Valve state detection system for combustible gas detector

Abstract

The invention discloses a valve state detection system for a combustible gas detector. The valve state detection system comprises an MCU, a first amplifier, a second amplifier and an LC phase-shifting frequency-selecting network circuit, the MCU is electrically connected with the first amplifier and is used for sending a detection command signal to the first amplifier and starting the first amplifier; the LC phase-shifting frequency-selecting network circuit comprises an electromagnetic valve coil, and the LC phase-shifting frequency-selecting network circuit is electrically connected between the input end and the output end of the first amplifier and used for determining the oscillation frequency of a signal sent by the first amplifier; the MCU, the first amplifier, the second amplifier, the LC phase-shift frequency-selection network circuit and the like are arranged, and the influence of the solenoid valve coil on the LC phase-shift frequency-selection network circuit is utilized, so that the situation that the solenoid valve breaks down or the state is changed can be detected in real time, risks are found, controlled and resolved in time, and the accuracy and effectiveness of safety supervision are improved.

Description

Technical Field

[0001] The invention relates to the technical field of electromagnetic valve detection, in particular to a valve state detection system for a combustible gas detector. Background Art

[0002] As clean energy such as natural gas and petroleum gas has entered thousands of households, replacing traditional highly polluting fuels such as coal, gas leak detection technology and equipment have also provided strong guarantees for the safe use of gas.

[0003] However, the existing gas leak detection products based on Internet of Things technology only have the functions of reporting to the Internet and shutting off the pipeline when a leak occurs. There is no specific detection and identification technology for solenoid valve failures and valve state changes. For this reason, we propose a valve state detection system for combustible gas detectors. Summary of the invention

[0004] The object of the present invention is to provide a valve state detection system for a combustible gas detector to solve the problems raised in the above background technology.

[0005] To achieve the above object, the present invention provides the following technical solutions: A valve state detection system for a combustible gas detector comprises an MCU, a first amplifier, a second amplifier and an LC phase-shift frequency-selective network circuit; The MCU is electrically connected to the first amplifier and is used to send a detection command signal to the first amplifier to start the first amplifier; The LC phase-shift frequency-selective network circuit includes a solenoid valve coil, and the LC phase-shift frequency-selective network circuit is electrically connected between the input end and the output end of the first amplifier, and is used to determine the oscillation frequency of the signal sent by the first amplifier; The input end of the second amplifier is connected to the output end of the first amplifier, the output end of the second amplifier is connected to the input end of the MCU, and the second amplifier is used to isolate the oscillation signal received from the first amplifier and send it to the MCU.

[0006] As a further solution of the present invention: the MCU sends a detection command signal to the first amplifier according to a preset period T.

[0007] As a further solution of the present invention: the MCU determines the state of the solenoid valve by comparing the frequencies of the two previous and subsequent oscillation signals. If the frequency of the detected oscillation signal increases and the absolute value of the difference is greater than the conversion threshold f1, it is determined that the solenoid valve is switched from the closed state to the open state; if the frequency of the detected oscillation signal decreases and the absolute value of the difference is greater than the conversion threshold f1, it is determined that the solenoid valve is switched from the open state to the closed state.

[0008] As a further solution of the present invention: the MCU determines the state of the solenoid valve by the frequency of the real-time oscillation signal. If the detected oscillation signal frequency is greater than the normal threshold f2, it is determined that the solenoid valve coil turns are short-circuited; if no oscillation signal is detected, it is determined that the solenoid valve is short-circuited or disconnected.

[0009] Compared with the prior art, the present invention has the following beneficial effects: The present invention arranges an MCU, a first amplifier, a second amplifier, and an LC phase-shift frequency-selective network circuit, etc., and utilizes the influence of the solenoid valve coil on the LC phase-shift frequency-selective network circuit, so as to detect in real time whether the solenoid valve has failed or the state has changed, thereby timely discovering, controlling, and resolving risks, thereby improving the accuracy and effectiveness of safety supervision. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 The figure is a structural block diagram of a valve status detection system for a combustible gas detector.

[0011] Among them, MCU1, first amplifier 2, second amplifier 3, LC phase shift frequency selection network circuit 4, solenoid valve coil 5. DETAILED DESCRIPTION

[0012] In order to make the technical problems, technical solutions and beneficial effects to be solved by the present invention more clearly understood, the present invention will be further described in detail below in conjunction with embodiments. It should be understood that the specific embodiments described herein are only used to explain the present invention and are not used to limit the present invention.

[0013] It should be noted that when an element is referred to as being "fixed to" or "disposed on" another element, it can be directly on the other element or indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or indirectly connected to the other element.

[0014] It should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside" and "outside" etc., indicating orientations or positional relationships, are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0015] In addition, the terms "first", "second", and "third" are used for descriptive purposes only and should not be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of the features.

