JP2005038706A - Sealed contact device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a sealed contact device capable of improving responsiveness. <P>SOLUTION: The sealed contact device is provided with a fixed terminal 2 having a fixed contact 2a, a movable contact element 3 having a movable contact 3a coming in and out of contact with the fixed contact 2a, and a movable iron core 8 coupled with the movable contact element 3 through a shaft 4 and driven by an electromagnet. The movable iron core 8, the movable contact element 3, and the fixed contact 2a are tightly sealed. A space housing the movable iron core 8 and that housing the movable contactor 3 are partitioned by a first junction member 11 through which the shaft 4 is put. A gap between the first junction member 11 and the shaft 4 is covered with an elastic cover 17. Grooves 17b for forming a gap communicating the space housing the movable iron core 8 with that housing the movable contact element 3 against the first junction member 11 are fitted to the elastic cover 17. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a sealed contact device suitable for a power load relay, an electromagnetic switch or the like.

  Conventionally, in order to shorten the duration of an arc generated between contacts, a sealed contact device in which a gas is sealed in a space in which the contacts are stored has been provided (for example, see Patent Document 1).

  An example of this type of sealed contact device is shown in FIG. The sealed contact device includes a sealed contact portion A, a drive unit B, and a housing C. First, the sealing contact portion A will be described. A box-shaped fixed terminal holding member 1 whose one surface is opened is formed of a heat-resistant material such as ceramic, and through holes 1a are provided at two locations on the bottom thereof. The fixed terminals 2 and 2 partially inserted into the through holes 1a and 1a are formed in a substantially multi-stage bottomed cylindrical shape by, for example, a copper-based material, and the fixed contact 2a is fixed to one end portion on the bottom side. A flange 2c is provided at the other end on the opening side. Note that the fixed contact 2 a may be provided integrally with the fixed terminal 2. The fixed terminal 2 is hermetically joined to the fixed terminal holding member 1 by brazing or the like in the vicinity of the flange 2c with the other end protruding from the fixed terminal holding member 1. Further, a thread groove 2b is formed from the opening side of the fixed terminal 2 inward.

  The movable contact 3 is formed, for example, in a flat plate shape by using a copper-based material or the like, and the movable contact 3a is fixed to both ends with a distance to and away from the fixed contact 2a. The movable contact 3 a may be provided integrally with the movable contact 3. An insertion hole 3b is provided at the center of the movable contact 3, and one end 4a of the shaft 4 formed in a substantially round bar shape by an insulating material is inserted into the insertion hole 3b. Further, a thread groove 4 c is cut in the other end 4 b of the shaft 4.

  A movable contact holder 5 is connected to one end 4a of the shaft 4 through which the insertion hole 3b of the movable contact 3 is inserted. The movable contact 3 is a compression spring composed of a coil spring, and is held by the movable contact holder 5 together with a contact pressure spring 6 that applies contact pressure between the movable contact 3a and the fixed contact 2a. More specifically, the movable contact holder 5 includes a central piece 5a connected to one end 4a of the shaft 4, a pair of side pieces 5b protruding from the central piece and facing each other with the movable contact 3 interposed therebetween, And a support piece 5d that protrudes from the tip of the side piece 5b and is located on the opposite side of the center piece 5a with the movable contact 3 interposed therebetween, and supports the contact pressure spring 6. One end of the contact pressure spring 6 is in elastic contact with the support piece 5d, and the other end is in elastic contact with the surface opposite to the surface of the movable contact 3 on which the movable contact 3a is provided.

