Distributed ground connection of a device connected to data exchange cables

Abstract

The invention relates to the connection to ground of a centralized electronic management device (51) of at least a first (9) and a second (13) electronic component, the two components exchanging data with the management device and the management device comprising an electrical circuit for connection to ground linked to the vehicle body and ensuring the connection to ground of the management device to which the two electronic components are connected. FIG. 3

Description

Title of the invention: Distributed ground connection of a device connected to data exchange cables

[0001] The present invention relates to the field of electrical management of the electronics of a land motor vehicle. In particular, it relates to a redundant ground connection of a centralized electronic management device for at least a first and a second electronic component, the device exchanging data with the components via cables specifically configured for data exchange.

[0002] The term “motorized land vehicle” means any type of vehicle such as a motor vehicle, a moped, an airplane, a train, a motorcycle, a warehouse storage robot, etc.

[0003] Internal vehicle networks now rely on a significant number of cables dedicated to high-speed data transmission. These cables, such as Ethernet cables or LVDS (Low Voltage Differential Signaling) cables, are configured for high-speed data transmission and therefore have specific shielding not suitable for high currents (greater than 3 Amperes).

[0004] This is illustrated by [Fig. 1], which schematically represents a part of the motor vehicle comprising the centralized electronic management device 51, here called IVI for In-Vehicle Infotainment, connected to a plurality of electronic components, and for example to: - a connectivity box 9, BSRF for radio frequency servicing box, connected to the device 51 by an Ethernet cable 7 having a shield 1 and connected to ground 10; - a Head-Up Vision unit, HUD 13, connected to device 51 by an LVDS HSD Ethernet cable, high speed data, 11 having shielding 4 and connected to ground 12; - a display management component 15 connected by an LVDS HSD cable 19 to the device 51; and - a handset management component 17 connected by an LVDS HSD cable 21 to the device 51.

[0005] The device 51 is connected to a ground 3 by a dedicated cable 5, the cable 5 being configured to be able to support relatively high currents, for example 25 amperes.

[0006] However, the centralized electronic management device is powered in such a way that it is likely to generate a significant current between itself and ground, for example, 25 Amperes. As disclosed by US document 5,040,168, the ground is taken from the vehicle's metal body.

[0007] Thus, if the ground connection of the centralized electronic management system fails (loss of ground connection), this current is transmitted to the high-speed transmission cables whose shielding is not suitable for these current values. The resulting cable deterioration is likely to lead to electrical contact with the vehicle body, which is used as ground, and therefore an aggravated short circuit (ACS).

[0008] For example, in [Fig.2], a loss of connection 16 occurs and disconnects the device 51 from ground 3. The current whose path is illustrated in references 55 and 56 therefore joins the other available grounds, for example the grounds 10 and 12 of components 9 and 13. In doing so, it passes through the high-speed cables 7 and 11 which are not suitable for such intensities.

[0009] There is a need to reduce the risks of aggravated short circuits due to the transmission of a large current in cables dedicated to high-speed data transmission.

[0010] It was proposed in the document with filing number FR2113034 to perform a splice to redundantly connect the centralized management device to ground. While this solution does reduce the risk of CCA, it does not completely eliminate the risk, as both connections of the device to ground may be lost.

[0011] The present invention improves the situation.

[0012] To this end, a first aspect of the invention relates to a motorized land vehicle comprising: - a centralized electronic management device of at least one first and one second electronic component, the management device comprising an electrical circuit for connection to a ground linked to the vehicle body and ensuring the connection to the ground of the management device; - the first electronic component, connected by a first cable to the management device; - the second electronic component, connected by a second cable to the management device; - the first and second cables being respectively configured for data exchange between the first component and the device and between the second component and the device, therefore, the first and the second Each cable has a specific shielding for a predetermined maximum current.

[0013] characterized in that the first and second electronic components are connected to the electrical grounding circuit to ensure the grounding of the first and second electronic components via the electrical grounding circuit.

[0014] The current recirculation problem is therefore eliminated here by connecting the components to the same ground as the centralized control unit (via the electrical circuit). Indeed, in the event of a ground loss of the control unit (for example, by breaking the connection to the chassis), the grounds of the components and the control unit will be the same (the electrical circuit) and therefore subjected to the same potential, which will not induce significant current in the cables not configured to carry such currents.

[0015] In one embodiment, the predetermined maximum current is between 2 and 3 Amperes.

