BIPOLAR ELECTRICAL CIRCUIT

Abstract

A bipolar electrical circuit comprising: - a first terminal (B1, B3) and a second terminal (B2, B4) for electrical connection, designed to receive a potential difference according to a predefined polarity (V) for supplying current to the bipolar electrical circuit, - an electrical warning device (1), coupled to the first (B1, B3) and second (B2, B4) terminals, and configured to operate under a reversed polarity (Vinv) with respect to the predefined polarity (V) when it is supplied with current, the electrical circuit comprising a one-way current switch (3) interposed between one of the terminals and the electrical warning device (1), this switch (3) being oriented in the forward direction of current only for the reversed polarity (Vinv). Figure 1.

Description

Title of the invention: BIPOLAR ELECTRICAL CIRCUIT

[0001] In the field of motor vehicles, and more generally in the electrical field, bipolar electrical circuits are well known and designed to operate according to a predefined polarity. By convention, and throughout this document, these polarities will be denoted + and -, the negative polarity generally being the reference potential known as "ground" because it is often coupled to the body and / or metal chassis of vehicles, but this is not mandatory.

[0002] The loads or components included in this bipolar circuit are, for the most part, intended to be supplied according to this predefined polarity and if by chance this polarity is reversed, following an assembly error or a risky maintenance intervention, these loads or components may be damaged or even short-circuited.

[0003] For example, the on-board electrical system of a vehicle, generally powered by a DC battery with a voltage between 11 and 30V, or other voltage ranges, includes control units and other components such as a horn, a windshield wiper motor, the instrument panel, relays controlling other actuators, an alternator, and a starter motor, this list being by no means exhaustive. The control units are particularly sensitive to polarity.

[0004] This risky maintenance procedure is, for example, attempting to start a vehicle with a discharged auxiliary battery using a portable charger with a powerful energy storage unit, often known as a "booster." It is also, for example, jump-starting a vehicle using jumper cables to connect the two batteries in parallel, or simply changing the battery. Despite the pictograms clearly indicating the correct polarity for connecting the auxiliary battery terminals (positive to positive, negative to negative), which may become less visible over time, this polarity can sometimes be reversed, and the vehicle's electrical system can be seriously damaged because it is not always possible to protect all the control units and other components of the electrical system against this polarity reversal.

[0005] The object of the invention is to remedy this problem. To this end, the invention relates to a bipolar electrical circuit comprising: - a first terminal and a second electrical connection terminal designed to receive a potential difference according to a predefined polarity, - an electrical warning device, coupled to the first and second terminals, and configured to operate under a reverse polarity relative to the predefined polarity when supplied with current, this electrical circuit comprising a one-way current switch interposed between one of the terminals and the electrical warning device, this switch being oriented in the current-passing direction only for the reverse polarity.

[0006] The term "predefined polarity" refers to a single polarity direction for which loads or actuators, for example, in a vehicle's onboard network, are designed to operate using this polarity. This is the normal polarity direction. Examples of such loads include computers, a windshield wiper motor, the instrument panel, control relays for other actuators, an alternator, and a starter motor. Conversely, reversed polarity corresponds to an abnormal or malfunctioning polarity, for example, resulting from improper maintenance.

[0007] Thus, this circuit is simple, the electrical warning device being directly connected to the terminals via only the switch: there is no control management, no voltage measurement, no calculation, and the electrical warning device is activated as soon as the polarity is reversed, for example, as soon as the booster or emergency battery is incorrectly connected to the terminals. The operator is thus immediately warned, pleasantly surprised, and will instinctively disconnect the booster from one of the terminals. By disconnecting it quickly, the risk of damage is limited, and the power-up of the loads or actuators to be controlled will not be under the wrong polarity.

[0008] According to one embodiment of the invention, this electrical circuit comprises an electrical switch having a current-cut-off position and a closing position, coupled in parallel to the one-way current switch, and suitable for supplying the warning electrical device only if the electrical switch is in the closing position, the warning electrical device being configured to operate regardless of the direction of polarity.

[0009] Thus, the invention can use a pre-existing electrical warning device, the normal actuation of which is controlled by the electrical switch. The invention then merely adds this switch in parallel with the electrical switch.

