Antenna and method for producing antennas

Abstract

The present invention relates to an antenna and a method of manufacturing antennas. The antenna comprises: a magnetic core (1); one or more windings (2, 3) arranged around the core (1); and an electrically insulating base on which the magnetic core (1) provided with the winding or windings (2, 3) is arranged, the electrically insulating base integrating electrically conductive elements (20) provided for being connected to the windings (2, 3), where the electrically insulating base comprises two parts (5, 6) which are arranged in parallel, facing one another, and linked to the magnetic core (1). Each of the two parts (5, 6) provides a support portion, which support portions together constitute a support around the outer perimeter of which there is wound an external winding (4). The method comprises manufacturing the antenna of the invention by sequentially winding all the windings with a multi-axis winding machine.

Claims

1. An antenna comprising: at least one magnetic core; at least one winding wound around said magnetic core; and an electrically insulating base on which said magnetic core provided with said at least one winding is arranged, said electrically insulating base integrating electrically conductive elements connected to said at least one winding, where said electrically insulating base comprises at least two physically separated parts which are arranged, facing one another and providing a bottom seat attached to said magnetic core, wherein: each of said two parts provides a support portion, said support portions together constituting a support around the outer perimeter of which there is wound an external winding; and each of said two parts has protuberances in two distal end portions, each of the protuberances including two walls which form a corner and constitute said support portions, whereby said two parts provide four corners, one gap existing between said distal end portions of each part, and another gap existing between both separated parts.

2. The antenna according to claim 1 wherein said four corners are located at the vertices of a quadrangular perimeter, facing one another through inner faces, internally demarcating a housing for said magnetic core, and the outer faces of the four corners define said outer perimeter around which said external winding is wound.

3. The antenna according to claim 1, wherein a link between the two parts and said magnetic core is made by means of attachment of a basal area of the core on surfaces of said parts, which are separated, using a structural adhesive.

4. The antenna according to claim 1, wherein said two parts forming the base are identical and symmetrical, made of an electrically insulating plastic material, and said electrically conductive elements are embedded in the two parts and protrude from distal and/or lateral end portions thereof.

5. The antenna according to claim 3, wherein said distal end portions have a rectangular prismatic configuration and are attached to one another by a straight segment with a uniform section, as a strip, providing the surfaces for the attachment of said basal area of the magnetic core.

6. The antenna according to claim 1, wherein said at least one winding comprises two windings wound on said magnetic core, around respective coplanar, orthogonal axes, and a third external winding wound around said outer perimeter of said support, according to an axis perpendicular to the two preceding axes.

7. The antenna according to claim 6, wherein said magnetic core is a monolithic core and comprises a central part in the form of a quadrangular plate, having next to each of its four corners a prismatic turret protruding from the two larger faces of said central part, said turrets being linked in twos by strips adjacent to opposite sides of the central part, said strips protruding slightly from the larger faces of said central part determining a step, said central part and said strips providing supports for corresponding windings, which are spaced from one another, wound around respective coplanar, orthogonal axes and protected by an electrically insulating sheet.

8. The antenna according to claim 1, wherein said electrically conductive elements adopt the shape of projections protruding from one or more faces of the base and are provided for attachment with the end of one of the corresponding windings by means of welding.

9. The antenna according to claim 1, further comprising an adaptor arranged on the magnetic core integrating metal platings on a larger outer surface adapted for surface mounting of the antenna, said metal platings continuing on a side surface to establish contact with said electrically conductive elements of the parts of the electrically insulating base.

10. The antenna according to claim 3, wherein said end portions of the two parts further include metal platings in a basal area for connection to a circuit by surface mounting.

11. The antenna according to claim 2, wherein the walls of said support portions have a thickness sized to keep the external winding separated a distance from the at least one winding for minimizing stray capacitances and couplings between windings.

12. The antenna according to claim 11, wherein at least one projection made of an electrically insulating material extends in cantilever manner from at least part of an upper free edge of each of said walls in the direction opposite the housing.

13. A method of manufacturing antennas, the method comprising manufacturing an antenna according to claim 1 by means of performing at least the following steps: introducing and fixing said magnetic core in a housing demarcated by the inner faces of the four corners of the two physically separated parts of said electrically insulating base which have been obtained by molding on an intermediate element, as a metal strip, which provides said electrically conductive elements and keeps said two parts of the base attached to one another; cutting or eliminating said intermediate element which keeps the two parts of the electrically insulating base attached to one another, and sequentially winding with a multi-axis winding machine the at least one winding on the core and the external winding around the outer faces of at least the four corners wherein the at least one winding are first wound around the core according to axes orthogonal to one another, one of them passing through the gap existing between both parts and the other passing through the gap existing between distal end portions of each part, below segments that, as strips, join every two distal end portions to one another.

14. The method according to claim 13, further comprising arranging the external winding against said outer faces of at least the four corners without adhesive, the wire forming this external winding being exposed to the environment.

