Fuel supply system for a motor vehicle with an activatable refueling lock and method for activating the refueling lock

Abstract

Fuel supply system (100) for a motor vehicle with an internal combustion engine, comprising: - a fuel tank (110); - a filling pipe (140) leading into the fuel tank (110), through which fuel (K) flows into the fuel tank (110) during refueling; - a venting device (150) through which air (L) can escape from the fuel tank (110) via a venting path (151) during refueling, wherein at least one electrically switchable valve (152) is arranged in the venting path (151) with which the venting path (151) can be opened and closed; - a control unit (160) which, in the event of unauthorized operation of the motor vehicle, closes the electrically switchable valve (152), making refueling via the filler pipe (140) impossible.

Description

[0001] The invention relates to a fuel supply system for a motor vehicle with an internal combustion engine, comprising a fuel tank and a venting device for this fuel tank.

[0002] The invention further relates to a method for activating a refueling lock in such a fuel supply system, as well as to a motor vehicle with such a fuel supply system.

[0003] Currently manufactured motor vehicles (such as passenger cars, buses, trucks, and construction machinery) are mostly equipped with systems to secure the vehicle against unauthorized use. A common system for vehicles with internal combustion engines is the electronic immobilizer, which is also legally required in some countries. For example, German patent DE 10 2004 057 744 A1 describes a method by which an engine control unit and a fuel supply control unit interact to prevent theft of the vehicle.

[0004] The invention is intended to improve protection against unauthorized use of a motor vehicle with an internal combustion engine.

[0005] This is achieved with the fuel supply system according to the invention, comprising the features of claim 1. By a first dependent claim, the invention also extends to a method for activating the refueling lock in a fuel supply system according to the invention. By a second dependent claim, the invention further extends to a motor vehicle with a fuel supply system according to the invention. Preferred embodiments and configurations of the invention are described analogously for all subject matter of the invention in the dependent claims, the following description of the invention, and also in the drawings.

[0006] The fuel supply system according to the invention comprises at least the following components: - a fuel tank or reservoir, which is typically connected to the internal combustion engine via a supply line; - a filler pipe or similar opening into the fuel tank, through which fuel flows into the fuel tank during refueling; - a venting device or venting system through which air can escape from the fuel tank via a venting path during refueling, wherein at least one electrically switchable valve is arranged in the venting path with which the venting path can be opened and closed or selectively opened or closed; and - a control unit or control device which, in the event of unauthorized operation of the motor vehicle, closes the electrically switchable valve of the venting device, making refueling via the filler pipe impossible.

[0007] The venting path is typically closed by a valve at the end of the refueling process (thus ending the refueling process) once a defined fill level (level) in the fuel tank is reached. As soon as the fill level drops during vehicle operation, the valve opens again, or can be opened manually, allowing refueling to resume. This opening and closing can occur automatically, for example, if the valve is designed as a float valve. Alternatively, this opening and closing can be controlled by the engine control unit (ECU), provided the valve is capable of being controlled accordingly (for example, if it is electronically controlled). The valve can then be opened during the refueling process (e.g., via a pressure-holding function) and then closed again at the end of the process.The invention provides that this valve, or another valve arranged in the venting path, is electrically switchable (this is also possible with a float valve), in particular by having or being connected to an electrical actuator, and that in the event of unauthorized operation of the motor vehicle, especially after the theft of the motor vehicle, the control unit switches it permanently, or at least during the intended refueling process, to a closed state, thereby also closing the venting path. During an intended refueling process, little or no fuel can flow into the fuel tank via the filler neck, since the air (or a fuel vapor-air mixture) trapped in the fuel tank cannot escape. The fuel supply system according to the invention thus has an activatable refueling lock that prevents refueling.

[0008] The control unit is therefore designed to close at least one electrically switchable valve of the ventilation system in the event of unauthorized operation of the vehicle. This can be achieved, in particular, by means of suitable software running on the control unit. The switching can be initiated by the control unit communicating directly with the electrically switchable valve, for example, via a vehicle bus system, or indirectly, for example, via a relay. The control unit can be a standalone unit. It can also be integrated into another control unit, such as a fuel supply control unit or an engine control unit.

[0009] The fuel supply system according to the invention thus features an activatable refueling lock that is easy to implement yet highly effective. While this refueling lock cannot directly prevent unauthorized use, particularly theft, of the vehicle, it does prevent the vehicle from being refueled and driven, rendering it virtually worthless, especially if unlocking the lock requires, for example, only the manufacturer or major modifications to the vehicle. It is therefore essentially an indirect anti-theft system, which can be used to equip a vehicle, particularly as a supplement to direct anti-theft systems such as the aforementioned immobilizer.

[0010] Preferably, the electrically switchable valve has a home position in which it is closed. The electrically switchable valve can thus be closed to its home position by resetting, in particular by automatic resetting. The fuel supply system according to the invention can also include a relay controlled or controllable by the control unit, which interrupts the power supply to the electrically switchable valve in the event of unauthorized operation of the motor vehicle, so that the electrically switchable valve switches to its closed home position. The relay can be equipped with a reset lock, so that resetting or restoring the power supply is not possible or only possible with difficulty.

[0011] The fuel supply system according to the invention can further comprise a theft detection device configured to detect theft of the motor vehicle and to notify the control unit of the unauthorized operation of the motor vehicle. A theft detection device is already known from the previously cited DE 10 2004 057 744 A1. In this case, theft detection takes place within the vehicle, e.g., via specific routines, such as querying an ignition key identification number signal. The theft detection device can be a separate device or integrated into the control unit.

