Tunnel construction dust detection device

Abstract

The utility model relates to a kind of tunnel construction dust detection devices including sampling gas path, dust detector based on light signal and signal transmitter;Sampling gas path, including air inlet pipeline, optical observation cavity and air outlet pipeline;Dust detector, including the light source of setting at the optical observation cavity of sampling gas path, light path and sampling gas path are orthogonal;Area array photoelectric detector is connected with transmitter electric signal;Signal transmitter, including radio frequency antenna, for the signal of area array photoelectric detector received is sent to the receiving end of collected data.The tunnel construction dust detection device provided by the utility model realizes the real-time dust detection of anti-interference by sealing, independent sampling gas path and independent, isolated light signal path relative to sampling gas path.Optimized scheme, detection laser is shaped into narrow light spot, adopts double-wavelength detection, cooperates with impact type pre-separator, realizes the dust detection resolution improvement of different dimensions such as detection time, detection granularity.

Description

Technical Field

[0001] This utility model belongs to the field of dust detection, and more specifically, relates to a dust detection device for tunnel construction. Background Technology

[0002] Dust monitoring during tunnel construction is a crucial aspect of occupational health and safety. Currently, this field primarily employs sampling and detection techniques such as membrane weighing. These methods have significant limitations: poor real-time performance prevents the capture of dynamic fluctuations in dust concentration, they are complex to operate requiring specialized personnel, and they are difficult to implement in hazardous areas. While non-sampling techniques such as light scattering are gradually being adopted, existing sensors still face challenges in complex tunnel environments, including humidity-induced measurement accuracy issues and insufficient particle size resolution. Particularly noteworthy is the general lack of intelligent analysis capabilities in traditional monitoring systems; they can only provide basic data acquisition functions and cannot achieve dynamic assessment of dust risks or multi-level early warning systems. This directly impacts the timeliness and effectiveness of dust control in tunnel construction.

[0003] The development of dust monitoring technology has evolved from offline sampling to online detection. Early methods relied primarily on filter membrane weighing for laboratory analysis, which had long measurement cycles and could not reflect real-time operating conditions. With advancements in optical technology, sensors based on the principle of light scattering became widespread, achieving minute-level response and continuous monitoring. In recent years, information technology has driven the development of monitoring systems towards networking, resulting in preliminary solutions integrating data acquisition and transmission functions. However, existing sensor hardware has not yet overcome technical bottlenecks in terms of interference resistance and particle size resolution accuracy. Utility Model Content

[0004] In view of the above-mentioned defects or improvement needs of the existing technology, this utility model provides a tunnel construction dust detection device. Its purpose is to isolate the optical signal from the detection sample, realize a stable tunnel construction dust detection device based on optical detection, and provide tunnel construction dust detection with strong anti-interference ability, thereby solving the technical problem of insufficient anti-interference of existing dust monitoring.

[0005] To achieve the above objectives, according to one aspect of the present invention, a dust detection device for tunnel construction is provided, comprising a sampling gas path, a dust detector based on optical signals, and a signal transmitter;

[0006] The sampling gas path includes an inlet pipe, an optical observation cavity, and an outlet pipe;

[0007] The dust detector includes a light source disposed at the optical observation cavity of the sampling gas path, the light source optical path being orthogonal to the sampling gas path; the area array photodetector is electrically connected to the transmitter.

[0008] The signal transmitter includes a radio frequency antenna for transmitting the received signal from the area array photodetector to the data receiving end.

[0009] Preferably, the dust detector of the dust tunnel construction dust early warning device is a multi-wavelength light scattering tunnel dust particle size detector; its light source includes a laser diode, an aspherical lens and a cylindrical mirror in sequence according to the optical path direction, so that the illumination spot of the optical observation cavity is a narrow spot with a flat top distribution, and the length direction of the narrow spot is orthogonal to the airflow direction.

[0010] Preferably, in the dust warning device for tunnel construction, the laser diode emits wavelengths of 375nm and 808nm.

[0011] Preferably, the photodetector of the dust tunnel construction dust early warning device is a photomultiplier tube or an avalanche photodiode.

[0012] Preferably, the photoelectric detector of the dust tunnel construction dust early warning device is a surface array photoelectric sensor array.

[0013] Preferably, the photoelectric detector of the dust tunnel construction dust early warning device is a dual-wavelength detector used to detect 375nm scattered light and 808nm scattered light.

[0014] Preferably, the dust warning device for tunnel construction includes a temperature and humidity sensor installed in the optical observation cavity, and the temperature and humidity sensor is electrically connected to the signal transmitter.

[0015] Preferably, the dust warning device for tunnel construction includes a constant flow air pump installed in the inlet or outlet pipe to maintain a stable sampling flow rate, with a wind speed of 2-3.5 m / s in the sampling air path.

