A kind of automatic control method and system for coal mining process

Abstract

The present invention provides an automated control method and system for a coal mining process. In the manual coal cutting process, the two paths of geographical location information and geological information are correspondingly linked to the coal cutting parameters, and a coal cutting parameter lookup table is created, so that the subsequent automatic coal cutting process can flexibly select the coal cutting parameters according to the actual travel path and the actual geological parameters, thereby realizing an automated coal cutting process with high safety and high accuracy. In the automatic coal cutting process, the coal cutting results and the execution of the coal cutting parameters are monitored in real time. If there is an abnormality, it is reported immediately or even stopped to ensure the safety of the coal cutting process. The travel path curve can be obtained by an inertial navigation system arranged inside the coal cutting machine to determine whether the coal mining face of the coal cutting machine is a straight line. If it is not a straight line, the coal mining face is adjusted in time to make it perform coal mining operations on the same straight line, thereby preventing the coal mining efficiency from being low due to the bending of the coal mining face and the mutual interference of various coal mining paths.

Description

Technical Field

[0001] The present invention relates to the technical field of coal mine fully mechanized mining, and in particular to an automatic control method and system for a coal mining process. Background Art

[0002] Efficient and intensive coal production is the direction of coal industry development, and the use of advanced mining technology and equipment is the core of efficient and intensive production in mines. The new development situation of the coal industry has put forward higher and newer requirements for coal mine equipment. The intensive production of coal requires coal mine equipment to develop in the direction of complete sets and high reliability. The safe production of coal technology has increased the demand for automated, intelligent and information-based coal mine equipment.

[0003] The realization of automated mining technology with few or no people is a hot topic in the current world mining industry. The technology of the United States and Australia is at the forefront of the world. In the 1980s, they realized the automation of the "three machines" and real-time monitoring of underground environmental safety information. In the early 1990s, Canada began to study remote control mining technology, and Finland also announced a smart mining technology plan. The high-yield and high-efficiency technology of the world's major coal-producing countries has developed rapidly, and the automation technology of the fully mechanized mining face has also emerged. As an important support equipment for the fully mechanized mining face, the degree of automation of the hydraulic support will directly affect the high-yield, high-efficiency and automation degree of the fully mechanized mining face. Summary of the invention

[0004] In order to overcome the above technical defects, the purpose of the present invention is to provide an automated control method and system for coal mining process with high automation, good efficiency and good safety.

[0005] The present invention discloses an automatic control method for a coal mining process, comprising:

[0006] During the manually operated coal mining process, the coal mining machine continuously collects the geographical location information of the coal mining path at intervals of a first preset distance, and stores the externally input cutting parameters corresponding to each geographical location on the coal mining path, and obtains a first cutting parameter extraction table corresponding to the geographical location information and the cutting parameters; it also continuously collects the geological parameters of the coal body to be mined on the coal mining path at intervals of a second preset distance, and stores the externally input cutting parameters corresponding to each position of the coal body to be mined on the coal mining path; it determines which range of several preset geological information ranges the geological parameters are located in, and connects the stored cutting parameters with the preset geological information range to which the geological parameters of the corresponding position of the coal body to be mined belong, and obtains a second cutting parameter extraction table corresponding to the geological parameters and the cutting parameters; during the automatic coal mining process, the coal mining machine selects to extract real-time cutting parameters based on the first cutting parameter extraction table and / or the second cutting parameter extraction table, and performs coal mining and cutting according to the real-time cutting parameters;

[0007] The coal mining machine is arranged on the hydraulic support, and the hydraulic support includes a guide rail and several groups of support frames arranged on the guide rail. The hydraulic support drives the coal mining machine to move on the guide rail and connect with the support frames of different groups through the frame moving action; the hydraulic support also reserves coal mining space for the coal mining machine through the frame retracting action; the hydraulic support is connected to a pump station, and the pump station includes several pump groups, and the number of the pump groups turned on is determined according to the pressure of the hydraulic support; the coal mining machine is provided with a position detection component, and each of the support frames is provided with a position receiving component that is communicatively connected to the position detection component; each of the support frames is also provided with a controller, and the controller is connected to the position receiving component. When the position receiving component on the support frame receives the position signal of the position detection component, the controller controls the support frame to retract the frame;

[0008] The three-dimensional position data of the coal mining machine during the coal mining process is obtained by an inertial navigation module arranged on the coal mining machine, and the three-dimensional position data includes latitude and longitude information and altitude information; a coal mining work trajectory curve of the coal mining machine is drawn according to the three-dimensional position data; during the coal mining process of the coal mining machine, at intervals of a first preset time, it is continuously determined whether the straightness of the coal mining work trajectory curve is less than a preset straightness threshold value; if not, the coal mining face of the coal mining machine is controlled to move a preset distance in a first direction, a second direction, a third direction or a fourth direction; the first direction, the second direction, the third direction and the fourth direction are perpendicular to the forward direction of the coal mining machine, and the first direction is opposite to the second direction, and the third direction is opposite to the fourth direction.

[0009] Preferably, it also includes a central control integrator, which is connected to the controller on each of the support frames and independently controls each of the controllers; the coal mining machine, each of the support frames and the central control integrator are provided with communication modules, and the communication modules communicate with each other through a 5G network or wireless WIFI.

[0010] Preferably, the central control integrator includes a first central control integrator located on the ground and a second central control integrator located in a coal mining shaft; when the controller receives the control signal of the first central control integrator, it stops receiving the control signal of the second central control integrator; when the controller receives the control signal of the second central control integrator, it stops receiving the control signal of the first central control integrator.

