In-situ self-zeroing device and method for electrostatic induction dust concentration sensor

Abstract

The present invention relates to an in-situ self-calibration zeroing device and method for an electrostatic induction dust concentration sensor, and belongs to the field of dust concentration sensors. The device includes an electrostatic induction signal monitoring device, a dust extraction fan and a wind tube closing device; the electrostatic induction signal monitoring device includes a metal tube, a metal induction ring and an insulating inner wall; the metal tube is used to form an outer shell shield; the metal induction ring is used to monitor the electrostatic charge of different dust concentrations, convert it into a dust concentration value, and realize real-time monitoring of the dust concentration; the insulating inner wall is used to prevent dust from polluting the metal induction ring. When self-calibrating zero, start the end cover drive motor, drive the wind shield end cover to close the metal tube, turn off the dust extraction fan, so that dust no longer enters the metal tube, and collect the charge data of the metal induction ring at this time, so as to realize the in-situ self-calibration zeroing calibration of the electrostatic induction dust concentration sensor, and further improve the detection accuracy of the dust concentration.

Description

Technical Field

[0001] The invention belongs to the field of dust concentration sensors and relates to an in-situ self-zeroing device and method for an electrostatic induction dust concentration sensor. Background Art

[0002] The principle of the electrostatic induction dust concentration sensor is to generate a signal by using the dynamic charge induction between the dust particles and the probe when they flow through the probe. This sensor uses AC electrostatic technology to monitor the standard deviation of the charge signal, thereby determining the disturbance amount of the AC signal, and determining the dust emission amount by the magnitude of the instantaneous disturbance amount. The working principle of the electrostatic induction dust concentration sensor is based on the behavior of dust particles in the electric field, and the concentration is calculated by measuring the charge change of dust particles in the electrostatic field. This method does not require direct contact with dust, so it is suitable for various environments and application scenarios, and has high sensitivity and accuracy. However, after long-term use on site, the electrostatic induction dust concentration sensor has the problem of measurement value drift. In order to solve this problem, it is necessary to perform zero point self-calibration at intervals.

[0003] The dust concentration sensors currently in use do not have a zeroing function and cannot be zeroed online. The usual way to zero is to pass pure nitrogen or air into the dust monitor, measure the zero point in a dust-free or nearly dust-free environment, and achieve zeroing. This method is more cumbersome. In addition, the installation of the dust monitor sometimes cannot provide the required pure nitrogen or air, so there is no way to achieve zeroing. Although the patent with publication number CN205384204U discloses an online zeroing dust monitor, the zeroing device is added to the outside of the dust measuring device, and the structure is complex, which is inconvenient in actual use. Therefore, there is an urgent need for a portable electrostatic induction dust concentration sensor in-situ self-zeroing device. Summary of the invention

[0004] In view of this, the object of the present invention is to provide an in-situ self-zeroing device and method for an electrostatic induction dust concentration sensor, so as to realize the in-situ self-zeroing calibration of the induction dust concentration sensor and further improve the detection accuracy of dust concentration.

[0005] In order to achieve the above object, the present invention provides the following technical solutions:

[0006] An in-situ self-zeroing device for an electrostatic induction dust concentration sensor, comprising an electrostatic induction signal monitoring device, a dust extraction fan and a wind tube closing device;

[0007] The electrostatic induction signal monitoring device comprises a metal cylinder, a metal induction ring and an insulating inner wall; the metal cylinder is used to form an outer shell shielding cover to minimize the interference of external electromagnetic signals; the metal induction ring is used to monitor the electrostatic charge of different dust concentrations, convert it into a dust concentration value, and realize real-time monitoring of dust concentration; the insulating inner wall is used to prevent dust from polluting the metal induction ring;

[0008] The dust extraction fan is used to draw dust through the metal cylinder (the entire cylindrical device) at a constant speed;

[0009] The air cylinder closing device is used to control whether dust passes through the metal cylinder (the entire cylindrical device).

