JP2013246873A - Contact device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a contact device capable of more surely extinguishing arc by preventing reignition of arc and increasing arc voltage.SOLUTION: The contact device includes a pair of contact points composed of a pair of fixed terminals 1 respectively having a fixed contact 10, and a movable contactor 2 contacted and separated to/from each fixed contact 10, a sealed container 4 for hermetically sealing each contact part, and a permanent magnet 42 for driving arc generated at each contact part in a direction of leaving each contact part, and the permanent magnet 42 is arranged so as to make a magnetic field B1 applied to arc increase as the arc leaves each contact part.

Description

  The present invention relates to a contact device.

  2. Description of the Related Art Conventionally, an electromagnetic relay that is used as a relay of a traveling circuit of an electric vehicle, a hybrid vehicle, or the like and switches between energization and interruption of current is known, and is disclosed in Patent Document 1, for example. The conventional example described in Patent Document 1 switches between energization and interruption of bidirectional currents having different sizes, and includes a coil that generates magnetic force, a pair of contact portions that are opened and closed by magnetic force, and a contact portion. And an arc extinguishing magnet body for extinguishing the generated arc. The pair of contact portions is a pair of movable contacts fixed to a pair of fixed contacts held in the vicinity of the distal end portions of the pair of fixed holders fixed to the main body and a movable holder that moves forward and backward with respect to the fixed holder. It is comprised by the contact.

  In this conventional example, in any one of the pair of contact portions, the direction in which the arc generated when interrupting the large current out of the bidirectional current is stretched by the arc extinguishing magnet body is the tip direction of the fixed holder. It is comprised so that. As a result, in this conventional example, it is possible to smoothly cut off both bidirectional currents.

JP 2010-267470 A

  By the way, in the electromagnetic relay in which the contact portion is sealed in the container as in the above-described conventional example, since the space for extinguishing the arc is limited, the arc cannot be extinguished when interrupting a large current. There is a possibility that it cannot be shut off. In order to solve this, it is necessary to stretch the arc to increase the arc voltage. In the above conventional example, the arc is stretched by utilizing the Lorentz force generated by the magnetic field generated by the arc extinguishing magnet and the arc current flowing between the contacts.

  Here, in the conventional example, the arc extinguishing magnet body is arranged so that the magnetic field is strongest in the vicinity of the contact portion in the arc extinguishing space for extending the arc. For this reason, if the magnetic field generated by the arc-extinguishing magnet is increased in order to increase the arc voltage and extinguish the arc more reliably, the arc existing in the vicinity of the contact portion will be diffused in a short time. . Then, for example, when the contacts are separated, the arc may extinguish in a state where the contacts are not sufficiently separated from each other, which may cause re-ignition.

  Of course, if the magnetic field generated by the arc-extinguishing magnet is weakened, the arc will not diffuse in a short time, so the arc will not extinguish until the contacts are sufficiently separated from each other, reducing the possibility of reignition. Can do. However, in this case, there is a problem that it is difficult to achieve the object of increasing the arc voltage and extinguishing the arc more reliably.

  The present invention has been made in view of the above points, and an object of the present invention is to provide a contact device that can prevent re-ignition and increase the arc voltage to extinguish the arc more reliably.

  The contact device of the present invention includes a pair of fixed terminals each having a fixed contact, a pair of contact parts each including a movable contact contacting and separating from each of the fixed contacts, and a seal for hermetically sealing each of the contact parts. A permanent magnet for driving an arc generated at each contact portion in a direction away from each contact portion, and the magnetic field applied to the arc increases as the distance from the contact portion increases. It is characterized by arranging.

  In this contact device, it is preferable that a plurality of the permanent magnets are arranged for each of the contact portions.

  In this contact device, it is preferable that the permanent magnet is embedded in the wall of the sealed container.

  The contact device includes a housing that stores at least the sealing container and the permanent magnet, and the permanent magnet is disposed at a position facing the sealing container and farthest from the contact portion in the housing. It is preferable.

  In this contact device, at least one end of the fixed terminal or the movable contact is formed with a curved surface in which the distance between the fixed contact and the movable contact becomes longer as the distance from the contact is increased. It is preferable to do.

  In this contact device, at least one end of the fixed terminal or the movable contact is provided with an inclined surface in which the distance between the fixed contact and the movable contact becomes longer as the distance from the contact is increased. It is preferable to form.

