Fixing device and planar transformer

Abstract

The invention provides a fixing device and a planar transformer, and the fixing device comprises a first fixing part which is provided with a first isolation column, a first substrate and a pair of first arc-shaped skeletons, and a first PCB winding in the planar transformer sleeves the first isolation column and is located between the pair of first arc-shaped skeletons; at the moment, the first PCB winding is isolated from a first magnetic core in the planar transformer; the second fixing part is provided with a second isolation column, a second substrate and a pair of second arc-shaped frameworks, a second PCB winding of the planar transformer is arranged on the second isolation column in a sleeving mode and located between the pair of second arc-shaped frameworks, and at the moment, the second PCB winding is isolated from a second magnetic core in the planar transformer; when the two magnetic cores are connected, the end, away from the first substrate, of the first isolation column abuts against the end, away from the second substrate, of the second isolation column, so that the first PCB winding and the second PCB winding are isolated from each other. According to the fixing device, the first PCB winding and the second PCB winding can be effectively isolated from the magnetic core, so that the safety requirement is met.

Description

Technical Field

[0001] The present application relates to the technical field of planar transformers, and in particular to a fixing device with an insulating function and a planar transformer comprising the fixing device. Background Art

[0002] In the product design of micro-inverters, transformers are often used to convert energy between high and low voltages, especially low-cost planar transformers. Moreover, while achieving high and low voltage energy conversion, planar transformers must also meet safety distance requirements between the high and low voltages.

[0003] In the prior art, due to the limitations of the winding window of the magnetic core itself, traditional planar transformers usually manufacture the high-voltage side PCB winding (the high-voltage side PCB winding is also the second PCB winding) into a multi-layer PCB module (PCB, or printed circuit board) with no surface wiring. In this case, the layers are interconnected through buried vias. At the same time, the multi-layer PCB module (the multi-layer PCB module includes at least two layers of first PCB modules 2001 for the first PCB winding and at least two layers of second PCB modules 3001 for the second PCB winding) is certified for solid insulation to meet distance requirements. However, this design not only has the disadvantage of a long project cycle, but also traditional planar transformers using this design have no cost advantage compared to traditional transformers.

[0004] In summary, traditional planar transformers cannot achieve isolation between the high-voltage side PCB winding and the low-voltage side winding, isolation between the high-voltage side PCB winding and the second magnetic core on the high-voltage side, and isolation between the low-voltage side PCB winding and the first magnetic core on the low-voltage side. In addition, the existing fixing device cannot wrap around the high-voltage side PCB winding. Therefore, the existing fixing device is difficult to ensure isolation between the high-voltage side PCB winding and the magnetic core, resulting in the high-voltage side PCB winding failing to meet the safety requirements of double insulation (or reinforced insulation). Summary of the Invention

[0005] The fixing device and planar transformer provided in the present application are intended to address at least some of the defects of conventional fixing devices and existing planar transformers having conventional fixing devices.

[0006] In a first aspect, the present application provides a fixing device. The fixing device is applied to a planar transformer having a first PCB winding, a second PCB winding, and two magnetic cores, wherein the magnetic core has a bottom plate, a center column, and a pair of arc-shaped bone walls, and the fixing device includes:

[0007] A first fixing component includes a hollow first isolation column, a first substrate, and a pair of first arc-shaped skeletons. The first PCB winding is sleeved on the first isolation column and located between the pair of first arc-shaped skeletons. The center column of the first magnetic core of the two magnetic cores can be inserted into the hollow area of ​​the first isolation column. When the center column of the first magnetic core is inserted into the hollow area of ​​the first isolation column, the outer surface of the first arc-shaped skeleton abuts the inner surface of the arc-shaped skeleton wall of the first magnetic core, and the first substrate abuts the bottom plate of the first magnetic core.

[0008] The second fixing component includes a hollow second isolation column, a second base plate, and a pair of second arc-shaped frames. The second PCB winding is mounted on the second isolation column and located between the pair of second arc-shaped frames. The middle column of the second magnetic core of the two magnetic cores is inserted into the hollow area of ​​the second isolation column. When the middle column of the second magnetic core is inserted into the hollow area of ​​the second isolation column, the outer surface of the second arc-shaped frame abuts the inner surface of the arc-shaped frame wall of the second magnetic core, and the second base plate abuts the bottom plate of the second magnetic core.

[0009] When the two magnetic cores are connected to each other along their axial directions, one end of the first isolation column away from the first substrate and one end of the second isolation column away from the second substrate abut against each other;

[0010] The inner surface of the arc-shaped bone wall has a preset first arc length, the outer surface of the second arc-shaped skeleton has a preset second arc length, and the first arc length is smaller than the second arc length.

