JP6753177B2 - Switch - Google Patents

Description

The present invention relates to a switch having a mechanical puffer mechanism.

Conventionally, in switches such as disconnectors and grounding switches, as disclosed in Patent Document 1, for example, as the movable contactor operates when the path is opened, insulating gas is sucked from the vicinity of the arc generation location to extinguish the arc. Some are equipped with a mechanical puffer mechanism that obtains an arc action. This puffer mechanism has a cylinder structure that expands the volume of the puffer chamber by the operation of a movable contactor.

However, the operating load of the movable contact during the above-mentioned opening operation is not only related to the simple backward operation, but also the suction operation of the insulating gas due to the expansion of the volume of the puffer chamber is added, so that the movable contact is operated. A large load is applied to the operating device. Therefore, it is necessary to take measures such as using a large operating device that generates a large operating force.

Therefore, in the technique disclosed in Patent Document 1, an auxiliary mechanism for reducing the operating load of the movable contactor is added to the puffer mechanism. This auxiliary mechanism has a configuration in which a through hole is provided in a movable plate (piston in the literature) that operates integrally with the movable contactor, and a closing plate (auxiliary piston in the literature) is further moved with respect to the movable plate. Then, at the initial stage of the opening operation of the movable contactor, the closing plate is separated from the movable plate to open the through hole, thereby alleviating a large negative pressure in the puffer chamber and reducing the operating load of the movable contactor. It is to be alleviated.

Jikkenhei No. 5-6622

In a switch capable of reducing the operating load of the movable contactor, the present inventor has been studying whether further reduction can be achieved. Of course, it is also important not to adversely affect the suction operation (puffer operation) of the insulating gas for extinguishing the arc.

An object of the present invention is to provide a switch with a mechanical puffer mechanism capable of improving the arc extinguishing action of an arc while further reducing the operating load of the movable contactor.

A switch that solves the above problems switches the electric circuit from closed to open by retracting the movable contacts from the fixed contacts and separating the movable contacts from the fixed contacts that are in contact with each other. It is a device, and a movable plate linked with the retracting operation of the movable contact is used to expand the volume of the puffer chamber arranged side by side on the movable contact side, and the inside passage of the movable contact is opened through the tip opening of the movable contact. A switch having a mechanical puffer mechanism that sucks an insulating gas into the puffer chamber and extinguishes an arc generated at the tip of the movable contact, and retracts the movable contact. In the process, the period from the fixed contact to the time when the movable contact is separated is defined as the initial stage of the opening operation, the subsequent period is defined as the middle stage of the opening operation and the latter stage of the opening operation, and the puffer chamber is opened at the initial stage of the opening operation. The first opening means and the second opening means for opening the puffer chamber in the latter stage of the opening operation are provided, and the puffer operation is performed in the middle of the opening operation in which the opening means do not function to extinguish the arc. It is configured as follows.

According to this configuration, in the process of retracting the movable contact, the path is opened until the movable contact is separated from the fixed contact (in this case, the separation time itself and a slight period before and after the separation time). At the initial stage of operation, the puffer chamber is opened by the first opening means. Further, the puffer chamber is opened again by the second opening means in the latter stage of the opening operation after the middle stage of the opening operation in which the puffer operation is performed. In other words, since an arc is generated immediately after the movable contact is separated from the fixed contact, efficient puffer operation is performed only in the middle of this opening operation when necessary, and in the other early and late stages of the opening operation, the puffer chambers are performed. Is released, and the operating load of the movable contactor is reduced.

Further, in the above switch, the first opening means includes the movable plate having a through hole and the closing plate for closing the through hole, and the closing plate is provided for a movable body including the movable contact. The movable plate is supported on the movable body so as to be in contact with and separated from the closing plate on the retracting side of the movable contact from the closing plate, and the movable corresponding to the initial stage of the opening operation is further supported. It is configured to have a regulating portion that regulates the movable plate so that the movable plate is separated from the closing plate within the position range of the contactor.

According to this configuration, a closing plate fixed to a movable body including a movable contactor and a movable plate supported by the movable body so as to be in contact with and detachable from the closing plate on the retracted side of the movable contactor rather than the closing plate. , The closing / opening of the through hole of the movable plate by the closing plate is switched in conjunction with the retracting operation of the movable body. Then, the movable plate is regulated by the regulating portion so as to be separated from the closing plate within the position range of the movable contactor corresponding to the initial stage of the opening operation, so that the through hole of the movable plate is opened at the initial stage of the opening operation. The puffer room is open. The opening means (first opening means) of the puffer chamber at the initial stage of such opening operation can be relatively easily configured by the closing plate, the movable plate and the regulating portion.