  In the present invention, each permanent magnet is arranged so that the magnetic field applied to the arc increases as the distance from each contact portion increases. For this reason, since the magnetic field by a permanent magnet is weak in the vicinity of the contact portion, the arc generated between the contacts does not diffuse in a short time. Therefore, since the arc is not extinguished until the contacts are sufficiently separated from each other, re-ignition can be prevented. Moreover, since the magnetic field by a permanent magnet is strong in the position away from the contact part, the arc extended to the position away from the contact part can be further extended, and the arc can be extinguished more reliably.

BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows Embodiment 1 of the contact apparatus which concerns on this invention, (a) is principal part sectional drawing, (b) is sectional drawing seen from upper direction, (c) is explanatory drawing about arc extinction of an arc. is there. It is sectional drawing which shows the basic composition of the contact apparatus which concerns on this invention. It is a figure which shows the other structure of Embodiment 1 of the contact apparatus which concerns on this invention, (a) is principal part sectional drawing, (b) is explanatory drawing about arc extinction. It is a figure which shows the other structure in a contact apparatus same as the above, (a) is principal part sectional drawing, (b) is explanatory drawing about arc extinction. It is sectional drawing seen from the upper side which shows Embodiment 2 of the contact apparatus which concerns on this invention. It is principal part sectional drawing which shows Embodiment 3 of the contact apparatus which concerns on this invention, (a) is a figure at the time of forming a curved surface in the edge part of a movable contact, (b) is inclined in the edge part of a movable contact It is a figure at the time of forming a surface.

(Embodiment 1)
Hereinafter, a contact device according to a first embodiment of the present invention will be described with reference to the drawings. In the following description, the top, bottom, left, and right in FIG. 2 are defined as the top, bottom, left, and right directions, the front side of the page is the front direction, and the back side of the page is the back direction. In the present embodiment, as shown in FIG. 2, the contact block A1 and the electromagnet block B1 are integrally combined and housed in a hollow box-shaped housing (not shown). In FIG. 2, the permanent magnet 42 described later is not shown.

  The contact block A <b> 1 includes a pair of fixed terminals 1, a movable contact 2, a holding member 3, and a sealing container 4. Each fixed terminal 1 is formed in a cylindrical shape from a conductive material such as copper. In the present embodiment, the lower end portion of each fixed terminal 1 becomes a fixed contact 10 that contacts and separates from the movable contact 2. Each fixed contact 10 may be provided by fixing a contact material to the lower end of each fixed terminal 1. Each fixed terminal 1 is inserted through a pair of through holes 40A of a case 40 described later. In addition, a flange 11 exposed to the outside of the case 40 is formed at the upper end of each fixed terminal 1. Each flange portion 11 is joined to the case 40 by brazing while protruding from the upper surface of the case 40.

  The movable contact 2 is formed in a rectangular flat plate shape, and is arranged at a position facing each fixed contact 10 at a predetermined interval along the vertical direction. Further, a positioning protrusion 2A that protrudes downward and fits into an upper end of a contact pressure spring 33 described later is integrally formed at the center of the lower surface of the movable contact 2. The movable contact 2 is sandwiched by a holding member 3 that holds a contact pressure spring 33.

  The holding member 3 includes a top plate 30 and a bottom plate 31 each formed in a rectangular plate shape, and a pair of side plates 32. The top plate 30 contacts the upper surface of the movable contact 2, and the bottom plate 31 faces the top plate 30 with the movable contact 2 and the contact pressure spring 33 interposed therebetween. The top plate 30 and the bottom plate 31 sandwich and hold the movable contact 2 and the contact pressure spring 33. One side plate 32 connects the front end portion of the top plate 30 and the front end portion of the bottom plate 31 in front of the movable contact 2. The other side plate 32 connects the rear end portion of the top plate 30 and the rear end portion of the bottom plate 31 behind the movable contact 2.

A positioning protrusion 31 </ b> A that protrudes upward and fits to the lower end of the contact pressure spring 33 is integrally formed at the center of the upper surface of the bottom plate 31. Further, from the bottom surface of the bottom plate 31, a cylindrical protrusion 31B protruding downward is integrally formed. A cylindrical boss 31C through which the upper end of the movable shaft 20 is inserted is integrally formed at the center of the bottom of the protrusion 31B. The movable shaft 20 is formed in the shape of a long bar along the vertical direction, and its upper end is fixed in the boss portion 31C.
The lower end portion of the movable shaft 20 is fixed to the movable core 7 in a state of being inserted into an insertion hole 70 of the movable core 7 described later.

