Anti-interference filter and manufacturing method thereof

Abstract

The invention discloses an anti-interference filter and a manufacturing method thereof, the anti-interference filter comprises a plastic base, a core-through magnetic bead, capacitors, a metal plate and core-through capacitors, the capacitors of four electrodes and the core-through magnetic bead are placed in a groove formed in the top of the plastic base, and the core-through capacitors are arranged at the bottom and fixed by the metal plate; and the four electrodes penetrate through the three core-penetrating magnetic beads, the core-penetrating capacitor and the metal plate, and the process method is a process of firstly welding and then potting. According to the invention, stable and reliable installation of the through-core magnetic bead, the capacitor and the through-core capacitor can be realized, and mutual interference is eliminated; according to the manufacturing method, performance reduction of the anti-interference filter product is avoided.

Description

Technical Field

[0001] The invention belongs to the technical field of anti-interference filters, relates to an anti-interference filter, and also relates to a manufacturing method of the anti-interference filter. Background Art

[0002] The anti-interference filter is composed of 3 inductors and 2 capacitors. The structure adopts a conventional inner cavity layout. The structure is too close to eliminate mutual interference, and it is inconvenient to weld the inductors. The anti-interference filter is encapsulated with epoxy resin and then the product leads are soldered. During the soldering process, the flux climbs along the lead through-hole position to the inside of the anti-interference filter product when encountering high temperature. Since the surface of the anti-interference filter product is fully encapsulated with epoxy resin, the internal flux cannot be cleaned, and the flux residues (such as halides, organic acids, etc.) have certain corrosion, resulting in a decrease in the insulation performance of the product. Summary of the invention

[0003] The first invention objective of the present invention is to provide an anti-interference filter that can achieve stable and reliable installation of through-core magnetic beads, capacitors, and through-core capacitors, eliminating mutual interference; The second invention objective of the present invention is to provide a method for manufacturing an anti-interference filter to avoid degradation of the performance of the anti-interference filter product.

[0004] The technical solution adopted by the present invention is: an anti-interference filter, including a plastic base, a through-core magnetic bead, a capacitor, a metal plate and a through-core capacitor, a groove is arranged on the top of the plastic base, three step holes and a small through hole are arranged at the bottom of the groove, three through-core magnetic beads are used, and they are respectively placed in the three step holes, four electrodes are welded at the bottom of the capacitor, the four electrodes respectively pass through the three inner holes and the small through holes of the three through-core magnetic beads, and the capacitor is close to the top surface of the through-core magnetic bead, and the top groove is filled with potting glue, an electrode close to the through-core magnetic bead is not installed through the plastic base and then sleeved with the through-core capacitor, the bottom of the plastic base uses a metal clamping piece to clamp and fix the metal plate and the through-core capacitor passes through the metal plate, four electrodes are led out of the metal plate, and the electrodes led out of the small through hole are electrically connected to the metal plate.

[0005] Furthermore, the above-mentioned metal clamping part is a clamping strip structure, and two symmetrical clamping strips facing upward are arranged in the middle of the two upper ends, and a limiting convex strip is arranged in the center. The two clamping strips are clamped into two symmetrically arranged grooves on the outside of the plastic base, and the limiting convex strip is embedded in the limiting strip hole arranged in the center of the bottom of the metal plate.

[0006] Furthermore, the center and one end of the lower side of the metal clamping piece are provided with downwardly facing pins.

[0007] Furthermore, the four corners of the bottom of the plastic base are provided with limited triangular bosses, the four corners of the metal plate are chamfered and the four chamfers are against the inner side surfaces of the four triangular bosses.

[0008] Furthermore, two high limit sleeves and one low limit sleeve are provided at the bottom of the above-mentioned plastic base. The low limit sleeve positions the top limit groove of the through-core capacitor. The high limit sleeve is coaxial with the two step holes for installing the through-core magnetic beads and passes through the positioning hole on the metal plate. The through-core capacitor is a step structure. The positioning hole sleeve on the metal plate is knotted on the through-core capacitor arranged with the big end facing upward. The metal plate rests on two symmetrical steps at the bottom of the plastic base, and the two steps are symmetrically arranged relative to the metal clamping piece.

