fuse

Abstract

To provide a fuse that effectively prevents a housing from expanding due to internal pressure.SOLUTION: A fuse 500 includes a fuse element 400 having a fusing portion 420 provided between a pair of terminal parts 410, and a housing 300 that houses the fuse element 400, and the housing 300 includes a wall portion, and the housing 300 is provided with at least one reinforcing portion (350, 360) that connects the wall portions.SELECTED DRAWING: Figure 7

Description

[Technical field]

[0001] The present invention relates to a fuse used primarily in automotive electrical circuits, and more particularly to a fuse having a fuse element housed within a casing. [Background technology]

[0002] Fuses have traditionally been used to protect electrical circuits mounted on automobiles and the like, as well as various electrical equipment connected to the electrical circuits. More specifically, when an unintended overcurrent flows through an electrical circuit, the fusing part of the fuse element built into the fuse melts due to heat generated by the overcurrent, thereby protecting the various electrical equipment from excessive current flowing through them.

[0003] There are various types of fuses depending on the application. For example, the fuse described in Patent Document 1 is known.

[0004] The fuse described in Patent Document 1 is a type that houses a fuse element inside a housing, and includes a fuse element having a pair of terminal parts and a fusing part provided between the terminal parts. In recent years, in order to accommodate higher voltages and larger currents, it is desirable to increase the number of fusing parts and increase the fuse capacity. If the number of fusing parts is increased, the housing may expand due to the internal pressure of gas generated when the fusing part is blown. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-93323 DISCLOSURE OF THEINVENTION [Problem to be solved by the invention]

[0006] Therefore, the present invention provides a fuse that effectively prevents the housing from expanding due to internal pressure. [Means for solving the problem]

[0007] The fuse of the present invention is a fuse comprising a fuse element having a melting portion provided between a pair of terminal portions, and a housing that accommodates the fuse element, wherein the housing has a wall portion, and the housing is provided with at least one reinforcing portion connecting the wall portions.

[0008] According to the above feature, the reinforcing portion strongly reinforces the housing so that the housing does not expand and deform due to the internal pressure.

[0009] Furthermore, the fuse of the present invention is characterized in that the housing comprises one housing segment and the other housing segment, and the reinforcing portion is provided so as to traverse the housing segments on both sides.

[0010] According to the above feature, the reinforcing portion effectively prevents the housing split pieces from expanding in directions away from each other due to internal pressure.

[0011] Furthermore, the fuse of the present invention is characterized in that the reinforcing portion comprises one divided portion and the other divided portion, the one divided portion being provided on the one housing divided piece and the other divided portion being provided on the other housing divided piece, and the one divided portion and the other divided portion are configured to be connected and fixed to each other.

[0012] According to the above feature, each split portion can be formed at the same time that each housing split piece is formed by a conventional method for forming each housing split piece (for example, injection molding, etc.).

[0013] Furthermore, the fuse of the present invention is characterized in that the tip of one of the split portions and the tip of the other of the split portions are connected and fixed by fitting together.

[0014] According to the above feature, one housing split piece and the other housing split piece can be simply assembled by facing each other and sandwiching them together, so that one split portion fits directly into the other split portion, making it easy to connect and fix the split portions.

[0015] Furthermore, in the fuse of the present invention, the reinforcing portion is provided on the one housing half, and a tip of the reinforcing portion is connected and fixed to the other housing half.

[0016] According to the above feature, the reinforcing portion effectively prevents the housing split pieces from expanding in directions away from each other due to internal pressure.

[0017] Furthermore, the fuse of the present invention is characterized in that the reinforcing portion is spaced apart from the inner side surface of the accommodating space.

