Chip inductor and production process thereof

Abstract

The invention relates to the technical field of electronic elements, and particularly discloses a chip inductor and a production process thereof. The chip inductor comprises an I-shaped magnetic core and a winding coil, the I-shaped magnetic core comprises an electrode blade, a middle column and a printing blade which are connected in sequence, a working surface is arranged at one end, far away from the middle column, of the electrode blade, an edge fillet is arranged on the edge of the working surface, a wire groove is concavely formed in the working surface, the groove bottom of the wire groove and the side wall of the wire groove are in transition through a groove bottom fillet, and the side wall of the wire groove and the working surface are in transition through a groove top fillet; two electrodes are arranged on the electrode blade, and at least parts of the electrodes are arranged in the wire slots; the winding coil comprises an enamelled wire wound on the middle column, two lead ends of the winding coil are connected to the electrode blades in a penetrating mode and extend into a groove cavity of the wire groove from the groove bottom of the wire groove, and each lead end is electrically connected with one electrode. According to the chip inductor, the welding fillets are formed on the I-shaped magnetic core, so that the continuity of a metallization layer on the I-shaped magnetic core is guaranteed, and the adhesive force of the electrodes is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic components, and in particular to a chip inductor and a production process thereof. Background Art

[0002] At present, the basic production process of coated bottom-welded power inductors includes the steps of winding (i.e. winding the coil on the magnetic core), welding electrodes and applying glue. As the core substrate of the inductor, the importance of the magnetic core is self-evident. The shape of the magnetic core is I-shaped, the coil is wound on the core column, and the starting line and the ending line are led out and hung on the electrode blades of the I-shaped magnetic core. They are combined with solder through welding process to form inductor electrodes for SMD patches. However, if the electrode blades of the magnetic core are only a simple plane, a series of problems will arise. First, it is difficult to firmly fix the coil only by hot dip welding, and the coil is prone to looseness. Secondly, the coplanarity of the product cannot be guaranteed, especially when the coil wire diameter is thick, the coplanarity problem is more prominent.

[0003] In the prior art, during the process of bottom welding of power inductors, the design of the core electrode blades is not completely flat. At the wire hanging position, a wire groove with a certain width and depth is concavely provided. Metallization treatment is performed on the wire groove, and the lead is hung inside the concave surface. Through hot dip welding, the coil is firmly fixed and a bottom welding electrode is formed. Among them, although the setting of the wire groove solves the problems of coil fixation and coplanarity, it also poses challenges to the continuity of the core metallization. The discontinuity of metallization may lead to uneven distribution of the inductor current, affect the working efficiency of the inductor, and to a certain extent weaken the adhesion between the electrode and the base material, reducing the reliability of the product.

[0004] Therefore, ensuring the continuity of the metallization of the inductor core is an important issue that needs to be urgently addressed in the current production of coated power inductors. Summary of the invention

[0005] The purpose of the present invention is to provide a chip inductor and a production process thereof, to achieve an optimized design of an I-shaped magnetic core, to form a welding fillet, to help ensure the continuity of a metallization layer on the I-shaped magnetic core, and at the same time to increase the welding area of ​​the chip inductor on a PCB and improve the adhesion of the electrode.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] A chip inductor comprises an I-shaped magnetic core and a winding coil; the I-shaped magnetic core comprises an electrode blade, a center column and a printing blade connected in sequence, the electrode blade is provided with a working surface at one end away from the center column, the edge of the working surface is provided with an edge chamfer, the working surface is concavely provided with a wire groove, the groove bottom of the wire groove and the side wall of the wire groove are transitioned through the groove bottom chamfer, the side wall of the wire groove and the working surface are transitioned through the groove top chamfer, two electrodes are provided on the electrode blade, and the electrodes are at least partially placed in the wire groove; the winding coil comprises an enameled wire wound on the center column, two lead ends of the winding coil are connected to the electrode blade and extend from the groove bottom of the wire groove into the groove cavity of the wire groove, and each of the lead ends is electrically connected to one of the electrodes.