[0011] In some embodiments, a pair of the first arc-shaped skeletons are both coaxially arranged with the first isolation column;

[0012] The first isolation column protrudes from the first substrate, and the first isolation column and the first substrate are coaxially arranged;

[0013] Each of the first arc-shaped skeletons is provided with a first inclined surface and a first slot on its radial inner side, and the first inclined surface can guide the first PCB winding into the first slot to limit the first PCB winding from escaping from the first fixing component.

[0014] In some embodiments, a first predetermined distance is formed between the first inclined surface at one end of the first slot and the outer cylindrical surface of the first isolation column in the radial direction of the first arc-shaped skeleton;

[0015] An end of the first inclined surface away from the first slot and an outer cylindrical surface of the first isolation column have a preset second distance in the radial direction of the first arc-shaped skeleton;

[0016] The first spacing is smaller than the second spacing.

[0017] In some embodiments, a pair of the second arc-shaped skeletons are both coaxially arranged with the second isolation column;

[0018] The second isolation column protrudes from the second substrate, and the second isolation column is coaxially arranged with the second substrate;

[0019] Each of the second arc-shaped frames is provided with a second inclined surface and a second slot on its radial inner side, and the second inclined surface can guide the second PCB winding into the second slot to limit the second PCB winding from escaping from the second fixing component.

[0020] In some embodiments, a preset third distance is formed between the second inclined surface at one end of the second slot and the outer cylindrical surface of the second isolation column in the radial direction of the second arc-shaped skeleton;

[0021] A fourth preset distance is formed between an end of the second inclined surface away from the second slot and an outer cylindrical surface of the second isolation column in the radial direction of the second arc-shaped skeleton;

[0022] The third interval is smaller than the fourth interval.

[0023] In some embodiments, each of the first arc-shaped frames is provided with a mounting groove along its outer side radially away from the first isolation column, and the mounting groove is located at an end of the first arc-shaped frame axially away from the first substrate;

[0024] Each second arc-shaped frame is provided with a clamping member adapted to the mounting groove on its outer side in the radial direction away from the second isolation column, and the clamping member protrudes from an end of the second arc-shaped frame in the axial direction away from the second substrate;

[0025] The installation slot is opened at a position corresponding to the setting position of the clamping member, and the second fixing member and the first fixing member are fixedly connected by the mutual engagement of the clamping member and the installation slot.

[0026] In some embodiments, a plurality of first arc-shaped protrusions are provided in the hollow area of ​​the first isolation column;

[0027] When the middle column of the first magnetic core is inserted into the hollow area of ​​the first isolation column, the first arc-shaped protrusion abuts against the outer cylindrical surface of the first isolation column to prevent the first magnetic core and the first fixing component from separating from each other.

[0028] In some embodiments, a plurality of second arc-shaped protrusions are provided in the hollow area of ​​the second isolation column;

[0029] When the middle column of the second magnetic core is inserted into the hollow area of ​​the second isolation column, the second arc-shaped protrusion abuts against the outer cylindrical surface of the second isolation column to prevent the second magnetic core and the second fixing component from separating from each other.

[0030] In some embodiments, when the first fixing member is fixedly connected to the second fixing member, the pair of the first arc-shaped frames and the pair of the second arc-shaped frames enclose and form an isolation space with a gap;

[0031] When the two magnetic cores are connected to each other along their axial directions, the two pairs of arc-shaped bone walls enclose a receiving space, and both the first fixing component and the second fixing component are located in the receiving space;

[0032] The first PCB winding and the second PCB winding are both located inside the isolation space, and at least parts of the first PCB winding and the second PCB winding can extend through the gap to the outside of the isolation space.

[0033] In a second aspect, the present application provides a planar transformer. The planar transformer comprises:

[0034] Two magnetic cores with a central column, a first PCB winding, a second PCB winding and the above-mentioned fixing device;

[0035] The first PCB winding is sleeved on the first fixing component of the fixing device, and the second PCB winding is sleeved on the second fixing component of the fixing device;

[0036] The first magnetic core of the two magnetic cores is fixedly connected to the first fixing component, and the second magnetic core of the two magnetic cores is fixedly connected to the second fixing component. In this case, the first PCB winding and the second PCB winding can be isolated from the two magnetic cores by the fixing device.

[0037] An air gap is provided between the two middle columns of the two magnetic cores, and the first PCB winding and the second PCB winding are both away from the air gap along the axial direction of the magnetic core.