  The shaft 4 has an insertion hole 7b penetrating in the axial direction of the fixed iron core 7 formed in a substantially cylindrical shape, and an insertion hole 8a penetrating in the axial direction of the movable iron core 8 formed in a substantially cylindrical shape. And a compression spring composed of a coil spring, which is disposed between the fixed iron core 7 and the movable iron core 8 and is inserted into a return spring 9 that urges the movable iron core 8 in a direction away from the fixed iron core 7. Yes. A thread groove 8b that is screwed into the thread groove 4c of the shaft 4 is cut on the inner peripheral surface of the insertion hole 8a of the movable iron core 8, and the shaft 4 is threaded into the thread groove 8b of the movable iron core 8. It is fixed to the movable iron core 8 with an adhesive or the like. The fixed iron core 7 is fixed to the housing C via a first joining member 11 and a yoke 15 which will be described later.

  The fixed iron core 7, the movable iron core 8, and the return spring 9 are made of a bottomed cylindrical portion 10 that is formed of a nonmagnetic material and has a cylindrical portion 10 a and a bottom portion 10 b. The cores 7 are respectively stored so as to be located on the bottom portion 10b side.

  The first joining member 11 is formed in a rectangular shape by a magnetic metal material such as iron, and forms a magnetic circuit together with the fixed iron core 7 and the movable iron core 8. The first joining member 11 is provided with an insertion hole 11a through which the first end of the fixed iron core 7 in the axial direction is fixed, and the vicinity of the insertion hole 11a is hermetically joined to the bottomed cylindrical part 10. . The 2nd joining member 12 is formed in the cylinder shape with the metal material, and the step 12d which makes the internal diameter of the other end part side larger than the one end part side is provided. One end of the second joining member 12 on the side having a smaller inner diameter is hermetically joined to the opening end of the fixed terminal holding member 1, and the other end is opposite to the surface on which the bottomed cylindrical part 10 of the first joining member 11 is joined. Airtightly joined to the surface. The second joining member 12 accommodates the fixed terminal holding member 1, the first joining member 11, and the bottomed cylindrical portion 10, as well as the fixed contact 2 a, the movable contact 3 a, the fixed iron core 7, and the movable iron core 8. A sealed container that forms the airtight space 30 is configured. In this airtight space 30, a gas mainly composed of hydrogen is sealed, for example, at about 2 atm.

  Next, the drive unit B will be described. The drive unit B includes a coil frame 14 disposed around the bottomed tube unit 10, a coil 13 wound around the coil frame 14, and a yoke 15, and includes a shaft 4, a fixed iron core 7, and a movable iron. The driving means is configured together with the core 8 and the first joining member 11. The yoke 15 includes a yoke body 15 a and a bush 15 b, and forms a magnetic circuit together with the fixed iron core 7, the movable iron core 8, and the first joining member 11. The yoke body 15a is formed in a U shape with a central piece and both opposing pieces so as to surround the coil 13, and a through hole 15c is provided in the central piece. The bush 15b is formed in a cylindrical shape and is inserted into the through hole 15c of the yoke body 15a. In the state where the yoke body 15a and the bush 15b are disposed, the above-described tube portion 10a of the bottomed tube portion 10 is located between the bush 15b of the yoke 15 and the movable iron core 8.

  Finally, the housing C will be described. The housing C is made of a synthetic resin molded product having an insulating property and accommodates both the sealed contact portion A and the drive portion B. The housing C is provided with an insertion hole 16 through which the fixed terminal 2 is inserted, and holds the fixed terminal 2 inserted through the insertion hole 16 so that the flange portion 2c protrudes from the outer surface (the upper surface in FIG. 7). . The protruding fixed terminal 2 is connected to a bus bar for electric wire connection (not shown).

  The conventional sealed contact device configured as described above operates as follows. Before the excitation of the coil 13, the movable contact 3a faces the fixed contact 2a with a contact gap L1. When the coil 13 is excited, the movable iron core 8 is attracted to and moved by the fixed iron core 7, so that the shaft 4 connected to the movable iron core 8 is driven, and the contact gap L1 is gradually reduced. It contacts the fixed contact 2a. Thereafter, when the shaft 4 is further driven, the movable iron core 8 moves by the amount of overtravel, and the spring load of the contact pressure spring 6 is further increased. The total of the contact gap L1 and the overtravel amount is the stroke of the movable iron core 8.

