Noise suppression components

Abstract

To provide a method for manufacturing noise-suppressing components that eliminates or reduces complexity in the molding process involving secondary molding. [Solution] The method for manufacturing the noise suppression component includes: a first placement step in which the magnetic core 20 is placed on the first lower mold 61 such that the corners of the boundary 213 of the magnetic core 20 are supported by the first lower mold 61, and the middle mold 63 is placed on the first lower mold 61, and the magnetic core 20 is received in the receiving portion 631 of the middle mold 63; a first molding step in which the first upper mold 65 is placed on the middle mold 63, and the first resin 40 is filled into the first space 67 formed by the first upper mold 65, the middle mold 63 and the first lower mold 61; a second placement step in which, with the magnetic core 20 held in the first resin 40 in the receiving portion 631 of the middle mold 63, the middle mold 63 is sandwiched between the second upper mold 71 and the second lower mold 73, and the second space 75 is formed by the second upper mold 73, the middle mold 63 and the second lower mold 71; and a second molding step in which the second resin 50 is filled into the second space 75.

Description

Technical Field

[0001] The present invention relates to noise countermeasure components.

Background Art

[0002] Patent Document 1 discloses a noise countermeasure component that can be easily fixed to a lead provided in an electronic component and can prevent the component from falling off the lead after being fixed.

[0003] The noise countermeasure component disclosed in Patent Document 1 includes a magnetic body having a through-hole and an elastomer portion attached to the magnetic body. This noise countermeasure component has a structure in which the magnetic body is disposed inside the elastomer portion.

[0004] The elastomer portion has an introduction path through which a lead of an electronic component is introduced at a position penetrating through the through-hole of the magnetic body. The introduction path is provided with a tapered portion that at least partially narrows the introduction path from one end to the other end.

[0005] When a lead of an electronic component is introduced into the introduction path of the elastomer portion, the elastomer portion elastically deforms and presses against the lead. As a result, the magnetic body is suppressed from slipping down by its own weight along the lead.

[0006] To form the elastomer portion, a mold having a tapered surface is used. The magnetic body is supported in the mold by bringing the magnetic body into contact with the tapered surface of the mold at the boundary between the end surface and the inner peripheral surface of the magnetic body. By molding the raw material composition of the elastomer portion in that state, a noise countermeasure component in which the magnetic body is disposed inside the elastomer portion can be obtained.

Prior Art Documents

Patent Documents

[0007]

Patent Document 1

Summary of the Invention

[0008] As described above, in the noise suppression component described in Patent Document 1, the elastomer portion is molded with the boundary between the end face and the inner circumferential surface of the magnetic material in contact with the tapered portion of the elastomer. Therefore, this noise suppression component has the problem that the boundary between the end face and the inner circumferential surface of the magnetic material is easily exposed from the elastomer portion, and the elastomer portion is prone to peeling off from the magnetic material at this boundary.

[0009] Examples of magnetic materials used in noise suppression components include ferrite (MnZn / NiZn) cores and nanocrystal thin-band wound cores. While these cores exhibit good properties as noise suppression components, they are conductive. When conductive magnetic materials (magnetic cores) are used in noise suppression components, the elastomer portion may peel off, and if the magnetic material breaks and scatters into the surrounding area, it may short-circuit nearby circuits. Furthermore, if the elastomer portion peels off, the grip force on the lead may decrease, potentially causing the mounting position on the lead to change during use. Therefore, in noise suppression components, it is desirable that the magnetic material is not exposed to the outside and that the elastomer portion is resistant to peeling.

[0010] One possible method for completely covering the magnetic material (magnetic core) with an elastomer portion is to perform the molding of the elastomer portion in two stages: primary molding and secondary molding. However, performing the molding process twice is cumbersome. When considering mass production of noise suppression components, it is desirable to eliminate or reduce the complexity of the manufacturing process.