[0011] Preferably, a position detection component is provided on the shearer, and a position receiving component communicatively connected to the position detection component is provided on each support frame; a controller is further provided on each support frame, and the controller is connected to the position receiving component. When the position receiving component on the support frame receives the position signal from the position detection component, the controller controls the support frame to perform the action of retracting the support frame, including:

[0012] The position detection component is an infrared emission component, and the position receiving component is an infrared receiving component; the infrared signal emission range of the infrared emission component is S1, and the distance between two adjacent support frames is S2, where S2 < S1 < 2S2; the displacement speed V of the current shearer is obtained through the time difference of infrared signal reception between two adjacent support frames; when the displacement speed V is less than the first preset speed, the support frame of the next group of the currently supported support frame performs the action of retracting the support frame; when the displacement speed V is greater than the first preset speed and less than the second preset speed, the support frames of the next two groups of the currently supported support frame perform the action of retracting the support frame; when the displacement speed V is greater than the second preset speed, the support frames of the next three groups of the currently supported support frame perform the action of retracting the support frame; the first preset speed is half of the speed required for the shearer to pass between two adjacent support frames in one minute, and the second preset speed is the speed required for the shearer to pass between two adjacent support frames in one minute;

[0013] Or the position detection component is a shaft encoder for obtaining the displacement distance S3 of the current position of the shearer from the starting base point, and the position receiving component is a coded data receiver; the difference between the displacement distance S3 received by the encoder data receiver and the distance of the support frame corresponding to the encoder from the starting base point is S4; the distance between two adjacent support frames is S2; when S2 < S4 < 2S2, the support frame corresponding to the encoder performs the action of retracting the support frame.

[0014] Preferably, the shearer is provided on a hydraulic support, and the hydraulic support drives the shearer to move through the telescopic frame action; controlling the shearer to move the coal mining face in the first direction or the second direction or the third direction or the fourth direction includes: controlling the hydraulic support to perform the telescopic frame action so that the coal mining face of the shearer moves a preset distance in the first direction or the second direction or the third direction or the fourth direction.

[0015] Preferably, during the coal mining process of the shearer, at intervals of the first preset time, continuously judge whether the straightness of the coal mining working trajectory curve is less than the preset straightness threshold. If not, controlling the coal mining face of the shearer to move a preset distance in the first direction or the second direction or the third direction or the fourth direction further includes:

[0016] While controlling the coal mining face of the coal mining machine to move in a first direction, a second direction, a third direction, or a fourth direction, reduce the moving speed of the coal mining machine in the forward direction; accumulate the number of times C that the coal mining face of the coal mining machine is controlled to move in the first direction, the second direction, the third direction, or the fourth direction; when C is greater than a preset number of times, issue a coal mining machine fault prompt message or request geological exploration.

[0017] Preferably, the position detection component is a shaft encoder, the position receiving component is a coded data receiver, and the coal mining machine is also provided with an infrared emitting component, and each group of support frames is also provided with an infrared receiving component; the displacement speed V of the current coal mining machine is obtained by the time difference of receiving the infrared signal between two adjacent support frames;

[0018] When the displacement speed V is less than the first preset speed, the rear group of support frames of the currently supported support frames will perform the frame retracting action; when the displacement speed V is greater than the first preset speed and less than the second preset speed, the rear two groups of support frames of the currently supported support frames will perform the frame retracting action; when the displacement speed V is greater than the second preset speed, the rear three groups of support frames of the currently supported support frames will perform the frame retracting action; the first preset speed is half of the speed required for the coal mining machine to pass between two adjacent support frames in one minute, and the second preset speed is the speed required for the coal mining machine to pass between two adjacent support frames in one minute.

[0019] Preferably, during the automatic coal mining process, the coal mining machine selects to extract real-time cutting parameters according to the first cutting parameter extraction table and / or the second cutting parameter extraction table, and performs coal mining and cutting according to the real-time cutting parameters, and further includes:

[0020] During the automatic coal mining process, the coal mining machine again selects to extract real-time cutting parameters based on the first cutting parameter extraction table and / or the second cutting parameter extraction table after a coal cutting cycle is completed, and performs coal mining and cutting according to the real-time cutting parameters; the coal cutting cycle is the coal cutting process in which the coal mining machine advances the first preset distance or the second preset distance.

[0021] Preferably, the determination of whether each item of actual cutting information is within the cutting parameter range includes: if the first cutting parameter extraction table is currently being extracted, then determining whether each item of actual cutting information is respectively within the first cutting parameter range corresponding to the current geographic location information; the first cutting parameter range is the range of error values ​​of plus or minus 5 percent of the cutting parameter corresponding to the geographic location information in the first cutting parameter extraction table; if the second cutting parameter extraction table is currently being extracted, then determining whether each item of actual cutting information is respectively within the second cutting parameter range corresponding to the current geological parameter; the second cutting parameter range is the range of error values ​​of plus or minus 10 percent of the cutting parameter corresponding to the preset geological information range to which the geological parameter in the second cutting parameter extraction table belongs.

[0022] The present invention also discloses an automatic control system for a coal mining process, wherein the coal mining machine is provided with an inertial navigation module, and the central control integrator is connected to the coal mining machine and the inertial navigation module; the central control integrator obtains the positioning and navigation data of the inertial navigation module, thereby obtaining the three-dimensional position data of the coal mining machine during the coal mining process;

[0023] The central control integrator comprises a processing module. When the coal mining machine is manually operated and moves forward in coal mining, the processing module continuously obtains geographical location information of the coal mining path through the inertial navigation module at intervals of a first preset distance; the processing module stores externally input cutting parameters corresponding to each geographical location on the coal mining path, and processes and obtains a first cutting parameter extraction table corresponding to the geographical location information and the cutting parameters;

[0024] The central control integrator includes a geological exploration module. During the manual operation of the coal mining machine, the processing module controls the geological exploration module to continuously collect geological parameters of the coal body to be mined on the coal mining path at intervals of a second preset distance; the processing module stores externally input cutting parameters corresponding to each position of the coal body to be mined on the coal mining path, determines which range of several preset geological information ranges the geological parameters are located in, and connects the stored cutting parameters with the preset geological information range to which the geological parameters of the corresponding position of the coal body to be mined belong, so as to obtain a second cutting parameter extraction table corresponding to the geological parameters and the cutting parameters;

[0025] When the coal mining machine is in the process of automatically mining coal, the processing module extracts real-time cutting parameters according to the first cutting parameter extraction table and / or the second cutting parameter extraction table, and controls the coal mining machine to mine and cut coal according to the real-time cutting parameters;

[0026] The coal mining machine is arranged on the hydraulic support, and the hydraulic support includes several groups of support frames. The hydraulic support drives the coal mining machine to move through the frame moving action to connect with the support frames of different groups; the hydraulic support also reserves coal mining space for the coal mining machine through the frame retracting action; the coal mining machine is provided with a position detection component, and each of the support frames is provided with a position receiving component that is communicatively connected with the position detection component; each of the support frames is also provided with a controller, and the controller is connected with the position receiving component. When the position receiving component on the support frame receives the position signal of the position detection component, the controller controls the support frame to retract the frame;

