JP2013246874A - Contact device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a contact device that quickly extinguishes arc generated when contacts are moved into and out of contact with each other.SOLUTION: A contact device includes a contact section, a sealing container 4, and a pair of permanent magnets 42. The contact section has: a pair of fixed terminals 1 that have respective fixed contacts 10; and a movable contactor 2 that is moved into and out of contact with the fixed contacts 10. The sealing container 4 hermetically seals the contact section. The permanent magnets 42 drive arc that is generated in the contact section, in a direction away from the contact section. First protrusions 92 (protruded sections) are provided on an inner wall of the sealing container 4 so as to face the contact section. Each first protrusion 92 has a tip end that faces the contact section and that is inclined so as to be at an acute angle to an arc driving direction.

Description

  The present invention relates to a contact device.

  Conventionally, an electromagnetic relay in which an insulating wall of a base is formed in the vicinity of a contact mechanism in which a fixed contact provided on a fixed contact terminal and a movable contact provided on a movable contact piece are detachably arranged is known, for example, It is disclosed in Patent Document 1. In the conventional example described in Patent Document 1, an insulating protrusion that forms a hidden surface is integrally formed on the upper surface of the insulating wall. And from the vicinity of this protrusion, the insulation protrusion protrudes to the side. This insulating protrusion is located in the vicinity of the side of the fixed contact and the movable contact.

  In this conventional example, an arc is generated when the movable contact contacts and separates from the fixed contact, and even if wear powder is scattered and accumulated on the inner wall surface of the base located on the side based on Fleming's left-hand rule, the hidden surface No wear powder adheres to the surface. For this reason, in this conventional example, it is possible to prevent insulation deterioration due to scattering and deposition of wear powder. In particular, since the insulating protrusions projecting from the side extend to the vicinity of the fixed and movable contacts, the scattered abrasion powder does not wrap around and adhere to the hidden surface, ensuring even more reliable insulation. Deterioration can be prevented.

Japanese Patent Laid-Open No. 11-260229

  However, the above-mentioned conventional example is intended to prevent insulation deterioration due to wear powder that is scattered and deposited with the occurrence of an arc, and there is no disclosure about the point of extinction by driving the arc. Absent.

  Further, the conventional example has the following problems. That is, when the arc is extinguished by driving the arc, it is necessary to extend the arc from the contact portion formed of the fixed contact and the movable contact to the inner wall of the sealed container. In that case, in the above-mentioned conventional example, since any insulating protrusion has a flat surface perpendicular to the driving direction of the arc, the arc is difficult to spread and the arc cannot be extinguished quickly. There was a problem.

  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 quickly extinguish an arc generated when a contact is made.

  The contact device according to the present invention includes a fixed terminal having a fixed contact, a contact portion including a movable contact contacting and separating from the fixed contact, a sealing container for hermetically sealing the contact portion, and an arc generated at the contact portion. And a pair of permanent magnets for driving in a direction away from the contact portion, and provided with a protrusion facing the contact portion on the inner wall of the sealing container, the protrusion facing the contact portion The leading end portion is inclined so as to form an acute angle with respect to the driving direction of the arc.

  In this contact device, it is preferable that a portion excluding the tip portion of the protrusion is formed in a long flat plate shape along the driving direction of the arc.

  In this contact device, it is preferable that the protrusion is formed of a conductive material.

  In this contact device, it is preferable that the protrusion is made of a molded product of a resin material, and the resin material has a property of adsorbing moisture in the air.

  In this contact device, it is preferable that the protrusion is made of a molded product of a resin material in which a substance containing moisture is mixed in its structure.

  In this contact device, it is preferable that a tip end portion of the protrusion is opposed to a center in a contact / separation direction between the fixed contacts and the movable contact.

  In this contact device, it is preferable that a plurality of the protrusions are provided in parallel along the contact / separation direction.

  In the present invention, a protruding portion that is inclined so that the tip portion forms an acute angle with respect to the arc driving direction is provided on the inner wall of the sealed container so as to face the contact portion. Therefore, in the present invention, since the arc is likely to spread along the inclined surface of the protrusion, it is possible to quickly extinguish the arc generated at the time of contact / separation of the contact.

