Switch

Abstract

By interposing a second switch between a vacuum switch and a first switch, and electrically connecting the second switch and the vacuum switch in parallel, a switch that can meet the demand for miniaturization is provided. [Solution] The device comprises a vacuum switch 2 having a vacuum electrode 2E that can be opened and closed in a vacuum atmosphere, a first switch 3 having a first electrode 3E that can be opened and closed in an insulating atmosphere other than a vacuum, and a second switch 4 interposed between the vacuum switch and the first switch and having a second electrode 4E that can be opened and closed in an insulating atmosphere other than a vacuum. The first switch is electrically connected in series with the vacuum switch, and the second switch is electrically connected in parallel with the vacuum switch and also electrically connected in series with the first switch.

Description

Technical Field

[0001] Embodiments of this invention relate to a switchgear.

Background Art

[0002] As a switchgear for power reception and distribution provided in buildings and large facilities, a switchgear equipped with various switchgears such as a circuit breaker, a disconnector, and a grounding device is known. In the switchgear, as components of these various switchgears, for example, a vacuum switchgear (also referred to as a vacuum valve), and other switchgears (hereinafter referred to as a first switchgear) are applied.

[0003] The inside of the vacuum switchgear is maintained in a vacuum atmosphere, and in this vacuum atmosphere, a movable electrode and a fixed electrode are arranged so as to be openable and closable together with various conductors provided for energization. The inside of the first switchgear is maintained in an atmosphere of gas or liquid (in other words, an insulating atmosphere other than vacuum), and in this insulating atmosphere, a movable electrode and a fixed electrode are arranged so as to be openable and closable together with various conductors provided for energization.

[0004] Here, by opening (opening the circuit, separating) or closing (closing the circuit, contacting) the movable electrode with respect to the fixed electrode (that is, opening and closing (making and breaking) operation), interruption of accident current and opening and closing of energization (load) current are performed, and power is stably supplied from the switchgear.

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Patent Document 3

Patent Document 4

Summary of the Invention

[0006] Incidentally, the vacuum switch and the first switch are electrically connected in series with each other. Therefore, not only the current (load) but also large currents such as fault currents flow from the vacuum switch through the first switch. When a large current such as a fault current flows, a correspondingly large magnetic force is generated.

[0007] In vacuum switches, the fixed electrode and the movable electrode are pressed against each other with a preset pressure so that the closed (closed, contacted) state is maintained even when a large magnetic force is generated. For example, in the case of a fault current of several tens of kA, the pressurizing force can exceed 1000 N. For this reason, the structure (hereinafter referred to as the current-carrying structure) which includes the movable electrode and fixed electrode arranged to be switchable, along with the various conductors used for current transport as described above, has a large cross-sectional area (e.g., diameter, thickness) to ensure resistance to the applied pressure.

[0008] Furthermore, in vacuum switches, the energizing structure described above is prone to generating heat when energized. The energizing structure is housed inside a vacuum switch maintained in a vacuum atmosphere. Therefore, the heat generated from the energizing structure is difficult to dissipate from the vacuum switch to the outside due to the insulating effect of the vacuum. For this reason, the cross-sectional area (e.g., diameter, thickness) of the energizing structure is set to be large, thereby reducing electrical resistance (i.e., synonymous with electrical resistance) in order to suppress heat generation when energized.

[0009] In recent years, there has been a demand for miniaturization of the entire switchgear, including vacuum switches. However, as mentioned above, if the cross-sectional area of ​​the energized component is set large, there are certain limitations to the miniaturization of the vacuum switchgear, depending on its size. Therefore, it is undeniable that it may become impossible to meet the demand for miniaturization of the entire switchgear, including vacuum switches.

[0010] In this case, if a means to prevent large currents, such as fault currents, from flowing through the vacuum switch can be interposed between the vacuum switch and the first switch, it will be possible to meet the demand for miniaturization of the entire switch, including the vacuum switch.

[0011] For example, a second switch could be interposed between the vacuum switch and the first switch, and the second switch and the vacuum switch could be electrically connected in parallel. This would enable the aforementioned avoidance (shortcut, bypass) method, but such a technique is not currently known.

[0012] The object of the present invention is to provide a switch that can meet the demand for miniaturization by interposing a second switch between a vacuum switch and a first switch, and electrically connecting the second switch and the vacuum switch in parallel. [Means for solving the problem]

[0013] According to the embodiment, the device comprises a vacuum switch having a vacuum electrode that can be opened and closed in a vacuum atmosphere, a first switch having a first electrode that can be opened and closed in an insulating atmosphere other than a vacuum, and a second switch interposed between the vacuum switch and the first switch and having a second electrode that can be opened and closed in an insulating atmosphere other than a vacuum, wherein the first switch is electrically connected in series with the vacuum switch, and the second switch is electrically connected in parallel with the vacuum switch and electrically connected in series with the first switch. [Brief explanation of the drawing]

[0014] [Figure 1] A schematic wiring diagram showing the principle structure of a switch according to one embodiment. [Figure 2] A diagram showing the closed state of a switch according to one embodiment. [Figure 3] A diagram showing the intermediate opening state of a switch according to one embodiment. [Figure 4] A diagram showing the current interruption state of a switch according to one embodiment. [Figure 5]Arrangement configuration diagram showing the open-pole state of the switch according to one embodiment. [Figure 6] Arrangement configuration diagram showing the closed-pole state of the switch according to the first modification. [Figure 7] Arrangement configuration diagram showing the state during the opening of the switch according to the first modification. [Figure 8] Arrangement configuration diagram showing the current interruption state of the switch according to the first modification. [Figure 9] Arrangement configuration diagram showing the open-pole state of the switch according to the first modification. [Figure 10] Arrangement configuration diagram of the switch according to the second modification. [Figure 11] Arrangement configuration diagram of the switch according to the third modification.