[0027] The hydraulic support is connected to a pump station, and the pump station includes a plurality of pump groups, and the number of the pump groups to be turned on is determined according to the pressure of the hydraulic support;

[0028] Each of the support frames is provided with an inclination detector for detecting the inclination of the support frame; the central control integrator includes an alarm module; when the angle detected by the inclination detector exceeds a preset inclination threshold range, the controller on the support frame controls the support frame to stop dynamic movement and sends an alarm signal to the alarm module of the central control integrator;

[0029] The support frame is also provided with a camera, which is arranged on a pan-tilt platform; the angle of the pan-tilt platform is adjusted so that the camera can capture images of various positions and angles of the support frame; the camera is connected to the central control integrator; the central control integrator controls the rotation of the pan-tilt platform, and sends the images captured by the camera to the central control integrator through the communication module;

[0030] The central control integrator draws a coal mining working trajectory curve of the coal mining machine according to the three-dimensional position data; during the coal mining operation of the coal mining machine, the central control integrator continuously determines whether the straightness of the coal mining working trajectory curve is less than a preset straightness threshold at intervals of a first preset time; if not, the coal mining face of the coal mining machine is controlled to move a preset distance in a first direction, a second direction, a third direction, or a fourth direction and at the same time reduce the moving speed of the coal mining machine in the forward direction; the first direction, the second direction, the third direction, and the fourth direction are perpendicular to the forward direction of the coal mining machine, and the first direction is opposite to the second direction, and the third direction is opposite to the fourth direction;

[0031] The central control integrator accumulates the number of times C that the coal mining face of the coal mining machine is controlled to move in the first direction, the second direction, the third direction or the fourth direction; when C is greater than the preset number of times, a coal mining machine fault prompt message is issued or a geological survey is requested.

[0032] Compared with the prior art, the above technical solution has the following beneficial effects:

[0033] 1. In the process of manual coal cutting, the geographical location information and geological information are used to correspond to the coal cutting parameters, and a coal cutting parameter lookup table is created, so that the subsequent automatic coal cutting process can flexibly select the coal cutting parameters according to the actual path and actual geological parameters, thereby realizing an automated coal cutting process with high safety and accuracy. In the process of automatic coal cutting, the coal cutting results and the execution of coal cutting parameters are monitored in real time. If there is an abnormality, it is reported immediately or even stopped to ensure the safety of the coal cutting process.

[0034] 2. The inertial navigation system installed inside the coal mining machine can monitor the travel path of the coal mining machine to obtain the travel path curve. According to the straightness of the curve, it is judged whether the coal mining face of the coal mining machine is a straight line. If it is not a straight line, the coal mining face is adjusted in time to make it mine coal on the same straight line, so as to prevent the coal mining efficiency from being low due to the bending of the coal mining face and the interference between the various coal mining paths;

[0035] 3. Each support frame is controlled individually and they communicate with each other through the network to transmit information. When the coal mining machine is running, the frames are promptly retracted according to the position of the coal mining machine to reserve coal mining space for the coal mining machine. The running speed of the coal mining machine is used to determine whether one support frame or multiple support frames are to be retracted. When the running speed of the coal mining machine is too fast, in order to prevent the coal mining machine from running to this point and not being able to retract the frames in time, multiple support frames are required to be retracted, which is safer. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] Figure 1 A flow chart of the memory cutting process of coal mining parameters provided by the present invention;

[0037] Figure 2 Another flow chart of the memory cutting process of coal mining parameters provided by the present invention;

[0038] Figure 3 A flow chart of the automatic following process of the hydraulic support provided by the present invention;

[0039] Figure 4 A flow chart of the automatic straightening process of a coal mining face provided by the present invention. DETAILED DESCRIPTION

[0040] The advantages of the present invention are further described below in conjunction with the accompanying drawings and specific embodiments.

[0041] Exemplary embodiments will be described in detail herein, examples of which are shown in the accompanying drawings. When the following description refers to the drawings, the same numbers in different drawings represent the same or similar elements unless otherwise indicated. The embodiments described in the following exemplary embodiments do not represent all embodiments consistent with the present disclosure. Instead, they are merely examples of devices and methods consistent with some aspects of the present disclosure as detailed in the appended claims.

[0042] The terms used in this disclosure are for the purpose of describing specific embodiments only and are not intended to limit the disclosure. The singular forms of "a", "said" and "the" used in this disclosure and the appended claims are also intended to include plural forms unless the context clearly indicates otherwise. It should also be understood that the term "and / or" used herein refers to and includes any or all possible combinations of one or more associated listed items.

[0043] It should be understood that although the terms first, second, third, etc. may be used in the present disclosure to describe various information, such information should not be limited to these terms. These terms are only used to distinguish the same type of information from each other. For example, without departing from the scope of the present disclosure, the first information may also be referred to as the second information, and similarly, the second information may also be referred to as the first information. Depending on the context, the word "if" as used herein may be interpreted as "at the time of" or "when" or "in response to determining".

[0044] In the description of the present invention, it is necessary to understand that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the accompanying drawings, and are 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 operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0045] In the description of the present invention, unless otherwise specified and limited, it should be noted that the terms "installation", "connection" and "connection" should be understood in a broad sense. For example, it can be a mechanical connection or an electrical connection, or it can be the internal connection of two components. It can be a direct connection or an indirect connection through an intermediate medium. For ordinary technicians in this field, the specific meanings of the above terms can be understood according to the specific circumstances.

[0046] In the following description, the suffixes such as "module", "component" or "unit" used to represent elements are only used to facilitate the description of the present invention, and have no specific meanings. Therefore, "module" and "component" can be used interchangeably.

[0047] The automated control method for coal mining process of the present invention mainly includes the automatic following process of hydraulic supports, the automatic straightening process of coal mining face and the memory cutting process of coal mining parameters, and the automation of the entire coal mining work is realized by highly automating these three directions.

