EP2013432B1 - Device for the hands-free locking/unlocking of the opening parts of a vehicle - Google Patents

Description

The present invention relates to locking-unlocking devices of the opening of motor vehicles using so-called hands-free systems including badges. More particularly, the invention relates to means for transmitting signals intended for these badges.

The operation of the locking-unlocking devices of the opening of a vehicle today often uses so-called hands-free devices based on radio-based information exchanges between equipment on board the vehicle and electronic equipment, often called badge, worn by the user.

One of the particular modes of operation of such devices is the mode D said approach detection mode. This mode corresponds to a situation in which access to the vehicle is condemned, in the absence of a badge near the vehicle and wherein the onboard system seeks to detect whether a badge, worn by a user approaching the vehicle, enters into a proximity perimeter within which the presence of the badge can be detected. This is a mode in which the vehicle seeks to detect the approach of a badge.

In order to detect if a badge enters the proximity perimeter, the on-board equipment frequently transmits radio signals, generally in a low frequency range, called LF, in the 125 kHz range, which will be received by a badge, if the badge is in the near perimeter.

When the badge enters said proximity perimeter, it receives the radio signals LF emitted by the on-board equipment, and in turn transmits a radio signal, generally in a radio frequency domain, called RF, in the field of 433 MHz, to inform the embedded system of its presence in the proximity perimeter. Of course, for security reasons, the signals exchanged are coded to allow an exclusive exchange between an embedded system and an associated authorized badge.

When the RF signal of a badge is received by the onboard system, the device leaves the approach detection mode D.

In order to achieve this approach detection function as illustrated on the figure 1 , the on-board equipment implements signal transmission means, comprising external antennas 14a, 14b distributed over the vehicle to cover the proximity perimeter in which the LF signals must be received by a badge, amplification means 12a, 12b coupled to the antennas and control means 10.

In approach detection mode D, such a device emits periodic signals while waiting for a response from a hypothetical badge, an emission that induces an electrical consumption.

Such devices are known from for example DE-A-19832285 or US-2005/0237220 .

The known devices absorb a power of the order of 2W, at least partly because of the radiated power and because of bias currents related to the technology of the amplifiers used.

When the device remains in approach detection mode D for a long time, the battery essentially solicited by the device is progressively discharged. It is common to see that a vehicle equipped with such a device can not start on the battery if it remained in approach detection mode more than a few days.

The present invention proposes a solution for reducing the consumption of the on-board system in approach detection mode and thus increasing the time during which the battery is able to power the device and to allow the vehicle to start.

In order to reduce the power consumption and to increase the battery life of a vehicle comprising a device for unlocking and unlocking the vehicle doors, the device is equipped with amplification means, coupled to the antennas, which are specific to the vehicle. mode during which the device consumes the most energy because of its duration of operation.

• au moins un mode D de détection d'approche correspondant à une période de recherche de badge et un mode P de poursuite correspondant à une période pendant laquelle il n'y a pas de recherche de badge,
• une première antenne couplée à un premier amplificateur actif en mode P,
• au moins une seconde antenne couplée à au moins un second amplificateur actif en mode P,

As in a conventional device, said device comprises:

• at least one approach detection mode D corresponding to a badge search period and a tracking mode P corresponding to a period during which there is no search for a badge,
• a first antenna coupled to a first active amplifier in P mode,
• at least one second antenna coupled to at least one second active amplifier in P mode,

It furthermore comprises at least one amplifier, different from the first and second active amplifiers in the P mode, this amplifier being active in the D mode, coupled to the first antenna and to the second antenna in the D mode, this amplifier being inactive in the P mode, decoupled from said first and second P-mode antennas. In addition, the first and second P-mode active amplifiers are inactive, decoupled from the antennas, in the D mode.

In a preferred embodiment, means are provided for reducing or canceling the supply currents of at least one of the inactive amplifiers in the D mode. when said device operates in D mode, and advantageously means are arranged to reduce or cancel the power supply currents of the amplifier (s) inactive mode (s) when said device operates in P mode.

