EP4648224A1

EP4648224A1 - Monopole antenna for motor vehicles, and motor vehicle comprising such antenna

Info

Publication number: EP4648224A1
Application number: EP25171228.7A
Authority: EP
Inventors: Matteo Cerretelli; Luca Ferrari; Andrea Notari; Fabio CASOLI; Stefano SCORCIONI
Original assignee: Ask Industries SpA
Current assignee: Ask Industries SpA
Priority date: 2024-05-07
Filing date: 2025-04-17
Publication date: 2025-11-12

Abstract

Monopole antenna (100) for a motor vehicle, comprising:
- a radiating element (1) for transceiving signals;
- a printed circuit board (2);
- a containment enclosure connectable to a mounting part of the vehicle and comprising a first component (4) and a second component (5) that are coupled together and are configured to define internal housing spaces for at least the radiating element and the printed circuit board. The first component (4) includes a base wall (12), side walls (14) extending transversely from the perimeter edge of the base wall, and an inner wall (16) extending transversely from the base wall parallel to and spaced from the side walls.

The inner wall laterally delimits an inner space (17) housing electronic components of the antenna. The printed circuit board is attached to the top edge (18) of the inner wall by means of a layer (19) of electrically conductive glue that is applied along the top edge (18) and allows bonding the printed circuit board to the first component. The first and second components are connected by a waterproof joint (6).

Description

The present invention relates to a monopole antenna for motor vehicles and to a motor vehicle comprising such antenna.
The antenna according to the invention is especially suitable for being used in cars, e.g., mounted in hidden parts of a car, such as the metallic bar inside the bumper, and it will be described herein with reference to this use without limiting its possible applications on other types of motor vehicles, such as buses, trucks, commercial vehicles, etc., as well as for installation on other parts of motor vehicles.
As it is known, monopole antennas intended for the installation on a motor vehicle, e.g., on the roof or on any other of its metallic surfaces suitable for its installation, comprise an enclosure which houses a radiating element suitable for transceiving signals and associated electronic components, typically comprising a printed circuit board, which properly processes the signals to be transceived.
Such antennas should satisfy some basic requirements, and in particular they should guarantee the most effective transceiving of signals over time.
To this end, because of their use, these antennas should have a structure which resists atmospheric agents, and in particular which has a substantially tight seal against water infiltrations, and they should offer a proper and lasting connection between functional and/or structural parts, e.g., between the radiating element and the associated printed circuit board, or between one of them, or both, and the enclosure.
Moreover, such characteristics should be achieved in the most simple and optimized manner, both in terms of production aspects of the various parts, and, especially, in terms of their assembly and installation.
Although monopole antennas currently on the market allow somehow to meet these requirements, there are some aspects susceptible to improvement, in particular concerning the waterproof seal, and the manner and difficulty with which the various parts can be assembled and operationally connected with each other.
Therefore, a scope of the present invention is to provide a monopole antenna for motor vehicles which allows improving, at least partially, one or more of these aspects, or that anyway represents an alternative solution compared to the known solutions and which can be realized in the most optimized manner possible.
This scope and others which will possibly result from the following description are achieved by a monopole antenna for a motor vehicle whose features are defined in claim 1.
This scope and others which will possibly result from the following description are also achieved by a motor vehicle according to claim 11.
Particular embodiments form the subject of dependent claims, the content of which is intended as an integral part of the present description.
Further features and advantages of the invention will become clear from the following detailed description, performed by way of non-limiting example, with reference to the attached drawings, in which:

Figure 1 is an exploded view illustrating a possible embodiment of various components of the monopole antenna according to the invention;
Figure 2 illustrates the antenna of figure 1 with the various components assembled;
Figure 3 is a view illustrating a possible embodiment of an electrical contact coupled to a printed circuit board and to a radiating element used in the monopole antenna according to the invention;
Figure 4 is a perspective view illustrating a component of a containment enclosure which is part of the antenna according to the invention.

