阅读说明：本技术 保险丝 (Fuse wire ) 是由 井出浩树 岩田邦弘 于 2021-03-09 设计创作，主要内容包括：一种保险丝,具备：保险丝元件、壳体以及树脂制的成形体,所述保险丝元件沿着轴线延伸,具有两个端子和配置于所述两个端子之间的熔断部,所述壳体收纳所述熔断部及消弧剂,具有外周面和两个端面,是至少两个分割体的组装体,所述成形体具有将所述两个端面分别包覆的两个包覆部、和将所述两个包覆部连结的一个以上连结部,所述两个包覆部及所述一个以上连结部一体成形。所述壳体在所述外周面具有一个以上露出部。所述一个以上露出部没有被所述连结部包覆而露出。(A fuse is provided with: the fuse element includes two terminals and a fuse portion disposed between the two terminals, the case accommodates the fuse portion and an arc extinguishing agent, has an outer peripheral surface and two end surfaces, and is an assembly of at least two divided bodies, the molded body includes two covering portions covering the two end surfaces, and one or more connecting portions connecting the two covering portions, and the two covering portions and the one or more connecting portions are integrally molded. The housing has one or more exposed portions on the outer peripheral surface. The one or more exposed portions are exposed without being covered by the connecting portion.)

1. A fuse comprises a fuse element, a case and a resin molded body,

the fuse element extends along an axis, has two terminals and a fusing portion disposed between the two terminals,

the case is an assembly of at least two divided bodies, houses the fusing part and the arc extinguishing agent, and has an outer peripheral surface and two end surfaces,

the molded body has two covering parts for covering the two end faces respectively, and one or more connecting parts for connecting the two covering parts, the two covering parts and the one or more connecting parts are integrally molded,

the housing has one or more exposed portions on the outer peripheral surface, and the one or more exposed portions are exposed without being covered by the connecting portion.

2. The loaded fuse according to claim 1, wherein,

the at least two segments include a 1 st shell member and a 2 nd shell member,

the 1 st housing member and the 2 nd housing member each have the exposed portion.

3. The fuse according to claim 2,

the one or more coupling portions include a plurality of coupling portions arranged at intervals in a circumferential direction around the axis.

4. The fuse according to claim 3,

the one or more joint portions include two joint portions that seal between the 1 st housing member and the 2 nd housing member.

5. The fuse according to claim 4,

the two coupling parts are the 1 st coupling part,

the plurality of coupling portions further include two 2 nd coupling portions that cover an outer peripheral surface of the 1 st housing member and an outer peripheral surface of the 2 nd housing member, respectively.

Technical Field

The present disclosure relates to fuses.

Background

Japanese patent application laid-open No. 2018-129309 discloses a fuse used in, for example, an electric circuit for an automobile. The fuse includes a fuse element, a cylindrical case that houses the fuse element, two covers, and two holding plates. The housing has openings at both ends, respectively. The fuse element has two terminals protruding in opposite directions from each other, and a fuse portion disposed between the two terminals. Each terminal protrudes from a corresponding opening of the housing. Each terminal has an abutting piece. The two holding plates hold both ends of the fuse element, respectively. Each holding plate is inserted between the opening edge of the housing and the abutment piece. Each cover seals a corresponding opening of the housing so as to cover the outer peripheral surface of the housing and the holding plate. An arc extinguishing agent is contained in the case.

When an eddy current flows in a circuit including such a fuse, the fusing portion of the fuse element fuses due to joule heat of the eddy current. By thus cutting off the circuit, the circuit is protected.

Disclosure of Invention

Problems to be solved by the invention

An impact force is generated when the fusing part is fused. In the fuse of the above-mentioned japanese patent publication, the cover may be detached from the housing due to the above-mentioned impact force.

An object of the present disclosure is to provide a fuse capable of suppressing separation of a case.

Means for solving the problems

A fuse according to one aspect of the present disclosure includes a fuse element extending along an axis, having two terminals and a fuse portion disposed between the two terminals, a case housing the fuse portion and an arc extinguishing agent, and having an outer peripheral surface and two end surfaces, the case being an assembly of at least two divided bodies, the molded body having two covering portions covering the two end surfaces, respectively, and one or more connecting portions connecting the two covering portions, the two covering portions and the one or more connecting portions being integrally molded, the case having one or more exposed portions on the outer peripheral surface, the one or more exposed portions being exposed without being covered by the connecting portions.