[0011] Therefore, the present invention aims to provide a method for manufacturing noise suppression components that employs a molding process in which secondary molding is performed to completely cover the magnetic core with resin, while also eliminating or reducing complexity as much as possible, taking mass production into consideration.

[0012] Furthermore, the present invention aims to provide a noise suppression component in which the magnetic core is completely covered with resin and the resin is difficult to peel off from the magnetic core. [Means for solving the problem]

[0013] The present invention relates to a method for manufacturing a first noise suppression component, A first arrangement step involves placing the magnetic core on the first lower mold such that the corner of the boundary between the lower end of the magnetic core and the inner circumferential surface is supported by the first lower mold, and placing a plate-shaped medium mold having a receiving portion on the first lower mold, while receiving the magnetic core within the receiving portion of the medium mold; A first molding step involves placing a first upper mold on the aforementioned middle mold and filling the first space formed by the first upper mold, the middle mold, and the first lower mold with a first resin. A second arrangement step in which, with the magnetic core held in the first resin within the receiving portion of the medium-sized mold, the medium-sized mold is sandwiched between a second upper mold and a second lower mold, which are different from the first upper mold and the first lower mold, and a second space is formed between the second upper mold, the medium-sized mold and the second lower mold, A second molding step in which a second resin is filled into the second space, The present invention provides a method for manufacturing noise suppression components equipped with these components.

[0014] Furthermore, the present invention provides a first noise suppression component, A noise suppression component comprising a magnetic core and an outer resin, The magnetic core has a through hole and also has an upper end surface, a lower end surface, an inner circumferential surface and an outer circumferential surface. The aforementioned outer resin completely encloses the magnetic core. An upper parting line and a lower parting line are formed on the outer circumference of the exterior resin, and these lines are spaced apart from each other in the vertical direction. We provide noise suppression components.

[0015] Furthermore, the present invention provides a second noise suppression component, The first noise suppression component, The noise suppression component is attached to the lead of a predetermined component when in use. The outer resin has outer holes corresponding to the through holes of the magnetic core, The minimum diameter of the exterior hole is smaller than the longest size in the cross-section orthogonal to the extending direction of the lead of the predetermined component. Provide a noise countermeasure component.

[0016] Further, the present invention provides, as a third noise countermeasure component, A second noise countermeasure component, In the exterior hole of the exterior resin, a tapered portion whose diameter becomes smaller as it goes from the lower side to the upper side is formed. Provide a noise countermeasure component.

[0017] Further, the present invention provides, as a fourth noise countermeasure component, A first noise countermeasure component, The magnetic core has a first boundary as the boundary between the lower end surface and the outer peripheral surface, and has a second boundary as the boundary between the lower end surface and the inner peripheral surface. The exterior resin has a first resin molded at the time of primary molding and a second resin molded at the time of secondary molding. The first boundary of the magnetic core is covered by the first resin, and the second boundary of the magnetic core is covered by the second resin. Provide a noise countermeasure component.

[0018] Further, the present invention provides, as a fifth noise countermeasure component, A fourth noise countermeasure component, Both the upper end surface and the lower end surface of the first resin are covered by the second resin. The boundary between the first resin and the second resin is located at the outer peripheral portion of the exterior resin. Provide a noise countermeasure component.

[0019] Further, the present invention provides, as a sixth noise countermeasure component, A fifth noise countermeasure component, The upper parting line and the lower parting line are located on the second resin. ]Provide a noise countermeasure component.

