Fault detector of accelerator switch assembly and detection method thereof

Abstract

The invention discloses a fault detector of an accelerator switch assembly and a detection method thereof. The fault detector comprises at least one detection circuit. Each detection circuit comprises three constant current sources with equal output current, a first resistor and two voltage comparators; the input ends of the three constant current sources are used for inputting reference current; the output end of the first constant current source and the output end of the second constant current source are used for being connected with a normally-closed contact and a normally-open contact of an electric switch to be tested respectively, and the output end of the third constant current source is grounded through a first resistor. The common contact of the to-be-tested switch is grounded. Two input ends of the first voltage comparator are respectively connected with the output end of the first constant current source and the output end of the third constant current source; two input ends of the second voltage comparator are respectively connected with the output end of the second constant current source and the output end of the third constant current source; the output ends of the first voltage comparator and the second voltage comparator are used for outputting detection signals. According to the scheme, the detection efficiency and the detection precision of fault detection of the accelerator switch assembly can be greatly improved.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of aviation safety technology, in particular to a fault detector for a throttle switch assembly and a detection method thereof. BACKGROUND

[0002] The automatic throttle switch assembly is a frequently-fault component on the NG aircraft, including two switch assemblies M1766 and M1767, each of which has several groups of switches inside. The switch assembly failure often leads to multiple system failures of the aircraft, such as the anti-thrust system, brake system, PSEU system, and radar.

[0003] The M1766 and M1767 assemblies have a large number of switches inside, and it is complicated to measure the conduction state of each switch. When measuring, the personnel operating the throttle lever in the cockpit (M1766 or M1767 switch assembly is below the aircraft, but the rotation angle of the switch assembly needs to be confirmed on the CDU in the aircraft cockpit) also needs to be contacted at any time. Therefore, several maintenance personnel are required to work on the top and bottom of the aircraft with wired headsets to communicate and cooperate, which usually takes several hours to disassemble and assemble the components, find the corresponding plug pins, measure the circuit, and determine the fault point. The whole process is very cumbersome and prone to misjudgment, and the fault detection process is low in efficiency and accuracy. SUMMARY

[0004] To solve the above problems, the present application provides a fault detector for a throttle switch assembly and a detection method thereof, which can greatly improve the detection efficiency and accuracy of the throttle switch assembly fault detection.

[0005] The present application provides a fault detector for a throttle switch assembly, comprising at least one detection circuit;

[0006] Each detection circuit comprises three constant current sources with equal output current, a first resistor, and two voltage comparators;

[0007] The input ends of the three constant current sources are used to input reference current;

[0008] The output end of the first constant current source is used to connect the normally closed contact of the switch to be measured in the throttle switch assembly, the output end of the second constant current source is used to connect the normally open contact of the switch to be measured, and the output end of the third constant current source is connected to the ground through the first resistor; the common contact of the switch to be measured is grounded;

[0009] The two input ends of the first voltage comparator are connected to the output ends of the first and third constant current sources respectively; the two input ends of the second voltage comparator are connected to the output ends of the second and third constant current sources respectively; and the output ends of the first and second voltage comparators are used to output detection signals.

[0010] Preferably, each detection circuit further comprises two indicating devices;

[0011] The two indicating devices output different indicating light signals according to the levels of the detection signals output by the first voltage comparator and the second voltage comparator respectively.

[0012] Preferably, each indicating device comprises two current-limiting resistors, two indicating lights of different colors and a NAND gate.

[0013] The input end of the NAND gate is connected to the output end of the corresponding voltage comparator.

[0014] The input end of the NAND gate is connected to the input end of the first indicating light through the first current-limiting resistor, the output end of the NAND gate is connected to the input end of the second indicating light through the second current-limiting resistor, and the output ends of the first indicating light and the second indicating light are grounded.

[0015] Preferably, each indicating device comprises a current-limiting resistor, a light-emitting diode and a switch tube.

[0016] The input end of the switch tube is connected to a voltage source, the control end of the switch tube is connected to the output end of the corresponding voltage comparator, and the output end of the switch tube is grounded through the current-limiting resistor and the light-emitting diode.

[0017] Preferably, the number of detection circuits is the same as the number of accelerator levers to be detected in the accelerator lever assembly.

[0018] Each detection circuit is used to detect one of the accelerator levers in the accelerator lever assembly.

[0019] Preferably, the output end of the first constant current source in each detection circuit is connected to the same-phase input end of the input end of the first voltage comparator, and the output end of the second constant current source is connected to the same-phase input end of the input end of the second voltage comparator.

[0020] Preferably, each detection circuit further comprises a first contact for plugging connection with the normally closed contact.

[0021] Each detection circuit further comprises a second plug for plugging connection with the normally closed contact.

[0022] Each detection circuit further comprises a third plug for plugging connection with the common contact.

[0023] The first plugs, the second plugs and the third plugs of all the detection circuits are concentrated into a plug array.

[0024] Preferably, the indicating lights of the indicating devices of all the detection circuits are arranged in an array.

