EP3664220B1

EP3664220B1 - Dipole antenna and process for its manufacturing

Info

Publication number: EP3664220B1
Application number: EP19213427.8A
Authority: EP
Inventors: Andrea Negretti
Original assignee: Emme Esse SpA
Current assignee: Emme Esse SpA
Priority date: 2018-12-04
Filing date: 2019-12-04
Publication date: 2022-07-06
Anticipated expiration: 2039-12-04
Also published as: IT201800010786A1; ES2928236T3; EP3664220A1

Description

TECHNICAL FIELD

The present invention relates to the field of dipole antennas. The invention relates in particular to an antenna, of the dipole type, for use in outdoor environments and a process for the manufacturing thereof.

BACKGROUND ART

In the sector of antennas, in particular those of the dipole type, various types of antennas are known in relation to the particular use for which they are intended. In particular, they generally comprise at least one electrically conductive element and a connection device configured to make a connection of the conductive element itself to a signal line.
US 2018/219588 discloses a broadcast receiving apparatus comprising a first cover with a circuit board disposed therein, a second cover coupled to the first cover and at least one dipole antenna coupled to the circuit board and including an antenna pattern arranged on an inner surface of the second cover.
GR 1 008 497 describes an antenna for use in outdoor environments and suitable for the reception of digital television channels, comprising a dipole consisting of a brass sheet coupled to a substrate of dielectric material. The antenna allows the reception of radio/tv frequencies in the UHF region (400-846 MHz).
With particular regard to the use of such antennas in the outdoor environment, suitable protection with respect to environmental factors of the components used for making them is generally provided; in fact, the aforesaid components can get worn and/or damaged over time, until the correct operation of the antenna is compromised.
For this purpose, the electrically conductive elements can be made of metal alloys containing particular alloy elements adapted to provide suitable properties of resistance to corrosion and/or wear, whereas the connection elements are usually contained in appropriate box elements, that form the desired protection.
As an alternative to the use of particular metal alloys to be used in the outdoor environment as indicated above, the conductive elements can be made of metal alloys that do not comprise elements offering the properties of resistance to atmospheric agents, with the measure of applying a coating through protective materials such as, for example, compounds with a plastic matrix. Such alternative solution implies a partial reduction in the cost of the raw materials used, as such alloys are less select.
However, also according to such process, the problem regarding the complexity of the manufacturing process described above remains and is perhaps even increased, as a further processing step is required in order to make the coating of the conductive elements.
In this context, document IT 0001411117 illustrates a dipole antenna for the reception and transmission of television signals and/or data in frequency comprising a connection device - defined as a connection board - and at least one electrically conductive element connected thereto. The connection board and at least one portion of the electrically conductive element are provided with a coating made of plastic material, which is formed on them through injection moulding or through the covering of resins, directly in contact with the connection board and with the electrically conductive element, so as to cover them. The antenna further envisages a connection terminal for the signal line, at the output from the connection board; such terminal may be represented by a connector.
However, such solution, although achieving a reduction in costs and manufacturing times with respect to dipole antennas pertaining to the prior art, implies some drawbacks.
In the first place, the amount of pressure necessary for the process of injecting plastic material, and exerted on the connection board during the moulding step, can cause misalignments of the board with respect to the elements adjacent thereto or even the bending thereof.
As well as this, if the coating is not performed in a workmanlike manner, the humidity generated during the moulding process can remain trapped in the interface area between the connection board and the coating performed, causing over time a deterioration of the circuits present in the board itself.
The process used can also lead to undesired infiltrations of plastic material at the base of connection elements of the connection board with the signal line, such as the connector at the output from the board itself, which can cause the malfunctioning of the dipole.
In short, the process known from IT 0001411117 requires particular attention in the identification of the process parameters during the design stage, and control thereof during the manufacturing stage, so that the final product has a good degree of quality.