  The contact pressure spring 33 is formed of a coil spring, and is positioned with respect to the bottom plate 31 by fitting the positioning protrusion 31A of the bottom plate 31 of the holding portion 3 to the inner diameter portion of the lower end portion thereof. Further, the contact pressure spring 33 is positioned with respect to the movable contact 2 by fitting the positioning protrusion 2 </ b> A of the movable contact 2 to the inner diameter portion of the upper end portion thereof. That is, the movable contact 2 and the contact pressure spring 33 are sandwiched by the top plate 30 and the bottom plate 31 of the holding member 3 along the extending and contracting direction of the contact pressure spring 33, and the contact pressure spring 33 is in a compressed state.

  The sealing container 4 includes a case 40 and a flange 41. The case 40 is formed in a hollow box shape whose bottom surface is opened from a heat-resistant material such as ceramic, and a pair of through holes 40A are provided through the top surface. And the upper edge of the flange 41 is joined to the opening periphery of the case 40 by brazing. Furthermore, the lower end edge of the flange 41 is joined to the upper surface of the first yoke plate 60 which will be described later, thereby completing the sealing container 4 that hermetically seals each contact portion including the pair of fixed contacts 10 and the movable contact 2. To do. Inside the sealing container 4, a mixed gas mainly containing hydrogen is sealed. For this reason, it is possible to cool the arc that is generated when the contact is opened and closed.

  A pair of plate-like permanent magnets 42 are fixed to the outer surfaces of the left and right walls of the case 40 as shown in FIGS. 1 (a) and 1 (b). These permanent magnets 42 generate a magnetic field B <b> 1 in the sealed container 4 in a direction from the rear to the front. Here, when the contacts are opened and closed, an arc current flows through each fixed contact 10 and the movable contact 2. In the present embodiment, using the Lorentz force generated by the arc current and the magnetic field B <b> 1 by the permanent magnet 42, the arc can be driven and stretched away from each contact portion.

  The electromagnet block B <b> 1 includes a coil bobbin 5 that winds the excitation winding 53, a yoke 6, a movable iron core 7, and a fixed iron core 8. The coil bobbin 5 is made of a resin material, and includes a cylindrical portion 50 around which the excitation winding 53 is wound, and a first flange portion 51 and a second flange portion 52 formed on both upper and lower ends of the cylindrical portion 50, respectively. On the upper surface of the first flange 51, a concave portion 51A that is recessed downward is provided. Further, the inner diameter on the lower end side of the cylindrical portion 50 is larger than the inner diameter on the upper end side.

  Excitation winding 53 has ends connected to a pair of terminal portions (not shown) provided on first flange 51. Each terminal portion is connected to a pair of coil terminals (not shown) via lead wires (not shown). Therefore, a current is supplied from the external power source to the excitation winding 53 via each coil terminal.

  The yoke 6 includes a first yoke plate 60 disposed on the upper end side of the coil bobbin 5, a second yoke plate 61 disposed on the lower end side of the coil bobbin 5, and the first yoke plate 60 side from the left and right ends of the second yoke plate 61. And a pair of third yoke plates 62 extending in the direction. The first yoke plate 60 is formed in a rectangular plate shape. An insertion hole 60 </ b> A is provided in the center of the first yoke plate 60.

  A cylindrical member 54 having a bottomed cylindrical shape with a flange 54A formed at the upper end is inserted through the insertion hole 60A. The flange portion 54A is joined to the bottom surface of the recess 51A. A movable iron core 7 formed in a cylindrical shape from a magnetic material is accommodated in the lower end portion in the cylindrical member 54. A fixed iron core 8 formed in a cylindrical shape from a magnetic material is accommodated in an upper end portion in the cylindrical member 54 so as to face the movable iron core 7. An insertion hole 70 is formed in the movable iron core 7 along the axial direction. The lower end portion of the movable shaft 20 is inserted into the insertion hole 70 and fixed. A first recess 71 that is recessed downward is provided at the upper end of the movable iron core 7. A second boss portion 83 of the fixed iron core 8 to be described later is fitted into the first recess 71. Furthermore, a second recess 70 </ b> A that is recessed downward is provided in the center of the first recess 71.

