Circuit board fixing structure and power converter

Abstract

The invention relates to the technical field of new energy, in particular to a circuit board fixing structure and a power converter. The circuit board fixing structure comprises a shell, a circuit board and a connecting assembly. The circuit board is positioned in the shell; the connecting assembly is used for fixing the circuit board to the shell, the connecting assembly comprises a first connecting piece and a second connecting piece, and the first connecting piece is fixedly connected with the shell; the second connecting piece is connected with the first connecting piece, the second connecting piece comprises a first limiting structure, the first limiting structure is clamped and matched with the circuit board, the first limiting structure comprises a clamping part and a limiting boss, the circuit board is limited between the clamping part and the limiting boss, and the clamping part and the limiting boss are used for limiting movement of the circuit board in the first direction; the first direction is the thickness direction of the circuit board, so that the assembly efficiency is improved, the fixing strength between the circuit board and the shell is enhanced, the circuit board can resist vibration and impact in the packaging drop test, transportation and use processes, and the risk of loosening or displacement is reduced.

Description

Technical Field

[0001] This disclosure relates to the field of new energy technology, and in particular to a circuit board fixing structure and a power converter. Background Technology

[0002] In related technologies, the methods of fixing circuit boards in power equipment (such as, but not limited to, inverters) mainly include fixing methods using screw connections (e.g., screws passing through through holes on the circuit board and locking to a metal chassis) and fixing methods using plastic support columns (e.g., plastic support columns passing through through holes on the circuit board and snapping into the circuit board).

[0003] Screw-based fastening methods are not conducive to improving assembly efficiency on the production line. Furthermore, to enhance the locking effect, metal bolts are typically used. Since conductive components on the circuit board have contact areas with ungrounded metal screws or the chassis, a large safety clearance must be reserved on the circuit board to comply with relevant electrical safety regulations. This limits hardware design and wiring paths, potentially leading to increased circuit board size, equipment volume, and cost.

[0004] While the use of plastic support columns for fixing helps save space for safety compliance, its fastening effect is limited, and it can usually only provide short-term support in the direction perpendicular to the board surface. Summary of the Invention

[0005] The purpose of this disclosure is to provide a circuit board fixing structure and a power converter to improve assembly efficiency, at least while enhancing the fixing strength of the circuit board.

[0006] To achieve the above objectives, this disclosure provides a circuit board fixing structure, including: case; Circuit board, the circuit board being located within the housing; and A connecting assembly is provided for fixing the circuit board to the housing. The connecting assembly includes a first connector and a second connector. The first connector is fixedly connected to the housing. The second connector is connected to the first connector and includes a first limiting structure. The first limiting structure engages with the circuit board. The first limiting structure includes a locking portion and a limiting boss. The circuit board is limited between the locking portion and the limiting boss. The locking portion and the limiting boss are used to restrict the movement of the circuit board in a first direction, wherein the first direction is the thickness direction of the circuit board.

[0007] In some embodiments of this disclosure, the snap-fit ​​portion is connected to the limiting boss.

[0008] In some embodiments of this disclosure, the number of connecting components is multiple, and the snap-fit ​​portion includes a stop portion that contacts the edge of the circuit board; Along the length of the circuit board, a portion of the plurality of connecting components are located on one side of the circuit board, and another portion of the connecting components are located on the other side of the circuit board; And / or, along the width direction of the circuit board, a portion of the plurality of connection components are located on one side of the circuit board, and another portion of the connection components are located on the other side of the circuit board.

[0009] In some embodiments of this disclosure, the second connector is provided with a first mounting hole; The housing is provided with a stud, which passes through the first mounting hole; the first connector includes a nut, which is connected to the stud to fix the second connector to the housing. Alternatively, the housing may be provided with a threaded hole, and the first connector may include a bolt, which passes through the first mounting hole and is connected to the threaded hole to fix the second connector to the housing.

[0010] In some embodiments of this disclosure, the second connector is provided with a second mounting hole, and the housing is provided with a guide post, which passes through the second mounting hole.

[0011] In some embodiments of this disclosure, the circuit board is provided with a first through hole; the latching part includes an elastic arm and a latch hook, one end of the elastic arm is connected to the limiting boss, and the other end of the elastic arm is connected to the latch hook; the elastic arm passes through the first through hole and abuts against the side of the circuit board away from the first connector.

[0012] In some embodiments of this disclosure, the number of elastic arms is two, and the two elastic arms are spaced apart; The number of first through holes is one, and both elastic arms pass through the first through hole. The wall of the first through hole can restrict the movement of the two elastic arms. Alternatively, there may be two first through holes, with each of the two first through holes corresponding to one of the two elastic arms, and the wall of the first through hole being able to restrict the movement of the corresponding elastic arm.

[0013] In some embodiments of this disclosure, the snap-fit ​​portion includes a protrusion; The circuit board is provided with a second through hole, and the protrusion is interference-fitted with the second through hole; or, the circuit board is provided with a blind hole, and the protrusion is interference-fitted with the blind hole.

[0014] In some embodiments of this disclosure, the cross-sectional shape of the protruding post is circular or polygonal.

[0015] In some embodiments of this disclosure, the second connector further includes a second limiting structure, which is detachably connected to the first connector.

[0016] In some embodiments of this disclosure, the second limiting structure includes a plurality of claws arranged at circumferential intervals to enclose and form a receiving cavity, and the first connector is provided with a protrusion, the claws being used to limit the protrusion within the receiving cavity.

[0017] In some embodiments of this disclosure, an adhesive is provided between the circuit board and the second connector.

[0018] In some embodiments of this disclosure, the second connector has a first recess on the surface facing the circuit board, and the adhesive at least partially fills the first recess; and / or, the circuit board has a second recess on the surface facing the second connector, and the adhesive at least partially fills the second recess.

[0019] In some embodiments of this disclosure, the first connector and the second connector are integrally formed, and the second connector is detachably connected to the circuit board.

[0020] In some embodiments of this disclosure, the second connector is made of an insulating material.

