A hydraulic support and coal winning machine anti-collision early warning method

Abstract

The application discloses a kind of about coal winning machine rocker arm and the anti-collision early warning method of hydraulic support roof beam. Its characterized in that the method does not need additional multiple sensors, only through the data provided by the height sensor of coal winning machine itself, inclination sensor, shaft encoder and the position sensor, height sensor etc. of hydraulic support, issue early warning instruction to two kinds of equipment in combination with working face centralized control system, reach the anti-collision effect between two kinds of equipment. The method is low in investment cost, can judge the mutual positional relationship of coal winning machine and hydraulic support in real time, and effectively early warning before collision danger occurs, with high reliability, high maintainability.

Description

Technical Field

[0001] This invention belongs to the field of intelligent mining in fully mechanized mining faces, and particularly relates to an anti-collision early warning method applicable to coal mining machines and hydraulic supports in fully mechanized mining faces during the mining process. Background Technology

[0002] In the production process of fully mechanized longwall mining faces in underground coal mines, the smooth coordination of mining equipment is crucial to ensuring high production and efficiency. During actual production, factors such as unpredictable coal seam conditions, complex and variable geological structures of the roof and floor, and varying skill levels among equipment users frequently lead to collisions between the shearing machine's rocker arm and the hydraulic support's top beam. This results in equipment damage and asset waste, and seriously endangers the lives of mine workers.

[0003] With the increasing emphasis placed on coal mine production safety by the state and the growing efforts in developing intelligent coal mining, the automation, digitalization, and intelligence of fully mechanized mining equipment have rapidly advanced. Sensors inside coal mining machines and hydraulic supports can monitor data from various devices. However, this data can only clearly reflect the position and attitude of a single piece of equipment and cannot effectively reflect the potential dangerous collision relationship between the two during the mining process. Therefore, research on collision prevention methods is particularly important.

[0004] Currently, some domestic coal mining enterprises and research institutes have conducted extensive research on anti-collision technology between coal mining machines and hydraulic supports. The current technology primarily involves adding sensors to the equipment. However, because the collision location is at the position of the coal mining machine's rocker arm drum and the top beam of the hydraulic support, the working conditions are quite harsh, resulting in a high sensor failure rate and poor data transmission capabilities, failing to achieve a stable and reliable anti-collision alarm. Summary of the Invention

[0005] To address the problems existing in the aforementioned technologies, this invention provides a collision prevention and early warning method for the rocker arm of a coal mining machine and the top beam of a hydraulic support. This method does not require multiple additional sensors; it only uses data provided by the coal mining machine's own height sensor, tilt sensor, and shaft encoder, as well as the hydraulic support's position sensor and height sensor, combined with the data from the centralized control system of the working face, to issue early warning commands to both pieces of equipment, achieving a collision prevention effect. This method has low investment costs, can determine the relative positional relationship between the coal mining machine and the hydraulic support in real time, and effectively warn of potential collisions before they occur. It also boasts high reliability and maintainability.

