WO2019229344A1

WO2019229344A1 - Motor vehicle door handle comprising ultra-high-frequency communication means

Info

Publication number: WO2019229344A1
Application number: PCT/FR2019/051220
Authority: WO
Inventors: Olivier Gerardiere; Grégory SIGUIER
Original assignee: Continental Automotive France; Continental Automotive Gmbh
Priority date: 2018-05-31
Filing date: 2019-05-27
Publication date: 2019-12-05
Also published as: FR3081903A1; FR3081903B1

Abstract

The invention relates to a motor vehicle (V) door handle (P', P'', P''') provided with an ultra-high-frequency antenna (A2) and emitting and receiving means of the antenna (300, 400), and a device (D') for detecting the approach and/or the contact of a user, comprising at least one approach-detecting and/or contact-detecting sensor (700, 700'), said handle (P', P'', P''') also comprising, on an outer face (Sext), a part (C) consisting of a conductive metal. According to the invention, the ultra-high-frequency antenna (A2) consists partially or entirely of the conductive metal part (C) which is connected to the emitting and receiving means (300, 400) by at least one electrical connection (200, 201).

Description

Vehicle door handle equipped with an ultra high frequency antenna

The invention relates to a door handle of a motor vehicle comprising ultra-high frequency communication means. More particularly, the invention applies to a door handle comprising communication means Bluetooth ® intended to communicate with a portable user equipment to allow free access to the vehicle, that is to say say locking and / or unlocking the door.

Nowadays, the vehicle door handles are equipped with devices for detecting the intention of locking or unlocking a vehicle door by a user. Detection of a user's locking / unlocking intention coupled with the recognition of an identifier included in a "hands-free" access device, for example a "hands-free" electronic badge for remote access control, or a mobile phone, worn by this user, allows remote locking and unlocking of the opening of the vehicle. Thus when the user, wearing the electronic badge or the corresponding phone and identified by the vehicle wishes to unlock the vehicle, it approaches the handle or touches the door handle of the vehicle and the opening of the vehicle is then automatically unlocked. By approaching or pressing a specific point on the vehicle's door handle, called the "unlocking zone", the door (or alternatively all the doors) is (are) unlocked (unlocked) without further action by the user . Conversely, when the user, always wearing the necessary badge and identified by the vehicle, wants to lock his vehicle, he closes the door of his vehicle and he approaches or momentarily presses on another specific place of the handle, called "zone locking. This action automatically locks the opening of the vehicle.

These detection devices generally comprise two capacitive sensors, in the form of two electrodes electrically connected to a printed circuit integrated in the door handle each in a specific area of locking or unlocking. Generally, an electrode is dedicated to each zone, that is to say an electrode is dedicated to the detection of the approach and / or the contact of the user's hand in the locking zone and an electrode is dedicated detection of the approach and / or contact of the user's hand in the unlocking area.

The locking / unlocking detection device further comprises a radio frequency antenna for exchanging an identifier between the vehicle and the free hand access badge or the telephone. This antenna can be of the low frequency type ("low frequency" or LF, in English), for example at 125 kHz.

In the case where the portable device is a mobile phone, communication with the vehicle in Radio Frequency and LF is not always possible, because most mobile phones do not have RF or LF communications means, whose frequencies are compatible with those used when communicating with a vehicle, such as the frequencies of 315 MHz and 433.92 MHz for the RF and 125 kHz for the LF.

However, mobile phones now have the Bluetooth® or Bluetooth Low Energy "BLE" communication standard, that is, Ultra High Frequency (UHF) communication from 2.4 GHz to 2.48 GHz. This communication standard has the advantage of being universal and therefore does not require country-specific certification (only an international Bluetooth Low Energy certification), as is the case with the current RF and LF communication standards of which operating frequency differs by country.

It is therefore necessary to adapt the "hands-free" access and / or start system to a vehicle so that it can also operate with a mobile phone equipped with the Bluetooth ® communication standard and no longer only via radio waves and low frequencies (RF, LF).

