JP2009259569A - Current breaking device and its manufacturing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a current breaking device for extinguishing arc discharge surely in a short time, and easily forming a low-melting-point conductor part, as well as its manufacturing method. <P>SOLUTION: The device is made provided with a first electrode 1, a second electrode 2, a third electrode 3 arranged partly superposed with the second electrode, a flexible conductor 5 with flexibility for connecting the first electrode and the second electrode, a low-melting-point conductor 4 fitted at the superposed part of the second electrode and the third electrode to electrically and mechanically connect the second electrode and the third electrode, and a biasing member 6 deforming the flexible conductor by a biasing force in accordance with softening or melting of the low-melting-point conductor to move the second electrode toward a first electrode side. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention cuts off a circuit by detecting heat generated by an overcurrent caused by a circuit short circuit of a device or a failure of a circuit component, etc., and shuts down the circuit by self-heating due to energization. The present invention relates to a current interrupting device and a manufacturing method thereof.

  Conventionally, an example of a current interrupting device that shuts down a circuit by detecting heat generated by an overcurrent caused by a circuit short circuit of a device or a failure of a circuit component and shutting down the circuit, and by self-heating by energization, It has the following configuration. That is, a fuse element that connects between these contact elements is coupled between at least two separated contact elements in the circuit by soldering or the like. At this time, the fuse element is biased in a direction in which the fuse element is separated from the contact element by a spring or the like.

In such a current interrupting device, for example, when the temperature of the fuse element exceeds a predetermined value due to overcurrent, the solder melts. The fuse element is separated from at least one contact element by the biasing force. As a result, the electrical connection between the contact elements is interrupted, and arc discharge that becomes an obstacle when the current is interrupted is avoided.
Japanese Patent Laid-Open No. 11-317144 (FIG. 1)

  In the conventional current interrupting device using the thermal fuse as described above, the electrical contact between the contact element and the fuse element is separated by melting the fuse conductor such as solder. Therefore, when there are two or more locations to be connected by the fuse conductor, there is a time difference until each fuse conductor is softened or melted, and which portion of which fuse conductor is blown out cannot be determined. Therefore, it has been difficult to melt all the fuse conductors at the same time. In addition, as disclosed in Patent Document 1, even when the fuse element is forcibly separated from the contact element by the urging force, a sufficient distance between the fuse element and the contact element should be ensured. It is difficult. Accordingly, there has been a problem that arc discharge generated between the blown fuse conductors cannot be extinguished quickly and arc discharge continues. In addition, in order to manufacture the current interrupt device disclosed in Patent Document 1, the contact element and the fuse element must be joined in a state where the spring is compressed, and it is difficult to form.

The present invention has been made in order to solve the above-described problems, and is capable of interrupting an arc discharge in a shorter period of time and capable of easily forming a low melting point conductor. An object is to provide an apparatus and a method for manufacturing the same.

In order to achieve the above object, the present invention is configured as follows.
That is, the current interrupting device according to the first aspect of the present invention includes a first electrode that forms a part of the current path and is fixed, and a second electrode that forms a part of the current path and is disposed through the gap with the first electrode. An electrode, a third electrode that forms a part of a current path and is arranged and fixed to overlap with the second electrode, and is provided in the gap portion between the first electrode and the second electrode, The first electrode and the second electrode are electrically connected to each other and provided at one place in the overlapping portion of the flexible conductor having flexibility and the second electrode and the third electrode, and the second electrode And a low melting point conductor having a melting point lower than the melting point of the third electrode and electrically connecting the second electrode and the third electrode in a normal state, and one end attached to the second electrode, The second electrode has a biasing force in a direction separating the third electrode from the third electrode, and the low melting point conductor Characterized in that a biasing member is moved by deforming the flexible conductor with the urging force of the second electrode to the first electrode side according to reduction or melting.

  The current interrupting device manufacturing method according to the second aspect of the present invention includes a conductor forming portion penetrating in a thickness direction filled with a low melting point conductor that is softened or melted by heating with an electrode forming a part of a current path. After the two electrodes and the third electrode forming a part of the current path are overlapped by the overlapping portion including the conductor forming portion, the second electrode and the third electrode are connected by the low melting point conductor. A flexible conductor having flexibility by assembling the first electrode forming a part of the current path and the third electrode to the insulator case with a gap between the first electrode and the second electrode. Is provided in the gap portion to electrically connect the first electrode and the second electrode, and after providing the flexible conductor, an urging force in a direction in which the second electrode is separated from the third electrode is applied. And when the low melting point conductor is softened or melted, the biasing force causes the flexibility. To deform the body, characterized in that it comprises to pass over the biasing member for moving the second electrode to the first electrode side between the second electrode and the insulator casing.