[0006] To achieve the above objectives, it is necessary to analyze and study the relative positions of the coal mining machine drum, the hydraulic support telescopic mechanism, and the side protection mechanism, as follows: Step 1: Extract and simplify the model from the three-machine matching diagram, and establish a coordinate system: the top plate of the working face is AM, the bottom plate of the working face is BN, and the outer contour cutting boundary line of the coal mining machine drum during horizontal mining is AB; the straight line l is the outer contour cutting boundary line of the coal mining machine drum when the coal mining machine inclination angle is θ, where the coal mining machine inclination angle θ can be measured by the inclination sensor of the coal mining machine; MD is the distance from the support telescopic beam to the outer contour cutting boundary line of the coal mining machine drum, H is the support height, h is the height of the pushing point, and m is the actual beam end distance of the support; then, the functional relationship between MD and the above parameters is obtained through geometric calculation. Step 2: According to the design parameters of the hydraulic support, the beam end distance of the support when the telescopic amount is fully retracted is S0. The cylinder extension length is measured by the telescopic cylinder stroke sensor as d, and the cylinder extension length is measured by the push stroke sensor as D. The actual beam end distance m of the hydraulic support can be represented by the above three parameters. Step 3: The distance between the beam ends of the hydraulic support is one-to-one with the mining height. The difference in mining height has a limited impact on the distance between the beam ends. Taking a mining height of 200mm as a value range, the beam end distance value corresponding to the upper limit value is taken for each mining height range. For example, if the mining height is (A1, A2), the beam end distance value corresponding to A2 is taken. Step 4: When the hydraulic support's side protection mechanism retracts to a position where it does not collide with the coal machine body, the stroke data 'a' is measured by the stroke sensor of the side protection jack. The collision condition is that when the front drum of the coal machine cuts to the current hydraulic support, the side protection mechanism must retract to a position within stroke 'a' to avoid collision. Step 5: When the front drum of the coal mining machine reaches the nth hydraulic support, if any one of the side protection mechanism or telescopic mechanism of the (n+1)th support fails to operate, a warning shutdown will be issued. Step Six: When the front drum of the coal mining machine reaches the nth frame, if the side protection mechanism or telescopic mechanism of the (n+1)th frame is activated, proceed to the next step of the judgment: 1) When the front drum of the coal mining machine reaches the nth frame, the extension / retraction of the support jacks of the (n+1)th frame must satisfy: extension / retraction F < a. 2) When the front drum of the coal mining machine reaches the nth frame, the extension amount of the telescopic jack of the (n+1)th frame must meet the following condition: MD≥r, where r is the preset anti-collision warning distance; Step 7: When all the conditions in Step 6 are met, the working face can operate normally. If any condition is not met, the centralized control system of the working face will control the coal mining machine to stop moving forward, thus achieving the function of preventing collisions. Attached Figure Description

[0007] Figure 1 This is a mathematical model diagram of the anti-collision mechanism of the telescopic mechanism of the present invention; Figure 2 This is a diagram showing the data for the distance between the support beam ends in this invention. Detailed Implementation

[0008] The invention will now be further described with reference to the accompanying drawings.

[0009] like Figure 1 As shown, AM is the position of the top plate of the working face; BN is the position of the bottom plate of the working face; AB is the outer contour boundary line of the coal mining machine drum during horizontal mining; O is the pushing point; M is the end point of the support telescopic beam; the straight line l is the outer contour boundary line of the coal mining machine drum when the coal mining machine is at an overhead mining angle of θ; MD is the distance from the end of the hydraulic support telescopic beam to the coal mining machine drum, which is the target value to be obtained. Based on the coordinate system described above, let the coordinates be as follows: O(L,0);B(0,-h);A(0,Hh);M(m,Hh); The angle of inclination of line l is Its slope k= = = ; The equation of line l is: y = kx + b. It is easy to see that the distance from point O to line l is L. Then: L= We know that b = ( -k)L; Then: MD= ; ; MD=sinθ[km+( -k)L-(Hh)]=mcosθ+(1-cosθ)L-(Hh)sinθ.

[0010] Based on the design parameters of the hydraulic support, the beam end distance of the support when the telescopic extension is fully retracted is S. n The cylinder extension length is measured as d by the telescopic cylinder stroke sensor and as D by the push stroke sensor. These three parameters can be used to represent the actual beam end distance m of the hydraulic support. Therefore, the actual beam end distance m = S n -Dd.

[0011] like Figure 2 As shown, the hydraulic support beam end distance and mining height correspond one-to-one. However, the corresponding parameters for the hydraulic support height and beam end distance are not continuous. Since the mining height difference has a limited impact on the beam end distance, a mining height of 200mm is used as a value interval. The beam end distance value corresponding to the upper limit of each mining height interval is taken. For example, for mining heights (A1, A2), the beam end distance value S2 corresponding to A2 is taken. Therefore, when the hydraulic support height is [A1, A2, A3...A...], the beam end distance is taken as S2. n When the mining height increases sequentially, the beam end distance of the hydraulic support corresponding to each height is [S1, S2, S3...S].n The value is determined by A. n Corresponding to S n .

[0012] The tilt angle θ of the coal mining machine is measured by its own tilt sensor, and the mining height H is measured by its mining height sensor. The values ​​of L and h can be measured using the support design parameters. Therefore, the distance MD from the end of the support telescopic beam to the coal mining machine drum is expressed as: MD = (S n -Dd)cosθ+(1-cosθ)L-(Hh)sinθ.

