EP3813206A1 - Connection assembly for a passive security device, protected against electrostatic discharges - Google Patents

Abstract

Motor vehicle safety device igniter connection assembly. This connection assembly includes an igniter connector and an airbag connector. The igniter connector has two male contacts and one ground contact. The airbag connector comprises a housing in which are housed two female contacts (12) electrically connected each respectively to a male contact of the igniter connector, as well as at least a third contact (20) for connection to ground, via the ground contact of the igniter connector. At least one capacitive or resistive electronic component (18) is connected between, on the one hand, the grounding circuit comprising the grounding contact of the igniter connector and, on the other hand, one male contacts or one of the female contacts (12).

Description

Technical area

The invention relates to the field of automotive connectors and more particularly to the field of connectors for a passive safety device for a motor vehicle of the airbag type, seat belt pretensioner, etc. also called “SRS” devices, from the acronym for “Safety Retraint Systems”.

State of the art

In this field, the passive safety devices can include igniters ("squibs" in English) gas generators whose ignition is electronic. In this case, the igniter comprises an igniter connector ("squib connector" in English), itself coupled to a connector, called "airbag connector" ("airbag connector" in English). Throughout this document, the term “airbag connector” is used generically to refer to a connector connected, via electrical wires, to a triggering control device of an igniter, and this whether the igniter is an igniter intended to be ignited. inflate an airbag, pretend a seat belt, or the like.

When an impact exceeds a fixed deceleration or acceleration threshold, the igniter is triggered by the programmed control device to send a signal to the igniter to which it is connected, via electrical wires and an airbag connector. The resulting explosion generates sudden combustion which induces a high gas pressure in a piston (pretensioner) or an inflatable bag (airbag).

It is important to ensure that the igniters do not go off without being the consequence of an appropriate command. In order to avoid untimely tripping, it has already been proposed to filter, for example with ferrites, electrical signals transmitted by the electrical wires connected to an igniter and which would not be generated by the control device, but by electromagnetic interference. Electromagnetic disturbances are in fact generated over frequency ranges which are generally well filtered by ferrites placed in an airbag connector connected to the electric wires and coupled to the connector of the igniter.

For example, we can refer to the document EP1009070A2 for a description of such a connector.

We also know from documents WO2012014072A1 and US5435754A1 , airbag connectors with a component interposed between the signal contacts to filter electromagnetic interference (this type of filtering should not be confused with protection against electrostatic discharge).

However, it could also happen that an igniter is also triggered under the effect of an electrostatic discharge, in particular when the airbag connector is mated to the connector of the igniter. In order to avoid this, it has been proposed to equip the airbag connectors with a device which bypasses the contacts of the airbag connector as long as the latter is not mated to the connector of the igniter and which opens during mating of these connectors. For example, we can refer to the document EP3116075A1 for a description of such a connector.

A further contribution to the improvement of the protection against possible electrostatic discharges, of the connection assemblies for passive safety devices as mentioned above is proposed below.

Summary of the invention

More particularly, there is proposed a connection assembly for a passive safety device of a motor vehicle. This assembly comprises on the one hand, an igniter connector housed in an electrically conductive metallic igniter body and connected to the ground of the vehicle and, on the other hand, a counter-connector coupled to the igniter connector.

In this assembly, the igniter connector includes two igniter contacts electrically connected to the igniter and a ground contact electrically connected to the ground of the vehicle.

In this assembly, the counter-connector comprises a housing in which are housed a first and a second electrically coupled contacts each respectively to a contact of the igniter connector, as well as a third contact in contact with the ground contact of the connector. igniter.

The third contact and the ignition connector ground contact are included in a ground circuit.

In addition, at least one dissipative, capacitive or resistive electronic component is placed, for example in series, in the grounding circuit and in electrical contact with one of the contacts included in the list made up of the ignition contacts. and first and second contacts.

Thus, any electrical charges generated, for example, by electrostatic effect in the wires connecting the control device to the airbag connector can be transmitted to the igniter body, itself connected to ground, via the igniter ground contact or through the third contact and the igniter ground contact. They are therefore evacuated without accumulating and without the risk of triggering the igniter during a discharge.

This connection assembly also optionally includes one and / or other of the following characteristics, each considered independently of one another or in combination of one or more others:

- the electronic component is a component for surface mounting;

• le composant électronique est monté entre deux lames élastiquement déformables.

- the electronic component is a resistor whose resistance is between 100kOhms and 10 GOhms; alternatively, an electronic component is used consisting of a capacitor whose capacitance is greater than or equal to 10nFarads:

• the electronic component is mounted between two elastically deformable blades.