[0025] The embodiment of the present application also provides a detection method of the fault detector of the accelerator switch assembly, which is suitable for the fault detector of any of the above-mentioned accelerator switch assemblies, and the method comprises the following steps:

[0026] The output end of the first constant current source is connected with the normally closed contact of the to-be-detected switch, and the output end of the second constant current source is connected with the normally open contact of the to-be-detected switch;

[0027] The detection signals output by the output ends of the first voltage comparator and the second voltage comparator are recorded as first detection data;

[0028] The normally open / normally closed state of the to-be-detected switch is switched, and the detection signals output by the output ends of the first voltage comparator and the second voltage comparator are recorded as second detection data;

[0029] Whether the to-be-detected switch is faulty is determined according to the first detection data and the second detection data.

[0030] Preferably, whether the to-be-detected switch is faulty is determined according to the first detection data and the second detection data, and the determination comprises the following steps:

[0031] When the two detection signals in the first detection data are inconsistent, and the two detection signals in the second detection data are flipped compared with the first detection data, it is determined that the to-be-detected switch is not faulty;

[0032] When the two detection signals in the first detection data are consistent, or the two detection signals in the second detection data are not flipped compared with the first detection data, it is determined that the to-be-detected switch is faulty

[0033] The present application provides a fault detector of an accelerator switch assembly and a detection method thereof, which comprises at least one detection circuit; each detection circuit comprises three constant current sources with equal output currents, a first resistor and two voltage comparators; the input ends of the three constant current sources are used for inputting reference currents; the output end of the first constant current source is used for connecting the normally closed contact of a to-be-detected switch in the accelerator switch assembly, the output end of the second constant current source is used for connecting the normally open contact of the to-be-detected switch, and the output end of the third constant current source is connected to the ground through the first resistor; the common contact of the to-be-detected switch is connected to the ground; the two input ends of the first voltage comparator are connected to the output end of the first constant current source and the output end of the third constant current source respectively; the two input ends of the second voltage comparator are connected to the output end of the second constant current source and the output end of the third constant current source respectively; and the output ends of the first voltage comparator and the second voltage comparator are used for outputting detection signals. The present application can greatly improve the detection efficiency and detection accuracy of the fault detection of the accelerator switch assembly. BRIEF DESCRIPTION OF DRAWINGS

[0034] Figure 1 is a structural schematic view of a fault detector of a throttle lever assembly provided by an embodiment of the present application;

[0035] Figure 2 is another structural schematic view of a fault detector of a throttle lever assembly provided by an embodiment of the present application;

[0036] Figure 3 is still another structural schematic view of a fault detector of a throttle lever assembly provided by an embodiment of the present application;

[0037] Figure 4 is a flowchart of a detection method of a fault detector of a throttle lever assembly provided by an embodiment of the present application. DETAILED DESCRIPTION

[0038] The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all the embodiments of the present application. Based on the embodiments in the present application, all other embodiments obtained by a person of ordinary skill in the art without creative effort fall within the protection scope of the present application.

[0039] The M1766 and M1767 lever assemblies each include 9 micro-lever assemblies. The conventional inspection method is to measure the on state of each lever of the M1766 or M1767 lever assembly by using a multimeter once a related fault occurs. Since the number of levers in the assembly is large, the work of measuring the on state of each lever under the airplane is complex. The personnel operating the throttle lever in the cockpit (the M1766 or M1767 lever assembly is under the airplane, but the rotation angle of the lever assembly needs to be confirmed on the CDU in the cockpit of the airplane) also needs to be contacted at any time during the measurement. Therefore, several maintenance personnel need to be contacted and work together on the top and bottom of the airplane by using wired earphones every time the maintenance work involving the M1766 and M1767 is performed. It usually takes several hours to disassemble and assemble the parts, find the corresponding plug pins, measure the circuit, and determine the fault point. The whole process is very tedious. If the multimeter pen and the plug pins of the airplane electric plug are not in good contact or are shaken during the measurement, the measurement may not be accurate, which affects the judgment of the troubleshooting direction.

[0040] In view of the above technical problems, an embodiment of the present application provides a fault detector of a throttle lever assembly, which comprises a detection circuit.

[0041] Each detection circuit comprises three constant current sources with equal output currents, a first resistor, and two voltage comparators.

[0042] The input ends of the three constant current sources are used to input a reference current.

[0043] The output end of the first constant current source is used for connecting the normally closed contact of the accelerator pedal switch component to be detected, the output end of the second constant current source is used for connecting the normally open contact of the accelerator pedal switch component to be detected, and the output end of the third constant current source is grounded through the first resistor.

[0044] The two input ends of the first voltage comparator are respectively connected with the output end of the first constant current source and the output end of the third constant current source, the two input ends of the second voltage comparator are respectively connected with the output end of the second constant current source and the output end of the third constant current source, and the output ends of the first voltage comparator and the second voltage comparator are used for outputting detection signals.