Drawings

Fig. 1 is a perspective view of a fuse according to embodiment 1.

Fig. 2 is an exploded perspective view illustrating an internal structure of the fuse of fig. 1.

Fig. 3 is a sectional view taken along line 3-3 of fig. 1.

Fig. 4 is a perspective view of the fuse of embodiment 2.

Fig. 5 is an exploded perspective view illustrating an internal structure of the fuse of fig. 4.

Fig. 6 is a sectional view taken along line 6-6 of fig. 4.

Fig. 7 is a perspective view of a fuse element of modification 1.

Fig. 8 is a perspective view of a fuse according to modification 1.

Fig. 9 is a perspective view of a fuse according to modification 2.

Fig. 10 is a perspective view of an arc extinguishing agent according to modification 3.

Fig. 11 is an exploded perspective view showing an internal structure of a fuse of modification 4.

Fig. 12 is a sectional view of a fuse according to modification 4.

Detailed Description

< embodiment 1 >

Hereinafter, embodiment 1 of the fuse will be described with reference to fig. 1 to 3.

As shown in fig. 1 to 3, the fuse includes a fuse element 10, a case 20, an arc extinguishing agent 30, and a molded body 40. The fuse element 10 has an elongated plate shape, and an axis L (see fig. 2) of the fuse element 10 extends along the X axis. The Y axis is orthogonal to the X axis. The X axis represents an extending direction X in which the fuse element 10 extends, that is, a longitudinal direction of the fuse element 10.

The fuse element 10 includes two terminal portions 11 extending in opposite directions along the axis L, and a fuse portion 12 disposed between the two terminal portions 11. The width of the fusing portion 12 is smaller than the width of the two terminal portions 11. The fuse element 10 is made of copper or a copper alloy, for example.

The housing 20 is a hollow cylindrical body having an outer peripheral surface extending along the axis L and two end surfaces intersecting the axis L. The housing 20 is an assembly of at least two divided bodies having an outer shape in which an outer peripheral surface and both end surfaces are divided by a dividing surface including the axis L. The at least two divided bodies may include a 1 st shell member 21 and a 2 nd shell member 22 divided by a dividing surface. The direction in which the housing members 21, 22 are arranged is the dividing direction Y (the vertical direction in fig. 1 to 3).

As shown in fig. 2, the 1 st housing member 21 has two end walls 21A of a semicircular plate shape and a peripheral wall 21B extending between the two end walls 21A. Each end wall 21A has a recess 21C at a linear end edge.

The 2 nd housing member 22 has the same shape as the 1 st housing member 21, and has two end walls 22A, a peripheral wall 22B, and two recesses 22C. When the case members 21, 22 are assembled, a rectangular opening is defined by the recess 21C and the recess 22C.

The 1 st housing member 21 and the 2 nd housing member 22 are both made of thermoplastic resin. The 1 st housing member 21 and the 2 nd housing member 22 may be made of thermosetting resin. When the case members 21, 22 are assembled, the 1 st ends, i.e., the end walls 21A, 22A in the extending direction X of the case members 21, 22 become the 1 st circular end surface of the case 20, and the 2 nd ends, i.e., the end walls 21A, 22A become the 2 nd circular end surface of the case 20.

As shown in fig. 2 and 3, the fusing portion 12 of the fuse element 10 is housed in the case 20. Each terminal portion 11 protrudes outside the housing 20 through an opening defined by the concave portions 21C, 22C.

The arc extinguishing agent 30 is contained in the case 20. The arc suppressant 30 has a 1 st portion 31 and a 2 nd portion 32. The 1 st part 31 and the 2 nd part 32 have an outer shape obtained by dividing a solid cylinder extending along the axis L into two parts by a dividing plane including the axis L. The 1 st portion 31 is received in the 1 st housing member 21. The 2 nd portion 32 is received within the 2 nd housing member 22. The 1 st segment 31 has a rectangular cut surface facing the fuse element 10, and a recess 31a opened in the cut surface. The fuse element 10 is disposed in the recess 31 a. The concave portion 31a is shaped along the end portions of the fuse portion 12 and the two terminal portions 11 connected to the fuse portion 12.

