An emergency stop solenoid valve circuit fault detection device and detection method

Abstract

The present invention discloses an emergency stop solenoid valve line fault detection device, which includes a first power supply, a second power supply, a control switch, a first diode, a first resistor, a voltage monitoring circuit and a fault alarm signal generation circuit. The first power supply is connected to one end of the control switch, and the other end of the control switch is connected to the negative electrode of the first diode and an input end of the fault alarm signal generation circuit; the second power supply is connected to one end of the first resistor, the other end of the first resistor is connected to the positive electrode of the first diode and the voltage monitoring circuit, and the voltage monitoring circuit is also connected to another input end of the fault alarm signal generation circuit. The present invention can accurately detect the line fault when the solenoid valve fails to act, without complex processors and software, and the hardware circuit is used to detect the solenoid valve line fault, and the line fault includes open circuit fault and short circuit fault, ensuring the safe and reliable operation of the solenoid valve during operation.

Description

Technical Field

[0001] The present invention relates to the technical field of line fault detection, and particularly to an emergency stop solenoid valve line fault detection device and a detection method. Background Art

[0002] On marine engines, due to high temperature, large vibration, and strong corrosion, line faults are likely to occur. Moreover, the engine space is compact, and the lines are generally arranged densely and bundled together. In most cases, even if a cable fails, it is not easy to detect. The emergency stop of a marine engine cuts off the engine fuel supply through a solenoid valve to achieve the purpose of protecting the engine. If a fault in the emergency stop solenoid valve line is not detected in time, the engine cannot be emergently stopped in an emergency, which may lead to permanent engine failure and even endanger the safety of ship operation.

[0003] The solenoid valve line fault detection generally has two functions: open circuit detection and short circuit detection. Currently, the solenoid valve line fault detection methods with open circuit and short circuit detection functions usually detect when the solenoid valve coil is energized, and the processor judges whether the solenoid valve line fails through software. The detection device and method are complex.

[0004] However, the emergency stop of a marine engine is a device that quickly stops the engine in an emergency. Generally, the emergency stop is only used in an emergency. If the detection is carried out when it is powered on and working, once a line fault occurs, even if an alarm is issued, it is difficult to avoid the problem that the engine cannot be emergently stopped. Obviously, the method of detecting the line fault by energizing the solenoid valve coil is not suitable for the emergency stop solenoid valve of a marine engine. In addition, most of the emergency stop devices in the marine engine control system are controlled by hard-wired switches, and it is not suitable for complex software logic judgment and analysis by a processor.

[0005] Therefore, those skilled in the art are committed to developing a brand-new emergency stop solenoid valve line fault detection device that replaces the processor for detection and a detection method using this device. Summary of the Invention

[0006] In view of the above-mentioned defects of the prior art, the technical problem to be solved by the present invention is to provide a brand-new emergency stop solenoid valve line fault detection device that replaces the processor for detection.

[0007] To achieve the above object, the present invention provides an emergency stop solenoid valve line fault detection device, including a first power supply, a second power supply, a control switch, a first diode, a first resistor, a voltage monitoring circuit, and a fault alarm signal generation circuit. The first power supply is connected to one end of the control switch, and the other end of the control switch is connected to the negative electrode of the first diode and an input terminal of the fault alarm signal generation circuit. The second power supply is connected to one end of the first resistor, and the other end of the first resistor is connected to the positive electrode of the first diode and the voltage monitoring circuit. The voltage monitoring circuit is also connected to another input terminal of the fault alarm signal generation circuit.

[0008] The control switch is one of a relay, a mechanical button, a metal-oxide-semiconductor field-effect transistor, and a bipolar transistor.

[0009] The first diode can be a single diode or multiple diodes connected in series.

[0010] The voltage monitoring circuit includes a first comparator, a second comparator, a second diode, a third diode, a second resistor, and a third resistor.

[0011] The second power supply is connected to one end of the second resistor and one end of the third resistor. The positive electrode of the second diode, the other end of the second resistor are connected to the output terminal of the first comparator.

[0012] The negative electrode of the first comparator and the positive electrode of the second comparator are connected and then connected to the other end of the first resistor and the positive electrode of the first diode.

[0013] The positive electrode of the third diode, one end of the third resistor are connected to the output terminal of the second comparator.

[0014] The negative electrode of the second diode and the negative electrode of the third diode are connected and then connected to another input terminal of the fault alarm signal generation circuit.

[0015] The fault alarm signal generation circuit includes an AND gate, an RC filter circuit, a fourth resistor, a fifth resistor, and an optocoupler.