Mode for Carrying Out the Invention

[0015] “One embodiment” FIG. 1 is a schematic diagram of the switch 1 according to the present embodiment. FIG. 1 shows the wiring structure of the switch 1 in which the vacuum switch 2, the first switch 3, and the second switch 4 are electrically connected to each other. In this wiring structure, the first switch 3 is connected in series with the vacuum switch 2. The second switch 4 is connected in parallel with the vacuum switch 2 and is also connected in series with the first switch 3.

[0016] In such a switch 1, the electrical resistance (also referred to as electrical resistance) of the second switch 4 and the first switch 3 is set lower than the electrical resistance of the vacuum switch 2. Note that the electrical resistance is a value indicating the degree of difficulty of current flow.

[0017] At this time, when the vacuum switch 2 and the first and second switches 3 and 4 are in the closed-pole (closed circuit, contact) state, not only the energization (load) current but also a large current such as an accident current flows from the second switch 4 via the first switch 3 while avoiding the vacuum switch 2. As a result, for example, countermeasures for the withstand voltage of the vacuum switch 2 are not required, and the vacuum switch 2 can be miniaturized accordingly. As a result, the entire switch 1 can be miniaturized.

[0018] Figure 2 is an internal structure diagram of switch 1 constructed based on the principle shown in Figure 1. Figure 2 shows switch 1 with a second switch 4 interposed between a vacuum switch 2 and a first switch 3. This switch 1 is provided with conductive movable electrode means for opening (opening, separating) or closing (closing, contacting) the first switch 3 and the second switch 4.

[0019] In Figure 2, as an example, the movable electrode means is applied individually to the first switch 3 and the second switch 4, one each, and is configured to have a first movable electrode 11 and a second movable electrode 8, which will be described later. A detailed explanation follows below.

[0020] In switch 1, the vacuum switch 2 and the second switch 4 are electrically connected in parallel to each other via various conductors 2a, 2b, 4a, and 4b used for energizing. The second switch 4 and the first switch 3 are electrically connected in series to each other via various conductors 3a and 4d used for energizing. The vacuum switch 2 and the first switch 3 are electrically connected in series to each other via various conductors 2a, 2b, 3a, 4a, 4b, and 4d used for energizing, as well as the second switch 4.

[0021] As shown in Figure 2, the vacuum switch 2 maintains a vacuum atmosphere inside 2p. The vacuum switch 2 comprises a vacuum operating rod 2R, a vacuum operating mechanism 2M, and a vacuum energizing structure 2S.

[0022] These components 2R, 2M, and 2S are housed inside the vacuum switch 2, 2p (i.e., in a vacuum atmosphere), which is maintained in a vacuum atmosphere. The vacuum atmosphere is assumed to be, for example, a low-pressure space that has a thermal insulating effect and contains no other materials.

[0023] The vacuum operating rod 2R is a straight, insulating rod-shaped member. The vacuum operating rod 2R is configured by connecting its base end 2Re to the vacuum operating mechanism 2M (described later) and its tip 2Rt to the movable electrode 6 (described later). The total length of the vacuum operating rod 2R (i.e., the distance between the base end 2Re and the tip 2Rt) is predetermined according to the operating environment and application, for example, and therefore is not specifically limited to a numerical value here.

[0024] The vacuum operating mechanism 2M is configured to allow a pressing or pulling force to be applied to the base end 2Re of the vacuum operating rod 2R. When a pressing or pulling force is applied to the base end 2Re of the vacuum operating rod 2R, this pressing or pulling motion is transmitted to the vacuum operating rod 2R. This allows the vacuum operating rod 2R to reciprocate in a direction parallel to its extending direction.

[0025] When the vacuum operating rod 2R is moved back and forth, the reciprocating motion is transmitted to the movable electrode 6, which will be described later, via the tip 2Rt of the vacuum operating rod 2R. This allows the movable electrode 6 to be opened (open circuit, separated) or closed (closed circuit, in contact) with the fixed electrode 7, which will be described later. As a result, the opening and closing (contact / separation) operation of the vacuum electrode 2E, which will be described later, is performed.

[0026] The vacuum current-carrying configuration structure 2S includes various conductors 2a and 2b used for current conduction, as well as a vacuum electrode 2E that is arranged to be switchable. Note that the vacuum current-carrying configuration structure 2S shown in Figure 2 is merely an example, and can be arranged and configured arbitrarily depending on the operating environment and application.

[0027] The vacuum electrode 2E comprises an insulating container 5 and a pair of electrodes (a movable electrode 6 and a fixed electrode 7). The inside of the insulating container 5 is maintained in a vacuum atmosphere. The pair of electrodes (movable electrode 6 and fixed electrode 7) are housed inside the insulating container 5. The movable electrode 6 is configured to be open and closed (contact and disconnected) from the fixed electrode 7.

[0028] The various conductors 2a and 2b used for energization are composed of two vacuum conductors 2a and 2b. Both vacuum conductors 2a and 2b are arranged parallel to each other so as not to touch, and each is conductive. One vacuum conductor 2a is electrically connected to the movable electrode 6 and extends from the movable electrode 6 toward the second switch 4. The other vacuum conductor 2b is electrically connected to the fixed electrode 7 and extends from the fixed electrode 7 toward the second switch 4.

