fuse

Abstract

To provide a fuse which can deal with high voltage / high current while maintaining a dimension of a casing.SOLUTION: A fuse 900 includes a casing 100, terminal parts 300 at both sides, and a fuse element 200 housed in the casing 100. The fuse element 200 has a wave shape including trough parts 220 and crest parts 230 and has fused parts 240. A tip 231 of the crest part 230 is provided with a cutout part 235 formed by cutting out an end 234.SELECTED DRAWING: Figure 1

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 inserted and 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 a type in which a fuse element is inserted and held inside a cylindrical casing. In recent years, there has been a demand for fuses that can handle high voltages and high currents, and the number of fusing parts may be increased or the overall length of the fuse element may be increased. However, when the configuration of the fuse element is made more complex by increasing the number of fusing parts or increasing the overall length of the fuse element, the width, length, height, etc. of the fuse element tend to become larger overall. This has led to a problem in that the casing that houses the fuse element also becomes larger. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2012-43573 DISCLOSURE OF THEINVENTION [Problem to be solved by the invention]

[0005] In view of the above problems, the present invention provides a fuse that can withstand high voltages and high currents while maintaining the dimensions of the casing. [Means for solving the problem]

[0006] The fuse of the present invention comprises a casing, terminal portions on both sides, and a fuse element housed within the casing, the fuse element having a wave-like shape with valleys and peaks, a melting portion, and a notch at the tip of the peak where the end is cut out.

[0007] According to the above features, even if the fuse element is made complex in structure to handle high voltages and high currents, the cutouts ensure that the ends of the crests of the fuse element do not interfere with the opening or inner surface of the casing and prevent the fuse element from being inserted and accommodated. As a result, there is no need to make the casing larger, and the dimensions of the casing can be maintained.

[0008] Furthermore, the fuse of the present invention is characterized in that the melting portions are aligned along a center line connecting the connection ends on both sides of the fuse element.

[0009] According to the above feature, the fusion portion is positioned at a position away from the inner surface of the casing, so that the arc generated at the fusion portion is efficiently extinguished by the internal arc-extinguishing material, etc., at a position away from the inner surface of the casing.

[0010] Furthermore, the fuse of the present invention is characterized in that the melting portion is provided in the valley portion of the fuse element.

[0011] According to the above feature, since the fusing portion is provided in the valley portion, it is located at a position away from the inner surface of the casing, so that the arc generated at the fusing portion is efficiently extinguished by the internal arc-extinguishing material at a position away from the inner surface of the casing.

[0012] Furthermore, the fuse of the present invention is characterized in that the ridge is provided so as to protrude only on one side from a center line connecting both connection ends of the fuse element.

[0013] According to the above feature, the fuse element can be easily inserted through the opening in the casing. Effect of the Invention

[0014] As described above, the fuse of the present invention can handle high voltages and high currents while maintaining the same casing dimensions. [Brief description of the drawings]

[0015] [Figure 1] 1 is an exploded perspective view of a fuse according to the present invention; [Diagram 2] 1A is a plan view of the fuse element, FIG. 1B is a side view of the fuse element, and FIG. 1C is a front view of the fuse element. [Diagram 3] FIG. 2 is a general perspective view of an assembled fuse. [Figure 4] FIG. 2(a) is a side view of the fuse, and FIG. 2(b) is a plan view of the fuse. [Diagram 5] 4A is a cross-sectional view taken along line AA in FIG. 4, and FIG. [Explanation of symbols]

[0016] 100 Casing 200 Fuse Element 220 Valley 230 Yamabe 231 Tip 234 End 235 Notch 240 Melting point 300 Terminal section 900 Fuse DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] Hereinafter, an embodiment of the present invention will be described with reference to the drawings. Note that the shapes and materials of the components of the fuse in the embodiment described below are merely examples and are not limited to these. Note that the "vertical direction" described in this specification refers to the direction perpendicular to the longitudinal direction of the fuse element.

[0018] First, a fuse 900 according to the present invention is shown in Fig. 1. Fig. 1 is an exploded perspective view of the fuse 900.

[0019] As shown in FIG. 1, the fuse 900 includes a casing 100, a fuse element 200 housed in the casing 100, and terminals 300 connected to both ends of the fuse element 200. The casing 100 has a cylindrical shape with openings 120 at both ends 110, and is configured to be able to house the fuse element 200 in an internal housing space 130. The casing 100 can be manufactured from various materials such as ceramics and synthetic resins. The casing 100 is not limited to a cylindrical shape with a circular cross section, and may have any shape, such as a box shape with a square cross section, as long as it has an opening 120 into which the fuse element 200 can be inserted.