[0008] As an optional technical solution for the patch inductor, the opening of the wire slot gradually expands in the direction from the bottom of the wire slot to the top of the wire slot, and the angle between the bottom of the wire slot and the side wall of the wire slot is θ, θ≥135°.

[0009] As an optional technical solution for the chip inductor, the distance from the top of the wire slot to the edge of the working surface is equal everywhere; the radius of the edge chamfer is R1, 0.05 mm ≤ R1 < K, wherein K is the smaller of a and b-R3 / (tanθ / 2), a is the thickness of the electrode blade in a direction perpendicular to the working surface, and b is the distance from the top of the wire slot to the edge of the working surface.

[0010] As an optional technical solution for the chip inductor, the radius of the chamfered corner at the bottom of the slot is R2, the radius of the chamfered corner at the top of the slot is R3, and R2=R3.

[0011] As an optional technical solution for the chip inductor, 0.05 mm ≤ R2 < J, wherein J is the smaller value of h / sinθ and c·tan(θ / 2) / 2, h is the depth of the wire slot, and c is the width of the bottom of the wire slot.

[0012] As an optional technical solution for the chip inductor, the groove wall of the wire groove, the working surface and the side surface of the electrode blade are all provided with a continuous and unbroken metallization layer.

[0013] As an optional technical solution for the chip inductor, the material of the I-shaped magnetic core is ferrite.

[0014] The chip inductor production process is used to manufacture the above-mentioned chip inductor, including the following steps:

[0015] S10: manufacturing the I-shaped magnetic core by a mold forming method;

[0016] S20: processing the edge chamfer on the edge of the working surface of the I-shaped magnetic core, and processing the groove bottom chamfer and the groove top chamfer at the wire groove;

[0017] S30: forming a metallization layer on the groove wall of the wire groove, the working surface and the side surface of the electrode blade;

[0018] S40: installing a winding coil on the center column, performing tinning treatment on the groove wall of the wire groove, the working surface and the side surface of the electrode blade, and applying glue on the surface of the winding coil to form a glue layer.

[0019] As an optional technical solution for the production process of the patch inductor, the metallization layer includes a first metallization layer, and S30 includes the following detailed steps:

[0020] S31: preparing metal paste and an inductor embryo, pad printing the metal paste onto the inductor embryo, and sintering to solidify the metal paste to form a first metallization layer.

[0021] As an optional technical solution for the production process of the patch inductor, the metallization layer further includes a second metallization layer and a third metallization layer, the second metallization layer is formed on the first metallization layer, and the third metallization layer is formed on the second metallization layer; after S31, the following steps are also included:

[0022] S32: forming the second metallization layer by electroplating;

[0023] S33: forming the third metallization layer by electroplating.

[0024] Beneficial effects of the present invention:

[0025] The chip inductor uses the design of the lead end plugged into the wire slot to ensure a stable connection between the electrode and the winding coil, improve the reliability of the electrical connection, and reduce the failure rate. The structure of the rounded corners at the bottom of the slot and the top of the slot on the electrode blade can improve the adhesion of the electrode in the slot, optimize the connection between the electrode and the winding coil, and ensure the stability of current transmission. The electrical connection between the electrode and the lead end makes the connection between the internal components of the chip inductor more secure and reduces the probability of failure. Moreover, by setting the edge rounded corners, the rounded corners at the bottom of the slot and the rounded corners at the top of the slot, the difficulty of forming the metallization layer on the surface of the electrode blade is reduced, it is not easy to cause cold soldering and has good conductivity, which can improve the problem of discontinuity of the metallization layer and help improve the reliability of the chip inductor. The structural improvement of the rounded corners helps to increase the welding area of ​​the chip inductor when it is installed on the external component, and improves the ability to resist mechanical shock. At the same time, the winding coil set on the center column ensures the inductive effect of the chip inductor. Combined with the above-mentioned optimized design of the I-shaped magnetic core structure, it can provide excellent inductive performance and higher working efficiency, effectively improve the efficiency and stability of the chip inductor, and achieve efficient electrical signal conversion and stable inductive performance.