Further, the switch is provided with a movable side cylinder that forms the puffer chamber together with the insertion of the movable contactor, and the restricting portion is a step formed on the inner peripheral surface of the movable side cylinder.

According to this configuration, the regulating portion that regulates the arrangement position of the movable plate is composed of a step formed on the inner peripheral surface of the movable cylinder, so that an increase in the number of parts can be prevented and the configuration can be easily performed.
Further, in the above switch, the first opening means is provided with an urging spring that urges the movable plate toward the closing plate side.

According to this configuration, since an urging spring for urging the movable plate to the closing plate side is provided, the closing plate and the movable plate are surely brought into contact with each other when necessary, that is, the through hole of the movable plate is closed by the closing plate. It is possible to do it reliably.

Further, in the switch, the movable side cylinder that forms the puffer chamber together with the insertion of the movable contact is provided, and the second opening means is the position range of the movable contact corresponding to the latter stage of the opening operation. It is composed of an external communication hole that communicates the puffer chamber in the movable cylinder with the outside.

According to this configuration, the puffer chamber in the movable cylinder communicates with the outside through the external communication hole in the position range of the movable contact corresponding to the latter stage of the opening operation. The opening means (second opening means) of the puffer chamber in the latter stage of the opening operation can be easily configured by a hole such as a communication hole, and an increase in the number of parts can be prevented.

Further, in the above switch, the fixed contact includes a first fixed contact and a second fixed contact, and the first fixed contact is brought into contact by fitting the outer peripheral portion of the tip of the movable contact. The second fixed contact is in contact with the movable contact on the tip surface, and the second fixed contact is provided by receiving an urging force on the movable contact side by an urging spring.

According to this configuration, the fixed contacts have first and second fixed contacts, the first fixed contact is brought into contact by fitting the outer peripheral portion of the tip of the movable contact, while the second fixed contact is The movable contactor and the tip surface come into contact with each other. The second fixed contact is provided by receiving an urging force on the movable contact side by the urging spring. As a result, the urging force received by the second fixed contact contributes to reducing the operating load during the retracting operation of the movable contact, and particularly contributes to accelerating the initial speed of the retracting operation of the movable contact.

According to the switch with the mechanical puffer mechanism of the present invention, it is possible to improve the arc extinguishing action while further reducing the operating load of the movable contactor.

The cross-sectional view which shows the closed state of the switch in one Embodiment. The cross-sectional view which shows the state during operation of the switch of the same form. The cross-sectional view which shows the state during operation of the switch of the same form. The cross-sectional view which shows the state during operation of the switch of the same form. The cross-sectional view which shows the state during operation of the switch of the same form. The cross-sectional view which shows the opening state of the switch of the same form.

Hereinafter, an embodiment of the switch will be described.
The switch 10 of the present embodiment shown in FIG. 1 is installed in a container (not shown) in which an insulating gas (SF ₆ gas or the like) is housed, that is, in an insulating gas atmosphere. The switch 10 includes a fixed contact side unit 11 and a movable contact side unit 21.

In the fixed contact side unit 11, the base end portion of the tubular support base 13 is fixed to the fixed side conductor 12 as the base portion on the surface facing the movable contact side unit 21, and the outer peripheral portion of the tip of the tubular support base 13 is fixed. The first fixed contactor 14 is fixed to the. The tubular support base 13 and the first fixed contact 14 are conductors like the fixed side conductor 12, and the fixed side conductor 12, the tubular support 13 and the first fixed contact 14 are electrically connected to each other. ..

The first fixed contact 14 has a substantially cylindrical shape, and the inner diameter of the contact portion 14a at the inner peripheral portion of the tip is set to be slightly smaller than the outer diameter of the movable contact 23 described later, and in the diameter reduction direction. It has an elastic force. That is, the contact portion 14a is capable of electrical contact so that a desired contact pressure can be obtained with respect to the movable contact 23 by fitting the movable contact 23. The inner diameter of the tubular support 13 is outside the movable contact 23 so that the inner peripheral surface of the tubular support 13 does not come into contact with the movable contact 23 when the movable contact 23 is fitted into the contact portion 14a. The setting is slightly larger than the diameter.

One accommodating recess 15 is formed straddling both the inner portion 13a of the tubular support 13 and the concave portion 12a provided on the fixed side conductor 12, and the second fixed contact 16 is accommodated in the accommodating recess 15. Has been done. The second fixed contact 16 is made of a conductor and has a substantially cylindrical shape. The second fixed contact 16 is operably housed in the housing recess 15 coaxially with the movable contact 23, and the inner housing portion 16a of the second fixed contact 16 and the concave portion 12a of the fixed side conductor 12 are accommodated. An urging spring 17 provided between them obtains an urging force toward the movable contact 23 side.

