Switch

Abstract

The present invention provides a switch comprising: a fixed contact (24b); a movable contact (25b) that comes in contact with and separates from the fixed contact (24b) in association with a rotational travel of a rod-shaped movable contactor (22b); and a metal grid (26b) disposed so as to oppose the fixed contact (24b) in a second direction orthogonal to a first direction and along the longitudinal direction of the movable contactor (22b), the first direction being the movable direction of the movable contact (25b). The grid (26b) returns a gas flow flowing along the second direction from the movable contact (25b) and the fixed contact (24b) toward the grid (26b) to a periphery of the movable contact (25b) and the fixed contact (24b), the gas flow being generated between the movable contact (25b) and the fixed contact (24b) at the time of an opening operation in which the fixed contact (24b) separates from the movable contact (25b).

Description

Technical Field

[0001] The present disclosure relates to a switch disposed between a power source and a load.

Background Art

[0002] Conventionally, a contact switch having a grid, which is a metal member composed of three sides and surrounds a movable contact and a fixed contact from three directions, is known. In a contact switch having a grid, an electromagnetic force acts on an arc generated between the movable contact and the fixed contact during an opening operation in which the movable contact separates from the fixed contact. The arc is attracted from between the movable contact and the fixed contact to the grid and is interrupted by being extended. Thus, a contact switch having a grid can quickly interrupt the arc generated during the opening operation.

[0003] Patent Document 1 discloses a contact switch in which left and right reflux side plates standing upright left and right are disposed inside a grid block. The contact switch disclosed in Patent Document 1 guides an arc into the grid block through the inside of the left and right reflux side plates, and refluxes a gas flow of hot gas generated between the movable contact and the fixed contact around the movable contact and the fixed contact by the left and right reflux side plates. The hot gas generated during the opening operation has a lower temperature than the arc and has an arc cooling effect. Therefore, by returning the hot gas around the movable contact and the fixed contact, the arc extinction can be promoted.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the contact switch disclosed in Patent Document 1, the grid is formed by multiple plate-shaped members, which causes hot gas to leak through the gaps between the plate-shaped members, reducing the effect of promoting arc extinguishing. For this reason, there was room to further improve the performance of the contact switch disclosed in Patent Document 1 in interrupting the arc generated during opening operation.

[0006] This disclosure has been made in view of the above, and aims to provide a switch with high performance in interrupting arcs generated during opening operation. [Means for solving the problem]

[0007] To solve the aforementioned problems and achieve the objective, the switch according to this disclosure comprises a fixed contact, a movable contact installed on a rotatable rod-shaped movable contact that contacts and separates from the fixed contact as the movable contact rotates, and a metal grid positioned opposite the fixed contact in a second direction perpendicular to a first direction which is the direction of movement of the movable contact, and along the longitudinal direction of the movable contact. The grid returns the gas flow that flows from the movable contact and the fixed contact toward the grid in the second direction, which occurs between the movable contact and the fixed contact during an opening operation in which the fixed contact separates from the movable contact, to the vicinity of the movable contact and the fixed contact. [Effects of the Invention]

[0008] According to this disclosure, it is possible to obtain a switch with high performance in interrupting the arc generated during opening operation. [Brief explanation of the drawing]

[0009] [Figure 1] Top view of the switch according to Embodiment 1 [Figure 2] A schematic diagram showing a cross-section of the switch according to Embodiment 1. [Figure 3] Top view of the internal structure of the second phase arc extinguishing chamber of the switch according to Embodiment 1 [Figure 4] This figure schematically shows a cross-sectional view of the internal structure of the second phase arc extinguishing chamber of the switch according to Embodiment 1. [Figure 5] This figure shows the state in which an arc occurs between the movable contact and the fixed contact of the switch according to Embodiment 1. [Figure 6] Perspective view of the internal structure of the second phase arc extinguishing chamber of the switch according to Embodiment 2 [Figure 7] Top view of the internal structure of the second phase arc extinguishing chamber of the switch according to Embodiment 2 [Figure 8] Top view of the internal structure of the second phase arc extinguishing chamber of the switch according to the first modified example of Embodiment 2. [Figure 9] Cross-sectional view of the internal structure of the second phase arc extinguishing chamber of a switch according to the first modified example of Embodiment 2. [Figure 10] Top view of the internal structure of the second phase arc extinguishing chamber of the switch according to a second modified example of Embodiment 2. [Figure 11] Cross-sectional view of the internal structure of the second phase arc extinguishing chamber of a switch according to a second modified example of Embodiment 2. [Figure 12] Top view of the internal structure of the second phase arc extinguishing chamber of the switch according to Embodiment 3 [Figure 13] Top view of the internal structure of the second phase arc extinguishing chamber of the switch according to Embodiment 4 [Figure 14] Perspective view of the internal structure of the second phase arc extinguishing chamber of a switch according to a modified example of Embodiment 4. [Figure 15] Top view of the internal structure of the second phase arc extinguishing chamber of the switch according to Embodiment 5 [Figure 16] Perspective view of the grid of the switch according to Embodiment 6 [Figure 17] Perspective view of the internal structure of the second phase arc extinguishing chamber of the switch according to Embodiment 7 [Modes for carrying out the invention]