[0016] One end of the fourth resistor is connected to the positive electrode of the light-emitting diode in the optocoupler, and the other end is connected to the negative electrode of the first diode. The negative electrode of the light-emitting diode in the optocoupler is connected to the ground terminal.

[0017] One end of the fifth resistor is connected to the second power supply, and the other end is connected to the collector of the light-receiving transistor in the optocoupler and the AND gate. The emitter of the light-receiving transistor in the optocoupler is connected to the ground terminal.

[0018] The voltage monitoring circuit is connected to one input terminal of the AND gate, and the output terminal of the AND gate is connected to the input terminal of the RC filtering circuit.

[0019] The negative electrode of the second diode is connected to the negative electrode of the third diode and then connected to the other input terminal of the AND gate.

[0020] The present invention also provides a detection method using the above-mentioned emergency stop solenoid valve line fault detection device for detection, including a solenoid valve coil. One end of the solenoid valve coil is connected to the ground terminal through a second line, and the other end of the solenoid valve coil is connected to the other end of the control switch, the negative electrode of the first diode, and an input terminal of the fault alarm signal generation circuit through a first line.

[0021] The beneficial effects of the present invention are as follows: The emergency stop solenoid valve line fault detection device of the present invention includes a first power supply, a second power supply, a control switch, a first diode, a first resistor, a voltage monitoring circuit, and a fault alarm signal generation circuit. The first power supply is connected to one end of the control switch, and the other end of the control switch is connected to the negative electrode of the first diode and an input terminal of the fault alarm signal generation circuit; the second power supply is connected to one end of the first resistor, the other end of the first resistor is connected to the positive electrode of the first diode and the voltage monitoring circuit, and the voltage monitoring circuit is also connected to the other input terminal of the fault alarm signal generation circuit; when using this circuit to detect the solenoid valve line, the solenoid valve coil line is connected to the other end of the control switch, the negative electrode of the first diode, and an input terminal of the fault alarm signal generation circuit. The present invention can accurately detect the line fault when the solenoid valve does not act, without complex processors and software, and uses a hardware circuit to detect the solenoid valve line fault, which includes open circuit faults and short circuit faults, ensuring the safe and reliable operation of the solenoid valve during work. Description of the Drawings

[0022] Figure 1 is a schematic structural principle diagram of the present invention;

[0023] Figure 2 is a schematic circuit principle diagram of an implementation manner of the voltage monitoring circuit of the present invention;

[0024] Figure 3 is a schematic circuit principle diagram of an implementation manner of the fault alarm signal generation circuit of the present invention;

[0025] Figure 4 is a waveform output diagram of the voltage monitoring circuit;

[0026] Figure 5 is a waveform output diagram of the fault alarm signal generation circuit. Detailed Embodiments

[0027] The present invention will be further described below in conjunction with the accompanying drawings and embodiments. It should be noted that in the description of the present invention, the orientation or positional relationship indicated by the terms "upper", "lower", "left", "right", "inner", "outer", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific manner, and thus should not be construed as a limitation of the present invention. The terms "first", "second", "third", etc. are only used for descriptive purposes and cannot be construed as indicating or implying relative importance.

[0028] The following describes the embodiments of the present invention in detail. The following embodiments mainly illustrate a fault detection device for a marine emergency stop circuit, but the circuit fault detection device involved in this embodiment can also be applied to other marine solenoid valves and devices for detecting various circuit faults outside ships.

[0029] As Figures 1 to 3 shown, a fault detection device for an emergency stop solenoid valve circuit includes a first power supply V1, a second power supply V2, a control switch K1, a first diode D1, a first resistor R1, a voltage monitoring circuit 1, and a fault alarm signal generation circuit 2. One end of the first power supply V1 is connected to one end of the control switch K1, and the other end of the control switch K1 is connected to the negative electrode of the first diode D1 and an input terminal of the fault alarm signal generation circuit 2; the second power supply V2 is connected to one end of the first resistor R1, and the other end of the first resistor R1 is connected to the positive electrode of the first diode D1 and the voltage monitoring circuit 1, and the voltage monitoring circuit 1 is also connected to the other input terminal of the fault alarm signal generation circuit 2; the present invention can accurately detect the circuit fault when the solenoid valve does not act, without complex processors and software, and the circuit fault of the solenoid valve is detected by a hardware circuit. This circuit fault includes open circuit faults and short circuit faults, ensuring the safe and reliable operation of the solenoid valve during operation.

