CN117145552A - Hydraulic control method for coal mine - Google Patents
Hydraulic control method for coal mine Download PDFInfo
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- CN117145552A CN117145552A CN202311201818.5A CN202311201818A CN117145552A CN 117145552 A CN117145552 A CN 117145552A CN 202311201818 A CN202311201818 A CN 202311201818A CN 117145552 A CN117145552 A CN 117145552A
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- hydraulic cylinder
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- 238000000034 method Methods 0.000 title claims abstract description 38
- 239000003245 coal Substances 0.000 title claims abstract description 31
- 238000005259 measurement Methods 0.000 claims abstract description 26
- 238000003745 diagnosis Methods 0.000 claims abstract description 21
- 230000002159 abnormal effect Effects 0.000 claims abstract description 11
- 239000010720 hydraulic oil Substances 0.000 claims description 13
- 238000005065 mining Methods 0.000 claims description 13
- 239000011159 matrix material Substances 0.000 claims description 6
- 239000003921 oil Substances 0.000 claims description 6
- 238000001514 detection method Methods 0.000 claims description 5
- 230000008602 contraction Effects 0.000 claims description 3
- 239000000284 extract Substances 0.000 claims description 3
- 230000005484 gravity Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000010586 diagram Methods 0.000 description 1
- 238000006073 displacement reaction Methods 0.000 description 1
Classifications
-
- E—FIXED CONSTRUCTIONS
- E21—EARTH OR ROCK DRILLING; MINING
- E21D—SHAFTS; TUNNELS; GALLERIES; LARGE UNDERGROUND CHAMBERS
- E21D23/00—Mine roof supports for step- by- step movement, e.g. in combination with provisions for shifting of conveyors, mining machines, or guides therefor
- E21D23/16—Hydraulic or pneumatic features, e.g. circuits, arrangement or adaptation of valves, setting or retracting devices
- E21D23/26—Hydraulic or pneumatic control
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- Engineering & Computer Science (AREA)
- Mining & Mineral Resources (AREA)
- Life Sciences & Earth Sciences (AREA)
- General Life Sciences & Earth Sciences (AREA)
- Geochemistry & Mineralogy (AREA)
- Geology (AREA)
- Fluid-Pressure Circuits (AREA)
Abstract
The application provides a hydraulic control method for a coal mine, which comprises the steps of firstly starting a hydraulic system and diagnosing faults of the hydraulic system; controlling the start/stop of the hydraulic system according to the fault diagnosis and the switching of the standby hydraulic cylinder; detecting the posture of the started hydraulic cylinder, judging whether the posture of the hydraulic cylinder meets the requirement, if so, continuing to operate the hydraulic cylinder, and if not, feeding back to fault diagnosis for secondary diagnosis; according to the application, the connecting rod, the shield beam and the top beam are supported by the hydraulic cylinder, the inclination angle sensor is arranged among the connecting rod, the shield beam and the top beam, and the supporting posture and the stretching/shrinking distance of the hydraulic cylinder are detected, so that the accurate measurement of the supporting posture of the hydraulic cylinder is realized, the abnormal states of the hydraulic cylinder and the supporting part of the hydraulic cylinder are accurately monitored in real time, and the supporting operation safety and stability of the hydraulic cylinder are improved.
Description
Technical Field
The application relates to a hydraulic control method for a coal mine, in particular to the technical field of hydraulic state detection.
Background
The hydraulic support is an important component of comprehensive coal mining equipment, and can reliably and effectively support and control the top plate of a working face, isolate a goaf and prevent gangue from entering the stope face and for equipment such as a conveyor to enter and exit a mine tunnel.
The coal mine hydraulic support in the prior art generally adopts a plurality of hydraulic supports to support the top of a mine hole, the hydraulic supports are positioned on two sides of the mine hole, the top of each hydraulic support is provided with a protection plate, the hydraulic supports are connected with the protection plates, so that the mine hole is supported, but the support structures all need to be stretched or contracted by means of stretching/shrinking of the hydraulic cylinders, when the middle section of the top of the mine hole is subjected to supporting acting force, the protection plates are always stressed to be fully applied to the hydraulic cylinders, and the hydraulic cylinders are continuously changed due to gravity in the use process of the coal mine, so that accurate early warning and protection cannot be made, and safety accidents are caused.
