CN111426278A - A kind of dynamic measurement method of blade tip clearance of mining fan - Google Patents

Abstract

The invention discloses a method for dynamically measuring the blade tip clearance of a mining fan in the technical field of coal mine safety monitoring and monitoring. The method comprises the following steps: constructing a dynamic measurement and analysis system for the blade tip clearance of the mining fan; , adjust the triangulation bracket to determine the best position of the 2D laser profile sensor in the X and Z directions; adjust and determine the position of the triangulation bracket in the Y direction; optimize the measurement attitude of the 2D laser profile sensor and calculate the gap measurement results; improve the blade tip The measurement accuracy of the clearance meets the requirements of dynamic measurement of the blade tip clearance; according to the geometric characteristics of the blade tip clearance, the blade tip clearance identification algorithm is used to complete the dynamic extraction and evaluation of the blade tip clearance of the mining fan, which is a good solution to the mining fan's tip clearance. The dynamic measurement of the blade tip clearance under the running state of the fan provides an effective technical solution for the real-time online monitoring of the blade tip clearance at the coal mine site.

Description

A kind of dynamic measurement method of blade tip clearance of mining fan

technical field

The invention relates to the technical field of coal mine safety monitoring and monitoring, in particular to a dynamic measurement method for a blade tip clearance of a mine fan.

Background technique

Blade tip clearance refers to the minimum radial distance between the fan rotor blades and the casing (see Figure 1). It is an important technical parameter related to the performance and safety of the fan. Too large or too small blade tip clearance will seriously affect ventilation. The operation efficiency and safety and stability of the machine. Tip clearance detection is an important requirement for optimizing fan performance and ensuring the safe and stable operation of the fan. In the national safety production industry standard, the importance and technical specifications of the tip clearance detection of mining fans are clearly explained.

At present, the detection of the blade tip clearance of mining fans is mainly realized by the static measurement method, that is, when the fan is stationary, the detection and evaluation of the blade tip clearance are completed by using a feeler gauge or an instrument. The static measurement method has the disadvantages of poor real-time performance, one-sided evaluation results, and low level of intelligence. It is only suitable for offline sampling inspection of blade tip clearance, and cannot meet the technical requirements of real-time online monitoring and safety warning of blade tip clearance of mining fans. On-line dynamic detection of blade tip clearance of mining fans has always been an important requirement for coal mine safety monitoring, and it is also a difficult problem. The so-called online dynamic detection is to detect and analyze the changing law of the blade tip clearance in real time under the running state of the fan, to detect abnormalities in time and take measures to prevent accidents. The dynamic measurement method has obvious advantages in real-time, scientific and intelligent aspects. Based on this, the present invention designs a dynamic measurement method for the blade tip clearance of a mining fan to solve the above problems.

SUMMARY OF THE INVENTION

The purpose of the present invention is to provide a dynamic measurement method for the blade tip clearance of a mining fan, so as to solve the problems raised in the above background technology.

In order to achieve the above purpose, the present invention provides the following technical solutions: a dynamic measurement method for the blade tip clearance of a mining fan, comprising the following steps:

S1: Build a dynamic measurement and analysis system for the blade tip clearance of a mining fan, which includes a triangulation support, a four-degree-of-freedom attitude adjustment mechanism, a 2D laser profile sensor and a measurement and control computer;

S2: Select the 3 o'clock azimuth gap as the measurement object, adjust the triangulation bracket, and determine the best position of the 2D laser profile sensor in the X and Z directions;

S3: Adjust and determine the position of the triangulation bracket in the Y direction;

S4: Optimize the attitude measurement of the 2D laser profile sensor, and calculate the gap measurement result;

S5: Improve the measurement accuracy of the blade tip clearance and meet the requirements of dynamic measurement of the blade tip clearance;

S6: According to the geometric characteristics of the blade tip clearance, the blade tip clearance identification algorithm is used to complete the dynamic extraction and evaluation of the blade tip clearance of the mining fan.

Further, the 2D laser profile sensor is signal-connected to the measurement and control computer, the four-DOF attitude adjustment mechanism is detachably fixed on the top of the triangulation bracket, and the 2D laser profile sensor is detachably fixed on the four-DOF attitude adjustment mechanism.

Further, the triangulation bracket is used to adjust the positional relationship between the measurement analysis system and the measured gap, and is used to establish the measurement coordinate system, and the four-degree-of-freedom attitude adjustment mechanism is used for the optimization of the sensor measurement attitude. Flexible adjustment of the four degrees of freedom of forward and backward, pitch and yaw to optimize the gap measurement results. The 2D laser profile sensor is used for high-precision dynamic acquisition of the geometric information of the blade tip gap. The sensor uses a line laser to project on the surface of the measured object. Output the position data of the two axes of the light curtain width direction and distance direction. One sampling can obtain the two-dimensional coordinate information of the measured object. The measurement and control computer is loaded with special measurement and analysis software to complete the control of the measurement process, data transmission and results. processing and analysis.