[0010] The switch according to the embodiment will be described in detail below with reference to the drawings.

[0011] Embodiment 1. FIG. 1 is a top view of the switch according to Embodiment 1. FIG. 2 is a diagram schematically showing a cross section of the switch according to Embodiment 1. FIG. 2 schematically shows a cross section of the switch 1 along line II-II in FIG. 1. As shown in FIGS. 1 and 2, the Y direction, the Z direction, and the X direction are defined as directions orthogonal to each other. Specifically, the first direction, which is the direction in which the movable contact 25b and the fixed contact 24b come into contact with and separate from each other and is the movable direction of the movable contact 25b, is defined as the Z direction. The second direction, which is a direction orthogonal to the Z direction and along the longitudinal direction of the movable contact 22b described later, is defined as the Y direction. The third direction, which is a direction orthogonal to the Z direction and the Y direction and along the short-side direction of the movable contact 22b described later, is defined as the X direction. Also, the Z direction is a general term for the +Z direction and the -Z direction indicating opposite directions, the Y direction is a general term for the +Y direction and the -Y direction indicating opposite directions, and the X direction is a general term for the +X direction and the -X direction indicating opposite directions. In the following description, an example is given in which the +Z direction corresponds to the upward direction, the -Z direction corresponds to the downward direction, the +Y direction corresponds to the forward direction, the -Y direction corresponds to the rearward direction, the +X direction corresponds to the leftward direction, and the -X direction corresponds to the rightward direction. However, this example does not limit the posture of installing the switch 1.

[0012] The switch 1 is, for example, a contact switch configured for a three-phase power supply and has three arc extinguishing chambers. Since the switch 1 has the same structure for each phase, only the structure of one phase will be described below, and other phases with overlapping descriptions are omitted but have the same structure.

[0013] As shown in FIGS. 1 and 2, the switch 1 includes a contact portion 1A having first-phase arc extinguishing chamber 21a, second-phase arc extinguishing chamber 21b, and third-phase arc extinguishing chamber 21c adjacent to each other, an opening / closing mechanism portion 1B for driving the contact portion 1A, and a relay portion 1C for operating the opening / closing mechanism portion 1B when overcurrent is detected.

[0014] Fixed contacts 23a, 23b, and 23c are connected to the wiring of one phase of a three-phase power supply (not shown) via power supply side terminals 231a, 231b, and 231c, respectively, and fixed terminals 23d, 23e, and 23f are connected to the wiring of a load (not shown) via load side terminals 231d, 231e, and 231f, respectively. The first phase arc extinguishing chamber 21a, the second phase arc extinguishing chamber 21b, and the third phase arc extinguishing chamber 21c have the same structure. Therefore, the following will mainly describe the structure of the second phase arc extinguishing chamber 21b, and will omit redundant explanations of the structures of the first phase arc extinguishing chamber 21a and the third phase arc extinguishing chamber 21c.

[0015] Figure 3 is a top view of the internal structure of the second phase arc extinguishing chamber of the switch according to Embodiment 1. Figure 4 is a schematic diagram showing a cross-section of the internal structure of the second phase arc extinguishing chamber of the switch according to Embodiment 1. Figure 4 shows the cross-sectional structure of the internal structure of the second phase arc extinguishing chamber 21b along the line IV-IV in Figure 3. Figures 3 and 4 show the positional relationship between the movable contact 22b with a movable contact 25b, the fixed contact 23b with a fixed contact 24b, and the grid 26b and two insulating members 271b and 272b located near them, on the power supply side of one phase of the three-phase power supply. However, the structure is similar on the power supply side of the other two phases, so a redundant explanation is omitted here.