  According to the current interrupt device in the first aspect of the present invention, the first electrode, the second electrode connected to the first electrode by the flexible conductor, and the low melting point formed on the overlapped portion overlapping the second electrode. A third electrode connected via the conductor and a biasing member that biases the second electrode are provided. The second electrode and the third electrode are joined by a low melting point conductor provided in one place, and when the low melting point conductor is softened or melted, the second electrode is The flexible conductor is deformed by the urging force and is separated from the electrode, and moves toward the first electrode side, that is, in a direction away from the third electrode. Moreover, since the 2nd electrode is connected with the 1st electrode via the flexible conductor, the moving direction of the 2nd electrode which moves is limited. Therefore, it is possible to secure a large insulation distance between the second electrode and the third electrode in a short time, and it is possible to quickly and surely extinguish arc discharge generated when the conductor is blown.

  Further, by providing a deformable flexible conductor, even when a displacement occurs between the first electrode and the third electrode when the current interrupting device is attached, the above-mentioned displacement is caused by the flexible conductor. Can be absorbed.

  Moreover, according to the manufacturing method of the electric current interruption apparatus in the 2nd aspect of this invention, a biasing member is provided between a 2nd electrode and an insulator case in the last process. Therefore, members other than the urging member are not assembled in a state where the urging force is applied, and the assembly of the current interrupting device is facilitated.

  A current interrupting device as an embodiment of the present invention and a method for manufacturing the current interrupting device will be described below with reference to the drawings. In each figure, the same or similar components are denoted by the same reference numerals. In the illustrations between the drawings, the sizes and scales of the corresponding component parts are independent of each other. For example, the same component parts may be differently shown between the cross-sectional view and the plain view.

Embodiment 1 FIG.
A current interrupting device according to Embodiment 1 will be described with reference to FIGS.
The current interrupt device 101 according to the first embodiment includes, as basic components, a first electrode 1, a second electrode 2, a third electrode 3, and a first electrode 1, each forming a part of a current path. It has a flexible conductor 5 provided between the second electrode 2, a low melting point conductor 4 provided between the second electrode 2 and the third electrode 3, and an urging member 6. These components are attached to the insulator case 7 that forms the casing of the current interrupt device 101. These components will be described in detail below.

  As shown in FIGS. 1 and 3, the insulator case 7 is made of, for example, PBT (polybutylene terephthalate: plastic resin), PPS (polyphenylene sulfide: plastic resin), or the like, and has a box shape with a recess 7 a. In addition, the material of the insulator case 7 is not limited to these, and may be made of other materials as long as it is an insulator.

  In the present embodiment, the first electrode 1, the second electrode 2, and the third electrode 3 are rectangular flat plates as shown in FIG. 2, each made of a copper plate having a thickness of about 1 mm, and in the longitudinal direction 50. In the orthogonal electrode width direction 51, each has the same size. The electrodes 1 to 3 do not necessarily have the same size in the electrode width direction 51. Moreover, the material of each electrode 1-3 is not limited to copper, The metal material which has copper as a main component, For example, a metal material with low electrical resistivity, such as aluminum, can be used.

  The first electrode 1 is disposed along the longitudinal direction 50 at the bottom 7b of the recess 7a of the insulator case 7, and passes through the side wall 7d-1 forming the recess 7a and projects to the outside of the insulator case 7. 1a. In this way, the first electrode 1 is fixed to the bottom 7 b of the insulator case 7.

  The second electrode 2 is disposed along the longitudinal direction 50 at the bottom 7b via the first electrode 1 and the gap 53, and has a length that can be accommodated in the recess 7a. The second electrode 2 is not fixed to the bottom 7b. Further, the second electrode 2 has a protruding portion 2c and a conductor forming portion 2d. The protruding portion 2 c is a portion protruding from the one end 2 a of the second electrode 2, and fixes the one end 6 a of the urging member 6. The conductor forming portion 2 d is a portion that is formed through the second electrode 2 in the thickness direction 52 of each electrode at one location of the second electrode 2 and is filled with the low melting point conductor 4.

  The formation of the conductor forming portion 2d is not limited to the electrode 2, and may be performed on the electrode 3 or both the electrode 2 and the electrode 3. However, since the low melting point conductor 4 must be formed before the electrode 3 is fixed to the insulator case 7, the conductor forming portion 2 d is preferably formed on the electrode 2.

  The third electrode 3 has a part of the second electrode 2 in the thickness direction 52, that is, a region overlapping at least the conductor forming portion 2 d of the second electrode 2, and a bottom portion 7 c of the recess 7 a of the insulator case 7. , Arranged along the longitudinal direction 50. The third electrode 3 has an end portion 3 a that protrudes outside the insulator case 7 through the side wall 7 d-2 that forms the recess 7 a. Therefore, the third electrode 3 is fixed to the bottom portion 7 c of the insulator case 7. A region where the second electrode 2 and the third electrode 3 overlap in the thickness direction 52 is defined as an overlapping portion 54.

