Combined mutual inductor and preparation method thereof

Abstract

The invention relates to the technical field of mutual inductors, in particular to a combined mutual inductor and a preparation method thereof. The combined type mutual inductor comprises a shell; the first winding coil and the second winding coil are arranged in a shell in a stacked mode and located on the upper end portion and the lower end portion of a supporting body in the shell respectively. The first U-shaped conductor rod and the second U-shaped conductor rod are arranged in parallel; and the output pins are electrically connected with the ends of the first winding coil and the second winding coil one by one and all extend out of the shell. According to the invention, the two transformers are integrally designed and prepared, so that the occupied space of the product is reduced, and miniaturization development and reduction of the manufacturing cost are facilitated; the two winding coils are arranged in the same shell, so that the problem of poor connection stability of a laminated mutual inductor is solved, and the safety and reliability of the mutual inductor and a circuit are greatly improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of mutual inductors, in particular to a combined mutual inductor and a preparation method thereof. BACKGROUND

[0002] With the popularization of electric vehicles, the safety and reliability of the charging process have attracted the attention of the whole society, and people's concern about the safety and reliability of electricity has also increased, so the country has introduced a new mandatory standard of "Safety Requirements and Test Specifications for Electric Vehicle Power Supply Equipment" to put forward higher requirements for the safety and reliability of electric vehicle power supply and charging equipment.

[0003] As an electronic component with functions such as power metering, leakage current detection, and leakage protection, the current transformer has been widely used in various electrical equipment and facilities. The rapid development of the electric vehicle industry and the improvement of charging safety level also bring new opportunities and challenges to the current transformer. Electric vehicle charging equipment is a highly integrated and high-power electrical facility with high safety requirements. In addition to accurate power metering, it also needs to accurately detect leakage current. The current transformer used for power metering and leakage detection is two types of transformer products. The metering transformer and the leakage protection transformer are basically used separately on the market. If the traditional product scheme is used, assembling multiple transformers on the circuit board will occupy a large area and space on the circuit board, which is not conducive to the development of small and integrated devices. In the prior art, there are schemes for combining metering transformers and leakage protection transformers by stacking the housings and penetrating the pins (such as patents CN223038764U and CN223023047U). However, the reliability of such simple stacking structure is poor, and the upper and lower structures may separate during actual use, directly affecting the safety of the circuit. Moreover, the simple stacking method of the two types of transformers has many manufacturing processes and high manufacturing cost. SUMMARY

[0004] The present application aims to provide a combined mutual inductor to solve the above technical problems. The present application also aims to provide a preparation method of a combined mutual inductor to solve the above technical problems.

[0005] The technical problems solved by the present application can be achieved by the following technical solutions: A combined mutual inductor, comprising, a housing; a first winding coil and a second winding coil, which are stacked in the housing and are respectively located on the upper end and the lower end of a support in the housing; a first U-shaped conductor rod and a second U-shaped conductor rod arranged in parallel, a first single arm of the first U-shaped conductor rod penetrating an inner coil of the first winding coil and extending out of the shell at an end, and a first single arm of the second U-shaped conductor rod penetrating the inner coil of the first winding coil and an inner coil of the second winding coil and extending out of the shell at an end; a set of output pins arranged in parallel, the output pins being electrically connected to the ends of the first winding coil and the second winding coil one by one and all extending out of the shell.

[0006] Preferably, the upper end of the support body comprises, a first middle column, which is an internal hollow structure, the first single arm of the first U-shaped conductor rod being arranged in the first middle column, the height of the first middle column being not less than the height of the first winding coil; a first arc-shaped plate arranged at a certain distance on the side of the first middle column, the curvature of the first arc-shaped plate being matched with the inner coil of the first winding coil, and the inner coil of the first winding coil being connected to the first middle column and the first arc-shaped plate in a clamping manner; a baffle arranged between the outer coil of the first winding coil and the second single arm of the first U-shaped conductor rod.

[0007] Preferably, the lower end of the support body comprises, a second arc-shaped plate arranged on the ring side of the bottom end of the first U-shaped conductor rod, the inner coil of the second winding coil being connected to the second arc-shaped plate in a clamping manner; a limiting block arranged on the outer ring side of the second arc-shaped plate, one end of the second winding coil abutting against the limiting block, and the height of the limiting block being not less than the height of the protrusion at the bottom end of the first U-shaped conductor rod.

[0008] Preferably, the support body further comprises, a through hole penetrating the support body and being between the first winding coil and the second winding coil, the first single arm of the second U-shaped conductor rod sequentially penetrating the inner coil of the second winding coil, the through hole and the inner coil of the first winding coil from bottom to top; a wire collecting groove penetrating the support body and being located at the outer coil of the first winding coil and the second winding coil close to the coil end, for penetrating the coil end of the first winding coil and / or the coil end of the second winding coil; a pin slot arranged on one side close to the wire collecting groove, the number of the pin slot being consistent with the total number of the coil ends of the first winding coil and the second winding coil, and the coil ends of the first winding coil and the second winding coil being inserted into the pin slot after being connected to the pins.