The advantage of the Bluetooth® communication standard or Bluetooth Low Energy BLE is that it allows a wide communication range of about 100 m around the vehicle for the BLE.

Bluetooth® communication therefore has many advantages over the low frequency.

The detection device is connected to the electronic computer of the vehicle (ECU: abbreviation for "Electronic Control Unit") and sends it a presence detection signal. The electronic computer of the vehicle has, beforehand, identified the user as being authorized to access this vehicle, or alternatively, following the reception of this presence detection signal, he carries out this identification.

As explained above, when the "hands-free" access device is a mobile phone, the exchange of identifier is done by Bluetooth® communication.

If the electronic computer recognizes the identification code as the one allowing access to the vehicle, it triggers the locking / unlocking of the door (or all the opening). If, on the other hand, the electronic computer has not received an identification code or if the identification code received is wrong, the locking or unlocking is not done. Such vehicles, therefore, are equipped with door handles comprising a detection device comprising itself a high frequency or ultra high frequency antenna (HF or UHF), and two electrodes connected to a microcontroller, integrated in a printed circuit and powered. in tension.

However, the integration of an Ultra High Frequency antenna in the handle has a major disadvantage.

A high-performance UHF antenna of planar type or called "patch" antenna, that is to say a plane antenna whose radiating element is a generally square or rectangular conductive surface can not be integrated into the handle. Indeed, the planar type ultra-high frequency antenna is larger than an LF antenna, and the handles already having many other electronic components, the remaining space allocated to the UHF antenna is often very small.

Instead, and for the sake of saving space, it is known to use an IFA type UHF antenna or an inverted F-millimeter antenna. This type of IFA UHF antenna is a monopole antenna grounded at one end and energized at an intermediate connection away from the ground connection. One of the advantages of this type of IFA UHF antenna is a more compact design than the planar UHF antenna. However, said IFA UHF antenna is less efficient than the planar UHF antenna, and generates a less homogeneous electromagnetic radiation having "black spots", that is to say zones of absence of radiation.

On the contrary, the planar UHF antenna generates directional and homogeneous electromagnetic radiation.

In addition, when the handle has on its outer surface, a conductive metal decorative element, such as a chrome strip, the presence of this metal material near the IFA UHF antenna disrupts its operation and further deteriorates the homogeneity of its electromagnetic radiation.

This is illustrated in Figure 1.

In Figure 1 is shown a door handle P of a motor vehicle V comprising a chrome strip C on its front face, facing outwardly of the vehicle V (see Figure 2).

The handle P comprises an approach and / or contact detection device D comprising an unlocking electrode E1 and a locking electrode E2.

The detection device D also comprises an Ultra High Frequency (UHF) antenna A of the IFA type.

The UHF antenna A, the locking electrode E1 and the unlocking electrode E2 are each electrically connected to control means, located by example in an electronic circuit 10, or PCB ("printed circuit board" in English), integrated circuit in French.

The electromagnetic Z radiation zone of the UHF antenna A around the handle P is inhomogeneous and has "holes". according to the three dimensions, illustrated by the axes XX ', YY', ZZ '(see Figure 2). This is illustrated in the section plane of the handle P along the longitudinal axis XX 'and the transverse axis YY' in FIG.

Reliable communication with the ultra-high frequency user portable equipment around the handle P is not assured.

In addition, the geometry of the conductive metal decorative element may vary according to the handle model, this therefore causes disturbances on the electromagnetic radiation of the IFA UHF antenna which are non-repeatable from one handle model to another .

It is understood that it is necessary to design for a door handle UHF communication means generating a homogeneous electromagnetic field around the handle, and this regardless of the handle model (having a conductive metal decoration element or not ).

For this purpose, the present invention proposes to overcome the problems of the prior art, by proposing a vehicle door handle comprising high performance ultra high frequency communication means, and overcoming the problem of lack of space in the handle to integrate said means.