Advantageously, in order to reduce the consumption of the device in the D mode, the power consumed by the active amplifier in the D mode is less than the sum of the powers of the active amplifiers in the P mode. For example, the amplifiers of the device are chosen with substantially the same power. .

Control means, similar to those of the known devices, capable of determining whether a mode P or a mode D is active, generates control signals for the switching means associated with the power supplies of the amplifiers and switching means of the outputs amplifiers so that each amplifier is active or inactive depending on whether the device is in P mode or is in D mode.

In a particular embodiment, each antenna is a bipolar antenna, one pole of which is capable of being coupled to an active amplifier in the P mode and the other pole of which is capable of being coupled to an active amplifier in the D mode. the antenna coupled to said P mode active amplifier is grounded when said device is in D mode and the pole of the antenna coupled to said D mode active amplifier is grounded when said device is in P mode.

In another particular embodiment, each antenna comprises a point of connection to amplifiers, said connection point being connected to switching means comprising at least a first position in which the antenna is coupled to an active amplifier in P mode and at least a second position in which the antenna is coupled to an active amplifier in mode D.

• Figure 1 déjà citée, une vue schématique d'une partie d'un circuit électronique de commande d'antenne d'un véhicule d'un dispositif connu;
• Figure 2 une vue schématique d'un véhicule comportant un système embarqué suivant l'invention ;
• Figure 3 une vue schématique d'un exemple de moyen d'amplification utilisé dans l'invention, notamment pour un amplificateur actif en mode poursuite P ;
• Figure 4 une vue schématique d'une partie du circuit électronique de commande d'antenne dans la configuration du mode P, dit de poursuite ;
• Figure 5 une vue schématique d'une partie du circuit électronique de commande d'antenne dans la configuration du mode D, dit de détection d'approche.
• Figure 6 une vue schématique d'une partie du circuit électronique de commande d'antenne selon une autre forme de réalisation de l'invention.

The detailed description of the device is made with reference to the figures which represent:

• Figure 1 already cited, a schematic view of a portion of an antenna control circuit of a vehicle of a known device;
• Figure 2 a schematic view of a vehicle comprising an embedded system according to the invention;
• Figure 3 a schematic view of an example of amplification means used in the invention, in particular for an active amplifier in P tracking mode;
• Figure 4 a schematic view of a portion of the antenna control electronics circuit in the P mode configuration, said tracking;
• Figure 5 a schematic view of a portion of the antenna control electronics in the mode configuration D, said approach detection.
• Figure 6 a schematic view of a portion of the antenna control electronics according to another embodiment of the invention.

A device according to the invention for locking and unlocking the doors of a vehicle 1 ( figure 2 ) has an embedded system 4 capable of transmitting signals 5 to be received by a badge 2, when said badge is in a perimeter 3 around the vehicle, said perimeter of proximity. Said device also comprises at least two modes of operation: a first mode called approach detection mode or mode D, in which no badge is identified by the onboard system and wherein the device seeks to detect whether a badge enters into the proximity perimeter, and a second mode called tracking mode or P mode, active when a badge has been detected by the onboard system within the proximity perimeter.

• des moyens d'émission de signaux radioélectriques comportant :
• une première antenne 14a apte à être couplée à un premier amplificateur 12a ;
• au moins une seconde antenne 14b apte à être couplée à au moins un second amplificateur 12b ;
• des moyens de commande 10 qui génèrent des signaux 15a, 15b, destinés à être amplifiés par lesdits premier et seconds amplificateurs et émis par les antennes, et qui sont aptes à commander les configurations desdits amplificateurs dans les différents modes de fonctionnement comme il sera détaillé plus loin.