[0009] Preferably, the shell further comprises an upper cover and a lower shell, the upper cover and the lower shell constitute a closed structure, the support body is located in the closed structure, the upper cover is provided with a bayonet at the edge of the lower shell, the upper cover is provided with a lead-out groove at one side of the needle slot, the needle is led out to the outside of the upper cover through the lead-out groove after being inserted into the needle slot, and the upper cover is further provided with a lead-out hole penetrating upward and downward, the top end of the first U-shaped conductor rod and the second U-shaped conductor rod are led out to the outside of the upper cover through the lead-out hole.

[0010] The needle is provided with a needle buckle, and the support body is further provided with a clamping buckle matched with the needle buckle at one side of the needle slot.

[0011] Preferably, the lower shell comprises, a clamping groove provided at the edge of the lower shell close to the upper cover, the clamping groove corresponding to the bayonet; a U-shaped through groove, a first end of the U-shaped through groove being located in the interior of the lower shell, a second end of the U-shaped through groove being located at the edge of the lower shell, the second U-shaped conductor rod being arranged in the U-shaped through groove except for two end portions, and the first end of the U-shaped through groove penetrating the through hole; a ring-shaped groove provided at the edge of the lower shell close to one side of the first U-shaped conductor rod, and the second single arm of the first U-shaped conductor rod being arranged in the ring-shaped groove.

[0012] Preferably, the first winding coil comprises a first ring-shaped magnetic core and at least one group of first coils wound on the first ring-shaped magnetic core; and the second winding coil comprises a second ring-shaped magnetic core and a second coil wound on the second ring-shaped magnetic core.

[0013] Preferably, the shell further comprises an insulating glue filled in the shell and wrapped around the first winding coil, the second winding coil, the first U-shaped conductor rod, the second U-shaped conductor rod, the output needle and the support body.

[0014] A preparation method of a combined mutual inductor, for manufacturing the combined mutual inductor, comprising, Step S1, injection molding: placing the first U-shaped conductor rod and the second U-shaped conductor rod in injection molds of the support body and the lower shell respectively, using an insert injection molding method to obtain a support body with a plastic-coated first U-shaped conductor rod and a lower shell with a plastic-coated second U-shaped conductor rod, and injection molding an upper cover; Step S2, one-time assembly: the first winding coil and the second winding coil obtained are respectively arranged in the upper end portion and the lower end portion of the support body, and the first single arm of the first U-shaped conductor rod penetrates the inner ring of the first winding coil. Step S3, pin welding: the wire ends of the first winding coil and the second winding coil are respectively welded with the pins after passing through the wire slot, and the pins are clamped into the pin slot and the clamping buckle of the support body, to obtain a first assembly; Step S4, secondary assembly: the first assembly obtained in step S3 is loaded into the lower shell (13), and the first single arm of the second U-shaped conductor rod penetrates the inner ring of the first winding coil and the inner ring of the second winding coil, to obtain a second assembly; Step S5, glue pouring: liquid insulation glue is poured into the second assembly obtained in step S4, and the upper cover is installed after the insulation glue is completely solidified.

[0015] Preferably, in step S2, the preparation method of the first winding coil and the second winding coil is that a first annular magnetic core is selected, and a predetermined number of turns and groups of enameled wire are wound on the first annular magnetic core to obtain the first winding coil; a second annular magnetic core is selected, and a predetermined number of turns of enameled wire is wound on the second annular magnetic core to obtain the second winding coil.

[0016] The beneficial effects of the present application are that: due to the above technical scheme, the two transformers are designed and prepared in an integrated manner, which not only reduces the occupied space of the product, but also is more conducive to the miniaturization and integration development of electronic devices, significantly shortens the manufacturing process, simplifies the manufacturing process, and greatly reduces the manufacturing cost; the two winding coils are arranged in the same shell, which solves the problem of poor connection stability of the simple laminated transformer in the prior art, and greatly improves the safety and reliability of the transformer and its circuit. BRIEF DESCRIPTION OF DRAWINGS

[0017] Figure 1 It is a schematic diagram of the overall structure of the combined transformer in the embodiment of the present application; Figure 2 It is an exploded view of the structure of the combined transformer in the embodiment of the present application; Figure 3 It is a schematic diagram of the structure of the upper cover of the combined transformer in the embodiment of the present application; Figure 4 It is a schematic diagram of the structure of the lower shell of the combined transformer in the embodiment of the present application; Figure 5 It is a schematic diagram of the structure of the upper end of the support body of the combined transformer in the embodiment of the present application; Figure 6 It is a schematic diagram of the structure of the lower end of the support body of the combined transformer in the embodiment of the present application; Figure 7 It is a schematic diagram of the combined transformer in the embodiment of the present application after the winding magnetic core is assembled.

[0018] Figure 8This is a schematic diagram illustrating the steps of the preparation method of the combined mutual inductor in an embodiment of the present invention.

