electromagnetic contactor

Abstract

To provide an electromagnetic contactor that effectively utilizes an arc-extinguishing space in extending an arc generated at a contact part to improve heat insulation performance.SOLUTION: An electromagnetic contactor 11 comprises a pair of fixed contacts 31, a movable contact 32, a permanent magnet 25, and an arc runner 26. The pair of fixed contacts 31 have fixed contacts 35 formed. The movable contact 32 has a pair of movable contacts 36 formed, and is displaced in a predetermined direction to let the movable contact 36 contact and leave the fixed contact 35. The permanent magnet 25 applies an external magnetic field φ to a contact part 21, composed of the fixed contact 35 and movable contact 36, in a direction orthogonal to the displacing direction of the movable contact 32. The arc runner 26 is a conductor which is electrically connected to the fixed contact 31 in a room where the contact part 21 is arranged, and extends in a direction orthogonal to an external magnetic field φ when viewed from the displacing direction of the movable contact 32.SELECTED DRAWING: Figure 9

Description

[Technical Field]

[0001] The present invention relates to an electromagnetic contactor. [Background technology]

[0002] In the electromagnetic contactor disclosed in the cited document 1, the arc generated at the contact point is stretched laterally of the case by the Lorentz force corresponding to the external magnetic field of the permanent magnet, thereby improving the breaking performance of the contact point. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2011-204472 Summary of the Invention [Problem to be solved by the invention]

[0004] Simply stretching the arc generated at the contact point laterally does not allow for effective use of the arc-extinguishing space, leaving room for improvement in terms of breaking performance. An object of the present invention is to effectively utilize the arc extinguishing space when extending the arc generated at the contact portion in an electromagnetic contactor, thereby improving the interruption performance. [Means for solving the problem]

[0005] An electromagnetic contactor according to one aspect of the present invention includes a pair of fixed contacts, a movable contact, a permanent magnet, and an arc runner. The pair of fixed contacts are formed with fixed contacts. The movable contactor is formed with a pair of movable contacts, and displaces along a predetermined direction to bring the movable contacts into contact with and separate from the fixed contacts. The permanent magnet applies an external magnetic field to a contact portion formed by the fixed contacts and the movable contact in a direction perpendicular to the displacement direction of the movable contact. The arc runner is a conductor electrically connected to the fixed contacts within a chamber in which the contact portion is disposed and extending in a direction perpendicular to the external magnetic field as viewed from the displacement direction of the movable contact. [Effects of the Invention]

[0006] According to the present invention, when an arc occurs at the contact point, a Lorentz force acts in a direction perpendicular to the external magnetic field, causing the fixed contact side of the arc to move along the arc runner. Because the arc is tilted relative to the displacement direction of the movable contact, it is stretched not only in a direction perpendicular to the displacement direction of the movable contact, but also in the displacement direction of the movable contact. This makes effective use of the arc-extinguishing space and improves breaking performance. [Brief explanation of the drawings]

[0007] [Figure 1] FIG. 1 is an isometric view of an electromagnetic contactor. [Figure 2] FIG. [Figure 3] FIG. 2 is a cross-sectional view (cross section AA) of the electromagnetic contactor. [Figure 4] FIG. 3 is a cross-sectional view of an electromagnetic contactor (cross section BB). [Figure 5] FIG. 2 is a cross-sectional view of an electromagnetic contactor (cross-section CC). [Figure 6] FIG. 2 is a cross-sectional view of an electromagnetic contactor (cross section DD). [Figure 7] FIG. 1 is an isometric cross-sectional view of a capsule case. [Figure 8] FIG. 1 is an isometric cross-sectional view of a capsule case with a permanent magnet fixed thereto. [Figure 9] FIG. 2 is a partially enlarged cross-sectional view (cross section CC) of the electromagnetic contactor. [Figure 10] FIG. 2 is a cross-sectional view of an electromagnetic contactor (cross section DD). [Figure 11] FIG. [Figure 12] 10 is a cross-sectional view (cross section DD) of an electromagnetic contactor according to a second embodiment. FIG. [Figure 13] 10 is a partially enlarged cross-sectional view (cross-section CC) of an electromagnetic contactor according to a second embodiment. FIG. [Figure 14] 10 is a cross-sectional view (cross-section CC) of an electromagnetic contactor according to a third embodiment. FIG. [Figure 15] FIG. 1 is an isometric cross-sectional view of a capsule case. [Figure 16] FIG. 1 is an isometric cross-sectional view of a capsule case with an arc runner fixed thereto. DETAILED DESCRIPTION OF THE INVENTION

[0008] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the drawings are schematic and may differ from the actual product. Furthermore, the following embodiments exemplify devices and methods for embodying the technical concept of the present invention, and are not intended to limit the configuration to those described below. In other words, the technical concept of the present invention can be modified in various ways within the technical scope described in the claims.

[0009] First Embodiment "composition" In the following description, the three mutually orthogonal directions will be referred to as the vertical direction, the width direction, and the depth direction for the sake of convenience. 1 is an isometric view of an electromagnetic contactor. (a) in the figure shows the electromagnetic contactor 11 as seen from one side in the vertical direction, one side in the width direction, and from the front in the depth direction, and (b) in the figure shows the electromagnetic contactor 11 as seen from the other side in the vertical direction, one side in the width direction, and from the front in the depth direction. The electromagnetic contactor 11 is a sealed high-voltage contactor that opens and closes the main circuit using electromagnetic force. FIG. 2 is a plan view of the electromagnetic contactor. Here, the electromagnetic contactor 11 is shown as seen from the front side in the depth direction.

