Fuse

Abstract

The utility model provides a fuse, which comprises an insulated tube body with two open ends, a fusible body and end caps matched with the two ends of the tube body, the bottom of each end cap protrudes towards the outer side of the tube body and is provided with a protruding part, the protruding parts form accommodating grooves capable of accommodating soldering tin in the end caps, and the two ends of the fusible body are respectively inserted into the accommodating grooves and are coated by the molten soldering tin. And the two ends of the fusible body are welded between the two end caps. The fuse is firm in structure and not easy to loosen, and reliability and safety of the fuse can be improved.

Description

Technical Field

[0001] The utility model relates to the technical field of circuit protection, and more particularly to a fuse. Background Art

[0002] A fuse, also known as a fuse cutout, is an electrical component installed in an electrical circuit to ensure safe operation. The function of a fuse is to melt itself when the current rises abnormally high and for a certain period of time, cutting off the current and thus protecting the circuit.

[0003] In the prior art, a common fuse structure can be as follows: Figure 1 As shown, it generally comprises: an insulated tube body 10' with open ends, two end caps 1', and a fusible element 3'. The tube body 10' is also filled with an arc-extinguishing filler 4'. During production, solder 2' is typically pre-placed within the end caps 1'. The fusible element 3' is positioned diagonally within the tube body 10', with both ends of the fusible element 3' extending out of the tube body 10' and being bent and fixed to the outer wall of the tube body 10'. The end caps 1' are then placed over the open ends of the tube body 10', and the solder 2' is heated to melt. This secures the connection between the tube body 10', the end caps 1', and the fusible element 3'. At this point, the solder 2' exists in the gap between the tube body 10' and the end caps 1'.

[0004] For existing fuse structures, the end cap is flat-bottomed. Regardless of whether the fusible element is placed in a straight line or in the diagonal arrangement mentioned above in the insulating tube, in order to ensure effective welding (avoiding the occurrence of cold welding and false welding), improve welding reliability, and ensure that there is no displacement during welding, it is necessary to increase the amount of solder, which increases the cost of consumables. Figure 1In the conventional structure shown (where the fusible element is diagonally aligned), when the fusible element and the end cap are assembled and welded, since the solder 2' is pre-set within the end cap 1', it is heated and melted for welding after the fuse is assembled. The flow of the solder 2' during the heat-melting process is uncontrolled. Due to the pre-set amount of solder 2' or the uncontrolled flow, some of the solder 2' may melt and overflow from the gap between the tube body 10' and the end cap 1', resulting in solder overflow, waste, and affecting normal assembly. Furthermore, in addition to the solder 2' used for connection, the gap between the tube body 10' and the end cap 1' may also contain the fusible element 3' bent and fixed to the outer wall of the tube body 10'. When the fusible element 3' melts, the high temperature may cause the solder 2' in the gap between the outer wall and the inner wall of the end cap 1' to also melt, causing the tube body 10' and the end cap 1' to loosen or even fall off during use, posing a risk to circuit safety. When the fuse is working, the fusible element 3' heats up, and the solder 2' melts due to the heat of the fusible element 3' and overflows from the gap between the tube body 10' and the end cap 1'. The overflowing solder will drip or flow onto the circuit board, affecting the external environment, causing contamination of the circuit board and even causing a short circuit risk. Utility Model Content

[0005] The purpose of the utility model is to provide a fuse with a firm structure that is not easy to loosen, which reduces the amount of solder used while ensuring reliability and safety.

[0006] To achieve the above purpose, the solution of the utility model is:

[0007] A fuse comprises an insulated tube body with open ends, a fusible element, and end caps fitted onto the ends of the tube body. The end caps have a raised portion protruding from the bottom surface toward the outside of the tube body. The raised portion forms a trough within the end caps for accommodating solder. The ends of the fusible element are respectively inserted into the troughs and coated with molten solder, so that the ends of the fusible element are welded between the end caps.

