A fuse structure suitable for short time withstand current

Abstract

The utility model discloses a kind of fuse structure suitable for short-time withstand current, including shell and the plug knife being set to both ends of shell, two conducting sheets are provided in shell and are formed with two plug-in cooperation plug knife, multiple fuses are provided in parallel between two conducting sheets, each fuse is composed of integrated structure by multiple interval arrangement fuse sheet, and including two connecting pieces respectively formed in two ends of multiple fuse sheet, and medium gap is formed between multiple fuse sheet along its length direction extension, extinguishing medium is filled in these medium gaps, so that arc can be rapidly divided, cooled and extinguished, fuse is welded on two conducting sheets by two connecting pieces, this structure design directly reduces welding frequency, simplifies operation process, fundamentally improves production efficiency, improves the consistency and reliability of product, ensure the safety breaking under short-time withstand current.

Description

Technical Field

[0001] This utility model relates to the field of low-voltage fuse technology, specifically to a fuse structure suitable for short-time withstand current. Background Technology

[0002] As a core component of circuit protection, the fuse's primary function is to disconnect the circuit when the current exceeds a specified value, either by melting the fusible element itself or through mechanical triggering, thereby protecting equipment and instruments from damage caused by overload or short-circuit currents. The basic structure of existing fuses generally includes a housing, a fusible element housed within the housing, and a contact blade located outside the housing and connected to the fusible element. For scenarios involving high-energy breaking arcs, the housing is also filled with an arc-extinguishing medium to assist in arc extinguishing and ensure the safety and stability of the breaking process. To effectively interrupt fault currents, current technologies typically employ a design that welds multiple identical fusible elements into a single fuse. The current is interrupted through the coordinated action of these multiple fusible elements. Traditional multi-fuse designs require individual spot welding of each fusible element, resulting in multiple spot welding processes. This is not only cumbersome but also increases the risk of breakage during welding, significantly reducing production efficiency. Utility Model Content

[0003] Therefore, the technical problem to be solved by this utility model is to overcome the problem that welding multiple identical molten elements inside the fuse in the prior art, with multiple molten elements corresponding to multiple spot welding processes, is cumbersome and reduces production efficiency.

[0004] To address the aforementioned problems, this utility model provides a fuse structure suitable for short-time withstand current, comprising a housing and inserts disposed at both ends of the housing, and a set of support members disposed within the housing and positioned in connection with the two inserts. Two conductive plates are disposed within the housing and respectively engage with the two inserts. The two conductive plates are fixed to the set of support members and electrically connected to the two inserts. Multiple fuse elements are arranged in a stacked manner between the two conductive plates. Each fuse element is composed of multiple spaced fuse pieces forming an integral structure, and includes two connecting pieces respectively formed at both ends of the multiple fuse pieces, and a dielectric gap extending along its length between the multiple fuse pieces. The fuse element is welded and fixed to the two conductive plates via the two connecting pieces.

[0005] As a preferred embodiment, multiple fusible links are arranged at intervals along the width direction of the fusible link and connected in parallel between two connecting links, which are bent and welded to two conductive links.

[0006] As a preferred embodiment, the housing is filled with an arc-extinguishing medium, which fills the medium gaps between the plurality of fused plates, and the two ends of the plurality of medium gaps are constrained by two connecting plates.

[0007] As a preferred embodiment, the fuse element is a planar sheet structure, which includes two fuse tabs arranged in parallel at intervals. Each fuse tab includes multiple fuse sub-units connected in series along its length direction, and adjacent fuse sub-units are connected by at least two fuse narrow sections.

[0008] As a preferred embodiment, the fusion strip is an integrally formed strip structure with multiple cutting end structures, which separate multiple fusion subunits to form two parallel fusion narrow sections.

[0009] As a preferred embodiment, the fuse subunit is composed of two integrally connected polygonal structural parts, and the two fuse slack sections between two adjacent fuse subunits are connected to the adjacent ends of the two polygonal structural parts.

[0010] As a preferred embodiment, the fusible narrow portion is a necked structure, and its cross-sectional area is smaller than that of the fusible subunit.