Further, in the step S3, the technical parameters of the 2D laser profile sensor are used to adjust the position of the triangulation support in the Y direction, and by optimizing the measurement position of the 2D laser profile sensor, the distance between the measured gap and the 2D laser profile sensor is equal to the 2D laser profile. The sensor working distance to determine the optimal position of the 2D laser profile sensor in the Y direction.

Further, in the step S4, the pitch or yaw adjustment of the 2D laser profile sensor is used to improve the quality of the gap image, thereby improving the accuracy of the gap measurement. ) calculation, where δ _m is the gap measurement result, δ' _m is the gap measurement value after attitude optimization, k is the calibration coefficient, and the formula is:

δ _m = k*δ' _m (1)

Further, in the step S5, by optimizing the photographing range, sampling frequency, light receiving amount, photographing mode and contour extraction algorithm of the 2D laser profile sensor, the measurement accuracy of the tip clearance is improved to meet the requirements of dynamic measurement of the tip clearance.

Compared with the prior art, the beneficial effects of the present invention are: the present invention adopts the 2D laser profile sensor to dynamically collect the geometric information of the blade tip gap, and has the advantages of non-contact, high precision, high dynamic response, strong anti-interference ability and high level of intelligence. Then, through the technology of projection transformation, contour extraction, and data processing, the measurement results of the blade tip clearance are analyzed in real time, which solves the problem of dynamic measurement of the blade tip clearance under the operating state of the mining fan, which is the real-time measurement of the blade tip clearance at the coal mine site. Online monitoring provides effective technical solutions.

Description of drawings

In order to illustrate the technical solutions of the embodiments of the present invention more clearly, the following briefly introduces the accompanying drawings used in the description of the embodiments. Obviously, the drawings in the following description are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained from these drawings without any creative effort.

Fig. 1 is the definition diagram of the existing blade tip clearance;

Fig. 2 is the dynamic measurement and analysis system of the blade tip clearance of the mining fan of the present invention;

3 is a schematic diagram of the angular position of the 2D laser profile sensor of the present invention;

FIG. 4 is a schematic diagram of the gap selection and sensor position optimization in the X and Z directions according to the present invention;

FIG. 5 is a schematic diagram of the position optimization of the sensor in the Y direction according to the present invention;

Fig. 6 is the flow chart of the tip clearance identification algorithm of the present invention;

Fig. 7 is the original measurement image of the dynamic gap of the present invention;

8 is a schematic diagram of the dynamic measurement result of the tip clearance of the present invention;

FIG. 9 is a flow chart of the method of the present invention.

In the accompanying drawings, the list of components represented by each number is as follows:

Triangulation bracket 1, four-degree-of-freedom attitude adjustment mechanism 2, 2D laser profile sensor 3.

Detailed ways

The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, but not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

In the description of the present invention, it should be understood that the terms "upper", "lower", "front", "rear", "left", "right", "top", "bottom", "inside", " The orientation or positional relationship indicated by "outside" 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 indicated device or element must have a specific orientation, so as to The specific orientation configuration and operation are therefore not to be construed as limitations of the present invention.

Please refer to Figures 1-9, the present invention provides a technical solution: a dynamic measurement method for the blade tip clearance of a mining fan, comprising the following steps:

S1: Build a dynamic measurement and analysis system for the blade tip clearance of a mining fan, which includes a triangulation support 1, a four-degree-of-freedom attitude adjustment mechanism 2, a 2D laser profile sensor 3 and a measurement and control computer;

S2: Select the 3 o’clock azimuth gap as the measurement object, adjust the triangulation bracket 1, determine the best position of the 2D laser profile sensor 3 in the X and Z directions, simplify the measurement model, and optimize the measurement optical path;

S3: Adjust and determine the position of the triangulation bracket in the Y direction;

S4: Optimize the measurement attitude of the 2D laser profile sensor 3, and calculate the gap measurement result;

S5: Improve the measurement accuracy of the blade tip clearance and meet the requirements of dynamic measurement of the blade tip clearance;

S6: According to the geometric characteristics of the blade tip clearance, the blade tip clearance identification algorithm is used to complete the dynamic extraction and evaluation of the blade tip clearance of the mining fan.

Among them, the 2D laser profile sensor 3 is connected with the signal of the measurement and control computer, the four-degree-of-freedom attitude adjustment mechanism 2 is detachably fixed on the top of the triangulation bracket 1, and the 2D laser profile sensor 3 is detachably fixed on the four-degree-of-freedom attitude adjustment mechanism 2.