[0008] Furthermore, the accommodating groove is provided at the center of the inner wall of the bottom surface of the end cap, and the fusible body is vertically located between the two end caps.

[0009] Furthermore, the receiving groove is formed in a square, cylindrical or hemispherical shape.

[0010] Furthermore, the end cap and the tube body are fixed by interference fit.

[0011] Furthermore, the tube body is filled with arc-extinguishing filler.

[0012] After adopting the above scheme, the utility model inserts the two ends of the fusible element into the solder in the receiving grooves of the end caps, thereby ensuring a secure weld that is not easily loosened and preventing cold solder joints. The temperature rise of the fusible element during use does not affect the fixed connection between the end caps and the tube body, preventing the end caps from loosening and falling off. The solder is set in the receiving groove and does not leak out of the space formed by the end caps and the tube body, preventing tin overflow. Because the solder is confined to the receiving groove, a reliable electrical and mechanical connection can be achieved with a small amount of solder, saving costs. Therefore, the fuse of the utility model has the advantages of reducing costs and increasing efficiency, as well as a solid, reliable, and safe structure. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 This is a structural cross-sectional view of an existing fuse;

[0014] Figure 2 It is a cross-sectional view of the utility model;

[0015] Figure 3 It is a top view of the end cap of the utility model;

[0016] Figure 4 It is a cross-sectional view of the end cap of the utility model.

[0017] Description of Figure Numbers:

[0018] Existing technology: 10' tube body; 1' end cap; 2' solder; 3' fusible element; 4' arc-extinguishing filler;

[0019] The utility model comprises: 10 a tube body; 1 an end cap; 110 a raised portion; 11 an accommodating groove; 2 solder; 3 a fusible body; and 4 an arc-extinguishing filler. DETAILED DESCRIPTION

[0020] In order to further explain the technical solution of the present invention, the present invention will be described in detail below through specific embodiments.

[0021] See Figure 2 The utility model discloses a fuse, comprising a tube body 10 with both ends open and insulated, a fusible element 3, and end caps 1 fitted on both ends of the tube body 10. The end caps 1 can be fixedly mounted on both ends of the tube body 10, respectively, and the end caps 1 and the tube body 10 can be fixed by interference fit. The tube body 10 can be a cylindrical tube or a square tube, etc. The end cap 1 can be a copper cap. The end cap 1 can include a bottom surface and a ring side surface integrally formed on the periphery of the bottom surface. The shape of the end cap corresponds to the shape of the tube body. The end cap in this embodiment is cylindrical. The fusible element 3 is mounted in the tube body 10 and its two ends are welded to the end caps 1. The tube body 10 can also be filled with arc-extinguishing filler 4, such as quartz sand.

[0022] Combine Figures 2 to 4As shown, the main improvement of the present invention is that a protrusion 110 is provided on the bottom surface of the end cap 1 protruding toward the outside of the tube body 10. The protrusion 110 forms a receiving groove 11 in the end cap 1 for receiving the solder 2. The two ends of the fusible body 3 are respectively inserted into the receiving groove 11 and coated by the molten solder, so that the two ends of the fusible body 3 are welded between the two end caps 1. During welding, the receiving groove 11 can be pre-filled with solder 2 (such as solder paste), and the two ends of the fusible body 3 are respectively inserted into the receiving groove 11 of the two end caps 1. The solder 2 in the receiving groove 11 melts after the end caps are heated, thereby coating the fusible body 3, so that the fusible body 3 is welded to the receiving groove 11 of the two end caps 1 through the solder 2 and is located between the two end caps 1.

[0023] Further reading Figure 3 、 Figure 4 In this embodiment, the receiving groove 11 is provided in the center of the bottom surface of the end cap 1, and the fusible body 3 is vertically located between the end caps 1. The receiving groove 11 can be formed into a square, cylindrical or hemispherical groove body according to the shape of the protrusion. In this embodiment, the receiving groove 11 forms a cylindrical cavity.

