A DC controlled fuse

Abstract

The present invention relates to the technical field of fuses, and in particular to a DC controlled fuse. By arranging an insulating fixing seat between a heating plate and a first temperature sensing body, the heating zone and the temperature sensing zone are separated, so that the subsequent flux does not need to be fully filled, effectively reducing the expansion amount of the flux during the gasification process caused by the arc and the carbonization amount during the arc ablation process, thereby improving the breaking capacity and insulation withstand voltage capacity and preventing the shell from being damaged. In addition, while achieving the separation, it is not necessary to set the temperature sensing zone and the heating zone in two shells, thereby reducing the heat transfer path.

Description

Technical Field

[0001] The present invention relates to the technical field of fuses, and in particular to a DC controlled fuse. Background Art

[0002] An existing controlled fuse, as described in CN213124358U, comprises a closed flat shell, wherein the inner cavity of the flat shell is provided with a main circuit and a control circuit, wherein the main circuit comprises a low-melting-point alloy wire, a first electrode sheet and a second electrode sheet, wherein the first electrode sheet and the second electrode sheet are both plate-like structures in a Z-shape, wherein the low-melting-point alloy wire is located between the first electrode sheet and the second electrode sheet and the low-melting-point alloy wire is respectively connected to the first electrode sheet and the second electrode sheet, wherein one end of the first electrode sheet away from the low-melting-point alloy wire and one end of the second electrode sheet away from the low-melting-point alloy wire both extend to the outside of the flat shell; wherein the control circuit comprises a resistive heating element, wherein the resistive heating element is in thermal contact with the first electrode sheet and the second electrode sheet respectively, thereby being able to reliably control the cutoff.

[0003] However, in the above-mentioned controlled fuse, the heating zone and the temperature-sensitive zone are arranged together, and the flux needs to be completely filled, which may easily lead to excessive expansion of the flux during the gasification process and cause explosion. Summary of the invention

[0004] The technical problem to be solved by the present invention is to provide a DC controlled fuse, which effectively reduces the expansion amount of the arc-induced flux during the gasification process and the carbonization amount during the arc ablation process, thereby improving the breaking capacity and insulation withstand voltage capacity and preventing the shell from being damaged.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A DC controlled fuse comprises two mutually arranged electrode sheets, a first temperature sensor and a heating sheet, wherein the heating sheet is arranged between the two electrode sheets and is electrically isolated from the two electrode sheets, the first temperature sensor is arranged at the same end of the two electrode sheets and the two electrode sheets are electrically connected through the first temperature sensor, and further comprises an insulating fixing seat, wherein the insulating fixing seat is arranged between the heating sheet and the first temperature sensor and the opposite ends of the insulating fixing seat are respectively connected to the two electrode sheets.

[0007] The beneficial effects of the present invention are:

[0008] The present invention provides a DC controlled fuse, wherein the electrode sheet and the first temperature sensing body constitute the main circuit, and the electrode sheet and the heating sheet constitute the control circuit. By setting an insulating fixing seat between the heating sheet and the first temperature sensing body, the heating area and the temperature sensing area are separated, so that the subsequent flux does not need to be fully filled, effectively reducing the expansion amount of the flux during the gasification process caused by the arc and the carbonization amount during the arc ablation process, improving the breaking capacity and insulation withstand voltage capacity, and preventing the shell from being damaged. In addition, while achieving the separation, it is not necessary to set the temperature sensing area and the heating area in two shells, reducing the heat transfer path. BRIEF DESCRIPTION OF THE DRAWINGS

[0009] Figure 1 This is a structural schematic diagram of a DC controlled fuse according to Embodiment 1 of the present invention;

[0010] Figure 2 This is a schematic structural diagram of an insulating fixing seat of a DC controlled fuse according to the first embodiment of the present invention;

[0011] Figure 3 An exploded view of a DC controlled fuse according to Embodiment 1 of the present invention;

[0012] Figure 4 A cross-sectional view of a DC controlled fuse according to Embodiment 1 of the present invention;

[0013] Figure 5 This is a structural schematic diagram of a DC controlled fuse according to the second embodiment of the present invention;

