Electromagnetic relay
The electromagnetic relay addresses the issue of arc re-ignition by using a tapered portion to guide the arc into an extended space for quick blocking, effectively preventing re-ignition and improving relay reliability.
Patent Information
- Application Number
- JP2021101220
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2021-06-17
- Publication Date
- 2025-04-22
- Estimated Expiration
- 2041-06-17
AI Technical Summary
In electromagnetic relays, the re-ignition of arcs at contacts is a challenge due to the design of the gas passage, which allows high-temperature gases to return to the contact area, potentially reigniting the arc as load capacity increases.
The electromagnetic relay incorporates a tapered portion at the end of the first fixed terminal, which guides the arc away from the contact area and into an extended arc space, effectively blocking the arc and preventing re-ignition.
This design significantly extends the arc into a dedicated arc extension space, allowing it to be quickly blocked and preventing re-ignition, thus enhancing the reliability of the electromagnetic relay.
Smart Images

Figure 0007666155000001 
Figure 0007666155000002 
Figure 0007666155000003
Abstract
Description
[Technical field]
[0001] The present invention relates to an electromagnetic relay. [Background technology]
[0002] In an electromagnetic relay, an arc occurs at the contacts when a current is interrupted. If the temperature of the contacts rises due to this arc, the contacts may melt and generate high-temperature gas including metal vapor. If this high-temperature gas accumulates near the contacts, the insulation performance between the contacts may decrease and the arc may re-ignite. In order to prevent this re-ignition of the arc, the electromagnetic relay disclosed in Patent Document 1 is provided in the case with an arc-extinguishing space that extinguishes the arc, a gas inflow space separate from the arc-extinguishing space, and a gas passage that releases high-temperature gas from the arc-extinguishing space to the gas inflow space. [Prior art documents] [Patent documents]
[0003] [Patent Document 1] JP 2016-24864 A Summary of the Invention [Problem to be solved by the invention]
[0004] In the electromagnetic relay of Patent Document 1, the inlet and outlet of the gas passage are located near the contacts. Therefore, high-temperature gas easily passes through the gas passage and returns to the contacts. When the load capacity increases, the amount of high-temperature gas returning to the vicinity of the contacts also increases, which may cause the arc to re-ignite.
[0005] An object of the present invention is to suppress restrike of an arc occurring at a contact in an electromagnetic relay. [Means for solving the problem]
[0006] An electromagnetic relay according to an embodiment of the present invention includes a first fixed terminal, a second fixed terminal, a movable contact piece, a case, a drive device, and a first magnet. The first fixed terminal includes a first fixed contact. The second fixed terminal includes a second fixed contact and is disposed away from the first fixed terminal. The movable contact piece includes a first movable contact facing the first fixed contact and a second movable contact facing the second fixed contact. The case includes an accommodation space in which the first fixed contact, the second fixed contact, and the movable contact piece are accommodated, and a side wall that covers the accommodation space from a first direction. The drive device moves the movable contact piece in a movement direction including a direction in which the first movable contact approaches the first fixed contact and a direction in which the first movable contact moves away from the first fixed contact. The first magnet is disposed to the side of the first fixed contact and extends an arc generated between the first fixed contact and the first movable contact in a second direction opposite to the first direction. The first fixed terminal includes a first end portion in the second direction. The first end of the first fixed terminal includes a tapered portion that is inclined in a second direction from the first fixed contact toward the first magnet and at least a portion of the tapered portion overlaps with the first magnet when viewed from the direction of movement of the movable contact piece. The case includes an arc extension space that expands in the second direction from the tapered portion and communicates with the accommodation space.
[0007] In this electromagnetic relay, the arc generated between the first fixed contact and the first movable contact is extended in the second direction. That is, the bright spot of the arc moving through the first fixed terminal moves to the first end. As a result, the bright spot of the arc that has moved to the first end is guided by the tapered portion provided at the first end, and is easily moved to the rear side of the first magnet, and moves in the first direction. This allows the arc to be significantly extended in the arc extension space expanded in the first direction from the tapered portion, so that the arc can be quickly interrupted. As a result, re-ignition of the arc generated between the first fixed contact and the first movable contact can be suppressed.
