SMD common mode inductor structure

Abstract

The utility model discloses an SMD (Surface Mount Device) common-mode inductor structure, which relates to the technical field of SMD and comprises a shell, a magnetic core positioned in the shell, a coil wound on the magnetic core, a pin fixing part positioned at the side end of the shell and a pin arranged on the pin fixing part, the pins comprise an upper pin fixedly arranged at the upper end of the pin fixing part and a lower pin fixedly arranged at the lower end of the pin fixing part, and the upper pin and the lower pin are integrally connected; the side end of the shell is provided with a lead hole corresponding to the upper pin, a lead of the coil penetrates through the lead hole and is connected with the upper pin, the upper pin is roughly vertically arranged, and the lower pin is flat; according to the design that the upper pins serve as top hitching leg soldering tin, the lower pins serve as bottom patches and the bottom is provided with the patches, the common-mode inductor can obtain a large-area supporting and contact plane on a circuit board, the situation of local suspension or unevenness is effectively reduced, the common-mode inductor does not need to be affected by hitching leg soldering tin, and therefore the flatness of a product is effectively guaranteed.

Description

Technical Field

[0001] The utility model relates to the technical field of SMD, in particular to an SMD common mode inductor structure. Background Technique

[0002] In the development process of electronic components, SMD (Surface Mounted Devices) has been widely used due to its advantages such as small volume, high performance, and convenient for automated production.

[0003] At present, for the BASE (substrate or bottom structure) part of the common mode inductor, it is usually connected to the PIN (pin) by using copper wire hanging feet and passing them through a tin furnace for conduction. However, this connection method has some problems. The position of the patch feet is easily deformed by the stress of the hanging feet. At the same time, the solder of the copper wire hanging feet adheres to the tin, affecting the flatness of the position of the patch feet, which will have an adverse impact on the coplanarity of the patch feet to a certain extent, that is, the patch feet cannot be in the same plane, resulting in the patch feet being unevenly attached and skewed.

[0004] This uneven and skewed situation may affect the installation effect and electrical performance of the common mode inductor on the circuit board; in this regard, it is necessary to propose an improved technical solution to solve the above problems. Content of the Utility Model

[0005] The utility model aims to provide a technical solution to solve the above problems in order to overcome the above deficiencies.

[0006] An SMD common mode inductor structure includes a housing, a magnetic core located inside the housing, a coil wound around the magnetic core, a pin fixing part located at the side end of the housing, and pins arranged on the pin fixing part. The pins include an upper pin fixedly arranged at the upper end of the pin fixing part and a lower pin fixedly arranged at the lower end of the pin fixing part, and the upper pin and the lower pin are integrally connected;

[0007] A lead hole corresponding to the upper pin is opened at the side end of the housing, and the lead of the coil passes through the lead hole and is connected to the upper pin. Among them, the upper pin is arranged substantially vertically, and the lower pin is in a flat shape.

[0008] As a further scheme of the utility model: the housing includes a square part and an annular part formed at the upper end of the square part. The annular part is within the vertical projection range of the square part, so that the pin fixing part misaligned with the annular part is formed at the corner position of the square part.

[0009] As a further scheme of the utility model: the square part and the annular part jointly form an annular groove, and the magnetic core and the coil thereon are both placed inside the annular groove.

[0010] As a further solution of the present utility model: the lead hole is communicated with the annular groove, and the lead hole is opened along the upper end surface of the annular part.

[0011] As a further solution of the present utility model: the lower pin includes a vertical portion fixed to the lower end of the pin fixing portion and a horizontal portion fixed to the lower end of the vertical portion, and the horizontal portion extends along the outside of the pin fixing portion / square portion.

[0012] As a further solution of the present utility model: a heat dissipation port acting on the annular groove is formed at the lower end of the square portion through the lower pin.

[0013] As a further solution of the present utility model: the magnetic core is annular, and the magnetic core is made of ferrite.

[0014] As a further solution of the present utility model: a positioning structure is provided between the magnetic core and the housing to fix the magnetic core in the housing through the positioning structure.

[0015] As a further solution of the present utility model: the connection mode between the upper pin and the coil lead is welding.

[0016] As a further solution of the present utility model: the housing is made of plastic or epoxy resin.

[0017] Compared with the prior art, the beneficial effects of the present utility model are as follows:

[0018] 1) Through the setting of the pin fixing portion, and the pins provided on the pin fixing portion are divided into upper pins placed at the upper end and lower pins placed at the lower end. The upper pins are used for soldering the top hanging feet, and the lower pins are used for bottom soldering pads. The design of the bottom soldering pads enables the common mode inductor to obtain a large-area support and contact plane on the circuit board. This large-area contact helps to disperse the pressure, enables the common mode inductor to fit more evenly on the surface of the circuit board, reduces the situation of local suspension or unevenness, and is not affected by the hanging foot soldering. Thus, it effectively guarantees the flatness of the product, and at the same time, the lower pins do not need to be tinned, avoiding the influence caused by soldering, which is beneficial to the appearance neatness;