[0045] In the specific implementation of the embodiment, referring to Figure 1 FIG. 1 is a structural schematic diagram of a fault detection instrument for an accelerator pedal switch component provided by an embodiment of the present application, which comprises:

[0046] The core of the accelerator pedal switch component fault detection instrument is to realize accurate judgment on the state of the switch contact through a detection circuit, and the design is based on the cooperative work of a constant current source circuit and a voltage comparator, and the specific component functions are as follows:

[0047] Three constant current sources, namely a first constant current source CA1, a second constant current source CA2 and a third constant current source CA3, output equal currents, and the current value is I, the input end receives a reference current V+, and the stability of the output current is ensured to provide a reference for detection.

[0048] The output end of the first constant current source is connected with the normally closed contact NC of the switch to be detected, and the current flows to the common contact ground through the normally closed contact.

[0049] The output end of the second constant current source is connected with the normally open contact NO of the switch to be detected, and the current flows to the common contact ground through the normally open contact.

[0050] The output end of the third constant current source is grounded through the first resistor R1, and the current path is: the third constant current source, the first resistor R1 and the ground end.

[0051] The common contact S1 is grounded to ensure that all current loops form a closed path and provide a zero potential reference for voltage comparison.

[0052] The first resistor (the resistance value is R) is connected with the third constant current source in series and then grounded to form a reference voltage reference point. The common contact of the switch to be detected is directly grounded to form a circuit reference potential.

[0053] The two voltage comparators are respectively used for comparing voltage signals of different branches, and the detection signals at the output ends can reflect the on-off state of the switch contact.

[0054] The third constant current source is grounded through the first resistor R, and the voltage generated across the resistor is: VREF = I x R1, the voltage as the two voltage comparators reference value.

[0055] The resistance of the first resistor R is usually set to 1 ohm.

[0056] One end of the input terminal of the first voltage comparator IC1 is connected to the output terminal of the first constant current source, i.e. the potential of the normally closed contact NC, and the other end is connected to the output terminal of the third constant current source, i.e. the reference voltage V REF .

[0057] One end of the input terminal of the second voltage comparator IC2 is connected to the output terminal of the second constant current source, i.e. the potential of the normally open contact NO, and the other end is connected to the output terminal of the third constant current source, i.e. the reference voltage V REF .

[0058] The electric door of M1766 / M1767, when each electric door is normally closed, the contact resistance should be less than 1 ohm; if the contact is poor or ablated, the on-resistance will be greater than 1 ohm. Each group of electric door corresponding test circuit unit has three constant current sources, and the current values of the three constant current sources are equal;

[0059] When the common contact and the normally closed contact are closed, the first constant current source current passes through the normally closed contact NC to ground; when the normally closed contact is normal, the resistance of the contact is less than 1 ohm, at this time the potential at the normally closed contact NC is less than the reference voltage V REF , at this time the input voltage of the first comparator is compared with V REF , and the output is low, indicating that the normally closed contact is normally closed. If the normally closed contact has poor contact or ablation, the on-resistance will be greater than 1 ohm, at this time the potential at the normally closed contact NC is greater than the reference voltage V REF , at this time the input voltage of the first comparator is compared with V REF , and the output is high, indicating that the normally closed contact is faulty. At this time, the common contact and the normally open contact are disconnected, at this time the potential at the normally open contact NO is also greater than the reference voltage V REF , at this time the input voltage of the second comparator is compared with V REF , and the output is high, indicating that the normally open contact is disconnected.

[0060] When the common contact and the normally open contact are closed, the second constant current source current passes through the normally open contact NO to ground, and when the normally closed contact is normal, the resistance of the contact is less than 1 ohm, at this time the potential at the normally open contact NO is less than the reference voltage V REF , at this time the input voltage of the second comparator is compared with V REF , and the output is low, indicating that the normally open contact NO is normally closed. If the normally open contact has poor contact or ablation, the on-resistance will be greater than 1 ohm, at this time the potential at the normally open contact NO is greater than the reference voltage V REF , at this time the input voltage of the second comparator is compared with V REFComparing, output high level, indicating the normally open contact fault. At this time, the common contact is disconnected with the normally closed contact, at this time, the normally closed contact NC end potential is also greater than the reference voltage V REF At this time, the first comparator input end voltage is V REF Comparing, output high level, indicating the normally closed contact is disconnected.

[0061] It should be noted that the first resistance value is set according to the normal conduction resistance of the contact in the embodiment, and the first resistance is generally an accurate resistance.

[0062] When the accelerator is in a specific working state (for example, the normally closed contact is closed when the accelerator is not stepped on, and the normally open contact is closed after stepping on), the corresponding comparator should output low level, indicating that the contact is in good contact.

[0063] If the comparator outputs high level, it indicates that the corresponding contact is not closed or there is an abnormality.

[0064] The constant current ensures the stability of the reference voltage on the resistance R, avoids the influence of power supply fluctuation or load change on detection accuracy, and makes the voltage comparison result only depend on the on-off state of the contact.