[0010] Thus, this bipolar electrical circuit includes, for example: - the first and second electrical connection terminals designed to receive the potential difference according to the predefined polarity, - the electrical warning device, coupled to the first and second terminals, and configured to operate regardless of polarity if it is powered, - the electrical switch having the current cut-off position and the closing position, coupled to one of the terminals on one side, and to the electrical warning device on the other side, and suitable for supplying the electrical warning device only if the electrical switch is in the closing position, this electrical circuit comprising the one-way current switch coupled in parallel with the electrical switch, this switch being oriented in the current-passing direction only for the reverse polarity with respect to the predefined polarity.

[0011] According to one embodiment of the invention, the electrical warning device is a horn. For example, this horn emits a sound greater than 80 decibels. For example, this horn emits a sound between 80 and 130 decibels, sometimes up to 300 decibels for ships or, in a regulated manner for automobiles in certain countries, between 95 and 110 decibels.

[0012] Thus, the operator's element of surprise is guaranteed. The operator's reflex will be to jump, thereby disconnecting the "booster" from one of the terminals by its backward movement.

[0013] According to one embodiment of the invention, the one-way current switch is a diode.

[0014] According to one embodiment of the invention, this electrical circuit includes an electromagnetic relay comprising the electrical switch.

[0015] According to one embodiment of the invention, this electrical circuit includes a transistor comprising the electrical switch.

[0016] The invention further relates to a motor vehicle comprising a bipolar electrical circuit as previously described.

[0017] According to one embodiment of the invention, this vehicle includes an on-board network comprising the bipolar electrical circuit.

[0018] According to one embodiment of the invention, this vehicle includes a service battery coupled to the two electrical connection terminals.

[0019] According to one embodiment of the invention, this auxiliary battery provides a voltage between 11 and 30 V.

[0020] Other features and advantages will become apparent from the following description of a particular, non-limiting embodiment of the invention, made with reference to the single [Fig. 1] in which:

[0021] [Fig.l]: represents an embodiment of the electrical circuit according to the invention.

[0022] Figure 1 discloses a bipolar electrical circuit according to the invention, comprising: - a first terminal Bl, B3 and a second terminal B2, B4 for electrical connection, designed to receive a potential difference according to a predefined polarity V for supplying current to the bipolar electrical circuit, - an electrical warning device 1, coupled to the first Bl, B3 and second B2, B4 terminal, and configured to operate under a reversed polarity Vinv relative to the predefined polarity V when it is energized with current, the electrical circuit comprising a one-way current switch 3 interposed between one of the terminals and the electrical warning device 1, this switch 3 being oriented in the current-passing direction only for the reversed polarity Vinv.

[0023] This electrical circuit includes, for example, an electrical switch 2 having a current-cutting position and a closing position, coupled in parallel to the one-way current switch 3, and suitable for supplying the warning electrical device 1 only if the electrical switch 2 is in the closing position, the warning electrical device 1 being configured to operate regardless of the direction of the polarity V, Vinv.

[0024] Thus, this bipolar electrical circuit includes, for example: - the first terminal Bl, B3 and the second terminal B2, B4 for electrical connection, designed to receive the potential difference according to the predefined polarity V, - the electrical warning device 1, coupled to the first Bl, B3 and second B2, B4 terminal, and configured to operate regardless of the polarity direction V, Vinv if it is powered, - the electrical switch 2 having the current cut-off position and the closing position, coupled to one of the terminals Bl, B3, B2, B4 on the one hand, and to the electrical warning device 1 on the other hand, and suitable for supplying the electrical warning device 1 only if the electrical switch 2 is in the closing position, this electrical circuit comprising the one-way current switch 3 coupled in parallel with the electrical switch 2, this switch 3 being oriented in the current-passing direction only for the reversed polarity Vinv with respect to the predefined polarity V.

[0025] Advantageously, the electrical warning device 1 is a horn, in particular an automotive-type horn located in the same compartment or near terminals B1, B2, B3, B4.

[0026] For example, the current one-way switch 3 is a diode, in particular a switching diode, widely known to man in the art.

[0027] For example, this electrical circuit includes an electromagnetic relay 4 comprising the electrical switch 2. Thus, the electrical switch is controlled by a coil generating a magnetic flux in one or two directions, depending on whether the switch is monostable or bistable. Note that it is advantageous for the electrical switch 2 to be normally open, so that the coil does not consume any current as long as the electrical warning device 1 does not need to be activated.

[0028] In an alternative, not shown, this electrical circuit includes a transistor comprising the electrical switch 2. The principle is identical to the relay, but more miniaturized.

[0029] This invention applies in particular to a motor vehicle comprising this bipolar electrical circuit.

