WO2017130306A1 - Chip fuse and chip fuse production method - Google Patents

Abstract

A chip fuse (1) is provided with: a casing (5) which includes an insulating resin as a base material and which forms a sealed space (6); a fusible body (30) which is provided in the sealed space (6) in a state of being hanged and supported in the air and which includes nickel as the base material; and a pair of terminals (40, 50) which have a structure that is integrated with the casing (5) so that a portion of the terminals is exposed from the casing (5), and which are electrically connected to both end sections of the fusible body (30).

Description

Chip fuse and manufacturing method of chip fuse

The present invention relates to a chip fuse having a fusible body that is supported aerial between terminals, and a method for manufacturing the chip fuse.

In electronic equipment, fuses are used to prevent circuit breakdown due to inflow of overcurrent caused by failure. The fuse has a fusible body, and when an abnormal current flows through the circuit on which the fuse is mounted, the fusible body melts and interrupts the current to prevent circuit destruction.

In the fuse of Patent Document 1 below, a fusible body that is supported aerial inside the case is fixed to terminals provided at both ends of the case with solder. Here, the solder also has a function of closing the opening of the terminal for inserting the fusible body.

JP 2002-50274 A

In general fuses, it is desirable to increase the airtightness of the case that contains the fusible body, because the spark generated when the fusible body melts may cause an explosion if it touches the outside air. In addition, it is known that the current interruption performance by the fuse is greatly dependent on the pressure of the atmosphere (gas) surrounding the fusible body when the fuse operates, and in order to increase the pressure, increase the airtightness of the case is important. However, when the fusible body is fixed to the terminal with solder as in Patent Document 1, for example, the solder that closes the opening of the terminal melts when the fusible body generates heat, and the airtightness of the case may be reduced. is there.

In addition, in the case of the fuse of Patent Document 1, when assembling the fuse, it is necessary to fix the fusible body to the terminal with solder while the linear fusible body is inserted into the opening of the terminal and held at a predetermined position. There is. However, since such a series of assembling operations requires skill, if an ordinary worker performs the assembling operations, a great amount of time is required for the operations.

Therefore, the present invention has been made in view of these points, and an object thereof is to improve the airtightness of the fuse case and improve the assemblability.

In the first aspect of the present invention, the housing includes an insulating resin as a base material and forms a sealed space, and is provided in an aerial support state in the sealed space, and the base material may include nickel. A chip fuse comprising: a solution; and a pair of terminals that are integrated with the housing such that a part of the solution is exposed from the housing and electrically connected to both ends of the fusible body. provide.

The housing includes a case member integrated with the terminal, and a lid member joined to the opposing case member and forming the sealed space with the case member. It is good as well.

The case member has a case-side joining surface formed in an annular shape along an outer edge, and the lid member is formed in an annular shape along the outer edge and joined to the case-side joining surface. It is good also as having a surface.

In addition, one of the case member and the lid member has a convex portion, and the other of the case member and the lid member has a concave portion that is fitted to the convex portion, and the top surface of the convex portion. The bottom surface of the recess may be joined.

Further, the case member and the lid member may be made of the same thermoplastic resin.

Further, the terminal may have a holding portion that is provided in the sealed space and holds an end portion in the longitudinal direction of the fusible body.

The sandwiching portion includes a support portion that supports the end portion of the fusible body, and a pressing portion that faces the support portion and presses the end portion supported by the support portion. In the longitudinal direction, the support portion may be provided to the end side of the pressing portion.

Further, the upper surface of the support portion may be located at the same height as the upper surface of the case member.

Further, the casing may have a groove portion that is formed between the fusing space in which the fusible body is melted in the sealed space and the clamping portion, and through which the fusible body passes.

The terminal includes a terminal portion that is exposed to the outside in a state of being integrated with the sandwiching portion, a through portion that penetrates the wall of the housing and connects the sandwiching portion and the terminal portion, It is good also as having.

Further, the terminal may be made of a metal plate, and the penetrating portion may have a shape obtained by bending the metal plate a plurality of times.

Further, the terminal portion may include a side terminal portion located on a side surface of the case member, and an outer surface of the side terminal portion may be located at the same position as the side surface of the case member.

The terminal portion includes a bottom surface terminal portion positioned on the bottom surface of the case member, and the bottom surface of the bottom surface terminal portion protrudes smaller than a thickness of the bottom surface terminal portion with respect to the bottom surface of the case member. It is good as well.

Further, the fusible body has a fusible body plating layer on which metal plating is applied, the terminal has a terminal plating layer on which a metal plating is applied on the surface of the metal plate, and the terminal plating layer is It is good also as joining and electrically connecting with the said soluble body plating layer.

In the second aspect of the present invention, a case assembly in which a case member including an insulating resin as a base material and a pair of metal terminals are integrally formed, and a part of the terminals are exposed from the case member. A step of producing a solid, a step of disposing a soluble body containing at least nickel on the case member of the case assembly, and fixing the soluble body to the terminal; and a lid member containing an insulating resin as a base material; There is provided a method for manufacturing a chip fuse, comprising: joining the case member of the case assembly to seal the fusible body in a sealed space.

Further, the step of manufacturing the case assembly includes processing a long first metal plate and forming a plurality of the terminals at predetermined intervals on the first metal plate, and each of the plurality of terminals. And injecting an insulating resin into the first metal plate so as to be integrated with the first metal plate, and molding the plurality of case members supported by the first metal plate at the predetermined interval. It is good as well.

Further, in the manufacturing method of the chip fuse, an insulating resin is injection-molded with respect to the long second metal plate, and the plurality of lid members supported by the second metal plate at the predetermined interval are formed. Joining the case member of the case assembly supported by the first metal plate and the lid member supported by the second metal plate, the first metal plate and the second metal plate. And a step of producing a fuse assembly supported on the metal plate.

The method for manufacturing a chip fuse includes the steps of separating the fuse assembly from the first metal plate, and measuring a resistance value between the terminals of the fuse assembly separated from the first metal plate; And determining whether to separate the fuse assembly from the second metal plate based on the measurement result of the resistance value.

According to the present invention, it is possible to improve the hermeticity of the fuse case and improve the assemblability.

It is a schematic diagram which shows the structure of the fuse 900 which concerns on a comparative example. 1 is a perspective view showing a schematic configuration of a chip fuse 1 according to an embodiment of the present invention. 2 is a perspective view showing a schematic configuration of the chip fuse 1 in a state where a lid member 20 and a case member 10 are separated. FIG. 1 is a front view of a chip fuse 1. 2 is a side view of the chip fuse 1. FIG. FIG. 3B is a cross-sectional view taken along line AA in FIG. 3B. FIG. 5 is a sectional view taken along line BB in FIG. 4. It is a top view of case member 10 FIG. 7 is a cross-sectional view taken along the line CC of FIG. 3 is a plan view of a lid member 20. FIG. FIG. 9 is a sectional view taken along the line DD of FIG. 4 is a flowchart showing manufacturing steps of the chip fuse 1. It is a top view of the metal plate 600 for cases where the terminals 40 and 50 are shape | molded. It is the figure which looked at the metal plate 600 for cases shown in FIG. 11 from the front side. It is a perspective view which shows the terminals 40 and 50 shape | molded by the metal plate 600 for cases. It is a top view of the metal plate 600 for cases in which the case assembly 650 is produced. It is the figure which looked at the metal plate 600 for cases shown in FIG. 14 from the front side. FIG. 10 is a plan view showing a state in which a long elongate fusible body 660 is disposed on a plurality of case assemblies 650. It is a longitudinal cross-sectional view of the case assembly 650 of FIG. FIG. 18 is a cross-sectional view taken along line EE in FIG. 17. It is a top view of the metal plate 700 for lid | covers with which the lid member 20 is shape | molded. It is the figure which looked at the metal plate 700 for lids shown in FIG. 19 from the front side. A longitudinal sectional view of a fuse assembly 800 in which the lid member 20 is joined to the case member 10 of the case assembly 650 is shown. It is a figure which shows the state by which the fuse assembly 850 is supported by the metal plate 600 for cases, and the metal plate 700 for lid | covers. FIG. 23 is a cross-sectional view taken along line FF in FIG. 22.