[0029] As shown in Figure 2, the second switch 4 is maintained in an insulating atmosphere other than a vacuum inside its interior 4p. The second switch 4 comprises a second operating rod 4R, a second operating mechanism 4M, and a second energizing configuration structure 4S.

[0030] These components 4R, 4M, and 4S are housed inside the second switch 4, 4p (i.e., in an insulating atmosphere other than a vacuum), which is maintained in an insulating atmosphere other than a vacuum. An insulating atmosphere other than a vacuum could be, for example, an atmosphere of a gas or liquid that easily conducts large currents.

[0031] The second operating rod 4R is a straight, insulating rod-shaped member. The second operating rod 4R is configured by connecting its base end 4Re to the second operating mechanism 4M, which will be described later, and its tip 4Rt to the second movable electrode 8, which will be described later. The total length of the second operating rod 4R (i.e., the distance between the base end 4Re and the tip 4Rt) is predetermined according to the operating environment and application, for example, so no specific numerical limit is given here.

[0032] The second operating mechanism 4M is configured to allow a pressing or pulling force to be applied to the base end 4Re of the second operating rod 4R. When a pressing or pulling force is applied to the base end 4Re of the second operating rod 4R, this pressing or pulling motion is transmitted to the second operating rod 4R. This allows the second operating rod 4R to reciprocate in a direction parallel to its extending direction.

[0033] When the second operating rod 4R is moved back and forth, the reciprocating motion is transmitted to the second movable electrode 8, which will be described later, via the tip 4Rt of the second operating rod 4R. This allows the second movable electrode 8 to be opened (open circuit, separated) or closed (closed circuit, in contact) with respect to the contact fixed electrode 10, which will be described later. As a result, the opening and closing (contact / separation) operation of the second electrode 4E, which will be described later, is performed.

[0034] The second current-carrying configuration structure 4S is composed of various conductors 4a, 4b, 4c, and 4d used for current transport, along with a second electrode 4E that is arranged to be switchable. Note that the second current-carrying configuration structure 4S shown in Figure 2 is merely an example, and can be arranged and configured arbitrarily depending on the operating environment and application.

[0035] The second electrode 4E has one second movable electrode 8 and a pair of fixed electrodes (a sliding fixed electrode 9 and a contact fixed electrode 10). The second movable electrode 8 is a straight, conductive rod-shaped member. The second movable electrode 8 is connected to the tip 4Rt of the second operating rod 4R parallel to the extending direction (reciprocating direction) of the second operating rod 4R. The second movable electrode 8 is set to have a total length that allows it to simultaneously contact both fixed electrodes 9 and 10.

[0036] A pair of fixed electrodes (a sliding contact fixed electrode 9 and a contact fixed electrode 10) are arranged parallel to each other along the extending direction (reciprocating direction) of the second operating rod 4R. The distance between these two fixed electrodes 9 and 10 is set so that the second movable electrode 8 can simultaneously contact electrodes 9 and 10 with each other.

[0037] The sliding contact fixed electrode 9 is provided with a sliding contact passage H through which the second movable electrode 8 can slide while making electrical contact. The sliding contact passage H is configured to pass through the sliding contact fixed electrode 9 parallel to the extending direction (reciprocating direction) of the second operating rod 4R. The contact fixed electrode 10 is provided with a contact hole G through which the second movable electrode 8 can be inserted to make electrical contact, or removed to electrically separate them.

[0038] The various conductors 4a, 4b, 4c, and 4d used for energization are composed of four second conductors 4a, 4b, 4c, and 4d. Two second conductors 4a and 4b are arranged parallel to each other so as not to contact each other, and each is conductive. One second conductor 4a extends from and is electrically connected to the sliding contact fixed electrode 9 and is electrically connected to the one vacuum conductor 2a mentioned above. The other second conductor 4b extends from and is electrically connected to the contact fixed electrode 10 and is electrically connected to the other vacuum conductor 2b mentioned above.

[0039] The remaining two second conductors 4c and 4d are arranged parallel to each other so as not to touch, and each is conductive. One second conductor 4c is electrically connected to the contact fixed electrode 10 and extends from the contact fixed electrode 10 toward the outside of the second switch 4. The other second conductor 4d is electrically connected to the sliding contact fixed electrode 9 and extends from the sliding contact fixed electrode 9 toward the first switch 3.

[0040] As shown in Figure 2, the first switch 3 is maintained in an insulating atmosphere other than a vacuum inside its interior 3p. The first switch 3 comprises a first operating rod 3R, a first operating mechanism 3M, and a first energizing configuration structure 3S.

[0041] These components 3R, 3M, and 3S are housed inside the first switch 3, 3p (i.e., in an insulating atmosphere other than a vacuum), which is maintained in an insulating atmosphere other than a vacuum. An insulating atmosphere other than a vacuum could be, for example, an atmosphere of a gas or liquid that easily conducts large currents.

[0042] The first operating rod 3R is a straight, insulating rod-shaped member. The first operating rod 3R is configured by connecting its base end 3Re to the first operating mechanism 3M, which will be described later, and its tip 3Rt to the first movable electrode 11, which will be described later. The total length of the first operating rod 3R (i.e., the distance between the base end 3Re and the tip 3Rt) is predetermined according to the operating environment and application, for example, so no specific numerical limit is given here.

[0043] The first operating mechanism 3M is configured to apply a pressing or pulling force to the base end 3Re of the first operating rod 3R. When a pressing or pulling force is applied to the base end 3Re of the first operating rod 3R, this pressing or pulling motion is transmitted to the first operating rod 3R. This allows the first operating rod 3R to reciprocate in a direction parallel to its extending direction.

