A fuel detection device

Abstract

The utility model relates to fuel detection technical field provides a kind of fuel detection device, including main controller and with its connection first measurement module, second measurement module, third measurement module and power supply switch module, and fuel sensor, coupling module, first detection switch module and second detection switch module;Based on fuel fault position, first measurement module, second measurement module, third measurement module are respectively set in power output node, the input / output node of fuel sensor, and then by setting 3-way detection voltage, according to each way detection voltage value can accurately judge fault type, to quickly locate fault, improve product overhaul efficiency and low in cost.

Description

Technical Field

[0001] This utility model relates to the field of fuel detection technology, and in particular to a fuel detection device. Background Technology

[0002] In automotive electronic control systems, fuel level detection is achieved by using a fuel level sensor (usually a sliding resistor type) built into the fuel pump assembly to convert the amount of fuel in the tank into a change in resistance value. This change is then processed into a voltage signal by a voltage divider circuit, and the ECU calculates the fuel level data.

[0003] However, because existing technologies mainly employ a single-point detection architecture that relies on a single sensor signal for liquid level determination, they cannot effectively distinguish the root cause of faults when abnormal phenomena such as signal over-limits or linearity distortion occur. The main causes of faults are as follows: (1) The liquid level sensor body fails, for example, the sensor resistive film is worn; (2) Harness connection failure, such as connector oxidation leading to increased contact resistance; (3) Abnormal signal processing circuit, such as drift of the reference voltage of the analog-to-digital converter.

[0004] Because of the lack of accurate diagnosis of the cause of the fuel level detection circuit failure, the repair process often relies on experience-based judgment and replacement of parts one by one, which is inefficient, costly, and carries the risk of misdiagnosis. Utility Model Content

[0005] This invention provides a fuel detection device that solves the technical problem that traditional single-point detection architecture cannot accurately locate faults, resulting in high difficulty and low efficiency in fault maintenance.

[0006] To solve the above technical problems, this utility model provides a fuel detection device, including a main controller and a first measurement module, a second measurement module, a third measurement module and a power supply switch module connected thereto, as well as a fuel sensor, a coupling module, a first detection switch module and a second detection switch module; The output terminal of the power supply switch module is connected to the coupling module and the first measurement module; the output terminal of the coupling module is connected to the fuel sensor and the second measurement module; and the output terminal of the fuel sensor is connected to the third measurement module. The first detection switch module is connected in parallel with the second measurement module, and the second detection switch module is connected in parallel with the third measurement module.

[0007] This basic solution is based on the location of fuel faults. It specifically sets up a first measurement module, a second measurement module, and a third measurement module at the power output node and the input / output node of the fuel sensor, respectively. By setting up three detection voltages, the fault type can be accurately determined based on the detection voltage values ​​of each channel, thereby quickly locating the fault, improving product repair efficiency, and reducing costs.

[0008] In a further embodiment, the power supply switch module includes a first switch Q1, a second switch Q2, a resistor R1, and a resistor R2; The control terminal of the first switch Q1 is connected to the main controller, the first terminal is connected to the control terminal of the second switch Q2 through resistor R1, and the second terminal is grounded. The first end of the second switch Q2 is connected to the coupling module and the first measurement module, and the second end is connected to the power input terminal; the two ends of the resistor R2 are respectively connected to the second end and the control terminal of the second switch Q2.

[0009] This solution uses a classic switching combination of transistor (first switching transistor Q1) and MOSFET (second switching transistor Q2) for power control. On the one hand, the transistor is responsible for small current control, and the drive circuit is simple. On the other hand, MOSFET is used as a power switch, which has low on-resistance and low power consumption, so as to achieve low cost, high efficiency electrical isolation and power drive, while also having high reliability.

[0010] In a further embodiment, the coupling module includes a resistor R3, one end of which is connected to the output terminal of the power supply switch module and the first measurement module, and the other end is connected to the fuel sensor, the second measurement module and the first detection switch module.