As shown in fig. 1 and 3, the molded body 40 has two disk-shaped coating portions 41. The two covering portions 41 cover the respective end surfaces of the housing 20. In other words, each covering portion 41 covers the end walls 21A, 22A.

The molded body 40 has one or more coupling portions 42 that couple the two covering portions 41. The two covering portions 41 and the one or more connecting portions 42 are integrally formed. The one or more coupling portions 42 may include a plurality of coupling portions 42 arranged at intervals in the circumferential direction around the axis L. The one or more coupling parts 42 include, for example, two 1 st coupling parts 43 and two 2 nd coupling parts 44.

The two 1 st coupling portions 43 seal the 1 st ends of the housing members 21, 22 in the circumferential direction from each other and the 2 nd ends of the housing members 21, 22 in the circumferential direction from each other, respectively. That is, the two 1 st coupling portions 43 seal the space between the peripheral wall 21B and the peripheral wall 22B.

The two 2 nd coupling portions 44 cover a part of the outer peripheral surfaces of the housing members 21, 22, respectively. Each 2 nd coupling portion 44 is located between two 1 st coupling portions 43 in the circumferential direction. The two 1 st coupling parts 43 protrude in opposite radial directions from each other along the dividing plane. The two 2 nd coupling portions 44 project radially opposite to each other along the Y axis. The 1 st coupling portion 43 and the 2 nd coupling portion 44 are alternately arranged at intervals in the circumferential direction around the axis L.

The molded body 40 is made of a thermoplastic resin.

The housing 20 has one or more exposed portions 50 on the outer peripheral surface. The exposed portion 50 is exposed without being covered by the coupling portion 42. Each of the housing members 21, 22 has one or more exposed portions 50. More specifically, each of the peripheral wall 21B and the peripheral wall 22B has two exposed portions 50 not covered by the connection portion 42.

The formed body 40 is formed by the following steps.

First, the 1 st part 31 is housed in the 1 st case member 21, and the fuse element 10 is housed in the recess 31a of the 1 st part 31. The 1 st housing member 21, the 1 st segment 31, and the fuse element 10, which are nested in this manner, have the 2 nd segment 32 of the arc extinguishing agent 30 placed thereon. Next, the 2 nd housing member 22 is covered on the 2 nd portion 32. Thereby, the portion of the fuse element 10 including the fusing portion 12 and the arc extinguishing agent 30 are housed between the 1 st case member 21 and the 2 nd case member 22. Next, the assembly of the fuse element 10, the 1 st case member 21, the 2 nd case member 22, and the arc extinguishing agent 30 is fitted into a mold, and a molten resin is injected into a cavity (all of which are not shown) in the mold. The resin in the mold is cooled and plasticized to form a resin molded body 40. At this time, the exposed portion 50 is a portion of the outer peripheral surface of the housing members 21 and 22 where the mold contacts.

Next, the operation and effect of the present embodiment will be described.

(1) The gap between the fuse element 10 and the case 20 is sealed by covering both end surfaces of the case 20 with the two covering portions 41. In addition, since the two covering portions 41 are coupled by the one or more coupling portions 42, separation of the 1 st and 2 nd casing members 21 and 22 due to an impact at the time of fusing the fusing portion 12 can be suppressed. Therefore, separation of the housing 20 can be suppressed.

Further, since the case 20 has the exposed portion 50, the performance of releasing the joule heat generated inside the case 20 to the outside of the case 20, that is, the heat radiation performance of the case 20 can be improved as compared with the comparative example in which the entire outer peripheral surface of the case 20 is covered with the resin.

(2) Since the case members 21 and 22 each have the exposed portion 50, the heat dissipation performance of the case 20 can be further improved.