[0019] 2) The design of the top hanging foot soldering provides a certain fixing and restraint in the vertical direction. The hanging foot soldering can limit the movement and shaking of the common mode inductor in the top direction. Combined with the support of the bottom soldering pads, a stable installation structure is formed;

[0020] 3) The bottom soldering pads are in large-area contact with the circuit board, which is beneficial to the rapid conduction of heat to the circuit board. The top hanging foot soldering also increases a certain heat dissipation area, thereby improving the heat dissipation effect of the common mode inductor and helping to maintain its performance and reliability;

[0021] 4) The bottom patch can be quickly and accurately installed on the circuit board by a machine, while the soldering of the top hanging pins can be carried out in subsequent processes, improving the production efficiency and consistency, thus facilitating the improvement of the assembly efficiency.

[0022] Additional aspects and advantages of the present utility model will be given in part in the following description, become apparent in part from the following description, or be learned through the practice of the present utility model. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In order to more clearly illustrate the technical solutions in the embodiments of the present utility model or the prior art, the following will briefly introduce the drawings required for use in the description of the embodiments or the prior art. Obviously, the drawings in the following description are only some embodiments of the present utility model. For those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0024] Figure 1 is a three-dimensional structural schematic diagram of one perspective of the present utility model;

[0025] Figure 2 is a three-dimensional structural schematic diagram of another perspective of the present utility model;

[0026] Figure 3 is a front view structural schematic diagram of the present utility model.

[0027] The reference numerals and names in the drawings are as follows:

[0028] 1, housing; 2, magnetic core; 3, coil; 4, pin fixing part; 5, upper pin; 6, lower pin; 7, square part; 8, annular part; 9, annular groove; 10, heat dissipation port; 11, lead hole; 12, vertical part; 13, horizontal part. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0029] The following will clearly and completely describe the technical solutions in the embodiments of the present utility model with reference to the drawings in the embodiments of the present utility model. Obviously, the described embodiments are only some embodiments of the present utility model, rather than all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative efforts belong to the scope of protection of the present utility model.

[0030] Please refer to Figures 1-3, in the embodiment of the present utility model, a structure of an SMD common mode inductor includes a housing 1, a magnetic core 2 located inside the housing 1, a coil 3 wound around the magnetic core 2, a pin fixing part 4 located at the side end of the housing 1, and pins arranged on the pin fixing part 4. The pins include an upper pin 5 fixedly arranged at the upper end of the pin fixing part 4 and a lower pin 6 fixedly arranged at the lower end of the pin fixing part 4. The upper pin 5 and the lower pin 6 are integrally connected;

[0031] A lead hole 11 corresponding to the upper pin 5 is opened at the side end of the housing 1. The lead of the coil 3 passes through the lead hole 11 and is connected to the upper pin 5. Among them, the upper pin 5 is arranged substantially vertically, and the lower pin 6 is in a flat shape.

[0032] In the technical solution of the present utility model, through the setting of the pin fixing part 4, the pins arranged on the pin fixing part 4 are divided into an upper pin 5 placed at the upper end and a lower pin 6 placed at the lower end. The upper pin 5 is used for soldering the top hanging pin, and the lower pin 6 is used for bottom soldering. The design of the bottom soldering enables the common mode inductor to obtain a large-area support and contact plane on the circuit board. This large-area contact helps to disperse the pressure, enables the common mode inductor to fit more evenly on the surface of the circuit board, reduces the situation of local suspension or unevenness, and is not affected by the soldering of the hanging pin, thereby effectively ensuring the flatness of the product. At the same time, the lower pin 6 does not need to be tinned, avoiding the influence caused by soldering, and being beneficial to the appearance neatness; the design of the top hanging pin soldering provides a certain fixing and restraint in the vertical direction. The hanging pin soldering can limit the movement and shaking of the common mode inductor in the top direction. Combined with the support of the bottom soldering, a stable installation structure is formed;

[0033] The bottom soldering is in large-area contact with the circuit board, which is beneficial to the rapid conduction of heat to the circuit board. The top hanging pin soldering also increases a certain heat dissipation area, thereby improving the heat dissipation effect of the common mode inductor and helping to maintain its performance and reliability; the bottom soldering can be quickly and accurately installed on the circuit board by a machine, and the top hanging pin soldering can be carried out in subsequent processes, improving the production efficiency and consistency, and thus being beneficial to improving the assembly efficiency.

[0034] In the embodiment of the present utility model, the housing 1 includes a square part 7 and an annular part 8 formed at the upper end of the square part 7. The annular part 8 is within the vertical projection range of the square part 7, so that the pin fixing part 4 in which the end corners of the square part 7 are misaligned with the annular part 8 is formed.

[0035] Through the structural design of the housing 1, that is, the combination of the bottom square part 7 and the upper annular part 8, and through the design that the annular part 8 is within the vertical projection range of the square part 7, the end corners of the square part 7 can protrude and be misaligned relative to the annular part 8, thereby forming a pin fixing part 4, enabling the upper pin 5 and the lower pin 6 to be supported, and enabling the upper pin 5 to be generally received within the vertical projection range of the square part 7, which is conducive to a neat appearance and does not hinder the grasping of automatic chip mounting.