[0030] For example, this vehicle includes an on-board network L1+, L1-, L2+, L2- comprising the bipolar electrical circuit.

[0031] For example, in [Fig. 1], a first power supply line L1- for the on-board network is shown, connected to the first terminal B1, and a second power supply line L1+ for the on-board network is connected to the second terminal B2. The predefined polarity V is represented by the potential difference between the first line L1- and the second line L1+, and the reversed polarity Vinv is represented by the potential difference between the second line L1+ and the first line L1-. The loads or actuators listed previously, which comprise the on-board network, are, for example, powered by the lines L1+ and L1- and are not shown in [Fig. 1]. Or more precisely, they are symbolized by the dashed lines extending from the lines L1+ and L1-.

[0032] The electrical circuit is part of the on-board network and is connected to the same potential as lines L1+ and L1-, respectively via lines L2+ and L2- at terminals B1 and B2. However, this electrical circuit can be connected to other terminals, for example, terminals B3 and B4, which are the terminals of a service battery 5, unlike terminals B1 and B2, which correspond to nodes further from battery 5. It is clear that this electrical circuit, regardless of the positions of terminals B1, B2, B3, and B4, is connected to the same potential as lines L1+ and L1-; in other words, line L1+ is at the same potential as line L2+, and line L1- is at the same potential as line L2-, for example, the reference potential, also known as ground potential. The entire on-board network is at the same potential, V, during normal operation.

[0033] For example, this vehicle includes the auxiliary battery 5 connected to the two electrical connection terminals B1, B2, B3, B4. This auxiliary battery 5 provides a voltage between 11 and 30 V, and more generally between 11 and 15 V. This battery may be of so-called lead-acid technology, but is increasingly being replaced by so-called lithium-ion batteries, all of which are well known to those skilled in the art. This auxiliary battery has, for example, a capacity between 50 and 400 Ah or even more, more generally between 80 and 200 Ah.

[0034] It should be noted that [Fig. 1] also shows a fuse 6 for protecting the electrical warning device 1. This fuse 6 is, for example, connected in series between switch 3 and / or switch 2 and the electrical warning device 1. Thus This 6A fuse interrupts the L2+ line in case of overcurrent, but could be positioned anywhere else on the L2+ or L2- line. As a rough guide, a 60W horn at 12V will draw a nominal amperage of 5A, so an 8A fuse would be suitable. Of course, there are horns with higher power ratings, up to 200W or even more.

[0035] For example, this horn emits a sound greater than 80 decibels. For example, this horn emits a sound between 80 and 120 decibels, sometimes up to 300 decibels for ships or, in a regulated manner for automobiles in some countries, between 95 and 110 decibels.

Claims

Demands

1. Bipolar electrical circuit comprising: - a first terminal (B1, B3) and a second terminal (B2, B4) for electrical connection suitable for receiving a potential difference according to a predefined polarity (V) for supplying current to the bipolar electrical circuit, - an electrical warning device (1), coupled to the first (B1, B3) and second (B2, B4) terminal, and configured to operate under a reversed polarity (Vinv) with respect to the predefined polarity (V) when it is supplied with current, characterized in that the electrical circuit comprises a one-way current switch (3) interposed between one of the terminals and the electrical warning device (1), this switch (3) being oriented in the forward direction of the current only for the reversed polarity (Vinv).

2. Electrical circuit according to claim 1, comprising an electrical switch (2) having a current-cut-off position and a closing position, coupled in parallel to the one-way current switch (3), and suitable for supplying the electrical warning device (1) only if the electrical switch (2) is in the closing position, the electrical warning device (1) being configured to operate regardless of the direction of polarity (V, Vinv).

3. Electrical circuit according to claim 2 comprising an electromagnetic relay (4) comprising the electrical switch (2).

4. Electrical circuit claim 2 comprising a transistor comprising the electrical switch (2).

5. Electrical circuit according to any one of the preceding claims, the warning electrical device (1) being a horn.

6. Electrical circuit according to any one of the preceding claims, the current one-way switch (3) being a diode.

7. Motor vehicle comprising a bipolar electrical circuit according to any one of the preceding claims.

8. Vehicle according to claim 7, this vehicle comprising an on-board network comprising the bipolar electrical circuit.

9. Vehicle according to claim 8, comprising a service battery (5) coupled to the two electrical connection terminals (B1,B2, B3, B4).

10. Vehicle according to claim 9, this auxiliary battery (5) providing a voltage between 11 and 30 V.

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