15. The method according to claim 13, further comprising associating with the antenna an adaptor integrating metal platings on a larger outer surface which are intended for surface mounting of the antenna, said metal platings continuing on a side surface to establish contact with said electrically conductive elements or terminals and welding said terminals to said metal platings of said adaptor.

16. The antenna according to claim 2, wherein a link between the two parts and said magnetic core is made by means of attachment of a basal area of the core on surfaces of said parts, which are separated, using a structural adhesive.

17. The antenna according to claim 4, wherein said distal end portions have a rectangular prismatic configuration and are attached to one another by a straight segment with a uniform section, as a strip, providing surfaces of said parts for attachment of a basal area of the magnetic core.

18. The antenna according to claim 3, wherein the walls of said support portions have a thickness sized to keep the external winding separated a distance from the at least one winding for minimizing stray capacitances and couplings between windings.

19. The antenna according to claim 18, wherein at least one projection made of an electrically insulating material extends in cantilever manner from at least part of an upper free edge of each of said walls in the direction opposite a housing for said magnetic core.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The foregoing and other advantages and features will be better understood from the following detailed description of several embodiments in reference to the attached drawings which must be interpreted in an illustrative and non-limiting manner, in which:

(2) FIG. 1 is a top perspective view showing the two parts of the electrically insulating base of the antenna proposed by the first aspect of the present invention for an embodiment;

(3) FIG. 2 shows the same elements as FIG. 1 but by means of a bottom perspective view;

(4) FIG. 3 shows an exploded perspective view of the two parts of the base of FIG. 1 and the magnetic core provided for fitting into the housing defined by same, according to an embodiment of the antenna proposed by the first aspect of the present invention;

(5) FIG. 4 shows a perspective view of the magnetic core once it is fitted into the housing defined by the two parts of the base with two windings wound around it and with an external winding wound around the corners of the walls protruding from the two parts of the base;

(6) FIG. 5 differs from FIG. 4 in that it schematically shows how the ends of the windings are braided before connecting them to the illustrated metal projections;

(7) FIG. 6 shows in detail the connection of some of the ends of the winding illustrated in FIG. 5, once braided, to some of the metal projections by means of welding;

(8) FIG. 7 illustrates a perspective view of an adaptor which is associated with the antenna proposed by the first aspect of the invention according to an embodiment, including metal platings on a larger outer surface which, when arranged on the magnetic core, contact the metal projections of the base, and which are intended for allowing the surface mounting of the antenna on a PCB board;

(9) FIG. 8 shows an exploded top perspective view of the adaptor of FIG. 7 arranged for being mounted on the magnetic core, covering all the windings, and for being fixed to the base;

(10) FIG. 9 shows a bottom perspective view of the adaptor once mounted on the magnetic core and fixed to the base;

(11) FIG. 10 differs from FIG. 9 in that it shows a label fixed on respective basal areas of the two parts of the base of the antenna proposed by the first aspect of the invention, for an embodiment;

(12) FIG. 11 shows an arrangement of two metal strips or lead frames arranged in parallel, integrating a plurality of metal terminals intended for being embedded in the electrically insulating parts of a plurality of bases of the antenna (which are injected molded on said metal strips in a known manner), the drawing illustrating only two parts of a base of an antenna, particularly of the antenna proposed by the first aspect of the invention, for an embodiment;

(13) FIG. 12 is also a view similar to that of FIG. 1 but for an embodiment for which a projection or perimetral flange extends in cantilever manner from the upper edge of each corner out of the housing; and

(14) FIG. 13 shows a perspective view of the two parts of the base of FIG. 12 and the magnetic core fitted into the housing defined by the parts according to an embodiment of the proposed antenna;

(15) FIG. 14 shows an embodiment alternative to that of FIG. 12, differing from said FIG. 12 in that the projection extending in cantilever manner is smaller and does not extend from the entire perimeter of the upper edge of each corner.

DETAILED DESCRIPTION OF SEVERAL EMBODIMENTS

(16) The attached drawings illustrate several embodiments of the antenna proposed by the present invention.

(17) Particularly, FIGS. 1, 2, 12 and 14 illustrate the two parts 5, 6 into which the base of the antenna of the present invention is split, for three different embodiments, but having in common, among other aspects, the fact that the two parts 5, 6 forming the base are identical and symmetrical, are made of an electrically insulating plastic material, and have electrically conductive elements 20, as projections, embedded in the mentioned parts 5, 6 and protruding from distal and/or lateral end portions 5a, 5b, 6a, 6b thereof.