[0048] See attached Figure 1 The memory cutting process of coal mining parameters first stores various coal cutting parameters in the manual coal cutting process, and then extracts the parameters for automatic coal cutting in the next automatic coal cutting process. The specific steps include:

[0049] During the manual operation of the coal mining machine, the coal mining machine continuously collects the geographical location information of the coal mining path at intervals of a first preset distance, stores the externally input cutting parameters corresponding to each geographical location on the coal mining path, and obtains a first cutting parameter extraction table corresponding to the geographical location information and the cutting parameters;

[0050] During the manual operation of the coal mining process, the coal mining machine continuously collects the geological parameters of the coal body to be mined on the coal mining path at intervals of a second preset distance, and stores the externally input cutting parameters corresponding to each position of the coal body to be mined on the coal mining path; determines which range of several preset geological information ranges the geological parameters are located in, and connects the stored cutting parameters with the preset geological information range to which the geological parameters of the corresponding position of the coal body to be mined belong, and obtains a second cutting parameter extraction table corresponding to the geological parameters and the cutting parameters;

[0051] During the automatic coal mining process, the coal mining machine selects to extract real-time cutting parameters based on the first cutting parameter extraction table and / or the second cutting parameter extraction table, and performs coal mining and cutting according to the real-time cutting parameters.

[0052] During the automatic coal mining process, the coal mining machine selects to extract the real-time cutting parameters according to the first cutting parameter extraction table and / or the second cutting parameter extraction table again after a coal cutting cycle is completed, and performs coal mining and cutting according to the real-time cutting parameters. A coal cutting cycle is the coal cutting process of the coal mining machine advancing the first preset distance or the second preset distance. That is, if the first cutting parameter extraction table is extracted in the previous cycle, the previous cycle is the coal cutting process of the first preset distance. When the coal cutting process of this cycle is completed, you can choose to continue to extract the first cutting parameter extraction table, or you can use the second cutting parameter extraction table instead.

[0053] Coal cutting parameters include but are not limited to cutting height, speed, power (expressed as voltage and current), drum inclination angle of the coal mining machine, etc.

[0054] Geological information parameters include but are not limited to moisture, hardness, chemical elements, etc. of coal seams.

[0055] For better, see the attached Figure 2 In order to ensure the safety of the coal cutting process, it is necessary to monitor the coal cutting process. If any abnormality occurs, it should be reported in time, warning information should be issued, or even the cutting operation should be stopped. That is, during the automatic coal mining process, the coal mining machine continuously detects the coal mining result information and determines whether the coal mining result information is within the preset coal mining information threshold range. If not, it uploads the coal mining abnormality prompt information and records the current geographical location information and geological parameters, as well as the actual cutting parameters used.

[0056] Preferably, the coal mining result information includes the actual amount of coal mined, and whether the coal cutting process is normal is judged based on the actual amount of coal obtained by cutting the coal.

[0057] Preferably, in addition to judging the abnormality of the coal cutting process based on the coal cutting results, it can also be judged based on the execution of the coal cutting parameters, that is, judging whether the actual cutting information is within the cutting parameter range. If not, upload the coal mining abnormality prompt information and record the current geographical location information, geological parameters, and the actual cutting parameters used, and stop the cutting operation. In addition, you can choose to extract the first cutting parameter extraction table or the second cutting parameter extraction table in the next coal cutting cycle.

[0058] Specific:

[0059] If the first cutting parameter extraction table is currently extracted, it is determined whether each item of actual cutting information is respectively within the first cutting parameter range corresponding to the current geographic location information. The first cutting parameter range is the range of the error value of plus or minus 5% of the cutting parameter corresponding to the geographic location information in the first cutting parameter extraction table. For example, if the cutting height parameter corresponding to the current geographic location information is 3m, then the first cutting height range is 3.15-2.85m.

[0060] It should be noted that the error value of plus or minus 5% is not the error range limited to the implementation of the present invention. In actual processes, other error value ranges may also be used.

[0061] If the second cutting parameter extraction table is currently extracted, it is determined whether each actual cutting information is respectively within the second cutting parameter range corresponding to the current geological parameter. The second cutting parameter range is the range of the error value of plus or minus 10% of the cutting parameter corresponding to the preset geological information range to which the geological parameter in the second cutting parameter extraction table belongs.

[0062] Likewise, the error value of plus or minus 10% is not a limited error range for implementing the present invention, and other error value ranges may also be used in actual processes.

[0063] Preferably, in order to ensure that the second cutting parameter extraction table can adapt to complex coal mining geological terrain, the preset geological information range should be as large as possible, and usually, at least 5 preset geological information ranges should be included. A variety of choices make the final parameters more in line with the actual situation.

[0064] Preferably, the preset geological information range can be set according to the upper and lower thresholds of each geological parameter, that is, the preset geological information range is set in sequence strictly according to the upper and lower thresholds of each parameter, and multiple parameters do not affect each other.

[0065] In addition, each parameter of the geological parameters can be combined by an algorithm to obtain a preset geological information range. That is, each parameter is combined and analyzed by an algorithm to obtain a preset geological information range.

[0066] The automatic following process of the hydraulic support is based on the automatic following system. The automatic following system mainly includes a coal mining machine, a transportation component and a support component. The support component mainly plays the role of supporting the working face and can effectively prevent the working face from collapsing. The support component mainly includes a hydraulic support. The hydraulic support is powered by high-pressure liquid and is composed of a number of hydraulic components (cylinders and valves) and some metal structural parts in a certain connection method. It is a kind of coal mining working face equipment that supports and controls the roof. The hydraulic support is used to effectively and reliably support and control the working face roof, and can also move forward and advance the conveying component of the working face. It is used in conjunction with the coal mining machine and the conveying component. The hydraulic support has the advantages of high structural strength, good support performance, fast frame moving speed, safety and reliability, etc. It can enable the coal mining working face to achieve high output, high efficiency and high recovery rate, reduce labor intensity, reduce costs and improve tunneling productivity, and achieve safe production.

[0067] The hydraulic support relies on high-pressure liquid, columns and corresponding power jacks to achieve four basic actions: lifting, retracting, pushing and moving. For lifting, the operating valve is placed in the "lifting" position, and the high-pressure liquid delivered by the pump station through the pressure hose enters the lower cavity of the column through the hydraulic control one-way valve; the liquid in the upper cavity of the column flows to the return pipe through the control valve, so the column extends outward and the support rises; for pushing, when the support is in the supporting state, the control valve is placed in the "pushing" position, and the high-pressure liquid enters the left cavity of the push jack through the control valve; the liquid in its right cavity flows to the return pipe through the control valve. At this time, the piston rod of the push jack extends to push the working face conveyor toward the coal wall. The pushing distance is generally one cutting depth of the coal mining machine; when the frame is retracted, the control valve is turned to the "retracted" position, and the high-pressure liquid flows into the upper cavity of the column through the control valve, and the hydraulic control one-way valve is opened at the same time; the liquid in the lower cavity of the column flows to the return pipe after the hydraulic control one-way valve and the control valve, so the column retracts and the height of the support is reduced; when the frame is moved, after the support is unloaded (retracted) or partially unloaded, the control valve is turned to the "moving" position, and the high-pressure liquid enters the right cavity of the push jack; the low-pressure liquid in the left cavity of the jack flows back to the return pipeline, and the jack cylinder drives the support to move right. Generally, the moving distance is equal to the pushing distance.