Disclosure of Invention
The application aims to: a hydraulic control method for coal mines is provided to solve the problems in the prior art.
The technical scheme is as follows: a hydraulic control method for a coal mine, comprising:
step 1, a hydraulic system is started,
step 2, performing fault diagnosis on the hydraulic system;
step 3, controlling the start/stop of the hydraulic system and the switching of the standby hydraulic cylinder according to the fault diagnosis;
step 4, detecting the gesture of the started hydraulic cylinder,
and 5, judging whether the posture of the hydraulic cylinder meets the requirement, if so, continuing to operate the hydraulic cylinder, and if not, feeding back to the step 3 to perform secondary fault diagnosis.
In a further embodiment, in step 1, the hydraulic system is started first, so that the hydraulic system is in a power-on delay triggering stage, and fault diagnosis is involved in the delay process.
In a further embodiment, step 2, after the fault diagnosis obtains the start command of the hydraulic system, the oil quantity and the pipeline in the hydraulic system in the non-running state and the to-be-running state of the hydraulic cylinder are detected, and when the fault of the hydraulic system in the non-running state is detected, the fault command is sent to the measurement and control unit, and the position of the fault point is prompted.
In a further embodiment, step 3, the measurement and control unit is used for judging the received fault instruction, judging whether the fault point is relieved, and operating the hydraulic system after the delay is completed when the fault point is relieved;
when the hydraulic system is not released, the hydraulic system in the time delay process is powered off, and when the hydraulic system fails in the running state, the measurement and control unit switches the standby hydraulic cylinder according to the set manual or automatic mode so that the hydraulic system can continue to run.
In a further embodiment, in the step 4, the posture of the hydraulic cylinder in the running state is detected, a hydraulic cylinder horizontal height calculation model is set, the height of the base of the hydraulic cylinder is set to be h1, and the lengths of the hydraulic rod driving connecting rod, the shield beam and the top beam are set to be h2, h3 and h4, and the specific expression is as follows:
H＝h1+h2×sinθ 1 +h3×sinθ 2 +h4×sinθ 3
wherein H represents the total height of H1, H2, H3 and H4 in the horizontal state of the hydraulic cylinder, and θ 1 Indicating the value of the included angle theta between the base and the connecting rod 2 Represents the value of the included angle theta between the shield beam and the base 3 And the numerical value of the included angle between the top beam and the base is shown.
In a further embodiment, the angle change of the base in the extending/contracting process of the hydraulic cylinder can lead the included angle between the shield beam and the top beam to be unchanged, the hydraulic cylinder is inclined, the original calculated height of the hydraulic cylinder can not obtain accurate data due to the inclination of the base, an inclination sensor is arranged at the matched included angle between the connecting rod, the shield beam and the top beam, the inclination generated by the base is calculated, the inclination angle beta is increased on the original included angle value, and the heights of the connecting rod, the shield beam and the top beam are obtained under the inclined state of the base by the hydraulic cylinder, wherein the specific expression is as follows:
H 1 ＝h1+h2×sin(θ 1 +β)+h3×sin(θ 2 +β)+h4×sin(θ 3 +β)
wherein H is 1 The height of the sum of h1, h2, h3 and h4 in the inclined state of the hydraulic cylinder is shown; beta represents the base inclination angle.
In a further embodiment, the transfer state of the hydraulic cylinder during extension/retraction is detected according to the state of the horizontal height or the inclined height of the hydraulic cylinder, and the specific expression is as follows:
y＝ay(k)+bd(k)
wherein y represents a transfer change value a representing a transfer matrix in a tilting state of the hydraulic cylinder; y (k) represents the coordinates of the pushing directions of the connecting rod, the shield beam and the top beam in the hydraulic cylinder after the kth coal mining of the coal mining machine, b represents the control matrix, and d (k) represents the stretching/shrinking distance of the hydraulic cylinder after the kth coal mining of the coal mining machine.