[0016] The second phase arc extinguishing chamber 21b includes a fixed contactor 23b provided with a fixed contact 24b, a movable contactor 22b provided with a movable contact 25b, a grid 26b provided near the fixed contact 24b and the movable contact 25b, and two insulating members 271b and 272b provided near the grid 26b.

[0017] The grid 26b is formed of a magnetic material such as iron. When a fault current is detected, the movable contact 25b separates from the fixed contact 24b, causing hot gas to be generated between the movable contact 25b and the fixed contact 24b, moving in the +Y direction from either the movable contact 25b or the fixed contact 24b, along with the arc. The grid 26b forms a flow path that directs the hot gas moving forward from either the movable contact 25b or the fixed contact 24b towards the ±X and -Y directions of the movable contact 25b or the fixed contact 24b. In other words, the grid 26b has the function of reversing the direction of the hot gas flow.

[0018] Furthermore, as shown in Figures 3 and 4, the grid 26b is positioned on the longitudinal extension of the movable contact 22b and has multiple surfaces surrounding the fixed contact 24b. Specifically, as shown in Figure 3, the grid 26b has two opposing side portions 261b and 262b that cover the fixed contact 24b, and a connecting portion 263b that connects them, and has a U-shape when viewed from above. The side portions 261b and 262b sandwich the fixed contact 24b in the X direction, which is perpendicular to the Z direction, which is the direction of movement of the movable contact 22b. The connecting portion 263b faces the fixed contact 24b in the Y direction, which is perpendicular to the Z direction, which is the direction of movement. In addition, the dimension of the connecting portion 263b in the Z direction, which is the direction of movement of the movable contact 22b, is greater than or equal to the dimension in the Y direction. As shown in Figures 3 and 4, when the movable contact 25b is located near the fixed contact 24b, the movable contact 25b is covered together with the fixed contact 24b by the two side portions 261b, 262b and the connecting portion 263b.

[0019] The two insulating members 271b and 272b are positioned inside the grid 26b, between the fixed contact 24b and the grid 26b, such that at least a portion of the connecting portion 263b of the grid 26b is exposed when viewed from the fixed contact 24b. The inside of the grid 26b is the region enclosed on three sides by the connecting portion 263b and the two side portions 261b and 262b. Here, it is not necessary to place both insulating members 271b and 272b; it is sufficient if at least one is placed.

[0020] When a fault current is detected, the hot gas flowing from the movable contact 25b and the fixed contact 24b in the +Y direction changes direction in the ±X direction when it hits the connecting portion 263b, and then changes direction in the -Y direction along the side portions 261b, 262b and the insulating members 271b, 272b. As a result, the hot gas generated between the movable contact 25b and the fixed contact 24b is returned to the vicinity of the movable contact 25b and the fixed contact 24b by the grid 26b.

[0021] The movable contact 22b is driven by the switching mechanism 1B and rotates around the drive shaft 221b shown in Figure 4. Specifically, when energized, the switching mechanism 1B rotates the movable contact 22b around the drive shaft 221b until the movable contact 25b and the fixed contact 24b make contact. Furthermore, when the relay unit 1C detects a fault current, it activates the switching mechanism 1B and rotates the movable contact 22b around the drive shaft 221b in a direction that moves the movable contact 25b away from the fixed contact 24b.

[0022] When an overcurrent is detected, the relay unit 1C activates the switching mechanism unit 1B, causing the movable contact 25b to separate from the fixed contact 24b, which generates an arc between the movable contact 25b and the fixed contact 24b. The process of interrupting the arc generated between the movable contact 25b and the fixed contact 24b will now be described. Figure 5 shows the state in which an arc has been generated between the movable contact and the fixed contact of the switch according to Embodiment 1. Immediately after the movable contact 25b separates from the fixed contact 24b, an arc connecting the movable contact 25b and the fixed contact 24b is generated at position A1. In addition to the grid 26b acting an electromagnetic force on the arc in the +Y direction, the gas flow of hot gas generated between the movable contact 25b and the fixed contact 24b in the +Y direction drives the arc, causing the arc, which is pulled to the connecting portion 263b of the grid 26b, to move to position A2 through the insulating members 271b and 272b. When the arc attracted to the grid 26b comes into contact with the connecting portion 263b, current flows within the grid 26b, causing the arc to move to positions A3 and A4 and be interrupted. The interruption of the arc completes the disconnection of the arc generated between the movable contact 25b and the fixed contact 24b.