[0008] The first fixed terminal may include a first external connection portion protruding from the side wall in a first direction. The second fixed terminal may include a second external connection portion protruding from the side wall in the first direction. In this case, in an electromagnetic relay in which an arc generated between the first fixed contact and the first movable contact is extended in a direction away from the first external connection portion, restrike of the arc generated between the first fixed contact and the first movable contact can be suppressed.
[0009] The first magnet may include a magnet end in the second direction. The magnet end of the first magnet may be disposed in the second direction relative to the first fixed contact. In this case, the arc is easily drawn into the magnet end of the first magnet, so that the arc can be quickly interrupted in the arc extension space.
[0010] The first magnet may include a first surface in a third direction from the first fixed contact toward the second fixed contact, and a second surface opposite to the first surface. The tapered portion may protrude from the first surface of the first magnet in the third direction when viewed from the direction of movement of the movable contact piece. In this case, the bright point of the arc that has moved to the first end portion is more likely to move to the back side of the first magnet.
[0011] The first magnet may include a first surface in a third direction from the first fixed contact toward the second fixed contact, and a second surface opposite to the first surface. The first end of the first fixed terminal may include a corner portion that is disposed near the second surface of the first magnet when viewed from the moving direction of the movable contact piece and is connected to the tapered portion. In this case, the movement of the bright spot of the arc moving through the first fixed terminal can be stopped at the corner portion. This makes it possible to prevent the arc from moving too far away from the movable contact piece. As a result, it is possible to prevent the phenomenon of the arc being interrupted and then re-ignited.
[0012] The first end of the first fixed terminal may include a first flat portion and a second flat portion spaced apart from the first flat portion. The tapered portion may be disposed between the first flat portion and the second flat portion. In this case, for example, when the first fixed terminal is press-fitted into the case from the second direction, the first fixed terminal can be easily press-fitted into the case.
[0013] The drive device may include a spool and a fixed core disposed inside the spool and in a second direction relative to the first fixed terminal. The spool may include a flange for ensuring an insulation distance between the first fixed terminal and the fixed core. The flange of the spool may be disposed in a third direction from the first fixed contact toward the second fixed contact relative to the first magnet. In this case, the arc can be prevented from hitting the flange, improving durability of the flange. In addition, the arc extension is less likely to be hindered by the flange, so the arc can be quickly interrupted in the arc extension space.
[0014] The electromagnetic relay may further include a second magnet disposed to the side of the first fixed contact facing the first magnet and extending the arc generated between the second fixed contact and the second movable contact. The flange of the spool may be disposed between the first magnet and the second magnet as viewed from the direction of movement of the movable contact piece. In this case, the arc can be quickly interrupted in the arc extension space while ensuring an insulation distance between the first fixed terminal and the fixed iron core, and between the second fixed terminal and the fixed iron core. Effect of the Invention
[0015] According to the present invention, restrike of an arc occurring at a contact in an electromagnetic relay is suppressed. [Brief description of the drawings]
[0016] [Figure 1] FIG. [Diagram 2] FIG. 2 is a perspective view of the electromagnetic relay with the cover removed. [Diagram 3] A partial cross-sectional view of an electromagnetic relay cut along a plane perpendicular to the vertical direction. [Figure 4] 2 is a partial cross-sectional view of the electromagnetic relay taken along a plane perpendicular to the front-rear direction. FIG. [Diagram 5] FIG. 4 is a view of the first fixed terminal as seen from the front. [Figure 6] 5 is an enlarged view of the periphery of a first fixed terminal in FIG. 4. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0017] An electromagnetic relay 1 according to an embodiment will be described below with reference to the drawings. As shown in Fig. 1 and Fig. 2, the electromagnetic relay 1 includes a case 2, a contact device 3, and a drive device 4.
[0018] In the following description, the direction in which the contact device 3 and the drive device 4 are disposed relative to a base 21 of the case 2, which will be described later, is referred to as the upward direction (an example of the second direction), the opposite direction is referred to as the downward direction (an example of the first direction), the direction in which the contact device 3 is disposed relative to the drive device 4 is referred to as the forward direction, the opposite direction is referred to as the rearward direction, and the left-right direction on the paper surface of Fig. 3 is referred to as the left-right direction. However, these directions are defined for the sake of convenience of description, and do not limit the arrangement direction of the electromagnetic relay 1.