[0019] In the attached diagram: 1. Housing; 11. Top cover; 111. Lead-out groove; 112. Bayonet; 113. Lead-out hole; 12. Support body; 121. First central column; 122. First arc-shaped plate; 123. Baffle; 124. Second arc-shaped plate; 125. Limiting block; 126. Through hole; 127. Cable groove; 128. Pin groove; 129. Snap-fit ​​buckle; 13. Lower housing; 131. Snap-fit ​​groove; 132. U-shaped through groove; 133. Annular groove; 2. First winding coil; 3. Second winding coil; 4. First U-shaped conductor rod; 5. Second U-shaped conductor rod; 6. Pin; 61. Pin buckle. Detailed Implementation

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

[0021] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0022] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, but this is not intended to limit the scope of the invention.

[0023] A type of combined current transformer, such as Figures 1 to 7 As shown, including, One shell 1; The first winding coil 2 and the second winding coil 3 are stacked in a housing 1 and are located on the upper and lower ends of a support 12 inside the housing 1, respectively. The first U-shaped conductor rod 4 and the second U-shaped conductor rod 5 are arranged in parallel. The first single arm of the first U-shaped conductor rod 4 passes through the inner circle of the first winding coil 2 and the end extends out of the housing 1. The first single arm of the second U-shaped conductor rod 5 passes through the inner circle of the first winding coil 2 and the inner circle of the second winding coil 3 and the end extends out of the housing 1. A set of parallel output pins 6 are electrically connected to the ends of the first winding coil 2 and the second winding coil 3, and all of them extend out of the housing 1.

[0024] Specifically, the combined current transformer of the present invention includes a housing 1 and a first winding coil 2, a second winding coil 3, a first U-shaped conductor rod 4, a second U-shaped conductor rod 5, and an output pin 6 disposed within the housing 1. The first winding coil 2 and the second winding coil 3 are stacked together via a support 12 and do not contact each other. The first U-shaped conductor rod 4 passes through the first winding coil 2, and the second U-shaped conductor rod 5 passes through the first winding coil 2 and the second winding coil 3 in sequence. All four ends of the first U-shaped conductor rod 4 and the second U-shaped conductor rod 5 extend outside the housing 1. The output pin 6 is electrically connected to each end of the first winding coil 2 and the second winding coil 3, and all extend outside the housing 1. The area inside the housing 1 excluding the first winding coil 2, the second winding coil 3, the first U-shaped conductor rod 4, the second U-shaped conductor rod 5, and the output pin 6 is encapsulated with insulating colloid.

[0025] More specifically, the first winding coil 2 and the second winding coil 3 are stacked one on top of the other. The first U-shaped conductor rod 4 passes through the first winding coil 2 from bottom to top, serving as the primary side port of the first winding coil 2. The second U-shaped conductor rod 5 passes through the second winding coil 3 and the first winding coil 2 from bottom to top, serving as the primary side port of the second winding coil 3.

[0026] The length of the first U-shaped conductor rod 4 is not less than the height of the first winding coil 2, and the length of the second U-shaped conductor rod 5 is not less than the sum of the heights of the first winding coil 2 and the second winding coil 3, so that both the first U-shaped conductor rod 4 and the second U-shaped conductor rod 5 can extend to the outside of the housing 1. In this embodiment, the ends of the first U-shaped conductor rod 4 and the second U-shaped conductor rod 5 are both led out from the upper end of the housing 1.

[0027] The first winding coil 2 and the first U-shaped conductor rod 4 are assembled to form a leakage current transformer, which is mainly used to detect leakage current in actual circuits. The second winding coil 3 and the second U-shaped conductor rod 5 are assembled to form a current transformer, which is used to measure the current flowing through the main circuit.

[0028] This invention integrates two types of current transformers into one unit. Compared with the existing method where two current transformers need to be installed in different areas of the main board, this invention can greatly reduce the space occupied by the product, which is conducive to miniaturization. Moreover, the manufacturing process is simple and the manufacturing cost is greatly reduced. By setting the first winding coil 2 and the second winding coil 3 in the same housing 1, the problem of poor connection stability of the existing stacked current transformers is effectively solved, which greatly improves the safety and reliability of the current transformer and its circuit.

[0029] In a preferred embodiment, such as Figure 5 As shown, the upper end of the support 12 includes, The first central column 121 has an internal hollow structure. The first single arm of the first U-shaped conductor rod 4 is inserted into the first central column 121. The height of the first central column 121 is not less than the height of the first winding coil 2. The first arc plate 122 is set at a certain distance on the side of the first central column 121. The arc of the first arc plate 122 is adapted to the inner ring of the first winding coil 2. The inner ring of the first winding coil 2 can be connected to the ground on the first central column 121 and the first arc plate 122. Baffle 123 is located between the outer ring of the first winding coil 2 and the second single arm of the first U-shaped conductor rod 4.

[0030] Specifically, in this embodiment, the support body 12 can be divided into an upper end and a lower end. The upper end is used to assemble the first winding coil 2, and the lower end is used to assemble the second winding coil 3.