[0018] According to the above feature, the reinforcing portion does not divide the storage space into left and right parts, and the storage space around the reinforcing portion is connected by the communication space. Therefore, the arc-extinguishing material poured into one part of the storage space flows around the reinforcing portion and reaches the entire storage space, even if the reinforcing portion exists, and the entire storage space is filled without any gaps. Effect of the Invention

[0019] As described above, the fuse of the present invention can effectively prevent the housing from expanding due to internal pressure. [Brief description of the drawings]

[0020] [Figure 1] FIG. 2 is an overall perspective view of one housing split piece of the fuse according to the present invention. [Diagram 2] 4A is a plan view of a housing split piece, and FIG. 4B is a front view of the housing split piece. [Diagram 3] 2(a) is a cross-sectional view taken along line AA in FIG. 2(a), and FIG. 2(b) is a cross-sectional view taken along line BB in FIG. 2(a). [Figure 4] 11 is an overall perspective view of the other housing split piece of the fuse according to the present invention. FIG. [Diagram 5] 4A is a plan view of a housing split piece, and FIG. 4B is a front view of the housing split piece. [Figure 6] 5(a) is a cross-sectional view taken along line CC shown in FIG. 5(a), and FIG. 5(b) is a cross-sectional view taken along line DD shown in FIG. 5(a). [Figure 7] FIG. 2 is an exploded perspective view of the fuse according to the present invention. [Figure 8] FIG. 2A is a plan view of the fuse in an assembled state, and FIG. 2B is a front view of the fuse in an assembled state. [Figure 9] 8(a) is a cross-sectional view taken along line EE shown in FIG. 8(a), and FIG. 8(b) is a cross-sectional view taken along line FF shown in FIG. 8(a). [Explanation of symbols]

[0021] 300 Housing 340 Storage Space 350 Reinforcement 360 Reinforcement 400 Fuse Element 410 Terminal section 420 Melting point 500 Fuse DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0022] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the shapes, materials, and the like of each component of the fuse in the embodiments described below are merely examples and are not intended to be limiting.

[0023] Figures 1 to 3 show housing split pieces 100 constituting a housing 300 of a fuse according to the present invention. Figure 1 is an overall perspective view of the housing split piece 100, Figure 2(a) is a plan view of the housing split piece 100, Figure 2(b) is a front view of the housing split piece 100, Figure 3(a) is a cross-sectional view taken along line A-A in Figure 2(a), and Figure 3(b) is a cross-sectional view taken along line B-B in Figure 2(a).

[0024] The housing split piece 100 is made of synthetic resin and has a generally rectangular parallelepiped shape, and includes an upper wall 110 that forms the top surface, side walls 120 that form the sides, and front and rear walls 130 that form the front and rear surfaces. The housing split piece 100 includes an accommodation space 140 that is surrounded by the upper wall 110, the left and right walls 120, and the front and rear walls 130. The lower side of the accommodation space 140 is an opening surface 141 that is disposed so as to face an opening surface 241 of an accommodation space 240 of a housing split piece 200, which will be described later. Furthermore, the ends of the walls 120 and 130 are provided with mating protrusions 121 that protrude downward, and the mating protrusions 121 are fitted into mating recesses 222 of the housing split piece 200, which will be described later. Further, ends of the wall portion 120 and the wall portion 130 are provided with inwardly recessed mating recesses 122 into which mating protrusions 221 of the housing split pieces 200 described later fit. Further, an insertion portion 131 having a recessed shape is formed at the end of the wall portion 130 so that a terminal portion 410 of the fuse element 400 described later can be inserted therethrough.