[0068] The coal mining machine is arranged on a hydraulic support, which includes a guide rail and several groups of support frames arranged on the guide rail. The hydraulic support drives the coal mining machine to move on the guide rail and connect with different groups of support frames through the frame moving action; the hydraulic support also reserves coal mining space for the coal mining machine through the frame retracting action. Specifically, the hydraulic support is required to support the coal mining machine before and after coal mining. When the coal mining machine is mining coal, the support frame currently connected to the coal mining machine needs to be retracted to reserve coal mining space for the coal mining machine. Even the support frame to be connected in the next process also needs to be retracted as a preparatory action to prevent the coal mining machine from running to this point and not being able to retract the frame in time.

[0069] Specifically, the coal mining machine 1 is arranged on a scraper, and the scraper moves on a hydraulic support, thereby driving the coal mining machine 1 to move.

[0070] The hydraulic support is connected to a pump station, which includes several pump groups. The number of pump groups to be turned on is determined according to the pressure of the hydraulic support.

[0071] A position detection component is provided on the coal mining machine, and a position receiving component is provided on each support frame, which is communicatively connected to the position detection component. The support frame senses the position state of the coal mining machine through the communication between the position detection component and the position receiving component. The present invention provides two implementation methods of the position detection component and the position receiving component, one is an infrared detection device, and the other is a shaft encoder.

[0072] Each support frame is provided with a controller, which is connected to a position receiving component. When the position receiving component on the support frame receives a position signal from a position detection component, the controller controls the support frame to retract. Each support frame is controlled individually, resulting in less mutual interference, a lower error rate, and greater safety.

[0073] It also includes a central control integrator, which is connected to the controller on each support frame and the coal mining machine to control the coal mining machine and each controller. The coal mining machine, each support frame and the central control integrator are provided with communication modules, and each communication module communicates with each other through a 5G network or wireless WIFI.

[0074] The controller 4 is an execution controller, which independently controls the action of one support frame 2. Usually, the controller 4 is connected to the electro-hydraulic control module of the central control integrator, and the central control integrator controls each controller 4 through the electro-hydraulic control module.

[0075] Preferably, when the shaft encoder is used as the position detection component and the coded data receiver is used as the position receiving component, the coal mining machine is also provided with an infrared emitting component, and each support frame is also provided with an infrared receiving component. When used in conjunction with the shaft encoder, the position judgment is more accurate than that of a single infrared detection device.

[0076] Preferably, in order to monitor the inclination angle of each support part of the support frame and ensure the support safety, each support frame is also provided with an inclination detector for detecting the inclination angle of the support frame. The central control integrator includes an alarm module. When the angle detected by the inclination detector exceeds the preset inclination threshold range, the controller on the support frame controls the support frame to stop dynamic movement and sends an alarm signal to the alarm module of the central control integrator to remind the personnel to pay attention.

[0077] Preferably, the central control integrator includes a first central control integrator and a second central control integrator, the first central control integrator is arranged on the ground, and the second central control integrator is arranged in the coal mining shaft, and more preferably in the coal mining machine, and control can be realized both underground and above the shaft. In order to ensure control safety, when the controller receives the control signal of the first central control integrator, it stops receiving the control signal of the second central control integrator; when the controller receives the control signal of the second central control integrator, it stops receiving the control signal of the first central control integrator, that is, each controller is only controlled by one central control integrator, and cannot be controlled by two central control integrators at the same time.

[0078] Preferably, a camera is also provided on the support frame. The camera is installed on the pan-tilt head. By adjusting the angle of the pan-tilt head, the camera can capture images of various positions and angles of the support frame, realizing real-time video monitoring of the support frame. The camera is connected to the central control integrator. The central control integrator controls the rotation of the pan-tilt head and sends the images captured by the camera to the central control integrator through the communication module for the operator to view. Usually, one camera is set for every six support frames.

[0079] See the appendix Figure 3 , an infrared emission component can be used as the position detection component, and an infrared reception component can be used as the position reception component. The infrared signal emission range of the infrared emission component is S1, and the distance between two adjacent support frames is S2. It can be set that S2 < S1 < 2S2.

[0080] The displacement speed V of the current shearer is obtained through the time difference of the infrared signal reception between two adjacent support frames. When the displacement speed V is less than the first preset speed, the rear set of support frames of the currently supported support frame performs the retraction action; when the displacement speed V is greater than the first preset speed and less than the second preset speed, the rear two sets of support frames of the currently supported support frame perform the retraction action; when the displacement speed V is greater than the second preset speed, the rear three sets of support frames of the currently supported support frame perform the retraction action. The first preset speed is half of the speed required for the shearer to pass between two adjacent support frames in one minute, and the second preset speed is the speed required for the shearer to pass between two adjacent support frames in one minute. According to the running speed of the shearer, it is judged whether one support frame or multiple support frames perform the retraction action. When the running speed of the shearer is too fast, in order to prevent the shearer from not having enough time to retract the support frames in time when it runs to this position, multiple support frames need to perform the retraction action, which is safer.

[0081] An axle encoder can also be used as the position detection component to obtain the displacement distance S3 of the current position of the shearer from the starting base point, and a coded data receiver is used as the position reception component. The difference between the displacement distance S3 received by the encoder data receiver and the distance of the support frame corresponding to this encoder from the starting base point is S4, and the distance between two adjacent support frames is S2. When S2 < S4 < 2S2, the support frame corresponding to this encoder performs the retraction action, that is, when the shearer runs to the position of the previous support frame, the retraction action is performed.

[0082] More preferably, when an axle encoder is used as the position detection component and a coded data receiver is used as the position reception component, an infrared emission component is also provided on the shearer, and an infrared reception component is also provided on each group of support frames.