  A cylindrical fourth yoke plate 63 formed integrally with the second yoke plate 61 is fitted into a gap formed between the inner circumferential surface of the lower end portion of the coil bobbin 5 and the outer circumferential surface of the cylindrical member 54. doing. The fourth yoke plate 63 forms a magnetic circuit together with the yoke plates 60 to 62, the movable iron core 7, and the fixed iron core 8.

  A cylindrical first boss portion 80 that protrudes upward and passes through the insertion hole 60 </ b> A of the first yoke plate 60 is integrally formed on the upper surface of the fixed iron core 8. The holding member 3 is positioned by inserting the protrusion 31 </ b> B of the holding member 3 into the first boss 80. A cylindrical second boss portion 83 that protrudes downward and fits into the first recess 71 of the movable iron core 7 is integrally formed on the lower surface of the fixed iron core 8.

  The fixed iron core 8 is provided with an inner cylinder portion 81 that communicates with the first boss portion 80 and the second boss portion 83. A recess 81A having a slightly larger diameter is provided at the lower end of the inner cylinder 81, and the return spring 82 is housed in a space surrounded by the recess 81A and the second recess 70A of the movable iron core 7. ing. The return spring 82 is formed of a coil spring, the lower end of which is in contact with the bottom surface of the second recess 70 </ b> A of the movable core 7, and the upper end of which is in contact with the bottom surface of the recess 81 </ b> A of the fixed core 8. Therefore, the return spring 82 is housed in a compressed state between the bottom surface of the second recess 70A and the bottom surface of the recess 81A, and elastically biases the movable iron core 7 downward.

  Hereinafter, the opening / closing operation of the contact in this embodiment will be described with reference to FIG. In the present embodiment, the return spring 82 has a higher spring constant than the contact pressure spring 33. For this reason, the movable iron core 7 slides downward by the urging force of the return spring 82, and accordingly, the movable shaft 20 and the holding member 3 also move downward. The movable contact 2 is pressed downward by the top plate 30 of the holding unit 3 and moves downward. For this reason, the movable contact 2 is separated from each fixed contact 10 in the initial state.

  When the exciting winding 53 is energized, the movable iron core 7 is attracted to the fixed iron core 8 and slides upward. At this time, the movable shaft 20 and the holding member 3 connected to the movable iron core 7 also move upward in conjunction with each other. Thereby, since the top plate 30 of the holding part 3 moves upward, the top plate 30 is separated from the movable contact 2, and the restriction on the upward movement of the movable contact 2 is released. Then, the movable contact 2 moves upward by the biasing force of the contact pressure spring 33, and the movable contact 2 abuts on each fixed contact 10, and the contacts are conducted.

  When the energization to the excitation winding 53 is turned off, the attractive force of the fixed iron core 8 is lost, and the movable iron core 7 moves downward by the urging force of the return spring 82. At this time, the movable shaft 20 and the holding member 3 connected to the movable iron core 7 also move downward in conjunction with each other. Thereby, since the top plate 30 of the holding part 3 presses the movable contact 2 downward, the movable contact 2 and each fixed contact 10 are separated from each other, and the contacts are interrupted.

  By the way, in order to extinguish and interrupt the arc generated when the contact is opened and closed, it is necessary to make the arc voltage higher than the power supply voltage. Since the arc voltage increases as the arc length increases, the arc can be extinguished more reliably and the interruption performance can be improved by extending the arc as much as possible.

  However, if the magnetic field of the permanent magnet 42 is simply increased for the purpose of increasing the arc voltage to extinguish the arc more reliably, the problem to be solved by the invention may be re-ignited as already described.

  Therefore, in the present embodiment, as shown in FIG. 1B, the permanent magnets 42 provided on the left outer wall of the case 40 are arranged so that the front end is an N pole and the rear end is an S pole. . Similarly, the permanent magnet 42 provided on the right outer wall of the case 40 is disposed so that the front end portion is the S pole and the rear end portion is the N pole. That is, in the present embodiment, each permanent magnet 42 is arranged so that the magnetic field B1 applied to the arc increases as the distance from each contact portion increases.