[0044] When the first operating rod 3R is moved back and forth, the reciprocating motion is transmitted to the first movable electrode 11, which will be described later, via the tip 3Rt of the first operating rod 3R. This allows the first movable electrode 11 to be opened (open circuit, separated) or closed (closed circuit, in contact) with respect to the contact fixed electrode 13, which will be described later. As a result, the opening and closing (contact / separation) operation of the first electrode 3E, which will be described later, is performed.

[0045] The first current-carrying configuration structure 3S includes various conductors 3a and 3b used for current transport, along with a first electrode 3E that is arranged to be switchable. Note that the first current-carrying configuration structure 3S shown in Figure 2 is merely an example, and can be arranged and configured arbitrarily depending on the operating environment and application.

[0046] The first electrode 3E has one first movable electrode 11 and a pair of fixed electrodes (a sliding fixed electrode 12 and a contact fixed electrode 13). The first movable electrode 11 is a straight, conductive rod-shaped member. The first movable electrode 11 is connected to the tip 3Rt of the first operating rod 3R parallel to the extending direction (reciprocating direction) of the first operating rod 3R. The first movable electrode 11 is set to have a total length that allows it to simultaneously contact both fixed electrodes 12 and 13.

[0047] A pair of fixed electrodes (a sliding contact fixed electrode 12 and a contact fixed electrode 13) are arranged parallel to each other along the extending direction (reciprocating direction) of the first operating rod 3R. The distance between these two fixed electrodes 12 and 13 is set so that the first movable electrode 11 can simultaneously contact electrodes 12 and 13 with each other.

[0048] The sliding contact fixed electrode 12 is provided with a sliding contact passage H through which the first movable electrode 11 can slide while making electrical contact. The sliding contact passage H is configured to pass through the sliding contact fixed electrode 12 parallel to the extending direction (reciprocating direction) of the first operating rod 3R. The abutment fixed electrode 13 is provided with a contact hole G through which the first movable electrode 11 can be inserted to make electrical contact, or withdrawn to make electrical separation.

[0049] The various conductors 3a and 3b used for energization are composed of two first conductors 3a and 3b. Both first conductors 3a and 3b are electrically conductive. One first conductor 3a is electrically connected to and extends from the contact fixed electrode 13 and is electrically connected to the other second conductor 4d described above. The other first conductor 3b is electrically connected to the sliding contact fixed electrode 12 and extends from the sliding contact fixed electrode 12 toward the outside of the first switch 3.

[0050] In such a switch 1, the electrical resistance of the first energizing configuration structure 3S (first switch 3) and the second energizing configuration structure 4S (second switch 4), including the movable electrode means (first movable electrode 11, second movable electrode 8) described above, is set lower than the electrical resistance of the vacuum energizing configuration structure 2S (vacuum switch 2).

[0051] For example, if the electrical resistance of the first energized structure 3S is R1, the electrical resistance of the second energized structure 4S is R2, and the electrical resistance of the vacuum energized structure 2S is R3, then the structure is set to satisfy one of the following relationships: R3>R2=R1, R3>R2>R1, or R3>R1>R2.

[0052] As a result, large currents, such as fault currents as well as the current (load) current, bypass the vacuum switch 2, which has a high electrical resistance R3, and instead flow through the first and second switches 3 and 4, which have low electrical resistances R1 and R2. In this state, the current interruption process described later takes place.

[0053] Figures 2 to 5 are process diagrams showing the transition from closed (closed circuit, contact) to open (open circuit, separation). Figure 2 shows the closed state, Figure 3 shows the intermediate open state, Figure 4 shows the current interruption state, and Figure 5 shows the open state.

[0054] In the closed state shown in Figure 2, the vacuum switch 2 closes the vacuum electrode 2E (i.e., the movable electrode 6 is in contact with the fixed electrode 7). The second switch 4 closes the second electrode 4E (i.e., the second movable electrode 8 is in contact with the contact fixed electrode 10). The first switch 3 closes the first electrode 3E (i.e., the first movable electrode 11 is in contact with the contact fixed electrode 13). At this time, most of the current flowing through the conductor 4c flows from the second electrode 4E through the first electrode 3E, thereby significantly suppressing the amount of current flowing to the vacuum electrode 2E.

[0055] In the intermediate opening state shown in Figure 3, the vacuum switch 2 maintains the closed state of the vacuum electrode 2E (i.e., the movable electrode 6 is in contact with the fixed electrode 7). The second switch 4 opens the second electrode 4E (i.e., the second movable electrode 8 is separated from the contact fixed electrode 10). The first switch 3 maintains the closed state of the first electrode 3E (i.e., the first movable electrode 11 is in contact with the contact fixed electrode 13). At this time, the current flowing through the conductor 4c is commutated from the second electrode 4E to the vacuum electrode 2E, and then flows through the first electrode 3E.

[0056] In the current interruption state shown in Figure 4, the vacuum switch 2 opens the vacuum electrode 2E (i.e., separates the movable electrode 6 from the fixed electrode 7). The second switch 4 maintains the open state of the second electrode 4E (i.e., separates the second movable electrode 8 from the contact fixed electrode 10). The first switch 3 maintains the closed state of the first electrode 3E (i.e., maintains the contact of the first movable electrode 11 with the contact fixed electrode 13). At this time, the current from the vacuum electrode 2E to the first electrode 3E is interrupted.