[0019] The case 2 is formed in a box shape. The case 2 is formed of an insulating material such as resin and includes a base 21 and a cover 22. The base 21 supports the contact device 3 and the drive device 4. The base 21 includes a bottom 21a, outer walls 21b to 21e, and an inner wall 21f (see FIG. 3). The bottom 21a extends in a direction perpendicular to the up-down direction. The outer wall 21b extends upward from the front edge of the bottom 21a. The outer wall 21c extends upward from the rear edge of the bottom 21a. The outer wall 21d extends upward from the left edge of the bottom 21a. The outer wall 21e extends upward from the right edge of the bottom 21a. The inner wall 21f extends upward from the bottom 21a. The inner wall 21f extends in the left-right direction between the outer wall 21d and the outer wall 21e. The inner wall 21f is disposed between the contact device 3 and the drive device 4 in the front-rear direction.
[0020] The cover 22 is open downward, and is attached to outer walls 21b to 21e of the base 21 so as to cover the bottom portion 21a of the base 21 from above. The contact device 3 and the drive device 4 are housed in the case 2.
[0021] 3, the contact device 3 includes a first fixed terminal 11, a second fixed terminal 12, and a movable contact piece 13. In the following description, the first fixed terminal 11 and the second fixed terminal 12 may be referred to as fixed terminals 11, 12.
[0022] The fixed terminals 11, 12 are made of a conductive material such as copper. The fixed terminals 11, 12 are plate-shaped terminals and extend in a direction perpendicular to the front-rear direction. The fixed terminals 11, 12 are supported by the bottom 21a of the base 21. The fixed terminals 11, 12 are attached to the base 21 from above. In this embodiment, the fixed terminals 11, 12 are press-fitted and fixed to the bottom 21a of the base 21. The fixed terminals 11, 12 are disposed in front of the inner wall 21f.
[0023] As shown in Figures 3 to 5, the first fixed terminal 11 includes a first fixed contact 11a, a first external connection portion 11b, and a first end portion 11c. The first fixed contact 11a is disposed on the front surface of the first fixed terminal 11. The first fixed contact 11a is fixed to the first fixed terminal 11 by crimping. The first fixed contact 11a may be integral with the first fixed terminal 11. The first external connection portion 11b protrudes downward from the bottom portion 21a of the base 21, and is electrically connected to an external device (not shown).
[0024] The first end 11c is the upper end of the first fixed terminal 11. The first end 11c is exposed within the case 2. In this embodiment, the entire first end 11c is exposed within the case 2. The first end 11c extends in the left-right direction.
[0025] As shown in FIG. 5, the first end 11c includes a first flat portion 11d, a tapered portion 11e, a step portion 11f, a second flat portion 11g, and a corner portion 11h. The first flat portion 11d is located above the first fixed contact 11a. The first flat portion 11d includes a flat surface perpendicular to the up-down direction. The tapered portion 11e is inclined with respect to the first flat portion 11d when viewed from the front-rear direction. The tapered portion 11e extends leftward and downward from the first flat portion 11d. The step portion 11f connects the tapered portion 11e and the second flat portion 11g. The step portion 11f extends downward from the left end of the tapered portion 11e. The step portion 11f includes a flat surface perpendicular to the left-right direction. The second flat portion 11g extends leftward from the lower end of the step portion 11f. The second flat portion 11g includes a flat surface perpendicular to the up-down direction. The corner portion 11h is a corner of the boundary between the tapered portion 11e and the step portion 11f.
[0026] The second fixed terminal 12 is disposed away from the first fixed terminal 11 in the right direction. The second fixed terminal 12 has a shape symmetrical to the first fixed terminal 11. The second fixed terminal 12 includes a second fixed contact 12a, a second external connection portion 12b, and a second end portion 12c. The second fixed contact 12a is disposed on the front surface of the second fixed terminal 12. The second fixed contact 12a is fixed to the second fixed terminal 12 by crimping. The second fixed contact 12a may be integral with the second fixed terminal 12. The second external connection portion 12b protrudes downward from the bottom portion 21a of the base 21 and is electrically connected to an external device (not shown). The second end portion 12c has a shape symmetrical to the first end portion 11c of the first fixed terminal 11, and includes a configuration similar to that of the first end portion 11c of the first fixed terminal 11. A detailed description of the second end portion 12c is omitted.