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 seen from the front, (b) is a perspective view of an auxiliary member, (c) is the front of the conventional contact apparatus. It is principal part sectional drawing seen from. It is sectional drawing which shows the basic composition of the contact apparatus which concerns on this invention. BRIEF DESCRIPTION OF THE DRAWINGS It is a figure which shows arrangement | positioning of the permanent magnet in Embodiment 1 of the contact apparatus which concerns on this invention, (a) is sectional drawing seen from upper direction at the time of providing in the front and back both walls of a sealing container, (b) is sealing It is sectional drawing seen from upper direction at the time of providing in the both right and left walls of a container. It is a figure which shows Embodiment 2 of the contact apparatus which concerns on this invention, (a) is principal part sectional drawing seen from the front, (b) is a perspective view of an auxiliary member, (c) provides two or more 2nd protrusions. It is principal part sectional drawing seen from the front at the time of, and (d) is a perspective view of the auxiliary member at the time of providing two or more 2nd protrusions. It is a figure which shows Embodiment 3 of the contact apparatus which concerns on this invention, (a) is principal part sectional drawing seen from the front, (b) is a perspective view of an auxiliary member. It is a figure which shows Embodiment 4 of the contact device which concerns on this invention, (a) is principal part sectional drawing seen from the front, (b) is a perspective view of an auxiliary member.

(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 addition, in FIG. 2, illustration of the auxiliary member 9 mentioned later is abbreviate | omitted.

  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 iron core 7 in a state of being inserted into an insertion hole 70 of the movable iron 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 an insulating and heat-resistant material such as ceramic, and a pair of through holes 40A are formed 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, by joining the lower end edge of the flange 41 to the upper surface of the first yoke plate 60 described later, the sealing container 4 that hermetically seals the contact portions including the fixed contacts 10 and the movable contact 2 is completed. 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.

  Further, a pair of plate-like permanent magnets 42 are in contact with the outer surfaces of the front and rear walls of the case 40 as shown in FIG. These permanent magnets 42 generate a magnetic field B1 in the sealed container 4 in a direction from the rear permanent magnet 42 toward the front permanent magnet 42. Here, when the current I1 flows through the movable contact 2 when the contact is closed, an upward and downward arc current is generated between the fixed contact 10 and the movable contact 2 when the contact is opened and closed. Due to the arc current and the magnetic field B1, a left Lorentz force F1 acts on the arc current between the left fixed contact 10 and the movable contact 2. Similarly, a right-handed Lorentz force F <b> 1 acts on the arc current between the fixed contact 10 on the right side and the movable contact 2. By this Lorentz force F1, the arc can be driven and stretched away from the 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. Further, 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 communicating 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. doing. 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 recessed portion 70 </ b> A of the movable iron core 7, and the upper end of which is in contact with the bottom surface of the recessed portion 81 </ b> A of the fixed iron core 8. Accordingly, 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, in the initial state in which the excitation winding 53 is not energized, the movable iron core 7 is urged downward by the urging force of the return spring 82 and is stationary at a predetermined position. In addition, the movable shaft 20 connected to the movable iron core 7, the holding member 3, and the movable contact 2 held by the holding member 3 also move downward and are stationary at a predetermined position. For this reason, the movable contact 2 is separated from each fixed contact 10 in the initial state.

  When the excitation 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 connected to the movable iron core 7, the holding member 3, and the movable contact 2 held by the holding member 3 also move upward in conjunction with each other. Thereby, although the movable contact 2 contacts each fixed contact 10, the movable iron core 7, the movable shaft 20, and the holding member 3 move slightly upward from this state. Then, the contact pressure spring 33 is compressed, and the movable contact 2 strongly contacts each fixed contact 10 by the urging force of the contact pressure spring 33, and the contacts are conducted.

  When the energization to the exciting 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 biasing 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 this arc voltage becomes larger as the arc length becomes longer, the arc can be extinguished quickly by extending the arc in the shortest possible time, and as a result, the interruption performance can be improved. Therefore, in the present embodiment, as already described, the permanent magnets 42 are provided on the outer surfaces of the front and rear walls of the sealed container 4. The arc is extended toward the left and right inner walls of the sealed container 4 by using the Lorentz force F1 generated thereby.

  However, when the arc generated in a circuit having a higher power supply voltage is extinguished, the arc length necessary for quickly extinguishing the arc is ensured by simply extending the arc toward the left and right inner walls of the sealed container 4. I can't. Therefore, it is conceivable to increase the arc length along the inner wall of the sealing container 4 by enlarging the sealing container 4, but this configuration has a problem that the contact device is enlarged.