[0023] The switch 1 according to Embodiment 1 drives the arc generated between the movable contact 25b and the fixed contact 24b toward the grid 26b in the +Y direction by electromagnetic force, and also drives the arc generated between the movable contact 25b and the fixed contact 24b in the +Y direction by the gas flow of hot gas generated between the movable contact 25b and the fixed contact 24b. Furthermore, the switch 1 according to Embodiment 1 can increase the driving force of the arc and improve the cooling effect of the arc by directing the gas flow of hot gas, whose direction of travel has been changed at the connecting portion 263b, toward the -Y direction along the side portions 261b and 262b of the grid 26b. As a result, the switch 1 according to Embodiment 1 can quickly extend and interrupt the arc toward the grid 26b, thereby completing arc interruption at a faster speed.

[0024] Furthermore, as shown in Figures 3 and 4, the switch 1 according to Embodiment 1 has a grid 26b in which the dimension in the Z direction, which is the operating direction of the movable contact 22b, is greater than or equal to the dimension in the Y direction, which is the arrangement direction of the fixed contact 24b and the connecting portion 263b, and which has 3 or more faces. Therefore, the volume of the magnetic material can be increased and the electromagnetic force acting on the arc can be strengthened. For this reason, the switch 1 according to Embodiment 1 can quickly extend and break the arc, thereby completing arc interruption at high speed. In addition, since the switch 1 according to Embodiment 1 has insulating members 271b and 272b installed inside the grid 26b, the arc can be moved to the connecting portion 263b, which is exposed at least in part, without the arc coming into contact with the side portions 261b and 262b of the grid 26b, and arc interruption can be reliably completed.

[0025] Embodiment 2. Figure 6 is a perspective view of the internal structure of the second phase arc extinguishing chamber of the switch according to Embodiment 2. Figure 7 is a top view of the internal structure of the second phase arc extinguishing chamber of the switch according to Embodiment 2. The switch 1 according to Embodiment 2 differs from the switch 1 according to Embodiment 1 in that a gap 91 is formed between each of the insulating members 271b and 272b and the grid 26b. In the switch 1 according to Embodiment 2, a return channel X1 is formed between the insulating members 271b and 272b, a return channel X2 is formed between the side portion 261b and the insulating member 271b by a gap 91, and a return channel X3 is formed between the side portion 262b and the insulating member 272b by a gap 91.

[0026] When the contacts are opened, some of the hot gas generated with the arc between the movable contact 25b and the fixed contact 24b flows from the movable contact 25b and the fixed contact 24b toward the grid 26b in the +Y direction. The hot gas that collides with the connecting portion 263b branches into ±X directions perpendicular to the Z direction, which is the direction of movement of the movable contact 22b. The hot gas travels along the inner surface of the grid 26b and flows through the return channels X2 and X3 in the -Y direction, opposite to the hot gas in the return channel X1.

[0027] Because a gap 91 is formed between each of the insulating members 271b, 272b and the grid 26b, the distance between the insulating members 271b, 272b is narrower compared to the switch 1 according to Embodiment 1. Therefore, the gas flow of hot gas flowing in the +Y direction through the return channel X1 formed between the insulating members 271b, 272b is stronger compared to the switch 1 according to Embodiment 1. In addition, because return channels X2, X3 are formed between the insulating members 271b, 272b and the side portions 261b, 262b, the gas flow of hot gas flowing in the -Y direction along the side portions 261b, 262b and the insulating members 271b, 272b is stronger compared to the switch 1 according to Embodiment 1. Furthermore, because the return channel X1 and the return channels X2, X3 are separated by the insulating members 271b, 272b, the hot gas flowing in the +Y direction and the hot gas flowing in the -Y direction do not interfere with each other and weaken each other.