The embedded system 4 comprises in particular, as illustrated on the figure 2 :

• means for transmitting radio signals comprising:
• a first antenna 14a adapted to be coupled to a first amplifier 12a;
• at least a second antenna 14b adapted to be coupled to at least a second amplifier 12b;
• control means 10 which generate signals 15a, 15b, intended to be amplified by said first and second amplifiers and emitted by the antennas, and which are able to control the configurations of said amplifiers in the different operating modes as will be detailed more far.

The first and second amplifiers 12a, 12b are also called P-mode amplifiers and are powered by at least one voltage source 24, in general the vehicle battery.

The onboard system 4 further comprises at least one amplifier 12c, said amplifier in mode D, distinct from the first and second amplifiers 12a, 12b in P mode, able to be coupled simultaneously to the first antenna 14a and the second antenna 14b, globally. designated by the antennas.

The control means 10 generate signals 15c intended to be amplified by the amplifier 12c in the D mode and transmitted by the antennas 14a, 14b. Said control means are also able to control the configuration of said amplifier in mode D according to the mode in which the device operates. The amplifier 12c in the D mode is also powered by the voltage source 24.

In a particular embodiment, the antennas are bipolar antennas, one pole of which is connected to the output of the amplifier which supplies the amplified signal intended to be radiated by said antenna and whose other pole is connected to a mass which is also the mass of the amplifier.

The antennas 14a, 14b are arranged on the vehicle 1 in such a way that they radiate the radio signals 5 in the proximity perimeter 3. For example, the first antenna is located on one side of the vehicle, for example the driver's side, and the second antenna is located on another side of the vehicle, for example the passenger side.

The known devices most often use low-frequency radio signals known as LF in the 125 kHz range, as in the embodiment described, but the invention is not limited to this frequency range.

The figure 3 schematically discloses an amplification means 18 implemented by the device according to the invention, in particular for a P-mode amplifier. This diagram is also applicable to a D-mode amplifier. The amplification means 18 comprises a similar amplifier 12 to those used in conventional devices and switching means 162, schematized in the figures by a switch, which allow either to connect the output 17 of the amplification means 18 to the output of the amplifier 12, or to connect said output amplification means to ground. Said amplification means also comprise switching means 161, represented on the figure 3 by a switch symbol having an open position and a closed position, which act on the supply of the amplifier 12. Said switching means 161, 162 are controlled by signals received by the amplification means. The switching means 161 associated with the power supply of the amplifier comprise a position in which the consumption of the amplifier is reduced or canceled, in particular in order to reduce, when the amplifier is not used, the power consumed. by the amplifier related to the existence of a bias current.

An amplifier 12 is said to be active when it is coupled to the antenna and sends the amplified signal to the antenna, that is to say that the switching means 162 connect the output 17 of the amplification means to the output of the amplifier 12 and that the switching means 161 are in a condition which provides the power supply of the amplifier 12. Otherwise the amplifier is said to be inactive.

In a first mode of operation of the device, said tracking mode or P mode, whose configuration is shown schematically on the figure 4 , switching means 162c are controlled so that the output of an amplification means 18c, comprising the amplifier 12c in D mode, is connected to ground. The poles of the antennas 14a 14b capable of being coupled to the amplifier in the D mode are then connected to ground. Switching means 162a, 162b of amplification means, respectively 18a, 18b, comprising the P-mode amplifiers, respectively 12a, 12b, are controlled so that said amplifiers 12a, 12b are connected to their antennas 14a, 14b for transmitting the signals 15a, 15b sent by the control means 10 to the inputs of said amplifiers in P mode. The switching means 161a, 161b, 162a, 162b, amplification means 18a, 18b are controlled so that the amplifiers 12a, 12b in P mode are active and advantageously, the switching means 161c inhibit the power supply of the amplifier 12c in D mode, inactive. In the tracking mode P, each antenna 14a, 14b emits a signal of its own and the power of which, depending on the characteristics of the amplifier associated therewith, may be different for each antenna if necessary.