[0014] Figure 6 A first electrical connection diagram of a heating plate of a DC controlled fuse according to the first embodiment of the present invention;

[0015] Figure 7 A second electrical connection diagram of a heating plate of a DC controlled fuse according to the first embodiment of the present invention;

[0016] Figure 8 This is a structural schematic diagram of a DC controlled fuse having a housing with a cutout according to a third embodiment of the present invention;

[0017] Fig. 9 This is a schematic structural diagram of a DC controlled fuse having a chamfered housing according to a third embodiment of the present invention;

[0018] Description of labels:

[0019] 101. Shell;

[0020] 102. Cover plate;

[0021] 103, left electrode;

[0022] 104. The first temperature sensor;

[0023] 105, right electrode;

[0024] 106. Flux;

[0025] 107. Insulation fixing seat;

[0026] 107a, through groove;

[0027] 107b, partition;

[0028] 107c, through hole;

[0029] 107d, heating plate positioning groove;

[0030] 108, TCO2 left pin;

[0031] 109. Second temperature sensor;

[0032] 110, TCO2 right pin;

[0033] 111. TCO2 flux;

[0034] 112, TCO2 left positioning sleeve;

[0035] 113, TCO2 right positioning sleeve;

[0036] 114. Heating tablets;

[0037] 114a, right pin of heating element;

[0038] 114b, left pin of heating element;

[0039] 115. Positioning piece;

[0040] 116. Positioning ring;

[0041] 117, upper pin;

[0042] 118, lower pin;

[0043] 119. Incision;

[0044] 120. Chamfer. DETAILED DESCRIPTION

[0045] In order to explain the technical content, achieved objectives and effects of the present invention in detail, the following is an explanation in conjunction with the implementation modes and the accompanying drawings.

[0046] Please refer to Figure 1-Figure 4A DC controlled fuse provided by the present invention includes two mutually arranged electrode sheets, a first temperature sensor and a heating sheet, wherein the heating sheet is arranged between the two electrode sheets and is electrically isolated from the two electrode sheets, the first temperature sensor is arranged at the same end of the two electrode sheets and the two electrode sheets are electrically connected through the first temperature sensor, and also includes an insulating fixing seat, wherein the insulating fixing seat is arranged between the heating sheet and the first temperature sensor and the opposite ends of the insulating fixing seat are respectively connected to the two electrode sheets.

[0047] From the above description, it can be seen that the beneficial effects of the present invention are:

[0048] The present invention provides a DC controlled fuse, wherein the electrode sheet and the first temperature sensing body constitute the main circuit, and the electrode sheet and the heating sheet constitute the control circuit. By setting an insulating fixing seat between the heating sheet and the first temperature sensing body, the heating area and the temperature sensing area are separated, so that the subsequent flux does not need to be fully filled, effectively reducing the expansion amount of the flux during the gasification process caused by the arc and the carbonization amount during the arc ablation process, improving the breaking capacity and insulation withstand voltage capacity, and preventing the shell from being damaged. In addition, while achieving the separation, it is not necessary to set the temperature sensing area and the heating area in two shells, reducing the heat transfer path.

[0049] Furthermore, the electrode sheet is provided with a plurality of contact fingers arranged in a line, and the contact fingers arranged opposite to each other on the two electrode sheets form a group and are electrically connected through a first temperature sensor.

[0050] Furthermore, the insulating fixing seat is provided with a through slot corresponding to the contact finger position, and the insulating fixing seat is provided with a partition for isolating a plurality of first temperature sensing bodies, close to one side of the first temperature sensing body and located between two adjacent through slots.

[0051] From the above description, it can be seen that by designing the partition, alloy convergence is avoided and the creepage distance and electrical clearance are guaranteed.

[0052] Furthermore, the first temperature sensing body is in the shape of a flat long strip, and the end of the contact finger is provided with a receiving groove with an opening, and the groove width of the receiving groove is adapted to the width of the first temperature sensing body.

[0053] From the above description, it can be seen that the first temperature sensing body is in the shape of a flat strip. Due to the skin effect of current, the current mainly flows on the surface of the conductive medium. The flat alloy design increases the current carrying capacity while also making it easier to absorb and dissipate heat.