[0038] At least one beneficial effect of the fixing device and planar transformer provided in the embodiments of the present application is: providing an internally insulated fixing device for fixing or accommodating a first PCB winding and a second PCB winding, and a planar transformer having the fixing device; wherein, the fixing device can effectively achieve isolation between the first PCB winding and the second PCB winding, isolation between the first PCB winding and the first magnetic core, and isolation between the second PCB winding and the second magnetic core, thereby meeting safety requirements; in addition, the fixing device can wrap around the second PCB winding, so that the second PCB winding can further meet the safety requirements of double insulation (or reinforced insulation). BRIEF DESCRIPTION OF THE DRAWINGS

[0039] One or more embodiments are exemplarily illustrated by corresponding drawings, which do not constitute limitations on the embodiments. Elements with the same reference numerals in the drawings are represented as the same elements, and unless otherwise stated, the figures in the drawings do not constitute proportional limitations.

[0040] Figure 1 A schematic diagram of the structure of a planar transformer provided in an embodiment of the present application;

[0041] Figure 2 This is an exploded diagram of the structure of the planar transformer provided in an embodiment of the present application;

[0042] Figure 3 A schematic cross-sectional view of a planar transformer provided in an embodiment of the present application;

[0043] Figure 4 Provided in the embodiments of this application Figure 3 A local enlarged view at point A;

[0044] Figure 5 Provided in the embodiments of this application Figure 3 A partial enlarged view at point B;

[0045] Figure 6 Provided in the embodiments of this application Figure 3 A partial enlarged view at point C;

[0046] Figure 7 A schematic cross-sectional view of a fixing device provided in an embodiment of the present application;

[0047] Figure 8 A schematic structural diagram of a first fixing component provided in an embodiment of the present application;

[0048] Figure 9 A schematic structural diagram of the second fixing component provided in an embodiment of the present application.

[0049] Reference numerals:

[0050] 1000, planar transformer;

[0051] 100, fixing device; 101, notch; 1, first fixing component; 11, first substrate; 12, first arc-shaped frame; 13, first isolation column; 121, mounting slot; 122, first inclined surface; 123, first clamping slot; 131, first through hole; 1311, first arc-shaped protrusion; 2, second fixing component; 21, second substrate; 22, second arc-shaped frame; 23, second isolation column; 221, clamping member; 222, second inclined surface; 223, second clamping slot; 231, second through hole; 2311, second arc-shaped protrusion;

[0052] 200, first PCB winding; 2001, first PCB module;

[0053] 300, second PCB winding; 3001, second PCB module;

[0054] 400, magnetic core; 4001, first magnetic core; 4002, second magnetic core; 4003, bottom plate; 4004, middle column; 4005, curved bone wall. DETAILED DESCRIPTION

[0055] The present application is described in detail below with reference to specific embodiments. It should be emphasized that the following description is merely illustrative and is not intended to limit the scope of the present application and its applications.

[0056] It should be noted that, unless otherwise expressly specified and limited, the terms "located", "away from", "axial", "radial", etc. used in this specification to indicate the orientation or position relationship are based on the orientation or position relationship shown in the accompanying drawings, and are only for the convenience of describing this application and simplifying the description, and do not indicate or imply 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 application. Terms such as "installation", "fitting", "connection" and "fixation" should be understood in a broad sense. For example, "connection" can be a fixed connection or a detachable connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium; "fixation" can be bolt fixation, snap fixation, or glue fixation; the terms "first", "second", "third" and "fourth" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated; thus, the features limited to "first", "second", "third" and "fourth" may explicitly or implicitly include one or more of such features; "multiple" or "several" means two or more; in addition, "and / or" includes any and all combinations of one or more related listed items; for ordinary technicians in this field, the specific meanings of the above terms in this application can be understood according to the specific circumstances.

[0057] In order to make the objectives, technical solutions and advantages of this application clearer, this application is described in detail below with reference to the accompanying drawings and specific embodiments.

[0058] In this embodiment, the specific implementation of the "fixing device and the planar transformer" is not limited, and those skilled in the art can selectively use any appropriate implementation method according to actual needs.

[0059] Figure 1This is a schematic diagram of the structure of the planar transformer provided in an embodiment of the present application. Figure 2 This is a structural exploded diagram of the planar transformer provided in an embodiment of the present application. Figure 3 A schematic cross-sectional view of a planar transformer according to an embodiment of the present application. Figure 4 Provided in the embodiments of this application Figure 3 A partial enlarged view of point A. Figure 5 Provided in the embodiments of this application Figure 3 A partial enlarged view at point B. Figure 6 Provided in the embodiments of this application Figure 3 A partial enlarged view at point C. Figure 7 A schematic cross-sectional view of a fixing device provided in an embodiment of the present application. Figure 8 A schematic structural diagram of the first fixing component provided in an embodiment of the present application. Figure 9 A schematic structural diagram of the second fixing component provided in an embodiment of the present application.