Below, it demonstrates in the order shown below.
1. Comparative Example 1-1. Configuration of fuse according to comparative example 1-2. 1. Problems with fuses according to comparative examples Embodiment 2-1. Configuration of chip fuse 2-2. Characteristics of chip fuse 2-3. Manufacturing method of chip fuse 2-4. Effects of this manufacturing method 2-5. Modified example

<1. Comparative Example>
Before describing the fuse according to the present invention, a fuse according to a comparative example will be described. In the following, after describing the configuration of the fuse according to the comparative example, problems that occur in the fuse according to the comparative example will be described.

(1-1. Configuration of fuse according to comparative example)
FIG. 1 is a schematic diagram illustrating a configuration of a fuse 900 according to a comparative example. As shown in FIG. 1, the fuse 900 includes a tube 901, a fusible body 902, and a pair of terminals 903 and 904. The fuse 900 is a tubular fuse and supports the fusible body 902 in an aerial manner.

The tube 901 is made of alumina (aluminum oxide) and has a cylindrical shape. The fusible body 902 is a linear fuse element, and is supported in an aerial manner in the tube 901. The fusible body 902 is made of copper here.

Terminals 903 and 904 are connected to the longitudinal ends of the fusible body 902, respectively. The terminals 903 and 904 are made of brass and have a cylindrical shape. The terminals 903 and 904 are bonded to the outer peripheral surface of the tube 901 with an adhesive 920.

The terminals 903 and 904 are provided with openings 903a and 904a, and the end of the fusible body 902 is located in a state of being inserted through the openings 903a and 904a. The end of the fusible body 902 is fixed to the terminals 903 and 904 with solder 910. Note that the solder 910 is provided so as to close the openings 903a and 904a. That is, the solder 910 has a function of fixing the fusible body 902 to the terminals 903 and 904 and a function of sealing the openings 903a and 904a.

The fuse 900 is assembled as follows.
First, terminals 903 and 904 are bonded to both ends of the tube 901 with an adhesive 920 to manufacture a tube assembly. Next, the fusible body 902 is inserted from the opening 903 a of the terminal 903 or the opening 904 a of the terminal 904, and the end of the fusible body 902 is held at a position to be fixed to the terminals 903 and 904. Next, the openings 903a and 904a are filled with solder, and the ends of the fusible body 902 are fixed to the terminals 903 and 904. At this time, the inside of the tube 901 is hermetically sealed by filling solder so as to seal the openings 903a and 904a.

(1-2. Problems with fuses according to comparative examples)
The fuse 900 according to the comparative example has the following problems with respect to hermeticity and assemblability.

(Problems in airtightness)
In the fuse 900, the solder 910 that fixes the fusible body 902 to the terminals 903 and 904 may melt and the airtightness may be reduced.
Specifically, the heat of the fusible body 902 generated during the operation of the fuse 900 is transmitted to the solder 910 connecting the end of the fusible body 902 and the terminals 903 and 904, so that the solder 910 is melted or melted. Soften. In such a case, the solder 910 cannot withstand the pressure in the tube 901 and is ejected from the openings 903a and 904a of the terminals 903 and 904, and the airtightness of the tube 901 is reduced. As a result, the pressure in the tube 901 decreases, and the circuit current interruption due to the melting of the fuse 900 cannot be completed within a predetermined time. As a result, there is a risk that a spark generated when the fusible body 902 is melted may touch the outside air and lead to an explosion.

In particular, with the recent miniaturization of the fuse 900, the length between the terminals 903 and 904 of the fusible body 902 (the length Le shown in FIG. 1) has been reduced. In such a case, when the fuse 900 is operated, the amount of heat transferred from the heat generating fusible body 902 to the solder 910 increases, so that the solder 910 is easily melted and the airtightness of the tube 901 is likely to be lowered.

Further, in the fuse 900, the airtightness of the bonded portion where the terminals 903 and 904 and the tube 901 are bonded with the adhesive 920 may be lowered.
Here, it is assumed that the fuse 900 has been used for a long time. In the fuse 900 that has been used for a long period of time, a phenomenon occurs in which the terminals 903 and 904 are displaced in the direction in which they are removed from the tube 901 during the operation of the fuse 900, and the airtightness is lowered. Even in such a case, the pressure in the tube 901 decreases, and the interruption of the circuit current due to the melting of the fuse 900 cannot be completed within a predetermined time.

Here, the reason why the terminals 903 and 904 are shifted in the direction of coming out of the tube 901 will be described.
In the fuse 900, the linear expansion coefficients of the tube 901, the terminals 903 and 904, and the adhesive 920 are different. Specifically, the linear expansion coefficient of the alumina tube 901 is about 8.5 × 10 ⁻⁶ (/ K), and the linear expansion coefficients of the brass terminals 903 and 904 are about 19 × 10 ^−6. (/ K), and the linear expansion coefficient of the adhesive 920 is about 30 × 10 ⁻⁶ (/ K). For this reason, when a temperature change occurs, the stress caused by the difference in coefficient of linear expansion between the tube 901, the terminals 903 and 904, and the adhesive 920 causes the adhesive interface between the adhesive 920 and the tube 901, the adhesive 920 and the terminal 903, Occurs at the adhesive interface with 904. When the use period of the fuse 900 becomes long and the temperature change is repeated, the stress repeatedly acts on the adhesive interface, so that the adhesive force of the adhesive 920 is reduced. As a result, the terminals 903 and 904 cannot withstand the increase in internal pressure of the tube 901 that occurs during the operation of the fuse 900, and shift in the direction in which the terminals 903 and 904 come out of the tube 901.

When the fuse 900 is used for a long period of time, a high temperature atmosphere (gas) in the tube 901 is ejected from the adhesive interface between the adhesive 920 and the tube 901 or the adhesive interface between the adhesive 920 and the terminals 903 and 904. Has been confirmed to occur.

(Problems in assembly)
Next, three problems in assembly of the fuse 900 will be described.

First, in the fuse 900, since it is difficult to bond the terminals 903 and 904 to both ends of the tube 901 with the adhesive 920 so as to ensure the airtightness of the tube 901, the yield is poor. Specifically, after the adhesive 920 is applied to the end of the cylindrical tube 901 in advance, the adhesive 920 is placed between the tube 901 and the terminals 903 and 904 by covering the tube 901 with the terminals 903 and 904. Is supposed to be filled. However, it is extremely difficult to fill the adhesive without any gap between the tube 901 and the terminals 903 and 904, and in particular, the yield is poor in terms of maintaining the sealing property of the tube 901.

