Inductive component, molding die and embedding method

Abstract

The present invention provides an inductive component that is easy to manufacture and has precisely adjustable electrical and magnetic properties. The inductive component has a body including a central region of an electrical conductor. The central region is located at the center of the body. Furthermore, the body has one or more recessed grooves that open outward.

Description

[Technical Field]

[0001] The present invention relates to inductive components, and in particular to inductive components with improved magnetic properties, to forming tools for producing such components, and to embedding methods for embedding, for example, electrical conductors into the body of the component. [Background technology]

[0002] Inductive components can be applied to circuits where an inductive switching element is realized by the inductive component. Generally, the inductance of such components is characterized by the shape of the electrical conductor and the magnetic properties of its surrounding environment. This allows the coil to be cast with a surrounding material. The position of the coil in the casting material affects the magnetic and electrical properties of the corresponding component.

[0003] For example, US Patent No. 9,728,331, US Patent No. 4,801,912 or US Patent Application Publication No. 2010 / 0219924 disclose inductive elements with a holder for a coil, while US Patent Application Publication No. 2012 / 0019343 or US Patent Application Publication No. 2009 / 0250836 disclose complex method steps for manufacturing inductive components.

[0004] However, there remains a need for inductive components that can be fabricated using simple and easy-to-implement manufacturing processes, have precisely adjustable magnetic properties, and have precisely positioned and precisely aligned contact terminals for connection with an external circuit environment. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] U.S. Patent No. 9,728,331 [Patent Document 2] U.S. Patent No. 4,801,912 [Patent Document 3] US Patent Application Publication No. 2010 / 0219924 [Patent Document 4] US Patent Application Publication No. 2012 / 0019343 [Patent Document 5] US Patent Application Publication No. 2009 / 0250836 Summary of the Invention

[0006] To this end, an inductive component or a mould and a method for embedding an electrical conductor are provided according to the independent claims. The dependent claims provide advantageous technical solutions.

[0007] The inductive component includes an electrical conductor. The electrical conductor has a first terminal and a second terminal. The electrical conductor further has a central region. The central region is electrically disposed between the first terminal and the second terminal. The inductive component further has a body, the central region being disposed within the body. The central region is disposed at the center of the body. Furthermore, the body has a first recess that opens outward.

[0008] "The central region is electrically disposed between the first terminal and the second terminal" essentially means that the electrical conductor is configured such that the central region of the electrical conductor is connected in series between the first terminal and the second terminal. Because the central region is provided at the center of the body, the position of the central region on the body can be defined with high precision. In this way, the magnetic environment of the central region of the electrical conductor can be defined with high precision, and the electrical and magnetic properties of the inductive element can be adjusted with high precision.

[0009] The presence of the outward-opening grooves directly leads to highly adjustable inductance. Therefore, the outward-opening grooves are used to hold the electrical conductor, and in particular its central region, in a predetermined position during the manufacturing process of the inductive component. In this case, the molding material can surround the central region, ensuring reliable fixation of the central region even under high molding pressure. Therefore, the position within the body and the thickness of the body material in each direction surrounding the central region are fixedly defined, thus enabling the electrical and magnetic properties of the inductive component to be adjusted with high precision.

[0010] The central region of the electrical conductor is essentially the region of the conductor that largely determines the electrical or magnetic properties of the inductive component.

[0011] One or more grooves may form an angle β with the corresponding side surface, where 0°≦β≦20°. Here, the corresponding side surface is the side surface that contains the corresponding groove. An angle >0° means that the groove, and in particular its side surface, is inclined laterally. In this way, the central region (especially when two grooves are provided opposite each other) can be fixed and thus pressed downward, thereby optimally aligning one side of the terminal for subsequent soldering and aligning the central region with the body material. Therefore, the corresponding molding tool can have a V-shaped region that opens downward. That is, the opening of the "V" faces downward.