[0065] Since the connection state of different accelerators is not determined when the accelerator assembly is used, that is, the common contact is connected with the normally open contact or the normally closed contact, only one of them is connected. Therefore, when the two contacts are normal, the detection signals output from the output ends of the first voltage comparator and the second voltage comparator should be different, and the accelerator state can be determined through the output detection signals. In addition, by switching the connection state of the accelerator, the detection signals output from the output ends of the first voltage comparator and the second voltage comparator should be the same, so that whether the accelerator is faulty can be quickly identified.

[0066] Through the basic principle of current-voltage conversion and comparison, the on-off state of the mechanical contact is converted into an electrical signal output, and automatic fault detection of the accelerator assembly is realized.

[0067] In another embodiment provided by the application, two indicating devices are further included.

[0068] The two indicating devices respectively output different indicating lamp signals according to the levels of the detection signals output by the first voltage comparator and the second voltage comparator.

[0069] In the specific implementation of the embodiment, each detection circuit further includes two indicating devices; the two indicating devices convert the electrical signals into indicating lamp signals that can be directly recognized by people by receiving the output signals (high / low level) of the voltage comparator. This design realizes the visualization of the fault detection result, and greatly improves the usability of the system.

[0070] The first indicating device is connected to the output end of the first voltage comparator and reflects the state of the normally closed contact (NC).

[0071] The second indicating device is connected to the output end of the second voltage comparator and reflects the state of the normally open contact (NO).

[0072] The indicator light signal is usually a double-color LED (such as red / green) or a multi-lamp combination, which indicates the normal / fault of the contact through different colors or on / off states.

[0073] The indicating device is essentially a level-driven signal conversion circuit.

[0074] When the comparator output is low (corresponding to the normal state of the closed contact), the indicating device drives the green LED to light (or the red LED to be off), indicating "normal".

[0075] As an embodiment, the circuit implementation usually uses a transistor or MOSFET as a switch, which is turned on at low level, and the green LED loop is connected.

[0076] When the comparator output is high (corresponding to the fault state of the open contact), the indicating device drives the red LED to light (or the green LED to be off), indicating "fault". The high level makes the switching element cut off, switching to the red LED loop.

[0077] The detection circuit and the indicating device are integrated on the same circuit board to optimize the wiring to reduce interference. And an indicator light window is opened on the equipment panel, marked as "normally closed contact state" and "normally open contact state".

[0078] Through the design of the indicating device, the accelerator pedal assembly fault detector realizes a closed loop from electrical signal detection to visual feedback, significantly improving the practicability and reliability of the system.

[0079] In another embodiment provided by the application, each indicating device includes two current-limiting resistors, two color-indicating lights, and a NAND gate.

[0080] The input end of the NAND gate is connected to the output end of the corresponding voltage comparator.

[0081] The input end of the NAND gate is connected to the input end of the first indicating light through the first current-limiting resistor, the output end of the NAND gate is connected to the input end of the second indicating light through the second current-limiting resistor, and the output ends of the first and second indicating lights are grounded.

[0082] In the specific implementation of this embodiment, the indicating device converts the electrical signal of the voltage comparator into visual light indication through hardware logic, which is composed of a NAND gate, current-limiting resistors, and double-color indicating lights, as shown in Figure 2Fig. 2 is another structural schematic diagram of the fault detector of the accelerator switch assembly provided in the embodiment of the present application, and the specific connection relationship is as follows:

[0083] The NOT gate is used for negating the comparator output signal, so that the states of the two indicator lamps are mutually exclusive (one is on while the other is off).

[0084] The current-limiting resistor is used for limiting the current flowing through the indicator lamp, so as to prevent overcurrent damage to the LED.

[0085] The dual-color indicator lamp can intuitively distinguish the two states (normal / fault, closed / open) of the switch through different colors (such as red / green, red / yellow).

[0086] The high level (such as 5V) of the voltage comparator output indicates that the switch contact is open or the switch contact is open, and the low level (such as 0V) of the voltage comparator output indicates that the contact is closed. Correspondingly, the first indicator lamp (red lamp) indicates that the switch is abnormal or the switch contact is open, and the second indicator lamp (green lamp) indicates that the switch is normal.

[0087] When the comparator output is high, the input end of the NOT gate is high, and the output end of the NOT gate is low. A path is formed through the first current-limiting resistor and the red lamp grounding, and the red lamp is on. The output end of the NOT gate is low, and the green lamp is off. At this time, the green lamp of the indication device is off, and the red lamp is on, indicating that the switch contact is abnormal or the switch contact is open.

[0088] When the comparator output is low, the input end of the NOT gate is low, and the red lamp is off. The output end of the NOT gate is high, a path is formed through the second current-limiting resistor and the green lamp grounding, and the green lamp is on. At this time, the green lamp of the indication device is on, and the red lamp is off, indicating that the switch contact is normally closed.

[0089] It should be noted that the color combination of the indicator lamp can select two indicator lamps of different colors. It is recommended to use the international standard, that is, green represents normal and red represents fault. High-brightness SMD LEDs are preferably used to reduce power consumption and volume.