Further, according to the above configuration, when the case 20 containing the fuse portion 12 and the arc extinguishing agent 30 is fitted into a mold and the molded body 40 is injection molded, the portion of the case members 21 and 22 that contacts the mold becomes the exposed portion 50. Therefore, the case members 21 and 22 can be supported by the molds during the molding of the molded body 40, and the 1 st case member 21 and the 2 nd case member 22 can be prevented from being separated from each other.

(3) Since the plurality of coupling portions 42 are arranged at intervals in the circumferential direction around the axis L, the rigidity of the molded body 40 is improved. Therefore, the 1 st shell member 21 and the 2 nd shell member 22 can be further suppressed from being separated by an impact at the time of fusing the fusing part 12.

(4) The plurality of coupling portions 42 include two 1 st coupling portions 43 that seal between the 1 st housing member 21 and the 2 nd housing member 22. Therefore, the arc extinguishing agent 30 can be prevented from leaking out from between the 1 st and 2 nd case members 21 and 22.

(5) Since the molded body 40 has two 2 nd coupling parts 44 in addition to the two 1 st coupling parts 43, the rigidity of the molded body 40 is improved. Therefore, the 1 st shell member 21 and the 2 nd shell member 22 can be further suppressed from being separated by an impact at the time of fusing the fusing part 12.

< embodiment 2 >

Hereinafter, embodiment 2 will be described mainly focusing on differences from embodiment 1 with reference to fig. 4 to 6. Note that, in the configuration of the present embodiment, the same reference numerals as those of embodiment 1 are given to the configuration corresponding to embodiment 1, and overlapping description is omitted.

As shown in fig. 4 to 6, the fuse includes a fuse element 10, a case 20, an arc extinguishing agent 30, and a molded body 40. The housing 20 is an assembly of a 1 st housing member 21 and a 2 nd housing member 22 as two divided bodies.

As shown in fig. 5, the housing 20 is a hollow rectangular parallelepiped.

As shown in fig. 5 and 6, the 1 st housing member 21 is a box that is open in a direction perpendicular to the axis L (upward in fig. 5), and has a rectangular plate-shaped end wall 211, two side walls 212, and two side walls 213. The two side walls 212 are opposed to each other. The two side walls 213 extend between each other at the 1 st end and the 2 nd end of the two side walls 212, respectively. Each side wall 212 has a slit-shaped recess 21C extending along the Y axis. Four corners defined between the side walls 212, 213 adjacent to each other have chamfered portions 21D, respectively. These chamfered portions 21D are disposed in the opening end region of the 1 st case member 21.

The 2 nd housing member 22 has a rectangular plate-like top wall 221 that closes the opening of the 1 st housing member 21, and four leg portions 22D. The four leg portions 22D protrude from the four corners of the top wall 221 toward the corresponding chamfered portions 21D, respectively.

Each leg 22D is engaged with the corresponding chamfered portion 21D, whereby the 2 nd housing member 22 is positioned with respect to the 1 st housing member 21.

The width direction of the fuse element 10 is along the Y axis, i.e., the extending direction of the concave portion 21C.

The arc suppressant 30 has a 1 st portion 31 and a 2 nd portion 32. The 1 st portion 31 has a substantially rectangular parallelepiped shape and is disposed so as to face the 1 st surface of the fuse element 10. The 2 nd portion 32 has a rectangular parallelepiped shape and is disposed so as to face the 2 nd surface of the fuse element 10 on the side opposite to the 1 st surface. A surface of the 1 st portion 31 facing the fuse element 10 is opened with a recess 31a for accommodating the fuse element 10. The concave portion 31a is shaped along the end portions of the fuse portion 12 and the two terminal portions 11 connected to the fuse portion 12.

As shown in fig. 4 and 6, the molded body 40 has two covering portions 41 in the form of a rectangular plate. Each covering portion 41 covers the outer surface of the corresponding side wall 212 and the outer surface of the top wall 221. That is, the two covering portions 41 cover the two end surfaces of the housing 20 intersecting the axis L.

The plurality of coupling portions 42 include two 1 st coupling portions 43 and two 2 nd coupling portions 44. Each 1 st coupling portion 43 seals between the corresponding side wall 212 and the top wall 221.

