion 46. Thereby, the further improvement of the small and medium current interruption can be expected.

(3) Third Embodiment [Configuration]
Next, a third embodiment according to the present invention will be described with reference to FIG. FIG. 5 is an enlarged cross-sectional view in a state where a current zero point is reached when a medium / small current is cut off. The basic configuration of the third embodiment is the same as that of the first and second embodiments described above, and the structural feature is that the front surface of the operation rod 26 that constitutes the inner wall of the thermal boosting chamber 31 is arranged on the front side. The taper surface 48 which inclines is formed. The tapered surface 48 guides the gas flow 39 a directed by the flow guide portion 46 to the gas passage 11.

[Action and effect]
In the third embodiment having the above configuration, the following unique effects can be obtained in addition to the functions and effects of the second embodiment. That is, the gas flow 39a flowing from the mechanical compression chamber 32 into the thermal pressure increasing chamber 31 is guided by the flow guide 46 to become a gas flow 39c flowing into the arc space. 39 h flows along the tapered surface 48 of the outer peripheral surface of the operation rod 26 and is guided to the gas passage 11.

  For this reason, the gas flow 39h can flow very smoothly from the flow into the thermal pressure increasing chamber 31 to the gas flow path 11, and the gas flow 39c can be stably supplied to the arc space. As described above, in the present embodiment, the tapered surface 48 is provided on the outer peripheral surface of the operation rod 26, whereby the gas flow 39c can be efficiently flowed, and the low-temperature and high-density gas in the mechanical compression chamber 32 can be effectively supplied to the arc space. Can be supplied. Thereby, it is possible to further improve the small / medium current interruption performance.

(4) Other Embodiments The present invention is not limited to the above-described embodiments, and the shape, dimensions, number of arrangements, and the like of each member can be appropriately changed, and the embodiments can be freely combined. Also good. For example, as an improvement with respect to the opening 34b, as shown in FIG. 6, an inclined opening 49 inclined with respect to the axial direction may be provided in the partition wall 35, and the same effect as the second embodiment can be obtained. Can do.

It is sectional drawing of 1st Embodiment which concerns on this invention, and shows the state which reached the current zero point at the time of large current interruption | blocking. It is sectional drawing of 1st Embodiment, and shows the state which reached the electric current zero point at the time of medium and small current interruption | blocking. The expanded sectional view of FIG. It is an expanded sectional view of 2nd Embodiment which concerns on this invention, and shows the state which reached | attained the electric current zero point at the time of medium and small current interruption. It is an expanded sectional view of the 3rd embodiment concerning the present invention, and shows the state where it reached the current zero point at the time of medium and small current interruption. It is an expanded sectional view of other embodiments concerning the present invention, and shows the state where it reached the current zero point at the time of medium and small current interruption. It is sectional drawing of the conventional gas circuit breaker, and shows the injection state before interruption | blocking operation | movement. It is sectional drawing of the conventional gas circuit breaker, and shows the state of interruption | blocking operation | movement initial stage. It is sectional drawing of the conventional gas circuit breaker, and shows the state in the large current period after opening. It is sectional drawing of the conventional gas circuit breaker, and shows the state which reached the current zero point in large current interruption. It is sectional drawing of the conventional gas circuit breaker, and shows the state which reached the electric current zero point in medium and small current interruption.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Movable contact part 2 ... Opposing contact part 4 ... Movable energizing contact 5 ... Opposite energizing contact 6 ... Movable arc contact 7 ... Opposing arc contact 8 ... Insulating nozzle 9 ... Throat part 11 ... Gas flow path 14 ... filling gas atmosphere space 26 ... operating rods 27, 40 ... flange 28 ... cylinder 31 ... thermal pressurizing chamber 32 ... mechanical compression chamber 33 ... fixed piston 34a ... flange opening hole 34b ... partition opening 34c ... rod opening 35 ... Bulkhead 38 ... Arcs 39a-39h ... Gas flow 41 ... Check valves 42, 42a ... Stopper 44 ... Pressure release valve 45 ... Spring 46 ... Flow guide portion 47 ... Curvature portion 48 ... Tapered surface 49 ... Inclined opening

Claims (6)

On the central axis in the sealed container filled with the arc-extinguishing gas, a first contact part and a second contact part each having a current-carrying contact and an arc contact are arranged to face each other,
The arc contacts of the first contact portion and the second contact portion are in contact with each other during normal operation, and are separated during a shut-off operation, and the first contact portion and the second contact portion are separated. Configured to generate an arc in an arc space defined as a space between parts,
The first contact portion is configured to operate at the time of a shut-off operation and a closing operation by a connected driving device, and a pressure accumulating space for generating a gas flow for arc extinguishing is formed therein, and An insulating nozzle that blows the gas flow in the accumulator space against the arc is installed,
In the pressure accumulating space, in the shut-off operation process, a first pressure accumulating space that is accumulated by a mechanical compression action and a second pressure accumulating space that is accumulated by a heating pressure raising action by a hot gas that communicates with the arc space and is taken in from the arc space. Are provided through a partition wall,
A partition opening that spatially connects the first pressure accumulation space and the second pressure accumulation space adjacent to each other is formed in the partition,
A check valve for closing and opening the partition opening is attached to the partition opening,
In the inside of the insulating nozzle, a gas circuit breaker provided with a gas passage that spatially connects the second pressure accumulation space and the arc space,
In the vicinity of the partition opening, a flow guide portion that directs the gas flow so that the gas flow that flows from the first pressure accumulation space to the second pressure accumulation space through the partition opening flows toward the gas passage. A gas circuit breaker characterized in that is installed.   2. The gas circuit breaker according to claim 1, wherein the flow guide portion is configured by a cylindrical or ring-shaped member disposed on a path connecting the partition opening and the gas passage.   The gas circuit breaker according to claim 1 or 2, wherein the flow guide part is provided integrally with the check valve with a predetermined curvature.   The said flow guide part was comprised from the inclination cross-section part or curved cross-section part formed in the edge part by the side of the said 2nd pressure accumulation space of the said partition opening part, The any one of Claims 1-3 characterized by the above-mentioned. The gas circuit breaker described in 1.   5. The inclined wall or curved surface for guiding the gas flow directed by the flow guide portion to the gas passage is provided on an inner wall of the second pressure accumulating space. The gas circuit breaker of any one of these.   An inner surface of the partition opening is provided with an inclined surface or a curved surface for directing a gas flow flowing from the first pressure accumulation space to the second pressure accumulation space toward the flow guide portion. The gas circuit breaker according to any one of claims 1 to 5.

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