[0057] In the open state shown in Figure 5, the vacuum switch 2 maintains the open state of the vacuum electrode 2E (i.e., the movable electrode 6 is separated from the fixed electrode 7). The second switch 4 maintains the open state of the second electrode 4E (i.e., the second movable electrode 8 is separated from the contact fixed electrode 10). The first switch 3 opens the first electrode 3E (i.e., the first movable electrode 11 is separated from the contact fixed electrode 13). At this point, the current is interrupted. This completes the opening of the vacuum switch 2 and the first switch 3.

[0058] As described above, according to this embodiment, a second switch 4 is interposed between the vacuum switch 2 and the first switch 3 to avoid (i.e., bypass) the current to the vacuum switch 2, so that not only the energizing (load) current but also large currents such as fault currents do not flow to the vacuum switch 2. In this case, the magnetic force generated in the vacuum switch 2 is reduced, so the pressure required to bring electrodes 6 and 7 into contact with each other in the vacuum electrode 2E can be small. This makes it possible to reduce the cross-sectional area (e.g., diameter, thickness) of the vacuum energizing structure 2S. As a result, the entire switch 1, including the vacuum switch 2, can be miniaturized.

[0059] According to this embodiment, the opening of the vacuum switch 2 may be set to begin after the opening of the second switch 4 has begun but before the opening of the second switch 4 has ended, and while the insulation state of the second switch 4 is maintained at a constant level. In this case, when the vacuum switch 2 is opened and the current is interrupted, the second switch 4, which is connected in parallel with the vacuum switch 2, is in an open state to the extent that its insulation is ensured. This makes it possible to keep the probability of dielectric breakdown in the second switch 4 low.

[0060] According to this embodiment, the vacuum switch 2 may be set to open while the first switch 3 is closed. In this case, only the vacuum switch 2 is opened to interrupt the current. As a result, arc discharge during current interruption occurs only inside the vacuum electrode 2E of the vacuum switch 2 (i.e., the insulating container 5) and not at the first electrode 3E of the first switch 3 (i.e., between electrodes 11, 12, and 13). As a result, damage to the first electrode 3E of the first switch 3 and contamination of the surrounding area can be prevented.

[0061] According to this embodiment, after the second switchgear 4 is opened, the timing for starting to open the first switchgear 3 and the timing for starting to open the vacuum switchgear 2 may be set to be approximately the same. In this case, both timings may be set to be the same as each other, or they may be set to be different from each other.

[0062] Setting the timings of both devices to be different from each other includes both cases where one timing is set earlier than the other, or where one timing is set later than the other. In either case, the time required from the start to the end of opening the first switch 3, and the time required from the start to the end of opening the vacuum switch 2, include the elapsed time during which the opening operations of the first switch 3 and the vacuum switch 2 are performed simultaneously, that is, the elapsed time during which the opening operations of both devices overlap.

[0063] As a result, the current interruption process is performed by the opening timing of both the first switch 3 and the vacuum switch 2. At this time, the transient high voltage after the current interruption is applied to both the first switch 3 and the vacuum switch 2. In other words, the high voltage load is shared (distributed) between the first switch 3 and the vacuum switch 2. As a result, a switch 1 that can withstand even higher voltages can be realized.

[0064] "First Variation" In the embodiment described above, the movable electrode means is assumed to consist of a first movable electrode 11 and a second movable electrode 8, each individually applied to the first switch 3 and the second switch 4, respectively. However, instead, the first movable electrode 11 and the second movable electrode 8 may be integrated into a single unit.

[0065] Figures 6 to 9 are process diagrams showing the transition from closed to open in the switch 1 according to this modified example. Figure 6 shows the closed state, Figure 7 shows the intermediate open state, Figure 8 shows the current interrupted state, and Figure 9 shows the open state.

[0066] Figures 6 to 9 show a movable electrode means configured by integrating the first movable electrode 11 and the second movable electrode 8. The movable electrode means is configured as a single structure (i.e., a combined movable electrode 15, which will be described later) in which the first movable electrode 11 and the second movable electrode 8 are connected to each other in a straight line and integrated.

[0067] As shown in Figures 6 to 9, the switch 1 of this modified example is configured by electrically connecting a combined switch 14, which is formed by combining the first switch 3 and the second switch 4 of the above-described embodiment, with the vacuum switch 2 of the above-described embodiment. Since the vacuum switch 2 is the same as in the above-described embodiment, its description will be omitted, and the following description will be limited to the combined switch 14.

[0068] Figures 6 to 9 show an example of a combined structure of the first switch 3 and the second switch 4. That is, the combined switch 14 has its interior 14p maintained in an insulating atmosphere other than a vacuum. The combined switch 14 comprises an operating rod 14R, an operating mechanism 14M, and the second energizing configuration structure 4S (second electrode 4E) and the first energizing configuration structure 3S (first electrode 3E) of the embodiment described above.

[0069] These components 14R, 14M, 4S, and 3S are housed inside 14p of the combined switch 14 (i.e., in an insulating atmosphere other than a vacuum), which is maintained in an insulating atmosphere other than a vacuum. An insulating atmosphere other than a vacuum could be, for example, an atmosphere of a gas or liquid that easily conducts large currents.

[0070] The operating rod 14R is a straight, insulating rod-shaped member. The operating rod 14R is configured by connecting its base end 14Re to the operating mechanism 14M (described later) and its tip 14Rt to the combined movable electrode 15 (described later). The total length of the operating rod 14R (i.e., the distance between the base end 14Re and the tip 14Rt) is predetermined according to the operating environment and application, for example, so no specific numerical limit is given here.

