Sensor module for a vehicle and vehicle

Abstract

Sensor module (10) for a vehicle (50), comprising: a level sensor (14) for determining the level of a fluid in a tank (52); an ethanol sensor (22) for determining the ethanol content of the fluid; a substrate (12) on which the level sensor (14) and the ethanol sensor (22) are arranged; and an encapsulation arrangement, wherein the level sensor (14) has an ultrasound-based sensor element (15); wherein the ethanol sensor (22) has a capacitive sensor element (17); wherein the ultrasound-based sensor element (15) and the capacitive sensor element (17) are arranged on opposite sides (16, 18) of the substrate (12); and wherein the encapsulation arrangement together with the substrate (12) fluid-tight encloses the level sensor (14).

Description

[0001] The invention relates to a sensor module for a vehicle and a vehicle with such a sensor module. In particular, the invention relates to a sensor module for determining the fill level of a fluid in a vehicle's tank and for determining the ethanol content of the fluid.

[0002] Fuel supplied to a vehicle or its combustion engine is increasingly being mixed with higher proportions of ethanol, particularly to conserve existing fossil fuel resources.

[0003] A combustion process as well as an efficiency or effectiveness of the vehicle's combustion engine can depend on the proportion of ethanol, i.e. the ethanol content, in the fuel and / or on a mixing ratio of the ethanol to other components of the fuel.

[0004] Therefore, an ethanol sensor is usually provided in a vehicle's tank, for example, a fuel tank and / or an oil tank, which is designed to determine the ethanol content with a desired and / or required accuracy. Furthermore, a separate fill level sensor is usually provided in the fuel tank.

[0005] The publications DE 10 2008 013 530 A1, DE 10 2012 200 757 A1, DE 40 25 326 A1, and WO 91 / 08450 A1 relate to level sensors. The object of the invention is to provide a compact and cost-effective sensor module for a vehicle.

[0006] This problem is solved by the subject matter of the independent claim. Further advantageous embodiments emerge from the dependent claims.

[0007] According to one aspect of the invention, a sensor module for a vehicle is proposed. The sensor module comprises a fill level sensor for detecting and / or determining a fill level of a fluid in a tank and an ethanol sensor for detecting and / or determining an ethanol content of the fluid. Furthermore, the sensor module comprises a substrate on which the fill level sensor and the ethanol sensor are arranged.

[0008] In other words, the level sensor and the ethanol sensor are arranged on a common substrate. In particular, the level sensor and the ethanol sensor can be at least partially attached to the substrate, for example, by means of an adhesive bond, a soldered bond, and / or a welded bond. The level sensor and the ethanol sensor can be arranged on one side or surface or on different sides or surfaces of the substrate.

[0009] By arranging the fill level sensor and the ethanol sensor on a single substrate, a compact sensor module can be created that can implement the functions of level detection and ethanol content determination. This also reduces the cost of the sensor module. Maintenance and installation costs, for example, can also be reduced.

[0010] The tank can refer to a fuel tank, an oil tank and / or any other tank of the vehicle.

[0011] The fluid can refer, for example, to a fuel mixed with ethanol for operating a vehicle's internal combustion engine. The fluid can also refer, for example, to an oil-ethanol mixture or any other liquid mixed with ethanol.

[0012] The vehicle can be, for example, a motor vehicle such as a car, a bus or a truck, or a rail vehicle, a ship, or an aircraft such as a helicopter or an airplane.

[0013] According to one embodiment of the invention, the fill level sensor comprises an ultrasound-based sensor element. Alternatively or additionally, the fill level sensor is designed to determine the fill level by measuring the distance and propagation time of an ultrasonic signal. For example, a travel time can be determined by reflecting the ultrasonic signal off a surface of the fluid, and the fill level can be determined based on this travel time. Such ultrasound-based sensor elements can be distinguished in particular with regard to the reliability and accuracy of determining the fill level. If necessary, the fill level sensor can also comprise a sound-based sensor element.