[0021] In some embodiments of this disclosure, the circuit board is provided with a third through hole, which extends along a predetermined direction within the surface of the circuit board. The latching portion includes a insert, which includes an insertion section and an extension section. Along the first direction, the insertion section is located on the side of the extension section closer to the first connector. Along the set direction, one end of the extension section protrudes from the insertion section. The insert passes through the third through hole. The portion of the extension section protruding from the insertion section can contact the side of the circuit board away from the first connector. The set direction is the length direction or the width direction of the circuit board.

[0022] In some embodiments of this disclosure, the first connector includes a support arm that extends along the first direction and is provided with a limiting hole. The second limiting structure of the second connector includes a spring sheet, the spring sheet is provided with a limiting protrusion, the spring sheet has a first working position and a second working position, at the first working position the limiting protrusion is limited to the limiting hole, at the second working position the limiting protrusion is separated from the limiting hole.

[0023] In some embodiments of this disclosure, a contact portion is provided at one end of the support arm near the circuit board; The contact portion contacts the side of the limiting boss that is away from the circuit board; Alternatively, a groove is provided on the side of the limiting boss away from the circuit board, and the contact portion is limited to the groove.

[0024] In some embodiments of this disclosure, the first connector further includes a connecting plate, which is fixedly connected to the end of the support arm away from the circuit board, and the connecting plate is fixedly connected to the housing.

[0025] In some embodiments of this disclosure, the circuit board is provided with a first operating hole, and the limiting boss is provided with a second operating hole, the second operating hole being able to communicate with the first operating hole.

[0026] In some embodiments of this disclosure, both the first connector and the second connector are made of conductive materials.

[0027] In some embodiments of this disclosure, the first connector is threaded to the housing; or, the first connector is press-fitted to the housing; or, the first connector is welded to the housing.

[0028] For the purposes described above, this disclosure also provides a power converter, including the circuit board fixing structure described in any of the above embodiments.

[0029] The main beneficial effects of this disclosure are: The circuit board fixing structure disclosed herein includes a first connector fixedly connected to the housing, a second connector connected to the first connector, and a first limiting structure in the second connector engaging with the circuit board. This not only facilitates assembly and improves assembly efficiency, but also enhances the fixing strength between the circuit board and the housing, enabling it to resist vibrations and impacts during packaging drop tests, transportation, and use, thereby reducing the risk of loosening or displacement. Attached Figure Description

[0030] To more clearly illustrate the technical solutions in the specific embodiments of this disclosure or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this disclosure. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0031] Figure 1 This is a schematic diagram of the circuit board fixing structure provided in an embodiment of the present disclosure; Figure 2 for Figure 1 A sectional view along line AA; Figure 3 for Figure 2 A magnified view of a section at point I; Figure 4 A schematic diagram of a first structure of the second connector in the circuit board fixing structure provided in this embodiment of the present disclosure; Figure 5 for Figure 1 A cross-sectional view along line BB; Figure 6 for Figure 5 Enlarged view of a section at point II; Figure 7 for Figure 5 Enlarged view of a section at point III; Figure 8 A schematic diagram of a second structure of the second connector in the circuit board fixing structure provided in this embodiment of the present disclosure; Figure 9 for Figure 8 A structural schematic diagram of the second connector from another perspective is shown; Figure 10 A schematic diagram of a first structure of the first connector in the circuit board fixing structure provided in this embodiment of the disclosure; Figure 11 A schematic diagram of a second structure of the first connector in the circuit board fixing structure provided in the embodiments of this disclosure; Figure 12 A schematic diagram of the circuit board fixing structure provided in an embodiment of this disclosure from another perspective; Figure 13 for Figure 12 A cross-sectional view along line DD; Figure 14 for Figure 13 Enlarged view of a section at point IV; Figure 15 A schematic diagram of a third structure of the second connector in the circuit board fixing structure provided in the embodiments of this disclosure; Figure 16 for Figure 13 A magnified view of section V; Figure 17 A schematic diagram of a fourth structure of the second connector in the circuit board fixing structure provided in the embodiments of this disclosure; Figure 18 A schematic diagram of a fifth structure of the second connector in the circuit board fixing structure provided in this embodiment of the present disclosure; Figure 19 for Figure 1 A cross-sectional view along the CC line; Figure 20 for Figure 19A magnified view of a section at point VI; Figure 21 A schematic diagram of a sixth structure in which the second connector and the first connector cooperate in the circuit board fixing structure provided in this embodiment of the disclosure (the limiting protrusion is limited to the limiting hole). Figure 22 A schematic diagram of a sixth structure in which the second connector and the first connector cooperate in the circuit board fixing structure provided in this embodiment of the present disclosure (the limiting protrusion disengages from the limiting hole). Figure 23 This is a partial structural diagram of the circuit board in the circuit board fixing structure provided in the embodiments of this disclosure; Figure 24 for Figure 23 A magnified view of section VII.

[0032] The annotations in the attached figures are explained as follows: 10. Housing; 11. Stud; 12. Guide post; 20. Circuit board; 21. First through hole; 211. First hole wall; 212. Second hole wall; 23. Blind hole; 24. Third through hole; 25. First operating hole; 30. Connecting assembly; 31. First connector; 311. Protrusion; 312. Support arm; 3121. Limiting hole; 313. Contact part; 314. Connecting plate; 3141. Placement hole; 32. Second connector; 321A. Stop; 3211A. Stop Surface; 3212A, limiting hook; 3211B, elastic arm; 3212B, hook; 321C, protruding post; 321D, insert; 3211D, insertion section; 3212D, extension section; 322, limiting boss; 3221, first recess; 3222, second operating hole; 323, base; 3231, first mounting hole; 3232, second mounting hole; 324, claw; 325, spring; 3251, limiting protrusion; 3252, guide flange; 40, adhesive. Detailed Implementation

[0033] The technical solutions of this disclosure will be clearly and completely described below with reference to the embodiments. Obviously, the described embodiments are only some embodiments of this disclosure, not all embodiments. Based on the embodiments of this disclosure, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this disclosure.