[0010] FIG. 3 is a cross-sectional view (AA cross section) of the electromagnetic contactor. Here, the cross section AA of the electromagnetic contactor 11 shown in FIG. 2, which is along the vertical and depth directions and passes through the center in the width direction, is shown as viewed from one side in the width direction. FIG. 4 is a cross-sectional view of the electromagnetic contactor (cross-section BB). Here, the cross section BB of the electromagnetic contactor 11 shown in FIG. 2, which is taken along the width direction and depth direction and passes through the center in the vertical direction, is shown as viewed from one side in the vertical direction. FIG. 5 is a cross-sectional view (cross-section CC) of the electromagnetic contactor. Here, the state where the CC cross section along the width direction and depth direction of the electromagnetic contactor 11 shown in FIG. 2 is viewed from one side in the vertical direction is shown.

[0011] First, we will explain the basic configuration of the electromagnetic contactor 11. The electromagnetic contactor 11 includes a sealed container 12 made of electrically insulating resin, and the sealed container 12 includes a capsule case 13 and a capsule cover 14. The capsule case 13 has a generally rectangular box shape with both vertical and widthwise ends and a front side in the depth direction closed and an open rear side in the depth direction. The capsule cover 14 has a generally rectangular box shape with both vertical and widthwise ends and a front side in the depth direction closed and an open front side in the depth direction. The capsule case 13 and the capsule cover 14 fit together at their open ends and are fastened together with tapping screws (not shown). The sealed container 12 contains a contact portion 21 and an electromagnet portion 22. Inside the sealed container 12, the front side in the depth direction where the contact portion 21 is located forms an arc-extinguishing chamber 23.

[0012] A metal pipe 15 is provided in the capsule cover 14, penetrating one of the side walls in the vertical direction. The pipe 15 serves as an inlet for charging pressurized interrupting gas such as hydrogen or nitrogen, connecting the inside and outside, but is sealed by being crushed at the tip end after charging. The entire outer surface of the sealed container 12 is gas-barrier coated with a laminated film of clay crystals. Specifically, the interlayer ions of purified smectite are replaced and bound together with an organic binder such as PVA (polyvinyl alcohol) or water-soluble nylon, creating a labyrinth effect that prevents the permeation of gas molecules such as hydrogen and nitrogen. The laminated film is layered in the thickness direction, with a thickness of, for example, 2 μm. The gas-barrier coating is achieved, for example, by spraying a coating liquid into a mist and applying it to the sealed container 12, followed by baking at a temperature of, for example, 150°C or higher, at which the interlayer ions are incorporated into the clay crystals.

[0013] The electromagnetic contactor 11 includes a pair of fixed contacts 31 and a movable contact 32 . The pair of fixed contacts 31 are electrode types formed of a conductive metal in a generally cylindrical shape extending in the depth direction, and are arranged vertically spaced apart. The front side of the fixed contact 31 in the depth direction is exposed to the outside of the sealed container 12, and the rear side in the depth direction is disposed inside the sealed container 12. Each fixed contact 31 has a screw hole 33 formed in its front end surface in the depth direction, and a terminal screw is fitted into the screw hole 33, so that one side is connected to the primary side of the main circuit and the other side is connected to the secondary side of the main circuit. A plate-shaped insulating barrier 16 is formed on the top surface of the capsule case 13 between the fixed contacts 31, extending in the width and depth directions. A fixed contact 35 is formed on the rear end surface in the depth direction of the fixed contact 31.

[0014] The pair of fixed contacts 31 are integrated through the ceiling of the capsule case 13 by insert molding. Specifically, micron-sized irregularities are formed on the surface of the fixed contacts 31 by chemical etching, and then insert molding is performed. This allows molten resin to penetrate the irregularities and solidify, bonding the metal and resin at the interface level, creating a complex bond due to the labyrinth effect and preventing leakage of gas molecules such as hydrogen and nitrogen. An example of metal surface treatment technology is "AMALPHA" (registered trademark) by MEC Corporation. The pipe 15 that penetrates the side wall of the capsule cover 14 is also insert molded using a similar method.

[0015] The movable contactor 32 is made of a conductive metal, extends vertically, and is formed in a flat plate shape along the vertical and width directions, and is disposed further back in the depth direction than the pair of fixed contactors 31. The movable contactor 32 has movable contacts 36 formed on both vertical ends of its front surface in the depth direction. When the movable contactor 32 is displaced toward the back in the depth direction, the movable contacts 36 are separated from the fixed contacts 35, and when the movable contactor 32 is displaced toward the front in the depth direction, the movable contacts 36 are brought into contact with the fixed contacts 35. The contact section 21 is composed of the fixed contacts 35 and the movable contacts 36.