[0071] The operating mechanism 14M is configured to apply a pressing or pulling force to the base end 14Re of the operating rod 14R. When a pressing or pulling force is applied to the base end 14Re of the operating rod 14R, the pressing or pulling motion is transmitted to the operating rod 14R. This allows the operating rod 14R to reciprocate in a direction parallel to its extending direction.

[0072] When the operating rod 14R is moved back and forth, the reciprocating motion is transmitted to the combined movable electrode 15, which will be described later, via the tip 14Rt of the operating rod 14R. This allows the combined movable electrode 15 to be opened (open circuit, separated) or closed (close circuit, in contact) with respect to the contact fixed electrode 18 and the common sliding contact fixed electrode 17, which will be described later. As a result, the opening and closing (contact and separation) operations of the second electrode 4E and the first electrode 3E, which will be described later, are performed.

[0073] Inside the combined switch 14p, three fixed electrodes 16, 17, and 18 are provided at equal intervals and parallel to each other along the extending direction (reciprocating direction) of the operating rod 14R. These three fixed electrodes 16, 17, and 18 are configured with a common sliding contact fixed electrode 17 in the center, flanked by one sliding contact fixed electrode 16 and one abutment fixed electrode 18 on either side.

[0074] The combined movable electrode 15 is connected to the tip 14Rt of the operating rod 14R, parallel to the operating rod 14R's extending direction (reciprocating direction). The combined movable electrode 15 is set to have a total length that allows it to simultaneously contact the three fixed electrodes (sliding contact fixed electrode 16, common sliding contact fixed electrode 17, and contact fixed electrode 18).

[0075] The sliding contact fixed electrode 16 and the common sliding contact fixed electrode 17 are provided with a sliding contact passage H through which the combined movable electrode 15 can slide while in electrical contact. The sliding contact passage H is configured to pass through the respective fixed electrodes 16 and 17 parallel to the extending direction (reciprocating direction) of the operating rod 14R. The contact fixed electrode 18 is provided with a contact hole G through which the combined movable electrode 15 can be inserted and electrically contacted, or removed and electrically separated.

[0076] In this case, the first energizing configuration structure 3S (i.e., the first electrode 3E) of the above embodiment is composed of a fixed electrode 16 for sliding contact, a fixed electrode 17 for common sliding contact, and a combined movable electrode 15 between these two fixed electrodes 16 and 17.

[0077] Furthermore, the second energizing configuration structure 4S (i.e., the second electrode 4E) of the above-described embodiment is composed of a common sliding contact fixed electrode 17, a contact fixed electrode 18, and a combined movable electrode 15 between these two fixed electrodes 17 and 18.

[0078] Furthermore, the first and second energizing structures 3S and 4S are provided with four common conductors 14a, 14b, 14c, and 14d, which are used as various conductors for energizing that are common to both of these energizing structures 3S and 4S.

[0079] The two common conductors 14a and 14b are arranged parallel to each other so as not to touch, and each is conductive. One common conductor 14a extends from and is electrically connected to the common sliding contact fixed electrode 17, and is electrically connected to one of the vacuum conductors 2a of the vacuum switch 2. The other common conductor 14b extends from and is electrically connected to the contact fixed electrode 18, and is electrically connected to the other vacuum conductor 2b of the vacuum switch 2.

[0080] The remaining two common conductors 14c and 14d are arranged parallel to each other so as not to touch, and each is conductive. One common conductor 14c is electrically connected to a contact fixed electrode 18 and extends from the contact fixed electrode 18 toward the outside of the combined switch 14. The other common conductor 14d is electrically connected to a sliding contact fixed electrode 16 and extends from the sliding contact fixed electrode 16 toward the outside of the combined switch 14.

[0081] The other configurations are the same as those in the embodiment described above, so their explanation will be omitted. As a result, as in the embodiment described above, large currents such as fault currents, as well as the energizing (load) current, will flow through the combined switch 14 with low electrical resistances R1 and R2, while avoiding (shortcutting, bypassing) the vacuum switch 2 with high electrical resistance R3. In this state, the current interruption process described later will be performed.

[0082] Figures 6 to 9 are process diagrams showing the transition from closed (closed circuit, contact) to open (open circuit, separation). Figure 6 shows the closed state, Figure 7 shows the intermediate open state, Figure 8 shows the current interruption state, and Figure 9 shows the open state.

[0083] In the closed state shown in Figure 6, the vacuum switch 2 closes the vacuum electrode 2E (i.e., the movable electrode 6 is in contact with the fixed electrode 7). In the combined switch 14, the second electrode 4E is closed (i.e., the combined movable electrode 15 is in contact with the contact fixed electrode 18), and at the same time, the first electrode 3E is closed (i.e., the combined movable electrode 15 is in contact with the common sliding fixed electrode 17). At this time, most of the current flowing through the common conductor 14c flows from the second electrode 4E through the first electrode 3E, thereby significantly suppressing the amount of current flowing to the vacuum electrode 2E.

[0084] In the intermediate opening state shown in Figure 7, the vacuum switch 2 maintains the closed state of the vacuum electrode 2E (i.e., the movable electrode 6 is in contact with the fixed electrode 7). In the combined switch 14, the second electrode 4E is opened (i.e., the combined movable electrode 15 is separated from the contact fixed electrode 18), and at the same time, the first electrode 3E is closed (i.e., the combined movable electrode 15 is in contact with the common sliding fixed electrode 17). At this time, the current flowing through the common conductor 4c is commutated from the second electrode 4E to the vacuum electrode 2E, and then flows through the first electrode 3E.