[0031] The upper part includes a first central column 121, a first arc plate 122 and a baffle 123. The interior of the first central column 121 is hollow. One arm of the first U-shaped conductor rod 4 passes through the first central column 121. The height of the first central column 121 is not less than the height of the first winding coil 2. An insulating barrier is formed between the first U-shaped conductor rod 4 and the first winding coil 2 to avoid the situation of withstand voltage breakdown. At least one first arc-shaped plate 122 is provided on the side of the first central column 121. The arc of the plate is approximately the arc of the inner ring of the first winding coil 2. The distance between the first arc-shaped plate 122 and the first central column 121 is also set according to the size of the inner ring of the first winding coil 2. When assembling the first winding coil 2, its inner ring is just snapped onto the first central column 121 and the first arc-shaped plate 122. One or more first arc-shaped plates 122 can be provided according to actual needs, as long as they can match the inner ring of the first winding coil 2. A baffle 123 is also provided between the outer ring of the first winding coil 2 and the other single arm of the first U-shaped conductor rod 4. Its purpose is to isolate the first winding coil 2 and the first U-shaped conductor rod 4 to avoid the breakdown of withstand voltage and affect the normal use of the transformer.

[0032] In a preferred embodiment, such as Figure 6 As shown, the lower end of the support 12 includes, The second arc plate 124 is located on the ring side of the bottom end of the first U-shaped conductor rod 4, and the inner ring of the second winding coil 3 can be grounded and connected to the second arc plate 124. The limiting block 125 is located on the outer ring side of the second arc plate 124. One end of the second winding coil 3 abuts against the limiting block 125. The height of the limiting block 125 is not less than the height of the bottom protrusion of the first U-shaped conductor rod 4.

[0033] Specifically, the lower end includes a second arc plate 124 and a limiting block 125. The second arc plate 124 can be set in one or more as needed. One is set as an annular plate with a larger arc length, while multiple are assembled from multiple annular plates with smaller arc lengths. The arc, spacing, size, etc. are matched according to the size of the inner ring of the second winding coil 3 so that the second winding coil 3 can be snapped onto the second arc plate 124 to prevent the second winding coil 3 from shifting laterally. The outer ring side of the arc plate is also provided with a limiting block 125. The number of limiting blocks 125 is preferably more than three to ensure that the second winding coil 3 can be installed flat. The limiting block 125 is set because the bottom end of the first U-shaped conductor rod 4 also has a certain height. The height of the limiting block 125 is not less than the height of the bottom end protrusion of the first U-shaped conductor rod 4. Of course, the bottom end of the first U-shaped conductor rod 4 can also be set at the upper end. In this case, the limiting block 125 is set on the outer ring side of the first arc plate 122 at the upper end.

[0034] In a preferred embodiment, the support 12 further includes, Through hole 126, passing through support body 12, is located between first winding coil 2 and second winding coil 3. The first single arm of second U-shaped conductor rod 5 passes through the inner circle of second winding coil 3, through hole 126 and inner circle of first winding coil 2 from bottom to top. The wire channel 127 passes through the support body 12 and is located on the outer ring of the first winding coil 2 and the second winding coil 3 near the coil end. It is used to pass through the coil end of the first winding coil 2 and / or the coil end of the second winding coil 3. The pin slot 128 is located on one side near the wire slot 127. The number of pin slots 128 is the same as the total number of coil ends of the first winding coil 2 and the second winding coil 3. After the coil ends of the first winding coil 2 and the coil ends of the second winding coil 3 are connected to the pin 6, they are inserted into the pin slot 128.

[0035] Specifically, the support body 12 also includes a through hole 126, a wire groove 127, and a pin groove 128. The through hole 126 runs through the support body 12 vertically and is located on one side of the first central column 121. When the support body 12 is equipped with the first winding coil 2 and the second winding coil 3, the through hole 126 is located inside the inner ring of the first winding coil 2 and the second winding coil 3. The second U-shaped conductor rod 5 passes through the inner ring of the second winding coil 3, the through hole 126, and the inner ring of the first winding coil 2 from bottom to top, and then leads out from the top cover 11 to the outside. The cable tray 127 extends vertically through the support body 12 and can be located near the coil ends on the outer ring of the first winding coil 2 and the second winding coil 3. The coil end of the first winding coil 2 can enter the lower end through the cable tray 127 from the upper end and be combined with the coil end of the second winding coil 3, so that the coil ends can be uniformly connected to the pins 6 and led out to the outside of the housing 1. The pin slot 128 is located on the side near the cable tray 127. After the coil ends of the first winding coil 2 and the second winding coil 3 are uniformly combined and connected to the pins 6, the pins 6 can be inserted into the pin slots 128 in sequence. The number of pin slots 128 is matched with the number of pins 6.