[0016] The movable contactor 32 is supported by a contact support 41. The contact support 41 includes a base 42, a pressing member 43, and a contact spring 44. The base 42 is made of electrically insulating resin. As shown in FIG. 4 , the pressing member 43 is formed in a roughly C-shape that opens toward the rear in the depth direction, like a lip channel steel when viewed vertically, and is fixed to the front side of the base 42 in the depth direction. The movable contactor 32 and the contact spring 44 are arranged inside the pressing member 43. The contact spring 44 is a compression coil spring and is interposed between the base 42 and the movable contactor 32, biasing the movable contactor 32 toward the front side in the depth direction. In this way, the contact spring 44 elastically supports the movable contactor 32, thereby maintaining a constant contact pressure of the contact portion 21.

[0017] The electromagnet unit 22 is housed at the rear side in the depth direction of the sealed container 12, and switches the opening and closing of the contact unit 21. The electromagnet unit 22 includes a spool 51, a sliding collar 52, a movable plunger 53, an armature 54, a yoke 55, a plunger ring 56, a back spring 57, a permanent magnet 58, and an auxiliary yoke 59. The spool 51 is a winding frame made of an electrically insulating resin, and has a cylindrical winding shaft 61 extending in the depth direction around which a coil 62 is wound. The sliding collar 52 is formed into a cylindrical shape from an electrically insulating resin, and is inserted into the inside of the winding shaft 61 from the rear side in the depth direction and fitted therein.

[0018] The movable plunger 53 is formed as a cylindrical movable core extending in the depth direction, and is guided for axial movement by fitting inside the sliding collar 52. The movable plunger 53 is connected to the base 42 of the contact support 41 via a connecting spring 63 on the front side in the depth direction. The armature 54 is a disk-shaped yoke extending in the vertical and width directions, and is fixed to the end of the movable plunger 53 on the far side in the depth direction. The pair of yokes 55 are plate-shaped iron yokes, and are fixed one on each of the longitudinal sides of the spool 51. When viewed in the width direction, the yoke 55 is formed in a roughly U-shape that opens inward in the longitudinal direction, and covers the outer side of the coil 62 in the longitudinal direction and both end sides in the depth direction.

[0019] Plunger ring 56 is a cylindrical yoke extending in the depth direction, is inserted into and fits into the inside of winding shaft 61 from the front side in the depth direction, and is fixed to the upper piece on the front side in the depth direction of yoke 55. The inner diameter of plunger ring 56 is larger than the outer diameter of movable plunger 53 and is set so as to maintain a predetermined clearance with respect to movable plunger 53. The back spring 57 is a compression coil spring that is inserted into the movable plunger 53 while being sandwiched between the armature 54 and the plunger ring 56, and urges the movable plunger 53 toward the rear in the depth direction relative to the spool 51. The permanent magnet 58 is a rectangular flat plate with a round hole formed through it in the depth direction. It is fitted into the depth side of the spool 51, contacts the depth side lower piece of the yoke 55, and is arranged to surround the armature 54. The auxiliary yoke 59 is a flat plate-shaped yoke, and is attached to the end surface of the permanent magnet 58 on the far side in the depth direction.

[0020] As described above, in a non-excited state where no current is flowing through the coil 62, the magnetic force of the permanent magnet 58 and the repulsive force of the back spring 57 displace the movable plunger 53 toward the rear in the depth direction, and the armature 54 is attracted to the auxiliary yoke 59. At this time, the contact support 41 also displaces toward the rear in the depth direction, so that the pair of fixed contacts 35 and the movable contact 36 are separated from each other, and the contact portion 21 opens (disconnected state). On the other hand, when the coil 62 is energized and excited, the armature 54 is attracted to the lower part of the yoke 55, and the movable plunger 53 is displaced toward the front in the depth direction against the magnetic force of the permanent magnet 58 and the repulsive force of the back spring 57. At this time, the contact support 41 also displaces toward the front in the depth direction, so that the movable contact 36 comes into contact with each of the pair of fixed contacts 35, and the contact unit 21 is closed (closed state).

[0021] Next, a structure for extending the arc generated when the contact portion 21 is opened by magnetic drive will be described. FIG. 6 is a cross-sectional view (cross section DD) of the electromagnetic contactor. Here, a DD cross section along the vertical and width directions of the electromagnetic contactor 11 shown in Fig. 3 is shown as viewed from the rear side in the depth direction. The electromagnetic contactor 11 includes a permanent magnet 25 and an arc runner 26. The permanent magnets 25 are formed in the shape of rectangular flat plates extending in the width and depth directions, and are provided one on each side of the two vertically aligned contact portions 21 so as to face each other, applying an external magnetic field φ in the vertical direction to the contact portions 21. The two permanent magnets 25 have opposite poles facing each other, with one having its south pole facing the inside in the vertical direction and the other having its north pole facing the inside in the vertical direction. In this case, an external magnetic field φ is generated from one permanent magnet 25 toward the other permanent magnet 25, as indicated by the dashed arrow.

[0022] Here, the other fixed contact 31 in the vertical direction is the primary side, and one fixed contact 31 in the vertical direction is the secondary side. Therefore, at the other contact portion 21 in the vertical direction, the current of arc A generated during breaking flows from the fixed contact 31 toward the movable contact 32, i.e., toward the back side in the depth direction. As shown by the block arrow, a Lorentz force F acts on the other arc A in the vertical direction due to the external magnetic field φ, which acts toward the other side in the width direction. At one contact portion 21 in the vertical direction, the current of arc A generated during breaking flows from the movable contact 32 toward the fixed contact 31, i.e., toward the front side in the depth direction. As shown by the block arrow, a Lorentz force F acts on the one arc A in the vertical direction due to the external magnetic field φ, which acts toward the other side in the width direction.