[0020] Furthermore, the present invention provides a seventh noise suppression component, The fourth noise suppression component is, The boundary between the first resin and the second resin is located above the upper end surface and below the lower end surface of the magnetic core, respectively. We provide noise suppression components. [Effects of the Invention]

[0021] In a method for manufacturing noise suppression components according to one aspect of the present invention, the mold used in the first molding step is also used in the second molding step. The primary molded product is held within the receiving portion of the mold and can be handled integrally with the mold. When manufacturing multiple noise suppression components simultaneously using a set of molds, multiple primary molded products can be handled integrally with a single mold, thereby eliminating or reducing complexity in a molding process that involves two molding steps. [Brief explanation of the drawing]

[0022] [Figure 1] This is a top perspective view showing a noise suppression component according to a first embodiment of the present invention. The boundary between the first resin and the second resin is indicated by a dashed line. [Figure 2] Figure 1 is a bottom perspective view showing the noise suppression component. The boundary between the first resin and the second resin is indicated by a dashed line. [Figure 3] Figure 1 is a bottom view showing the noise suppression component. The boundary between the first resin and the second resin is indicated by a dashed line. [Figure 4] Figure 3 is a cross-sectional view along line AA showing the noise suppression components. [Figure 5] Figure 3 is a cross-sectional view along line BB showing the noise suppression components. [Figure 6] (a) and (b) are schematic diagrams showing cross-sections perpendicular to the extension direction of the lead. [Figure 7] This figure shows one step in the method for manufacturing noise suppression components. [Figure 8] This diagram shows the next step after the process shown in Figure 7. [Figure 9]This diagram shows the next step after the process shown in Figure 8. [Figure 10] This diagram shows the next step after the process shown in Figure 9. [Figure 11] This figure shows the next step after the process shown in Figure 10. [Figure 12] This figure shows the next step after the process shown in Figure 11. [Figure 13] This diagram shows the next step after the process shown in Figure 12. [Figure 14] This figure shows the next step after the process shown in Figure 13. [Figure 15] This figure shows the next step after the process shown in Figure 14. [Figure 16] This diagram shows the next step after the process shown in Figure 15. [Figure 17] This diagram shows the next step after the process shown in Figure 16. [Figure 18] This diagram shows the next step after the process shown in Figure 17. [Figure 19] This diagram shows the next step after the process shown in Figure 18. [Figure 20] This is a cross-sectional view showing a noise suppression component according to a second embodiment of the present invention. [Figure 21] Figure 20 shows one step in the method for manufacturing noise suppression components. [Figure 22] This figure shows the next step after the process shown in Figure 21. [Modes for carrying out the invention]

[0023] (First Embodiment) Referring to Figures 1 to 3, the noise suppression component 10 according to one embodiment of the present invention has a substantially cylindrical outer shape and an outer casing hole 12 that penetrates its center in the vertical direction. The noise suppression component 10 according to this embodiment is attached to the lead (not shown) of a predetermined component using the outer casing hole 12 when in use. In this embodiment, the vertical direction is the Z direction. The +Z direction is upward, and the -Z direction is downward.

[0024] Referring to Figures 4 and 5, the noise suppression component 10 comprises a magnetic core 20 and an outer resin 30. In this embodiment, the outer resin 30 has a first resin 40 and a second resin 50. As will be described later, the first resin 40 is molded by primary molding (first molding step), and the second resin 50 is molded by secondary molding (second molding step) which is performed after primary molding. Thus, in this embodiment, the outer resin 30 has a first resin 40 molded during primary molding and a second resin 50 molded during secondary molding.

[0025] As can be seen from Figures 3 to 5, the magnetic core 20 has a cylindrical shape. More specifically, the magnetic core 20 has a through hole 22 along a central axis extending in the vertical direction, and also has an upper end surface 201, a lower end surface 203, an inner circumferential surface 205, and an outer circumferential surface 207.

[0026] As shown in Figures 4 and 5, the magnetic core 20 has a first boundary 211 as the boundary between the lower end surface 203 and the outer circumferential surface 207. The magnetic core 20 also has a second boundary 213 as the boundary between the lower end surface 203 and the inner circumferential surface 205. Furthermore, the magnetic core 20 has a third boundary 215 as the boundary between the upper end surface 201 and the outer circumferential surface 207, and a fourth boundary 217 as the boundary between the upper end surface 201 and the inner circumferential surface 205.