That is, in the state of FIG. 1 in which the movable contact 23 protrudes most, the second fixed contact 16 is arranged at the position most pushed by the movable contact 23 against the urging force of the urging spring 17. It is in a state of being immersed further than the contact portion 14a of the first fixed contactor 14. Further, in this case, the movable contact 23 has its own outer peripheral portion in contact with the contact portion 14a of the first fixed contact 14, and the tip surface 23a of the movable contact 23 is the tip of the second fixed contact 16. It is in contact with the surface 16b, and an electrical connection is established between the two. The first fixed contact 14 is a main contact, while the second fixed contact 16 is an auxiliary contact for arc cutting.

Further, the second fixed contact 16 has a locking protrusion 16d that protrudes outward in the radial direction on the outer peripheral surface of the base end of the main body portion 16c. Correspondingly, the tubular support base 13 has a step (hereinafter, the regulation step portion 13b) protruding inward in the radial direction on the inner peripheral surface of the tip. The outer diameter of the main body 16c of the second fixed contact 16c is set to be slightly smaller than the inner diameter of the regulation step portion 13b of the tubular support 13 and the inner diameter of the contact portion 14a of the first fixed contact 14. It is designed so that it does not come into contact with the second fixed contact 16 during operation. On the other hand, in the second fixed contact 16, the outer diameter of the tip portion (radial outer end portion) of the locking protrusion 16d is larger than the inner diameter of the radial inner end portion of the regulation step portion 13b of the tubular support base 13. The setting is also large, and the locking protrusion 16d and the regulation step portion 13b can be locked in the protruding direction of the second fixed contact 16.

That is, in the process of retracting the movable contact 23 to the state shown in FIGS. 1 to 6, the second fixed contact 16 is moved by the urging force of the urging spring 17 as the movable contact 23 retracts. When it protrudes while maintaining the contact state with 23 and its own locking protrusion 16d is locked to the regulation step portion 13b of the tubular support base 13, the most protruding position where the operation to the protruding side is further restricted. (See FIGS. 3 to 6). When the second fixed contact 16 is arranged at the most protruding position, its tip portion protrudes from the first fixed contact 14 (contact portion 14a).

Further, in the second fixed contact 16, the outer diameter of the tip portion (diameter outer end portion) of the locking protrusion 16d is set to be substantially equal to the inner diameter of the main body portion of the tubular support base 13. When the second fixed contact 16 operates in the accommodating recess 15, the locking protrusion 16d is in contact with the inner peripheral surface of the tubular support base 13 and the inner peripheral surface of the concave portion 12a of the fixed side conductor 12. Is maintained.

On the outer peripheral side of the first fixed contact 14 and the like, a substantially hemispherical shield member 18 that completely covers the first fixed contact 14 and the like is assembled to the fixed conductor 12. The shield member 18 has an opening 18a into which the movable contact 23 is inserted, and when the second fixed contact 16 is arranged at the most protruding position (see FIG. 3 and the like), the tip surface of the second fixed contact 16 is formed. The 16b and the opening 18a are substantially flush with each other.

In the movable contact side unit 21, the movable side cylinder 22 as a base is made of a conductor, and has a hollow substantially cylindrical shape in which the side facing the fixed contact side unit 11 is closed by a closing wall 22a. The movable cylinder 22 is immovable, and the distance from the fixed contact side unit 11 is constant. A support cylinder portion 22b is formed in the central portion of the closing wall 22a of the movable cylinder 22 so as to project substantially in a cylindrical shape toward the fixed contact side unit 11. The inner peripheral portion of the support cylinder portion 22b operably supports the movable contact 23 in the axial direction. The movable contact 23 is made of a conductor and has an elongated cylindrical shape.

A sliding contactor 24 is fixed to the outer peripheral portion of the tip of the support cylinder portion 22b. The sliding contact 24 is made of a conductor and is electrically connected to the movable cylinder 22. The sliding contact 24 has a substantially cylindrical shape, and the inner diameter of the contact portion 24a at the inner peripheral portion of the tip is set to be slightly smaller than the outer diameter of the movable contact 23, and an elastic force is applied in the diameter reduction direction. It is a structure to have. That is, the contact portion 24a is capable of electrical contact so that a desired contact pressure can be obtained with respect to the movable contact 23 even if the movable contact 23 operates in the axial direction.