[0030] In this embodiment, a detection method using the above-mentioned fault detection device for an emergency stop solenoid valve circuit includes a solenoid valve coil L. One end of the solenoid valve coil L is connected to the ground terminal GND through a second line X2, and the other end of the solenoid valve coil is connected to the other end of the control switch K1, the negative electrode of the first diode D1, and an input terminal of the fault alarm signal generation circuit 2 through a first line X1. Then, the fault detection device for the emergency stop solenoid valve circuit is powered on to perform detection. At this time, the fault detection is performed when the solenoid valve is not working.

[0031] In this embodiment, the control switch K1 is one of a relay, a mechanical button, a metal-oxide-semiconductor field-effect transistor (MOSFET), and a bipolar junction transistor (BJT); the first diode D1 can be a single diode or multiple diodes connected in series.

[0032] Among them, the voltage monitoring circuit 1 has multiple implementation manners. A preferred one is that the voltage monitoring circuit 1 includes a first comparator U1, a second comparator U2, a second diode D11, a third diode D12, a second resistor R11, and a third resistor R12; the second power supply V2 is connected to one end of the second resistor R11 and one end of the third resistor R12, and the positive electrode of the second diode D11, the other end of the second resistor R11 are connected to the output terminal of the first comparator U1; the negative electrode of the first comparator U1 and the positive electrode of the second comparator U2 are connected and then connected to the other end of the first resistor R1 and the positive electrode of the first diode D1; the positive electrode of the third diode D12, one end of the third resistor R12 are connected to the output terminal of the second comparator U2; the negative electrode of the second diode D11 and the negative electrode of the third diode D12 are connected and then connected to the fault alarm signal generation circuit 2.

[0033] Among them, the fault alarm signal generation circuit 2 has multiple implementation manners. A preferred one is that the fault alarm signal generation circuit 2 includes an AND gate 21, an RC filter circuit 22, a fourth resistor R14, a fifth resistor R15, and an optocoupler U3; one end of the fourth resistor R14 is connected to the positive electrode of the light-emitting diode in the optocoupler U3, and the other end is connected to the negative electrode of the first diode D1. The negative electrode of the light-emitting diode in the optocoupler U3 is connected to the ground terminal GND; one end of the fifth resistor R15 is connected to the second power supply V2, and the other end is connected to the collector of the light-receiving triode in the optocoupler U3 and the AND gate 21. The emitter of the light-receiving triode in the optocoupler U3 is connected to the ground terminal GND; the voltage monitoring circuit 1 is connected to one input terminal of the AND gate 21, and the output terminal of the AND gate 21 is connected to the input terminal of the RC filter circuit 22; the negative electrode of the second diode D11 and the negative electrode of the third diode D12 are connected and then connected to the other input terminal of the AND gate 21.

[0034] The second power supply V2 provides a detection excitation voltage when the solenoid valve is not energized. The voltage of the second power supply V2 is less than or equal to the voltage of the first power supply V1; the control switch K1 is a high-side switch, and the control switch K1 controls whether the solenoid valve coil L is connected to the first power supply V1; the first diode D1, when the control switch K1 is closed, isolates the first power supply V1 controlled by it and the voltage monitoring circuit 1.

[0035] Generally, the resistance RL of the solenoid valve coil L is in the range of dozens of ohms to hundreds of ohms. The value of the first resistor R1 should be dozens of times that of the resistance RL of the solenoid valve coil L. After the second power supply V2 is limited by the first resistor R1, it is not sufficient to drive the solenoid valve to work.

[0036] The voltage monitoring circuit 1 monitors the first signal S1 generated at the connection node between the positive electrode of the first diode D1 and the first resistor R1, and detects the conditions of the first line X1 and the second line X2 according to the first signal S1. When the control switch K1 is disconnected, the conditions of the first line X1 and the second line X2 are divided into a short - circuit condition, a normal condition, and an open - circuit condition.

[0037] Short - circuit condition: When the control switch K1 is disconnected and the first line X1 and the second line X2 are short - circuited, the voltage of the second power supply V2 flows back to the ground terminal GND through the first resistor R1 and the first diode D1, and the voltage of the first signal S1 is equal to VF, where VF is the voltage drop of the first diode D1.

[0038] Normal condition: When the control switch K1 is disconnected and the first line X1 and the second line X2 are normally connected, the voltage of the second power supply V2 flows back to the ground terminal GND through the first resistor R1, the first diode D1, and the solenoid valve coil L. The voltage of the first signal S1 is equal to the voltage drop of the first diode D1 plus the voltage drop of the solenoid valve coil L, that is, the voltage drop of the solenoid valve coil is equal to (V2 - VF)×RL / (R + RL), and the first signal S1 = VF+(V2 - VF)×RL / (R + RL).