Second, it is difficult to insert the fusible body 902 into the tube 901 from the opening 903a of the terminal 903 or the opening 904a of the terminal 904 and hold the end of the fusible body 902 at a position to fix the terminal to the terminals 903 and 904. . That is, since it is necessary to load the fusible body 902 into the closed space of the tube 901 from the narrow openings 903a and 904a, the workability is poor and the work takes a long time. Further, when the fusible body 902 is thin, the fusible body 902 is easily bent due to the low rigidity of the fusible body 902, and the workability is further deteriorated.

As a third point, the work of sealing the openings 903a and 904a with the solder 910 while fixing the ends of the fusible body 902 to the terminals 903 and 904 with the solder 910 requires skill. That is, since it is necessary to simultaneously perform the work of fixing the fusible body 902 to the terminals 903 and 904 and the work of sealing the openings 903a and 904a with the solder 910, a normal worker who is not skilled in the work performs the work. It will take a lot of time.

<2. This embodiment>
(2-1. Configuration of chip fuse)
The configuration of the chip fuse 1 according to an embodiment of the present invention will be described with reference to FIGS. 2A, 2B, 3A, 3B, and 4 to 9. FIG.

FIG. 2A is a perspective view showing a schematic configuration of the chip fuse 1 according to the embodiment. FIG. 2B is a perspective view showing a schematic configuration of the chip fuse 1 in a state where the lid member 20 and the case member 10 are separated. FIG. 3A is a front view of the chip fuse 1. FIG. 3B is a side view of the chip fuse 1. 4 is a cross-sectional view taken along line AA in FIG. 3B. 5 is a cross-sectional view taken along the line BB of FIG. FIG. 6 is a plan view of the case member 10. 7 is a cross-sectional view taken along the line CC of FIG. FIG. 8 is a plan view of the lid member 20. 9 is a cross-sectional view taken along the line DD of FIG.

The chip fuse 1 is surface-mounted on a circuit board or the like of an electronic device and is blown when an abnormal current flows through the circuit. The chip fuse 1 is a small fuse. Here, the length L1 (FIG. 2A) of the chip fuse 1 is about 2.5 (mm), and the width L2 (FIG. 2A) is about 1.5 (mm). The thickness L3 (FIG. 2A) is about 1.3 (mm).

As shown in FIG. 2A, the chip fuse 1 has a housing 5 whose outer shape is box-shaped. The housing 5 is made of an insulating resin, specifically, a liquid crystal polymer. The liquid crystal polymer has excellent heat resistance and high fluidity during injection molding. A sealed space (a sealed space 6 shown in FIG. 4) is formed in the housing 5. In addition, the housing | casing 5 is not limited to the above, You may contain another material in the insulating resin which is a base material.

The chip fuse 1 includes a case member 10, a lid member 20, a fusible body 30, and a pair of terminals 40 and 50 as shown in FIG. 2B and the like. The chip fuse 1 is electrically connected to the circuit board through terminals 40 and 50, and current is supplied from the circuit board to the fusible body 30 through the terminals 40 and 50. In the present embodiment, the case member 10 and the lid member 20 constitute the housing 5.

(Case member 10)
The case member 10 is a base portion of the housing 5 and houses the fusible body 30 and the terminals 40 and 50 as shown in FIG. 2B. The case member 10 is made of a liquid crystal polymer that is a thermoplastic resin. The case member 10 has a rectangular parallelepiped shape as shown in FIG. 2B. The case member 10 includes a fusible member accommodating portion 11, a terminal accommodating portion 12, a case side joining surface 13, a fitting convex portion 14, and a positioning groove portion 15.

The fusible body accommodating portion 11 is a concave portion that accommodates the fusible body 30. As shown in FIG. 2B, the fusible body accommodating portion 11 is surrounded by a wall 11a. The fusible body accommodating portion 11 is provided at the center of the case member 10. The soluble body accommodating part 11 is also a fusing space in which the fusible body 30 is fused.

The terminal accommodating portion 12 is a recess that accommodates the pair of terminals 40 and 50. The terminal accommodating part 12 is provided on both sides of the fusible substance accommodating part 11. The terminal accommodating portion 12 is in close contact with the terminals 40 and 50. For this reason, no gap is formed between the terminal accommodating portion 12 and the terminals 40 and 50.

The case side joining surface 13 is joined to the lid side joining surface 22 of the lid member 20, as shown in FIG. As shown in FIG. 2B, the case side joining surface 13 is formed in an annular shape along the outer edge of the upper surface of the case member 10 so as to surround the fusible body housing portion 11 and the terminal housing portion 12. The case side joining surface 13 is a surface having high flatness. In addition, the upper surface of the wall 11a of the fusible body housing portion 11 protrudes from the case side joining surface 13.

The fitting convex part 14 is fitting with the fitting concave part 23 of the lid member 20 as shown in FIG. 3A. The fitting convex part 14 protrudes from the case side joining surface 13. 2B, the fitting convex part 14 is provided in the center of the longitudinal direction (X direction) of the case member 10, and the edge of the both sides of the width direction (Y direction).

The positioning groove part 15 is a groove part formed along the longitudinal direction on the wall 11a of the fusible body accommodating part 11, as shown in FIG. 2B. The positioning groove 15 has a function for positioning when the fusible body 30 is accommodated in the case member 10. The positioning groove portion 15 is provided between the fusible body housing portion 11 and the terminal housing portion 12, and both end portions of the fusible body 30 pass through the positioning groove portion 15.

(Cover member 20)
The lid member 20 is a lid portion of the housing 5 and has a rectangular shape similar to the case member 10 as shown in FIG. 2B. The lid member 20 is made of a liquid crystal polymer that is the same thermoplastic resin as the case member 10. The lid member 20 is joined to the opposing case member 10 and forms a sealed space 6 with the case member 10 as shown in FIG. As shown in FIG. 8, the lid member 20 includes a central recess 21, a lid-side joining surface 22, and a fitting recess 23.

The central recess 21 is provided in the center of the lid member 20. Specifically, the central concave portion 21 is provided in a portion of the case member 10 that faces the fusible member accommodating portion 11, the terminal accommodating portion 12, and the positioning groove portion 15.

The lid side joint surface 22 is joined to the case side joint surface 13 of the case member 10 as shown in FIG. The lid-side joining surface 22 is formed in an annular shape along the outer edge of the bottom surface of the lid member 20 so as to surround the central recess 21. Here, the lid-side bonding surface 22 is bonded to the case-side bonding surface 13 with an epoxy-based adhesive to ensure airtightness.

The fitting recess 23 is fitted with the fitting protrusion 14 of the case member 10 as shown in FIG. 3A. The fitting recess 23 is formed by cutting out the side surface of the lid member 20 as shown in FIG. By adopting a configuration in which the fitting concave portion 23 is fitted with the fitting convex portion 14, the lid member 20 can be easily positioned with respect to the case member 10 when the case member 10 is covered with the lid member 20. 1 is improved.