[0054] Furthermore, the first temperature sensing body is U-shaped, and the width of the first temperature sensing body corresponding to the U-shaped opening is adapted to the distance between the outer surfaces of the two contact fingers arranged opposite to each other.

[0055] It can be seen from the above description that the above design facilitates assembly.

[0056] Furthermore, it also includes a second temperature sensor, which is inserted into the insulating fixing seat and connected to the heating plate.

[0057] From the above description, it can be seen that by setting the second temperature sensor, the controlled fuse has a self-protection function. The insulating fixing seat is provided with a through hole for accommodating the second temperature sensor to pass through, so that the second temperature sensor is placed in the insulating fixing seat, the relative position is fixed, and the heat transfer path is stable.

[0058] Furthermore, two end portions of the second temperature sensing body are sleeved with positioning sleeves, and the positioning sleeves are fixedly connected to the heating plate.

[0059] It can be seen from the above description that the position between the second temperature sensing body and the heating sheet can be kept relatively fixed to meet the electrical performance.

[0060] Furthermore, two opposite side surfaces of the heating sheet are in contact with two electrode sheets respectively.

[0061] From the above description, it can be seen that the left and right electrodes are in sheet shape and partially overlapped. The heating sheet is arranged between the left electrode and the right electrode, and is arranged closely to the two electrodes, which increases the heat absorption surface of the electrode and the heating sheet, shortens the heat transfer path, makes the heat transfer more efficient, and has the effect of average heat.

[0062] Furthermore, the electrode sheet has a bending portion, and the two bending portions are arranged opposite to each other to form a sandwich layer. The heating sheet is arranged in the sandwich layer, and the area of ​​the heating sheet is matched with the area of ​​the bending portion.

[0063] It can be seen from the above description that the design of the interlayer allows the heating sheet and the electrode sheet to fit more fully and effectively, thereby improving the efficiency of heat conduction and achieving rapid disconnection. In the existing structure where no interlayer is designed and only one side or part of the area of ​​the heating sheet is in contact with the electrode sheet, at least two heating sheets are usually required to achieve rapid disconnection. However, with the interlayer structure of the present application, only one heating sheet is needed to achieve the same or better effect. And by bending, while achieving the interlayer, the external parts of the left and right electrodes are in the same plane, which is convenient for installation.

[0064] Furthermore, a heat-conducting material is provided at the junction of the heating sheet and the electrode sheet.

[0065] It can be seen from the above description that the heat conduction rate can be improved through the above structure.

[0066] Furthermore, it also includes a positioning ring and a positioning member; a mounting hole is respectively provided on the two electrode sheets and the heating sheet, and the three mounting holes are coaxially arranged, the positioning ring is embedded in the mounting hole, and the positioning member is passed through the positioning ring to form the two electrode sheets and the heating sheet as a whole.

[0067] It can be seen from the above description that, through the above structure, the positioning member and the positioning ring are cooperated and tightened, so that the heating plate is closely fitted with the left and right electrodes.

[0068] Furthermore, the diameters of the mounting holes on the two electrode sheets are equal, and the diameter of the mounting hole on the heating sheet is smaller than the diameter of the mounting hole on the electrode sheet.

[0069] From the above description, it can be seen that the mounting holes on the two electrode sheets have the same diameter, and the mounting hole diameter of the heating sheet is smaller, to prevent the alloy from flowing over, which will shorten the creepage distance and cause electrical breakdown.

[0070] Furthermore, a heating plate positioning groove is provided at a middle position of a side surface of the insulating fixing seat close to the heating plate, and the heating plate positioning groove is adapted to the heating plate.

[0071] It can be seen from the above description that providing a heating plate positioning groove can limit the position of the heating plate between the two electrode plates, thereby ensuring a better heat conduction effect.

[0072] Furthermore, it also includes a shell with an opening at one end and a cover plate adapted to the opening, the electrode sheet, the first temperature sensor, the heating sheet and the insulating fixing seat are all arranged in the shell, and the space between the first temperature sensor and the inner wall of the shell is filled with a flux coated on the surface of the first temperature sensor.