[0039] Open - circuit condition: When the control switch K1 is disconnected and the first line X1 and the second line X2 are open - circuited, the voltage of the first signal S1 is equal to the voltage of the second power supply V2.

[0040] When the control switch K1 is closed, since the voltage of the second power supply V2 is less than the voltage of the first power supply V1, no current flows through the first diode D1, and the voltage of the first signal S1 is equal to the voltage of the second power supply V2.

[0041] In the voltage monitoring circuit 1, reference voltages VL and VH are predefined. The reference voltage VL should be greater than the input voltage in the short - circuit condition, that is, greater than VF; the reference voltage VH should be greater than the voltage in the normal line condition, that is, greater than VF+(V2 - VF)×RL / (R + RL), and should not exceed the voltage of the power supply V2 at the same time.

[0042] The voltage of the first signal S1 of the voltage monitoring circuit 1 is compared with the predefined reference voltages VL and VH to generate a second signal S2.

[0043] The voltage monitoring circuit 1 monitors the voltage of the first signal S1 in real time and generates a second signal S2, which can distinguish normal line conditions, fault conditions, and control switch on conditions.

[0044] Its comparison principle is as follows:

[0045] When the voltage monitoring circuit is powered on, when the first signal S1 = VF (when the first line X1 and the second line X2 are short-circuited), the output signal Su1 of the first comparator U1 is high level, the output signal Su2 of the second comparator U2 is low level, and the second signal S2 outputs high level.

[0046] When the voltage of the first signal S1 is equal to VF+(V2 - VF)×RL / (R + RL) (when the first line X1 and the second line X2 are normal), since it is preset that VL < S1 < VH, the output signal Su1 of the first comparator U1 is low level, the output signal Su2 of the second comparator U2 is low level, and the second signal S2 outputs low level.

[0047] When the voltage of the first signal S1 is equal to the voltage V2 (when the first line X1 and the second line X2 are open-circuited or the control switch K1 is closed), the output Su1 of the first comparator U1 is low level, the output signal Su2 of the second comparator U2 is high level, and the second signal S2 outputs high level.

[0048] Figure 4 It is the waveform output diagram of the voltage monitoring circuit 1, further illustrating the function of the voltage monitoring circuit. From 0 to t2, it is the case of line open-circuit (or control switch K1 is turned on); from t2 to t3, it is the waveform when the line is normal; from t3 to t4, it is the waveform when the line is short-circuited.

[0049] When the control switch K1 is closed, the first signal S1 is consistent with the input signal of the open-circuited first line X1 and second line X2. Therefore, the fault alarm signal generation circuit 2 introduces a first control switch signal Scs.

[0050] When the control switch K1 is closed, that is, when the solenoid valve coil L is powered on and working, the fault alarm signal generation circuit 2 shields the fault alarm signal to avoid false alarms.

[0051] The fault alarm signal generation circuit 2 generates a fault alarm signal Vout according to the first signal S1 and the second signal S2.

[0052] The first control signal Scs is converted into a second control signal through the optocoupler U3

[0053] When the control switch K1 is turned on, the first control signal Scs is at a high level, the light-emitting diode in the optocoupler U3 conducts, emits light, and the light-receiving triode in the optocoupler U3 conducts. The second control signal is connected to the ground terminal GND through the light-receiving triode and outputs a low level.

[0054] When the control switch K1 is turned off, the first control signal Scs is about one-tenth of the voltage of the second power supply V2 and can be considered as a low level. The light-emitting diode in the optocoupler U3 is cut off, and the light-receiving triode in the optocoupler U3 is cut off. The second control signal is connected to the second power supply V2 through the fifth resistor R15 and outputs a high level.

[0055] The AND gate 21 receives the second control signal and the second signal S2 for logical calculation to generate the third signal S3.

[0056] The RC filter circuit 22 is used to suppress interference signals and narrow pulse interference caused by the gentle rising edge of the comparator.

[0057] Since the line fault signal is a low-speed signal, the RC time constant of the RC filter circuit 22 should be slightly larger to avoid false alarms due to interference.

[0058] Figure 5 For the waveform output diagram of the fault alarm signal generation circuit 2, the function of the fault alarm signal generation circuit 2 is further illustrated.

[0059] From time 0 to t1, it is the waveform when the first control switch K1 is turned on. In this case, the shielding alarm occurs to avoid false alarms; from time t1 to t2, it is the waveform when the first line X1 and the second line X2 are disconnected; from time t2 to t3, it is the waveform when the first line X1 and the second line X2 are normal; from time t3 to t4, it is the waveform when the first line X1 and the second line X2 are short-circuited.