When the excitation of the coil 13 is cut off, the movable contact 3 returns mainly by the urging force of the contact pressure spring 6 and the return spring 9, the movable contact 3a is separated from the fixed contact 2a, and the movable iron core 8 is moved. Also return by a predetermined distance and return to the original state.
The protruding fixed terminal 2 is connected to a bus bar for electric wire connection (not shown).

By the way, in the above conventional example, a part of the contacts 2a and 3a is scattered by the arc generated when the contacts are opened and closed, and the scattered contact powder passes through the gap between the shaft 4 and the fixed iron core 7 to move the movable iron core 8. There is a risk that the movement of the movable iron core 8 may be suppressed when it reaches. Therefore, Patent Document 1 discloses that an elastic cover that covers a gap formed between the shaft 4 and the fixed iron core 7 is provided to prevent contact powder from entering the space in which the movable iron core 8 is accommodated by the elastic cover. Are listed.
Japanese Patent Laid-Open No. 11-232986 (Pages 2-3 and 7, FIGS. 10 and 12)

  However, since the conventional elastic cover also blocks the gas in and out between the space in which the movable contact 3 is accommodated and the space in which the movable iron core 8 is accommodated, the movable iron core is opened by air damping when the contacts are opened and closed. Responsiveness has been reduced by increasing the resistance force acting on 8 and thus decreasing the moving speed of the movable iron core 8.

  This invention is made | formed in view of the said reason, The objective is to provide the sealing contact apparatus which can improve responsiveness.

  The invention of claim 1 includes a fixed terminal provided with a fixed contact, a movable contact provided with a movable contact contacting and separating from the fixed contact, a shaft having one end connected to the movable contact, and the other end of the shaft. A movable iron core connected to the electromagnet, an electromagnet for driving the movable iron core in the axial direction of the shaft, and holding the fixed terminal so that the fixed contact is exposed to the inside, and the movable contactor, the movable iron core and the shaft are sealed. A sealing container that is housed in a state, a shaft insertion hole through which a shaft is inserted, and a space inside the sealing container into a space that houses a movable iron core and a space that houses a movable contact The partition body is formed in a cylindrical shape with an elastic material, and one end portion is connected to the partition body so as to surround the entire circumference of the opening of the shaft insertion hole, and the inner peripheral surface of the other end portion is elastic on the entire circumference of the shaft. And a movable iron core A storage spaces and a movable contact is accommodated space, characterized in that a vent for communicating via the shaft insertion hole in the elastic cover.

  According to the present invention, when the movable contactor operates, the gas in the sealing container is inserted between the ventilation part and the shaft between the space in which the movable iron core is accommodated and the space in which the movable contactor is accommodated. Since it enters and exits through the hole, it is possible to reduce the resistance force acting on the movable iron core by air damping when the contact is opened and closed, thereby improving the responsiveness.

  According to a second aspect of the present invention, in the first aspect of the present invention, the elastic cover includes a buffer portion positioned between the movable contact and the partition.

  According to this invention, since the sound at the time of contact opening / closing is absorbed by the buffer portion of the elastic cover, noise can be reduced.

  According to a third aspect of the present invention, in the first aspect of the present invention, the movable iron core is provided with a communication portion for communicating spaces on both sides of the movable iron core in the axial direction of the shaft.

  According to the present invention, it is possible to further reduce the resistance force acting on the movable iron core by air damping at the time of opening and closing the contact, further improving the operation speed of the movable iron core, and further improving the responsiveness of the contact opening and closing.

  According to a fourth aspect of the present invention, the movable contact is coupled to the shaft via a holding member that holds a contact pressure spring that applies a contact pressure to the movable contact, and the holding member abuts the movable contact to the shaft. And a rotation prohibiting portion that prohibits the rotation of the movable contact in a plane orthogonal to the axial direction.