[0028] Figure 8 is a top view of the internal structure of the second phase arc extinguishing chamber of the switch according to the first modified example of Embodiment 2. Figure 9 is a cross-sectional view of the internal structure of the second phase arc extinguishing chamber of the switch according to the first modified example of Embodiment 2. Figure 9 shows a cross-section of the internal structure of the second phase arc extinguishing chamber 21b along the line IX-IX in Figure 8. In the switch 1 according to the first modified example of Embodiment 2, the insulating members 271b and 272b have lower parts 31b and 32b that are opposite to the side parts 261b and 262b and are lower than the side parts 261b and 262b. The distance between the lower parts 31b and 32b and the fixed contact 24b in the first direction is shorter than the distance between the ends of the side parts 261b and 262b in the first direction and the fixed contact 24b. In the switch 1 according to the first modified example of Embodiment 2, the space above the lower parts 31b and 32b becomes a gap 91, forming return channels X2 and X3.

[0029] Figure 10 is a top view of the internal structure of the second phase arc extinguishing chamber of a switch according to a second modification of Embodiment 2. Figure 11 is a cross-sectional view of the internal structure of the second phase arc extinguishing chamber of a switch according to a second modification of Embodiment 2. Figure 11 shows a cross-section of the second phase arc extinguishing chamber 21b along the line XI-XI in Figure 10. In the switch 1 according to the second modification of Embodiment 2, grooves 33b and 34b extending in the Y direction are formed in each of the insulating members 271b and 272b. In the switch 1 according to the second modification of Embodiment 2, the internal space of the grooves 33b and 34b becomes a gap 91, forming return channels X2 and X3.

[0030] Thus, the return channels X2 and X3 only need to be separated from the return channel X1 by being composed of at least one of the surfaces of the side portion 261b or side portion 262b of the grid 26b and the insulating member 271b or insulating member 272b.

[0031] The switch 1 according to Embodiment 2 includes a return channel X1 through which the hot gas flow generated between the movable contact 25b and the fixed contact 24b flows in the +Y direction, and return channels X2 and X3 through which the hot gas flow, whose direction has been changed by the connecting portion 263b, flows in the -Y direction. Therefore, it is possible to strengthen the hot gas flow generated between the movable contact 25b and the fixed contact 24b and the hot gas flow returned around the movable contact 25b and the fixed contact 24b, while suppressing mutual weakening. Accordingly, in addition to the same effects as the switch 1 according to Embodiment 1, the switch 1 according to Embodiment 2 can further extend the arc to the grid 26b and break it, thereby completing arc interruption at a faster speed.

[0032] Furthermore, the hot gas does not necessarily need to branch in the ±X direction at the connecting section 263b. Therefore, the same effect can be obtained by flowing the hot gas through at least one of the return channels X2 and X3.

[0033] Embodiment 3. Figure 12 is a top view of the internal structure of the second phase arc extinguishing chamber of the switch according to Embodiment 3. The switch 1 according to Embodiment 3 differs from the switch 1 according to Embodiment 2 in that the insulating members 271b and 272b are installed such that the wall surfaces 291b and 292b facing the fixed contact 24b are inclined with respect to the side surfaces 261b and 262b of the grid 26b.

[0034] As shown in Figure 12, in the switch 1 according to Embodiment 3, the insulating member 271b is arranged such that the wall surface 291b and the side surface 261b form an angle θ in the XY plane, and similarly, the insulating member 272b is arranged such that the wall surface 292b and the side surface 262b form an angle θ' in the XY plane. Here, the angles θ and θ' do not necessarily have to be the same size.

[0035] Furthermore, similar to the switch 1 in the modified embodiment 2, the insulating members 271b and 272b can also be configured to have lower portions 31b and 32b.

[0036] In the switch 1 according to Embodiment 3, the wall surfaces 291b and 292b of the insulating members 271b and 272b that face the fixed contact 24b are inclined with respect to the side surfaces 261b and 262b of the grid 26b. As the insulating members 271b and 272b approach the connecting portion 263b along the Y direction, they move closer to the movable contact 25b and the fixed contact 24b, thus increasing the flow velocity of the hot gas flowing through the return channel X1. As a result, the switch 1 according to Embodiment 3 strengthens the force that drives the arc with the hot gas flow, quickly extending the arc to the grid 26b and breaking it, thereby enabling faster arc interruption.