[0060] See also Figures 1-9 The fixing device 100 is applied to a planar transformer 1000 having a first PCB winding 200, a second PCB winding 300 and two magnetic cores 400, and the magnetic core 400 has a bottom plate 4003, a middle column 4004 and a pair of arc-shaped bone walls 4005.

[0061] It should be noted that in traditional transformers, high-voltage coils (high-voltage coils are located on the high-voltage side of traditional transformers, used to receive high-voltage and low-current input power, and then convert the high-voltage and low-current input power into low-voltage and high-current output power through electromagnetic induction) usually use multiple layers of insulated wires and insulating pads to achieve insulation between the traditional magnetic core and low-voltage coils (low-voltage coils are located on the low-voltage side of traditional transformers, used to receive low-voltage and high-current output power), thereby meeting the double insulation requirements (or reinforced insulation requirements) between high and low voltages.

[0062] Generally speaking, multi-layer insulated wire is usually used to wind high-voltage coils and low-voltage coils of traditional transformers. The insulated wire consists of a core wire and an insulation layer. These insulation layers are tightly wrapped around the core wire to form the first solid insulation barrier.

[0063] To further illustrate, the insulating pad can be placed between the multiple layers of insulating wires of the high-voltage coil to form inter-layer insulation; and, for a traditional transformer with multi-turn windings, the insulating pad can also be placed between the multi-turn windings to form inter-turn insulation; in summary, the multi-layer insulating wires and insulating pads can achieve the double insulation requirements (or enhanced insulation requirements) between the high-voltage coil and the traditional magnetic core, and can also achieve the double insulation requirements (or enhanced insulation requirements) between the high-voltage coil and the low-voltage coil.

[0064] However, due to winding and insulation reasons, traditional transformers cannot be made as low as planar transformers, resulting in an increase in the overall height of the product and increased structural costs. In addition, the entire product cavity needs to be filled with glue to dissipate heat, which increases the cost of filling the glue. The cost of traditional transformers is higher than that of planar transformers.

[0065] Therefore, under the constraints of market competition and product appearance characteristics, more and more manufacturers are using planar transformers to replace traditional transformers; specifically, planar transformers use PCB windings to replace the coil windings made of multi-layer insulated wires used in traditional transformers, thereby reducing costs.

[0066] In summary, during the design of a planar transformer, it is necessary to solve the technical problem that the safety distance between the high and low voltages is difficult to meet in order to meet the double insulation requirements (or reinforced insulation requirements).

[0067] In the embodiment of the present application, the middle column 4004 and the pair of curved bone walls 4005 both protrude from the bottom plate 4003, the pair of curved bone walls 4005 are both coaxially arranged with the middle column 4004, and the middle column 4004 and the bottom plate 4003 are coaxially arranged; it can be understood that the bottom plate 4003 of the magnetic core 400 is a circular plate with both sides cut off, and the pair of curved bone walls 4005 of the magnetic core 400 can be regarded as a circular ring structure with both sides cut off; the second base plate 21 is a complete circular plate, and the second curved skeleton 22 is a circular ring structure with a pair of notches; the first curved skeleton 12 is also a circular ring structure with a pair of notches.

[0068] It should be noted that the two magnetic cores include a first magnetic core 4001 located on the low-voltage side of the planar transformer 1000 and a second magnetic core 4002 located on the high-voltage side of the planar transformer 1000 .

[0069] The fixing device 100 mentioned above includes a first fixing component 1 and a second fixing component 2 .

[0070] Specifically, the fixing device 100 is made of a material having an insulating function, such as plastic, so that the fixing device 100 itself has an insulating function.

[0071] The first fixing component 1 includes a hollow first isolation column 13 , a first substrate 11 and a pair of first arc-shaped frames 12 .

[0072] In addition, the first PCB winding 200 is sleeved on the first isolation column 13 and is located between a pair of first arc-shaped skeletons 12. The middle column 4004 of the first magnetic core 4001 of the two magnetic cores 400 can be inserted into the hollow area of ​​the first isolation column 13. When the middle column 4004 of the first magnetic core 4001 is inserted into the hollow area of ​​the first isolation column 13, the outer surface of the first arc-shaped skeleton 12 abuts against the inner surface of the arc-shaped bone wall 4005 of the first magnetic core 4001, and the first substrate 11 abuts against the bottom plate 4003 of the first magnetic core 4001, so that the first PCB winding 200 and the first magnetic core 4001 are isolated from each other, thereby meeting safety requirements.