[0034] In the description of this disclosure, it should be noted that the terms "center," "upper," "lower," "left," "right," "vertical," "horizontal," "inner," and "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings, and are only for the convenience of describing this disclosure and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation, and therefore should not be construed as a limitation of this disclosure. Furthermore, the terms "first," "second," and "third" are used for descriptive purposes only and should not be construed as indicating or implying relative importance.

[0035] In the description of this disclosure, it should be noted that, unless otherwise expressly specified and limited, the terms "installation," "connection," and "joining" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; and they can refer to the internal connection between two components. Those skilled in the art can understand the specific meaning of the above terms in this disclosure based on the specific circumstances.

[0036] See Figures 1 to 24 As shown, this embodiment provides a circuit board fixing structure, including a housing 10, a circuit board 20, and a connecting assembly 30; the circuit board 20 is located inside the housing 10; the connecting assembly 30 is used to fix the circuit board 20 to the housing 10, and the connecting assembly 30 includes a first connecting member 31 and a second connecting member 32. The first connecting member 31 is fixedly connected to the housing 10; the second connecting member 32 is connected to the first connecting member 31, and the second connecting member 32 includes a first limiting structure. The first limiting structure engages with the circuit board 20. The first limiting structure includes a snap-fit ​​portion and a limiting boss 322. The circuit board 20 is limited between the snap-fit ​​portion and the limiting boss 322. The snap-fit ​​portion and the limiting boss 322 are used to restrict the movement of the circuit board 20 in a first direction.

[0037] The circuit board fixing structure provided in this embodiment has a first connector 31 fixedly connected to the housing 10, and a second connector 32 connected to the first connector 31. The first limiting structure in the second connector 32 engages with the circuit board 20, which not only facilitates assembly and improves assembly efficiency, but also enhances the fixing strength between the circuit board and the housing, enabling it to resist vibration and impact during packaging drop tests, transportation, and use, and reducing the risk of loosening or displacement.

[0038] Specifically, a clamping space is formed by the snap-fit ​​part and the limiting boss 322 to ensure that the circuit board 20 can be accurately positioned in its designed location. During testing, transportation, and equipment operation, the risk of the circuit board loosening in the first direction due to factors such as vibration and impact is reduced, thereby maintaining stability and reliability.

[0039] For example, the circuit board fixing structure can restrict the movement of the circuit board 20 in at least two of the following directions: a first direction (represented by arrow direction D1), a second direction (represented by arrow direction D2), and a third direction (represented by arrow direction D3), wherein the second direction and the third direction are both perpendicular to the first direction.

[0040] It should be understood that the first direction can be the thickness direction of the circuit board 20, and the first direction is perpendicular to the surface of the circuit board 20. One of the second direction and the third direction can be the length direction of the circuit board 20, and the other can be the width direction of the circuit board 20, but is not limited thereto.

[0041] The circuit board 20 can be, but is not limited to, a power board. The housing 10 is made of metal and can serve as the enclosure of a device (e.g., but not limited to an inverter) or as part of the device's enclosure.

[0042] There are various forms of connecting components 30. Some connecting components 30 can fix the circuit board 20 inside the board, while others can fix the circuit board 20 at the edge of the board. Among them, fixing inside the board refers to the fixing method of making holes (through holes or blind holes) on the surface of the circuit board 20 or mating with the surface of the circuit board 20; fixing at the edge of the board refers to the fixing method of fixing on the outer contour of the circuit board 20, and usually no holes are made on the circuit board 20.

[0043] The number of connecting components 30 can be one or more. When there are multiple connecting components 30, the structures of each connecting component 30 can be the same or not completely identical. For example, when fixing the circuit board 20 inside the board, one connecting component 30 can be used to limit and fix the circuit board 20 in at least two of the first, second, and third directions. In scenarios where multiple connecting components 30 are required to limit and fix the circuit board 20 (for example, when the circuit board is large, it is usually necessary to add a connecting component 30 at a certain distance, or when there are heavy electrical components on the circuit board, at least one connecting component 30 needs to be added near the heavy electrical components), appropriate connecting components 30 can be selected according to actual needs. This helps to reduce the path restrictions on the wiring and placement of electrical components on the board, saves circuit board layout space, and effectively reduces the size of the circuit board; while keeping the size of the circuit board unchanged, more electrical components can be placed.

[0044] For example, when fixing the edge of the circuit board 20, at least four connecting components 30 can be used. Taking four connecting components 30 as an example, the four connecting components 30 can be the same. Two of the connecting components 30 can be set on both sides of the length direction of the circuit board 20, and the other two connecting components 30 can be set on both sides of the width direction of the circuit board 20.

[0045] Of course, multiple connecting components 30 can also be used to fix the circuit board 20 both inside the board and at the edge of the board.

[0046] Typically, circuit board 20 has numerous lines and conductive components (such as various electrical components and metal fasteners) installed on it. To ensure the safety and reliability of the equipment, the arrangement and routing of electrical components on circuit board 20 must comply with safety regulations, namely, meeting electrical safety clearance and creepage distance requirements. Electrical safety clearance refers to the shortest straight-line distance in air between two conductive components or between a conductive component and the equipment casing; creepage distance refers to the shortest path between two conductive components measured along the surface of an insulator.

[0047] In some embodiments, the second connector 32 is made of an insulating material. In this case, the area on the circuit board 20 that contacts the second connector 32 does not need to consider safety regulations. The electrical safety clearance and creepage distance between the conductive parts on the circuit board 20 and the housing 10 are sufficiently far to meet safety requirements. This reduces the clearance space reserved on the circuit board, which is beneficial for reducing the size of the circuit board and optimizing the layout of electrical components and wiring.

[0048] For example, compared to the safety clearance and locking area required for a single M4 metal screw in existing solutions, the total area occupied by the second connector 32 in a single connection assembly 30 on the circuit board 20 in this embodiment can be reduced by at least 300 mm². 2 .

[0049] For example, the insulating material can be, but is not limited to, plastic; any material that can achieve the insulating function falls within the protection scope of this disclosure.

[0050] In some embodiments, the snap-fit ​​portion is connected to the limiting boss 322.

