JP4601364B2 - Vacuum circuit breaker - Google Patents

Description

  The present invention relates to a vacuum circuit breaker for electric power using a vacuum valve, and more particularly to an insulating support structure for a vacuum valve.

  In a vacuum circuit breaker, a three-phase breaker is usually supported by an insulating support structure, and a three-phase terminal conductor drawn from both ends of the breaker is placed in the air, ensuring an insulation distance between the phases and the ground. It is configured as follows. As a conventional technique related to an insulating support structure for a circuit breaker of such a vacuum circuit breaker, for example, a back surface portion, a pair of side plate portions provided at both ends of the back surface portion, and a back surface portion and a side plate portion are surrounded. Two partition portions that divide the space into three spaces arranged in the horizontal direction, and a plate-shaped blocking portion support portion that is provided so as to partition the three spaces up and down at a position closer to the lower side than the upper portion of the partition plate An insulating support frame is disclosed. And a vacuum valve is supported by each above-mentioned interception part support part, respectively, and a three-phase vacuum circuit breaker is constituted. The support part of the vacuum valve connects the terminal conductor extending in the horizontal direction to the conductor part led out from the fixed contact side of the vacuum valve, and attaches the terminal conductor to the interrupting part support part, so that the vacuum is passed through the terminal conductor. The valve is supported by an insulating frame (see Patent Document 1).

JP 2001-275214 A (2nd page, FIG. 1 and FIG. 7)

  The conventional vacuum circuit breaker is configured as described above, and the vacuum valve is firmly supported and fixed to a flat plate-shaped circuit breaker support part via a terminal conductor. For this reason, when the movable contact collides with the fixed contact by the closing operation of the circuit breaker, the impact force acts as a repulsive force at the breaker support part and acts in the opposite direction, and chattering may occur at the contact part. As a method for reducing the impact force at the time of charging, a method such as reducing the plate thickness of the blocking portion support portion is used. However, since it is necessary to secure a predetermined support strength, chattering is prevented only by this method. It was difficult. If chattering occurs, there is a problem that the contact surface becomes rough and the withstand voltage performance deteriorates.

  The present invention has been made to solve the above problems, and an object of the present invention is to obtain a vacuum circuit breaker that alleviates the impact of the contact portion when the circuit breaker is turned on and suppresses chattering.

In the vacuum circuit breaker according to the present invention, a blocking section accommodating chamber is formed around a reference axis line, with a part left as an open end and the other portion surrounded by an insulating wall in a substantially U shape. An insulating frame provided with a blocking portion mounting plate perpendicular to the axis in the vicinity of one end side in the axial direction, and provided so as to project to the open end side of the blocking portion receiving chamber or the opposite side perpendicular to the axis. And a cylindrical vacuum valve that is arranged with its axis aligned on the axis of the shut-off section accommodating chamber, with a fixed-side conductor leading out from one end side and a movable-side terminal leading out from the other end side. In the vacuum circuit breaker in which the vacuum valve is supported and fixed to the insulating frame by attaching the fixed side conductor of the vacuum valve to the fixed side terminal and fixing the fixed side terminal to the cutoff unit mounting plate, , Fixed at least to the fixed terminal on the part perpendicular to the axis An opening portion of the connection part does not interfere size of the conductor is provided, is formed with a slit toward the open end side from the opening, the fixed terminal has an opposing portion facing the slit These are fastened and fixed by bolts penetrating the slit through the washer at the position of the slit of the blocking portion mounting plate.

According to the vacuum circuit breaker of the present invention, an opening is provided in the breaker mounting plate to which the vacuum valve is attached via the fixed side terminal, a slit is formed from the opening toward the open end , and the washer is positioned at the slit. The fixed terminal is fixed to the breaker mounting plate with a bolt that penetrates the slit through the slit, so the impact load when the vacuum valve is turned on is alleviated by the deflection of the blocking unit mounting plate, and the contact part between the fixed contact and the movable contact Chattering that occurs can be suppressed. For this reason, it is possible to provide a highly reliable vacuum circuit breaker that suppresses contact surface roughness and prevents a decrease in withstand voltage performance.

Embodiment 1 FIG.
1 is a plan view of a vacuum circuit breaker according to Embodiment 1 of the present invention, and FIG. 2 is a side cross-sectional view as seen from II-II in FIG. In the figure, a cylindrical vacuum valve 1 forming a shut-off portion has a fixed contact 1b and a movable contact 1c arranged and accommodated on the axis of a vacuum vessel 1a, and a fixed contact 1b from one end of the vacuum vessel 1a. The fixed-side conductor 1d connected to is led out, and the movable-side conductor 1e connected to the movable contact 1c is led out from the other end.