[0025] Furthermore, the housing space 140 of the housing split piece 100 is provided with a central split part 150 and split parts 160 on both sides of the split part 150. The central split part 150 and the split parts 160 on both sides are connected and fixed to a central split part 250 and a split part 260 on both sides of the housing split piece 200, which will be described later, respectively, to form a single reinforcing part. The base part 151 of the split part 150 is fixed to the approximate center of the wall part 110 constituting the top surface, and a tip part 152 hangs down linearly downward. The tip part 152 is further provided with a fitting protrusion 153 that is convex downward, and the fitting protrusion 153 is configured to fit into a fitting recess 253 of the housing split piece 200, which will be described later. Similarly, the base part 161 of the split part 160 is fixed to the vicinity of the end part of the wall part 110 constituting the top surface, and a tip part 162 hangs down linearly downward. Furthermore, tip 162 is provided with a downwardly protruding mating protrusion 163 that is configured to fit into a mating recess 263 of housing split piece 200, which will be described later. Split portion 160 is also connected and fixed to the inside of wall portion 130. Furthermore, base portion 151 of split portion 150 and base portion 161 of split portion 160 are connected and fixed to each other by a base reinforcement body 159 that extends along wall portion 110 that forms the top surface.

[0026] Next, Fig. 4 to Fig. 6 show housing split pieces 200 constituting a housing 300 of the fuse according to the present invention. Fig. 4 is an overall perspective view of housing split piece 200, Fig. 5(a) is a plan view of housing split piece 200, Fig. 5(b) is a front view of housing split piece 200, Fig. 6(a) is a cross-sectional view taken along CC shown in Fig. 5(a), and Fig. 6(b) is a cross-sectional view taken along D-D shown in Fig. 5(a).

[0027] The housing split piece 200 is made of synthetic resin and has a generally rectangular parallelepiped shape, and includes a lower wall 210 that forms the bottom surface, side walls 220 that form the sides, and front and rear walls 230 that form the front and rear surfaces. The housing split piece 200 includes an accommodation space 240 that is surrounded by the lower wall 210, the left and right walls 220, and the front and rear walls 230. The upper side of the accommodation space 240 is an opening surface 241, which is disposed so as to face the opening surface 141 of the accommodation space 140 of the housing split piece 100. Furthermore, the ends of the walls 220 and 230 are provided with mating protrusions 221 that protrude upward, and the mating protrusions 221 are fitted into the mating recesses 122 of the housing split piece 100. Further, ends of the wall portion 220 and the wall portion 230 are provided with inwardly recessed mating recesses 222 into which the mating protrusions 121 of the housing split piece 100 fit. Further, an insertion portion 231 having a recessed shape is formed at the end of the wall portion 230 so that a terminal portion 410 of the fuse element 400 described later can be inserted therethrough.

[0028] Furthermore, the housing space 240 of the housing split piece 200 is provided with a central split part 250 and split parts 260 on both sides of the split part 250. The base part 251 of the split part 250 is fixed to the approximate center of the wall part 210 constituting the bottom surface, and a tip 252 protrudes upward in a straight line. The tip 252 is provided with a fitting recess 253 that is concave downward, and this fitting recess 253 is configured to fit with the fitting protrusion 153 of the housing split piece 100. Similarly, the base part 261 of the split part 260 is fixed to the vicinity of the end of the wall part 210 constituting the bottom surface, and a tip 262 protrudes upward in a straight line. The tip 262 is provided with a fitting recess 263 that is concave downward, and this fitting recess 263 is configured to fit with the fitting protrusion 163 of the housing split piece 100. Moreover, the divided portion 260 is connected and fixed to the inside of the wall portion 230. Furthermore, the base portion 251 of the divided portion 250 and the base portion 261 of the divided portion 260 are connected and fixed to each other by a base reinforcing body 259 extending along the wall portion 210 that constitutes the bottom surface.

[0029] Next, a mode of assembling the fuse 500 of the present invention will be described with reference to Fig. 7 to Fig. 9. Fig. 7 is an exploded perspective view of the fuse 500, Fig. 8(a) is a plan view of the fuse 500 in an assembled state, Fig. 8(b) is a front view of the fuse 500 in an assembled state, Fig. 9(a) is a cross-sectional view taken along line E-E in Fig. 8(a), and Fig. 9(b) is a cross-sectional view taken along line F-F in Fig. 8(a).