[0051] There are various forms of the snap-fit ​​part and the limiting boss 322, which will be described in detail below.

[0052] In some embodiments, see Figure 3As shown, the snap-fit ​​portion includes a stop portion 321A, which contacts the edge of the circuit board 20; as previously described, this type of snap-fit ​​portion is used to fix the edge of the circuit board 20. When only edge fixing is used, the number of connecting components 30 is multiple, usually not less than four, but not limited to this. Taking four as an example, along the length direction of the circuit board, two of them are as follows: Figure 3 One of the connecting components shown is located on one side of the circuit board 20, and the other connecting component is located on the other side of the circuit board 20; along the width direction of the circuit board, one of the other two connecting components is located on one side of the circuit board 20, and the other connecting component is located on the other side of the circuit board 20.

[0053] Of course, when using both edge fixing and internal fixing methods, at least two methods can be used. Figure 3 The connecting component 30 shown limits the circuit board 20 along its length or along its width.

[0054] Specifically, see Figure 4 As shown, the stop portion 321A has a stop surface 3211A, which can contact one side of the circuit board 20. The stop portion 321A is provided with a limiting hook portion 3212A. The stop portion 321A can undergo elastic deformation. When the circuit board 20 is installed, the circuit board 20 contacts the limiting hook portion 3212A and presses the stop portion 321A away from the limiting boss 322, causing the stop portion 321A to open away from the limiting boss 322. After the circuit board 20 is installed in place, the stop portion 321A returns to its original shape, and the circuit board 20 is limited and fixed between the limiting hook portion 3212A and the limiting boss 322.

[0055] In some embodiments, see Figure 3 and Figure 4 As shown, the second connector 32 is provided with a first mounting hole 3231; the housing 10 is provided with a stud 11, which passes through the first mounting hole 3231; the first connector 31 includes a nut, which is connected to the stud 11 to fix the second connector 32 to the housing 10. At this time, the first connector 31 can abut against the second connector 32.

[0056] See also Figure 4 As shown, the second connector 32 also includes a base 323, and a first mounting hole 3231 is disposed on the base 323. The stop portion 321A and the limiting boss 322 are both connected to the base 323. For example, the stop portion 321A, the limiting boss 322 and the base 323 can be integrally formed by injection molding.

[0057] In some embodiments, the stud 11 and the housing 10 can be riveted or welded, but are not limited thereto. Any method that can achieve a fixed connection between the stud 11 and the housing 10 falls within the protection scope of this disclosure.

[0058] In other embodiments, the housing 10 is provided with a threaded hole, and the first connector 31 includes a bolt, which passes through the first mounting hole 3231 and is connected to the threaded hole. The head of the bolt can fix the second connector 32 to the housing 10.

[0059] In some embodiments, see continue to see Figure 4 As shown, the second connector 32 is provided with a second mounting hole 3232, and the housing 10 is provided with a guide post 12, which passes through the second mounting hole 3232. By providing the guide post 12, the second connector 32 can be prevented from rotating during the tightening of the nut, ensuring that the stop surfaces 3211A of the two stop portions 321A along the length or width direction of the circuit board are parallel, thereby ensuring that the circuit board 20 can be smoothly installed in place.

[0060] For example, a second mounting hole 3232 is provided on the base 323, and the second mounting hole 3232 is located on the side of the limiting boss 322 away from the stop portion 321A.

[0061] In some embodiments, the guide post 12 and the housing 10 can be riveted or welded, but are not limited thereto. Any method that can achieve a fixed connection between the guide post 12 and the housing 10 falls within the protection scope of this disclosure.

[0062] In one embodiment, see Figure 23 and Figure 24 As shown, the circuit board 20 has a first through hole 21; see also Figure 7 and Figure 8 As shown, the snap-fit ​​part includes an elastic arm 3211B and a snap hook 3212B. One end of the elastic arm 3211B is connected to the limiting boss 322, and the other end of the elastic arm 3211B is connected to the snap hook 3212B. The elastic arm 3211B can undergo elastic deformation to pass through the first through hole 21, and the snap hook 3212B abuts against the side of the circuit board 20 away from the first connector 31.

[0063] Along the first direction, the elastic arm 3211B is located on the side of the limiting boss 322 away from the first connector 31, and the elastic arm 3211B, the hook 3212B and the limiting boss 322 can be integrally formed.

[0064] The wall of the first through hole 21 can be basically fitted with the elastic arm 3211B, or a small gap can be left to facilitate assembly. It should be noted that the size of the gap is not limited, as long as it can facilitate assembly and restrict the movement of the circuit board.

[0065] During assembly, the first connector 31, the second connector 32, and the housing 10 can be assembled together first. Then, the circuit board 20 is pressed, and the wall of the first through hole 21 contacts the hook 3212B and squeezes the elastic arm 3211B through the hook 3212B, causing the elastic arm 3211B to undergo elastic deformation, thereby allowing the hook 3212B to pass through the first through hole 21. When the hook 3212B disengages from the wall of the first through hole 21, the elastic arm 3211B returns to its original state. At this time, the circuit board 20 is limited between the hook 3212B and the limiting boss 322.

[0066] For example, there are two elastic arms 3211B, which are spaced apart and arranged opposite to each other, and are capable of elastic deformation in the direction of moving closer to each other.

[0067] In some embodiments, there are two first through holes 21, which are spaced apart on the surface of the circuit board 20. For example, the two first through holes 21 may be spaced apart along a second direction, but this is not a limitation. Two elastic arms 3211B are connected to the two first through holes 21 in a one-to-one correspondence. The surface of one elastic arm 3211B away from the other elastic arm 3211B contacts the hole wall of the corresponding first through hole 21 near that surface. The hole wall of the first through hole 21 can restrict the movement of the corresponding elastic arm 3211B.