The low melting point conductor 4 provided in the conductor forming portion 2d of the second electrode 2 and electrically and mechanically connecting the second electrode 2 and the third electrode 3 has a melting point lower than the melting points of the electrodes 1 to 3. In the present embodiment, for example, Sn-Ag-Cu solder containing Sn as a main component, that is, lead-free solder is used. Yes. Environmental conservation can be achieved by using lead-free solder. In addition, it is the solder which has Ag, Cu, In, Bi, Zn, Ni etc. as a main component, has melting | fusing point lower than melting | fusing point of each electrode 1-3, and is higher than the electrical resistivity of each electrode 1-3. Other metals may be used as long as they have resistivity.
By using the above-described solder material as the low melting point conductor 4, the low melting point conductor 4 can be softened or melted by an overcurrent flowing through the low melting point conductor 4, as will be described later.

FIG. 4 is an enlarged view of the vicinity of the overlapping portion 54 in the current interrupt device 101 according to the first embodiment. Note that the illustration of the insulator case 7 and the like is omitted.
As described above, the second electrode 2 has one conductor forming portion 2d, and the low melting point conductor 4 is filled in the conductor forming portion 2d, so that the second electrode 2 and the third electrode 3 are one It is joined at a point. The planar shape of the conductor forming portion 2d is a circle having a diameter smaller than the size of the second electrode 2 in the width direction 51 in the present embodiment. However, the shape of the conductor forming portion 2d is not limited to a circle, and the low melting point conductor 4 can be formed in a desired shape, and the second electrode 2 and the third electrode 3 can be electrically and mechanically connected. For example, a notch may be used. The shape of the conductor forming portion 2d is preferably a hole shape penetrating the second electrode 2 because the method of filling the molten low melting point conductor 4 into the conductor forming portion 2d and solidifying it is simple.

  In the present embodiment, as shown in FIG. 4, the second electrode 2 and the third electrode 3 are not in direct contact with each other, and an interval 54a of, for example, about 1 mm is formed. In such a state where the gap 54a is formed, by pouring the low melting point conductor 4 into the conductor forming portion 2d, not only the conductor forming portion 2d but also the gap 54a can be filled with the low melting point conductor 4. By comprising in this way, the surface area of the low melting-point conductor 4 which contacts the 2nd electrode 2 and the 3rd electrode 3 can be increased, and when the electric current more than a regulation value flows through each electrode 1-3, it is reliable. In addition, the low melting point conductor 4 can be softened or melted. For this reason, it is preferable to form the gap 54a. Of course, the gap 54a is not formed, and the second electrode 2 and the third electrode 3 are in direct contact with each other, and the conductor forming portion 2d is lowered. The melting point conductor 4 may be filled.

  In addition, it is preferable to provide the resist part 8 in the 2nd electrode 2 or the 3rd electrode 3 according to the said predetermined shape so that the low melting-point conductor 4 may be formed in the clearance gap 54a in a predetermined shape. It is more preferable that the resist portion 8 has a function as a spacer for maintaining a constant distance between the second electrode 2 and the third electrode 3.

  In addition, in the gap 53 between the first electrode 1 and the second electrode 2 arranged as described above, the other end 1b of the first electrode 1 and the other end 2b of the second electrode 2 are electrically connected. A flexible conductor 5 having flexibility is provided for connection. As shown in FIG. 2, the flexible conductor 5 extends along the longitudinal direction 50, and one or more flexible conductors 5 are arranged in the width direction 51. The flexible conductor 5 is formed of a metal material having a melting point higher than that of the low melting point conductor 4. For example, about 1 to 5 Al ribbons or thin Cu plates having a thickness of 200 μm are laminated, Al wires or Cu It is formed of an aggregate of fine metal wires such as wires. Therefore, the flexible conductor 5 can be easily deformed, and can be separated from the third electrode 3 while supporting the second electrode 2 on the first electrode 1 as described later. Therefore, by providing the flexible conductor 5, the second electrode 2 can move so as to rotate around the flexible conductor 5, as shown in FIG. Moreover, the movement direction of the 2nd electrode 2 can be limited by providing the flexible conductor 5. FIG. Further, the flexible conductor 5 is provided in a shape protruding in the thickness direction 52 in the vicinity of the gap 53 so that the deformation is more easily generated. Moreover, when providing the some flexible conductor 5 in the width direction 51, as shown in FIG. 2, you may use the flexible conductor 5 from which size differs, or the flexible conductor 5 from which a kind differs.

  In this embodiment, both ends of the flexible conductor 5 are joined to the first electrode 1 and the second electrode 2 by direct joining such as ultrasonic joining or welding. In particular, since ultrasonic bonding can be performed without requiring heating, it can be said to be a preferable bonding means without affecting the low melting point conductor 4. Note that the joining method is not limited to these, and for example, indirect joining using a brazing material, solder, conductive adhesive, or the like, or mechanical joining such as caulking or screwing may be used. .

  Further, as described above, the second electrode 2 and the third electrode 3 are normally connected by the low melting point conductor 4, and the first electrode 1 and the second electrode 2 are electrically connected by the flexible conductor 5. Thus, the first electrode 1 and the third electrode 3 are electrically connected, and in a normal state, the first electrode 1 and the third electrode 3 are in a conductive state via the low melting point conductor 4.