OBJECTS AND SUMMARY OF THE INVENTION

An object of the present invention is to overcome the disadvantages of the prior art.
In particular, an object of the present invention is to present a process for the manufacturing of an antenna of the dipole type, which allows the number of processing steps to be contained as much as possible as well as the time for performing them, at the same time maintaining a high degree of protection of the antenna with respect to external wearing agents.
A further object of the present invention is that of presenting a process for manufacturing antennas that is easy to plan and regulate, and reliable over time.
Finally, an object of the present invention is that of making an antenna of the dipole type for use in outdoor environments that has improved resistance to wear and to deterioration over time of the elements that compose it.
These and other objects of the present invention are achieved by a process and a device incorporating the features of the accompanying claims, which form an integral part of the present description.
The present invention relates to a process for manufacturing antennas of the dipole type according to claim 1.
Such solution allows the processing steps necessary for manufacturing the antenna to be reduced. Therefore, the management of the process is simplified, allowing at the same time an antenna to be made that has improved characteristics of resistance to external wearing agents. Furthermore, the regulation of the process parameters is simplified, with particular regard to the creation of the coating. In fact, this solution does not provide for complex covering phases of the elements, such as for example the printed circuit board, which are sensitive to the applied pressure and/or to humidity.
According to a further aspect the invention relates to an antenna of the dipole type according to claim 5.
According to such solution an antenna of the dipole type is created for use in outdoor environments provided with improved resistance to wear and to deterioration over time of the elements that compose it. The combination of a use of coating materials on the electrically conductive elements with the presence of suitable elements for covering the electronic components, allows each component to be better protected. The provision of a housing area, in which to position the printed circuit board, makes the step of assembly and connection of the connection terminals for allowing the transmission of the signal easy and safe.
The present invention in at least one of the aforesaid aspects may have at least one of the following preferred features, taken individually or in combination with any other one of the preferred characteristics described.
Preferably, the printed circuit board comprises a connector adapted to make a connection between said printed circuit board and a signal line.
Preferably, the covering element comprises fixing elements configured to removably connect the covering element itself to the housing area of the coating.
In this way, the accessibility to the components present inside the covering element is improved, so as to allow the possible replacement thereof in the event of malfunctioning or breakdown or simply the possibility to perform periodic inspections or cleaning operations.
Preferably, the covering element has at least one opening configured so as to allow the housing of a connector adapted to make the connection between the printed circuit board and a signal line.
Preferably, the electrically conductive element has a substantially elongated laminar profile.
Preferably, the antenna comprises at least two electrically conductive elements extending in a radial direction, starting from an axis of symmetry X, wherein each of said two electrically conductive elements has a substantially annular shape. Even more preferably, the axis of symmetry coincides with the axis of symmetry of the antenna.
Preferably, the antenna comprises fixing means adapted to connect it to a respective support. Preferably, said fixing means comprise at least one portion formed in one-piece with the coating in plastic and/or resin.
Further features and advantages of the present invention will be more apparent from the description of the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will be described below with reference to some examples, provided for explanatory and non-limiting purposes, and illustrated in the accompanying drawings. These drawings illustrate different aspects and embodiments of the present invention and, where appropriate, reference numerals illustrating similar structures, components, materials and/or elements in different figures are indicated by similar reference numbers.

Figure 1 is an exploded view of an antenna of the dipole type according to a first embodiment of the present invention;
Figure 2 is an exploded view of the antenna of Figure 1 in a first variant;
Figure 3 is a schematic view of a portion of the antenna of Figure 2 according to a further variant;
Figure 4 illustrates a second embodiment of a portion of antenna according to the present invention; and
Figure 5 illustrates a third embodiment of a portion of antenna according to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