The fitting recess 23 is joined to the fitting projection 14 with an adhesive. Specifically, the bottom surface 23 a (FIG. 9) of the fitting concave portion 23 is joined to the top surface 14 a (FIG. 7) of the fitting convex portion 14. For example, the bottom surface 23a is joined to the top surface 14a with an epoxy adhesive. Further, the side surface 14b (FIG. 7) of the fitting convex portion 14 is also joined to the side surface 23b (FIG. 9) of the fitting concave portion 23 with an epoxy adhesive. Thus, joining strength of case member 10 and lid member 20 can be raised more by joining fitting crevice 23 and fitting projection 14. As a result, the pressure resistance of the housing 5 in which the sealed space 6 in which the pressure increases is formed can be increased.

In the above description, the case member 10 has the fitting convex portion 14 and the lid member 20 has the fitting concave portion 23. However, the present invention is not limited to this. For example, the case member 10 has the fitting concave portion. And it is good also as the cover member 20 having a fitting convex part. That is, one of the case member 10 and the lid member 20 has a fitting convex portion, and the other has a fitting concave portion.

(Soluble body 30)
The fusible body 30 is a linear fuse element as shown in FIG. 2B. The fusible body 30 is provided in an aerial support state in the sealed space 6 in the housing 5. As shown in FIG. 4, the fusible body 30 is supported aerial in the sealed space 6 by being sandwiched between a pair of terminals 40 and 50 at both ends.

The fusible body 30 is made of nickel having a low thermal conductivity in this embodiment. However, it is not limited to this, The soluble body 30 may contain another metal which has nickel as a main component. That is, the soluble body 30 should just contain nickel as a base material. In such a case, even if the fusible body 30 generates heat during the operation of the chip fuse 1, the amount of heat transmitted to the terminals 40 and 50 is suppressed.

Further, the fusible body 30 has a fusible body plating layer whose surface is metal-plated. For example, the soluble body plating layer is a portion where the nickel surface of the soluble body 30 is tin-plated.

(Terminals 40, 50)
The pair of terminals 40 and 50 are provided on both ends in the longitudinal direction of the case member 10 as shown in FIG. 2B, and are connected to both ends of the fusible body 30. Here, the terminals 40 and 50 are made of a copper metal plate. The terminals 40 and 50 have a terminal plating layer in which metal plating (specifically, tin plating) is applied to the surface of the metal plate. The terminals 40 and 50 are electrically connected to the fusible body 30 by welding with the fusible body 30. Specifically, the terminals 40 and 50 are electrically connected to the fusible body 30 by melting and joining the terminal plating layers of the terminals 40 and 50 and the fusible body plating layer of the fusible body 30 by welding. Yes.

Further, the terminals 40 and 50 have an integrated structure with the housing 5 so that a part thereof is exposed from the housing 5. Specifically, the terminals 40 and 50 have an integral structure with the case member 10 by performing insert molding when the resin case member 10 is injection molded.

As shown in FIG. 4, the terminals 40 and 50 have clamping parts 41 and 51, through parts 42 and 52, and terminal parts 43 and 53. Since the configuration of the terminals 40 and 50 is the same, the detailed configuration of the terminal 50 will be described below.

The sandwiching portion 51 sandwiches the end of the fusible body 30 in the longitudinal direction. The clamping part 51 is accommodated in the terminal accommodating part 12 of the case member 10. The sandwiching part 51 includes a support part 511 and a pressing part 512.

The support portion 511 supports the end of the fusible body 30 in the longitudinal direction. Specifically, the support portion 511 supports the end of the fusible body 30 that is in contact with the upper surface of the support portion 511 (see FIG. 5). As shown in FIG. 5, the upper surface of the support portion 511 is located at the same height as the upper surface of the case member 10 (case-side bonding surface 13).

The pressing part 512 is opposed to the support part 511 and presses the end part supported by the support part 511 (see FIG. 5). The pressing part 512 is connected to the support part 511 and faces the support part 511 by bending a metal plate.

In addition, as shown in FIG. 6, the width W2 of the pressing portion 512 is smaller than the width W1 of the support portion 511. And the support part 511 is provided in the longitudinal direction (X direction of FIG. 6) of the fusible body 30 to the end side rather than the holding | suppressing part 512. As shown in FIG. That is, the position of the end surface 511 a of the support portion 511 is located on the outer side in the longitudinal direction than the position of the end surface 512 a of the pressing portion 512. In such a case, when the chip fuse 1 is assembled, the end of the fusible body 30 is cut off along the end surface 512a of the pressing portion 512 so that the end after cutting is located closer to the center than the end surface 511a of the support portion 511. Therefore, it is possible to prevent the end of the fusible body 30 from protruding to the case-side joining surface 13. As a result, it is possible to prevent the end of the fusible body 30 from being sandwiched between the case-side joining surface 13 and the lid-side joining surface 22 to reduce the airtightness.

As shown in FIG. 4, the penetrating part 52 penetrates the wall of the case member 10 and connects the clamping part 51 and the terminal part 53. The penetrating part 52 is joined to the penetrating wall, and the penetrating part 52 and the case member 10 are in close contact with each other. Moreover, the penetration part 52 becomes the shape which bent the metal plate several times. Specifically, the penetrating portion 52 has a shape bent in a staircase shape. The surface of the penetrating part 52 may be roughened by subjecting the surface of the penetrating part 52 that is in close contact with the case member 10 to a surface treatment. In such a case, since the penetrating part 52 and the case member 10 can be more closely attached, airtightness can be improved.

The terminal portion 53 is provided below the case member 10 so that a part thereof is exposed to the outside. The terminal portion 53 is connected to the circuit board when the chip fuse 1 is mounted on the circuit. As shown in FIG. 4, the terminal portion 53 is formed in an L shape, and includes a side terminal portion 531 and a bottom terminal portion 532.

The side terminal portion 531 is provided on the side surface of the case member 10 so as to be exposed to the outside. Specifically, as shown in FIG. 4, the outer surface of the side terminal portion 531 is located at the same position as the side surface of the case member 10. In such a case, when the chip fuse 1 is soldered to the circuit board, a solder fillet can also be formed on the side terminal portion 531, so that the terminal 50 can be reliably brought into contact with the circuit board. .

The bottom terminal portion 532 is located on the bottom surface of the case member 10. As shown in FIG. 4, the bottom surface of the bottom terminal portion 532 protrudes smaller than the thickness of the bottom terminal portion 532 with respect to the bottom surface of the case member 10. In such a case, when the chip fuse 1 is mounted on the circuit board, the bottom terminal portion 532 can reliably contact the circuit board. Further, since the portion of the bottom terminal portion 532 that does not protrude from the bottom surface of the case member 10 is integrated with the case member 10, the connection between the terminal 50 and the case member 10 becomes stronger.

(2-2. Characteristics of chip fuse 1)
The chip fuse 1 having the above-described configuration is a highly reliable chip fuse that ensures airtightness. This will be described in detail below.

(About airtightness of chip fuse 1)
As described above, in the chip fuse 1, the case member 10 and the lid member 20 that form the sealed space 6 are bonded to each other, so that airtightness can be stably secured. Further, since the case member 10 and the lid member 20 are formed of a liquid crystal polymer having excellent fluidity at the time of injection molding, the flatness of the case side joining surface 13 and the lid side joining surface 22 is high. For this reason, since the case-side joining surface 13 and the lid-side joining surface 22 are more likely to be in close contact with each other, the airtightness can be improved.