[0016] In one embodiment, the predetermined maximum current is 2.5 Amperes.

[0017] In one embodiment, the electrical circuit comprises a wire comprising a shielding defined for a maximum current of 25 Amps.

[0018] In one embodiment, the electrical circuit for connecting the electronic management device to ground includes a first ground connection and a second ground connection.

[0019] In one embodiment, the first and second connections of the device to ground are obtained by splicing an initial connection of the device to ground.

[0020] In one embodiment, the splice is a Y-splice.

[0021] Other features and advantages of the invention will become apparent from an examination of the detailed description below, and the accompanying drawings in which:

[0022] [Fig.1] is a diagram illustrating an electronic system according to the prior art;

[0023] [Fig.2] is a diagram illustrating an electronic system facing a loss of connection with a mass according to the prior art;

[0024] [Fig.3] is a diagram illustrating an electronic system according to an embodiment of the invention.

[0025] The invention is described below in its non-limiting application to the case of a device relating to an infotainment system in a motor vehicle. Other applications, such as a connectivity unit mounted on the handlebars of an electric bicycle or placed on a moped headlight, are also conceivable.

[0026] Figure 3 illustrates a centralized electronic management device for a plurality of electronic components according to an embodiment of the invention.

[0027] Figure 3 incorporates the references described above in the introduction with reference to Figures 1 and 2. In particular, the motorized land vehicle comprises: - the centralized electronic management device 51 of a first electronic component 9 and a second electronic component 13. The management device comprising an electrical circuit 70 for connection to at least one ground 64, 62 linked to the vehicle body and ensuring the connection to the ground of the management device; - the first electronic component, connected by a first cable 7 to the management device; - the second electronic component, connected by a second cable 11 to the management device; - The first and second cables are configured respectively for data exchange between the first component and the device and between the second component and the device; therefore, each cable has a shield designed for a predetermined maximum current. In one embodiment, the predetermined maximum current is between 2 and 3 Amperes. In another embodiment, the predetermined maximum current is 2.5 Amperes.

[0028] The first and second electronic components are connected to the electrical grounding circuit to ensure the grounding of the first and second electronic components via the electrical grounding circuit.

[0029] In one embodiment, the electronic management device includes a first connection 62 to ground and a second connection 64 to ground.

[0030] In one embodiment, the first connection 62 and / or the second connection 64 to the ground of the device comprises a wire having a shield defined for a maximum current of 25 Amperes.

[0031] In one embodiment, the first and second connections of the device to ground are obtained by splicing 66 onto an initial connection of the device to ground. A splice here is a join between two flexible metallic assemblies (e.g., copper electrical or telecommunications wires), with a connection added by splicing onto the existing connection. The join is obtained by braiding or twisting them. In one embodiment, the splice is a Y-splice.

[0032] The present invention is not limited to the embodiments described above by way of example; it extends to other variants.

[0033] Thus, an embodiment has been described in which the invention is implemented for a device connected to a device related to an infotainment system of a motor vehicle. The invention can, however, be implemented for any type of electronic device linked to other electronic components connected to said device by high-speed data transmission cables not suitable for high currents.

Claims

Demands

1. Motor vehicle comprising: - an infotainment system (51) allowing centralized electronic management of at least a first and a second electronic component, the infotainment system comprising an electrical circuit for connection to a ground linked to the body of the vehicle and ensuring the connection to the ground of the management device; - the first (9) electronic component, connected by a first cable (7) to the infotainment system; - the second (13) electronic component, connected by a second cable (11) to the infotainment system;- the first and second cables being respectively configured for data exchange between the first component and the infotainment system and between the second component and the infotainment system, therefore, the first and second cables each have a shield defined for a predetermined maximum current, characterized in that the first and second electronic components are connected to the electrical grounding circuit to ensure the grounding of the first and second electronic components via the electrical grounding circuit.;

2. Vehicle according to claim 1, in which the predetermined maximum current is between 2 and 3 Amperes.

3. Vehicle according to claim 2, wherein the predetermined maximum current is 2.5 Amperes.

4. Vehicle according to any one of the preceding claims, wherein the electrical circuit comprises a wire having a shield defined for a maximum current of 25 Amperes.

5. Vehicle according to any one of the preceding claims, wherein the electrical grounding circuit of the infotainment system comprises a first ground connection and a second ground connection.

6. Vehicle according to claim 5, wherein the first and second connections of the infotainment system to ground are obtained by splicing (66) an initial connection of the device to ground.