[0073] In addition, the second fixing component 2 includes a hollow second isolation column 23, a second substrate 21 and a pair of second arc-shaped frames 22. The second PCB winding 300 is sleeved on the second isolation column 23 and is located between the pair of second arc-shaped frames 22. The middle column 4004 of the second magnetic core 4002 of the two magnetic cores 400 is inserted into the hollow area of ​​the second isolation column 23. When the middle column of the second magnetic core is inserted into the hollow area of ​​the second isolation column, the outer surface of the second arc-shaped frame 22 abuts against the inner surface of the arc-shaped bone wall 4005 of the second magnetic core 4002 and the second substrate 21 abuts against the bottom plate 4003 of the second magnetic core 4002, so that the second PCB winding 300 and the second magnetic core 4002 are isolated from each other, thereby meeting safety requirements.

[0074] In the embodiment of the present application, the hollow area includes a first through hole 131 penetrating the first substrate 11 and the first isolation column 13 , and a second through hole 231 penetrating the second substrate 21 and the second isolation column 23 .

[0075] In addition, the hollow first isolation column 13 and the hollow second isolation column 23 also have an insulation function, so that a reliable insulation barrier is formed between the first PCB winding 200 and the second PCB winding 300 and the middle columns 4004 of the two magnetic cores 400 respectively.

[0076] It should be noted that when the two magnetic cores 400 are connected to each other along their axial direction, the end of the first isolation column 13 away from the first substrate 11 and the end of the second isolation column 23 away from the second substrate 21 abut against each other, so that the first PCB winding 200 and the second PCB winding 300 are isolated from each other.

[0077] It can be understood that the inner surface of the arc-shaped bone wall 4005 has a preset first arc length, the outer surface of the second arc-shaped skeleton 22 has a preset second arc length, and the first arc length is smaller than the second arc length.

[0078] It is further explained that the outer surface of the first arc-shaped skeleton 12 has a preset third arc length, and the third arc length can be smaller than the above-mentioned first arc length; in the embodiment of the present application, it is only necessary to ensure that ordinary insulation is not short-circuited between the first PCB winding 200 and the first magnetic core 4001.

[0079] Specifically, the first PCB winding is arranged on the low-voltage side of the planar transformer 1000 , and the second PCB winding is arranged on the high-voltage side of the planar transformer 1000 .

[0080] In some embodiments, as Figure 2 、 Figure 7 and Figure 8 As shown, a pair of first arc-shaped frames 12 are both coaxially arranged with the first isolation column 13 .

[0081] The first isolation column 13 protrudes from the first substrate 11 , and the first isolation column 13 and the first substrate 11 are coaxially arranged.

[0082] In addition, each first arc-shaped skeleton 12 is provided with a first inclined surface 122 and a first slot 123 on its radial inner side, and the first inclined surface 122 can guide the first PCB winding 200 into the first slot 123 to limit the first PCB winding 200 from detaching from the first fixing component 1.

[0083] In addition, safety requirements mainly refer to a series of regulations and standards formulated to ensure the safe operation of equipment and the safety of personnel. These safety requirements generally include: planar transformers should ensure the electrical insulation performance of the equipment (for example, double insulation or reinforced insulation should be considered first during the design process of planar transformers to ensure that the equipment has excellent electrical insulation performance); in addition, these safety requirements also include: there should be sufficient safety distance between each PCB winding (for example, the distance between the first PCB winding 200 and the second PCB winding 300 in the planar transformer 1000) to prevent the planar transformer from short-circuiting during normal operation or fault conditions; in addition, these safety requirements also include: electrical clearance and creepage distance must meet relevant safety standards to prevent safety accidents caused by arc discharge or leakage.

[0084] Generally speaking, electrical clearance refers to the shortest spatial distance measured between two conductive parts or between a conductive part and the equipment protection interface; while creepage distance refers to the shortest distance between two conductive parts or between a conductive part and the equipment protection interface measured along the insulating surface.

[0085] In some embodiments, reference Figure 7 and Figure 8 It can be seen that a preset first distance exists between one end of the first inclined surface 122 located at the first locking groove 123 and the outer cylindrical surface of the first isolation column 13 in the radial direction of the first arc-shaped frame 12 .

[0086] It is understandable that a preset second distance exists between the end of the first inclined surface 122 away from the first locking groove 123 and the outer cylindrical surface of the first isolation column 13 in the radial direction of the first arc-shaped frame 12 .

[0087] It should be noted that the first spacing is smaller than the second spacing.

[0088] In some embodiments, combined Figure 2 、 Figure 7 and Figure 9 It can be seen that the pair of second arc-shaped frames 22 are both coaxially arranged with the second isolation column 23 .

[0089] The second isolation column 23 protrudes from the second substrate 21 , and the second isolation column 23 and the second substrate 21 are coaxially arranged.