[0030] 7, fuse element 400 is formed into an elongated shape from one thin metal plate, and includes a pair of terminal portions 410 and a flat, elongated circuit portion 430 between terminal portions 410. Circuit portions 430 of fuse element 400 are connected in parallel with each other, and each circuit portion 430 has a plurality of fusion portions 420 formed therein. Fusion portions 420 are formed with a plurality of small holes 421.

[0031] Although fuse element 400 includes two circuit portions 430, the present invention is not limited thereto and may include one circuit portion 430 or three or more circuit portions 430. Furthermore, although fusing portion 420 is formed by drilling a plurality of small holes 421, the present invention is not limited thereto and may include, for example, a fusing portion formed by locally thinning the thickness of circuit portion 430, or a fusing portion formed by depositing a low melting point metal such as tin, lead, silver, nickel, or an alloy thereof in a narrow portion of circuit portion 430.

[0032] 7, when assembling fuse 500, housing split pieces 100 and 200 are attached so as to sandwich fuse element 400 from above and below, and melting portion 420 of fuse element 400 is accommodated inside housing 300. Specifically, fuse element 400 is placed on opening surface 241 of accommodation space 240 of lower housing split piece 200, and terminal portion 410 of fuse element 400 is fitted into insertion portion 231 of housing split piece 200. Center split portion 250 and both side split portions 260 are located in gaps 440 between circuit portions 430 of fuse element 400.

[0033] Next, the upper housing split piece 100 is placed over the housing split piece 200 so that the opening surface 141 of the accommodation space 140 of the upper housing split piece 100 covers the fuse element 400, and the insertion portion 131 of the housing split piece 100 is fitted into the terminal portion 410 of the fuse element 400. The central split piece 150 and the split pieces 160 on both sides are located in the gap 440 between the circuit portion 430 of the fuse element 400, and the fitting convex portion 153 of the upper split piece 150 fits into the fitting concave portion 253 of the lower split piece 250, and are firmly fixed to each other. In particular, simply by assembling the upper housing split piece 100 and the lower housing split piece 200 so as to sandwich them facing each other, the fitting convex portion 153 of the upper split piece 150 fits directly into the fitting concave portion 253 of the lower split piece 250, and therefore one split piece 150 and the other split piece 250 can be easily connected and fixed.

[0034] Similarly, the mating protrusion 163 of the upper split piece 160 fits into the mating recess 263 of the lower split piece 260, and they are firmly fixed to each other. Furthermore, the mating protrusion 121 of the housing split piece 100 fits into the mating recess 222 of the housing split piece 200, and the mating protrusion 221 of the housing split piece 200 fits into the mating recess 122 of the housing split piece 100, so that the mating between the housing split pieces 100 and 200 becomes even stronger.

[0035] Although the fitting convex portion 153 of the upper divided portion 150 is fitted into the fitting concave portion 253 of the lower divided portion 250, the present invention is not limited thereto, and as long as the upper divided portion 150 and the lower divided portion 250 can be connected and fixed to each other, any method can be adopted, such as a method of connecting and fixing one divided portion 150 and the other divided portion 250 with an adhesive, a method of connecting and fixing one divided portion 150 and the other divided portion 250 with a fastening member such as a screw, or a method of connecting and fixing one divided portion 150 and the other divided portion 250 with a locking member such as a hook. Similarly, the fitting convex portion 163 of the upper divided portion 160 is fitted into the fitting concave portion 263 of the lower divided portion 260, the present invention is not limited thereto, and as described above, any fixing method can be adopted.

[0036] In this manner, housing 300 including one housing split piece 100 and the other housing split piece 200 accommodates fusing portion 420 of fuse element 400 by sandwiching it from above and below, thereby assembling fuse 500. Then, as shown in Figures 8 and 9, accommodation space 340 consisting of upper and lower accommodation spaces (140, 240) accommodates fusing portion 420 of circuit section 430 of fuse element 400 so as to surround the periphery of fusing portion 420.