[0083] Specifically, similar to the above-mentioned infrared detection, the displacement speed V of the current coal mining machine is obtained by the time difference of infrared signal reception between two adjacent support frames: when the displacement speed V is less than the first preset speed, the rear group of support frames of the currently supported support frames will perform a frame retraction action; when the displacement speed V is greater than the first preset speed and less than the second preset speed, the rear two groups of support frames of the currently supported support frames will perform a frame retraction action; when the displacement speed V is greater than the second preset speed, the rear three groups of support frames of the currently supported support frames will perform a frame retraction action.

[0084] The first preset speed is half of the speed required for the coal mining machine to pass between two adjacent support frames in one minute, and the second preset speed is the speed required for the coal mining machine to pass between two adjacent support frames in one minute.

[0085] That is, the running speed of the coal mining machine is used to determine whether one support frame or multiple support frames are to be retracted. When used in conjunction with the shaft encoder, the position judgment is more accurate than that of a single infrared detection device.

[0086] See attached Figure 4 The automatic straightening process of the coal mining face includes the following steps:

[0087] The three-dimensional position data of the coal mining machine during the coal mining process is obtained through the inertial navigation system installed on the coal mining machine;

[0088] Draw the coal mining working trajectory curve of the coal mining machine according to the three-dimensional position data;

[0089] During the coal mining process of the coal mining machine, at intervals of a first preset time, it is continuously determined whether the straightness of the coal mining work trajectory curve is less than a preset straightness threshold. If not, the coal mining face of the coal mining machine is controlled to move a preset distance in the first direction, the second direction, the third direction, or the fourth direction.

[0090] The first direction, the second direction, the third direction, and the fourth direction are perpendicular to the forward direction of the coal mining machine, and the first direction is opposite to the second direction, and the third direction is opposite to the fourth direction. It can be understood that the first direction and the second direction are the left and right directions of the coal mining machine, respectively, and the third direction and the fourth direction are the up and down directions of the coal mining machine, respectively. That is, the coal mining machine is controlled to maintain a straight line in the left and right directions, and the coal mining machine is controlled to maintain a straight line in the up and down directions. Of course, the first direction and the second direction can also be the up and down directions of the coal mining machine, respectively, and the third direction and the fourth direction can be the left and right directions of the coal mining machine, respectively.

[0091] The present invention can obtain the three-dimensional position data of the coal mining machine in real time through the inertial navigation system, and the movement trajectory curve of the coal mining machine in the coal mining work can be drawn on the coordinate system based on the three-dimensional position data. According to the curve, it can be intuitively judged whether the movement of the coal mining machine in the coal mining work is a straight line, thereby judging whether the coal mining working face is a straight line. Compared with the prior art of judging whether the coal mining working face is a straight line through sensors, etc., the present invention judges through the curve drawn by measured data, which is more accurate and reliable, and makes the operator and monitoring personnel more visually intuitive about the travel of the coal mining machine, and has a strong warning effect.

[0092] Specifically, the central control integrator includes a curve drawing component, and the central control integrator draws the three-dimensional position data into a coal mining work trajectory curve through the curve drawing component.

[0093] Preferably, the coal mining machine is arranged on a hydraulic support, and the hydraulic support drives the coal mining machine to move through the telescopic frame action. The telescopic frame action includes left and right telescopic movement to drive the coal mining machine to move left and right, and also includes up and down telescopic movement to drive the coal mining machine to move up and down, thereby controlling the upper, lower, left and right positions of the coal mining face.

[0094] By controlling the hydraulic support to execute the telescopic frame action, the coal mining face of the coal mining machine moves a preset distance in the first direction, the second direction, the third direction, or the fourth direction.

[0095] It should be noted that the preset distance can be a fixed distance, or an automatic distance calculated by the algorithm after measuring the relevant parameters of the curve. If it is a fixed distance, it may not be in place in one move, and it is necessary to wait for the next straightness judgment before moving again until the straightness is less than the preset straightness threshold. If it is an automatic distance, it can be in place in one step, but it needs to rely on an algorithm, and the algorithm needs to be calibrated regularly to ensure the accuracy of the algorithm.

[0096] Preferably, when the adjustment distance is the moving distance, after one adjustment, stop obtaining the curvature of the current coal mining work trajectory curve, and instead obtain the curvature of the coal mining work trajectory curve between the starting position and the current position to determine whether the straightness of the coal mining work trajectory curve is less than a preset straightness threshold. If not, continue to control the coal mining face of the coal mining machine to move a first preset distance in the first direction, the second direction, the third direction, or the fourth direction until the straightness of the coal mining work trajectory curve between the starting position and the current position is less than the preset straightness threshold.

[0097] In addition, it can also be set for manual input by operators.

[0098] Preferably, the three-dimensional location data includes latitude and longitude information and altitude information, and the three-dimensional geographic location data of the coal mining machine can be intuitively obtained based on the information, which is not affected by the depth of the underground coal mining well.

[0099] Preferably, due to failures such as coal mining machine failure and hydraulic support failure, the coal mining face of the coal mining machine may not be able to work in the same straight line, or when there are geological anomalies and interferences, the coal mining face may not be able to work in the same straight line.

[0100] Therefore, it is necessary to continuously judge whether the straightness of the coal mining work trajectory curve is less than the preset straightness threshold at intervals of the first preset time during the coal mining process of the coal mining machine. If not, the coal mining face of the coal mining machine is controlled to move a preset distance in the first direction, the second direction, the third direction or the fourth direction, and the number of times C that the coal mining face of the coal mining machine is controlled to move in the first direction, the second direction, the third direction or the fourth direction is accumulated. When C is greater than the preset number of times, a coal mining machine fault prompt message is issued or a geological survey is requested.

[0101] That is, when the coal mining face of the coal mining machine continues to adjust its position for multiple times, prompts and warnings are issued to the operator to make equipment judgments or geological judgments.

[0102] In addition, a more accurate judgment can be set, that is, judgment is made within a time period. Given a preset time period, if the number of adjustments C of the coal mining machine within the preset time period is greater than the preset number, a coal mining machine fault prompt message or a request for geological exploration is issued. However, if this judgment method is adopted, more invalid prompts may be caused, that is, the prompt message is normal and does not correspond to a fault or geological abnormality.

[0103] Specifically, the central control integrator also includes a counting component, which accumulates the number of times C that the coal mining face of the coal mining machine moves toward the first direction, the second direction, the third direction, or the fourth direction.