[0068] Both first through holes 21 can be rectangular holes, for example, see [link to example]. Figure 23 and Figure 24 As shown, the walls of the two rectangular holes that are far apart are designated as the first hole wall 211, and the walls of the two rectangular holes that are close together are designated as the second hole wall 212. When the two elastic arms 3211B are inserted into their respective rectangular holes, the first hole wall 211 can contact the hook 3212B. By squeezing the hook, the two elastic arms undergo elastic deformation in the direction that they are close to each other, and pass through the corresponding first through hole 21 respectively. When the hook 3212B is completely out of the first through hole 21, the elastic arm 3211B can return to its original shape. At this time, the hook and the limiting boss limit the circuit board; or it basically returns to its original shape, that is, it maintains a certain deformation to keep the elastic arm 3211B in contact with the first hole wall 211. In the latched state, the hook 3212B, the circuit board 20 and the limiting boss 322 are interlocked. The hook 3212B and the circuit board 20 can be in contact or have a small gap. For example, the first hole wall 211 of each first through hole 21 can contact the elastic arm 3211B inside it to limit the circuit board 20 in the second direction. Of course, there can also be a small gap between the first hole wall 211 of each first through hole 21 and the elastic arm 3211B inside it, so as to facilitate assembly while satisfying the limitation of the circuit board.

[0069] In some embodiments, the second connector 32 further includes a second limiting structure, which is detachably connected to the first connector 31. This facilitates the removal of the circuit board 20 from the housing 10 for inspection or replacement.

[0070] In one specific implementation, see Figure 9 As shown, the second limiting structure includes multiple claws 324, which are arranged circumferentially to form a receiving cavity. The first connecting member 31 is provided with a protrusion 311, and the claws 324 are used to limit the protrusion 311 within the receiving cavity. Exemplarily, in the first direction, the claws 324 abut against the protrusion 311.

[0071] When the second connector 32 is assembled with the first connector 31, the protrusion 311 allows the claw 324 to elastically deform and extend into the receiving cavity, achieving quick and convenient snap-fit ​​assembly and further improving assembly efficiency. Simultaneously, it effectively restricts the movement of the protrusion 311 along the first direction, which, in conjunction with the hook 3212B and the limiting boss 322 restricting the circuit board 20 along the first direction, securely fixes the circuit board 20 to the housing 10.

[0072] In addition, multiple claws 324 form a surrounding enclosure around the protrusion 311, enhancing its resistance to vibration and impact and reducing the risk of the circuit board becoming loose during packaging drop tests, transportation, and use.

[0073] It should be noted that the second limiting structure is not limited to the above-mentioned form. Any structural form that can achieve a detachable connection with the first connecting member 31 falls within the protection scope of this disclosure.

[0074] In some embodiments, the first connector 31 is press-fitted to the housing 10. For example, when the housing 10 is integrally formed from sheet metal via sheet metal processing or deep drawing, such as... Figure 10 The first connector 31 shown can be press-fitted to the housing 10. The housing 10 is provided with a press-fit opening, the diameter of which can be slightly larger than the diameter of the protrusion 311. The protrusion 311 enters the press-fit opening from the side of the housing 10 away from the circuit board 20, thereby realizing the press-fitting connection between the first connector 31 and the housing 10.

[0075] In other embodiments, the first connector 31 is threadedly connected to the housing 10. For example, when the housing 10 is manufactured using a die-casting process, a connecting boss can be integrally formed, and an internal thread can be machined within the connecting boss to form a threaded hole of a certain depth. Figure 11The first connector 31 shown is provided with an external thread, and the surface of the external thread is provided with anti-loosening adhesive or anti-drop adhesive to prevent the first connector 31 from rotating. The threaded section of the first connector 31 is screwed into the threaded hole of the housing 10 to achieve a fixed connection between the first connector 31 and the housing 10.

[0076] In other embodiments, the first connector 31 may also be welded to the housing 10.

[0077] During assembly, the first connector 31 can be connected to the housing 10 first, and then the second limiting structure of the second connector 32 on which the circuit board 20 is mounted can be connected to the first connector 31.

[0078] In some embodiments, see Figure 7 As shown, an adhesive 40 is provided between the circuit board 20 and the second connector 32, which can further improve the fixing firmness of the circuit board 20 and reduce the risk of the circuit board 20 separating from the first connector 31 during packaging drop tests, transportation and use.

[0079] For example, adhesive 40 may be a structural adhesive, including but not limited to epoxy resin adhesive.

[0080] In some embodiments, see Figure 8 As shown, the second connector 32 has a first recess 3221 on its surface facing the circuit board 20. The adhesive 40 at least partially fills the first recess 3221, which enhances the bonding interface's ability to resist external loads and ensures the stability and reliability of the fixed connection between the second connector 32 and the circuit board 20. For example, the first recess 3221 is located on the limiting boss 322. The first recess 3221 can be a groove, and there can be multiple grooves to increase the bonding area of ​​the adhesive 40 and improve the bonding strength.

[0081] In other embodiments, the surface of the circuit board 20 facing the second connector 32 is provided with a second recess (not shown in the figure), and the adhesive 40 at least partially fills the second recess.

[0082] For example, a certain area of ​​copper foil is pre-laid in the area where the circuit board 20 mates with the limiting boss 322. By etching (e.g., plasma etching), mechanical polishing, or roughening processes (e.g., micro-roughening), a rough texture (e.g., stripes, grids, or irregular micro-pits) is formed on the surface of the copper foil, which can further improve the bonding strength.

[0083] In other embodiments, a first recess 3221 may be provided on the surface of the second connector 32 facing the circuit board 20, and a second recess may be provided on the surface of the circuit board 20 facing the second connector 32, thereby further enhancing the bonding strength.

[0084] In some embodiments, see Figure 14 and Figure 15 As shown, the number of first through holes 21 can also be one, and both elastic arms 3211B are inserted through the first through hole 21. The hole wall of the first through hole 21 can restrict the movement of the two elastic arms 3211B.

[0085] For example, the first through hole 21 can be a circular hole. The two elastic arms 3211B elastically deform in a direction that brings them closer together to pass through the first through hole 21. When the two hooks have completely passed through the first through hole, the two elastic arms 3211B can return to their original shape. At this time, the hooks and the limiting boss can limit the circuit board; or the two elastic arms 3211B basically return to their original shape, that is, maintain a certain deformation to maintain the abutment state between the elastic arms 3211B and the hole wall of the first through hole. The mutually distancing surfaces of the two elastic arms 3211B can be arc-shaped surfaces to facilitate contact with the hole wall of the circular hole.