[0090] Through the two indicator lamps of different colors, the state of the switch can be quickly judged through the light color without the aid of instruments, and the fault troubleshooting time is shortened.

[0091] In another embodiment provided in the present application, each indication device includes a current-limiting resistor, a light-emitting diode, and a switch tube.

[0092] The input end of the switch tube is used for connecting a voltage source, the control end of the switch tube is used for connecting the output end of the corresponding voltage comparator, and the output end of the switch tube is grounded through the current-limiting resistor and the light-emitting diode.

[0093] In the embodiment, as the parallel embodiment of the previous embodiment, the indicating device can control the on-off of the light-emitting diode (LED) through the switch tube (such as a triode or MOSFET) to convert the electrical signal of the voltage comparator into light indication:

[0094] The switch tube serves as an electronic switch and controls the on-off of the circuit according to the level signal output by the comparator, such as a triode working in the saturation / cutoff region or a MOSFET working in the on / off region.

[0095] The current-limiting resistor limits the current flowing through the LED to prevent overcurrent damage.

[0096] Light-emitting diode (LED): directly display the state of the electric door through the light-emitting state (on / off).

[0097] As an example, the switch tube is an NPN triode, the high level output by the comparator indicates that the electric door contact is disconnected or faulty, and the low level output indicates that the contact is normally closed, and the working process is as follows:

[0098] When the comparator outputs a high level, the control end of the switch tube inputs a high level: if it is a triode, the base voltage is higher than the emitter, and the triode enters the saturation conduction state, and the collector and the emitter are connected.

[0099] The current path is formed by the voltage source, the output end of the switch tube, the current-limiting resistor, the LED, and the ground to form a loop, and the LED is lit.

[0100] When the comparator outputs a low level, the control end of the switch tube inputs a low level, the base voltage of the triode is insufficient, and the triode enters the cutoff state, and the collector and the emitter are disconnected. The current path is disconnected, and the LED has no current passing through and is in an off state.

[0101] It should be noted that if the switch tube uses a PNP tube or a P-channel MOSFET, the switching logic is opposite to that of the NPN type (the switch is turned on when the comparator outputs a low level and is turned off when the comparator outputs a high level), and the type of device needs to be selected according to the actual needs. The on / off state of the switch tube can be flexibly matched with the output level of the comparator without the need for additional logic gates.

[0102] It should be noted that the specific principles of the indicating device indicated in the present application are only two examples, and in the specific implementation of the scheme, those skilled in the art can design a suitable structure of the indicating device based on the basic principles, and the specific use of the indicating device does not affect the specific implementation of the present application.

[0103] In another embodiment provided by the present application, the number of detection circuits is the same as the number of electric doors to be detected in the accelerator electric door assembly.

[0104] Each detection circuit is used to detect one electric door to be detected in the accelerator electric door assembly.

[0105] In the specific implementation of the embodiment, the number of detection circuits is the same as the number of accelerator pedals to be detected in the accelerator pedal assembly.

[0106] Each detection circuit is used to detect one accelerator pedal to be detected in the accelerator pedal assembly.

[0107] In the specific implementation of the embodiment, the fault detector of the accelerator pedal assembly adopts the architecture that one detection circuit corresponds to one accelerator pedal to be detected, and the synchronous monitoring of the states of multiple accelerator pedals is realized through parallel detection.

[0108] The number of detection circuits is the same as the number of accelerator pedals to be detected in the accelerator pedal assembly, each detection circuit works independently, and the normally closed (NC) and normally open (NO) contacts of one accelerator pedal are detected. The state data of all accelerator pedals can be obtained at the same time, the time delay of serial detection is avoided, and the architecture is suitable for the scene that needs to monitor multiple accelerator pedals working in coordination in real time.

[0109] Taking the ith detection circuit as an example, the working principle thereof is the same as the constant current source and voltage comparator architecture described in the above embodiment.

[0110] Three constant current sources (the normally closed contact, the normally open contact of the accelerator pedal to be detected, and the reference resistor are supplied with power respectively. The voltage of the normally closed contact, the voltage of the normally open contact, and the reference voltage of the first resistor are compared through the corresponding voltage comparators.

[0111] The first voltage comparator outputs the state of the normally closed contact. The high level indicates an abnormality or disconnection, and the low level indicates normality and closure.

[0112] The second voltage comparator outputs the state of the normally open contact. The high level indicates an abnormality or disconnection, and the low level indicates normality and closure.

[0113] The input ends of the constant current sources of all detection circuits are connected in parallel to the same reference current source, so as to ensure that the detection references of the circuits are consistent and avoid misjudgment caused by current fluctuation.

[0114] The common contacts of all accelerator pedals to be detected are grounded, so as to form a unified reference potential.

[0115] The output ends of the comparators of each detection circuit are electrically isolated through an optocoupler or an isolation operational amplifier, so as to prevent interference between circuits (for example, the failure of a certain circuit does not affect other circuits).

[0116] If a data acquisition module (such as an MCU) is configured in the system, the output levels of all comparators are synchronously read through a multi-channel ADC, so as to realize real-time recording of the states of multiple accelerator pedals.