[0014] According to one embodiment of the invention, the ethanol sensor comprises a capacitive sensor element. Alternatively or additionally, the ethanol sensor is designed to determine capacitive differences between ethanol and other components of the fluid. For this purpose, the capacitive sensor element can, for example, comprise a capacitor, with the aid of which a relative permittivity and / or an average dielectric constant of the fluid can be determined. Using known values ​​for the relative permittivity of ethanol, which has a value of approximately 24, as well as known values ​​for the relative permittivity of diesel and / or gasoline, which has a value of approximately 2.2, a mixing ratio of ethanol to other components of the fluid can be determined. Such capacitive sensor elements can be distinguished in particular with regard to the reliability and accuracy of determining the ethanol content.

[0015] According to one embodiment of the invention, the ethanol sensor comprises a capacitive sensor element with a meandering shape. Since the degree of mixing between ethanol and other components of the fluid is generally not completely homogeneous, an average value can be advantageously determined using the meandering capacitive sensor element. This advantageously increases the accuracy of determining the mixing ratio and thus the accuracy of determining the ethanol content.

[0016] According to one embodiment of the invention, the capacitive sensor element is arranged at least partially on an outer side of the substrate. Alternatively or additionally, the capacitive sensor element is designed to be at least partially in direct contact with the fluid. The external arrangement can, in particular, ensure that the capacitive sensor element is at least partially surrounded by the fluid, so that the ethanol content can be reliably determined.

[0017] The fill level sensor has an ultrasonic sensor element, and the ethanol sensor has a capacitive sensor element, wherein the ultrasonic sensor element and the capacitive sensor element are arranged on opposite sides of the substrate. Thus, the capacitive sensor element can be at least partially in direct contact with the fluid, whereas the ultrasonic sensor element arranged on the other side can be comprehensively protected against the influences of the fluid. The ultrasonic sensor element and / or the ethanol sensor can be designed and / or constructed to be fluid-resistant, in particular fuel-resistant. An arrangement on opposite sides can also be advantageous from a manufacturing perspective. Opposite sides or surfaces of the substrate can designate surfaces whose surface normal vectors run antiparallel to one another.

[0018] The sensor element has an encapsulation arrangement, wherein the encapsulation arrangement together with the substrate encloses the fill level sensor in a fluid-tight manner. The encapsulation arrangement can in particular comprise a cover which can be fastened to the substrate in a fluid-tight manner, for example by soldering, gluing and / or welding. Together with the substrate, the cover can completely enclose the fill level sensor so that it can be comprehensively protected against the fluid and can thus be designed and / or constructed to be fluid-resistant, in particular fuel-resistant. In other words, the sensor module according to the invention can be designed and / or constructed to be capacitive on one side, i.e. equipped with a capacitive sensor element, and encapsulated on one side, in particular completely encapsulated.

[0019] According to one embodiment of the invention, the sensor module comprises an electronic device arranged on the substrate for power supply and signal processing, wherein the electronic device comprises an ASIC (Application-Specific Integrated Circuit), a discrete electronic circuit, and / or a microcontroller. The electronic device can supply the ethanol sensor and / or the fill level sensor with electrical energy. The electronic device can further be configured to process signals from the fill level sensor and / or the ethanol sensor. The ASIC, the discrete circuit, and / or the microcontroller can be configured to process signals from both or only one of the sensor elements.

[0020] According to one embodiment of the invention, the substrate comprises ceramic material. In other words, the substrate can be a ceramic substrate. This can be particularly advantageous with regard to resistance, for example, to fluid influences, as well as with regard to mechanical strength.

[0021] A further aspect of the invention relates to a vehicle, in particular a motor vehicle with an internal combustion engine. The vehicle has a tank, such as a fuel tank, and a sensor module arranged at least partially in the tank, as described above and below.

[0022] Features and elements of the sensor module can be features and elements of the vehicle and vice versa.

[0023] The subject matter of the invention is explained below with reference to figures, without the subject matter of the invention being limited thereby. Fig. 1 shows schematically a cross section through a sensor module according to the invention. Fig. 2 shows a schematic plan view of a sensor module according to the invention. Fig. 3 schematically shows a cross section through a sensor module according to another embodiment of the invention. Fig. 4a to 4c each schematically show an electronic device for a sensor module according to embodiments of the invention. Fig. 5 schematically shows a motor vehicle with a sensor module according to an embodiment of the invention.