[0073] Furthermore, two opposite side walls of the shell are provided with U-shaped grooves for the electrode sheet to partially pass through.

[0074] It can be seen from the above description that the above structure facilitates the assembly of the electrode sheet.

[0075] Furthermore, the two electrode sheets are respectively provided with pins at one end away from the first temperature sensing body, and the cover plate is provided with through holes for the two pins to pass through.

[0076] Furthermore, a glue hole is provided on the portion of the electrode sheet located in the shell, and when the shell is filled with sealing glue, the sealing glue passes through the glue hole.

[0077] It can be seen from the above description that the bonding force between the sealing glue and the electrode can be improved and the heat conduction can be reduced, so that the heat is transferred toward the first temperature sensing body.

[0078] Furthermore, the side wall of the shell is provided with an opening, a cutout or a chamfer corresponding to the position of the first temperature sensor.

[0079] From the above description, it can be known that by providing holes, cuts or chamfers in the side wall, the shell wall thickness is reduced, or part of the shell wall is reduced, so that when the alloy separates the organic material and gasifies to generate pressure, directional pressure relief is performed.

[0080] Please refer to Figure 1-Figure 4 ,as well as Figure 6and Figure 7 , Embodiment 1 of the present invention is:

[0081] A DC controlled fuse provided by the present invention comprises two mutually arranged electrode sheets, a first temperature sensing body 104 and a heating sheet 114;

[0082] The electrode sheet has a bending portion, and the bending portions of the two electrode sheets are arranged relative to each other to form a sandwich with a spacing therebetween. The two electrode sheets are arranged symmetrically with respect to each other. The two electrode sheets are respectively a left electrode 103 and a right electrode 105. The heating sheet 114 is arranged in the sandwich and the two opposite sides of the heating sheet are respectively in close contact with the two electrode sheets. The heating sheet 114 has a heating sheet right pin 114a and a heating sheet left pin 114b. Figure 6 and Figure 7 As shown, it is an electrical connection diagram of the right pin 114a and the left pin 114b of the heating plate. In this scheme, two connection methods are provided, one is that one of the right pin 114a and the left pin 114b of the heating plate is not connected, and serves as a port; the other is that both the right pin 114a and the left pin 114b of the heating plate are connected, and there is no port. The area of ​​the heating plate is adapted to the area of ​​the bending portion. Specifically: the heating plate is arranged between the two electrode plates and is electrically isolated from the two electrode plates. And the junction of the heating plate and the electrode plate is provided with a heat-conducting material, such as thermal conductive silicone grease, which can increase the heat conduction rate.

[0083] In order to make the two electrode sheets fit closely with the heating sheet, a positioning ring 116 and a positioning member 115 are further included; a mounting hole is respectively provided on the two electrode sheets and the heating sheet, and the three mounting holes are coaxially arranged, the positioning ring is embedded in the mounting hole, and the positioning member is passed through the positioning ring to make the two electrode sheets and the heating sheet form a whole. In this embodiment, the positioning ring and the positioning member are both made of insulating materials. The mounting holes on the two electrode sheets have the same diameter, and the mounting hole of the heating sheet has a smaller diameter to prevent the creepage distance from being shortened when the alloy flows over, thereby preventing electrical breakdown.

[0084] The electrode sheet is provided with a plurality of contact fingers arranged in a line, and there is a spacing between two adjacent contact fingers. In order to adapt to first temperature sensors of different structures, the design of the end of the contact fingers will also be different. In this embodiment, the first temperature sensor is in the shape of a flat long strip. Therefore, the end of the contact finger is provided with a receiving groove with an opening, and the groove width of the receiving groove is adapted to the width of the first temperature sensor, so that the first temperature sensor can be arranged at the same end of the two electrode sheets and the two electrode sheets can be electrically connected through the first temperature sensor.