  According to the present invention, rattling of the movable contact with respect to the holding member is suppressed, and the movable contact can be operated smoothly. Further, since the position of the movable contact is stabilized by stabilizing the position of the movable contact, the contact area between the movable contact and the fixed contact when the contact is closed can be kept constant.

  According to the present invention, the elastic cover is provided with the ventilation portion for communicating the space containing the movable iron core and the space containing the movable contact through the shaft insertion hole. The gas in the sealing container enters and exits through the ventilation portion and the shaft insertion hole between the space in which the movable iron core is accommodated and the space in which the movable contact is accommodated. Resistive force acting on the movable iron core can be reduced, thereby improving responsiveness.

  The best mode for carrying out the present invention will be described below with reference to the drawings. Since the basic configuration of the present embodiment is the same as that of the conventional example, common portions are denoted by the same reference numerals, and illustration and description thereof are omitted.

  As shown in FIG. 1, the present embodiment includes an elastic cover 17 made of an elastic material such as silicon rubber and covering the gap between the first joining member 11 and the shaft 4, and the movable contact 3 is accommodated. The elastic cover 17 is provided with a ventilation portion that communicates the formed space and the space in which the movable iron core 8 is stored. Further, the yoke body 15a and the bush 15b are integrated. Further, the first joining member 11 is configured to function also as the fixed iron core 7 in the conventional example, and a shaft insertion hole 11b through which the shaft 4 is inserted penetrates the central portion of the first joining member 11. The return spring 9 is elastically contacted around the shaft insertion hole 11 b of the first joint portion 11. That is, the first joining member 11, the coil 13, the coil frame 14, and the yoke 15 constitute an electromagnet that drives the movable iron core 8. The first joining member 11 is also a partition that partitions the space in which the movable iron core 7 is stored and the space in which the movable contact 3 is stored. Further, the structure of the movable contact holder 5 as a holding member is also different from that of the conventional example. As shown in FIG. 2, a base portion 5e connected to the shaft 4 and two pieces protruding from the base portion 5e and facing each other. The holding piece 5f and a holding piece 5g suspended between the tips of the holding pieces 5f are provided. The movable contact 3 has a rectangular plate shape, and is held by the movable contact holder 5 with both end surfaces in the short direction facing the holding piece 5f. The contact pressure spring 6 is provided between the movable contact 3 and the base 5e of the movable contact holder 5, and biases the movable contact 3 so as to press it against the pressing piece 5g. Spherical projections 5h are respectively provided on the surfaces of the both ends of both holding pieces 5f away from the other holding piece 5f in the direction orthogonal to the axial direction of the shaft 4 (left and right direction in FIG. 2). ing. The tips of the protrusions 5 h are in sliding contact with the inner surface of the fixed terminal holding member 1, so that the orientation of the movable contact holder 5 with respect to the fixed terminal holding member 1 is stabilized. In addition, ribs 5i that are long in the axial direction of the shaft 4 are provided on the opposing surfaces of both end portions of both holding pieces 5f in a direction perpendicular to the axial direction of the shaft 4 (left and right direction in FIG. 2), for example, by bending. It is. The tip of each rib 5 i is in sliding contact with the end surface of the movable contact 3 in the short direction, so that the rotation of the movable contact 3 in the plane orthogonal to the axial direction of the shaft 4 is prohibited.