  The fixed side conductor 1d of the vacuum valve 1 is connected to a fixed side terminal 2 that protrudes in a direction perpendicular to the axis, and the movable side conductor 1e is connected to a movable side terminal that protrudes in the direction perpendicular to the axis through a flexible conductor 3. 4 is connected. An insulating operation member 5 is coaxially connected to the movable conductor 1e. The insulation operation member 5 has operation shafts 7a and 7b on both sides of the insulation member 6, and the operation shaft 7a on one end side is fastened to the movable conductor 1e with the flexible conductor 3 interposed therebetween. The operation shaft 7b on the other end side is provided with a connecting member 8 that can slide and move to the operation shaft 7b, and a contact pressure spring 9 is inserted between the connecting member 8 and the insulating member 6. . The insulation operation member 5 is comprised by 6-9. The insulating operation member 5 is coupled to the drive shaft 11 via the lever 10, and the rotational force of the drive shaft 11 is transmitted to the insulating operation member 5.

The vacuum valve 1, the fixed side terminal 2, the movable side terminal 4, the insulating operation member 5, and the like configured as described above are accommodated and supported in an insulating frame. Therefore, the configuration of this insulating frame will be described. When the axis of the vacuum valve 1 is used as a reference axis, the insulating frame 12 is cut off by surrounding the axis with the open end and surrounding the other part with an insulating wall 13 in a substantially U shape. A portion accommodating chamber 14 is formed, and a blocking portion mounting plate 15 (details will be described later) is provided in the vicinity of the end of one end side (upper side in the figure) of the blocking portion receiving chamber 14 in the axial direction, perpendicular to the axis. Furthermore, a movable terminal mounting plate 16 is provided near the open end side of the blocking portion accommodation chamber 14 in the vicinity of the central portion in the axial direction.
The insulating frame 12 shown in FIGS. 1 and 2 is for one phase. In the case of three phases, the same three are arranged in close contact with each other in the horizontal direction or arranged with a gap therebetween, and are driven by the same drive shaft. Alternatively, the three phases may be connected to form an integral insulating frame.

  FIG. 3 is a perspective view showing an example of an insulating frame in the case of three-phase integration. The insulating frame 12 is usually integrally molded with an unsaturated polyester resin or the like. As shown in the figure, one part is an open end and the other part is surrounded by an insulating wall 13 in a substantially U-shape to form a blocking part accommodating chamber 14, and three open ends are arranged in the horizontal direction with the open end directed in the same direction. It is formed in a connected shape. A blocking portion mounting plate 15 is provided in the vicinity of one end side in the axial direction of the blocking portion accommodation chamber 14, and a movable terminal mounting plate 16 is provided in the vicinity of the center portion.

  Note that the “substantially U-shape” mentioned above includes a shape having a corner portion formed at a right angle, a shape having a curved surface as shown in the figure, and a shape close to a U-shape. . For example, in the case of a three-phase integrated insulating frame, the back side and the side may be covered with a flat insulating frame, and a partition plate may be provided between the phases to form a blocking portion accommodation chamber.

  Next, a method for supporting and fixing each component to the insulating frame 12 will be described. As shown in FIG. 2, the vacuum valve 1 is arranged with the fixed-side conductor 1d facing upward and the axis of the vacuum valve 1 aligned with the reference axis, and the fixed-side terminal 2 is connected to the bolt 17 by the fixed-side conductor 1d. It is fixed by. And this fixed side terminal 2 is bolted and attached to the blocking part mounting plate 15 so as to protrude toward the open end side of the blocking part accommodation chamber 14. That is, the vacuum valve 1 is supported and fixed to the insulating frame 12 via the fixed terminal 2. The movable terminal 4 is fixed to the movable terminal mounting plate 16 by bolting so as to protrude toward the open end side together with one end side of the flexible conductor 3 connected to the movable side conductor 1e. The drive shaft 11 for rotating the lever 10 pin-coupled to the connecting member 8 of the insulating operation member 5 is not shown, but its bearing portion is supported and fixed to the insulating frame 12. Further, the drive shaft 11 is connected to an output shaft of an operation mechanism (not shown), and is driven electrically or manually so that the vacuum valve 1 opens and closes.

