Patent Description:
ADR regulations concerns the road transportation of hazardous goods. ADR is an acronym for the expression - originally in French - "Agreement concerning the International Carriage of Dangerous Goods by Road". The aim of ADR regulations is to ensure the safety of the driver and operators when the hazardous material are being loaded or unloaded or hazardous operation are done near the truck.

Under ADR regulations, a vehicle - usually a truck - carrying hazardous materials must be equipped with a safety switch, which must be triggered by the driver or by an operator around the vehicle, for any activity involving hazardous materials, such as loading/unloading of hazardous material, presence of explosives materials, etc. ADR regulations states that as soon as the safety switch is triggered, any electric equipment or accessory of the vehicle, more generally any electric load of the vehicle, shall be cut off from its electric power supply within <NUM> milliseconds. Document <CIT> describes, for example, a battery isolating device that comprises two electronically operated switches, each arranged on a supply line connected to a respective pole, plus or minus, of the battery, in order to reduce discharge of the battery when the vehicle is parked for a long period of time. However, when a truck comprises additional power sources such as, for example, a solar panel, an additional battery or a capacitor, such additional power source might continue to provide electric power to an accessory, for example in case of defect or wrong usage, which could lead to dangerous, potentially life threatening, situations. To this end, the invention aims at providing a security system circuit for a vehicle, which provides improved safety.

According to a first aspect of the invention, the invention relates to a security system circuit for a vehicle, the security system comprising an electronic main control unit, and at least one electronically operated switch, which is arranged on an input line of an electric load of the vehicle, each electronically operated switch being controlled by the main control unit and being is configured to switch between a connected configuration, where said electronically operated switch allows electricity to flow through the input line between a main electric power source of the vehicle and the electric load, and a cutoff configuration, where said electronically operated switch prevents electricity from circulating through the input line between the main power source and said electric load. The security system also comprises a safety switch, configured to be activated by a user of the vehicle, the safety switch being configured to control the main control unit, so that each electronically operated switch switches to its cutoff configuration when the safety switch is activated. The security system further comprises an electronic safety control unit, which is different from the main control unit, the safety control unit being powered by the main power source, at least one current sensor, each current sensor being is configured to detect electric current flowing through a respective input line of said electric load, and alarm means, configured to alert a user of the vehicle. The safety control unit is configured to change from a waiting mode to an active mode under the control of the main control unit, the safety control unit changing to the active mode when the safety switch is activated, and to activate the alarm means when the safety control unit is in the active mode, and after a predetermined first time interval from the moment the safety switch is activated, at least one current sensor detects electric current flowing through the corresponding input line.

A technical benefit may include alerting the user(s) in and/or around the vehicle in case of the electric load still uses electric power despite the safety switch being triggered. The safety of the truck is therefore improved.

In some examples, after the safety control unit activates the alarm means, the safety control unit turns off the alarm means after a predetermined second time interval. A technical benefit may include alerting the user of a potential malfunction of the main control unit without startling the user.

In some examples, the second time interval ends <NUM> after the safety switch is activated. A technical benefit may include fulfilling ADR regulation for the safety system itself.

In some examples, first time interval is equal to <NUM> after the safety switch is activated. A technical benefit may include allowing the transient electrical phenomenon occurring after the opening of each electronically operated switch, to end, in order to avoid false alarms.

In some examples, the at least one electronically operated switch includes an additional electronically operated switch, whereas the power supply of the safety control unit is controlled by the main control unit through the additional electronically operated switch, and whereas the main control unit is configured to switch said additional electronically operated switch in its cutoff configuration after a predetermined time interval after the safety switch is activated. A technical benefit may include improving the overall safety by including the safety control unit in its own supervision.

A second aspect of the invention concerns a road vehicle, in particular a truck, comprising the security system as previously described, a main power source, for example a battery, and one electric load with at a first input line, which is connected to the main power source, whereas the at least one current sensor include a first sensor, which is arranged on the first input line.

A technical benefit may include having a vehicle with improved safety when handling dangerous goods.

In some examples, the road vehicle comprises an additional power source, for example a capacitor or a solar panel, the additional power source being different from the main power source, the electric load comprises a second input line, which is different from the first input line and which is connected to the additional power source, whereas the at least one current sensor include a second sensor, which is arranged on the second input line. A technical benefit may include improving the safety of road vehicles comprising additional power sources.

A third aspect of the invention concerns a supervision method to supervise electric accessories of a vehicle comprising the security system previously described, the supervision method comprising the following steps:.

A technical benefit may include the same advantages as those mentioned above for the security system of the invention.

In some examples, the supervision method comprises the following additional steps: after activating the alarm means, turning off alarm the means after a predetermined second time interval.