[0026] The chip inductor production process uses mold forming to produce I-shaped cores, which improves production efficiency and the quality of the I-shaped cores and ensures structural consistency. The I-shaped cores are processed by edge rounding, slot bottom rounding and slot top rounding to ensure that the surface of the I-shaped core is smooth and reduce the defective rate in production. The conductivity and stability of the chip inductor are enhanced by the formation of multiple layers of metallization. The processes of installing the winding coil on the center column, gluing the winding coil, and tinning the surface of the electrode blades in multiple places can ensure that the bottom and side electrodes of the slot wall, working surface and side of the electrode blade are continuously and seamlessly formed, so as to achieve reliable sealing of the glue layer on the winding coil. The planning of the above steps realizes efficient and accurate production of chip inductors, completes the process refinement and product quality improvement, and makes the production process more standardized and efficient. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] Figure 1 is a cross-sectional view of a chip inductor provided by an embodiment of the present invention;

[0028] Figure 2 is a cross-sectional view of an I-shaped magnetic core provided by an embodiment of the present invention;

[0029] Figure 3 yes Figure 2 A partial enlarged view of middle A.

[0030] In the figure:

[0031] 100, I-shaped magnetic core; 110, electrode blade; 1101, edge rounding; 111, wire slot; 1111, slot bottom rounding; 1112, slot top rounding; 120, center column; 130, printing blade; 200, glue layer; 300, lead end; 400, electrode; 510, first metallization layer; 520, second metallization layer; 530, third metallization layer. DETAILED DESCRIPTION

[0032] The technical solution of the present invention will be described clearly and completely below in conjunction with the accompanying drawings. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0033] In the description of the present invention, it should be noted that the orientations or positional relationships indicated by the terms "center", "up", "down", "left", "right", "vertical", "horizontal", "inside", "outside", etc. are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying 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 limiting the present invention. In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. Among them, the terms "first position" and "second position" are two different positions, and the first feature "above", "above" and "above" the second feature include the first feature being directly above and obliquely above the second feature, or simply indicates that the first feature is higher in level than the second feature. The first feature "below", "below" and "below" the second feature include the first feature being directly below and obliquely below the second feature, or simply indicates that the first feature is lower in level than the second feature.

[0034] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0035] Embodiments of the present invention are described in detail below, examples of which are shown in the accompanying drawings, wherein the same or similar reference numerals throughout represent the same or similar elements or elements having the same or similar functions. The embodiments described below with reference to the accompanying drawings are exemplary and are only used to explain the present invention, and cannot be understood as limiting the present invention.

[0036] like Figures 1 to 3 As shown, the present embodiment provides a chip inductor, including an I-shaped magnetic core 100 and a winding coil; the I-shaped magnetic core 100 includes an electrode blade 110, a center column 120 and a printing blade 130 connected in sequence, the electrode blade 110 is provided with a working surface at one end away from the center column 120, the edge of the working surface is provided with an edge chamfer 1101, the working surface is concavely provided with a wire groove 111, the groove bottom of the wire groove 111 and the side wall of the wire groove 111 are transitioned through the groove bottom chamfer 1111, the side wall of the wire groove 111 and the working surface are transitioned through the groove top chamfer 1112, two electrodes 400 are provided on the electrode blade 110, and the electrode 400 is at least partially placed in the wire groove 111; the winding coil includes an enameled wire wound on the center column 120, and the two lead ends 300 of the winding coil are connected to the electrode blade 110 and extend from the groove bottom of the wire groove 111 into the groove cavity of the wire groove 111, and each lead end 300 is electrically connected to an electrode 400. Specifically, the lead end 300 is made of copper.

