CN106716563A - Novel structure of double gap sensor - Google Patents

Abstract

A low loss power inductor core and method for making same. The magnetic core includes an outer portion formed as a closed loop from multiple magnetic core pieces, and inner portion disposed within the closed loop. Non-magnetic spacers at opposing ends of the inner core portion position and secure the inner core portion between mutually opposed inner sides of the closed loop.

Description

Novel structure of double gap sensor

technical field

The present invention relates to inductors, and in particular to inductors for storing energy in high power applications.

Background technique

Prior patent applications (US Patent Application 61/782457, filed March 14, 2013 and entitled "Low loss inductor windings using offset gap, offset windings," and filed March 12, 2014 and entitled "Low Loss US Patent Application 14/206511 to Inductor With Offset Gap and Windings", the entire contents of both documents are hereby incorporated by reference) describes a novel method of wrapping a conductive foil around a magnetic core assembly. The assembly employs a common embodiment in which the magnetic core has a controlled size non-magnetic gap between one end of the central core finger (or central leg) and the adjacent magnetic member. A refinement of this assembly is to suspend the magnetic core so that each end of the core has a non-magnetic gap of controlled size between that end and the surrounding magnetic material. This application describes a mechanical support for such a double non-magnetic gap core.

Contents of the invention

According to the invention claimed in the present application, there are provided a low loss power inductor core and a method for manufacturing the low loss power inductor core. The magnetic core includes an outer portion formed as a closed loop by a plurality of magnetic core pieces and an inner portion arranged within the closed loop. Non-magnetic spacers at opposing ends of the inner core portion locate and secure the inner core portion between mutually opposed inner sides of the closed loop.

According to one embodiment of the presently claimed invention, a low loss power inductor core comprises: an outer magnetic core portion comprising a plurality of magnetic core pieces arranged to form a closed loop; an inner magnetic core portion arranged in within the closed loop and comprising mutually opposed first and second ends separated by a 1-shaped magnetic core piece; a first non-magnetic spacer disposed between the first end and the first inner side of the closed loop; and disposed at the second end and a second non-magnetic spacer between the second inner side of the closed loop.

According to another embodiment of the invention claimed in the present application, the low loss power inductor core comprises: using a plurality of magnetic core pieces to form a closed loop as the outer magnetic core part; A 1-shaped magnetic core piece is positioned within the closed loop as an inner magnetic core portion; a first non-magnetic spacer is positioned between the first end and the first inner side of the closed loop; a second non-magnetic spacer is positioned at the second end and the second inner side of the closed loop.

Description of drawings

1A-1D depict an inductor core according to an exemplary embodiment of the presently claimed invention.

Figure 2 depicts an alternative view of the core of Figure IB.

Figure 3 depicts an exemplary copper foil and insulator for wrapping around a core.

4A-4B depict spacers used in assembling an inductor core according to an exemplary embodiment of the presently claimed invention.

5A-5D depict alternative spacers for use in assembling an inductor core according to an exemplary embodiment of the presently claimed invention.

detailed description

Exemplary embodiments of the invention claimed in the present application are described in detail below with reference to the accompanying drawings. These descriptions are intended to be illustrative, not limiting, of the scope of the invention. These embodiments have been described in sufficient detail to enable those skilled in the art to practice the subject invention, it being understood that other embodiments may be practiced with some modification without departing from the spirit or scope of the subject invention.

Figure 1(a) shows a cross-section of an assembly consisting of two 'U'-shaped pieces (111, 112) made of magnetic material connected ) leaving an inflated volume. In the air-filled volume (113) in the central part of the assembly, it is desirable to place another core (114) of magnetic material so that it is suspended in the central part and separated from the other two pieces of magnetic material. A non-magnetic gap (115, 116) is formed, which is a carefully controlled distance. A precisely controlled nonmagnetic gap (115, 116) is important for optimal performance of the magnetic assembly.

Figure 1(b) shows a cross-section of an alternative construction assembly consisting of a 'U'-shaped piece (101) and an 'I'-shaped piece (102) made of magnetic material, the 'U'-shaped piece and the 'I'-shaped piece connected together while leaving an air-filled volume in the central part (103). In the air-filled volume (103) in the central part of the assembly, it is desirable to place another core (104) of magnetic material so that it is suspended in the central part and forms a Non-magnetic gaps (105, 106), which are carefully controlled distances. A precisely controlled nonmagnetic gap (105, 106) is important for optimal performance of the magnetic assembly.

Figure 1(c) shows a cross-section of an alternative construction assembly made of shaped pieces (121, 122, 123, 124) made of magnetic material joined together while leaving a gap in the central part (130). Lower inflated volume. In the air-filled volume (130) in the central part of the assembly, it is desirable to place a further core (124) of magnetic material so that it is suspended in the central part and connected to other pieces of magnetic material ( 121, 122) form a non-magnetic gap (125, 126), which is a carefully controlled distance. A precisely controlled non-magnetic gap (125, 126) is important for optimal performance of the magnetic assembly.