[0023] Next, the fixing of the permanent magnet 25 will be described. FIG. 7 is an isometric cross-sectional view of the capsule case. Here, cross sections along the vertical and width directions of the capsule case 13 before the permanent magnets 25 are fixed are shown, as viewed from the far side in the depth direction, one side in the vertical direction, and the other side in the width direction. Inside the capsule case 13, one storage section 17 for storing the permanent magnets 25 is formed on each side in the vertical direction. The storage section 17 is formed in a pocket shape that is closed on both sides in the vertical direction, both sides in the width direction, and the front side in the depth direction, and is open on the far side in the depth direction. One permanent magnet 25 is stored in each storage section 17.

[0024] FIG. 8 is an isometric cross-sectional view of a capsule case with a permanent magnet fixed thereto. Here, cross sections along the vertical and width directions of the capsule case 13 after the permanent magnet 25 has been fixed are shown, as viewed from the far side in the depth direction, one side in the vertical direction, and the other side in the width direction. The permanent magnet 25 is fixed to the storage section 17 by adhesive 27, and is arranged vertically inward within the storage section 17. The adhesive 27 filled and solidified in the storage section 17 covers the permanent magnet 25 all the way to the far side in the depth direction, as shown in Fig. 3. The permanent magnet 25 may be inserted into the storage section 17 first and then the adhesive 27 may be injected, or the adhesive 27 may be injected first and then the permanent magnet 25 may be inserted.

[0025] Arc runner 26 is made of a conductive metal, extends in the width direction, and is formed in the shape of a flat plate aligned in the width direction and the vertical direction. Arc runner 26 is electrically connected to fixed contactor 31 inside arc extinguishing chamber 23. Arc runner 26 is preferably made of the same material as fixed contactor 31. As shown in FIG. 5 , arc runner 26 has a circular hole 28 (through hole) formed in the center in the width direction, penetrating in the depth direction, and fixed contactor 31 is fitted into circular hole 28. Arc runner 26 and fixed contactor 31 are brazed together. Arc runner 26 is integrated with fixed contactor 31 into the ceiling of capsule case 13 by insert molding. The insert molding method is the same as that for fixed contactor 31.

[0026] <<Action and Effect>> Next, the main effects of the first embodiment will be described. The electromagnetic contactor 11 includes a pair of fixed contacts 31, a movable contact 32, a permanent magnet 25, and an arc runner 26. The pair of fixed contacts 31 are formed with fixed contacts 35. The movable contact 32 is formed with a pair of movable contacts 36, and moves in a predetermined direction to bring the movable contacts 36 into contact with and separate from the fixed contacts 35. The permanent magnet 25 applies an external magnetic field φ to a contact unit 21 formed by the fixed contacts 35 and the movable contact 36 in a direction perpendicular to the displacement direction of the movable contact 32. The arc runner 26 is electrically connected to the fixed contacts 31 in a room in which the contact unit 21 is located, and is a conductor extending in a direction perpendicular to the external magnetic field φ when viewed from the displacement direction of the movable contact 32.

[0027] FIG. 9 is a partially enlarged cross-sectional view (cross-section CC) of the electromagnetic contactor. 2 is shown, viewed from one side in the vertical direction, with a CC cross section along the width and depth directions, and a partially enlarged view of the contact portion 21. In the arc extinguishing chamber 23, an arc A generated at the secondary side contact portion 21 by interruption is indicated by a thick dotted arrow, and A1 to A3 indicate changes over time. A1 is the initial arc, and its starting point is at the center of the width direction of the movable contact 32 and its ending point is at the center of the width direction of the fixed contact 31, so that the arc A1 extends towards the front in the depth direction. Since an external magnetic field φ directed in one longitudinal direction is applied to the arc A1, a Lorentz force F1 acts in one width direction according to Fleming's left-hand rule.

[0028] A2 is an intermediate arc stretched by Lorentz force F1, with its starting point moving in one direction in the width direction of the movable contact 32 and its ending point moving from the fixed contact 31 to the arc runner 26. Therefore, arc A2 extends toward the front in the depth direction and toward one direction in the width direction. Since an external magnetic field φ directed in one direction in the vertical direction is applied to arc A2, Lorentz force F2 acts in one direction in the width direction and toward the back in the depth direction according to Fleming's left-hand rule. A3 is a later arc that is further stretched by Lorentz force F2, with its starting point moving to the side of the movable contact 32 and its ending point moving toward one side in the width direction of the arc runner 26. Arc A3 is curved greatly so as to be convex toward one side in the width direction and the far side in the depth direction, and extends toward one side in the width direction and the far side in the depth direction, then toward the other side in the width direction and the near side in the depth direction.