[0012] The electrical conductor may be formed with one or more coils in the central region, and may be comprised of one or more wires, or may include a single wire with corresponding portions being windings that form the coils of the inductive component.

[0013] The first and second terminals of the electrical conductor are connection means of the inductive component for connecting the inductive component to the external circuit environment. The first and second terminals can protrude from the body of the inductive component on different sides of the component. However, the two terminals can also protrude from the same side of the body. This is particularly advantageous when the inductive component has to be connected to a printed circuit board using SMD technology (SMD = surface mounted device).

[0014] The coil may have substantially circular windings. The coil may in particular be a cylindrical coil or a planar coil. However, the windings of the coil may also follow an elliptical or rectangular cross section.

[0015] The body in which the central region of the inductive element is provided may comprise or consist of a molding material.

[0016] Alternatively, the central region of the electrical conductor may be embedded in the body of the inductive component.

[0017] Embedding by molding (casting) is an easy method of manufacturing inductive components. The central region can be integrally formed with the surrounding molding material. The central region of the electrical conductor is generally in contact with the molding material over its entire length.

[0018] The main body may have a second groove that opens outward, and the second groove may be provided on the main body opposite the first groove such that a central region is provided between the first groove and the second groove.

[0019] The significance of these grooves is that during production, the corresponding molding tool has correspondingly shaped elements, such as ribs or fins, which hold the central area of ​​the inductor in a predetermined position during molding. During molding, i.e. during casting with a molding compound, even if a high molding pressure is required for some molding compounds, the ribs of the molding tool can press the central area of ​​the electrical conductor from different directions (e.g. opposite directions) and hold this central area in a fixed position with high precision.

[0020] In particular, the molding die has a cavity that is designed to be filled with a molding material that forms a subsequent body that integrally encapsulates the electrical conductor and its central region.

[0021] In addition to the limitations of the molding die cavity, the highly precisely defined positioning of the central region allows for precise adjustment of the external dimensions, and by determining the central region of the electrical conductor with high precision, an inductive component is realized in which the electrical conductor, and in particular the magnetic environment of the central region, is determined with high precision.

[0022] Thus, the electrical and magnetic properties of the inductive component can be adjusted with high precision, resulting in an inductive component with precise electrical and magnetic properties, which can be manufactured using easy-to-implement method steps.

[0023] The induction component may further include a first groove located on the main body.

[0024] The number of grooves in the body, i.e., the number of positions or directions that can be used to fix the central region of the electrical conductor during casting, determines the adjustment accuracy of the central region and determines the mechanical resistance that the central region can provide during the casting of the casting material.

[0025] However, in the grooves, the corresponding conductor portions of the electrical conductors contain relatively little molding material around them, and such grooves can be regarded as non-uniformities in the magnetic environment of the inductive component. Therefore, a specific inductive component generally has a specific number and specific positions of grooves, so that the advantageous properties of the grooves can cover the lack of corresponding material.

[0026] Ideally, the depth and width of the recessed grooves are selected to provide sufficient mechanical stability for the positioning of the central region and sufficient low interference from the magnetic environment.

[0027] Accordingly, the induction element may further include a second groove located on the main body, the first groove and the second groove being substantially on opposite sides of the induction element.

[0028] Due to the opposing arrangement of the recesses or the opposing arrangement of the corresponding ribs in the molding tool, the central area is optimally clamped during production, thereby enabling optimal fixation of the central area during the injection of the molding compound.

[0029] In one embodiment, one or more or all of the grooves have a height h in the longitudinal direction y, where 0.8*H≦h, and H is the height of the body. The height H of the body may be 1 mm to 10 mm.

[0030] In one embodiment, one or more or all of the grooves have a width b, where 0.1*L≦b≦0.9*L, where L is the length of the body.

[0031] In one embodiment, one or more or all of the grooves have a depth t, where 0.01*L≦t≦0.5*L, where L is the length of the body.