In a further embodiment, in the step 5, if an abnormal state occurs in the extending/contracting process or the extending/contracting stopping process of the hydraulic cylinder, the alarm module carries out alarm prompt on abnormal data, the measurement and control unit captures the abnormal data, controls and controls the start/stop of the hydraulic cylinder and the switching of the standby cylinder.
In a further embodiment, the hydraulic system comprises hydraulic oil, a hydraulic pump, an electromagnetic overflow valve, an electrohydraulic proportional valve and a hydraulic cylinder which are sequentially connected through pipelines; the hydraulic pump extracts hydraulic oil and transmits the hydraulic oil to the electromagnetic relief valve through a pipeline, the electromagnetic relief valve switches the path of the hydraulic oil, the flow regulation of the voltage proportional valve controls the extending/contracting moving speed of the hydraulic cylinder,
the fault diagnosis comprises a data acquisition module, wherein the data acquisition module comprises an inclination sensor, a pressure sensor and a measurement and control unit;
the inclination angle sensor collects the numerical value of the included angle of the connecting rod, the shield beam and the top beam under the extension/contraction of the hydraulic cylinder, and feeds back the collected data to the measurement and control unit;
the pressure sensor detects and compares the oil pressure in the pipeline and the pressure born by the hydraulic cylinder, if a gap exists in comparison values, the pipeline and the hydraulic cylinder are judged to have faults, and fault information is sent to the measurement and control unit;
the measurement and control unit receives detection signals of the inclination sensor and the pressure sensor, judges whether faults occur, detects faults in a starting delay state of the hydraulic system, detects operation faults and gives early warning prompts to the hydraulic cylinder in the operation process, and controls the starting/stopping of the hydraulic cylinder and the switching of the standby cylinder according to the setting range of fault points.
The beneficial effects are that: the application provides a hydraulic control method for a coal mine, which comprises the steps of supporting a connecting rod, a shield beam and a top beam through a hydraulic cylinder, arranging an inclination sensor among the connecting rod, the shield beam and the top beam, and detecting the supporting posture and the stretching/shrinking distance of the hydraulic cylinder, so that the accurate measurement of the supporting posture of the hydraulic cylinder is realized, the abnormal states of the hydraulic cylinder and the supporting part of the hydraulic cylinder are accurately monitored in real time, the supporting operation safety and stability of the hydraulic cylinder are improved, and the prediction track of the hydraulic cylinder and the supporting part after the displacement of the hydraulic cylinder is obtained by calculating the transferring state of the hydraulic cylinder; according to the predicted track change of the hydraulic cylinder, the pushing distance of the hydraulic cylinder supporting part is compensated, so that the hydraulic cylinder in an inclined state is straightened, then the expanding angles of the connecting rod, the shield beam and the top beam are calculated, the stretching/shrinking distance value of the hydraulic cylinder is obtained, the stretching/shrinking of the hydraulic cylinder is ensured to operate in a safe range, and in addition, the hydraulic cylinder which is not operated or is operated is controlled, so that the operation safety of the hydraulic cylinder is ensured.
Drawings
FIG. 1 is a schematic flow chart of the present application.
Fig. 2 is a schematic horizontal view of a hydraulic cylinder according to the present application.
Fig. 3 is a schematic view of the tilting of the hydraulic cylinder according to the present application.
Fig. 4 is a schematic diagram of a hydraulic cylinder system detection of the present application.
The reference numerals are: 1. hydraulic oil; 2. a hydraulic pump; 3. a pipe; 4. an electromagnetic spill valve; 5. an electrohydraulic proportional valve; 6. and a hydraulic cylinder.
Detailed Description
The applicant believes that the existing supporting structure is required to be expanded or contracted by means of extension/contraction of the hydraulic cylinder, when the middle section of the top of the mine cavity is subjected to supporting acting force, the force applied to the hydraulic cylinder is always applied to the protection plate, and the gravity applied to the hydraulic cylinder is continuously changed in the using process of the coal mine, so that accurate early warning and protection cannot be performed, and safety accidents are caused.
In order to solve the problems in the prior art, the application realizes accurate and controlled posture of the hydraulic cylinder support by using the hydraulic control method for the coal mine.