[0104] Preferably, in one case, coal mining is stopped when the position of the coal mining face is adjusted, and coal mining will not be resumed until the coal mining face returns to a normal position. In another case, coal mining is carried out simultaneously with the position of the coal mining face being adjusted. If the normal coal mining speed is maintained at this time, errors in the adjustment accuracy may result. Therefore, while controlling the coal mining face of the coal mining machine to move in the first direction, the second direction, the third direction or the fourth direction, the moving speed of the coal mining machine in the forward direction is reduced, and the normal speed is restored after the adjustment is completed.

[0105] The present invention also provides an automated control system for the coal mining process, wherein an inertial navigation module is provided on the coal mining machine, and a central control integrator is connected to the coal mining machine and the inertial navigation module; the central control integrator obtains the positioning and navigation data of the inertial navigation module, thereby obtaining the three-dimensional position data of the coal mining machine during the coal mining process.

[0106] The central control integrator includes a processing module. During the manually operated coal mining process of the coal mining machine, the processing module continuously obtains the geographical location information of the coal mining path at intervals of a first preset distance through the inertial navigation module; the processing module stores the externally input cutting parameters corresponding to each geographical location on the coal mining path, and processes and obtains the first cutting parameter extraction table corresponding to the geographical location information and the cutting parameters.

[0107] The central control integrator includes a geological exploration module. During the manually operated coal mining process of the coal mining machine, the processing module controls the geological exploration module to continuously collect the geological parameters of the coal body to be mined on the coal mining path at intervals of a second preset distance; the processing module stores the externally input cutting parameters corresponding to each position of the coal body to be mined on the coal mining path, determines which range of several preset geological information ranges the geological parameters are located in, and connects the stored cutting parameters with the preset geological information range to which the geological parameters of the corresponding position of the coal body to be mined belong, so as to obtain a second cutting parameter extraction table corresponding to the geological parameters and the cutting parameters.

[0108] During the automatic coal mining process of the coal mining machine, the processing module extracts real-time cutting parameters based on the first cutting parameter extraction table and / or the second cutting parameter extraction table, and controls the coal mining machine to perform coal mining and cutting according to the real-time cutting parameters.

[0109] The coal mining machine is arranged on a hydraulic support, which includes several groups of support frames. The hydraulic support drives the coal mining machine to move through the frame moving action to connect with different groups of support frames; the hydraulic support also reserves coal mining space for the coal mining machine through the frame retracting action; the coal mining machine is provided with a position detection component, and each support frame is provided with a position receiving component which is communicatively connected to the position detection component; each support frame is also provided with a controller, which is connected to the position receiving component. When the position receiving component on the support frame receives the position signal of the position detection component, the controller controls the support frame to perform the frame retracting action.

[0110] The hydraulic support is connected to a pump station, which includes several pump groups. The number of pump groups to be turned on is determined according to the pressure of the hydraulic support.

[0111] Each support frame is provided with an inclination detector for detecting the inclination of the support frame; the central control integrator includes an alarm module; when the angle detected by the inclination detector exceeds the preset inclination threshold range, the controller on the support frame controls the support frame to stop dynamic movement and sends an alarm signal to the alarm module of the central control integrator.

[0112] The support frame is also provided with a camera, which is arranged on the gimbal; the angle of the gimbal is adjusted so that the camera can capture images of various positions and angles of the support frame; the camera is connected to the central control integrator; the central control integrator controls the rotation of the gimbal, and sends the images captured by the camera to the central control integrator through the communication module.

[0113] The central control integrator draws the coal mining working trajectory curve of the coal mining machine according to the three-dimensional position data; during the coal mining operation of the coal mining machine, the central control integrator continuously determines whether the straightness of the coal mining working trajectory curve is less than a preset straightness threshold at intervals of a first preset time; if not, the coal mining face of the coal mining machine is controlled to move a preset distance in the first direction, the second direction, the third direction or the fourth direction and at the same time reduce the moving speed of the coal mining machine in the forward direction; the first direction, the second direction, the third direction and the fourth direction are perpendicular to the forward direction of the coal mining machine, and the first direction is opposite to the second direction, and the third direction is opposite to the fourth direction.

[0114] It should be noted that the embodiments of the present invention have better practicability and do not impose any form of limitation on the present invention. Any technician familiar with the field may use the technical content disclosed above to change or modify it into an equivalent effective embodiment. However, any modification or equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the content of the technical solution of the present invention are still within the scope of the technical solution of the present invention.