[0117] M1766 / M1767 each has 9 groups of electric doors, 9 groups of electric doors corresponding 18-way comparator circuit output to 18 red-green double-color LED, under normal circumstances, each electric door corresponding 2 red-green double-color LED is red and green, when the electric door appears closed contact resistance greater than 1 ohm abnormal situation, each electric door corresponding 2 red-green double-color LED will appear two red display. Through 18 double-color LED display red or green can directly see 9 groups of electric doors 18 pairs of contacts when the closing resistance is less than 1 ohm, compared with the method of using multimeter measurement or 9 groups of electric doors one by one, the measurement efficiency is greatly improved, and the man-machine engineering is good.

[0118] The scheme is suitable for complex throttle electric door assembly (such as containing main electric door, idling electric door, boost electric door and the like multiple sub-electric doors), and can feed back the contact state of each electric door in real time, so that the overall control failure caused by single electric door failure is avoided. If the number of to-be-tested electric doors needs to be increased, the newly added detection circuit only needs to be connected in parallel, and the core architecture does not need to be modified, so that the scheme is suitable for the development of universal detection equipment of different models of throttle electric door assemblies.

[0119] In another embodiment provided in the application, the output end of the first constant current source in each detection circuit is connected to the input end of the first voltage comparator and the output end of the second constant current source is connected to the input end of the second voltage comparator, which are both same-phase input ends.

[0120] In the specific implementation of the embodiment, the output currents of the three constant current sources (first, second and third) are equal (I), the third constant current source is connected to the ground through the first resistor R, and thus the voltage generated across the resistor by the third constant current source is V ref = I x R1, which is used as the reference voltage of the two voltage comparators.

[0121] The output end of the first constant current source is connected to the normally closed contact of the to-be-tested electric door, and the voltage signal thereof is connected to the positive-phase input end of the first voltage comparator;

[0122] The output end of the second constant current source is connected to the normally open contact of the to-be-tested electric door, and the voltage signal thereof is connected to the positive-phase input end of the second voltage comparator;

[0123] It should be noted that the output end of the first constant current source is connected to the input end of the first voltage comparator and the output end of the second constant current source is connected to the input end of the second voltage comparator, which are both same-phase input ends, positive phase or negative phase, so as to keep the homogeneity of the detection results of the detection signals finally output by the multiple detection circuits, ensure subsequent reading and efficient analysis, and be beneficial to subsequent indication by the indicating device, so that the user can quickly analyze the fault.

[0124] 9-way low resistance dynamic scanning measurement circuit can complete the inspection of 9 electric doors NC (normally closed), NO (normally open) 18 pairs of contact resistance conduction at the same time, compared with the traditional method of taking a multimeter probe to measure 9 electric doors one by one, avoid the artificial error caused by poor contact of multimeter probe and plug, improve the inspection accuracy, also greatly improve the inspection efficiency, can test the closing-open of electric door in a short time, find the hidden contact problem of some electric door.

[0125] In yet another embodiment provided by the application, each detection circuit further comprises a first contact for plugging with the normally closed contact;

[0126] Each detection circuit further comprises a second plug for plugging with the normally closed contact;

[0127] Each detection circuit further comprises a third plug for plugging with the common contact;

[0128] The first plug, the second plug and the third plug of all detection circuits are concentrated into a plug array.

[0129] In the specific implementation of the embodiment, the correspondence between the plug and the electric door contact includes

[0130] The first plug is plugged with the normally closed contact of the electric door to be tested, and is used for detecting the on-off state signal of the normally closed contact; the second plug is plugged with the normally open contact of the electric door to be tested, and is used for detecting the on-off state signal of the normally open contact; and the third plug is plugged with the common contact of the electric door to be tested, and is used as a common reference ground or a signal loop node of the circuit.

[0131] The first plug, the second plug and the third plug of all detection circuits are concentrated into a plug array, which is connected to the contact array of the accelerator pedal assembly through a unified interface to form a batch electrical connection. Figure 3 is another structural schematic view of the fault detector of the accelerator pedal assembly provided by the embodiment of the application.

[0132] The fault detector of the accelerator pedal assembly

[0133] The plug array is deployed on the mainboard of the detection circuit, each electric door corresponds to a group of (three) plugs (first, second and third plugs), and the plug pins are welded to the constant current source and the voltage comparator input end of the detection circuit; the contact end of the accelerator pedal assembly is designed as a socket matched with the plug array, and the normally closed contact, the normally open contact and the common contact correspond to the specified interface of the socket, respectively.

[0134] The plug array is inserted into the socket of the accelerator pedal assembly, so that the first plug is electrically connected with the normally closed contact, the second plug is electrically connected with the normally open contact, and the third plug is electrically connected with the common contact;

[0135] After the detection circuit is powered on, the constant current source detects the contact state through the plug loop, the voltage comparator outputs a corresponding level signal, and the indicating device is driven to display the result.