[0037] The chip inductor is designed to be plugged into the wire slot 111 by the lead end 300, so that the electrode 400 is firmly connected to the winding coil, which improves the reliability of the electrical connection and reduces the failure rate. The structure of the groove bottom rounded corner 1111 and the groove top rounded corner 1112 on the electrode blade 110 can improve the adhesion of the electrode 400 in the groove 111, optimize the connection between the electrode 400 and the winding coil, and ensure the stability of current transmission. The electrical connection between the electrode 400 and the lead end 300 makes the connection between the internal components of the chip inductor more secure and reduces the probability of failure. Moreover, by setting the edge rounded corner 1101, the groove bottom rounded corner 1111 and the groove top rounded corner 1112, the difficulty of forming the metallization layer on the surface of the electrode blade 110 is reduced, it is not easy to cause cold welding and has good electrical conductivity, which can improve the problem of discontinuity of the metallization layer and help improve the reliability of the chip inductor. The structural improvement of the rounded corner helps to increase the welding area of ​​the chip inductor when it is installed on the external component, and improves the ability to resist mechanical impact. At the same time, the winding coil arranged on the center column 120 ensures the inductive effect of the chip inductor. Combined with the above-mentioned optimized design of the I-shaped magnetic core 100 structure, it can provide excellent inductive performance and higher working efficiency, effectively improve the efficiency and stability of the chip inductor, and achieve efficient electrical signal conversion and stable inductive performance.

[0038] When the chip inductor with excellent continuity of the metallization layer provided in this embodiment is soldered to a PCB board, a smooth solder fillet is formed to increase the soldering area of ​​the chip inductor on the PCB, thereby significantly enhancing the adhesion of the chip inductor to external components and greatly improving its ability to resist mechanical shock.

[0039] In this embodiment, the opening of the wire groove 111 gradually expands in the direction from the groove bottom to the groove top of the wire groove 111, and the angle between the groove bottom of the wire groove 111 and the side wall of the wire groove 111 is θ, and θ≥135°.

[0040] The opening of the wire slot 111 gradually expands from the bottom of the slot to the top of the slot, and the angle θ between the bottom of the slot and the side wall is ≥135°. The above design simplifies the specific structure of the wire slot 111, reduces the difficulty of setting the electrode 400 in the wire slot 111, and improves the stability and reliability of the chip inductor. The angle between the bottom of the slot and the side wall is limited. This structure can effectively reduce resistance and improve the heat dissipation performance of the chip inductor, thereby improving the overall service life and stability.

[0041] If the size of the fillet is set too small, it is easy to cause the I-shaped magnetic core 100 to have a chip defect; if the size is too large, it will reduce the magnetic circuit area, thereby adversely affecting the inductance of the chip inductor. In addition, each fillet has a certain mutual restriction relationship with other structural elements of the I-shaped magnetic core 100 (such as the thickness of the electrode blade 110 and the depth of the wire slot 111). At the same time, there are also mutual restrictions between different fillets, which need to be comprehensively considered to ensure the rationality of the overall design.

[0042] Furthermore, the spacing from the top of the wire groove 111 to the edge of the working surface is equal everywhere; the radius of the edge chamfer 1101 is R1, 0.05 mm ≤ R1 < K, where K is the smaller value of a and b-R3 / (tanθ / 2), a is the thickness of the electrode blade 110 in the direction perpendicular to the working surface, and b is the spacing from the top of the wire groove 111 to the edge of the working surface.

[0043] By precisely controlling the thickness of the electrode blade 110, the spacing from the top of the wire slot 111 to the edge of the working surface, and the radius R1 of the edge fillet 1101, the smoothness of the working surface is ensured, electromagnetic interference can be effectively prevented, the stability of the patch inductor is improved, and the mechanical impact resistance of the patch inductor is enhanced, thereby achieving a perfect combination of the electrode blade 110 and the working surface, which not only ensures the efficiency of current transmission, but also reduces production costs, improves product qualification rate, and extends service life. Among them, the equal spacing from the top of the wire slot 111 to the edge of the working surface ensures the uniformity of the patch inductor. At the same time, the design of the edge fillet 1101 can effectively reduce stress concentration, thereby improving the durability of the electrode blade 110.