[0036] In the embodiment of the present utility model, the square part 7 and the annular part 8 jointly form an annular groove 9, and the magnetic core 2 and the coil 3 thereon are both disposed inside the annular groove 9.

[0037] In the embodiment of the present utility model, the lead hole 11 is communicated with the annular groove 9, and the lead hole 11 is opened along the upper end surface of the annular part 8.

[0038] Through this setting, the lead hole 11 can form a heat dissipation channel communicated with the annular groove 9, which is conducive to the overall heat dissipation performance.

[0039] In the embodiment of the present utility model, the lower pin 6 includes a vertical part 12 fixed to the lower end of the pin fixing part 4 and a horizontal part 13 fixed to the lower end of the vertical part 12, and the horizontal part 13 extends along the outside of the pin fixing part 4 / square part 7.

[0040] That is, the vertical part 12 and the horizontal part 13 can integrally form a flat structure, which is conducive to bottom chip mounting and flatness.

[0041] In the embodiment of the present utility model, the lower end of the square part 7 forms a heat dissipation port 10 acting on the annular groove 9 through the lower pin 6.

[0042] Due to being supported by the lower pin 6 and combined with the structural features of the vertical part 12 and the horizontal part 13 of the lower pin 6, a heat dissipation port 10 acting on the annular groove 9 can be formed in the corresponding orientation of the lower pin 6. On the basis of ensuring the feasibility of the bottom chip mounting and the top pin soldering scheme, it is also effectively conducive to the overall heat dissipation performance.

[0043] In the embodiment of the present utility model, the magnetic core 2 is annular, and among them, the magnetic core 2 is made of ferrite.

[0044] In the embodiment of the present utility model, a positioning structure is provided between the magnetic core 2 and the housing 1 to fix the magnetic core 2 in the housing 1 through the positioning structure.

[0045] The positioning structure can be a snap - fit method of a bayonet and a slot, or glue bonding, or other methods.

[0046] In the embodiment of the present utility model, the connection mode between the upper pin 5 and the lead of the coil 3 is welding.

[0047] In the embodiment of the present utility model, the housing 1 is made of plastic or epoxy resin.

[0048] For those skilled in the art, it is obvious that the present utility model is not limited to the details of the above-described exemplary embodiments, and without departing from the spirit or basic characteristics of the present utility model, the present utility model can be implemented in other specific forms. Therefore, from any point of view, the embodiments should be regarded as exemplary and non-limiting. The scope of the present utility model is defined by the appended claims rather than the above description. Therefore, it is intended to embrace all changes within the meaning and scope of the equivalent elements of the claims in the present utility model.

Claims

1. A SMD common mode inductor structure, characterized in that: The invention comprises a shell, a magnetic core located in the shell, a coil wound on the magnetic core, a pin fixing part located at a side end of the shell, and pins arranged on the pin fixing part, wherein the pins comprise an upper pin fixedly arranged at an upper end of the pin fixing part and a lower pin fixedly arranged at a lower end of the pin fixing part, and the upper pin and the lower pin are connected as one piece; A lead hole corresponding to the upper pin is opened at the side end of the shell, and the lead wire of the coil passes through the lead hole and is connected to the upper pin, wherein the upper pin is substantially vertically arranged and the lower pin is flat.

2. The SMD common mode inductor structure according to claim 1, characterized in that: The housing includes a square portion and an annular portion formed at the upper end of the square portion, wherein the annular portion is located within the vertical projection range of the square portion so that the end angle position of the square portion forms the pin fixing portion which is offset from the annular portion.

3. The SMD common mode inductor structure according to claim 2, characterized in that: The square portion and the annular portion together form an annular groove, and the magnetic core and the coil thereon are both built in the annular groove.

4. The SMD common mode inductor structure according to claim 3, characterized in that: The lead-in hole is communicated with the annular groove, and the lead-in hole is opened along the upper end surface of the annular portion.

5. The SMD common mode inductor structure according to claim 3, characterized in that: The lower pin includes a vertical portion fixed at the lower end of the pin fixing portion and a horizontal portion fixed at the lower end of the vertical portion, and the horizontal portion is extended along the outer side of the pin fixing portion / square portion.

6. The SMD common mode inductor structure according to claim 5, characterized in that: The lower end of the square portion forms a heat dissipation opening acting on the annular groove through a lower pin.

7. The SMD common mode inductor structure according to claim 1, characterized in that: The magnetic core is annular in shape, and is made of ferrite.

8. The SMD common mode inductor structure according to claim 1, characterized in that: A positioning structure is arranged between the magnetic core and the shell, so that the magnetic core is fixed in the shell through the positioning structure.

9. The SMD common mode inductor structure according to claim 1, characterized in that: The upper pin and the coil lead are connected by welding.

10. The SMD common mode inductor structure according to claim 1, characterized in that: The shell is made of plastic or epoxy resin.

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