[0037] The accommodating space 340 is filled with a granular arc-extinguishing material (not shown) in the same manner as in the past. For example, the arc-extinguishing material is poured into the accommodating space 340 through a filling hole 301 in the housing 300, and then the filling hole 301 is sealed. At this time, the reinforcing part 350 formed by connecting and fixing the divided part 150 and the divided part 250 is located approximately in the center of the accommodating space 340 and is separated from the inner surface 341 around the accommodating space 340, so that a communication space 342 is secured between the periphery of the reinforcing part 350 and the inner surface 341 of the accommodating space 340. In other words, the reinforcing part 350 does not divide the accommodating space 340 into left and right parts, and the accommodating space 340 around the reinforcing part 350 communicates with each other through the communication space 342. Therefore, the arc-extinguishing material poured into one part of the storage space 340 flows around the reinforcing portion 350 and reaches the entire storage space 340, even though the reinforcing portion 350 is present, so that the entire storage space 340 is filled securely with no gaps.

[0038] The fuse 500 is mounted by connecting the terminal portion 410 protruding laterally from the housing 300 to an external electric circuit. When an unintended overcurrent flows in an electric circuit, the fusing portion 420 of the fuse element 400 generates heat and melts, thereby interrupting the overcurrent. In addition, an arc that is generated when the fusing portion 420 melts is quickly extinguished by the surrounding arc-extinguishing material.

[0039] Here, in order to cope with high voltage and large current, fuse 500 is provided with a plurality of fusion parts 420. Then, as shown in FIG. 9, the internal pressure P of the gas generated when fusion parts 420 are fused increases, and a load is applied to expand housing 300. However, fuse 500 of the present invention is provided with reinforcing parts 350 connecting the wall parts of housing 300, so that housing 300 is strongly reinforced so that housing 300 does not expand and deform due to internal pressure P. Similarly, in fuse 500, reinforcing parts 360 formed by connecting and fixing upper and lower division parts 160 and 260 connect the wall parts, so that housing 300 is strongly reinforced so that housing 300 does not expand and deform due to internal pressure P.

[0040] 8 and 9 includes a reinforcing portion 350 located substantially in the center of the accommodation space 340 and a reinforcing portion 360 located on one side, but is not limited thereto, and may include only one of the reinforcing portion 350 or the reinforcing portion 360. However, by providing the reinforcing portion 350 spaced apart from the inner side surface 341 around the accommodation space 340, the weak portion of the accommodation space 340, i.e., the portion spaced apart from the inner side surface 341, can be reinforced by the reinforcing portion 350, and therefore the housing 300 can be more effectively prevented from expanding and deforming due to the internal pressure P. Also, the fuse 500 shown in FIGS. 8 and 9 includes three reinforcing portions (350, 360), but is not limited thereto, and may include any number of reinforcing portions, such as two, four or more. 8 and 9, the reinforcing portions (350, 360) connect the upper wall portion 110 and the lower wall portion 120, but this is not limited thereto, and each reinforcing portion (350, 360) may connect any two wall portions of the housing 300. Furthermore, in the fuse 500 shown in Figs. 8 and 9, the reinforcing portions (350, 360) are configured in a columnar shape connecting the wall portions, but this is not limited thereto, and the reinforcing portions may have any shape, such as a wall surface shape that separates the storage space 340 of the housing 300 into both sides.

[0041] Furthermore, because reinforcing portion 350 is provided so as to connect one housing split piece 100 and the other housing split piece 200 across each other, it can effectively prevent housing split pieces 100 and 200 from expanding in directions away from each other due to internal pressure P. Although housing 300 is composed of two split parts (housing split piece 100 and housing split piece 200), the present invention is not limited to this, and housing 300 may be composed of a single part that is molded as a whole, or housing 300 may be composed of three or more split parts.