While the invention is susceptible to various modifications and alternative constructions, certain preferred embodiments are shown in the drawings and are described hereinbelow in detail. It is in any case to be noted that there is no intention to limit the invention to the specific embodiment illustrated, rather on the contrary, the invention intends covering all the modifications, alternative and equivalent constructions that fall within the scope of the invention as defined in the claims.
The use of "for example", "etc.", ʺorʺ indicates non-exclusive alternatives without limitation, unless otherwise indicated. The use of ʺincludesʺ means "includes, but not limited to", unless otherwise indicated.
With reference to Figures 1 - 5, an antenna 1 of the dipole type is illustrated, according to the present invention.
In particular, the antenna 1 can comprise one or more electrically conductive elements 2 configured to form a dipole adapted for the reception and transmission of signals in the form of electromagnetic waves. Each electrically conductive element is provided with at least one end portion 3, at which there is an antenna terminal 4.
The antenna 1 further comprises a printed circuit board 7, which substantially comprises a support on which mutual board terminals 4' are provided which, in association with the antenna terminals 4 present on the electrically conductive elements 2, allows an electrical connection between the dipole created by the at least one electrically conductive element 2, and the printed circuit board 7.
Preferably, the printed circuit board 7 is provided with a device for the connection to the signal line and the circuitry (not shown in the figures) necessary for the transmission of the signal from the dipole towards the signal line itself.
Preferably, such device for the connection to the signal line is comprised of a connector 11.
The antenna 1 can be made according to various configurations, in particular in relation to the conformation of the at least one electrically conductive element 2, which can be designed based on the technical-functional characteristics necessary for the particular use of the antenna itself.
With reference to figures 1-3, a first embodiment of the antenna 1 contemplates the use of a single electrically conductive element 2 with a folded shape according to two substantially open annular elements 8, so as to have a shaped connection portion 15 of said annular elements 8 and two free end portions 3 facing one another. Preferably, on each of the two end portions an antenna terminal 4 is arranged.
The electrically conductive element 2 preferably has a substantially elongated laminar profile, whose cross section is generally rectangular or however has a prevalent dimension with respect to the other.
However, other possible geometries both of the profile and the cross section of the electrically conductive element 2 are possible, which are adapted to the making of dipoles for antennas.
The antenna 1 also has a coating 5 which can be made of plastic and/or resin, preferably by means of an appropriate process such as, for example, thermoforming, dip coating, etc. Preferably the coating 5 is made by injection moulding.
Such coating 5 extends along the entire longitudinal dimension of the electrically conductive element 2 leaving the antenna terminals 4 present near the end portions 3 free.
This provides an appropriate protection with respect to atmospheric agents in use in an outdoor environment of the electrically conductive element 2, while allowing easy access to be provided to the elements necessary for making an electrical connection.
Said coating 5 also has, in an own front portion, a housing area 6, in which the antenna terminals 4 are arranged, without coating, and arranged in a substantially intermediate position between the two annular elements 8.
Such housing area 6 is advantageously shaped so as to contain the printed circuit board 7 in a mutual support relationship, and to allow the contact between the antenna terminals 4 and the respective board terminals 4' so as to create the electrical connection between the electrically conductive element 2 and the printed circuit board 7.
The antenna 1 further has at least one covering element 9, which covers the printed circuit board 7 so as to provide suitable protection against external wearing agents, such as atmospheric agents, dust and/or humidity.
The covering element 9 can comprise fixing elements 12 configured to connect the covering element 9 itself to the housing area 6, preferably in a removably manner.
In this way, the simplicity of access to the components contained by the covering element 9 is increased, allowing easy maintenance and/or replacement of the components themselves.
In a preferred solution, such fixing elements 12 are made as a single part through moulding with the at least one covering element 9.
The covering element 9 preferably also has at least one opening 10 configured so as to allow the housing of a connector 11 adapted to make the connection between said printed circuit board 7 and the signal line. Said opening 10 is created on a surface of the covering 9 itself, in the position considered easiest for connecting the connector 11 to the relative terminal of the signal line.
According to a possible variant, shown in Fig. 1, such opening 9 is arranged on a front surface of the covering element 9. In a possible further preferred embodiment, shown in Fig. 2, such opening 9 is arranged on a lower surface of the covering element 9.