The present application will be described in more detail with reference to the following examples and the accompanying drawings.
The application provides a hydraulic control method for a coal mine, which comprises the following steps of:
step 1, starting a hydraulic system, namely starting the hydraulic system firstly, enabling the hydraulic system to be in a power-on delay triggering stage, and performing fault diagnosis intervention in a delay process.
Step 2, performing fault diagnosis on the hydraulic system; after the fault diagnosis obtains a starting instruction of the hydraulic system, detecting the oil quantity and a pipeline in the hydraulic system in a non-running state and the state to be operated of the hydraulic cylinder, and sending a fault instruction to the measurement and control unit and prompting the position of a fault point when the hydraulic system in the non-running state is detected.
Step 3, controlling the start/stop of the hydraulic system and the switching of the standby hydraulic cylinder according to the fault diagnosis; judging the received fault instruction by a measurement and control unit, judging whether the fault point is relieved, and enabling the hydraulic system to operate after the time delay is completed when the fault point is relieved;
when the hydraulic system is not released, the hydraulic system in the time delay process is powered off, and when the hydraulic system fails in the running state, the measurement and control unit switches the standby hydraulic cylinder according to the set manual or automatic mode so that the hydraulic system can continue to run.
Step 4, detecting the started hydraulic cylinder posture, detecting the hydraulic cylinder posture in an operating state, setting a hydraulic cylinder horizontal height calculation model, firstly setting the height of a base of the hydraulic cylinder as h1, and setting the lengths of a hydraulic rod driving connecting rod, a shield beam and a top beam as h2, h3 and h4, wherein the specific expression is as follows:
H＝h1+h2×sinθ 1 +h3×sinθ 2 +h4×sinθ 3
wherein H represents the total height of H1, H2, H3 and H4 in the horizontal state of the hydraulic cylinder, and θ 1 Indicating the value of the included angle theta between the base and the connecting rod 2 Represents the value of the included angle theta between the shield beam and the base 3 And the numerical value of the included angle between the top beam and the base is shown.
In a further embodiment, the angle change of the base in the extending/contracting process of the hydraulic cylinder can lead the included angle between the shield beam and the top beam to be unchanged, the hydraulic cylinder is inclined, the original calculated height of the hydraulic cylinder can not obtain accurate data due to the inclination of the base, an inclination sensor is arranged at the matched included angle between the connecting rod, the shield beam and the top beam, the inclination generated by the base is calculated, the inclination angle beta is increased on the original included angle value, and the heights of the connecting rod, the shield beam and the top beam are obtained under the inclined state of the base by the hydraulic cylinder, wherein the specific expression is as follows:
H 1 ＝h1+h2×sin(θ 1 +β)+h3×sin(θ 2 +β)+h4×sin(θ 3 +β)
wherein H is 1 The height of the sum of h1, h2, h3 and h4 in the inclined state of the hydraulic cylinder is shown; beta represents the base inclination angle.
In a further embodiment, the transfer state of the hydraulic cylinder during extension/retraction is detected according to the state of the horizontal height or the inclined height of the hydraulic cylinder, and the specific expression is as follows:
y＝ay(k)+bd(k)
wherein y represents a transfer change value a representing a transfer matrix in a tilting state of the hydraulic cylinder; y (k) represents the coordinates of the pushing directions of the connecting rod, the shield beam and the top beam in the hydraulic cylinder after the kth coal mining of the coal mining machine, b represents the control matrix, and d (k) represents the stretching/shrinking distance of the hydraulic cylinder after the kth coal mining of the coal mining machine.
And 5, judging whether the posture of the hydraulic cylinder meets the requirement, if so, continuing to operate the hydraulic cylinder, otherwise, feeding back to the step 3 for secondary fault diagnosis, and if an abnormal state occurs in the extending/contracting process or the extending/contracting stopping process of the hydraulic cylinder, carrying out alarm prompt on abnormal data by an alarm module, capturing the abnormal data by a measurement and control unit, controlling the starting/stopping of the hydraulic cylinder and the switching of the standby cylinder.