[0027] As shown in Figures 4 and 5, the outer resin 30 completely encloses the magnetic core 20. Specifically, the first resin 40 covers the magnetic core 20 from the outer circumference, and the second resin 50 covers the magnetic core 20 from the inner circumference. In particular, the first boundary 211 and the third boundary 215 of the magnetic core 20 are covered by the first resin 40, and the second boundary 213 and the fourth boundary 217 of the magnetic core 20 are covered by the second resin 50. Since the magnetic core 20 is completely enclosed in the outer resin 30, even if the magnetic core 20 is damaged, fragments of the magnetic core 20 will not scatter outside the noise suppression component 10.

[0028] As shown in Figures 4 and 5, in this embodiment, the boundary between the first resin 40 and the second resin 50 is located above the upper end surface 201 and below the lower end surface 203 of the magnetic core 20, respectively. Since the boundary between the first resin 40 and the second resin 50 is far from areas where external forces are likely to act directly, the first resin 40 and the second resin 50 are unlikely to peel off from each other, and are also unlikely to peel off from the magnetic core 20. Areas where external forces are likely to act directly on the outer resin 30 are around the upper end 121 of the outer hole 12 and around the upper and lower ends of the outer circumference, respectively. However, the present invention is not limited thereto. The boundary between the first resin 40 and the second resin 50 can be set arbitrarily.

[0029] As shown in Figures 4 and 5, in this embodiment, the outer casing hole 12 is formed by the second resin 50. The outer casing hole 12 corresponds to the through hole 22 of the magnetic core 20. In other words, the outer casing hole 12 passes inside the through hole 22 of the magnetic core 20. The second resin 50 is elastically deformable and can at least partially enlarge the diameter of the outer casing hole 12.

[0030] As can be seen from Figures 1 and 3, in this embodiment, when viewed along the vertical direction, the shape of the upper end 121 of the outer casing hole 12 is circular. This corresponds to a cross-sectional shape perpendicular to the extending direction of the lead (not shown) of a predetermined component. Also, as can be seen from Figures 2 and 3, in this embodiment, when viewed along the vertical direction, the shape of the lower end 123 of the outer casing hole 12 is racetrack-shaped. However, the present invention is not limited thereto. The shape of the upper end 121 of the outer casing hole 12 does not have to be circular, as long as it corresponds to the cross-sectional shape of the lead. Also, the shape of the lower end 123 of the outer casing hole 12 when viewed along the vertical direction may be circular, elliptical, polygonal, etc.

[0031] As can be seen from Figures 3 to 5, in this embodiment, the cross-sectional area of ​​the upper end 121 of the outer casing hole 12 is smaller than the cross-sectional area of ​​the lower end 123 of the outer casing hole 12. In other words, in this embodiment, the cross-sectional area of ​​the outer casing hole 12 perpendicular to the vertical direction generally decreases from bottom to top. This is to allow for smooth insertion and press-fitting of a lead (not shown) into the outer casing hole 12 during use. To achieve this configuration, the outer casing hole 12 is provided with a tapered portion 125 whose diameter decreases from bottom to top. In this embodiment, the outer casing hole 12 is provided with a plurality of tapered portions 125 (125-1, 125-2, 125-3) with different inclinations. As can be seen from Figures 2 to 5, in a cross-section perpendicular to the vertical direction, the shape of tapered portion 125-1 is circular. Also, in a cross-section perpendicular to the vertical direction, the shape of the upper end of tapered portion 125-2 is circular, and the shape of the lower end is racetrack-shaped. In other words, the cross-sectional shape of the tapered portion 125-2 changes from circular to racetrack-shaped as it moves from the upper end to the lower end. Furthermore, in a cross-section perpendicular to the vertical direction, the shape of the tapered portion 125-3 is racetrack-shaped. The shapes of these tapered portions 125 are designed to accommodate both round-shaped and rectangular-shaped terminals when the terminal connected to the end of the lead is at least partially received within the outer casing hole 12. However, the present invention is not limited thereto. The outer casing hole 12 only needs to have at least one tapered portion 125. Also, in a cross-section perpendicular to the vertical direction, the shapes of all the tapered portions 125 may be similar to each other, for example, circular, rectangular, or racetrack-shaped. Furthermore, in this embodiment, each of the tapered portions 125 is represented by a straight line in a cross-section along the vertical direction, but it may also be represented by a curve.