Moreover, since it becomes easy to apply | coat an adhesive agent to the whole surface of the case side joining surface 13 and the lid | cover side joining surface 22 which is a plane, while being able to suppress the fall of the airtightness resulting from the application | coating defect of the adhesive agent which generate | occur | produced conventionally, The workability of adhesive application is improved.

Further, since the case member 10 and the lid member 20 are formed of the same liquid crystal polymer, the case member 10 and the lid member 20 are joined by selecting an adhesive that is compatible with the liquid crystal polymer and joining the case member 10 and the lid member 20. The adhesive strength of the lid member 20 can be increased. In particular, it was confirmed from the experimental results that the epoxy adhesive used in the present embodiment can increase the adhesive strength between the case member 10 and the lid member 20 made of a liquid crystal polymer. In the experiment, the epoxy adhesive was cured at a temperature of about 130 ° C. for 30 minutes.

In addition, when the case member 10 and the lid member 20 are formed of the same material (liquid crystal polymer), it is possible to suppress the generation of thermal stress at the joint interface caused by the difference in linear expansion coefficient that occurs when different materials are used. . As a result, a decrease in bonding strength due to the generation of thermal stress can be suppressed. Further, by selecting an adhesive that matches the linear expansion coefficient of the liquid crystal polymer with that of the liquid crystal polymer, the bonding surface is peeled off due to temperature changes that occur repeatedly when the chip fuse 1 is used over a long period of time. Can be prevented.

Next, the airtightness due to the close contact between the case member 10 and the terminals 40 and 50 having an integral structure will be described.
As described above, the terminals 40 and 50 have the through portions 42 and 52 penetrating in a state where the terminals 40 and 50 are joined to the case member 10 between the sandwiching portions 41 and 51 and the terminal portions 43 and 53. Here, since the through portions 42 and 52 are formed in a staircase shape by bending the metal plates of the terminals 40 and 50, the joint area with the case member 10 can be widened. As a result, the airtightness can be sufficiently secured by joining the through portions 42 and 52 and the case member 10.

Further, since the liquid crystal polymer that is a material of the case member 10 has excellent fluidity, the liquid crystal polymer is formed through the through portions 42 and 52 when the case member 10 in which the through portions 42 and 52 are inserted is formed by insert molding. Therefore, the degree of close contact between the case member 10 and the through portions 42 and 52 can be increased.

(About the influence on the terminal when the fusible body generates heat)
In the present embodiment, the temperature rise of the terminals 40 and 50 (specifically, the sandwiching portions 41 and 51) electrically connected to the fusible body 30 can be suppressed by making the fusible body 30 made of nickel. Below, it demonstrates in contrast with the soluble body 902 (FIG. 1) made from copper demonstrated in the comparative example.

Hereinafter, for convenience of explanation, the soluble body 30 and the soluble body 902 will be simply referred to as a soluble body. In general, the amount of heat Q (W) transferred from the fusible body to the terminal per unit time is represented by the following equation (1).

Here, lambda represents the thermal conductivity of the fusible element (W / m · K), a represents the current cross-sectional area of the fusible (m ^2), L _e is the length of the fusible element (m), θ _m represents the melting point (K) of the soluble material, and θ _o represents the temperature of the terminal.

Next, in Formula (1), with the current cross-sectional area a, the length L _e , and the temperature θ _o being constant, the results of comparing the amount of heat Q when the fusible body is made of copper and when made of nickel are Table 1 shows. Here, a = 8.0 × 10 ⁻⁹ (m ² ), L _e = 0.0015 (m), and λ was a value at room temperature.

From Table 1, the amount of heat Q transferred from the nickel fusible body to the terminal is about 1/3 of the amount of heat transferred from the copper fusible body to the terminal when the temperature of the terminal is the same. I understand that In other words, when the fusible body is made of nickel, the amount of heat transferred to the terminal is small, so the temperature rise of the terminal is small.

Moreover, as can be seen from equation (1), the length L _e of the fusible element is reduced, the amount of heat Q that is transferred from the fusible element to the terminals is increased.
Therefore, in the length L _e is less fine chip fuse 1 of fusible 30 as in this embodiment, since the fusible element 30 is made of small nickel thermal conductivity, the terminal 40 from the fusible element 30, The amount of heat Q transmitted to 50 can be suppressed, and the temperature rise of terminals 40 and 50 can be suppressed. As a result, it is possible to suppress the influence of the heat generated from the fusible body 30 on the terminals 40 and 50 and the case member 10 that are integrated to improve airtightness.

According to the above-described chip fuse 1, the holding portions 41 and 51 of the terminals 40 and 50 hold and fix the fusible body 30, while the case-side joining surface 13 of the case member 10 and the lid-side joining surface of the lid member 20. 22 is joined to form a sealed space 6. In such a case, when the chip fuse 1 is operated, the heat of the fusible body 30 is not transmitted to the case-side joining surface 13 or the lid-side joining surface 22 even if it is transmitted to the sandwiching portions 41, 51. It can suppress that the joint strength of 13 and the lid side joint surface 22 falls. As a result, a decrease in the airtightness of the housing 5 can be suppressed.

Further, by making the base material of the case member 10 a liquid crystal polymer having excellent fluidity at the time of molding, adhesion between the terminals 40 and 50 and the case member 10 can be enhanced. Moreover, it becomes easy to perform joining by an adhesive agent effectively by making the case member 10 and the cover member 20 into the same material. Furthermore, the material of the fusible body 30 is made of nickel having a low thermal conductivity, so that the temperature rise of the sandwiching portions 41 and 51 of the terminals 40 and 50 can be suppressed during the operation of the chip fuse 1.
As a result of an experiment using the above-described chip fuse 1, it was confirmed that a current of 50 (A) can be cut off at a rated current of 250 (mA) and a rated voltage of 72 (V). In addition, it was confirmed that the same interruption was possible after repeated temperature cycle tests.

(2-3. Chip fuse manufacturing method)
An example of a method for manufacturing the chip fuse 1 having the above-described configuration will be described with reference to FIG.
FIG. 10 is a flowchart showing the manufacturing process of the chip fuse 1. Below, it demonstrates in detail for every process.

(Formation of terminals 40 and 50: S102)
FIG. 11 is a plan view of the case metal plate 600 in which the terminals 40 and 50 are formed. 12 is a view of the case metal plate 600 shown in FIG. 11 as viewed from the front side. FIG. 13 is a perspective view showing the terminals 40, 50 formed on the case metal plate 600.

In step S102, the case metal plate 600, which is a long first metal plate, is processed, and the pair of terminals 40, 50 are continuously formed on the case metal plate 600 at predetermined intervals.
The case metal plate 600 is a copper plate having a thickness of about 0.15 (mm), and the surface thereof is tin-plated. The case metal plate 600 is transported in a predetermined transport direction. The case metal plate 600 is provided with a conveying guide hole 602 at a predetermined pitch Lp in the longitudinal direction of the metal plate. As the conveying member rotates while sequentially meshing with the guide holes 602, the case metal plate 600 is conveyed in the conveying direction.