  The urging member 6 has one end 6 a attached to the protruding portion 2 c of the second electrode 2, formed at a position away from the second electrode 2 in the vicinity of the first electrode 1, and the other end 6 b supported by the support portion. In the present embodiment, the support portion corresponds to the side wall 7 d-1 that forms the recess 7 a of the insulator case 7. In this embodiment, the urging member 6 uses a tension spring and has an urging force in a direction in which the second electrode 2 is separated from the third electrode 3, and is formed of, for example, SUS (stainless steel used: stainless steel). is doing. Further, the direction of separating is specifically a direction in which the one end portion 2a of the second electrode 2 is rotated counterclockwise around the flexible conductor 5 as shown in FIG. . The urging force of the flexible conductor 5 is a force that cuts off the electrical connection between the second electrode 2 and the third electrode 3 and greatly increases the distance between the second electrode 2 and the third electrode 3. For example, a force that simply pulls the second electrode 2 toward the first electrode 1 may be used. In this case, when the second electrode 2 is moved by, for example, a tension spring so as not to prevent the flexible conductor 5 from increasing the distance between the second electrode 2 and the third electrode 3, It is necessary to devise such that the joint with the first electrode 1 is removed.

  As an example, the length of the second electrode 2 is, for example, 8 mm, and an urging member 6 that is extended several millimeters from the normal state is stretched between the protruding portion 2 c and the side wall 7 d-1. It is a tension spring. The urging member 6 is not limited to a tension spring. That is, no force is applied to the flexible conductor 5 before the low melting point conductor 4 is separated, and when the low melting point conductor 4 is separated, the second electrode 2 is rotated counterclockwise in the figure, and the low melting point conductor 4 is separated. After the separation of 4, the second electrode 2, a part of the separated low-melting-point conductor 4, and the biasing member 6 itself are placed in a predetermined position of the recess 7 a of the insulator case 7, and each of the electric circuits including the electrodes 1 to 3 Any means other than a spring may be used as long as it has a function that does not cause the current to be conducted again. For example, rubber having such a function may be used.

The current interrupting device 101 according to the first embodiment having the above-described configuration is manufactured by a process as shown in FIG.
That is, first, in step S61, the second electrode 2 and the third electrode 3 having the conductor forming portion 2d are overlapped and arranged in a straight line along the longitudinal direction 50, and then the low melting point conductor is placed in the conductor forming portion 2d. 4 is filled, and the second electrode 2 and the third electrode 3 are connected. Next, in step S62, the first electrode 1 and the third electrode 3 with the second electrode 2 produced in step S61 are assembled to the insulator case 7. At this time, the first electrode 1 and the second electrode 2 are arranged with a gap 53 in the longitudinal direction 50. In the next step S63, the flexible conductor 5 is provided corresponding to the gap 53 between the first electrode 1 and the second electrode 2, and the first electrode 1 and the second electrode 2 are connected by the flexible conductor 5. To do. Finally, in step S64, the urging member 6 is stretched between the protruding portion 2c of the second electrode 2 and the side wall 7d-1 in the vicinity of the first electrode 1 in the insulator case 7.

  As described above, the assembly is preferably performed in the order from step S61 to step S64. However, if step S64 is the last, the order from step S61 to step S63 may be changed.

The operation of the current interrupt device 101 according to the first embodiment configured as described above will be described.
In the normal configuration shown in FIG. 1, when a current less than a specified value flows through the low melting point conductor 4 and the flexible conductor 5 to the first, second, and third electrodes 1, 2, 3, the low melting point Resistance heat generation in the conductor 4 is low. Therefore, the low melting point conductor 4 is not softened or melted.

  On the other hand, when a current of a specified value or more flows to the first, second, and third electrodes 1, 2, and 3 through the low melting point conductor 4 and the flexible conductor 5, the low melting point is generated by resistance heat generation in the low melting point conductor 4. A local temperature rise occurs in the conductor 4. When the temperature of the low melting point conductor 4 rises to near the melting point of the low melting point conductor 4, the low melting point conductor 4 is softened or melted. Since the urging force of the urging member 6 acts on the second electrode 2, the low melting point conductor 4 softened or melted by the urging force is indicated by reference numerals 4A and 4B in FIG. The second electrode 2 is separated and rotated counterclockwise in the drawing with the flexible conductor 5 as the center of rotation while being supported by the first electrode 1 while the flexible conductor 5 is deformed. Move. By this series of operations, conduction between the second electrode 2 and the third electrode 3 is interrupted.

  At this time, the second electrode 2 separated by the force of the biasing member 6 and the low melting point conductor 4A in the conductor forming portion 2d of the second electrode 2 are pulled by the biasing member 6 as the flexible conductor 5 is deformed. In this state, the insulator case 7 is placed in a predetermined position of the recess 7a, and the circuit is not conducted again. As described above, the direction and distance in which the second electrode 2 separated from the third electrode 3 moves can be limited by the biasing member 6 and the flexible conductor 5. Therefore, the overall size of the current interrupting device 101, and hence the packaging size of the current interrupting device 101 can be reduced.