[0032] The cross-sectional area of ​​the upper end 121 of the outer casing hole 12 is smaller than the cross-sectional area of ​​the lead (not shown) of a given component. In other words, the minimum diameter Dmin (see Figure 3) of the outer casing hole 12 is smaller than the maximum size Slmax (see Figure 6) of the lead of the given component on a cross section perpendicular to the extension direction. In this embodiment, the minimum diameter Dmin of the outer casing hole 12 is the diameter of the upper end 121 of the outer casing hole 12, as shown in Figure 3. The maximum size Slmax of the lead is the diameter of the cross section perpendicular to the extension direction or length direction of the lead if it is circular, as shown in Figure 6, and the major axis if it is elliptical or racetrack shaped. As a result, when the lead is pressed into the outer casing hole 12 during use, the second resin 50 elastically deforms so that the outer casing hole 12 is partially expanded, and the second resin 50 holds the lead by its restoring force. As a result, the noise suppression component 10 is fixed in position relative to the lead, preventing movement relative to the lead or detachment from the lead.

[0033] The noise suppression component 10 is manufactured, for example, as follows. Although the following description explains the manufacturing of one noise suppression component 10, by using a mold that supports the simultaneous manufacturing of multiple noise suppression components 10, it is possible to manufacture multiple noise suppression components 10 simultaneously through the following process. The mold includes a first lower mold 61 (61A), a middle mold 63, a first upper mold 65 (65A), a second lower mold 71 (71A), and a second upper mold 73 (73A).

[0034] First, as shown in Figure 7, a magnetic core 20 is prepared and placed on the first lower mold 61 (first step). This first step is performed so that the first lower mold 61 supports the corner of the boundary between the lower end surface 203 and the inner circumferential surface 205 of the magnetic core 20, i.e., the second boundary 213. In other words, this arrangement is performed so that the first lower mold 61 supports the corner of the magnetic core 20 including the second boundary 213. In this embodiment, the first lower mold 61 partially supports the lower end surface 203 of the core from below in the vertical direction. The first lower mold 61 also supports the inner circumferential surface 205 of the magnetic core 20 in a direction perpendicular to the vertical direction. By supporting the corner of the magnetic core 20 with the first lower mold 61 in this way, the magnetic core 20 can be stably positioned on the first lower mold 61. Conventionally, the magnetic core was supported by an annular line, which meant there was a risk of the magnetic core tilting relative to the lower mold. However, in this embodiment, the magnetic core 20 is supported by a surface, so there is no risk of the magnetic core 20 tilting relative to the first lower mold 61.

[0035] Next, as shown in Figure 8, the medium mold 63 is placed on the first lower mold 61 (second step). The medium mold 63 is plate-shaped and has a predetermined thickness. The medium mold 63 also has a receiving portion 631 that is sized to receive the magnetic core 20. The receiving portion 631 is open at the top and bottom, respectively. In this embodiment, the medium mold 63 has a protruding portion 633 that projects into the receiving portion 631. The protruding portion 633 rises gently inward from the receiving portion 631. By placing the medium mold 63 on the first lower mold 61, the magnetic core 20 is received in the receiving portion 631. Note that this second step may be performed simultaneously with the first step. Alternatively, this second step may be performed before the first step. In any case, the first and second steps constitute the first placement step.