[0027] The movable contact piece 13 is a plate-shaped terminal and is made of a conductive material such as copper. The movable contact piece 13 is disposed in front of the fixed terminals 11 and 12. The movable contact piece 13 is substantially T-shaped when viewed from the front-rear direction. The movable contact piece 13 includes a first movable contact 13a, a second movable contact 13b, a vertical extension portion 13c, and a horizontal extension portion 13d.
[0028] The first movable contact 13a and the second movable contact 13b are fixed to the movable contact piece 13 by crimping. The first movable contact 13a and the second movable contact 13b are arranged on the rear surface of the left-right extension portion 13d. The first movable contact 13a faces the first fixed contact 11a in the front-rear direction. The first movable contact 13a can contact the first fixed contact 11a. The second movable contact 13b is arranged away from the first movable contact 13a in the right direction. The second movable contact 13b faces the second fixed contact 12a in the front-rear direction. The second movable contact 13b can contact the second fixed contact 12a. The first movable contact 13a and the second movable contact 13b may be integral with the movable contact piece 13.
[0029] The vertical extension portion 13c extends in the vertical direction, and an upper portion of the vertical extension portion 13c is connected to the drive device 4. The horizontal extension portion 13d extends in the horizontal direction from a lower portion of the vertical extension portion 13c.
[0030] The drive device 4 is disposed above the contact device 3. The drive device 4 moves the movable contact piece 13 in a direction in which the first movable contact 13a approaches the first fixed contact 11a and in a direction in which the first movable contact 13a moves away from the first fixed contact 11a. The drive device 4 also moves the movable contact piece 13 in a direction in which the second movable contact 13b approaches the second fixed contact 12a and in a direction in which the second movable contact 13b moves away from the second fixed contact 12a. In this embodiment, the drive device 4 moves the movable contact piece 13 in the front-rear direction (an example of a movement direction).
[0031] As shown in FIGS. 2 and 4, the drive device 4 includes a spool 41, a coil 42, a yoke 43, a movable iron piece 44, a resin member 45, a return spring 46, and a fixed iron core 47.
[0032] The spool 41 is disposed above the fixed terminals 11 and 12. The spool 41 includes flanges 41a and 41b, a body 41c, and a flange 41d. The outer diameters of the flanges 41a and 41b are larger than the outer diameter of the body 41c. The flange 41a is connected to the front end of the body 41c. The flange 41b is connected to the rear end of the body 41c. The body 41c is cylindrical, and the coil 42 is wound around the outer periphery. The flange 41d is provided to ensure an insulation distance between the fixed terminals 11 and 12 and the fixed iron core 47. As shown in FIG. 3 and FIG. 4, the flange 41d extends forward from the front surface of the flange 41a. The flange 41d is disposed above the fixed terminals 11 and 12. The flange 41d extends in a direction perpendicular to the up-down direction.
[0033] The coil 42 is wound around the outer periphery of the spool 41. The yoke 43 has an L-shaped bent shape. The yoke 43 includes a connecting portion 43a and an extending portion 43b. The connecting portion 43a is disposed behind the spool 41 and is connected to the fixed core 47. The extending portion 43b extends forward from the upper end of the connecting portion 43a so as to cover the upper side of the coil 42.
[0034] The movable iron piece 44 is disposed in front of the fixed iron core 47. The movable iron piece 44 is rotatably supported by the yoke 43 at the front end of the extension portion 43b. The resin member 45 insulates the movable iron piece 44 from the movable contact piece 13. The resin member 45 connects the movable iron piece 44 to the movable contact piece 13. In detail, the movable iron piece 44 and the movable contact piece 13 are insert molded into the resin member 45. As a result, the resin member 45 and the movable contact piece 13 rotate integrally with the movable iron piece 44 in response to the rotation of the movable iron piece 44.
[0035] The return spring 46 is a coil spring and extends in the front-rear direction. The front end of the return spring 46 is connected to the movable iron piece 44, and the rear end is connected to the yoke 43. The return spring 46 biases the movable contact piece 13 forward via the movable iron piece 44 and the resin member 45. That is, the return spring 46 biases the movable contact piece 13 in a direction in which the first movable contact 13a moves away from the first fixed contact 11a, and in a direction in which the second movable contact 13b moves away from the second fixed contact 12a. The fixed iron core 47 is disposed in the body portion 41c of the spool 41, and penetrates the flange portions 41a and 41b of the spool 41 in the front-rear direction.