The invention proposes a door handle of a motor vehicle, equipped with an ultra-high frequency antenna, and means for transmitting and receiving the antenna, an approach detection device and / or a contact device. a user, comprising at least one approach and / or contact detection sensors, said handle comprising on an outer face, a portion of conductive metal, the handle being remarkable in that the ultra-high frequency antenna is partly or totally consisting of the conductive metal portion connected to the transmitting and receiving means by at least one electrical connection.

In a second embodiment of the invention, the at least one approach detection sensor being a capacitive sensor comprising an electrode and capacitive detection means, the handle further comprises switching means and control means. said switching means adapted for;

In a first position: connect the transmitting and receiving means to the conductive metal part, when the sensor is in an inactive state, In a second position: connect the conductive metal part to a fixed potential, when the sensor is in an active state,

the control means being connected to the capacitive detection means and able to detect an active or inactive state of the sensor.

In a third embodiment of the invention, the at least one approach detection sensor being a capacitive sensor comprising an electrode and capacitive detection means, the handle further comprises a second connection permanently connecting the part conductive metal at a fixed potential.

Preferably, the handle is such that:

The electrical connection connects the transmitting and receiving means to the conductive metal part at a first junction point,

The second electrical connection connects the conductive metal portion to the fixed potential at a second junction point, the first junction point and the second junction point are on the same side of the conductive metal portion.

Advantageously, the first junction point is at one end of the conductive metal portion and the second junction point is at the same end of the conductive metal portion.

The invention also applies to any motor vehicle comprising a handle according to any one of the characteristics listed above.

Other objects, features and advantages of the invention will appear on reading the description which will follow by way of nonlimiting example and on examining the appended drawings in which:

FIG. 1 is a sectional view of a handle P comprising a detection device, according to the prior art and described previously,

FIG. 2 is a front view of a handle P comprising a chrome strip, explained previously,

- Figure 3 is a sectional view of a handle P ', P "illustrating a first and second embodiments of the handle according to the invention

- Figure 4 is a sectional view of a handle P ', P "illustrating the third embodiment of the handle according to the invention

FIG. 5 schematically represents the first embodiment of the control means of the new ultra-high frequency antenna according to the invention,

FIG. 6 diagrammatically represents the second embodiment of the control means of the new ultra high frequency antenna according to the invention, - Figure 7 shows schematically the third embodiment of the control means of the new ultra high frequency antenna according to the invention.

As explained above, a UHF antenna A in the form of an IFA antenna, integrated in a vehicle door handle P V, which has a portion of conductive metal C, for example a chrome decoration element, on a its faces, does not generate a homogeneous electromagnetic field around said handle P. Indeed, the presence of conductive metal disrupts the electromagnetic radiation produced by said antenna UHF A.

UHF, Ultra High Frequency, also means WiFi or other communication with a frequency greater than 3 GHz.

The invention provides a handle P ', P ", P'" overcoming the disadvantages of the prior art.

More specifically, the invention provides a handle P ', P ", P'" comprising an ultra high frequency antenna generating a homogeneous electromagnetic field around the handle P ', P ", P'". By homogeneous is meant an electromagnetic field propagating uniformly in the three directions XX ', YY', ZZ 'and not having a shadow zone, that is to say a zone of absence of radiation.

According to the invention, the handle P ', P ", P'" is equipped with a UHF antenna A2 and transmission and reception means 300, 400 connected to said UHF antenna A2 (see FIG. an approach and / or contact detection device D ', D ", D" including an approach and / or contact detection sensor 700.

The handle P ', P', P '"comprises on its outer faces Sext, a portion of conductive metal C (see Figure 2), for example a chrome decoration element. This element can be in the form of a chrome strip along the handle P ', P ", P'", or in the form of a chrome logo, a chrome insert or a metallic paint coating on the plastic surface of the handle P ', P ", P'".

The transmitting and receiving means 300, 400 comprise at least one transmitter / receiver 300 and means 400 for adapting the frequency of the UHF antenna A2, for example in the form of at least one capacitance and / or inductors.

The transmitting and receiving means 300, 400 are for example integrated in a printed circuit 100 (see FIG.