[0029] When an arc A1 is generated at the contact portion 21, a Lorentz force F1 acts in a direction perpendicular to the external magnetic field φ, causing the fixed contact 31 side of the arc A to move along the arc runner 26. Because the arc A2 is tilted relative to the displacement direction of the movable contact 32, the Lorentz force F2 is also tilted relative to the displacement direction of the movable contact 32. As a result, the arc A3 is stretched not only in a direction perpendicular to the displacement direction of the movable contact 32 but also in the displacement direction of the movable contact 32. This effectively utilizes the width and depth of the arc-extinguishing space. Increasing the arc voltage in this way extinguishes the arc A and restores insulation at the contact portion 21. While the secondary-side contact portion 21 has been described above, the same applies to the primary-side contact portion 21. By sufficiently stretching the arc A generated at the contact portion 21 in this way, the arc-breaking performance can be improved while preventing the arc-extinguishing chamber 23 from becoming too large.

[0030] The electromagnetic contactor 11 includes a sealed container 12. The sealed container 12 has a contact portion 21 disposed therein and is made of resin and filled with a blocking gas. By using a resin sealed container 12 in this way, it is possible to ensure electrical insulation while reducing the size and weight, thereby improving design flexibility. The fixed contactor 31 and the arc runner 26 are insert-molded into the sealed container 12. This allows both the fixed contactor 31 and the arc runner 26 to be integrated into the sealed container 12 at the same time. This eliminates the need for a subsequent process of fixing the arc runner 26, simplifying downstream assembly processes. Furthermore, because the metal and resin are joined at the interface level, the arc runner 26 can be firmly fixed.

[0031] The sealed container 12 includes a storage section 17. The storage section 17 is separated from the inside of the arc extinguishing chamber 23 in which the contact section 21 is arranged, and stores a permanent magnet 25. The permanent magnet 25 is susceptible to thermal demagnetization, which is a decrease in magnetic flux density, due to heating. However, because the permanent magnet 25 is housed and isolated in the storage section 17, thermal demagnetization due to the arc A at the time of breaking can be prevented. The permanent magnet 25 is fixed to the storage portion 17 by adhesive 27. This allows the permanent magnet 25 to be fixed inexpensively and easily. The movable contactor 32 extends in a direction perpendicular to the displacement direction of the movable contactor 32. The permanent magnet 25 applies an external magnetic field φ along the longitudinal direction of the movable contactor 32. The arc runner 26 extends in the lateral direction of the movable contactor 32. Inside the sealed container 12, it is easy to ensure arc-extinguishing space on both sides of the lateral direction of the movable contactor 32. Therefore, by extending the arc runner 26 in the lateral direction of the movable contactor 32, it is possible to ensure sufficient arc-extinguishing space and improve breaking performance while preventing the arc-extinguishing chamber 23 from becoming too large.

[0032] The arc runner 26 extends toward both one side and the other side of the short side of the movable contactor 32. This allows the arc A to be extended in the same way when a current flows in the reverse direction as when a current flows in the forward direction, improving the interruption performance. For example, in an electromagnetic contactor 11 used in a charging circuit of an electric vehicle (EV), power may be supplied from the vehicle side to the outside, and at this time, a current flows through the electromagnetic contactor 11 in the opposite direction to that during charging. Therefore, it is required that the arc A be extended in the same way whether the current flows in the forward direction or the reverse direction.

[0033] FIG. 10 is a cross-sectional view (cross section DD) of the electromagnetic contactor. Here, the DD cross section of the electromagnetic contactor 11 shown in FIG. 3 along the vertical and width directions is shown, as viewed from the rear in the depth direction. The current flows in the opposite direction to the state shown in FIG. 6. That is, at one of the vertical contact portions 21, the current of the arc A generated during interruption flows from the fixed contact 31 to the movable contact 32, i.e., toward the rear in the depth direction. A Lorentz force F acts on one of the vertical arcs A in the other width direction due to the external magnetic field φ. At the other vertical contact portion 21, the current of the arc A generated during interruption flows from the movable contact 32 to the fixed contact 31, i.e., toward the front in the depth direction. A Lorentz force F acts on the other arc A in the other width direction due to the external magnetic field φ. In this way, even when the current flows in the reverse direction, the arc A can be elongated, improving the interruption performance in the same way as when the current flows in the forward direction.

[0034] One permanent magnet 25 is provided on each of the longitudinal ends of the movable contact 32. This allows the arc A to be extended on both the primary and secondary sides, improving the interruption performance. The permanent magnets 25 are arranged with opposite polarities facing each other. This allows the arc A to be extended in alternate directions on the primary and secondary sides when viewed from the depth direction, as shown in Figures 6 and 10. This prevents the high-speed gas flow generated by the arc A from being biased to one side or the other in the width direction.

[0035] Fixed contactor 31 is columnar and extends in the displacement direction of movable contactor 32. Arc runner 26 has a circular hole 28 formed therein that penetrates in the displacement direction of movable contactor 32, and fixed contactor 31 is fitted into circular hole 28. This allows for easy electrical connection between fixed contactor 31 and arc runner 26. The arc runner 26 is brazed to the fixed contact 31. This ensures reliable electrical connection between the fixed contact 31 and the arc runner 26. The electromagnetic contactor 11 includes an electromagnet section 22. The electromagnet section 22 is disposed inside the sealed container 12, and switches the contact section 21 between open and closed by displacing the movable contactor 32 via the contact support 41. By disposing the electromagnet section 22 inside the sealed container 12 in this way, the electromagnetic contactor 11 becomes easy to handle.