On the outer peripheral side of the sliding contactor 24, a substantially hemispherical shield member 25 that covers the sliding contactor 24 and the like as a whole is assembled to the movable cylinder 22. The shield member 25 has an opening 25a through which the movable contact 23 is inserted, and the tip end side of the movable contact 23 projects from the opening 25a toward the fixed contact side unit 11.

An operating rod 26 for operating the movable contact 23 is coaxially fixed to the base end portion of the movable contact 23. A substantially disc-shaped closing plate 27 is fixed to the boundary portion between the movable contact 23 and the operation rod 26. As will be described later, the closing plate 27 closes the through hole 28a provided in the movable plate 28 when it comes into contact with the movable plate 28, and closes the through hole 28a of the movable plate 28 when it is separated from the movable plate 28. It works to open. A plurality of through holes 28a are provided in the movable plate 28 in the circumferential direction of the movable plate 28 so as to penetrate the front and back sides at a portion inside the outer peripheral edge of the closing plate 27 (only two are shown in FIG. 1 and the like).

A substantially disk-shaped movable plate 28 is inserted on the base end side (opposite side of the movable contact 23) of the operating rod 26 from the closing plate 27, and the operation can be relatively moved in the axial direction of the operating rod 26. It is supported against the rod 26. A seal member 29 is attached to the movable plate 28 over the entire circumference of the outer peripheral surface, and the seal member 29 can move along the axial direction while being in contact with the inner peripheral surface of the movable cylinder 22. There is. The movable plate 28 makes the volume of the puffer chamber 30 formed between the movable plate 28 and the closing wall 22a of the movable cylinder 22 variable by its own operation.

Further, a coil-shaped urging spring 31 is inserted through the base end side of the operating rod 26 with respect to the movable plate 28, and a receiving member 32 is further attached to the base end side. The movable plate 28 receives the urging force of the urging spring 31 toward the closing plate 27 with the receiving member 32 as a base point. If the movable plate 28 is not regulated by the regulation step portion 22c provided on the inner peripheral surface of the movable cylinder 22, the movable plate 28 receives the urging force of the urging spring 31 and maintains the contact state with the closing plate 27. That is, the closed state of the through hole 28a of the movable plate 28 is maintained by the closing plate 27. On the other hand, when the movable plate 28 is regulated by the regulation step portion 22c and relatively separated from the closing plate 27, the through hole 28a of the movable plate 28 is opened, and the puffer chamber 30 is opened.

Here, the movable contact 23 has an inner space formed along the axial direction as an inner passage 23b by forming a cylindrical shape. The inner passage 23b has a tip opening 23c that opens on one side at the tip surface 23a of the movable contact 23, and a proximal opening 23d that opens into the puffer chamber 30 on the outer periphery of the proximal end of the movable contact 23 on the other side. have. A plurality of base end openings 23d are provided in the circumferential direction of the base end outer peripheral portion of the movable contact 23 (only one is shown in FIG. 1 and the like). The base end opening 23d is always opened in the puffer chamber 30 regardless of the position in the operating range of the movable contact 23. Then, when the through hole 28a is closed by the closing plate 27 and the puffer chamber 30 is not communicating with the external communication hole 22d, the volume expansion operation of the puffer chamber 30 by the movable plate 28 is performed (FIG. 2, etc.). (See), the insulating gas is sucked into the puffer chamber 30 from the tip opening 23c of the movable contact 23. That is, these constitute a mechanical puffer mechanism.

A regulation step portion 22c protruding inward in the radial direction is formed on the inner peripheral surface of the movable cylinder 22. The regulation step portion 22c is closed at the tip end side (movable side cylinder 22) of the movable contact side unit 21 at a predetermined front position (position in FIG. 2) at the position shown in FIG. 1 where the movable contact 23 and the operating rod 26 are most projected. It is locked with the movable plate 28 toward the wall 22a), and further movement of the movable plate 28 is restricted. That is, the regulation step portion 22c defines the operating range of the movable plate 28 that operates in conjunction with the movable contact 23 and the operating rod 26.

Further, on the inner peripheral surface of the movable cylinder 22, the inside and outside of the peripheral wall of the movable cylinder 22 are placed at a predetermined position on the base end side (the side separated from the closing wall 22a of the movable cylinder 22) from the regulation step portion 22c. An external communication hole 22d for communication is formed. The external communication holes 22d are slit-shaped holes, and a plurality of external communication holes 22d are provided in the circumferential direction of the peripheral wall of the movable cylinder 22 (only two are shown in FIG. 1 and the like). The external communication hole 22d communicates the puffer chamber 30 with the external space of the movable cylinder 22 at a predetermined front position (slightly retracted position side in FIG. 5) of the position shown in FIG. 6 where the movable contact 23 and the operating rod 26 are most retracted. The puffer chamber 30 is opened.