[0037] Embodiment 4. Figure 13 is a top view of the internal structure of the second phase arc extinguishing chamber of the switch according to Embodiment 4. In the switch 1 according to Embodiment 4, insulating members 271b and 272b are installed such that the area of ​​the gas outlet surface a of the return channels X2 and X3 is smaller than the area of ​​the gas inlet surface b from the return channel X1 to the return channels X2 and X3. Here, the area of ​​the gas outlet surface a and the area of ​​the gas inlet surface b of the return channels X2 and X3 do not necessarily have to be the same; it is sufficient that the area of ​​the gas outlet surface a < the area of ​​the gas inlet surface b holds true for each of the return channels X2 and X3.

[0038] Figure 14 is a perspective view of the internal structure of the second phase arc extinguishing chamber of a switch according to a modified example of Embodiment 4. In Figure 14, the grid 26b is not shown. The insulating member 271b of the switch 1 according to the modified example of Embodiment 4, similar to the insulating member 271b of the switch 1 according to the second modified example of Embodiment 2, has a groove 33b formed in the insulating member 271b that extends in the first direction, with a gap 91 inside to form a return channel X2. In the switch 1 according to the modified example of Embodiment 4, the cross-sectional area of ​​the groove 33b increases as it approaches the connecting portion 263b. Although not shown in Figure 14, similar to the insulating member 272b of the switch 1 according to the second modified example of Embodiment 2, the insulating member 272b has a groove 34b similar to the groove 33b of the insulating member 271b, with a gap 91 inside the groove 34b to form a return channel X3. Therefore, in the modified switch 1 of Embodiment 4, the area of ​​the gas outlet surface a from the return channels X2 and X3 is smaller than the area of ​​the gas inlet surface b from the return channel X1 to the return channels X2 and X3.

[0039] Furthermore, similar to the switch 1 according to the first modified example of Embodiment 2, it is also possible to have a configuration in which the insulating members 271b and 272b have lower parts 31b and 32b. In a configuration in which the insulating members 271b and 272b have lower parts 31b and 32b, the height of the lower parts 31b and 32b decreases as it approaches the connecting part 263b along the Y direction, so that the area of ​​the gas outlet surface a of the return channels X2 and X3 is smaller than the area of ​​the gas inlet surface b from the return channel X1 to the return channels X2 and X3. Alternatively, the height difference between the side parts 261b and 262b of the grid 26b and the lower parts 31b and 32b of the insulating members 271b and 272b increases as it approaches the connecting part 263b along the Y direction, so that the area of ​​the gas outlet surface a of the return channels X2 and X3 is smaller than the area of ​​the gas inlet surface b from the return channel X1 to the return channels X2 and X3. Furthermore, the dimensions of the recirculation channels X2 and X3 in the X direction may increase as they approach the connecting portion 263b along the Y direction, so that the area of ​​the gas outlet surface a of the recirculation channels X2 and X3 is smaller than the area of ​​the gas inlet surface b from the recirculation channel X1 to the recirculation channels X2 and X3.

[0040] In the switch 1 according to Embodiment 4, the area of ​​the gas outlet surface a of the return channels X2 and X3 is smaller than the area of ​​the gas inlet surface b, and the return channels X2 and X3 are narrowed in the flow direction, so the flow velocity blown onto the movable contact 25b and the fixed contact 24b can be increased. For this reason, the switch 1 according to Embodiment 4 can further enhance the arc cooling effect compared to the switch 1 according to Embodiments 1 to 3, and can more reliably shut off the arc.

[0041] Embodiment 5. Figure 15 is a top view of the internal structure of the second phase arc extinguishing chamber of the switch according to Embodiment 5. The switch 1 according to Embodiment 5 differs from the switch 1 according to Embodiment 4 in that it is equipped with gas blowing members 281b and 282b. The gas blowing members 281b and 282b are installed adjacent to the ends of the side portions 261b and 262b that are opposite to the side connected to the connecting portion 263b. The surfaces of the gas blowing members 281b and 282b that face the fixed contact 24b are curved surfaces that approach the fixed contact 24b as they move away from the connecting portion 263b.