[0016] See also Figure 1 In an embodiment of the present invention, a valve state detection system for a combustible gas detector includes an MCU1, a first amplifier 2, a second amplifier 3 and an LC phase-shift frequency-selective network circuit 4; the MCU1 is electrically connected to the first amplifier 2, and is used to send a detection command signal to the first amplifier 2 to start the first amplifier 2; the LC phase-shift frequency-selective network circuit 4 contains an electromagnetic valve coil 5, and the LC phase-shift frequency-selective network circuit 4 is electrically connected between the input end and the output end of the first amplifier 2, and is used to determine the oscillation frequency of the signal emitted by the first amplifier 2; the input end of the second amplifier 3 is connected to the output end of the first amplifier 2, and the output end of the second amplifier 3 is connected to the input end of the MCU1, and the second amplifier 3 is used to isolate the oscillation signal received from the first amplifier 2 and send it to the MCU1.

[0017] The present invention adopts the above scheme. Since the LC phase-shift frequency selection network circuit 4 is a circuit that uses an LC circuit (composed of an inductor and a capacitor) to achieve frequency selection and phase adjustment, it can select a specific frequency by adjusting the values ​​of the inductor and the capacitor. At the same time, due to the characteristics of its inductor and capacitor elements, it can also achieve phase adjustment, that is, phase shift function. Secondly, when the solenoid valve is in different working states, the hysteresis loss and eddy current loss of the solenoid valve coil 5 have large deviations, which will cause the inductance of the solenoid valve coil 5 to change, and then affect the oscillation frequency determined by the LC phase-shift frequency selection network circuit 4. The second amplifier 3 isolates the oscillation signal received from the first amplifier 2 and sends it to MCU1. MCU1 can judge the state of the solenoid valve by comparing the frequencies of the two oscillation signals before and after. The overall structure is simple and the operation is stable.

[0018] In one embodiment of the present invention, the MCU 1 sends a detection command signal to the first amplifier 2 according to a preset period T.

[0019] In one embodiment of the present invention, the MCU determines the state of the solenoid valve by comparing the frequencies of two previous and subsequent oscillation signals. If the frequency of the detected oscillation signal increases and the absolute value of the difference is greater than the switching threshold f1, it is determined that the solenoid valve is switched from a closed state to an open state; if the frequency of the detected oscillation signal decreases and the absolute value of the difference is greater than the switching threshold f1, it is determined that the solenoid valve is switched from an open state to a closed state.

[0020] In one embodiment of the present invention, the MMCU determines the state of the solenoid valve by the frequency of the real-time oscillation signal. If the detected oscillation signal frequency is greater than the normal threshold f2, it is determined that the solenoid valve coil is short-circuited between turns; if no oscillation signal is detected, it is determined that the solenoid valve is short-circuited or disconnected.

[0021] Specifically, during the use of the present invention, the first amplifier 2 starts to oscillate after receiving the detection signal sent by the MCU1 according to a preset period. Since the position of the internal street iron of the solenoid valve is different when the solenoid valve is in different states, the hysteresis loss and eddy current loss of the solenoid valve coil 5 are different, resulting in different inductances of the solenoid valve coil 5, thereby making the LC phase shift and frequency selection network circuit 4 determine the different frequencies of the oscillation signal output by the first amplifier 2.

[0022] The second amplifier 3 isolates the oscillation signal received from the first amplifier 2 and sends it to MCU1. MCU1 determines the state of the solenoid valve by comparing the frequencies of the two oscillation signals before and after. If the detected signal frequency rises and the absolute value of the difference is greater than the switching threshold of 1kHz, it is determined that the solenoid valve is switched from closed to open; if the detected signal frequency drops and the absolute value of the difference is greater than the switching threshold of 1kHz, it is determined that the solenoid valve is switched from open to closed; if the detected signal frequency is greater than the normal threshold of 120kHz, it is determined that the 5 turns of the solenoid valve coil are short-circuited; if no signal is detected, it is determined that the solenoid valve is short-circuited or disconnected.

[0023] Although the present invention has been described in detail with reference to the aforementioned embodiments, it is still possible for those skilled in the art to modify the technical solutions described in the aforementioned embodiments, or to make equivalent substitutions for some of the technical features therein. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the protection scope of the present invention.

Claims

1. A valve status detection system for a combustible gas detector, characterized in that: It comprises an MCU (1), a first amplifier (2), a second amplifier (3) and an LC phase-shift frequency-selective network circuit (4); The MCU (1) is electrically connected to the first amplifier (2) and is used to send a detection command signal to the first amplifier (2) to start the first amplifier (2); The LC phase-shift frequency-selective network circuit (4) includes a solenoid valve coil (5), and the LC phase-shift frequency-selective network circuit (4) is electrically connected between the input end and the output end of the first amplifier (2), and is used to determine the oscillation frequency of the signal emitted by the first amplifier (2); The input end of the second amplifier (3) is connected to the output end of the first amplifier (2), and the output end of the second amplifier (3) is connected to the input end of the MCU (1). The second amplifier (3) is used to isolate the oscillation signal received from the first amplifier (2) and send it to the MCU (1).

2. A valve state detection system for a combustible gas detector according to claim 1, characterized in that: The MCU (1) sends a detection command signal to the first amplifier (2) according to a preset period T.

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