Conventionally, as described above, in the case where a meltable fuse conductor is provided at a plurality of locations, it has been extremely difficult to divide all of them at the same time. In addition, it is necessary to solidify the fuse conductor in a state where the spring is compressed, and it takes time to manufacture the current interrupting device.
On the other hand, in the current interrupt device 101 of this embodiment, as described above, the second electrode 2 and the third electrode 3 that interrupt the circuit are low melting point conductors filled in the conductor forming portion 2d formed at one place. 4 is joined. Therefore, the part to be softened or melted is one place, and the low melting point conductor 4 can be reliably separated. In addition, after the low melting point conductor 4 is softened or melted, the second electrode 2 is rotated counterclockwise by the urging force of the urging member 6 so that the insulation distance can be secured quickly and largely. Therefore, it is possible to reliably extinguish arc discharge generated when the circuit breaking operation occurs in a shorter time. Therefore, the arc interruption characteristic at a high voltage is improved.

  Furthermore, the low melting point conductor 4 can be formed by filling the low melting point conductor 4 in the conductor forming portion 2d of the second electrode 2 included in the region where the second electrode 2 and the third electrode 3 overlap each other. The biasing member 6 is attached after the connection of the electrodes 1 to 3 is completed. Therefore, the current interrupting device 101 can be easily manufactured as compared with the conventional case, and workability is improved.

In addition, after separation of the low melting point conductor 4, when the distance of rotation or displacement of the second electrode 2 by the biasing member 6 is not sufficient, or when the amount of the low melting point conductor 4 is excessive, or both of these are combined. In such a case, even if the low melting point conductor 4 is separated, the generated arc discharge cannot be extinguished quickly, or the displaced second electrode 2 is moved in the clockwise direction in FIG. It is possible that a situation occurs in which the third electrode 3 comes into contact with the third electrode 3 again, the circuit is turned on again, and the arc discharge is regenerated.
Therefore, in order to avoid such a situation, the extension amount of the urging member 6, the amount and shape of the low melting point conductor 4, the thickness and length of the second electrode 2, and the length of the overlapping portion 54 in the longitudinal direction 50. It is necessary to set so that the conduction between the second electrode 2 and the third electrode 3 is reliably interrupted when the low melting point conductor 4 is softened or melted.

  In the present embodiment, the other end 6 b of the urging member 6 is fixed to the insulator case 7, and the first electrode 1 and the third electrode 3 are fixed to the insulator case 7. Therefore, the urging member 6 is not used as an electric circuit, and the second electrode 2 displaced by the urging force of the urging member 6 can be stored in a predetermined position in the insulator case 7. In addition, the urging force of the urging member 6 can be prevented from acting on the flexible conductor 5 before the low melting point conductor 4 is separated.

  In this embodiment, the insulator case 7 is used. However, in the current interrupt device 101, the insulator case 7 is not an essential component. For example, it can also comprise without using the insulator case 7 like the electric current interruption apparatus 101-1 shown in FIG. In this case, first, before attaching the urging member 6 to the current interrupting device 101-1, the first electrode 1 and the third electrode so that the deformation force does not act on the flexible conductor 5 before the low melting point conductor 4 is divided. It is necessary to fix the positions of the first electrode 1 and the third electrode 3 by attaching 3 to the circuit conductor 13 with a fixture 12 or the like.

  In the configuration that does not use the insulator case 7, it is necessary to form a portion that supports the other end 6 b of the urging member 6. As shown in FIG. 5, when the supporting portion is formed at one end 1a of the first electrode 1, the urging member 6 also constitutes a part of the electric circuit unless the urging member 6 is formed of an insulating material. End up. Therefore, it is preferable to use the insulator case 7 in order to use the current interruption device more safely and reliably.

  Further, for the flexible conductor 5, by using a conductor that can be deformed in various directions, the distance of the gap 53 between the first electrode 1 and the second electrode 2 is secured, for example, by about 1 mm. Even when a force is unexpectedly generated in the first electrode 1 and the third electrode 3 according to the attachment of the electrode 1 and the third electrode 3 to the insulator case 7, the force is absorbed by the flexible conductor 5. It becomes possible.

Embodiment 2. FIG.
Next, a current interrupting device according to Embodiment 2 of the present invention will be described below with reference to FIGS.
The major difference between the current interrupt device 102 in the second embodiment and the current interrupt device 101 described above with reference to FIG. 1 is that the heater 9 corresponds to the overlapping portion 54 of the second electrode 2 and the third electrode 3. This is the point. Below, only the change part accompanying the said difference is demonstrated, and description here is abbreviate | omitted about the same component as the above-mentioned electric current interruption apparatus 101. FIG.