  Next, the detailed shape of the blocking portion mounting plate 15 provided on the insulating frame 12, which is a characteristic part of the invention according to the present embodiment, will be described. As shown in FIG. 1, a fixed-side conductor 1 d and a fixed-side terminal 2 are connected to a blocking portion mounting plate 15 that is integrally formed with an insulating wall 13 that is substantially U-shaped when viewed from above. An opening 15a is provided to avoid interference with the bolts 17 and washers 18 as connecting parts. Since this opening 15a is also related to the bending of the blocking member mounting plate 15 described later, it is desirable that the opening 15a be as large as possible in terms of strength.

  Further, the blocking portion mounting plate 15 is provided with a slit 15b so as to divide the blocking portion mounting plate 15 into two from the opening 15a toward the open end side of the blocking portion accommodation chamber 14. When the blocking portion mounting plate 15 is viewed from the direction of the thick arrow in FIG. 1, the slit 15 b is formed at substantially the center in the width direction, that is, on the axis line in the lead-out direction of the fixed terminal 2. Using the slit 15b formed in this way, the fixed side terminal 2 is fastened and fixed to the blocking portion mounting plate 15 by the fixing bolt 20 via the washer 19. FIG. 4 is a partially enlarged view of the blocking portion mounting plate 15 showing the shape of the slit portion. The slit width T is set to be slightly larger than the outer diameter of the fixing bolt 20 for fixing the fixed side terminal 2 to the blocking portion mounting plate 15 as shown in FIG. Only the position of the bolt 20 may be formed in a hole shape slightly larger than the outer diameter of the fixing bolt 20, and the other part may be formed with a narrower width t.

  Next, the operation will be described. When the vacuum valve 1 as shown in FIG. 2 is in an open state, the lever 10 is rotated in the clockwise direction by driving the drive shaft 11 in a clockwise direction from an operation mechanism (not shown) in response to the closing command, so that the insulating operation unit 5 Is moved upward, and the movable contact 1c connected thereto moves upward and comes into contact with the fixed contact 1b. After both contacts are brought into contact, the connecting member 8 of the insulating operation unit 5 further slides the operation shaft 7b and pushes up the contact pressure spring 9 by a predetermined dimension, so that the rotation of the lever 10 is stopped and the vacuum valve 1 is turned on. It becomes. In the closed state, the movable contact 1 c is pressed by the spring force of the contact pressure spring 9 to keep the contact. At the time of release, the drive shaft 11 is rotated counterclockwise by the release command, the contact pressure spring 9 is released, both contacts are released, and the state returns to the state of FIG. 2, and the vacuum valve 1 is opened.

  Next, the operation of the blocking portion mounting plate 15 provided on the insulating frame 12 will be described. The blocking portion mounting plate 15 needs to be able to withstand the impact force when the vacuum valve 1 is turned on, while supporting the fixed terminal 2, the vacuum valve 1, the insulating operation portion 5, and the like. For this reason, it has a thickness that can ensure the required strength, and is fixed to the insulating wall 13 of the insulating frame 12. However, looking at the movement of the contact when the vacuum valve 1 is turned on, when the movable contact 1c collides with the fixed contact 1b by the closing operation, an impact load of about 2 to 3 times the contact pressure spring load is applied. This impact force is transmitted to the blocking portion mounting plate 15. As a result, a repulsive force is generated and both contacted contacts act in the opening direction to open the contact portion, which is then pushed back by the contact pressure spring 9 and closed again, that is, chattering may occur. Since a voltage is applied to both contacts, an arc is generated by chattering. The contact portion melts slightly due to the arc. If the contact part melts and peels repeatedly, the contact surface becomes rough and the withstand voltage performance decreases.

  Therefore, in the invention of the present embodiment, as described above, the slit 15b is provided in the blocking portion mounting plate 15 to reduce the impact force at the time of loading. FIG. 5 is a view for explaining the action of the slit 15b provided in the blocking portion mounting plate 15, and is a view of FIG. As shown in the figure, by providing the slit 15 b, the blocking portion mounting plate 15 is cantilevered on the insulating wall 13 of the insulating frame 12. When an impact load is generated by the charging operation and this load is applied to the blocking portion mounting plate 15, the blocking portion mounting plate 15 is bent and deformed as indicated by a dotted line in the figure. By utilizing this deformation, the impact energy at the time of charging is absorbed.

  When the fixed side terminal 2 is attached to the blocking part mounting plate 15 using the slit 15b, the blocking part mounting plate 15 is bent as shown by the dotted line in FIG. In this case, the impact load can be absorbed also by the frictional force generated when the contact portion between the washer 19 and the blocking portion mounting plate 15 is slightly shifted in the lateral direction.

