Direct-current current-limiting fuse with cooling system
By introducing a cooling system and a special melt layout into the DC current limiting fuse, the problem of arcing time lag in the short circuit situation of traditional fuses is solved, and the dual protection effect is achieved under large rated current and short circuit situations is achieved.
Patent Information
- Application Number
- CN202420213795.3
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- Filing Date
- 2024-01-29
- Publication Date
- 2025-02-11
- Estimated Expiration
- 2034-01-29
AI Technical Summary
Traditional fuses have high temperature rise tolerance requirements when facing large rated currents, but in short-circuit conditions, the arcing time lags, and the short-circuit current energy is high during the current limiting period, resulting in equipment damage and inability to effectively protect.
Design a DC current limiting fuse with cooling system, the melt is arranged in the sealing space between the inner insulating tube and the outer insulating tube. The inner cavity of the inner insulating tube is forced to cool and cool through a fan to ensure that the fuse starts quickly when the short circuit is shorted. Arc breaks.
It achieves the satisfaction of temperature rise withstand requirements when the rated current is large, and at the same time, it responds quickly in short circuit situations, breaks quickly, avoids equipment damage, and improves the protection effect.
Smart Images
Figure CN222462807U_ABST
Abstract
Description
Technical Field
[0001] The utility model relates to the technical field of fuses, in particular to a DC current limiting fuse with a cooling system. Background Art
[0002] A fuse is an electrical device that uses the heat generated by itself to melt the fuse and disconnect the circuit when the current exceeds the specified value. When the line load requires a large power, the required load current will be relatively large, which means that the rated current of the traditional fuse that protects the line will have higher requirements. However, under such conditions, when a short circuit occurs, the short-circuit current will have a high rise rate and short-circuit current peak.
[0003] In order to meet the requirement that the temperature rise does not exceed 70K at the rated current or the required withstand impulse current, traditional fuses will design the fuse element to reduce the fuse resistance, reduce the thermal power of the fuse, and thus reduce the temperature rise; however, when facing a short-circuit current, since the fuse element is designed to meet the temperature rise withstand condition, the fuse resistance is small, which will cause the fuse arcing time to lag and the arcing time to be too long. The energy generated by the short-circuit current during the current limiting period is large, which will cause great damage to the load or equipment that needs to be protected, and will not play a protective role. Utility Model Content
[0004] The utility model aims to solve the problems in the prior art and proposes a DC current limiting fuse which can not only meet the temperature rise tolerance requirements at large rated currents, but also can act quickly and disconnect quickly when a short circuit occurs.
[0005] In order to achieve the above purpose, the utility model adopts the following technical solutions:
[0006] A DC current limiting fuse with a cooling system, comprising:
[0007] Inner insulation tube;
[0008] An outer insulating tube, which is arranged around the outer periphery of the inner insulating tube;
[0009] A plurality of melts, each melt is arranged between the inner insulating tube and the outer insulating tube, and is arranged at intervals around the inner insulating tube;
[0010] and a fan, which is arranged at one end of the inner insulating tube to blow air to the inner side of the inner insulating tube.
[0011] Furthermore, it also includes a first copper pole and a second copper pole, the first copper pole is arranged at one end of the inner insulating tube and the outer insulating tube, and the second copper pole is arranged at the other end of the inner insulating tube and the outer insulating tube, so that a closed space is formed between the inner insulating tube and the outer insulating tube, and the closed space is filled with quartz sand. A through hole is provided in the middle of the first copper pole and the second copper pole, and the through hole coincides with the center line of the inner insulating tube. The two ends of each melt are fixedly connected to the first copper pole and the second copper pole respectively.
[0012] Furthermore, the first copper pole and the second copper pole are provided with fixing grooves on one side close to the inner insulating tube, and the two end surfaces of the inner insulating tube can be respectively inserted into the fixing grooves of the first copper pole and the second copper pole, and sealing gaskets are provided inside the fixing grooves to seal between the copper poles and the inner insulating tube.
[0013] Furthermore, a first through hole is opened on one side of the first copper pole and the second copper pole, the first through hole is a countersunk hole, and first threaded holes are provided on both end surfaces of the inner insulating tube. The first through hole is adapted to the first threaded hole so that the first copper pole and the second copper pole are respectively fixed to the two end surfaces of the inner insulating tube.
