Gas detection device

Abstract

The utility model provides a gas detection device which mainly comprises a PWM (Pulse Width Modulation) speed regulation module, a vacuum self-priming pump, a gas chamber, a detection chamber comprising different gas sensors and signal conditioning circuits, a main control board, a stepping motor driving module, a stepping motor, an incremental encoder and the like which are fixed in a shell of the device, the parts can be physically and logically connected by adopting wires or communication protocols, the gas chamber can be respectively communicated with different detection chambers, gas to be detected can enter the different detection chambers through the gas chamber after the gas chamber is communicated, and the concentration of the gas is detected by utilizing different gas sensors and signal conditioning circuits; and a detection result is uploaded to the distributed control system, and alarm and real-time display are carried out through the sound-light alarm module and the display module. The real-time detection of different combustible and toxic gases is realized, the expansibility and universality of the gas detection device are greatly improved, the inventory occupation of power plant spare parts is reduced, and the economic benefit is improved.

Description

Technical Field

[0001] The utility model relates to the technical field of gas detection, in particular to a gas detection device. Background Art

[0002] Spare parts material management is an important part of power plant operation and maintenance. Strengthening spare parts management and enhancing the versatility of spare parts can provide guarantees for normal production and reduce inventory, and can also effectively control the capital cost of power plants. Equipment maintenance costs can be roughly divided into labor costs and spare parts costs. Spare parts consumption accounts for about 60% of equipment maintenance costs. Reducing spare parts costs is an important research topic for power plants to strengthen management, reduce costs, and increase economic benefits.

[0003] Currently, gas detectors on the market can only detect single flammable and toxic gases, while power plants need to detect the carbon monoxide concentration in the power plant area, as well as the hydrogen concentration in the battery room and the ammonia concentration in the dosing room. Therefore, in order to reduce the inventory of spare parts in power plants and to improve the scalability and versatility of the equipment, it is necessary to study a device that can detect multiple gases. Utility Model Content

[0004] The purpose of the utility model is to provide a gas detection device to solve the problem that the power plant has many types of spare parts for flammable and toxic gas detection devices, large inventory and low versatility. The specific technical solution is as follows:

[0005] A gas detection device comprises a gas chamber, a plurality of gas sensors, a plurality of signal conditioning circuits, a plurality of detection chambers, and a main control board. The output ends of the gas sensors are respectively connected to the input ends of the signal conditioning circuits. The connected gas sensors and the signal conditioning circuits are located in different detection chambers. The detection chambers have an air inlet and an air outlet. The air chambers have an air inlet and an air outlet. The air outlets of the air chambers can be respectively connected to the air inlets of each detection chamber. The output ends of the signal conditioning circuits are connected to the main control board.

[0006] Furthermore, a check valve is provided at the air inlet of the air chamber, a vacuum self-priming pump is provided in the air chamber, and the device further comprises a PWM speed regulation module connected to the vacuum self-priming pump.

[0007] Furthermore, the device also includes a key selection module, an audible and visual alarm module, a display module, a communication module, and a current output circuit connected to the main control board.

[0008] Furthermore, the device also includes a stepper motor drive module connected to the main control board, a stepper motor connected to the output end of the stepper motor drive module, and an incremental encoder connected to the output end of the stepper motor.

[0009] Furthermore, the device also includes a power supply module and a power supply voltage stabilizing module, the power supply module is connected to the vacuum self-priming pump, the gas sensor and the stepper motor, the input end of the power supply voltage stabilizing module is connected to the power supply module, and the output end is connected to the signal conditioning circuit and the main control board.

[0010] Furthermore, the device also includes a shell and a disc located inside the shell, and the multiple detection chambers, the main control board, the PWM speed regulation module, the button selection module, the sound and light alarm module, the display module, the communication module, the current output circuit, the stepper motor drive module, the stepper motor, and the incremental encoder are all configured and installed on a side of the disc away from the bottom plate of the shell, the multiple detection chambers are arranged adjacent to each other, and the cross-section of the detection chamber parallel to the disc is fan-shaped.