[0036] Next, a comparative example will be described. The comparative example has the same configuration as the above-described electromagnetic contactor 11, except that it does not include the arc runner 26. Therefore, the same components are denoted by the same reference numerals, and detailed descriptions thereof will be omitted. FIG. 11 is a diagram showing a comparative example. 9, a cross section of electromagnetic contactor 71 serving as a comparative example taken along the width and depth directions is shown as viewed from one side in the vertical direction, with contact portion 21 being partially enlarged. In arc extinguishing chamber 23, arc A generated at secondary-side contact portion 21 by interruption is indicated by a thick dotted arrow, and Ac1 to Ac3 indicate changes over time.

[0037] Ac1 is the initial arc, and its starting point is at the center of the width direction of the movable contact 32 and its ending point is at the center of the width direction of the fixed contact 31, so that the arc Ac1 extends towards the front in the depth direction. Since an external magnetic field φ directed in one longitudinal direction is applied to the arc Ac1, a Lorentz force Fc1 directed in one width direction acts on it in accordance with Fleming's left-hand rule. Ac2 is an intermediate arc stretched by the Lorentz force Fc1, with its starting point moving to one side in the width direction of the movable contact 32 and its ending point moving to the cylindrical surface of the fixed contact 31. Arc Ac2 is curved so as to be convex toward one side in the width direction, and extends toward one side in the width direction and the front side in the depth direction, and then toward the other side in the width direction and the front side in the depth direction.

[0038] Ac3 is a later arc that is further stretched by the Lorentz force Fc1, with its starting point moving to the side surface of the movable contact 32 and its ending point remaining at the side surface of the fixed contact 31. Arc Ac3 is curved greatly so as to be convex toward one side in the width direction, and extends toward one side in the width direction and the front side in the depth direction, and then toward the other side in the width direction and the front side in the depth direction. In this way, when arc Ac1 is generated at contact portion 21 by breaking, Lorentz force Fc1 acts in a direction perpendicular to the external magnetic field φ, causing arc Ac1 to be stretched in one direction in the width direction, like arc Ac2 and arc Ac3. However, since arc Ac1 is only stretched in the width direction and not in the depth direction, the arc extinguishing space cannot be fully utilized, and there is room for improvement in terms of improving breaking performance.

[0039] <<Variation>> In the first embodiment, the fixed contactor 31 and the arc runner 26 are fitted together and brazed, but the present invention is not limited to this. For example, the fixed contactor 31 may be press-fitted into the circular hole 28, the female thread of the circular hole 28 may be fitted into the male thread of the fixed contactor 31, or the arc runner 26 may be fixed with a retaining ring. In the first embodiment, the fixed contact 31 is formed in a substantially cylindrical shape extending in the depth direction, but the present invention is not limited to this. For example, the fixed contact 31 may be formed in a plate shape extending in the vertical direction, or in a substantially C-shape or U-shape opening inward in the vertical direction when viewed in the width direction.

[0040] In the first embodiment, a configuration in which a pair of permanent magnets 25 face each other in the vertical direction has been described, but the present invention is not limited to this. That is, a pair of permanent magnets 25 may face each other in the width direction. In this case, an arc runner 26 extending in the vertical direction may be provided so as to be perpendicular to the external magnetic field φ of the permanent magnets 25. In the first embodiment, the arc runner 26 extends in both one and the other width directions, but this is not limiting. That is, when the current flow direction is limited to one direction, the direction in which the arc A extends is limited to either one or the other width direction, and the arc runner 26 may be extended accordingly. In the first embodiment, the gas barrier coating is applied only to the outer peripheral surface of the sealed container 12, but this is not limitative, and the gas barrier coating may also be applied to the inner peripheral surface of the sealed container 12.

[0041] Second Embodiment "composition" The second embodiment shows another aspect of the polarity arrangement of the permanent magnets 25. That is, the second embodiment has the same configuration as the first embodiment, except that a pair of permanent magnets 25 are arranged so that the polarities of the permanent magnets 25 are the same but opposite each other. Therefore, the same reference numerals are used for the common configuration, and detailed description thereof will be omitted. FIG. 12 is a cross-sectional view (cross section DD) of the electromagnetic contactor according to the second embodiment. Here, the DD cross section of the electromagnetic contactor 11 shown in Fig. 3 taken along the vertical and width directions is shown as viewed from the far side in the depth direction. The two permanent magnets 25 have their north poles facing inward in the vertical direction so that they are the same poles facing each other. In this case, an external magnetic field φ is generated that flows from the inside in the vertical direction to the outside in the width direction, as indicated by the dashed arrow.

[0042] Here, the other fixed contact 31 in the vertical direction is the primary side, and one fixed contact 31 in the vertical direction is the secondary side. Therefore, at the other contact portion 21 in the vertical direction, the current of arc A generated during breaking flows from the fixed contact 31 toward the movable contact 32, i.e., toward the back side in the depth direction. A Lorentz force F toward the other side in the width direction acts on the other arc A in the vertical direction due to the external magnetic field φ, as shown by the block arrow. At one contact portion 21 in the vertical direction, the current of arc A generated during breaking flows from the movable contact 32 toward the fixed contact 31, i.e., toward the front side in the depth direction. A Lorentz force F toward the other side in the width direction acts on the one arc A in the vertical direction due to the external magnetic field φ, as shown by the block arrow.