[0090] In addition, each second arc-shaped skeleton 22 is provided with a second inclined surface 222 and a second slot 223 on its radial inner side, and the second inclined surface 222 can guide the second PCB winding 300 into the second slot 223 to limit the second PCB winding 300 from detaching from the second fixing component 2.

[0091] In some embodiments, Figure 7 and Figure 9 It can be seen that a preset third distance exists between one end of the second inclined surface 222 located at the second locking groove 223 and the outer cylindrical surface of the second isolation column 23 in the radial direction of the second arc-shaped frame 22 .

[0092] In the embodiment of the present application, a predetermined fourth distance is formed between an end of the second inclined surface 222 away from the second locking groove 223 and an outer cylindrical surface of the second isolation column 23 in the radial direction of the second arc-shaped frame 22 .

[0093] Specifically, the third interval is smaller than the fourth interval.

[0094] In some embodiments, according to Figure 2-Figure 9 It can be seen that each first arc-shaped frame 12 has a mounting groove 121 formed on its outer side radially away from the first isolation column 13 , and the mounting groove 121 is located at one end of the first arc-shaped frame 12 axially away from the first substrate 11 .

[0095] Each second arc-shaped frame 22 is provided with a clamping member 221 adapted to the mounting groove 121 on its outer side radially away from the second isolation column 23 , and the clamping member 221 protrudes from one end of the second arc-shaped frame 22 axially away from the second substrate 21 .

[0096] In addition, the opening position of the installation groove 121 corresponds to the setting position of the clamping member 221 , and the second fixing component 2 and the first fixing component 1 are fixedly connected by the mutual engagement of the clamping member 221 and the installation groove 121 .

[0097] To further illustrate, the clip 221 and the second arc-shaped frame 22 are an integrally formed structure, that is, the clip 221 is made of a plastic material with deformation ability; at this time, the clip 221 is inserted into the installation groove 121 through its own deformation until it reaches the specified position and is automatically clamped and fixed, thereby forming a reliable snap-fit ​​fixation between the second fixing component 2 and the first fixing component 1; specifically, during the process of inserting the clip 221 into the installation groove 121, if the assembler hears a click sound, it can be considered that the clip 221 has reached the above-mentioned specified position.

[0098] In some embodiments, please refer to Figure 2 and Figure 7 A plurality of first arc-shaped protrusions 1311 are provided in the hollow area of ​​the first isolation column 13 .

[0099] Specifically, when the middle column 4004 of the first magnetic core 4001 is inserted into the hollow area of ​​the first isolation column 13 , the first arc-shaped protrusion 1311 abuts against the outer cylindrical surface of the first isolation column 13 to prevent the first magnetic core 4001 and the first fixing component 1 from separating from each other.

[0100] In some embodiments, please refer to Figure 2 and Figure 7 A plurality of second arc-shaped protrusions 2311 are provided in the hollow area of ​​the second isolation column 23 .

[0101] It should be noted that when the middle column 4004 of the second magnetic core 4002 is inserted into the hollow area of ​​the second isolation column 23, the second arc-shaped protrusion 2311 abuts against the outer cylindrical surface of the second isolation column 23 to prevent the second magnetic core 4002 and the second fixing component 2 from separating from each other.

[0102] It can be understood that the first arc-shaped protrusion 1311 protrudes from the inner surface of the first through hole 131 along the radial direction of the first through hole 131 and can be semi-cylindrical; and the second arc-shaped protrusion 2311 protrudes from the inner surface of the second through hole 231 along the radial direction of the second through hole 231 and can also be semi-cylindrical.

[0103] In some embodiments, as Figure 1-Figure 7 As shown, when the first fixing component 1 is fixedly connected to the second fixing component 2 , a pair of first arc-shaped frames 12 and a pair of second arc-shaped frames 22 enclose and form an isolation space with a gap 101 .

[0104] When the two magnetic cores 400 are connected to each other along their axial directions, the two pairs of arc-shaped bone walls enclose and form an accommodation space, and the first fixing component 1 and the second fixing component 2 are both located in the accommodation space.

[0105] In addition, the first PCB winding 200 and the second PCB winding 300 are both located inside the isolation space, and at least parts of the first PCB winding 200 and the second PCB winding 300 can pass through the gap 101 and extend to the outside of the isolation space.

[0106] See also Figures 1-9 The planar transformer 1000 includes: two magnetic cores 400 with a center column 4004, a first PCB winding 200, a second PCB winding 300 and the above-mentioned fixing device 100.

[0107] The first PCB winding 200 is sleeved on the first fixing component 1 of the fixing device 100 , and the second PCB winding 300 is sleeved on the second fixing component 2 of the fixing device 100 .