[0011] Furthermore, the air chamber is installed between one of the detection chambers and a side wall of the housing, and the air chamber can be connected to the detection chamber.

[0012] Furthermore, the center of the disk is connected to the center of the bottom plate of the shell through a vertical circular tube, the end of the vertical circular tube close to the bottom plate is fixedly connected to the bottom plate, the end of the vertical circular tube close to the bottom plate is an open end, the end of the vertical circular tube away from the bottom plate is spirally connected to the disk, the end of the vertical circular tube away from the bottom plate is a closed end, the side of the closed end is in contact with the detection chamber, and the side of the closed end has an air outlet at a position corresponding to the air chamber.

[0013] Further, the gas sensor includes at least one of a CO sensor, a H2 sensor and a NH3 sensor.

[0014] Furthermore, the CO sensor is an ME3 type electrochemical sensor, the H2 sensor is a TGS821 hydrogen sensor, and the NH3 sensor is an LGD F200 A type ammonia sensor.

[0015] The utility model provides a gas detection device, which has the following beneficial effects:

[0016] The utility model provides a gas detection device that can not only detect the carbon monoxide concentration in the power plant area, but also detect the concentration of hydrogen in the battery room and ammonia in the dosing room, thereby realizing real-time detection of different combustible and toxic gases, greatly improving the expansibility and versatility of the gas detection device, reducing the inventory occupancy of spare parts in the power plant, and replacing equipment in a short time when problems occur, thereby improving the utilization rate and turnover rate of accident spare parts, thereby achieving increased production and reduced consumption in the power plant and improving economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 It is a structural schematic diagram of a gas detection device provided by the utility model;

[0018] Figure 2 It is a partial structural diagram of a gas detection device in an embodiment of the utility model;

[0019] Figure 3 It is a partial structural diagram of the gas detection device in the embodiment of the utility model. DETAILED DESCRIPTION

[0020] The following will be combined with the accompanying drawings provided by the utility model to clearly and completely describe the technical solutions in the embodiments of the utility model. According to the following description, the advantages and features of the utility model will be clearer. It should be noted that the drawings are all in a very simplified form and are not in precise proportions, which are only used to conveniently and clearly assist in explaining the purpose of the embodiments of the utility model.

[0021] In the description of the present invention, unless otherwise clearly specified and limited, the terms "connection" and "connected" should be interpreted in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integrated connection; it can be a mechanical connection or an electrical connection; it can be a direct connection or an indirect connection through an intermediate medium, it can be the internal connection of two elements or the interaction relationship between two elements. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0022] In the description of the present invention, terms such as "upper", "lower", "left", "right", "front", "back", "center", "horizontal", "vertical", "top", "bottom", "inside" and "outside" and other orientations or positional relationships are based on the orientations or positional relationships shown in the accompanying drawings and are only for the convenience of description and simplification of operation, and do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0023] Embodiment: This embodiment provides a gas detection device, see Figure 1As shown, it is the internal connection diagram of the device, which mainly includes a gas chamber 1, multiple gas sensors 2, multiple signal conditioning circuits 3, a main control board 4, and multiple detection chambers 5. The multiple gas sensors 2 include a CO sensor 21, an H2 sensor 22, and an NH3 sensor 23. The output ends of the CO sensor 21, the H2 sensor 22, and the NH3 sensor 23 are respectively connected to the input ends of the corresponding signal conditioning circuits 3, and the connected gas sensors 2 and the signal conditioning circuits 3 are arranged in different detection chambers 5. The detection chambers 5 are provided with an air inlet and an exhaust port, and the gas chamber 1 is provided with an air inlet and an air outlet. The air outlet of the gas chamber 1 can be connected to the air inlet of each detection chamber 5 respectively, and the output end of the signal conditioning circuit 3 is connected to the main control board 4.