[0011] This solution uses a series coupling module between the first and second measurement modules. By monitoring the voltage change across the coupling resistor (i.e., resistor R3), it can accurately pinpoint whether the fault lies with the liquid level sensor itself or with the external wiring harness, thereby significantly improving the system's fault identification and diagnosis capabilities.

[0012] In a further embodiment, the first measurement module includes resistors R4 and R5; one end of resistor R4 is connected to the output terminal of the power supply switch module, and the other end is connected to the main controller; one end of resistor R5 is connected to the other end of resistor R4, and the other end is grounded.

[0013] This solution uses a voltage divider detection circuit consisting of resistors R4 and R5 at the power output node to directly monitor the power status of the main circuit. When the output is abnormal, it can quickly distinguish whether the fault is due to the power supply itself or a problem with the back-end sensor circuit. Online diagnosis can be achieved without disconnecting the main circuit, which significantly improves fault location efficiency and system maintainability.

[0014] In a further embodiment, the second measurement module includes resistors R6 and R7; one end of resistor R6 is connected between the coupling module and the fuel sensor, and the other end is connected to the main controller; one end of resistor R7 is connected to the other end of resistor R6, and the other end is grounded.

[0015] In a further embodiment, the first detection switch module includes a third switch tube Q3, the control terminal of which is connected to the main controller, the first terminal of which is connected between the coupling module and the fuel sensor, and the second terminal is grounded.

[0016] This solution is based on the traditional fuel level sensor's fuel detection principle. It further sets up a first detection switch module connected in parallel with the second measurement module. By turning the third switch Q3 on / off, it performs the fault location / fuel detection mode switching of the second measurement module. By comparing the output response in the two modes, it can accurately identify the specific fault source of the sensor, wiring harness or processing circuit. The structure is simple and the cost is low, which significantly enhances the system's online diagnostic capability.

[0017] In a further embodiment, the third measurement module includes resistors R8 and R9; one end of resistor R8 is connected between the second detection switch module and the fuel sensor, and the other end is connected to the main controller; one end of resistor R9 is connected to the other end of resistor R8, and the other end is grounded.

[0018] This solution features a multi-channel AD detection system with a first measurement module, a second measurement module, and a third measurement module, achieving triple redundancy detection of the power supply path. It is characterized by accurate fault location and strong anti-interference capability.

[0019] In a further embodiment, the second detection switch module includes a fourth switch tube Q4, the control terminal of which is connected to the main controller, the first terminal of which is connected between the third measurement module and the fuel sensor, and the second terminal is grounded.

[0020] This solution uses the conduction control of the switching transistor and, based on the first and second detection switching modules, measures the voltage system reference potential across the fuel sensor during fault detection. By acquiring the voltage sampling values ​​from the second and third measurement modules, it can determine whether there is a fuel passage fault. The fault detection principle is simple and the circuit cost is low.

[0021] In a further embodiment, the first switching transistor Q1 includes an NPN transistor or a PNP transistor.

[0022] In a further embodiment, the second switch Q2 includes a P-channel MOSFET or an N-channel MOSFET. Attached Figure Description

[0023] Figure 1 This is a system framework diagram of a fuel detection device provided in an embodiment of the present invention; Figure 2 This is provided by the embodiment of the present utility model. Figure 1 Hardware circuit diagram; The components include: main controller 1, first measurement module 2, second measurement module 3, third measurement module 4, power supply switch module 5, fuel sensor 6, coupling module 7, first detection switch module 8, and second detection switch module 9. Detailed Implementation

[0024] The embodiments of this utility model are described in detail below with reference to the accompanying drawings. The embodiments are given for illustrative purposes only and should not be construed as limiting the utility model. The accompanying drawings are for reference and illustration only and do not constitute a limitation on the scope of patent protection of this utility model, because many changes can be made to this utility model without departing from the spirit and scope of this utility model.