[0108] In addition, the first magnetic core 4001 of the two magnetic cores 400 is fixedly connected to the first fixing part 1, and the second magnetic core 4002 of the two magnetic cores 400 is fixedly connected to the second fixing part 2. At this time, the first PCB winding 200 and the second PCB winding 300 can be isolated from each other by the fixing device 100.

[0109] In addition, an air gap is provided between the two middle columns 4004 of the two magnetic cores 400 , and both the first PCB winding 200 and the second PCB winding 300 are away from the air gap along the axial direction of the magnetic core 400 .

[0110] In the embodiment of the present application, the planar transformer 1000 can control the leakage inductance of the planar transformer 1000 by controlling the first distance between the first PCB winding 200 and the second PCB winding 300, thereby achieving the purpose of integrated resonant inductance.

[0111] Specifically, the air gap usually refers to the gap between the two middle columns 4004 in the two magnetic cores 400 at the joint, which is used to prevent magnetic saturation; wherein, if the PCB winding (the PCB winding includes the first PCB winding 200 or the low-voltage side PCB winding, and the second PCB winding 300 or the high-voltage side PCB winding) is placed near the air gap at the connection of the two middle columns 4004 in the two magnetic cores 400, it will cause the eddy current loss of the planar transformer 1000 to increase, and the heat generation will increase at the same time, thereby greatly affecting the performance of the planar transformer 1000; therefore, when the first PCB winding 200 and the second PCB winding 300 are away from the air gap, the loss and heat generation of the planar transformer 1000 can be effectively reduced, thereby improving the performance of the planar transformer 1000.

[0112] To further illustrate, the first PCB winding 200 and the second PCB winding 300 are both composed of multi-layer PCB modules; wherein the multi-layer PCB module includes at least two layers of first PCB modules 2001 of the first PCB winding 200 and at least two layers of second PCB modules 3001 of the second PCB winding 300.

[0113] It should be noted that the fixing device 100 can be used to fix or accommodate the first PCB winding 200 and the second PCB winding 300. Therefore, the fixing device 100 can be used as a welding jig to ensure the quality of the inter-board interconnection welding between the first PCB winding and the second PCB winding, so as to achieve reliable fixation of the multi-layer PCB module.

[0114] In the embodiment of the present application, the surface layers of the first PCB winding 200 and the second PCB winding 300 can be designed with routing, and buried vias are not required between layers, thereby reducing the cost of the first PCB winding 200 and the second PCB winding 300. At the same time, the insulating pads between the first PCB winding 200 and the first magnetic core 4001, the second magnetic core 4002 and the second PCB winding 300 are also saved, so that the production cost of the planar transformer 1000 can be further reduced while meeting safety requirements.

[0115] In summary, the embodiments of the present application provide an internally insulated fixture for fixing or accommodating a first PCB winding and a second PCB winding, as well as a planar transformer having the fixture. The fixture can effectively isolate the first PCB winding from the second PCB winding, isolate the first PCB winding from the first magnetic core, and isolate the second PCB winding from the second magnetic core to meet safety regulations. Furthermore, the fixture can wrap around the second PCB winding, so that the second PCB winding can further meet safety regulations for double insulation (or reinforced insulation).

[0116] The above content is a further detailed description of the present application in conjunction with specific / preferred embodiments, and it cannot be determined that the specific implementation of the present application is limited to these descriptions. For those skilled in the art, various modifications and improvements can be made without departing from the concept of the present application, and these are all within the scope of protection of the present application.

Claims

1. A fixing device for a planar transformer having a first PCB winding, a second PCB winding and two magnetic cores, wherein the magnetic core has a bottom plate, a middle column and a pair of arc-shaped bone walls, characterized in that: The fixing device comprises: A first fixing component includes a hollow first isolation column, a first substrate, and a pair of first arc-shaped skeletons. The first PCB winding is sleeved on the first isolation column and located between the pair of first arc-shaped skeletons. The center column of the first magnetic core of the two magnetic cores can be inserted into the hollow area of ​​the first isolation column. When the center column of the first magnetic core is inserted into the hollow area of ​​the first isolation column, the outer surface of the first arc-shaped skeleton abuts the inner surface of the arc-shaped skeleton wall of the first magnetic core, and the first substrate abuts the bottom plate of the first magnetic core. The second fixing component includes a hollow second isolation column, a second base plate, and a pair of second arc-shaped frames. The second PCB winding is mounted on the second isolation column and located between the pair of second arc-shaped frames. The middle column of the second magnetic core of the two magnetic cores is inserted into the hollow area of ​​the second isolation column. When the middle column of the second magnetic core is inserted into the hollow area of ​​the second isolation column, the outer surface of the second arc-shaped frame abuts the inner surface of the arc-shaped frame wall of the second magnetic core, and the second base plate abuts the bottom plate of the second magnetic core. When the two magnetic cores are connected to each other along their axial directions, one end of the first isolation column away from the first substrate and one end of the second isolation column away from the second substrate abut against each other; The inner surface of the arc-shaped bone wall has a preset first arc length, the outer surface of the second arc-shaped skeleton has a preset second arc length, and the first arc length is smaller than the second arc length.