  Hereinafter, as a specific example, arc extinction at the contact point on the right side will be described with reference to FIG. First, when the contacts are separated from each other, the arc current I0 flowing between the fixed contact 10 and the movable contact 2 and the magnetic field B1 directed from the rear to the front generated by the permanent magnet 42 are directed rightward. Lorentz force F0 is generated. By this Lorentz force F0, the arc generated between the contacts is stretched rightward, that is, away from the contact portion.

  Next, when the arc is stretched to the right inner wall of the case 40, a rightward arc current I1 flows through the arc near the end of the movable contact 2, and the arc near the end of the fixed terminal 1 A leftward arc current I2 flows. The arc near the end of the movable contact 2 is stretched downward by a downward Lorentz force F1 generated by the arc current I1 and the magnetic field B1 generated by the permanent magnet 42. Similarly, the arc in the vicinity of the end of the fixed terminal 1 is stretched upward by an upward Lorentz force F2 generated by the arc current I2 and the magnetic field B1 by the permanent magnet 42. Therefore, the arc extended to the right inner wall of the case 40 is further extended in both the upper and lower directions, thereby further increasing the arc length. Thereby, in this embodiment, since an arc can be extended and an arc voltage can be raised, an arc can be more reliably extinguished.

  Here, the permanent magnet 42 forms a magnetic field by the lines of magnetic force emitted from the N pole toward the S pole. The magnetic field B <b> 1 generated by the permanent magnet 42 becomes stronger as it gets closer to the permanent magnet 42, and becomes weaker as it gets away from the permanent magnet 42. In other words, the magnetic field B <b> 1 by the permanent magnet 42 becomes stronger as it moves away from the contact portion (approaching the case 40).

  Accordingly, in the vicinity of the contact portion, since the magnetic field B1 by the permanent magnet 42 is weak, the Lorentz force F0 is also weakened. For this reason, the arc generated between the contacts does not diffuse in a short time. That is, when the contacts are separated from each other, the arc is not extinguished until the contacts are sufficiently separated from each other, so that re-ignition can be prevented. On the other hand, when the arc approaches the case 40, the magnetic field B1 by the permanent magnet 42 becomes strong, so that the arc stretched to the inner wall of the case 40 is further stretched, and the arc can be extinguished more reliably.

  As described above, in this embodiment, each permanent magnet 42 is arranged so that the magnetic field B1 applied to the arc increases as the distance from each contact portion increases. For this reason, since the magnetic field B1 by the permanent magnet 42 is weak in the vicinity of the contact portion, the arc generated between the contacts does not diffuse in a short time. Therefore, since the arc is not extinguished until the contacts are sufficiently separated from each other, re-ignition can be prevented. Further, since the magnetic field generated by the permanent magnet 42 is strong at a position away from the contact portion, the arc stretched to a position away from the contact portion can be further extended, and the arc can be extinguished more reliably.

  In the present embodiment, one permanent magnet 42 is disposed on each of the left and right outer walls of the case 40. However, as shown in FIGS. Three permanent magnets 42 may be arranged in the drawing. In this configuration, the magnetic field B1 in the vicinity of the inner wall of the case 40 can be further strengthened by superimposing the magnetic fields B1 by the plurality of permanent magnets 42. Therefore, compared with the case where one permanent magnet 42 is provided for each contact portion, the arc extended to the inner wall of the case 40 can be further extended, and the interruption performance can be further improved.

  Further, as shown in FIGS. 4A and 4B, the permanent magnets 42 may be arranged so as to be embedded in the wall of the case 40. In this configuration, the distance between each permanent magnet 42 and the inner wall of the case 40 can be shortened as compared with the case where each permanent magnet 42 is disposed on the outer wall of the case 40. That is, in this configuration, the magnetic field B <b> 1 in the vicinity of the inner wall of the case 40 can be further increased as compared with the case where each permanent magnet 42 is disposed on the outer wall of the case 40. Therefore, compared with the case where each permanent magnet 42 is arranged on the outer wall of the case 40, the arc extended to the inner wall of the case 40 can be further extended, and the interruption performance can be further improved.