A technical benefit may include alerting the user of a potential malfunction of the main control unit without startling the user.

In some examples, the second time interval ends <NUM> after the safety switch is activated. A technical benefit may include ensuring that the alarm means themselves fulfill ADR regulations.

In some examples, the first time interval is equal to <NUM>. A technical benefit may include allowing the transient electrical phenomenon occurring after the opening of each electronically operated switch, to end, in order to avoid false alarms.

Additional features and advantages are disclosed in the following description, claims, and drawings, and in part will be readily apparent therefrom to those skilled in the art or recognized by practicing the invention as described herein.

With reference to the appended drawings, below follows a more detailed description of aspects of the invention cited as examples.

Aspects set forth below represent the necessary information to enable those skilled in the art to practice the invention.

<FIG> is an exemplary vehicle <NUM> according to an embodiment of the invention. The vehicle <NUM> is a road vehicle and is configured to carry goods that fall under the ADR definition, in other words dangerous goods. In the illustrated example, the vehicle <NUM> is represented by a cistern truck and comprises a cistern <NUM>, which is arranged on top of a chassis <NUM>. Of course, the type of vehicle <NUM> may vary, depending on the type of dangerous goods to be transported. The vehicle <NUM> also comprises a cabin <NUM> for a driver of the vehicle <NUM>.

The vehicle <NUM> comprises a security system <NUM>, which is represented schematically on <FIG>. The security system <NUM> comprises at least one safety switch <NUM>. Each safety switch <NUM> is configured to be activated by a user of the vehicle <NUM> when needed. In the illustrated example, the vehicle <NUM> comprises two safety switches <NUM>, with a first safety switch <NUM> arranged inside the cabin <NUM>, here on a dashboard <NUM>, and a second safety switch <NUM> arranged outside the cabin <NUM>. In the illustrated example, the second safety switch <NUM> is arranged on the chassis <NUM> at a rear end of the vehicle <NUM>. In the illustrated example, the safety switches <NUM> are represented by pushbuttons. The number, location and shape of the safety switches <NUM> are not limitative.

The vehicle <NUM> comprises a main power source <NUM>, for example a battery such as an acid-lead battery. The main power source <NUM> is configured to store electric power, and to release, when needed, electric power. The vehicle <NUM> also comprises a secondary power source <NUM>, which is different from the main power source <NUM>. For example, the secondary power source <NUM> is a lithium-ion battery, which is configured to harvest electric energy generated while braking, or a solar panel, etc..

The vehicle <NUM> also comprises an electric load <NUM>. According to non-limiting examples, the electric load <NUM> is a pump, a compressor, a cooling system, etc. More generally, the electric load <NUM> is a piece of equipment that is powered by electricity. The electric load <NUM> comprises a first input line <NUM>, which is connected to the main power source <NUM>. The first input line <NUM> is represented by a line on <FIG>, with an arrow illustrating the flow of electric power, from the main power source <NUM> to the electric load <NUM>. The electric load <NUM> also comprises a second input line <NUM>, which is different from the first input line <NUM> and which is connected to the secondary power source <NUM>.

The security system <NUM> also comprises an electronic main control unit <NUM> and a first electronically operated switch <NUM>. The first electronically operated switch <NUM> is arranged on the first input line <NUM>, that is to say between the main power source <NUM> and the electric load <NUM>. The electronically operated switch124 is controlled by the main control unit <NUM> and is configured to switch between a connected configuration, where said electronically operated switch <NUM> allows electric current to flow between the main power source <NUM> and the electric load <NUM>, and a cutoff configuration, where the electronically operated switch <NUM> prevents electric current from circulating between the main power source <NUM> and the electric load <NUM>. The electronically operated switch <NUM> is schematically represented on <FIG>. Preferably, the electronically operated switch <NUM> is a solid-state relay, for example a thyristor, which is controlled by the main control unit <NUM>.

The main control unit <NUM> is controlled by the safety switch <NUM>, so that the electronically operated switch <NUM> switches to its cutoff configuration when the safety switch <NUM> is activated. According to some examples, each safety switch <NUM> is connected to the main control unit <NUM> through a data bus of the vehicle <NUM>, such as a CAN bus. The data bus is not represented. More generally, any connection for data transmission may be done through a data bus of the vehicle, such as a CAN bus, while connection for electric power transmission are preferably done through dedicated electric wires.

The security system <NUM> also comprises an electronic safety control unit <NUM>. The safety control unit <NUM> is different from the main control unit <NUM>. The safety control unit <NUM> is powered by the main power source <NUM> through a supply line <NUM>.