[0024] According to the above structure, the utility model has at least the following technical effects:

[0025] 1. The solder 2 is pre-filled in the receiving groove 11. After being heated and melted, it only fills the receiving groove 11. Therefore, the shape of the solder 2 is fixed to the shape of the receiving groove 11. When welding the fusible element 3, the two ends of the fusible element 3 are inserted into the solder 2 in the receiving groove 11 to achieve effective contact and welding, avoiding cold welding or false welding. The connection between the fusible element 3 and the end cap 1 is firm. The fusible element 3 is fixed between the two end caps 1 and will not shake or move. The fuse can achieve reliable electrical connection and firm mechanical connection.

[0026] 2. Since the accommodating groove 11 is provided to accommodate the solder 2, when the solder 2 is heated and melted, for example, when the fusible element 3 is welded to the end cap 1 or when the fusible element 3 is heated, the solder 2 melts but does not overflow from the accommodating groove 11. Even if a small amount overflows, it protrudes outside the accommodating groove 11 and is located on the inner wall of the bottom surface of the end cap. This does not cause the situation mentioned in the background art where the solder 2' overflows along the gap between the tube body 10' and the end cap 1' and adheres to the outer tube wall of the tube body 10' or even drips onto the circuit board, thereby improving the safety of the fuse.

[0027] 3. The two ends of the fusible element 3 are directly inserted into the accommodating groove 11. There is no need to extend the two ends of the fusible element 3 out of the tube body 10 and bend and fix them on the outer wall of the tube body 10 as in the background art. This can prevent the fusible element 3 from being damaged at the bend, thereby ensuring the safety and reliability of the fuse. At the same time, it will not cause the situation in the background art where the bent sections of the two ends of the fusible element 3' heat up and melt the solder 2', resulting in an unstable connection between the end cap 1' and the tube body 10' and causing the end cap 1' to fall off, thereby making the fuse have a firm structure and not easy to loosen.

[0028] 4. Based on point 3, since there is no need to set the bending sections at both ends of the fusible element 3' as in the background art, the length of the fusible element 3 required for manufacturing fuses of the same specifications becomes shorter, saving costs.

[0029] 5. Based on point 3, since the heating of the fusible element 3 of the present invention will no longer affect the connection stability between the end cap 1 and the tube body 10, the fuse of the present invention can allow a larger current to pass through when other conditions are the same, compared with the prior art, with the help of structural improvements, so that the fuse has a larger current rating.

[0030] 6. The solder 2 of the present invention is only arranged in the accommodating groove 11, and its function is only to weld the fusible body 3 and the end cap 1. Compared with the background technology, it is only necessary to set a certain amount of solder at the midpoint of the accommodating groove 11, and the end of the fusible body 3 will smoothly contact the solder 2 and ensure the reliability of welding. The structure is simple, which can greatly reduce the amount of solder used and achieve the effect of reducing material costs.

[0031] The above is only an embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent replacements and improvements made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A fuse comprising an insulated tube with open ends, a fusible element, and end caps fitted onto the ends of the tube, characterized in that: The bottom surface of the end cap is provided with a protrusion protruding toward the outside of the tube body. The protrusion forms a accommodating groove inside the end cap for accommodating solder. The two ends of the fusible body are respectively inserted into the accommodating groove and covered by the molten solder, so that the two ends of the fusible body are welded between the two end caps.

2. A fuse according to claim 1, characterized in that: The accommodating groove is arranged at the center of the inner wall of the bottom surface of the end cap, and the fusible body is vertically located between the two end caps.

3. A fuse according to claim 2, characterized in that: The receiving groove is formed in a square, cylindrical or hemispherical shape.

4. A fuse according to any one of claims 1 to 3, characterized in that: The end cap and the tube body are fixed by interference fit.

5. A fuse according to claim 4, characterized in that: The tube body is also filled with arc-extinguishing filler.

Images