[0032] The width b of the recessed groove may satisfy the condition 0.1 mm≦b≦3.0 mm.

[0033] Accordingly, the depth t of the recessed groove may satisfy 0.05 mm≦t≦1.0 mm.

[0034] The body of the induction component may have a generally cubic shape, with side lengths K1, K2, K3 that may be between 0.2 mm and 10 mm.

[0035] The shape of the body corresponds exactly to a cube, with the exception of the terminals. However, it is usually advantageous for the exact shape of the body to differ slightly from a cube, so that the edges of the cube may each have a chamfered surface, for example. The body may also have asymmetrical sides relative to the other sides of the body, for example to simplify the orientation of the component during connection to a printed circuit board.

[0036] The body may have, at its top surface, two angled chamfered surfaces extending longitudinally on lateral sides of the top surface.

[0037] The body may have one or two end faces, each having six edges.

[0038] The body may have two sides facing each other in the lateral direction x and making an angle α with respect to each other, where 0°<α≦20°.

[0039] The first terminal and the second terminal may provide an externally accessible flat surface.

[0040] The flat surface may be suitable for making a solder connection.

[0041] Accordingly, the inductive element may be an SMD element.

[0042] Thus, the terminals of the inductive component can protrude from the body of the component a length suitable for mechanically and electrically connecting the body to conductive structures on a printed circuit board, and in particular, the surfaces of the terminals can be wetted with a solderable material.

[0043] The electrical conductor may have an inductance I that may be greater than or equal to 5 nH and less than or equal to 470 μH.

[0044] The inductive element may have a top surface and an opposing bottom surface. The component may have four grooves located on the top surface and two grooves located on the bottom surface. In particular, the four grooves on the top surface may be provided on each side of a substantially rectangular base surface.

[0045] Correspondingly, the two recessed grooves in the bottom surface are preferably provided on opposite sides of the generally cubic body.

[0046] The body may have a magnetic permeability P of 1.5 H / m or more and 100 H / m or less.

[0047] The body of the inductive component may comprise a plastic filled with a magnetic material.

[0048] Materials such as ferrites and iron alloys for magnetic materials mixed as fillers in a plastic matrix can be used as materials for the plastic and for magnetic filling.

[0049] When the body comprises a molding material, the molding material may comprise or consist of a synthetic resin such as an epoxy resin.

[0050] The electrical conductor may comprise or consist of one material selected from copper (Cu), silver (Ag), gold (Au) and aluminum (Al).

[0051] The recessed groove may have a base surface that is generally rectangular, square, circular, trapezoidal or elliptical.

[0052] The base surface of the recessed groove may include or consist of a flat surface.

[0053] A corresponding mould for manufacturing the induction component may include an inlet and ribs.

[0054] The inlet is used as an opening for adding molding material during the manufacturing process, and the rib is used as a support member to precisely secure the central area of ​​the electrical conductor in a predetermined position in the finished part.

[0055] The mold may have a bottom and a top. The bottom may have two ribs and the top four ribs, or vice versa. The ribs hold the center region in place during casting and then appear as grooves in the finished molded part.

[0056] The mold may further have side walls with a cavity in which the central region of the conductor can be placed, the side walls defining the subsequent outer surface of the part.

[0057] The method of embedding the central region of the electrical conductor at the center is as follows: providing a molding die having an inlet and ribs; Providing an electrical conductor; positioning a central region on the rib; and encapsulating the central region by extruding molding material through the inlet.

[0058] Using the mold, the method steps result in an inductive component having a highly centered central region of electrical conductor and a precisely defined material thickness on the sidewalls between the central region and the outer surface of the body, thus providing an inductive component that is easily manufactured and has precisely defined electrical and magnetic properties. [Brief explanation of the drawings]

[0059] The functional principles and details of preferred embodiments are explained in detail with reference to the schematic drawings.