[0036] In a preferred embodiment, the housing 1 further includes an upper cover 11 and a lower housing 13. The upper cover 11 and the lower housing 13 form a sealed structure. The support body 12 is located inside the sealed structure. The upper cover 11 is provided with a snap-fit ​​112 for connecting the lower housing 13 near the edge of the lower housing 13. The upper cover 11 is provided with a lead-out groove 111 near the pin groove 128. After the pin 6 is inserted into the pin groove 128, it is led out to the outside of the upper cover 11 through the lead-out groove 111. The upper cover 11 is also provided with a lead-out hole 113 that runs vertically through the upper and lower parts. The top ends of the first U-shaped conductor rod 4 and the second U-shaped conductor rod 5 pass through the lead-out hole 113 and lead out to the outside of the upper cover 11.

[0037] The pin 6 is provided with a pin buckle 61, and the support body 12 is also provided with a snap buckle 129 that is adapted to the pin buckle 61 on the side near the pin groove 128.

[0038] The housing 1 of the present invention includes an upper cover 11, a support body 12 and a lower housing 13. The upper cover 11 and the lower housing 13 can be assembled to form a sealed structure. The support body 12 is fitted with a first winding coil 2 and a second winding coil 3 and is housed within the sealed structure.

[0039] Specifically, in this embodiment, the housing 1 includes an upper cover 11, a support body 12, and a lower housing 13. The support body 12 is disposed within the sealed structure formed by the upper cover 11 and the lower housing 13, and is mainly used to support the first winding coil 2 and the second winding coil 3, so that the two do not contact each other and can be placed stably in the sealed structure.

[0040] Specifically, the upper cover 11 is also provided with a lead-out groove 111, a bayonet 112, and a lead-out hole 113. The lead-out groove 111 is located on the edge of the upper cover 11 near the pin groove 128. The number of lead-out grooves 111 is the same as that of the pin groove 128, which is 6. After the pin 6 is inserted into the pin groove 128, it is led out from bottom to top through the lead-out groove 111 to the outside of the upper cover 11. The bayonet 112 is located on the edge of the upper cover 11 and is used to connect the upper cover 11 to the lower housing 13. The lead-out holes 113 are provided on the upper cover 11 through the top and bottom. There are a total of 4 lead-out holes 113, 2 of which are located inside the upper cover 11 and the other 2 are located on the edge of the upper cover 11. One internal lead-out hole 113 and one adjacent edge lead-out hole 113 form a group, which are used to lead out the top ends of the first U-shaped conductor rod 4 and the second U-shaped conductor rod 5, respectively.

[0041] Specifically, the pin 6 has an L-shaped structure, which makes it easy to solder the pin 6 to the coil end and lead it out to the outside of the housing 1. A pin buckle 61 is also provided at the end of the pin 6 near the soldering point. Correspondingly, a snap fastener 129 is also provided at the lower end of the support body 12 near the pin groove 128. The pin buckle 61 can be inserted into the snap fastener 129 to fix the pin 6 to the support body 12.

[0042] Please refer to further details. Figure 2 As shown, the upper cover 11 of the present invention has a snap-fit ​​112 on its edge for connecting with the lower housing 13. A lead-out groove 111 is provided on the side near the pin groove 128. After the pin 6 is inserted into the pin groove 128, it is led out to the outside of the upper cover 11 through the lead-out groove 111 for easy connection with external circuits. The upper cover 11 also has a lead-out hole 113 that runs through the upper and lower parts for leading out the top ends of the first U-shaped conductor rod 4 and the second U-shaped conductor rod 5.

[0043] The upper end of the support body 12 is provided with a hollow first central column 121. The first single arm of the first U-shaped conductor rod 4 passes through the first central column 121 and plays an insulating and barrier role. The first arc plate 122 on the side cooperates with the first central column 121 and snaps into the inner ring of the first winding coil 2.

[0044] A baffle 123 is provided between the outer ring of the first winding coil 2 and the second single arm of the first U-shaped conductor rod 4 to enhance the insulation performance.

[0045] The second arc-shaped plate 124 at the lower end of the support body 12 is used to engage the inner ring of the second winding coil 3, and the limiting block 125 on its outer ring side is used to prevent the second winding coil 3 from shifting.

[0046] The support body 12 has a through hole 126 for the first single arm of the second U-shaped conductor rod 5 to pass through; there is also a wire channel 127 for collecting the coil ends of the first and second winding coils 3; the number of pin slots 128 is the same as the total number of coil ends, and is used to place pins 6.

[0047] In a preferred embodiment, the lower housing 13 includes, The slot 131 is located on the edge of the lower housing 13 near the upper cover 11, and the slot 131 corresponds to the slot 112. U-shaped through groove 132, the first end of U-shaped through groove 132 is located inside the lower housing 13, the second end of U-shaped through groove 132 is located at the edge of the lower housing 13, the second U-shaped conductor rod 5 except for the two ends is inserted in U-shaped through groove 132, and the first end of U-shaped through groove 132 passes through through hole 126. An annular groove 133 is located at the edge of the lower housing 13 near the side of the first U-shaped conductor rod 4, and the second single arm of the first U-shaped conductor rod 4 is located in the annular groove 133.