2. The fixing device according to claim 1, characterized in that A pair of the first arc-shaped frames are both coaxially arranged with the first isolation column; The first isolation column protrudes from the first substrate, and the first isolation column and the first substrate are coaxially arranged; Each of the first arc-shaped skeletons is provided with a first inclined surface and a first slot on its radial inner side, and the first inclined surface can guide the first PCB winding into the first slot to limit the first PCB winding from escaping from the first fixing component.

3. The fixing device according to claim 2, characterized in that There is a preset first distance between the first inclined surface located at one end of the first slot and the outer cylindrical surface of the first isolation column in the radial direction of the first arc-shaped skeleton; An end of the first inclined surface away from the first slot and an outer cylindrical surface of the first isolation column have a preset second distance in the radial direction of the first arc-shaped skeleton; The first spacing is smaller than the second spacing.

4. The fixing device according to claim 1, characterized in that A pair of the second arc-shaped frames are both coaxially arranged with the second isolation column; The second isolation column protrudes from the second substrate, and the second isolation column is coaxially arranged with the second substrate; Each of the second arc-shaped frames is provided with a second inclined surface and a second slot on its radial inner side, and the second inclined surface can guide the second PCB winding into the second slot to limit the second PCB winding from escaping from the second fixing component.

5. The fixing device according to claim 4, characterized in that A preset third distance is formed between the second inclined surface located at one end of the second slot and the outer cylindrical surface of the second isolation column in the radial direction of the second arc-shaped skeleton; A fourth preset distance is formed between an end of the second inclined surface away from the second slot and an outer cylindrical surface of the second isolation column in the radial direction of the second arc-shaped skeleton; The third interval is smaller than the fourth interval.

6. The fixing device according to claim 1, characterized in that Each of the first arc-shaped frames is provided with a mounting groove along its radially outer side away from the first isolation column, and the mounting groove is located at an end of the first arc-shaped frame away from the first substrate in its axial direction; Each second arc-shaped frame is provided with a clamping member adapted to the mounting groove on its outer side in the radial direction away from the second isolation column, and the clamping member protrudes from an end of the second arc-shaped frame in the axial direction away from the second substrate; The installation slot is opened at a position corresponding to the setting position of the clamping member, and the second fixing member and the first fixing member are fixedly connected by the mutual engagement of the clamping member and the installation slot.

7. The fixing device according to claim 1, characterized in that A plurality of first arc-shaped protrusions are provided in the hollow area of ​​the first isolation column; When the middle column of the first magnetic core is inserted into the hollow area of ​​the first isolation column, the first arc-shaped protrusion abuts against the outer cylindrical surface of the first isolation column to prevent the first magnetic core and the first fixing component from separating from each other.

8. The fixing device according to claim 1, characterized in that A plurality of second arc-shaped protrusions are provided in the hollow area of ​​the second isolation column; When the middle column of the second magnetic core is inserted into the hollow area of ​​the second isolation column, the second arc-shaped protrusion abuts against the outer cylindrical surface of the second isolation column to prevent the second magnetic core and the second fixing component from separating from each other.

9. The fixing device according to claim 1, characterized in that When the first fixing member is fixedly connected to the second fixing member, the pair of the first arc-shaped frames and the pair of the second arc-shaped frames enclose an isolation space with a gap; When the two magnetic cores are connected to each other along their axial directions, the two pairs of arc-shaped bone walls enclose a receiving space, and both the first fixing component and the second fixing component are located in the receiving space; The first PCB winding and the second PCB winding are both located inside the isolation space, and at least parts of the first PCB winding and the second PCB winding can extend through the gap to the outside of the isolation space.

10. A planar transformer, characterized in that: include: Two magnetic cores with a central column, a first PCB winding, a second PCB winding, and a fixing device according to any one of claims 1 to 9; The first PCB winding is sleeved on the first fixing component of the fixing device, and the second PCB winding is sleeved on the second fixing component of the fixing device; The first magnetic core of the two magnetic cores is fixedly connected to the first fixing component, and the second magnetic core of the two magnetic cores is fixedly connected to the second fixing component. In this case, the first PCB winding and the second PCB winding can be isolated from the two magnetic cores by the fixing device. An air gap is provided between the two middle columns of the two magnetic cores, and the first PCB winding and the second PCB winding are both away from the air gap along the axial direction of the magnetic core.

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