  In addition, the fixing method of the fixed side terminal 2 and the interruption | blocking part attachment plate 15 is fixed to each support plate of a cantilever support state depending on the magnitude | size of the fixed side terminal 2 other than using a slit part as mentioned above. You may make it fix the side terminal 2 with a volt | bolt.

  Further, the opening 15a provided in the blocking portion mounting plate 15 is not a through hole, but is opened widely on the opposite side of the open end side, for example, as shown in FIG. It is good also as a shape where each cantilever is supported.

  Furthermore, the lead-out direction of the fixed-side terminal 2 is a through-hole provided in the insulating wall 13 on the opposite side to the open end, for example, as shown in FIG. 7, in addition to leading from the center side of the vacuum valve 1 to the open end side. 13a may be led out.

  As described above, according to the invention of Embodiment 1, at least the fixed-side terminal and the fixed-side conductor attached to the blocking-part mounting plate in the vicinity of the central part of the blocking-part mounting plate to which the vacuum valve is attached via the fixed-side terminal. An opening with a size that does not interfere with the connecting parts with the slit, and a slit from the opening toward the open end of the shut-off unit storage chamber, reduces the impact load when throwing in and contacts the vacuum valve It is possible to suppress chattering from occurring in the part. Therefore, it is possible to prevent a contact from being roughened, prevent a decrease in withstand voltage performance, and provide a highly reliable vacuum circuit breaker.

  In addition, since the fixed terminal is attached to the slit part of the blocking part mounting plate with a washer and a bolt, the contact part between the washer and the blocking part mounting plate is not bent when the blocking part mounting plate is bent by the impact load at the time of application. The impact force mitigating action can be further enhanced by the frictional force generated when it slightly deviates in the lateral direction.

  The present invention can be widely applied to open / close devices configured to support and fix a blocking portion to a blocking portion mounting member provided at one end of an insulating frame that houses the blocking portion.

It is a top view of the vacuum circuit breaker by Embodiment 1 of this invention. It is side surface sectional drawing seen from II-II of FIG. It is a perspective view which shows the three-phase insulation frame of the vacuum circuit breaker by Embodiment 1 of this invention. It is the elements on larger scale which show the interruption | blocking part attachment plate provided in the insulation frame of the vacuum circuit breaker by Embodiment 1 of this invention. It is a figure explaining the effect | action of the interruption | blocking part attachment plate of the insulation frame of the vacuum circuit breaker by Embodiment 1 of this invention. It is a figure which shows another example of the interruption | blocking part attachment plate of the vacuum circuit breaker by Embodiment 1 of this invention. It is a figure which shows another example of the fixed terminal attachment part of the vacuum circuit breaker by Embodiment 1 of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Vacuum valve 1d Fixed side conductor 1e Movable side conductor 2 Fixed side terminal 4 Movable side terminal 5 Insulating operation member 12 Insulating frame 13 Insulating wall 14 Blocking part accommodation chamber 15 Blocking part mounting plate 15a Opening part 15b Slit 19 Washer 20 Fixed bolt

Claims (1)

A blocking part accommodation chamber is formed around the reference axis line, with a part left as an open end and the other part surrounded by an insulating wall in a substantially U-shape, on one end side in the axial direction of the blocking part accommodation chamber An insulating frame provided with a blocking portion mounting plate in the vicinity of the end portion and perpendicular to the axis;
A fixed-side terminal provided so as to protrude perpendicularly to the axis and to the open end side of the blocking portion accommodation chamber or the opposite side thereof;
A cylindrical vacuum valve disposed on the axis of the shut-off portion accommodating chamber in alignment with the axis, with a fixed conductor led out from one end and a movable terminal led out from the other end;
In the vacuum circuit breaker in which the fixed side conductor of the vacuum valve is attached to the fixed side terminal, and the fixed side terminal is fixed to the blocking portion mounting plate so that the vacuum valve is supported and fixed to the insulating frame.
The blocking portion mounting plate is provided with an opening having a size that does not interfere with at least the connection parts of the fixed-side terminal and the fixed-side conductor at a portion orthogonal to the axis, and from the opening to the above-mentioned A slit is formed toward the open end,
The fixed side terminal has a facing portion facing the slit, and is fastened and fixed by a bolt penetrating the slit through a washer at a position of the slit of the blocking portion mounting plate. Vacuum circuit breaker.

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