[0036] Next, the operation of the electromagnetic relay 1 will be described. When no voltage is applied to the coil 42, as shown in FIG. 3, the first movable contact 13a is separated from the first fixed contact 11a by the elastic force of the return spring 46, and the second movable contact 13b is separated from the second fixed contact 12a. When a voltage is applied to the coil 42 and the coil 42 is excited, the movable iron piece 44 is attracted to the fixed iron core 47 by the electromagnetic force, and the movable iron piece 44 rotates against the elastic force of the return spring 46. As a result, the movable contact piece 13 moves backward, and the first movable contact 13a contacts the first fixed contact 11a, and the second movable contact 13b contacts the second fixed contact 12a. When the application of the voltage to the coil 42 is stopped, the movable iron piece 44 rotates by the elastic force of the return spring 46. As a result, the movable contact piece 13 moves forward, the first movable contact 13a separates from the first fixed contact 11a, and the second movable contact 13b separates from the second fixed contact 12a.
[0037] Here, the case 2 further includes a side wall 23, an accommodation space 24, magnet accommodation portions 25, 26, gas inflow spaces 27, 28, and arc extension spaces 29, 30, as shown in FIGS.
[0038] In this embodiment, the side wall 23 is formed by the bottom 21a of the base 21. The side wall 23 covers the storage space 24 and the gas inflow spaces 27, 28 from below. The side wall 23 includes through holes 23a, 23b. The through holes 23a, 23b are holes that penetrate the side wall 23 in the up-down direction. The through hole 23a is formed below the magnet storage portion 25. The through hole 23b is formed below the magnet storage portion 26.
[0039] The accommodation space 24 is provided between the base 21 and the cover 22. The accommodation space 24 is provided in the left-right direction between the magnet accommodation portion 25 and the magnet accommodation portion 26. The first fixed contact 11a, the second fixed contact 12a, and the movable contact piece 13 are accommodated in the accommodation space 24.
[0040] The magnet storage portion 25 is integrally formed with the base 21. The magnet storage portion 25 extends rearward and vertically from the outer wall 21b of the base 21. The magnet storage portion 25 is disposed away from the bottom 21a of the base 21 in the upward direction. The magnet storage portion 25 is disposed on the left side of the first fixed contact 11a and the first movable contact 13a. The magnet storage portion 25 is disposed between the storage space 24 and the gas inflow space 27. The magnet storage portion 25 divides the storage space 24 and the gas inflow space 27 in the left-right direction. The magnet storage portion 25 extends upward from the first fixed contact 11a and the first movable contact 13a with respect to the bottom 21a of the base 21. The magnet storage portion 25 extends upward from the first fixed terminal 11 with respect to the bottom 21a of the base 21.
[0041] The magnet accommodating portion 25 includes an insertion opening 25a. The insertion opening 25a is formed at the lower end of the magnet accommodating portion 25 and opens downward. The insertion opening 25a is disposed above the bottom portion 21a of the base 21. The insertion opening 25a overlaps with the through hole 23a in the up-down direction.
[0042] The magnet accommodating portion 26 has a symmetrical shape to the magnet accommodating portion 25, and will be described briefly. The magnet accommodating portion 26 is disposed to the right of the second fixed contact 12a and the second movable contact 13b. The magnet accommodating portion 26 is disposed between the accommodating space 24 and the gas inflow space 27. The magnet accommodating portion 26 divides the accommodating space 24 and the gas inflow space 27 in the left-right direction. The magnet accommodating portion 25 includes an insertion opening 26a.
[0043] The gas inflow spaces 27, 28 are provided between the base 21 and the cover 22. The gas inflow spaces 27, 28 are different from the storage space 24. The gas inflow space 27 is disposed to the left of the storage space 24. The gas inflow space 27 is provided between the magnet storage portion 25 and the outer wall 21d of the base 21 in the left-right direction. The gas inflow space 28 is disposed to the right of the storage space 24. The gas inflow space 28 is provided between the magnet storage portion 26 and the outer wall 21e of the base 21 in the left-right direction.