[0060] The fault alarm signal generation circuit 2 generates a fault alarm signal Vout. When the first line X1 and the second line X2 are normal or the solenoid valve is powered on and working, this signal is at a low level. When the first line X1 and the second line X2 have a line fault, this signal is at a high level.

[0061] The fault alarm signal Vout can be connected to a controller to display the alarm status on the control system, or it can be connected to an alarm drive unit to give an audible and visual alarm.

[0062] The preferred specific embodiments of the present invention have been described in detail above. It should be understood that those of ordinary skill in the art can make many modifications and variations based on the concept of the present invention without creative efforts. Therefore, all technical solutions that can be obtained by those skilled in the art in the technical field according to the concept of the present invention through logical analysis, reasoning, or limited experiments on the basis of the prior art should fall within the protection scope determined by the claims.

Claims

1. An emergency stop solenoid valve circuit fault detection device, characterized in that: It includes a first power supply (V1), a second power supply (V2), a control switch (K1), a first diode (D1), a first resistor (R1), a voltage monitoring circuit (1), and a fault alarm signal generating circuit (2). One end of the first power supply (V1) is connected to one end of the control switch (K1), and the other end of the control switch (K1) is connected to the negative electrode of the first diode (D1) and an input terminal of the fault alarm signal generating circuit (2). One end of the second power supply (V2) is connected to one end of the first resistor (R1), and the other end of the first resistor (R1) is connected to the positive electrode of the first diode (D1) and the voltage monitoring circuit (1), and the voltage monitoring circuit (1) is also connected to another input terminal of the fault alarm signal generating circuit (2). It further includes a solenoid valve coil (L). One end of the solenoid valve coil (L) is connected to the ground terminal (GND) through a second line (X2), and the other end of the solenoid valve coil (L) is connected to the other end of the control switch (K1), the negative electrode of the first diode (D1), and an input terminal of the fault alarm signal generating circuit (2) through a first line (X1). The value of the first resistor (R1) should be dozens of times the resistance RL of the solenoid valve coil (L), and the second power supply (V2) is not sufficient to drive the solenoid valve to work after being current-limited by the first resistor (R1).

2. The emergency stop solenoid valve circuit fault detection device according to claim 1, wherein: The control switch (K1) is one of a relay, a mechanical button, a metal-oxide-semiconductor field-effect transistor, and a bipolar transistor.

3. The emergency stop solenoid valve circuit fault detection device according to claim 1, characterized in that: The first diode (D1) is a single diode or multiple diodes connected in series.

4. The emergency stop solenoid valve circuit fault detection device according to claim 1, characterized in that: The voltage monitoring circuit (1) includes a first comparator (U1), a second comparator (U2), a second diode (D11), a third diode (D12), a second resistor (R11), and a third resistor (R12). The second power supply (V2) is connected to one end of the second resistor (R11) and one end of the third resistor (R12), and the positive electrode of the second diode (D11), the other end of the second resistor (R11) are connected to the output terminal of the first comparator (U1). The negative electrode of the first comparator (U1) and the positive electrode of the second comparator (U2) are connected and then connected to the other end of the first resistor (R1) and the positive electrode of the first diode (D1). The positive electrode of the third diode (D12), one end of the third resistor (R12) are connected to the output terminal of the second comparator (U2). The negative electrode of the second diode (D11) and the negative electrode of the third diode (D12) are connected and then connected to another input terminal of the fault alarm signal generating circuit (2).

5. The emergency stop solenoid valve circuit fault detection device according to claim 4, characterized in that: The fault alarm signal generating circuit (2) includes an AND gate (21), an RC filtering circuit (22), a fourth resistor (R14), a fifth resistor (R15), and an optocoupler (U3). One end of the fourth resistor (R14) is connected to the positive electrode of the light-emitting diode in the optocoupler (U3), and the other end is connected to the negative electrode of the first diode (D1). The negative electrode of the light-emitting diode in the optocoupler (U3) is connected to the ground terminal (GND); One end of the fifth resistor (R15) is connected to the second power supply (V2), and the other end is connected to the collector of the light-receiving triode in the optocoupler (U3) and the AND gate (21). The emitter of the light-receiving triode in the optocoupler (U3) is connected to the ground terminal (GND); The voltage monitoring circuit (1) is connected to one input terminal of the AND gate (21), and the output terminal of the AND gate (21) is connected to the input terminal of the RC filtering circuit (22); The negative electrodes of the second diode (D11) and the third diode (D12) are connected and then connected to the other input terminal of the AND gate (21).

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