Claims

1. An automated control method for a coal mining process, characterized in that: include: During the manual operation of the coal mining process, the coal mining machine continuously collects geographical location information of the coal mining path at intervals of a first preset distance, stores externally input cutting parameters corresponding to each geographical location on the coal mining path, and obtains a first cutting parameter extraction table corresponding to the geographical location information and the cutting parameters; The method also continuously collects geological parameters of the coal body to be mined on the coal mining path at intervals of a second preset distance, and stores externally input cutting parameters corresponding to each position of the coal body to be mined on the coal mining path; determines in which range of several preset geological information ranges the geological parameters are located, and connects the stored cutting parameters with the preset geological information range to which the geological parameters of the corresponding position of the coal body to be mined belong, and obtains a second cutting parameter extraction table corresponding to the geological parameters and the cutting parameters; The coal mining machine, during the automatic coal mining process, selects to extract real-time cutting parameters according to the first cutting parameter extraction table and / or the second cutting parameter extraction table, and performs coal mining and cutting according to the real-time cutting parameters; The coal mining machine is arranged on a hydraulic support, and the hydraulic support includes a guide rail and a plurality of support frames arranged on the guide rail. The hydraulic support drives the coal mining machine to move on the guide rail and connect with the support frames of different groups through a frame moving action; the hydraulic support also reserves coal mining space for the coal mining machine through a frame retracting action; The hydraulic support is connected to a pump station, and the pump station includes a plurality of pump groups, and the number of the pump groups to be turned on is determined according to the pressure of the hydraulic support; The coal mining machine is provided with a position detection component, and each of the support frames is provided with a position receiving component that is in communication with the position detection component; each of the support frames is also provided with a controller, and the controller is connected to the position receiving component. When the position receiving component on the support frame receives the position signal of the position detection component, the controller controls the support frame to retract the frame; The three-dimensional position data of the coal mining machine during the coal mining process is obtained by an inertial navigation module provided on the coal mining machine, and the three-dimensional position data includes latitude and longitude information and altitude information; a coal mining work trajectory curve of the coal mining machine is drawn according to the three-dimensional position data; during the coal mining process of the coal mining machine, at intervals of a first preset time, it is continuously determined whether the straightness of the coal mining work trajectory curve is less than a preset straightness threshold value; if not, the coal mining face of the coal mining machine is controlled to move a preset distance in a first direction, a second direction, a third direction, or a fourth direction; the first direction, the second direction, the third direction, and the fourth direction are perpendicular to the forward direction of the coal mining machine, and the first direction is opposite to the second direction, and the third direction is opposite to the fourth direction; The coal mining machine continuously determines whether the straightness of the coal mining work trajectory curve is less than a preset straightness threshold at intervals of a first preset time during the coal mining process, and if not, controls the coal mining face of the coal mining machine to move a preset distance in the first direction, the second direction, the third direction, or the fourth direction, and further includes: While controlling the coal mining face of the coal mining machine to move toward the first direction, the second direction, the third direction, or the fourth direction, reducing the moving speed of the coal mining machine in the forward direction; Accumulate the number of times C that the coal mining face of the coal mining machine is controlled to move toward the first direction, the second direction, the third direction, or the fourth direction; When C is greater than the preset number, a coal mining machine failure prompt message is issued or a geological survey is requested; The coal mining machine, during the automatic coal mining process, selects to extract real-time cutting parameters according to the first cutting parameter extraction table and / or the second cutting parameter extraction table, and performs coal mining and cutting according to the real-time cutting parameters, and further includes: During the automatic coal mining process, the coal mining machine selects to extract real-time cutting parameters according to the first cutting parameter extraction table and / or the second cutting parameter extraction table again after a coal cutting cycle is completed, and performs coal mining and cutting according to the real-time cutting parameters; the coal cutting cycle is the coal cutting process in which the coal mining machine advances the first preset distance or the second preset distance; The determination of whether each item of actual cutting information is within the cutting parameter range includes: If the first cutting parameter extraction table is currently being extracted, it is determined whether each item of actual cutting information is respectively within the first cutting parameter range corresponding to the current geographical location information; the first cutting parameter range is the range of the error value of plus or minus 5% of the cutting parameter corresponding to the geographical location information in the first cutting parameter extraction table; If the second cutting parameter extraction table is currently being extracted, it is determined whether each item of actual cutting information is respectively within the second cutting parameter range corresponding to the current geological parameter; the second cutting parameter range is the range of error values ​​of plus or minus ten percent of the cutting parameter corresponding to the preset geological information range to which the geological parameter in the second cutting parameter extraction table belongs.

2. The automatic control method according to claim 1, characterized in that: It also includes a central control integrator, which is connected to the controller on each of the support frames and controls each of the controllers individually; The coal mining machine, each of the support frames, and the central control integrator are provided with communication modules, and the communication modules communicate with each other via a 5G network or wireless WIFI.

3. The automatic control method according to claim 2, characterized in that: The central control integrator comprises a first central control integrator arranged on the ground and a second central control integrator arranged in the coal mining well; When the controller receives the control signal of the first central control integrator, it stops receiving the control signal of the second central control integrator; when the controller receives the control signal of the second central control integrator, it stops receiving the control signal of the first central control integrator.

4. The automatic control method according to claim 1, characterized in that: The coal mining machine is provided with a position detection component, and each of the support frames is provided with a position receiving component that is in communication with the position detection component; each of the support frames is also provided with a controller, and the controller is connected to the position receiving component. When the position receiving component on the support frame receives the position signal of the position detection component, the controller controls the support frame to perform a frame retracting action, including: The position detection component is an infrared emission component, and the position receiving component is an infrared receiving component; the infrared signal emission range of the infrared emission component is S1, and the distance between two adjacent support frames is S2, where S2 < S1 < 2S2; the displacement speed V of the current shearer is obtained through the time difference of infrared signal reception between two adjacent support frames; when the displacement speed V is less than the first preset speed, the next set of support frames of the currently supported support frame performs the action of retracting the support frame; when the displacement speed V is greater than the first preset speed and less than the second preset speed, the next two sets of support frames of the currently supported support frame perform the action of retracting the support frame; when the displacement speed V is greater than the second preset speed, the next three sets of support frames of the currently supported support frame perform the action of retracting the support frame; the first preset speed is half of the speed required for the shearer to pass between two adjacent support frames in one minute, and the second preset speed is the speed required for the shearer to pass between two adjacent support frames in one minute. Or the position detection component is a shaft encoder for obtaining the displacement distance S3 of the current position of the shearer from the starting base point, and the position receiving component is a coded data receiver; the difference between the displacement distance S3 received by the coded data receiver and the distance of the support frame corresponding to this encoder from the starting base point is S4; the distance between two adjacent support frames is S2; when S2 < S4 < 2S2, the support frame corresponding to this encoder performs the action of retracting the support frame.

5. The automatic control method according to claim 1, characterized in that: The shearer is arranged on a hydraulic support, and the hydraulic support drives the shearer to move through the telescopic frame action. Controlling the shearer to move the coal mining face in the first direction or the second direction or the third direction or the fourth direction includes: Controlling the hydraulic support to perform the telescopic frame action so that the coal mining face of the shearer moves a preset distance in the first direction or the second direction or the third direction or the fourth direction.

6. The automatic control method according to claim 1, characterized in that: The position detection component is a shaft encoder, the position receiving component is a coded data receiver, and an infrared emission component is further provided on the shearer, and an infrared receiving component is further provided on each set of support frames. The displacement speed V of the current shearer is obtained through the time difference of infrared signal reception between two adjacent support frames. When the displacement speed V is less than the first preset speed, the next set of support frames of the currently supported support frame performs the action of retracting the support frame; when the displacement speed V is greater than the first preset speed and less than the second preset speed, the next two sets of support frames of the currently supported support frame perform the action of retracting the support frame; when the displacement speed V is greater than the second preset speed, the next three sets of support frames of the currently supported support frame perform the action of retracting the support frame. The first preset speed is half of the speed required for the shearer to pass between two adjacent support frames in one minute, and the second preset speed is the speed required for the shearer to pass between two adjacent support frames in one minute.

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