[0011] As a preferred embodiment, the support is a ceramic pad fixed to the inner side of the end plates at both ends of the housing; the ceramic pad is provided with a positioning hole, one end of the inserter is inserted into the positioning hole, and the end plates at both ends of the housing are provided with filling holes.

[0012] As a preferred embodiment, the conductive sheet is provided with multiple positioning grooves at intervals for positioning the fused body during spot welding.

[0013] As a preferred embodiment, the conductive sheet is provided with a plug hole that forms a plug-in engagement with one end of the insert; or, one end of the insert is formed with at least one plug block that mates with the plug hole, and the insert and the conductive sheet are fixedly connected by the engagement of the plug block and the plug hole.

[0014] Compared with the prior art, the technical solution of this utility model has the following advantages: 1. In the fuse structure provided by this utility model, the conductive sheet is connected to the insert and provides a connection position for the fuse body. The fuse body is formed by multiple spaced parallel fuse pieces connected to two connecting pieces to form an integrated structure. During installation, only the two connecting pieces at both ends of the fuse body need to be welded to the two conductive pieces to complete the fixation of all fuse pieces and conductive pieces. This structural design directly reduces the number of welding operations, simplifies the operation process, fundamentally improves production efficiency, and reduces the risk of fuse piece damage caused by multiple operations, thereby improving product consistency and reliability. The fuse body with this structural design forms multiple dielectric voids extending along the length direction through multiple spaced fuse pieces. These dielectric voids provide a uniform and stable space for filling the arc-extinguishing medium, which enables the arc to be quickly divided, cooled and extinguished, significantly improving the breaking capacity and arc-extinguishing performance, and ensuring safe breaking under short-time withstand current.

[0015] 2. In the fuse structure provided by this utility model, the two connecting pieces of the fuse body are bent and welded to the conductive piece, which increases the welding contact area between the fuse body and the conductive piece, making the welding point stronger, significantly improving the mechanical strength and electrical connection reliability. When used in conjunction with the positioning groove on the conductive piece, it can achieve fast and accurate one-time spot welding, greatly improving the convenience of assembly and production efficiency.

[0016] 3. In the fuse structure provided by this utility model, the fuse element is a strip structure formed in one piece by multiple fuse sub-units and fuse narrow sections. When a large current passes through for a short time, the series-connected sub-units can share the current load, reduce the Joule heat concentration in a single area, and improve the overall short-time withstand current limit of the fuse element. Each fuse narrow section is an independent current limiting point and arc initiation point. This design creates a double number of arc grids along the entire length of the fuse element, which can quickly divide the total arc energy into multiple small arcs, thereby forcibly limiting the peak value of the fault current and achieving excellent current limiting characteristics and rapid breaking. According to the fact that two parallel fuse narrow sections are formed between adjacent fuse sub-units, the two narrow sections share the current and breaking energy, avoiding excessive energy concentration at a single narrow point, which helps to reduce the arc energy intensity at a single point and extend the electrical life of the fuse.

[0017] 4. In the fuse structure provided by this utility model, the supporting component is a ceramic pad fixed to the inner side of the end plate at both ends of the housing. The molding process of this ceramic pad is more stable, the production cost is low, and it has excellent electrical insulation and arc erosion resistance. The ceramic pad is engaged with the insert through the positioning hole, which directly limits the installation position of the insert in the housing, avoids the insert from shifting or shaking, ensures the relative position of the insert, conductive sheet and fuse body is accurate, and ensures the stability of the current conduction path. The ceramic pad enables precise positioning and installation of the insert and conductive sheet and provides stable mechanical support. Attached Figure Description

[0018] To more clearly illustrate the specific embodiments of this utility model or the technical solutions in the prior art, the accompanying drawings used in the description of the specific embodiments or the prior art will be briefly introduced below.