[0048] Specifically, the lower housing 13 includes a slot 131, a U-shaped through groove 132, and an annular groove 133. The slot 131 is located near the edge of the lower housing 13 close to the upper cover 11. Multiple sets of slots 131 and latches 112 can be provided. In this embodiment, three sets of slots 131 and latches 112 are provided at a certain distance from each other, and their positions correspond to each other. The slots 131 and latches 112 can engage with each other, thereby fixing the upper cover 11 and the lower housing 13 together. The U-shaped through groove 132 is provided inside the lower housing 13, with one end located in the off-center region of the lower housing 13 and the other end located at the edge of the lower housing 13. The U-shaped through groove has a hollow structure. The second U-shaped conductor rod 5 is housed in the U-shaped through groove 132. During assembly, the end of the U-shaped through groove located in the off-center region of the lower housing 13 can pass through the through hole 126 of the support body 12. An annular groove 133 is located at the edge of the lower housing 13, adjacent to one end of the U-shaped through groove. One end of the first U-shaped conductor rod 4 passes through the first central column 121, while the other end is accommodated in the annular groove 133.

[0049] In a preferred embodiment, the first winding coil 2 includes a first toroidal core and at least one set of first coils wound on the first toroidal core; the second winding coil 3 includes a second toroidal core and a second coil wound on the second toroidal core.

[0050] Specifically, the ends of the first coil and the second coil are respectively connected to pins 6, which are engaged in pin slots 128; The first winding coil 2 is the main component of the leakage current transformer, including the first toroidal magnetic core and the first coil wound on the first toroidal magnetic core. The first coil can be selected as one or two sets according to actual needs, and is used as a detection coil to detect the leakage current in the main circuit. There are also cases where three sets of first coils are set. The extra third set of coils is used as a calibration coil, which is usually only wound with a few turns. It is used to calibrate and self-test by simulating leakage current after the transformer is assembled, so as to ensure the good performance of the transformer. The second winding coil 3 is the main component of the current transformer, including the second toroidal core and the second coil wound on the second toroidal core. Usually, only one set of the second coil is provided, which is used to measure the current value flowing through the main circuit.

[0051] More specifically, in this embodiment, there are two sets of first coils and one set of second coils, for a total of 6 coil ends. Each coil end is welded with a pin 6, that is, it contains 6 pins 6. There are also 6 corresponding pin slots 128, and the pins 6 are respectively disposed in the pin slots 128.

[0052] In a preferred embodiment, an insulating colloid is further included, which fills the housing 1 and covers the periphery of the first winding coil 2, the second winding coil 3, the first U-shaped conductor rod 4, the second U-shaped conductor rod 5, the output pin 6, and the support body 12.

[0053] Specifically, the insulating colloid filled inside the housing 1 and covering the winding coil, U-shaped conductor rod, output pin 6 and support body 12 serves as insulation, preventing leakage between internal components. It also fixes the internal components, enhances the stability of the overall structure of the transformer, reduces the relative displacement between components when subjected to vibration or external impact, and protects the internal structure from damage.

[0054] A method for manufacturing a combined instrument transformer, used in any of the combined instrument transformers described in the embodiments, such as... Figure 8 As shown, including, Step S1, Injection molding: The first U-shaped conductor rod 4 and the second U-shaped conductor rod 5 are placed in the injection molds of the support body 12 and the lower shell 13, respectively. The support body 12 with plastic coating of the first U-shaped conductor rod and the lower shell 13 with plastic coating of the second U-shaped conductor rod are made by insert injection molding, and the upper cover 11 is injection molded. Step S2, one-time assembly: The first winding coil 2 and the second winding coil 3 are respectively installed into the upper end and lower end of the support body 12, and the first single arm of the first U-shaped conductor rod 4 passes through the inner circle of the first winding coil 2. Step S3, pin welding: After passing through the wire groove 127, the wire ends of the first winding coil 2 and the second winding coil 3 are welded to the pins 6 one by one, and the pins 6 are snapped into the pin groove 128 and the snap fastener 129 of the support body 12 to obtain the first assembly. Step S4, Secondary assembly: The first assembly obtained in step S3 is inserted into the lower housing 13, and the first single arm of the second U-shaped conductor rod 5 is inserted through the inner ring of the first winding coil 2 and the inner ring of the second winding coil 3 to obtain the second assembly. Step S5, potting: Pour the liquid insulating adhesive into the second assembly obtained in step S4, and install the top cover 11 after the insulating adhesive has completely cured.

[0055] The first U-shaped conductor rod 4 of the present invention is fixedly connected to the support body 12 by means of insert injection molding; the second U-shaped conductor rod 5 is fixedly connected to the lower shell 13 by means of insert injection molding; the first U-shaped conductor rod 4 and the second U-shaped conductor rod 5 are both located in a closed structure except for the top end.

[0056] The present invention directly injection molds the first U-shaped conductor rod 4 and the second U-shaped conductor rod 5 into the housing 1, making assembly simpler and more convenient, and helping to realize automated production.