The hydraulic system comprises hydraulic oil 1, a hydraulic pump 2, an electromagnetic overflow valve 4, an electrohydraulic proportional valve 5 and a hydraulic cylinder 6 which are sequentially connected through pipelines; the hydraulic pump 2 extracts the hydraulic oil 1 and transmits the hydraulic oil to the electromagnetic relief valve 4 through a pipeline, the electromagnetic relief valve 4 switches the path of the hydraulic oil 1 and controls the extending/contracting moving speed of the hydraulic cylinder 6 through the flow adjustment of the voltage proportional valve,
the fault diagnosis comprises a data acquisition module, wherein the data acquisition module comprises an inclination sensor, a pressure sensor and a measurement and control unit;
the inclination angle sensor collects the values of the included angles of the connecting rod, the shield beam and the top beam under the extension/retraction of the hydraulic cylinder 6, and feeds back the collected data to the measurement and control unit;
the pressure sensor detects and compares the oil pressure in the pipeline 3 and the pressure born by the hydraulic cylinder 6, if a gap exists in comparison values, the pipeline 3 and the hydraulic cylinder 6 are judged to have faults, and fault information is sent to the measurement and control unit;
the measurement and control unit receives detection signals of the inclination sensor and the pressure sensor, judges whether faults occur, detects faults in a starting delay state of the hydraulic system, detects operation faults and gives early warning prompts to the hydraulic cylinder 6 in the operation process, and controls the starting/stopping of the hydraulic cylinder 6 and the switching of the standby cylinder according to the setting range of fault points.
As described above, although the present application has been shown and described with reference to certain preferred embodiments, it is not to be construed as limiting the application itself, since various changes in form and details may be made therein without departing from the spirit and scope of the application as defined by the appended claims.
Claims (9)
1. A hydraulic control method for a coal mine, comprising:
step 1, a hydraulic system is started,
step 2, performing fault diagnosis on the hydraulic system;
step 3, controlling the start/stop of the hydraulic system and the switching of the standby hydraulic cylinder according to the fault diagnosis;
step 4, detecting the gesture of the started hydraulic cylinder,
and 5, judging whether the posture of the hydraulic cylinder meets the requirement, if so, continuing to operate the hydraulic cylinder, and if not, feeding back to the step 3 to perform secondary fault diagnosis.
2. The method according to claim 1, wherein in step 1, the hydraulic system is started first, so that the hydraulic system is in a power-on delay triggering stage, and fault diagnosis is interposed in the delay process.
3. The method according to claim 1, wherein after the step 2 of fault diagnosis obtains a start command of the hydraulic system, oil quantity and pipeline in the hydraulic system in an unoperated state and a state to be operated of the hydraulic cylinder are detected, and when a fault occurs in the hydraulic system in the unoperated state, a fault command is sent to the measurement and control unit and the position of the fault point is prompted.
4. The method according to claim 1, wherein the step 3 is to judge whether the fault point is released or not by judging the received fault instruction by the measurement and control unit, and to operate the hydraulic system after the delay is completed when the fault point is released;
when the hydraulic system is not released, the hydraulic system in the time delay process is powered off, and when the hydraulic system fails in the running state, the measurement and control unit switches the standby hydraulic cylinder according to the set manual or automatic mode so that the hydraulic system can continue to run.
5. The hydraulic control method for coal mine as claimed in claim 1, wherein the step 4 is to detect the posture of the hydraulic cylinder in the running state and set a hydraulic cylinder horizontal height calculation model, firstly set the height of the base of the hydraulic cylinder to be h1, and set the lengths of the hydraulic rod driving connecting rod, the shield beam and the top beam to be h2, h3 and h4, and the specific expression is as follows:
H＝h1+h2×sinθ 1 +h3×sinθ 2 +h4×sinθ 3
wherein H represents the total height of H1, H2, H3 and H4 in the horizontal state of the hydraulic cylinder, and θ 1 Indicating the value of the included angle theta between the base and the connecting rod 2 Represents the value of the included angle theta between the shield beam and the base 3 And the numerical value of the included angle between the top beam and the base is shown.