Next, the operation (action) of the switch 10 of the present embodiment will be described.
[Opening operation]
The opening operation of the switch 10 is an operation from the closing state shown in FIG. 1 to the opening state shown in FIG. 6 through the intermediate states of FIGS. 2 to 5. Incidentally, the time required for the opening operation of the switch 10 is about several cycles to a dozen cycles of commercial alternating current that the switch 10 opens and closes.

First, in the closed circuit state shown in FIG. 1 of the switch 10, the movable contact 23 is arranged at the most protruding position, the tip of the movable contact 23 is fitted into the first fixed contact 14, and the outer peripheral portion of the tip is in contact. It is in a pressure contact state with the portion 14a. Further, the tip of the movable contact 23 is in a state in which the second fixed contact 16 is pushed most, and the tip surfaces 23a and 16b of each other are in a pressure contact state. As a result, the movable contact 23 is in a conductive state with the first and second fixed contacts 14 and 16, and the fixed side conductor 12 and the movable cylinder 22 are in a conductive state, that is, the electric circuits before and after the switch 10 are closed. It has become.

Then, in order to switch the switch 10 to the open path state, the operation rod 26 is operated by the operation mechanism (not shown), and the movable contact 23 retracts. In the fixed contact side unit 11, since the second fixed contact 16 receives the urging force toward the movable contact 23 side by the urging spring 17, both tip surfaces 23a and 16b are retracted as the movable contact 23 retracts. Performs a protruding operation while maintaining contact with each other. In the movable contact side unit 21, the closing plate 27 in the separated state approaches the movable plate 28 as the movable contact 23 retracts (the through hole 28a of the movable plate 28 is in the open state). Further, the movable plate 28 receives the urging force of the urging spring 31 and is held in a contact state with the regulation step portion 22c of the movable cylinder 22.

When the movable contact 23 retracts to the state shown in FIG. 2, the closing plate 27 abuts on the movable plate 28, and the closing plate 27 closes the through hole 28a of the movable plate 28. The state from the state of FIG. 1 to the state of FIG. 2 is the initial opening operation of the switch 10 (initial of the retracting operation of the movable contact 23) X1. After that (next mid-term of opening operation X2), the movable plate 28 performs the volume expansion operation of the puffer chamber 30 together with the retracting operation of the movable contact 23, but the through hole 28a of the movable plate 28 is closed. Therefore, an operation of sucking the insulating gas from the tip opening 23c via the inner passage 23b of the movable contact 23 (puffer operation) is performed. That is, in the subsequent operations, the operating load of the movable contact 23 increases with the puffer operation, and the operating force of the operating rod 26 increases. In other words, in the initial opening operation X1 up to the state of FIG. 2, the operating load of the movable contact 23 is reduced by the amount that the puffer operation is not performed.

On the other hand, similarly, in the initial opening operation X1, the tip portion of the movable contact 23 comes out of the first fixed contact 14 (contact portion 14a), and the continuity with the first fixed contact 14 side is released. That is, since the contact portion 14a of the first fixed contact 14 is in pressure contact with the movable contact 23, the sliding resistance when the movable contact 23 is pulled out increases the operating load. Further, although the movable contact 23 is released from the conduction with the first fixed contact 14, the conductive state is maintained with respect to the second fixed contact 16 protruding following the retracting operation of the movable contact 23. To. That is, in the initial opening operation X1, the arc A (see FIG. 4) does not occur between the movable contact 23 and the first fixed contact 14, so that the puffer operation is unnecessary.

Based on this, in the initial opening operation X1, although sliding resistance occurs when the movable contact 23 is pulled out from the first fixed contact 14, the puffer operation is not performed at the same time, and the operating load of the movable contact 23 is prevented. Is being reduced. Since the urging forces of both urging springs 17 and 31 assist the retracting operation of the movable contact 23, it contributes to the reduction of the operating load of the movable contact 23.

Next, when the movable contact 23 retracts from the state shown in FIG. 2, the closing plate 27 closes the through hole 28a of the movable plate 28 and presses the movable plate 28 with the closing plate 27 (the urging force of the urging spring 31). The movable plate 28 is also urged toward the closing plate 27), and the movable plate 28 interlocks with the retracting operation of the movable contact 23 to expand the volume of the puffer chamber 30. As a result, the operation of sucking the insulating gas from the tip opening 23c of the movable contact 23 into the puffer chamber 30 via the inner passage 23b (puffer operation) is performed. The period of FIGS. 2 to 5 in which this puffer operation is performed is the middle stage of the opening operation of the switch 10 (the middle stage of the retracting operation of the movable contactor 23) X2.