[0024] Optionally, a check valve 11 is provided at the air inlet of the air chamber 1 of the device to prevent the air in the air chamber from flowing back. A vacuum self-priming pump 12 is provided in the air chamber 1 to provide the device with a stable air source that meets the requirements of the gas sensor 2. The device is also provided with a PWM speed control module 13 connected to the vacuum self-priming pump 12 to control the rate at which the vacuum self-priming pump 12 absorbs air.

[0025] Optionally, the device is further provided with a key selection module 41, an audible and visual alarm module 42, a display module 43, a communication module 44, and a current output circuit 45 connected to the main control board 4, wherein the key selection module 41 is used as an external key input module of the main control board 4 for performing interface selection, directory selection and detection mode selection, setting alarm values ​​and system parameters, etc., such as mode 1 for H2 concentration detection; mode 2 for CO concentration detection; mode NH3 for hydrogen concentration detection; the audible and visual alarm module 42 is used to perform audible and visual alarms under the control of the main control board 4 when the gas concentration exceeds the set alarm value, so as to promptly remind the power plant operators to be vigilant and pay attention to avoid accidents; the display module 43 is used to display the concentration detection results and detection time of the detected gas in real time when the device is detecting; in order to prevent the situation where the signal output cannot be performed normally when a single signal output mode encounters a fault, a combination of the output of the communication module 44 and the output of the current output circuit 45 is adopted to ensure that the concentration detection value of each gas sensor 2 is transmitted to the DCS system in real time;

[0026] Optionally, the device is also provided with a stepper motor drive module 46 connected to the main control board 4, and the output end of the stepper motor drive module 46 is also connected to the stepper motor 47 and the incremental encoder 48 in sequence. The main control board 4 controls the stepper motor drive module 46 to drive the stepper motor 47 to select the corresponding detection chamber, and the incremental encoder 48 feeds back the recorded value to the main control board 4, and the main control board 4 displays the type of gas currently detected.

[0027] Optionally, the device is also provided with a power supply module 6 and a power supply voltage regulator module 7. The power supply module 6 can be directly connected to the vacuum self-priming pump 12, the CO sensor 21, the H2 sensor 22, the NH3 sensor 23 and the stepper motor 47 to provide a 24VDC direct current voltage for the above-mentioned components; the input end of the voltage regulator module 7 is connected to the power supply module 6, and the output end is connected to the signal conditioning circuit 3 and the main control board 4. The power supply voltage regulator module 7 is used to convert the 24VDC direct current voltage into a +5VDC direct current voltage to provide voltage to the signal conditioning module 3 and the main control board 4.

[0028] Optionally, the CO sensor 21 is an ME3 type electrochemical sensor, the H2 sensor 22 is a TGS821 hydrogen sensor, and the NH3 sensor 23 is an LGD F200 A type ammonia sensor.

[0029] Optionally, the main control board 4 is a low-power MSP430F5438 single-chip microcomputer that integrates a variety of on-chip and off-chip modules.

[0030] The working principle of the device is: select the detection mode through the key selection module 41. After the detection mode is selected, the main control board 4 controls the stepper motor drive module 46 to drive the stepper motor 47 to work. The stepper motor 47 can connect the corresponding detection chamber 5 with the air chamber 1. At the same time, the incremental encoder 48 feeds back the recorded value to the main control board 4. The main control board 4 controls the display module to display the gas type to be detected in the current detection chamber. After confirmation, adjust the PWM speed regulation module 13 to control the vacuum self-priming pump 12 to work. The vacuum self-priming pump 12 sucks the air in the space where the device is located into the air chamber 1. After sucking in enough gas source, the check valve 11 is closed, and the air to be detected enters the detection chamber 5 from the air chamber 1. The gas sensor in the detection chamber 5 contacts the air to be detected and removes the gas in the air. The composition, concentration and other information are converted into a signal that can be received by the signal conditioning circuit 3. The amplifier circuit and A / D conversion circuit in the signal conditioning circuit 3 realize signal amplification, filtering and isolation. After the processing is completed, the signal is input into the sampling channel of the main control board 4 for signal sampling. Finally, the concentration detection result is transmitted to the DCS system in real time through the communication module 44 or the current output module 45. The gas in the detection chamber 5 is discharged from the exhaust port of the detection chamber 5. At the same time, the concentration detection result and detection time of the measured gas are displayed in real time through the display module 43. If the gas concentration exceeds the set alarm value during the detection process, the sound and light alarm module 42 will sound and light alarm under the control of the main control board 4 to remind the power plant operators to be vigilant and pay attention to avoid accidents.