In the third electrode 3-1 in the second embodiment, which corresponds to the third electrode 3 described in the first embodiment, the third electrode 3-1 corresponding to the conductor forming portion 2 d of the second electrode 2. Is formed in the thickness direction 52 to form a conductor forming portion 3d. In addition, the description regarding the conductor formation part 3d can apply the description mentioned above about the conductor formation part 2d as it is, and description here is abbreviate | omitted.
In addition, in the insulator case 7-1 according to the second embodiment, which corresponds to the insulator case 7 described in the first embodiment, the heater 9 is embedded corresponding to the overlapping portion 54. Furthermore, the insulator case 7-1 has a recess that forms a gap 7e between the heater 9 and the third electrode 3-1. The gap 7e is filled with the low melting point conductor 4 through the conductor forming portion 2d and the conductor forming portion 3d. In order to define the filling range of the low melting point conductor 4, it is preferable to form a resist portion 8 in the gap 7e.
Other components are the same as those of the current interrupt device 101 described above.

The above differences will be described in detail.
The heater 9 corresponds to an example of a heating unit that actively heats and softens or melts the low-melting-point conductor 4, and is configured by a ceramic heater in this embodiment. The heater 9 includes a sheath portion 9A, a heating element 10 mounted on the lower surface thereof, and a lead wire 11 that is electrically connected to the heating element 10 and supplies power. The material of the sheath portion 9A may be an insulator, but for example, alumina or the like is suitable because it has a high melting point and high insulation. In the second embodiment, alumina having a thickness of 1 mm is used. The heater 9 is not electrically connected to the circuit to which the current interrupt device 102 is connected, and does not hinder the operation of the current interrupt device 102. The heater 9 has only to have such a function, and is not limited to a ceramic heater.

In this embodiment, the sheath portion 9 </ b> A has a flat plate shape, and has a size equal to or smaller than the width dimension of the third electrode 3-1 in the width direction 51 as shown in FIG. 8. It has a length approximately equal to the length.
The heating element 10 has a width dimension equal to or less than the width dimension of the sheath portion 9A in the width direction 51 and a length equal to or less than the length dimension of the sheath portion 9A in the longitudinal direction 50, but is preferably as wide as possible. However, the width of the heating element 10 preferably does not exceed the width of the third electrode 3-1, and preferably exceeds the width of the low melting point conductor 4. That is, it is preferable that the heating element 10 is disposed corresponding to the region of the third electrode 3-1 and the low melting point conductor 4 that are in contact with the sheath portion 9 </ b> A of the ceramic heater 9.

  Thus, by arranging the sheath portion 9A of the ceramic heater 9 and the heating element 10, the heat generated from the ceramic heater 9 is efficiently transmitted to the low melting point conductor 4, and the temperature rise of the ceramic heater 9 is suppressed. However, the low melting point conductor 4 can be efficiently heated. Of course, the configuration is not limited to the configuration of the present embodiment, and the width dimension of the sheath portion 9A may exceed the width dimension of the third electrode 3-1, and the width dimension of the heating element 10 is the third dimension. You may make it exceed the electrode 3-1.

  Further, in the above-described current interrupting device 102, as shown in FIG. 6, the conductor forming portion 2d of the second electrode 2 and the conductor forming portion 3d of the third electrode 3-1 formed in the overlapping portion 54 have the same shape. It is the same size. However, the present invention is not limited to this, and at least one of the shape and size of the conductor forming portion 2d of the second electrode 2 and the conductor forming portion 3d of the third electrode 3-1 may be different from each other. FIG. 9 is an enlarged view of the overlapping portion 54 in the current interrupt device 102-1 which is a modification of the current interrupt device 102 according to the second embodiment. In FIG. 9, the conductor forming portion 3d of the third electrode 3-1. The case where the size of the conductor formation part 2d of the 2nd electrode 2 was enlarged compared with is shown.

  The low melting point conductor 4 is filled in the conductor forming portion 2d of the second electrode 2, the conductor forming portion 3d of the third electrode 3-1, and the gap 7e between the third electrode 3-1 and the sheath portion 9A. As a result, the second electrode 2, the third electrode 3-1, and the ceramic heater 9 are coupled. The planar shapes of the conductor forming portion 2d and the conductor forming portion 3d are smaller than the width dimensions of the second electrode 2 and the third electrode 3-1, respectively, for example, circular, but the low melting point conductor 4 is the target shape. Any shape can be used as long as the second electrode 3 and the third electrode 3-1 can be electrically and mechanically connected, and can be in contact with or mechanically connected to the ceramic heater 9.

  In the present embodiment, the gap 7e has a size of about 0.5 mm in the thickness direction 52, for example. By filling the gap 7e with the low melting point conductor 4, the heat generated from the ceramic heater 9 can be transmitted to the low melting point conductor 4 more efficiently. In this case, it is preferable to provide the resist portion 8 on the third electrode 3-1 or the ceramic heater 9 in order to form the low melting point conductor 4 in a desired range in the gap 7e.