(Embodiment 2)
Hereinafter, a second embodiment of the contact device according to the present invention will be described with reference to the drawings. However, since the basic configuration of the present embodiment is common to that of the first embodiment, common portions are denoted by the same reference numerals and description thereof is omitted. In the present embodiment, as shown in FIG. 5, permanent magnets 42 are arranged on the left and right corners on the rear outer wall of the case 40 of the sealed container 4. The permanent magnet 42 provided on the left outer wall of the case 40 is disposed so that the front end portion is an N pole and the rear end portion is an S pole. Similarly, the permanent magnet 42 provided on the right outer wall of the case 40 is disposed so that the front end portion is the S pole and the rear end portion is the N pole. Each permanent magnet 42 may be directly fixed to the outer wall of the case 40 or may be fixed to the inner wall of the housing. In other words, in the present embodiment, each permanent magnet 42 is disposed at a position facing the case 40 (sealing container 4) and having the longest distance from each contact portion in the housing.

  In the first embodiment, as illustrated in FIG. 1B, the arc travel distance D <b> 1 is a distance from each contact portion to the left and right inner walls of the case 40. On the other hand, in the present embodiment, as shown in FIG. 5, the arc travel distance D <b> 2 is a distance from each contact portion to the inner corner of the case 40. Therefore, the arc travel distance D2 in the present embodiment is longer than the arc travel distance D1 in the first embodiment.

  As described above, in the present embodiment, the arc travel distance D <b> 2 is increased by disposing each permanent magnet 42 at a position where the distance from each contact portion is farthest among positions where the permanent magnets 42 can be disposed. be able to. Therefore, in the present embodiment, the arc length can be increased by an amount corresponding to the increase of the arc travel distance D2, so that the arc voltage can be increased to further improve the interruption performance.

(Embodiment 3)
Hereinafter, a third embodiment of the contact device according to the present invention will be described with reference to the drawings. However, since the basic configuration of the present embodiment is the same as that of the first or second embodiment, common portions are denoted by the same reference numerals and description thereof is omitted. In the present embodiment, as shown in FIG. 6A, curved surfaces in which the distance between each fixed contact 10 and the movable contact 2 becomes longer at the left and right ends of the movable contact 2 as the distance from each contact portion increases. Forming.

  For this reason, in this embodiment, compared with Embodiment 1, it becomes easy for the arc generated between the contacts to travel along the curved surface of the movable contact 2. Therefore, in the present embodiment, since the arc generated between the contacts is likely to diffuse, the time for the arc to stay near the contact portion can be shortened, and as a result, the arc can be extinguished quickly.

  As shown in FIG. 6B, inclined surfaces are formed on the left and right ends of the movable contact 2 such that the distance between each fixed contact 10 and the movable contact 2 increases as the distance from each contact portion increases. May be. Even with this configuration, the same effects as described above can be obtained.

  In the present embodiment, curved or inclined surfaces are formed at the left and right ends of the movable contact 2, but curved surfaces are formed at the left lower end of the left fixed terminal 1 and the right lower end of the right fixed terminal 1. Alternatively, an inclined surface may be formed. Even with this configuration, the same effects as described above can be obtained. Of course, both the fixed terminal 1 and the movable contact 2 may be formed with curved surfaces or inclined surfaces. In this case, the arc generated between the contacts is more easily diffused, which is preferable.

DESCRIPTION OF SYMBOLS 1 Fixed terminal 10 Fixed contact 2 Movable contact 4 Sealing container 42 Permanent magnet

Claims (6)

  A pair of fixed terminals each having a fixed contact; a pair of contact parts each including a movable contact contacting and separating the fixed contacts; a sealing container for hermetically sealing the contact parts; and the contact parts And a permanent magnet for driving the arc generated in the direction away from each contact portion, and the permanent magnet is arranged such that a magnetic field applied to the arc increases as the distance from the contact portion increases. Contact device to do.   The contact device according to claim 1, wherein a plurality of the permanent magnets are arranged for each of the contact portions.   The contact device according to claim 1, wherein the permanent magnet is embedded in a wall of the sealed container.   A housing for storing at least the sealing container and the permanent magnet is provided, and the permanent magnet is disposed at a position facing the sealing container and farthest from the contact portion in the housing. The contact device according to claim 1.   A curved surface in which a distance between the fixed contact and the movable contact increases as the distance from the contact portion increases at at least one end of the fixed terminal or the movable contact. The contact device according to any one of claims 1 to 4.   At least one of the fixed terminal and the movable contact is formed with an inclined surface in which the distance between the fixed contact and the movable contact increases as the distance from the contact portion increases. The contact device according to any one of claims 1 to 4.

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