[0031] See also Figure 2 , 3 As shown, it is a physical installation diagram of the device. The outer shell of the device is cylindrical, and the upper surface is the front panel 8 of the device. Figure 2As shown, the front panel is provided with an on / off button 81, a mode selection button 82, a display screen 83, an indicator light 84 and a sound 85 for sound and light alarm, a PWM speed control knob 86, etc.

[0032] The lower surface is the bottom plate 10 of the device. Inside the device, there is a disk 9 with a diameter smaller than that of the cylinder connected to the bottom plate. Figure 3 As shown, a circular hole is provided at the center of the disc 9, and the disc 9 is sleeved on a vertical circular tube with one end closed through the circular hole, and is spirally connected to the outer side of the closed end of the vertical circular tube. The open end of the vertical circular tube is fixedly connected to the bottom plate 10 of the device, and a circular hole is also provided at the corresponding position of the bottom plate 10. The disc 9 can rotate at a certain angle relative to the bottom plate; with the diameter of the disc 9 as the boundary, three adjacent sector-shaped detection chambers 5 are provided on one side of the diameter, and corresponding gas sensors 2 and signal conditioning circuits 3 are respectively installed in the detection chambers 5, an air inlet is provided at the center of the outer arc surface of the detection chamber 5, and a Exhaust port; an arc-shaped air chamber 1 is arranged between one of the detection chambers 5 and the side wall of the device, and the width of the arc-shaped air chamber 1 along the diameter direction of the device is just equal to the radius of the device minus the radius of the disc, a check valve 11 is installed at the air inlet of the arc-shaped air chamber 1, a vacuum self-priming pump 12 is installed inside the arc-shaped air chamber 1, and an exhaust hole is opened at a position corresponding to the air outlet of the arc-shaped air chamber 1 on the side of the closed end of the numerical circular tube. When the disc 9 rotates, each detection chamber 5 can be in close contact with the arc-shaped air chamber 1 respectively. When each detection chamber 5 is in contact with the arc-shaped air chamber 1, the air inlet of the detection chamber 5 and the outlet of the arc-shaped air chamber 1 are in close contact with each other. The air port is just connected, and the air outlet of the detection chamber 5 is just connected to the exhaust hole of the vertical circular tube; the detection mode when the detection chamber 5 in the middle is in contact with the arc-shaped air chamber 1 is set to detection mode 1. At this time, the position of the disk is set as the rotation origin. The disk 9 is rotated 60° clockwise from the rotation origin. At this time, the detection chamber 5 on the left side of the middle detection chamber is in contact with the arc-shaped air chamber 1, which can be set to detection mode 2. The disk 9 is rotated 60° counterclockwise from the rotation origin. At this time, the detection chamber 5 on the right side of the middle detection chamber is in contact with the arc-shaped air chamber 1, which can be set to detection mode 3. If the gas sensor in the middle detection chamber is H 2 sensor, then detection mode 1 is the detection of H2 concentration; if the gas sensor in the left detection chamber is a CO sensor, then detection mode 2 is the detection of CO concentration; if the gas sensor in the right detection chamber is an NH3 sensor, then detection mode 3 is the detection of NH3 concentration; on the other side of the diameter of the disk 9 are distributedly installed a PWM speed regulation module 13, a main control board 4, a button selection module 41, an audible and visual alarm module 42, a display module 43, a communication module 44, a current output circuit 45, a stepper motor drive module 46, a stepper motor 47, an incremental encoder 48, a power supply module 5 and a power supply voltage stabilization module 6.