[0086] In some embodiments, see Figure 16 As shown, the snap-fit ​​portion includes a protrusion 321C; the circuit board 20 is provided with a second through hole, and the protrusion 321C can undergo elastic deformation and be interference-fitted with the second through hole (not shown in the figure); or, the circuit board 20 is provided with a blind hole 23, and the protrusion 321C can undergo elastic deformation and be interference-fitted with the blind hole 23. See also Figure 16 As shown, the protrusion 321C is disposed on the side of the limiting protrusion 322 near the circuit board 20, and the protrusion 321C and the limiting protrusion 322 are integrally formed.

[0087] By interfering with the second through hole or blind hole 23 through the protrusion 321C, the upward movement of the circuit board 20 in the first, second, and third directions can be restricted to a certain extent. The number of protrusions 321C can be multiple; see [reference needed]. Figure 17 As shown, there are two protrusions 321C. This method can further restrict the movement of the circuit board 20 in the second and third directions, while preventing the circuit board 20 from rotating.

[0088] See Figure 18 As shown, the number of protrusions 321C can be one. The cross-sectional shape of the protrusion 321C can be polygonal or elliptical. The cross-sectional shape is not circular, which can prevent the circuit board 20 from rotating.

[0089] Of course, the protrusion 321C may also include a first sub-pillar, a second sub-pillar and a third sub-pillar. The diameters of the first sub-pillar and the third sub-pillar are both larger than that of the second sub-pillar. The second sub-pillar is located between the first sub-pillar and the third sub-pillar. The axial dimension of the second sub-pillar is adapted to the thickness of the circuit board 20. The first sub-pillar undergoes elastic deformation and passes through the second through hole. The circuit board 20 is limited to the surfaces of the first sub-pillar and the third sub-pillar that are close to each other.

[0090] When the circuit board 20 is provided with a blind hole 23, the blind hole 23 does not occupy the area of ​​the front side of the circuit board 20 (i.e. the surface away from the first connector 31), ensuring that the front side of the circuit board 20 can still be used for wiring and placement of conductive components.

[0091] In some embodiments, the first connector 31 and the second connector 32 are integrally formed, and the second connector 32 is detachably connected to the circuit board 20. For example, the first connector 31 and the second connector 32 can be integrally formed by injection molding. Detachably connecting the circuit board 20 to the second connector 32 facilitates the inspection or replacement of the circuit board 20. In this case, reference can be made to... Figure 14 and Figure 15 The second connector 32 does not require a second limiting structure. Instead, the first connector 31 and the second connector 32 are integrally formed, which further simplifies the assembly steps and improves the assembly efficiency.

[0092] Meanwhile, since the second connector 32 is detachably connected to the circuit board 20, it does not need to be bonded with adhesive 40. Therefore, it is not necessary to provide a first recess 3221 on the limiting boss 322, nor is it necessary to provide a second recess on the circuit board 20, which simplifies the manufacturing process of the second connector 32 and the circuit board 20.

[0093] In one specific embodiment, the first connector 31 is made of a conductive material, such as metal; the second connector 32 is made of an insulating material, such as plastic. Depending on the molding process of the housing 10, the first connector 31 can be riveted to the housing 10, threaded to the housing 10, or welded to the housing 10.

[0094] In another specific embodiment, both the first connector 31 and the second connector 32 are made of insulating materials, such as plastic. Typically, the plastic first connector 31 is threaded to the housing 10.

[0095] Typically, a grounding screw needs to be installed on the circuit board of electrical equipment so that a certain line on the circuit board is connected to the chassis through the grounding screw, and then to the ground of the installation site.

[0096] In some embodiments, both the first connector 31 and the second connector 32 are made of conductive materials. This allows grounding to be achieved without screws.

[0097] Compared to the indirect grounding via the screw and chassis after grounding screw fixation, the snap-fit ​​method of this embodiment can complete the grounding of the circuit board 20 and the housing 10 at the moment of assembly, eliminating the extra step of screw tightening. At the same time, since the snap-fit ​​part itself is a grounded metal part, there is no need to consider the safety avoidance requirements between it and other conductive parts on the circuit board 20.

[0098] In one specific implementation, see Figures 19 to 24 As shown, the circuit board 20 is provided with a third through hole 24. The third through hole 24 extends in a set direction within the surface of the circuit board 20. The set direction is either the length direction or the width direction of the circuit board 20. For example, the set direction can be a second direction, but it is not limited to this. The snap-fit ​​part includes a tab 321D. The tab 321D includes an insertion section 3211D and an extension section 3212D. In a first direction, the insertion section 3211D is located on the side of the extension section 3212D near the first connector 31. In a set direction, one end of the extension section 3212D protrudes from the insertion section 3211D. The tab 321D passes through the third through hole 24. The part of the extension section 3212D that protrudes from the insertion section 3211D can contact the side of the circuit board 20 away from the first connector 31.

[0099] A solder pad is reserved in the area where the circuit board 20 contacts the limiting boss 322. The insert 321D passes directly through the third through hole 24 of the circuit board 20 and moves in a set direction, so that the hole wall of the third through hole 24 contacts the side wall of the insertion section 3211D. At the same time, the part of the extension section 3212D protruding from the insertion section 3211D overlaps the circuit board 20. Then the limiting boss 322 is soldered to the circuit board 20, thereby restricting the movement of the circuit board 20 in the first direction, the second direction and the third direction, and preventing the circuit board 20 from loosening during vibration, impact, testing or use.

[0100] In some embodiments, the first connector 31 includes a support arm 312 extending along a first direction, and the support arm 312 is provided with a limiting hole 3121; the second limiting structure of the second connector 32 includes a spring piece 325, the spring piece 325 is provided with a limiting protrusion 3251, the spring piece 325 has a first station and a second station, in the first station, the limiting protrusion 3251 is limited in the limiting hole 3121, and in the second station, the limiting protrusion 3251 is separated from the limiting hole 3121.