[0024] Identical and / or equivalent features and elements are provided with the same reference numerals in the figures.

[0025] Fig. 1 schematically shows a cross section through a sensor module 10 according to an embodiment of the invention.

[0026] The sensor module 10 has a substrate 12, which can be made of ceramic material, for example.

[0027] A fill level sensor 14 for determining the fill level of a fluid, such as a fuel, in a vehicle tank is arranged on a first side 16 or a first surface 16 of the substrate 12. The fill level sensor 14 can be attached, for example, by adhesive bonding, soldering, and / or welding, to the first side 16.

[0028] The fill level sensor 14 has an ultrasound-based sensor element 15 which is designed to generate an ultrasound signal so that the sensor module 10 and / or the fill level sensor 14 can determine the fill level of the fluid in the tank via a travel time measurement.

[0029] An ethanol sensor 22 for determining the ethanol content of the fluid is arranged on a second side 18 or a second surface 18 of the substrate 12. The ethanol sensor 18 can be attached, for example, by adhesive bonding, soldering, and / or welding, to the second side 22.

[0030] The ethanol sensor 22 has a capacitive sensor element 17 and is designed to determine capacitive differences between ethanol and other components of the fluid. For example, the capacitive sensor element 17 can designate and / or have a structure which can be printed, for example, on the second side 18 of the substrate 12. The structure and / or the capacitive sensor element 17 can in particular designate and / or have a capacitor, with the aid of which capacitive differences between a fuel, which can have a relative permittivity of around 2.2, and ethanol, which can have a relative permittivity of around 24, can be determined, determined, and / or measured. From this, an ethanol content in the fluid or fuel can then be determined. To increase the accuracy of determining the mixing ratio or the ethanol content, the capacitive sensor element 17 can be designed in a meandering shape.Furthermore, the capacitive sensor element 17 is arranged at least partially on the outside of the second side 18 of the substrate 12, so that it can be at least partially in direct contact with the fluid.

[0031] The ultrasonic-based sensor element 15 of the level sensor 14 and the capacitive sensor element 17 of the ethanol sensor 22 are mounted on opposite sides 16, 18 of the substrate 12. For example, the first side 16 can designate a front side and the second side 18 can designate a back side of the substrate 12. Further elements of the level sensor 14 or the ethanol sensor 22 can also be arranged on the corresponding first side 16 or the second side 18. The level sensor 14 can also be arranged entirely on the first side 16, and the ethanol sensor 22 can be arranged entirely on the second side 18.

[0032] Furthermore, the sensor module 10 of the Fig. 1 has an electronic device 24, which is arranged, for example, on the first side 16. Alternatively or additionally, the electronic device 24 or components of the electronic device 24 can be arranged on the second side 18. The electronic device 24 is designed and / or configured, in particular, to supply power to the fill level sensor 14 and / or the ethanol sensor 22. The electronic device 24 is also designed and / or configured to process signals from the fill level sensor 14 and / or the ethanol sensor 22. The electronic device 24 can, in particular, designate and / or comprise an electronic circuit.

[0033] Fig. Figure 2 schematically shows a top view of a sensor module 10 according to the invention. Shown is a top view of the second side 18 of the sensor module. Unless otherwise described, the sensor module 10 of the Fig. 2 the same elements and features as the sensor module 10 of the Fig. 1 on.

[0034] The capacitive sensor element 17 of the ethanol sensor 22 is shown as a capacitor by way of example and symbolically.

[0035] Furthermore, solder pads 19 for electrically contacting the sensor module 10 are arranged on the second side 18 of the substrate 12.

[0036] Fig. Figure 3 schematically shows a cross section through a sensor module 10 according to a further embodiment of the invention. Unless otherwise described, the sensor module 10 of the Fig. 3 the same elements and features as the sensor modules 10 of the Fig. 1 and Fig. 2 on.

[0037] The sensor module 10 of the Fig. 3 comprises an encapsulation arrangement for fluid-tightly enclosing the level sensor 14. The encapsulation arrangement comprises a cover 28, which is attached, for example, by means of a soldered connection, an adhesive connection, and / or a welded connection to the first side 16 of the substrate 12, such that the cover 28, together with the substrate 12, completely and fluid-tightly encloses the level sensor 14. The cover 28 can be made, for example, of aluminum, plastic, or another suitable material.