[0016] Preferably, in the dust early warning device for dust tunnel construction, the inner wall of the sampling gas path has a conductive metal coating, and the conductive metal coating is grounded.

[0017] Preferably, the dust warning device for tunnel construction includes an inertial impact pre-separator in its air intake pipe. Overall, compared with the prior art, the above technical solution conceived by this utility model can achieve the following beneficial effects:

[0018] The road construction dust detection device provided by this utility model achieves real-time dust detection with anti-interference through a sealed, independent sampling gas path and an independent, isolated optical signal path relative to the sampling gas path. In a preferred embodiment, the detection laser is shaped into a narrow spot, dual-wavelength detection is employed, and an impact-type pre-separator is used, thereby improving dust detection resolution in different dimensions such as detection time and particle size. Attached Figure Description

[0019] Figure 1 This is a schematic diagram of the optical path structure of the tunnel construction dust detection and early warning device provided in the embodiment. Detailed Implementation

[0020] To make the objectives, technical solutions, and advantages of this utility model clearer, the following detailed description is provided in conjunction with embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the scope of this utility model. Furthermore, the technical features involved in the various embodiments of this utility model described below can be combined with each other as long as they do not conflict with each other.

[0021] The tunnel construction dust detection and early warning device provided by this utility model is installed in the construction environment; it includes a sampling gas path, a dust detector based on light signals, and a signal transmitter.

[0022] The sampling gas path consists of an inlet pipe, an optical observation chamber, and an outlet pipe. The inlet and outlet pipes are respectively located at both ends of the optical observation chamber, forming a continuous dust airflow channel. Preferably, the inlet pipe is equipped with an inertial impact pre-separator, which includes three stages of inertial impact plates with different apertures for graded interception and detection of dust particles of different sizes. Preferably, the inner wall of the sampling gas path has a conductive metal coating, which is grounded to prevent electrostatic adsorption of dust. A constant flow pump is located in either the inlet or outlet pipe, and a vibration-damping coupling component is provided between the pump body and the pipe to reduce vibration noise. During operation, the gas velocity in the sampling gas path is 2 m / s to 3.5 m / s.

[0023] The optical observation cavity is a rectangular, sealed chamber with transparent quartz windows on its two orthogonal sides. The light source for the dust detector is located on one side of the cavity and consists of a laser diode emitter, an aspherical collimating lens, and a cylindrical lens. The lens group shapes the laser beam into a narrow, flat-topped spot, with the spot's length direction orthogonal to the airflow direction, ensuring both the irradiated surface area and detection resolution. A photodetector, using a photomultiplier tube (PMT) or an avalanche photodiode (APD), is installed on the other orthogonal side surface, preferably an array of photodetectors with a 90° lateral scattering detection angle to effectively collect forward scattered light signals. Preferably, the photodetector is a dual-wavelength detector used to detect 405nm and 850nm scattered light. Preferably, a temperature and humidity sensor is installed inside the optical observation cavity, and this sensor is electrically connected to the signal transmitter.

[0024] The signal transmitter includes a radio frequency antenna for transmitting the received signal from the area array photodetector to the data receiving end.

[0025] The following is an example:

[0026] The tunnel construction dust detection and early warning device provided in this embodiment is installed in the construction environment, such as... Figure 1 As shown, it includes a sampling gas path, a dust detector based on optical signals, and a signal transmitter.

[0027] The sampling gas path consists of an inlet pipe, an optical observation chamber, and an outlet pipe. The inlet and outlet pipes are respectively located at both ends of the optical observation chamber, forming a continuous dust airflow channel. An inertial impact pre-separator is installed at the inlet of the inlet pipe. This pre-separator includes three stages of inertial impact plates with different apertures, used to grade and trap dust particles of different sizes for graded detection. In this embodiment, the impact pre-separator can grade and collect samples of different particle sizes such as PM10, PM2.5, and PM1. The inner wall of the sampling gas path has a conductive metal coating, which is grounded to prevent electrostatic adsorption of dust. A constant flow pump (1.0 CFM) is installed in the outlet pipe to maintain a stable sampling flow rate. A vibration damping coupling component is provided between the pump body and the pipe to reduce vibration noise. In this embodiment, the integrated airflow compensation module maintains the wind speed at 2-3.5 m / s. Depending on the tunnel ventilation speed, such as in low wind speed mode (0-2 m / s), an annular air curtain is activated to assist in suction (pressure difference maintained at 500 Pa) to suppress particle adhesion to the probe caused by Brownian motion; in high wind speed mode (>3.5 m / s), gradient negative pressure compensation is activated, and a reverse pressure wave is generated in the sampling channel through a piezoelectric ceramic valve (response time <50 ms) to counteract particle escape caused by airflow shear force (escape rate reduced from 12% to 3%).