[0057] Specifically, the first U-shaped conductor rod 4 and the second U-shaped conductor rod 5 are fixed to the support body 12 and the lower housing 13 by insert injection molding, so that the part except the top is wrapped with insulating material. This can enhance the connection stability between the U-shaped conductor rod and the housing 1, and the housing 1 or the insulating colloid can form a certain insulating barrier between the conductor rod and the winding coil, so as to avoid the adverse phenomenon of withstand voltage breakdown between the conductor rod and the winding coil and ensure the safety performance of the transformer.

[0058] Specifically, the first single arm of the first U-shaped conductor rod 4 passes through the inner ring of the first winding coil 2 and extends out of the housing 1 at its end. The part of it that passes through the first central column 121 is tightly fitted with the support body 12, and the other single arm is placed in the annular groove 133 of the lower housing 13, serving as the primary side port of the first winding coil 2 in the entire transformer, and participating in the electromagnetic induction process.

[0059] Specifically, the single arm of the second U-shaped conductor rod 5 passes through the inner rings of the first winding coil 2 and the second winding coil 3 in sequence, with its end extending out of the housing 1. Except for the top end, the rest of the part passes through the U-shaped through slot of the lower housing 13, and through the through hole 126 of the support body 12 to provide a primary side port for the second winding coil 3, thereby realizing the current measurement function.

[0060] This invention integrates the design and fabrication of two types of current transformers, which reduces the space occupied by the product, is more conducive to the miniaturization and integration of electronic devices, significantly shortens the manufacturing process, simplifies the manufacturing steps, and greatly reduces manufacturing costs. By placing the two winding coils in the same housing, the problem of poor connection stability of simple stacked current transformers in the prior art is solved, which greatly improves the safety and reliability of the current transformer and its circuit.

[0061] In a preferred embodiment, In step S2, the first winding coil 2 and the second winding coil 3 are prepared by selecting a first toroidal magnetic core and winding enameled wire with a preset number of turns and groups on the first toroidal magnetic core to obtain the first winding coil 2; selecting a second toroidal magnetic core and winding enameled wire with a preset number of turns on the second toroidal magnetic core to obtain the second winding coil 3.

[0062] Specifically, the pin 6 of the present invention is connected to the ends of the first coil and the second coil and is snapped into the pin groove 128. The pin 6 is provided with a pin buckle 61, which matches the snap-fit ​​buckle 129 on the side of the support body 12 near the pin groove 128, for fixing the pin 6 and ensuring a stable connection between the winding coil and the external circuit.

[0063] Specifically, this invention integrates power metering and leakage protection functions into a single transformer. Compared to traditional separate power metering and leakage protection transformers, this reduces the product's footprint, achieves device miniaturization, and the integrated manufacturing process significantly shortens the manufacturing process, simplifies manufacturing procedures, and greatly reduces manufacturing costs. The support body 12 supports and fixes the first winding coil 2 and the second winding coil 3, allowing the first winding coil 2 and the second winding coil 3 to be stably placed inside the housing 1 without contacting each other, ensuring the normal operation of the transformer and guaranteeing the safety and reliability of the transformer and its circuit.

[0064] The above description is merely a preferred embodiment of the present invention and does not limit the implementation and protection scope of the present invention. Those skilled in the art should realize that any equivalent substitutions and obvious changes made based on the description and illustrations of the present invention should be included within the protection scope of the present invention.

Claims

1. A combined current transformer, characterized in that, include, A shell (1); The first winding coil (2) and the second winding coil (3) are stacked in the housing (1) and are located on the upper and lower ends of a support (12) in the housing (1), respectively. A first U-shaped conductor rod (4) and a second U-shaped conductor rod (5) are arranged in parallel. The first single arm of the first U-shaped conductor rod (4) passes through the inner circle of the first winding coil (2) and the end extends out of the housing (1). The first single arm of the second U-shaped conductor rod (5) passes through the inner circle of the first winding coil (2) and the inner circle of the second winding coil (3) and the end extends out of the housing (1). A set of parallel output pins (6) are electrically connected to the ends of the first winding coil (2) and the second winding coil (3), and all of them extend out of the housing (1).

2. The combined current transformer according to claim 1, characterized in that, The upper end of the support (12) includes, The first central column (121) has an internal hollow structure. The first single arm of the first U-shaped conductor rod (4) passes through the first central column (121). The height of the first central column (121) is not less than the height of the first winding coil (2). The first arc plate (122) is set at a certain distance on the side of the first central column (121). The arc of the first arc plate (122) is adapted to the inner ring of the first winding coil (2). The inner ring of the first winding coil (2) can be connected to the ground on the first central column (121) and the first arc plate (122). A baffle (123) is disposed between the outer ring of the first winding coil (2) and the second single arm of the first U-shaped conductor rod (4).

3. The combined current transformer according to claim 1, characterized in that, The lower end of the support (12) includes, The second arc plate (124) is located on the ring side of the bottom end of the first U-shaped conductor rod (4), and the inner ring of the second winding coil (3) can be grounded and connected to the second arc plate (124). A limiting block (125) is provided on the outer ring side of the second arc plate (124). One end of the second winding coil (3) abuts against the limiting block (125). The height of the limiting block (125) is not less than the height of the bottom protrusion of the first U-shaped conductor rod (4).