6. The hydraulic control method for coal mines according to claim 1, wherein the angle change of the base in the extending/contracting process of the hydraulic cylinder can lead the included angle between the shield beam and the top beam to be unchanged, the inclination of the base can lead the original calculated height of the hydraulic cylinder to be incapable of obtaining accurate data, the inclination sensor is arranged at the matched included angle between the connecting rod, the shield beam and the top beam, the inclination generated by the base is calculated, the inclination angle beta is increased on the original included angle value, and the heights of the connecting rod, the shield beam and the top beam are obtained under the inclined state of the base by the hydraulic cylinder, wherein the specific expression is as follows:
H 1 ＝h1+h2×sin(θ 1 +β)+h3×sin(θ 2 +β)+h4×sin(θ 3 +β)
wherein H is 1 The height of the sum of h1, h2, h3 and h4 in the inclined state of the hydraulic cylinder is shown; beta represents the base inclination angle.
7. The hydraulic control method for coal mine as claimed in claim 1, wherein the transfer state of the hydraulic cylinder during the extension/retraction is detected according to the state of the horizontal height or the inclined height of the hydraulic cylinder, and the specific expression is as follows:
y＝ay(k)+bd(k)
wherein y represents a transfer change value a representing a transfer matrix in a tilting state of the hydraulic cylinder; y (k) represents the coordinates of the pushing directions of the connecting rod, the shield beam and the top beam in the hydraulic cylinder after the kth coal mining of the coal mining machine, b represents the control matrix, and d (k) represents the stretching/shrinking distance of the hydraulic cylinder after the kth coal mining of the coal mining machine.
8. The hydraulic control method for coal mines according to claim 1, wherein in the step 5, if an abnormal state occurs in the extending/contracting process or the extending/contracting stopping process of the hydraulic cylinder, the alarm module alarms and prompts abnormal data, the measurement and control unit captures the abnormal data, controls and controls the starting/stopping of the hydraulic cylinder and the switching of the spare cylinder.
9. The hydraulic control method for coal mines according to claim 1, wherein the hydraulic system comprises hydraulic oil, a hydraulic pump, an electromagnetic relief valve, an electrohydraulic proportional valve and a hydraulic cylinder which are sequentially connected through pipelines; the hydraulic pump extracts hydraulic oil and transmits the hydraulic oil to the electromagnetic relief valve through a pipeline, the electromagnetic relief valve switches the path of the hydraulic oil, the flow regulation of the voltage proportional valve controls the extending/contracting moving speed of the hydraulic cylinder,
the fault diagnosis comprises a data acquisition module, wherein the data acquisition module comprises an inclination sensor, a pressure sensor and a measurement and control unit;
the inclination angle sensor collects the numerical value of the included angle of the connecting rod, the shield beam and the top beam under the extension/contraction of the hydraulic cylinder, and feeds back the collected data to the measurement and control unit;
the pressure sensor detects and compares the oil pressure in the pipeline and the pressure born by the hydraulic cylinder, if a gap exists in comparison values, the pipeline and the hydraulic cylinder are judged to have faults, and fault information is sent to the measurement and control unit;
the measurement and control unit receives detection signals of the inclination sensor and the pressure sensor, judges whether faults occur, detects faults in a starting delay state of the hydraulic system, detects operation faults and gives early warning prompts to the hydraulic cylinder in the operation process, and controls the starting/stopping of the hydraulic cylinder and the switching of the standby cylinder according to the setting range of fault points.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311201818.5A CN117145552A (en) | 2023-09-18 | 2023-09-18 | Hydraulic control method for coal mine |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202311201818.5A CN117145552A (en) | 2023-09-18 | 2023-09-18 | Hydraulic control method for coal mine |
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| Publication Number | Publication Date |
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| CN117145552A true CN117145552A (en) | 2023-12-01 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202311201818.5A Pending CN117145552A (en) | 2023-09-18 | 2023-09-18 | Hydraulic control method for coal mine |
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| Country | Link |
|---|---|
| CN (1) | CN117145552A (en) |
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2023
- 2023-09-18 CN CN202311201818.5A patent/CN117145552A/en active Pending
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