[0019] Figure 1 A cross-sectional structural diagram of the fuse structure provided by this utility model; Figure 2 This is a schematic diagram of the internal structure of the fuse structure of this utility model; Figure 3 This is a schematic diagram of the structure of the fuse of this utility model; Figure 4 This is a schematic diagram of the separate structure of the support member, insert, and conductive sheet of this utility model; Figure 5 This is a schematic diagram of the installation structure of the support member, insert, and conductive sheet of this utility model; Explanation of reference numerals in the attached drawings: 1. Housing; 11. End plate; 2. Insert knife; 21. Insert block; 3. Conductive sheet; 31. Insert hole; 4. Ceramic pad; 5. Fuse element; 50. Fuse piece; 51. Connecting piece; 52. Medium gap; 53. Fuse subunit; 54. Fuse narrow section; 55. Cut-off structure; 6. Positioning groove; 7. Filling hole. Detailed Implementation

[0020] The technical solution of this utility model will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of this utility model. Based on the embodiments of this utility model, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this utility model.

[0021] In the description of this utility model, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this utility model and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0022] Example The following is a detailed description of this embodiment with reference to the accompanying drawings: This utility model provides, for example Figure 1-5The diagram illustrates a fuse structure suitable for short-time withstand current, comprising a housing 1 and inserts 2 disposed at both ends of the housing 1, and a set of support members disposed within the housing 1 and positioned in connection with the two inserts 2. The housing 1 contains two conductive plates 3 that respectively engage with the two inserts 2. The two conductive plates 3 are fixed to the set of support members and electrically connected to the two inserts 2. Between the two conductive plates 3, multiple fuse elements 5 are arranged in a stacked manner. Each fuse element 5 is composed of multiple spaced fuse pieces 50 forming an integral structure, and includes two connecting pieces 51 respectively formed at both ends of the multiple fuse pieces 50, and a dielectric gap 52 extending along its length between the multiple fuse pieces 50. The fuse element 5 is welded and fixed to the two conductive plates 3 via the two connecting pieces 51.

[0023] In the above embodiment, the housing is a cylindrical structure. A set of support members inside the housing 1 provides positioning and support for the insert 2 and the conductive sheet 3. The conductive sheet 3 provides a connection position for the fuse element. By arranging multiple fuse elements 5 in parallel between two conductive sheets 3 in a stacked manner, the total cross-sectional area of ​​the fuse element is doubled without significantly increasing the radial dimension of the fuse. The rated current that can be passed is thus greatly increased, improving the rated current of the fuse and meeting the needs of high-current electrical equipment. Specifically, the fuse element 5 is formed by connecting multiple spaced parallel fuse pieces 50 with two connecting pieces 51 to form an integrated structure. During installation, only the two connecting pieces of the fuse element 5 need to be welded to the two conductive sheets 3 to complete the installation of all fuse pieces. The fixing of 50 with conductive sheet 3 and the support component provide excellent mechanical support and insulation performance, ensuring the stable positioning of fuse 5 in the housing, improving the overall reliability and economy of the product. This structural design directly reduces the number of welding operations, simplifies the operation process, fundamentally improves production efficiency, and reduces the risk of fuse damage caused by multiple operations, improving product consistency and reliability. The fuse 5 with this structural design forms multiple dielectric voids extending along the length direction through multiple fuses arranged at intervals. These dielectric voids provide a uniform and stable space for filling the arc-extinguishing medium, enabling the arc to be quickly divided, cooled and extinguished, significantly improving the breaking capacity and arc-extinguishing performance, and ensuring safe breaking under short-time withstand current.

[0024] like Figure 3As shown, multiple fuse tabs 50 are arranged at intervals along the width direction of the fuse body 5 and connected in parallel between two connecting tabs 51. This layout achieves the maximum number of fuse tabs 50 connected in parallel within the limited cross-section of the housing 1, resulting in a larger total current-carrying cross-sectional area and increasing the rated current of the fuse. The parallel structure makes the current distribution among the fuse tabs 50 more uniform, avoiding single-point overheating. The housing 1 is filled with an arc-extinguishing medium, preferably quartz sand. The arc-extinguishing medium is filled in the medium gaps 52 between the multiple fuse tabs 50. The two ends of the multiple medium gaps 52 are constrained by the two connecting tabs 51. Combined with the heat dissipation channels of the medium gaps, good thermal management is achieved. The electric arc generated during breaking is introduced into these narrow gaps filled with arc-extinguishing medium, where it can be quickly broken, cooled, and extinguished. This structure significantly improves the arc voltage and effectively prevents arc crosstalk between fuse tabs, greatly improving the breaking capacity.