This configuration of the device used in the P mode is activated by the control means 10, especially when the presence of the badge 2 in the proximity perimeter 3 has been detected and that the badge is supposed to be still in this perimeter.

In a second mode of operation of the device, said approach detection mode or mode D, whose configuration is presented on the figure 5 , the switching means 162c of the amplification means 18c are controlled so that the output of said amplification means comprising the amplifier 12c in the D mode, and therefore the antennas 14a, 14b, are coupled to said amplifier in the D mode and the means a switching means 162a, 162b of amplification means, respectively 18a, 18b, are controlled so that the output of each amplification means 18a, 18b, and therefore each of the antenna poles adapted to be coupled to a mode amplifier P, is connected to the mass. The switching means 161c of the amplifier 12c in the D mode are controlled so that said amplifier in the D mode is active and advantageously the switching means 161a, 161b associated with the amplifiers respectively 12a, 12b in the P mode are controlled so that the currents d supply of said amplifiers in P mode are reduced or canceled, for example by inhibiting their power supply by the battery 24. In the approach detection mode D, the two antennas 14a, 14b emit the same signal 15c amplified by the amplifier 12c in D mode and whose total radiated output power is a function of the characteristics of said amplifier.

This configuration of the device is used in the mode D, ie when no badge 2 is identified (or supposed to be in the detection perimeter 3) and a periodic signal 5 must be transmitted by the onboard system to be received by a badge that would enter said detection perimeter.

In another embodiment of the invention, presented on the figure 6 , switching means 163a, 163b are arranged such that the pole of the antenna coupled to an amplifier P mode 12a, 12b which is coupled to the antenna, respectively 14a, 14b, when the device operates in the P mode be decoupled from the output of the amplifier in P mode and coupled to the output of an amplifier 12c in D mode when the device is operating in the D mode.

According to the invention, when the approach detection mode D is active, a single amplifier is used to which the antennas 14a, 14b are coupled and radiate the signal 5. The radiation pattern of all the antennas and the perimeter of 3, are substantially identical to those obtained with the known devices, and the badge 2 receives mode D the transmitted signal, regardless of the path followed to arrive in the detection perimeter 3, no significant difference compared to a device using the same amplification and transmission means for the D mode and the P mode.

Advantageously, the currents of the power supplies, in particular the bias currents, of the amplifiers 12a, 12b in the P mode are canceled by the switching means 161a, 161b when the device is operating in D mode so that said amplifiers in P mode, unused in the mode D, do not consume more energy.

By the choice of a D-mode amplifier whose power consumption is less than the sum of the powers of the amplifiers in P mode and by canceling the polarization currents of the amplifiers in P mode when said amplifiers in P mode are not active, the Device consumption in D mode is significantly reduced.

The use of a D-mode amplifier which is less powerful than the sum of the output powers of the amplifiers in the P mode has the consequence of reducing the dimensions of the detection zone, but in practice, taking into account the conditions specific to this type of amplifier. devices using LF frequencies, dividing the amplification power by two only reduces the detection distance by around 10%. Thus there is no inconvenience unacceptable operationally compared to a situation in which it is impossible to start the vehicle because the battery is discharged.

Advantageously, the amplifiers in the P mode and the amplifier in the D mode are chosen to be identical.

When the device operates in P mode, the bias current of the amplifier 12c in D mode is advantageously canceled by the switching means 161c to reduce the consumption of the device.

However, in a simplified embodiment of the device, the bias current of the amplifier 12c in the D mode is not reduced or canceled because of the limited benefit in terms of power consumption brought by the cancellation of the bias current . Indeed, the power consumption of the device is not critical in P mode because either the presence of the badge 2 near the vehicle 1 corresponds to an imminent start and therefore to a charging period for the battery 24, or the presence the badge near the vehicle is temporary and the D mode will be activated again as soon as the badge is no longer in the proximity perimeter 3.