It should be noted that in the following detailed description, identical or similar components, from a structural and/or functional point of view, may have the same or different reference numbers, regardless of whether they are shown in different embodiments or in separate parts in the present invention.
It should also be noted that, in order to clearly and concisely describe the present invention, the drawings may not be to scale and some features of the description may be shown in a somehow schematic form.
Moreover, when the term "adapted", or "configured", or "shaped", or a similar term is used in the present document, with reference to any component as a whole, or to any part of a component or of a combination of components, it should be intended that it means and correspondingly comprises the structure and/or configuration and/or shape and/or positioning.
In addition, when the term "substantial", or "substantially" is used herein, it should be intended as comprising a variation due to unavoidable construction tolerances, or a current variation of more or less 5% with respect to what is indicated as reference value, direction or position, and when the terms "transversal" or "transversely" are used herein they should be intended as comprising a direction that is non-parallel to the reference part or parts or to direction(s)/axis to which they refer, and the perpendicularity should be considered a specific case of transversal direction.
Finally, in the following description and claims, the ordinal numbers first, second, etc., will be used for the sake of illustrative clarity and in no way they should be intended as limiting for any reason, nor that the order must exactly be the one in the sequence described with reference to the embodiments described. For example, the indication of a second portion does not imply that a first one necessarily exists, and vice versa.
Figure 1 and 2 illustrate an antenna 100 according to the invention, showed with its various components disassembled and assembled with each other, respectively.
The antenna 100 according to the invention comprises at least:

a radiating element 1 for receiving and transmitting (hereinafter "transceiving") signals from and to the environment outside the antenna 100;
a printed circuit board 2 (or PCB);
a containment enclosure suitable for being connected to a mounting part of a motor vehicle and comprising at least a first component 4 and a second component 5 coupled with each other and configured to define one or more internal housing spaces for at least the radiating element 1 and the printed circuit board 2.

Usefully, as illustrated in detail in figure 4, the first component 4 of the containment enclosure comprises at least:

a base wall 12;
one or more lateral walls 14 which transversely protrude from the peripheral edge of the base wall 12; and
an inner wall 16 which transversely protrudes from the base wall 12 parallel to and spaced from one or more side walls 14, e.g., for a height (measured from the base wall 12 itself) higher than the height of one or more first lateral walls 14.