[0044] Exemplarily, the radius of the groove bottom fillet 1111 is R2, the radius of the groove top fillet 1112 is R3, and R2=R3.

[0045] By setting the radius R2 of the groove bottom fillet 1111 and the radius R3 of the groove top fillet 1112 to be equal, the internal structure of the patch inductor is optimized, the durability of the overall structure is enhanced, the consistency of the process and the symmetry of the structure are achieved, the overall structure of the patch inductor is more compact, the eddy current loss is further reduced, and the operating efficiency and stability of the patch inductor are improved. The above improvements also help to simplify the production process and improve production efficiency.

[0046] Furthermore, 0.05 mm ≤ R2 < J, wherein J is the smaller value of h / sinθ and c·tan(θ / 2) / 2, h is the depth of the wire groove 111 , and c is the width of the bottom of the wire groove 111 .

[0047] By precisely controlling R2 and R3, the integrity and strength of the internal structure of the wire slot 111 can be ensured, making the design of the wire slot 111 more reasonable, which not only ensures the performance of the chip inductor, but also avoids technical difficulties in the production process, and improves the controllability of production and product quality.

[0048] In this embodiment, the groove wall, the working surface of the wire groove 111 and the side surface of the electrode blade 110 are all provided with a continuous and seamless metallization layer.

[0049] The continuous and seamless metallization layer is used to cover the I-shaped magnetic core 100 and the wire slot 111, which improves the conductivity and stability of the chip inductor and enhances the durability and corrosion resistance of the chip inductor. At the same time, this process simplifies the production process, improves production efficiency, and increases the safety performance and service life of the chip inductor.

[0050] Exemplarily, the material of the I-shaped magnetic core 100 is ferrite.

[0051] The I-shaped magnetic core 100 made of ferrite material has high magnetic permeability and stability, can improve the inductive efficiency and anti-interference ability of the chip inductor, and enhance the reliability and accuracy of the product.

[0052] In this embodiment, a coated power inductor with an I-shaped magnetic core 100 of 6.00 mm×6.00 mm×4.50 mm, R1=0.10 mm, R2=0.10 mm, R3=0.10 mm and θ=135° is taken as an example. Compared with a traditional coated inductor, the metallization layer of the traditional coated inductor generally has faults.

[0053] The reliability test items include terminal strength and mechanical impact tests. The test conditions for terminal strength are: perform three reflow pretreatments, and use a fixture to push with a force of 17.70 Newtons for 59.00-61.00 seconds in two mutually perpendicular directions (the radius of the fixture's pusher head is 0.50 mm). The test results show that the chip inductor provided in this embodiment meets the test requirements, while the traditional coated inductor does not meet the test requirements.

[0054] The test conditions of the mechanical shock test are: the following three half-sine wave shock tests are carried out in three groups:

[0055] 1) Peak acceleration is 100g, pulse width is 6.00 milliseconds half sine wave;

[0056] 2) A half-sine wave with a peak acceleration of 2000g and a pulse width of 0.30 milliseconds;

[0057] 3) Peak acceleration is 3000g, pulse width is 0.30ms half sine wave.

[0058] In the XYZ three-dimensional space, the above half-sine wave is emitted from six different directions, namely ±X, ±Y and ±Z. Each set of experiments is emitted three times in each direction, for a total of eighteen times.

[0059] The test results show that the chip inductor provided in this embodiment meets the test requirements, while the traditional coated inductor does not meet the test requirements.

[0060] The chip inductor provided in this embodiment has a terminal design with a non-fracture structure, and therefore has stronger terminal strength and higher resistance to mechanical impact, thereby showing more stable and reliable performance in practical applications.

[0061] This embodiment also provides a chip inductor production process for manufacturing the above-mentioned chip inductor, including the following steps:

[0062] Step 1: Using a mold forming method to make an I-shaped magnetic core 100.

[0063] Step 2: Processing edge chamfers 1101 on the edge of the working surface of the I-shaped magnetic core 100 , and processing groove bottom chamfers 1111 and groove top chamfers 1112 at the line groove 111 .