[0036] Next, a first resin material 42 is prepared as shown in Figure 9 (third step). Subsequently, a first upper mold 65 is prepared as shown in Figure 10, and the first upper mold 65 is placed on the middle mold 63 as shown in Figure 11 (fourth step). In the fourth step, a first space 67 is formed by the first upper mold 65, the middle mold 63, and the first lower mold 61. By softening the first resin material 42 while forming the first space 67, the first resin material 42 is filled into the first space 67, and the first resin 40 is formed. Thus, the first molding step is performed in which the first upper mold 65 is placed on the middle mold 63, and the first resin 40 is filled into the first space 67 formed by the first upper mold 65, the middle mold 63, and the first lower mold 61. In the molding of the first resin 40 using the medium mold 63, two parting lines (not shown), namely an upper parting line and a lower parting line, are formed at the mold boundary on the outer surface of the first resin 40. The upper parting line and the lower parting line are located apart from each other in the vertical direction. The vertical distance between the upper parting line and the lower parting line corresponds to the thickness of the medium mold 63. In other words, the presence of these parting lines indicates that the noise suppression component 10 was manufactured using the medium mold 63.

[0037] Next, as shown in Figure 12, the first upper mold 65 is removed from the middle mold 63 (5th step), and then, as shown in Figure 13, the first lower mold 61 is removed from the middle mold 63 (6th step). Steps 5 and 6 may be performed simultaneously.

[0038] As shown in Figure 13, the primary molded product remains inside the receiving portion 631 of the medium mold 63. In other words, the magnetic core 20 remains inside the receiving portion 631, held in place by the first resin 40. The protrusions 633 of the medium mold 63 help to hold the primary molded product inside the receiving portion 631.

[0039] Next, as shown in Figure 14, the medium mold 63 is placed on the second lower mold 71 together with the magnetic core 20 and the first resin 40 (step 7). The second lower mold 71 is a different mold from the first lower mold 61. By using the medium mold 63, the primary molded product can be aligned accurately and easily with respect to the second lower mold 71.

[0040] Next, as shown in Figure 15, the second upper mold 73 is placed on the middle mold 63 (step 8). The second upper mold 73 is a different mold from the first upper mold 65.

[0041] In the seventh and eighth steps described above, the medium mold 63 is sandwiched between the second upper mold 73 and the second lower mold 71 while the magnetic core 20 is held in the first resin 40 within the receiving portion 631 of the medium mold 63. The seventh and eighth steps constitute the second placement step, thereby forming a second space 75 between the second upper mold 73, the medium mold 63, and the second lower mold 71. In this embodiment, the second resin material 52 is set in the second upper mold 73.

[0042] Next, as can be seen from Figures 16 and 17, the second resin material 52 is melted and the second resin 50 is filled into the second space 75 using the plunger 77 (step 9). This step 9 constitutes the second molding step.

[0043] Next, as shown in Figure 18, the second upper mold 73 is removed from the middle mold 63, and then the second lower mold 71 is removed from the middle mold 63 (step 10). This yields a secondary molded product held in the middle mold 63, i.e., the noise suppression component 10, as shown in Figure 19. Finally, the secondary molded product is removed from the middle mold 63 (step 11). The first resin 40 is elastically deformable and can be removed from the middle mold 63 regardless of the presence of the protrusions 633. In this way, the noise suppression component 10 shown in Figures 1 and 2 can be obtained.

[0044] As described above, in the manufacturing of the noise suppression component 10 according to this embodiment, the intermediate mold 63 is used in common in the first molding step and the second molding step. Since the primary molded product can be held in the intermediate mold 63 and the process can proceed to the secondary molding step, there is no need to remove the primary molded product from the intermediate mold 63 and set it in the secondary mold (second lower mold 71 and second upper mold 73). In addition, aligning the intermediate mold 63 with the secondary mold is easier than when setting the primary molded product in the secondary mold. Therefore, the handling of the primary molded product is easy, and the manufacturing process does not become complicated even if molding is performed twice. In particular, when manufacturing multiple noise suppression components 10 simultaneously, multiple primary molded products can be handled together, so high manufacturing efficiency can be expected. In addition, by using the intermediate mold 63, sufficient thickness can be given to the outer resin 30 or the second resin 50 around the corner of the second boundary 213 that was supported by the first lower mold 61, making it difficult for the outer resin 30 to peel off.