[0060] [Figure 1] FIG. 1 is a perspective view of an inductive component. [Figure 2] FIG. 2 is a perspective view of an inductive element having two chamfered surfaces located on the top surface. [Figure 3] FIG. 3 is a perspective view of the bottom of the part. [Figure 4] FIG. 4 shows the body of the inductive component in cross section so that the location and orientation of the electrical conductors can be visualized. [Figure 5] FIG. 5 is a perspective view of the central region where the coil is formed. [Figure 6] FIG. 6 is a perspective view of a molding tool having an inlet for applying molding material. [Figure 7] FIG. 7 is a cross-sectional view of the mold and molding material arrangement giving the dimensions of the preferred embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0061] FIG. 1 is a perspective view of an inductive component IB having a body K, a first terminal AN1, and a second terminal AN2. The body K has a generally cubic shape and a top surface O. The body K further has a side surface SF. A groove AU is provided on or within the side surface SF. The base surface of the groove AU is inclined relative to the longitudinal direction y or the side surface SF, so that a rib R of the molding die can apply a force component in the downward direction (y direction) to this base surface, thereby fixing the central region of the electrical conductor to the substrate and molding material. As can be seen from this perspective view, the terminals AN1 and AN2 are provided on the bottom surface. These terminals can be used, for example, for SMD mounting.

[0062] 2 is a perspective view of an induction component OB having a body K. The roughly cubic body K has two chamfered surfaces F at the edge located on its top surface O. These chamfered surfaces reduce burrs and simplify subsequent installation.

[0063] The recessed groove has a substantially trapezoidal base surface with the ridges at the top surface longer than the ridges at the bottom surface.

[0064] The groove is particularly shaped to allow the rib (which may be better called a fin or punch, depending on its width) of the molding die to come into direct contact with at least a portion of the top surface of the first terminal AN1, thereby allowing the terminal to be more effectively pressed against the base of the molding die by applying force, thereby fixing the terminal and the central region together.

[0065] Figure 3 is a perspective view of an induction component IB with its base U facing the viewer. As can be seen from Figure 3, the generally cubic body K has an orientation plane OF rather than an edge, which simplifies the orientation and alignment of the component IB by breaking the symmetry.

[0066] 4 is a perspective view of the inductive element IB showing a cross section of the body K. Thus, the position of the electrical conductors within the body K can be seen.

[0067] 5 is a perspective view of an electrical conductor EL, the central region ZB of which contains the windings of a coil electrically connected in series between a first terminal AN1 and a second terminal AN2. The terminals AN1 and AN2 are used to connect the inductive component to an external circuit environment. The shape of the conductor EL in the central region ZB substantially determines the electrical and magnetic properties of the inductive component.

[0068] Here, the electrical conductor itself is formed from a strip having a constant width and thickness, the thickness being smaller than the width.

[0069] The windings of the coil are insulated from one another by the common dielectric material of the body K.

[0070] 6 is a perspective view of a molding die MW having an inlet Z configured as a hole through which the potting material can be forced into the cavity behind the inlet with an appropriate pressure to completely fill the cavity without pushing the central region of the electrical conductor out of its preferred position.

[0071] Figure 7 shows a cross-sectional view of the rib R during molding. During sealing, the rib R holds the central region in place, preventing the molding material from occupying the volume of the rib R, allowing the groove to later be positioned at the rib's location. [Explanation of symbols]

[0072] AN, AN1, AN2 terminal, 1st terminal, 2nd terminal AU groove, recess b, h, t Width, height, depth of groove B, H, L Width, height, length of the main body EL Electrical Conductor F Chamfered surface IB Inductive Components K main unit O Top surface OF orientation plane R Rib, Fin, Punch SP coil U Bottom MW molding die ZB center area Z entrance

Claims

1. an electrical conductor (EL) having a first terminal (A1), a second terminal (A2), and a central region (ZB) electrically disposed between the first terminal and the second terminal; a body (K) in which the central region is provided, The central region is provided at the center of the body, The body has one or more first grooves (A) opening outward, an induction element (IB).