[0064] Step 3: forming a metallization layer on the slot wall, the working surface of the slot 111 and the side surface of the electrode blade 110 .

[0065] Step 4: Install the winding coil on the center column 120 , perform tinning treatment on the slot wall, working surface and side surface of the wire slot 111 and electrode blade 110 , and apply glue on the surface of the winding coil to form a glue layer 200 .

[0066] The chip inductor production process manufactures the I-shaped magnetic core 100 by mold forming, which improves the production efficiency and the quality of the I-shaped magnetic core 100 and ensures the consistency of the structure. The I-shaped magnetic core 100 is processed with edge rounding 1101, groove bottom rounding 1111 and groove top rounding 1112 to ensure that the surface of the I-shaped magnetic core 100 is smooth and reduce the defective rate in production. The conductivity and stability of the chip inductor are enhanced by the formation of multiple metallization layers. The processes of installing the winding coil on the middle column 120, coating the winding coil with glue, and tinning the surface of the electrode blade 110 at multiple locations can ensure that the groove wall, working surface and side surface of the wire groove 111 of the electrode blade 110 form a continuous and seamless bottom surface and side electrodes, so as to achieve reliable sealing of the glue layer 200 to the winding coil. The planning of the above steps realizes efficient and accurate production of chip inductors, completes the process refinement and product quality improvement, and makes the production process more standardized and efficient.

[0067] In this embodiment, the metallization layer includes a first metallization layer 510 , and step three includes the following detailed steps: preparing metal paste and an inductor body, pad printing the metal paste onto the inductor body, and sintering to solidify the metal paste to form the first metallization layer 510 .

[0068] By preparing metal paste, pad printing and sintering, a continuous and non-fractured first metallization layer 510 is formed. This solution ensures the bonding force between the metallization layer and the electrode blade 110, making the metallization layer more uniform and dense, thereby improving the electrical performance and corrosion resistance of the chip inductor, and ensuring the feasibility of the chip inductor production process and the stability of the product. The above detailed steps not only enhance the conductivity of the chip inductor, but also ensure the close bonding between the metallization layers, avoiding the appearance of a fault structure.

[0069] Furthermore, the metallization layer also includes a second metallization layer 520 and a third metallization layer 530, the second metallization layer 520 is formed on the first metallization layer 510, and the third metallization layer 530 is formed on the second metallization layer 520; after sintering to solidify the metal slurry to form the first metallization layer 510, the following steps are also included: electroplating to form the second metallization layer 520; electroplating to form the third metallization layer 530.

[0070] The second metallization layer 520 and the third metallization layer 530 are formed continuously and without discontinuities by electroplating. This solution ensures the bonding strength between the metallization layers and further improves the electrical performance and corrosion resistance of the chip inductor.

[0071] In one implementation of this embodiment, the material of the first metallization layer 510 is silver, and the metal paste is silver paste; the material of the second metallization layer 520 is nickel; and the material of the third metallization layer 530 is tin.

[0072] The first metallization layer 510 is made of silver, which has excellent conductivity and oxidation resistance, and plays a role in reducing resistance; the second metallization layer 520 is made of nickel, which enhances overall adhesion and corrosion resistance; the third metallization layer 530 is made of tin, which enhances weldability and product reliability, ensures good welding performance, and optimizes the process of chip inductor production technology. The different material selections of the first metallization layer 510, the second metallization layer 520, and the third metallization layer 530 provide different performance optimization options for the chip inductor, allowing the chip inductor to adapt to different application scenarios.

[0073] In other implementations of this embodiment, only the materials of at most two of the first metallization layer 510 , the second metallization layer 520 , and the third metallization layer 530 are limited.

[0074] Obviously, the above embodiments of the present invention are merely examples for clearly illustrating the present invention, and are not intended to limit the embodiments of the present invention. For those skilled in the art, other different forms of changes or modifications can be made based on the above description. It is not necessary and impossible to list all the embodiments here. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included in the protection scope of the claims of the present invention.