[0136] When the electric door or detection circuit needs to be repaired, the plug array is directly pulled out to achieve physical separation of the detection system and the electric door assembly, facilitating separate troubleshooting.

[0137] In specific implementation, different plug arrays are arranged for M1766 and M1767 respectively, facilitating rapid connection. Since the contacts of the common end of the M1766 and M1767 electric doors are grounded in implementation, only the normally open contacts and the normally closed contacts of the nine electric door assemblies need to be connected through two plug arrays in implementation; based on the difference in the contact conduction resistance of M1766 and M1767, the first resistor can be a variable resistor, and the resistance value of the first resistor is modified through a threshold resistance selection switch, so that the resistance value of the contact conduction resistance of M1766 and M1767 is accurately matched, and rapid fault detection can be achieved.

[0138] In yet another embodiment provided by the application, the indicator lights of the indicating devices of all detection circuits are arranged in an array.

[0139] In specific implementation of the embodiment, refer to Figure 3 , the display panel includes a power switch and a power indicator LED.

[0140] The 18 double-color LEDs corresponding to the S1-S9 electric doors are arranged in a 2x9 array, and the 18 comparator circuit outputs drive 18 red-green double-color LEDs corresponding to the 9 groups of electric doors. Under normal circumstances, the two red-green double-color LEDs corresponding to each electric door are red and green, and when the electric door contact resistance is greater than 1 ohm, the two red-green double-color LEDs corresponding to each electric door will display two red. By displaying red or green through the 18 double-color LEDs, it can be directly observed whether the conduction resistance of the 18 pairs of contacts of the 9 groups of electric doors is less than 1 ohm, and the measurement efficiency is greatly improved compared with the method of using a multimeter to measure or measuring the 9 groups of electric doors one by one, and the man-machine engineering is good.

[0141] Another embodiment of the application provides a detection method of a fault detector for an accelerator electric door assembly, which is applicable to the fault detector for the accelerator electric door assembly of any of the above embodiments, and refers to Figure 4 , which is a flowchart of the detection method of the fault detector for the accelerator electric door assembly provided by the embodiment of the application, and the method comprises the following steps:

[0142] Step S1, connecting the output end of the first constant current source with the normally closed contact of the electric door to be tested, and connecting the output end of the second constant current source with the normally open contact of the electric door to be tested;

[0143] Step S2, record the detection signals output by the output ends of the first voltage comparator and the second voltage comparator as first detection data;

[0144] Step S3, switch the normally open / closed state of the to-be-tested electric door, and record the detection signals output by the output ends of the first voltage comparator and the second voltage comparator as second detection data;

[0145] Step S4, determine whether the to-be-tested electric door is faulty according to the first detection data and the second detection data.

[0146] In the specific implementation of the embodiment, based on the state switching comparison mechanism, the detection signal difference before and after the state change of the electric door is compared to determine whether the electric door is faulty.

[0147] The normally closed contact (NC) state is detected by the first constant current source, and the normally open contact (NO) state is detected by the second constant current source, and the voltage comparator converts the contact on-off into high-low level signals.

[0148] When the electric door state is switched under normal logic, the normally closed contact and the normally open contact should present complementary states (one is closed and the other is open).

[0149] The detection signal of the comparator output in the initial state of the electric door is recorded as the first detection data. For example, when the accelerator is not pressed, the normally closed contact is closed, corresponding to a low level, and the normally open contact is open, corresponding to a high level.

[0150] The detection signal of the comparator output after the state switching of the electric door is recorded as the second detection data. For example, after the accelerator is pressed, the normally closed contact is open, corresponding to a high level, and the normally open contact is closed, corresponding to a low level.

[0151] When the fault is determined, if the change of the two detection data does not conform to the expected logic, for example, the signal does not change or changes abnormally before and after the state switching, it is determined that the electric door is faulty.

[0152] Through the comparison before and after the state switching, whether the electric door is faulty can be distinguished.

[0153] In another embodiment provided by the application, the step S4 specifically comprises:

[0154] When the two detection signals in the first detection data are inconsistent, and compared with the first detection data, the two detection signals in the second detection data are flipped, it is determined that the to-be-tested electric door is not faulty;

[0155] When the two detection signals in the first detection data are consistent, or compared with the first detection data, the two detection signals in the second detection data are not flipped, it is determined that the to-be-tested electric door is faulty.

[0156] In the embodiment, the detection method is based on logical complementarity, and whether the state signals of the normally closed (NC) and normally open (NO) contacts are mutually exclusive is compared to determine the fault.

[0157] In the normal state, the NC and NO contacts must present complementary states (i.e., one is closed and the other is open) when the accelerator is in any state.

[0158] If the closed state is defined as 0 and the open state is defined as 1, then in the normal state:

[0159] Initial state (e.g., without pressing the accelerator): NC = 0, NO = 1, the detection signal is (0, 1). Switched state (e.g., pressing the accelerator): NC = 1, NO = 0, the detection signal is (1, 0).

[0160] In the two detection data, the signals of the NC and NO contacts are always inconsistent (the exclusive or result is 1), and the signal in the second detection data is inverted.