Preferably, the supply line <NUM> of the safety control unit <NUM> is controlled by the main control unit <NUM> through an additional electronically operated switch <NUM>. The additional electronically operated switch is similar, preferably identical, to the other electronically operated switch(s) <NUM> associated to the electric load(s) <NUM>. The additional electronically operated switch <NUM> is controlled by the main control unit <NUM>, more precisely the main control unit <NUM> is configured to switch said additional electronically operated switch125 in its cutoff configuration after a predetermined time interval after the safety switch is activated.

The security system <NUM> also comprises at least one current sensor <NUM>, including a first sensor 134A. In the illustrated example, the first sensor 134A is arranged on the first input and is schematically represented by a loop around the first input line <NUM>. The safety control unit <NUM> is configured to receive data from each current sensor <NUM>, for example data representing the intensity of an electric current measured by the sensor <NUM>, or data representing whether an electric current is actually circulating or not. In a not shown alternative, the current sensor 134A is integrated with the electronically operated switch <NUM> associated with the first input line <NUM>. In another, not shown, alternative, the additional electronically operated switch <NUM> also integrates an additional current sensor.

The at least one current sensor <NUM> advantageously includes a second sensor 134B, which is different from the first sensor 134A and which is arranged on the second input line <NUM>. The second sensor 134B is configured to detect electric current circulating through the second input line <NUM>. More generally, each current sensor <NUM> is arranged on a respective input line or supply line, each current sensor <NUM> being configured to detect electric current circulating through the corresponding line.

The security system <NUM> also comprises alarm means <NUM>. The alarm means <NUM> are configured to alert a user of the vehicle <NUM>, in particular when said user presses one of the safety switches <NUM>. In the illustrated example, the alarm means <NUM> include a horn <NUM>, arranged on the top of the cabin <NUM>, a buzzer <NUM> arranged inside the cabin, and lights <NUM> arranged on the chassis <NUM>. The number, location and types of alarm means <NUM> is not limitative.

Working principles of the security system <NUM> are detailed hereinafter.

During normal operations of the vehicle <NUM>, the safety switches <NUM> are in a deactivated configuration, while the safety control unit <NUM> is in a first mode, for example a waiting mode. The alarm means <NUM> are not activated, and the electronically operated switches <NUM> and <NUM> are in their connected configuration.

Advantageously, when the safety control unit <NUM> is in the waiting mode, the safety control unit <NUM> monitors the data received from each current sensors <NUM>. In case of an abnormal situation, for example if the current value measured by any one of the current sensors <NUM> rises above a predetermined threshold, then the safety control unit <NUM> alerts a user of the vehicle <NUM>. For example, the safety control unit <NUM> activates the alarm means <NUM> in a specific way to alert the user without startling the user - especially if the user is driving.

When needed, for example when loading the vehicle <NUM> with dangerous goods, or in case of an abnormal situation, a user triggers one of the safety switches <NUM>. As one of the safety switches <NUM> is triggered, the main control unit <NUM> switches the electronically operated switch <NUM> to its cutoff configuration, in order to disconnect the electric load <NUM> from the main power source <NUM>. When the vehicle <NUM> comprises several electric loads <NUM>, each associated with a respective electronically operated switch <NUM>, then the main control unit <NUM> switches each electronically operated switch <NUM> to its cutoff configuration.

Also, when one of the safety switches <NUM> is activated, the main control unit <NUM> activates the safety control unit <NUM> to an active mode. When in the active mode, the safety control unit <NUM> receives data from each current sensor <NUM>.

If, after a predetermined first time interval from the moment the safety switch <NUM> is activated, any one of the current sensors <NUM> detects an electric current flowing through the input line <NUM>, then the safety control unit <NUM> activates the alarm means <NUM>, in order to alert the user that the electric load <NUM> is not properly deactivated. An electric current flowing through the input line <NUM> means that a current above a predetermined current threshold is circulating in said input line. For example, the predetermined current threshold is proportional to a sensitivity threshold of the current sensor <NUM>.

When the security system <NUM> works properly, the first time interval is set to allow transient electrical phenomenon to disappear after each electronically operated switch <NUM> is switched to its cutoff configuration, in order to avoid false alarms. For example, the first time interval is equal to <NUM> - milliseconds - after the safety switch <NUM> is activated.

Advantageously, after the safety control unit <NUM> activates the alarm means <NUM>, the safety control unit <NUM> turns off the alarm means <NUM> after a predetermined second time interval. Preferably, the second time interval ends <NUM> - milliseconds - after the safety switch <NUM> is activated, in order to fulfill ADR regulations.