In a preferred embodiment, as shown in Fig. 3, the coating 5 can advantageously comprise slots 16, made at the housing area 6, and configured so as to allow the ventilation of the interface area between the printed circuit board 7 and the housing area 6.
According to a preferred embodiment, such slots 16 have an elongated shape and are arranged parallel to one another.
Through such expedient, it is possible to contain any undesired temperature increases in such interface area, preserving the electronic components present therein. Furthermore, still thanks to the ventilation of such area, the possibility of undesired stagnation of humidity, which could over time damage the aforesaid electronic components, is substantially reduced.
According to a preferred embodiment of the invention shown for example in Figures 1 and 2, the antenna 1 further comprises a protection element 17, arranged in a rear part of the coating 5, at the housing area 6, adapted to protect the antenna terminals 4, which can be free from the coating 5 also in the rear part thereof. Such protection element 17 advantageously also allows protection with respect to the atmospheric agents of the area affected by the slots 16, if provided.
With reference to Fig. 4, a second embodiment of the structure of the dipole of the antenna 1 according to the present invention, contemplates providing two electrically conductive elements 2, which extend in the radial direction starting from an axis of symmetry X of the antenna. Preferably, the two electrically conductive elements 2 are arranged symmetrically with respect to said axis of symmetry X.
According to such solution, each electrically conductive element 2 has a closed circular annular shape and comprises an end portion 3 that extends radially towards the housing area 6.
Preferably, the respective end portions 3 of the two electrically conductive elements 2 are arranged symmetrically with respect to the axis X and face each other mutually so as to arrange the relative antenna terminals 4 in proximity to the housing area 6.
The coating 5 can be made according to the same methods envisaged for the embodiments described above with reference to figures 1 to 3.
With reference to Fig. 5, a third possible embodiment of the structure of the dipole of the antenna 1 contemplates providing two electrically conductive elements 2, each of which has a closed squared annular shape, substantially rectangular.
Preferably, for both of the configurations described above with reference to Fig. 4 and 5, one or more variants are possible including the possibility of providing appropriate slots 16 made at the housing area 6, or arranging a protection element 17, at the rear part of the coating 5.
Also preferably, in any embodiment and/or variant from among those described, the antenna 1 can comprise fixing means 13 adapted to connect the antenna to a respective support. Said fixing means 13 can advantageously comprise at least one portion 14 formed in one-piece with the coating 5 in plastic and/or resin.
With reference in particular to figures 1 and 2 described below, a preferred embodiment of the manufacturing process according to the invention is described for the manufacturing of the antenna 1.
First of all one or more electrically conductive elements 2 are arranged, comprising at least one antenna terminal 4 on a corresponding own end portion 3, in a mould of an apparatus for injection moulding.
Therefore, a coating 5 is created so as to cover the electrically conductive element(s) 2 present in the mould, leaving the antenna terminals 4 free. The creation of the aforesaid coating further provides the formation of a housing area 6, preferably made in one-piece with the coating 5. Preferably, the coating 5 almost entirely covers the electrically conductive elements 2; further embodiments are possible which envisage the partial covering of the electrically conductive element(s) 2, based on specific needs such as, for example, the need to contain the weight and/or costs of making the antenna 1.
The particular conformation of such shaped housing area 6 is made possible by the process used, i.e. injection moulding, which allows elements with a complex shape to be made, adapting the design of the mould to the specific techniques or aesthetics desired.
Advantageously, such housing area 6 is appropriately modelled to house the printed circuit board 7 creating a seat in which it can be positioned in a mutual support relationship.
In said housing seat 6 there are also antenna terminals 4, left free by the coating 5 and arranged so as to be able to be coupled with the respective board terminals 4' present on the printed circuit board 7.
In a step subsequent to the creation of the coating 5, according to the methods described above, the process comprises a step in which the printed circuit board 7 is positioned in the housing area 6 so as to connect the mutual antenna terminals (4) and board terminals (4') to one another and therefore create an electrical connection between the dipole made by the conductive elements 2 and the printed circuit board 7.
Preferably, the process comprises a further step for positioning a covering element 9 at the printed circuit board 7 and closing it onto itself by means of fixing elements 12, so as to create a coating thereof. Said fixing elements 12 can be made in a single piece with the covering element 9, through moulding. According to a preferred embodiment the fixing elements 12 are adapted to removably connect the covering element 9 to the housing area.
The invention thus conceived is susceptible to several modifications and variations, all falling within the scope of protection defined by the appended claims.