[0014] Furthermore, an annular groove is provided on the outside of the first copper pole and the second copper pole, and a sealing ring is provided inside the annular groove. The sealing ring is located between the copper pole and the outer insulating tube to seal the copper pole and the outer insulating tube.
[0015] Furthermore, a second threaded hole is provided on the outside of the first copper pole and the second copper pole, and a second through hole is provided on the outer wall of the two ends of the outer insulating tube. The second through hole is a countersunk hole, and the second through hole is adapted to the second threaded hole so that the first copper pole and the second copper pole are respectively fixed to the two ends of the outer insulating tube.
[0016] Furthermore, it also includes a first connecting row and a second connecting row, which are respectively arranged on one side of the first copper pole and the second copper pole, the first connecting row and the first copper pole are fixedly connected by bolts, and the second connecting row and the second copper pole are fixedly connected by bolts, and ventilation holes are provided on one side of the first connecting row and the second connecting row, and the ventilation holes coincide with the center line of the inner insulating tube.
[0017] Furthermore, a mounting plate is provided on one side of the first connecting row, and a countersunk hole is provided on one side of the mounting plate so that the first connecting row and the mounting plate are fixed by bolts. A third threaded hole is provided on the side of the mounting plate away from the first connecting row, and the fan is fixedly connected to the third threaded hole of the mounting plate by bolts. The mounting plate is made of insulating material, and a circular hole is provided in the middle of the mounting plate. The diameter of the circular hole is consistent with the inner diameter of the inner insulating tube, and the center lines of the fan, the circular hole and the inner insulating tube coincide.
[0018] Furthermore, an annular ring is provided on one side of the mounting plate close to the first connection row, and the annular ring can be inserted into the ventilation hole of the first connection row and the through hole of the first copper pole, and the inner wall of the annular ring is connected to the inner wall of the circular hole.
[0019] Furthermore, each melt is provided with a plurality of narrow band portions at equal intervals along the length direction, and a plurality of square holes are provided at equal intervals along the width direction of the melt at the narrow band portions. Both ends of each melt are L-shaped and are respectively welded to the first copper pole and the second copper pole.
[0020] The beneficial effects of the utility model are:
[0021] The DC current limiting fuse with a cooling system in the utility model sets the fuse in a sealed space between an inner insulating tube and an outer insulating tube. The inner cavity of the inner insulating tube can be forced to cool by a fan to dissipate heat, thereby ensuring that the fuse has excellent tolerance characteristics. At the same time, the fuse will immediately start an arc after the short-circuit current meets the triggering conditions, and perform a current limiting action, thereby having a fast short-circuit response characteristic. The overall structure of the fuse is simple, and the internal space of the fuse is fully utilized. It is easy to use and has a low production cost. It can not only meet the temperature rise tolerance requirements when the rated current is large, but also can quickly act and disconnect when a short circuit occurs. BRIEF DESCRIPTION OF THE DRAWINGS
[0022] Figure 1 A schematic diagram of the three-dimensional structure of a DC current limiting fuse with a cooling system proposed by the utility model;
[0023] Figure 2 A schematic diagram of a three-dimensional explosion structure of a DC current limiting fuse with a cooling system proposed by the utility model;
[0024] Figure 3 This is a cross-sectional structural schematic diagram of a DC current limiting fuse with a cooling system proposed by the utility model;
[0025] Figure 4 The utility model provides a schematic diagram of the three-dimensional structure of the fuse of a DC current limiting fuse with a cooling system.
[0026] In the figure: 1. fan; 2. mounting plate; 3. first connecting row; 4. first copper pole; 5. sealing ring; 6. sealing gasket; 7. melt; 701. narrow band portion; 702. square hole; 8. inner insulating tube; 9. outer insulating tube; 10. second copper pole; 11. second connecting row. DETAILED DESCRIPTION
[0027] The technical solution of this patent is further described in detail below in conjunction with specific implementation methods.
[0028] The embodiments of the present invention are described in detail below, and examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.
[0029] In the description of this patent, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside", etc., indicating the orientation or position relationship, are based on the orientation or position relationship shown in the drawings, and are only for the convenience of describing this patent and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on this patent.
[0030] In the description of this patent, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", "connected", and "set" should be understood in a broad sense, for example, it can be fixedly connected or set, or it can be detachably connected or set, or connected or set in one piece. For ordinary technicians in this field, the specific meanings of the above terms in this patent can be understood according to specific circumstances.