The triangulation bracket 1 is used to adjust the positional relationship between the measurement analysis system and the measured gap, and is used to establish the measurement coordinate system. The four-degree-of-freedom attitude adjustment mechanism 2 is used to optimize the sensor measurement attitude. The flexible adjustment of the four degrees of freedom of the pendulum can optimize the gap measurement results. The 2D laser profile sensor 3 is used for high-precision dynamic acquisition of the geometric information of the blade tip gap. The position data of the two axes in the distance direction can obtain the two-dimensional coordinate information of the measured object in one sampling. It has the technical characteristics of non-contact, high precision and high dynamic response, which solves the technical problem of dynamic measurement of tip clearance well. The measurement and control computer is loaded with special measurement and analysis software to complete the control of the measurement process, data transmission, and result processing and analysis.

In step S3, the technical parameters of the 2D laser profile sensor 3 are used to adjust the position of the triangulation support 1 in the Y direction, and by optimizing the measurement position of the 2D laser profile sensor 3, the distance between the measured gap and the 2D laser profile sensor 3 is equal to the 2D laser profile sensor. 3 working distance, so as to determine the best position of 2D laser profile sensor 3 in the Y direction,

In step S4, the pitch or yaw adjustment of the 2D laser profile sensor 3 is used to improve the quality of the gap image, thereby improving the accuracy of the gap measurement. After the measurement posture of the 2D laser profile sensor 3 is optimized, the gap measurement result can be calculated according to formula (1), where, δ _m is the gap measurement result, δ' _m is the gap measurement value after attitude optimization, k is the calibration coefficient, the formula is:

δ _m = k*δ' _m (1)

In step S5, by optimizing the photographing range, sampling frequency, light receiving amount, photographing mode and contour extraction algorithm of the 2D laser profile sensor 3, the measurement accuracy of the tip clearance is improved, and the requirements for dynamic measurement of the tip clearance are met.

A specific application of this embodiment is:

Referring to Figure 2, the dynamic measurement and evaluation of the blade tip clearance under the operating state of the mining fan is realized by the dynamic measurement system of the blade tip clearance based on the 2D laser profile sensor 3. The system consists of a triangulation support 1 and a four-degree-of-freedom attitude adjustment mechanism 2. , 2D laser profile sensor 3 and measurement and control computer.

Referring to FIG. 2 , the triangulation support 1 is responsible for the adjustment of the positional relationship between the measurement system and the measured gap, and is used for the establishment of the measurement coordinate system.

Referring to FIG. 2 , the four-degree-of-freedom attitude adjustment mechanism 2 is responsible for the optimization of the measurement attitude of the 2D laser profile sensor 3, and optimizes the gap measurement result through flexible adjustment of the four degrees of freedom of height, front and rear, pitch and yaw.

Referring to FIG. 3 , the 2D laser profile sensor 3 is used to achieve high-precision dynamic acquisition of the geometric information of the blade tip gap.

Referring to Figure 4, select the 3 o'clock position of the annular gap as the measurement object, and adjust the triangulation bracket 1 according to the selected gap, until the 2D laser profile sensor 3 collects a clear and complete image of the tip gap, so as to determine that the sensor is at X. , the best position in the Z direction.

Referring to Figure 5, according to the technical parameters of the 2D laser profile sensor 3, adjust the position of the triangulation support 1 in the Y direction, and optimize the measurement position of the 2D laser profile sensor 3, so that the distance between the measured gap and the 2D laser profile sensor 3 is equal to the 2D laser profile sensor. 3. Working distance, so as to determine the best position of 2D laser profile sensor 3 in the Y direction.

Referring to Figure 2, the pitch or yaw adjustment of the 2D laser profile sensor 3 improves the quality of the gap image, thereby improving the accuracy of the gap measurement; The measurement results are calculated according to formula (1).

Then, by optimizing the sensor's photographing range, sampling frequency, light receiving amount, photographing mode and contour extraction algorithm, the measurement accuracy of the tip clearance is improved to meet the requirements of dynamic measurement of the tip clearance.

Finally, according to the geometric characteristics of the tip clearance, the tip clearance identification algorithm shown in Figure 6 is used to complete the dynamic extraction and evaluation of the tip clearance of the mining fan. The dynamic measurement results of the tip clearance are shown in Figure 8.

The working principle of the present invention is:

Referring to Fig. 2, when utilizing the present invention to dynamically measure the blade tip clearance of the mining fan, first the measurement system is installed in front of the running fan; further, with reference to Fig. 4, the clearance at the 3 o'clock position is selected as the measurement object, and adjusted The position of the triangulation bracket 1 in the X and Z directions is measured until the 2D laser profile sensor 3 collects a clear image of the tip clearance, and the establishment of the measurement coordinate system O-XYZ is completed; further, referring to FIG. 5 , according to the 2D laser profile sensor 3 Technical parameters, adjust the position of the triangulation bracket 1 in the Y direction, so that the distance between the measured gap and the 2D laser profile sensor 3 is equal to the working distance of the sensor; further, adjust the 2D laser profile sensor 3 to measure the attitude, optimize the sensor settings, until the measurement and control computer A stable, clear and ideal gap measurement contour is collected on the loaded measurement software; finally, referring to Figure 6, the coordinate data of the gap contour is collected, data processing, feature extraction, gap calculation and evaluation are performed.