[0025] In a further preferred configuration, two connecting pieces 51 are bent and welded to two conductive pieces 3. Multiple positioning grooves 6 are spaced apart on the conductive pieces 3 for spot welding positioning of the fusible element 5. This structural configuration increases the welding contact area between the fusible element 5 and the conductive pieces 3, resulting in a stronger weld, significantly improved mechanical strength and electrical connection reliability. Furthermore, in conjunction with the positioning grooves on the conductive pieces 3, it enables rapid and precise one-time spot welding, enhancing assembly convenience and production efficiency.

[0026] The following is combined Figure 1-3 The specific settings for the fuse element and fuse tab are explained in detail: Multiple fuse elements 5 are planar structures and are arranged in two stacked groups between two conductive sheets 3. Each fuse element 5 includes two fuse pieces 50 connected in parallel between two connecting pieces 51. Each fuse piece 50 includes multiple fuse sub-units 53 connected in series along its length. Adjacent fuse sub-units 53 are connected by at least two fuse narrowing portions 54. More preferably, the fuse piece 50 is an integrally formed strip structure with multiple cutting structures 55. The cutting structures 55 separate the multiple fuse sub-units 53 to form two parallel fuse narrowing portions 54. The advantage of this design is that, since the fuse element 50 is formed in one piece by multiple fuse sub-units 53 and fuse narrow sections 54, when a large current passes through for a short time, the series-connected sub-units can share the current load, reduce the Joule heat concentration in a single area, and improve the overall short-time withstand current limit of the fuse element. Each fuse narrow section 54 is an independent current-limiting point and arc initiation point. This design creates twice the number of arc grids along the entire length of the fuse element, which can quickly divide the total arc energy into multiple small arcs, thereby forcibly limiting the peak value of the fault current and achieving excellent current-limiting characteristics and rapid breaking. Since two parallel fuse narrow sections 54 are formed between adjacent fuse sub-units 53, the two narrow sections share the current and breaking energy, avoiding excessive energy concentration at a single narrow point, which helps to reduce the arc energy intensity at a single point and extend the electrical life of the fuse.

[0027] In a further preferred configuration, the fuse subunit 53 is composed of two integrally connected polygonal structural parts, and two fuse-breaking narrow sections 54 between two adjacent fuse subunits 53 are connected to the adjacent ends of the two polygonal structural parts. The polygonal structural parts can be square, rhomboid, or other regular polygonal shapes, etc. The fuse-breaking narrow section 54 is a necked structure, and its cross-sectional area is smaller than that of the fuse subunit 53. With this structural configuration, the cutting-out structure 55 between adjacent fuse subunits 53 not only separates the parallel narrow sections but also forms a small heat dissipation gap. Combined with the arc-extinguishing medium inside the fuse housing, it improves the arc-extinguishing efficiency and prevents arc reignition. Because the fuse narrow sections are precisely separated by the cutting-out structure, the dimensions are highly consistent, ensuring that the current-carrying capacity and fusing threshold of each narrow section are consistent. This allows the current to be evenly distributed in the parallel fuse narrow sections, avoiding fusing time deviations caused by local overloads and improving the protection accuracy of the fuse.

[0028] The following is combined Figure 1 , Figure 4-5 The specific arrangement of the support components, conductive sheets, and inserts is explained in detail: The support component is a ceramic pad 4 fixed to the inner side of the end plates 11 at both ends of the housing 1. The molding process of this ceramic pad 4 is more stable, the production cost is low, and it has excellent electrical insulation and arc erosion resistance. The ceramic pad 4 is provided with positioning holes, and one end of the insert 2 is inserted into the positioning holes. The end plates 11 at both ends of the housing 1 are provided with filling holes 7, which are used to fill the housing with arc-extinguishing medium. With this structure, the ceramic pad 4 is inserted and matched with the insert 2 through the positioning holes, which directly limits the installation position of the insert 2 in the housing 1 and avoids the insert 2 from shifting or shaking. This ensures that the relative position of the insert 2, the conductive piece 3, and the fuse 5 is accurate and the current conduction path is stable. The ceramic pad 4 forms the core support skeleton inside the fuse, which achieves precise positioning and installation of the insert and the conductive piece and provides stable mechanical support.