[0012] The fuel supply system according to the invention can further comprise a radio receiver configured to receive an externally transmitted theft detection signal (e.g., via WLAN, Bluetooth, mobile networks, or the like) and to notify the control unit of the unauthorized operation of the motor vehicle. In this case, theft detection is carried out externally, e.g., by the owner (who can, for example, communicate with the radio receiver using a mobile app), the manufacturer, or an authority. The radio receiver can be a separate device or integrated into the control unit.

[0013] The inventive method for activating the refueling lock comprises at least the following steps: - Detection of unauthorized operation of the motor vehicle, e.g. by theft of the motor vehicle, in particular by a theft detection signal received by the radio receiver (so); - Automatic closing of the electrically switchable valve (the venting device) initiated by the control unit, making it impossible to refuel the fuel tank (via the filler pipe).

[0014] The preceding explanations refer to a refueling venting system that is effective during the refueling process and is accessed via a refueling venting path with at least one refueling venting valve. The venting device of the fuel supply system according to the invention can also include an operational vent for the fuel vapor generated in the fuel tank. This operational vent can be combined with or connected to the refueling venting system, or it can have a separate operational venting path, so that operational and refueling venting are separate. If the venting device optionally has several venting paths (e.g., at least one refueling venting path and at least one operational venting path), it is preferably provided that at least one electrically switchable valve (e.g., a valve) is included in each of these venting paths.The vehicle is equipped with a refueling vent valve and a service vent valve, each of which can be opened and closed. In the event of unauthorized operation of the vehicle, the control unit closes all relevant electrically switchable valves (the control unit is designed accordingly), preventing air trapped in the fuel tank from escaping through any of the vent paths and thus rendering the vehicle unusable for refueling.

[0015] The invention is explained in more detail below by way of example and in a non-limiting manner with reference to the drawing. The features shown in the single figure and / or explained below can, even independently of specific combinations of features, be general features of the invention and further develop the invention accordingly. Fig.Figure 1 schematically shows a fuel supply system according to the invention for a motor vehicle with an internal combustion engine.

[0016] The fuel supply system 100 according to the invention comprises a fuel tank 110 for storing fuel K (e.g., gasoline or diesel fuel). A supply line 130 leads from the fuel tank 110 to the internal combustion engine of the motor vehicle. The fuel K is delivered to the internal combustion engine by a fuel pump, which may be installed in the fuel tank 110. Inside the fuel tank 110 is a reservoir 120. The fuel supply system 100 also comprises a filler pipe 140 opening into the fuel tank 110 or into the interior of the fuel tank 110, through which fuel K flows into the fuel tank 110 during refueling. The filler pipe 140 may have a filler neck for a fuel nozzle at its upper end.The fuel supply system 100 also includes a venting device 150 through which air L can escape from the fuel tank 110 during refueling via a vent line forming a vent path (refueling vent path) 151. A filter (e.g., an activated carbon filter) is typically located in the vent path 151. An electrically switchable valve 152 (refueling vent valve) is arranged in the vent path 151, which can be used to open and close the vent path 151. This vent valve 152 is directly controlled by a control unit 160.

[0017] The control unit 160 has a radio receiver 161 that can receive an externally transmitted theft detection signal. Upon receiving this signal, the control unit 160 switches the valve 152 to a closed position, preventing air L from escaping from inside the fuel tank 110 during refueling. The fuel K, which is poured into the filler pipe 140 at its upper end, rises in the filler pipe 140, causing a backup and ultimately shutting off the fuel nozzle or dispensing valve. Refueling is therefore impossible. Refueling using a jerrycan is also not possible.

[0018] The venting device 150 can have a further separate venting path for operational venting, as already explained above. In this case, it is intended that an electrically switchable valve (operational venting valve) is also arranged in this operational venting path, which is switched to a closed state by the control unit 160 in the event of theft of the motor vehicle (or other unauthorized use). Reference symbol list 100 Fuel supply system 110 fuel tank 120 storage pot 130 Lead line 140 filling nozzles 150 Ventilation device 151 Venting path 152 Valve 160 control unit 161 radio receivers K fuel L air

Claims

[1] Fuel supply system (100) for a motor vehicle with an internal combustion engine, comprising: - a fuel tank (110); - a filling pipe (140) leading into the fuel tank (110), through which fuel (K) flows into the fuel tank (110) during refueling; - a venting device (150) through which air (L) can escape from the fuel tank (110) via a venting path (151) during refueling, wherein at least one electrically switchable valve (152) is arranged in the venting path (151) with which the venting path (151) can be opened and closed; - a control unit (160) which, in the event of unauthorized operation of the motor vehicle, closes the electrically switchable valve (152), making refueling via the filler pipe (140) impossible. [2] Fuel supply system (100) according to claim 1, characterized by, that the electrically switchable valve (152) has a basic position in which it is closed. [3] Fuel supply system (100) according to claim 2, further comprising: - a relay controlled by the control unit (160) which, in the event of unauthorized operation of the motor vehicle, interrupts the power supply to the electrically switchable valve (152), so that the electrically switchable valve (152) switches to its closed basic position. [4] Fuel supply system (100) according to any one of the preceding claims, further comprising: - a theft detection device that detects a theft of the motor vehicle and informs the control unit (160) of the unauthorized operation of the motor vehicle. [5] Fuel supply system (100) according to any one of the preceding claims, further comprising: - a radio receiver (161) that receives an externally transmitted theft detection signal and informs the control unit (160) of the unauthorized operation of the motor vehicle. [6] Method for activating a refueling lock in a fuel supply system (100) according to any one of the preceding claims 1 to 5, comprising the steps: - Detection of unauthorized operation of the motor vehicle; - automatic closing of the electrically switchable valve (152) initiated by the control unit (160), making it impossible to refuel the fuel tank (110). [7] Motor vehicle with an internal combustion engine and a fuel supply system (100) according to any one of the preceding claims 1 to 5.

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