Claims

1. Chip inductor, characterized in that: include: An I-shaped magnetic core (100) comprises an electrode blade (110), a center column (120) and a printing blade (130) connected in sequence, wherein a working surface is provided at one end of the electrode blade (110) away from the center column (120), an edge of the working surface is provided with an edge rounding (1101), a wire groove (111) is concavely provided on the working surface, a groove bottom of the wire groove (111) and a side wall of the wire groove (111) transition through a groove bottom rounding (1111), and a side wall of the wire groove (111) and the working surface transition through a groove top rounding (1112), and two electrodes (400) are provided on the electrode blade (110), and the electrodes (400) are at least partially disposed in the wire groove (111); A winding coil comprises an enameled wire wound on the center column (120), wherein two lead ends (300) of the winding coil are connected to the electrode blades (110) and extend from the bottom of the wire slot (111) into the slot cavity of the wire slot (111), and each of the lead ends (300) is electrically connected to one of the electrodes (400).

2. The chip inductor according to claim 1, characterized in that: In a direction from the bottom of the wire trough (111) to the top of the wire trough (111), the opening of the wire trough (111) gradually expands, and an angle between the bottom of the wire trough (111) and a side wall of the wire trough (111) is θ, and θ≥135°.

3. The chip inductor according to claim 2, characterized in that: The distance from the top of the wire groove (111) to the edge of the working surface is equal everywhere; the radius of the edge chamfer (1101) is R1, 0.05 mm ≤ R1 < K, wherein K is the smaller value of a and b-R3 / (tanθ / 2), a is the thickness of the electrode blade (110) in a direction perpendicular to the working surface, and b is the distance from the top of the wire groove (111) to the edge of the working surface.

4. The chip inductor according to claim 2, characterized in that: The radius of the groove bottom chamfer (1111) is R2, the radius of the groove top chamfer (1112) is R3, and R2=R3.

5. The chip inductor according to claim 4, characterized in that: 0.05 mm≤R2<J, wherein J is the smaller value of h / sinθ and c·tan(θ / 2) / 2, h is the groove depth of the wire groove (111), and c is the width of the groove bottom of the wire groove (111).

6. The chip inductor according to claim 1, characterized in that: The groove wall of the wire groove (111), the working surface and the side surface of the electrode blade (110) are all provided with a continuous and seamless metallization layer.

7. The chip inductor according to any one of claims 1 to 6, characterized in that: The material of the I-shaped magnetic core (100) is ferrite.

8. A chip inductor production process, used to manufacture the chip inductor according to any one of claims 1 to 7, characterized in that: The following steps are involved: S10: using a mold forming method to manufacture the I-shaped magnetic core (100); S20: processing the edge chamfer (1101) on the edge of the upper working surface of the I-shaped magnetic core (100), and processing the groove bottom chamfer (1111) and the groove top chamfer (1112) at the wire groove (111); S30: forming a metallization layer on the groove wall of the wire groove (111), the working surface and the side surface of the electrode blade (110); S40: installing a winding coil on the center column (120), performing tinning treatment on the groove wall of the wire groove (111), the working surface and the side surface of the electrode blade (110), and applying glue on the surface of the winding coil to form a glue layer (200).

9. The chip inductor production process according to claim 8, characterized in that: The metallization layer includes a first metallization layer (510), and S30 includes the following detailed steps: S31: preparing metal paste and an inductor embryo, pad printing the metal paste onto the inductor embryo, and sintering to solidify the metal paste to form a first metallization layer (510).

10. The chip inductor production process according to claim 9, characterized in that: The metallization layer further comprises a second metallization layer (520) and a third metallization layer (530), wherein the second metallization layer (520) is formed on the first metallization layer (510), and the third metallization layer (530) is formed on the second metallization layer (520); after S31, the following steps are further included: S32: forming the second metallization layer (520) by electroplating; S33: forming the third metallization layer (530) by electroplating.

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