[0038] In this way, an existing encapsulated level measurement system can be replaced according to the invention with an ultrasound-based measurement system that uses the same encapsulation principle. An alternative fuel level sensor, i.e., fill level sensor 14, can also be used with a so-called flex-fuel sensor, i.e., an ethanol sensor 22, in a proven module with new, previously uncoupled measurement principles in the tank area.

[0039] Fig. 4a to 4c each schematically show an electronic device 24 for a sensor module 10 according to embodiments of the invention. Possible electronic architectures or configurations are shown.

[0040] The Fig. The electronic device 24 shown in Figure 4a includes a transducer 32 for generating an ultrasonic signal and a temperature sensor 34 for determining a temperature. Transducer 32, temperature sensor 34, and capacitive sensor element 17 are coupled and / or connected to an ASIC 30, which can be configured to supply power and / or process signals from capacitive sensor element 17.

[0041] In the Fig. 4b, the electronic device 24 has, in addition to the Fig. The components shown in Figure 4a comprise a discrete electronic circuit 37 with a memory 38 and a microcontroller 36. Measured values ​​of the capacitive sensor element 17 can be stored in the memory 38. The discrete electronic circuit 37 can, for example, perform excitation, amplification, and / or filtering of signals. Further signal processing is performed by the microcontroller 36.

[0042] Alternatively to further signal processing by means of microcontroller 36, as in Fig. 4b, further signal processing can be carried out with another controller or module 40, such as a fuel delivery controller, as shown in Fig. 4c shown.

[0043] Fig. Figure 5 schematically shows a motor vehicle 50 with a sensor module 10 according to an embodiment of the invention. Unless otherwise described, the sensor module 10 of the Fig. 5 have the same elements and features as the sensor modules 10 of the figures described above.

[0044] The motor vehicle 50 has a tank 52 in which the sensor module 10 is at least partially arranged. In particular, the sensor module 10 can be arranged entirely in the tank 52.

Claims

[1] Sensor module (10) for a vehicle (50), comprising: a level sensor (14) for determining a level of a fluid in a tank (52); an ethanol sensor (22) for determining an ethanol content of the fluid; a substrate (12) on which the level sensor (14) and the ethanol sensor (22) are arranged; and an encapsulation arrangement, wherein the level sensor (14) comprises an ultrasound-based sensor element (15); wherein the ethanol sensor (22) comprises a capacitive sensor element (17); wherein the ultrasound-based sensor element (15) and the capacitive sensor element (17) are arranged on opposite sides (16, 18) of the substrate (12); and wherein the encapsulation arrangement together with the substrate (12) encloses the fill level sensor (14) in a fluid-tight manner. [2] Sensor module (10) according to claim 1, wherein the level sensor (14) comprises an ultrasound-based sensor element (15); wherein the fill level sensor (14) is designed to determine the fill level by measuring the distance and transit time of an ultrasonic signal. [3] Sensor module (10) according to one of the preceding claims, wherein the ethanol sensor (22) comprises a capacitive sensor element (17); wherein the ethanol sensor (22) is designed to determine capacitive differences between ethanol and other components of the fluid. [4] Sensor module (10) according to one of the preceding claims, wherein the ethanol sensor (22) has a capacitive sensor element (17) which is formed in a meandering shape. [5] Sensor module (10) according to claim 4, wherein the capacitive sensor element (17) is arranged at least partially on an outer side (18) of the substrate (12); and / or wherein the capacitive sensor element (17) is designed to be at least partially in direct contact with the fluid. [6] Sensor module (10) according to one of the preceding claims, further comprising: an electronic device (24) arranged on the substrate (12) for power supply and signal processing, wherein the electronic device (24) comprises an ASIC (30), a discrete electronic circuit (37) and / or a microcontroller (36). [7] Sensor module (10) according to one of the preceding claims, wherein the substrate (12) comprises ceramic material. [8] Vehicle (50), comprising: a tank (52); and a sensor module (10) according to one of claims 1 to 7, arranged at least partially in the tank (52).

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