The switching means 161a, 161b, 161c, 163a, 163b are controlled by the control means 10 which generate control signals adapted to the structure of said switching means. These switching means are for example micro-relays or static switches whose technologies are known. Of course these switching means could be replaced by any other equivalent means.

The existing control means, generally based on microprocessors, already know at least two modes of operation corresponding to mode P and mode D which are not specific to the present invention. The generation of the signals that must be received by the amplifiers and the switching means according to the mode of operation therefore presents no particular difficulty and is not described.

The described device comprises two antennas 14a, 14b, for example an antenna corresponding to a detection coverage area on the driver's side of the vehicle and an antenna corresponding to a detection coverage area on the passenger side of the vehicle.

The device may also comprise other antennas, for example a front antenna and / or a rear antenna, each coupled to a mode P amplifier that is specific to it. A P-mode amplifier can also be coupled to two or more antennas.

The present invention therefore consists in using additional amplification means and an additional control device for connecting the external antennas to the same amplification means simultaneously in the D mode, and to separate amplification means in other modes ( P mode).

In such cases, all of the antennas are advantageously coupled to a single amplifier in the D mode. An antenna coupler at the output of the amplifier in the D mode distributes, if appropriate, the power between the different antennas.

Claims (8)

1. Device (4) for locking/unlocking doors/windows of a vehicle (1), said device comprising:

   - at least an approach-detection mode D and a tracking mode P;

   - a first antenna (14a) coupled to a first amplifier (12a) that is active in mode P;

   - at least a second antenna (14b) coupled to at least a second amplifier (12b) that is active in mode P;

   characterised in that it comprises at least one amplifier (12c) different from the first and second amplifiers (12a, 12b) that are active in mode P, said amplifier (12c) being active, coupled to the first antenna (14a) and to the second antenna (14b), in mode D, said amplifier (12c) being inactive, decoupled from said first antenna and from said second antenna, in mode P, and in that the first and second amplifiers (12a, 12b) that are active in mode P are inactive, decoupled from the first and second antennae (14a, 14b), in mode D.
2. Device according to claim 1, comprising means (161a, 161b) to reduce or cancel the power supply currents for at least one of the amplifiers (12a, 12b) that are inactive in mode D when said device is operating in mode D.
3. Device according to claim 2, comprising means (161c) to reduce or cancel the power supply currents of the amplifier(s) that are inactive in mode P when said device is operating in mode P.
4. Device according to one of the preceding claims, wherein the power consumed by the amplifier (12c) that is active in mode D is less than the sum of the powers of the amplifiers (12a, 12b) that are active in mode P.
5. Device according to claim 4, wherein the output power of the amplifier (12c) that is active in mode D and the output powers of the first and second amplifiers (12a, 12b) that are active in mode P are approximately the same.
6. Device according to one of the preceding claims, wherein a control means (10), able to determine whether a mode P or whether a mode D is active, generates control signals intended for the switching means (161a, 161b, 161c) associated with the power supplies of the amplifiers and with the switching means (162a, 162b, 162c, 163a, 163c) of the outputs of the amplifiers in order that each amplifier is active or inactive according to whether the device is in mode P or is in mode D.
7. Device according to one of the preceding claims, wherein each antenna (14a, 14b) is a bipolar antenna, one pole of which is able to be coupled to an amplifier (12a, 12b) that is active in mode P and the other pole of which is able to be coupled to at least one amplifier (12c) that is active in mode D, the pole of the antenna coupled to said amplifier that is active in mode P being coupled to ground when said device is in mode D and the pole of the antenna connected to said amplifier that is active in mode D being connected to ground when said device is in mode P.
8. Device according to one of claims 1 to 6, wherein each antenna (14a, 14b) comprises an amplifier connection point, said connection point being connected to switching means (163a, 163b) comprising at least a first position in which the antenna is coupled to an amplifier (12a, 12b) that is active in mode P and at least a second position in which the antenna is coupled to at least one amplifier (12c) that is active in mode D.

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