[0028] The optical observation cavity is a rectangular, sealed chamber with transparent quartz windows on its two orthogonal sides. The light source for the dust detector is located on one side of the chamber and consists of a laser diode emitter, an aspherical collimating lens, and a cylindrical lens. The aspherical collimating lens and the cylindrical lens form the optical path. In this embodiment, a dual-wavelength laser (375nm) and a near-infrared laser (808nm) are used as the light source. The lens group shapes the laser beam into a narrow, flat-topped spot (approximately 0.5×5mm) to ensure uniform light intensity coverage of the dust sampling area. The length direction of the spot is orthogonal to the airflow direction, ensuring both the irradiated surface area and the detection resolution. This embodiment employs digital lock-in amplification technology and uses a pulsed laser source (1kHz) to suppress ambient light interference. A photodetector is installed on the other orthogonal side. In this embodiment, an avalanche photodiode (APD) array is used, which can detect dust particles in the 0.1-100μm particle size range. The lateral scattering detection angle is 90°, effectively acquiring forward scattered light signals. In this embodiment, the photodetector is a dual-wavelength detector used to detect 375nm and 808nm scattered light, and the particle size distribution is calculated by the ratio of scattering intensities at different wavelengths. A temperature and humidity sensor is installed inside the optical observation cavity, and this sensor is electrically connected to the signal transmitter. The dual temperature and humidity sensors correct for measurement errors caused by steam humidity in real time. This embodiment incorporates multi-point temperature compensation to adapt to a working temperature range of -10℃ to 50℃ within the tunnel.

[0029] In this embodiment, the sampling gas path integrates a self-cleaning function, configured with periodic reverse airflow pulses to remove dust accumulation in the optical observation cavity. The optical observation cavity has an IP67 protection rating, and maintains a slight positive pressure (+50Pa) internally to prevent dust intrusion.

[0030] The signal transmitter includes a radio frequency antenna, used to transmit the received signal from the area array photodetector to the data receiving end. The collected scattered light signal is used to establish a Mie scattering theoretical model database, and a BP neural network algorithm is used to achieve nonlinear correction of the scattered signal-mass concentration.

[0031] The tunnel construction dust detection and early warning device provided in this embodiment outputs a mass concentration (0-1000 mg / m³). 3 ), Quantity concentration (0-10^6 particles / cm³) 3 The particle size distribution (PM1, PM2.5, PM10) and response time are <3 seconds, meeting the occupational exposure limit monitoring requirements of GBZ 2.1-2019.

[0032] Those skilled in the art will readily understand that the above description is merely a preferred embodiment of the present utility model and is not intended to limit the present utility model. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present utility model should be included within the protection scope of the present utility model.

Claims

1. A dust detection device for tunnel construction, characterized in that, This includes a sampling gas path, a light-based dust detector, and a signal transmitter; The sampling gas path includes an inlet pipe, an optical observation cavity, and an outlet pipe; The dust detector includes a light source and an array photodetector disposed at the optical observation cavity of the sampling gas path, wherein the light source optical path is orthogonal to the sampling gas path; and the array photodetector is electrically connected to the transmitter. The signal transmitter includes a radio frequency antenna for transmitting the received signal from the area array photodetector to the data receiving end.

2. The tunnel construction dust detection device as described in claim 1, characterized in that, The dust detector is a multi-wavelength light scattering tunneling dust particle size detector; its light source includes a laser diode, an aspherical lens, and a cylindrical mirror in sequence according to the optical path direction, so that the illumination spot of the optical observation cavity is a narrow spot with a flat top distribution, and the length direction of the narrow spot is orthogonal to the airflow direction.

3. The tunnel construction dust detection device as described in claim 2, characterized in that, The laser diode emits wavelengths of 375nm and 808nm.

4. The tunnel construction dust detection device as described in claim 1, characterized in that, The photodetector is a photomultiplier tube or an avalanche photodiode.

5. The tunnel construction dust detection device as described in claim 4, characterized in that, The photodetector is a planar array of photodetectors.

6. The tunnel construction dust detection device as described in claim 1, characterized in that, The photodetector is a dual-wavelength detector used to detect 375nm scattered light and 808nm scattered light.

7. The tunnel construction dust detection device as described in claim 1, characterized in that, A temperature and humidity sensor is installed inside the optical observation cavity, and the temperature and humidity sensor is electrically connected to the signal transmitter.

8. The tunnel construction dust detection device as described in claim 1, characterized in that, The sampling gas path includes a constant flow pump installed in the inlet or outlet pipe to maintain a stable sampling flow rate, with a wind speed of 2-3.5 m / s in the sampling gas path.

9. The tunnel construction dust detection device as described in claim 1, characterized in that, The inner wall of the sampling gas path has a conductive metal coating, and the conductive metal coating is grounded.

10. The tunnel construction dust detection device as described in claim 1, characterized in that, The intake pipe is equipped with an inertial impact pre-separator.

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