2. The inductive component according to claim 1 , wherein each of the one or more grooves forms an angle β with a corresponding side surface, where 0°≦β≦20°.

3. 10. An inductive component according to any one of the preceding claims, wherein the conductor is formed with one or more coils (SP) in the central region.

4. 10. An inductive component according to the preceding claim, wherein the body comprises or consists of a moulded material.

5. 10. An inductive component according to any one of the preceding claims, wherein the central region is embedded in the body.

6. The induction component according to any one of the above claims, wherein the main body includes one or more second grooves that open outward, and the second grooves are provided on the main body opposite the first grooves so that the central region is provided between the first groove and the second groove.

7. The inductive component of any one of the preceding claims, further comprising a further first groove located on the body.

8. The inductive component according to any one of the preceding claims, further comprising a second groove located on the body, the first groove and the second groove being provided on opposite sides of the body.

9. 10. An inductive component according to any one of the preceding claims, wherein one or more or all of the grooves have a height h in the longitudinal direction y, where 0.8*H≦h, and H is the height of the body.

10. 10. An inductive component according to any one of the preceding claims, wherein one or more or all of the grooves have a width b, where 0.1*L≦b≦0.9*L, and L is the length of the body.

11. 10. An inductive component according to any one of the preceding claims, wherein one or more or all of the grooves have a depth t, where 0.01*L≦t≦0.5*L, where L is the length of the body.

12. The induction component according to claim 1 , wherein a width b of the recessed groove satisfies 0.1 mm≦b≦3.0 mm.

13. The induction component according to claim 1 , wherein the depth t of the recessed groove satisfies 0.05 mm≦t≦3.0 mm.

14. 10. The inductive component according to claim 1, wherein the body has a substantially cubic shape with side lengths K1, K2, K3, where 0.2 mm≦K1, K2, K3≦10 mm.

15. 10. An inductive component according to any one of the preceding claims, wherein the body has, at its top surface, two inclined chamfered surfaces extending longitudinally on lateral sides of the top surface.

16. 10. An inductive component according to any one of the preceding claims, wherein the body has one or two end faces, each end face having six edges.

17. 10. An inductive component according to any one of the preceding claims, wherein the body has two sides facing each other in the transverse direction x and making an angle α with respect to each other, where 0°<α≦20°.

18. 10. An inductive component according to any one of the preceding claims, wherein the first terminal and the second terminal present an externally accessible flat surface.

19. 10. An inductive component according to the preceding claim, wherein said flat surface is suitable for soldering.

20. 10. An inductive component according to any one of the preceding claims, wherein the inductive component is an SMD element.

21. 10. An inductive component according to any one of the preceding claims, wherein the electrical conductor has an inductance I, where 5nH≦I≦470μH.

22. 10. The inductive component of claim 1, having a top surface, an opposing bottom surface, one, two, three or four grooves located on the top surface, and one, two, three or four grooves located on the bottom surface.

23. 10. The inductive component according to any one of the preceding claims, wherein the body has a magnetic permeability P, where 1.5 H / m≦P≦100 H / m.

24. 10. An inductive component according to any one of the preceding claims, wherein the body comprises plastic filled with magnetic material.

25. 10. An inductive component according to any one of the preceding claims, wherein the electrical conductor comprises or consists of one material selected from Cu, Ag, Au, Al.

26. A mould for manufacturing an induction component according to any one of the preceding claims, comprising an inlet (Z) and a rib (R).

27. 10. The molding tool of claim 9, comprising a lower portion, an upper portion, one, two, three or four ribs located on the lower portion, and one, two, three or four ribs located on the upper portion.

28. providing a molding die having an inlet and ribs; Providing an electrical conductor; positioning a central region on the rib; and encapsulating said central region by extruding a molding material through said inlet.

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