[0020] Moreover, the terminal portion 300 is made of metal, and includes a cap portion 310 that fits onto the end portion 110 of the casing 100 from the outside, and a flat connection portion 320 that is connected to an external electric circuit. When the cap portion 310 is fitted onto the end portion 110 of the casing 100, a side surface 311 of the cap portion 310 can close the opening portion 120 of the casing 100.

[0021] Next, the configuration of the fuse element 200 will be described in detail with reference to Fig. 2. Fig. 2(a) is a plan view of the fuse element 200, Fig. 2(b) is a side view of the fuse element 200, and Fig. 2(c) is a front view of the fuse element 200.

[0022] As shown in FIG. 2, the fuse element 200 is formed in an elongated shape from a single thin metal plate, and includes a pair of flat connection ends 210, a valley portion 220 and a peak portion 230 between the connection ends 210, and is wavy due to the valley portion 220 and the peak portion 230. The valley portion 220 and the peak portion 230 are formed by bending a single thin metal plate into a wave shape. The valley portion 220 has a flat surface and is parallel to the center line P connecting the connection ends 210 on both sides. Each valley portion 220 is provided with a fusing portion 240, and the fusing portion 240 is formed by opening a plurality of small holes 221. Each fusing portion 240 is aligned along the center line P connecting the connection ends 210 on both sides.

[0023] Further, between the valley portions 220, peak portions 230 are provided that protrude from the valley portions 220 in a substantially U-shape in side view. The peak portions 230 include a tip portion 231 and side surfaces 232 that extend from the tip portion 231 to both sides and are connected to the valley portions 220. As shown in Fig. 2(b) , the peak portions 230 protrude only to one side (the upper side in the drawing) of a center line P that connects the connection end portions 210 on both sides in side view.

[0024] Furthermore, at the tip 231 of the peak 230, a notch 235 is provided by cutting out an end 234 of the tip 231. Specifically, as shown in Fig. 2(a) , in a plan view, the end 234 of the peak 230 is located on both sides of the center line P, and further, the end 234 is cut out in a substantially U-shape toward the center line P side, i.e., toward the inside, and the cut-out portion serves as the notch 235.

[0025] As shown in Fig. 2, the fusing portion 240 is provided only in the valley portion 220, and is not provided in the peak portion 230. As shown in Fig. 2(b), the peak portion 230 protrudes only on one side (upper side in the drawing) of the center line P connecting the connection end portions 210 on both sides in a side view, but is not limited to this, and the peak portion 230 may protrude on both sides (upper side and lower side in the drawing) of the center line P. As shown in Fig. 2(a), the notch portion 235 is provided in the end portions 234 on both sides of the tip portion 231 of the peak portion 230, but is not limited to this, and the notch portion 235 may be provided only on the end portion 234 on one side of the tip portion 231.

[0026] 2, the fuse element 200 includes a plurality of melting portions 240. Furthermore, since the fuse element 200 has a wave shape, the overall length is long, in other words, the overall length of the path of the current flowing through the fuse element 200 is long. Therefore, the fuse 900 of the present invention is capable of handling high voltages and high currents. Note that the number of melting portions 240 of the fuse element 200 and the number of waves consisting of the valleys 220 and the peaks 230 may be any number other than those shown in FIG. 2.

[0027] 1, when assembling the fuse 900, the fuse element 200 is inserted into the casing 100 through one opening 120 of the casing 100 and housed therein. Next, the terminal parts 300 are attached to the ends 110 on both sides of the casing 100, and the opening 120 is closed, completing the assembly of the fuse 900 as shown in Figures 3 to 5. Note that Figure 3 is an overall perspective view of the fuse 900, Figure 4(a) is a side view of the fuse 900, Figure 4(b) is a plan view of the fuse 900, Figure 5(a) is a cross-sectional view taken along line A-A in Figure 4, and Figure 5(b) is a cross-sectional view taken along line B-B in Figure 4.