[0033] After the detection mode selection is completed, the stepper motor 47 drives the disk to rotate. If detection mode 1 is selected, the disk 9 is at the position of the rotation origin. If detection mode 2 is selected, the stepper motor 47 drives the disk 9 to rotate 60° clockwise from the position of the rotation origin. If detection mode 3 is selected, the stepper motor 47 drives the disk 9 to rotate 60° counterclockwise from the position of the rotation origin. At this time, the incremental encoder 48 uses the number of pulses to record the rotation angle of the disk, and returns the recorded value to the main control board 4. The main control board 4 displays the gas type detected by the current detection chamber through the display module 43. After confirming that it is correct with the selected detection mode, the check valve 11 is opened to carry out the subsequent detection process.

[0034] Those skilled in the art should understand that the present invention can be implemented in many other specific forms without departing from the spirit and scope of the present invention, and all other embodiments obtained by those of ordinary skill in the art based on the embodiments of the present invention without making any creative efforts shall fall within the scope of protection of the present invention.

Claims

1. A gas detection device, characterized in that: The device includes an air chamber, multiple gas sensors, multiple signal conditioning circuits, multiple detection chambers, and a main control board. The output ends of the gas sensors are respectively connected to the input ends of the signal conditioning circuits. The connected gas sensors and the signal conditioning circuits are located in different detection chambers. The detection chambers have an air inlet and an air outlet. The air chambers have an air inlet and an air outlet. The air outlets of the air chambers can be respectively connected to the air inlets of each detection chamber. The output ends of the signal conditioning circuits are connected to the main control board.

2. The gas detection device according to claim 1, characterized in that: A check valve is arranged at the air inlet of the air chamber, a vacuum self-priming pump is arranged in the air chamber, and the device further comprises a PWM speed regulating module connected with the vacuum self-priming pump.

3. The gas detection device according to claim 2, characterized in that: The device also includes a key selection module, an audible and visual alarm module, a display module, a communication module, and a current output circuit connected to the main control board.

4. The gas detection device according to claim 3, characterized in that: The device also includes a stepper motor driving module connected to the main control board, a stepper motor connected to the output end of the stepper motor driving module, and an incremental encoder connected to the output end of the stepper motor.

5. The gas detection device according to claim 4, characterized in that: The device also includes a power supply module and a power supply voltage stabilizing module. The power supply module is connected to the vacuum self-priming pump, the gas sensor and the stepper motor. The input end of the power supply voltage stabilizing module is connected to the power supply module, and the output end is connected to the signal conditioning circuit and the main control board.

6. The gas detection device according to claim 5, characterized in that: The device also includes a shell and a disc located inside the shell. The multiple detection chambers, the main control board, the PWM speed regulation module, the button selection module, the sound and light alarm module, the display module, the communication module, the current output circuit, the stepper motor drive module, the stepper motor, and the incremental encoder are all configured and installed on a side of the disc away from the bottom plate of the shell. The multiple detection chambers are arranged adjacent to each other, and the cross-section of the detection chamber parallel to the disc is fan-shaped.

7. The gas detection device according to claim 6, characterized in that: The air chamber is installed between one of the detection chambers and the side wall of the housing, and the air chamber can be connected to the detection chamber.

8. The gas detection device according to claim 7, characterized in that: The center of the disk is connected to the center of the bottom plate of the shell through a vertical circular tube, the end of the vertical circular tube close to the bottom plate is fixedly connected to the bottom plate, the end of the vertical circular tube close to the bottom plate is an open end, the end of the vertical circular tube away from the bottom plate is spirally connected to the disk, the end of the vertical circular tube away from the bottom plate is a closed end, the side of the closed end is in contact with the detection chamber, and the side of the closed end has an air outlet at a position corresponding to the air chamber.

9. The gas detection device according to any one of claims 1 to 8, characterized in that: The gas sensor includes at least one of a CO sensor, a H2 sensor, and a NH3 sensor.

10. The gas detection device according to claim 9, characterized in that: The CO sensor is an ME3 type electrochemical sensor, the H2 sensor is a TGS821 hydrogen sensor, and the NH3 sensor is an LGD F200 A type ammonia sensor.

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