[0101] See Figure 20As shown, there are two support arms 312 and two spring pieces 325. The two spring pieces 325 are connected by a limiting boss 322. In this embodiment, the limiting boss 322 can be a sheet-like structure. The spring piece 325 and the limiting boss 322 are integrally formed. The free end of the spring piece 325 is provided with a guide flange 3252, and the two guide flanges 3252 form a flared opening. Before assembly, the two spring pieces 325 are roughly parallel, and the distance between the two surfaces of the two spring pieces 325 that are close to each other is basically equal to the distance between the two surfaces of the two support arms 312 that are far apart from each other. During assembly, under the guidance of the guide flange 3252, the two support arms 312 can smoothly enter between the two spring pieces 325. After the limiting protrusion 3251 contacts the support arm 312, it can open the spring piece 325. When the limiting protrusion 3251 is aligned with the limiting hole 3121, the spring piece 325 can return to its original shape, so that the limiting protrusion 3251 limits the limiting hole 3121.

[0102] For ease of installation, the limiting hole 3121 can be designed as an irregular shape instead of a round hole.

[0103] In some embodiments, see Figure 20 As shown, the support arm 312 has a contact portion 313 at one end near the circuit board 20. The contact portion 313 can contact the second connector 32 to achieve a reliable grounding function. For example, the contact portion 313 includes two protrusions, which are spaced apart. This not only achieves contact conductivity but also reduces the weight of the first connector 31, thereby reducing the weight of the overall structure.

[0104] In some embodiments, the contact portion 313 contacts the side of the limiting boss 322 away from the circuit board 20. For example, both protrusions are bent at approximately 90° relative to the support arm 312, thereby increasing the contact area between the protrusions and the side of the limiting boss 322 away from the circuit board 20 and improving conductivity.

[0105] In other embodiments, a groove (not shown) is provided on the side of the limiting boss 322 away from the circuit board 20, and the contact portion 313 is confined within the groove. In this case, the extending direction of the boss can be consistent with the extending direction of the support arm 312, without the need for bending.

[0106] In some embodiments, the first connector 31 further includes a connecting plate 314, which is fixedly connected to the end of the support arm 312 away from the circuit board 20, and is fixedly connected to the housing 10.

[0107] For example, the connecting plate 314 can be a flat plate to facilitate better fit and connection with the housing 10. The connecting plate 314 is integrally formed with two support arms 312, both of which are located on the same side of the connecting plate 314.

[0108] In some embodiments, the connecting plate 314 is welded to the housing 10, and the connecting plate 314 is provided with a placement hole 3141 for placing solder. Solder is placed in the placement hole 3141 for welding, and the solder flows between the connecting plate 314 and the housing 10, increasing the welding contact area and improving the welding strength.

[0109] In other embodiments, the connecting plate 314 and the housing 10 may also be connected by fasteners such as bolts, nuts or rivets.

[0110] In some embodiments, the circuit board 20 is provided with a first operating hole 25, and the limiting boss 322 is provided with a second operating hole 3222, the second operating hole 3222 being able to communicate with the first operating hole 25. For example, the first operating hole 25 and the second operating hole 3222 can both be circular holes, or they can be through holes of other shapes, and the shapes of the first operating hole 25 and the second operating hole 3222 can be the same or different.

[0111] See Figure 22 As shown, the grounding connection here can be removed using an unlocking tool (e.g., an unlocking rod) (not shown in the figure). For example, the unlocking rod is passed from above the circuit board 20 downwards through the first operating hole 25 and the second operating hole 3222 until it contacts the limiting protrusion 3251 and opens the two spring tabs 325. At this time, the limiting protrusion 3251 disengages from the limiting hole 3121, and the circuit board 20 can be removed and moved away along the first direction.

[0112] It should be understood that when the second operating hole 3222 is connected to the first operating hole 25, the edge of the second operating hole 3222 and the edge of the first operating hole 25 can coincide or be offset, which can ensure that the unlocking tool can pass through the first operating hole 25 and the second operating hole 3222 and open the two spring pieces 325, so that the limiting protrusion 3251 disengages from the limiting hole 3121 and falls within the protection scope of this disclosure.

[0113] In summary, the circuit board fixing structure provided in this embodiment not only improves assembly efficiency, but also restricts the movement of the circuit board 20 in at least two of the first, second, and third directions, thereby enhancing the fixing strength of the circuit board 20 and enabling it to resist vibration and impact during packaging drop tests, transportation, and use, reducing the risk of loosening or displacement.

[0114] Furthermore, when the second connector 32 is made of insulating material, safety requirements can be met without reserving a large safety clearance space, which helps to reduce the size of the circuit board 20 and optimize the layout of electrical components and wiring. When both the second connector 32 and the first connector 31 are made of conductive material, grounding function can be achieved without considering safety clearance.

[0115] The power converter provided in this disclosure includes the circuit board fixing structure provided in any of the above embodiments. Because the power converter provided in this disclosure uses the circuit board fixing structure provided in any of the above embodiments, it not only facilitates assembly and improves assembly efficiency, but also enhances the fixing strength between the circuit board 20 and the housing, enabling it to resist vibration and impact during packaging drop tests, transportation, and use, reducing the risk of loosening or displacement.

[0116] In some embodiments, the power converter can be an inverter, the inverter includes a chassis, the housing 10 may include the chassis base plate, and the first connector 31 is fixedly connected to the chassis base plate.

[0117] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of this disclosure, and are not intended to limit them. Although this disclosure has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features therein. Such modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of this disclosure.