[0010] Preferably, the wind tube closing device includes an end cover drive motor and a wind shield end cover; the end cover drive motor is installed at the front end of the metal tube, and the rotating shaft of the end cover drive motor is connected to the wind shield end cover to control the opening and closing of the wind shield end cover.

[0011] Preferably, the self-zeroing step of the device is as follows: during self-zeroing, the end cover drive motor is started to drive the wind shield end cover to close the metal cylinder, and the dust extraction fan is turned off to prevent dust from entering the interior of the metal cylinder. At this time, the charge data of the metal induction ring is collected to realize the in-situ self-zeroing calibration of the electrostatic induction dust concentration sensor, thereby further improving the detection accuracy of the dust concentration.

[0012] Preferably, the algorithm for self-zeroing is:

[0013]

[0014] Where D is the diameter of the metal induction ring, mm; d is the width of the metal induction ring, mm; x is the length of the induction tube, mm; y is the induction radius, mm; q is the charge of the dust particles, C; Q is the dust charge induced by the metal induction ring, C; θ is the angle of the metal induction ring in the xy coordinate system;

[0015] When Q is the induction value within a certain period of time < 10 of the lowest induction value -2 At this time, Q is returned to 0, and the dust concentration sensor achieves self-calibration of zero.

[0016] The beneficial effects of the present invention are as follows: the device of the present invention has a simple structure and can realize self-zero calibration of the electrostatic induction dust concentration sensor, effectively solving the measurement value drift problem existing in the field application of the sensor and improving the detection accuracy of the dust concentration.

[0017] Other advantages, objectives and features of the present invention will be described in the following description to some extent, and to some extent, will be obvious to those skilled in the art based on the following examination and study, or can be taught from the practice of the present invention. The objectives and other advantages of the present invention can be realized and obtained through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to make the purpose, technical solutions and advantages of the present invention more clear, the present invention will be described in detail below in conjunction with the accompanying drawings, wherein:

[0019] Figure 1 It is a schematic diagram of the structure of the self-zeroing device of the electrostatic induction dust concentration sensor of the present invention. DETAILED DESCRIPTION

[0020] The following describes the embodiments of the present invention by specific examples, and those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification. The present invention can also be implemented or applied through other different specific embodiments, and the details in this specification can also be modified or changed in various ways based on different viewpoints and applications without departing from the spirit of the present invention. It should be noted that the illustrations provided in the following embodiments only illustrate the basic concept of the present invention in a schematic manner, and the following embodiments and features in the embodiments can be combined with each other without conflict.

[0021] Among them, the drawings are only used for illustrative explanations, and they only represent schematic diagrams rather than actual pictures, and should not be understood as limitations on the present invention. In order to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of actual products. For those skilled in the art, it is understandable that some well-known structures and their descriptions in the drawings may be omitted.

[0022] The same or similar numbers in the drawings of the embodiments of the present invention correspond to the same or similar parts; in the description of the present invention, it should be understood that if the terms "upper", "lower", "left", "right", "front", "rear", etc. indicate the orientation or position relationship, they are based on the orientation or position relationship shown in the drawings, which 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 operate in a specific orientation. Therefore, the terms describing the position relationship in the drawings are only used for illustrative purposes and cannot be understood as limiting the present invention. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to specific circumstances.

[0023] See also Figure 1 The present invention provides a self-calibration zero calibration device for an electrostatic induction dust concentration sensor, such as Figure 1As shown in FIG. 1 , the device is composed of an electrostatic induction signal monitoring device, a dust extraction fan and a wind tube closing device. The electrostatic induction signal monitoring device is composed of a metal tube, a metal induction ring and an insulating inner wall; the function of the metal tube is to form an outer shell shielding cover to minimize the interference of external electromagnetic signals; the metal induction ring is used to monitor the electrostatic charge of different dust concentrations, convert it into a dust concentration value, and realize real-time monitoring of dust concentration; the insulating inner wall is used to prevent dust from polluting the induction ring. The dust extraction fan can be a waterproof and dustproof axial flow fan, which is used to draw dust through the entire cylindrical device at a constant speed. The wind tube closing device is composed of an end cover drive motor and a wind shield end cover, and the wind shield end cover and the rotating shaft of the end cover drive motor are connected together.