[0009] A method for manufacturing an anti-interference filter, the method comprising the following steps: Step 1: Capacitor welding: weld the capacitor and the two electrodes of the inverted U shape to the terminals at the bottom of the capacitor; Step 2: Place the three through-core inductors into the three stepped holes of the groove at the top of the plastic base, and insert the electrodes of the capacitors soldered in step 1 into the inner holes of the through-core inductors and the small through holes to ensure that the capacitors are completely placed in the grooves; Step 3: Install the through-core capacitor and the metal plate at the bottom of the plastic base and pass through the electrode, and then use a clamp to fix the metal plate to the bottom of the plastic base; Step 4, the electrode passing through the small through hole is welded to the metal plate to form an electrical connection; Step 5: Use potting glue to fill the groove on the top of the plastic base until the capacitor is covered.

[0010] Furthermore, in the above step 4, the temperature of the soldering iron in the soldering process is 350±10°C, the flux is cleaned after soldering, and the soldering iron is placed in an oven at 125±10°C for 30-40 minutes.

[0011] Furthermore, the capacitor welding process uses a welding tool, which includes a T-shaped seat with a plurality of square cavities arranged on the top. The cross-section of the square cavities is the same as that of the plastic base and a clearance fit is maintained after embedding, and a top column is arranged in the middle.

[0012] Furthermore, the above-mentioned potting process is carried out on a heating plate at 100~120℃, using a needle of 0.6~0.8mm and an air pressure of 4±1 kg / cm². After potting, the product is placed on the heating plate and baked for 4~5 hours. After baking on the heating plate, the product is placed in an oven at 130℃±10℃ and baked for 60 min±10 min to cure.

[0013] Beneficial effects of the present invention: Compared with the prior art, the effects of the present invention are as follows: (1) The structure of the present invention arranges the capacitor on the upper side, the three through-core magnetic beads in the three step holes of the plastic base, and the through-core capacitor at the bottom. Then, the various components are reasonably arranged on the plastic base and the product structure formed by clamping, welding and potting with clamping parts can greatly reduce the interference between the various components. In addition, the capacitor welding four electrodes and the through-core magnetic beads and through-core capacitor components are convenient for installation and arrangement, reducing the difficulty of assembly. (2) The clamping strip structure can realize quick plug-in installation through two clamping strips and a limit convex strip, and the metal plate is tightly attached to the limit step, and the connection is stable and reliable; a grounding pin is set to facilitate connection to a specific circuit board for grounding connection, double-pin plug-in, conductive connection and mechanical connection are more stable; (3) The triangular boss and chamfer are arranged to realize the rapid positioning and installation of the metal plate. The metal plate can be suspended and installed by the triangular boss that is higher than the metal plate, which can avoid mutual interference with the circuit board and ensure the installation stability of the device. (4) A high limit sleeve is set to separate the electrode and the metal plate to achieve electrical insulation isolation. A low limit sleeve is set to position the through-core capacitor, which is convenient for quick installation of the capacitor and ensures that the electrode passes through the through-core capacitor smoothly. A step is set to arrange the metal plate away from one end to make room for the large end of the through-core capacitor. (5) The manufacturing method of anti-interference filter products is optimized to a production process of first welding and then potting. This operation can clean the flux residue inside the product, avoid the risk of poor product performance caused by flux residue inside the product, and effectively solve the problem of performance degradation of anti-interference filter products. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a three-dimensional structural diagram of the anti-interference filter; Figure 2 It is the front structural diagram of the anti-interference filter; Figure 3 yes Figure 2 Schematic diagram of the AA section structure; Figure 4 yes Figure 2 Schematic diagram of the structure of the middle BB section; Figure 5 It is a left-view structural diagram of the anti-interference filter; Figure 6 It is a schematic diagram of the anti-interference filter structure viewed from above; Figure 7 yes Figure 6 Schematic diagram of the CC cross-section structure; Figure 8 This is a schematic diagram of the three-dimensional structure of the anti-interference filter from another perspective (removing the top groove potting glue); Fig. 9 It is a schematic diagram of the three-dimensional structure of the plastic base; Fig.10 It is a three-dimensional structural diagram of the anti-interference filter from another perspective; Fig.11 It is a stereoscopic structural diagram of the electrode layout of the anti-interference filter; Fig.12 It is a schematic diagram of the circuit principle structure of the anti-interference filter; Fig.13 It is a schematic diagram of the metal plate structure from a top view; Fig.14 It is a schematic diagram of the three-dimensional structure of welding tooling. DETAILED DESCRIPTION