[0042] By providing the gas-blowing members 281b and 282b on the gas outlet surface a side of the return channels X2 and X3, a return channel X4 is formed in the space between the insulating member 271b and the gas-blowing member 281b, and a return channel X5 is formed in the space between the insulating member 272b and the gas-blowing member 282b.

[0043] When the contacts are opened, a portion of the hot gas generated with the arc between the movable contact 25b and the fixed contact 24b flows from either the movable contact 25b or the fixed contact 24b toward the grid 26b. The hot gas that collides with the connecting portion 263b branches into ±X directions, which are perpendicular to the Z direction, the direction of movement of the movable contact 22b. The hot gas travels along the inner surface of the grid 26b and flows through the recirculation channels X2 and X3 in the -Y direction, opposite to the gas flow of the hot gas in recirculation channel X1. The hot gas that has flowed through recirculation channels X2 and X3 has its direction of travel changed by the gas blowing members 281b and 282b, and the gas flow of hot gas flows toward the movable contact 25b and the fixed contact 24b, respectively, into recirculation channels X4 and X5, and the hot gas is blown onto the movable contact 25b and the fixed contact 24b.

[0044] The switch 1 according to Embodiment 5 can efficiently blow hot gas onto the movable contact 25b and the fixed contact 24b, thereby enhancing the arc cooling effect and enabling more reliable arc interruption.

[0045] Embodiment 6. The switch 1 according to Embodiment 6 differs from the switch 1 according to Embodiment 2 in that the structure of the grid 26b is different. Figure 16 is a perspective view of the grid of the switch 1 according to Embodiment 6. In the switch 1 according to Embodiment 6, at least one through hole 264b is provided on at least one of the side portions 261b and 262b of the grid 26b, and the inner space and the outer space of the grid 26b are connected via the through hole 264b. Otherwise, it is the same as the switch 1 according to Embodiment 2.

[0046] By providing at least one through-hole 264b in at least one of the side portions 261b and 262b, a portion of the hot gas flowing through the return channels X2 and X3 is discharged outside the return channels X2 and X3 through the through-hole 264b.

[0047] If the hot gas flow stagnates in the return channels X2 and X3, the inflow of hot gas from the return channel X1 will also stagnate, weakening the arc drive by the hot gas flow in the +Y direction through the return channel X1. Furthermore, the stagnation of the gas flow inflow from the return channel X1 to the return channels X2 and X3 reduces the gas flow that circulates around the fixed contact 24b and the movable contact 25b. The switch 1 according to Embodiment 6 can discharge the hot gas flowing through the return channels X2 and X3 to the outside of the return channels X2 and X3 at an appropriate rate, so that the hot gas does not stagnate in the return channels X2 and X3 and circulates around the movable contact 25b and the fixed contact 24b. Therefore, in addition to the effects of the switch 1 according to Embodiments 1 to 5, the switch 1 according to Embodiment 6 can increase the recirculation efficiency, which represents the proportion of hot gas generated between the movable contact 25b and the fixed contact 24b that recirculates around the movable contact 25b and the fixed contact 24b, thereby enabling more reliable arc interruption.

[0048] Embodiment 7. The switch 1 according to Embodiment 7 differs from the switch 1 according to Embodiment 3 in that the structure of the grid 26b is different. Figure 17 is a perspective view of the internal structure of the second phase arc extinguishing chamber of the switch according to Embodiment 7. In the switch 1 according to Embodiment 7, multiple grids 26b are stacked in the direction of movement of the movable contact 22b. Here, the grids 26b of each layer are not electrically connected to each other. Otherwise, it is the same as the internal structure of the second phase arc extinguishing chamber 21b of the switch 1 according to Embodiment 5.

[0049] Similar to Embodiment 1, the arc generated between the movable contact 25b and the fixed contact 24b is pulled by the stacked grids 26b, connecting the movable contact 25b and the fixed contact 24b with the connecting portion 263b of one of the grids 26b in between. Subsequently, each grid 26b is electrically connected, and the arc is divided by the grids 26b with the movable contact 22b and the fixed contact 23b at both ends.

[0050] In the switch 1 according to Embodiment 7, if an arc is drawn into any of the multiple grids 26b, the drawn-in arc can be divided among the multiple grids 26b, thereby increasing the arc voltage and enabling more reliable arc interruption.