  As other means, it is conceivable to provide an insulating protrusion on the inner wall of the sealed container as in the conventional example. However, in this configuration, since the insulating protrusion has a flat surface perpendicular to the driving direction of the arc, there is a problem that the arc is difficult to spread and the arc cannot be extinguished quickly.

  Therefore, in the present embodiment, the auxiliary member 9 is disposed in the sealed container 4 in order to solve the above-described problems. As shown in FIG. 1B, the auxiliary member 9 includes a bottom wall portion 90 and a pair of side wall portions 91. The bottom wall portion 90 is formed in a rectangular plate shape and abuts on the upper surface of the first yoke plate 60. A through hole 90 </ b> A for avoiding the first boss portion 80 of the fixed iron core 8 is provided through the center portion of the bottom wall portion 90. Each side wall portion 91 is formed in a rectangular plate shape, and protrudes upward from both left and right end portions of the bottom wall portion 90. Further, each side wall portion 91 comes into contact with the left and right inner walls of the sealing container 4.

  Each side wall 91 is integrally formed with a first protrusion 92 (projection) having a triangular cross section when viewed from the front-rear direction. The first protrusion 92 on the left side faces the contact portion formed by the left fixed contact 10 and the movable contact 2 when the auxiliary member 9 is disposed in the sealing container 4. Further, the first projection 92 on the right side faces the contact portion formed by the right fixed contact 10 and the movable contact 2. The tip of each first protrusion 92 is inclined so as to form an acute angle with respect to the arc driving direction (left-right direction). Moreover, the front-end | tip part of each 1st protrusion 92 opposes the center in the contact / separation direction (up-down direction) between contacts.

  Therefore, in the present embodiment, as shown in FIG. 1A, the arc stretched toward the left and right inner walls of the sealed container 4 by the Lorentz force F1 extends along the inclined surface of each first protrusion 92. For this reason, in this embodiment, compared with the conventional contact device (refer FIG.1 (c)) which does not arrange | position the auxiliary member 9, arc length can be extended, without enlarging an apparatus. Further, each of the first protrusions 92 of the present embodiment does not have a flat surface perpendicular to the arc driving direction as in the conventional insulating protrusion, and the tip portion facing the contact portion is the arc driving direction. It is inclined to make an acute angle with respect to. For this reason, in this embodiment, since an arc is easy to spread along the inclined surface of each 1st protrusion 92, an arc can be extended quickly and can be extinguished, and interruption | blocking performance can be improved.

  In the present embodiment, the tip of each first protrusion 92 faces the center in the contact / separation direction between the contacts, so that the arc spreads evenly on the inclined surfaces on both the upper and lower sides of each first protrusion 92. Therefore, in the present embodiment, the arc can be efficiently stretched and the interruption performance can be further improved as compared with the case where the arc is diffused to be inclined to any one of the inclined surfaces of the first protrusions 92. .

  In the present embodiment, the first protrusion 92 is provided by arranging the auxiliary member 9. However, the first protrusion 92 may be integrally formed on the left and right inner walls of the sealing container 4.

  Incidentally, as shown in FIG. 3B, each permanent magnet 42 may be provided on the outer surfaces of the left and right walls of the sealed container 4. In this configuration, a magnetic field B <b> 1 is generated in the sealed container 4 in a direction from the left permanent magnet 42 toward the right permanent magnet 42. Therefore, a forward (downward in the figure) Lorentz force F1 acts on the arc generated between the left fixed contact 10 and the movable contact 2. Further, a backward (upward in the figure) Lorentz force F1 acts on the arc generated between the fixed contact 10 on the right side and the movable contact 2. Therefore, the left part of the front wall of the sealed container 4 and the right part of the rear wall respectively oppose the arc driving direction.

  Therefore, in this configuration, instead of providing the first protrusions 92 on the left and right inner walls of the sealing container 4, the first protrusions 92 are provided on the left part of the front wall and the right part of the rear wall, respectively. Thereby, even with this configuration, the same effects as described above can be obtained. In addition, each 1st protrusion 92 may be provided by arrange | positioning the auxiliary member 9 in the sealing container 4 similarly to the above, and may be formed integrally with the inner wall of the sealing container 4.