The terminals 40 and 50 are formed by press forming the case metal plate 600. The pair of terminals 40 and 50 are formed with the same pitch Lp as the pitch of the guide holes 602.
Further, the holding portions 4112 and 512 of the holding portions 41 and 51 of the terminals 40 and 50 stand perpendicular to the support portions 411 and 511 as shown in FIG. The holding parts 412 and 512 are bent and face the support parts 411 and 511 when fixing the fusible body 30 to the terminals 40 and 50.

The positional relationship between the guide hole 602 and the terminals 40 and 50 is determined in advance. For this reason, the position of the terminals 40 and 50 can also be managed by managing the position of the guide hole 602 of the case metal plate 600 being conveyed in the conveyance direction.

(Production of case assembly: S104)
FIG. 14 is a plan view of the case metal plate 600 in which the case assembly 650 is manufactured. FIG. 15 is a view of the case metal plate 600 shown in FIG. 14 as viewed from the front side.

In step S104, the case member 10 and the terminals 40, 50 are integrated by injection molding the thermoplastic resin, which is the material of the case member 10, onto the case metal plate 600 on which the terminals 40, 50 are formed. A case assembly 650 is produced. In the present embodiment, after the case metal plate 600 is set in an injection mold, the case assembly 650 is produced by injecting a liquid crystal polymer around the terminals 40 and 50 (so-called insert molding).

More specific explanation. First, the case metal plate 600 in which the terminals 40 and 50 are continuously formed is conveyed, and the conveyance stops when the terminals 40 and 50 are positioned in the mold (cavity or core) for the injection mold in the opened state. . Thereafter, the mold is closed and the liquid crystal polymer is injected into the mold to mold the case member 10 integrated with the terminals 40 and 50. That is, one case assembly 650 is manufactured. Then, the mold is opened again, and the case metal plate 600 is conveyed by a predetermined pitch, and the next case assembly 650 is manufactured. By repeating such a cycle, a large number of case assemblies 650 can be manufactured in a short time, and productivity can be improved.

As shown in FIG. 14, the plurality of case assemblies 650 are supported by the support portion 604 of the case metal plate 600 at a predetermined interval. In the case assembly 650, a part of the terminals 40 and 50 (specifically, the pressing portions 412 and 512 of the clamping portions 41 and 51) are exposed from the case member 10 without being covered with resin as shown in FIG. is doing.

As described above, the side surface terminal portions 431 and 531 of the terminal portions 43 and 53 of the terminals 40 and 50 are flush with the side surface of the case member 10 (see FIG. 4). In such a case, when the terminals 40 and 50 and the case member 10 are integrated by insert molding, the side terminal portions 431 and 531 come into contact with the inner surface of the injection mold and become stable. Can be performed with high accuracy.

(Fusion of soluble body: S106)
FIG. 16 is a plan view showing a state in which a long elongate fusible body 660 is disposed on a plurality of case assemblies 650. FIG. 17 is a longitudinal sectional view of the case assembly 650 of FIG. 18 is a cross-sectional view taken along line EE in FIG.

In step S106, the long fusible body 660 is disposed on the case member 10 of the case assembly 650, and the long fusible body 660 is fixed to the terminals 40 and 50. And after fixing the long soluble body 660, the long soluble body 660 and the terminals 40 and 50 are electrically connected. Hereinafter, details of this series of operations will be described.

First, the operation | work which arrange | positions the elongate soluble body 660 to the predetermined position of the case member 10 is demonstrated.
As described above, the pressing portions 412 and 512 of the holding portions 41 and 51 stand vertically with respect to the support portions 411 and 511. Then, the long fusible body 660 is moved from the upper side to the lower side of the sandwiching parts 41 and 51 to bring the long fusible body 660 into contact with the support parts 411 and 511. At this time, since the space above the support portions 411 and 511 is open, the long fusible body 660 can move and the position of the long fusible body 660 can be easily adjusted. In particular, by applying a predetermined tension to the long fusible body 660 supported at both ends, the linear long fusible body 660 with suppressed bending can be accurately positioned with respect to the support portions 411 and 511.

In this embodiment, the long fusible body 660 is arranged on each case member 10 of the plurality of case assemblies 650 so as to straddle the plurality of case assemblies 650 supported by the case metal plate 600. Here, since the support parts 411 and 511 with which the long fusible body 660 contacts and the case side joining surface 13 of the case member 10 are the same surface, the long fusible body 660 is positioned in the Z-axis direction. It becomes easy. Further, since the long fusible body 660 is disposed so as to pass through the positioning groove 15 of the case member 10, that is, the positioning groove 15 is also used as a guide, so that the long fusible body 660 can be easily positioned in the Y-axis direction. Become.

Next, the operation | work which fixes the elongate soluble body 660 arrange | positioned on the support parts 411 and 511 is demonstrated.
In a state in which the long fusible body 660 is disposed on the support portions 411 and 511, the holding portions 412 and 512 standing perpendicular to the support portions 411 and 511 are bent in the direction of the arrow shown in FIG. Specifically, the holding portions 412 and 512 are bent by about 90 degrees so that the holding portions 412 and 512 are opposed to the support portions 411 and 511 with the long fusible body 660 interposed therebetween. Thereby, the support parts 411 and 511 and the holding | suppressing parts 412 and 512 pinch the long soluble body 660. As a result, the long fusible body 660 positioned at a predetermined position is fixed to the holding portions 41 and 51.

Next, the operation | work which electrically connects both ends of the long soluble body 660 fixed to the clamping parts 41 and 51 and the terminals 40 and 50 is demonstrated.
In a state in which the long fusible body 660 is fixed to the sandwiching portions 41 and 51, a current is allowed to flow from the upper surface of the pressing portion 412 of the sandwiching portion 41 toward the support portion 411 with the long fusible body 660 interposed therebetween. One end of the solution 660 and the clamping part 41 are welded. Similarly, an electric current is passed from the upper surface of the pressing part 512 of the clamping part 51 toward the support part 511 with the long fusible body 660 interposed therebetween, and the other end of the long fusible body 660 and the clamping part 51 are welded. Thereby, the long soluble body 660 and the clamping parts 41 and 51 are electrically connected. In particular, during welding, the fusible body plating layer of the long fusible body 660 and the terminal plating layer of the sandwiching portions 41 and 51 are melted, so that the electrical connection between the long fusible body 660 and the terminals 40 and 50 is achieved. Connection can be realized reliably. In addition, you may weld the both ends of the elongate soluble body 660, and the clamping parts 41 and 51 simultaneously.

After connecting the long soluble body 660 and the terminals 40 and 50, the long soluble body 660 is cut. For example, the long fusible body 660 is cut with a cutter at the positions of the end faces 412a and 512a (FIG. 6) of the holding portions 412 and 512. The long fusible body 660 cut is the fusible body 30 of the chip fuse 1. As described above, since the end surfaces 411a and 511a of the support portions 411 and 511 are located outside the end surfaces 412a and 512a of the holding portions 412 and 512, the cutting position of the long fusible body 660 is temporarily shifted and the end portions are temporarily shifted. Even if it remains uncut, it is possible to prevent the fusible body 30 from protruding to the case-side joining surface 13 of the case member 10.

(Cover member molding: S108)
FIG. 19 is a plan view of a lid metal plate 700 on which the lid member 20 is formed. FIG. 20 is a view of the lid metal plate 700 shown in FIG. 19 as viewed from the front side.