[0031] Reference Figure 1-4 , a DC current limiting fuse with a cooling system, is used for current overload protection. In order to enable the fuse to respond in time to disconnect the circuit, it can also reduce the temperature rise of the fuse.
[0032] The DC current limiting fuse with a cooling system comprises an inner insulating tube 8, an outer insulating tube 9, a plurality of fuses 7 and a fan 1;
[0033] The inner insulating tube 8 is tubular and made of insulating material. The inner diameter of the inner insulating tube 8 can be designed according to the required heat dissipation conditions. The first copper pole 4 and the second copper pole 10 are fixedly connected at both ends of the inner insulating tube 8. The first copper pole 4 and the second copper pole 10 are provided with a fixing groove on one side close to the inner insulating tube 8. A sealing gasket 6 is provided inside the fixing groove. The sealing gasket 6 is made of rubber. The diameter of the fixing groove corresponds to the outer diameter of the inner insulating tube 8, so that the two ends of the inner insulating tube 8 can be inserted into the fixing grooves of the first copper pole 4 and the second copper pole 10 respectively. The sealing gasket 6 is squeezed to ensure the seal between the copper pole and the inner insulating tube 8. The sealing gasket 5 is an annular sheet structure, one side of which is in contact with the end face of the inner insulating tube 8. The other side is in contact with the bottom surface of the copper pole fixing groove. The thickness needs to be designed to meet the extrusion required for sealing, and the width is consistent with the thickness of the inner insulating tube 8. The two end surfaces of the inner insulating tube 8 are both provided with first threaded holes at equal intervals in an annular manner. The first copper pole 4 and one side of the second copper pole 10 are both provided with first through holes at equal intervals in an annular manner. The first through holes are countersunk holes, and each first through hole is matched with a first threaded hole so that the first copper pole 4 and the second copper pole 10 can be fixed to the two end surfaces of the inner insulating tube 8 by screws respectively. A through hole is provided in the middle of the first copper pole 4 and the second copper pole 10, and the through hole coincides with the center line of the inner insulating tube 8, so that external air can flow through the interior of the inner insulating tube 8.
[0034] Each melt 7 is made of silver sheet, and each melt 7 is provided with a plurality of narrow band portions 701 at equal intervals along the length direction, and a plurality of square holes 702 are provided at equal intervals along the width direction of the melt 7 at the narrow band portion 701, and the square hole is a rectangle with a width of 2 mm and an adjustable length. The width of the narrow band portion 701 is the remaining narrow path after the square hole is cut off from the melt 7, and the width and number of the narrow band portions 701 are adjusted with the rated current and the short-circuit current characteristics to improve the current density during flow or short circuit and ensure the consistency of the fusing of the narrow band portion 701. By adjusting the total width and length of the melt 7, the rated current and the breaking voltage level can be adjusted. The two ends of each melt 7 are L-shaped, and the two ends are fixedly connected to the first copper pole 4 and the second copper pole 10 respectively by spot welding, and a plurality of melts 7 are evenly distributed in a ring shape and welded between the first copper pole 4 and the second copper pole 10 at equal intervals, and a firm connection needs to be ensured.
[0035] The outer insulating tube 9 is tubular and made of insulating material. It is sleeved on the outside of the first copper pole 4 and the second copper pole 10. The outside of the first copper pole 4 and the second copper pole 10 are both provided with an annular groove. The inside of the annular groove is provided with a sealing ring 5 made of rubber. The sealing ring 5 is located between the copper pole and the outer insulating tube 9 to seal the copper pole and the outer insulating tube 9. The outer annular surfaces of the first copper pole 4 and the second copper pole 10 are provided with second threaded holes at equal intervals. The outer walls of the two ends of the outer insulating tube 9 are provided with second through holes at equal intervals. The second through holes are countersunk holes. Each second through hole is adapted to a second threaded hole so that the first A copper pole 4 and a second copper pole 10 are fixed to the two ends of the outer insulating tube 9 by screws respectively. The sealing ring 5 is stuck in the annular groove of the outer wall of the copper pole. By designing the groove size and the diameter and ring diameter parameters of the sealing ring 5, it cooperates with the outer insulating tube 9 to form extrusion to ensure the sealing between the outer side of the copper pole and the outer insulating tube 9. Each melt 7 is located between the inner insulating tube 8 and the outer insulating tube 9. There is a certain designed distance between the melt 7 and the outer wall of the inner insulating tube 8 and the inner wall of the outer insulating tube 9, and the sealed space between the inner insulating tube 8 and the outer insulating tube 9 is evenly and densely filled with quartz sand, which can fully absorb the arc energy when the melt 7 starts arcing.