In the state of FIG. 3, the tip of the second fixed contact 16 protrudes from the first fixed contact 14, and the locking protrusion 16d of the second fixed contact 16 engages with the regulation step portion 13b of the tubular support base 13. It is in a state where the second fixed contact 16 is stopped and the further protruding operation of the second fixed contact 16 is restricted. After that, the tip surface 23a of the movable contact 23 begins to separate from the tip surface 16b of the second fixed contact 16, and an arc A (see FIG. 4) is generated between the two tip surfaces 16b and 23a. Based on this, the puffer operation is started from the state of FIG. 2 shortly before the state of FIG. 3, that is, the suction operation of the insulating gas is started from the tip opening 23c of the movable contact 23, and the arc A is extinguished. Prepare for. The insulating gas sucked from the tip opening 23c of the movable contact 23 enters through the gaps between the two tip surfaces 16b and 23a in contact with each other, the second fixed contact 16 and the tubular support base 13.

The state of FIG. 4 is a state in which the tip surface 23a of the movable contact 23 is slightly separated from the tip surface 16b of the second fixed contact 16 and an arc A is generated between the two tip surfaces 16b and 23a. Since the second fixed contact 16 is an auxiliary contact for arc cutting, it separates from the movable contact 23 later than the first fixed contact 14 which is the main contact. In the state of FIG. 4, since the insulating gas is sucked into the puffer chamber 30 by the operation of the movable plate 28 linked with the retracting operation of the movable contact 23, the tip opening 23c of the movable contact 23 is surrounded by the surroundings. The insulating gas is vigorously sucked in, and the air flow of the insulating gas toward the tip opening 23c extinguishes the arc A.

In the state of FIG. 5, the retracting operation of the movable contact 23 has progressed, and the movable plate 28 has reached the external communication hole 22d of the movable cylinder 22. After that (the next opening operation late X3), the movable plate 28 exceeds the position where the external communication hole 22d is provided, and the puffer chamber 30 communicates with the outside of the movable cylinder 22 via the external communication hole 22d. Even if the volume expansion operation of the puffer chamber 30 is performed by the movable plate 28, the suction of the insulating gas (puffer operation) is not performed. In other words, the arc A is extinguished by the puffer operation in the middle stage X2 of the opening operation up to the state of FIGS. 2 to 5, in this case, in a period of about 1 to 2 cycles of commercial alternating current.

Then, when the movable contact 23 retracts from the state shown in FIG. 5, the movable plate 28 interlocking with the movable contact 23 exceeds the position of the external communication hole 22d of the movable cylinder 22, and the puffer chamber 30 passes through the external communication hole 22d. It communicates with the outside of the movable cylinder 22. The period including FIG. 6 in which the puffer operation is released is the latter stage of the opening operation of the switch 10 (the latter stage of the retracting operation of the movable contact 23) X3.

In the late opening operation X3, the movable contact 23 is sufficiently separated from the second fixed contact 16 to prevent the arc A from being generated, so that the puffer operation becomes unnecessary. Based on this, by opening the puffer chamber 30 through the external communication hole 22d, the operating load of the movable contact 23 is reduced, and the operating force of the operating rod 26 is reduced.

As described above, the switch 10 of the present embodiment performs the puffer operation only in the middle stage X2 of the opening operation that requires the puffer operation, and does not perform the puffer operation in the initial X1 and the late X3 of the opening operation that do not require the puffer operation. In this way, the operating load of the movable contact 23 is reduced.

[Closed operation]
The closing operation of the switch 10 is an operation from the opening state shown in FIG. 6 to the closing state shown in FIG. The closing operation operates in the reverse order of the above description of the opening operation, that is, in the order of the late opening operation X3, the middle X2, and the initial X1.

In the initial stage of the closing operation of the switch 10 (late opening operation X3), even if the movable contact 23 protrudes, the puffer chamber 30 is opened through the external communication hole 22d of the movable cylinder 22 and the puffer operation is not performed. , The operating load at the initial stage of the protruding operation of the movable contact 23 is reduced.

Next, in the middle stage of the closing operation of the switch 10 (mid-term X2 of the late opening operation), the puffer operation is performed along with the protruding operation of the movable contact 23, so that the operating load in the middle stage of the protruding operation of the movable contact 23 is higher than the initial stage. To do. If the urging spring 31 or the like is set so that the movable plate 28 is relatively separated from the closing plate 27 that operates integrally with the movable contact 23 by the projecting operation of the movable contact 23, the closing path is set. The puffer operation can be prevented even in the middle stage of operation, and the operating load of the movable contact 23 can be reduced.