[0045] (Second Embodiment) Referring to Figure 20, the noise suppression component 10A according to the second embodiment comprises a magnetic core 20 and an outer resin 30A. The outer resin 30A has a first resin 40A and a second resin 50A. The basic configuration of the noise suppression component 10A is the same as the basic configuration of the noise suppression component 10 of the first embodiment. The difference between the noise suppression component 10A and the noise suppression component 10 lies in the shape of the first resin 40A and the second resin 50A.

[0046] As shown in Figure 20, in this embodiment, both the upper end surface 401 and the lower end surface 403 of the first resin 40A are covered by the second resin 50A. In this embodiment, the boundary between the first resin 40A and the second resin 50A that is exposed to the outside is located on the outer periphery of the outer resin 30A. The contact area between the second resin 50A and the first resin 40A is wider than that of the noise suppression component 10 according to the first embodiment. With this configuration, the second resin 50A is less likely to peel off from the first resin 40A.

[0047] The noise suppression component 10A can be manufactured using the same process as the noise suppression component 10 in the first embodiment. However, the molds used to manufacture the noise suppression component 10A differ in shape from those used to manufacture the noise suppression component 10, except for the medium mold 63.

[0048] Referring to Figure 21, the first molding step in this embodiment is performed using a first lower mold 61A, a middle mold 63, and a first upper mold 65A. In this embodiment, the upper end surface 401 of the first resin 40A is located below the upper surface 641 of the middle mold 63 in the vertical direction. Also, the lower end surface 403 of the first resin 40A is located above the lower surface 643 of the middle mold 63 in the vertical direction. This is to ensure that the location of burrs that may occur in the first molding step is different from the location of burrs that may occur in the second molding step. However, the present invention is not limited thereto. The upper end surface 401 of the first resin 40A may be located at the same position as the upper surface 641 of the middle mold 63 in the vertical direction. Also, the lower end surface 403 of the first resin 40A may be located at the same position as the lower surface 643 of the middle mold 63 in the vertical direction.

[0049] Referring to Figure 22, the second molding step in this embodiment is performed using a second lower mold 71A, a second upper mold 73A, and an intermediate mold 63 that holds the primary molded product. The parting line surface, which is the boundary between the second lower mold 71A and the intermediate mold 63, is located below the lower end surface 403 of the first resin 40A in the vertical direction. Also, the parting line surface, which is the boundary between the second upper mold 73A and the intermediate mold 63, is located above the upper end surface 401 of the first resin 40A in the vertical direction. The parting lines formed by the second molding step are formed on the outer circumference of the second resin 50A. Specifically, an upper parting line and a lower parting line are formed on the outer circumference of the second resin 50A, which are located apart from each other in the vertical direction. The presence of these parting lines indicates that the noise suppression component 10A was manufactured using the intermediate mold 63.

[0050] As described above, the manufacturing method for the noise suppression components 10 and 10A according to this embodiment involves two molding steps, but by using the medium mold 63, the complexity of these steps is eliminated or reduced, making it easy to manufacture the noise suppression components 10 or 10A. Moreover, this method is suitable for mass production. In addition, in the noise suppression components 10 or 10A manufactured by this method, the outer resin 30 or 30A completely encloses the magnetic core 20 and is difficult to peel off. Therefore, even if the magnetic core 20 is damaged, it will not scatter into the surroundings. Furthermore, the noise suppression components 10 and 10A can have sufficient holding force against the leads.