[0013] When the hydraulic support's side protection mechanism retracts to a position where it does not collide with the coal mining machine body, the stroke data measured by the stroke sensor of the side protection jack is 'a'. The collision condition is that when the front drum of the coal mining machine cuts to the current hydraulic support, the side protection mechanism must retract to a position within the stroke 'a' to avoid collision.

[0014] When the front drum of the coal mining machine reaches the nth hydraulic support, if any one of the side protection mechanism or telescopic mechanism of the (n+1)th support fails to operate, a warning shutdown will be issued.

[0015] When the front drum of the coal mining machine reaches the nth frame, if the side protection mechanism or telescopic mechanism of the (n+1)th frame is activated, then proceed to the next step of the judgment: 1) When the front drum of the coal mining machine reaches the nth frame, the extension / retraction of the support jacks of the (n+1)th frame must satisfy: extension / retraction F < a, 2) When the front drum of the coal mining machine reaches the nth frame, the extension amount of the telescopic jack of the (n+1)th frame must meet the following condition: MD≥r, where r is the preset anti-collision warning distance.

[0016] When all the conditions in step six above are met, the working face can operate normally. If any condition is not met, the working face centralized control system will stop the coal mining machine from advancing, thus achieving the function of preventing collisions.

Claims

1. A method for early warning of collision between a hydraulic support and a coal mining machine, characterized in that, Includes the following steps: Step 1: Extract and simplify the model of the three-machine matching diagram and establish a coordinate system: the top plate of the working face is AM, the bottom plate of the working face is BN, and the outer contour cutting boundary line of the coal mining machine drum during horizontal mining is AB; the straight line l is the outer contour cutting boundary line of the coal mining machine drum when the coal mining machine inclination angle is θ, where the coal mining machine inclination angle θ can be measured by the inclination sensor of the coal mining machine, O is the pushing point; MD is the distance from the support telescopic beam to the outer contour cutting boundary line of the coal mining machine drum, H is the support height, h is the height of the pushing point, L is the distance from the pushing point O to the origin, and m is the actual beam end distance of the support; according to the above coordinate system, set the coordinates as follows: O (L, 0), B (0, -h), A (0, Hh), M (m, Hh), then through geometric calculation, we get MD = mcosθ + (1-cosθ)L - (Hh)sinθ; Step two: Based on the hydraulic support design parameters, the beam end distance of the support when the telescopic stroke is fully retracted is S0. The cylinder extension length measured by the telescopic stroke sensor is d, and the cylinder extension length measured by the push stroke sensor is D. Using these three parameters, the actual beam end distance of the hydraulic support can be expressed as m = S. n -Dd; Step 3: The distance between the hydraulic support beam ends and the mining height are correlated one-to-one. A value interval of 200mm mining height is used, and the beam end distance value corresponding to the upper limit of each mining height interval is taken. As the mining height increases sequentially, the hydraulic support height is [A1, A2, A3...A...]. n The beam end distances of the hydraulic supports at each height are taken as [S1, S2, S3...S]. n The value is determined by A. n Corresponding to S n ; Step 4: When the hydraulic support's side protection mechanism retracts to a position where it does not collide with the coal machine body, the stroke data 'a' is measured by the stroke sensor of the side protection jack. The collision condition is that when the front drum of the coal machine cuts to the current hydraulic support, the side protection mechanism must retract to a position within stroke 'a' to avoid collision. Step 5: When the front drum of the coal mining machine reaches the nth hydraulic support, if any one of the side protection mechanism or telescopic mechanism of the (n+1)th support fails to operate, a warning shutdown will be issued. Step Six: When the front drum of the coal mining machine reaches the nth frame, if the side protection mechanism or telescopic mechanism of the (n+1)th frame is activated, proceed to the next step of the judgment: 1) When the front drum of the coal mining machine reaches the nth frame, the extension / retraction of the support jacks of the (n+1)th frame must satisfy: extension / retraction F < a. 2) When the front drum of the coal mining machine reaches the nth frame, the extension and retraction of the telescopic jack of the (n+1)th frame must satisfy: MD≥r, where r is the preset anti-collision warning distance; Step 7: When all the conditions in Step 6 are met, the working face can operate normally. If any condition is not met, the working face centralized control system will stop the coal mining machine from advancing, thus achieving the function of preventing collisions.

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