[0028] As shown in FIG. 3 to FIG. 5, in the assembled fuse 900, the connection ends 210 on both sides of the fuse element 200 are electrically connected to the terminal parts 300. The fuse 900 is mounted by electrically connecting the connection parts 320 of the terminal parts 300 to an electric circuit. The current flowing in the electric circuit flows from one terminal part 300 to the other terminal part 300 via the fuse element 200. When an unintended overcurrent flows in the electric circuit, the melting part 240 of the fuse element 200 housed in the casing 100 heats up and melts, thereby cutting off the overcurrent. Granular arc-extinguishing material is enclosed inside the casing 100, and the fuse element 200 is surrounded by the arc-extinguishing material. Therefore, the arc generated when the melting part 240 melts is quickly extinguished by the surrounding arc-extinguishing material.

[0029] 5, the vertical cross section of the cylindrical casing 100 is circular. The fuse element 200 is accommodated in the accommodation space 130 of the casing 100 so that the ridges 230 of the fuse element 200 contact or are very close to the circular inner surface 101 of the casing 100. In this manner, by bending the ridges 230 of the fuse element 200 until they contact or are very close to the inner surface 101 of the casing 100, the ridges 230 can be bent upward to their limit, and as a result, the overall length of the fuse element 200 can be increased.

[0030] Furthermore, even if the peaks 230 of the fuse element 200 are bent until they come into contact with or are extremely close to the inner surface 101 of the casing 100, the end 234 of the tip 231 of the peaks 230 is provided with the notch 235, so that when the fuse element 200 is inserted into the casing 100 through the opening 120 and accommodated therein, the end 234 of the peaks 230 does not interfere with the opening 120 or the inner surface 101 of the casing 100 to prevent the insertion and accommodation of the fuse element 200. Thus, according to the fuse 900 of the present invention, even if the configuration of the fuse element is made complex to accommodate high voltages and high currents, interference with the casing 100 can be prevented, and as a result, there is no need to enlarge the casing 100, and the dimensions of the casing 100 can be maintained.

[0031] 5(b), since the fusion portion 240 is provided in the valley portion 220, it is disposed at a position away from the inner surface 101 of the casing 100. Therefore, the arc generated at the fusion portion 240 is efficiently extinguished at a position away from the inner surface 101 of the casing 100 by the internal arc-extinguishing material or the like.

[0032] Furthermore, since each fusing portion 240 is aligned along the center line P connecting the connection end portions 210 on both sides, each fusing portion 240 is effectively arranged at a position away from the inner surface 101 of the casing 100. Therefore, the arc generated in the fusing portion 240 is efficiently extinguished by the internal arc extinguishing material or the like at a position away from the inner surface 101 of the casing 100. Note that each fusing portion 240 is aligned in parallel along the center line P connecting the connection end portions 210 on both sides, but this is not limited thereto, and each fusing portion 240 may be arranged at any position and in any posture. Also, although the fusing portion 240 is provided only in the valley portion 220 and not in the peak portion 230, this is not limited thereto, and the fusing portion 240 may be provided at any position of the fuse element 200, such as the valley portion 220 or the peak portion 230.

[0033] Furthermore, as shown in FIG. 5(b), the ridge portion 230 protrudes only on one side (the upper side in the drawing) of the center line P connecting the connection ends 210 on both sides, making it easy to insert the fuse element 200 through the opening 120 of the casing 100.

[0034] The fuse element 200 is composed of one thin metal plate, but is not limited thereto, and may be composed of a plurality of metal plates. The fuse 900 includes one fuse element 200, but is not limited thereto, and may be composed of a plurality of fuse elements 200. The fuse element 200 is provided with a plurality of small holes to form the fusion portion 240, but is not limited thereto, and may be formed, for example, by locally thinning the thickness of the valley portion 220 to form the fusion portion, or by depositing a low melting point metal such as tin, lead, silver, nickel, or an alloy thereof in the narrow portion of the valley portion 220 to form the fusion portion. A material such as silicon may be attached to the U-shaped bent portion on the back side of the peak portion 230.

[0035] Furthermore, 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 rights.

Claims

1. A casing, terminal portions on both sides, a fuse element housed within the casing, The fuse element has a wave shape with valleys and peaks and has a melting portion, A fuse characterized in that a notch is provided at the tip of the mountain portion by cutting out an end portion.

2. 2. The fuse of claim 1, wherein the melting portion is aligned along a center line connecting opposite connection ends of the fuse element.

3. 3. The fuse according to claim 1, wherein the melting portion is provided in the valley portion of the fuse element.

4. 3. The fuse according to claim 1, wherein the ridge is provided so as to protrude only on one side from a center line connecting both connection ends of the fuse element.

5. 4. The fuse according to claim 3, wherein the ridge portion is provided so as to protrude only on one side from a center line connecting both connection ends of the fuse element.

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