According to another aspect, there is proposed a connector for a passive safety device, and more precisely an airbag connector. This connector comprises a housing in which are housed a first and second contact, as well as a third contact for grounding the vehicle. In addition, at least one capacitive or resistive electronic component is connected in series in a portion of an electrical circuit comprising, on the one hand, one of the first and second contacts and, on the other hand, the third contact.

This connector also optionally has a cover and the component is wedged (sandwiched) between the housing and the cover.

According to yet another aspect, there is proposed an igniter connector for a passive safety device of a motor vehicle, comprising two igniter contacts electrically connected to the igniter and a ground contact electrically connected to the ground of the vehicle. In addition, in this igniter connector, at least one capacitive or resistive electronic component is connected in series in an electrical circuit portion comprising, on the one hand, one of the igniter contacts and, on the other hand, the ground contact.

• on fournit un inflammateur comprenant un connecteur d'inflammateur comprenant deux contacts d'inflammateur et un contact de masse relié à la masse du véhicule ;
• on fournit un contre-connecteur comprenant un boîtier dans lequel sont logés un premier et un deuxième contacts, ainsi qu'un troisième contact (20),
• on connecte un composant électronique capacitif ou résistif entre, d'une part, au moins l'un des contacts compris dans la liste constituée des contacts d'inflammateur et des premier et deuxième contacts et, d'autre part, un circuit de mise à la masse comprenant le contact de mise à la masse du connecteur d'inflammateur et le troisième contact.

According to yet another aspect there is proposed a method of mounting a connection assembly for a motor vehicle safety device, in which

• an igniter is provided comprising an igniter connector comprising two igniter contacts and a ground contact connected to the ground of the vehicle;
• a counter-connector is provided comprising a housing in which are housed a first and a second contact, as well as a third contact (20),
• a capacitive or resistive electronic component is connected between, on the one hand, at least one of the contacts included in the list made up of igniter contacts and the first and second contacts and, on the other hand, a grounding circuit comprising the igniter connector grounding contact and the third contact.

Brief description of the drawings

• [Fig. 1] représente schématiquement en perspective un exemple de mode de réalisation d'un ensemble de connexion ;
• [Fig. 2] représente schématiquement en vue de dessus, sans son couvercle, un exemple de mode de réalisation d'un connecteur d'airbag pour l'ensemble de connexion illustré par la figure 1 ; cette figure montre notamment un premier et
• un deuxième contacts de signal traversant un bloc de ferrite, ainsi qu'un troisième contact formant un contact de masse ;
• [Fig. 3] représente schématiquement en coupe longitudinale la portion d'accouplement du connecteur d'airbag illustré par la figure 2 ;
• [Fig. 4] est une représentation schématique en perspective du montage d'un composant électronique entre un contact de signal et le troisième contact du connecteur d'airbag illustré sur les figures 1 à 3 ;
• [Fig. 5] est une représentation schématique d'un exemple de mode de réalisation d'une douille, vue de dessus, pour connecteur d'inflammateur pour l'ensemble de connexion illustré par la figure 1 ;
• [Fig. 6] est une représentation schématique en coupe de la douille pour connecteur d'inflammateur illustrée sur la figure 5 ;
• [Fig. 7] est une représentation schématique en perspective du montage d'un composant électronique entre un contact de signal et le contact de masse du connecteur d'inflammateur dont la douille est illustrée sur les figures 5 et 6.

Other characteristics, aims and advantages of the connection assembly mentioned above will become apparent on reading the detailed description which follows, and with reference to the appended drawings, given by way of non-limiting examples and in which:

• [ Fig. 1 ] schematically shows in perspective an exemplary embodiment of a connection assembly;
• [ Fig. 2 ] schematically shows a top view, without its cover, an exemplary embodiment of an airbag connector for the connection assembly illustrated by figure 1 ; this figure shows in particular a first and
• a second signal contact passing through a block of ferrite, as well as a third contact forming a ground contact;
• [ Fig. 3 ] shows schematically in longitudinal section the coupling portion of the airbag connector illustrated by figure 2 ;
• [ Fig. 4 ] is a schematic perspective representation of the mounting of an electronic component between a signal contact and the third contact of the airbag connector shown in figures 1 to 3 ;
• [ Fig. 5 ] is a schematic representation of an exemplary embodiment of a socket, viewed from above, for an igniter connector for the connection assembly illustrated by FIG. figure 1 ;
• [ Fig. 6 ] is a cross-sectional schematic representation of the igniter connector socket shown in Figure figure 5 ;
• [ Fig. 7 ] is a schematic representation in perspective of the assembly of an electronic component between a signal contact and the earth contact of the igniter connector, the socket of which is illustrated on the diagrams. figures 5 and 6 .

detailed description

An exemplary embodiment of a connection assembly 1 for a motor vehicle passive safety device is described below.