[0085] In the current interruption state shown in Figure 8, the vacuum switch 2 opens the vacuum electrode 2E (i.e., separates the movable electrode 6 from the fixed electrode 7). In the combined switch 14, the second electrode 4E remains open (i.e., separates the combined movable electrode 15 from the contact fixed electrode 18), while the first electrode 3E remains closed (i.e., maintains contact between the combined movable electrode 15 and the common sliding fixed electrode 17). At this time, the current from the vacuum electrode 2E to the first electrode 3E is interrupted.

[0086] In the open state shown in Figure 9, the vacuum switch 2 maintains the open state of the vacuum electrode 2E (i.e., the movable electrode 6 is separated from the fixed electrode 7). In the combined switch 14, the open state of the second electrode 4E (i.e., the separation of the second movable electrode 8 from the contact fixed electrode 10) is maintained, and at the same time, the first electrode 3E is opened (i.e., the combined movable electrode 15 is separated from the common sliding contact fixed electrode 17). At this point, the current is interrupted. This completes the opening of both the vacuum switch 2 and the combined switch 14.

[0087] As described above, according to this modified version, by integrating the first switch 3 and the second switch 4 of the above-described embodiment into a combined switch 14, the entire switch 1, including the vacuum switch 2, can be further miniaturized. Other effects are the same as those of the above-described embodiment, and therefore their explanation is omitted.

[0088] "Second variation" Figure 10 is an internal structure diagram of the switch 1 according to this modified example. Figure 10 shows a layout in which the vacuum switch 2 and the second switch 4 of the above-described embodiment are provided on the first operating mechanism 3M side of the first switch 3.

[0089] In Figure 10, as an example, the first switch 3 is positioned at a predetermined distance from the first operating mechanism 3M, when viewed in the extending direction (reciprocating direction) of the first operating rod 3R. Using the position of the first switch 3 as a reference, the vacuum switch 2 and the second switch 4 are positioned closer to the first operating mechanism 3M than the first switch 3.

[0090] To achieve this arrangement, the various conductors 19a, 19b, 19c, and 19d used for conducting electricity are configured with a layout different from that of the embodiment described above. Each conductor 19a, 19b, 19c, and 19d is arranged parallel to each other so as not to touch, and each is conductive.

[0091] One conductor 19a is electrically connected to the contact fixed electrode 13 and extends from the contact fixed electrode 13 toward the outside of the first switch 3. One conductor 19b is interposed between the sliding fixed electrode 12 and the contact fixed electrode 10, electrically connecting both electrodes 12 and 10. One conductor 19c is interposed between the contact fixed electrode 10 and the fixed electrode 7, electrically connecting both electrodes 10 and 7. One conductor 19d is electrically connected to the sliding fixed electrode 9 and extends from the sliding fixed electrode 9 through the movable electrode 6 toward the outside of the vacuum switch 2.

[0092] As described above, according to this modified example, the total length of all operating rods 2R and 4R for opening and closing the vacuum switch 2 and the second switch 4 is set to be shorter than the total length of the first operating rod 3R. As a result, the size of the vacuum switch 2 and the second switch 4 can be made more compact by the amount by which the total length of all operating rods 2R and 4R has been shortened. As a result, the entire switch 1 can be made even smaller. Note that the other configurations and effects are the same as in the embodiment described above, so their explanation will be omitted.

[0093] "Third Variation" Figure 11 is an internal structure diagram of the switch 1 according to this modified example. Figure 11 shows a layout in which the vacuum energizing configuration structure 2S, the first energizing configuration structure 3S, and the second energizing configuration structure 4S of the vacuum switch 2, first switch 3, and second switch 4 of the above-described embodiment are housed inside a single container 20.

[0094] In Figure 11, as an example, in the switch 1 of the second modified example described above, all electrodes 2E, 4E, and 3E, along with the various conductors 19a, 19b, 19c, and 19d used for energizing, are housed inside a single container 20.

[0095] As shown in Figure 11, the container 20 is maintained in an insulating atmosphere of gas or liquid inside 20p. As a result, all electrodes 2E, 4E, and 3E, along with the various conductors 19a, 19b, 19c, and 19d used for energization, are housed in an airtight or liquidtight manner inside 20p of the container 20.

[0096] As insulating gases, naturally occurring gases such as dry air, nitrogen, oxygen, and carbon dioxide, as well as mixtures thereof, and artificial gases such as sulfur hexafluoride gas (SF6) can be used. The gas pressure inside container 20 (20p) may be set to a pressure higher than atmospheric pressure if necessary. Examples of insulating liquids that can be used include vegetable-based insulating oils, mineral oils, and synthetic oils.

[0097] As described above, according to this modified example, naturally occurring or artificial gases, for example, have high arc extinguishing capabilities when current is interrupted, thus enabling reliable current interruption. As a result, insulation reliability after insulation interruption can be ensured.

[0098] According to this modified example, for example, by placing all electrodes 2E, 4E, and 3E together with the various conductors 19a, 19b, 19c, and 19d used for current conduction in the insulating liquid described above, the temperature rise during current conduction can be suppressed. The other configurations and effects are the same as those of the embodiment described above, so their explanation will be omitted.