[0015] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0016] Example 1: Figure 1-13 As shown, an anti-interference filter includes a plastic base 1, a through-core magnetic bead 2, a capacitor 3, a metal plate 7 and a through-core capacitor 9. A groove 4 is arranged on the top of the plastic base 1, and three step holes 5 and a small through hole 10 are arranged at the bottom of the groove 4. Three through-core magnetic beads 2 are used, which are respectively placed in the three step holes 5. Four electrodes 6 are welded on the bottom of the capacitor 3. The four electrodes 6 pass through the three inner holes and the small through hole 10 of the three through-core magnetic beads 2 respectively, and then the capacitor 3 is close to the top surface of the through-core magnetic bead 2, and the top groove 4 is filled with potting glue. An electrode 6 close to the through-core magnetic bead 2 not installed passes through the plastic base 1 and is sleeved with the through-core capacitor 9. The plastic base 1 The metal plate 7 is clamped and fixed by a metal clamping piece 8 at the bottom, and the through-core capacitor 9 passes through the metal plate 7, and the four electrodes 6 are led out of the metal plate 7, and the electrodes 6 led out of the small through hole 6 are electrically connected to the metal plate 7; in the structure of the present invention, the capacitor is arranged on the upper side, the three through-core magnetic beads are arranged in the three step holes of the plastic base, and the through-core capacitor is arranged at the bottom, and then the various components are reasonably arranged on the plastic base and the product structure formed by clamping welding and potting with a clamping piece can greatly reduce the interference between the various components, and the components of the capacitor welding four electrodes, through-core magnetic beads and through-core capacitors are convenient for installation and arrangement, and reduce the difficulty of assembly.

[0017] In order to simplify the structure of the clamping piece and the connection reliability, the metal clamping piece 8 is a clamping strip structure, and two symmetrical clamping strips 801 facing upward are arranged in the middle of the two ends of the upper side, and a limiting convex strip (802) is arranged in the center. The two clamping strips 801 are clamped into two symmetrically arranged clamping grooves 803 on the outer side of the plastic base 1, and the limiting convex strip 802 is embedded in the limiting strip hole 804 arranged in the center of the bottom of the metal plate 7; the center and one end of the lower side of the metal clamping piece 8 are provided with downward pins 805. The clamping strip structure can realize quick plug-in installation through the two clamping strips and the limiting convex strip, and the metal plate is tightly attached to the limiting step, and the connection is stable and reliable; a grounding pin is arranged to facilitate connection to a specific circuit board for grounding connection, double-pin plug-in, conductive connection and mechanical connection are more stable.

[0018] In order to achieve circumferential limitation of the metal plate, limiting triangular bosses 101 are provided at the four corners of the bottom of the plastic base 1, and the four corners of the metal plate 7 are chamfered and the four chamfers are against the inner sides of the four triangular bosses 101. The triangular bosses and chamfers are arranged in coordination, so that the metal plate can be quickly positioned and installed, and the metal plate can be suspended and installed by the triangular bosses that are higher than the metal plate, which can avoid mutual interference of the circuit boards and ensure the installation stability of the components.