  Here, in the case where the rib 5i is not provided, if unevenness is present on the side surface of the movable contact 3, the contact area between the movable contact 3 and the movable contact holder 5 is reduced, so that the movable contact 3 There is a possibility that the posture with respect to the movable contact holder 5 is not stable, and that only one movable contact 3a is in contact with the fixed contact 2a, resulting in an operation failure or a decrease in responsiveness. In order to prevent such a situation, it is necessary to maintain the processing accuracy of the movable contact 3 high, resulting in an increase in manufacturing cost. For example, when the movable contact 3 rotates relative to the movable contact holder 5 in a plane orthogonal to the axial direction of the shaft 4, the contact pressure between the movable contact 3 and the movable contact holder 5 is increased. When it becomes higher, a strong frictional force acts between the movable contact 3 and the movable contact holder 5, and the movable contact 3 is caught by the movable contact holder 5, so that the responsiveness is lowered or the movable contact is lowered. If the position of 3a is shifted, the contact area between the movable contact 3a and the fixed contact 2a may be reduced, and the contact resistance may be increased.

  On the other hand, since the posture of the movable contact 3 with respect to the movable contact holder 5 is stabilized by providing the rib 5i in the present invention, even if some unevenness is present on the side surface of the movable contact 3, the operation failure or No decrease in responsiveness occurs. In addition, since the position of the movable contact 3 is stabilized by stabilizing the position of the movable contact 3, the contact area between the movable contact 3a and the fixed contact 2a when the contact is closed can be kept substantially constant. Furthermore, since the rib 5i is formed long in the axial direction of the shaft 4, even if the movable contact 3 moves in the axial direction of the shaft 4 with respect to the movable contact holder 5, the rib 5i with respect to the rib 5i of the movable contact 3 The contact position and contact area are kept substantially constant. In addition, since the ribs 5 i come into contact with both ends of the movable contact 3 in the direction perpendicular to the axis of the shaft 4, the ribs 5 i come into contact with the central part of the movable contact 3 in the direction perpendicular to the axis of the shaft 4. Compared with the case where it does, rotation with respect to the movable contact holder 5 of the movable contact 3 can be prevented more effectively.

  Next, the shape of the elastic cover 17 will be described in detail. As shown in FIGS. 3 and 4, the elastic cover 17 is formed in a cylindrical shape in which one opening is larger than the other opening, and the periphery of the opening on the small side is formed thick, and the opening on the small side is formed. The inner peripheral surface of the shaft 4 is in elastic contact with the entire outer periphery of the shaft 4. In addition, an annular piece 17a is provided on the outer periphery of the opening on the larger side of the elastic cover 17 over the entire periphery. In the elastic cover 17, the opening-side surface of the annular piece 17 a is adhered to the periphery of the shaft insertion hole 11 b on the contact-side surface (the upper surface in FIG. 1) of the first joining member 11 with, for example, an adhesive. Thus, the first joint member 11 is coupled. Here, a plurality of (four in the figure) grooves 17b communicating with the outer periphery and the inner periphery of the annular piece 17a are provided on the joining surface of the annular piece 17a with respect to the first joining member 11, respectively. As shown in FIG. 5, between the first coupling member 11 and the elastic cover 17, a space in which the movable contact 3 is accommodated and a space in which the movable iron core 8 is accommodated are interposed via a shaft insertion hole 11b. A gap for communicating with each other is formed at the position of the groove 17 b of the elastic cover 17. That is, the groove 17b is a communication part. Here, the width dimension and the depth dimension of the groove 17b are set so that the gap can pass the gas while preventing the contact powder from passing therethrough.

  Further, a protrusion 5j that elastically contacts the annular piece 11a of the elastic cover 17 when the contact is opened protrudes from the surface of the base 5e of the movable contact holder 5 facing the first joining member 11. That is, the annular piece 17a is a buffer part. With this configuration, noise due to the collision between the movable contact holder 5 and the first joining member 11 is reduced, and the manufacturing cost can be reduced as compared with a case where a component for reducing noise is separately prepared. The shape of the contact surface of the protrusion 5j with respect to the annular piece 11a is a curved surface. With this configuration, the contact area between the protrusion 5j and the annular piece 17a continuously changes in the process of opening the contact. Therefore, the effect of suppressing noise is improved as compared with the case where the protrusion 5j and the annular piece 17a are in contact with each other in a plane. To do. Other configurations and operations are the same as those of the conventional example.