Similarly, the safety control unit <NUM> itself is also an electric equipment of the vehicle <NUM>, and as such the safety control unit <NUM> itself should fulfill ADR regulations. Preferably, when the safety switch <NUM> is activated, the main control unit <NUM> is configured to switch the additional electronically operated switch <NUM> in its cutoff configuration after a predetermined third time interval after the safety switch <NUM> is activated, so that the safety control unit <NUM> itself is turned-off. Preferably, the third time interval is shorter than <NUM>, for example equal to <NUM>.

Advantageously, the safety control unit <NUM> comprises a timer, configured to count the elapsed time after the safety control unit <NUM> is switched to its active configuration until the safety control unit <NUM> itself is turned off. If the elapsed time exceeds the third time interval, meaning that the main control unit <NUM> did not properly switch the additional electronically operated switch <NUM> to its cutoff configuration, then the safety control unit <NUM> activates the alarm means <NUM>.

Based on the example of the security system <NUM> described above, the invention also concerns a supervision method to supervise the electric loads of the vehicle <NUM>. This supervision method is preferably implemented using the safety control unit <NUM> previously described.

With reference to <FIG>, the safety control unit <NUM> is initially in the waiting mode. Waiting mode is represented by a box <NUM>. If the safety switch <NUM> is activated, then the safety control unit <NUM> switches to the activated mode. Activated mode is represented by a box <NUM>. While in the activated mode <NUM>, the safety control unit <NUM> receives data from the current sensors <NUM>. Reception of data is represented by a box <NUM>.

If, after the predetermined first time interval from the moment the safety switch <NUM> is activated, data received from the current sensors <NUM> show that at least one current sensor <NUM> detects electric current flowing through the corresponding input line, then the safety control unit <NUM> activates the alarm means <NUM>. Activation of the alarm means <NUM> is represented by a box <NUM>.

The first time interval is longer that <NUM>, preferably longer that <NUM>, even more preferably longer than <NUM>. For example, the first time interval is equal to <NUM>.

Advantageously, after the safety control unit <NUM> activates the alarm means <NUM>, the safety control unit <NUM> turns off the alarm means <NUM> after a predetermined second time interval. The second time interval ends preferably <NUM> after the safety switch is activated.

Advantageously, when the safety control unit <NUM> is in the active configuration, the safety control unit <NUM> starts a timer, to count time elapsed since the safety control unit <NUM> is switched to its active mode, until the power supply of the safety control unit <NUM> is cut-off by the additional electronically operated switch <NUM>, in other words until the safety control unit <NUM> is turned off. If the elapsed time reaches the predetermined third time interval, then the safety control unit <NUM> activates the alarm means <NUM>. Preferably, the third time interval is shorter than <NUM>.

The terminology used herein is for the purpose of describing particular aspects only and is not intended to be limiting of the invention.

For example, a first element could be termed a second element, and, similarly, a second element could be termed a first element without departing from the scope of the present invention.

Claim 1:
A security system (<NUM>) circuit for a vehicle (<NUM>), the security system comprising:
- an electronic main control unit (<NUM>),
- at least one electronically operated switch (<NUM>), which is arranged on an input line (<NUM>) of an electric load (<NUM>) of the vehicle, each electronically operated switch (<NUM>) being controlled by the main control unit (<NUM>) and being is configured to switch between:
• a connected configuration, where said electronically operated switch (<NUM>) allows electricity to flow through the input line (<NUM>) between a main electric power source (<NUM>) of the vehicle and the electric load (<NUM>), and
• a cutoff configuration, where said electronically operated switch (<NUM>) prevents electricity from circulating through the input line (<NUM>) between the main power source (<NUM>) and said electric load (<NUM>),
- a safety switch (<NUM>), configured to be activated by a user of the vehicle, the safety switch (<NUM>) being configured to control the main control unit (<NUM>), so that each electronically operated switch (<NUM>) switches to its cutoff configuration when the safety switch (<NUM>) is activated,
characterized in that the security system (<NUM>) further comprises:
- an electronic safety control unit (<NUM>), which is different from the main control unit (<NUM>), the safety control unit being powered by the main power source (<NUM>),
- at least one current sensor (<NUM>), each current sensor being is configured to detect electric current flowing through a respective input line (<NUM>) of said electric load (<NUM>), and
- alarm means (<NUM>), configured to alert a user of the vehicle,
wherein the safety control unit (<NUM>) is configured:
- to change from a waiting mode to an active mode under the control of the main control unit (<NUM>) , the safety control unit (<NUM>) changing to the active mode when the safety switch (<NUM>) is activated, and
- to activate the alarm means (<NUM>) when:
• the safety control unit (<NUM>) is in the active mode, and
• after a predetermined first time interval from the moment the safety switch (<NUM>) is activated, at least one current sensor (<NUM>) detects electric current flowing through the corresponding input line (<NUM>).