[0085] The DC controlled fuse further comprises an insulating fixing seat, which is arranged between the heating plate and the first temperature sensing body and the opposite ends of which are respectively connected to two electrode plates. Specifically:

[0086] The insulating fixing seat 107 is provided with through grooves 107a at the positions corresponding to the contact fingers, that is, the number of through grooves is equal to the number of contact fingers, and the inner diameter of the through grooves is also adapted to the outer diameter of the contact fingers, and the two are interference fit. The insulating fixing seat is close to one side of the first temperature sensing body and is provided with a partition 107b for isolating multiple first temperature sensing bodies between two adjacent through grooves. The insulating fixing seat is provided with a heating plate positioning groove 107d in the middle position close to one side of the heating plate, and the heating plate positioning groove is adapted to the heating plate. During assembly, the contact finger of the electrode sheet passes through the through groove from the insulating fixing seat close to one side of the heating plate to the insulating fixing seat close to one side of the first temperature sensing body, and the contact finger has a protruding portion for cooperating with the first temperature sensing body. In this embodiment, the number of contact fingers is 5. The number of the partitions is 4.

[0087] A through hole for the second temperature sensor 109 to pass through is provided in the middle position of the insulating fixing seat, so that the second temperature sensor can pass through the insulating fixing seat and be connected to the heating plate. By providing the second temperature sensor, the controlled fuse has a self-protection function. The insulating fixing seat is provided with a through hole 107c for accommodating the second temperature sensor to pass through, so that the second temperature sensor is placed in the insulating fixing seat, the relative position is fixed, and the heat transfer path is stable. Preferably, the two ends of the second temperature sensor are provided with positioning sleeves, and the two positioning sleeves are TCO2 left positioning sleeve 112 and TCO2 right positioning sleeve 113 respectively; the two ends of the second temperature sensor are provided with TCO2 left pin 108 and TCO2 right pin 109; the positioning sleeve is connected to the heating plate. The positioning sleeve is made of insulating material.

[0088] The DC controlled fuse also includes a housing 101 with an opening at one end and a cover plate 102 adapted to the opening. The electrode sheet, the first temperature sensor, the heating sheet and the insulating fixing seat are all arranged in the housing. The first temperature sensor and the inner wall of the housing are filled with a flux 106 coated on the surface of the first temperature sensor. In this solution, the flux does not need to be filled. The opposite side walls of the housing are provided with a U-shaped groove for the electrode sheet to pass through. The portion of the electrode sheet located outside the housing enters from the notch of the U-shaped groove to complete the assembly of the electrode sheet.

[0089] The two electrode sheets are provided with pins at one end away from the first temperature sensing body, and the cover plate is provided with through holes for the two pins to pass through. The two pins are respectively an upper pin 117 and a lower pin 118 of the product.

[0090] The portion of the electrode sheet located in the shell is provided with an adhesive hole. When the shell is filled with sealing glue, the sealing glue passes through the adhesive hole, which can improve the bonding force between the sealing glue and the electrode and reduce heat conduction, so that the heat is transferred toward the first temperature sensing body.

[0091] Please refer to Figure 2-Figure 5, Embodiment 2 of the present invention is:

[0092] On the basis of the above-mentioned embodiment 1, the first temperature sensor 104 is further improved in structure, that is, the first temperature sensor is U-shaped, which can also be called n-shaped, and the width of the first temperature sensor corresponding to the U-shaped opening is adapted to the distance between the outer surfaces of the two oppositely arranged contact fingers. During assembly, the inner surfaces of the two side walls of the first temperature sensor corresponding to the U-shaped opening are respectively overlapped on the outer surfaces of the two contact fingers.

[0093] like Figure 8-Figure 9 , Embodiment 3 of the present invention is: the side wall of the housing is provided with an opening, a cutout 119 or a chamfer 120 corresponding to the position of the first temperature sensing body. By providing a hole, a cutout or a chamfer on the side wall, the thickness of the housing wall is reduced, or part of the housing wall is reduced, so that when the alloy separates the organic material and gasifies to generate pressure, directional pressure relief is performed.

[0094] The above descriptions are merely embodiments of the present invention and are not intended to limit the patent scope of the present invention. Any equivalent transformations made using the contents of the present invention's specification and drawings, or directly or indirectly applied in related technical fields, are also included in the patent protection scope of the present invention.