4. The combined current transformer according to claim 1, characterized in that, The support (12) also includes, A through hole (126) passes through the support body (12) and is located between the first winding coil (2) and the second winding coil (3). The first single arm of the second U-shaped conductor rod passes through the inner ring of the second winding coil (3), the through hole (126) and the inner ring of the first winding coil (2) from bottom to top. The wire channel (127) passes through the support body (12) and is located on the outer ring of the first winding coil (2) and the second winding coil (3) near the coil end. It is used to pass through the coil end of the first winding coil (2) and / or the coil end of the second winding coil (3). The pin slot (128) is located on the side near the wire slot (127). The number of pin slots (128) is the same as the total number of coil ends of the first winding coil (2) and the second winding coil (3). The coil ends of the first winding coil (2) and the coil ends of the second winding coil (3) are connected to the pin (6) and then inserted into the pin slot (128).

5. The combined current transformer according to claim 4, characterized in that, The housing (1) further includes an upper cover (11) and a lower housing (13). The upper cover (11) and the lower housing (13) form a sealed structure. The support (12) is located inside the sealed structure. The upper cover (11) is provided with a bayonet (112) for connecting the lower housing (13) near the edge of the lower housing (13). The upper cover (11) is provided with a lead-out groove (111) near the pin groove (128). After the pin (6) is inserted into the pin groove (128), it is led out to the outside of the upper cover (11) through the lead-out groove (111). The upper cover (11) is also provided with a lead-out hole (113) that runs through the upper and lower parts. The top ends of the first U-shaped conductor rod (4) and the second U-shaped conductor rod (5) pass through the lead-out hole (113) and lead out to the outside of the upper cover (11). The pin (6) is provided with a pin buckle (61), and the support body (12) is also provided with a snap buckle (129) that is compatible with the pin buckle (61) on the side near the pin groove (128).

6. The combined current transformer according to claim 5, characterized in that, The lower housing (13) includes, A slot (131) is provided on the edge of the lower housing (13) near the upper cover (11), and the slot (131) corresponds to the bayonet (112); The U-shaped through groove (132) has its first end located inside the lower housing (13) and its second end located at the edge of the lower housing (13). The second U-shaped conductor rod (5) is inserted into the U-shaped through groove (132) except for its two ends. The first end of the U-shaped through groove (132) passes through the through hole (126). An annular groove (133) is provided at the edge of the lower housing (13) near the side of the first U-shaped conductor rod (4), and the second single arm of the first U-shaped conductor rod (4) is provided in the annular groove (133).

7. The combined current transformer according to claim 1, characterized in that, The first winding coil (2) includes a first toroidal core and at least one set of first coils wound on the first toroidal core; the second winding coil (3) includes a second toroidal core and a second coil wound on the second toroidal core.

8. The combined current transformer according to claim 1, characterized in that, It also includes an insulating colloid that fills the housing (1) and covers the periphery of the first winding coil (2), the second winding coil (3), the first U-shaped conductor rod (4), the second U-shaped conductor rod (5), the output pin (6), and the support body (12).

9. A method for manufacturing a combined current transformer, characterized in that, For manufacturing the combined current transformer as described in any one of claims 1-8, comprising: Step S1, Injection molding: The first U-shaped conductor rod (4) and the second U-shaped conductor rod (5) are placed in the injection molds of the support body (12) and the lower shell (13) respectively, and the support body (12) with plastic coating of the first U-shaped conductor rod and the lower shell (13) with plastic coating of the second U-shaped conductor rod are obtained by insert injection molding, and the top cover (11) is obtained by injection molding. Step S2, one-time assembly: the first winding coil (2) and the second winding coil (3) are respectively installed into the upper end and lower end of the support body (12), and the first single arm of the first U-shaped conductor rod (4) passes through the inner ring of the first winding coil (2); Step S3, pin welding: After passing through the wire groove (127), the wire ends of the first winding coil (2) and the second winding coil (3) are welded to the pins (6) one by one, and the pins (6) are inserted into the pin groove (128) and the snap fastener (129) of the support body (12) to obtain the first assembly; Step S4, Secondary assembly: The first assembly obtained in step S3 is inserted into the lower housing (13), and the first single arm of the second U-shaped conductor rod (5) is inserted through the inner ring of the first winding coil (2) and the inner ring of the second winding coil (3) to obtain the second assembly; Step S5, potting: Pour liquid insulating adhesive into the second assembly obtained in step S4, and install the top cover (11) after the insulating adhesive has completely cured.

10. The method for preparing the combined current transformer according to claim 9, characterized in that, In step S2, the first winding coil (2) and the second winding coil (3) are prepared by selecting a first toroidal magnetic core and winding a preset number of turns and groups of enameled wire on the first toroidal magnetic core to obtain the first winding coil (2); selecting a second toroidal magnetic core and winding a preset number of turns of enameled wire on the second toroidal magnetic core to obtain the second winding coil (3).

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