[0025] This utility model provides a fuel detection device, such as... Figure 1 Figure 2 As shown, in this embodiment, it includes a main controller 1 and a first measurement module 2, a second measurement module 3, a third measurement module 4 and a power supply switch module 5 connected thereto, as well as a fuel sensor 6, a coupling module 7, a first detection switch module 8 and a second detection switch module 9; The output terminal of the power supply switch module 5 is connected to the coupling module 7 and the first measurement module 2; the output terminal of the coupling module 7 is connected to the fuel sensor 6 and the second measurement module 3; and the output terminal of the fuel sensor 6 is connected to the third measurement module 4. The first detection switch module 8 is connected in parallel with the second measurement module 3, and the second detection switch module 9 is connected in parallel with the third measurement module 4.

[0026] Specifically, the main controller 1 uses three enable signals EN1, EN2, and EN3 to output corresponding control signals to the first measurement module 2, the second measurement module 3, and the third measurement module 4, respectively, to construct a synchronous control architecture.

[0027] Among them, the main controller 1 is a functional chip with data processing capabilities, such as an MCU.

[0028] In this embodiment, the power supply switch module 5 includes a first switch Q1, a second switch Q2, a resistor R1, and a resistor R2; The control terminal of the first switch Q1 is connected to the main controller 1, the first terminal is connected to the control terminal of the second switch Q2 through resistor R1, and the second terminal is grounded. The first end of the second switch Q2 is connected to the coupling module 7 and the first measurement module 2, and the second end is connected to the power input terminal; the two ends of the resistor R2 are respectively connected to the second end and the control terminal of the second switch Q2.

[0029] In this embodiment, the first switching transistor Q1 includes an NPN transistor or a PNP transistor.

[0030] In this embodiment, the second switch Q2 includes a P-channel MOSFET or an N-channel MOSFET. This embodiment uses a classic switching combination of a transistor (first switch Q1) and a MOSFET (second switch Q2) for power control. On the one hand, the transistor is responsible for small current control, and the drive circuit is simple; on the other hand, the MOSFET is used as a power switch, which has low on-resistance and low power consumption, so as to achieve low-cost, high-efficiency electrical isolation and power drive, while also having high reliability.

[0031] In this embodiment, the coupling module 7 includes a resistor R3. One end of the resistor R3 is connected to the output terminal of the power supply switch module 5 and the first measurement module 2, and the other end is connected to the fuel sensor 6, the second measurement module 3 and the first detection switch module 8.

[0032] In this embodiment, module 7 is coupled in series between the first measurement module 2 and the second measurement module 3. By monitoring the voltage change across the coupling resistor (i.e., resistor R3), the fault of the liquid level sensor itself or the external wiring harness can be accurately located, thereby significantly improving the system's fault identification and diagnosis capabilities.

[0033] In this embodiment, the first measurement module 2 includes resistors R4 and R5; one end of resistor R4 is connected to the output terminal of the power supply switch module 5, and the other end is connected to the main controller 1; one end of resistor R5 is connected to the other end of resistor R4, and the other end is grounded.

[0034] This embodiment uses a voltage divider detection circuit consisting of resistors R4 and R5 at the power output node to directly monitor the power status of the main circuit. When the output is abnormal, it can quickly distinguish whether the fault is due to the power supply itself or a problem with the back-end sensor circuit. Online diagnosis can be achieved without disconnecting the main circuit, which significantly improves fault location efficiency and system maintainability.

[0035] In this embodiment, the second measurement module 3 includes resistors R6 and R7; one end of resistor R6 is connected between the coupling module 7 and the fuel sensor 6, and the other end is connected to the main controller 1; one end of resistor R7 is connected to the other end of resistor R6, and the other end is grounded.

[0036] In this embodiment, the first detection switch module 8 includes a third switch tube Q3. The control terminal of the third switch tube Q3 is connected to the main controller 1, the first terminal is connected between the coupling module 7 and the fuel sensor 6, and the second terminal is grounded.

[0037] The third switch Q3 includes either an N-channel MOSFET or a P-channel MOSFET. In this embodiment, an N-channel MOSFET is preferred.