The approach detection sensor and / or contact 700 can be in the form of a capacitive sensor, or inductive or Hall effect.

In the example below and illustrated in FIGS. 3 to 7, the approach and / or contact detection sensor 700 is a capacitive sensor comprising an electrode E1 connected to capacitive detection means 500. The electrode E2 can be located on the printed circuit 101, 102 connected to the capacitive detection means 500 located in the printed circuit 101, 102.

The invention proposes that the UHF antenna A2 be partly or completely constituted by the conductive metal portion C.

For this purpose, and in a first embodiment of the invention, illustrated in Figures 3 and 5, the handle P 'further comprises an electrical connection 200 connecting the transmitting and receiving means 300, 400 to the part of conductive metal C.

The conductive metal part C therefore acts as a UHF antenna A2, since it is adapted to transmit and receive ultra-high frequency data via the transmitting and receiving means 300, 400. Electromagnetic radiation Z1 around the handle P 'is homogeneous (see Figure 3).

When the conductive metal part C is in the form of a chromium strip along the handle P ', P ", P'", said conductive metal part C can constitute, by itself, as such a UHF antenna A2.

When the conductive metal portion C is in the form of a logo or a chrome insert, that is to say a small portion of conducting metal C, located on the handle P ', said conductive metal portion C can only partially fulfill the role of a UHF antenna A2. In this case, an IFA-type complementary antenna can be envisaged in the handle P 'in order to complement the radiation pattern.

However, the use of the conductive metal portion C as the Ultra High Frequency Antenna A2 disrupts the operation of the capacitive sensor 700 'and acts as a shielding electrode. The sensitivity of approach and / or contact detection is strongly degraded, or detection is impossible.

In order not to disturb the operation of the capacitive sensor 700 ', when said sensor 700' is in an active state, that is to say when the capacitive detection means 500 detect the approach and / or the contact of a user on the handle P ", the invention provides in a second embodiment that the handle P" (this is illustrated in Figures 3 and 6) further comprises switching means S and control means 600 of said means S switching.

The switching means S may be in the form of a switch S (see FIG. 6), electrically connecting either the conductive metal portion C, to the transmitting and receiving means 300, 400, or to the ground.

Said switching means S are suitable for:

In a first position: connect the transmitting and receiving means 300, 400 to the conducting metal part C when the 700 'sensor is in an inactive state. In this first state, the conductive metal part C acts as a UHF antenna A2,

In a second position: connect the conductive metal part C to a fixed potential, preferably to the electrical ground, when the sensor 700 'is in an inactive state.

The active or inactive state of the sensor 700 'is provided by the capacitive detection means 500 connected to the sensor 700'.

The capacitive detection means 500 comprise, for example, a capacitance circuit, a voltage comparator, and software means, that is to say an electronic circuit making it possible to measure the variation of a capacitance with the approach of a hand. 'a user, this measurement of variation can be achieved by measuring a voltage change following transfer cycles between a variable capacity and a reference capacity, or by measuring a cycle time of charges and landfills. This is known to those skilled in the art and will not be detailed here. Thus, the measurement of voltage or of a cycle time of charges and discharges makes it possible, when said voltage or said duration is above or below a threshold, to detect the presence of a hand of a user near the handle P ".

When an approach / and / or contact detection is enabled by said capacitive detection means 500, a detection signal is sent to the control means 600 to switch the switching means S to the second position. Conversely, when the capacitive detection means 500 detect no approach (voltage value or charge transfer number lower or higher than a predetermined threshold), then no detection signal is sent to the control means 600 and the means switching S switch to the first position.

The switching means S are in the first default position as long as a detection signal by the control means of the switching means.

Thus the UHF antenna A2 constituted by the conductive metal portion C and the capacitive sensor 700 'can operate sequentially.

Similarly, the zone of electromagnetic radiation Z1 around the handle P "is homogeneous (see FIG.