[0051] Although Embodiments 1 to 7 described contact switches with one pair of contacts per phase, the same can be implemented for contact switches with multiple pairs of contacts per phase, and this does not limit their range of use.

[0052] The configurations shown in the above embodiments are merely examples of the content, and can be combined with other known technologies. It is also possible to omit or modify parts of the configuration without departing from the gist of the invention. [Explanation of symbols]

[0053] 1 Switch, 1A Contact section, 1B Switching mechanism section, 1C Relay section, 21a First phase arc extinguishing chamber, 21b Second phase arc extinguishing chamber, 21c Third phase arc extinguishing chamber, 22b Movable contact, 23a, 23b, 23c Fixed contact, 23d, 23e, 23f Fixed terminal, 24b Fixed contact, 25b Movable contact, 26b Grid, 31b, 32b Bottom section, 33b, 34b Groove, 91 Gap, 221b Drive shaft, 231a, 231b, 231c Power supply side terminal, 231d, 231e, 231f Load side terminal, 261b, 262b Side section, 263b Connecting section, 264b Through hole, 271b, 272b Insulating member, 281b, 282b Gas spraying components, 291b, 292b, wall surface.

Claims

1. Fixed contacts and A movable contact is installed on a rod-shaped movable contact that rotates, and which contacts and separates from the fixed contact as the movable contact rotates. A metal grid is positioned opposite the fixed contact in a second direction, which is perpendicular to the first direction, which is the direction of movement of the movable contact, and is aligned with the longitudinal direction of the movable contact. The grid and the fixed contact are provided with at least one insulating member installed between them, The grid has two side surfaces facing each other across the movable contact in a third direction which is perpendicular to each of the first and second directions. The insulating member is installed between at least one of the two side portions and the fixed contact. The grid is characterized in that it returns the gas flow that flows from the movable contact and the fixed contact toward the grid in the second direction, which occurs between the movable contact and the fixed contact during an opening operation in which the fixed contact separates from the movable contact, back to the area around the movable contact and the fixed contact.

2. The grid has a connecting portion that faces the fixed contact in the second direction and connects the two side portions together, The insulating member exposes at least a portion of the connecting portion of the grid when viewed from the position of the fixed contact, The switch according to claim 1, characterized in that the dimension of the connecting portion in the first direction is greater than or equal to the dimension in the second direction.

3. The switch according to claim 2, characterized in that a gap is formed between the insulating member and the side portion facing the insulating member.

4. The switch according to claim 3, wherein a return channel is formed by the gap through which the gas flow flows in the opposite direction to the direction from the fixed contact toward the connecting portion in the second direction, and the cross-sectional area of ​​the gap at the end closer to the connecting portion in the second direction is larger than the cross-sectional area at the end farther from the connecting portion.

5. The switch according to claim 3, wherein the insulating member has a lower portion where the distance from the fixed contact in the first direction is shorter than the distance between the end of the side portion of the opposing side portion and the fixed contact in the first direction, and the gap is formed above the lower portion.

6. The switch according to claim 5, characterized in that the height difference, which is the distance between the lower portion and the end face of the insulating member in the first direction, increases as it approaches the connecting portion along the second direction.

7. The switch according to claim 5, characterized in that the dimension of the insulating member in the first direction at the lower portion increases as it approaches the connecting portion along the second direction.

8. The switch according to claim 3, characterized in that the insulating member has a groove extending in the second direction formed on the surface facing the side portion, and the space inside the groove forms the gap.

9. The switch according to claim 8, characterized in that the dimension of the gap in the first direction increases as it approaches the connecting portion along the second direction.

10. The switch according to claim 2, characterized in that the insulating member is installed such that the wall surface facing the fixed contact approaches the fixed contact in the third direction as it approaches the connecting portion in the second direction.

11. The switch according to claim 2, characterized in that the grid includes a gas blowing member that changes the direction of travel of the gas flow along the side portion and blows it onto the fixed contact.

12. The switch according to claim 2, characterized in that the grid has through holes formed in the side portions that connect the space enclosed by the connecting portion and the side portions with the outside of the space.

13. The switch according to any one of claims 1 to 12, characterized in that a plurality of grids are stacked along the first direction.

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