Figure 1(d) shows a cross-section of an alternative construction assembly consisting of two 'L'-shaped pieces (131, 132) made of magnetic material joined together with a central An inflated volume remains in section (133). In the air-filled volume (133) in the central part of the assembly, it is desirable to place another core (134) of magnetic material so that it is suspended in the central part and separated from the other two pieces of magnetic material. A non-magnetic gap (135, 136) is formed, which is a carefully controlled distance. A precisely controlled non-magnetic gap (135, 136) is important for optimal performance of the magnetic assembly.

An alternative view of FIG. 1( b ) is shown in FIG. 2 . The same 'U' shaped piece (101) is shown as (201) and the 'I' shaped piece (102) is shown as (202). The core (104) is shown as (204).

The next step in constructing the inductor is to wind a length of insulated copper around the core. In power electronics, this is often the copper foil, as shown in Figure 3. Here a copper sheet (304) is wound (302) together with an insulating sheet (303) around the core (301) of the inductor comprising a non-magnetic gap.

To mechanically support the core (204), the air gaps (105, 106) are filled with spacers (206, 207). The spacers (206, 207) must ideally exhibit low loss to any magnetic field, provide physical support to maintain core position, and have a thermal expansion coefficient sufficiently similar to that of the surrounding magnetic material to minimize mechanical stress within the assembly. Additionally, the spacers and glue should exhibit high thermal conductivity to assist in heat dissipation from the core (204). Examples of materials for these spacers (206, 207) include, but are not limited to, carbon fiber composites, beryllium oxide ceramics, and beryllium oxide filled epoxies.

Figure 4 shows different embodiments of such spacers (206, 207). Figure 4(a) shows a preferred embodiment, the form (401) has the same width and length as the core (204) and the same thickness as the ideal non-magnetic gap (105, 106). The form has a closed slot (404) into which glue can be inserted to permanently attach the members (201, 202, 204) before the magnetic assembly shown in Figure 2 is fitted together. Furthermore, the form (401) has notches (402, 403) cut into both sides of the form (301). These notches allow the form (401) to be flexible to expand along its length by an amount matching the thermal expansion of the magnetic material (201, 204, or 202, 204) to which it is attached.

Figure 4(b) shows an alternative embodiment (410) without a dedicated closed notch (such as 404) for containing glue. Instead, notches (411, 412) provide expansion flexibility and accommodate glue.

Figure 5(a) shows a modification of the spacers (401, 520) in which each end (521, 522) is shaped so that a small section is thicker and sized to overhang the magnetic core, As shown in Figure 5(b). The ends (506, 507, 521, 522) of the spacer (520) assist in maintaining the position of the core relative to the other magnetic pieces (501, 502).

An additional modification to the design of the preferred embodiment (401 ) is shown in Figure 5(c), in this example also with spacer ends (521, 522, 531, 532). Figure 5(c) shows the preferred embodiment (401, 520) from the side with additional corrugations of material (535, 536, 537) at the spacer connection to the core (504) face and U-shaped piece (501) causes the spacer to be uneven. This difference in height is introduced into the design of the spacer to cause equalization of the dimensions of the two non-magnetic gaps (105, 106, 115, 116), as well as flexibility in the thermal expansion of the spacer. Using the embodiment of Figure 5(c), an alternative embodiment would omit the use of epoxy as a fixation aid, as the spacer design and wraps (303, 304) are sufficient to maintain the core (114, 104, 204, 504) s position.

Referring to Figure 5(b) as an example, the assembly of the inductor described herein can be achieved by placing the core (504) in the body (501) and then placing the top piece (502) in place. Alternatively, the body (501 ) and top piece (502) may be assembled and the core then slid into place. For this second method of assembly, Figure 5(d) shows an additional design modification to the spacers used. The improvement uses the embodiment of Fig. 5(c) but can be applied to other embodiments with end caps, such as (521, 522, 531, 532, 561, 562). The improvement consists in forming a shorter end cap at one end of the spacer than described in the previous examples. In Figure 5(d), the end cap (562) is shorter, flush with the surface of the spacer opposite the core. This allows the core assembly to slide into place without interference. The other end cap (561) maintains the extra height (569) of the original end cap design, which will provide an end stop to ensure the core cannot slide past its correct position. In Figure 5(d), the lower portions of the two end caps (561, 562) are used to hold the core (567), thereby assisting in easy assembly.

Various other modifications and alterations in the structure and method of operation of this invention will be apparent to those skilled in the art without departing from the scope and spirit of this invention. Although the invention has been described in connection with specific preferred embodiments, it should be understood that the invention as claimed should not be unduly limited to such specific embodiments. It is intended that the following claims define the scope of the invention and that structures and methods within the scope of these claims and their equivalents be covered thereby.