According to this embodiment, the connection assembly 1 comprises an igniter connector 2 and an airbag connector 3 forming a counter-connector.

The igniter connector 2 comprises a socket 4 housed in a cavity of a metallic igniter body 5 and connected to the ground of the vehicle, as well as two signal contacts 23 (not visible on the figure 1 ) igniter connector for the transmission of a signal (for example the signal triggering the igniter). These two contacts 23 are male contacts each comprising a pin (see figures 5 and 7 ) housed in a cavity 7 formed in the socket 4. In this embodiment, each of the male contacts 23 is electrically isolated from the socket 4.

As shown on the figure 1 , the airbag connector 3 comprises a housing 8, a cover 9, a device for ensuring the position of the connectors 10 (“CPA” or “connector position assurance”).

As shown on the figure 2 , the airbag connector 3 further comprises a ferrite block 11, as well as a first and a second female signal contact 12 adapted to each couple respectively with a male contact 23 of the igniter connector 2. The connector airbag 3 also includes a third contact 20. The first and second contacts 12 are each electrically connected to a control circuit, via electric wires 13.

The first, second 12 and third 20 contacts are each respectively made of a conductive metal strip, cut from a metal sheet, then folded and / or rolled. Each of the first, second 12 and third 20 contacts consists of a single piece (see also figure 4 ).

The first and second contacts 12 of the airbag connector 3 each comprise a contact portion 14 for establishing electrical contact with a contact of the igniter connector 2, a fixing portion 15 for fixing (for example by soldering) an electric wire 13 and establish an electrical connection with the control circuit.

The first and second contacts 12 of the airbag connector 3 each also include a short-circuit contact 16. The short-circuit contacts 16 of the first and second contacts 12 are in electrical contact with each other as long as the airbag connector 3 is not mated to the igniter connector 2. They thus establish a short circuit. This short circuit is opened when mating the airbag connector 3 and the igniter connector 2.

According to a first exemplary embodiment (illustrated in the figures 2 to 4 ), an electronic component 18 is housed in the airbag connector 3. In this case, one of the first and second contacts 12 of the airbag connector 3 comprises an elastic blade 17. The elastic blade 17 makes electrical contact with it. an electronic component 18 adapted to prevent the accumulation of electrostatic charges at the level of the first and second contacts 12. The electronic component 18 is, for example, a resistor whose resistance value is between 100 kOhms and 10 GOhms. Alternatively, it is, for example, a capacitor whose capacitance value is greater than or equal to 10 nFarads. For example, electronic component 18 is a surface mount component. It comprises two conductive terminals 19 and the elastic strip 17 establishes an electrical contact by pressure with one of these two terminals 19. The other terminal 19 is in electrical contact by pressure with the third contact 20. To this end, the third contact 20 comprises a folded portion 21 to form a spring resting on one of the terminals 19 of the electronic component 18. The electronic component 18 is therefore held sandwiched between two elastic tabs (the elastic blade 17 and the folded portion 21) which establish an electrical connection with each of its two terminals 19. As shown in figure figure 3 , the electronic component 18 is also sandwiched between the housing 8 and the cover 9.

According to a second exemplary embodiment (illustrated in the figures 5 to 7 ), an electronic component 18 is housed in the igniter connector 2.

One of the two male contacts 23 of the igniter connector 2 comprises, in addition to its pin, a conductive intermediate part 22, interposed between the pin and an electronic component 18. The part intermediate 22 is formed of a sheet wound around a longitudinal axis coinciding with the longitudinal axis of the spindle. Thus, the intermediate part 22 forms an incomplete cylindrical wall (it is not completely closed around its longitudinal axis) which lines part of a cavity 7. The intermediate part 22 comprises two elastic contact tabs 24 forming a spring in support, for one on the pin and for the other on a conductive terminal 19 of the electronic component 18. Furthermore, the other terminal 19 of the electronic component is in electrical contact with a third contact or ground contact 25 (also named “metal clip” or “shorting clip”) electrically intended to be connected to the ground of the vehicle by means of the metallic body 5 of the igniter. This ground contact 25 comprises an elastic tab 26 intended to establish contact with the third contact 20 of the airbag connector 3 and another elastic tab 27 intended to establish contact with a terminal 19 of the electronic component 18.

Thus, any electrical charges generated by an electrostatic effect, in default or in excess on at least one of the first and second contacts 12, are evacuated by the elastic blade 17, then via the third contact 20, towards the ground of the vehicle. These provisions protect the igniter and prevent it from triggering due to an electrostatic discharge, since the electric charges cannot accumulate sufficiently to create a sufficient potential difference, in particular between the contacts of the igniter connector 2. .