Claims

Process for manufacturing antennas (1) of the dipole type comprising:
- providing in a mould at least one electrically conductive element (2) comprising at least one antenna terminal (4) arranged on a corresponding own end portion (3), said electrically conductive element (2) being configured to form a dipole adapted for the reception and transmission of signals in the form of electromagnetic waves;

- making a coating (5) of said electrically conductive element (2) by means of a plastic material and/or resin, so as to cover the electrically conductive element (2) present in the mould, leaving said at least one antenna terminal (4) free, and forming a shaped housing area (6) in which said at least an antenna terminal (4) is arranged, said shaped housing area (6) being made in one-piece with the coating (5);

- arranging in the housing area (6) a printed circuit board (7) comprising at least one board terminal (4');

- electrically connecting said at least one antenna terminal (4) to a corresponding board terminal (4');

- fastening at least one covering element (9) in correspondence with said housing area (6) so as to define a volume in which the printed circuit board (7) is housed.
Process according to claim 1, wherein the printed circuit board (7) comprises a connector (11) adapted to make a connection between said printed circuit board (7) and a signal line.
Process according to claim 1 or 2, wherein said fastening at least one covering element (9) takes place by means of fixing elements (12), configured to removably connect the covering element (9) to the housing area (6).
Process according to any one of claims 1 to 3, wherein said making a coating (5) so as to cover the electrically conductive element (2) present in the mould and forming a shaped housing area (6), is made by injection moulding.
Antenna (1) of the dipole type comprising:
- at least one electrically conductive element (2) comprising at least one antenna terminal (4) arranged on a corresponding own end portion (3), said electrically conductive element (2) being configured to form a dipole adapted for the reception and transmission of signals in the form of electromagnetic waves;

- a coating (5), made of plastic material and/or resin, extending along a longitudinal dimension of said at least one electrically conductive element (2) and covering the electrically conductive element (2) leaving said antenna terminal (4) free and forming a housing area (6) in which said at least one antenna terminal (4) is arranged, said housing area (6) being made in one-piece with the coating (5);

- a printed circuit board (7) comprising at least one board terminal (4'), arranged within said housing area (6) which is shaped so as to contain the printed circuit board (7) in a mutual support relationship, so as to allow the contact between the at least one antenna terminal (4) and the respective board terminal (4') and to provide an electrical connection between the electrically conductive element (2) and the printed circuit board (7); - at least one covering element (9) removably fastened to the housing area (6) of the coating (5) and adapted to form, with the housing area, a housing volume which houses the printed circuit board (7).
Antenna (1) according to claim 5, wherein the printed circuit board (7) comprises a connector (11) adapted to make a connection between said printed circuit board (7) and a signal line.
Antenna (1) according to claim 5 or 6, wherein said covering element (9) comprises fixing elements (12) configured to removably connect the covering element (9) to the housing area (6).
Antenna (1) according to claim 6 or according to claim 7 when dependent on claim 6, in which said covering element (9) has at least one opening (10) for housing the connector (11).
Antenna (1) according to any one of the claims from 5 to 8, wherein said at least one electrically conductive element (2) has a substantially elongated laminar profile.
Antenna (1) according to any one of the claims from 5 to 9, comprising at least two electrically conductive elements (2) extending in a radial direction, starting from an axis of symmetry X, wherein each of said two electrically conductive elements (2) has a substantially annular shape.
Antenna (1) according to any one of the claims from 5 to 10, comprising fixing means (13) adapted to connect the antenna to a respective support, wherein said fixing means (13) comprise at least one portion (14) formed in one-piece with the coating (5) in plastic and/or resin.