  According to the above configuration, when the movable contact 3 operates, the groove 17b of the elastic cover 17 and the first space between the space in which the movable iron core 8 is accommodated and the space in which the movable contact 3 is accommodated. Since gas enters and exits through the shaft insertion hole 11b of the joining member 11, the resistance force acting on the movable iron core 8 by air damping at the time of opening and closing the contact can be reduced, thereby improving the responsiveness.

  Furthermore, as shown in FIG. 6, the outer peripheral surface of the movable iron core 8 of the present embodiment is provided with a notch 8c over the entire length in the axial direction. Between the part where the notch 8c of the movable iron core 8 is provided and the inner peripheral surface of the bottomed cylindrical portion 10, both sides of the movable iron core 8 in the axial direction of the shaft 4 (vertical direction in FIG. 1) are provided. A gap for communication is generated. That is, the notch 8c of the movable iron core 8 is a communication part. With this configuration, the gas flows through the gap between the portion where the notch 8c of the movable iron core 8 is provided and the inner peripheral surface of the bottomed cylindrical portion 10, and thus the resistance acting on the movable iron core 8 by air damping. The force can be further reduced to further improve the operation speed of the movable iron core 8, thereby further improving the responsiveness. Here, the depth of the notch 8c is reduced to such an extent that the magnetic force acting on the movable iron core 8 is sufficiently secured.

It is sectional drawing which shows embodiment of this invention. It is a figure which shows the principal part same as the above, (a) is sectional drawing containing a fixed terminal holding member, (b) is a front view. It is a bottom view which shows the elastic cover used for the same as the above. It is sectional drawing which shows the elastic cover used for the same as the above. It is sectional drawing which shows the principal part same as the above. It is a perspective view which shows a movable iron core same as the above. It is sectional drawing which shows a prior art example.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Fixed terminal holding member 2 Fixed terminal 2a Fixed contact 3 Movable contact 3a Movable contact 4 Shaft 5 Movable contact holder 5i Rib 6 Contact pressure spring 8 Movable iron core 10 Bottomed cylinder part 11 1st joining member 12 2nd Joining member 13 Coil 14 Coil frame 15 Yoke 17 Elastic cover 17a Annular piece 17b Groove

Claims (4)

  A fixed terminal provided with a fixed contact, a movable contact provided with a movable contact contacting and separating from the fixed contact, a shaft having one end connected to the movable contact, and a movable iron core connected to the other end of the shaft And an electromagnet that drives the movable iron core in the axial direction of the shaft, and a sealed container that holds the movable contact, the movable iron core, and the shaft in a sealed state while holding the fixed terminal so that the fixed contact is exposed inside And a partition body that pierces the shaft insertion hole through which the shaft is inserted and partitions the space inside the sealed container into a space in which the movable iron core is stored and a space in which the movable contact is stored, and elasticity. An elastic cover that is formed into a cylindrical shape with a material having one end connected to the partition so as to surround the entire circumference of the opening of the shaft insertion hole, and the inner peripheral surface of the other end elastically contacts the entire circumference of the shaft; A space containing a movable iron core Sealed contact device for a vent for the space dynamic contact is accommodated communicates through the shaft insertion hole, characterized in that provided on the elastic cover.   The sealed contact device according to claim 1, wherein the elastic cover includes a buffer portion positioned between the movable contact and the partition.   The sealed contact device according to claim 1, wherein the movable iron core is provided with a communication portion that communicates spaces on both sides of the movable iron core in the axial direction of the shaft.   The movable contact is coupled to the shaft via a holding member that holds a contact pressure spring that applies a contact pressure to the movable contact, and the holding member is in contact with the movable contact and is perpendicular to the axial direction of the shaft. The sealed contact device according to claim 1, further comprising a rotation prohibiting portion that prohibits the rotation of the movable contact inside.

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