[0161] In the fault state, if the conduction resistance of the NC or NO contact abnormally increases, then both signals will be 0 or 1. When the abnormal resistance contact is closed or increased, the detection signal of the voltage comparator corresponding to the contact is high, and no inversion occurs.

[0162] If the NC or NO contact is abnormally conducted, i.e., there is a situation where both contacts are conducted, then both signals will be 1, and the switching contact will not be inverted.

[0163] The two detection data are compared to reduce the misjudgment rate of single-point detection. Without additional sensors or complex circuits, the judgment can be completed only by comparing the output signals, thereby reducing the cost.

[0164] It should be noted that, for those skilled in the art, without departing from the principles of the present application, a number of improvements and refinements can be made, and these improvements and refinements are also considered within the scope of protection of the present application.

Claims

1. A fault detector for a throttle switch assembly, characterized in that: including at least one detection circuit; Each detection circuit includes three constant current sources with equal output currents, a first resistor, and two voltage comparators; The input terminals of the three constant current sources are all used to input reference current; The output end of the first constant current source is used to connect to the normally closed contact of the switch to be tested in the throttle switch assembly, the output end of the second constant current source is used to connect to the normally open contact of the switch to be tested, and the output end of the third constant current source is grounded through the first resistor; the common contact of the switch to be tested is grounded; Two input terminals of the first voltage comparator are connected to the output terminal of the first constant current source and the output terminal of the third constant current source respectively; Two input terminals of the second voltage comparator are connected to the output terminal of the second constant current source and the output terminal of the third constant current source respectively; the output terminals of the first voltage comparator and the second voltage comparator are used to output detection signals.

2. The fault detector of the throttle and switch assembly according to claim 1, characterized in that: Each detection circuit also includes two indicating devices; The two indicating devices output different indicator light signals according to the levels of the detection signals output by the first voltage comparator and the second voltage comparator respectively.

3. The fault detector of the throttle and switch assembly according to claim 2, characterized in that: Each indicating device includes two current limiting resistors, two indicator lights of different colors and a NOT gate; The input end of the NOT gate is used to connect to the output end of the corresponding voltage comparator; The input end of the NOT gate is connected to the input end of the first indicator light through a first current limiting resistor, the output end of the NOT gate is connected to the input end of the second indicator light through a second current limiting resistor, and the output ends of the first indicator light and the second indicator light are grounded.

4. The fault detector of the throttle and switch assembly according to claim 2, characterized in that: Each indicating device includes a current limiting resistor, a light emitting diode and a switch tube; The input end of the switch tube is used to connect to a voltage source, the control end of the switch tube is used to connect to the output end of the corresponding voltage comparator, and the output end of the switch tube is grounded through the current limiting resistor and the light emitting diode.

5. The fault detector of the throttle switch assembly according to claim 2, characterized in that: The number of the detection circuits is the same as the number of switches to be tested in the throttle switch assembly; Each detection circuit is used to detect a switch to be tested in the throttle switch assembly.

6. The fault detector of the throttle switch assembly according to claim 3, characterized in that: In each detection circuit, the output end of the first constant current source connected to the input end of the first voltage comparator and the output end of the second constant current source connected to the input end of the second voltage comparator are both in-phase input ends.

7. The fault detector of the throttle and switch assembly according to claim 3, characterized in that: Each detection circuit further includes a first contact for plugging and unplugging connection with the normally closed contact; Each detection circuit also includes a second plug for plugging and unplugging connection with the normally closed contact; Each detection circuit further includes a third plug for plugging and unplugging connection with the common contact; The first plugs, second plugs and third plugs of all detection circuits are concentrated into a plug array.

8. The fault detector of the throttle and switch assembly according to claim 3, characterized in that: The indicator lights of the indicating devices of all the detection circuits are arranged in an array.

9. A detection method for a fault detector of a throttle switch assembly, characterized in that: A fault detector for a throttle and switch assembly according to any one of claims 1 to 8 is applicable, wherein the method comprises: Connecting the output end of the first constant current source to the normally closed contact of the switch to be tested, and connecting the output end of the second constant current source to the normally open contact of the switch to be tested; Recording detection signals outputted from the output terminals of the first voltage comparator and the second voltage comparator as first detection data; Switching the normally open / normally closed state of the electric switch to be tested, and recording the detection signals outputted by the output terminals of the first voltage comparator and the second voltage comparator as second detection data; Determine whether the switch to be tested is faulty based on the first detection data and the second detection data.

10. The detection method of the throttle and switch assembly fault detector according to claim 9, characterized in that: Determining whether the switch to be tested is faulty according to the first detection data and the second detection data includes: When the two detection signals in the first detection data are inconsistent, and when the two detection signals in the second detection data are reversed compared with the first detection data, it is determined that the switch to be tested is not faulty; When the two detection signals in the first detection data are consistent, or when compared with the first detection data, the two detection signals in the second detection data are not reversed, it is determined that the switch to be tested is faulty.

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