  In order to efficiently transfer the heat generated from the ceramic heater 9 to the low melting point conductor 4 and not to move the ceramic heater 9 when the current interrupting device 102 operates, the above-described FIGS. It is preferable to adopt the structure shown. However, the ceramic heater 9 may be directly contacted or mechanically connected to the third electrode 3-1, without forming the gap 7e, or the conductor forming portion 3d may be formed on the third electrode 3-1. That is, the third electrode 3-1 may not be filled with the low melting point conductor 4, and the ceramic heater 9 may indirectly heat the conductor forming portion 2 d of the second electrode 2. Further, the ceramic heater 9 is connected to the second electrode so that the ceramic heater 9 can directly heat the low melting point conductor 4 of the second electrode 2 while the second electrode 2 and the third electrode 3-1 are electrically connected. You may arrange | position in contact with 2.

  The lead wire 11 is electrically connected to the heating element 10 so as not to interfere with the operation of the current interrupting devices 102 and 102-1, and not to be in electrical contact with the current interrupting devices 102 and 102-1. That is, the lead wire 11 is preferably electrically insulated by being covered with an insulating film or the like except for the connection portion with the heating element 10.

  The manufacturing method of the current interrupting devices 102 and 102-1 according to the second embodiment configured as described above is basically the same as the manufacturing method of the current interrupting device 101 shown in FIG. 11, and step S61, step S62, Or between step S62 and step S63 can be performed by adding a step of disposing the ceramic heater 9 below the low melting point conductor 4.

The operation of the current interrupting devices 102 and 102-1 according to the second embodiment configured as described above will be described.
The basic operation of the current interrupting devices 102 and 102-1 is the same as the operation of the current interrupting device 101 of the first embodiment described above, and an overcurrent exceeding a specified value is caused by the first electrode 1, the second electrode 2, and When flowing through the third electrode 3-1, the low melting point conductor 4 is softened or melted, and the second electrode 2 is separated from the third electrode 3-1, by the biasing force of the biasing member 6. The conduction between the three electrodes 3-1 is interrupted.
Therefore, the current interrupting devices 102 and 102-1 according to the second embodiment can also be achieved with respect to the effect exhibited by the current interrupting device 101 described above.

  Furthermore, in the current interrupting devices 102 and 102-1 of this embodiment, the heating element 10 of the ceramic heater 9 is heated by energization from the lead wire 11 independently of the current interrupting devices 102 and 102-1, and the low melting point conductor 4 can be preheated. Therefore, by heating the ceramic heater 9 in advance, when a current exceeding a specified value flows through the first electrode 1, the second electrode 2, and the third electrode 3-1, that is, when the current flows through the low melting point conductor 4. The low melting point conductor 4 can be made softer or more easily melted than usual. Therefore, it is possible to interrupt the conduction between the first electrode 1 and the third electrode 3-1 more quickly than the current interrupt device 101 in the first embodiment. Therefore, the arc discharge generated when the circuit breaking operation occurs can be surely extinguished in a shorter time. Thus, the current interruption device according to the second embodiment has improved arc interruption characteristics at a high voltage.

  Furthermore, in the second embodiment, the low melting point conductor 4 can be softened or melted by the ceramic heater 9 regardless of the current flowing through the low melting point conductor 4. Further, by adjusting the amount of heat generated by the ceramic heater 9, it is possible to obtain an effect that the time until the low melting point conductor 4 is separated can be arbitrarily set to some extent.

  Further, as in the case of the current interrupt device 101 in the first embodiment, also in the second embodiment, the attaching operation of the urging member 6 is performed after all the electrodes 1 to 3 are connected. Can be easily assembled, and the workability during assembly is also improved.

2. State of implementation
Next, a current interrupting device according to Embodiment 3 of the present invention will be described with reference to FIG.
In the current interrupt device 102 according to the second embodiment described above, as shown in FIG. 8, a thin metal plate such as an Al ribbon or a Cu plate is used as the flexible conductor 5. On the other hand, the current interrupt device 103 according to the third embodiment is different in that a metal wire 14 is used as the flexible conductor 5. The other components of the current interrupt device 103 are the same as the configuration of the current interrupt device 102.

In this embodiment, for example, an Al wire having a diameter of 400 μm is used as the metal wire 14, but other materials may be used as long as the conductor has a melting point higher than that of the low melting point conductor 4. For example, Cu is suitable because it has a high melting point, low electrical resistivity, and easy bonding. Further, the cross-sectional shape of the metal wire 14 may be an ellipse, a quadrangle, a triangle, etc. in addition to a circle. Further, when the metal wire 14 is used, there is an advantage that the number and shape of the metal wires 14 used according to the current value to be handled can be freely changed as compared with the case where a metal plate is used. In addition, there is also an advantage that the degree of freedom of deformation is high, and the arrangement can be provided so as to be stacked one above the other.
Note that the operation and manufacturing method of the current interrupt device 103 according to the third embodiment are the same as those of the current interrupt device 101 according to the first or second embodiment, and the description thereof is omitted.