[0044] The arc extension spaces 29, 30 communicate with the accommodation space 24. The arc extension space 29 extends upward from the tapered portion 11e of the first end portion 11c of the first fixed terminal 11. The arc extension space 30 extends upward from the tapered portion of the second end portion 12c of the second fixed terminal 12.
[0045] The electromagnetic relay 1 includes support members 50 and 51, gas flow paths 60 and 61, a first magnet 70, and a second magnet 71.
[0046] The support member 50 is separate from the base 21. The support member 50 is fixed to the bottom 21a of the base 21 by, for example, press fitting. The support member 50 closes the insertion opening 25a of the magnet accommodating portion 25 and the through-hole 23a of the side wall 23. The support member 50 supports the first magnet 70 from below. The support member 50 includes a through-hole 50a that penetrates in the left-right direction.
[0047] The support member 51 closes the insertion opening 26a of the magnet accommodating portion 26 and the through hole 23b of the side wall 23. The support member 51 includes a through hole 51a. The support member 51 has a similar configuration to the support member 50, and therefore a detailed description thereof will be omitted.
[0048] The gas flow path 60 is provided between the side wall 23 of the case 2 and the first magnet 70. The gas flow path 60 extends in the left-right direction and connects the accommodation space 24 and the gas inflow space 27. The gas flow path 60 is provided below the first magnet 70. The gas flow path 60 is composed of a through hole 60a that passes between the magnet accommodation portion 25 and the side wall 23 in the left-right direction and a through hole 50a in the support member 50. The through hole 60a is formed so as to be connected to the through hole 50a in the support member 50 in the left-right direction.
[0049] The gas flow path 61 is provided between the side wall 23 of the case 2 and the second magnet 71. The gas flow path 61 extends in the left-right direction and connects the accommodation space 24 and the gas inflow space 28. The gas flow path 61 is provided below the second magnet 71. The gas flow path 61 is composed of a through hole 61a that passes between the magnet accommodation portion 26 and the side wall 23 in the left-right direction, and a through hole 51a of the support member 51. The through hole 61a is arranged so as to be connected to the through hole 51a of the support member 51 in the left-right direction.
[0050] The first magnet 70 is, for example, a rectangular permanent magnet. The first magnet 70 is disposed to the left of the first fixed contact 11a and the first movable contact 13a. The first magnet 70 is accommodated in the magnet accommodating portion 25. The first magnet 70 is inserted into the magnet accommodating portion 25 from below. In this embodiment, the first magnet 70 is composed of a magnet body and a yoke disposed to the left of the magnet body.
[0051] As shown in Fig. 6, the first magnet 70 overlaps with the first fixed terminal 11 in the front-rear direction. The first magnet 70 includes a magnet end portion 70a. The magnet end portion 70a is the upper end of the first magnet 70. The magnet end portion 70a is disposed above the first fixed contact 11a. The magnet end portion 70a is disposed above the first end portion 11c of the first fixed terminal 11.
[0052] The first magnet 70 includes a first surface 70b and a second surface 70c opposite to the first surface 70b. The first surface 70b is the surface of the first magnet 70 in the direction from the first fixed contact 11a to the second fixed contact 12a.
[0053] The first magnet 70 is disposed so that magnetic flux flows to the left near the first fixed contact 11a. The first magnet 70 extends the arc A1 generated between the first fixed contact 11a and the first movable contact 13a in an upward direction. In detail, for example, when a current flows from the first movable contact 13a to the first fixed contact 11a, an upward Lorentz force acts on the arc A1, causing the arc A1 to extend in an upward direction. As the arc A1 extends upward, it is extended so as to be drawn into the magnet end 70a, as shown in FIG. 4.
[0054] The second magnet 71 is disposed to the right of the second fixed contact 12a and the second movable contact 13b. The second magnet 71 is housed in the magnet housing portion 26. The second magnet 71 overlaps with the second fixed terminal 12 in the front-rear direction.