[0036] One side of the first copper pole 4 is fixedly connected to the first connecting row 3 by bolts, and one side of the second copper pole 10 is fixedly connected to the second connecting row 11 by bolts. Ventilation holes are provided on one side of the first connecting row 3 and the second connecting row 11, and the ventilation holes coincide with the center line of the inner insulating tube 8. A mounting plate 2 is provided on one side of the first connecting row 3, and a countersunk hole is provided on one side of the mounting plate 2 so that the first connecting row 3 and the mounting plate 2 are fixed by bolts. A third threaded hole is provided on the side of the mounting plate 2 away from the first connecting row 3. The fan 1 is fixedly connected to the third threaded hole of the mounting plate 2 by bolts. The spacing between the countersunk hole and the third threaded hole on the mounting plate 2 needs to ensure insulation requirements. The countersunk hole fixedly installed with the first connecting row 3 can be coated with insulating material to increase insulation performance after the fixing bolts are installed. The mounting plate 2 A reserved space is provided on one side for mounting bolts of the first connecting row 3 and the first copper pole 4, which is cylindrical but not penetrating to ensure insulation between the high-voltage side and the fan 1. The mounting plate 2 is made of insulating material, and it is necessary to ensure isolation between strong and weak electricity after the fan 1 is installed. A circular hole is provided in the middle of the mounting plate 2, and the diameter of the circular hole is consistent with the inner diameter of the inner insulating tube 8, and the center lines of the fan 1, the circular hole and the inner insulating tube 8 coincide. The size and air volume of the fan are designed with reference to the actual working conditions. An insulating annular ring is provided on the side of the mounting plate 2 close to the first connecting row 3, and the annular ring can be inserted into the ventilation hole of the first connecting row 3 and the through hole of the first copper pole 4. The inner wall of the annular ring is connected to the inner wall of the circular hole, and when the annular ring is installed, one side of it will be inserted into the through hole of the first copper pole 4 and contact with the sealing gasket 6 with a certain extrusion to ensure sealing.
[0037] The working principle of the DC current limiting fuse with cooling system is as follows: the fuse is connected to the circuit through the first connecting row 3 and the second connecting plate 11, and the current of the circuit flows through the first connecting row 3, the first copper pole 4, the melt 7, the second copper pole 10 and the second connecting plate 11 in sequence. The heat generated by the melt 7 at the rated current is transferred to the inner insulating tube 8 and the outer insulating tube 9 through the quartz sand filled between the inner insulating tube 8 and the outer insulating tube 9. The heat of the inner insulating tube 8 is operated by the fan 1, so that the external air passes through the ventilation holes of the first connecting row 3 and the through holes of the first copper pole 4 in sequence, enters the interior of the inner insulating tube 8, and cools the inner cavity of the inner insulating tube 8. Finally, the hot air is discharged through the through holes of the second copper pole 10 and the ventilation holes of the second connecting plate 11 on the other side in sequence.
[0038] When the short-circuit current of the fuse meets the designed triggering condition of the fuse 7, the fuse 7 will immediately start arcing and perform the breaking and current limiting action.
[0039] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes within the technical scope disclosed by the present invention according to the technical scheme and the utility model concept of the present invention, which should be covered by the protection scope of the present invention.
Claims
1. A DC current limiting fuse with a cooling system, characterized in that: include: Inner insulating tube (8); An outer insulating tube (9) is arranged around the outer periphery of the inner insulating tube (8); A plurality of melts (7), each of the melts (7) being arranged between the inner insulating tube (8) and the outer insulating tube (9), and being arranged at intervals around the inner insulating tube (8); and a fan (1), which is arranged at one end of the inner insulating tube (8) to blow air toward the inside of the inner insulating tube (8).