The exposed portion 50 is a portion of the outer peripheral surface of the housing 20, specifically, the outer surface of the end wall 211, the outer surface of the side wall 213, and the outer surface of the top wall 221, which is not covered with the coupling portion 42. Therefore, the exposed portion 50 is disposed on both the case members 21 and 22.

According to the present embodiment, the same operational effects as those (1) to (5) of embodiment 1 can be obtained.

< modification example >

The above embodiment can be modified as follows, for example. The present embodiment and the following modifications can be combined and implemented within a range not technically contradictory to each other.

A plurality of the 2 nd coupling parts 44 may be disposed between the two 1 st coupling parts 43.

One or both of the two 2 nd connecting parts 44 may be omitted.

When the molded body 40 has the 2 nd coupling part 44, one or both of the 1 st coupling parts 43 may be omitted. That is, the molded body 40 may have a coupling portion 42 that does not seal between the 1 st housing member 21 and the 2 nd housing member 22.

The molded body 40 may include at least one coupling portion 42.

The exposure portion 50 may be disposed on either one of the case members 21 and 22. At least one of the shape and size of the exposed portion 50 can be changed as appropriate.

The dividing direction Y of the case members 21 and 22 may be a direction intersecting the axis L (extending direction X), and may not be orthogonal to the axis L.

The shape of the fuse element 10 is not limited to the shape exemplified in embodiments 1 and 2. For example, as in modification 1 shown in fig. 7, the fuse element 10 may have two thick plate portions 13, and the two thick plate portions 13 may be disposed at the ends of the two terminal portions 11 connected to the fuse portion 12. Each thick plate portion 13 protrudes toward both sides in the thickness direction of the fuse element 10.

In modification 1, as shown in fig. 8, when the exposed portion 50 is disposed on a portion of the outer peripheral surface of the case 20 corresponding to the thick plate portion 13, more specifically, a portion of the case 20 overlapping the thick plate portion 13 in the radial direction thereof, the heat radiation performance of the case 20 is improved. The exposed portion 50 may be provided only in a portion of the housing 20 that overlaps the thick plate portion 13 in the radial direction thereof.

A plurality of fuses may be integrated by the molded body 40. For example, as in the 2 nd modification shown in fig. 9, three fuse elements 10 may be arranged in the width direction, and the molded body 40 having the shape exemplified in embodiment 1 may be integrally formed. In the 2 nd modification, two 1 st coupling portions 43 adjacent to each other are integrally formed by a coupling wall 45. In this way, the molded body 40 covering the case 20 can easily integrate the fuse with another fuse or another member.

The 1 st part 31 may not have the recess 31 a. That is, the 1 st portion 31 and the 2 nd portion 32 may have the same shape.

The arc extinguishing agent 30 is not limited to the assembly of the plurality of segments. For example, the arc extinguishing agent 30 may have a substantially cylindrical shape. In this case, as in the modification 3 shown in fig. 10, the arc extinguishing agent 30 may have a notch 30a that penetrates the arc extinguishing agent 30 along the axis L and opens on the outer peripheral surface, and the fuse element 10 may be accommodated in the notch 30 a.

The arc extinguishing agent 30 is not limited to the solid described in the above embodiments or modifications, and may be a powder.

Fig. 11 and 12 show a fuse according to a 4 th modification. The fuse is provided with a powder arc-extinguishing agent 30. In the case of manufacturing this fuse, first, the fuse element 10 is inserted into the inside of the 1 st case member 21 and the two concave portions 21C. Next, the 2 nd case member 22 is assembled with respect to the 1 st case member 21. Next, the arc extinguishing agent 30 in powder form is filled into the case 20 through the hole 222 provided in the top wall 221 of the 2 nd case member 22. Next, the key 223 is inserted into the hole 222. Next, the assembly of the fuse element 10, the 1 st case member 21, the 2 nd case member 22, the plug body 223, and the arc extinguishing agent 30 is fitted into a mold, and a molten resin is injected into a cavity (all of which are not shown) in the mold. Thereby, the molded body 40 is formed. When the molded body 40 is formed, the entire plug 223 is covered with the 2 nd coupling portion 44.

The housing 20 may be an assembly of three or more divided bodies.