Claims

1. A circuit board fixing structure characterized by comprising: The application relates to a connecting assembly for fixing a circuit board to a shell, comprising: the shell; the circuit board located in the shell; and the connecting assembly. The connecting assembly comprises a first connecting piece and a second connecting piece, the first connecting piece is fixedly connected with the shell, the second connecting piece is connected with the first connecting piece, the second connecting piece comprises a first limiting structure, the first limiting structure is clamped with the circuit board, the first limiting structure comprises a clamping part and a limiting boss, the circuit board is limited between the clamping part and the limiting boss, the clamping part and the limiting boss are used for limiting the movement of the circuit board in a first direction, wherein the first direction is the thickness direction of the circuit board. The clamping part is connected with the limiting boss. The number of the connecting assemblies is plural, the clamping part comprises a stop part, the stop part is in contact with the edge of the circuit board. Along the length direction of the circuit board, part of the connecting assemblies is located on one side of the circuit board, and the other part of the connecting assemblies is located on the other side of the circuit board.

2. The circuit board fixing structure according to claim 1, characterized by And / or, along the width direction of the circuit board, part of the connecting assemblies is located on one side of the circuit board, and the other part of the connecting assemblies is located on the other side of the circuit board.

3. The circuit board fixing structure according to claim 2, characterized by The second connecting piece is provided with a first mounting hole. The shell is provided with a stud, the stud is arranged in the first mounting hole, the first connecting piece comprises a nut, the nut is connected with the stud, and the second connecting piece is fixedly mounted on the shell. Or, the shell is provided with a threaded hole, the first connecting piece comprises a bolt, the bolt is arranged in the first mounting hole and connected with the threaded hole, and the second connecting piece is fixedly mounted on the shell.

4. The circuit board fixing structure according to claim 2, characterized by The second connecting piece is provided with a second mounting hole, and the shell is provided with a guide column arranged in the second mounting hole. The circuit board is provided with a first through hole, the clamping part comprises an elastic arm and a clamping hook, one end of the elastic arm is connected with the limiting boss, the other end of the elastic arm is connected with the clamping hook, the elastic arm is arranged in the first through hole, and the clamping hook is in abutment with one side of the circuit board away from the first connecting piece. The number of the elastic arms is two, and the two elastic arms are arranged at intervals.

5. The circuit board fixing structure according to claim 4, characterized by The number of the first through holes is one, and the two elastic arms are arranged in the first through hole, and the hole wall of the first through hole can limit the movement of the two elastic arms.

6. The circuit board fixing structure according to claim 2, characterized by Or, the number of the first through holes is two, the two first through holes are connected with the two elastic arms one by one, and the hole wall of the first through hole can limit the movement of the corresponding elastic arm.

7. The circuit board fixing structure according to claim 6, characterized by The clamping part comprises a convex column. The circuit board is provided with a second through hole, the convex column is in interference fit with the second through hole, or the circuit board is provided with a blind hole, and the convex column is in interference fit with the blind hole. The shape of the cross section of the convex column is circular or polygonal.

8. The circuit board fixing structure according to claim 2, characterized by The second connecting piece further comprises a second limiting structure, and the second limiting structure is detachably connected with the first connecting piece. ​ 9. The circuit board fixing structure according to claim 8, characterized by ​ 10. The circuit board fixing structure according to any one of claims 1 to 9, characterized in that, ​ 11. The circuit board fixing structure according to claim 10, characterized by The second limiting structure comprises a plurality of clamping claws which are arranged in a circumferential direction and are spaced apart to enclose a receiving cavity, and the first connecting piece is provided with a protruding portion, and the clamping claws are used to limit the protruding portion in the receiving cavity.

12. The circuit board fixing structure according to any one of claims 10, characterized by, An adhesive is arranged between the circuit board and the second connecting piece.

13. The circuit board fixing structure according to claim 12, characterized by The surface of the second connecting piece towards the circuit board is provided with a first recess, and the adhesive is at least partially filled in the first recess; and / or, the surface of the circuit board towards the second connecting piece is provided with a second recess, and the adhesive is at least partially filled in the second recess.

14. The circuit board fixing structure according to any one of claims 1 to 9, characterized in that, The first connecting piece and the second connecting piece are integrally formed, and the second connecting piece is detachably connected with the circuit board.

15. The circuit board fixing structure according to any one of claims 1 to 9, characterized by The material of the second connecting piece is an insulating material.

16. The circuit board fixing structure according to claim 2, characterized by The circuit board is provided with a third through hole which extends in a set direction in the surface of the circuit board. The clamping portion comprises an insertion piece which comprises an insertion segment and an extension segment, along the first direction, the insertion segment is located on the side of the extension segment close to the first connecting piece, along the set direction, one end of the extension segment protrudes from the insertion segment, the insertion piece is arranged in the third through hole, and the part of the extension segment protruding from the insertion segment can contact the side of the circuit board away from the first connecting piece, wherein the set direction is the length direction or the width direction of the circuit board.

17. The circuit board fixing structure according to claim 16, characterized by The first connecting piece comprises a support arm which extends along the first direction, and the support arm is provided with a limiting hole. The second limiting structure of the second connecting piece comprises a spring piece which is provided with a limiting protrusion, and the spring piece has a first station and a second station, in the first station, the limiting protrusion is limited in the limiting hole, and in the second station, the limiting protrusion is separated from the limiting hole.

18. The circuit board fixing structure according to claim 17, characterized by The end of the support arm close to the circuit board is provided with a contact portion; The contact portion contacts the side of the limiting protrusion away from the circuit board; Or, the side of the limiting protrusion away from the circuit board is provided with a groove, and the contact portion is limited in the groove.

19. The circuit board fixing structure according to Claim 17, wherein The first connecting piece further comprises a connecting plate which is fixedly connected with the end of the support arm away from the circuit board, and the connecting plate is fixedly connected with the shell.

20. The circuit board fixing structure according to Claim 16, wherein The circuit board is provided with a first operation hole, and the limiting protrusion is provided with a second operation hole which can communicate with the first operation hole.

21. The circuit board fixing structure according to any one of claims 16 to 20, characterized by, The materials of the first connecting piece and the second connecting piece are both conductive materials.

22. The circuit board fixing structure according to Claim 1, wherein The first connecting piece is threadedly connected with the shell; or, the first connecting piece is press riveted with the shell; or, the first connecting piece is welded with the shell.

23. A power converter, comprising: The circuit board fixing structure of any one of claims 1 to 22 is included.

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