[0029] In a further preferred embodiment, the conductive sheet 3 is provided with an insertion hole 31 that engages with one end of the inserter 2; or refer to Figure 5 As shown, one end of the insert 2 has two insertion blocks 21 formed to mate with the insertion holes 31. The conductive sheet 3 has two corresponding insertion holes 31. The insert 2 and the conductive sheet 3 are fixedly connected by the two insertion blocks and the two insertion holes. With this structure, the insert 2 is fixedly connected by inserting the insertion blocks into the insertion holes of the conductive sheet 3, avoiding loosening of the connection between the insert and the conductive sheet due to vibration and thermal expansion and contraction. This provides a long-term stable and reliable electrical connection. This connection structure increases the contact area between the insert and the conductive sheet, reduces contact resistance, reduces heat loss when current flows, avoids connection failure caused by local overheating, and ensures the stability of circuit conduction.

[0030] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A fuse structure suitable for short-time withstand current, comprising a housing (1) and inserts (2) disposed at both ends of the housing (1), characterized in that: The housing (1) is provided with two conductive sheets (3) that are plugged into the two inserts (2). Between the two conductive sheets (3) are multiple fuses (5) arranged in a stacked manner. Each fuse (5) is composed of multiple spaced fuses (50) forming an integral structure, and includes two connecting pieces (51) respectively formed at both ends of the multiple fuses (50), and a medium gap (52) extending along its length and formed between the multiple fuses (50). The fuse (5) is welded to the two conductive sheets (3) through the two connecting pieces (51).

2. The fuse structure according to claim 1, characterized in that: Multiple fusible pieces (50) are arranged at intervals along the width direction of the fusible body (5) and are connected in parallel between two connecting pieces (51). The two connecting pieces (51) are bent and welded to two conductive pieces (3).

3. The fuse structure according to claim 2, characterized in that: The housing (1) is filled with an arc-extinguishing medium, which fills the medium gaps (52) between the plurality of fused plates (50), and the two ends of the plurality of medium gaps (52) are constrained by two connecting plates (51).

4. The fuse structure according to any one of claims 1-3, characterized in that: The fuse element (5) includes two fuse tabs (50) arranged in parallel at intervals. Each fuse tab (50) includes multiple fuse sub-units (53) connected in series along its length. Adjacent fuse sub-units (53) are connected by at least two fuse slits (54).

5. The fuse structure according to claim 4, characterized in that: The fusion strip (50) is an integrally formed strip structure with multiple cut-out structures (55). The cut-out structures (55) are separated between multiple fuse sub-units (53) to form two parallel fuse narrow sections (54).

6. The fuse structure according to claim 5, characterized in that: The fuse subunit (53) is composed of two integrally connected polygonal structural parts, and two fuse stencils (54) between two adjacent fuse subunits (53) are connected to the adjacent ends of the two polygonal structural parts. The fuse stencils (54) are necked structures, and their cross-sectional area is smaller than that of the fuse subunit (53).

7. The fuse structure according to claim 1, characterized in that: The housing (1) is provided with a set of support members that form a positioning connection with the two inserts (2). Two conductive plates (3) are fixedly connected to the set of support members and electrically connected to the two inserts (2) respectively.

8. The fuse structure according to claim 7, characterized in that: A set of support components includes two ceramic pads (4) fixed to the inner side of the end plates (11) at both ends of the housing (1); the ceramic pads (4) are provided with positioning holes, one end of the inserter (2) is inserted into the positioning holes, and the end plates (11) at both ends of the housing (1) are provided with filling holes (7).

9. The fuse structure according to claim 8, characterized in that: The conductive sheet (3) is provided with multiple positioning grooves (6) at intervals for spot welding positioning of the fuse (5).

10. The fuse structure according to claim 8, characterized in that: The conductive sheet (3) is provided with a plug hole (31) that is plugged into one end of the insert (2); or, one end of the insert (2) is formed with at least one plug block (21) that is plugged into the plug hole (31), and the insert (2) and the conductive sheet (3) are fixedly connected by the plug block and the plug hole.

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