[0038] This embodiment is based on the traditional fuel level sensor's fuel detection principle. It further sets up a first detection switch module 8 connected in parallel with the second measurement module 3. By turning the third switch Q3 on / off, it performs the fault location / fuel detection mode switching of the second measurement module 3. By comparing the output response in the two modes, it can accurately identify the specific fault source of the sensor, wiring harness or processing circuit. The structure is simple and the cost is low, which significantly enhances the system's online diagnostic capability.

[0039] In this embodiment, the third measurement module 4 includes resistors R8 and R9; one end of resistor R8 is connected between the second detection switch module 9 and the fuel sensor 6, and the other end is connected to the main controller 1; one end of resistor R9 is connected to the other end of resistor R8, and the other end is grounded.

[0040] This embodiment designs a multi-channel AD detection system consisting of a first measurement module 2, a second measurement module 3, and a third measurement module 4, achieving triple redundancy detection of the power supply path. It features accurate fault location and strong anti-interference capabilities.

[0041] In this embodiment, the second detection switch module 9 includes a fourth switch tube Q4. The control terminal of the fourth switch tube Q4 is connected to the main controller 1, the first terminal is connected between the third measurement module 4 and the fuel sensor 6, and the second terminal is grounded.

[0042] The fourth switch Q4 includes either an N-channel MOSFET or a P-channel MOSFET. In this embodiment, an N-channel MOSFET is preferred.

[0043] This embodiment controls the conduction of the switching transistor. Based on the first detection switch module 8 and the second detection switch module 9, the voltage system reference potential across the fuel sensor 6 is measured during fault detection. By obtaining the voltage sampling values ​​of the second measurement module 3 and the third measurement module 4, it can be determined whether there is a fuel passage fault. The fault detection principle is simple and the circuit cost is low.

[0044] In this embodiment, the specific working principle is as follows: (1) Fault detection mode A) The main controller 1 simultaneously activates the EN1, EN2, and EN3 enable signals; At this time, the first switch Q1 and the second switch Q2 are turned on in sequence to provide the working voltage and form the main detection path.

[0045] At the same time, the third switch Q3 and the fourth switch Q4 are turned on, clamping the voltages V2 and V3 across the fuel sensor 6 to the system reference potential (e.g., ground level).

[0046] B) Obtain the sampling signals fed back by the first measurement module 2, the second measurement module 3, and the third measurement module 4.

[0047] The main controller 1 acquires the output voltage |V_AD1| of the first measurement module 2. When |V_AD1|>ΔV_th, a fault flag is triggered, indicating a main path fault.

[0048] The main controller 1 acquires the output voltages of the second measurement module 3 and the third measurement module 4. When |V_ADn|>ΔV_th of any channel, the corresponding branch is determined to be faulty.

[0049] Specifically, the voltage divider network configuration is as follows: AD2 channel: Resistors R6 and R7 (voltage division ratio k2 = R7 / (R6 + R7)) AD3 channel: Resistors R8 and R9 (voltage division ratio k3 = R9 / (R8 + R9)) Dual redundancy detection mechanism: a) AD2 monitoring: VDD→R3→R6→R7→GND pathway; b) AD3 monitoring: VDD→R3→R8→R9→GND pathway.

[0050] If |V_ADn-VDD×kn|>ΔV_th, the corresponding branch is determined to be faulty.

[0051] Diagnostic logic: If AD1 is abnormal, the main circuit is faulty; if AD2 or AD3 is abnormal, the fuel circuit is faulty. In the formula, ΔV_th is the preset voltage tolerance threshold, which needs to be set according to the specific circuit parameters.

[0052] (2) Fuel level detection mode Enable control: The main controller 1 activates the EN1 enable signal (high level) and disables the EN2 and EN3 enable signals (low level). At this time, the circuit enters the fuel detection working mode.

[0053] Voltage sampling path: 1) Reference voltage sampling: VDD power supply → via the second switch Q2 → through the resistor divider network of resistors R3, R6, and R7 → generates VAD2 reference voltage → input to the ADC1 channel of the main controller 1.

[0054] 2) Fuel sensor 6 sampling: VDD power supply → flows through the variable resistor of fuel sensor 6 → through the voltage divider circuit composed of resistors R8 and R9 → generates VAD3 detection voltage → input to the ADC2 channel of the MCU.