Claims

1. A DC controlled fuse, comprising two mutually arranged electrode sheets, a first temperature sensing body and a heating sheet, wherein the heating sheet is arranged between the two electrode sheets and is electrically isolated from the two electrode sheets, the first temperature sensing body is arranged at the same end of the two electrode sheets and the two electrode sheets are electrically connected through the first temperature sensing body, characterized in that: It also includes an insulating fixing seat, which is arranged between the heating sheet and the first temperature sensing body, and the opposite ends of the insulating fixing seat are respectively connected to the contact fingers at the two ends of the two electrode sheets, so that the insulating fixing seat separates the heating area where the heating sheet is located from the temperature sensing area where the first temperature sensing body is located; it also includes a shell with an opening at one end, the electrode sheet, the first temperature sensing body, the heating sheet and the insulating fixing seat are all arranged in the shell, and the first temperature sensing body and the inner wall of the shell are filled with a flux coated on the surface of the first temperature sensing body; The top of the insulating fixing seat is provided with a protrusion, and the insulating fixing seat is provided with a through groove for the contact finger to pass through at the corresponding contact finger position, and the contact finger of the electrode sheet and the first temperature sensing body are electrically connected and U-shapedly erected above the protrusion; The two opposite sides of the heating sheet are in contact with two electrode sheets respectively; The electrode sheet has a bending portion, two bending portions are arranged opposite to each other to form an interlayer, the heating sheet is arranged in the interlayer, and the area of ​​the heating sheet is adapted to the area of ​​the bending portion; A heat-conducting material is provided at the junction of the heating sheet and the electrode sheet; It also includes a positioning ring and a positioning member; a mounting hole is respectively provided on the two electrode sheets and the heating sheet, and the three mounting holes are coaxially arranged, the positioning ring is embedded in the mounting hole, and the positioning member is passed through the positioning ring to form the two electrode sheets and the heating sheet into one.

2. A DC controlled fuse according to claim 1, characterized in that: The electrode sheet is provided with a plurality of contact fingers arranged in a line, and the contact fingers arranged opposite to each other on two electrode sheets form a group and are electrically connected through a first temperature sensing body.

3. A DC controlled fuse according to claim 2, characterized in that: The insulating fixing seat is provided with a through slot corresponding to the contact finger position, and the insulating fixing seat is provided with a partition for isolating a plurality of first temperature sensing bodies, close to one side of the first temperature sensing body and located between two adjacent through slots.

4. A DC controlled fuse according to claim 2, characterized in that: The first temperature sensing body is in a flat and long strip shape, and an accommodating groove with an opening is provided at the end of the contact finger, and the groove width of the accommodating groove is adapted to the width of the first temperature sensing body.

5. A DC controlled fuse according to claim 2, characterized in that: The first temperature sensing body is U-shaped, and the width of the first temperature sensing body corresponding to the U-shaped opening is adapted to the distance between the outer surfaces of the two contact fingers arranged opposite to each other.

6. A DC controlled fuse according to claim 2, characterized in that: It also includes a second temperature sensing body, which is inserted into the insulating fixing seat and connected to the heating sheet.

7. A DC controlled fuse according to claim 6, characterized in that: Positioning sleeves are provided at both ends of the second temperature sensing body, and the positioning sleeves are fixedly connected to the heating sheet.

8. A DC controlled fuse according to claim 1, characterized in that: The apertures of the mounting holes on the two electrode sheets are equal, and the aperture of the mounting hole on the heating sheet is smaller than the aperture of the mounting hole on the electrode sheet.

9. A DC controlled fuse according to claim 1, characterized in that: A heating plate positioning groove is provided at a middle position of a side surface of the insulating fixing seat close to the heating plate, and the heating plate positioning groove is adapted to the heating plate.

10. A DC controlled fuse according to claim 1, characterized in that: Also included is a cover plate matched with the opening.

11. A DC controlled fuse according to claim 10, characterized in that: The side wall of the shell is provided with an opening, a cutout or a chamfer corresponding to the position of the first temperature sensing body.

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