[0024] The steps for self-calibration of electrostatic induction dust concentration sensor are as follows:

[0025] The charge sensing unit adopts a powered motor to extract dust. An end cover driving motor is installed at the front end of the inductive metal cylinder to disrupt the dust flow and increase the static electricity of the dust. During self-calibration to zero, the windshield end cover is driven to close the inductive metal cylinder and the dust extraction fan to prevent dust from entering the metal inductive cylinder. At this time, the charge data of the inductive metal induction ring is collected to realize the in-situ self-calibration to zero the inductive dust concentration sensor, further improving the detection accuracy of dust concentration.

[0026] The algorithm for self-calibration is:

[0027]

[0028] Where D is the diameter of the metal induction ring, mm; d is the width of the metal induction ring, mm; x is the length of the induction tube, mm; y is the induction radius, mm; q is the charge of the dust particles, C; Q is the dust charge induced by the metal induction ring, C; θ is the angle of the metal induction ring in the xy coordinate system;

[0029] When Q is the induction value within a certain period of time < 10 of the lowest induction value -2 At this time, Q is returned to 0, and the dust concentration sensor achieves self-calibration of zero.

[0030] Finally, it should be noted that the above embodiments are only used to illustrate the technical solution of the present invention rather than to limit it. Although the present invention has been described in detail with reference to the preferred embodiments, those skilled in the art should understand that the technical solution of the present invention can be modified or replaced by equivalents without departing from the purpose and scope of the technical solution, which should be included in the scope of the claims of the present invention.

Claims

1. An in-situ self-zeroing device for an electrostatic induction dust concentration sensor, characterized in that: The device includes an electrostatic induction signal monitoring device, a dust extraction fan and a wind tube closing device; The electrostatic induction signal monitoring device comprises a metal cylinder, a metal induction ring and an insulating inner wall; the metal cylinder is used to form a shell shielding cover to reduce the interference of external electromagnetic signals; the metal induction ring is used to monitor the electrostatic charge of different dust concentrations, convert it into a dust concentration value, and realize real-time monitoring of dust concentration; the insulating inner wall is used to prevent dust from polluting the metal induction ring; The dust extraction fan is used to draw dust through the metal cylinder at a constant speed; The wind tube closing device is used to control whether dust passes through the metal tube; The algorithm for self-calibration is: in, D is the diameter of the metal induction ring; d is the width of the metal induction loop; x is the length of the sensing tube; y is the induction radius; q is the charge of the dust particles; Q It is the dust charge induced by the metal induction ring; is the angle of the metal induction ring in the xy coordinate system; when Q The induction value is less than 10% of the lowest induction value within a certain period of time. -2 , at this time will Q When the dust concentration sensor is reset to 0, it can achieve self-calibration.

2. The electrostatic induction dust concentration sensor in-situ self-zeroing device according to claim 1 is characterized in that: The wind tube closing device includes an end cover driving motor and a windshield end cover; the end cover driving motor is installed at the front end of the metal tube, and the rotating shaft of the end cover driving motor is connected to the windshield end cover to control the opening and closing of the windshield end cover.

3. The in-situ self-zeroing device for an electrostatic induction dust concentration sensor according to claim 1 or 2, characterized in that: The self-calibration steps of the device are as follows: during self-calibration, the end cover drive motor is started to drive the wind shield end cover to close the metal cylinder, and the dust extraction fan is turned off to prevent dust from entering the inside of the metal cylinder. At this time, the charge data of the metal induction ring is collected to realize the in-situ self-calibration of the electrostatic induction dust concentration sensor, thereby improving the detection accuracy of dust concentration.

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