[0099] Although one embodiment of the present invention and several variations have been described above, these embodiments and variations are presented as examples and are not intended to limit the scope of the invention. These embodiments and variations can be implemented in a variety of other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and variations are included in the scope and spirit of the invention, as well as in the claims of the invention and its equivalents. [Explanation of Symbols]

[0100] 1…Opening / closing device, 2…Vacuum opening / closing device, 2p…Interior, 2R…Vacuum operating rod, 2M…Vacuum operating mechanism, 2S…Vacuum energizing structure, 2Re…Base end, 2Rt…Tip end, 2a, 2b…Vacuum conductors, 2E…Vacuum electrode, 3…First opening / closing device, 3p…Interior, 4…Second opening / closing device, 4R…Second operating rod, 4M…Second operating mechanism, 4S…Second energizing structure, 4Re…Base end, 4Rt…Tip end, 4a, 4b, 4c, 4d…Second conductors, 4E…Second electrode, 4p…Interior, 5…Insulation container, 6…Movable electrode, 7…Fixed electrode, 8…Second movable electrode, 9…Fixed fixed electrode, 10… …When connected to a fixed electrode, 3R…first operating rod, 3M…first operating mechanism, 3S…first energized structure, 3Re…base end, 3Rt…terminal end, 3a, 3b…first conductor, 3E…first electrode, 11…first movable electrode, 12…fixed electrode for folding, 13…fixed electrode for connection, 14…combined opening and closing device, 14a, 14b, 14c, 14d…common conductor, 14R…operating rod, 14M…operating mechanism, 15…combined movable electrode, 16…fixed electrode for folding, 17…common fixed electrode for folding, 18…fixed electrode for connection, 19a, 19b, 19c, 19d…conductors, 20…container, 20p…inside.

Claims

1. A vacuum switch having a vacuum electrode that can be opened and closed in a vacuum atmosphere, A first switch having a first electrode that can be opened and closed in an insulating atmosphere other than a vacuum, The system comprises a second switch interposed between the vacuum switch and the first switch, having a second electrode that can be opened and closed in an insulating atmosphere other than a vacuum, The first switch is electrically connected in series with the vacuum switch, The second switch is a switch that is electrically connected in parallel with the vacuum switch and electrically connected in series with the first switch.

2. The vacuum switch houses a vacuum current-carrying structure that includes the vacuum electrode along with various conductors used for energizing. The first switch houses a first current-carrying configuration structure which includes the first electrode along with various conductors used for energizing, The second switch houses a second current-carrying configuration structure which includes the second electrode along with various conductors used for energizing. The first energizing configuration is electrically connected in series with the vacuum energizing configuration, The switch according to claim 1, wherein the second energizing configuration is electrically connected in parallel with the vacuum energizing configuration and electrically connected in series with the first energizing configuration.

3. The aforementioned switch is The first switch and the second switch are provided with conductive movable electrode means for opening or closing them, The switch according to claim 2, wherein the electrical resistance of the first energizing configuration structure and the second energizing configuration structure, including the movable electrode means, is set lower than the electrical resistance of the vacuum energizing configuration structure.

4. If the electrical resistance of the first current-carrying structure is R1, the electrical resistance of the second current-carrying structure is R2, and the electrical resistance of the vacuum current-carrying structure is R3, The switch according to claim 3, which is set to satisfy any of the following relationships: R3 > R2 = R1, R3 > R2 > R1, or R3 > R1 > R2.

5. The movable electrode means is A conductive first movable electrode for opening or closing the first switch, The switch according to claim 3, further comprising a conductive second movable electrode for opening or closing the second switch.

6. The movable electrode means is The switch according to claim 5, wherein the first movable electrode and the second movable electrode are integrated into one unit.

7. The movable electrode means is The switch according to claim 6, wherein the first movable electrode and the second movable electrode are connected to each other in a straight line and integrated as a single structure.

8. The aforementioned switch is An insulating first operating rod that opens and closes the first switch and has a predetermined total length, The device comprises an operating mechanism for moving the first operating rod, Viewed in the direction of movement of the first operating rod, the first switch is positioned at a predetermined distance from the operating mechanism, while the vacuum switch and the second switch are positioned closer to the operating mechanism than the first switch. As a result, the total length of all operating rods for opening and closing the vacuum switch and the second switch is set to be shorter than the total length of the first operating rod, as described in claim 1.

9. After the opening of the second switch is initiated, and before the opening of the second switch is terminated, and while the insulation state of the second switch is maintained at a constant level, The switch according to claim 1, which is set to initiate the opening of the vacuum switch.

10. The switch according to claim 9, which is configured such that the opening of the vacuum switch is initiated while the first switch is closed.

11. After the second switch is opened, the timing for starting to open the first switch and the timing for starting to open the vacuum switch are: The switch according to claim 9, wherein the timings of both sides are set to be the same, or to be different from each other.

12. For the timings of both to be set differently from each other, This includes both cases where one timing is set earlier than the other timing, or where one timing is set later than the other timing. The switch according to claim 11, wherein the time required from the start to the end of opening the first switch and the time required from the start to the end of opening the vacuum switch include the elapsed time during which the opening operation of the first switch and the opening operation of the vacuum switch are performed simultaneously.

13. The switch is, It comprises a container whose interior is maintained in a gaseous insulating atmosphere, The switch according to claim 2, wherein the container hermetically houses the vacuum energizing configuration structure of the vacuum switch, the first energizing configuration structure of the first switch, and the second energizing configuration structure of the second switch.

14. The switch is, It comprises a container whose interior is maintained in a liquid insulating atmosphere, The switch according to claim 2, wherein the container contains in a liquid-tight manner the vacuum energizing configuration structure of the vacuum switch, the first energizing configuration structure of the first switch, and the second energizing configuration structure of the second switch.

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