  In addition, it is also possible to take the structure which combined each Embodiment 1-3 mentioned above suitably.

It is sectional drawing which shows the structure of the electric current interruption apparatus by Embodiment 1 of this invention. It is a top view which shows the structure of the electric current interruption apparatus shown in FIG. FIG. 2 is a cross-sectional view showing a state when a low melting point conductor is blown in the current interrupting device shown in FIG. 1. It is sectional drawing to which the low melting-point conductor part in the electric current interruption apparatus shown in FIG. 1 was expanded. It is sectional drawing which shows the structure of the modification of the electric current interruption apparatus shown in FIG. It is sectional drawing which shows the structure of the electric current interruption apparatus by Embodiment 2 of this invention. FIG. 7 is a cross-sectional view showing a state where a low melting point conductor is blown in the current interrupt device shown in FIG. 6. It is a top view which shows the structure of the electric current interruption apparatus by Embodiment 2 of this invention. It is sectional drawing which shows the structure in the modification of the low melting-point conductor part in the electric current interruption apparatus shown in FIG. It is a top view which shows the structure of the electric current interruption apparatus by Embodiment 3 of this invention. It is a flowchart explaining the outline of the manufacturing method of the electric current interruption apparatus shown in FIG.

Explanation of symbols

1 first electrode, 2 second electrode, 3rd electrode, 4 low melting point conductor, 5 flexible conductor,
6 biasing member, 7 insulator case, 9 ceramic heater, 9A sheath part,
10 heating element, 14 metal wire, 54 overlapping part,
101-103 Current interrupting device.

Claims (9)

A first electrode fixed as a part of a current path;
A second electrode that forms part of the current path and is disposed with a gap between the first electrode,
A third electrode that forms a part of the current path and is arranged and fixed to overlap with the second electrode;
A flexible conductor provided in the gap portion between the first electrode and the second electrode, electrically connecting the first electrode and the second electrode, and having flexibility;
The second electrode and the third electrode are provided at one place in the overlapping portion of the second electrode and the third electrode, and have a melting point lower than the melting points of the second electrode and the third electrode, and normally the second electrode and the third electrode, A low melting conductor that electrically and mechanically connects,
One end is attached to the second electrode and has an urging force in a direction to separate the second electrode from the third electrode, and the flexible conductor is urged by the urging force according to softening or melting of the low melting point conductor. And a biasing member that moves the second electrode toward the first electrode,
A current interrupting device comprising:   2. The current interrupting device according to claim 1, wherein the second electrode has a conductor forming portion that is formed through the second electrode at one position in the overlapping portion and is filled with the low melting point conductor.   3. The current interrupting device according to claim 1, further comprising a heater arranged corresponding to the low melting point conductor in a thickness direction of the third electrode and forcibly softening or melting the low melting point conductor by heating. . The first electrode, the second electrode, and the third electrode are plate-shaped,
The heater includes a sheath portion made of a flat plate-like insulator having a width smaller than the width of each electrode, and a heating element having a width smaller than the width of each electrode or the low melting point conductor attached to one surface of the sheath portion. The electric current interruption apparatus of Claim 3 which has.   5. The current interrupting device according to claim 3, wherein the third electrode has a conductor forming portion that is formed through the third electrode at one position in the overlapping portion and is filled with the low melting point conductor.   A support portion that is formed of an insulating member, fixes the first electrode and the third electrode, and is formed at a position near the first electrode and away from the second electrode, and supports the other end of the biasing member. And further comprising an insulator case that accommodates the second electrode moved to the first electrode side by the biasing member in a state of disconnection from the third electrode. The current interrupting device according to any one of the above.   The current interrupt device according to any one of claims 1 to 6, wherein the flexible conductor is formed of a thin plate metal or a laminate thereof, or a thin metal or an assembly thereof. A second electrode having a conductor forming portion penetrating in a thickness direction filled with a low-melting-point conductor that is softened or melted by heating, and a third electrode that forms a part of the current path. After overlapping at the overlapping portion including the conductor forming portion, connecting the second electrode and the third electrode with the low melting point conductor,
Assembling the first electrode forming a part of the current path and the third electrode to the insulator case with a gap between the first electrode and the second electrode,
Providing a flexible conductor in the gap portion to electrically connect the first electrode and the second electrode;
After providing the flexible conductor, the flexible conductor has an urging force in a direction to separate the second electrode from the third electrode. When the low melting point conductor is softened or melted, the flexible conductor is deformed by the urging force. An urging member that moves the second electrode toward the first electrode is bridged between the second electrode and the insulator case.
The manufacturing method of the electric current interruption apparatus characterized by the above-mentioned.   After the second electrode and the third electrode are connected by the low melting point conductor, and before the first electrode and the second electrode are electrically connected by the flexible conductor, the third electrode The method for manufacturing a current interrupting device according to claim 8, further comprising providing a heater for forcibly softening or melting the low-melting-point conductor below the conductor forming portion in the thickness direction.

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