Then, in the latter stage of the closing operation of the switch 10 (initial opening operation X1), the operating load of the movable contact 23 increases by the amount of fitting into the first fixed contact 14 and pushing operation of the second fixed contact 16. However, since the puffer chamber 30 is opened through the through hole 28a of the movable plate 28 and the puffer operation is not performed, the operation load of the movable contact 23 in the latter stage of the protruding operation is reduced. As described above, even in the closing operation of the switch 10 of the present embodiment, the operating load of the movable contact 23 is preferably reduced.

Next, the characteristic effects of this embodiment will be described.
(1) In the opening operation process of the switch 10 (retracting operation process of the movable contact 23), the puffer chamber 30 closes at the initial X1 of the opening operation from the second fixed contact 16 to just before the movable contact 23 separates. 27, the movable plate 28 and the regulation step portion 22c work to open the open state. Further, in the late opening operation X3 after the middle opening operation X2 in which the puffer operation is performed, the puffer chamber 30 is opened again by the action of the external communication hole 22d. That is, since the arc A is generated immediately after the movable contact 23 is separated from the second fixed contact 16, the efficient puffer operation limited to this mid-term X2 of the opening operation when necessary is performed, and the other opening operations are performed. In the initial X1 and the late X3, the operating load of the movable contact 23 can be reduced by opening the puffer chamber 30, respectively. This contributes to the miniaturization of the operation mechanism (not shown) for operating the movable contact 23 (operation rod 26). Further, if the operating force of the movable contact 23 (operating rod 26) can be reduced, the inner diameter of the movable cylinder 22 can be expanded and the puffer chamber 30 can be expanded, so that a powerful puffer operation (suction operation) can be performed in a short time. It is possible to have a possible cylinder structure, and it is possible to further improve the arc extinguishing performance.

(2) A closing plate 27 fixed to an operating rod 26 (which constitutes a movable body) coaxially connected to the movable contact 23, and a closing plate 27 on the retracted side of the movable contact 23 from the closing plate 27. The movable plate 28, which is detachably supported by the operating rod 26, switches the closing / opening of the through hole 28a of the movable plate 28 by the closing plate 27 in conjunction with the retracting operation of the movable contact 23 (operating rod 26). Be done. Then, the movable plate 28 is regulated by the regulation step portion 22c so as to be separated from the closing plate 27 in the position range of the movable contact 23 corresponding to the opening operation initial X1, so that the movable plate 28 is regulated in the opening operation initial X1. The through hole 28a of 28 is opened, and the puffer chamber 30 is opened. The opening means (first opening means) of the puffer chamber 30 in such an initial opening operation X1 can be relatively easily configured by the closing plate 27, the movable plate 28, and the regulation step portion 22c.

(3) Since the regulating portion that regulates the arrangement position of the movable plate 28 is composed of the regulating step portion 22c formed on the inner peripheral surface of the movable cylinder 22, it is possible to prevent an increase in the number of parts and it can be easily configured. ..

(4) Since the urging spring 31 for urging the movable plate 28 to the closing plate 27 side is provided, the closing plate 27 and the movable plate 28 are surely brought into contact with each other when necessary, that is, the movable plate 28 is penetrated by the closing plate 27. The hole 28a can be reliably closed.

(5) The puffer chamber 30 in the movable cylinder 22 communicates with the outside through the external communication hole 22d within the position range of the movable contact 23 corresponding to the late opening operation X3. The opening means (second opening means) of the puffer chamber 30 in such a late opening operation X3 can be easily configured by a hole such as the communication hole 22d, and an increase in the number of parts can be prevented.

(6) It has first and second fixed contacts 14 and 16 as fixed contacts, and the first fixed contact 14 comes into contact by fitting the outer peripheral portion of the tip of the movable contact 23, whereas the second fixed contact The child 16 comes into contact with the movable contact 23 and the tip surfaces 16b and 23a. The second fixed contact 16 is provided by receiving an urging force on the movable contact 23 side by the urging spring 17. As a result, the urging force received by the second fixed contact 16 can contribute to reducing the operating load during the retracting operation of the movable contact 23, and particularly contributes to accelerating the initial speed of the retracting operation of the movable contact 23. it can.

The above embodiment may be changed as follows.
-It was set to start the puffer operation as the middle stage X2 of the opening operation from slightly before the movable contact 23 is separated from the second fixed contact 16 (after the state of FIG. 2), but the movable contact is started from the second fixed contact 16. The puffer operation may be started when the 23 is separated (the state of FIG. 3) or when the movable contact 23 is slightly separated (for example, the state of FIG. 4).