In particular, the inner wall 16 laterally delimits, at least in part, an inner space 17 suitable for housing one or more electrical components (not illustrated in the figures) of the antenna 100.
Conveniently, in the antenna 100 according to the invention, the printed circuit board 2 is fixed on the upper edge 18 of the inner wall 16, opposite with respect to the first base wall 12.
In particular, the antenna 100 according to the invention comprises a layer of electrically conductive glue, indicated in figure 4 with the dotted line 19, which is applied along at least part of said upper edge 18 of the inner wall 16 and suitable for allowing the bonding of the printed circuit board 2 to the first component 4 of the enclosure itself.
In this way, an electrical continuity between the printed circuit board 2 and the first component 4 is established that provides a connection to ground ("grounding") and acts as a shielding for the electrical components placed in the inner space 17.
Usefully, in the antenna 100 according to the invention, the first component 4 and the second component 5 are connected to each other at least by a waterproof junction (indicated with the dotted line 6 in figure 4) in order not to substantially allow the penetration of external agents, in particular of water, inside the inner area delimited by the junction 6 itself.
In the illustrated embodiment, the first component 4 comprises also a mounting bracket 10 which transversely protrudes from the base wall 12, with the one or more side walls 14 which transversely protrude from the peripheral edge of the base wall 12 parallel to and towards the mounting bracket 10.
The mounting bracket 10 is configured to allow the assembly of the antenna 100 on the motor vehicle, e.g., on the bar of the bumper or on another metallic surface suitable for the assembly, according to known manners or readily implementable manners by one skilled in the art, and not relevant for the purpose of the present invention anyway, so not described in detail herein.
In a possible embodiment, one or more hooking teeth 13 are provided along the external surfaces of one or more side walls 14.
For example, in a possible embodiment the first component 4 is realized in an electrically conducing material, e.g., zamak alloy.
In a possible embodiment, the antenna 100 further comprises an electrical contact 3 which is configured to electrically connect the radiating element 1 to the printed circuit board 2, realizing the electrical continuity also between the radiating element 1 and the printed circuit board 2.
In a possible embodiment, the electrical contact 3 is configured to connect the printed circuit board 2 to the radiating element 1 in a structurally removable manner.
In the embodiment illustrated in figures 1 and 2, the radiating element 1 comprises a body, realized in an electrically conducing material, which has at least a first portion 1A having a substantially planar development, on which proper drilling and notching are obtained, and a tooth 1B protruding transversely from the first portion 1A, in particular, perpendicular from it.
As it will result more detailed from the following description, the tooth 1B is configured to couple with an associated portion 3B of the electrical contact 3.
The printed circuit board 2 comprises, according to well known embodiments, a body having a substantially rectangular development, on which one or more electrically conductive tracks are provided.
Along a side of the printed circuit board 2, there is placed a connector 7 which allows to connect an external coaxial cable that delivers the signals (and that typically connects to the radio of the motor vehicle or generally to the Remote Telemetry Control Unit-RTCU, which comprises, for example, GPS, radio, etc.), to one or the principal track present on the printed circuit board 2, which, by means of proper active or passive components, is then directly connected with the radiating element 1 by means of the electrical contact 3.
Conveniently, the body of the printed circuit board 2 is provided with a pass-through opening 8.
Usefully, as illustrated in figure 3, the electrical contact 3 comprises a shaped body, realized in an electrically conductive material, which has a first portion 3A welded to the printed circuit board 2, and a second portion 3B suitable for pressure coupling with an associated portion of the radiating element 1, and in particular with the tooth 1B indicated above.
In particular, in a possible embodiment the electrical contact comprises a clip- or pin-shaped body.
For example, as illustrated in figure 3, the electrical contact 3 has a base portion 3A, having a substantially planar development, from which two elastic arms protrude from opposite sides to each other.
The two elastic arms have both a lower part which converges with the lower part of the other arm and a second part which diverges from the second part of the other arm and they overall form the portion 3B.
The base portion 3A is provided with a slit 3C.
When the electrical contact 3 is soldered to the printed circuit board 2, the base portion 3A is positioned with the slit 3C overlapping the pass-through opening.
In this way, during the assembly, the tooth 1B of the radiating element 1 is passed through the opening 8 and the slit 3C, by going into the two arms of the electrical contact 3 which, elastically reacting, will press the tooth 1B itself between each other.
In this way, the radiating element 1 is electrically connected to the printed circuit board 2, for example at least to one of its conductive tracks.
In turn, the second component 5 of the containment enclosure is realized e.g., in a plastic material and it comprises a first portion 5A having a substantially planar development inside which a portion of the radiating element 1 is housed.
In particular, the radiating element 1 is housed inside the first portion 5A with a predominant part, i.e., more than 50% of its total volume.
In the illustrated embodiment, the second component 5 of the containment enclosure comprises at least a second portion 5B configured substantially in the form of a box open on one side and including a back wall 20, opposite the open side, one or more second side walls 22 which protrude transversely from the back wall around an interior space 24 suitable for housing the printed circuit board 2.
For example, the first portion 5A comprises or consists of a sort of co-molded shell with the radiating element 1, with a lower portion of the radiating element 1 itself, in particular with at least the tooth 1B protruding from the lower part of the first portion 5 protruding inside the space 24.
From a side of the second box portion 5B a channel 25 protrudes which connects the interior space 24 with the external part of the containment enclosure and it is intended to receive the connector 7 from the printed circuit board 2.
The channel 25 is properly configured to guarantee the mechanical coupling (not shown in the figures) with an associated connector which is placed on the motor vehicle wiring and which in turn generates on that side the waterproof joint in the area 24, once it is connected.
Usefully, in one possible embodiment, the waterproof joint 6 comprises or consists of a layer of glue or of sealant that is applied along at least part of one of the top edge of one or more first side walls 14 of the first component 4 and the top edge of one or more second side walls 22 of the second component 5, and is suitable for allowing bonding between said first and second components 4, 5.
In the embodiment illustrated in the figures, the layer 6 is shown as applied along at least part of the top edge of one or more first side walls 14 of the first component 4.
Moreover, in a possible embodiment, on the external surface of one or more second side walls 22 one or more hooking sites 27 suitable for receiving each a corresponding hooking tooth 13 are provided so to guarantee the mechanical coupling between the two components 4 and 5, until the sealant/glue is not completely solidified.
Practically, during the assembly step (and in any assembly sequence possible), the printed circuit board 2 is inserted inside the space 24 by tilting it so to make the connector 7 enter inside the guide 25. Once the positioning is complete, the printed circuit board 2 is pressed towards the back wall 20 with the tooth 1B which enters into the opening 8 and goes between the arms of the electrical contact 3 widening them and making contact with the electrical contact 3 itself. The printed circuit board 2 is fixed by screws 9.
In one embodiment, the component 4 is then coupled to the component 5 with the hooking teeth 13 that each fit into a corresponding hooking site 27; the glue layer, which forms the junction 6, allows the bonding between the two components 4 and 5.
During this step, there are also the contact and bonding of the printed circuit 2 on the electrically conductive glue layer 19 which is applied along at least part of the upper edge 18.
It has been made evident that the antenna 100 according to the invention properly fulfils the intended purpose as it has a structure which, compared to the known solutions, allows obtaining an optimized assembly, and in which electrical continuity is established between the printed circuit board 2 and the component 4 of the enclosure, with at least the junction 6 which guarantees a waterproof joint. Moreover, thanks to the contact 3, the electrical continuity between the radiating element 1 and the printed circuit board 2 is established in a simple and effective way.
Moreover, the antenna 100 has a structure that makes it suitable for being used either in new motor vehicles or to substitute already installed antennas on motor vehicles in use.
Naturally, given the principle of the invention, the embodiments and the particular of the embodiments may be widely varied with respect to what has been described and illustrated by way of non-limiting example, without for this reason without going out the scope of protection of the present invention defined by the appended claims, comprising any possible combination, also in part, of the previously described embodiments.
For example, in a possible embodiment, the first component 4 can be made of metal or of another electrically conductive material, e.g., a plastic material which is properly charged with electrically conducing particles, and it may be applied to the component 5 by means of other technologies (e.g., welding between plastic materials).
In particular, in one possible embodiment the waterproof joint 6 comprises or consists of a weld 6 obtained by welding directly the first component 4 with the second component 5.
For example, the waterproof weld 6 can be realized along at least part of one of the top edge of one or more first side walls 14 of the first component 4 and the top edge of one or more second side walls 22 of the second component 5.
For example, the joining weld 6 can be obtained via ultrasonic welding, however any other suitable type of welding technique can be used.
The first component 4 can be realized in more pieces separate with each other, e.g., the bracket 10 can be structurally separated from the rest of the component body 4 and it can be separately connected to the second component 5. For example, the bracket 10 can have an L-shaped configuration with a first side protruding transversally from the base wall 12 and a second side inserted in the structure of the base wall 12 and co-molded therewith.