2. A DC current limiting fuse with a cooling system according to claim 1, characterized in that: The invention also comprises a first copper electrode (4) and a second copper electrode (10), wherein the first copper electrode (4) is arranged at one end of the inner insulating tube (8) and the outer insulating tube (9), and the second copper electrode (10) is arranged at the other end of the inner insulating tube (8) and the outer insulating tube (9), so that a closed space is formed between the inner insulating tube (8) and the outer insulating tube (9), and the closed space is filled with quartz sand. A through hole is provided in the middle of the first copper electrode (4) and the second copper electrode (10), and the through hole coincides with the center line of the inner insulating tube (8). The two ends of each melt (7) are fixedly connected to the first copper electrode (4) and the second copper electrode (10) respectively.
3. A DC current limiting fuse with a cooling system according to claim 2, characterized in that: The first copper pole (4) and the second copper pole (10) are each provided with a fixing groove on one side close to the inner insulating tube (8), and the two end surfaces of the inner insulating tube (8) can be respectively inserted into the fixing grooves of the first copper pole (4) and the second copper pole (10), and a sealing gasket (6) is provided inside the fixing groove to seal between the copper pole and the inner insulating tube (8).
4. A DC current limiting fuse with a cooling system according to claim 3, characterized in that: A first through hole is provided on one side of the first copper pole (4) and the second copper pole (10), and the first through hole is a countersunk hole. Both end surfaces of the inner insulating tube (8) are provided with a first threaded hole, and the first through hole is adapted to the first threaded hole so that the first copper pole (4) and the second copper pole (10) are respectively fixed to the two end surfaces of the inner insulating tube (8).
5. A DC current limiting fuse with a cooling system according to claim 2, characterized in that: The first copper pole (4) and the second copper pole (10) are both provided with an annular groove on their exteriors, and a sealing ring (5) is provided inside the annular groove. The sealing ring (5) is located between the copper pole and the outer insulating tube (9) so as to seal the copper pole and the outer insulating tube (9).
6. A DC current limiting fuse with a cooling system according to claim 5, characterized in that: The first copper pole (4) and the second copper pole (10) are both provided with a second threaded hole on their exteriors, and the outer walls of both ends of the outer insulating tube (9) are provided with second through holes, the second through holes being countersunk holes, and the second through holes are adapted to the second threaded holes so that the first copper pole (4) and the second copper pole (10) are respectively fixed to the two ends of the outer insulating tube (9).
7. A DC current limiting fuse with a cooling system according to claim 2, characterized in that: The invention also comprises a first connection row (3) and a second connection row (11), wherein the first connection row (3) and the second connection row (11) are respectively arranged on one side of the first copper pole (4) and the second copper pole (10), the first connection row (3) and the first copper pole (4) are fixedly connected by bolts, and the second connection row (11) and the second copper pole (10) are fixedly connected by bolts, and the first connection row (3) and the second connection row (11) are both provided with ventilation holes on one side, and the ventilation holes coincide with the center line of the inner insulating tube (8).
8. A DC current limiting fuse with a cooling system according to claim 7, characterized in that: A mounting plate (2) is provided on one side of the first connection row (3), a countersunk hole is provided on one side of the mounting plate (2) so that the first connection row (3) and the mounting plate (2) are fixed by bolts, a third threaded hole is provided on the side of the mounting plate (2) away from the first connection row (3), the fan (1) is fixedly connected to the third threaded hole of the mounting plate (2) by bolts, the mounting plate (2) is made of insulating material, a circular hole is provided in the middle of the mounting plate (2), the diameter of the circular hole is consistent with the inner diameter of the inner insulating tube (8), and the center lines of the fan (1), the circular hole and the inner insulating tube (8) coincide.
9. A DC current limiting fuse with a cooling system according to claim 8, characterized in that: An annular ring is provided on one side of the mounting plate (2) close to the first connection row (3), and the annular ring can be inserted into the ventilation hole of the first connection row (3) and the through hole of the first copper pole (4), and the inner wall of the annular ring is connected to the inner wall of the circular hole.
10. A DC current limiting fuse with a cooling system according to claim 2, characterized in that: Each of the melts (7) is provided with a plurality of narrow band portions (701) at equal intervals along the length direction, and a plurality of square holes (702) are provided at equal intervals along the width direction of the melt (7) at the narrow band portions (701). Both ends of each of the melts (7) are L-shaped, and the two ends are respectively welded to the first copper pole (4) and the second copper pole (10).