In step S108, the thermoplastic resin, which is the material of the lid member 20, is injection-molded onto the long lid metal plate 700, so that the lid member is supported on the lid metal plate 700 at a predetermined interval. A plurality of 20 are molded. The lid metal plate 700 is, for example, a copper plate having a thickness of about 0.15 (mm), and the surface thereof is tin-plated. Similarly to the case metal plate 600, the guide metal plate 700 is provided with guide holes 702 at a pitch Lp. The lid member 20 is formed at the same pitch as the pitch of the guide holes 702.

The formed plurality of lid members 20 are supported by the support portion 704 of the lid metal plate 700. The positional relationship between the guide hole 702 and the lid member 20 is determined in advance. For this reason, the position of the lid member 20 can also be managed by managing the position of the guide hole 702 of the lid metal plate 700 being conveyed in the conveyance direction.

In the above description, the lid member is formed after the fusible body 30 is fixed. However, the present invention is not limited to this. For example, the lid member may be molded in parallel with the steps S104 and S106.

(Fuse assembly production: S110)
FIG. 21 is a longitudinal sectional view of a fuse assembly 800 in which the lid member 20 is joined to the case member 10 of the case assembly 650. FIG. 22 is a view showing a state where the fuse assembly 850 is supported by the case metal plate 600 and the lid metal plate 700.

In step S110, the case assembly 10 of the case assembly 650 supported by the case metal plate 600 and the lid member 20 supported by the lid metal plate 700 are combined to produce the fuse assembly 800. Specifically, the case metal plate 600 and the cover metal plate 700 are conveyed so that the case member 10 of the case assembly 650 is covered with the case member 10, and the case member 10 is assembled with the case member 10. At this time, the conveyance of the case metal plate 600 and the lid metal plate 700 is controlled using the guide holes 602 of the case metal plate 600 and the guide holes 702 of the lid metal plate 700. For example, the case metal plate 600 and the lid metal plate 700 are conveyed so that the guide hole 602 and the guide hole 702 coincide with each other.

Further, when the case member 10 and the lid member 20 are combined, the fitting convex portion 14 and the fitting concave portion 23 are fitted. Thereby, it becomes easy to assemble the lid member 20 at a desired position with respect to the case member 10.

When the lid member 20 is assembled to the case member 10, the case member 10 and the lid member 20 are joined. Specifically, an epoxy-based adhesive is applied to the case-side joining surface 13 of the case member 10 in advance. Thereafter, the case member 10 is covered with the lid member 20 and the case member 10 and the lid member 20 are pressurized and heated, so that the case side joining surface 13 of the case member 10 and the lid side joining surface 22 of the lid member 20 are formed. Join. Thereby, the fuse assembly 800 in which the fusible body 30 is sealed in the internal sealed space 6 can be manufactured.

In addition to the case-side joining surface 13, an epoxy adhesive is applied in advance to the fitting convex portion 14 of the case member 10. When the lid member 20 is assembled to the case member 10, the fitting convex portion 14 and the fitting concave portion 23 are joined with an adhesive. Thereby, the joint strength between the case member 10 and the lid member 20 can be increased.

As described above, the case assembly 650 is supported by the support portion 604 of the case metal plate 600, and the lid member 20 is supported by the support portion 704 of the lid metal plate 700. Therefore, the fuse assembly 800 obtained by combining the case member 10 and the lid member 20 of the case assembly 650 is also supported by the case metal plate 600 and the lid metal plate 700 as shown in FIG. . Note that, as illustrated in FIG. 22, the support portion 604 and the support portion 704 are located apart in the transport direction.

(Separation of metal plate for case: S112)
In step S112, fuse assembly 800 is separated from case metal plate 600. As a result, the terminals 40 and 50 of the separated fuse assembly 800 are insulated from the case metal plate 600. Specifically, the support portion 604 of the case metal plate 600 that supports the fuse assembly 800 is cut by, for example, a cutter, and the fuse assembly 800 is separated from the case metal plate 600. As described above, since the support portion 604 and the support portion 704 are separated from each other, for example, only the support portion 604 can be cut by a vertically moving cutter. At this time, the plurality of support portions 604 that support the fuse assembly 800 are simultaneously cut.

(Measurement of resistance value between terminals: S114)
In step S114, the resistance value between terminal 40 and terminal 50 of fuse assembly 800 separated from case metal plate 600 is measured. Although the fuse assembly 800 is supported by the lid metal plate 700, the terminals 40 and 50 are not electrically connected to the lid metal plate 700, so that they are insulated from the lid metal plate 700. State.

(Necessity determination of separation from metal plate for lid: S116)
In step S116, it is determined whether or not the fuse assembly 800 is separated from the lid metal plate 700 based on the measurement result of the resistance value between the terminals 40 and 50. Specifically, when the resistance value between the terminals 40 and 50 is within a predetermined range, it is determined that the fuse assembly 800 is a non-defective product, and the fuse assembly 800 whose resistance value is measured is used as the metal plate 700 for the lid. Separate from. That is, since the lid member 20 of the fuse assembly 800 is supported by the support portion 704 of the lid metal plate 700, the lid member 20 is separated from the lid metal plate 700.

Here, a method of separating the lid member 20 from the lid metal plate 700 will be described with reference to FIG.
23 is a cross-sectional view taken along line FF in FIG. As shown in FIG. 23, when the lid member 20 is supported by the support portion 704 of the lid metal plate 700, the tip 704a of the support portion 704 is fitted with the side recess 26 provided on the side surface of the lid member 20. Match. Here, since the fitting length between the tip 704a of the support portion 704 and the side recess 26 is small (for example, 0.1 mm), for example, when the operator pushes the tip 704a side of the support portion 704 by hand, the tip 704a And the fitting state of the side recess 26 is released. Thereby, even if it does not cut | disconnect with a cutter, the cover member 20 can be isolate | separated from the metal plate 700 for lid | covers.

On the other hand, if the measured resistance value is outside the predetermined range, it is determined that the fuse assembly 800 is defective and the fuse assembly 800 whose measured value is measured is not separated from the lid metal plate 700. As a result, only the fuse assembly 800 that has been determined to be non-defective is separated from the lid metal plate 700, so that it is possible to prevent a defective product from being mixed with a non-defective product.
Note that the state in which the fuse assembly 800 determined to be defective is supported by the lid metal plate 700 is maintained. However, the present invention is not limited to this. For example, the fuse determined to be defective in another process is used. The assembly 800 may be separated from the lid metal plate 700.

In the above description, the fuse assembly 800 is separated from the case metal plate 600 and the lid metal plate 700 in separate steps, but the present invention is not limited to this. For example, the separation from the case metal plate 600 and the separation from the lid metal plate 700 may be performed together in one step.

Alternatively, the fuse assembly 800 may be separated from the case metal plate 600 after being separated from the lid metal plate 700. In such a case, the resistance value between the terminals 40 and 50 is measured after the fuse assembly 800 is separated from the case metal plate 600.
Furthermore, in the above description, the fuse assembly 800 is separated from the lid metal plate 700 by manually pushing the tip 704a side of the support portion 704. However, the present invention is not limited to this. For example, when the fitting length between the tip 704a and the side recess 26 is large, the tip 704a side may be cut and separated by a cutter.