[0043] <<Action and Effect>> Next, the main effects of the second embodiment will be described. The permanent magnets 25 are arranged so that the polarities of the permanent magnets 25 are the same and face each other. Therefore, the external magnetic field φ is different from that of the first embodiment. FIG. 13 is a partially enlarged cross-sectional view (cross-section CC) of the electromagnetic contactor according to the second embodiment. 2 is shown, viewed from one side in the vertical direction, with a CC cross section along the width and depth directions, and a partially enlarged view of the contact portion 21. In the arc extinguishing chamber 23, an arc A generated at the secondary side contact portion 21 by interruption is indicated by a thick dotted arrow, and A1 to A3 indicate changes over time. A1 is the initial arc, and its starting point is at the center of the width direction of the movable contact 32 and its ending point is at the center of the width direction of the fixed contact 31, so that the arc A1 extends toward the front in the depth direction. Since an external magnetic field φ directed in one longitudinal direction is applied to the arc A1, a Lorentz force F1 acts in the other width direction according to Fleming's left-hand rule.

[0044] A2 is an intermediate arc stretched by Lorentz force F1, with its starting point moving to the other side of the width direction on the movable contact 32 and its end point moving from the fixed contact 31 to the arc runner 26. Therefore, arc A2 extends toward the front side in the depth direction and toward the other side in the width direction. Since an external magnetic field φ directed in one longitudinal direction is applied to arc A2, a Lorentz force F2 acts on arc A2 toward the other side in the width direction and toward the back side in the depth direction according to Fleming's left-hand rule. A3 is a later arc that is further stretched by Lorentz force F2, with its starting point moving to the side of the movable contact 32 and its ending point moving to the other side in the width direction of the arc runner 26. Arc A3 is curved greatly so as to be convex toward the other side in the width direction and the far side in the depth direction, and extends toward the other side in the width direction and the far side in the depth direction, then toward one side in the width direction and the near side in the depth direction.

[0045] When an arc A1 is generated at the contact portion 21, a Lorentz force F1 acts in a direction perpendicular to the external magnetic field φ, causing the fixed contact 31 side of the arc A to move along the arc runner 26. Because the arc A2 is tilted relative to the displacement direction of the movable contact 32, the Lorentz force F2 is also tilted relative to the displacement direction of the movable contact 32. As a result, the arc A3 is stretched not only in a direction perpendicular to the displacement direction of the movable contact 32 but also in the displacement direction of the movable contact 32. This effectively utilizes the width and depth of the arc-extinguishing space. Increasing the arc voltage in this way extinguishes the arc A and restores insulation at the contact portion 21. While the secondary-side contact portion 21 has been described above, the same applies to the primary-side contact portion 21. By sufficiently stretching the arc A generated at the contact portion 21 in this way, the arc-breaking performance can be improved while preventing the arc-extinguishing chamber 23 from becoming too large.

[0046] The permanent magnets 25 are arranged so that their polarities are opposite to each other. This makes it possible to suppress biased magnetic interference with the electromagnet section 22. That is, as shown in FIG. 3, the permanent magnets 25 are located close to the front side of the electromagnet section 22 in the depth direction. Therefore, if the permanent magnets 25 are arranged so that their polarities are opposite to each other, an external magnetic field φ is generated in one direction in the vertical direction, which may cause biased magnetic interference and affect the operation of the movable plunger 53. In contrast, if the permanent magnets 25 are arranged so that their polarities are opposite to each other, the external magnetic field φ becomes symmetrical between one side and the other in the vertical direction, as shown in FIG. 12. Therefore, biased magnetic interference with the electromagnet section 22 can be suppressed. Other functions and effects are the same as those of the first embodiment described above.

[0047] Third Embodiment "composition" The third embodiment shows another aspect of fixing the arc runner 26. That is, the third embodiment has the same configuration as the first embodiment described above, except that the arc runner 26 is fixed to the capsule case 13 using an adhesive. Therefore, the same reference numerals are used for the common configuration, and detailed description thereof will be omitted. FIG. 14 is a cross-sectional view (cross-section CC) of the electromagnetic contactor according to the third embodiment. 2 is shown, viewed from one side in the vertical direction, in a CC cross section along the width and depth directions. Only the fixed contactor 31 is insert-molded into the ceiling of the capsule case 13, and a recess 81 into which the arc runner 26 is fitted is formed around the fixed contactor 31. The arc runner 26 is fixed in the recess 81 with adhesive 82, and is positioned in the depth direction by abutting against a step formed on the cylindrical surface of the fixed contactor 31.

[0048] FIG. 15 is an isometric cross-sectional view of the capsule case. Here, cross sections along the vertical and width directions of capsule case 13 before arc runner 26 is fixed are shown, as viewed from the far side in the depth direction, one side in the vertical direction, and the other side in the width direction. Recesses 81 into which arc runners 26 are fitted are formed around each fixed contact 31 on the ceiling surface of capsule case 13. Each recess 81 is formed by ribs surrounding both sides in the vertical direction and both sides in the width direction, and its depth in the depth direction is approximately the thickness of arc runner 26. Arc runner 26 is fitted into recess 81, and circular hole 28 is fitted into fixed contact 31.