[0055] Fuel quantity calculation formula:

[0056] Finally, based on the fuel resistance value The system is converted according to a preset fuel quantity table, and the final fuel quantity value is displayed on the display module.

[0057] Based on the location of the fuel fault, this utility model embodiment specifically sets up a first measurement module 2, a second measurement module 3, and a third measurement module 4 at the power output node and the input / output node of the fuel sensor 6, respectively. By setting up three detection voltages, the fault type can be accurately determined based on the detection voltage values ​​of each channel, thereby quickly locating the fault, improving product maintenance efficiency, and reducing costs.

[0058] The above embodiments are preferred embodiments of the present utility model, but the embodiments of the present utility model are not limited to the above embodiments. Any changes, modifications, substitutions, combinations, or simplifications made without departing from the spirit and principle of the present utility model shall be considered equivalent substitutions and shall be included within the protection scope of the present utility model.

Claims

1. A fuel detection device, characterized in that: It includes a main controller and connected to it a first measurement module, a second measurement module, a third measurement module and a power supply switch module, as well as a fuel sensor, a coupling module, a first detection switch module and a second detection switch module; The output terminal of the power supply switch module is connected to the coupling module and the first measurement module; the output terminal of the coupling module is connected to the fuel sensor and the second measurement module; and the output terminal of the fuel sensor is connected to the third measurement module. The first detection switch module is connected in parallel with the second measurement module, and the second detection switch module is connected in parallel with the third measurement module.

2. The fuel detection device as described in claim 1, characterized in that: The power supply switch module includes a first switch Q1, a second switch Q2, a resistor R1, and a resistor R2; The control terminal of the first switch Q1 is connected to the main controller, the first terminal is connected to the control terminal of the second switch Q2 through resistor R1, and the second terminal is grounded. The first end of the second switch Q2 is connected to the coupling module and the first measurement module, and the second end is connected to the power input terminal; the two ends of the resistor R2 are respectively connected to the second end and the control terminal of the second switch Q2.

3. The fuel detection device as described in claim 1, characterized in that: The coupling module includes a resistor R3. One end of the resistor R3 is connected to the output terminal of the power supply switch module and the first measurement module, and the other end is connected to the fuel sensor, the second measurement module and the first detection switch module.

4. The fuel detection device as described in claim 1, characterized in that: The first measurement module includes resistors R4 and R5; one end of resistor R4 is connected to the output terminal of the power supply switch module, and the other end is connected to the main controller; one end of resistor R5 is connected to the other end of resistor R4, and the other end is grounded.

5. The fuel detection device as described in claim 4, characterized in that: The second measurement module includes resistors R6 and R7; one end of resistor R6 is connected between the coupling module and the fuel sensor, and the other end is connected to the main controller; one end of resistor R7 is connected to the other end of resistor R6, and the other end is grounded.

6. The fuel detection device as described in claim 5, characterized in that: The first detection switch module includes a third switch tube Q3. The control terminal of the third switch tube Q3 is connected to the main controller, the first terminal is connected between the coupling module and the fuel sensor, and the second terminal is grounded.

7. The fuel detection device as described in claim 1, characterized in that: The third measurement module includes resistors R8 and R9; one end of resistor R8 is connected between the second detection switch module and the fuel sensor, and the other end is connected to the main controller; one end of resistor R9 is connected to the other end of resistor R8, and the other end is grounded.

8. The fuel detection device as described in claim 7, characterized in that: The second detection switch module includes a fourth switch transistor Q4. The control terminal of the fourth switch transistor Q4 is connected to the main controller, the first terminal is connected between the third measurement module and the fuel sensor, and the second terminal is grounded.

9. A fuel detection device as described in claim 2, characterized in that: The first switching transistor Q1 includes an NPN transistor or a PNP transistor.

10. A fuel detection device as described in claim 2, characterized in that: The second switch Q2 includes a P-channel MOSFET or an N-channel MOSFET.

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