-In the above embodiment, the fixed contact is composed of two contacts (first and second fixed contacts 14, 16), but is composed of only the first fixed contact 14 which is the main contact. May be good. In this case, the urging spring 17 can be omitted together with the second fixed contact 16, which also contributes to the miniaturization of the fixed contact.

-In the above embodiment, the closing plate 27, the movable plate 28, and the like are assembled to the operation rod 26, but the structure may be such that they are attached to the movable contact 23.
In the above embodiment, the retracting operation of the movable contact 23 is transmitted to the movable plate 28 via the closing plate 27, but a locking portion having no function of closing the through hole 28a of the movable plate 28 is transmitted to the movable contact 23. The movable plate 28 may be integrally provided and the movable plate 28 may be interlocked with the movable contact 23 at the locking portion thereof.

-In the above embodiment, the closing plate 27 has a plate shape, but it may be configured in any other shape.
-In the above embodiment, the urging spring 31 that urges the movable plate 28 toward the closing plate 27 is used, but the urging spring 31 may be omitted.

-In the above embodiment, the position of the movable plate 28 is regulated by a step (regulation step portion 22c) integrally formed on the inner peripheral surface of the movable cylinder 22, but the regulation portion may be configured by another member.
-In addition to the above alternative example, the configuration of the switch 10 may be changed as appropriate.

14 ... 1st fixed contact (fixed contact), 16 ... 2nd fixed contact (fixed contact), 16b ... tip surface, 17 ... urging spring (2nd fixed contact urging), 22 ... movable Side cylinder, 22c ... Regulatory step portion (first opening means, regulating portion, step), 22d ... External communication hole (second opening means), 23 ... Movable contactor (movable body), 23a ... Tip surface, 23b ... Internal Passage, 23c ... Tip opening, 26 ... Operating rod (movable body), 27 ... Closing plate (first opening means), 28 ... Movable plate (first opening means), 28a ... Through hole, 30 ... Puffer chamber, 31 ... Biasing spring (first opening means), A ... Arc, X1 ... Early opening operation, X2 ... Middle opening operation, X3 ... Late opening operation.

Claims (5)

A switch for switching an electric circuit from a closed circuit to an open circuit by retracting the movable contact from the fixed contact and separating the movable contact from the fixed contacts that are in contact with each other. The movable plate linked with the retracting operation causes the volume expansion operation of the puffer chamber arranged side by side on the movable contact side, and the insulating gas is sent from the tip opening of the movable contact to the puffer chamber via its own inner passage. A switch having a mechanical puffer mechanism that performs a puffer operation to suck in and extinguish the arc generated at the tip of the movable contact.
In the retracting operation process of the movable contact, the period from the fixed contact to the time when the movable contact is separated is defined as the initial stage of the opening operation, and the subsequent periods are defined as the middle stage of the opening operation and the latter stage of the opening operation. A first opening means for opening the puffer chamber and a second opening means for opening the puffer chamber in the latter stage of the opening operation are provided, and the puffer operation is performed in the middle of the opening operation in which each opening means does not function. It is configured to extinguish the arc .
The first opening means includes the movable plate having a through hole and a closing plate that closes the through hole, fixes the closing plate to a movable body including the movable contact, and closes the closing plate. The movable plate is supported on the movable body so as to be in contact with and separated from the closing plate on the retracted side of the movable contact, and the movable plate is movable within the position range of the movable contact corresponding to the initial stage of the opening operation. A switch characterized by having a regulating portion that regulates the movable plate so that the plate is separated from the closing plate . In the switch according to claim 1 ,
A movable side cylinder that forms the puffer chamber together with the insertion of the movable contact is provided.
The switch is a switch characterized by a step formed on the inner peripheral surface of the movable cylinder. In the switch according to claim 1 or 2 ,
The first opening means is a switch provided with an urging spring for urging the movable plate toward the closing plate side. In the switch according to any one of claims 1 to 3 , the switch
A movable side cylinder that forms the puffer chamber together with the insertion of the movable contact is provided.
The second opening means is characterized by being composed of an external communication hole for communicating the puffer chamber in the movable cylinder with the outside in the position range of the movable contact corresponding to the latter stage of the opening operation. Switch. In the switch according to any one of claims 1 to 4 , the switch
The fixed contact includes a first fixed contact and a second fixed contact, the first fixed contact is brought into contact by fitting the outer peripheral portion of the tip of the movable contact, and the second fixed contact is said. The movable contactor and the tip surface come into contact with each other,
The second fixed contact is a switch provided by receiving an urging force on the movable contact side by an urging spring.

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