[0042] Further, the reinforcing portion 350 is configured by connecting and fixing two divided portions (150, 250), but is not limited thereto, and the reinforcing portion 350 may be a single columnar body that crosses the accommodation space 340 and is molded as an integral part. In that case, the single reinforcement portion 350 that is molded as an integral part is provided on one housing split piece 100 of the housing 300, and the tip of the reinforcement portion 350 is connected and fixed to the other housing split piece 200 of the housing 300, thereby firmly fixing the housing split piece 100 and the housing split piece 200. Similarly, the reinforcing portion 360 is configured by connecting and fixing two divided portions (160, 260), but is not limited thereto, and the reinforcing portion 360 may be a single columnar body that crosses the accommodation space 340 and is molded as an integral part. Furthermore, the single reinforcing portion 350 is not limited to being integrally molded with one of the housing segments 100 of the housing 300, and the reinforcing portion 350 may be molded as a separate body from the housing 300. In that case, the reinforcing portion 350 is fixed to the housing 300 so as to penetrate the accommodation space 340, thereby reinforcing the housing 300.

[0043] Furthermore, since each divided portion (150, 250) constituting the reinforcing portion 350 is formed in each housing segment (100, 200), each divided portion can be formed at the same time as each housing segment is formed by a conventional method for forming each housing segment (e.g., injection molding, etc.).

[0044] 8 and 9, each reinforcing portion (350, 360) is provided at a distance from the fusing portion 420 so as not to come into contact with the fusing portion 420 of the fuse element 400. Therefore, each reinforcing portion (350, 360) does not thermally or physically affect the fusing portion 420, and the fusing characteristics of the fusing portion 420 are stable.

[0045] 9, the reinforcing portion 350 extends perpendicular to the extending direction of the fuse element 400, i.e., the direction parallel to the axis X connecting the terminal portions 410 on both sides. Therefore, the reinforcing portion 350 is less susceptible to the internal pressure P and thermal effects generated from the fusing portion 420, and the reinforcing portion 350 maintains its designed strength and can more effectively prevent the housing 300 from expanding and deforming due to the internal pressure P. Note that the reinforcing portion 350 extends perpendicular to the extending direction of the fuse element 400, i.e., the direction parallel to the axis X connecting the terminal portions 410 on both sides, but is not limited thereto, and may extend so as to be inclined at any angle with respect to the axis X. Compared to the case where the reinforcing portion 350 extends in a direction parallel to the axis X, the reinforcing portion 350 inclined at any angle with respect to the axis X is less susceptible to the internal pressure P and thermal effects generated from the fusing portion 420.

[0046] The fuse of the present invention is not limited to the above examples, and various modifications and combinations are possible within the scope of the claims and the scope of the embodiments, and these modifications and combinations are also included in the scope of the rights.

Claims

1. A fuse comprising a fuse element having a melting portion provided between a pair of terminal portions, and a housing for accommodating the fuse element, The housing includes a wall. The housing is provided with at least two reinforcing portions connecting the wall portions, A fuse, characterized in that the reinforcing portions are connected to each other at the wall portion by a base reinforcing body extending in the extension direction of the fuse element.

2. The housing includes one housing segment and another housing segment, 2. The fuse according to claim 1, wherein the reinforcing portion is provided across the housing split pieces on both sides.

3. The reinforcing portion includes one divided portion and another divided portion, the one divided portion is provided on the one housing divided piece, the other divided portion is provided on the other housing divided piece, 3. The fuse according to claim 2, wherein the one divided portion and the other divided portion are configured to be connectable and fixed to each other.

4. 4. The fuse according to claim 3, wherein a tip of the one split portion and a tip of the other split portion are connected and fixed by fitting together.

5. The reinforcing portion is provided on the one of the housing segments, 3. The fuse according to claim 2, wherein a tip of the reinforcing portion is connected and fixed to the other housing divided piece.

6. 6. The fuse according to claim 1, wherein the reinforcing portion is spaced apart from an inner side surface of the housing space.

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