(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 FIGS. 4A and 4B, the second protrusions 93 (protrusions) are provided on the respective side wall portions 91 of the auxiliary member 9 instead of the first protrusions 92.

  Each of the second protrusions 93 has a triangular shape when viewed from the front-rear direction at the tip, and the portion excluding the tip is formed as a long rectangular flat plate along the arc drive direction. Yes. When the auxiliary member 9 is disposed in the sealing container 4, the second protrusion 93 on the left side faces the contact portion formed by the left fixed contact 10 and the movable contact 2. Further, the second protrusion 93 on the right side is opposed to a contact portion made up of the right fixed contact 10 and the movable contact 2. The tip of each second protrusion 93 is inclined to form an acute angle with respect to the arc driving direction. Moreover, the front-end | tip part of each 2nd protrusion 93 opposes the center in the contact / separation direction between contacts.

  Accordingly, in the present embodiment, as shown in FIG. 4A, the arc stretched toward the left and right inner walls of the sealed container 4 by the Lorentz force F <b> 1 extends along each second protrusion 93. For this reason, in this embodiment, the arc length can be extended without increasing the size of the apparatus as in the first embodiment. Moreover, in this embodiment, since an arc is easy to spread along the inclined surface of the front-end | tip part of each 2nd protrusion 93, an arc can be extended quickly and can be extinguished and interruption | blocking performance can be improved.

  Furthermore, in this embodiment, since the tip of each second protrusion 93 faces the center in the contact / separation direction between the contacts, the arc spreads evenly on the inclined surfaces on both the upper and lower sides of each second protrusion 93. Therefore, in this embodiment, the arc can be efficiently stretched as in the first embodiment, and the interruption performance can be further improved.

  Incidentally, as shown in FIGS. 4C and 4D, a plurality of second protrusions 93 may be integrally formed in parallel along the vertical direction on each side wall portion 91 of the auxiliary member 9. In this configuration, since the arc length can be further extended by increasing the number of the second protrusions 93, the interruption performance can be further improved.

(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 common to that of the first embodiment, common portions are denoted by the same reference numerals and description thereof is omitted. In this embodiment, as shown in FIGS. 5A and 5B, a third protrusion 94 (protrusion) is provided on each side wall 91 of the auxiliary member 9 instead of the first protrusion 92.

  Each third protrusion 94 is made of a conductive material. Further, a plurality of third protrusions 94 are provided in parallel on the side wall portions 91 along the vertical direction. Note that the third protrusions 94 are electrically independent from each other.

  As for each 3rd protrusion 94, the cross section seen from the front-back direction is the triangular shape, and the site | part except the front-end | tip part is formed in the rectangular flat plate shape. The third protrusion 94 on the left side faces the contact portion formed by the left fixed contact 10 and the movable contact 2 when the auxiliary member 9 is disposed in the sealing container 4. The third protrusion 94 on the right side is opposed to a contact portion made up of the right fixed contact 10 and the movable contact 2. The tip of each third protrusion 94 is inclined to form an acute angle with respect to the arc driving direction.

  Therefore, in this embodiment, as shown in FIG. 5A, the arc stretched toward the left and right inner walls of the sealed container 4 by the Lorentz force F1 is divided by the third protrusions 94 that are electrically independent from each other. Is done. Here, the arc voltage is represented by the sum of the cathode fall voltage and the anode fall voltage and a voltage proportional to the arc length. When the arc is divided, the cathode fall voltage and the anode fall voltage are divided by the divided number. The sum of increases. Therefore, in this embodiment, the arc voltage can be increased by dividing the arc by the third protrusions 94, and the interruption performance can be improved.

  Further, in the present embodiment, as in the first and second embodiments, since the arc is likely to spread along the inclined surface of the tip portion of each third protrusion 94, the arc can be quickly stretched and extinguished, and the interruption performance Can be improved.

  In the present embodiment, a plurality of third protrusions 94 are provided on each side wall 91 of the auxiliary member 9. However, the same applies to the case where one third protrusion 94 is provided on each side wall 91. The effect of can be produced. Of course, if a plurality of third protrusions 94 are provided, the number of arc divisions also increases, so that the arc voltage can be increased to improve the interruption performance.