(2-4. Effects of this manufacturing method)
According to the manufacturing method of the chip fuse 1 described above, the fusible body 30 and the terminals 40 and 50 are electrically connected after fixing the fusible body 30 to the case member 10 with the upper portion of the case member 10 opened. Yes. And the chip fuse 1 in which the sealed space 6 in which the case member 10 and the lid member 20 are joined to seal the fusible body 30 is formed is manufactured.

In such a case, the fusible body 30 is disposed on the case member 10 with the upper portion of the case member 10 open, so that the workability of fixing the fusible body 30 is greatly improved. Also, by separating the work for fixing the fusible body 30 and the work for electrically connecting the fusible body 30 and the terminals 40, 50, the workability of each work is improved compared to the case where two works are performed simultaneously. Greatly improved. Moreover, since the case member 10 and the terminals 40 and 50 are integrated by insert molding, the sealing performance is deteriorated even when used for a long period of time compared to the case member 10 and the terminals 40 and 50 fixed with an adhesive. Can be suppressed. Further, the case member 10 is continuously formed on the case metal plate 600, and the case member 10 and the lid member 20 are combined after the plurality of cover members 20 are continuously formed on the lid metal plate 700. As a result, assembly and productivity are improved.

(2-5. Modifications)
In the above description, the housing 5 is made of a liquid crystal polymer, but is not limited thereto. For example, the housing 5 may be made of another thermoplastic resin. Further, the housing 5 may be made of a thermosetting resin.

In the above description, the case member 10 and the lid member 20 are joined with the epoxy adhesive, but the present invention is not limited to this. For example, the case member 10 and the lid member 20 may be joined with another adhesive. Further, the case member 10 and the lid member 20 may be joined by heat melting joining or ultrasonic joining instead of joining by an adhesive.

In the above, the fusible body 30 and the terminals 40 and 50 are joined by welding the plating layers, but the invention is not limited to this. For example, nickel which is the base material of the fusible body 30 and copper which is the base material of the terminals 40 and 50 may be melt-bonded.

In the above description, the width W1 of the support portions 411 and 511 is larger than the width W2 of the holding portions 412 and 512. However, the present invention is not limited to this. For example, the support portions 411 and 511 and the pressing portions 412 and 512 may have the same width, while the end portions 412a and 512a of the pressing portions 412 and 512 may be provided with notches. In such a case, the long soluble body 660 may be cut at the notch.

As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above embodiment. It is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Chip fuse 5 Case 6 Sealed space 10 Case member 13 Case side joint surface 14 Fitting convex part 15 Positioning groove part 20 Lid member 22 Lid side joint surface 23 Fitting concave part 30 Soluble body 40, 50 Terminal 41, 51 Holding part 42 , 52 Through part 43, 53 Terminal part 411, 511 Support part 412, 512 Holding part 431, 531 Side terminal part 432, 532 Bottom terminal part 600 Metal plate for case 650 Case assembly 700 Metal plate for lid 800 Fuse assembly

Claims (18)

1. A housing containing an insulating resin as a base material and forming a sealed space;
   A fusible body that is provided in an aerial support state in the sealed space and contains nickel as a base material;
   A pair of terminals electrically connected to both ends of the fusible body; and a structure that is integral with the housing such that a portion is exposed from the housing;
   A chip fuse.
2. The housing is
   A case member integrated with the terminal;
   A lid member that is joined to the facing case member and forms the sealed space with the case member;
   The chip fuse according to claim 1.
3. The case member has a case-side joint surface formed in an annular shape along the outer edge,
   The lid member has a lid side joining surface that is formed in an annular shape along an outer edge and joined to the case side joining surface,
   The chip fuse according to claim 2.
4. One of the case member and the lid member has a convex portion,
   The other of the case member and the lid member has a concave portion that is fitted to the convex portion,
   The top surface of the convex part and the bottom surface of the concave part are joined,
   The chip fuse according to claim 2 or 3.
5. The case member and the lid member are made of the same thermoplastic resin.
   The chip fuse according to any one of claims 2 to 4.
6. The terminal has a sandwiching portion that is provided in the sealed space and sandwiches an end portion in the longitudinal direction of the fusible body.
   The chip fuse according to any one of claims 2 to 5.
7. The clamping part is
   A support for supporting the end of the fusible body;
   A pressing part that faces the support part and presses the end part supported by the support part,
   In the longitudinal direction of the fusible body, the support portion is provided to the end side of the pressing portion,
   The chip fuse according to claim 6.
8. The upper surface of the support portion is located at the same height as the upper surface of the case member.
   The chip fuse according to claim 6 or 7.
9. The housing is formed between a fusing space where the fusible body is melted in the sealed space and the sandwiching portion, and has a groove part through which the fusible body passes.
   The chip fuse according to any one of claims 6 to 8.
10. The terminal is
    A terminal portion exposed to the outside in a state of being integrated with the sandwiching portion;
    A penetrating portion that penetrates the wall of the housing and connects the pinching portion and the terminal portion;
    The chip fuse according to any one of claims 6 to 9.
11. The terminal is made of a metal plate,
    The penetrating portion has a shape obtained by bending the metal plate a plurality of times.
    The chip fuse according to claim 10.
12. The terminal portion has a side terminal portion located on a side surface of the case member,
    The outer surface of the side terminal portion is located at the same position as the side surface of the case member.
    The chip fuse according to claim 10 or 11.
13. The terminal portion has a bottom terminal portion located on the bottom surface of the case member,
    The bottom surface of the bottom terminal portion protrudes smaller than the thickness of the bottom terminal portion with respect to the case member.
    The chip fuse according to any one of claims 10 to 12.
14. The fusible body has a fusible body plating layer to which metal plating is applied,
    The terminal has a terminal plating layer in which metal plating is applied to the surface of the metal plate,
    The terminal plating layer is joined and electrically connected to the fusible plating layer.
    The chip fuse according to claim 1.
15. Forming a case member including an insulating resin as a base material and a pair of metal terminals to produce a case assembly in which a part of the terminals are exposed from the case member;
    Arranging a fusible body containing at least nickel on the case member of the case assembly, and fixing the fusible body to the terminal;
    Bonding the lid member containing an insulating resin as a base material and the case member of the case assembly, and sealing the fusible body in a sealed space;
    A method of manufacturing a chip fuse.
16. The step of producing the case assembly includes:
    Processing a long first metal plate, and forming a plurality of the terminals at a predetermined interval on the first metal plate;
    Insulating resin is injection-molded with respect to the first metal plate so as to have an integral structure with each of the plurality of terminals, and the plurality of case members supported by the first metal plate at the predetermined interval are formed. Including the steps of:
    The method for manufacturing a chip fuse according to claim 15.
17. Injecting an insulating resin to the long second metal plate, and molding the plurality of lid members supported by the second metal plate at the predetermined interval;
    The case member of the case assembly supported by the first metal plate and the lid member supported by the second metal plate are joined and supported by the first metal plate and the second metal plate. Further comprising the steps of:
    The method for manufacturing a chip fuse according to claim 16.
18. Separating the fuse assembly from the first metal plate;
    Measuring a resistance value between the terminals of the fuse assembly separated from the first metal plate;
    Determining whether to separate the fuse assembly from the second metal plate based on the measurement result of the resistance value;
    Further having
    The method for manufacturing a chip fuse according to claim 17.
    

Images