[0051] Although the present invention has been described above with reference to several embodiments, the present invention is not limited to the above embodiments, and various modifications and changes are possible without departing from the spirit of the present invention. For example, in the above embodiments, the first molding step is performed by a compression method and the second molding step is performed by an injection method, but the present invention is not limited to this. The first molding step may be performed by a transfer method, or the second molding step may be performed by a compression method. Furthermore, the first molding step and the second molding step may be performed by the same method. [Explanation of Symbols]

[0052] 10, 10A Noise suppression components 12 Exterior hole 121 Upper end 123 Bottom end 125 Tapered section 20 magnetic cores 201 Upper end surface 203 Lower end surface 205 Inner surface 207 Outer surface 211 1st boundary 213 Second boundary 215 Third boundary 217 Fourth Boundary 22 Through hole 30, 30A Outer resin 40, 40A First resin 401 Upper end surface 403 Lower end surface 42. First Resin Material 50, 50A Second resin 52. Second Resin Material 61, 61A 1st lower mold 63 medium size 631 Receptor part 633 Projection part 641 Top surface 643 Bottom surface 65, 65A 1st upper mold 67 1st space 71, 71A 2nd lower mold 73, 73A 2nd upper mold 75 Second space 77 Plungers

Claims

1. A first arrangement step involves placing the magnetic core on the first lower mold such that the corner of the boundary between the lower end surface and the inner circumferential surface of the magnetic core is supported by the first lower mold, and placing a plate-shaped medium mold having a receiving portion on the first lower mold, while receiving the magnetic core within the receiving portion of the medium mold, A first molding step involves placing a first upper mold on the aforementioned middle mold and filling the first space formed by the first upper mold, the middle mold, and the first lower mold with a first resin. A second arrangement step in which, with the magnetic core held in the first resin within the receiving portion of the medium-sized mold, the medium-sized mold is sandwiched between a second upper mold and a second lower mold, which are different from the first upper mold and the first lower mold, and a second space is formed between the second upper mold, the medium-sized mold and the second lower mold, A second molding step of filling the second space with a second resin, A method for manufacturing noise suppression components.

2. A noise suppression component comprising a magnetic core and an outer resin, The magnetic core has a through hole and also has an upper end surface, a lower end surface, an inner circumferential surface and an outer circumferential surface. The aforementioned outer resin completely encloses the magnetic core. An upper parting line and a lower parting line are formed on the outer circumference of the exterior resin, and these lines are spaced apart from each other in the vertical direction. Noise suppression component.

3. A noise suppression component according to claim 2, The noise suppression component is attached to the lead of a predetermined component when in use. The outer resin has outer holes corresponding to the through holes of the magnetic core, The minimum diameter of the exterior hole is smaller than the longest size on the cross-section perpendicular to the extending direction of the lead of the predetermined component. Noise suppression component.

4. A noise suppression component according to claim 3, The outer pores of the outer resin have tapered sections formed in them, with the diameter decreasing from bottom to top. Noise suppression component.

5. A noise suppression component according to claim 2, The magnetic core has a first boundary as the boundary between the lower end surface and the outer circumferential surface, and a second boundary as the boundary between the lower end surface and the inner circumferential surface. The exterior resin comprises a first resin molded during primary molding and a second resin molded during secondary molding. The first boundary of the magnetic core is covered with the first resin, and the second boundary of the magnetic core is covered with the second resin. Noise suppression component.

6. A noise suppression component according to claim 5, Both the upper and lower end surfaces of the first resin are covered with the second resin. The boundary between the first resin and the second resin is located on the outer periphery of the exterior resin. Noise suppression component.

7. A noise suppression component according to claim 6, The upper parting line and the lower parting line are located on the second resin. Noise suppression component.

8. A noise suppression component according to claim 5, The boundary between the first resin and the second resin is located above the upper end surface and below the lower end surface of the magnetic core, respectively. Noise suppression component.

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