(18) For the embodiments of FIGS. 1, 12 and 14, each of the two parts 5, 6 has protuberances in two distal end portions 5a, 5b, 6a, 6b, each of which includes two walls forming a corner 9, 10, 11, 12, such that the two parts 5, 6 provide four corners 9, 10, 11, 12 which are located at the vertices of a quadrangular perimeter, facing one another through inner faces, internally demarcating a housing 7 for the magnetic core 1, and the outer faces of the four corners 9, 10, 11, 12 define an outer perimeter around which an external winding 4 is wound.

(19) FIGS. 12 and 14 illustrate respective embodiments that differ from that of FIG. 1 in that they have projections 9a, 10a, 11a, 12a extending in cantilever manner from part of (in the case of FIG. 14) or from the entire (in the case of FIG. 12) upper edge of each corner 9, 10, 11, 12, out of the housing 7, in order to facilitate guiding while winding the external winding 4 and to prevent it from coming out by sliding.

(20) FIG. 13 illustrates the same embodiment as FIG. 12 but once the magnetic core 1 has already been fitted into and fixed in the housing 7.

(21) FIG. 2 illustrates the two parts 5, 6 of FIG. 1 by means of a bottom view which allows observing how the distal end portions 5a, 5b, 6a, 6b have a rectangular prismatic configuration and are attached by a straight segment 5c, 6c with a uniform section as a strip, orthogonal to the walls forming said corners 9, 10, 11, 12, and providing attachment surfaces for the basal area of the magnetic core 1.

(22) For a non-illustrated embodiment alternative to that of FIG. 2, the end portions 5a, 5b, 6a, 6b of the two parts 5, 6 further include metal platings in a basal area for connection to a circuit by surface mounting.

(23) FIG. 3 shows the magnetic core 1 of the antenna of the present invention in a situation before it is fitted into and fixed in the housing 7 defined by the two parts 5, 6, according to the same embodiment as FIG. 1. It can be observed that the magnetic core 1 is a monolithic core and comprises a central part 30 in the form of a quadrangular plate, having next to each of its four corners a prismatic turret 31 protruding from the two larger faces of said central part 30, said turrets 31 being linked in twos by strips 32, 33, adjacent to opposite sides of the central part 30, said strips 32, 33 protruding slightly from the larger faces of said central part 30 determining a step 34, said central part 30 and said strips 32, 33 providing supports for the corresponding windings 2, 3, which are spaced from one another, wound around respective coplanar, orthogonal axes and protected by an electrically insulating sheet.

(24) FIGS. 4, 5, 8 and 9 illustrate said two windings 2 and 3 wound around the core 1 and an external winding 4 wound around the four corners 9, 10, 11 and 12.

(25) FIG. 5 illustrates how the end of the windings, in this case the ends 4a and 4b of the external winding 4, must be braided (as indicated by the illustrated arrows) before fixing it to a respective metal projection 20 or terminal, FIG. 6 illustrating the end 4b once it is braided, having been wound several times on the projection 20, passing through the notch 21 preventing it from slipping and coming out of the projection 20, and a welding point 221 having been applied to fix it to the projection 20.

(26) FIG. 7 shows an adaptor 40 comprised by the antenna proposed by the first aspect of the invention according to an embodiment, including metal platings 121 extending from a larger surface 40a to side surfaces 40b which, when arranged on the base-core assembly, contact the metal projections 20 of the base, and which are intended for the surface mounting of the antenna on a PCB board. FIG. 8 illustrates a situation before mounting the adaptor 40 on the base-core assembly, and FIG. 9 (bottom view) illustrates a situation once the adaptor is mounted and fixed thereto, once the free ends of the side extensions of the metal platings 121 contact some of the projections 20.

(27) FIG. 10 shows the addition of a protective label fixed on the basal areas of the two parts 5, 6 on the assembly illustrated in FIG. 9.

(28) Finally, FIG. 11 illustrates an arrangement of two metal strips La, Lb, or lead frames, arranged in parallel, integrating a plurality of metal terminals T which are embedded in the electrically insulating parts (injection molded on said strips) of a plurality of antenna bases, the drawing illustrating only two parts 5, 6 of a base of an antenna, particularly of the antenna proposed by the first aspect of the invention, for an embodiment.

(29) Such metal terminals T are cut, being separated from the metal strip La, Lb, once the magnetic core 1 has been fixed to the base, such that the portions which are separated from the strips La, Lb, i.e., those protruding from the ends of the parts 5, 6, define the metal projections 20.

(30) Although FIG. 11 only illustrates the parts 5, 6 of a single base, the method proposed by the second aspect of the present invention applies to several metal strips La, Lb on which a plurality of parts 5, 6 of corresponding bases will be injection molded, a plurality of magnetic cores 1 finally being fixed thereto, one per base, and once they are all fixed, the different base-core assemblies formed are separated and part or all of them are wound in one and the same multi-axis winding machine simultaneously, or each of them separately, advantageously with the three windings 2, 3, 4.

(31) A person skilled in the art may introduce changes and modifications in the embodiments described without departing from the scope of the invention as defined in the attached claims.