Claims

Monopole antenna (100) for a motor vehicle, characterized by comprising at least:
- a radiating element (1) for transceiving signals with the environment outside the antenna (100);

- a printed circuit board (2);

- a containment enclosure suitable for being connected to a mounting part of a motor vehicle and comprising at least a first component (4) and a second component (5) which are coupled together and are configured to define one or more internal housing spaces for at least the radiating element (1) and the printed circuit board (2), wherein said first component (4) comprises at least a base wall (12), one or more first side walls (14) which protrude transversally from the perimeter edge of the base wall (12), and an inner wall (16) which protrudes transversally from the base wall (12) parallel to and spaced from the one or more first side walls (14), said inner wall (16) laterally delimiting, at least in part, an inner space (17) suitable for housing one or more electronic components of the antenna (100), wherein said printed circuit board (2) is fixed to the upper edge (18) of said inner wall (16) by means of a layer (19) of electrically conductive glue which is applied along at least part of said upper edge (18) of the inner wall (16) and is adapted to allow bonding the printed circuit board (2) to the first component (4) of the containment enclosure itself, and wherein said at least a first and second components (4, 5) are connected to each other by at least one waterproof joint (6).
Monopole antenna (100) according to claim 1, wherein said first and second components (4, 5) are soldered to each other.
Monopole antenna (100) according to claim 1 or 2, wherein said second component (5) comprises a first portion (5A) having a substantially planar development within which is housed at least a portion of the radiating element (1).
Monopole antenna (100) according to one or more of the previous claims, wherein said second component (5) of the containment enclosure comprises at least a second portion (5B) configured substantially in the form of a box open on one side and which includes a back wall (20) opposite the open side, one or more second side walls (22) which protrude transversally from the back wall (20) around an interior space (24) suitable for housing said printed circuit board (2).
Monopole antenna (100) according to claim 4, wherein said at least one waterproof joint (6) comprises or consists of a layer of glue that is applied along at least part of one of the top edge of the one or more first side walls (14) and the top edge of the one or more second side walls (22), and is adapted to allow bonding between said first and second components (4, 5).
Monopole antenna (100) according to one or more of the previous claims, further comprising an electrical contact (3) configured to electrically connect the radiating element (1) to the printed circuit board (2).
Monopole antenna (100) according to claim 6, wherein said electrical contact (3) comprises a shaped body having a first portion (3A) soldered to the printed circuit board (2) and a second portion (3B) adapted to couple with an associated portion of the radiating element (1).
Monopole antenna (100) according to claim 6 or 7, wherein said electrical contact (3) comprises a body configured to connect the printed circuit board (2) to the radiating element (1) in a structurally removable manner.
Monopole antenna (100) according to one or more of the preceding claims, wherein said radiating element (1) comprises a body having at least a first portion (1A) with a substantially planar development, and a tooth (1B) that protrudes transversally from the first portion (1A) and is configured to couple with an associated portion (3B) of the electrical contact (3).
Monopole antenna (100) according to one or more of the preceding claims, wherein said first component (4) of the containment enclosure is made at least in part of metallic material or an electrically conductive plastic material.
Motor vehicle characterized by comprising at least one monopole antenna (100) according to one or more of the previous claims.