Claims (20)

1. a kind of equipment including low-loss power inductor core body, it includes：

External magnetic core, it includes arranging the multiple magnetic core parts for being shaped as closed loop；

Internal magnetization core, it includes the mutually contradictory first end and second end separated by l shape magnetic core parts, And be arranged in the closed loop；

First non-magnetic spacers, it is arranged between the first end and the first inner side of the closed loop；And

Second non-magnetic spacers, it is arranged between the second end and the second inner side of the closed loop.

2. equipment according to claim 1, wherein, the multiple magnetic core part includes the first mutually contradictory C-shaped magnetic Property core body part and the second C-shaped magnetic core part.

3. equipment according to claim 1, wherein, the multiple magnetic core part includes the first mutually contradictory L-shaped magnetic Property core body part and the second L-shaped magnetic core part.

4. equipment according to claim 1, wherein, the multiple magnetic core part includes：

C-shaped magnetic core part；With

The 1 shape magnetic core part neighbouring with the open edge of the C-shaped magnetic core part.

5. equipment according to claim 1, wherein, the multiple magnetic core part includes：

, the l shape magnetic core part that is parallel to each other parallel with the internal magnetization core and the 2nd 1 shape magnetic core Part；With

, the threeth l shape magnetic core part that is parallel to each other vertical with the internal magnetization core and the 4th 1 shape magnetic core Part.

6. equipment according to claim 1, wherein：

First non-magnetic spacers are mechanically fastened between the first end and first inner side；And

Second non-magnetic spacers are mechanically fastened between the second end and second inner side.

7. equipment according to claim 1, wherein：

The first non-magnetic spacers adhesive fastener is between the first end and first inner side；And

The second non-magnetic spacers adhesive fastener is between the second end and second inner side.

8. equipment according to claim 1, wherein：

First non-magnetic spacers into longitudinal ripple shape, and by compression with the first end and first inner side thing Reason contact；And

Second non-magnetic spacers into longitudinal ripple shape, and by compression with the second end and second inner side thing Reason contact.

9. equipment according to claim 1, wherein, in first non-magnetic spacers and the second non-magnetic spacers At least one at least one longitudinal end than described in first non-magnetic spacers and the second non-magnetic spacers extremely Few one remainder is thick.

10. equipment according to claim 1, wherein, first non-magnetic spacers and the second non-magnetic spacers bag Include the overall structure with multiple holes.

A kind of 11. methods for manufacturing low-loss power inductor core body, including：

Closed loop as external magnetic core is formed by the use of multiple magnetic core parts；

To include that 1 shape magnetic core part of mutually contradictory first end and second end is positioned in the closed loop as inside Magnetic core part；

First non-magnetic spacers are positioned between the first end and the first inner side of the closed loop；And

Second non-magnetic spacers are positioned between the second end and the second inner side of the closed loop.

12. methods according to claim 11, wherein, the multiple magnetic core part includes the first mutually contradictory C-shaped Magnetic core part and the second C-shaped magnetic core part.

13. methods according to claim 11, wherein, the multiple magnetic core part includes the first mutually contradictory L-shaped Magnetic core part and the second L-shaped magnetic core part.

14. methods according to claim 11, wherein, the multiple magnetic core part includes：

C-shaped magnetic core part；With

The 1 shape magnetic core part neighbouring with the open edge of the C-shaped magnetic core part.

15. methods according to claim 11, wherein, the multiple magnetic core part includes：

, the one 1 shape magnetic core part that is parallel to each other parallel with the internal magnetization core and the 2nd 1 shape magnetic core Part；With

, the three 1 shape magnetic core part that is parallel to each other vertical with the internal magnetization core and the 4th 1 shape magnetic core Part.

16. methods according to claim 11, wherein：

Positioning the first non-magnetic spacers includes for first non-magnetic spacers being mechanically fastened to the first end and institute Between stating on the inside of first；And

Positioning the second non-magnetic spacers includes for second non-magnetic spacers being mechanically fastened to the second end and institute Between stating on the inside of second.

17. methods according to claim 11, wherein：

Positioning the first non-magnetic spacers is included the first non-magnetic spacers adhesive fastener in the first end and institute Between stating on the inside of first；And

Positioning the second non-magnetic spacers is included the second non-magnetic spacers adhesive fastener in the second end and institute Between stating on the inside of second.

18. methods according to claim 11, wherein：

Position the first non-magnetic spacers last with described first including the first non-magnetic spacers compression by longitudinal ripple shape End and the described first inner side physical contact；And

Position the second non-magnetic spacers last with described second including the second non-magnetic spacers compression by longitudinal ripple shape End and the described second inner side physical contact.

19. methods according to claim 11, wherein, in first non-magnetic spacers and the second non-magnetic spacers At least one at least one longitudinal end than described in first non-magnetic spacers and the second non-magnetic spacers At least one remainder is thick.

20. methods according to claim 11, wherein, first non-magnetic spacers and the second non-magnetic spacers bag Include the overall structure with multiple holes.