A first exemplary embodiment of a connection assembly 1 has been described above in which the electronic component 18 is housed in the airbag connector 3; a second exemplary embodiment of a connection assembly 1 has been described above in which the electronic component 18 is housed in the igniter connector 2; according to a variant of one or the other of these modes embodiment, an electronic component 18 can be housed in the two connectors 2, 3.

• on fournit un inflammateur comprenant un contact de masse 25 électriquement relié à un corps d'inflammateur 5 électriquement conducteur et relié à la masse du véhicule ;
• on fournit un contre-connecteur 3 comprenant un boîtier 8 dans lequel sont logés, un premier et un deuxième contacts 12, ainsi qu'un troisième contact 20, et éventuellement un bloc de ferrite 11 ;
• on place au moins un composant électronique 18 dans le circuit électrique de mise à la masse comprenant le contact de masse 25 et le troisième contact 20 ; et
• on relie les premier et deuxième contacts 12 à la masse du véhicule, par l'intermédiaire du contact de masse 25 de l'inflammateur, du composant électronique 18 et du troisième contact 20.

For mounting a connection assembly 1 according to one of the embodiments described above or their variants,

• providing an igniter comprising a ground contact 25 electrically connected to an electrically conductive igniter body 5 and connected to the ground of the vehicle;
• a counter-connector 3 is provided comprising a housing 8 in which are housed a first and a second contact 12, as well as a third contact 20, and optionally a ferrite block 11;
• at least one electronic component 18 is placed in the electrical grounding circuit comprising the ground contact 25 and the third contact 20; and
• the first and second contacts 12 are connected to the ground of the vehicle, by means of the ground contact 25 of the igniter, of the electronic component 18 and of the third contact 20.

Claims (9)

Connection assembly (1) for a passive safety device of a motor vehicle, comprising on the one hand, an igniter connector (2) housed in an electrically conductive metallic igniter body (5) and connected to the ground of the vehicle and , on the other hand, a mating connector (3) coupled to the igniter connector (2), in which: - the igniter connector (2) comprises two igniter contacts electrically connected to the igniter and a ground contact (25) electrically connected to the ground of the vehicle, - the counter-connector (3) comprises a housing (8) in which are housed a first and a second contact (12) electrically each respectively coupled to a contact of the igniter connector (2), as well as a third contact (20) in contact with the ground contact (25) of the igniter connector (2), the third contact (20) and the ground contact (25) of the igniter connector (2) being included in a circuit of earthing, characterized in that at least one dissipative electronic component (18) is placed in the earthing circuit and in electrical contact with only one of the contacts included in the list consisting of the contacts of igniter (23) and first and second contacts (12). An assembly according to claim 1, wherein the electronic component (18) is a surface mount component. Assembly according to claim 1 or 2, in which the electronic component (18) is a resistor whose resistance value is between 100kOhms and 10 GOhms. Assembly according to Claim 1 or 2, in which the electronic component (18) is a capacitor whose capacitance value is greater than or equal to 10 nFarads. Assembly according to one of the preceding claims, in which the electronic component (18) is mounted between two elastically deformable blades (17 and 21, 24 and 27). Connector for a passive safety device for a motor vehicle, comprising a housing (8) in which are housed a first and second contacts (12), as well as a third contact (20) for grounding the vehicle,
characterized in that at least one capacitive or resistive electronic component (18) is connected in series in a portion of an electrical circuit comprising, on the one hand, only one of the first and second contacts (12) and, of on the other hand, the third contact (20). A connector according to claim 6, wherein the connector (3) further comprises a cover (9) and the electronic component (18) is wedged between the housing (8) and the cover (9). Igniter connector (2) for a passive safety device of a motor vehicle, comprising two ignition contacts (23) electrically connected to the igniter and a ground contact (25) electrically connected to the ground of the vehicle, characterized by the causes that at least one capacitive or resistive electronic component (18) is connected in series in a portion of an electrical circuit comprising, on the one hand, only one of the ignition contacts (23) and, on the other hand, the earth contact (25). A method of mounting a connection assembly (1) for a motor vehicle safety device, in which - An igniter is provided comprising an igniter connector (2) comprising two igniter contacts (23) and a ground contact (25) connected to the ground of the vehicle; - A counter-connector (3) is provided comprising a housing (8) in which are housed a first and a second contact (12), as well as a third contact (20),
characterized in that at least one capacitive or resistive electronic component (18) is connected between, on the one hand, one of the contacts included in the list consisting of the ignition contacts (23) and the first and second contacts (12) and, on the other hand, a grounding circuit comprising the ground contact (25) of the igniter connector (2) and the third contact (20).

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