[0055] The second magnet 71 is disposed so that magnetic flux flows to the left near the second fixed contact 12a. The second magnet 71 is disposed so that the opposite poles of the second magnet 71 and the first magnet 70 face each other. The second magnet 71 extends the arc A2 generated between the second fixed contact 12a and the second movable contact 13b downward. In detail, for example, when a current flows from the second fixed contact 12a to the second movable contact 13b, a downward Lorentz force acts on the arc A2, causing the arc A2 to extend downward. As the arc A2 extends downward, it is extended so as to be drawn into the lower end of the second magnet 71, as shown in FIG. 4.
[0056] As shown in Fig. 6, the tapered portion 11e of the first end 11c of the first fixed terminal 11 is inclined downward from the first fixed contact 11a toward the first magnet 70. At least a portion of the tapered portion 11e overlaps with the first magnet 70 in the front-rear direction. The tapered portion 11e extends to the right (an example of a third direction) with respect to the first surface 70b of the first magnet 70 when viewed from the front-rear direction. The tapered portion 11e extends to the right with respect to the magnet accommodating portion 25 when viewed from the front-rear direction. The corner portion 11h of the first end 11c of the fixed terminal 11 is disposed in the vicinity of the second surface 70c of the first magnet 70 when viewed from the front-rear direction.
[0057] As shown in FIG. 3, at least a part of the tapered portion 11e does not overlap with the flange portion 41d of the spool 41 when viewed from the top-bottom direction. In this embodiment, most of the tapered portion 11e is exposed from the flange portion 41d of the spool 41 when viewed from the top-bottom direction. The corner portion 11h of the first end portion 11c of the fixed terminal 11 is disposed near the second surface 70c of the first magnet 70 when viewed from the front-rear direction. The corner portion 11h is disposed at a position closer to the second surface 70c than the first surface 70b of the first magnet 70 when viewed from the front-rear direction. The corner portion 11h is disposed at a position overlapping with either the first magnet 70 or the magnet accommodating portion 25 in the front-rear direction.
[0058] As shown in Figs. 4 and 6, the flange 41d of the spool 41 is disposed to the right of the first magnet 70. The flange 41d overlaps with the first flat portion 11d and the first fixed contact 11a in the up-down direction. The flange 41d is disposed between the first magnet 70 and the second magnet 71 when viewed from the front-rear direction. The flange 41d is disposed only in the range between the first magnet 70 and the second magnet 71 in the left-right direction. The flange 41d is disposed between the magnet housing portion 25 and the magnet housing portion 26 in the left-right direction. The dimension of the flange 41d in the left-right direction is smaller than the dimension between the first magnet 70 and the second magnet 71.
[0059] In the above-described electromagnetic relay 1, the arc A1 generated between the first fixed contact 11a and the first movable contact 13a is extended upward. That is, the bright point of the arc A1 moving through the first fixed terminal 11 moves to the first end 11c. As a result, the bright point of the arc A1 that has moved to the first end 11c is guided by the tapered portion 11e provided at the first end 11c and becomes easier to move to the back side of the first magnet 70, and moves downward. As a result, the arc A1 can be significantly extended in the arc extension space 29 that is extended upward from the tapered portion 11e, and the arc A1 can be quickly interrupted. As a result, the re-ignition of the arc A1 can be suppressed.
[0060] Since the flange 41d of the spool 41 is disposed between the first magnet 70 and the second magnet 71 when viewed from the front-rear direction, the arc A1 is prevented from hitting the flange 41d, compared to when the flange 41d extends to a position where it overlaps with the first magnet 70. This prevents the flange 41d from being affected by the arc, improving durability of the flange 41d. In addition, the arc A1 is less likely to be hindered by the flange 41d, so the arc A1 can be quickly interrupted in the arc extension space 29.
[0061] In this embodiment, since the high-temperature gas due to the arc A2 can be released from the accommodation space 24 to the gas inflow space 28 by the gas flow passage 61, restrike of the arc A2 can also be suppressed.
[0062] Since the first end 11c of the first fixed terminal 11 includes the first flat portion 11d and the second flat portion 11g, the first fixed terminal 11 can be easily press-fitted and fixed from above the base 21. Furthermore, since the first end 11c includes the corner portion 11h, the movement of the bright spot of the arc A1 moving through the first fixed terminal 11 can be stopped at the corner portion 11h. This makes it possible to prevent the arc A1 from moving too far away from the movable contact piece 13. As a result, it is possible to prevent a phenomenon in which the arc A1 is interrupted and then re-ignited.