In a third embodiment of the handle P '"according to the invention, and illustrated in FIGS. 4 and 7, the handle P'" further comprises the electrical connection 200 permanently connecting the conducting metal portion C to the means transmission and reception 400, of the first embodiment, a second electrical connection 201 connecting the conductive metal portion C to a fixed potential, preferably to the electrical ground.

The electrical connection 200 connects the transmitting and receiving means 300, 400 to the conductive metal portion C at a first junction point J1. This is illustrated in Figure 7.

The second electrical connection 201 connects the fixed potential to the conductive metal portion C at a second junction point J2. This is illustrated in Figure 7.

Preferably, the first junction point J1 and the second junction point J2 are located on one and the same side of the conductive metal part C, for example at an end EXT 1 (see FIG.

For example, the first junction point J1 is at a first end EXT1 (see FIGS. 4 and 7) of the conductive metal part C and the second junction point is at the same end EXT1 of the conductive metal part. C (see Figures 4 and 7).

By thus connecting the UHF antenna A2, consisting of the conducting metal part C at two distinct junction points J 1, J 2 to the transmitting and receiving means 300, 400 and at a fixed potential, said UHF antenna can continue to transmitting and receiving data in UHF while not affecting the operation of the capacitive sensor 700. The latter can operate and its detection sensitivity is not degraded. In this third embodiment, the capacitive sensor 700 and the UHF antenna A2 operate in parallel and in a continuous manner. Similarly, the electromagnetic radiation zone Z2 around the handle P '"is homogeneous (see FIG.

The invention therefore ingeniously allows the realization of a vehicle door handle incorporating a UHF antenna whose electromagnetic radiation is not impacted by metal parts on the handle. The invention judiciously proposes to use these metal parts as a UHF antenna. In addition, the invention also proposes a solution that overcomes the interference between an approach and / or contact detection sensor and the UHF antenna.

The invention is simple to produce, inexpensive and robust.

Claims

1. handle (P \ P ", P '") of a motor vehicle door (V), equipped with an ultra high frequency antenna (A2), and means for transmitting and receiving the antenna (300, 400), a user approach and / or contact detection device (D '), comprising at least one approach and / or contact detection sensors (700, 700'), said handle (P ', P ", P'") comprising on an outer face (Sext), a decorative metal decoration element (C), characterized in that the ultra-high frequency antenna (A2) is partly or wholly constituted the conductive metal decorative element (C) connected to the transmitting and receiving means (300, 400) by at least one electrical connection (200, 201).

2. Handle (P ") according to the preceding claim, characterized in that the at least one approach detection sensor (700 ') being a capacitive sensor comprising an electrode (E1) and capacitive detection means (500) the handle (P ") further comprises switching means (S) and control means (600) of said switching means (S) adapted for;

In a first position: connecting the transmitting and receiving means (300, 400) to the conductive metal decoration element (C), when the sensor (700 ') is in an inactive state,

In a second position: connect the conductive metal decorative element (C) to a fixed potential, when the sensor (700 ') is in the active state,

the control means (600) being connected to the capacitive detection means (500) and able to detect an active or inactive state of the sensor (700 ').

3. Handle (P '") according to claim 1, characterized in that the at least one approach sensing sensor (700) being a capacitive sensor comprising an electrode (E1) and capacitive sensing means (500) the handle (P '") further comprises a second connection (201) permanently connecting the conductive metal decorative element (C) to a fixed potential.

4. Handle (P '") according to the preceding claim, characterized in that:

The electrical connection (200) connects the transmitting and receiving means (330, 400) to the conductive metal decoration element (C) at a first junction point (J 1), The second electrical connection (201) connects the conductive metal decorative element (C) to the fixed potential at a second junction point (J2),

the first junction point (J 1) and the second junction point (J2) are on the same side (EXT 1) of the conductive metal decorative element (C).

5. Handle (P '") according to the preceding claim, characterized in that the first junction point (J 1) is at one end (EXT 1) of the conductive metal decorative element (C) and the second junction point (J2) is at the same first end (EXT1) of the conductive metal decorative element (C).

6. Motor vehicle (V) comprising a handle (P ', P ", P'") according to any one of the preceding claims.