(Embodiment 4)
Hereinafter, a contact device according to a fourth embodiment of 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 FIGS. 6A and 6B, instead of the first protrusions 92, the fourth protrusions 95 (protrusions) having a triangular cross section when viewed from the front-rear direction are provided on the side wall portions. 91 respectively.

  Each of the fourth protrusions 95 is made of a molded product of a polyamide (nylon) resin material such as PA6, PA46, and PA66. These resin materials have the property of adsorbing moisture in the air (hygroscopicity), and release the moisture adsorbed on the resin materials when placed in a high-temperature atmosphere, for example, by being exposed to a high-temperature arc. The fourth protrusion 95 on the left side faces the contact portion composed of the left fixed contact 10 and the movable contact 2 when the auxiliary member 9 is disposed in the sealing container 4. Further, the fourth protrusion 95 on the right side faces a contact portion formed by the right fixed contact 10 and the movable contact 2. The tip of each fourth protrusion 95 is inclined to form an acute angle with respect to the arc driving direction. Moreover, the front-end | tip part of each 4th protrusion 95 opposes the center in the contact / separation direction between contact points.

  Here, when the temperature of each fixed contact 10 or the movable contact 2 rises due to arc discharge accompanying opening and closing of the contact, each fixed contact 10 and the movable contact 2 may melt and a large amount of metal vapor MV1 may be generated. . When the metal vapor MV1 is filled in the vicinity of the contact portion, there is a possibility that the contact breaking performance may be deteriorated, or the insulation performance between the contacts may be deteriorated to cause re-ignition.

  In the present embodiment, as shown in FIG. 6B, when each fourth protrusion 95 is exposed to a high-temperature arc, moisture adsorbed from the inclined surface of each fourth protrusion 95 is released. And metal vapor | steam MV1 can be kept away from a contact part by pushing out metal vapor | steam MV1 with the discharge | released water | moisture content. Therefore, in this embodiment, it can suppress that metal vapor | steam MV1 fills the vicinity of a contact part, and can prevent the deterioration of interruption | blocking performance and re-ignition.

  In addition, hydrogen is generated when the adsorbed moisture is decomposed by the heat of the arc, but hydrogen has the property of cooling the arc. Therefore, in the present embodiment, the arc can be extinguished more quickly than in the first embodiment.

  Each fourth protrusion 95 may be a molded product of a resin material in which a substance containing a large amount of water in the form of hydrated water or the like is mixed in its own structure such as magnesium hydroxide or magnesium borate. In this configuration, since the water contained in each of the fourth protrusions 95 is decomposed by the heat of the arc, hydrogen is generated, so that the arc can be extinguished quickly as described above.

  Moreover, since the shape of each 4th protrusion 95 of this embodiment is the same shape as the 1st protrusion 92 of Embodiment 1, there can exist an effect similar to Embodiment 1. FIG.

DESCRIPTION OF SYMBOLS 1 Fixed terminal 10 Fixed contact 2 Movable contact 4 Sealing container 42 Permanent magnet 9 Auxiliary member 92 1st protrusion (projection)

Claims (7)

  A fixed terminal having a fixed contact; a contact part comprising a movable contactor contacting and separating from the fixed contact; a sealing container that hermetically seals the contact part; and a direction in which an arc generated at the contact part is separated from the contact part. A pair of permanent magnets for driving the inner wall of the sealed container, and a protrusion that faces the contact portion is provided on the inner wall of the sealed container, and the protrusion has a tip that faces the contact portion of the arc. A contact device that is inclined to form an acute angle with respect to a driving direction.   2. The contact device according to claim 1, wherein a portion of the protrusion excluding the tip is formed in an elongated flat plate shape along a driving direction of the arc.   The contact device according to claim 2, wherein the protrusion is made of a conductive material.   The contact device according to claim 1, wherein the protrusion is formed of a molded product of a resin material, and the resin material has a property of adsorbing moisture in the air.   2. The contact device according to claim 1, wherein the protrusion is made of a molded product of a resin material in which a substance containing moisture is mixed in its structure.   6. The contact device according to claim 1, wherein a tip portion of the projecting portion is opposed to a center in a contact / separation direction between each of the fixed contacts and the movable contact.   The contact device according to claim 1, wherein a plurality of the protrusions are provided in parallel along the contact / separation direction.

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