[0049] FIG. 16 is an isometric cross-sectional view of a capsule case with an arc runner fixed thereto. Here, cross sections along the vertical and width directions of capsule case 13 after arc runner 26 has been fixed are shown, as viewed from the far side in the depth direction, one side in the vertical direction, and the other side in the width direction. Arc runner 26 is fixed to recess 81 with adhesive 82. The adhesive 82 applied to recess 81 and solidified spreads over the entire back surface and side surfaces of arc runner 26, as shown in FIG. 14. The surface of arc runner 26 is the surface along which arc A moves, and therefore its entire surface is exposed to arc extinguishing chamber 23 so as not to be covered by adhesive 82. Adhesive 82 is first applied to recess 81, and then arc runner 26 is fitted into it.

[0050] <<Action and Effect>> Next, the main effects of the third embodiment will be described. The fixed contact 31 is insert-molded into the sealed container 12, and the arc runner 26 is fixed to the sealed container 12 with an adhesive 82. This allows the arc runner 26 to be fixed with an easier process than insert molding. The sealed container 12 has a recess 81 formed on its inner circumferential surface into which the arc runner 26 fits. This makes it easier to apply the adhesive 82 and also prevents the adhesive 82 from spilling out. Furthermore, since the bonding area can be increased compared to when the arc runner 26 is bonded to a single plane, the arc runner 26 can be firmly fixed. Other functions and effects are the same as those of the first embodiment described above.

[0051] Although the present invention has been described above with reference to a limited number of embodiments, the scope of the invention is not limited thereto, and modifications of the embodiments based on the above disclosure will be obvious to those skilled in the art. [Explanation of symbols]

[0052] 11...electromagnetic contactor, 12...sealed container, 13...capsule case, 14...capsule cover, 15...pipe, 16...insulating barrier, 17...storage section, 21...contact section, 22...electromagnet section, 23...arc extinguishing chamber, 25...permanent magnet, 26...arc runner, 27...adhesive, 28...round hole, 31...fixed contact, 32...moving contact, 33...screw hole, 35...fixed contact, 36...moving contact, 41...contact support, 42...base, 43...holding member, 44...contact spring, 51...spool, 52...sliding cover lar, 53...movable plunger, 54...armature, 55...yoke, 56...plunger ring, 57...back spring, 58...permanent magnet, 59...auxiliary yoke, 61...winding shaft, 62...coil, 71...electromagnetic contactor, 81...recess, 82...adhesive, A...arc, A1...arc, A2...arc, A3...arc, Ac1...arc, Ac2...arc, Ac3...arc, F...Lorentz force, F1...Lorentz force, F2...Lorentz force, Fc1...Lorentz force, φ...external magnetic field

Claims

1. a pair of fixed contacts on which fixed contacts are formed; a movable contactor having a pair of movable contacts, the movable contacts being displaced in a predetermined direction to bring the movable contacts into contact with and separate from the fixed contacts; a permanent magnet that applies an external magnetic field to a contact portion formed by the fixed contact and the movable contact in a direction perpendicular to the displacement direction of the movable contact; an arc runner, which is a conductor electrically connected to the fixed contact in a chamber in which the contact portion is disposed and extends in a direction perpendicular to the external magnetic field as viewed from the displacement direction of the movable contact; a sealed container made of resin in which the contact portion is disposed and in which a breaking gas is sealed, The electromagnetic contactor is characterized in that the fixed contact and the arc runner are insert-molded into the sealed container.

2. An electromagnetic contactor as described in claim 1, characterized in that the arc runner is fixed to the sealed container by adhesive.

3. 3. The electromagnetic contactor according to claim 2, wherein the sealed container has an inner peripheral surface formed with a recess into which the arc runner is fitted.

4. The sealed container is 4. The electromagnetic contactor according to claim 1, further comprising a housing portion that is separated from a chamber in which the contact portion is disposed and that houses the permanent magnet.

5. 5. The electromagnetic contactor according to claim 4, wherein the permanent magnet is fixed to the housing portion with an adhesive.

6. The movable contactor extends in a direction perpendicular to a displacement direction of the movable contactor, the permanent magnet applies the external magnetic field along the longitudinal direction of the movable contact; 6. The electromagnetic contactor according to claim 1, wherein the arc runner extends in a short direction of the movable contactor.

7. 7. The electromagnetic contactor according to claim 6, wherein the arc runner extends toward both one and the other of the short sides of the movable contactor.

8. 8. The electromagnetic contactor according to claim 6, wherein the permanent magnets are provided on both sides of the movable contact in the longitudinal direction.

9. 9. The electromagnetic contactor according to claim 8, wherein the permanent magnets are arranged so that opposite polarities face each other.

10. 9. The electromagnetic contactor according to claim 8, wherein the permanent magnets are arranged so that their polarities are the same and opposite to each other.

11. the fixed contact has a columnar shape extending in the displacement direction of the movable contact, The electromagnetic contactor according to any one of claims 1 to 10, characterized in that the arc runner has a through hole formed therein that penetrates in the displacement direction of the movable contactor, and the fixed contactor is fitted into the through hole.

12. The electromagnetic contactor according to claim 11, wherein the arc runner is brazed to the stationary contact.

13. The electromagnetic contactor according to any one of claims 1 to 5, further comprising an electromagnet portion disposed inside the sealed container and configured to switch the contact portion on and off by displacing the movable contactor via a contact support.

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