[0063] Although one embodiment of the present invention has been described above, the present invention is not limited to the above embodiment, and various modifications are possible without departing from the gist of the invention.
[0064] The configurations of the contact device 3 and the driving device 4 may be changed. For example, the configuration of the first fixed terminal 11 may be changed. The first external connection portion 11b may protrude from the outer wall 21e of the base 21. The first end portion 11c may include at least the tapered portion 11e. In the front-rear direction, the entire tapered portion 11e may overlap the first magnet 70. The tapered portion 11e may extend to the outer wall 21d. The position of the corner portion 11h may be changed. The driving device 4 may have a plunger-type structure. [Explanation of symbols]
[0065] 1 Electromagnetic relay 2 Cases 4. Drive unit 11 1st fixed terminal 11a 1st fixed contact 11c 1st end 11e Tapered section 12 2nd fixed terminal 12a 2nd fixed contact 13 Movable contact piece 13a 1st movable contact 13b 2nd movable contact 23 Side wall 24 Containment Space 29 Arc extension space 41d Tsubabe 70 First Magnet 70a Magnet end
Claims
1. a first fixed terminal including a first fixed contact; a second fixed terminal including a second fixed contact and spaced apart from the first fixed terminal; a movable contact piece including a first movable contact facing the first fixed contact and a second movable contact facing the second fixed contact; a case including an accommodation space in which the first fixed contact, the second fixed contact, and the movable contact piece are accommodated, and a side wall covering the accommodation space from a first direction; a drive device that moves the movable contact piece in a moving direction including a direction in which the first movable contact approaches the first fixed contact and a direction in which the first movable contact moves away from the first fixed contact; a first magnet disposed on a side of the first fixed contact and configured to extend an arc generated between the first fixed contact and the first movable contact in a second direction opposite to the first direction; Equipped with the first fixed terminal includes a first end in the second direction, the first end of the first fixed terminal is disposed in a direction in which the first movable contact approaches the first fixed contact with respect to the first magnet, the first end of the first fixed terminal is inclined in the second direction from the first fixed contact toward the first magnet, and includes a tapered portion at least a portion of which overlaps with the first magnet in the moving direction; the case includes an arc extension space that expands in the second direction from the tapered portion and communicates with the accommodation space, the drive device includes a spool and a fixed core disposed inside the spool and in the second direction relative to the first fixed terminal, the spool includes a flange portion for ensuring an insulation distance between the first fixed terminal and the fixed core, The flange portion of the spool is disposed in a third direction from the first fixed contact toward the second fixed contact with respect to the first magnet and overlaps with the first fixed contact when viewed from the second direction. Electromagnetic relay.
2. the first fixed terminal includes a first external connection portion protruding from the side wall in the first direction, the second fixed terminal includes a second external connection portion protruding from the side wall in the first direction; 2. An electromagnetic relay as claimed in claim 1.
3. the first magnet includes a magnet end in the second direction; The magnet end of the first magnet is disposed in the second direction relative to the first fixed contact.
3. An electromagnetic relay according to claim 1 or 2.
4. The first magnet includes a first surface in the third direction and a second surface opposite to the first surface, The tapered portion protrudes in the third direction from the first surface of the first magnet when viewed from the movement direction.
4. An electromagnetic relay according to claim 1.
5. The first magnet includes a first surface in the third direction and a second surface opposite to the first surface, the first end of the first fixed terminal includes a corner portion that is disposed near a second surface of the first magnet when viewed from the moving direction and is connected to the tapered portion; 5. An electromagnetic relay according to claim 1.
6. the first end of the first fixed terminal includes a first flat portion and a second flat portion spaced apart from the first flat portion; The tapered portion is disposed between the first flat portion and the second flat portion.
6. An electromagnetic relay according to claim 1.
7. a second magnet disposed on a side of the first fixed contact so as to face the first magnet and extend an arc generated between the second fixed contact and the second movable contact; The flange portion of the spool is disposed between the first magnet and the second magnet as viewed from the moving direction.
7. An electromagnetic relay according to claim 1.
Citation Information
Patent Citations
Contact mechanism and electromagnetic contactor employing the same
JP2016024864A
Electromagnetic relay
WO2016088485A1