In the description of this specification, description with reference to the terms "one embodiment," "example," "specific example," etc. means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one aspect of the present invention. in one embodiment or example. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

The above-disclosed preferred embodiments of the present invention are provided only to help illustrate the present invention. The preferred embodiments do not exhaust all the details, nor do they limit the invention to only the described embodiments. Obviously, many modifications and variations are possible in light of the content of this specification. The present specification selects and specifically describes these embodiments in order to better explain the principles and practical applications of the present invention, so that those skilled in the art can well understand and utilize the present invention. The present invention is to be limited only by the claims and their full scope and equivalents.

Claims (6)

1. a mine fan tip clearance dynamic measurement method, is characterized in that, comprises the steps: S1: construct a dynamic measurement and analysis system for the blade tip clearance of a mining fan, which includes a triangulation support (1), a four-degree-of-freedom attitude adjustment mechanism (2), a 2D laser profile sensor (3) and a measurement and control computer; S2: Select the 3 o'clock azimuth gap as the measurement object, adjust the triangulation bracket (1), and determine the optimal position of the 2D laser profile sensor (3) in the X and Z directions; S3: Adjust and determine the position of the triangulation bracket in the Y direction; S4: optimize the 2D laser profile sensor (3) to measure the attitude, and calculate the gap measurement result; S5: Improve the measurement accuracy of the blade tip clearance and meet the requirements of dynamic measurement of the blade tip clearance; S6: According to the geometric characteristics of the blade tip clearance, the blade tip clearance identification algorithm is used to complete the dynamic extraction and evaluation of the blade tip clearance of the mining fan. 2. a kind of mining fan blade tip clearance dynamic measurement method according to claim 1 is characterized in that: described 2D laser profile sensor (3) is connected with measurement and control computer signal, and described four-degree-of-freedom attitude adjustment mechanism ( 2) Removably fixed on the top of the triangulation bracket (1), the 2D laser profile sensor (3) is detachably fixed on the four-degree-of-freedom attitude adjustment mechanism (2). 3. A kind of dynamic measuring method of blade tip clearance of mining fan according to claim 1, it is characterized in that: described triangulation support (1) is used for the positional relationship adjustment between measurement analysis system and measured clearance, uses For the establishment of the measurement coordinate system, the four-degree-of-freedom attitude adjustment mechanism (2) is used to optimize the measurement attitude of the sensor, and optimize the gap measurement result through flexible adjustment of the four degrees of freedom of height, front and rear, pitch and yaw, and the said The 2D laser profile sensor (3) is used for high-precision dynamic acquisition of the geometric information of the blade tip gap. The sensor uses a line laser to project the surface of the object to be measured, and outputs the position data of the two axes of the width direction of the light curtain and the distance direction. One sampling can The two-dimensional coordinate information of the measured object is acquired, and special measurement and analysis software is loaded on the measurement and control computer to complete the control of the measurement process, data transmission, and result processing and analysis. 4. a kind of mining fan blade tip clearance dynamic measurement method according to claim 1, is characterized in that: utilize 2D laser profile sensor (3) technical parameter in described step S3, adjust triangulation support (1) in The position in the Y direction is determined by optimizing the measurement position of the 2D laser profile sensor (3) so that the distance between the measured gap and the 2D laser profile sensor (3) is equal to the working distance of the 2D laser profile sensor (3), thereby determining the 2D laser profile sensor (3). ) in the best position in the Y direction. 5. a kind of mining fan blade tip clearance dynamic measurement method according to claim 1, is characterized in that: utilize 2D laser profile sensor (3) pitch or yaw adjustment in described step S4, improve clearance image quality, Thereby, the accuracy of gap measurement is improved. After the 2D laser profile sensor (3) measures the attitude optimization, the gap measurement result can be calculated according to formula (1), where δ _m is the gap measurement result, and δ' _m is the gap measurement after the attitude optimization. value, k is the calibration coefficient, the formula is: δ _m = k*δ' _m (1) 6. A kind of dynamic measuring method of blade tip clearance of mining fan according to claim 1, it is characterized in that: in described step S5, by optimizing 2D laser profile sensor (3) photographing range, sampling frequency, amount of light received, photographing Pattern and contour extraction algorithm to improve the measurement accuracy of tip clearance and meet the requirements of dynamic measurement of tip clearance.

Images