[0019] In order to achieve insulation between the metal plate and the electrode and facilitate docking of the through-core capacitor, two high limit sleeves 102 and a low limit sleeve 103 are arranged at the bottom of the plastic base 1. The low limit sleeve 103 locates the top limit groove of the through-core capacitor 9. The high limit sleeve 102 is coaxial with the two step holes 5 for installing the through-core magnetic beads 2 and passes through the positioning holes on the metal plate 7. The through-core capacitor 9 is a step structure. The positioning hole sleeve on the metal plate 7 is knotted on the through-core capacitor 9 arranged with the big end facing upward. The metal plate 7 rests on two symmetrical steps 104 at the bottom of the plastic base 1, and the two steps 104 are symmetrically arranged relative to the metal clamping piece 8; the high limit sleeve is set to separate the electrode and the metal plate, which can achieve electrical insulation isolation. The low limit sleeve is set to position the through-core capacitor, which is convenient and quick to install the capacitor and ensure that the electrode passes through the through-core capacitor smoothly. The step is set to arrange the metal plate away from one end to make room for the big end of the through-core capacitor.

[0020] Embodiment 2: A method for manufacturing an anti-interference filter, the method comprising the following steps: Step 1: Capacitor welding: weld the capacitor and the two electrodes of the inverted U shape to the terminals at the bottom of the capacitor; Step 2: Place the three through-core inductors into the three stepped holes of the groove at the top of the plastic base, and insert the electrodes of the capacitors soldered in step 1 into the inner holes of the through-core inductors and the small through holes to ensure that the capacitors are completely placed in the grooves; Step 3: Install the through-core capacitor and the metal plate at the bottom of the plastic base and pass through the electrode, and then use a clamp to fix the metal plate to the bottom of the plastic base; Step 4, the electrode passing through the small through hole is welded to the metal plate to form an electrical connection; In step 4, the temperature of the electric soldering iron in the welding process is 350±10℃. After welding, the flux is cleaned and put into the oven after cleaning, and baked at 125±10℃ for 30~40min. In order to facilitate welding, the capacitor welding process adopts welding tooling, such as Fig.14 As shown, the welding tooling includes a T-shaped seat 11, and a plurality of square concave cavities 1101 are arranged on the top of the T-shaped seat 11. The cross section of the square concave cavity 1101 is the same as the cross section of the plastic base 1 and maintains a clearance fit after being embedded. A top column 1102 is arranged in the middle, and the top column can be against the outer side of the inverted capacitor. The soldering tooling is added, and the through-core magnetic beads and the welded capacitor are fixed by relying on the top column and the concave cavity structure. The internal components of the product are not easy to shift or loosen, ensuring that the four electrodes of the capacitor remain stable with the metal plate, which is convenient for welding and fixing; Step 5: Use potting glue to fill the groove on the top of the plastic base until the capacitor is covered; The encapsulation process is carried out on a heating plate at 100~120℃, with a needle of 0.6~0.8mm and an air pressure of 4±1 kg / cm². After encapsulation, the product is placed on the heating plate and baked for 4~5 hours. After baking on the heating plate, the product is placed in an oven at 130℃±10℃ for 60 min±10 min to cure.

[0021] The above description is only a specific implementation mode of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. An anti-interference filter, characterized in that: The invention comprises a plastic base (1), a through-core magnetic bead (2), a capacitor (3), a metal plate (7) and a through-core capacitor (9), wherein a groove (4) is arranged on the top of the plastic base (1), three stepped holes (5) and a small through hole (10) are arranged on the bottom of the groove (4), three through-core magnetic beads (2) are respectively placed in the three stepped holes (5), and four electrodes (6) are welded on the bottom of the capacitor (3), and the four electrodes (6) respectively pass through the three inner holes of the three through-core magnetic beads (2) and the small through hole (10). ) after the capacitor (3) is close to the top surface of the through-core magnetic bead (2), and the top groove (4) is filled with potting glue, an electrode (6) close to the through-core magnetic bead (2) not installed passes through the plastic base (1) and is then sleeved with a through-core capacitor (9), the bottom of the plastic base (1) uses a metal clamping piece (8) to clamp and fix the metal plate (7) and the through-core capacitor (9) passes through the metal plate (7), four electrodes (6) are led out of the metal plate (7), and the electrodes (6) led out of the small through hole (6) are electrically connected to the metal plate (7).

2. An anti-interference filter according to claim 1, characterized in that: The metal clamping member (8) is a clamping strip structure, with two clamping strips (801) symmetrically facing upwards arranged in the middle of the two ends of the upper side, and a limiting convex strip (802) arranged in the center. The two clamping strips (801) are clamped into two symmetrically arranged clamping grooves (803) on the outer side of the plastic base (1), and the limiting convex strip (802) is embedded in a limiting bar-shaped hole (804) arranged in the center of the bottom of the metal plate (7).

3. An anti-interference filter according to claim 1, characterized in that: A downward-facing plug pin (805) is provided at the center and one end of the lower side of the metal clamping piece (8).

4. The anti-interference filter according to claim 1, characterized in that: The four corners of the bottom of the plastic base (1) are provided with limited triangular bosses (101), and the four corners of the metal plate (7) are chamfered, and the four chamfers are against the inner side surfaces of the four triangular bosses (101).

5. The anti-interference filter according to claim 1, characterized in that: Two high limit sleeves (102) and a low limit sleeve (103) are arranged at the bottom of the plastic base (1); the low limit sleeve (103) locates the top limit groove of the through-core capacitor (9); the high limit sleeve (102) is coaxial with two step holes (5) for installing the through-core magnetic beads (2) and passes through the positioning hole on the metal plate (7); the through-core capacitor (9) is a step structure; the positioning hole on the metal plate (7) is sleeved on the through-core capacitor (9) arranged with the large end facing upward; the metal plate (7) abuts against two symmetrical steps (104) at the bottom of the plastic base (1); the two steps (104) are symmetrically arranged relative to the metal clamping piece (8).

6. The method for manufacturing an anti-interference filter according to claim 1, characterized in that: The method comprises the following steps: Step 1: Capacitor welding: weld the capacitor and the two electrodes of the inverted U shape to the terminals at the bottom of the capacitor; Step 2: Place the three through-core inductors into the three stepped holes of the groove at the top of the plastic base, and insert the electrodes of the capacitors soldered in step 1 into the inner holes of the through-core inductors and the small through holes to ensure that the capacitors are completely placed in the grooves; Step 3: Install the through-core capacitor and the metal plate at the bottom of the plastic base and pass through the electrode, and then use a clamp to fix the metal plate to the bottom of the plastic base; Step 4, the electrode passing through the small through hole is welded to the metal plate to form an electrical connection; Step 5: Use potting glue to fill the groove on the top of the plastic base until the capacitor is covered.

7. The method for manufacturing an anti-interference filter according to claim 6, characterized in that: In step 4, the temperature of the soldering iron in the soldering process is 350±10℃. Clean the flux after soldering, put it in the oven after cleaning, and bake it at 125±10℃ for 30~40min.

8. The method for manufacturing an anti-interference filter according to claim 7, characterized in that: The capacitor welding process adopts a welding tool, which comprises a T-shaped seat (11). A plurality of square cavities (1101) are arranged on the top of the T-shaped seat (11). The cross section of the square cavities (1101) is the same as the cross section of the plastic base (1) and a clearance fit is maintained after being embedded. A top column (1102) is arranged in the middle.

9. The method for manufacturing an anti-interference filter according to claim 6, characterized in that: The encapsulation process is carried out on a heating plate at 100~120℃, with a needle of 0.6~0.8mm and an air pressure of 4±1 kg / cm². After encapsulation, the product is placed on the heating plate and baked for 4~5 hours. After baking on the heating plate, the product is placed in an oven at 130℃±10℃ for 60 min±10 min to cure.

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